Thermoluminescence of irradiated foodstuffs

NASA Astrophysics Data System (ADS)

Oduko, J. M.; Spyrou, N. M.

Measurements have been made of the thermoluminescent response of a number of foodstuffs, namely spices, chicken bone, eggshell and strawberries. From the results, irradiated samples can be clearly distinguished from unirradiated ones for several weeks after irradiation of 5-10 kGy, or in the case of some spices for up to 20 months. It is concluded that measurement of thermoluminescence is a promising technique for detecting the irradiation of foodstuffs.

A thermoluminescent method for aerosol characterization

NASA Technical Reports Server (NTRS)

Long, E. R., Jr.; Rogowski, R. S.

1976-01-01

A thermoluminescent method has been used to study the interactions of aerosols with ozone. The preliminary results show that ozone reacts with many compounds found in aerosols, and that the thermoluminescence curves obtained from ozonated aerosols are characteristic of the aerosol. The results suggest several important applications of the thermoluminescent method: development of a detector for identification of effluent sources; a sensitive experimental tool for study of heterogeneous chemistry; evaluation of importance of aerosols in atmospheric chemistry; and study of formation of toxic, electronically excited species in airborne particles.

Method of analysis of asbestiform minerals by thermoluminescence

DOEpatents

Fisher, Gerald L.; Bradley, Edward W.

1980-01-01

A method for the qualitative and quantitative analysis of asbestiform minerals, including the steps of subjecting a sample to be analyzed to the thermoluminescent analysis, annealing the sample, subjecting the sample to ionizing radiation, and subjecting the sample to a second thermoluminescent analysis. Glow curves are derived from the two thermoluminescent analyses and their shapes then compared to established glow curves of known asbestiform minerals to identify the type of asbestiform in the sample. Also, during at least one of the analyses, the thermoluminescent response for each sample is integrated during a linear heating period of the analysis in order to derive the total thermoluminescence per milligram of sample. This total is a measure of the quantity of asbestiform in the sample and may also be used to identify the source of the sample.

Preparation of Unconsolidated Sands for Microscopy Laboratory Exercises.

ERIC Educational Resources Information Center

Cameron, Barry; Jones, J. Richard

1988-01-01

Describes a technique of impregnating small amounts of sandy sediment in a quick curing resin for microscopic examination. Details the preparation of materials. Suggests laboratory exercises based on this preparation. (CW)

Los Alamos National Laboratory Prepares for Fire Season

ScienceCinema

L’Esperance, Manny

2018-01-16

Through the establishment of a Wildland Fire Program Office, and the Interagency Fire Base located on Laboratory property, Los Alamos National Laboratory is continuing and improving a program to prepare for wildland fire.

Los Alamos National Laboratory Prepares for Fire Season

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

L’Esperance, Manny

Through the establishment of a Wildland Fire Program Office, and the Interagency Fire Base located on Laboratory property, Los Alamos National Laboratory is continuing and improving a program to prepare for wildland fire.

Natural thermoluminescence of Antarctic meteorites and related studies

NASA Technical Reports Server (NTRS)

Benoit, Paul H.; Sears, Derek W. G.

1998-01-01

The natural thermoluminescence (TL) laboratory's primary purpose is to provide data on newly recovered Antarctic meteorites that can be included in discovery announcements and to investigate the scientific implications of the data. Natural TL levels of meteorites are indicators of recent thermal history and terrestrial history, and the data can be used to study the orbital/radiation history of groups of meteorites (e.g., H chondrites) or to study the processes leading to the concentration of meteorites at certain sites in Antarctica. An important application of these data is the identification of fragments, or "pairs" of meteorites produced during atmospheric passage or during terrestrial weathering. Thermoluminescence data are particularly useful for pairing within the most common meteorite classes, which typically exhibit very limited petrographic and chemical diversity. Although not originally part of the laboratory's objectives, TL data are also useful in the identification and classification of petrographically or mineralogically unusual meteorites, including unequilibrated ordinary chondrites and some basaltic achondrites. In support of its primary mission, the laboratory also engages in TL studies of modern falls, finds from hot deserts, and terrestrial analogs and conducts detailed studies of the TL properties of certain classes of meteorites. These studies include the measurement of TL profiles in meteorites, the determination of TL levels of finds from the Sahara and the Nullarbor region of Australia, and comparison of TL data to other indicators of irradiation or terrestrial history, such as cosmogenic noble gas and radionuclide abundances. Our current work can be divided into five subcategories, (a) TL survey of Antarctic meteorites, (b) pairing and field relations of Antarctic meteorites, (c) characterization of TL systematics of meteorites, (d) comparison of natural TL and other terrestrial age indicators for Antarctic meteorites, and for meteorites

Preparing Mars Science Laboratory Heat Shield

NASA Image and Video Library

2011-05-13

Technicians at Lockheed Martin Space Systems, Denver, prepare the heat shield for NASA Mars Science Laboratory. With a diameter of 4.5 meters nearly 15 feet, this heat shield is the largest ever built for a planetary mission.

Properties of Principal TL (Thermoluminescence) Dosimeters.

DTIC Science & Technology

1983-10-01

thermoluminescence dosimetry ( TLD ) emerged as the preferred means because of convenience of batch evaluation, reusability, large detection range, linearity and...personnel dosimetry , thermoluminescence dosimetry has emerged as a superior technique due to its manifold advantages over other methods of dose...their suitability for dosimetry . A brief description of important TL materials and their properties is documented in this report. DD ,JN 1473 EDITION 0

Laboratory Preparation in the Ocular Therapy Curriculum.

ERIC Educational Resources Information Center

Cummings, Roger W.

1986-01-01

Aspects of laboratory preparation necessary for undergraduate or graduate optometric training in the use of therapeutic drugs are discussed, including glaucoma therapy, anterior segment techniques, posterior segment, and systemic procedures. (MSE)

Thermoluminescence and photoluminescence of cerium doped CaSO 4 nanosheets

NASA Astrophysics Data System (ADS)

Zahedifar, M.; Mehrabi, M.

2010-12-01

Thermoluminescence (TL) and photoluminescence (PL) characteristics of CaSO 4:Ce nanocrystalline prepared by hydrothermal method has been studied. Its TL glow curve contains three overlapping glow peaks at around 490, 505 and 521 K. Emission spectra band at 303 and 324 nm were observed for the orthorhombic phase of nanosheets. TL response of the prepared nanocrystalline to β and γ radiation was studied and the sensitivity of the nanosheets was found much more than that of analogous microcrystalline and is around 10 times higher than the well known high sensitive TL dosimeter LiF:Mg, Cu, P (GR-200) hot-pressed chips. TL kinetic parameters of this nanocrystalline are also presented.

Thermoluminescent phosphor

DOEpatents

Lasky, Jerome B.; Moran, Paul R.

1978-01-01

A thermoluminescent phosphor comprising LiF doped with boron and magnesium is produced by diffusion of boron into a conventional LiF phosphor doped with magnesium. Where the boron dopant is made to penetrate only the outer layer of the phosphor, it can be used to detect shallowly penetrating radiation such as tritium beta rays in the presence of a background of more penetrating radiation.

Apparatuses and methods for laser reading of thermoluminescent phosphors

DOEpatents

Braunlich, Peter F.; Tetzlaff, Wolfgang

1989-01-01

Apparatuses and methods for rapidly reading thermoluminescent phosphors to determine the amount of luminescent energy stored therein. The stored luminescent energy is interpreted as a measure of the total exposure of the thermoluminescent phosphor to ionizing radiation. The thermoluminescent phosphor reading apparatus uses a laser to generate a laser beam. The laser beam power level is monitored by a laser power detector and controlled to maintain the power level at a desired value or values which can vary with time. A shutter or other laser beam interrupting means is used to control exposure of the thermoluminescent phosphor to the laser beam. The laser beam can be equalized using an opitcal equalizer so that the laser beam has an approximately uniform power density across the beam. The heated thermoluminescent phosphor emits a visible or otherwise detectable luminescent emission which is measured as an indication of the radiation exposure of the thermoluminscent phosphors. Also disclosed are preferred signal processing and control circuits including one system using a digital computer. Also disclosed are time-profiled laser power cycles for pre-anneal, read and post-anneal treatment of phosphors.

Thermoluminescent properties of rare earth doped lithium strontium borate phosphors

NASA Astrophysics Data System (ADS)

Jakathamani, S.; Annalakshmi, O.; Jose, M. T.

2018-04-01

Thermoluminescence (TL) of borates is remarkable in the field of radiation dosimetry because they can detect both neutron and gamma radiations. Usually, the TL efficiency of pure borates is low and hence dopants have to be added to increase their TL output. Their sensitivity and thermal stability vary widely and depend strongly on the preparation method. In this study polycrystalline powders of different rare earth doped thermoluminescent phosphors of Lithium Strontium borate (LSB) were synthesized by solid state sintering technique. Among the different rare earth dopants, the phosphor doped with cerium was found to have a simple glow curve structure with a dosimetric peak at around 265°C for a heating rate of 5°C/s. In order to study the effect of dopant on the TL characteristics, LSB phosphor with different concentrations of Ce dopant was synthesized and the TL intensity was found to be maximum for a dopant concentration of 0.7 mol%. All other important dosimetric characteristics like dose response and fading were carried out for the LSB:Ce (0.7 mol%) phosphor. Kinetic parameters like trap depth and frequency factor were determined using Peak shape method from Chen's equation.

Preliminary Studies of Thermoluminescence Dosimeter (TLD) CaSO4:Dy Synthesis

NASA Astrophysics Data System (ADS)

Nuraeni, N.; Iskandar, F.; Waris, A.; Haryanto, F.

2017-07-01

Thermoluminescence dosimeter (TLD) CaSO4:Dy was synthesised by coprecipitation. The TLD was observed after radiation exposure to Strontium-90. The thermoluminescence intensity was read using a TLD Reader Harshaw 3500. The thermoluminescent response obtained was 59.29 nC. Then re-annealing was conducted with the temperature varied at 700, 800 and 900 °C. The thermoluminescent intensity obtained at temperatures of 700 °C, 800 °C and 900 °C was 66.12 nC, 169.45 nC, and 552.37 nC respectively. The sensitivity of the TLD increased in response to the re-annealing temperature rise. In addition to observing the thermoluminescence properties, a comparison was made between the TLD obtained from this experiment with an existing TLD in the market. Finally, also the glow-curve characteristics of the TLD were observed.

Radiation and Health Technology Laboratory Capabilities

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

Bihl, Donald E.; Lynch, Timothy P.; Murphy, Mark K.

2005-07-09

The Radiological Standards and Calibrations Laboratory, a part of Pacific Northwest National Laboratory (PNNL)(a) performs calibrations and upholds reference standards necessary to maintain traceability to national standards. The facility supports U.S. Department of Energy (DOE) programs at the Hanford Site, programs sponsored by DOE Headquarters and other federal agencies, radiological protection programs at other DOE and commercial nuclear sites and research and characterization programs sponsored through the commercial sector. The laboratory is located in the 318 Building of the Hanford Site's 300 Area. The facility contains five major exposure rooms and several laboratories used for exposure work preparation, low-activity instrumentmore » calibrations, instrument performance evaluations, instrument maintenance, instrument design and fabrication work, thermoluminescent and radiochromic Dosimetry, and calibration of measurement and test equipment (M&TE). The major exposure facilities are a low-scatter room used for neutron and photon exposures, a source well room used for high-volume instrument calibration work, an x-ray facility used for energy response studies, a high-exposure facility used for high-rate photon calibration work, a beta standards laboratory used for beta energy response studies and beta reference calibrations and M&TE laboratories. Calibrations are routinely performed for personnel dosimeters, health physics instrumentation, photon and neutron transfer standards alpha, beta, and gamma field sources used throughout the Hanford Site, and a wide variety of M&TE. This report describes the standards and calibrations laboratory.« less

Thermoluminescence and lattice defects in LiF

NASA Technical Reports Server (NTRS)

Stoebe, T. G.; Watanabe, S.

1975-01-01

The principal effect of thermal and optical treatments in an ionic solid is to alter the lattice defect equilibrium, including the concentration and arrangement of ion vacancies, impurities, impurity-vacancy associates, and assorted electrons and holes which may be associated with such defects. This paper examines the relationship between these defects and thermoluminescence in the case of lithium fluoride at and above room temperature. The discussion focuses on lattice defect equilibrium, thermoluminescent trapping centers, the relationship between recombination and luminescence, the supralinearity and sensitization of the dosimetry grade of LiF and activation energy parameters.

Thermoluminescence properties of lithium magnesium borate glasses system doped with dysprosium oxide.

PubMed

Mhareb, M H A; Hashim, S; Ghoshal, S K; Alajerami, Y S M; Saleh, M A; Razak, N A B; Azizan, S A B

2015-12-01

We report the impact of dysprosium (Dy(3+)) dopant and magnesium oxide (MgO) modifier on the thermoluminescent properties of lithium borate (LB) glass via two procedures. The thermoluminescence (TL) glow curves reveal a single prominent peak at 190 °C for 0.5 mol% of Dy(3+). An increase in MgO contents by 10 mol% enhances the TL intensity by a factor of 1.5 times without causing any shift in the maximum temperature. This enhancement is attributed to the occurrence of extra electron traps created via magnesium and the energy transfer to trivalent Dy(3+) ions. Good linearity in the range of 0.01-4 Gy with a linear correlation coefficient of 0.998, fading as low as 21% over a period of 3 months, excellent reproducibility without oven annealing and tissue equivalent effective atomic numbers ~8.71 are achieved. The trap parameters, including geometric factor (μg), activation energy (E) and frequency factor (s) associated with LMB:Dy are also determined. These favorable TL characteristics of prepared glasses may contribute towards the development of Li2O-MgO-B2O3 radiation dosimeters. Copyright © 2015 John Wiley & Sons, Ltd.

Preparation and thermoluminescent dosimetry features of high sensitivity LiF:Mg,Ce phosphor

NASA Astrophysics Data System (ADS)

Shoushtari, M. K.; Zahedifar, M.; Sadeghi, E.

2018-04-01

Thermoluminescence (TL) kinetics and dosimetry features of newly produced LiF doped with Mg and Ce were investigated. Different contents of Mg (0-1 mol%) and Ce (0-2 mol%) were introduced in host material by melting method. The most TL sensitivity of the fabricated phosphor was obtained at 0.7 and 0.05 mol% concentrations of Mg and Ce impurities, respectively. The optimum pre-irradiation annealing regime of the synthesized LiF-based material was found at 350 °C for 10 min. Kinetic parameters of LiF:Mg,Ce dosimeter were obtained using different methods of computerized glow curve deconvolution (CGCD), initial rise (IR) and isothermal decay (ID). A good conformity are observed between the results obtained from different kinetic analysis methods. Other TL features such as fading, dose response and reusability were also examined.

Thin thermoluminescent dosimeter and method of making same

DOEpatents

Simons, Gale G.; DeBey, Timothy M.

1987-01-01

An improved thermoluminescent ionizing radiation dosimeter of solid, extremely thin construction for more accurate low energy beta dosimetry is provided, along with a method of fabricating the dosimeter. In preferred forms, the dosimeter is a composite including a backing support (which may be tissue equivalent) and a self-sustaining body of solid thermoluminescent material such as LiF having a thickness of less than about 0.25 millimeters and a volume of at least about 0.0125 mm.sup.3. In preferred fabrication procedures, an initially thick (e.g., 0.89 millimeters) TLD body is wet sanded using 600 grit or less sandpaper to a thickness of less than about 0.25 millimeters, followed by adhesively attaching the sanded body to an appropriate backing. The sanding procedure permits routine production of extremely thin (about 0.05 millimeters) TLD bodies, and moreover serves to significantly reduce non-radiation-induced thermoluminescence. The composite dosimeters are rugged in use and can be subjected to annealing temperatures for increased accuracy.

Thermoluminescence properties of Yb-Tb-doped SiO2 optical fiber subject to 6 and 10 MV photon irradiation

NASA Astrophysics Data System (ADS)

Sahini, M. H.; Wagiran, H.; Hossain, I.; Saeed, M. A.; Ali, H.

2014-08-01

This paper reports thermoluminescence characteristics of thermoluminescence dosimetry 100 chips and Yb-Tb-doped optical fibers irradiated with 6 and 10 MV photons. Thermoluminescence response of both dosimeters increases over a wide photon dose range from 0.5 to 4 Gy. Yb-Tb-doped optical fibers demonstrate useful thermoluminescence properties and represent a good candidate for thermoluminescence dosimetry application with ionizing radiation. The results of this fiber have been compared with those of commercially available standard thermoluminescence dosimetry-100 media. Commercially available Yb-Tb-doped optical fibers and said standard media are found to yield a linear relationship between dose- and thermoluminescence signal, although Yb-Tb-doped optical fibers provide only 10 % of the sensitivity of thermoluminescence dosimetry-100. With better thermoluminescence characteristics such as small size (125 μm diameter), high flexibility, easy of handling and low cost, as compared to other thermoluminescence materials, indicate that commercial Yb-Tb-doped optical fiber is a promising thermoluminescence material for variety of applications.

STRUCTURED LEARNING AND TRAINING ENVIRONMENTS--A PREPARATION LABORATORY FOR ADVANCED MAMMALIAN PHYSIOLOGY.

ERIC Educational Resources Information Center

FIEL, NICHOLAS J.; JOHNSTON, RAYMOND F.

A PREPARATION LABORATORY WAS DESIGNED TO FAMILIARIZE STUDENTS IN ADVANCED MAMMALIAN PHYSIOLOGY WITH LABORATORY SKILLS AND TECHNIQUES AND THUS SHORTEN THE TIME THEY SPEND IN SETTING UP ACTUAL EXPERIMENTS. THE LABORATORY LASTS 30 MINUTES, IS FLEXIBLE AND SIMPLE OF OPERATION, AND DOES NOT REQUIRE A PROFESSOR'S PRESENCE. THE BASIC TRAINING UNIT IS THE…

Thermoluminescence kinetics of pyrite (FeS2)

NASA Astrophysics Data System (ADS)

Silverman, A. N.; Levy, P. W.; Kierstead, J. A.

Thermoluminescence of pyrite (FeS2) was investigated to study the kinetics of single peak glow curves. The material used normally exhibits one large and four small peaks. However a glow curve can be obtained with only the large single peak that is suitable for testing thermoluminescence kinetics. Glow curves from aliquots of a single natural pyrite crystal studied in detail contain two low intensity thermoluminescence (TL) peaks at approximately 90 and 250 C, and two chemiluminescence (CL) peaks at approximately 350 and 430 C. The CL peaks are largely removable by initially heating the sample chamber under vacuum, pumping through liquid nitrogen traps, and recording glow curves immediately after helium is introduced, procedures which reduce system contaminants that react with pyrite. The shape, the variation of the temperature of the peak maximum (T(sub max)) with dose, and the retrapping to recombination cross section ratio (sigma) of the large 250 C peak are better described by the general one trap (GOT) kinetic equation, the basic equation from which the 1st and 2nd order kinetic equations are obtained as special cases, than by the 1st and 2nd order equations.

Thermoluminescence Dosimetry (TLD) and its Application in Medical Physics

NASA Astrophysics Data System (ADS)

Azorín Nieto, Juan

2004-09-01

Radiation dosimetry is fundamental in Medical Physics, involving patients and phantom dosimetry. In both cases thermoluminescence dosimetry (TLD) is the most appropriate technique for measuring the absorbed dose. In this paper thermoluminescence phenomenon as well as the use of TLD in radiodiagnosis and radiotherapy for in vivo or in phantom measurements is discussed. Some results of measurements made in radiotherapy and radiodiagnosis using home made LiF:Mg,Cu,P+PTFE TLD are presented.

Laboratory preparation questionnaires as a tool for the implementation of the Just in Time Teaching in the Physics I laboratories: Research training

NASA Astrophysics Data System (ADS)

Miranda, David A.; Sanchez, Melba J.; Forero, Oscar M.

2017-06-01

The implementation of the JiTT (Just in Time Teaching) strategy is presented to increase the previous preparation of students enrolled in the subject Physics Laboratory I offered at the Industrial University of Santander (UIS), Colombia. In this study, a laboratory preparation questionnaire (CPL) was applied as a tool for the implementation of JiTT combined with elements of mediated learning. It was found that the CPL allows to improve the students’ experience regarding the preparation of the laboratory and the development of the experimental session. These questionnaires were implemented in an academic manager (Moodle) and a web application (lab.ciencias.uis.edu.co) was used to publish the contents essential for the preparation of the student before each practical session. The most significant result was that the students performed the experimental session with the basic knowledge to improve their learning experience.

New thermoluminescence age estimates for the Nyos maar eruption (Cameroon Volcanic Line)

PubMed Central

Tchouankoue, Jean Pierre; Nkouamen Nemzoue, Peguy Noel; Ayaba, Félicité; Nformidah-Ndah, Siggy Signe; Nformi Chifu, Emmanuel

2017-01-01

Nyos maar is located in the Cameroon Volcanic Line and generates a multitude of primary and secondary hazards to the local population. For risk assessment and hazard mitigation, the age of the Nyos maar eruption provides some vital information. Since previous dating efforts using a range of techniques resulted in vastly varying eruption ages, we applied thermoluminescence (TL) methods to obtain independent and direct chronological constraints for the time of maar formation. Target minerals were granitic quartz clasts contained in pyroclastic surge deposits. Thermoluminescence plateau results prove that heat and/or pressure during the phreatomagmatic eruption was sufficient to reset the inherited luminescence signal of granitic bedrock quartz. Parallel application of three TL measurement protocols to one of the two samples gave consistent equivalent doses for the quartz ultra-violet emission. Despite the robustness of our dose estimates, the assessment of the dose rate was accompanied by methodological challenges, such as estimation of the original size distribution of quartz grains in the pyroclastic deposits. Considering results from additional laboratory analyses to constrain these uncertainties, we calculate an average maximum TL age of 12.3 ± 1.5 ka for the Nyos maar eruption. Based on these new data, a more solid risk assessment can be envisaged. PMID:28558057

New thermoluminescence age estimates for the Nyos maar eruption (Cameroon Volcanic Line).

PubMed

Schmidt, Christoph; Tchouankoue, Jean Pierre; Nkouamen Nemzoue, Peguy Noel; Ayaba, Félicité; Nformidah-Ndah, Siggy Signe; Nformi Chifu, Emmanuel

2017-01-01

Nyos maar is located in the Cameroon Volcanic Line and generates a multitude of primary and secondary hazards to the local population. For risk assessment and hazard mitigation, the age of the Nyos maar eruption provides some vital information. Since previous dating efforts using a range of techniques resulted in vastly varying eruption ages, we applied thermoluminescence (TL) methods to obtain independent and direct chronological constraints for the time of maar formation. Target minerals were granitic quartz clasts contained in pyroclastic surge deposits. Thermoluminescence plateau results prove that heat and/or pressure during the phreatomagmatic eruption was sufficient to reset the inherited luminescence signal of granitic bedrock quartz. Parallel application of three TL measurement protocols to one of the two samples gave consistent equivalent doses for the quartz ultra-violet emission. Despite the robustness of our dose estimates, the assessment of the dose rate was accompanied by methodological challenges, such as estimation of the original size distribution of quartz grains in the pyroclastic deposits. Considering results from additional laboratory analyses to constrain these uncertainties, we calculate an average maximum TL age of 12.3 ± 1.5 ka for the Nyos maar eruption. Based on these new data, a more solid risk assessment can be envisaged.

Laser readable thermoluminescent radiation dosimeters and methods for producing thereof

DOEpatents

Braunlich, Peter F.; Tetzlaff, Wolfgang

1989-01-01

Thin layer thermoluminescent radiation dosimeters for use in laser readable dosimetry systems, and methods of fabricating such thin layer dosimeters. The thin layer thermoluminescent radiation dosimeters include a thin substrate made from glass or other inorganic materials capable of withstanding high temperatures and high heating rates. A thin layer of a thermoluminescent phoshphor material is heat bonded to the substrate using an inorganic binder such as glass. The dosimeters can be mounted in frames and cases for ease in handling. Methods of the invention include mixing a suitable phosphor composition and binder, both being in particulate or granular form. The mixture is then deposited onto a substrate such as by using mask printing techniques. The dosimeters are thereafter heated to fuse and bond the binder and phosphor to the substrate.

Laser readable thermoluminescent radiation dosimeters and methods for producing thereof

DOEpatents

Braunlich, P.F.; Tetzlaff, W.

1989-04-25

Thin layer thermoluminescent radiation dosimeters for use in laser readable dosimetry systems, and methods of fabricating such thin layer dosimeters are disclosed. The thin layer thermoluminescent radiation dosimeters include a thin substrate made from glass or other inorganic materials capable of withstanding high temperatures and high heating rates. A thin layer of a thermoluminescent phosphor material is heat bonded to the substrate using an inorganic binder such as glass. The dosimeters can be mounted in frames and cases for ease in handling. Methods of the invention include mixing a suitable phosphor composition and binder, both being in particulate or granular form. The mixture is then deposited onto a substrate such as by using mask printing techniques. The dosimeters are thereafter heated to fuse and bond the binder and phosphor to the substrate. 34 figs.

The quality and scope of information provided by medical laboratories to patients before laboratory testing: Survey of the Working Group for Patient Preparation of the Croatian Society of Medical Biochemistry and Laboratory Medicine.

PubMed

Nikolac, Nora; Simundic, Ana-Maria; Kackov, Sanja; Serdar, Tihana; Dorotic, Adrijana; Fumic, Ksenija; Gudasic-Vrdoljak, Jelena; Klenkar, Kornelija; Sambunjak, Jadranka; Vidranski, Valentina

2015-10-23

The aim of this work was to evaluate to what extent the scope and content of information provided to patients is standardized across medical biochemistry laboratories in Croatia. Two on-line self-report surveys were sent out: Survey A regarding attitudes on importance of patient preparation and Survey B on the contents of patient preparation instructions. 13/118 laboratories (11%) do not provide written instructions to patients on how to prepare for laboratory testing, and 36 (40%) do not include information about water intake in their instructions. Only half of laboratories provide instructions for prostate-specific antigen (53.8%), female sex hormones (53.7%) and therapeutic drug monitoring (TDM) (52.5%). Inadequate information about fasting status (55.0%) and 24 hour urine collection (77.9%) were frequent errors with high severity and were associated with the greatest potential to cause patient harm. Laboratory professionals in Croatia have a positive attitude towards the importance of patient preparation for laboratory testing. However, the information for laboratory testing is not standardized and frequently lacks guidance for tests related to TDM, coagulation and endocrinology. This study highlights the need for standardized, updated and evidence-based recommendations for patient preparation in order to minimize the risk for patients. Copyright © 2015 Elsevier B.V. All rights reserved.

Beam profiles measured with thermoluminescent dosimeters

NASA Technical Reports Server (NTRS)

Lucks, H.; Marcowitz, S. M.; Wheeler, R. W.

1969-01-01

Beam profilometer, using thermoluminescent dosimeters, gives a quantitative and qualitative representation of the focus of an external protron beam of a synchrotron. The total number of particles in the beam, particle distribution, and the shape of the beam are determined.

Digital Mammography Breast Dosimetry Using Copper-Doped Lithium Fluoride (LiF:MCP) Thermoluminescent Dosimeters (TLDs)

DTIC Science & Technology

2003-06-18

Mammography Breast Dosimetry Using Copper-Doped Lithium Fluoride (LiF:MCP) Thermoluminescent Dosimeters ( TLDs ) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...34Digital Mammography Breast Dosimetry Using Copper- Doped Lithium Fluoride (LiF:MCP) Thermoluminescent Dosimeters ( TLDs )" Author: LT John J. Tomon...Title of Thesis: " Digital Mammography Breast Dosimetry Using Copper-Doped Lithium Fluoride (LiF:MCP) Thermoluminescent

Iodine Standard Materials: Preparation and Inter-Laboratory Comparisons

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

D D Jenson; M L Adamic; J E Olson

The Idaho National Laboratory is preparing to enter the community of AMS practioners who analyze for 129Iodine. We expect to take delivery of a 0.5 MV compact accelerator mass spectrometry system, built by NEC, in the early summer of 2014. The primary mission for this instrument is iodine; it is designed to analyze iodine in the +3 charge state. As part of the acceptance testing for this instrument, both at NEC and on-site in our laboratory, some sort of standard or reference material is needed to verify performance. Appropriate standard materials are not readily available in the commercial marketplace. Smallmore » quantities can sometimes be acquired from other laboratories already engaged in iodine analyses. In the longer-term, meaningful quantities of standard materials are needed for routine use in analyses, and for quality control functions1. We have prepared some standard materials, starting with elemental Woodward iodine and NIST SRM 3231 [Iodine-129 Isotopic Standard (high level)] 10-6 solution. The goal was to make mixtures at the 5x10-10, 5x10-11, 5x10-12 ratio levels, along with some unmodified Woodward, in the chemical form of silver iodide. Approximately twenty grams of each of these mixtures were prepared. The elemental Woodward iodine was dissolved in chloroform, then reduced to iodide using sodium bisulfite in water. At this point the NIST spike material was added, in the form of sodium iodide. The mixed iodides were oxidized back to iodine in chloroform using hydrogen peroxide. This oxidation step was essential for isotopic equilibration of the 127 and 129 atoms. The iodine was reduced to iodide using sodium bisulfite as before. Excess sulfites and sulfates were precipitated with barium nitrate. After decanting, silver nitrate was used to precipitate the desired silver iodide. Once the silver iodide was produced, the material was kept in darkness as much as possible to minimize photo-oxidation. The various mixtures were synthesized independently

An Alternative Approach for Preparing and Standardizing Some Common Aqueous Reagents Used in an Undergraduate Laboratory

ERIC Educational Resources Information Center

Melaku, Samuel; Dabke, Rajeev B.

2014-01-01

A guide for instructors and laboratory assistants to prepare some common aqueous reagents used in an undergraduate laboratory is presented. Dilute reagents consisting of H[superscript +](aq), I[subscript 3][superscript-](aq), Ce[superscript 4+](aq), and Ag[superscript+](aq) were prepared by electrolytic oxidation of respective precursors.…

Thermoluminescence, ESR and x-ray diffraction studies of CaSO4 : Dy phosphor subjected to post preparation high temperature thermal treatment

NASA Astrophysics Data System (ADS)

Bakshi, A. K.; Patwe, S. J.; Bhide, M. K.; Sanyal, B.; Natarajan, V.; Tyagi, A. K.; Kher, R. K.

2008-01-01

Thermoluminescence (TL), electron spin resonance (ESR) and x ray diffraction studies of CaSO4 : Dy phosphor subjected to post preparation high temperature treatment were carried out. Analysis of the TL glow curve indicated that the dosimetric glow peak at 240 °C reduces, whereas the low temperature satellite peak increases with the increase in the annealing temperature in the range 650-1000 °C. The influence of the annealing atmosphere on the TL glow curve structure was also observed. Reduction of the photoluminescence intensity of the annealed phosphor indicated that the environment of Dy3+ ions might have undergone some change due to high temperature treatment. Reduction in the ESR signal intensity corresponding to O_{3}^{-} and SO_{3}^{-} radicals was observed initially with the increase in the annealing temperaure; subsequently their intensity increased with temperature. Signals due to the SO_{4}^{-} radical vanished, when the phosphor was annealed beyond 800 °C. A signal corresponding to SH2- radicals was also observed in the ESR spectra for samples subjected to annealing in the temperature regime 800-1000 °C. XRD of the in situ annealed phosphor showed a change in the unit cell parameters. An endothermic peak at 860 °C in the DTA spectrum was observed.

Designing Online Resources in Preparation for Authentic Laboratory Experiences

PubMed Central

Boulay, Rachel; Parisky, Alex; Leong, Peter

2013-01-01

Professional development for science teachers can be benefited through active learning in science laboratories. However, how online training materials can be used to complement traditional laboratory training is less understood. This paper explores the design of online training modules to teach molecular biology and user perception of those modules that were part of an intensive molecular biology “boot camp” targeting high school biology teachers in the State of Hawaii. The John A. Burns School of Medicine at the University of Hawaii had an opportunity to design and develop professional development that prepares science teachers with an introduction of skills, techniques, and applications for their students to conduct medical research in a laboratory setting. A group of 29 experienced teachers shared their opinions of the online materials and reported on how they used the online materials in their learning process or teaching. PMID:24319698

Thermoluminescence dosimeters with narrow bandpass filters

DOEpatents

Walker, Scottie W.

2004-07-20

A dosimetry method exposes more than one thermoluminescence crystals to radiation without using conventional filters, and reads the energy stored in the crystals by converting the energy to light in a conventional manner, and then filters each crystal output in a different portion of the spectrum generated by the crystals.

Thermoluminescent response of LiF:Mg,Ti to 20 keV electrons.

PubMed

Mercado-Uribe, H; Brandan, M E

2002-01-01

The thermoluminescence response of LiF:Mg,Ti (TLD-100) to 20 keV electrons from a scanning electron microscope has been measured. Radiochromic dye films previously calibrated were used to determine the fluence incident on TLD-100 chips. The procedure for irradiation and glow curve deconvolution was adhered to the protocols previously determined in our laboratory for gamma rays and heavy charged particles. The response at electron fluences higher than 4 x 10(10) cm(-2) is supralinear, due to the increasingly relevant contribution of the high temperature peaks. The relative contribution of the high temperature peaks to the TL signal is abnormally small, about half that observed in gamma irradiation and four times smaller than what has been measured in low-energy X ray exposure.

An innovative blended learning approach using virtual patients as preparation for skills laboratory training: perceptions of students and tutors

PubMed Central

2013-01-01

Background Currently only a few reports exist on how to prepare medical students for skills laboratory training. We investigated how students and tutors perceive a blended learning approach using virtual patients (VPs) as preparation for skills training. Methods Fifth-year medical students (N=617) were invited to voluntarily participate in a paediatric skills laboratory with four specially designed VPs as preparation. The cases focused on procedures in the laboratory using interactive questions, static and interactive images, and video clips. All students were asked to assess the VP design. After participating in the skills laboratory 310 of the 617 students were additionally asked to assess the blended learning approach through established questionnaires. Tutors’ perceptions (N=9) were assessed by semi-structured interviews. Results From the 617 students 1,459 VP design questionnaires were returned (59.1%). Of the 310 students 213 chose to participate in the skills laboratory; 179 blended learning questionnaires were returned (84.0%). Students provided high overall acceptance ratings of the VP design and blended learning approach. By using VPs as preparation, skills laboratory time was felt to be used more effectively. Tutors perceived students as being well prepared for the skills laboratory with efficient uses of time. Conclusion The overall acceptance of the blended learning approach was high among students and tutors. VPs proved to be a convenient cognitive preparation tool for skills training. PMID:23402663

YAlO3:Ce3+ powders: Synthesis, characterization, thermoluminescence and optical studies

NASA Astrophysics Data System (ADS)

Parganiha, Yogita; Kaur, Jagjeet; Dubey, Vikas; Shrivastava, Ravi

2015-09-01

Yttrium aluminum perovskite (YAP) is a promising high temperature ceramic material, known for its mechanical, structural and optical properties. YAP's also known as an ideal host material for solid-state lasers and phosphors. In this work, Ce3+ doped YAlO3 phosphors were synthesized by solid state reaction method, which is very suitable technique for large scale production. A prepared phosphor was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Photoluminescence spectra and Thermoluminescence (TL) glow curve study. The starting reagents used for sample preparation are Y2O3, Al2O3 and CeO2, boric acid used as a flux. Ratio of Y:Al was 1:1 which shows perovskite structure confirmed by the X-ray diffraction (XRD) study. The entire prepared sample was studied by PL excitation and emission spectra. Prominent peak at 446 nm (blue emission) which shows broad emission spectra of photoluminescence. It proves that prepared phosphor can act as a single host for blue emission of light and can be used for display applications. Commission Internationale de I'Eclairage (CIE) techniques proves the blue emission of light (x = .148, y = .117). TL glow curve analysis of prepared phosphor shows the prominent peak at 189 °C for the variable UV exposure time and high temperature peak shows the more stability and less fading in the prepared phosphor. Kinetic data of prepared phosphor were evaluated by peak shape method for variable UV exposure time (5-25 min).

Preparing clinical laboratory science students with teaching skills.

PubMed

Isabel, Jeanne M

2010-01-01

Training clinical laboratory science (CLS) students in techniques of preparation and delivery of an instructional unit is an important component of all CLS education programs and required by the national accrediting agency. Participants of this study included students admitted to the CLS program at Northern Illinois University and enrolled in the teaching course offered once a year between the years of 1997 and 2009. Courses on the topic of "teaching" may be regarded by CLS students as unnecessary. However, entry level practitioners are being recruited to serve as clinical instructors soon after entering the workforce. Evaluation of the data collected indicates that students are better prepared to complete tasks related to instruction of a topic after having an opportunity to study and practice skills of teaching. Mentoring CLS students toward the career role of clinical instructor or professor is important to maintaining the workforce.

Thermoluminescent properties of ZnS:Mn nanocrystalline powders.

PubMed

Ortiz-Hernández, Arturo Agustín; Méndez García, Víctor Hugo; Pérez Arrieta, María Leticia; Ortega Sígala, José Juan; Araiza Ibarra, José de Jesús; Vega-Carrillo, Héctor Rene; Falcony Guajardo, Ciro

2015-05-01

Thermoluminescent ZnS nanocrystals doped with Mn(2+) ions were synthesized by chemical co-precipitation method. From X-ray diffraction studies it was observed that the synthesized nanoparticles have cubic zinc blende structure with average sizes of about 40-50nm. Morphology was analyzed by TEM. Photoluminescence studies showed two transitions, one of them close to 396nm and other close to 598nm, which is enhanced with increasing dopant concentration, this behavior was also observed in the cathodoluminescence spectrum. The thermoluminescence gamma dose-response has linear behavior over dose range 5-100mGy, the glow curve structure shows two glow peaks at 436K and at 518K that were taken into account to calculate the kinetic parameters using the Computerized Glow Curve Deconvolution procedure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preparation for microgravity: The role of the microgravity materials science laboratory

NASA Technical Reports Server (NTRS)

Johnston, J. Christopher; Rosenthal, Bruce N.; Meyer, Maryjo B.; Glasgow, Thomas K.

1988-01-01

A laboratory dedicated to ground based materials processing in preparation for space flight was established at the NASA Lewis Research Center. Experiments are performed to delineate the effects of gravity on processes of both scientific and commercial interest. Processes are modeled physically and mathematically. Transport model systems are used where possible to visually track convection, settling, crystal growth, phase separation, agglomeration, vapor transport, diffusive flow, and polymers reactions. The laboratory contains apparatus which functionally duplicates apparatus available for flight experiments and other pieces instrumented specifically to allow process characterization. Materials addressed include metals, alloys, salts, glasses, ceramics, and polymers. The Microgravity Materials Science Laboratory is staffed by engineers and technicians from a variety of disciplines and is open to users from industry and academia as well as the government. Examples will be given of the laboratory apparatus typical experiments and results.

Gamma radiation-induced thermoluminescence emission of minerals adhered to Mexican sesame seeds

NASA Astrophysics Data System (ADS)

Rodríguez-Lazcano, Y.; Correcher, V.; Garcia-Guinea, J.; Cruz-Zaragoza, E.

2013-02-01

The thermoluminescence (TL) emission of minerals isolated from Mexican sesame seeds appear as a good tool to discern between irradiated and non-irradiated samples. According to the X-ray diffraction (XRD) and environmental scanning electron microscope (ESEM) data, the adhered dust in both samples is mainly composed of different amounts of quartz and feldspars. These mineral phases exhibit (i) enough sensitivity to ionizing radiation inducing good TL intensity, (ii) high stability of the TL signal during the storage of the material, i.e. low fading, and (iii) are thermally and chemically stable. Blind tests were performed under laboratory conditions, but simulating industrial preservation processes, allow us to distinguish between 1 kGy gamma-irradiated and non-irradiated samples even 15 months after irradiation processing followed the EN 1788 European Standard protocol in sesame samples.

Thermoluminescence properties of gamma-irradiated nano-structure hydroxyapatite.

PubMed

Shafaei, M; Ziaie, F; Sardari, D; Larijani, M M

2016-02-01

The suitability of nano-structured hydroxyapatite (HAP) for use as a thermoluminescence dosimeter was investigated. HAP samples were synthesized using a hydrolysis method. The formation of nanoparticles was confirmed by X-ray diffraction and average particle size was estimated to be ~30 nm. The glow curve exhibited a peak centered at around 200 °C. The additive dose method was applied and this showed that the thermoluminescence (TL) glow curves follow first-order kinetics due to the non-shifting nature of Tm after different doses. The numbers of overlapping peaks and related kinetic parameters were identified from Tm -Tstop through computerized glow curve deconvolution methods. The dependence of the TL responses on radiation dose was studied and a linear dose response up to 1000 Gy was observed for the samples. Copyright © 2015 John Wiley & Sons, Ltd.

Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

NASA Astrophysics Data System (ADS)

Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

2015-08-01

Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the videos in five traditional laboratory experiments by integrating them with the standard pre-laboratory student preparation presentations and instructor demonstrations. We assessed the influence of the videos on student laboratory knowledge and performance, using sections of students who did not view the videos as the control. Our analysis of pre-quizzes revealed the control group had equivalent scores to the treatment group, while the post-quiz results show consistently greater learning gains for the treatment group. Additionally, the students who watched the videos as part of their pre-laboratory instruction completed their experiments in less time.

USAF Summer Research Program - 1993 High School Apprenticeship Program Final Reports, Volume 12, Armstrong Laboratory

DTIC Science & Technology

1993-12-01

on Panasonic TLD . Panasonic Industrial Company; Secaucus, New Jersey. 5. Thurlow, Ronald M. "Neutron Dosimetry Using a Panasonic Thermoluminescent...Radiation Dosimetry Branch Brooks Air Force Base San Antonio, Texas 78235 Final Report for: AFOSR Summer Research Program Armstrong Laboratory Sponsored...Associate Radiation Dosimetry Branch Armstrong Laboratory Abstract In an attempt to improve personnel monitoring for neutron emissions, Panasonic has

Can low-temperature thermoluminescence cast light on the nature of ultra-high dilutions?

PubMed

Rey, Louis

2007-07-01

Low-temperature thermoluminescence has been used in attempt to understand the particular structure of ultra high dilutions. Samples are activated by irradiation after freezing at the temperature of liquid nitrogen (77 degrees K). Experimental results show that, in the course of rewarming, the thermoluminescent glow is susbtantially different between dilutions of different substances. It is suggested that the dispersed gas phase might play a role in this process.

Asking the Next Generation: The Implementation of Pre-University Students' Ideas about Physics Laboratory Preparation Exercises

ERIC Educational Resources Information Center

Dunnett, K.; Bartlett, P. A.

2018-01-01

It was planned to introduce online pre-laboratory session activities to a first-year undergraduate physics laboratory course to encourage a minimum level of student preparation for experiments outside the laboratory environment. A group of 16 and 17 year old laboratory work-experience students were tasked to define and design a pre-laboratory…

Thermoluminescence dosimetry properties of new Cu doped CaF(2) nanoparticles.

PubMed

Zahedifar, M; Sadeghi, E

2013-12-01

Nanoparticles of Cu-doped calcium fluoride were synthesised by using the hydrothermal method. The structure of the prepared nanomaterial was characterised by the X-ray diffraction (XRD) pattern and energy dispersive spectrometer. The particle size of 36 nm was calculated from the XRD data. Its shape and size were also observed by scanning electron microscope. Thermoluminescence (TL) and photoluminescence of the produced phosphor were also considered. The computerised glow curve deconvolution procedure was used to identify the number of glow peaks included in the TL glow curve of the CaF2:Cu nanoparticles. The TL glow curve contains two overlapping glow peaks at ∼413 and 451 K. The TL response of this phosphor was studied for different Cu concentrations and the maximum sensitivity was found at 1 mol% of Cu impurity. Other dosimetric characteristics of the synthesised nanophosphor are also presented and discussed.

Thermoluminescence dating of archaeological artefacts from the Middle Neolithic, Bronze Age and the Roman Empire period.

PubMed

Berger, T; Hajek, M; Primerano, W; Vana, N

2002-01-01

Thermoluminescence (TL) dating was applied for artefacts found near the small village of Michelstetten, Lower Austria. Settlements in this region can be traced hack a long time and, according to archaeologists, the discovered artefacts may be as old as 6000 years. A modified sample preparation technique based on the fine-grain method was developed. This technique results in a higher reproducibility and reduces the overall preparation time. For some artefacts the new information of the TL dating leads to an unforeseen re-interpretation of the archaeological age. Furthermore, an iron furnace from the period of the Roman Empire could be dated. For the first time, it was possible to estimate correctly the point of time of the burn-down of an ancient wooden house via an analysis of the house's clay plaster. The fire took place in the sixth century; this was confirmed by dating ceramic artefacts.

TECHNIQUES OF TAPE PREPARATION AND DUPLICATION, WITH SUGGESTIONS FOR A LANGUAGE LABORATORY.

ERIC Educational Resources Information Center

Kansas State Dept. of Public Instruction, Topeka.

PART ONE OF THIS BULLETIN PROVIDES HELP IN THE TWO CRITICAL AREAS OF MASTER TAPE PREPARATION AND DUPLICATION. SUPPLEMENTED BY NUMEROUS PHOTOGRAPHS AND DIAGRAMS OF EQUIPMENT AND DUPLICATION TECHNIQUES, THE BULLETIN DESCRIBES MASTER PROGRAM DUPLICATION USING LANGUAGE LABORATORY EQUIPMENT, A PROFESSIONAL MASS DUPLICATOR, A TAPE RECORDER, A RECORD…

Implementation of a digital preparation validation tool in dental skills laboratory training.

PubMed

Kozarovska, A; Larsson, C

2018-05-01

To describe the implementation of a digital tool for preparation validation and evaluate it as an aid in students' self-assessment. Students at the final semester of skills laboratory training were asked to use a digital preparation validation tool (PVT) when performing two different tasks; preparation of crowns for teeth 11 and 21. The students were divided into two groups. Group A self-assessed and scanned all three attempts at 21 ("prep-and-scan"). Group B self-assessed all attempts chose the best one and scanned it ("best-of-three"). The situation was reversed for 11. The students assessed five parameters of the preparation and marked them as approved (A) or failed (F). These marks were compared with the information from the PVT. The students also completed a questionnaire. Each question was rated from 1 to 5. Teachers' opinions were collected at staff meetings throughout the project. Most students in the "prep-and-scan" groups showed an increase in agreement between their self-assessment and the information from the PVT, whereas students in the "best-of-three" groups showed lower levels of agreement. All students rated the PVT positively. Most strongly agreed that the tool was helpful in developing skills (mean 4.15), easy to use (mean 4.23) and that it added benefits in comparison to existing assessment tools (mean 4.05). They did not however, fully agree that the tool is time efficient (mean 2.55), and they did not consider it a substitute for verbal teacher feedback. Teachers' feedback suggested advantages of the tool in the form of ease of use, visual aid and increasing interest and motivation during skills laboratory training however, they did not notice a reduction in need of verbal feedback. Within the limitations of the study, our conclusion is that a digital PVT may be a valuable adjunct to other assessment tools in skills laboratory training. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Thermoluminescent dosimetry in electron beams: energy dependence.

PubMed

Robar, V; Zankowski, C; Olivares Pla, M; Podgorsak, E B

1996-05-01

The response of thermoluminescent dosimeters to electron irradiations depends on the radiation dose, mean electron energy at the position of the dosimeter in phantom, and the size of the dosimeter. In this paper the semi-empirical expression proposed by Holt et al. [Phys. Med. Biol. 20, 559-570 (1975)] is combined with the calculated electron dose fraction to determine the thermoluminescent dosimetry (TLD) response as a function of the mean electron energy and the dosimeter size. The electron and photon dose fractions, defined as the relative contributions of electrons and bremsstrahlung photons to the total dose for a clinical electron beam, are calculated with Monte Carlo techniques using EGS4. Agreement between the calculated and measured TLD response is very good. We show that the considerable reduction in TLD response per unit dose at low electron energies, i.e., at large depths in phantom, is offset by an ever-increasing relative contribution of bremsstrahlung photons to the total dose of clinical electron beams. This renders the TLD sufficiently reliable for dose measurements over the entire electron depth dose distribution despite the dependence of the TLD response on electron beam energy.

Online Graduates in Clinical Laboratory Sciences: Are They Prepared for the Workplace?

ERIC Educational Resources Information Center

Perry, Jennifer D.

2014-01-01

Online programs are increasing in the field of clinical laboratory sciences (CLS), however there is limited research regarding how well prepared online CLS program graduates are for the workplace, given that the field is highly hands-on skills based. Prior research suggests that online CLS graduates perform as well as their traditional graduate…

The analysis of thermoluminescent glow peaks of natural calcite after beta irradiation.

PubMed

Yildirim, R Güler; Kafadar, V Emir; Yazici, A Necmeddin; Gün, Esen

2012-09-01

In this study, the thermoluminescence properties of natural calcite samples were examined in detail. The glow curve of the sample irradiated with beta radiation shows two main peaks, P1 (at 115 °C) and P4 (at 254 °C). The additive dose, variable heating rate, computer glow curve deconvolution, peak shape and three point methods have been used to evaluate the trapping parameters, namely the order of kinetics (b), activation energy (E) and the frequency factor (s) associated with the dosimetric thermoluminescent glow peaks (P1 and P4) of natural calcite after different dose levels with beta irradiation.

Thermoluminescent properties of Dy doped calcium borate based glass for dose measurement subjected to photon irradiation

NASA Astrophysics Data System (ADS)

Tajuddin, H. A.; WanHassan, W. M. S.; Abdul Sani, S. F..; Shaharin, Nurul Syazlin

2017-10-01

This study presents the thermoluminescent (TL) dosimetric properties of calcium borate glass with various dopant concentration of dysprosium (Dy). Calcium borate glass is a new potential material to be used in radiation measurement with absorption coefficient that is close to human bone. A series of glasses based on chemical equation xCaO-(100-x) B2O3 system, x = 0.1, 0.2, 0.3, 0.4, 0.5 (0< x <100) % weight have been prepared by melt quenching method. The X-ray diffraction analysis of glass samples were carried out and the result showed a broad peak, which confirmed the amorphous nature of the glass. The 70B2O3-30CaO glass sample was found as the most stable among other glass samples studied. Present work focuses on 70B2O3-30CaO glass of (0.01-0.4) mol% Dy-doped in order to investigate the thermoluminescence (TL) properties, in particular, dose-response and fading. The glass samples were irradiated to dose range of 0.5-4.0 Gy subjected to 6MV photon irradiations of LINAC Primus MLC 3339. TL response of 0.3 mol% Dy-doped 70B2O3-30CaO glass was found to produce highest response, with good linear dose- response relationship.

Preparation and accreditation of anti-doping laboratories for the Olympic Games.

PubMed

Botrè, Francesco; Wu, Moutian; Boghosian, Thierry

2012-07-01

This article outlines the process of preparation of an anti-doping laboratory in view of the activities to be performed on the occasion of the Olympic Games, focusing in particular on the accreditation requirements of the World Anti-Doping Agency (WADA) and ISO/IEC 17025, as well as on the additional obligations required by the International Olympic Committee, which is the testing authority responsible for the anti-doping activities at the Olympics. Due to the elevated workload expected on the occasion of the Olympic Games, the designated anti-doping laboratory needs to increase its analytical capacity (samples processed/time) and capability by increasing the laboratory's resources in terms of space, instrumentation and personnel. Two representative cases, one related to the Winter Olympic Games (Torino 2006) and one related to the Summer Olympic Games (Beijing 2008), are presented in detail, in order to discuss the main aspects of compliance with both the WADA and ISO/IEC 17025 accreditation requirements.

Photoluminescence and thermoluminescence properties of BaGa2O4

NASA Astrophysics Data System (ADS)

Noto, L. L.; Poelman, D.; Orante-Barrón, V. R.; Swart, H. C.; Mathevula, L. E.; Nyenge, R.; Chithambo, M.; Mothudi, B. M.; Dhlamini, M. S.

2018-04-01

Rare-Earth free luminescent materials are fast becoming important as the cost of rare earth ions gradually increases. In this work, a Rare-Earth free BaGa2O4 luminescent compound was prepared by solid state chemical reaction, which was confirmed to have a single phase by X-ray Diffraction. The Backscattered Electron image and Energy Dispersive X-ray spectroscopy maps confirmed irregular particle and homogeneous compound formation, respectively. The Photoluminescence spectrum displayed broad emission between 350 to 650 nm, which was deconvoluted into two components. The photoluminescence excitation peak was positioned at 254 nm, which corresponds with the band-to-band position observed from the diffuse reflectance spectrum. The band gap was extrapolated to 4.65 ± 0.02 eV using the Kubelka-Munk model. The preliminary thermoluminescence results indicated that the kinetics involved were neither of first nor second order. Additionally, the activation energy of the electrons within the trap centres was approximated to 0.61 ± 0.01 eV using the Initial Rise model.

Thermoluminescence (TL) of europium-doped ZrO2 obtained by sol-gel method

NASA Astrophysics Data System (ADS)

Rivera, T.; Furetta, C.; Azorín, J.; Barrera, M.; Soto, A. M.

This article reports the preparation and characterization of europium-doped zirconium oxide (ZrO2:Eu3+) formed by homogeneous precipitation from propoxyde of zirconium [Zr(OC3H7)4]. The alkoxide sol gel process is an efficient method to prepare the zirconium oxide matrix by the hydrolysis of alkoxide precursors followed by condensation to yield a polymeric oxo-bridged ZrO2 network. All compounds were characterized by thermal analysis and the X-ray diffractometry method. The thermoluminescence (TL) emission properties of ZrO2:Eu3+ under beta radiation effects are studied. The europium-doped sintered zirconia powder presents a TL glow curve with two peaks (Tmax) centered at around 204 and around 292 °C, respectively. TL response of ZrO2:Eu3+ as a function of beta-absorbed dose was linear from 2 Gy up to 90 Gy. The europium ion (Eu3+)-doped ZrO2 was found to be more sensitive to beta radiation than undoped ZrO2 obtained by the same method and presented a little fading of the TL signal compared with undoped zirconium oxide.

Preparing chimpanzees for laboratory research.

PubMed

Bloomsmith, Mollie A; Schapiro, Steven J; Strobert, Elizabeth A

2006-01-01

The chimpanzee is the only representative of the Great Apes that is extensively involved in biomedical research in primate laboratories. These apes are used as animal models in a variety of studies, including research on infectious disease, parasitic disease, pharmacokinetic studies, neuroscience, cognition, and behavior. Chimpanzees used in biomedical research in the United States reside largely in six specialized research and holding facilities, and most of the research with them is conducted at these sites. Given the relatively small population of chimpanzees and its importance to biomedical research, it is imperative that we carefully manage the care, production, and use of these animals in biomedical research studies. Selection criteria and preparation techniques are reviewed in this article in an effort to begin a discussion on best practices for choosing and handling chimpanzees participating in biomedical research. The use of routine health assessment information is described for subject selection, as are behavioral issues to be considered. Due to the relatively small number of chimpanzees available, issues related to experimental design and multiple uses of chimpanzees are discussed. Practices related to the transportation and acclimation of chimpanzees are described. Finally, behavioral conditioning procedures are discussed, including habituation, desensitization, and positive reinforcement training that have been applied to reduce animal distress and improve the quality of the science being conducted with chimpanzee subjects.

Preparation of bone samples in the Gliwice Radiocarbon Laboratory for AMS radiocarbon dating.

PubMed

Piotrowska, N; Goslar, T

2002-12-01

In the Gliwice Radiocarbon Laboratory, a system for preparation of samples for AMS dating has been built. At first it was used to produce graphite targets from plant macrofossils and sediments. In this study we extended its capabilities with the preparation of bones. We dealt with 3 methods; the first was the classical Longin method of collagen extraction, the second one included additional treatment of powdered bone in alkali solution, while in the third one carboxyl carbon was separated from amino acids obtained after hydrolysis of protein. The suitability of the methods was tested on 2 bone samples. Most of our samples gave ages > 40 kyr BP, suggesting good performance of the adapted methods, except for one sample prepared with simple Longin method. For routine preparation of bones we chose the Longin method with additional alkali treatment.

Thermoluminescent dosimetry in veterinary diagnostic radiology.

PubMed

Hernández-Ruiz, L; Jimenez-Flores, Y; Rivera-Montalvo, T; Arias-Cisneros, L; Méndez-Aguilar, R E; Uribe-Izquierdo, P

2012-12-01

This paper presents the results of Environmental and Personnel Dosimetry made in a radiology area of a veterinary hospital. Dosimetry was realized using thermoluminescent (TL) materials. Environmental Dosimetry results show that areas closer to the X-ray equipment are safe. Personnel Dosimetry shows important measurements of daily workday in some persons near to the limit established by ICRP. TL results of radiation measurement suggest TLDs are good candidates as a dosimeter to radiation dosimetry in veterinary radiology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Thermoluminescent properties of some phosphor glasses based on aluminum oxide.

PubMed

El Mesady, I; Khaled, N; Hussein, A; El Samman, H; Alawsh, S

2016-12-01

The transparent thermoluminescent aluminum oxide-based glass of 15Al 2 O 3 -35P 2 O 5 -25CaO-25Na 2 CO 3 , abbreviated as APCN (all in mol%) doped with different concentrations of SiO 2 from 0.0-500 ppm was prepared using a conventional melt-quenching technique. The TL sensitivities of the prepared glasses were investigated at 3 Gy γ-dose using a 60 Co source and measured at a heating rate 10 C/sec. The highest TL intensity of the material doped with SiO 2 was found at a concentration of 500 ppm (APCNSi 5 ). Deconvolution of the glow curve from APCNSi 5 resulted in four peaks at about 161, 194, 237 and 293 C with a Figure Of Merit (FOM) of 1.28%. The APCNSi 5 specimen had the best dosimetric properties when compared with the other samples. Reproducibility, repeatability, dose-response curve and fading effect were checked for peak 3, which appeared at about 237 C. The results displayed that the APCNSi 5 glass system was a low-Z material (Z eff  ≈ 10), and had good reproducibility and good repeatability. Peak 3 showed good linearity over a dose range up to 20 Gy (R 2  = 0.999) and sublinearity behaviour was found. The signal from APCNSi 5 faded by about 11% after 2 days post irradiation, therefore it showed almost no significant loss. Such properties make the newly prepared glasses suitable for and highly recommended for use in γ-dosimeters. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Thermoluminescence characterization of the irradiated minerals extracted from nopal

NASA Astrophysics Data System (ADS)

Cruz-Zaragoza, E.; Furetta, C.; Kitis, G.; Gomez, B. T.; Polymeris, G. S.; Tsirliganis, N.; Loukou, Z.

2006-05-01

The mineral fraction from dehydrated nopal leaves (Opuntia ficus indica ) belonging to the Cactaceae family was extracted and selected by sizes of 10 and 74 mu m and exposed to 60 Co gamma radiation at different doses in the range 70 Gy-20 kGy. The glow-curves from these polyminerals show a thermoluminescence (TL) band with one very intense peak at a temperature around 150 degrees C and a second one emerging in the high temperature region, moving in a large zone of temperature values according to the preparation used and the level of irradiation. The XRD analysis shows a composition of both biominerals as whewellite and weddellite and a mineral fraction as anorthoclase and quartz. The main TL characteristics of the polymineral content of the nopal was analyzed, i.e . the TL response at different doses and fading during storage at room temperature. The activation energy of the traps responsible for the TL emission was also investigated and a possible continuous distribution of traps is discussed. A review of the scientific literature shows that this is the first time that a TL study on nopal ionized by irradiation has been carried out.

Photoluminescent and Thermoluminescent Studies of Dy3+ and Eu3+ Doped Y2O3 Phosphors.

PubMed

Verma, Tarkeshwari; Agrawal, Sadhana

2018-01-01

Eu 3+ doped and Dy 3+ codoped yttrium oxide (Y 2 O 3 ) phosphors have been prepared using solid-state reaction technique (SSR). The prepared phosphors were characterized by X-ray diffractometer (XRD), energy dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR) techniques. Photoluminescence (PL) and Thermoluminescence (TL) properties were studied in detail. PL emission spectra were recorded for prepared phosphors under excitation wavelength 254 nm, which show a high intense peak at 613 nm for Y 2 O 3 :Dy 3+ , Eu 3+ (1:1.5 mol %) phosphor. The correlated color temperature (CCT) and CIE analysis have been performed for the synthesized phosphors. TL glow curves were recorded for Eu 3+ doped and Dy 3+ codoped phosphors to study the heating rate effect and dose response. The kinetic parameters were calculated using peak shape method for UV and γ exposures through computerized glow curve deconvolution (CGCD) technique. The phosphors show second order kinetics and activation energies varying from 5.823 × 10 - 1 to 18.608 × 10 - 1  eV.

A new graphite preparation line for AMS 14C dating in the Zagreb Radiocarbon Laboratory

NASA Astrophysics Data System (ADS)

Krajcar Bronić, I.; Horvatinčić, N.; Sironić, A.; Obelić, B.; Barešić, J.; Felja, I.

2010-04-01

The new line for preparation of graphite samples for 14C dating by AMS has been constructed in the Zagreb Radiocarbon Laboratory. The performance of the rig and sample preparation procedure has been validated by preparing graphites from various reference materials of known 14C activity. The yield of the graphitization was good and the measured fraction of modern carbon ( Fm) values have not significantly deviated from the expected ones. Detailed analysis of measured Fm values indicates a slight bias to more positive values and should be carefully investigated.

Investigation of thermoluminescence properties of mobile phone screen displays as dosimeters for accidental dosimetry

NASA Astrophysics Data System (ADS)

Mrozik, Anna; Marczewska, B.; Bilski, P.; Kłosowski, M.

2014-11-01

The rapid assessment of the radiation dose after unexpected exposure is a task of accidental dosimetry. In case of a radiological accident glasses originating from mobile phone screens, placed usually near the human body, could be used as emergency thermoluminescent (TL) personal dosimeters. The time between irradiation and TL readout is crucial and therefore preparation of the mobile phone screens and their readout conditions should be optimized. The influence of the samples etching, bleaching and selection of the optical filters based on measurement of the emission spectrum of irradiated glass samples during heating for different types of mobile phones were the subjects of our investigation. Obtained results showed that glasses extracted from different brands of mobile phones have different dosimetric properties but all of them give a luminescent signal which can be used to calculate the dose.

Evaluation of discrepancies between thermoluminescent dosimeter and direct-reading dosimeter results

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

Shaw, K.R.

1993-07-01

Currently at Oak Ridge National Laboratory (ORNL), the responses of thermoluminescent dosimeters (TLDs) and direct-reading dosimeters (DRDs) are not officially compared or the discrepancies investigated. However, both may soon be required due to the new US Department of Energy (DOE) Radiological Control Manual. In the past, unofficial comparisons of the two dosimeters have led to discrepancies of up to 200%. This work was conducted to determine the reasons behind such discrepancies. For tests conducted with the TLDs, the reported dose was most often lower than the delivered dose, while DRDs most often responded higher than the delivered dose. Trends weremore » identified in personnel DRD readings, and ft was concluded that more training and more control of the DRDs could improve their response. TLD responses have already begun to be improved; a new background subtraction method was implemented in April 1993, and a new dose algorithm is being considered. It was concluded that the DOE Radiological Control Manual requirements are reasonable for identifying discrepancies between dosimeter types, and more stringent administrative limits might even be considered.« less

Thermoluminescence glow curve deconvolution and trapping parameters determination of dysprosium doped magnesium borate glass

NASA Astrophysics Data System (ADS)

Salama, E.; Soliman, H. A.

2018-07-01

In this paper, thermoluminescence glow curves of gamma irradiated magnesium borate glass doped with dysprosium were studied. The number of interfering peaks and in turn the number of electron trap levels are determined using the Repeated Initial Rise (RIR) method. At different heating rates (β), the glow curves were deconvoluted into two interfering peaks based on the results of RIR method. Kinetic parameters such as trap depth, kinetic order (b) and frequency factor (s) for each electron trap level is determined using the Peak Shape (PS) method. The obtained results indicated that, the magnesium borate glass doped with dysprosium has two electron trap levels with the average depth energies of 0.63 and 0.79 eV respectively. These two traps have second order kinetic and are formed at low temperature region. The obtained results due to the glow curve analysis could be used to explain some observed properties such as, high thermal fading and light sensitivity for such thermoluminescence material. In this work, systematic procedures to determine the kinetic parameters of any thermoluminescence material are successfully introduced.

Evaluation of a LiF:Mg,Ti thermoluminescent ring dosimeter according to the IEC 62387:2012 Standards

NASA Astrophysics Data System (ADS)

Oliveira, Edyelle L. B.; de Barros, Vinícius S. M.; Asfora, Viviane K.; Khoury, Helen J.

2018-03-01

This work shows results of type testing of a ring radiation dosimeter system under IEC 62387:2012. The personal dosimeter investigated in this work consists of a commercial one element plastic ring which contains an LiF:Mg,Ti thermoluminescent pellet. By applying requirements for statistical fluctuations and linearity, a minimum measurable dose in Hp(0.07) was established. Energy and angular dependence aided in determining energy correction factors and fading requirements were used to select the most appropriate preheat scheme. Type testing of passive radiation monitors was performed in the Radiation Metrology Laboratory (LMRI-DEN/UFPE) of the Federal University of Pernambuco and is a major step in Brazil for the independent evaluation of these dosimeters, currently not available in the country.

Validation of the Sysmex sp-1000i automated slide preparer-stainer in a clinical laboratory

PubMed Central

de Bitencourt, Eberson Damião dos Santos; Voegeli, Carlos Franco; Onzi, Gabriela dos Santos; Boscato, Sara Cardoso; Ghem, Carine; Munhoz, Terezinha

2013-01-01

Background The speed and quality of information have become essential items in the release of laboratory reports. The Sysmex®SP1000-I device has been developed to prepare and stain smear slides. However, for a device to be cleared for use in the laboratory routine it must pass through a validation process. Objective To evaluate the performance and reliability of the Sysmex® SP-1000i slide preparer-stainer incorporated into the routine of a hospital laboratory in Porto Alegre. Methods Peripheral blood samples of patients attending the laboratory for ambulatory exams with leukocyte counts between 7000/°L and 12,000/°L were evaluated, independent of gender and age. Two slides were prepared for each sample using the Sysmex® SP-1000i equipment; one of the slides was used to perform quality control tests using the CellaVision® DM96 device, and the other slide was used to compare pre-classification by the same device and the classification performed by a pharmacist-biochemist. Results The results of all the slides used as controls were acceptable according to the quality control test as established by the manufacturer of the device. In the comparison between the automated pre-classification and the classification made by the professional, there was an acceptable variation in the differential counts of leukocytes for 90% of the analyzed slides. Pearson correlation coefficient showed a strong correlation for band neutrophils (r = 0.802; p-value < 0.001), segmented neutrophils (r = 0.963; p-value < 0.001), eosinophils (r = 0.958; p-value < 0.001), lymphocytes (r = 0.985; p-value < 0.001) and atypical lymphocytes (r = 0.866; p-value < 0.001) using both methods. The red blood cell analysis was adequate for all slides analyzed by the equipment and by the professional. Conclusion The new Sysmex®SP1000-i methodology was found to be reliable, fast and safe for the routines of medium and large laboratories, improving the quality of microscopic analysis in complete blood

Thermoluminescence of pure and Eu-doped NaZnF3

NASA Astrophysics Data System (ADS)

Furetta, C.; Graziani, M.; Sanipoli, C.; Scacco, A.

Thermoluminescence of pure and Eu-doped NaZnF3 fluoroperovskite is studied in order to determine nature of emitting centres and possible dosimetric properties. Intrinsic and extrinsic defects, some of them due to surface oxidation processes, are related to peaks in the glow curves of the two systems.

Study of thermoluminescence response of purple to violet amethyst quartz from Balikesir, Turkey

NASA Astrophysics Data System (ADS)

Nur, N.; Yeğingil, Z.; Topaksu, M.; Kurt, K.; Doğan, T.; Sarıgül, N.; Yüksel, M.; Altunal, V.; Özdemir, A.; Güçkan, V.; Günay, I.

2015-09-01

In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appears to be one of the materials arousing the highest interest. In this study the dosimetric characteristics of natural amethyst quartz crystals collected from Balikesir-Dursunbey (Turkey) were investigated for the purpose of determination of the general properties that phosphors should have in order to be useful for thermoluminescence dosimetry. The natural thermoluminescence was drained by annealing the powder samples at 450 °C for 1.5 h. The effects of high temperature annealing, dose response curves, glow curves after a postirradiation annealing, reusability of the samples and storage of trapped electrons in dark at room temperature were clarified through irradiating the samples with the desired exposures by 90Sr/90Y beta particles. Isothermal annealing before and after irradiation was found to have a definite effect upon the TL glow curve of amethyst crystal powder. The same sample varied in sensitivity depending upon its previous thermal and radiation history. The peak heights of the glow peaks were examined with respect to dose response at dose levels between 1 Gy and 5 kGy. The intermediate temperature (IT) and high temperature (HT) peaks of 230 °C and 300 °C, respectively, exhibit dose-response curves as superlinear when dose is on the logarithmic scale except the dose response of 300 °C peak for the dose values of 1 < D < 20 Gy in which linear dose response was acquired. At the end of the storage time between exposure and readout which was about one month at room temperature, the emitted light reduction was 14% comparing to the initial state. Repeating the measurements of the same sample, exposed with 0.1, 0.5, 0.8 and 1 kGy beta exposures, resulted in between 4% and 11% increase in the TL sensitivity of the material.

Thermoluminescence response of rare earth activated zinc lithium borate glass

NASA Astrophysics Data System (ADS)

Saidu, A.; Wagiran, H.; Saeed, M. A.; Obayes, H. K.; Bala, A.; Usman, F.

2018-03-01

New glasses of zinc lithium borate doped with terbium oxide were synthesized by high temperature solid-state reaction. The amorphous nature of the glasses was confirmed using x-ray diffraction analysis (XRD). Thermoluminescence (TL) response of pure zinc lithium borate (ZLB) and zinc lithium borate doped with terbium (ZLB: Tb) exposed to gamma radiation was measured and compared. There is significant enhancement in the TL yields of ZLB: Tb compared to that of pure ZLB. Effect of varying concentration of dopant (Tb4O7) on the TL response of zinc lithium borate was investigated. 0.3 mol% concentration of Tb exhibited strongest TL intensity. Thermoluminescence curve of the phosphor consist of single isolated peak. The TL response of the new materials to the exposed radiation is linear within 0.5-100 Gy range of dose with sublinearity at the lower region of the curve. High sensitivity was exhibited by the new amorphous materials. Reproducibility, thermal fading and energy response of the proposed TLD were investigated and shows remarkable result that made the phosphor suitable for radiation dosimetry.

The response of a thermoluminescent dosimeter to low energy protons in the range 30-100 keV.

PubMed

Chu, T C; Lin, S Y; Hsu, C C; Li, J P

2001-11-01

This study demonstrates the thermoluminescence (TL) response of CaF2:Tm (commercial name TLD-300) to 30-100 keV protons which were generated by means of a Cockcroft-Walton accelerator. The phenomenon in which the total thermoluminescent output from CaF2:Tm (TLD-300) decreases with proton energy from 30 to 100 keV (with increase of LET) can be interpreted by the track structure theory (TST). The analysis of the glow peaks: P2 (131 degrees C), P3 (153.5 degrees C) and P6 (259 degrees C), of TLD-300 show the oscillatory decreasing phenomenon as a function of incident proton energy, which can be interpreted with the TST and the oscillatory emission of electrons in a thermoluminescent dosimeter (TLD) that is caused by resonant or quasi-resonant charge transfer in ion-atom interactions in this TLD-300.

Synthesis and thermoluminescence characterizations of Sr2B5O9Cl:Dy3+ phosphor for TL dosimetry.

PubMed

Oza, Abha H; Dhoble, N S; Park, K; Dhoble, S J

2015-09-01

The photoluminescence (PL) and thermoluminescence (TL) displayed by Dy-activated strontium haloborate (Sr2 B5 O9 Cl) were studied. A modified solid-state reaction was employed for the preparation of the phosphor. Photoluminescence spectra showed blue (484 nm) and yellow (575 nm) emissions due to incorporation of Dy(3+) into host matrix. The Dy-doped (0.5 mol%) Sr2 B5 O9 Cl was studied after exposure to γ-irradiation and revealed a prominent glow curve at 261°C with a small hump around 143°C indicating that two types of traps were generated. The glow peak at the higher temperature side (261°C) was more stable than the lower temperature glow peak. The TL intensity was 1.17 times less than that of the standard CaSO4 :Dy thermoluminescence dosimetry (TLD) phosphor, the phosphor showed a linear dose-response curve for different γ-ray irradiation doses (0.002-1.25 Gy) and fading of 5-7% was observed for higher temperature peaks upon storage. Trapping parameters and their estimated error values have been calculated by Chen's peak shape method and by the initial rise method. Values of activation energies estimated by both these techniques were comparable. The slight difference in activation energy values calculated by Chen's peak shape method indicated the formation of two kinds of traps Furthermore, slight differences in frequency values are due to various escaping and retrapping probabilities. Copyright © 2014 John Wiley & Sons, Ltd.

X-ray absorption spectroscopy and X-ray photoelectron spectroscopy studies of CaSO 4:Dy thermoluminescent phosphors

NASA Astrophysics Data System (ADS)

Bakshi, A. K.; Jha, S. N.; Olivi, L.; Phase, D. M.; Kher, R. K.; Bhattacharyya, D.

2007-11-01

Extended X-ray absorption fine structure (EXAFS) measurements have been carried out on CaSO4:Dy phosphor samples at the Dy L3 edge with synchrotron radiation. Measurements were carried out on a set of samples which were subjected to post-preparation annealing at different temperatures and for different cycles. The EXAFS data have been analysed to find the Dy-S and Dy-O bond lengths in the neighbourhood of the Dy atoms in a CaSO4 matrix. The observations from EXAFS measurements were verified with XANES and XPS techniques. On the basis of these measurements, efforts were made to explain the loss of thermoluminescence sensitivity of CaSO4:Dy phosphors after repeated cycles of annealing at 400 °C in air for 1 h.

Asking the next generation: the implementation of pre-university students’ ideas about physics laboratory preparation exercises

NASA Astrophysics Data System (ADS)

Dunnett, K.; Bartlett, P. A.

2018-01-01

It was planned to introduce online pre-laboratory session activities to a first-year undergraduate physics laboratory course to encourage a minimum level of student preparation for experiments outside the laboratory environment. A group of 16 and 17 year old laboratory work-experience students were tasked to define and design a pre-laboratory activity based on experiments that they had been undertaking. This informed the structure, content and aims of the activities introduced to a first year physics undergraduate laboratory course, with the particular focus on practising the data handling. An implementation study showed how students could try to optimise high grades, rather than gain efficiency-enhancing experience if careful controls were not put in place by assessors. However, the work demonstrated that pre-university and first-year physics students can take an active role in developing scaffolding activities that can help to improve the performance of those that follow their footsteps.

Entrance and exit dose measurements with semiconductors and thermoluminescent dosemeters: a comparison of methods and in vivo results.

PubMed

Loncol, T; Greffe, J L; Vynckier, S; Scalliet, P

1996-11-01

In order to compare diodes and TLD for in vivo dosimetry, systematic measurements of entrance and exit doses were performed with semiconductor detectors and thermoluminescent dosemeters for brain and head and neck patients treated isocentrically with external photon beam therapy. Scanditronix EDP-20 diodes and 7LiF thermoluminescent chips, irradiated in a 8 MV linac, were studied with similar build-up cap geometries and materials in order to assure an equivalent electronic equilibrium. Identical calibration methodology was applied to both detectors for the dose determination in clinical conditions. For the entrance dose evaluation over 249 field measurements, the ratio of the measured dose to the expected dose, calculated from tabulated tissue maximum ratios, was equal to 1.010 +/- 0.028 (1 s.d.) from diodes and 1.013 +/- 0.041 from thermoluminescent crystals. For the exit dose measurements, these ratios were equal to 0.998 +/- 0.049 and 1.016 +/- 0.070 for diodes and TLDs, respectively, after application of a simple inhomogeneity correction to the calculation of the expected exit dose. Thermoluminescence and semiconductors led to identical results for entrance and exit dose evaluation but TLDs were characterised by a lower reproducibility inherent to the TL process itself and to the acquisition and annihilation procedures.

Spectrophotometric determination of meclizine hydrochloride and pyridoxine hydrochloride in laboratory prepared mixtures and in their pharmaceutical preparation

NASA Astrophysics Data System (ADS)

Ibrahim, Maha M.; Elzanfaly, Eman S.; El-Zeiny, Mohamed B.; Ramadan, Nesreen K.; Kelani, Khadiga M.

2017-05-01

In this paper, three rapid, simple, accurate and precise spectrophotometric methods were developed for the determination of meclizine hydrochloride in the presence of pyridoxine hydrochloride without previous separation. The methods under study are dual wavelength (DWL), ratio difference (RD) and continuous wavelet transform (CWT). On the other hand, pyridoxine hydrochloride (PYH) was determined directly at 291 nm. The methods obey Beer's law in the range of (5-50 μg/mL) for both compounds. All the methods were validated according to the ICH guidelines where the accuracy was found to be 98.29, 99.59, 100.42 and 100.62% for DWL, RD, CWT and PYH; respectively. Moreover the precision of the methods were calculated in terms of %RSD and it was found to be 0.545, 0.372, 1.287 and 0.759 for DWL, RD,CWT and PYH; respectively. The selectivity of the proposed methods was tested using laboratory prepared mixtures and assessed by applying the standard addition technique. So, they can be used for the routine analysis of pyridoxine hydrochloride and meclizine hydrochloride in quality-control laboratories.

Effect of Pr 3+ concentration on thermoluminescence from K 2Y 1- xPr xF 5 crystals

NASA Astrophysics Data System (ADS)

Marcazzo, J.; Santiago, M.; Caselli, E.; Nariyama, N.; Khaidukov, N. M.

2004-06-01

Thermoluminescence dosimetric characteristics of K 2YF 5 crystals doped with Pr 3+ are reported for the first time. The efficiency of the 0.5 at.% Pr 3+ doped K 2YF 5 crystal has been found to be maximum for this concentration series and three times higher than that of the commercial dosimeter TLD-700. The thermoluminescence glow curve of this novel phosphor has no appreciable fading. Furthermore, it bears linear dose response and good stability after reutilization. According to these results, K 2YF 5:Pr 3+ appears to be a promising base for developing effective phosphors for TL solid state dosimetry. In this context, the spectral composition of the TL emission is also mentioned along with the values obtained by glow curve deconvolution for the trap parameters characterising electron trap centres involved in thermoluminescence.

Absorbed dose measurements on external surface of Kosmos-satellites with glass thermoluminescent detectors.

PubMed

Akatov YuA; Arkhangelsky, V V; Kovalev, E E; Spurny, F; Votochkova, I

1989-01-01

In this paper we present absorbed dose measurements with glass thermoluminescent detectors on external surface of satellites of Kosmos-serie flying in 1983-87. Experiments were performed with thermoluminescent aluminophosphate glasses of thicknesses 0.1, 0.3, 0.4, 0.5, and 1 mm. They were exposed in sets of total thickness between 5 and 20 mm, which were protected against sunlight with thin aluminized foils. In all missions, extremely high absorbed dose values were observed in the first layers of detectors, up to the thickness of 0.2 to 0.5 gcm-2. These experimental results confirm that, during flights at 250 to 400 km, doses on the surface of the satellites are very high, due to the low energy component of the proton and electron radiation.

Complexity of Reasoning about Children's Development: Links with Teacher-Preparation Content Courses and Supervised Laboratory Experience

ERIC Educational Resources Information Center

Guzell, Jacqueline R.; Stringer, Sharon A.

2004-01-01

In a sample of 74 university students studying early childhood and pre-kindergarten education, researchers assessed the relationships between child development knowledge, complexity of reasoning about development, prior work experience with children, and teacher-preparation content courses and laboratory courses. There was no statistically…

Co nanoparticle effects on the thermoluminescent signal induced by UV and gamma radiation in ZrO2 powders

NASA Astrophysics Data System (ADS)

Villa-Sánchez, G.; Mendoza-Anaya, D.; Eufemia Fernández-García, M.; Escobar-Alarcón, L.; Olea-Mejía, O.; González-Martínez, P. R.

2014-05-01

Zirconia powders, both pure and doped with Co nanoparticles were prepared by the sol-gel method followed by thermal treatment at 1000 °C. The morphological and crystallographic characteristics were studied by scanning and transmission electron microscopy, X-ray diffraction and the Rietveld refinements method. Analysis of the thermoluminescent (TL) signal induced by UV and gamma radiation was also conducted. According to the results, Co nanoparticles have a strong influence on the growth of ZrO2 particles and favor the formation of monoclinic zirconia. Moreover, an important influence of the added Co nanoparticles was observed on the position of the TL peaks of ZrO2, inducing a shift in the luminescence towards higher temperatures as well as the presence of more TL peaks at higher temperatures.

Issues in the reconstruction of environmental doses on the basis of thermoluminescence measurements in the Techa riverside

NASA Technical Reports Server (NTRS)

Bougrov, N. G.; Goksu, H. Y.; Haskell, E.; Degteva, M. O.; Meckbach, R.; Jacob, P.; Neta, P. I. (Principal Investigator)

1998-01-01

The potential of thermoluminescence measurements of bricks from the contaminated area of the Techa river valley, Southern Urals, Russia, for reconstructing external exposures of affected population groups has been studied. Thermoluminescence dating of background samples was used to evaluate the age of old buildings available on the river banks. The anthropogenic gamma dose accrued in exposed samples is determined by subtracting the natural radiation background dose for the corresponding age from the accumulated dose measured by thermoluminescence. For a site in the upper Techa river region, where the levels of external exposures were extremely high, the depth-dose distribution in bricks and the dependence of accidental dose on the height of the sampling position were determined. For the same site, Monte Carlo simulations of radiation transport were performed for different source configurations corresponding to the situation before and after the construction of a reservoir on the river and evacuation of the population in 1956. A comparison of the results provides an understanding of the features of the measured depth-dose distributions and height dependencies in terms of the source configurations and shows that bricks from the higher sampling positions are likely to have accrued a larger fraction of anthropogenic dose from the time before the construction of the reservoir. The applicability of the thermoluminescent dosimetry method to environmental dose reconstruction in the middle Techa region, where the external exposure was relatively low, was also investigated.

Neutron Activation and Thermoluminescent Detector Responses to a Bare Pulse of the CEA Valduc SILENE Critical Assembly

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

Miller, Thomas Martin; Celik, Cihangir; McMahan, Kimberly L.

This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 11, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). Themore » goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.« less

The Interpretation of Natural Thermoluminescence Data for Meteorites: Theoretical Basis and Practical Application

NASA Technical Reports Server (NTRS)

Benoit, P. H.; Sears, D. W. G.

2000-01-01

Natural thermoluminescence (TL) of ordinary chondrites reflects their irradiation and thermal history. We discuss the quantitative aspects of TL interpretation, with an emphasis on the terrestrial history of Antarctic meteorites and the orbital history of modern falls.

Food adulteration analysis without laboratory prepared or determined reference food adulterant values.

PubMed

Kalivas, John H; Georgiou, Constantinos A; Moira, Marianna; Tsafaras, Ilias; Petrakis, Eleftherios A; Mousdis, George A

2014-04-01

Quantitative analysis of food adulterants is an important health and economic issue that needs to be fast and simple. Spectroscopy has significantly reduced analysis time. However, still needed are preparations of analyte calibration samples matrix matched to prediction samples which can be laborious and costly. Reported in this paper is the application of a newly developed pure component Tikhonov regularization (PCTR) process that does not require laboratory prepared or reference analysis methods, and hence, is a greener calibration method. The PCTR method requires an analyte pure component spectrum and non-analyte spectra. As a food analysis example, synchronous fluorescence spectra of extra virgin olive oil samples adulterated with sunflower oil is used. Results are shown to be better than those obtained using ridge regression with reference calibration samples. The flexibility of PCTR allows including reference samples and is generic for use with other instrumental methods and food products. Copyright © 2013 Elsevier Ltd. All rights reserved.

The initial rise method extended to multiple trapping levels in thermoluminescent materials.

PubMed

Furetta, C; Guzmán, S; Ruiz, B; Cruz-Zaragoza, E

2011-02-01

The well known Initial Rise Method (IR) is commonly used to determine the activation energy when only one glow peak is presented and analysed in the phosphor materials. However, when the glow peak is more complex, a wide peak and some holders appear in the structure. The application of the Initial Rise Method is not valid because multiple trapping levels are considered and then the thermoluminescent analysis becomes difficult to perform. This paper shows the case of a complex glow curve structure as an example and shows that the calculation is also possible using the IR method. The aim of the paper is to extend the well known Initial Rise Method (IR) to the case of multiple trapping levels. The IR method is applied to minerals extracted from Nopal cactus and Oregano spices because the thermoluminescent glow curve's shape suggests a trap distribution instead of a single trapping level. Copyright © 2010 Elsevier Ltd. All rights reserved.

Environmental dosimeter of the thermoluminescent type

DOEpatents

Eichner, F.N.; Kocher, L.F.

1974-01-29

A dosimeter for accurately monitoring normally low-energy radiation including a thermoluminescent CaF phosphor enclosed within a tantalum capsule is described. The tantalum acts as a filter to weaken the measured dose due to photons having energies below about 0.2 MeV. Tantalum end caps are maintained on the capsule body by a polyolefin sheath formed from heat-contractable tubing. After exposing the dosimeter to environmental radiation, it is placed in a shielded chamber for about 24 h and subsequently annealed at about 80 deg C to release radiation energy accumulated in low-temperature traps. The dosimeter is then disassembled and the phosphors photometrically read at temperatures about 50 deg C to determine the absorbed radiation dose. (Official Gazette)

Thermoluminescence characteristics of Israeli household salts for retrospective dosimetry in radiological events

NASA Astrophysics Data System (ADS)

Druzhyna, S.; Datz, H.; Horowitz, Y. S.; Oster, L.; Orion, I.

2016-06-01

Following a nuclear accident or terror attack involving the dispersal of radioactive substances, radiation dose assessment to first responders and the members of the public is essential. The need for a retrospective assessment of the radiation dose to those possibly affected is, therefore, obligatory. The present study examines the potential use of Israeli household salt as a retrospective dosimeter (RD). The experiments were carried out on Israeli salt samples (NaCl) following a Nielsen market track survey based on scanning data representing the barcoded market, including organized and independent retail chains and a sample of private minimarkets and supermarkets. The technique used was thermoluminescence (TL) dosimetry. Salt samples were exposed to levels of dose from 0.5 mGy to 300 Gy at the Israeli Secondary Standard Dosimetry Laboratory of the Soreq Nuclear Research Center using a calibrated 137Cs source. Our emphasis has been on a detailed investigation of the basic dosimetric characteristics of the salts including: (i) glow curve analysis (ii) individual glow peak dose response (iii) reproducibility (iv) estimation of minimal measurable dose (v) effect of nitrogen readout, (vi) influence of humidity during pre-irradiation storage and (vii) light induced fading. The results are sufficiently favorable to lead to the conclusion that the Israeli household salts can serve as a pragmatic potential candidate for RD under certain restricted conditions. Occasional pre-calibration of the major salt brands in a dedicated laboratory may be essential depending on the required accuracy in the estimation of dose and consequent clinical evaluation.

Administration of Substances to Laboratory Animals: Equipment Considerations, Vehicle Selection, and Solute Preparation

PubMed Central

Turner, Patricia V; Pekow, Cynthia; Vasbinder, Mary Ann; Brabb, Thea

2011-01-01

Administration of substances to laboratory animals requires careful consideration and planning to optimize delivery of the agent to the animal while minimizing potential adverse experiences from the procedure. The equipment selected to deliver substances to animals depends on the length of the study and the nature of the material being administered. This selection provides a significant opportunity for refining animal treatment. Similarly, when substances are administered as solutions or suspensions, attention should be given to selection of vehicles and methods used for preparing the solutions and suspensions. The research team, veterinarian, technical personnel, and IACUC members should be aware of reasons underlying selection of equipment for substance delivery and should consider carefully how substances will be prepared and stored prior to administration to animals. Failure to consider these factors during experimental planning may result in unintentional adverse effects on experimental animals and confounded results. PMID:22330706

Sensitive Fibre-Based Thermoluminescence Detectors for High Resolution In-Vivo Dosimetry

NASA Astrophysics Data System (ADS)

Ghomeishi, Mostafa; Mahdiraji, G. Amouzad; Adikan, F. R. Mahamd; Ung, N. M.; Bradley, D. A.

2015-08-01

With interest in the potential of optical fibres as the basis of next-generation thermoluminescence dosimeters (TLDs), the development of suitable forms of material and their fabrication has become a fast-growing endeavour. Present study focuses on three types of Ge-doped optical fibres with different structural arrangements and/or shapes, namely conventional cylindrical fibre, capillary fibre, and flat fibre, all fabricated using the same optical fibre preform. For doses from 0.5 to 8 Gy, obtained at electron and photon energies, standard thermoluminescence (TL) characteristics of the optical fibres have been the subject of detailed investigation. The results show that in collapsing the capillary fibre into a flat shape, the TL yield is increased by a factor of 5.5, the yield being also some 3.2 times greater than that of the conventional cylindrical fibre fabricated from the same perform. This suggests a means of production of suitably sensitive TLD for in-vivo dosimeter applications. Addressing the associated defects generating luminescence from each of the optical fibres, the study encompasses analysis of the TL glow curves, with computerized glow curve deconvolution (CGCD) and 2nd order kinetics.

Sensitive Fibre-Based Thermoluminescence Detectors for High Resolution In-Vivo Dosimetry.

PubMed

Ghomeishi, Mostafa; Mahdiraji, G Amouzad; Adikan, F R Mahamd; Ung, N M; Bradley, D A

2015-08-28

With interest in the potential of optical fibres as the basis of next-generation thermoluminescence dosimeters (TLDs), the development of suitable forms of material and their fabrication has become a fast-growing endeavour. Present study focuses on three types of Ge-doped optical fibres with different structural arrangements and/or shapes, namely conventional cylindrical fibre, capillary fibre, and flat fibre, all fabricated using the same optical fibre preform. For doses from 0.5 to 8 Gy, obtained at electron and photon energies, standard thermoluminescence (TL) characteristics of the optical fibres have been the subject of detailed investigation. The results show that in collapsing the capillary fibre into a flat shape, the TL yield is increased by a factor of 5.5, the yield being also some 3.2 times greater than that of the conventional cylindrical fibre fabricated from the same perform. This suggests a means of production of suitably sensitive TLD for in-vivo dosimeter applications. Addressing the associated defects generating luminescence from each of the optical fibres, the study encompasses analysis of the TL glow curves, with computerized glow curve deconvolution (CGCD) and 2(nd) order kinetics.

Sensitive Fibre-Based Thermoluminescence Detectors for High Resolution In-Vivo Dosimetry

PubMed Central

Ghomeishi, Mostafa; Mahdiraji, G. Amouzad; Adikan, F. R. Mahamd; Ung, N. M.; Bradley, D. A.

2015-01-01

With interest in the potential of optical fibres as the basis of next-generation thermoluminescence dosimeters (TLDs), the development of suitable forms of material and their fabrication has become a fast-growing endeavour. Present study focuses on three types of Ge-doped optical fibres with different structural arrangements and/or shapes, namely conventional cylindrical fibre, capillary fibre, and flat fibre, all fabricated using the same optical fibre preform. For doses from 0.5 to 8 Gy, obtained at electron and photon energies, standard thermoluminescence (TL) characteristics of the optical fibres have been the subject of detailed investigation. The results show that in collapsing the capillary fibre into a flat shape, the TL yield is increased by a factor of 5.5, the yield being also some 3.2 times greater than that of the conventional cylindrical fibre fabricated from the same perform. This suggests a means of production of suitably sensitive TLD for in-vivo dosimeter applications. Addressing the associated defects generating luminescence from each of the optical fibres, the study encompasses analysis of the TL glow curves, with computerized glow curve deconvolution (CGCD) and 2nd order kinetics. PMID:26314683

Method of improving BeO as a thermoluminescent detector

DOEpatents

Gammage, Richard B.; Thorngate, John H.; Christian, Danny J.

1980-01-01

Measurements of radiation exposure below 1 mR are possible with a BeO ceramic thermoluminescent detector (TLD) by treating the TL signal in a manner that discriminates against an interferring pyroelectric incandescence (PI). This is accomplished by differentiating the signals electronically to cause the composite signal to cross the baseline. A zero-crossing detector then senses and clips the negative-going portion of the signal. The resultant signal is integrated, producing a result wherein the true TL signal is substantially greater than the PI signal.

Cathodoluminescence and Thermoluminescence of Undoped LTB and LTB:A (A = Cu, Ag, Mn)

DTIC Science & Technology

2013-03-01

operated, tabletop instrument for thermoluminescent dosimetry (TLD) measurements seen in Figure 3-8. It reads one dosimeter per loading and...the more sophisticated Riso TL/ OSL reader that Brant used at the University of Cincinnati [9]. Figure 4-12: TL data for LTB: Ag irradiated with 5

Thermoluminescent properties of nanocrystalline ZnTe thin films: Structural and morphological studies

NASA Astrophysics Data System (ADS)

Rajpal, Shashikant; Kumar, S. R.

2018-04-01

Zinc Telluride (ZnTe) is a binary II-VI direct band gap semiconducting material with cubic structure and having potential applications in different opto-electronic devices. Here we investigated the effects of annealing on the thermoluminescence (TL) of ZnTe thin films. A nanocrystalline ZnTe thin film was successfully electrodeposited on nickel substrate and the effect of annealing on structural, morphological, and optical properties were studied. The TL emission spectrum of as deposited sample is weakly emissive in UV region at ∼328 nm. The variation in the annealing temperature results into sharp increase in emission intensity at ∼328 nm along with appearance of a new peak at ∼437 nm in visible region. Thus, the deposited nanocrystalline ZnTe thin films exhibited excellent thermoluminescent properties upon annealing. Furthermore, the influence of annealing (annealed at 400 °C) on the solid state of ZnTe were also studied by XRD, SEM, EDS, AFM. It is observed that ZnTe thin film annealed at 400 °C after deposition provide a smooth and flat texture suited for optoelectronic applications.

Crystal scintillators for use in check-light source for thermoluminescent systems

NASA Astrophysics Data System (ADS)

Nagpal, J. S.; Sabharwal, S. C.; Chougaonkar, M. P.; Godbole, S. V.

1999-08-01

Beta ( 63Ni, Emax 0.063 MeV) excited radioluminescence of indigenously grown crystal scintillators CsI(Tl), Bi 4Ge 3O 12 and CdWO 4 has been studied for its use in check-light source needed for thermoluminescence systems. Temperature coefficient of the light output over 298-323 K and the beta-induced TL of the scintillators over 298-553 K are reported.

Thermoluminescence dating of Hawaiian basalt

USGS Publications Warehouse

May, Rodd James

1979-01-01

The thermoluminescence (TL) properties of plagioclase separates from 11 independently dated alkalic basalts 4,500 years to 3.3 million years old and 17 tholeiitic basalts 16 years to 450,000 years old from the Hawaiian Islands were investigated for the purpose of developing a TL dating method for young volcanic rocks. Ratios of natural to artificial TL intensity, when normalized for natural radiation dose rates, were used to quantify the thermoluminescence response of individual samples for age-determination purposes. The TL ratios for the alkalic basalt plagioclase were found to increase with age at a predictable exponential rate that permits the use of the equation for the best-fit line through a plot of the TL ratios relative to known age as a TL age equation. The equation is applicable to rocks ranging in composition from basaltic andesite to trachyte over the age range from about 2,000 to at least 250,000 years before present (B.P.). The TL ages for samples older than 50,000 years have a calculated precision of less than :t 10 percent and a potential estimated accuracy relative to potassium-argon ages of approximately :t 10 percent. An attempt to develop a similar dating curve for the tholeiitic basalts was not as successful, primarily because the dose rates are on the average lower than those for the alkalic basalts by a factor of 6, resulting in lower TL intensities in the tholeiitic basalts for samples of equivalent age, and also because the age distribution of dated material is inadequate. The basic TL properties of the plagioclase from the two rock types are similar, however, and TL dating of tholeiitic basalts should eventually be feasible over the age range 10,000 to at least 200,000 years B.P. The average composition of the plagioclase separates from the alkalic basalts ranges from oligoclase to andesine; compositional variations within this range have no apparent effect on the TL ratios. The average composition of the plagioclase from the tholeiitic

Thermoluminescence and Antarctic meteorites

NASA Technical Reports Server (NTRS)

Sears, D. W. G.; Hasan, F. A.

1986-01-01

The level of natural thermoluminescence (TL) in meteorites is the result of competition between build-up, due to exposure to cosmic radiation, and thermal decay. Antarctic meteorites tend to have lower natural TL than non-Antarctic meteorites because of their generally larger terrestrial ages. However, since a few observed falls have low TL due to a recent heating event, such as passage within approximately 0.7 astronomical units of the Sun, this could also be the case for some Antarctic meteorites. Dose rate variations due to shielding, heating during atmospheric passage, and anomalous fading also cause natural TL variations, but the effects are either relatively small, occur infrequently, or can be experimentally circumvented. The TL sensitivity of meteorites reflects the abundance and nature of the feldspar. Thus intense shock, which destroys feldspar, causes the TL sensitivity to decrease by 1 to 2 orders of magnitude, while metamorphism, which generates feldspar through the devitrification of glass, causes TL sensitivity to increase by a factor of approximately 10000. The TL-metamorphism relationship is particularly strong for the lowest levels of metamorphism. The order-disorder transformation in feldspar also affect the TL emission characteristics and thus TL provides a means of paleothermometry.

A Guide for Planning Facilities for Occupational Preparation Programs for Dental Laboratory Technicians. Research Series No. 34.

ERIC Educational Resources Information Center

Macconnell, James D., And Others

The twelfth in a series also including guides for facilities for medical x-ray technologist, medical assistant, and medical secretary programs, the document is intended for use in the preparation of educational specifications for facilities for dental laboratory technician programs. Designed for use by those responsible for planning facilities,…

Synthesis, characteristics and thermoluminescent dosimetry features of γ-irradiated Ce doped CaF2 nanophosphor.

PubMed

Zahedifar, M; Sadeghi, E; Mozdianfard, M R; Habibi, E

2013-08-01

Nanoparticles of cerium doped calcium fluoride (CaF2:Ce) were synthesized for the first time using the hydrothermal method. The formation of nanostructures was confirmed by X-ray diffraction (XRD) patterns, indicating cubic lattice structure for the particles produced. Their shape and size were observed by scanning electron microscopy (SEM). Thermoluminescence characteristics were studied by having the samples irradiated by gamma rays of (60)Co source. The optimum thermal treatment of 400 °C for 30 min was found for the produced nanoparticles. The Tm-Tstop and computerized glow curve deconvolution (CGCD) methods, used to determine the number of component glow peaks and kinetic parameters, indicated seven overlapping glow peaks on the TL glow curve at approximately 394, 411, 425, 445, 556, 594 and 632 K. A linear dose response of up to 2000 Gy, was observed for the prepared nanoparticles. Maximum TL sensitivity was found at 0.4 mol% of Ce impurity. Other TL dosimetry features, including reusability and fading, were also presented and discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

In vivo thermoluminescence dosimetry for total body irradiation.

PubMed

Palkosková, P; Hlavata, H; Dvorák, P; Novotný, J; Novotný, J

2002-01-01

An improvement in the clinical results obtained using total body irradiation (TBI) with photon beams requires precise TBI treatment planning, reproducible irradiation, precise in vivo dosimetry, accurate documentation and careful evaluation. In vivo dosimetry using LiF Harshaw TLD-100 chips was used during the TBI treatments performed in our department. The results of in vivo thermoluminescence dosimetry (TLD) show that using TLD measurements and interactive adjustment of some treatment parameters based on these measurements, like monitor unit calculations, lung shielding thickness and patient positioning, it is possible to achieve high precision in absorbed dose delivery (less than 0.5%) as well as in homogeneity of irradiation (less than 6%).

Effect of thermal annealing on the thermoluminescent properties of nano-calcium fluoride and its dose-response characteristics.

PubMed

Mundupuzhakal, J K; Biswas, R H; Chauhan, S; Varma, V; Acharya, Y B; Chakrabarty, B S

2015-12-01

Nano-CaF2, prepared by the co-precipitation method, was annealed under different annealing conditions to improve its thermoluminescence (TL) characteristics. Different annealing parameters, such as temperature (400-700°C), duration (1-4 h) and environment (vacuum and air), were explored. The effect on TL sensitivity, peak position (Tm) and full-width at half-maximum (FWHM) with respect to the different annealing conditions are discussed as they are the measure of crystallinity of the material. Annealing temperature of 500°C with annealing duration of two and a half hours in vacuum provided the highest luminescence response (i.e. maximum sensitivity, minimum peak temperature and FWHM). Wide detectable dose range (5 mGy to 2 kGy), absence of thermal quenching and sufficient activation energy (1.04 eV) of this phosphor make it suitable for dosimetric applications. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Air Force Research Laboratory Preparation for Year 2000.

DTIC Science & Technology

1998-10-05

Air Force Research Laboratory , Phillips Research Site , Kirkland Air Force Base, New...Pentagon, Washington, D.C. 20301-1900. The identity of each writer and caller is fully protected. Acronym AFRL Air Force Research Laboratory INSPECTOR...completion of the implementation phase was May 31, 1999. Air Force Research Laboratory . The Air Force Research

The NOSAMS sample preparation laboratory in the next millenium: Progress after the WOCE program

NASA Astrophysics Data System (ADS)

Gagnon, Alan R.; McNichol, Ann P.; Donoghue, Joanne C.; Stuart, Dana R.; von Reden, Karl; Nosams

2000-10-01

Since 1991, the primary charge of the National Ocean Sciences AMS (NOSAMS) facility at the Woods Hole Oceanographic Institution has been to supply high throughput, high precision AMS 14C analyses for seawater samples collected as part of the World Ocean Circulation Experiment (WOCE). Approximately 13,000 samples taken as part of WOCE should be fully analyzed by the end of Y2K. Additional sample sources and techniques must be identified and incorporated if NOSAMS is to continue in its present operation mode. A trend in AMS today is the ability to routinely process and analyze radiocarbon samples that contain tiny amounts (<100 μg) of carbon. The capability to mass-produce small samples for 14C analysis has been recognized as a major facility goal. The installation of a new 134-position MC-SNICS ion source, which utilizes a smaller graphite target cartridge than presently used, is one step towards realizing this goal. New preparation systems constructed in the sample preparation laboratory (SPL) include an automated bank of 10 small-volume graphite reactors, an automated system to process organic carbon samples, and a multi-dimensional preparative capillary gas chromatograph (PCGC).

ASSESSMENT OF EYE LENS DOSES IN INTERVENTIONAL RADIOLOGY: A SIMULATION IN LABORATORY CONDITIONS.

PubMed

Čemusová, Z; Ekendahl, D; Judas, L

2016-09-01

As workers in interventional radiology belong to one of the most occupationally exposed groups, methods for sufficiently accurate quantification of their external exposure are sought. The objective of the authors' experiment was to investigate the relations between eye lens dose and Hp(10), Hp(3) or Hp(0.07) values measured with a conventional whole-body personal thermoluminescence dosemeter (TLD). Conditions of occupational exposure during common interventional procedures were simulated in laboratory. An anthropomorphic phantom represented a physician. The TLDs were fixed to the phantom in different locations that are common for purposes of personal dosimetry. In order to monitor the dose at the eye lens level during the exposures, a special thermoluminescence eye dosemeter was fixed to the phantom's temple. Correlations between doses measured with the whole-body and the eye dosemeters were found. There are indications that personnel in interventional radiology do not need to be unconditionally equipped with additional eye dosemeters, especially if an appropriate whole-body dosimetry system has been already put into practice. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The calculation of mass attenuation coefficients of well-known thermoluminescent dosimetric compounds at wide energy range

NASA Astrophysics Data System (ADS)

Ermis, Elif Ebru

2017-02-01

The photon mass attenuation coefficients of LiF, BaSO4, CaCO3 and CaSO4 thermoluminescent dosimetric compounds at 100; 300; 500; 600; 800; 1,000; 1,500; 2,000; 3,000 and 5,000 keV gamma-ray energies were calculated. For this purpose, FLUKA Monte Carlo (MC) program which is one of the well-known MC codes was used in this study. Furthermore, obtained results were analyzed by means of ROOT program. National Institute of Standards and Technology (NIST) values were also used to compare the obtained theoretical values because the mass attenuation values of the used compounds could not found in the literature. Calculated mass attenuation coefficients were highly in accordance with the NIST values. As a consequence, FLUKA was successful in calculating the mass attenuation coefficients of the most used thermoluminescent compound.

Feasibility study of CaSO4:Tb,Yb as a thermoluminescent dosimeter

NASA Astrophysics Data System (ADS)

Junot, Danilo O.; Santos, Max A.; Chagas, Marcos A. P.; Couto dos Santos, Marcos A.; Nunes, Luiz A. O.; Souza, Divanizia N.

2014-02-01

A new composite based on CaSO4, using terbium as dopant and ytterbium as co-dopant (CaSO4:Tb,Yb), was developed for employment as a thermoluminescent (TL) dosimeter. The crystals used in this work were grown using a production route based on the Yamashita method (Yamashita et al., 1968). Crystal powder was calcined at 600 °C for 1 h. Pellets were made by adding commercial and colorless glass to improve physical resistance and sintered at 700 °C for 6 h. All samples were irradiated by a beta source (90Sr/90Y) and received doses from 1 Gy to 5 Gy. TL analyses have been performed and characteristics such as sensitivity, reproducibility, linearity, and fading have been studied. The CaSO4:Tb,Yb pellets glow curves presented two peaks, the first at around 115 °C, and the second at around 200 °C. The highest intensity was shown for CaSO4:Tb,Yb with a concentration of 0.1 mol% of Tb and Yb together. In all the samples the TL response was proportional to the absorbed dose. Therefore, the CaSO4:Tb,Yb has potential to be used as a thermoluminescent dosimeter.

Effects of porous media preparation on bacteria transport through laboratory columns.

PubMed

Brown, Derick G; Stencel, Joseph R; Jaffé, Peter R

2002-01-01

Bacterial and colloid transport experiments related to environmental systems are typically performed in the laboratory, with sand often used as the porous media. In order to prepare the sand, mechanical sieving is frequently used to tighten the sand grain size distribution. However, mechanical sieving has been reported to provide insufficient repeatability between identical colloidal transport experiments. This work examined the deficiencies of mechanical sieving with respect to bacterial transport through sand columns. It was found that sieving with standard brass sieves (1) contaminates the sand with copper and zinc as a linear function of sieving time and (2) inefficiently sizes sand grains below 300 microm (the largest size examined in this study) due to rapid clogging of the sieves. A procedure was developed that allows utilization of brass sieves for sizing the sand grains and removes the metal contamination introduced from the sieves. Bacterial transport experiments utilizing this column preparation procedure gave repeatable breakthrough curves. Further examination of the effects of these treatments on bacterial transport showed interesting results. First, it was found that the metal contamination did not affect the clean-bed bacterial transport. Second. it was found that variations of the column flushing procedure did not alter the clean-bed breakthrough of the bacteria, but did alter the inter-particle blocking. Finally, it was found that the shape of the sand grains (oblong vs. rounded) significantly alters the bacterial transport. with the transport being dominated by the smallest dimension of the oblong grains.

Cu+ emission in Li2BPO5 material for thermoluminescence dosimetry

NASA Astrophysics Data System (ADS)

Puppalwar, S. P.; Dhoble, S. J.; Kumar, Animesh

2012-05-01

In this study, Li2BPO5 doped with Cu and that co-doped with Mg are synthesized by the wet chemical technique and exposed to γ rays of 60Co to determine their thermoluminescence (TL) properties. The X-ray diffraction technique shows the crystalline nature of the prepared material. The photoluminescence (PL) emission spectra of Li2BPO5:Cu phosphor show the strong prominent peak at 368 nm in the violet region of the visible spectrum due to the transition of 3d94s1 ↔ 3d10 of monovalent copper ion. The PL emission of Li2BPO5:Cu is enhanced by the addition of Mg. The TL glow curves of γ-irradiated Li2BPO5:Cu sample show one glow peak at 143°C, indicating that only one set of traps is being activated within the particular temperature range each with its own value of activation energy (E) and frequency factor (s). The trapping parameters associated with the prominent glow peak of Li2BPO5:Cu are calculated using the glow curve shape (Chen's) method. The release of hole/electron from defect centers at the characteristic trap site initiates the luminescence process in these materials. A linear TL response is observed in Li2BPO5:Cu in a long span of exposures. The sensitivity of Li2BPO5:Cu sample is observed to be 7.8 times that of (TLD-100) LiF:Mg, Ti.

A One-Pot Self-Assembly Reaction to Prepare a Supramolecular Palladium(II) Cyclometalated Complex: An Undergraduate Organometallic Laboratory Experiment

ERIC Educational Resources Information Center

Fernandez, Alberto; Lopez-Torres, Margarita; Fernandez, Jesus J.; Vazquez-Garcia, Digna; Vila, Jose M.

2012-01-01

A laboratory experiment for students in advanced inorganic chemistry is described. Students prepare palladium(II) cyclometalated complexes. A terdentate [C,N,O] Schiff base ligand is doubly deprotonated upon reaction with palladium(II) acetate in a self-assembly process to give a palladacycle with a characteristic tetranuclear structure. This…

Organic Laboratory Experiments.

ERIC Educational Resources Information Center

Smith, Sherrel

1990-01-01

Detailed is a method in which short pieces of teflon tubing may be used for collection tubes for collecting preparative fractions from gas chromatographs. Material preparation, laboratory procedures, and results of this method are discussed. (CW)

Positional glow curve simulation for thermoluminescent detector (TLD) system design

NASA Astrophysics Data System (ADS)

Branch, C. J.; Kearfott, K. J.

1999-02-01

Multi- and thin element dosimeters, variable heating rate schemes, and glow-curve analysis have been employed to improve environmental and personnel dosimetry using thermoluminescent detectors (TLDs). Detailed analysis of the effects of errors and optimization of techniques would be highly desirable. However, an understanding of the relationship between TL light production, light attenuation, and precise heating schemes is made difficult because of experimental challenges involved in measuring positional TL light production and temperature variations as a function of time. This work reports the development of a general-purpose computer code, thermoluminescent detector simulator, TLD-SIM, to simulate the heating of any TLD type using a variety of conventional and experimental heating methods including pulsed focused or unfocused lasers with Gaussian or uniform cross sections, planchet, hot gas, hot finger, optical, infrared, or electrical heating. TLD-SIM has been used to study the impact on the TL light production of varying the input parameters which include: detector composition, heat capacity, heat conductivity, physical size, and density; trapped electron density, the frequency factor of oscillation of electrons in the traps, and trap-conduction band potential energy difference; heating scheme source terms and heat transfer boundary conditions; and TL light scatter and attenuation coefficients. Temperature profiles and glow curves as a function of position time, as well as the corresponding temporally and/or spatially integrated glow values, may be plotted while varying any of the input parameters. Examples illustrating TLD system functions, including glow curve variability, will be presented. The flexible capabilities of TLD-SIM promises to enable improved TLD system design.

Neutron Activation Foil and Thermoluminescent Dosimeter Responses to a Polyethylene Reflected Pulse of the CEA Valduc SILENE Critical Assembly

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

Miller, Thomas Martin; Celik, Cihangir; McMahan, Kimberly L.

This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 19, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). Themore » goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. The CIDAS detects gammas with a Geiger-Muller tube and the Rocky Flats detects neutrons via charged particles produced in a thin 6LiF disc depositing energy in a Si solid state detector. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.« less

Neutron Activation Foil and Thermoluminescent Dosimeter Responses to a Lead Reflected Pulse of the CEA Valduc SILENE Critical Assembly

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

Miller, Thomas Martin; Celik, Cihangir; Isbell, Kimberly McMahan

This benchmark experiment was conducted as a joint venture between the US Department of Energy (DOE) and the French Commissariat à l'Energie Atomique (CEA). Staff at the Oak Ridge National Laboratory (ORNL) in the US and the Centre de Valduc in France planned this experiment. The experiment was conducted on October 13, 2010 in the SILENE critical assembly facility at Valduc. Several other organizations contributed to this experiment and the subsequent evaluation, including CEA Saclay, Lawrence Livermore National Laboratory (LLNL), the Y-12 National Security Complex (NSC), Babcock International Group in the United Kingdom, and Los Alamos National Laboratory (LANL). Themore » goal of this experiment was to measure neutron activation and thermoluminescent dosimeter (TLD) doses from a source similar to a fissile solution critical excursion. The resulting benchmark can be used for validation of computer codes and nuclear data libraries as required when performing analysis of criticality accident alarm systems (CAASs). A secondary goal of this experiment was to qualitatively test performance of two CAAS detectors similar to those currently and formerly in use in some US DOE facilities. The detectors tested were the CIDAS MkX and the Rocky Flats NCD-91. The CIDAS detects gammas with a Geiger-Muller tube, and the Rocky Flats detects neutrons via charged particles produced in a thin 6LiF disc, depositing energy in a Si solid-state detector. These detectors were being evaluated to determine whether they would alarm, so they were not expected to generate benchmark quality data.« less

Fire and Ice: Thermoluminescent Temperature Sensing in High-Explosive Detonations and Optical Characterization Methods for Glacier Ice Boreholes

NASA Astrophysics Data System (ADS)

Mah, Merlin Lyn

The environment around a detonating high explosive is incredibly energetic and dynamic, generating shock waves, turbulent mixing, chemical reactions, and temperature excursions of thousands of Kelvin. Probing this violent but short-lived phenomena requires durable sensors with fast response times. By contrast, the glacier ice sheets of Antarctica and Greenland change on geologic time scales; the accumulation and compression of snow into ice preserves samples of atmospheric gas, dust, and volcanic ash, while the crystal orientations of the ice reflect its conditions and movement over hundreds of thousands of years. Here, difficulty of characterization stems primarily from the location, scale, and depth of the ice sheet. This work describes new sensing technologies for both of these environments. Microparticles of thermoluminescent materials are proposed as high-survivability, bulk-deployable temperature sensors for applications such as assessing bioagent inactivation. A technique to reconstruct thermal history from subsequent thermoluminescence observations is described. MEMS devices were designed and fabricated to assist in non-detonation testing: large-area electrostatic membrane actuators were used to apply mechanical stress to thermoluminescent Y2O3 :Tb thin film, and microheaters impose rapid temperature excursions upon particles of Mg2SiO4:Tb,Co to demonstrate predictable thermoluminescent response. Closed- and open-chamber explosive detonation tests using dosimetric LiF:Mg,Ti and two experimental thermometry materials were performed to test survivability and attempt thermal event reconstruction. Two borehole logging devices are described for optical characterization of glacier ice. For detecting and recording layers of volcanic ash in glacier ice, we developed a lightweight, compact probe which uses optical fibers and purely passive downhole components to detect single-scattered long-wavelength light. To characterize ice fabric orientation, we propose a

Hydrothermally synthesized barium fluoride nanocubes for thermoluminescence dosimetry

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

Bhadane, Mahesh S.; Dahiwale, S. S.; Bhoraskar, V. N.

2016-05-23

In this work, we report a hydrothermally synthesized Dy doped BaF{sub 2} (BaF{sub 2}:Dy) nanocubes and its Thermoluminescence studies. The synthesized BaF{sub 2}:Dy samples was found to posses FCC structure and having average size ~ 60-70 nm, as revealed through X-Ray Diffraction. Cubical morphology having size ~90 nm was observed from TEM analysis. The {sup 60}Co γ- ray irradiated BaF{sub 2}:Dy TL dosimetric experiments shows a pre-dominant single glow peak at 153 °C, indicating a single level trap present as a metastable state. Furthermore, BaF{sub 2}:Dy nanophosphor shows a sharp linear response from 10 Gy to 3 kGy, thus it can be applicablemore » as a gamma dosimeter.« less

Investigation and Implementation of Commercially Available Optically Stimulated Luminescence Dosimeters for Use in Fixed Nuclear Accident Dosimeter Systems.

PubMed

Georgeson, David L; Christiansen, Byron H

2018-06-01

Idaho National Laboratory transitioned from an external dosimetry system reliant on thermoluminescent dosimeters to one that uses optically stimulated luminescence dosimeters in 2010. This change not only affected the dosimeters worn by personnel, but those found in the nuclear-accident dosimeters used across Idaho National Laboratory. The elimination of on-site use and processing of thermoluminescent dosimeters impacted Idaho National Laboratory's ability to process nuclear-accident dosimeters in a timely manner. This change in processes drove Idaho National Laboratory to develop an alternative method for fixed nuclear-accident dosimeter gamma-dose analyses. This new method was driven by the need to establish a simple, cost-effective, and rapid-turnaround alternative to the thermoluminescent-dosimeter-based fixed nuclear-accident dosimeter system. An adaptation of existing technologies proved to be the most efficient path to this end. The purpose of this article is to delineate the technical basis for replacing the thermoluminescent dosimeter contained within the Idaho National Laboratory fixed nuclear-accident dosimeter system with optically stimulated luminescence-based Landauer, Inc., nanoDot dosimeters.

Thermoluminescence of contaminating minerals for the detection of radiation treatment of dried fruits

NASA Astrophysics Data System (ADS)

Khan, H. M.; Bhatti, Ijaz A.; Delincée, Henry

2002-03-01

Several types of dry fruits (pistachio nut, dried apricot, almond and raisins) have been investigated for detection of their radiation treatment by gamma rays or electron beam using thermoluminescence (TL) measurements. These samples were irradiated to 1.0-3.0 kGy (gamma rays) or 0.75-3.9 kGy (10 MeV electron beam). Thermoluminescence glow curves for the contaminating minerals separated from the dry fruits were recorded between the temperature range of 50°C and 500°C. In all the cases, the intensity of TL signal for the irradiated dry fruits was 1-3 orders of magnitudes higher than the TL intensity of the corresponding unirradiated control samples allowing clear distinction between the irradiated and unirradiated samples. These results were normalized by re-irradiating the mineral grains with a gamma-ray dose of 1.0 kGy, and a second glow curve was recorded. The ratio of intensity of the first glow curve (TL 1) to that after the normalization dose (TL 2), i.e. (TL 1/TL 2) was determined and compared with the recommended threshold values. These parameters, together with comparison of the shape of the first glow curve, gave unequivocal results about the radiation treatment of the dry fruit samples.

Dating of ancient Egyptian pottery using the thermoluminescence technique

NASA Astrophysics Data System (ADS)

El-Fiki, S. A.; Abdel-Wahab, M. S.; El-Faramawy, N.; El-Fiki, M. A.

1994-10-01

In the course of the dating of Egyptian ancient pottery, pottery sherds were collected from three archaeological tombs in the Nazlet El Samman region in the Giza zone (Egypt). The annual dose was measured by the gamma spectroscopic technique as well as thermoluminescence (TL) measurements. The annual dose results obtained using both methods are in quite good agreement with a consistency of 99.69%. The extracted quartz exhibited TL dating peaks at about (305 ± 5)°C and (375 ± 5)°C. The TL dating result is 4301 ± 100 which belongs to the "fourth dynasty" in the Old Kingdom. The obtained ages show that the uncertainties in TL dating using the additive method are much lower than that of archaeologists.

Neodymium oxide: A new thermoluminescent material for gamma dosimetry

NASA Astrophysics Data System (ADS)

Soliman, C.

2006-10-01

In the present study thermoluminescence (TL) glow curves of commercial and gamma (0.001 Gy to 100 kGy) exposed neodymium oxide (Nd 2O 3) have been investigated. The commercial glow curve is simple with TL peaks at 310, 350 and 385 °C. The TL sensitivity was enhanced to ˜4.7 times the original value when the investigated material was subject to pre-heating treatment at 800 °C for 1 h. The effect of storage time at room temperature has been monitored for different γ-doses. The combination of good γ-dose response and high stability of defects offer the possibility of applying the investigated material to γ-ray dosimetry in radiotherapy and experimental radiology range.

Synthesis and Thermoluminescence of ZnS:Mn2+ Nanoparticles

NASA Astrophysics Data System (ADS)

Zahedifar, M.; Taghavinia, N.; Aminpour, M.

2007-08-01

The controlled chemical method has been used for synthesis of Mn doped ZnS nanoparticles. Optical absorption studies showed that increasing of surfactant density, from 0.0001 to 0.5 mol/lit., causes the size of nanoparticles to decrease from 4.8 nm to about 3 nm and the band gap width to increase from 4.15 to 4.50 eV. Also increasing the temperature during the synthesis process caused the nanoparticle size to be increased. As a new result we observed a thermoluminescence (TL) glow peak at about 475 K, with its intensity depending on concentration of the Mn dopant. Activation energy of this glow peak was obtained to be about 0.6eV. A discussion of the obtained results is also presented.

Methods for routine control of irradiated food: Determination of the irradiation status of shellfish by thermoluminescence analysis

NASA Astrophysics Data System (ADS)

Schreiber, G. A.; Hoffmann, A.; Helle, N.; Bögl, K. W.

1994-06-01

In some countries, clearance has been given for treating certain types of shellfish by ionizing radiation in order to increase the shelf-life and to reduce health hazards which might be caused by contaminating microorganisms. In the present study, thermoluminescence (TL) analysis was used to examine the irradiation status of shellfish products purchased from local suppliers. For analysis minerals were isolated from the guts of the animals. Although on none of the examined products an irradiation treatment prior to analysis could be shown, the results obtained on non-irradiated and irradiated products have revealed that irradiation within the commercially used dose range can clearly be detected. Already first glow TL intensities of minerald indicated irradiation treatments. Normalized TL signals of non-irradiated and irradiated samples were clearly separated. By calculation of differences of TL intensities and TL signals between non-irradiated and irradiated samples in dependency of integration temperature an optimized integration area for glow curves was determined. The result of this study agree well with results obtained by two large-scale intercomparisons between food control laboratories to detect irradiation treatment of spices and herbal products as well as of fruit and vegetables by TL analysis of contaminating minerals.

Thermoluminescence of the Films, Nanocomposites, and Solutions of the Silicon Organic Polymer Poly(di- n-hexyl silane)

NASA Astrophysics Data System (ADS)

Ostapenko, N. I.; Kerita, O. A.; Ostapenko, Yu. V.

2018-03-01

A comparative study of low-temperature thermoluminescence (5-120 K) of silicon organic polymer poly(di-n-hexyl silane) films, nanocomposites (when the polymer is introduced into nanopores of silica MCM-41 and SBA-15 with diameter of pores 2.8 and 10 nm) as well as solutions of polymer in tetrahydrofuran with different concentrations from 10-3 to 10-5 mol/L was carried out. It was shown that it is possible to control the number of charge carrier traps, as well as their energy distribution by changing the diameter of silica nanopores. It is established that maxima and FWHMs of the thermoluminescence curves of nanocomposites significantly depend on the pore diameter of the nanoporous silica. This result agrees with the data obtained in the investigation of polymer solutions. In the nanocomposite with a minimum pore diameter (2.8 nm), the number and depth of the traps as well as dispersion of their energy are significantly reduced compared to their values in the polymer film.

On the use of LiF:Mg,Ti thermoluminescence dosemeters in space--a critical review.

PubMed

Horowitz, Y S; Satinger, D; Fuks, E; Oster, L; Podpalov, L

2003-01-01

The use of LiF:Mg,Ti thermoluminescence dosemeters (TLDs) in space radiation fields is reviewed. It is demonstrated in the context of modified track structure theory and microdosimetric track structure theory that there is no unique correlation between the relative thermoluminescence (TL) efficiency of heavy charged particles, neutrons of all energies and linear energy transfer (LET). Many experimental measurements dating back more than two decades also demonstrate the multivalued, non-universal, relationship between relative TL efficiency and LET. It is further demonstrated that the relative intensities of the dosimetric peaks and especially the high-temperature structure are dependent on a large number of variables, some controllable, some not. It is concluded that TL techniques employing the concept of LET (e.g. measurement of total dose, the high-temperature ratio (HTR) methods and other combinations of the relative TL efficiency of the various peaks used to estimate average Q or simulate Q-LET relationships) should be regarded as lacking a sound theoretical basis, highly prone to error and, as well, lack of reproducibility/universality due to the absence of a standardised experimental protocol essential to reliable experimental methodology.

Radioluminescence as a function of temperature and low temperature thermoluminescence of BaY2F8:Ce and BaY2F8:Nd crystals

NASA Astrophysics Data System (ADS)

Kowalski, Z.; Kaczmarek, S. M.; Brylew, K.; Drozdowski, W.

2016-09-01

Radioluminescence spectra at temperatures ranging from 10 to 320 K and low temperature thermoluminescence glow curves of BaY2F8:Ce and BaY2F8:Nd scintillator crystals have been investigated. In both materials the intensities of the excitonic and the activator ion's emission at X-ray excitation vary with temperature, anticorrelating with each other, which provides valuable information on the host-to-ion energy transfer. Detailed thermoluminescence studies, in turn, prove the existence of charge traps, which introduce quasi-continuous distributions of energy levels into the bandgap.

Guidelines to Language Teaching in Classroom and Laboratory.

ERIC Educational Resources Information Center

Iodice, Don R.

Guidelines for evaluating, establishing, and administrating classroom and laboratory language programs are offered in this report. Attention is focused on the language laboratory, with sections on its use, scheduling, materials and texts, preparation of audio materials, preparation of tests, supervision, discipline, and maintenance. Briefer…

New 2-D dosimetric technique for radiotherapy based on planar thermoluminescent detectors.

PubMed

Olko, P; Marczewska, B; Czopyk, L; Czermak, M A; Klosowski, M; Waligórski, M P R

2006-01-01

At the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ) in Kraków, a two-dimensional (2-D) thermoluminescence (TL) dosimetry system was developed within the MAESTRO (Methods and Advanced Equipment for Simulation and Treatment in Radio-Oncology) 6 Framework Programme and tested by evaluating 2-D dose distributions around radioactive sources. A thermoluminescent detector (TLD) foil was developed, of thickness 0.3 mm and diameter 60 mm, containing a mixture of highly sensitive LiF:Mg,Cu,P powder and Ethylene TetraFluoroEthylene (ETFE) polymer. Foil detectors were irradiated with (226)Ra brachytherapy sources and a (90)Sr/(90)Y source. 2-D dose distributions were evaluated using a prototype planar (diameter 60 mm) reader, equipped with a 12 bit Charge Coupled Devices (CCD) PCO AG camera, with a resolution of 640 x 480 pixels. The new detectors, showing a spatial resolution better than 0.5 mm and a measurable dose range typical for radiotherapy, can find many applications in clinical dosimetry. Another technology applicable to clinical dosimetry, also developed at IFJ, is the Si microstrip detector of size 95 x 95 mm(2), which may be used to evaluate the dose distribution with a spatial resolution of 120 microm along one direction, in real-time mode. The microstrip and TLD technology will be further improved, especially to develop detectors of larger area, and to make them applicable to some advanced radiotherapy modalities, such as intensity modulated radiotherapy (IMRT) or proton radiotherapy.

Teaching laboratory neuroscience at bowdoin: the laboratory instructor perspective.

PubMed

Hauptman, Stephen; Curtis, Nancy

2009-01-01

Bowdoin College is a small liberal arts college that offers a comprehensive Neuroscience major. The laboratory experience is an integral part of the major, and many students progress through three stages. A core course offers a survey of concepts and techniques. Four upper-level courses function to give students more intensive laboratory research experience in neurophysiology, molecular neurobiology, social behavior, and learning and memory. Finally, many majors choose to work in the individual research labs of the Neuroscience faculty. We, as laboratory instructors, are vital to the process, and are actively involved in all aspects of the lab-based courses. We provide student instruction in state of the art techniques in neuroscience research. By sharing laboratory teaching responsibilities with course professors, we help to prepare students for careers in laboratory neuroscience and also support and facilitate faculty research programs.

Spectral multivariate calibration without laboratory prepared or determined reference analyte values.

PubMed

Ottaway, Josh; Farrell, Jeremy A; Kalivas, John H

2013-02-05

An essential part to calibration is establishing the analyte calibration reference samples. These samples must characterize the sample matrix and measurement conditions (chemical, physical, instrumental, and environmental) of any sample to be predicted. Calibration usually requires measuring spectra for numerous reference samples in addition to determining the corresponding analyte reference values. Both tasks are typically time-consuming and costly. This paper reports on a method named pure component Tikhonov regularization (PCTR) that does not require laboratory prepared or determined reference values. Instead, an analyte pure component spectrum is used in conjunction with nonanalyte spectra for calibration. Nonanalyte spectra can be from different sources including pure component interference samples, blanks, and constant analyte samples. The approach is also applicable to calibration maintenance when the analyte pure component spectrum is measured in one set of conditions and nonanalyte spectra are measured in new conditions. The PCTR method balances the trade-offs between calibration model shrinkage and the degree of orthogonality to the nonanalyte content (model direction) in order to obtain accurate predictions. Using visible and near-infrared (NIR) spectral data sets, the PCTR results are comparable to those obtained using ridge regression (RR) with reference calibration sets. The flexibility of PCTR also allows including reference samples if such samples are available.

Detection of ionizing radiations by studying ceramic tiles materials using thermoluminescence technique

NASA Astrophysics Data System (ADS)

Mandavia, H. C.; Murthy, K. V. R.; Purohit, R. U.

2017-05-01

Natural background radiation comes from two primary sources: cosmic radiation and terrestrial sources. Our natural environment has both livings and non-livings like - Sun, Moon, Sky, Air, Water, Soil, Rivers, Mountains, Forests, besides plants and animals. The worldwide average background dose for a human being is about 2.4 millisievert (mSv) per year. This exposure is mostly from cosmic radiation and natural radionuclides in the environment. The Earth, and all living things on it, are constantly bombarded by radiation from outer space. This radiation primarily consists of positively charged ions from protons to iron and larger nuclei derived sources outside our solar system. This radiation interacts with atoms in the atmosphere to create secondary radiation, including X-rays, muons, protons, alpha particles, pions, electrons, and neutrons. The present study discusses the utility of ceramic tiles as radiation dosimeters in case of nuclear fallout. Many flooring materials most of them are in natural form are used to manufacture floor tiles for household flooring purpose. Many natural minerals are used as the raw materials required for the manufacturing ceramic ware. The following minerals are used to manufacturing the ceramic tiles i.e. Quartz, Feldspar, Zircon, Talc, Grog, Alumina oxide, etc. Most of the minerals are from Indian mines of Gujarat and Rajasthan states, some of are imported from Russian subcontinent. The present paper reports the thermoluminescence dosimetry Study of Feldspar and Quartz minerals collected from the ceramic tiles manufacturing unit, Morbi. The main basis in the Thermoluminescence Dosimetry (TLD) is that TL output is directly proportional to the radiation dose received by the phosphor and hence provides the means of estimating unknown radiations from environment.

Evaluation of dose variation during total skin electron irradiation using thermoluminescent dosimeters.

PubMed

Weaver, R D; Gerbi, B J; Dusenbery, K E

1995-09-30

To determine acceptable dose variation using thermoluminescent dosimeters (TLD) in the treatment of Mycosis Fungoides with total skin electron beam (TSEB) irradiation. From 1983 to 1993, 22 patients were treated with total skin electron beam therapy in the standing position. A six-field technique was used to deliver 2 Gy in two days, treating 4 days per week, to a total dose of 35 to 40 Gy using a degraded 9 MeV electron beam. Thermoluminescent dosimeters were placed on several locations of the body and the results recorded. The variations in these readings were analyzed to determine normal dose variation for various body locations during TSEB. The dose to flat surfaces of the body was essentially the same as the dose to the prescription point. The dose to tangential surfaces was within +/- 10% of the prescription dose, but the readings showed much more variation (up to 24%). Thin areas of the body showed large deviations from the prescription dose along with a large amount of variation in the readings (up to 22%). Special areas of the body, such as the perineum and eyelid, showed large deviations from the prescription dose with very large (up to 40%) variations in the readings. The TLD results of this study will be used as a quality assurance check for all new patients treated with TSEB. The results of the TLDs will be compared with this baseline study to determine if the delivered dose is within acceptable ranges. If the TLD results fall outside the acceptable limits established above, then the patient position can be modified or the technique itself evaluated.

Fossil track and thermoluminescence studies of Luna 20 material.

NASA Technical Reports Server (NTRS)

Crozaz, G.; Walker, R.; Zimmerman, D.

1973-01-01

Track densities in 85 feldspar crystals from L-2009 range from 2,500,000 per sq cm to greater than one billion per sq cm. This track distribution represents an intermediate case between what have been previously defined as lightly and heavily irradiated soils and suggests that the Luna 20 sample consists of a mixture of a mature, heavily irradiated component with another, lightly irradiated component. Using a two-component mixing model, the age of the lightly irradiated component is about 270,000,000 yr. It is possible, but by no means certain, that this is associated with the formation of the crater Apollonius C. At about 200 C the ratio of natural thermoluminescence to that induced by a standard irradiation is similar to that in Apollo 12 and 14 cores below about 7 cm. This confirms that most of the Luna 20 sample represents subsurface material.

Teaching about citric acid cycle using plant mitochondrial preparations: Some assays for use in laboratory courses*.

PubMed

Vicente, Joaquim A F; Gomes-Santos, Carina S S; Sousa, Ana Paula M; Madeira, Vítor M C

2005-03-01

Potato tubers and turnip roots were used to prepare purified mitochondria for laboratory practical work in the teaching of the citric acid cycle (TCA cycle). Plant mitochondria are particularly advantageous over the animal fractions to demonstrate the TCA cycle enzymatic steps, by using simple techniques to measure O(2) consumption and transmembrane potential (ΔΨ). The several TCA cycle intermediates induce specific enzyme activities, which can be identified by respiratory parameters. Such a strategy is also used to evidence properties of the TCA cycle enzymes: ADP stimulation of isocitrate dehydrogenase and α-ketoglutarate dehydrogenase; activation by citrate of downstream oxidation steps, e.g. succinate dehydrogenase; and regulation of the activity of isocitrate dehydrogenase by citrate action on the citrate/isocitrate carrier. Furthermore, it has been demonstrated that, in the absence of exogenous Mg(2+) , isocitrate-dependent respiration favors the alternative oxidase pathway, as judged by changes of the ADP/O elicited by the inhibitor n-propyl galate. These are some examples of assays related with TCA cycle intermediates we can use in laboratory courses. Copyright © 2005 International Union of Biochemistry and Molecular Biology, Inc.

Integrated Work Management: Preparer, Course 31883

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

Simpson, Lewis Edward

The preparer (also called the “planner”) plays a key role in the integrated work management (IWM) process at Los Alamos National Laboratory (LANL). This course, Integrated Work Management: Preparer (COURSE 31883), describes the IWM roles and responsibilities of the preparer. This course also discusses IWM requirements that must be met by the preparer.

Laboratory medicine: challenges and opportunities.

PubMed

Bossuyt, Xavier; Verweire, Kurt; Blanckaert, Norbert

2007-10-01

Technologic innovations have substantially improved the productivity of clinical laboratories, but the services provided by clinical laboratories are increasingly becoming commoditized. We reflect on how current developments may affect the future of laboratory medicine and how to deal with these changes. We argue that to be prepared for the future, clinical laboratories should enhance efficiency and reduce costs by forming alliances and networks; consolidating, integrating, or outsourcing; and more importantly, create additional value by providing knowledge services related to in vitro diagnostics.

BaSO4:Eu as an energy independent thermoluminescent radiation dosimeter for gamma rays and C6+ ion beam

NASA Astrophysics Data System (ADS)

Sharma, Kanika; Bahl, Shaila; Singh, Birendra; Kumar, Pratik; Lochab, S. P.; Pandey, Anant

2018-04-01

BaSO4:Eu nanophosphor is delicately optimized by varying the concentration of the impurity element and compared to the commercially available thermoluminescent dosimeter (TLD) LiF:Mg,Ti (TLD-100) and by extension also to CaSO4:Dy (TLD-900) so as to achieve its maximum thermoluminescence (TL) sensitivity. Further, the energy dependence property of this barite nanophosphor is also explored at length by exposing the phosphor with 1.25 MeV of Co-60, 0.662 MeV of Cs-137, 85 MeV and 65 MeV of Carbon ion beams. Various batches of the phosphor at hand (with impurity concentrations being 0.05, 0.10, 0.20, 0.50 and 1.00 mol%) are prepared by the chemical co-precipitation method out of which BaSO4:Eu with 0.20 mol% Eu exhibits the maximum TL sensitivity. Further, the optimized nanophosphor exhibits a whopping 28.52 times higher TL sensitivity than the commercially available TLD-100 and 1.426 times higher sensitivity than TLD-900, a noteworthy linear response curve for an exceptionally wide range of doses i.e. 10 Gy to 2 kGy and a simple glow curve structure. Furthermore, when the newly optimized nanophosphor is exposed with two different energies of gamma radiations, namely 1.25 MeV of Co-60 (dose range- 10-300 Gy) and 0.662 MeV of Cs-137 (dose range- 1-300 Gy), it is observed that the shape and structure of the glow curves remain remarkably similar for different energies of radiation while the TL response curve shows little to no variation. When exposed to different energies of carbon ion beam BaSO4:Eu displays energy independence at lower doses i.e. from 6.059 to 14.497 kGy. Finally, even though energy independence is lost at higher doses, the material shows high sensitivity to higher energy (85 MeV) of carbon beam compared to the lower energy (65 MeV of C6+) and saturation is apparent only after 121.199 kGy. Therefore the present nanophosphor displays potential as an energy independent TLD.

Materials Characterization Laboratory | Energy Systems Integration Facility

Science.gov Websites

| NREL Materials Characterization Laboratory Materials Characterization Laboratory The Energy Systems Integration Facility's Materials Characterization Laboratory supports the physical and photo -electrochemical characterization of novel materials. Photo of an NREL researcher preparing samples for a gas

Dose measurements in intraoral radiography using thermoluminescent dosimeters

NASA Astrophysics Data System (ADS)

Azorín, C.; Azorín, J.; Aguirre, F.; Rivera, T.

2015-01-01

The use of X-ray in medicine demands to expose the patient and the professional to the lowest radiation doses available in agreement with ALARA philosophy. The reference level for intraoral dental radiography is 7 mGy and, in Mexico, a number of examinations of this type are performed annually. It is considered that approximately 25% of all the X-rays examinations carried out in our country correspond to intraoral radiographies. In other hand, most of the intraoral X-ray equipment correspond to conventional radiological systems using film, which are developed as much manual as automatically. In this work the results of determining the doses received by the patients in intraoral radiological examinations made with different radiological systems using LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters are presented. In some conventional radiological systems using film, when films are developed manual or automatically, incident kerma up to 10.61 ± 0.74 mGv were determined. These values exceed that reference level suggested by the IAEA and in the Mexican standards for intraoral examinations.

Identification of a gamma-irradiated ingredient (garlic powder) in Korean barbeque sauce by thermoluminescence analysis.

PubMed

Ahn, Jae-Jun; Akram, Kashif; Lee, Jeongeun; Kim, Kyong-Su; Kwon, Joong-Ho

2012-04-01

Thermoluminescence (TL) analysis was applied to identify gamma-irradiated garlic powder in Korean barbeque sauce before and after pasteurization (85 °C, 30 min), when blended in different ratios (1%, 3%, and 5%). The sauce sample with nonirradiated garlic powder gave a background glow curve. However, the sample blended with irradiated ingredient (1 and 10 kGy) showed typical TL glow curves at temperatures of 150 to 200 °C. The identification properties of sauce samples were more influenced by blending ratios than by irradiation doses, showing that 3% and 5% added samples produced glow curves at 150 to 250 °C. After pasteurization of the samples containing the irradiated ingredient, TL glow intensity decreased but did not change its shape or temperature range. As a result, the pasteurization of Barbeque sauces containing irradiated ingredients had reduced TL glow intensity, but the shape and temperature range of glow curve were still able to provide information required for confirming irradiation treatment. To monitor the irradiated food in international market, thermoluminescence (TL) analysis is considered most promising identification technique because of its sensitivity and long-term stability. In this study the applicability of TL analysis to detect an irradiated ingredient (garlic powder) added in low quantity to a food matrix (sauce) was investigated. The effect of processing (pasteurization) on TL results was also evaluated. © 2012 Institute of Food Technologists®

Inter-laboratory comparison measurements of radiochemical laboratories in Slovakia.

PubMed

Meresová, J; Belanová, A; Vrsková, M

2010-01-01

The first inter-laboratory comparison organized by the radiochemistry laboratory of Water Research Institute (WRI) in Bratislava was carried out in 1993 and since then is it realized on an annual basis and about 10 radiochemical laboratories from all over Slovakia are participating. The gross alpha and gross beta activities, and the activity concentrations of (222)Rn, tritium, and (226)Ra, and U(nat) concentration in synthetic water samples are compared. The distributed samples are covering the concentration range prevailing in potable and surface waters and are prepared by dilution of certified reference materials. Over the course of the years 1993-2008, we observed the improvement in the quality of results for most of the laboratories. However, the success rate of the gross alpha determination activity is not improving as much as the other parameters. Copyright 2009 Elsevier Ltd. All rights reserved.

Potential of a New Technique for Remote Sensing of Hydrocarbon Accumulations and Blind Uranium Deposits: Buried Lif Thermoluminescence Dosimeters

NASA Technical Reports Server (NTRS)

Siegel, F. R.; Vaz, J. E.; Lindholm, R. C.

1982-01-01

Buried thermoluminescence dosimeters may be useful in remote sensing of petroleum and natural gas accumulations and blind uranium deposits. They act as integrating detectors that smooth out the effects of environmental variations that affect other measuring systems and result in irregularities and poor repeatability in measurements made during gas and radiometric surveys.

Uncertainty analysis of absorbed dose calculations from thermoluminescence dosimeters.

PubMed

Kirby, T H; Hanson, W F; Johnston, D A

1992-01-01

Thermoluminescence dosimeters (TLD) are widely used to verify absorbed doses delivered from radiation therapy beams. Specifically, they are used by the Radiological Physics Center for mailed dosimetry for verification of therapy machine output. The effects of the random experimental uncertainties of various factors on dose calculations from TLD signals are examined, including: fading, dose response nonlinearity, and energy response corrections; reproducibility of TL signal measurements and TLD reader calibration. Individual uncertainties are combined to estimate the total uncertainty due to random fluctuations. The Radiological Physics Center's (RPC) mail out TLD system, utilizing throwaway LiF powder to monitor high-energy photon and electron beam outputs, is analyzed in detail. The technique may also be applicable to other TLD systems. It is shown that statements of +/- 2% dose uncertainty and +/- 5% action criterion for TLD dosimetry are reasonable when related to uncertainties in the dose calculations, provided the standard deviation (s.d.) of TL readings is 1.5% or better.

A fading-based method for checking the presence of closely overlapping peaks in thermoluminescent (TL) materials

NASA Astrophysics Data System (ADS)

Furetta, C.

The paper describes a method, based on fading experiment, for determining the presence of a complex structure in the thermoluminescent glow curve emission from herbs, e.g. oregano and nopal. Because of the polymineral content of the inorganic part of these herbs, the emitted glow curve is the result of several overlapping glow peaks, each one corresponding to another mineral. The initial rise method is also used for determining the activation energy of each component.

A system for electron therapy dosimetry surveys with thermoluminescence dosimeters.

PubMed

Soares, C G; Ehrlich, M; Padikal, T N; Gromadzki, Z C

1982-11-01

Radiation-therapy dosimetry surveys employing thermoluminescence dosimeters (TLDs) are now being considered for high-energy electron beams. Using a system of individually calibrated pressed LiF TLDs in a water and a polystyrene phantom, we established that the distortions of depth-dose distributions in non-conducting materials previously observed at high absorbed doses and high dose rates were not detectable in the present geometry at doses and dose rates as much as 40 times higher than those employed in radiation therapy. The system was then used to measure TLD response in water and in polystyrene in the nominal electron-energy range from 7 to 18 MeV. In the water phantom, the well-known trend for TLD response to decrease with increasing electron energy was observed. In the polystyrene phantom, TLD response was found to be independent of electron energy.

Tips and traps in the 14C bio-AMS preparation laboratory

NASA Astrophysics Data System (ADS)

Buchholz, Bruce A.; Freeman, Stewart P. H. T.; Haack, Kurt W.; Vogel, John S.

2000-10-01

Maintaining a contamination free sample preparation lab for biological 14C AMS requires the same or more diligence as a radiocarbon dating prep lab. Isotope ratios of materials routinely range over 4-8 orders of magnitude in a single experiment, dosing solutions contain thousands of DPM and gels used to separate proteins possess 14C ratios of 1 amol 14C/mg C. Radiocarbon contamination is a legacy of earlier tracer work in most biological laboratories, even if they were never hot labs. Removable surface contamination can be found and monitored using swipes. Contamination can be found on any surface routinely touched: door knobs, light switches, drawer handles, water faucets. In general, all surfaces routinely touched need to be covered with paper, foil or plastic that can be changed frequently. Shared air supplies can also present problems by distributing hot aerosols throughout a building. Aerosols can be monitored for 14C content using graphitized coal or fullerene soot mixed with metal powder as an absorber. The monitors can be set out in work spaces for 1-2 weeks and measured by AMS with regular samples. Frequent air changes help minimize aerosol contamination in many cases. Cross-contamination of samples can be minimized by using disposable plastic or glassware in the prep lab, isolating samples from the air when possible and using positive displacement pipettors.

Chemical Preparation Laboratory for IND Candidate Compounds

DTIC Science & Technology

1989-01-31

were prepared in strict compliance with "Current Good Manufacturing Procedures" (CGMP) guidelines. All inter- mediates and final products unreported...TO U.S. ARMY MEDICAL RESARCH INSTITUTE OF INFECTIOUS DISEASES (USANRIID) JANUARY 17. 1938 TO JANUARY 16. 1989 Production N.Compound Amount Control No...RESARCH INSTITUTE OF INFECTIOUS DISEASES (USAMRIID) JANUARY 17. 1988 TO JANUARY 16. 1989. Continued Production No. Compound Amount Control No. AVS 206 l-$-D

Investigation of thermoluminescence and kinetic parameters of CaMgB{sub 2}O{sub 5}: Dy{sup 3+} nanophosphor

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

Manhas, M.; Kumar, Vinay, E-mail: vinaykumar@smvdu.ac.in; Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein ZA9300

2016-05-06

In this paper, thermoluminescence (TL) properties of Dy{sup 3+} (1.5 mol %) doped CaMgB{sub 2}O{sub 5} nanophosphor after being exposed to ultraviolet (UV) radiations (λ=254nm) were investigated. In UV exposed samples, the thermoluminescence glow curve consists of a broad glow peak located at 380 K with a small shoulder at 507 K. A shift in glow peak temperature from 367 K to 380 K after the UV exposure for 80 min was observed, which clearly shows that glow peaks follow the second order kinetics. The TL intensity of the peaks increases with an increase in the exposure time of UV rays (10-180 min). The TL Anal programmore » was used to analyze the glow curve. The kinetic parameters such as activation energy (E), the frequency factor (s) and the order of kinetics (b) were calculated for CaMgB{sub 2}O{sub 5}: Dy{sup 3+} nanophosphors.« less

Thermoluminescence Response of Ge-Doped Cylindrical-, Flat- and Photonic Crystal Silica-Fibres to Electron and Photon Radiation

PubMed Central

Entezam, A.; Khandaker, M. U.; Amin, Y. M.; Ung, N. M.; Bradley, D. A.; Maah, J.; Safari, M. J.; Moradi, F.

2016-01-01

Study has been made of the thermoluminescence (TL) response of silica-based Ge-doped cylindrical, flat and photonic crystal fibres (referred to herein as PCF-collapsed) to electron (6, 12 and 20 MeV) and photon (6, 10 MV) irradiation and 1.25 MeV γ-rays, for doses from 0.1 Gy to 100 Gy. The electron and photon irradiations were delivered through use of a Varian Model 2100C linear accelerator located at the University of Malaya Medical Centre and γ-rays delivered from a 60Co irradiator located at the Secondary Standard Dosimetry Laboratory (SSDL), Malaysian Nuclear Agency. Tailor-made to be of various dimensions and dopant concentrations (6–10% Ge), the fibres were observed to provide TL yield linear with radiation dose, reproducibility being within 1–5%, with insensitivity to energy and angular variation. The sensitivity dependency of both detectors with respect to field size follows the dependency of the output factors. For flat fibres exposed to 6 MV X-rays, the 6% Ge-doped fibre provided the greatest TL yield while PCF-collapsed showed a response 2.4 times greater than that of the 6% Ge-doped flat fibres. The response of cylindrical fibres increased with core size. The fibres offer uniform response, high spatial resolution and sensitivity, providing the basis of promising TL systems for radiotherapy applications. PMID:27149115

Diets, equipment, and techniques for maintaining crawfish in the laboratory

USGS Publications Warehouse

Tarshis, I.B.; Avault, James W.

1978-01-01

One commercial and 4 laboratory prepared extruded, water-stable diets were fed 3 times a week in 1-g portions to juvenile male and female White River crawfish, Procambarus acutus acutus (Girard), for 10 weeks. The. binding material in the laboratory preparation was alginate (Kelgin), whereas that in the commercial preparation was starch. No statistically significant weight differences developed between the groups of crawfish at the end of the 10-week period; all 5 diets were found satisfactory for feeding and maintaining P. acutus acutus in the laboratory, and all test crawfish survived throughout the experimental period. Weight gains were highest in a diet containing 50.5% protein; intermediate in those fed a diet with 46.0% protein; and lowest in those fed diets with 31.7 or 36.3% protein. Crawfish fed the commercial preparation of one of the 46.0% protein diets showed a slightly but not significantly higher weight gain than those fed the laboratory preparation of the diet. In an evaluation of the water stability of 5 commercially prepared animal chow diets and the commercial extruded diet, 2 of the commercial diets disintegrated after one hour exposure in water and the other 3 became bloated after one hour and remained on the surface throughout the 24-hour test. The commercial extruded diet maintained its water stability for the full 24 hours. The commercial preparation of the 46.0% protein diet was successfully used under laboratory conditions for feeding and maintaining the following crawfishes: Cambarellus shufeldtii (Faxon), Cambarus acuminatus Faxon, Orconectes limosus (Rafinesque), O. virilis (Hagen), Procambarus clarkii (Girard), and P. spiculifer (Le conte). In longevity experiments Cambarus diogenes diogenes Girard and Procambarus hinei (Ortmann) now have survived for 8 months on this diet in the laboratory.

ISO 15189 accreditation: Requirements for quality and competence of medical laboratories, experience of a laboratory I.

PubMed

Guzel, Omer; Guner, Ebru Ilhan

2009-03-01

Medical laboratories are the key partners in patient safety. Laboratory results influence 70% of medical diagnoses. Quality of laboratory service is the major factor which directly affects the quality of health care. The clinical laboratory as a whole has to provide the best patient care promoting excellence. International Standard ISO 15189, based upon ISO 17025 and ISO 9001 standards, provides requirements for competence and quality of medical laboratories. Accredited medical laboratories enhance credibility and competency of their testing services. Our group of laboratories, one of the leading institutions in the area, had previous experience with ISO 9001 and ISO 17025 Accreditation at non-medical sections. We started to prepared for ISO 15189 Accreditation at the beginning of 2006 and were certified in March, 2007. We spent more than a year to prepare for accreditation. Accreditation scopes of our laboratory were as follows: clinical chemistry, hematology, immunology, allergology, microbiology, parasitology, molecular biology of infection serology and transfusion medicine. The total number of accredited tests is 531. We participate in five different PT programs. Inter Laboratory Comparison (ILC) protocols are performed with reputable laboratories. 82 different PT Program modules, 277 cycles per year for 451 tests and 72 ILC program organizations for remaining tests have been performed. Our laboratory also organizes a PT program for flow cytometry. 22 laboratories participate in this program, 2 cycles per year. Our laboratory has had its own custom made WEB based LIS system since 2001. We serve more than 500 customers on a real time basis. Our quality management system is also documented and processed electronically, Document Management System (DMS), via our intranet. Preparatory phase for accreditation, data management, external quality control programs, personnel related issues before, during and after accreditation process are presented. Every laboratory has

LABORATORY DESIGN CONSIDERATIONS FOR SAFETY.

ERIC Educational Resources Information Center

National Safety Council, Chicago, IL. Campus Safety Association.

THIS SET OF CONSIDERATIONS HAS BEEN PREPARED TO PROVIDE PERSONS WORKING ON THE DESIGN OF NEW OR REMODELED LABORATORY FACILITIES WITH A SUITABLE REFERENCE GUIDE TO DESIGN SAFETY. THERE IS NO DISTINCTION BETWEEN TYPES OF LABORATORY AND THE EMPHASIS IS ON GIVING GUIDES AND ALTERNATIVES RATHER THAN DETAILED SPECIFICATIONS. AREAS COVERED INCLUDE--(1)…

Structure, photoluminescence and thermoluminescence study of a composite ZnTa2O6/ZnGa2O4 compound doped with Pr3+

NASA Astrophysics Data System (ADS)

Noto, L. L.; Shaat, S. K. K.; Poelman, D.; Dhlamini, M. S.; Mothudi, B. M.; Swart, H. C.

2016-05-01

The study of persistent luminescence is interesting for applications related to biological imaging, self-lit roads and security signs. Composite Pr-doped samples were prepared in one pot by solid chemical reaction at 1200 °C for 4 h. The X-ray diffraction patterns of the samples showed mixed phases which correspond to ZnGa2O4 and ZnTa2O6 phases. Interestingly, the secondary electron microscopy images showed that the surface morphology is composed of particles with different shapes: irregular, rhombus and rod shapes. The X-ray maps obtained using field emission scanning electron microscopy, confirmed that the irregular particles correspond to ZnTa2O6, and the rods correspond to ZnGa2O4. Red emission was observed from 1D2 → 3H4, 3P0 → 3H6, 3P0 → 3F2 and 1D2 → 3H5 transitions of Pr3+. The lifetime of the persistent luminescence was measured, and the corresponding trapping centres were investigated using thermoluminescence spectroscopy.

Identification of irradiated peppers by electron spin resonance, thermoluminescence and viscosity

NASA Astrophysics Data System (ADS)

Polónia, Isabel; Esteves, M. P.; Andrade, M. E.; Empis, J.

1995-02-01

White and black pepper purchased in local retailers were analysed by electron spin resonance (ESR), thermoluminescence (TL) and viscosimetry (VISC) in order to establish a viable method for identifying possibly irradiated peppers. Samples studied were non irradiated or irradiated in a cobalt-60 plant with the absorbed doses of 3, 5, 7 and 10 kGy. Confirming the data found in the literature TL was revealed by our results the best method to identify irradiated peppers. Nevertheless, the dose received by the samples could not be estimated. The ESR signal of irradiated peppers is similar to the spectrum of cellulose radical but very short lived at ambient temperature. The study on the alteration of viscosity of heat-treated alkaline pepper suspensions indicate that VISC is a very promising method for detection of irradiated peppers.

Laboratory Services Guide

DTIC Science & Technology

1994-10-01

dosimetry services using thermoluminescent dosimeters ( TLDs ) to meet 10 CFR 19, 20, 30-36, 40 and 70; to proNide dosimetry service for environmental...USAF Personnel Dosimetry Branch. Once it is determined that area or external dosimetry is necessary, request the number of TLDs required by FAX or letter... dosimetry , Request TLDs 2 - 4 weeks in advance and always designate a control badge. The Radiation Dosimetry Branch thanks you in advance for doing everything

A Laboratory Course in Technological Chemistry.

ERIC Educational Resources Information Center

Wiseman, P.

1986-01-01

Describes a laboratory course taught at the University of Manchester Institute of Science and Technology (United Kingdom) which focuses on the preparation, properties, and applications of end-use products of the chemical industry. Outlines laboratory experiments on dyes, fibers, herbicides, performance testing, antioxidants, and surface active…

Thermoluminescence dosimetric characteristics on cubic fluoroperovskite single crystal (KMgF3:Eu2+, Ce3+)

NASA Astrophysics Data System (ADS)

Joseph Daniel, D.; Madhusoodanan, U.; Annalakshmi, O.; Jose, M. T.; Ramasamy, P.

2015-07-01

This paper describes investigation of thermoluminescence radiation dosimetry characteristics of Eu2+ doped Potassium Magnesium Fluoride (KMgF3) single crystal co-doped with Ce3+ ions. The perovskite-like KMgF3 polycrystalline compounds were synthesized by standard solid state reaction technique. Phase purity of the synthesized compounds was analyzed by powder X-ray diffraction technique. Single crystals of KMgF3 have been grown from melt by using a vertical Bridgman-Stockbarger method. Thermoluminescence (TL) characteristics of KMgF3 samples doped with Eu2+ and Ce3+ have been studied after β-ray irradiation at room temperature. Order of kinetics (b), activation energy (E), and frequency factor (s) were determined by Chen's method and variable heating rate method. Results show that the TL glow peak of the KMgF3 samples obeys second-order kinetics. Analysis of the main dosimetric peak by using the methods mentioned above revealed that activation energy (E) is about 1.2 eV and the frequency factor (s) is in the range 1010-1011 s-1. The TL glow curve structure of the sample remained stable for higher doses of 90Sr/90Y beta source and it shows linearity up to 180 Gy. The time dependent fading behavior of the TL characteristics has also been investigated and is found to be quite stable over long time duration. The characteristic Eu2+ emissions are observed in the TL emission spectra.

[Quality Management and Quality Specifications of Laboratory Tests in Clinical Studies--Challenges in Pre-Analytical Processes in Clinical Laboratories].

PubMed

Ishibashi, Midori

2015-01-01

The cost, speed, and quality are the three important factors recently indicated by the Ministry of Health, Labour and Welfare (MHLW) for the purpose of accelerating clinical studies. Based on this background, the importance of laboratory tests is increasing, especially in the evaluation of clinical study participants' entry and safety, and drug efficacy. To assure the quality of laboratory tests, providing high-quality laboratory tests is mandatory. For providing adequate quality assurance in laboratory tests, quality control in the three fields of pre-analytical, analytical, and post-analytical processes is extremely important. There are, however, no detailed written requirements concerning specimen collection, handling, preparation, storage, and shipping. Most laboratory tests for clinical studies are performed onsite in a local laboratory; however, a part of laboratory tests is done in offsite central laboratories after specimen shipping. As factors affecting laboratory tests, individual and inter-individual variations are well-known. Besides these factors, standardizing the factors of specimen collection, handling, preparation, storage, and shipping, may improve and maintain the high quality of clinical studies in general. Furthermore, the analytical method, units, and reference interval are also important factors. It is concluded that, to overcome the problems derived from pre-analytical processes, it is necessary to standardize specimen handling in a broad sense.

Laboratory quality management system: road to accreditation and beyond.

PubMed

Wadhwa, V; Rai, S; Thukral, T; Chopra, M

2012-01-01

This review attempts to clarify the concepts of Laboratory Quality Management System (Lab QMS) for a medical testing and diagnostic laboratory in a holistic way and hopes to expand the horizon beyond quality control (QC) and quality assurance. It provides an insight on accreditation bodies and highlights a glimpse of existing laboratory practices but essentially it takes the reader through the journey of accreditation and during the course of reading and understanding this document, prepares the laboratory for the same. Some of the areas which have not been highlighted previously include: requirement for accreditation consultants, laboratory infrastructure and scope, applying for accreditation, document preparation. This section is well supported with practical illustrations and necessary tables and exhaustive details like preparation of a standard operating procedure and a quality manual. Concept of training and privileging of staff has been clarified and a few of the QC exercises have been dealt with in a novel way. Finally, a practical advice for facing an actual third party assessment and caution needed to prevent post-assessment pitfalls has been dealt with.

Crime Laboratory Proficiency Testing Research Program.

ERIC Educational Resources Information Center

Peterson, Joseph L.; And Others

A three-year research effort was conducted to design a crime laboratory proficiency testing program encompassing the United States. The objectives were to: (1) determine the feasibility of preparation and distribution of different classes of physical evidence; (2) assess the accuracy of criminalistics laboratories in the processing of selected…

'The artist's piece is already in the stone': constructing creativity in paleontology laboratories.

PubMed

Wylie, Caitlin Donahue

2015-02-01

Laboratory technicians are typically portrayed as manual workers following routine procedures to produce scientific data. However, technicians in vertebrate paleontology laboratories often describe their work in terms of creativity and artistry. Fossil specimens undergo extensive preparation--including rock removal, damage repair, and reconstruction of missing parts--to become accessible to researchers. Technicians called 'fossil preparators' choose, apply, and sometimes invent these preparation methods. They have no formal training, no standard protocols, and few publications to consult on techniques. Despite the resulting diversity of people and practices, preparators and their work are usually absent from research publications, making them 'invisible technicians' in Steven Shapin's sense. But preparators reject the view of their work as predictable or simple; in particular, many preparators value art training, the aesthetics of prepared fossils, and the process of creative problem-solving in their work. Based on interviews and participant observation and drawing from literature in science studies, sociology of work, and anthropology of craft, I ask why these technicians compare themselves with artists and how this portrayal affects scientific practice and social order in laboratories. I argue that associating artistry and creativity with their work distances preparators from ideas of unskilled technical work and technicians' low status, thus improving their social role in the laboratory community and preserving their power over laboratory practices.

Undergraduate Laboratory Module on Skin Diffusion

ERIC Educational Resources Information Center

Norman, James J.; Andrews, Samantha N.; Prausnitz, Mark R.

2011-01-01

To introduce students to an application of chemical engineering directly related to human health, we developed an experiment for the unit operations laboratory at Georgia Tech examining diffusion across cadaver skin in the context of transdermal drug delivery. In this laboratory module, students prepare mouse skin samples, set up diffusion cells…

Comment on ``heating rate effects in thermoluminescent glow-peaks''

NASA Astrophysics Data System (ADS)

Horowitz, Y.

1993-12-01

In a recent article, Kitis et al. [Nucl. Instr. and Meth. B 73 (1993) 367] discuss the effect of heating rate on three well-known thermoluminescence (TL) glow peaks; the 110°C glow peak of Norwegian quartz, the 210°C "dosimetry" glow peak of LiF:Mg,Ti (peak 5 in TLD-700) and the 250°C glow peak of natural Cap 2 : MBLE. The authors state that they focus their attention on "single, well-separated, glow peaks" in order to "test the theory", presumably charge detrapping kinetic theory. To achieve this rather elusive goal for the 210°C peak in LiF:Mg,Ti, the authors employ a 140°C/60 min post-irradiation anneal to depopulate the low temperature peaks. There is, however, substantial evidence in the TL literature over the past three decades that an anneal of this duration at elevated temperatures induces various thermally activated clustering and precipitation processes leading to trap modification and possible creation of new traps.

Photoluminescence and thermoluminescence properties of Eu2+ doped and Eu2+ ,Dy3+ co-doped Ba2 MgSi2 O7 phosphors.

PubMed

Sao, Sanjay Kumar; Brahme, Nameeta; Bisen, D P; Tiwari, Geetanjali

2016-11-01

In this work, we report the preparation, characterization, comparison and luminescence mechanisms of Eu 2 + -doped and Eu 2 + ,Dy 3 + -co-doped Ba 2 MgSi 2 O 7 (BMSO) phosphors. Prepared phosphors were synthesized via a high temperature solid-state reaction method. All prepared phosphors appeared white. The phase structure, particle size, and elemental analysis were analyzed using X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) analysis. The luminescence properties of the phosphors were investigated by thermoluminescence (TL) and photoluminescence (PL). The PL excitation and emission spectra of Ba 2 MgSi 2 O 7 :Eu 2 + showed the peak to be around 381 nm and 490 nm respectively. The PL excitation spectrum of Ba 2 MgSi 2 O 7 :Eu 2 + Dy 3 + showed the peak to be around 341 nm and 388 nm, and the emission spectrum had a broad band around 488 nm. These emissions originated from the 4f 6 5d 1 to 4f 7 transition of Eu 2 + . TL analysis revealed that the maximum TL intensity was found at 5 mol% of Eu 2 + doping in Ba 2 MgSi 2 O 7 phosphors after 15 min of ultraviolet (UV) light exposure. TL intensity was increased when Dy 3 + ions were co-doped in Ba 2 MgSi 2 O 7 :Eu 2 + and maximum TL intensity was observed for 2 mol% of Dy 3 + . TL emission spectra of Ba 1.95 MgSi 2 O 7 :0.05Eu 2 + and Ba 1.93 MgSi 2 O 7 :0.05Eu 2 + ,0.02Dy 3 + phosphors were found at 500 nm. TL intensity increased with UV exposure time up to 15 min, then decreased for the higher UV radiation dose for both Eu doping and Eu,Dy co-doping. The trap depths were calculated to be 0.54 eV for Ba 1.95 MgSi 2 O 7 :0.05Eu 2 + and 0.54 eV and 0.75 eV for Ba 1.93 MgSi 2 O 7 :0.05Eu 2 + ,0.02Dy 3 + phosphors. It was observed that co-doping with small amounts of Dy 3 + enhanced the thermoluminescence properties of Ba 2 MgSi 2 O 7 phosphor. Copyright © 2016 John Wiley & Sons, Ltd. [Correction added on 5 April 2016, after first online publication: The

Induced thermoluminescence as a method for dating recent volcanism: Hawaii County, Hawaii, USA

NASA Astrophysics Data System (ADS)

Sears, Derek W. G.; Sears, Hazel; Sehlke, Alexander; Hughes, Scott S.

2018-01-01

We have measured the induced thermoluminescence (TL) properties of fifteen samples of basalts collected from the Big Island of Hawaii in order to continue our investigation into the possible utility of this technique as a chronometer. Previous studies of basalts from Idaho have suggested the induced TL of basalts increases with age. Meteorite data suggest two possible explanations for this observation which are that (1) the initial glassy or amorphous phases crystalize with time to produce feldspar, the mineral producing the TL signal, and (2) feldspars lose Fe as they equilibrate and since Fe is a quencher of TL this would cause an increase in TL. The old basalts from Kohala (> 100 ka), which are mostly alkali basalts, have TL sensitivities 10-100 times higher than the much younger tholeiites from Kilauea and Mauna Loa (< 50 ka). The thermoluminescence of feldspars is strongly dependent on composition and when this is corrected for, using literature data, the slope of the regression line for the plot of log TL sensitivity against historic or radiometric age for the Hawaii basalts is within 2 sigma of the regression line for the analogous plot for the Idaho basalts, although the Hawaii line is much shallower (0.0015 ± 0.0012 for Hawaii cf. 0.0039 ± - 0.0014 for Idaho, 2σ uncertainties). However, the intercepts are significantly different (0.78 ± 0.18 for Hawaii cf. - 0.079 ± 0.28 for Idaho, 2σ uncertainties). These results suggest that TL sensitivity has the potential to be a means of dating volcanism in the 0-800 ka range, although the scatter in the data - especially for the < 50 ka samples - needs to be understood, and a means found for its removal, before the technique has the possibility of being practically useful.

A microfluidic device for preparing next generation DNA sequencing libraries and for automating other laboratory protocols that require one or more column chromatography steps.

PubMed

Tan, Swee Jin; Phan, Huan; Gerry, Benjamin Michael; Kuhn, Alexandre; Hong, Lewis Zuocheng; Min Ong, Yao; Poon, Polly Suk Yean; Unger, Marc Alexander; Jones, Robert C; Quake, Stephen R; Burkholder, William F

2013-01-01

Library preparation for next-generation DNA sequencing (NGS) remains a key bottleneck in the sequencing process which can be relieved through improved automation and miniaturization. We describe a microfluidic device for automating laboratory protocols that require one or more column chromatography steps and demonstrate its utility for preparing Next Generation sequencing libraries for the Illumina and Ion Torrent platforms. Sixteen different libraries can be generated simultaneously with significantly reduced reagent cost and hands-on time compared to manual library preparation. Using an appropriate column matrix and buffers, size selection can be performed on-chip following end-repair, dA tailing, and linker ligation, so that the libraries eluted from the chip are ready for sequencing. The core architecture of the device ensures uniform, reproducible column packing without user supervision and accommodates multiple routine protocol steps in any sequence, such as reagent mixing and incubation; column packing, loading, washing, elution, and regeneration; capture of eluted material for use as a substrate in a later step of the protocol; and removal of one column matrix so that two or more column matrices with different functional properties can be used in the same protocol. The microfluidic device is mounted on a plastic carrier so that reagents and products can be aliquoted and recovered using standard pipettors and liquid handling robots. The carrier-mounted device is operated using a benchtop controller that seals and operates the device with programmable temperature control, eliminating any requirement for the user to manually attach tubing or connectors. In addition to NGS library preparation, the device and controller are suitable for automating other time-consuming and error-prone laboratory protocols requiring column chromatography steps, such as chromatin immunoprecipitation.

Robotics in the Laboratory: A Generic Approach.

ERIC Educational Resources Information Center

Sharp, Robert L.; And Others

1988-01-01

Discusses the use of robotics in the analytical chemistry laboratory. Suggests using a modular setup to best use robots and laboratory space. Proposes a sample preparation system which can perform aliquot measurement, dilution, mixing, separation, and sample transfer. Recognizes attributes and shortcomings. (ML)

Thermoluminescence properties of CaO powder obtained from chicken eggshells

NASA Astrophysics Data System (ADS)

Nagabhushana, K. R.; Lokesha, H. S.; Satyanarayana Reddy, S.; Prakash, D.; Veerabhadraswamy, M.; Bhagyalakshmi, H.; Jayaramaiah, J. R.

2017-09-01

Eggshell wastage has created serious problem in disposal of the food processing industry which has been triggered the thoughts of researchers to use wasted eggshells as good source of calcium. In the present work, calcium oxide (CaO) has been synthesized by combustion process in furnace (F-CaO) and microwave oven (M-CaO) using the source of chicken eggshells. The obtained F-CaO and M-CaO are characterized by XRD, SEM with EDX and thermoluminescence (TL) technique. XRD pattern of both the samples show cubic phase with crystallite size 45-52 nm. TL glow curves are recorded for various gamma radiation dose (300-4000 Gy). Two TL glows, a small peak at 424 K and stronger peak at 597 K are observed. TL response of M-CaO is 2.67 times higher than F-CaO sample. TL kinetic parameters are calculated by computerized curve deconvolution analysis (CCDA) and discussed.

Engineering Laboratory Instruction in Virtual Environment--"eLIVE"

ERIC Educational Resources Information Center

Chaturvedi, Sushil; Prabhakaran, Ramamurthy; Yoon, Jaewan; Abdel-Salam, Tarek

2011-01-01

A novel application of web-based virtual laboratories to prepare students for physical experiments is explored in some detail. The pedagogy of supplementing physical laboratory with web-based virtual laboratories is implemented by developing a web-based tool, designated in this work as "eLIVE", an acronym for Engineering Laboratory…

Acceptance Testing of Thermoluminescent Dosimeter Holders.

PubMed

Romanyukha, Alexander; Grypp, Matthew D; Sharp, Thad J; DiRito, John N; Nelson, Martin E; Mavrogianis, Stanley T; Torres, Jeancarlo; Benevides, Luis A

2018-05-01

The U.S. Navy uses the Harshaw 8840/8841 dosimetric (DT-702/PD) system, which employs LiF:Mg,Cu,P thermoluminescent dosimeters (TLDs), developed and produced by Thermo Fisher Scientific (TFS). The dosimeter consists of four LiF:Mg,Cu,P elements, mounted in Teflon® on an aluminum card and placed in a plastic holder. The holder contains a unique filter for each chip made of copper, acrylonitrile butadiene styrene (ABS), Mylar®, and tin. For accredited dosimetry labs, the ISO/IEC 17025:2005(E) requires an acceptance procedure for all new equipment. The Naval Dosimetry Center (NDC) has developed and tested a new non-destructive procedure, which enables the verification and the evaluation of embedded filters in the holders. Testing is based on attenuation measurements of low-energy radiation transmitted through each filter in a representative sample group of holders to verify that the correct filter type and thickness are present. The measured response ratios are then compared with the expected response ratios. In addition, each element's measured response is compared to the mean response of the group. The test was designed and tested to identify significant nonconformities, such as missing copper or tin filters, double copper or double tin filters, or other nonconformities that may impact TLD response ratios. During the implementation of the developed procedure, testing revealed a holder with a double copper filter. To complete the evaluation, the impact of the nonconformities on proficiency testing was examined. The evaluation revealed failures in proficiency testing categories III and IV when these dosimeters were irradiated to high-energy betas.

[Laboratory accreditation and proficiency testing].

PubMed

Kuwa, Katsuhiko

2003-05-01

ISO/TC 212 covering clinical laboratory testing and in vitro diagnostic test systems will issue the international standard for medical laboratory quality and competence requirements, ISO 15189. This standard is based on the ISO/IEC 17025, general requirements for competence of testing and calibration laboratories and ISO 9001, quality management systems-requirements. Clinical laboratory services are essential to patient care and therefore should be available to meet the needs of all patients and clinical personnel responsible for human health care. If a laboratory seeks accreditation, it should select an accreditation body that operates according to this international standard and in a manner which takes into account the particular requirements of clinical laboratories. Proficiency testing should be available to evaluate the calibration laboratories and reference measurement laboratories in clinical medicine. Reference measurement procedures should be of precise and the analytical principle of measurement applied should ensure reliability. We should be prepared to establish a quality management system and proficiency testing in clinical laboratories.

Evaluating the intensity of fire at the Acheulian site of Gesher Benot Ya'aqov-Spatial and thermoluminescence analyses.

PubMed

Alperson-Afil, Nira; Richter, Daniel; Goren-Inbar, Naama

2017-01-01

This manuscript presents an attempt to evaluate the intensity of fire through spatial patterning and thermoluminescence methodology. Previous studies of Layer II-6 Level 2 at the Acheulian site of Gesher Benot Ya'aqov suggested that hominins differentiated their activities across space, including multiple activities around a hearth reconstructed on the basis of the distribution of burned flint artifacts. A transect of ~4 m was extended from the center of the reconstructed hearth of Level 2 to its periphery in order to examine the intensity of fire. Burned and unburned flint microartifacts were sampled along this transect. The results of earlier and current thermoluminescence (TL) analysis demonstrate a general agreement with the macroscopic determination of burning, indicating that the possibility of misinterpretation based on macroscopic observations is negligible. The TL signal from flint microartifacts close to the hearth's center shows unambiguous signs of strong heating, whereas with increasing distance from the hearth the TL signal can be interpreted as a result of decreasing temperatures and/or shorter durations of exposure to fire in addition to a decreasing number of flints showing fire damage. Our study shows that TL analysis can identify some variation in fire intensity, which allows a more precise classification of burned flint microartifacts with respect to their heating history.

Evaluating the intensity of fire at the Acheulian site of Gesher Benot Ya'aqov—Spatial and thermoluminescence analyses

PubMed Central

Richter, Daniel; Goren-Inbar, Naama

2017-01-01

This manuscript presents an attempt to evaluate the intensity of fire through spatial patterning and thermoluminescence methodology. Previous studies of Layer II-6 Level 2 at the Acheulian site of Gesher Benot Ya‘aqov suggested that hominins differentiated their activities across space, including multiple activities around a hearth reconstructed on the basis of the distribution of burned flint artifacts. A transect of ~4 m was extended from the center of the reconstructed hearth of Level 2 to its periphery in order to examine the intensity of fire. Burned and unburned flint microartifacts were sampled along this transect. The results of earlier and current thermoluminescence (TL) analysis demonstrate a general agreement with the macroscopic determination of burning, indicating that the possibility of misinterpretation based on macroscopic observations is negligible. The TL signal from flint microartifacts close to the hearth’s center shows unambiguous signs of strong heating, whereas with increasing distance from the hearth the TL signal can be interpreted as a result of decreasing temperatures and/or shorter durations of exposure to fire in addition to a decreasing number of flints showing fire damage. Our study shows that TL analysis can identify some variation in fire intensity, which allows a more precise classification of burned flint microartifacts with respect to their heating history. PMID:29145432

Synthesis of amino-functionalized silica nanoparticles for preparation of new laboratory standards

NASA Astrophysics Data System (ADS)

Alvarez-Toral, Aitor; Fernández, Beatriz; Malherbe, Julien; Claverie, Fanny; Pecheyran, Christophe; Pereiro, Rosario

2017-12-01

Platinum group elements (PGEs) are particularly interesting analytes in different fields, including environmental samples as well as high cost materials that contain them, such as for example automotive catalysts. This type of solid samples could be analysed by laser ablation (LA) coupled to ICP-MS, which allow to significantly reducing the analysis time since the time-consuming processes for sample preparation are not required. There is a considerable demand of standards with high PGEs concentration for quantification purposes, which cannot be carried out easily using LA-ICP-MS because the available standards (i.e. NIST SRM 61 × series) do not have such analytes in the same concentration range. In this paper, a new strategy is proposed for the synthesis of homogeneous laboratory standards with Pt, Pd and Rh concentrations that range from 77 μg/g of Pd up to 2035 μg/g of Rh. The proposed strategy is based on the synthesis of monodisperse amino-functionalized amorphous silica nanoparticles, which can retain metal ions. In addition to Pt, Pd and Rh, three lanthanides were also added to the nanoparticles (La, Ce, Nd). Sturdy pressed pellets can be made from the resulting nanopowder without the use of any binder. Elemental composition of standards made of nanoparticles was analysed by conventional nebulization ICP-MS and their homogeneity was successfully evaluated by LA-ICP-MS.

Preparing a Community Hospital to Manage Work-related Exposures to Infectious Agents in BioSafety Level 3 and 4 Laboratories

PubMed Central

Bloom, Marshall E.; Hoe, Nancy P.; Arminio, Thomas; Carlson, Paul; Powers, Tamara; Feldmann, Heinz; Wilson, Deborah

2010-01-01

Construction of new BioSafety Level (BSL) 3 and 4 laboratories has raised concerns regarding provision of care to exposed workers because of healthcare worker (HCW) unfamiliarity with precautions required. When the National Institutes of Health began construction of a new BSL-4 laboratory in Hamilton, Montana, USA, in 2005, they contracted with St. Patrick Hospital in Missoula, Montana, for care of those exposed. A care and isolation unit is described. We developed a training program for HCWs that emphasized the optimal use of barrier precautions and used pathogen-specific modules and simulations with mannequins and fluorescent liquids that represented infectious body fluids. The facility and training led to increased willingness among HCWs to care for patients with all types of communicable diseases. This model may be useful for other hospitals, whether they support a BSL-4 facility, are in the proximity of a BSL-3 facility, or are interested in upgrading their facilities to prepare for exotic and novel infectious diseases. PMID:20202409

Dose optimization of total or partial skin electron irradiation by thermoluminescent dosimetry.

PubMed

Schüttrumpf, Lars; Neumaier, Klement; Maihoefer, Cornelius; Niyazi, Maximilian; Ganswindt, Ute; Li, Minglun; Lang, Peter; Reiner, Michael; Belka, Claus; Corradini, Stefanie

2018-05-01

Due to the complex surface of the human body, total or partial skin irradiation using large electron fields is challenging. The aim of the present study was to quantify the magnitude of dose optimization required after the application of standard fields. Total skin electron irradiation (TSEI) was applied using the Stanford technique with six dual-fields. Patients presenting with localized lesions were treated with partial skin electron irradiation (PSEI) using large electron fields, which were individually adapted. In order to verify and validate the dose distribution, in vivo dosimetry with thermoluminescent dosimeters (TLD) was performed during the first treatment fraction to detect potential dose heterogeneity and to allow for an individual dose optimization with adjustment of the monitor units (MU). Between 1984 and 2017, a total of 58 patients were treated: 31 patients received TSEI using 12 treatment fields, while 27 patients underwent PSEI and were treated with 4-8 treatment fields. After evaluation of the dosimetric results, an individual dose optimization was necessary in 21 patients. Of these, 7 patients received TSEI (7/31). Monitor units (MU) needed to be corrected by a mean value of 117 MU (±105, range 18-290) uniformly for all 12 treatment fields, corresponding to a mean relative change of 12% of the prescribed MU. In comparison, the other 14 patients received PSEI (14/27) and the mean adjustment of monitor units was 282 MU (±144, range 59-500) to single or multiple fields, corresponding to a mean relative change of 22% of the prescribed MU. A second dose optimization to obtain a satisfying dose at the prescription point was need in 5 patients. Thermoluminescent dosimetry allows an individual dose optimization in TSEI and PSEI to enable a reliable adjustment of the MUs to obtain the prescription dose. Especially in PSEI in vivo dosimetry is of fundamental importance.

Preparation and Certification of Two New Bulk Welding Fume Reference Materials for Use in Laboratories Undertaking Analysis of Occupational Hygiene Samples

PubMed Central

Butler, Owen; Musgrove, Darren; Stacey, Peter

2014-01-01

Workers can be exposed to fume, arising from welding activities, which contain toxic metals and metalloids. Occupational hygienists need to assess and ultimately minimize such exposure risks. The monitoring of the concentration of particles in workplace air is one assessment approach whereby fume, from representative welding activities, is sampled onto a filter and returned to a laboratory for analysis. Inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry are generally employed as instrumental techniques of choice for the analysis of such filter samples. An inherent difficulty, however, with inductively coupled plasma-based analytical techniques is that they typically require a sample to be presented for analysis in the form of a solution. The efficiency of the required dissolution step relies heavily upon the skill and experience of the analyst involved. A useful tool in assessing the efficacy of this dissolution step would be the availability and subsequent analysis of welding fume reference materials with stated elemental concentrations and matrices that match as closely as possible the matrix composition of welding fume samples submitted to laboratories for analysis. This article describes work undertaken at the Health and Safety Laboratory to prepare and certify two new bulk welding fume reference materials that can be routinely used by analysts to assess the performance of the digestion procedures they employ in their laboratories. PMID:24499055

Preparation and certification of two new bulk welding fume reference materials for use in laboratories undertaking analysis of occupational hygiene samples.

PubMed

Butler, Owen; Musgrove, Darren; Stacey, Peter

2014-01-01

Workers can be exposed to fume, arising from welding activities, which contain toxic metals and metalloids. Occupational hygienists need to assess and ultimately minimize such exposure risks. The monitoring of the concentration of particles in workplace air is one assessment approach whereby fume, from representative welding activities, is sampled onto a filter and returned to a laboratory for analysis. Inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry are generally employed as instrumental techniques of choice for the analysis of such filter samples. An inherent difficulty, however, with inductively coupled plasma-based analytical techniques is that they typically require a sample to be presented for analysis in the form of a solution. The efficiency of the required dissolution step relies heavily upon the skill and experience of the analyst involved. A useful tool in assessing the efficacy of this dissolution step would be the availability and subsequent analysis of welding fume reference materials with stated elemental concentrations and matrices that match as closely as possible the matrix composition of welding fume samples submitted to laboratories for analysis. This article describes work undertaken at the Health and Safety Laboratory to prepare and certify two new bulk welding fume reference materials that can be routinely used by analysts to assess the performance of the digestion procedures they employ in their laboratories.

Roles of laboratories and laboratory systems in effective tuberculosis programmes.

PubMed

Ridderhof, John C; van Deun, Armand; Kam, Kai Man; Narayanan, P R; Aziz, Mohamed Abdul

2007-05-01

Laboratories and laboratory networks are a fundamental component of tuberculosis (TB) control, providing testing for diagnosis, surveillance and treatment monitoring at every level of the health-care system. New initiatives and resources to strengthen laboratory capacity and implement rapid and new diagnostic tests for TB will require recognition that laboratories are systems that require quality standards, appropriate human resources, and attention to safety in addition to supplies and equipment. To prepare the laboratory networks for new diagnostics and expanded capacity, we need to focus efforts on strengthening quality management systems (QMS) through additional resources for external quality assessment programmes for microscopy, culture, drug susceptibility testing (DST) and molecular diagnostics. QMS should also promote development of accreditation programmes to ensure adherence to standards to improve both the quality and credibility of the laboratory system within TB programmes. Corresponding attention must be given to addressing human resources at every level of the laboratory, with special consideration being given to new programmes for laboratory management and leadership skills. Strengthening laboratory networks will also involve setting up partnerships between TB programmes and those seeking to control other diseases in order to pool resources and to promote advocacy for quality standards, to develop strategies to integrate laboratories functions and to extend control programme activities to the private sector. Improving the laboratory system will assure that increased resources, in the form of supplies, equipment and facilities, will be invested in networks that are capable of providing effective testing to meet the goals of the Global Plan to Stop TB.

Electron-Beam-Pinch Experiment at Harry Diamond Laboratories: Providing for a High-Dose-Rate Flash X-Ray Facility for Transient Radiation Effects on Electronics (TREE) Testing of Pieceparts

DTIC Science & Technology

1991-08-01

The outer perimeter of the converter was attached to the C ring with copper tape. Thermoluminescent dosimeters ( TLDs )* and a coaxial x-ray diode...CaF2) TLDs in Al pillboxes for electronic equilibrium. 7 Figure 2. HIFX beam 400 pinch at 0.05 Torr, Y4 38o in. from face. _360O E 340 d 320 - .~. 300...AD-A239 558Hu D L M-91 -111, 1𔃻, 1 ,11I Aucr,, 1991 Electron -Beam-Pinch Experiment at Harry Diamond Laboratories: Providing for a High-Dose-Rate

Test Preparation: Your Role

MedlinePlus

... transport the sample from home to the lab. Examples of some common laboratory tests that require advance preparation include: Glucose tolerance, fasting, and two-hour post-prandial blood glucose tests : fasting or eating meals ...

Simulating Laboratory Procedures.

ERIC Educational Resources Information Center

Baker, J. E.; And Others

1986-01-01

Describes the use of computer assisted instruction in a medical microbiology course. Presents examples of how computer assisted instruction can present case histories in which the laboratory procedures are simulated. Discusses an authoring system used to prepare computer simulations and provides one example of a case history dealing with fractured…

Long-term preservation of chilled canine semen: effect of commercial and laboratory prepared extenders.

PubMed

Iguer-ouada, M; Verstegen, J P

2001-01-15

The present study was conducted to evaluate chilled semen conservation over time in 3 commercial and 4 laboratory prepared extenders, including a new Tris-glucose extender. The beneficial effect of adding egg yolk to these media was also analyzed. The effects of these extenders on motility and acrosome reaction were characterized objectively using a computer-aided semen analyzer and the chlortetracycline staining, respectively. No significant differences were observed when comparing the different commercial extenders without egg yolk, but addition of egg yolk improved all motility parameters significantly (preservation of 50% of motility was observed at 3.2+/-1, 2.9+/-0.5, 2.3+/-0.5, 8.5+/-0.2, 5.4+/-1.1, 5.2+/-0.4 d, for Biladyl, green extender and fresh-phos extenders without and with egg yolk, respectively). Motility parameters were best preserved in egg yolk supplemented Biladyl extender with a mean percentage of 86.3+/-10.5 motile spermatozoa after 7 d at 4 degrees C. Efficacy of egg yolk-supplemented commercial extenders on sperm motility at 4 degrees C was (in decreasing order) as follows: Biladyl > green extender > fresh-phos. However, high quality motility and the percentage of motile spermatozoa were highest with some of the laboratory prepared extenders: a 50% conservation rate of motile spermatozoa was observed following the use of supplemented egg yolk extenders. These are classified in decreasing order as follows: Tris-glucose (13+/-1 d) > Tris-fructose (9.7+/-0.6) > EDTA (4.+/-0.6 d) > Tris-bes (3.6+/-1.1 d). A low concentration of motile spermatozoa was still observed in the Tris-glucose egg yolk extender 16 d after collection, clearly demonstrating the importance of the medium and the beneficial effect of egg yolk on sperm motility of 4 degrees C chilled semen. Similar effects of extender were observed for acrosome reactions. Egg yolk clearly had a protective effect reducing acrosome reactions significantly in all media tested as follows: the

Characterization of Laboratory Prepared Concrete Pastes Exposed to High Alkaline and High Sodium Salt Solutions

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

Langton, C. A.

The objective of this study was to identify potential chemical degradation mechanisms for the Saltstone Disposal Unit (SDU) concretes, which over the performance life of the structures may be exposed to highly alkaline sodium salt solutions containing sulfate, hydroxide, and other potentially corrosive chemicals in salt solution and saltstone flush water, drain water, leachate and / or pore solution. The samples analyzed in this study were cement pastes prepared in the SIMCO Technologies, Inc. concrete laboratory. They were based on the paste fractions of the concretes used to construct the Saltstone Disposal Units (SDUs). SDU 1 and 4 concrete pastesmore » were represented by the PV1 test specimens. The paste in the SDU 2, 3, 5, and 6 concrete was represented by the PV2 test specimens. SIMCO Technologies, Inc. selected the chemicals and proportions in the aggressive solutions to approximate proportions in the saltstone pore solution [2, 3, 5, and 6]. These test specimens were cured for 56 days in curing chamber before being immersed in aggressive solutions. After exposure, the samples were frozen to prevent additional chemical transport and reaction. Selected archived (retrieved from the freezer) samples were sent to the Savannah River National Laboratory (SRNL) for additional characterization using x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray (EDX) spectroscopy. Characterization results are summarized in this report. In addition, a correlation between the oxide composition of the pastes and their chemical durability in the alkaline salt solutions is provided.« less

A Microfluidic Device for Preparing Next Generation DNA Sequencing Libraries and for Automating Other Laboratory Protocols That Require One or More Column Chromatography Steps

PubMed Central

Tan, Swee Jin; Phan, Huan; Gerry, Benjamin Michael; Kuhn, Alexandre; Hong, Lewis Zuocheng; Min Ong, Yao; Poon, Polly Suk Yean; Unger, Marc Alexander; Jones, Robert C.; Quake, Stephen R.; Burkholder, William F.

2013-01-01

Library preparation for next-generation DNA sequencing (NGS) remains a key bottleneck in the sequencing process which can be relieved through improved automation and miniaturization. We describe a microfluidic device for automating laboratory protocols that require one or more column chromatography steps and demonstrate its utility for preparing Next Generation sequencing libraries for the Illumina and Ion Torrent platforms. Sixteen different libraries can be generated simultaneously with significantly reduced reagent cost and hands-on time compared to manual library preparation. Using an appropriate column matrix and buffers, size selection can be performed on-chip following end-repair, dA tailing, and linker ligation, so that the libraries eluted from the chip are ready for sequencing. The core architecture of the device ensures uniform, reproducible column packing without user supervision and accommodates multiple routine protocol steps in any sequence, such as reagent mixing and incubation; column packing, loading, washing, elution, and regeneration; capture of eluted material for use as a substrate in a later step of the protocol; and removal of one column matrix so that two or more column matrices with different functional properties can be used in the same protocol. The microfluidic device is mounted on a plastic carrier so that reagents and products can be aliquoted and recovered using standard pipettors and liquid handling robots. The carrier-mounted device is operated using a benchtop controller that seals and operates the device with programmable temperature control, eliminating any requirement for the user to manually attach tubing or connectors. In addition to NGS library preparation, the device and controller are suitable for automating other time-consuming and error-prone laboratory protocols requiring column chromatography steps, such as chromatin immunoprecipitation. PMID:23894273

Thermoluminescence dating of a mikveh in Ichenhausen, Germany.

PubMed

Veronese, I; Göksu, H Y; Schwenk, P; Herzig, F

2008-04-01

A vaulted basement found at the rabbi's residential house which was oriented according to the requirements of a mikveh has created a controversy in the architectural history of the Ichenhausen Synagogue (Germany). The rabbi's residential house is known to have been built in 1781 during the replacement of the old Synagogue that had existed since 1687. However, the architectural documents concerning the residential house did not contain any information about either the presence or the construction of the mikveh in the basement. Three bricks collected from the northern, eastern and southern walls of the vaulted basement of the rabbi's residence were dated using the thermoluminescence method to find out if the mikveh belongs to the old Synagogue or was built during the construction of the residence. The archaeological dose was assessed using multi-aliquot regenerative and additive dose techniques using quartz extracted from bricks. The age calculations were based on the assessment of annual dose rate in quartz by taking into account the possible variations of water content in bricks. The TL dates of the bricks were found to vary between 1797+/-11 and 1772+/-16 for dry and water saturated environments, respectively. The TL results ruled out the possibility that the walls of the mikveh belong to the former Synagogue.

Mars Science Laboratory Rover Closeout

NASA Image and Video Library

2011-11-10

The Mars Science Laboratory mission rover, Curiosity, is prepared for final integration into the complete NASA spacecraft in this photograph taken inside the Payload Hazardous Servicing Facility at NASA Kennedy Space Center, Fla.

Roles of laboratories and laboratory systems in effective tuberculosis programmes

PubMed Central

van Deun, Armand; Kam, Kai Man; Narayanan, PR; Aziz, Mohamed Abdul

2007-01-01

Abstract Laboratories and laboratory networks are a fundamental component of tuberculosis (TB) control, providing testing for diagnosis, surveillance and treatment monitoring at every level of the health-care system. New initiatives and resources to strengthen laboratory capacity and implement rapid and new diagnostic tests for TB will require recognition that laboratories are systems that require quality standards, appropriate human resources, and attention to safety in addition to supplies and equipment. To prepare the laboratory networks for new diagnostics and expanded capacity, we need to focus efforts on strengthening quality management systems (QMS) through additional resources for external quality assessment programmes for microscopy, culture, drug susceptibility testing (DST) and molecular diagnostics. QMS should also promote development of accreditation programmes to ensure adherence to standards to improve both the quality and credibility of the laboratory system within TB programmes. Corresponding attention must be given to addressing human resources at every level of the laboratory, with special consideration being given to new programmes for laboratory management and leadership skills. Strengthening laboratory networks will also involve setting up partnerships between TB programmes and those seeking to control other diseases in order to pool resources and to promote advocacy for quality standards, to develop strategies to integrate laboratories’ functions and to extend control programme activities to the private sector. Improving the laboratory system will assure that increased resources, in the form of supplies, equipment and facilities, will be invested in networks that are capable of providing effective testing to meet the goals of the Global Plan to Stop TB. PMID:17639219

Mars Science Laboratory Cruise Stage

NASA Image and Video Library

2011-11-10

The cruise stage of NASA Mars Science Laboratory spacecraft is being prepared for final stacking of the spacecraft in this photograph from inside the Payload Hazardous Servicing Facility at NASA Kennedy Space Center, Fla.

Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

ERIC Educational Resources Information Center

Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

2015-01-01

Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the…

Report on Department of Homeland Security Sponsored Research Project at Lawrence Livermore National Laboratory on Preparation for an Improvised Nuclear Device Event

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

A., B

2008-07-31

Following the events of September 11th, a litany of imaginable horribles was trotted out before an anxious and concerned public. To date, government agencies and academics are still grappling with how to best respond to such catastrophes, and as Senator Lieberman's quote says above, now is the time to plan and prepare for such events. One of the nation's worst fears is that terrorists might detonate an improvised nuclear device (IND) in an American city. With 9/11 serving as the catalyst, the government and many NGOs have invested money into research and development of response capabilities throughout the country. Yet,more » there is still much to learn about how to best respond to an IND event. My summer 2008 internship at Lawrence Livermore National Laboratory afforded me the opportunity to look in depth at the preparedness process and the research that has been conducted on this issue. While at the laboratory I was tasked to collect, combine, and process research on how cities and the federal government can best prepare for the horrific prospect of an IND event. Specific projects that I was involved with were meeting reports, research reviews, and a full project report. Working directly with Brooke Buddemeier and his support team at the National Atmospheric Release Advisory Center, I was able to witness first hand, preparation for meetings with response planners to inform them of the challenges that an IND event would pose to the affected communities. In addition, I supported the Homeland Security Institute team (HSI), which was looking at IND preparation and preparing a Congressional report. I participated in meetings at which local responders expressed their concerns and contributed valuable information to the response plan. I specialized in the psycho-social aspects of an IND event and served as a technical advisor to some of the research groups. Alongside attending and supporting these meetings, I worked on an independent research project which collected

STAR: Preparing future science and math teachers through authentic research experiences at national laboratories

NASA Astrophysics Data System (ADS)

Keller, John; Rebar, Bryan

2012-11-01

The STEM Teacher and Researcher (STAR) Program provides 9-week paid summer research experiences at national research laboratories for future science and math teachers. The program, run by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the entire California State University (CSU) System, has arranged 290 research internships for 230 STEM undergraduates and credential candidates from 43 campuses over the past 6 years. The program has partnered with seven Department of Energy labs, four NASA centers, three NOAA facilities, and the National Optical Astronomy Observatory (NOAO). Primary components of the summer experience include a) conducting research with a mentor or mentor team, b) participating in weekly 2-3 hour workshops focused on translating lessons learned from summer research into classroom practice, and c) presenting a research poster or oral presentation and providing a lesson plan linked to the summer research experience. The central premise behind the STAR Program is that future science and math teachers can more effectively prepare the next generation of science, math, and engineering students if they themselves have authentic experiences as researchers.

Individual Events as a Laboratory for Argument: Analogues for Limited Preparation Events.

ERIC Educational Resources Information Center

Kay, Jack

To better serve as a laboratory for argument, individual events competition should represent analogues of "real world" argumentation/communication situations. The individual events laboratory must fulfill a pedagogical function, and should also "create" knowledge about argumentation strategies, specific fields of argument, and…

Development and Use of Online Prelaboratory Activities in Organic Chemistry to Improve Students' Laboratory Experience

ERIC Educational Resources Information Center

Chaytor, Jennifer L.; Al Mughalaq, Mohammad; Butler, Hailee

2017-01-01

Online prelaboratory videos and quizzes were prepared for all experiments in CHEM 231, Organic Chemistry I Laboratory. It was anticipated that watching the videos would help students be better prepared for the laboratory, decrease their anxiety surrounding the laboratory, and increase their understanding of the theories and concepts presented.…

Induced thermoluminescence as a method for dating recent volcanism: Eastern Snake River Plain, Idaho, USA

NASA Astrophysics Data System (ADS)

Sears, Derek W. G.; Sears, Hazel; Sehlke, Alexander; Hughes, Scott S.

2017-02-01

The induced thermoluminescence properties of 24 samples of basalts from volcanoes in the eastern Snake River Plain, Idaho, were measured as part of an investigation into the possibility of using this technique for dating purposes. The volcanic flows sampled ranged in age from 2200 years to 400,000 years. The thermoluminescence (TL) sensitivity values obtained, i.e., maximum induced TL normalized to that of the Dhajala meteorite (where Dhajala = 1000), ranged from 1.6 ± 0.3 to 226 ± 15 and showed a correlation between log TL and age with an r2 value of 0.47. Thus, TL sensitivity values correlate with age in the manner expected, although there is a high level of scatter. We discuss various mechanisms for the correlation and scatter, particularly (1) the role of primary (igneous processes) and secondary (solid state processes), (2) composition of the plagioclase feldspar, and (3) weathering. The induced TL signal from feldspars, the mineral responsible for the TL, is strongly dependent on their composition, and correcting for this improved the correlation (r2 = 0.7). Variations in primary feldspar are affecting the data, but we find no evidence that weathering of the samples is important. Further work is required to explore the remaining causes for the scatter and the TL-age trend. However, it is clear from the present study that induced TL has the potential for dating volcanism on the 2200 to 400,000 year time frame. This dating method, if successful, would be well-suited to spacecraft use since it requires low mass and low power instruments with a low data demand.

Transmission, reflection and thermoluminescence studies on GaS{sub 0.75}Se{sub 0.25} layered single crystals

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

Delice, S., E-mail: sdelice@metu.edu.tr; Isik, M.; Gasanly, N.M.

2015-10-15

Highlights: • Optical and thermoluminescence properties of Ga{sub 4}S{sub 3}Se crystals were investigated. • Indirect and direct band gap energies were found as 2.39 and 2.53 eV, respectively. • The activation energy of the trap center was determined as 495 meV. - Abstract: Optical and thermoluminescence properties on GaS{sub 0.75}Se{sub 0.25} crystals were investigated in the present work. Transmission and reflection measurements were performed at room temperature in the wavelength range of 400–1000 nm. Analysis revealed the presence of indirect and direct transitions with band gap energies of 2.39 and 2.53 eV, respectively. TL spectra obtained at low temperatures (10–300more » K) exhibited one peak having maximum temperature of 168 K. Observed peak was analyzed using curve fitting, initial rise and peak shape methods to calculate the activation energy of the associated trap center. All applied methods were consistent with the value of 495 meV. Attempt-to-escape-frequency and capture cross section of the trap center were determined using the results of curve fitting. Heating rate dependence studies of the glow curve in the range of 0.4–0.8 K/s resulted with decrease of TL intensity and shift of the peak maximum temperature to higher values.« less

Photoluminescence, thermoluminescence glow curve and emission characteristics of Y2O3:Er3 + nanophosphor

NASA Astrophysics Data System (ADS)

N. J., Shivaramu; B. N., Lakshminarasappa; K. R., Nagabhushana; H. C., Swart; Fouran, Singh

2018-01-01

Nanocrystalline Er3 + doped Y2O3crystals were prepared by a sol gel technique. X-ray diffraction (XRD) patterns showed the cubic structure of Y2O3 and the crystallite size was found to be 25 nm. Optical absorption showed absorption peaks at 454, 495 and 521 nm. These peaks are attributed to the 4F3/2 + 4F5/2, 4F7/2 and 2H11/2 + 4S3/2 transitions of Er3 +. Under excitation at 378 nm, the appearance of strong green (520-565 nm) down conversion emission assigned to the (2H11/2,4S3/2) → 4I15/2 transition and the feeble red (650-665 nm) emission is assigned to the 4F9/2 → 4I15/2 transition. The color chromaticity coordinates showed emission in the green region. The strong green emission of Y2O3:Er3 + nanophosphor may be useful for applications in solid compact laser devices. Thermoluminescence (TL) studies of γ-irradiated Y2O3:Er3 + showed a prominent TL glow peak maximum at 383 K along with a less intense shoulder peak at 425 K and a weak glow at 598 K. TL emission peaks with maxima at 545, 490, 588 and 622 nm for the doped sample were observed at a temperature of 383 K and these emissions were due to defect related to the host material. TL kinetic parameters were calculated by a glow curve deconvolution (GCD) method and the obtained results are discussed in detail for their possible usage in high dose dosimetry.

Supplement analysis for continued operation of Lawrence Livermore National Laboratory and Sandia National Laboratories, Livermore. Volume 2: Comment response document

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

NONE

1999-03-01

The US Department of Energy (DOE), prepared a draft Supplement Analysis (SA) for Continued Operation of Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories, Livermore (SNL-L), in accordance with DOE`s requirements for implementation of the National Environmental Policy Act of 1969 (NEPA) (10 Code of Federal Regulations [CFR] Part 1021.314). It considers whether the Final Environmental Impact Statement and Environmental Impact Report for Continued Operation of Lawrence Livermore National Laboratory and Sandia National Laboratories, Livermore (1992 EIS/EIR) should be supplement3ed, whether a new environmental impact statement (EIS) should be prepared, or no further NEPA documentation is required. The SAmore » examines the current project and program plans and proposals for LLNL and SNL-L, operations to identify new or modified projects or operations or new information for the period from 1998 to 2002 that was not considered in the 1992 EIS/EIR. When such changes, modifications, and information are identified, they are examined to determine whether they could be considered substantial or significant in reference to the 1992 proposed action and the 1993 Record of Decision (ROD). DOE released the draft SA to the public to obtain stakeholder comments and to consider those comments in the preparation of the final SA. DOE distributed copies of the draft SA to those who were known to have an interest in LLNL or SNL-L activities in addition to those who requested a copy. In response to comments received, DOE prepared this Comment Response Document.« less

Trap characterization by photo-transferred thermoluminescence in MgO nanoparticles

NASA Astrophysics Data System (ADS)

Isik, M.; Gasanly, N. M.

2018-05-01

Shallow trapping centers in MgO nanoparticles were characterized using photo-transferred thermoluminescence (TL) measurements. Experiments were carried out in low temperature range of 10-280 K with constant heating rate. Shallow traps were filled with charge carriers firstly by irradiating the sample at room temperature using S90/Y90 source and then illuminating at 10 K using blue LED. TL glow curve exhibited one peak around 150 K. Curve fitting analyses showed that this peak is composed of two individual peaks with maximum temperatures of 149.0 and 155.3 K. The activation energies of corresponding trapping centers were revealed as 0.70 and 0.91 eV. The dominant mechanism for TL process was found as second order kinetics which represent that fast retrapping is effective transitions taking place within the band gap. Structural characterization of MgO nanoparticles were investigated using x-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy measurements. Analyses of experimental observations indicated that MgO nanoparticles show good crystallinity with particle size in nanometer scale.

Two-dimensional dosimetry of radiotherapeutical proton beams using thermoluminescence foils.

PubMed

Czopyk, L; Klosowski, M; Olko, P; Swakon, J; Waligorski, M P R; Kajdrowicz, T; Cuttone, G; Cirrone, G A P; Di Rosa, F

2007-01-01

In modern radiation therapy such as intensity modulated radiation therapy or proton therapy, one is able to cover the target volume with improved dose conformation and to spare surrounding tissue with help of modern measurement techniques. Novel thermoluminescence dosimetry (TLD) foils, developed from the hot-pressed mixture of LiF:Mg,Cu,P (MCP TL) powder and ethylene-tetrafluoroethylene (ETFE) copolymer, have been applied for 2-D dosimetry of radiotherapeutical proton beams at INFN Catania and IFJ Krakow. A TLD reader with 70 mm heating plate and CCD camera was used to read the 2-D emission pattern of irradiated foils. The absorbed dose profiles were evaluated, taking into account correction factors specific for TLD such as dose and energy response. TLD foils were applied for measuring of dose distributions within an eye phantom and compared with predictions obtained from the MCNPX code and Eclipse Ocular Proton Planning (Varian Medical Systems) clinical radiotherapy planning system. We demonstrate the possibility of measuring 2-D dose distributions with point resolution of about 0.5 x 0.5 mm(2).

Identification of irradiated spices by the use of thermoluminescence method (TL)

NASA Astrophysics Data System (ADS)

Sharifzadeh, M.; Sohrabpour, M.

1993-07-01

In this paper the results of the investigations of identification of irradiated spices by the use of thermoluminescence method is reported. The materials used were black and red peppers, turmeric, cinnamon, and garlic powder. Gamma Cell 220 was used for irradiating samples at dose values of 2.5, 5, 7.5 and 10 kGy respectively. The TL intensity of the unirradiated spices as well as the fading characteristics of the irradiated samples having received a dose of 10 kGy have been measured. Post-irradiation temperature treatment of the irradiated (10 kGy) and unirradiated samples at 60°C and 100°C for 24 hours have been also performed. The results show that the TL intensities of unirradiated and irradiated samples from different batches of each spice are fairly distributed. A reasonable TL intensity versus dose has been observed in nearly all cases. Based on the observations made it is possible to distinguish irradiated spices after (4-9) months post-irradiation.

USGS Scientific Visualization Laboratory

USGS Publications Warehouse

,

1995-01-01

The U.S. Geological Survey's (USGS) Scientific Visualization Laboratory at the National Center in Reston, Va., provides a central facility where USGS employees can use state-of-the-art equipment for projects ranging from presentation graphics preparation to complex visual representations of scientific data. Equipment including color printers, black-and-white and color scanners, film recorders, video equipment, and DOS, Apple Macintosh, and UNIX platforms with software are available for both technical and nontechnical users. The laboratory staff provides assistance and demonstrations in the use of the hardware and software products.

Quantifying inter-laboratory variability in stable isotope analysis of ancient skeletal remains.

PubMed

Pestle, William J; Crowley, Brooke E; Weirauch, Matthew T

2014-01-01

Over the past forty years, stable isotope analysis of bone (and tooth) collagen and hydroxyapatite has become a mainstay of archaeological and paleoanthropological reconstructions of paleodiet and paleoenvironment. Despite this method's frequent use across anthropological subdisciplines (and beyond), the present work represents the first attempt at gauging the effects of inter-laboratory variability engendered by differences in a) sample preparation, and b) analysis (instrumentation, working standards, and data calibration). Replicate analyses of a 14C-dated ancient human bone by twenty-one archaeological and paleoecological stable isotope laboratories revealed significant inter-laboratory isotopic variation for both collagen and carbonate. For bone collagen, we found a sizeable range of 1.8‰ for δ13Ccol and 1.9‰ for δ15Ncol among laboratories, but an interpretatively insignificant average pairwise difference of 0.2‰ and 0.4‰ for δ13Ccol and δ15Ncol respectively. For bone hydroxyapatite the observed range increased to a troublingly large 3.5‰ for δ13Cap and 6.7‰ for δ18Oap, with average pairwise differences of 0.6‰ for δ13Cap and a disquieting 2.0‰ for δ18Oap. In order to assess the effects of preparation versus analysis on isotopic variability among laboratories, a subset of the samples prepared by the participating laboratories were analyzed a second time on the same instrument. Based on this duplicate analysis, it was determined that roughly half of the isotopic variability among laboratories could be attributed to differences in sample preparation, with the other half resulting from differences in analysis (instrumentation, working standards, and data calibration). These findings have serious implications for choices made in the preparation and extraction of target biomolecules, the comparison of results obtained from different laboratories, and the interpretation of small differences in bone collagen and hydroxyapatite isotope values

Quantifying Inter-Laboratory Variability in Stable Isotope Analysis of Ancient Skeletal Remains

PubMed Central

Pestle, William J.; Crowley, Brooke E.; Weirauch, Matthew T.

2014-01-01

Over the past forty years, stable isotope analysis of bone (and tooth) collagen and hydroxyapatite has become a mainstay of archaeological and paleoanthropological reconstructions of paleodiet and paleoenvironment. Despite this method's frequent use across anthropological subdisciplines (and beyond), the present work represents the first attempt at gauging the effects of inter-laboratory variability engendered by differences in a) sample preparation, and b) analysis (instrumentation, working standards, and data calibration). Replicate analyses of a 14C-dated ancient human bone by twenty-one archaeological and paleoecological stable isotope laboratories revealed significant inter-laboratory isotopic variation for both collagen and carbonate. For bone collagen, we found a sizeable range of 1.8‰ for δ13Ccol and 1.9‰ for δ15Ncol among laboratories, but an interpretatively insignificant average pairwise difference of 0.2‰ and 0.4‰ for δ13Ccol and δ15Ncol respectively. For bone hydroxyapatite the observed range increased to a troublingly large 3.5‰ for δ13Cap and 6.7‰ for δ18Oap, with average pairwise differences of 0.6‰ for δ13Cap and a disquieting 2.0‰ for δ18Oap. In order to assess the effects of preparation versus analysis on isotopic variability among laboratories, a subset of the samples prepared by the participating laboratories were analyzed a second time on the same instrument. Based on this duplicate analysis, it was determined that roughly half of the isotopic variability among laboratories could be attributed to differences in sample preparation, with the other half resulting from differences in analysis (instrumentation, working standards, and data calibration). These findings have serious implications for choices made in the preparation and extraction of target biomolecules, the comparison of results obtained from different laboratories, and the interpretation of small differences in bone collagen and hydroxyapatite isotope values

Evaluation of Exposure From a Low Energy X-Ray Device Using Thermoluminescent Dosimeters

NASA Technical Reports Server (NTRS)

Edwards, David L.; Harris, William S., Jr.

1997-01-01

The exposure from an electron beam welding device was evaluated using thermoluminescent dosimeters (TLDs). The device generated low energy X-rays which the current dose equivalent conversion algorithm was not designed to evaluate making it necessary to obtain additional information relating to TLD operation at the photon energies encountered with the device. This was accomplished by performing irradiations at the National Institute of Standards and Technology (NIST) using low energy X-ray techniques. The resulting data was used to determine TLD badge response for low energy X-rays and to establish the relationship between TLD element response and the dose equivalent at specific depths in tissue for these photon energies. The new energy/dose equivalent calibration data was used to calculate the shallow and eye dose equivalent of badges exposed to the device.

ChemCam Mast Unit Being Prepared for Laser Firing

NASA Image and Video Library

2010-12-23

Researchers prepare for a test of the Chemistry and Camera ChemCam instrument that will fly on NASA Mars Science Laboratory mission; researchers are preparing the instrument mast unit for a laser firing test.

Biothreat agents and pathology laboratories.

PubMed

Nelson, Ann; Wilson, Michael L

2007-11-01

Pathologists and laboratory staff are likely to be among the first health care workers to be aware that a potential bioterrorism attack has occurred. To prepare for such an event, it is necessary to be familiar with 1) the characteristics of bioterrorism attacks versus natural disease outbreaks, 2) which pathogens are potential bioterrorism agents; 3) the types of lesions that each causes; 4) the microbiological characteristics of each agent; 5) the Laboratory Response Network and reporting requirements, and 6) what resources are available.

[ISO 15189 accreditation in clinical microbiology laboratory: general concepts and the status in our laboratory].

PubMed

Akyar, Işin

2009-10-01

One important trend in the laboratory profession and quality management is the global convergence of laboratory operations. The goal of an accredited medical laboratory is to continue "offering useful laboratory service for diagnosis and treatment of the patients and also aid to the health of the nation". An accredited clinical laboratory is managed by a quality control system, it is competent technically and the laboratory service meets the needs of all its patients and physicians by taking the responsibility of all the medical tests and therapies. For this purpose, ISO 15189 international standard has been prepared by 2003. ISO 15189 standard is originated from the arrangement of ISO 17025 and ISO 9001:2000 standards. Many countries such as England, Germany, France, Canada and Australia have preferred ISO 15189 as their own laboratory accreditation programme, meeting all the requirements of their medical laboratories. The accreditation performance of a clinical microbiology laboratory is mainly based on five essential points; preanalytical, analytical, postanalytical, quality control programmes (internal, external, interlaboratory) and audits (internal, external). In this review article, general concepts on ISO 15189 accreditation standards for the clinical microbiology laboratories have been summarized and the status of a private laboratory (Acibadem LabMed, Istanbul) in Turkey has been discussed.

Preparation of Octadecyltrichlorosilane Nanopatterns Using Particle Lithography: An Atomic Force Microscopy Laboratory

ERIC Educational Resources Information Center

Highland, Zachary L.; Saner, ChaMarra K.; Garno, Jayne C.

2018-01-01

Experiments are described that involve undergraduates learning concepts of nanoscience and chemistry. Students prepare nanopatterns of organosilane films using protocols of particle lithography. A few basic techniques are needed to prepare samples, such as centrifuging, mixing, heating, and drying. Students obtain hands-on skills with nanoscale…

Habits of Mind for the Science Laboratory: Establishing Proper Safety Habits in the Laboratory Will Help Minimize the Risk of Accidents

ERIC Educational Resources Information Center

Hayes, Lisa; Smith, Margaret; Eick, Charles

2005-01-01

Lab safety begins with the teacher. Teachers must make learning how to be safe an integral and important part of their professional development and work. Teachers who are unfamiliar with laboratory instruction should take whatever steps necessary to prepare for the unique challenges associated with safety in conducting laboratory investigations…

Environmental Engineering Unit Operations and Unit Processes Laboratory Manual.

ERIC Educational Resources Information Center

O'Connor, John T., Ed.

This manual was prepared for the purpose of stimulating the development of effective unit operations and unit processes laboratory courses in environmental engineering. Laboratory activities emphasizing physical operations, biological, and chemical processes are designed for various educational and equipment levels. An introductory section reviews…

Application of flipped classroom pedagogy to the human gross anatomy laboratory: Student preferences and learning outcomes.

PubMed

Fleagle, Timothy R; Borcherding, Nicholas C; Harris, Jennie; Hoffmann, Darren S

2017-12-28

To improve student preparedness for anatomy laboratory dissection, the dental gross anatomy laboratory was transformed using flipped classroom pedagogy. Instead of spending class time explaining the procedures and anatomical structures for each laboratory, students were provided online materials to prepare for laboratory on their own. Eliminating in-class preparation provided the opportunity to end each period with integrative group activities that connected laboratory and lecture material and explored clinical correlations. Materials provided for prelaboratory preparation included: custom-made, three-dimensional (3D) anatomy videos, abbreviated dissection instructions, key atlas figures, and dissection videos. Data from three years of the course (n = 241 students) allowed for analysis of students' preferences for these materials and detailed tracking of usage of 3D anatomy videos. Students reported spending an average of 27:22 (±17:56) minutes preparing for laboratory, similar to the 30 minutes previously allocated for in-class dissection preparation. The 3D anatomy videos and key atlas figures were rated the most helpful resources. Scores on laboratory examinations were compared for the three years before the curriculum change (2011-2013; n = 242) and three years after (2014-2016; n = 241). There was no change in average grades on the first and second laboratory examinations. However, on the final semi-cumulative laboratory examination, scores were significantly higher in the post-flip classes (P = 0.04). These results demonstrate an effective model for applying flipped classroom pedagogy to the gross anatomy laboratory and illustrate a meaningful role for 3D anatomy visualizations in a dissection-based course. Anat Sci Educ. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

Solving the AI Planning Plus Scheduling Problem Using Model Checking via Automatic Translation from the Abstract Plan Preparation Language (APPL) to the Symbolic Analysis Laboratory (SAL)

NASA Technical Reports Server (NTRS)

Butler, Ricky W.; Munoz, Cesar A.; Siminiceanu, Radu I.

2007-01-01

This paper describes a translator from a new planning language named the Abstract Plan Preparation Language (APPL) to the Symbolic Analysis Laboratory (SAL) model checker. This translator has been developed in support of the Spacecraft Autonomy for Vehicles and Habitats (SAVH) project sponsored by the Exploration Technology Development Program, which is seeking to mature autonomy technology for the vehicles and operations centers of Project Constellation.

Computerized glow curve deconvolution of thermoluminescent emission from polyminerals of Jamaica Mexican flower

NASA Astrophysics Data System (ADS)

Favalli, A.; Furetta, C.; Zaragoza, E. Cruz; Reyes, A.

The aim of this work is to study the main thermoluminescence (TL) characteristics of the inorganic polyminerals extracted from dehydrated Jamaica flower or roselle (Hibiscus sabdariffa L.) belonging to Malvaceae family of Mexican origin. TL emission properties of the polymineral fraction in powder were studied using the initial rise (IR) method. The complex structure and kinetic parameters of the glow curves have been analysed accurately using the computerized glow curve deconvolution (CGCD) assuming an exponential distribution of trapping levels. The extension of the IR method to the case of a continuous and exponential distribution of traps is reported, such as the derivation of the TL glow curve deconvolution functions for continuous trap distribution. CGCD is performed both in the case of frequency factor, s, temperature independent, and in the case with the s function of temperature.

Thermoluminescence analysis can identify irradiated ingredient in soy sauce before and after pasteurization

NASA Astrophysics Data System (ADS)

Lee, Jeong-Eun; Sanyal, Bhaskar; Akram, Kashif; Jo, Yunhee; Baek, Ji-Yeong; Kwon, Joong-Ho

2017-05-01

Thermoluminescence (TL) analysis was conducted to identify small quantities (0.5%, 1%, and 1.5%) of γ ray-or electron beam-irradiated garlic powder in a soy sauce after commercial pasteurization. The sauce samples with γ ray- and electron beam-irradiated (0, 1 or 10 kGy) garlic powder showed detectable TL glow curves, characterized by radiation-induced maximum in the temperature range of 180-225 °C. The successful identification of soy sauces with an irradiation history was dependent on both the mixing ratio of the irradiated ingredient and the irradiation dose. Post-irradiation pasteurization (85 °C, 30 min) caused no considerable changes in TL glow shape or intensity. Interlaboratory tests demonstrated that the shape and intensity of the first TL glow curve (TL1) could be a better detection marker than a TL ratio (TL1/TL2).

National and international veterinary reference laboratories for infectious diseases.

PubMed

Edwards, S; Alexander, D

1998-08-01

Reference laboratories play an increasingly important role in the harmonisation of laboratory diagnostic tests and the standardisation of veterinary vaccines. This is particularly important in building confidence between international trading partners. The authors review aspects of the organisation, designation and support of reference laboratories for infectious diseases of animals and discuss the principal activities which such laboratories would normally perform. These activities include advice and consultancy, publications and communication, training, research, disease surveillance, maintenance of culture collections, evaluation of reference methods, preparation of reference materials and organisation of inter-laboratory comparisons.

Photoluminescence, thermoluminescence glow curve and emission characteristics of Y2O3:Er3+ nanophosphor.

PubMed

N J, Shivaramu; B N, Lakshminarasappa; K R, Nagabhushana; H C, Swart; Fouran, Singh

2018-01-15

Nanocrystalline Er 3+ doped Y 2 O 3 crystals were prepared by a sol gel technique. X-ray diffraction (XRD) patterns showed the cubic structure of Y 2 O 3 and the crystallite size was found to be ~25nm. Optical absorption showed absorption peaks at 454, 495 and 521nm. These peaks are attributed to the 4 F 3/2 + 4 F 5/2 , 4 F 7/2 and 2 H 11/2 + 4 S 3/2 transitions of Er 3+ . Under excitation at 378nm, the appearance of strong green (520-565nm) down conversion emission assigned to the ( 2 H 11/2, 4 S 3/2 )→ 4 I 15/2 transition and the feeble red (650-665nm) emission is assigned to the 4 F 9/2 → 4 I 15/2 transition. The color chromaticity coordinates showed emission in the green region. The strong green emission of Y 2 O 3 :Er 3+ nanophosphor may be useful for applications in solid compact laser devices. Thermoluminescence (TL) studies of γ-irradiated Y 2 O 3 :Er 3+ showed a prominent TL glow peak maximum at 383K along with a less intense shoulder peak at ~425K and a weak glow at 598K. TL emission peaks with maxima at 545, 490, 588 and 622nm for the doped sample were observed at a temperature of 383K and these emissions were due to defect related to the host material. TL kinetic parameters were calculated by a glow curve deconvolution (GCD) method and the obtained results are discussed in detail for their possible usage in high dose dosimetry. Copyright © 2017 Elsevier B.V. All rights reserved.

Diagnostic equipment outside the laboratory.

PubMed Central

Burrin, J M; Fyffe, J A

1988-01-01

A questionnaire was circulated to clinical biochemistry laboratories in the North West Thames region of the United Kingdom requesting information on extralaboratory equipment. Data on the types and numbers of instruments in use, their relationship with the laboratory, and quality assurance procedures were obtained. Laboratories were prepared to maintain equipment over which they had no responsibility for purchase, training of users, or use. The quality assurance of these instruments gave even greater cause for concern. Although internal quality control procedures were performed on many of the instruments, laboratories were involved in only a minority of these procedures. Quality control procedures and training of users were undertaken on site in less than 50% of blood gas analysers and bilirubin meters and in less than 25% of glucose meters. External quality assessment procedures were non-existent for all of the instruments in use with the exception of glucose stick meters in two laboratories. PMID:3192750

Cyclic joint remote state preparation in noisy environment

NASA Astrophysics Data System (ADS)

Zhang, Chang-yue; Bai, Ming-qiang; Zhou, Si-qi

2018-06-01

We propose a scheme of cyclic joint remote state preparation for three sides, which takes advantage of three GHZ states to compose product state as quantum channel. Suppose there are six legitimate participants, says Alice, Bob, Charlie, David, Emma and Fred in the scheme. It can be shown that Alice and David can remotely prepare a single-qubit state on Bob's side; meanwhile, Bob and Emma can remotely prepare a desired quantum state on Charlie's side, and Charlie and Fred can also remotely prepare a single-qubit state on Alice's side at the same time. Further, it can be achieved in the opposite direction of the cycle by changing the quantum channel. Based on it, we generalize this protocol to N (N≥3) sides utilizing three multi-qubit GHZ-type states as quantum channel. Therefore, the scheme can achieve cyclic joint remote state preparation, which remotely prepares N states in quantum network with N-party, simultaneously. In addition, we consider that the effect of amplitude-damping noise of the initial states is prepared in four different laboratory. Clearly, we use fidelity to describe how much information has been lost in the cyclic process. Our investigation about the effect of noise shows that the preparing of the initial state in different laboratories will affect the loss of information.

Basic Laboratory Skills. Training Module 5.300.2.77.

ERIC Educational Resources Information Center

Kirkwood Community Coll., Cedar Rapids, IA.

This document is an instructional module package prepared in objective form for use by an instructor familiar with the basic chemical and microbiological laboratory equipment and procedures used in water and wastewater treatment plant laboratories. Included are objectives, instructor guides, student handouts and transparency masters. This module…

Preparation for microgravity - The role of the Microgravity Material Science Laboratory

NASA Technical Reports Server (NTRS)

Johnston, J. Christopher; Rosenthal, Bruce N.; Meyer, Maryjo B.; Glasgow, Thomas K.

1988-01-01

Experiments at the NASA Lewis Research Center's Microgravity Material Science Laboratory using physical and mathematical models to delineate the effects of gravity on processes of scientific and commercial interest are discussed. Where possible, transparent model systems are used to visually track convection, settling, crystal growth, phase separation, agglomeration, vapor transport, diffusive flow, and polymer reactions. Materials studied include metals, alloys, salts, glasses, ceramics, and polymers. Specific technologies discussed include the General Purpose furnace used in the study of metals and crystal growth, the isothermal dendrite growth apparatus, the electromagnetic levitator/instrumented drop tube, the high temperature directional solidification furnace, the ceramics and polymer laboratories and the center's computing facilities.

Coleman prepares to insert samples into the MELFI

NASA Image and Video Library

2010-12-27

ISS026-E-023768 (27 Dec. 2010) --- NASA astronaut Catherine (Cady) Coleman, Expedition 26 flight engineer, prepares to insert samples into the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) study in the Japanese Kibo laboratory of the International Space Station.

Virtual Simulations as Preparation for Lab Exercises: Assessing Learning of Key Laboratory Skills in Microbiology and Improvement of Essential Non-Cognitive Skills.

PubMed

Makransky, Guido; Thisgaard, Malene Warming; Gadegaard, Helen

2016-01-01

To investigate if a virtual laboratory simulation (vLAB) could be used to replace a face to face tutorial (demonstration) to prepare students for a laboratory exercise in microbiology. A total of 189 students who were participating in an undergraduate biology course were randomly selected into a vLAB or demonstration condition. In the vLAB condition students could use a vLAB at home to 'practice' streaking out bacteria on agar plates in a virtual environment. In the demonstration condition students were given a live demonstration from a lab tutor showing them how to streak out bacteria on agar plates. All students were blindly assessed on their ability to perform the streaking technique in the physical lab, and were administered a pre and post-test to determine their knowledge of microbiology, intrinsic motivation to study microbiology, and self-efficacy in the field of microbiology prior to, and after the experiment. The results showed that there were no significant differences between the two groups on their lab scores, and both groups had similar increases in knowledge of microbiology, intrinsic motivation to study microbiology, as well as self-efficacy in the field of microbiology. Our data show that vLABs function just as well as face to face tutorials in preparing students for a physical lab activity in microbiology. The results imply that vLABs could be used instead of face to face tutorials, and a combination of virtual and physical lab exercises could be the future of science education.

To the Geoportal and Beyond! Preparing the Earth Observing Laboratory's Datasets for Inter-Repository Discovery

NASA Astrophysics Data System (ADS)

Gordon, S.; Dattore, E.; Williams, S.

2014-12-01

Even when a data center makes it's datasets accessible, they can still be hard to discover if the user is unaware of the laboratory or organization the data center supports. NCAR's Earth Observing Laboratory (EOL) is no exception. In response to this problem and as an inquiry into the feasibility of inter-connecting all of NCAR's repositories at a discovery layer, ESRI's Geoportal was researched. It was determined that an implementation of Geoportal would be a good choice to build a proof of concept model of inter-repository discovery around. This collaborative project between the University of Illinois and NCAR is coordinated through the Data Curation Education in Research Centers program. This program is funded by the Institute of Museum and Library Services.Geoportal is open source software. It serves as an aggregation point for metadata catalogs of earth science datasets, with a focus on geospatial information. EOL's metadata is in static THREDDS catalogs. Geoportal can only create records from a THREDDS Data Server. The first step was to make EOL metadata more accessible by utilizing the ISO 19115-2 standard. It was also decided to create DIF records so EOL datasets could be ingested in NASA's Global Change Master Directory (GCMD). To offer records for harvest, it was decided to develop an OAI-PMH server. To make a compliant server, the OAI_DC standard was also implemented. A server was written in Perl to serve a set of static records. We created a sample set of records in ISO 19115-2, FGDC, DIF, and OAI_DC. We utilized GCMD shared vocabularies to enhance discoverability and precision. The proof of concept was tested and verified by having another NCAR laboratory's Geoportal harvest our sample set. To prepare for production, templates for each standard were developed and mapped to the database. These templates will help the automated creation of records. Once the OAI-PMH server is re-written in a Grails framework a dynamic representation of EOL

Comparison of the microbial dynamics and biochemistry of laboratory sourdoughs prepared with grape, apple and yogurt.

PubMed

Gordún, Elena; del Valle, Luis J; Ginovart, Marta; Carbó, Rosa

2015-09-01

The microbiological culture-dependent characterization and physicochemical characteristics of laboratory sourdough prepared with grape (GS) were evaluated and compared with apple (AS) and yogurt (YS), which are the usual Spanish sourdough ingredients. Ripe GS took longer than AS and YS to reach the appropriate acidity and achieved lower values of lactic acid. In all sourdoughs, the lactic acid bacteria (LAB) increased during processing and were the dominant microorganisms (>1E+8 CFU/g). GS, as well as AS, had high diversity of LAB species. In ripe YS, Pediococcus pentosaceus was the only species identified; in GS and AS, several Lactobacilli were also found, Lb. plantarum, Lb. brevis, and Lb. sakei; in addition, in GS Weisella cibaria also appeared. Regarding the yeast population, non-Saccharomyces yeasts from GS and AS showed a very high specific population (>1E+7 CFU/g), but this was reduced in ripe sourdough (<1E+4 CFU/g). Finally, the Saccharomyces group dominated in all sourdoughs. Starting ingredients or raw material provided microbiological specificity to sourdoughs, and grape could be considered one of them. © The Author(s) 2014.

Prompt isothermal decay of thermoluminescence in an apatite exhibiting strong anomalous fading

NASA Astrophysics Data System (ADS)

Sfampa, I. K.; Polymeris, G. S.; Tsirliganis, N. C.; Pagonis, V.; Kitis, G.

2014-02-01

Anomalous fading (AF) is one of the most serious drawbacks in thermoluminescence (TL) and optically stimulated luminescence (OSL) dating. In the present work the isothermal decay of TL signals from Durango apatite is studied for temperatures located on the rising part of the main TL peak. This material is known to exhibit strong AF phenomena, and its isothermal TL decay properties have not been studied previously. The experimental results show that the characteristic decay time of the isothermal signal does not depend of the temperature, and that this signal does not exhibit the strong temperature dependence expected from conventional TL kinetic theories. This is further direct experimental evidence for the possible presence of tunneling phenomena in this material. The isothermal decay curves are analyzed and discussed within the framework of conventional theories of TL, as well as within the context of a recently developed tunneling kinetic model for random distributions of electron-hole pairs in luminescent materials.

Effect of thermal treatment on TL response of CaSO₄:Dy obtained using a new preparation method.

PubMed

González, P R; Cruz-Zaragoza, E; Furetta, C; Azorín, J; Alcántara, B C

2013-05-01

We report the effect of thermal treatment on thermoluminescent (TL) sensitivity property of CaSO4:Dy obtained by a new preparation method at Instituto Nacional de Investigaciones Nucleares (ININ) of Mexico. Samples of phosphor powder were subjected to different thermal treatments respectively at 773, 873, 973 and 1,173K for 1h and then irradiated from 0.1 to 1,000 Gy gamma doses. Low energy dependence was analyzed too by irradiating with X-rays in the range of 16-145 keV. The results were normalized to the energy (1,252 keV) of (60)Co and they were compared with those obtained using the commercial dosimeters TLD-100. Also the kinetic parameters were determined by deconvolution of glow curve. Copyright © 2013 Elsevier Ltd. All rights reserved.

Feasibility of reading LiF thermoluminescent dosimeters by electron spin resonance

NASA Astrophysics Data System (ADS)

Breen, S. L.; Battista, J. J.

1999-08-01

Lithium fluoride is a commonly used solid state dosimeter. During irradiation, electrons and holes become trapped in crystal imperfections; thermoluminescence dosimetry measures their thermally induced recombination. Electron paramagnetic resonance (EPR) spectroscopy can be used to measure the resonant absorption of microwaves by the unpaired electrons trapped in LiF. In an effort to extend the use of LiF dosimeters to smaller sizes and to the harsh environments encountered in internal dosimetry, EPR was evaluated as an alternative technique to read the radiation dose delivered to TLD-100 dosimeters. TLD-100 rods were irradiated with a 60Co source to doses of 10 Gy to 100 Gy. A radiation-induced signal (with a g-value of 2.002) could be detected only at liquid nitrogen temperatures at doses above 20 Gy. The EPR spectrum of irradiated LiF contains three components, one of which correlates positively with dose. However, the low sensitivity of the technique, and difficulty in interpreting the EPR spectrum from polycrystalline dosimeters, preclude its use as a dosimetry technique.

Feasibility of reading LiF thermoluminescent dosimeters by electron spin resonance.

PubMed

Breen, S L; Battista, J J

1999-08-01

Lithium fluoride is a commonly used solid state dosimeter. During irradiation, electrons and holes become trapped in crystal imperfections; thermoluminescence dosimetry measures their thermally induced recombination. Electron paramagnetic resonance (EPR) spectroscopy can be used to measure the resonant absorption of microwaves by the unpaired electrons trapped in LiF. In an effort to extend the use of LiF dosimeters to smaller sizes and to the harsh environments encountered in internal dosimetry, EPR was evaluated as an alternative technique to read the radiation dose delivered to TLD-100 dosimeters. TLD-100 rods were irradiated with a 60Co source to doses of 10 Gy to 100 Gy. A radiation-induced signal (with a g-value of 2.002) could be detected only at liquid nitrogen temperatures at doses above 20 Gy. The EPR spectrum of irradiated LiF contains three components, one of which correlates positively with dose. However, the low sensitivity of the technique, and difficulty in interpreting the EPR spectrum from polycrystalline dosimeters, preclude its use as a dosimetry technique.

[The application of non-annealing thermoluminescent dosimetry (TLD)].

PubMed

Wu, J M; Chen, C S; Lan, R H

1993-06-01

Conventional use of Thermoluminescence (TL) in radiation dosimetry is very time-consuming. It requires repeating the procedures of preheating and annealing. In an attempt to simplify these procedures, we conducted an experiment of non-annealing TL dosimetry. This article reports the experiment's results. We adopted Lithium Fluoride (LiF) chip (TLD-100) in polystyrene under the exposure of Co-60, and the result was taken by HAR-SHAW-4000 TL reading system. The TL response was analyzed, including linearity, reproducibility and fading test. Because non-annealing TL response was greatly influenced by residual electron, TLD calibration curves were separated into two parts: (1) high dose region (HDR, 50-1500 cGy); (2) low dose region (LDR, 0-50 cGy). When TL dosimeters were exposed to a single high does (about 500 cGy), the HDR could be reproduced within 3% and fit a good linearity. For LDR, we had to give up the tail of glow curve in the high temperature region. We could then get good linearity and reproducibility. Furthermore, fading of non-annealing was apparently larger than annealing. We could control the fading of non-annealing was apparently larger than annealing. We could control the fading influence within 1% by taking the TL reading one hour after exposure. On the other hand, a combination of photon and electron exposure was also performed by non-annealing TL dosimetry. The results were compatible with Co-60 exposure in the same system.

Facilitating Improvements in Laboratory Report Writing Skills with Less Grading: A Laboratory Report Peer-Review Process†

PubMed Central

Brigati, Jennifer R.; Swann, Jerilyn M.

2015-01-01

Incorporating peer-review steps in the laboratory report writing process provides benefits to students, but it also can create additional work for laboratory instructors. The laboratory report writing process described here allows the instructor to grade only one lab report for every two to four students, while giving the students the benefits of peer review and prompt feedback on their laboratory reports. Here we present the application of this process to a sophomore level genetics course and a freshman level cellular biology course, including information regarding class time spent on student preparation activities, instructor preparation, prerequisite student knowledge, suggested learning outcomes, procedure, materials, student instructions, faculty instructions, assessment tools, and sample data. T-tests comparing individual and group grading of the introductory cell biology lab reports yielded average scores that were not significantly different from each other (p = 0.13, n = 23 for individual grading, n = 6 for group grading). T-tests also demonstrated that average laboratory report grades of students using the peer-review process were not significantly different from those of students working alone (p = 0.98, n = 9 for individual grading, n = 6 for pair grading). While the grading process described here does not lead to statistically significant gains (or reductions) in student learning, it allows student learning to be maintained while decreasing instructor workload. This reduction in workload could allow the instructor time to pursue other high-impact practices that have been shown to increase student learning. Finally, we suggest possible modifications to the procedure for application in a variety of settings. PMID:25949758

Facilitating improvements in laboratory report writing skills with less grading: a laboratory report peer-review process.

PubMed

Brigati, Jennifer R; Swann, Jerilyn M

2015-05-01

Incorporating peer-review steps in the laboratory report writing process provides benefits to students, but it also can create additional work for laboratory instructors. The laboratory report writing process described here allows the instructor to grade only one lab report for every two to four students, while giving the students the benefits of peer review and prompt feedback on their laboratory reports. Here we present the application of this process to a sophomore level genetics course and a freshman level cellular biology course, including information regarding class time spent on student preparation activities, instructor preparation, prerequisite student knowledge, suggested learning outcomes, procedure, materials, student instructions, faculty instructions, assessment tools, and sample data. T-tests comparing individual and group grading of the introductory cell biology lab reports yielded average scores that were not significantly different from each other (p = 0.13, n = 23 for individual grading, n = 6 for group grading). T-tests also demonstrated that average laboratory report grades of students using the peer-review process were not significantly different from those of students working alone (p = 0.98, n = 9 for individual grading, n = 6 for pair grading). While the grading process described here does not lead to statistically significant gains (or reductions) in student learning, it allows student learning to be maintained while decreasing instructor workload. This reduction in workload could allow the instructor time to pursue other high-impact practices that have been shown to increase student learning. Finally, we suggest possible modifications to the procedure for application in a variety of settings.

Long-term pavement performance project laboratory materials testing and handling guide

DOT National Transportation Integrated Search

2007-09-01

The Long Term Pavement Performance (LTPP) Laboratory Material Testing Guide was originally prepared for laboratory material handling and testing of material specimens and samples of asphalt materials, portland cement concrete, aggregates, and soils u...

An electron-beam dose deposition experiment: TIGER 1-D simulation code versus thermoluminescent dosimetry

NASA Astrophysics Data System (ADS)

Murrill, Steven R.; Tipton, Charles W.; Self, Charles T.

1991-03-01

The dose absorbed in an integrated circuit (IC) die exposed to a pulse of low-energy electrons is a strong function of both electron energy and surrounding packaging materials. This report describes an experiment designed to measure how well the Integrated TIGER Series one-dimensional (1-D) electron transport simulation program predicts dose correction factors for a state-of-the-art IC package and package/printed circuit board (PCB) combination. These derived factors are compared with data obtained experimentally using thermoluminescent dosimeters (TLD's) and the FX-45 flash x-ray machine (operated in electron-beam (e-beam) mode). The results of this experiment show that the TIGER 1-D simulation code can be used to accurately predict FX-45 e-beam dose deposition correction factors for reasonably complex IC packaging configurations.

Framework for leadership and training of Biosafety Level 4 laboratory workers.

PubMed

Le Duc, James W; Anderson, Kevin; Bloom, Marshall E; Estep, James E; Feldmann, Heinz; Geisbert, Joan B; Geisbert, Thomas W; Hensley, Lisa; Holbrook, Michael; Jahrling, Peter B; Ksiazek, Thomas G; Korch, George; Patterson, Jean; Skvorak, John P; Weingartl, Hana

2008-11-01

Construction of several new Biosafety Level 4 (BSL-4) laboratories and expansion of existing operations have created an increased international demand for well-trained staff and facility leaders. Directors of most North American BSL-4 laboratories met and agreed upon a framework for leadership and training of biocontainment research and operations staff. They agreed on essential preparation and training that includes theoretical consideration of biocontainment principles, practical hands-on training, and mentored on-the-job experiences relevant to positional responsibilities as essential preparation before a person's independent access to a BSL-4 facility. They also agreed that the BSL-4 laboratory director is the key person most responsible for ensuring that staff members are appropriately prepared for BSL-4 operations. Although standardized certification of training does not formally exist, the directors agreed that facility-specific, time-limited documentation to recognize specific skills and experiences of trained persons is needed.

UK dental laboratory technicians' views on the efficacy and teaching of clinical-laboratory communication.

PubMed

Juszczyk, A S; Clark, R K F; Radford, D R

2009-05-23

The General Dental Council states that 'good dental care is delivered by a team' and restorative treatment is enhanced by communication between team members. Commercial dental laboratories are ideally placed to comment on effective communication. To investigate contemporary attitudes and communication between dentist and dental technician from the technician's perspective. Eight hundred and three dental laboratories were invited to take part in a postal survey covering dentist/laboratory communication and the dentist's understanding of technical procedures. Forty percent of laboratories responded. Only 9% scored communication as very good, 48% scored communication with newly qualified dentists better than with established dentists but only 26% considered that dental students were taught to communicate with dental laboratories effectively. The free comments that the respondents were invited to make identified three distinct themes, 'recognition within the dental team', 'effective communication between dentist and dental technician' and 'dentists lack of technical knowledge'. Effective communication between dentist and dental technician is often poor. It was the view of the dental technicians who responded that newly qualified dentists do not have an appropriate understanding of technical techniques. Dental schools are still not preparing new graduates to communicate effectively with dental laboratories.

Mars Science Laboratory and Its Payload Fairing

NASA Image and Video Library

2011-11-10

Preparations are under way to enclose NASA Mars Science Laboratory in an Atlas V rocket payload fairing. The fairing protects the spacecraft from the impact of aerodynamic pressure and heating during ascent.

Air Force Weapons Laboratory Computational Requirements for 1976 Through 1980

DTIC Science & Technology

1976-01-01

Air Force Weapons Laboratory , Attn: DYS, Kirtland AFB, NM 87117...final report was prepared by the Air Force Weapons Laboratory , Kirtland Air Force Base, New Mexico under Job Order 06CB. Dr. Clifford E. Rhoades, Jr... Force Base, New Mexico 87117 62601F, 06CB II. CONTROLLING OFFICE NAME AND ADDRESS Ai"- Force Weapons Laboratory / Jan 1076 Kirtland Air Force Base,

Pacific Northwest Laboratory Institutional Plan FY 1995-2000

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

Not Available

1994-12-01

This report serves as a document to describe the role PNL is positioned to take in the Department of Energy`s plans for its national centers in the period 1995-2000. It highlights the strengths of the facilities and personnel present at the laboratory, touches on the accomplishments and projects they have contributed to, and the direction being taken to prepare for the demands to be placed on DOE facilities in the near and far term. It consists of sections titled: director`s statement; laboratory mission and core competencies; laboratory strategic plan; laboratory initiatives; core business areas; critical success factors.

Preparation of Lead Compounds: An Exercise in Applied Chemistry.

ERIC Educational Resources Information Center

Laing, Michael; And Others

1987-01-01

Describes an exercise developed at the University of Natal (South Africa) in which students visit a plant which manufactures a variety of lead compounds. Outlines the procedures for the laboratory preparation of lead compounds that students prepare with samples they collected at the plant. (TW)

Thermoluminescence response of flat optical fiber subjected to 9 MeV electron irradiations

NASA Astrophysics Data System (ADS)

Hashim, S.; Omar, S. S. Che; Ibrahim, S. A.; Hassan, W. M. S. Wan; Ung, N. M.; Mahdiraji, G. A.; Bradley, D. A.; Alzimami, K.

2015-01-01

We describe the efforts of finding a new thermoluminescent (TL) media using pure silica flat optical fiber (FF). The present study investigates the dose response, sensitivity, minimum detectable dose and glow curve of FF subjected to 9 MeV electron irradiations with various dose ranges from 0 Gy to 2.5 Gy. The above-mentioned TL properties of the FF are compared with commercially available TLD-100 rods. The TL measurements of the TL media exhibit a linear dose response over the delivered dose using a linear accelerator. We found that the sensitivity of TLD-100 is markedly 6 times greater than that of FF optical fiber. The minimum detectable dose was found to be 0.09 mGy for TLD-100 and 8.22 mGy for FF. Our work may contribute towards the development of a new dosimeter for personal monitoring purposes.

Natural Thermoluminescence and the Terrestrial and Orbital Histories of Ordinary Chondrites

NASA Astrophysics Data System (ADS)

Akridge, Jannette Marie Cunningham

The amount of stored thermoluminescence in a meteorite is a direct result of storage temperature and duration of radiation exposure. I have used these relationships to study the terrestrial and orbital histories of meteorites. The orbital history of a meteorite is investigated using the high temperature portion of the glow curve while the study of terrestrial histories requires the use of the low temperature region. The build-up and decay parameters for the high temperature region of the thermoluminescence glow-curve for Paragould, Lost City, Tilden, Chicora, Innisfree and Pribram have been determined. All of the samples reach saturation at 360 +/- 10 krad and have a RO value (the dose necessary to fill 63.2% of the total available traps) of 80 krad. There are four trap populations with average temperatures of 321 +/- 7.3°C, 367 +/- 5.8°C, 406 +/- 4.8°C, and 462 +/- 5.8°C and average E values of 1.27 +/- 0.02 eV, 1.38 +/- 0.04 eV, 1.45 +/- 0.01 eV, and 1.51 +/- 0.01 eV; and averages s values of 7.87 +/- 1.85 x 109 sec-1 , 9.89 +/- 7.30 x 109 sec-1, 5.95 +/- 1.66 x 109 sec-1, and 2.01 +/- 0.50 x 109 sec-1, respectively. Based on calculations using the above TL parameters, I argue that Pribram was exposed to a higher average dose rate in space than Lost City and Innisfree. It is also possible that Paragould and Tilden have perihelia similar to that of Pribram. If the albedo of the two meteorites is assumed to be similar to Pribram then the aphelion must have been less than 3.5 AU, but if their albedos were lower than Pribram's their aphelia could have been as much as 4.0 AU. Chicora probably had a perihelion similar to that of Lost City and Innisfree but its aphelion was probably less than that of Lost City. I have measured the natural TL in the ``drained zone'' of 15 meteorites. The data indicate that this technique could be used with greater accuracy than 36Cl to determine terrestrial ages of meteorites with ages <200 ka, after which TL equilibrium is reached

Ag nanoparticle effects on the thermoluminescent properties of monoclinic ZrO2 exposed to ultraviolet and gamma radiation

NASA Astrophysics Data System (ADS)

Villa-Sanchéz, G.; Mendoza-Anaya, D.; Gutiérrez-Wing, C.; Pérez-Hernández, R.; González-Martínez, P. R.; Ángeles-Chavez, C.

2007-07-01

The goal of this work was to analyse ZrO2 in the pure state and when doped with Ag nanoparticles, by electron microscopy, x-ray diffraction and thermoluminescence methods. According to the results obtained, Ag nanoparticles did not modify the morphology or the crystalline structure of the ZrO2. The thermoluminescent (TL) response of pure ZrO2 showed two peaks, one at 334 K and the other at 417 K, when it was exposed to ultraviolet (UV) radiation, and at 342 and 397 K when gamma radiation was used. For ZrO2 impregnated with Ag nanoparticles a diminished TL intensity due to nanoparticle shielding was observed, but the glow curve shape was similar. However, when Ag nanoparticles were added during the ZrO2 synthesis, a shift of the TL peaks towards higher temperature values with reference to pure ZrO2 was observed. A linear dependence of the integrated TL signal as a function of the irradiation dose was observed in all analysed samples. It was possible to determine some kinetic parameters, such as activation energy, kinetic order and frequency factor, using the sequential quadratic programming glow curve deconvolution; it was found that these values are highly dependent on the type of radiation used. Ag nanoparticles present in ZrO2 also modified the kinetic parameters, mainly when they were added during the synthesis of ZrO2. Our results reinforce the possibilities of using pure and doped ZrO2 as an appropriate dosimetric material in radiation physics.

Teachers' self-assessed levels of preparation

NASA Astrophysics Data System (ADS)

White, Susan C.

2016-02-01

Every four years we survey a nationally representative sample of high school physics teachers. We define anyone who teaches at least one physics class to be a "physics teacher." About 40% of these teachers teach a majority of their classes in subjects other than physics. We also ask teachers to rate how well prepared they felt in various aspects of teaching. The response choices are "not adequately prepared," "adequately prepared," and "very well prepared." The accompanying figure shows the proportion of teachers who reported feeling adequately or very well prepared in the following aspects of teaching: • Basic physics knowledge, • Other science knowledge, • Application of physics to everyday experience, • Use of demonstrations, • Instructional laboratory design, • Use of computers in physics instruction and labs, and • Recent developments in physics.

The Orbits of Meteorites from Natural Thermoluminescence. Attachment 5

NASA Technical Reports Server (NTRS)

Benoit, P. H.; Sears, D. W. G.

1997-01-01

The natural thermoluminescence (TL) of meteorites reflects their irradiation and thermal histories. Virtually all ordinary chondrites have been irradiated long enough to reach saturation natural TL levels, and thus natural TL levels in these meteorites are determined largely by thermal history. The primary heat source for most meteorites is the Sun, and thus natural TL levels are determined primarily by the closest approach to the Sun, i.e., perihelion. By converting natural TL levels to perihelia, using an assumed albedo typical of meteoroid bodies, it is found that most ordinary chondrites had perihelia of 0.85 to 1.0 AU prior to reaching Earth. This range is similar to that calculated from meteor and fireball observations. All common classes of ordinary chondrites exhibit similar perihelia distributions; however, H and LL chondrites that fell in the local morning differ in their natural TL distribution from those that fell in the local afternoon or evening. This is consistent with earlier suggestions that time of fall reflects orbital distribution. The data also suggest that the orbits of some of the H chondrites cluster and may have come from a debris 'stream' of meteoroids. If meteorites can exist in "orbital groups," significant changes in the types and number of meteorites reaching Earth could occur on the less than 10(exp 5)-year time scale.

Framework for Leadership and Training of Biosafety Level 4 Laboratory Workers

PubMed Central

Anderson, Kevin; Bloom, Marshall E.; Estep, James E.; Feldmann, Heinz; Geisbert, Joan B.; Geisbert, Thomas W.; Hensley, Lisa; Holbrook, Michael; Jahrling, Peter B.; Ksiazek, Thomas G.; Korch, George; Patterson, Jean; Skvorak, John P.; Weingartl, Hana

2008-01-01

Construction of several new Biosafety Level 4 (BSL-4) laboratories and expansion of existing operations have created an increased international demand for well-trained staff and facility leaders. Directors of most North American BSL-4 laboratories met and agreed upon a framework for leadership and training of biocontainment research and operations staff. They agreed on essential preparation and training that includes theoretical consideration of biocontainment principles, practical hands-on training, and mentored on-the-job experiences relevant to positional responsibilities as essential preparation before a person’s independent access to a BSL-4 facility. They also agreed that the BSL-4 laboratory director is the key person most responsible for ensuring that staff members are appropriately prepared for BSL-4 operations. Although standardized certification of training does not formally exist, the directors agreed that facility-specific, time-limited documentation to recognize specific skills and experiences of trained persons is needed. PMID:18976549

Unfolding neutron spectra from simulated response of thermoluminescence dosimeters inside a polyethylene sphere using GRNN neural network

NASA Astrophysics Data System (ADS)

Lotfalizadeh, F.; Faghihi, R.; Bahadorzadeh, B.; Sina, S.

2017-07-01

Neutron spectrometry using a single-sphere containing dosimeters has been developed recently, as an effective replacement for Bonner sphere spectrometry. The aim of this study is unfolding the neutron energy spectra using GRNN artificial neural network, from the response of thermoluminescence dosimeters, TLDs, located inside a polyethylene sphere. The spectrometer was simulated using MCNP5. TLD-600 and TLD-700 dosimeters were simulated at different positions in all directions. Then the GRNN was used for neutron spectra prediction, using the TLDs' readings. Comparison of spectra predicted by the network with the real spectra, show that the single-sphere dosimeter is an effective instrument in unfolding neutron spectra.

Evaluation and Adaptation of a Laboratory-Based cDNA Library Preparation Protocol for Retrospective Sequencing of Archived MicroRNAs from up to 35-Year-Old Clinical FFPE Specimens

PubMed Central

Loudig, Olivier; Wang, Tao; Ye, Kenny; Lin, Juan; Wang, Yihong; Ramnauth, Andrew; Liu, Christina; Stark, Azadeh; Chitale, Dhananjay; Greenlee, Robert; Multerer, Deborah; Honda, Stacey; Daida, Yihe; Spencer Feigelson, Heather; Glass, Andrew; Couch, Fergus J.; Rohan, Thomas; Ben-Dov, Iddo Z.

2017-01-01

Formalin-fixed paraffin-embedded (FFPE) specimens, when used in conjunction with patient clinical data history, represent an invaluable resource for molecular studies of cancer. Even though nucleic acids extracted from archived FFPE tissues are degraded, their molecular analysis has become possible. In this study, we optimized a laboratory-based next-generation sequencing barcoded cDNA library preparation protocol for analysis of small RNAs recovered from archived FFPE tissues. Using matched fresh and FFPE specimens, we evaluated the robustness and reproducibility of our optimized approach, as well as its applicability to archived clinical specimens stored for up to 35 years. We then evaluated this cDNA library preparation protocol by performing a miRNA expression analysis of archived breast ductal carcinoma in situ (DCIS) specimens, selected for their relation to the risk of subsequent breast cancer development and obtained from six different institutions. Our analyses identified six miRNAs (miR-29a, miR-221, miR-375, miR-184, miR-363, miR-455-5p) differentially expressed between DCIS lesions from women who subsequently developed an invasive breast cancer (cases) and women who did not develop invasive breast cancer within the same time interval (control). Our thorough evaluation and application of this laboratory-based miRNA sequencing analysis indicates that the preparation of small RNA cDNA libraries can reliably be performed on older, archived, clinically-classified specimens. PMID:28335433

Bill Kerslake Preparing a Test in the Rocket Laboratory

NASA Image and Video Library

1952-10-21

William Kerslake, a combustion researcher at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory, examines the setup of a transparent rocket in a Rocket Laboratory test cell. Kerslake joined NACA Lewis the previous summer after graduating from the Case Institute of Technology with a chemistry degree. His earliest professional research concentrated on combustion instability in small rocket engines. While at Case the quiet, 250-pound Kerslake also demonstrated his athletic prowess on the wrestling team. He continued wrestling for roughly a decade afterwards while conducting his research with the NACA. Kerslake participated in Olympic competitions in Helsinki (1952), Melbourne (1956), and Rome (1960). He won 30 national championships in three different weight classes and captured the gold at the 1955 Pan American Games in Mexico City. Kerslake accomplished all this while maintaining his research career, raising a family, and paying his own expenses. As his wrestling career was winding down in the early 1960s, Kerslake’s professional career changed, as well. He was transferred to Harold Kaufman’s Electrostatic Propulsion Systems Section in the new Electromagnetic Propulsion Division. Kaufman was developing the first successful ion engine at the time, and Kerslake spent the remainder of his career working in the electric propulsion field. He was heavily involved in the two Space Electric Rocket Test (SERT) missions which demonstrated that the ion thrusters could successfully operate in space. Kerslake retired in 1985 with over 30 years of service.

222-S Laboratory Quality Assurance Plan. Revision 1

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

Meznarich, H.K.

1995-07-31

This Quality Assurance Plan provides,quality assurance (QA) guidance, regulatory QA requirements (e.g., 10 CFR 830.120), and quality control (QC) specifications for analytical service. This document follows the U.S Department of Energy (DOE) issued Hanford Analytical Services Quality Assurance Plan (HASQAP). In addition, this document meets the objectives of the Quality Assurance Program provided in the WHC-CM-4-2, Section 2.1. Quality assurance elements required in the Guidelines and Specifications for Preparing Quality Assurance Program Plans (QAMS-004) and Interim Guidelines and Specifications for Preparing Quality Assurance Project Plans (QAMS-005) from the US Environmental Protection Agency (EPA) are covered throughout this document. A qualitymore » assurance index is provided in the Appendix A. This document also provides and/or identifies the procedural information that governs laboratory operations. The personnel of the 222-S Laboratory and the Standards Laboratory including managers, analysts, QA/QC staff, auditors, and support staff shall use this document as guidance and instructions for their operational and quality assurance activities. Other organizations that conduct activities described in this document for the 222-S Laboratory shall follow this QA/QC document.« less

An Integrated Laboratory Approach toward the Preparation of Conductive Poly(phenylene vinylene) Polymers

ERIC Educational Resources Information Center

Knoerzer, Timm A.; Balaich, Gary J.; Miller, Hannah A.; Iacono, Scott T.

2014-01-01

Poly(phenylene vinylene) (PPV) represents an important class of conjugated, conducting polymers that have been readily exploited in the preparation of organic electronic materials. In this experiment, students prepare a PPV polymer via a facile multistep synthetic sequence with robust spectroscopic evaluation of synthetic intermediates and the…

Laboratory diagnostics of malaria

NASA Astrophysics Data System (ADS)

Siahaan, L.

2018-03-01

Even now, malaria treatment should only be administered after laboratory confirmation. There are several principal methods for diagnosing malaria. All these methods have their disadvantages.Presumptive treatment of malaria is widely practiced where laboratory tests are not readily available. Microscopy of Giemsa-stained thick and thin blood films remains the gold standard for the diagnosis of malaria infection. The technique of slide preparation, staining and reading are well known and standardized, and so is the estimate of the parasite density and parasite stages. Microscopy is not always available or feasible at primary health services in limited resource settings due to cost, lack of skilled manpower, accessories and reagents required. Rapid diagnostic tests (RDTs) are potential tools for parasite-based diagnosis since the tests are accurate in detecting malaria infections and are easy to use. The test is based on the capture of parasite antigen that released from parasitized red blood cells using monoclonal antibodies prepared against malaria antigen target. Polymerase Chain Reaction (PCR), depend on DNA amplification approaches and have higher sensitivity than microscopy. PCR it is not widely used due to the lack of a standardized methodology, high costs, and the need for highly-trained staff.

Implementing self sustained quality control procedures in a clinical laboratory.

PubMed

Khatri, Roshan; K C, Sanjay; Shrestha, Prabodh; Sinha, J N

2013-01-01

Quality control is an essential component in every clinical laboratory which maintains the excellence of laboratory standards, supplementing to proper disease diagnosis, patient care and resulting in overall strengthening of health care system. Numerous quality control schemes are available, with combinations of procedures, most of which are tedious, time consuming and can be "too technical" whereas commercially available quality control materials can be expensive especially for laboratories in developing nations like Nepal. Here, we present a procedure performed at our centre with self prepared control serum and use of simple statistical tools for quality assurance. The pooled serum was prepared as per guidelines for preparation of stabilized liquid quality control serum from human sera. Internal Quality Assessment was performed on this sample, on a daily basis which included measurement of 12 routine biochemical parameters. The results were plotted on Levey-Jennings charts and analysed with quality control rules, for a period of one month. The mean levels of biochemical analytes in self prepared control serum were within normal physiological range. This serum was evaluated every day along with patients' samples. The results obtained were plotted on control charts and analysed using common quality control rules to identify possible systematic and random errors. Immediate mitigation measures were taken and the dispatch of erroneous reports was avoided. In this study we try to highlight on a simple internal quality control procedure which can be performed by laboratories, with minimum technology, expenditure, and expertise and improve reliability and validity of the test reports.

Cruise Stage Testing for Mars Science Laboratory

NASA Image and Video Library

2010-09-02

Testing of the cruise stage for NASA Mars Science Laboratory in August 2010 included a session in a facility that simulates the environment found in interplanetary space. Spacecraft technicians at JPL prepare a space-simulation test.

Viability testing of material derived from Mycobacterium tuberculosis prior to removal from a Containment Level-III Laboratory as part of a Laboratory Risk Assessment Program

PubMed Central

Blackwood, Kym S; Burdz, Tamara V; Turenne, Christine Y; Sharma, Meenu K; Kabani, Amin M; Wolfe, Joyce N

2005-01-01

Background In the field of clinical mycobacteriology, Mycobacterium tuberculosis (MTB) can be a difficult organism to manipulate due to the restrictive environment of a containment level 3 (CL3) laboratory. Tests for rapid diagnostic work involving smears and molecular methods do not require CL3 practices after the organism has been rendered non-viable. While it has been assumed that after organism deactivation these techniques can be performed outside of a CL3, no conclusive study has consistently confirmed that the organisms are noninfectious after the theoretical 'deactivation' steps. Previous studies have shown that initial steps (such as heating /chemical fixation) may not consistently kill MTB organisms. Methods An inclusive viability study (n = 226) was undertaken to determine at which point handling of culture extraction materials does not necessitate a CL3 environment. Four different laboratory protocols tested for viability included: standard DNA extractions for IS6110 fingerprinting, crude DNA preparations for PCR by boiling and mechanical lysis, protein extractions, and smear preparations. For each protocol, laboratory staff planted a proportion of the resulting material to Bactec 12B medium that was observed for growth for 8 weeks. Results Of the 208 isolates initially tested, 21 samples grew within the 8-week period. Sixteen (7.7%) of these yielded positive results for MTB that included samples of: deactivated culture resuspensions exposed to 80°C for 20 minutes, smear preparations and protein extractions. Test procedures were consequently modified and tested again (n = 18), resulting in 0% viability. Conclusions This study demonstrates that it cannot be assumed that conventional practices (i.e. smear preparation) or extraction techniques render the organism non-viable. All methodologies, new and existing, should be examined by individual laboratories to validate the safe removal of material derived from MTB to the outside of a CL3 laboratory. This

Viability testing of material derived from Mycobacterium tuberculosis prior to removal from a containment level-III laboratory as part of a Laboratory Risk Assessment Program.

PubMed

Blackwood, Kym S; Burdz, Tamara V; Turenne, Christine Y; Sharma, Meenu K; Kabani, Amin M; Wolfe, Joyce N

2005-01-24

In the field of clinical mycobacteriology, Mycobacterium tuberculosis (MTB) can be a difficult organism to manipulate due to the restrictive environment of a containment level 3 (CL3) laboratory. Tests for rapid diagnostic work involving smears and molecular methods do not require CL3 practices after the organism has been rendered non-viable. While it has been assumed that after organism deactivation these techniques can be performed outside of a CL3, no conclusive study has consistently confirmed that the organisms are noninfectious after the theoretical 'deactivation' steps. Previous studies have shown that initial steps (such as heating/chemical fixation) may not consistently kill MTB organisms. An inclusive viability study (n = 226) was undertaken to determine at which point handling of culture extraction materials does not necessitate a CL3 environment. Four different laboratory protocols tested for viability included: standard DNA extractions for IS6110 fingerprinting, crude DNA preparations for PCR by boiling and mechanical lysis, protein extractions, and smear preparations. For each protocol, laboratory staff planted a proportion of the resulting material to Bactec 12B medium that was observed for growth for 8 weeks. Of the 208 isolates initially tested, 21 samples grew within the 8-week period. Sixteen (7.7%) of these yielded positive results for MTB that included samples of: deactivated culture resuspensions exposed to 80 degrees C for 20 minutes, smear preparations and protein extractions. Test procedures were consequently modified and tested again (n = 18), resulting in 0% viability. This study demonstrates that it cannot be assumed that conventional practices (i.e. smear preparation) or extraction techniques render the organism non-viable. All methodologies, new and existing, should be examined by individual laboratories to validate the safe removal of material derived from MTB to the outside of a CL3 laboratory. This process is vital to establish in

Medical Service Clinical Laboratory Procedures--Bacteriology.

ERIC Educational Resources Information Center

Department of the Army, Washington, DC.

This manual presents laboratory procedures for the differentiation and identification of disease agents from clinical materials. Included are procedures for the collection of specimens, preparation of culture media, pure culture methods, cultivation of the microorganisms in natural and simulated natural environments, and procedures in…

WHO Expert Committee on Specifications for Pharmaceutical Preparations.

PubMed

2011-01-01

The Expert Committee on Specifications for Pharmaceutical Preparations works towards clear, independent and practical standards and guidelines for the quality assurance of medicines. Standards are developed by the Committee through worldwide consultation and an international consensus-building process. The following new guidelines were adopted and recommended for use: procedure for adoption of International Chemical Reference Substances; WHO good practices for pharmaceutical microbiology laboratories; good manufacturing practices: main principles for pharmaceutical products; good manufacturing practices for blood establishments (jointly with the Expert Committee on Biological Standardization); guidelines on good manufacturing practices for heating, ventilation and air-conditioning systems for non-sterile pharmaceutical dosage forms; good manufacturing practices for sterile pharmaceutical products; guidelines on transfer of technology in pharmaceutical manufacturing; good pharmacy practice: standards for quality of pharmacy services (joint FIP/WHO); model guidance for the storage and transport of time- and temperature-sensitive pharmaceutical products (jointly with the Expert Committee on Biological Standardization); procedure for prequalification of pharmaceutical products; guide on submission of documentation for prequalification of innovator finished pharmaceutical products approved by stringent regulatory authorities; prequalification of quality control laboratories: procedure for assessing the acceptability, in principle, of quality control laboratories for use by United Nations agencies; guidelines for preparing a laboratory information file; guidelines for drafting a site master file; guidelines on submission of documentation for a multisource (generic) finished product: general format: preparation of product dossiers in common technical document format.

Nomenclature in laboratory robotics and automation (IUPAC Recommendation 1994)

PubMed Central

(Skip) Kingston, H. M.; Kingstonz, M. L.

1994-01-01

These recommended terms have been prepared to help provide a uniform approach to terminology and notation in laboratory automation and robotics. Since the terminology used in laboratory automation and robotics has been derived from diverse backgrounds, it is often vague, imprecise, and in some cases, in conflict with classical automation and robotic nomenclature. These dejinitions have been assembled from standards, monographs, dictionaries, journal articles, and documents of international organizations emphasizing laboratory and industrial automation and robotics. When appropriate, definitions have been taken directly from the original source and identified with that source. However, in some cases no acceptable definition could be found and a new definition was prepared to define the object, term, or action. Attention has been given to defining specific robot types, coordinate systems, parameters, attributes, communication protocols and associated workstations and hardware. Diagrams are included to illustrate specific concepts that can best be understood by visualization. PMID:18924684

[Procedure for Latrodectus reproduction in the laboratory setting and the preparation of the first Russian matrix from its venom to manufacture homeopathic remedies with antiparasitic activity].

PubMed

Streliaeva, A V; Gasparian, E R; Polzikov, V V; Sagieva, A T; Lazareva, N B; Kurilov, D V; Chebyshev, N V; Sadykov, V M; Zuev, S S; Shcheglova, T A

2012-01-01

The investigation was undertaken to study the biology and ecology of Latrodectus, the possibilities of its importation to Russia from other countries, to breed Latrodectus in the laboratory setting, and to design the first homeopathic matrix of Latrodectus to manufacture homeopathic remedies. The authors were the first to devise a method for Latrodectus breeding in the laboratory setting of Moscow and its vicinities. The Latrodectus bred in the laboratory is suitable to manufacture drugs and in captivity they do not lose its biological activity. The authors were the first to prepare a homeopathic Latrodectus matrix for homeopathic medicines, by using the new Russian extragent petroleum. Chromatography mass spectrometry was used to identify more than a hundred chemical compounds in the Russian petroleum. The biological activity of the petroleum Latrodectus matrix for the manufacture of homeopathic remedies was highly competitive with that of the traditional Latrodectus venom matrix made using ethyl alcohol. The homeopathic Latrodectus matrix made using glycerol lost its biological activity because of glycerol. The biological activity of homeopathic matrixes made from Latrodectus inhabiting the USA, Uzbekistan, and the south of Russia and from that bred in the laboratory was studied. The homeopathic matrix made from the Latrodectus living in the Samarkand Region, Republic of Uzbekistan, has the highest biological activity.

Electrical and thermoluminescence properties of γ-irradiated La2CuO4 crystals

NASA Astrophysics Data System (ADS)

El-Kolaly, M. A.; Abd El-Kader, H. I.; Kassem, M. E.

1994-12-01

Measurements of the electrical properties of unirradiated as well as ?-irradiated La2CuO4 crystals were carried out at different temperatures in the frequency range of 0.1-100 kHz. Thermoluminescence (TL) studies were also performed on such crystals in the temperature range of 300-600K. The conductivity of the unirradiated La2CuO4 crystals were found to obey the power law frequency dependence at each measured temperature below the transition temperature (Tc = 450K). The activation energies for conduction and dielectric relaxation time have been calculated. The TL response and the dc resistance were found to increase with ?-irradiation dose up to 9-10 kGy. The results showed that the ferroelastic domain walls of La2CuO4 crystal as well as its TL traps are sensitive to ?-raditaion. This material can be used in radiation measurements in the range 225 Gy-10 kGy.

ZrO2:Sm3+ nanophosphor: synthesis, Rietveld refinement, optical and thermoluminescent properties

NASA Astrophysics Data System (ADS)

Ponkumar, S.; Janaki, K.; Prakashbabu, D.; Ramalingam, H. B.; Munirathnam, K.; Sreekanth, T. V. M.; Dhoble, S. J.

2018-02-01

We have synthesized undoped and Sm3+ ions doped ZrO2 nanophosphors by solution combustion method. These nanophosphors crystallized in cubic structure. Rietveld refinement of the samples was performed to estimate lattice parameters. Spherical particles with the sizes of 10-25 nm were observed by transmission electron microscopy. Photoluminescence and thermoluminescence (TL) properties of samples were investigated. Under 400 nm excitation, the nanophosphors have intense red emission at 600 nm. The color coordinates (0.67, 0.33) were located in the red region of CIE diagram. TL properties of nanophosphors were studied by exposing the samples to γ-rays. 5 mol% Sm3+ doped ZrO2 nanophosphor has shown maximum TL intensity after γ-irradiation. To test suitability of the nanophosphors for practical application in dosimetry, the 5 mol% Sm3+ doped ZrO2 sample was irradiated by 14 MeV electron beam in various electron fluence ranging from 100 to 900 Gy and their TL response was recorded.

The Thermoluminescence Response of Ge-Doped Flat Fibers to Gamma Radiation

PubMed Central

Mat Nawi, Siti Nurasiah Binti; Wahib, Nor Fadira Binti; Zulkepely, Nurul Najua Binti; Amin, Yusoff Bin Mohd; Min, Ung Ngie; Bradley, David Andrew; Md Nor, Roslan Bin; Maah, Mohd Jamil

2015-01-01

Study has been undertaken of the thermoluminescence (TL) yield of various tailor-made flat cross-section 6 mol% Ge-doped silica fibers, differing only in respect of external dimensions. Key TL dosimetric characteristics have been investigated, including glow curves, dose response, sensitivity, fading and reproducibility. Using a 60Co source, the samples were irradiated to doses within the range 1 to 10 Gy. Prior to irradiation, the flat fibers were sectioned into 6 mm lengths, weighed, and annealed at 400 °C for 1 h. TL readout was by means of a Harshaw Model 3500 TLD reader, with TLD-100 chips (LiF:Mg, Ti) used as a reference dosimeter to allow the relative response of the fibers to be evaluated. The fibers have been found to provide highly linear dose response and excellent reproducibility over the range of doses investigated, demonstrating high potential as TL-mode detectors in radiation medicine applications. Mass for mass, the results show the greatest TL yield to be provided by fibers of the smallest cross-section, analysis indicating this to be due to minimal light loss in transport of the TL through the bulk of the silica medium. PMID:26307987

Laboratory Safety Needs of Kentucky School-Based Agricultural Mechanics Teachers

ERIC Educational Resources Information Center

Saucier, P. Ryan; Vincent, Stacy K.; Anderson, Ryan G.

2014-01-01

The frequency and severity of accidents that occur in the agricultural mechanics laboratory can be reduced when these facilities are managed by educators who are competent in the area of laboratory safety and facility management (McKim & Saucier, 2011). To ensure teachers are technically competent and prepared to manage an agricultural…

21 CFR 58.185 - Reporting of nonclinical laboratory study results.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Reporting of nonclinical laboratory study results. 58.185 Section 58.185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Reporting of nonclinical laboratory study results. (a) A final report shall be prepared for each nonclinical...

21 CFR 58.185 - Reporting of nonclinical laboratory study results.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Reporting of nonclinical laboratory study results. 58.185 Section 58.185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Reporting of nonclinical laboratory study results. (a) A final report shall be prepared for each nonclinical...

21 CFR 58.185 - Reporting of nonclinical laboratory study results.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Reporting of nonclinical laboratory study results. 58.185 Section 58.185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Reporting of nonclinical laboratory study results. (a) A final report shall be prepared for each nonclinical...

The thermoluminescence study of epoxy based LiF:Mg,Cu,P dosimeters

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

Rahangdale, S. R., E-mail: sachin.rahangdale1@gmail.com; Palikundwar, U. A.; Moharil, S. V.

The LiF:Mg,Cu,P phosphor is the most investigated phosphor in radiation dosimetry. Results on thermoluminescence of the epoxy based LiF:Mg,Cu,P dosimeters irradiated with gamma radiations are presented and compared with results of LiF:Mg,Cu,P powder. The glow curve structure of both LiF powder and dosimeter are same and only difference is found in the glow curve peak temperature. The LiF dosimeters were made from the 5012A and 5012B epoxy. The dosimeters had a mass of about 18 mg, 5.0 mm diameter and 0.5 mm thickness. The sensitivity variation of the dosimeters for exposure to {sup 60}Co gamma rays at different angles of incidence of themore » radiation is found to be within 4%. Its minimum detectable dose is about 3020 µGy. The epoxy based dosimeters withstand different environment and it can be used with general TL reader without need of any special design due to its small size and plane surface.« less

Laboratory investigations

NASA Technical Reports Server (NTRS)

Russell, Ray W.

1988-01-01

Laboratory studies related to cometary grains and the nuclei of comets can be broken down into three areas which relate to understanding the spectral properties, the formation mechanisms, and the evolution of grains and nuclei: (1) Spectral studies to be used in the interpretation of cometary spectra; (2) Sample preparation experiments which may shed light on the physical nature and history of cometary grains and nuclei by exploring the effects on grain emissivities resulting from the ways in which the samples are created; and (3) Grain processing experiments which should provide insight on the interaction of cometary grains with the environment in the immediate vicinity of the cometary nucleus as the comet travels from the Oort cloud through perihelion, and perhaps even suggestions regarding the relationship between interstellar grains and cometary matter. A summary is presented with a different view of lab experiments than is found in the literature, concentrating on measurement techniques and sample preparations especially relevant to cometary dust.

Forest Products Laboratory natural finish

Treesearch

J. M. Black; D. F. Laughnan; E. A. Mraz

1979-01-01

A simple and durable exterior natural finish developed at the Forest Products Laboratory is described. The finish is classified as a semi-transparent oil-base penetrating stain that effectively retains much of the natural grain and texture of wood when exposed to the weather. The directions for preparation are included as are the recommendations for application to both...

Lighting up Protons with MorphFl, a Fluorescein-Morpholine Dyad: An Experiment for the Organic Laboratory

ERIC Educational Resources Information Center

Miller, Tyson A.; Spangler, Michael; Burdette, Shawn C.

2011-01-01

A two-period organic laboratory experiment that includes fluorescence sensing is presented. The pH-sensitive sensor MorphFl is prepared using a Mannich reaction between a fluorescein derivative and the iminium ion of morpholine. During the first laboratory, students prepare MorphFl. The second session begins with characterizing the sensor using…

The use of in vivo thermoluminescent dosimeters in the quality assurance programme for the START breast fractionation trial.

PubMed

Venables, Karen; Miles, Elizabeth A; Aird, Edwin G A; Hoskin, Peter J

2004-06-01

The use of in vivo dosimetry for patient measurement is recommended in many publications. It provides an additional check to verify that the dose delivered to the patient corresponds to the prescribed dose. In the context of a clinical trial investigating the effects of different fractionation regimens, it is imperative that the dose given is that prescribed to ensure that noise in the data between centres does not mask the results of the trial. The methodology for in vivo measurement in a clinical trial of breast radiotherapy was developed and verified. A cohort of patients in the STAndardisation of breast RadioTherapy (START) trial was monitored using postal thermoluminescent dosimeters chips (TLD). All TLD were processed and analysed at Mount Vernon Hospital. Patients for in vivo measurements were identified at randomisation as a random 1 in 9 samples for the first 2500 patients randomised (282 TLD) increasing to 1 in 3 thereafter. The TLD were left in place for the duration of the tangential field treatment and thus a composite entrance and exit dose was recorded. TLD measurements were performed on 429 patients from 33 hospitals. The average ratio of dose measured using TLD to that prescribed was 0.99+/-0.04. Eight patients had initial measurements more than 10% different to the prescribed dose. The mean TLD results for a given centre correlated well with dose measurements performed using an ionisation chamber in a breast shaped phantom at that centre as part of the START trial audit. Thermoluminescence dosimetry has provided useful quality assurance information on the doses received by patients in centres participating in the START trial.

Thermoluminescence and the shock and reheating history of meteorites. IV - The induced TL properties of type 4-6 ordinary chondrites

NASA Technical Reports Server (NTRS)

Haq, Munir; Hasan, Fouad A.; Sears, Derek W. G.

1988-01-01

The thermoluminescence (TL) properties were measured in 121 equilibrated H and L ordinary chondrites of which 33 H and 32 L were from Antarctica. It was found that the distribution of TL sensitivities for non-Antarctic L chondrites differs from that of non-Antarctic H chondrites, reflecting the well-known differences in shock history between L and H classes, the greater proportion of the former having suffered postmetamorphic shock. The data also show differences in TL sensitivity between Antarctic and non-Antarctic H chondrites, suggesting nontrivial differences in thermal history of these chondrites.

Developing Laboratory Skills by Incorporating Peer-Review and Digital Badges

ERIC Educational Resources Information Center

Seery, Michael K.; Agustian, Hendra Y.; Doidge, Euan D.; Kucharski, Maciej M.; O'Connor, Helen M.; Price, Amy

2017-01-01

Laboratory work is at the core of any chemistry curriculum but literature on the assessment of laboratory skills is scant. In this study we report the use of a peer-observation protocol underpinned by exemplar videos. Students are required to watch exemplar videos for three techniques (titrations, distillations, preparation of standard solutions)…

Application of radioisotope XRF and thermoluminescence (TL) dating in investigation of pottery from Tell AL-Kasra archaeological site, Syria.

PubMed

Abboud, R; Issa, H; Abed-Allah, Y D; Bakraji, E H

2015-11-01

Statistical analysis based on chemical composition, using radioisotope X-ray fluorescence, have been applied on 39 ancient pottery fragments coming from the excavation at Tell Al-Kasra archaeological site, Syria. Three groups were defined by applying Cluster and Factor analysis statistical methods. Thermoluminescence (TL) dating was investigated on three sherds taken from the bathroom (hammam) on the site. Multiple aliquot additive dose (MAAD) was used to estimate the paleodose value, and the gamma spectrometry was used to estimate the dose rate. The average age was found to be 715±36 year. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental Assessment, Balloon Launch and Landing Operations, Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico

DTIC Science & Technology

2012-06-01

Force Research Laboratory , Space Vehicles Directorate ( AFRL /RV) located at Kirtland Air Force Base is preparing an Environmental Assessment (EA) for...United States Air Force Research Laboratory , Space Vehicles Directorate ( AFRL /RV) located at Kirtland Air Force Base is preparing an Environmental...United States Air Force Research Laboratory , Space Vehicles Directorate ( AFRL

Thermoluminescence glow-curve characteristics of LiF phosphors at high doses of gamma radiation

NASA Astrophysics Data System (ADS)

Benny, P. G.; Khader, S. A.; Sarma, K. S. S.

2013-05-01

High doses of ionising radiation are becoming increasingly common for radiation-processing applications of various medical, agricultural and polymer products using gamma and electron beams. The objective of this work was to study thermoluminescence (TL) glow-curve characteristics of commonly used commercial LiF TL phosphors at high doses of radiation with a view to use them in dosimetry of radiation-processing applications. The TL properties of TLD 100 and 700 phosphors, procured from the Thermo-Scientific (previously Harshaw) company, have been studied in the dose range of 1-60 kGy. The shift in glow peaks was observed in this dose range. Integral TL responses of TLD 100 and TLD 700 were found to decrease as a linear function of dose in the range of 5-50 kGy. The paper describes initial results related to the glow-curve characteristics of these phosphors.

Antinuclear antibody determination in a routine laboratory.

PubMed Central

Feltkamp, T E

1996-01-01

Pitfalls in the method for demonstrating antinuclear antibodies (ANA) by the indirect immunofluorescence technique are described and the use of international standard preparations outlined. Determination of the optimal border dilution dividing positive from negative results is discussed. Each laboratory is a unique setting; it must define its own method, which should rarely be changed. One should not rely on copying methods from other laboratories or commercial firms, but the reproducibility of the nuclear substrate, the conjugate, and other variables should be controlled daily by the use of a control serum which has been related to the WHO standard preparation for ANA of the homogeneous type. Since many sera contain mixtures of different ANA, the results of routine tests are best expressed in titres or expressions of the intensity of fluorescence. The ANA test using the immunofluorescence technique should be used as a screening method for other tests allowing a more defined interpretation of the ANA. Each laboratory should individually determine the border between positive and negative results. Therefore about 200 sera from local healthy controls equally distributed over sex and age, and 100 sera from local patients with definite SLE should be tested. Since the local clinicians should become acquainted with this border it should rarely be changed. Finally each laboratory should participate regularly in national and international quality control rounds, where sera known to be difficult to interpret are tested. The judgment of the organisers of these rounds should stimulate improvements in the participating laboratories. PMID:8984936

Thermoluminescence properties of Li2B4O7:Cu, B phosphor synthesized using solution combustion technique

NASA Astrophysics Data System (ADS)

Ozdemir, A.; Altunal, V.; Kurt, K.; Depci, T.; Yu, Y.; Lawrence, Y.; Nur, N.; Guckan, V.; Yegingil, Z.

2017-12-01

To determine the effects of various concentrations of the activators copper (Cu) and boron (B) on the thermoluminescence (TL) properties of lithium tetraborate, the phosphor was first synthesized and doped with five different concentrations of copper (0.1-0.005 wt%) using solution combustion method. 0.01 wt% Cu was the concentration which showed the most significant increase in the sensitivity of the phosphor. The second sort of Li2B4O7:Cu material was prepared by adding B (0.001-0.03 wt%) to it. The newly developed copper-boron activated lithium tetraborate (Li2B4O7:Cu, B) material with 0.01 wt% Cu and 0.001 wt% B impurity concentrations was shown to have promise as a TL phosphor. The material formation was examined using powder x-Ray Diffraction (XRD) analysis and Scanning Electron Microscope (SEM) imaging. Fourier Transform Infrared (FT-IR) spectrum of the synthesized polycrystalline powder sample was also recorded. The TL glow curves were analyzed to determine various dosimetric characteristics of the synthesized luminophosphors. The dose response increased in a ;linear; way with the beta-ray exposure between 0.1-20 Gy, a dose range being interested in medical dosimetry. The response with changing photon and electron energy was studied. The rate of decay of the TL signal was investigated both for dark storage and under direct sunlight. Li2B4O7:Cu, B showed no individual variation of response in 9 recycling measurements. The fluorescence spectrum was determined. The kinetic parameters were estimated by different methods and the results discussed. The studied properties of synthesized Li2B4O7:Cu, B were found all favorable for dosimetric purposes.

Preparation for Testing of Mars Landing Radar

NASA Image and Video Library

2010-04-13

This image taken March 25, 2010 shows preparations for radar testing for NASA Mars Science Laboratory. This day work evaluated a setup for suspending a rover mock-up beneath a helicopter at Hawthorne Municipal Airport, Hawthorne, Calif.

Integration of Simulation into Pre-Laboratory Chemical Course: Computer Cluster versus WebCT

ERIC Educational Resources Information Center

Limniou, Maria; Papadopoulos, Nikos; Whitehead, Christopher

2009-01-01

Pre-laboratory activities have been known to improve students' preparation before their practical work as they assist students to make available more working memory capacity for actual learning during the laboratory. The aim of this investigation was to compare two different teaching approaches which supported a pre-laboratory session by using the…

CaSO4:DY,Mn: A new and highly sensitive thermoluminescence phosphor for versatile dosimetry

NASA Astrophysics Data System (ADS)

Bahl, Shaila; Lochab, S. P.; Kumar, Pratik

2016-02-01

With the advent of newer techniques for dose reduction coupled with the development of more sensitive detectors, the radiation doses in radiological medical investigation are decreasing. Nevertheless, keeping the tenet in mind that all radiation doses could entail risk, there is a need to develop more sensitive dosimeters capable of measuring low doses. This paper gives the account of the development of a new and sensitive phosphor CaSO4:Dy,Mn and its characterization. The standard production procedure based on the recrystallization method was used to prepare CaSO4:Dy,Mn. The Thermoluminescence (TL) studies were carried out by exposing it with gamma radiation (Cs-137) from 10 μGy to 100 Gy. The theoretical studies to determine the number of peaks and kinetic parameters related to the TL glow peaks in CaSO4:Dy,Mn was performed using the Computerized Glow Curve Deconvolution (CGCD) method. Experiments were performed to determine optimum concentration of the dopants Dysprosium (Dy) and Mangnese (Mn) in the host CaSO4 so that maximum sensitivity of the phosphor may be achieved. The optimum dopant concentration turned out to be 0.1 mol%. As there were two dopants Dy and Mn their relative ratio were varied in steps of 0.025 keeping the concentration of total dopant (Dy and Mn) 0.1 mol% always. The maximum TL intensity was seen in the CaSO4:Dy(0.025),Mn(0.075) combination. The TL sensitivity of this phosphor was found to be about 2 and 1.8 times higher than that of popular phosphor CaSO4:Dy and LiF:Mg,Cu,P (TLD-700H) respectively. This new phosphor CaSO4:Dy,Mn showed fading of 11% which is similar to that of the standard phosphor CaSO4:Dy. The paper concludes that the new, highly sensitive TL phosphor CaSO4:Dy,Mn has shown higher sensitivity and hence the potential to replace commonly used CaSO4:Dy.

Statistical analysis of the calibration procedure for personnel radiation measurement instruments

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

Bush, W.J.; Bengston, S.J.; Kalbeitzer, F.L.

1980-11-01

Thermoluminescent analyzer (TLA) calibration procedures were used to estimate personnel radiation exposure levels at the Idaho National Engineering Laboratory (INEL). A statistical analysis is presented herein based on data collected over a six month period in 1979 on four TLA's located in the Department of Energy (DOE) Radiological and Environmental Sciences Laboratory at the INEL. The data were collected according to the day-to-day procedure in effect at that time. Both gamma and beta radiation models are developed. Observed TLA readings of thermoluminescent dosimeters are correlated with known radiation levels. This correlation is then used to predict unknown radiation doses frommore » future analyzer readings of personnel thermoluminescent dosimeters. The statistical techniques applied in this analysis include weighted linear regression, estimation of systematic and random error variances, prediction interval estimation using Scheffe's theory of calibration, the estimation of the ratio of the means of two normal bivariate distributed random variables and their corresponding confidence limits according to Kendall and Stuart, tests of normality, experimental design, a comparison between instruments, and quality control.« less

Molybdenum-99 Isotope Production Preparation at Sandia National Laboratories

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

Carson, S.D.; Longley, S.W.; McDonald, M.J.

`Q&c M. J. McDonald, S. D. Carson, S. W. Longley, E. J. Parma, M. E. Vern `~ I@ .,., Sandia National Laboratories*, P. .0. Box 5800, Albuquerque, NM, 8 W? 1$ tl?;:q `f. (3 . 8 /'~ Abstract This report was prepared as an account of work sponsored byanagency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its usemore » would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. loading on the Cintichem targets. These tests were designed to gain process knowledge prior to processing an irradiated target. The chemical separation tests were performed in a fime hood During cold testing, several tests were performed on individual components of the process to complete, a series of `hot' tests was designed to process irradiated targets. These were designed to optimize the process, identify problems prior to processing higher inventory targets, and to the shielded containment box (SCB). Table 1 is a summary of the tests performed prior to the Test Target Power Post irradiation Total inventory 99M0 inventory (kW)/ Irradiation decay (hrs) (TBq*) /decay (TBq)/decay Time (hrs) inventory (TBq) inventory(TBq) in the processing boxes as color comparisons. Product quality control testing was conducted for all the tests and the results were compared to The production process generates a high activity acidic

Study of the thermoluminescence emission of a natural α-cristobalite

NASA Astrophysics Data System (ADS)

Correcher, V.; Garcia-Guinea, J.; Bustillo, M. A.; Garcia, R.

The thermoluminescence (TL) properties of a well-characterised natural α-cristobalite from Lanzarote (Canary Islands, Spain) have been studied. The natural blue emission (at 400 nm) of this silica polymorph of quartz reveals the appearance of three groups of components peaked at 150, 230-240 and 370 °C, which could be associated, respectively, with (i) structural defects (similar to quartz), (ii) the reversible phase transition from α-cristobalite to β-cristobalite and (iii) electron recombination with unstable holes trapped at oxygen vacancies next to Al ions linked to the formation of β-cristobalite. Similar to quartz, the induced TL (ITL) glow curves display four maxima, peaked at 90, 110, 180 and 220 °C, which could be respectively associated with (i) oxygen vacancies, (ii) recombination of electrons with (H3O4)° centres that can act as hole traps, (iii) [GeO4]- centres that are stabilised with monovalent cations (H+, Li+ or Na+) and (iv) [AlO4]° hole-like centres that are created when alkali ions are moving away from Al sites related probably to the reversible phase transition. The dose dependence of the ITL emission of β-irradiated samples at room temperature exhibits a linear increase in the glow intensity of the 180 °C maximum when increasing the dose (r=0.997) in the range 0.5-10 Gy.

168. ARAIV Index of drawings prepared by Norman Engineering Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

168. ARA-IV Index of drawings prepared by Norman Engineering Company in preparation for construction of ARA-IV. Norman Engineering Company 961-area/ML-1index. Date: March 1961. Ineel index code no. 066-9999-90-613-102731. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

Bioethics in the Laboratory: Synthesis and Interactivity.

ERIC Educational Resources Information Center

Murray, Kevin J.

1999-01-01

Describes the implementation of a bioethics laboratory exercise that incorporates a variety of instructional strategies. In the activity, General Biology students consider relevant and interesting topics of bioethical importance and prepare classroom presentations on the different viewpoints normally attendant to ethical topics. Includes an…

Safety in Academic Chemistry Laboratories. Fourth Edition.

ERIC Educational Resources Information Center

American Chemical Society, Washington, DC.

This booklet provides guidelines for safety in the chemical laboratory. Part I, "Guides for Instructors and Administrators," includes safety rules, safety practices and facilities, preparation for emergencies, safety committees, accident reporting, fire insurance, and listings of some hazardous chemicals. Part II, "Student Guide to…

46 CFR 164.009-21 - Laboratory report.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Description of the specimens tested if the specimens are prepared from composite material. (i) If the test was... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL MATERIALS Noncombustible Materials for Merchant Vessels § 164.009-21 Laboratory...

Guaiacol peroxidase zymography for the undergraduate laboratory.

PubMed

Wilkesman, Jeff; Castro, Diana; Contreras, Lellys M; Kurz, Liliana

2014-01-01

This laboratory exercise presents a novel way to introduce undergraduate students to the specific detection of enzymatic activity by electrophoresis. First, students prepare a crude peroxidase extract and then analyze the homogenate via electrophoresis. Zymography, that is, a SDS-PAGE method to detect enzyme activity, is used to specifically detect peroxidase activity and furthermore, to analyze the total protein profile. After the assay, students may estimate the apparent molecular mass of the enzyme and discuss its structure. After the 4-h experiment, students gain knowledge concerning biological sample preparation, gel preparation, electrophoresis, and the importance of specific staining procedures for the detection of enzymatic activity. Copyright © 2014 The International Union of Biochemistry and Molecular Biology.

Life Sciences Laboratories for the Shuttle/Spacelab

NASA Technical Reports Server (NTRS)

Schulte, L. O.; Kelly, H. B.; Secord, T. C.

1976-01-01

Space Shuttle and Spacelab missions will provide scientists with their first opportunity to participate directly in research in space for all scientific disciplines, particularly the Life Sciences. Preparations are already underway to ensure the success of these missions. The paper summarizes the results of the 1975 NASA-funded Life Sciences Laboratories definition study which defined several long-range life sciences research options and the laboratory designs necessary to accomplish high-priority life sciences research. The implications and impacts of Spacelab design and development on the life sciences missions are discussed. An approach is presented based upon the development of a general-purposs laboratory capability and an inventory of common operational research equipment for conducting life sciences research. Several life sciences laboratories and their capabilities are described to demonstrate the systems potentially available to the experimenter for conducting biological and medical research.

The influence of radiation-induced defects on thermoluminescence and optically stimulated luminescence of α-Al2O3:C

NASA Astrophysics Data System (ADS)

Nyirenda, A. N.; Chithambo, M. L.

2017-04-01

It is known that when α-Al2O3:C is exposed to excessive amounts of ionising radiation, defects are induced within its matrix. We report the influence of radiation-induced defects on the thermoluminescence (TL) and optically stimulated luminescence (OSL) measured from α-Al2O3:C after irradiation to 1000 Gy. These radiation-induced defects are thermally unstable in the region 450-650 °C and result in TL peaks in this range when the TL is measured at 1 °C/s. Heating a sample to 700 °C obliterates the radiation-induced defects, that is, the TL peaks corresponding to the radiation induced defects are no longer observed in the subsequent TL measurements when moderate irradiation doses below 10 Gy are used. The charge traps associated with these radiation-induced defects are more stable than the dosimetric trap when the sample is exposed to either sunlight or 470-nm blue light from LEDs. TL glow curves measured following the defect-inducing irradiation produce a dosimetric peak that is broader and positioned at a higher temperature than observed in glow curves obtained before the heavy irradiation. In addition, sample sensitization/desensitization occurs due to the presence of these radiation-induced defects. Furthermore, both the activation energy and the kinetic order of the dosimetric peak evaluated when the radiation-induced defects are present in the sample are significantly lower in value than those obtained when these defects are absent. The radiation-induced defects also affect the shape and total light sum of the OSL signal as well as the position and width of the resultant residual phototransferred thermoluminescence main peak.

Evaluation of film and thermoluminescent dosimetry of high-energy electron beams in heterogeneous phantoms.

PubMed

el-Khatib, E; Antolak, J; Scrimger, J

1992-01-01

Film and thermoluminescent dosimetry (TLD) are investigated in heterogeneous phantoms irradiated by high-energy electron beams. Both film and TLD are practical dosimeters for multiple and moving beam radiotherapy. The accuracy and precision of these dosimeters for radiation dose measurements in homogeneous water-equivalent phantoms has been discussed in the literature. However, film and TLD are often used for dose measurements in heterogeneous phantoms. In those situations perturbations are produced which are related to the density and atomic number of the phantom material and the physical size and orientation of the dosimeter. In our experiments the relative dose measurements in homogeneous phantoms were the same regardless of dosimeter or dosimeter orientation. However, significant differences were observed between the dose measurements within the inhomogeneity. These differences were influenced by the type and orientation of the dosimeter in addition to the properties of the heterogeneity. These differences could be reproduced with Monte Carlo calculations and modeling of the experimental conditions.

21 CFR 660.52 - Reference preparations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Reference preparations. 660.52 Section 660.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Anti-Human Globulin § 660.52 Reference...

VIEW OF BUILDING 126, LOOKING NORTH. BUILDING 126, THE SOURCE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF BUILDING 126, LOOKING NORTH. BUILDING 126, THE SOURCE CALIBRATION LABORATORY, WAS USED TO EXPOSE AND CALIBRATE RADIATION DETECTION DEVICES, INCLUDING THERMOLUMINESCENT DOSIMETERS, WORN BY EMPLOYEES TO DETECT RADIATION EXPOSURE - Rocky Flats Plant, Source Calibration Laboratory, Between Second & Third Streets & Central & Cedar Avenues, Golden, Jefferson County, CO

Characterisation of the thermally stimulated conductivity and thermoluminescence of natural topaz.

PubMed

Yukihara, E G; McKeever, S W S; Okuno, E; Yoshimura, E M

2002-01-01

Thermally stimulated conductivity (TSC) and thermoluminescence (TL) measurements were conducted to investigate the mechanisms of charge transfer and luminescence emission in natural samples of Brazilian topaz irradiated with beta particles from a 90Sr/90Y source or with a 1.75 MeV Van de Graaff electron beam. The luminescence and conductivity were simultaneously monitored during the heating of the samples, allowing direct comparison of the TL and TSC peaks. The results show that the three main TL peaks are accompanied by corresponding TSC peaks, usually shifted to higher temperatures. Comparison of the relative TL/TSC intensities of peaks 2 and 3 indicates that the process of thermal quenching of the luminescence is probably active, which is also supported by TL/TSC measurements at different heating rates. Results on the dose response of TL/TSC peaks also reveal an interesting feature: the TL intensity shows a monotonic increase with dose in the range of study (50 Gy-3 kGy) comprising a linear-supralinear-saturation characteristic, while the TSC peaks exhibit an increase from 50 Gy to 1 kGy, followed by a small decrease for doses greater than 1 kGy. This result is interpreted in terms of a model involving multiple traps and one recombination centre.

Laboratory Manual (For Concrete Instruction Course); Instructor's Guide, Pilot Program Edition.

ERIC Educational Resources Information Center

Portland Cement Association, Cleveland, OH.

This laboratory manual, prepared for a 2-year program in junior colleges and technical institutes, is designed to accompany the instructional materials to train persons for employment as technicians in the cement and concrete industries. Included are 16 laboratory assignments for each of the following: (1) Principles of Concrete, (2) Concrete in…

Guide for Program Planning: Medical Laboratory Technician.

ERIC Educational Resources Information Center

Kahler, Carol, Ed.; And Others

Prepared by the American Association of Junior Colleges and the National Council on Medical Technology Education, this guide discusses programs for career-entry supportive medical laboratory personnel which have been cooperatively planned by junior college personnel and the medical community, particularly pathologists and medical technologists.…

A comparative study of the thermoluminescent response to beta irradiation of CVD diamond and LiF dosimeters

NASA Astrophysics Data System (ADS)

Bogani, F.; Borchi, E.; Bruzzi, M.; Leroy, C.; Sciortino, S.

1997-02-01

The thermoluminescent (TL) response of Chemical Vapour Deposited (CVD) diamond films to beta irradiation has been investigated. A numerical curve-fitting procedure, calibrated by means of a set of LiF TLD100 experimental spectra, has been developed to deconvolute the complex structured TL glow curves. The values of the activation energy and of the frequency factor related to each of the TL peaks involved have been determined. The TL response of the CVD diamond films to beta irradiation has been compared with the TL response of a set of LiF TLD100 and TLD700 dosimeters. The results have been discussed and compared in view of an assessment of the efficiency of CVD diamond films in future applications as in vivo dosimeters.

Swanson in U.S. Laboratory

NASA Image and Video Library

2014-09-02

ISS040-E-123259 (2 Sept. 2014) --- NASA astronaut Steve Swanson, Expedition 40 commander, prepares to set up the Portable Pulmonary Function System hardware for Sprint VO2max sessions in the Destiny laboratory of the International Space Station. The Sprint experiment measures the effectiveness of high-intensity, low-volume exercise training in minimizing the loss of muscle mass and bone density that occurs during spaceflight.

Laboratory Course on "Streptomyces" Genetics and Secondary Metabolism

ERIC Educational Resources Information Center

Siitonen, Vilja; Räty, Kaj; Metsä-Ketelä, Mikko

2016-01-01

The "'Streptomyces' genetics and secondary metabolism" laboratory course gives an introduction to the versatile soil dwelling Gram-positive bacteria "Streptomyces" and their secondary metabolism. The course combines genetic modification of "Streptomyces"; growing of the strain and protoplast preparation, plasmid…

Biggest-Ever Heat Shield Prepared for Mars Spacecraft

NASA Image and Video Library

2011-05-13

The heat shield for NASA Mars Science Laboratory is the largest ever built for a planetary mission. This image shows the heat shield being prepared at Lockheed Martin Space Systems, Denver, in April 2011.

Standardization of Terminology in Laboratory Medicine II

PubMed Central

Lee, Kap No; Yoon, Jong-Hyun; Min, Won Ki; Lim, Hwan Sub; Song, Junghan; Chae, Seok Lae; Jang, Seongsoo; Ki, Chang-Seok; Bae, Sook Young; Kim, Jang Su; Kwon, Jung-Ah; Lee, Chang Kyu

2008-01-01

Standardization of medical terminology is essential in data transmission between health care institutes and in maximizing the benefits of information technology. The purpose of this study was to standardize medical terms for laboratory observations. During the second year of the study, a standard database of concept names for laboratory terms that covered those used in tertiary health care institutes and reference laboratories was developed. The laboratory terms in the Logical Observation Identifier Names and Codes (LOINC) database were adopted and matched with the electronic data interchange (EDI) codes in Korea. A public hearing and a workshop for clinical pathologists were held to collect the opinions of experts. The Korean standard laboratory terminology database containing six axial concept names, components, property, time aspect, system (specimen), scale type, and method type, was established for 29,340 test observations. Short names and mapping tables for EDI codes and UMLS were added. Synonym tables were prepared to help match concept names to common terms used in the fields. We herein described the Korean standard laboratory terminology database for test names, result description terms, and result units encompassing most of the laboratory tests in Korea. PMID:18756062

The Third International Reference Preparation of Egg Lecithin

PubMed Central

Krag, P.; Bentzon, M. Weis

1961-01-01

The Third International Reference Preparation of Egg Lecithin was produced (in a quantity of 5000 ml) at the WHO Serological Reference Centre, Copenhagen, and assayed in 1958 against the Second International Reference Preparation by four laboratories in three countries. Complement-fixation and slide-flocculation tests were used. The new preparation was found acceptable, and its establishment was authorized by the WHO Expert Committee on Biological Standardization. The average log10 titres and results of analyses of variances are shown. The variances were of the usual order of magnitude, and the differences in titre between antigens containing the Second and the Third International Reference Preparations varied from -0.011 to 0.116; only one of the differences exceeded the 5% limit of significance. The use of the Third International Reference Preparation in tests for the acceptability of lecithin preparations is described. PMID:13753864

Thermoluminescence and the shock and reheating history of meteorites. III - The shergottites

NASA Technical Reports Server (NTRS)

Hasan, F. A.; Haq, M.; Sears, D. W. G.

1986-01-01

Thermoluminescence (TL) measurements on Shergotty, ALHA 77005, Zagami, and EETA 79001 (lithology A) have been used to obtain further information on the shock history of these meteorites. The level of TL sensitivity in the shergottites varied by a factor of 10, but was always low, probably reflecting the amount of crystalline material in the maskelynite. There are trends in the TL peak temperature, peak width, and TL sensitivity which are believed to be associated with different proportions of feldspar in high- and low-temperature forms. This interpretation is consistent with the observed changes induced in the TL properties by annealing shergottites at 400-900 C. It is suggested that the observed trends were produced during postshock crystallization at a variety of cooling rates, the increasing order of cooling rate being EETA 79001, Zagami, ALHA 77005, and Shergotty, and that there is high-temperature feldspar present in all the samples. This implies a postshock temperature above 600 C, and a small (less than 10 m) size of the ejecta. Current theories are well able to explain how objects of this size could have been ejected from Mars.

Automated Microbial Metabolism Laboratory

NASA Technical Reports Server (NTRS)

1973-01-01

Development of the automated microbial metabolism laboratory (AMML) concept is reported. The focus of effort of AMML was on the advanced labeled release experiment. Labeled substrates, inhibitors, and temperatures were investigated to establish a comparative biochemical profile. Profiles at three time intervals on soil and pure cultures of bacteria isolated from soil were prepared to establish a complete library. The development of a strategy for the return of a soil sample from Mars is also reported.

Guaiacol Peroxidase Zymography for the Undergraduate Laboratory

ERIC Educational Resources Information Center

Wilkesman, Jeff; Castro, Diana; Contreras, Lellys M.; Kurz, Liliana

2014-01-01

This laboratory exercise presents a novel way to introduce undergraduate students to the specific detection of enzymatic activity by electrophoresis. First, students prepare a crude peroxidase extract and then analyze the homogenate via electrophoresis. Zymography, that is, a SDS-PAGE method to detect enzyme activity, is used to specifically…

Quality assurance program for molecular medicine laboratories.

PubMed

Hajia, M; Safadel, N; Samiee, S Mirab; Dahim, P; Anjarani, S; Nafisi, N; Sohrabi, A; Rafiee, M; Sabzavi, F; Entekhabi, B

2013-01-01

Molecular diagnostic methods have played and continuing to have a critical role in clinical laboratories in recent years. Therefore, standardization is an evolutionary process that needs to be upgrade with increasing scientific knowledge, improvement of the instruments and techniques. The aim of this study was to design a quality assurance program in order to have similar conditions for all medical laboratories engaging with molecular tests. We had to design a plan for all four elements; required space conditions, equipments, training, and basic guidelines. Necessary guidelines was prepared and confirmed by the launched specific committee at the Health Reference Laboratory. Several workshops were also held for medical laboratories directors and staffs, quality control manager of molecular companies, directors and nominees from universities. Accreditation of equipments and molecular material was followed parallel with rest of program. Now we are going to accredit medical laboratories and to evaluate the success of the program. Accreditation of medical laboratory will be succeeding if its basic elements are provided in advance. Professional practice guidelines, holding training and performing accreditation the molecular materials and equipments ensured us that laboratories are aware of best practices, proper interpretation, limitations of techniques, and technical issues. Now, active external auditing can improve the applied laboratory conditions toward the defined standard level.

A Phase Transfer Catalyzed Permanganate Oxidation: Preparation of Vanillin from Isoeugenol Acetate.

ERIC Educational Resources Information Center

Lampman, Gary M.; Sharpe, Steven D.

1983-01-01

Background information, laboratory procedures, and results are provided for the preparation of vanillin from isoeugenol acetate. Reaction scheme used to prepare the vanillin and a table indicating the different oxidation experiments carried out on isoeugenol or isoeugenol acetate are also provided. (JN)

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; preparation procedure for aquatic biological material determined for trace metals

USGS Publications Warehouse

Hoffman, Gerald L.

1996-01-01

A method for the chemical preparation of tissue samples that are subsequently analyzed for 22 trace metals is described. The tissue-preparation procedure was tested with three National Institute of Standards and Technology biological standard reference materials and two National Water Quality Laboratory homogenized biological materials. A low-temperature (85 degrees Celsius) nitric acid digestion followed by the careful addition of hydrogen peroxide (30-percent solution) is used to decompose the biological material. The solutions are evaporated to incipient dryness, reconstituted with 5 percent nitric acid, and filtered. After filtration the solutions were diluted to a known volume and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and cold vapor-atomic absorption spectrophotometry (CV-AAS). Many of the metals were determined by both ICP-MS and ICP-AES. This report does not provide a detailed description of the instrumental procedures and conditions used with the three types of instrumentation for the quantitation of trace metals determined in this study. Statistical data regarding recovery, accuracy, and precision for individual trace metals determined in the biological material tested are summarized.

Making Sparklers: An Introductory Laboratory Experiment

NASA Astrophysics Data System (ADS)

Keeney, Allen; Walters, Christina; Cornelius, Richard D.

1995-07-01

A laboratory experiment consisting of the preparation of sparklers has been developed as part of a project which organizes the general chemistry sequence according to subjects with which students are familiar. This laboratory makes use of oxidation/reduction chemistry to produce a product familiar to students. The result is a mixture rather than a compound, but the composition must be carefully measured to produce a sparkler that will stay lit and produce sparks. The dramatic reaction may be the most impressive and memorable experience that students encounter in the laboratory. Sparklers are formulated from iron, magnesium, and aluminum powders, plus potassium chlorate and barium nitrate held on thick iron wire by a starch paste. At elevated temperatures metal nitrates and chlorates decompose to produces gases, providing the necessary force to eject bits of powdered, burning metal into the air.

Annual Report on the State of the DOE National Laboratories

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

None

2017-01-01

This first Annual Report to Congress on the State of the DOE National Laboratories provides a comprehensive overview of the Lab system, covering S&T programs, management and strategic planning. The Department committed to prepare this report in response to recommendations from the Congressionally mandated Commission to Review the Effectiveness of the National Energy Laboratories (CRENEL) that the Department should better communicate the value that the Laboratories provide to the Nation. We expect that future annual reports will be much more compact, building on the extensive description of the Laboratories and of the governance structures that are part of this firstmore » report.« less

Space Radiation Effects Laboratory

NASA Technical Reports Server (NTRS)

1969-01-01

The SREL User's Handbook is designed to provide information needed by those who plan experiments involving the accelerators at this laboratory. Thus the Handbook will contain information on the properties of the machines, the beam parameters, the facilities and services provided for experimenters, etc. This information will be brought up to date as new equipment is added and modifications accomplished. This Handbook is influenced by the many excellent models prepared at other accelerator laboratories. In particular, the CERN Synchrocyclotron User's Handbook (November 1967) is closely followed in some sections, since the SREL Synchrocyclotron is a duplicate of the CERN machine. We wish to thank Dr. E. G. Michaelis for permission to draw so heavily on his work, particularly in Section II of this Handbook. We hope that the Handbook will prove useful, and will welcome suggestions and criticism.

Real-time laboratory exercises to test contingency plans for classical swine fever: experiences from two national laboratories.

PubMed

Koenen, F; Uttenthal, A; Meindl-Böhmer, A

2007-12-01

In order to adequately and efficiently handle outbreaks of contagious diseases such as classical swine fever (CSF), foot and mouth disease or highly pathogenic avian influenza, competent authorities and the laboratories involved have to be well prepared and must be in possession of functioning contingency plans. These plans should ensure that in the event of an outbreak access to facilities, equipment, resources, trained personnel, and all other facilities needed for the rapid and efficient eradication of the outbreak is guaranteed, and that the procedures to follow are well rehearsed. It is essential that these plans are established during 'peace-time' and are reviewed regularly. This paper provides suggestions on how to perform laboratory exercises to test preparedness and describes the experiences of two national reference laboratories for CSF. The major lesson learnt was the importance of a well-documented laboratory contingency plan. The major pitfalls encountered were shortage of space, difficulties in guaranteeing biosecurity and sufficient supplies of sterile equipment and consumables. The need for a standardised laboratory information management system, that is used by all those involved in order to reduce the administrative load, is also discussed.

Percentage depth dose evaluation in heterogeneous media using thermoluminescent dosimetry

PubMed Central

da Rosa, L.A.R.; Campos, L.T.; Alves, V.G.L.; Batista, D.V.S.; Facure, A.

2010-01-01

The purpose of this study is to investigate the influence of lung heterogeneity inside a soft tissue phantom on percentage depth dose (PDD). PDD curves were obtained experimentally using LiF:Mg,Ti (TLD‐100) thermoluminescent detectors and applying Eclipse treatment planning system algorithms Batho, modified Batho (M‐Batho or BMod), equivalent TAR (E‐TAR or EQTAR), and anisotropic analytical algorithm (AAA) for a 15 MV photon beam and field sizes of 1×1,2×2,5×5, and 10×10cm2. Monte Carlo simulations were performed using the DOSRZnrc user code of EGSnrc. The experimental results agree with Monte Carlo simulations for all irradiation field sizes. Comparisons with Monte Carlo calculations show that the AAA algorithm provides the best simulations of PDD curves for all field sizes investigated. However, even this algorithm cannot accurately predict PDD values in the lung for field sizes of 1×1 and 2×2cm2. An overdosage in the lung of about 40% and 20% is calculated by the AAA algorithm close to the interface soft tissue/lung for 1×1 and 2×2cm2 field sizes, respectively. It was demonstrated that differences of 100% between Monte Carlo results and the algorithms Batho, modified Batho, and equivalent TAR responses may exist inside the lung region for the 1×1cm2 field. PACS number: 87.55.kd

Biosafety Practices and Emergency Response at the Idaho National Laboratory and Los Alamos National Laboratory

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

Frank F. Roberto; Dina M. Matz

2008-03-01

Strict federal regulations govern the possession, use, and transfer of pathogens and toxins with potential to cause harm to the public, either through accidental or deliberate means. Laboratories registered through either the Centers for Disease Control and Prevention (CDC), the U.S. Dept. of Agriculture (USDA), or both, must prepare biosafety, security, and incident response plans, conduct drills or exercises on an annual basis, and update plans accordingly. At the Idaho National Laboratory (INL), biosafety, laboratory, and emergency management staff have been working together for 2 years to satisfy federal and DOE/NNSA requirements. This has been done through the establishment ofmore » plans, training, tabletop and walk-through exercises and drills, and coordination with local and regional emergency response personnel. Responding to the release of infectious agents or toxins is challenging, but through familiarization with the nature of the hazardous biological substances or organisms, and integration with laboratory-wide emergency response procedures, credible scenarios are being used to evaluate our ability to protect workers, the public, and the environment from agents we must work with to provide for national biodefense.« less

Synthesis of Mg{sub 2}SiO{sub 4}:Dy{sup 3+} nanoparticles by hydrothermal method and investigation of their thermo and photo luminescence properties

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

Ghahari, M., E-mail: maghahari@icrc.ac.ir; Mostafavi, K.

2016-05-15

Highlights: • Mg{sub 2}SiO{sub 4}:Dy{sup 3+} nanoparticles have been prepared by hydrothermal and combustion methods. • Thermo and photo luminescent behavior of Mg{sub 2}SiO{sub 4}:Dy{sup 3+} was studied. • The effect of synthesis method on TL properties of Mg{sub 2}SiO{sub 4}:Dy{sup 3+} was investigated. • The optimal dopant concentration for thermo-luminescent property was obtained. - Abstract: In this study, photo and thermo-luminescent properties of Nano crystalline Mg{sub 2}SiO{sub 4}:Dy{sup 3+} prepared by a hydrothermal method were studied and compared to those of nanoparticles prepared by combustion method. The synthesized sample was characterized by X-ray diffraction, transmission electron microscopy, scanning electronmore » microscopy and photoluminescence spectroscopy. The effect of Dy concentration on photo and thermoluminescent intensities was studied. The X-ray diffraction (XRD) patterns of the samples revealed that forsterite was formed as a major phase for all the samples. The crystallite size was found to be in the range of 20–50 nm. The thermo luminescent glow curve indicated that the hydrothermal sample was more efficient than the combustion sample. Two prominent TL bands located at 200 nm and 320 nm were recorded. The prepared nanoparticles exhibited a roughly linear dose response to absorbed dose of 1000 Gy received from 60Co gamma source, suggesting that nanomaterial could be a good candidate for high dose dosimetry.« less

CTBTO Contractor Laboratory Test Sample Production Report

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

Bob Hague; Tracy Houghton; Nick Mann

2013-08-01

In October 2012 scientists from both Idaho National Laboratory (INL) and the CTBTO contact laboratory at Seibersdorf, Austria designed a system and capability test to determine if the INL could produce and deliver a short lived radio xenon standard in time for the standard to be measured at the CTBTO contact laboratory at Seibersdorf, Austria. The test included sample standard transportation duration and potential country entrance delays at customs. On October 23, 2012 scientists at the Idaho National Laboratory (INL) prepared and shipped a Seibersdorf contract laboratory supplied cylinder. The canister contained 1.0 scc of gas that consisted of 70%more » xenon and 30% nitrogen by volume. The t0 was October 24, 2012, 1200 ZULU. The xenon content was 0.70 +/ 0.01 scc at 0 degrees C. The 133mXe content was 4200 +/ 155 dpm per scc of stable xenon on t0 (1 sigma uncertainty). The 133Xe content was 19000 +/ 800 dpm per scc of stable xenon on t0 (1 sigma uncertainty).« less

Formulation, Preparation, and Characterization of Polyurethane Foams

ERIC Educational Resources Information Center

Pinto, Moises L.

2010-01-01

Preparation of laboratory-scale polyurethane foams is described with formulations that are easy to implement in experiments for undergraduate students. Particular attention is given to formulation aspects that are based on the main chemical reactions occurring in polyurethane production. This allows students to develop alternative formulations to…

Purdue Rare Isotope Measurement Laboratory

NASA Astrophysics Data System (ADS)

Caffee, M.; Elmore, D.; Granger, D.; Muzikar, P.

2002-12-01

The Purdue Rare Isotope Measurement Laboratory (PRIME Lab) is a dedicated research and service facility for accelerator mass spectrometry. AMS is an ultra-sensitive analytical technique used to measure low levels of long-lived cosmic-ray-produced and anthropogenic radionuclides, and rare trace elements. We measure 10Be (T1/2 = 1.5 My), 26Al (.702 My), 36Cl (.301 My), and 129I (16 My), in geologic samples. Applications include dating the cosmic-ray-exposure time of rocks on Earth's surface, determining rock and sediment burial ages, measuring the erosion rates of rocks and soils, and tracing and dating ground water. We perform sample preparation and separation chemistries for these radio-nuclides for our internal research activities and for those external researchers not possessing this capability. Our chemical preparation laboratories also serve as training sites for members of the geoscience community developing these techniques at their institutions. Research at Purdue involves collaborators among members of the Purdue Departments of Physics, Earth and Atmospheric Sciences, Chemistry, Agronomy, and Anthropology. We also collaborate and serve numerous scientists from other institutions. We are currently in the process of modernizing the facility with the goals of higher precision for routinely measured radio-nuclides, increased sample throughput, and the development of new measurement capabilities for the geoscience community.

Safety in the Science Laboratory, A Guide.

ERIC Educational Resources Information Center

Christian, Floyd T.

The bulletin was prepared as a general guide to encourage the use of safe practices in science laboratories in Florida schools. The guide begins with an outline of recommended emergency procedures. Chapter I discusses the importance of safety in the science program. Chapter II discusses handling and storage of equipment, and designing laboratory…

Pre-Service Chemistry Teachers' Competencies in the Laboratory: A Cross-Grade Study in Solution Preparation

ERIC Educational Resources Information Center

Karatas, F. O.

2016-01-01

One of the prerequisites for chemistry teacher candidates is to demonstrate certain laboratory skills. This article aims to determine and discuss the competencies of pre-service chemistry teachers in a chemistry laboratory context working with solution chemistry content. The participants in this study consisted of a group of pre-service chemistry…

The dosimetric properties of phosphate glass systems prepared by different chemical nanomaterials.

PubMed

Abdelhalim, Mohamed Anwar K; Al-Shamrani, Bandar Mora

2016-12-01

The synthesis and characterization of glass systems were carried out using prepared nanocrystals injected into a glass matrix as a thermoluminescence (TL) activator using the melt-quenching method. Sample 1 was prepared as [40P 2 O 5 50BaO:2.5MgO, 2.5Na 2 O, 5TiO 2 ], sample 2 as [37.5P 2 O 5 37.5CaO:25TiO 2 ] and sample 3 as [50P 2 O 5 -50Li 2 O]. Formation of the synthesized compound was confirmed by studying the X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM) images. An annealing procedure was carried out for 1 h at 400 °C. The glow curve position and shape shifted dramatically and linearly to the higher temperature values on increasing the heating rate. A heating rate of 30 °C/s was the most suitable for obtaining a high TL response. Samples 2 and 3 have the highest TL response, which approached the effective atomic number (Z eff ) of natural bone. The observed TL sensitivity of the prepared samples 2 and 3 is less than that of commercially available 'TLD-200 chips' and LiF:Mg,Ti (TLD-100) phosphor. Sample [37.5P 2 O 5 37.5CaO:25TiO 2 ] would be useful in personal and environmental dosimetry for measuring high doses of gamma radiation. Sample [50P 2 O 5 -50Li 2 O] is a good dosimeter, although it requires the addition of an appropriate transitional metal (activator) to overcome the problem of high fading. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Immunomodulative properties of humic peat preparations

NASA Astrophysics Data System (ADS)

Stepchenko, L. M.; Syedykh, N. J.

2010-05-01

It is proved, that the humic peat preparations promote the resistance of plants, animals and poultry to the influence of both abyotyc and byotyc extreme factors of external environment, to action. It was shown by us before, that biologically active compounds from peat promote stability against different diseases of agricultural animals and poultry. We conducted researches of humic preparations influence (hydrohumate and oxyhumate) on several indexes of immunoreactivity of the organisms of chickens broilers, ostriches, cows and laboratory rats. It is found out, that adding of humic preparations to forage or drinking water results in the normalization of immunity indexes; in particular, leucocytes level, in the increase of the level of some classes of immunoglobuline in blood, of haemoglobin level, T- and B-lymphocytes level, as well as common unspecific resistance - lyzocymic, phagocytic and bactericidic activity. These results allow to suggest that the peat humic preparations show immunomodulative activity, influencing both on humoral and cel immunity links.

Intensity variation study of the radiation field in a mammographic system using thermoluminescent dosimeters TLD-900 (CaSO4:Dy)

NASA Astrophysics Data System (ADS)

Corrêa, E. L.; Silva, J. O.; Vivolo, V.; Potiens, M. P. A.; Daros, K. A. C.; Medeiros, R. B.

2014-02-01

This study presents the results of the intensity variation of the radiation field in a mammographic system using the thermoluminescent dosimeter TLD-900 (CaSO4:Dy). These TLDs were calibrated and characterized in an industrial X-ray system used for instruments calibration, in the energy range used in mammography. They were distributed in a matrix of 19 lines and five columns, covering an area of 18 cm×8 cm in the center of the radiation field on the clinical equipment. The results showed a variation of the intensity probably explained by the non-uniformity of the field due to the heel effect.

A Laboratory Preparation of Aspartame Analogs Using Simultaneous Multiple Parallel Synthesis Methodology

ERIC Educational Resources Information Center

Qvit, Nir; Barda, Yaniv; Gilon, Chaim; Shalev, Deborah E.

2007-01-01

This laboratory experiment provides a unique opportunity for students to synthesize three analogues of aspartame, a commonly used artificial sweetener. The students are introduced to the powerful and useful method of parallel synthesis while synthesizing three dipeptides in parallel using solid-phase peptide synthesis (SPPS) and simultaneous…

Preparation and validation of gross alpha/beta samples used in EML`s quality assessment program

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

Scarpitta, S.C.

1997-10-01

A set of water and filter samples have been incorporated into the existing Environmental Measurements Laboratory`s (EML) Quality Assessment Program (QAP) for gross alpha/beta determinations by participating DOE laboratories. The participating laboratories are evaluated by comparing their results with the EML value. The preferred EML method for measuring water and filter samples, described in this report, uses gas flow proportional counters with 2 in. detectors. Procedures for sample preparation, quality control and instrument calibration are presented. Liquid scintillation (LS) counting is an alternative technique that is suitable for quantifying both the alpha ({sup 241}Am, {sup 230}Th and {sup 238}Pu) andmore » beta ({sup 90}Sr/{sup 90}Y) activity concentrations in the solutions used to prepare the QAP water and air filter samples. Three LS counting techniques (Cerenkov, dual dpm and full spectrum analysis) are compared. These techniques may be used to validate the activity concentrations of each component in the alpha/beta solution before the QAP samples are actually prepared.« less

Quality Assurance Program for Molecular Medicine Laboratories

PubMed Central

Hajia, M; Safadel, N; Samiee, S Mirab; Dahim, P; Anjarani, S; Nafisi, N; Sohrabi, A; Rafiee, M; Sabzavi, F; Entekhabi, B

2013-01-01

Background: Molecular diagnostic methods have played and continuing to have a critical role in clinical laboratories in recent years. Therefore, standardization is an evolutionary process that needs to be upgrade with increasing scientific knowledge, improvement of the instruments and techniques. The aim of this study was to design a quality assurance program in order to have similar conditions for all medical laboratories engaging with molecular tests. Methods: We had to design a plan for all four elements; required space conditions, equipments, training, and basic guidelines. Necessary guidelines was prepared and confirmed by the launched specific committee at the Health Reference Laboratory. Results: Several workshops were also held for medical laboratories directors and staffs, quality control manager of molecular companies, directors and nominees from universities. Accreditation of equipments and molecular material was followed parallel with rest of program. Now we are going to accredit medical laboratories and to evaluate the success of the program. Conclusion: Accreditation of medical laboratory will be succeeding if its basic elements are provided in advance. Professional practice guidelines, holding training and performing accreditation the molecular materials and equipments ensured us that laboratories are aware of best practices, proper interpretation, limitations of techniques, and technical issues. Now, active external auditing can improve the applied laboratory conditions toward the defined standard level. PMID:23865028

[Laboratory medicine in the obligatory postgraduate clinical training system--common clinical training program in the department of laboratory medicine in our prefectural medical university hospital].

PubMed

Okamoto, Yasuyuki

2003-04-01

I propose a postgraduate common clinical training program to be provided by the department of laboratory medicine in our prefectural medical university hospital. The program has three purposes: first, mastering basic laboratory tests; second, developing the skills necessary to accurately interpret laboratory data; third, learning specific techniques in the field of laboratory medicine. For the first purpose, it is important that medical trainees perform testing of their own patients at bedside or in the central clinical laboratory. When testing at the central clinical laboratory, instruction by expert laboratory technicians is helpful. The teaching doctors in the department of laboratory medicine are asked to advise the trainees on the interpretation of data. Consultation will be received via interview or e-mail. In addition, the trainees can participate in various conferences, seminars, and meetings held at the central clinical laboratory. Finally, in order to learn specific techniques in the field of laboratory medicine, several special courses lasting a few months will be prepared. I think this program should be closely linked to the training program in internal medicine.

A comparison of results from two mycology laboratories for the diagnosis of onychomycosis: a study of 85 cases in a geriatric population.

PubMed

Scherer, William P; Scherer, Michael D

2004-01-01

An investigative study was performed to compare the results from two mycology laboratories for the diagnosis of onychomycosis in a geriatric population and to determine the possible pharmacologic treatments based on the two laboratories' results. In this study, 85 cases of suspected onychomycosis involving men and women 65 years and older from a nursing home setting in South Florida were used. Samples were taken from the hallux toenail and sent to two different mycology laboratories for fluorescent potassium hydroxide preparation and microscopic examination of a fungal culture. Of the 85 cases studied, the two mycology laboratories reported similar potassium hydroxide preparation results for 58.8% of the patients and similar fungal culture results for genus and species identification for 37.6% of the patients. When the potassium hydroxide preparation and fungal culture results were combined, the two mycology laboratories reported similar results for only 27.1% of the patients. As a result of the two mycology laboratories' findings, the possible US Food and Drug Administration-approved pharmacologic treatments may differ for 43.5% of the patients studied. The discrepancy between the two independent laboratories leaves physicians to question the reproducibility of fluorescent potassium hydroxide preparation and fungal culture analysis in a geriatric patient population for the diagnosis of onychomycosis.

Author Contribution to the Pu Handbook II: Chapter 37 LLNL Integrated Sample Preparation Glovebox (TEM) Section

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

Wall, Mark A.

The development of our Integrated Actinide Sample Preparation Laboratory (IASPL) commenced in 1998 driven by the need to perform transmission electron microscopy studies on naturally aged plutonium and its alloys looking for the microstructural effects of the radiological decay process (1). Remodeling and construction of a laboratory within the Chemistry and Materials Science Directorate facilities at LLNL was required to turn a standard radiological laboratory into a Radiological Materials Area (RMA) and Radiological Buffer Area (RBA) containing type I, II and III workplaces. Two inert atmosphere dry-train glove boxes with antechambers and entry/exit fumehoods (Figure 1), having a baseline atmospheremore » of 1 ppm oxygen and 1 ppm water vapor, a utility fumehood and a portable, and a third double-walled enclosure have been installed and commissioned. These capabilities, along with highly trained technical staff, facilitate the safe operation of sample preparation processes and instrumentation, and sample handling while minimizing oxidation or corrosion of the plutonium. In addition, we are currently developing the capability to safely transfer small metallographically prepared samples to a mini-SEM for microstructural imaging and chemical analysis. The gloveboxes continue to be the most crucial element of the laboratory allowing nearly oxide-free sample preparation for a wide variety of LLNL-based characterization experiments, which includes transmission electron microscopy, electron energy loss spectroscopy, optical microscopy, electrical resistivity, ion implantation, X-ray diffraction and absorption, magnetometry, metrological surface measurements, high-pressure diamond anvil cell equation-of-state, phonon dispersion measurements, X-ray absorption and emission spectroscopy, and differential scanning calorimetry. The sample preparation and materials processing capabilities in the IASPL have also facilitated experimentation at world-class facilities such as

Slice&Dice: Recognizing Food Preparation Activities Using Embedded Accelerometers

NASA Astrophysics Data System (ADS)

Pham, Cuong; Olivier, Patrick

Within the context of an endeavor to provide situated support for people with cognitive impairments in the kitchen, we developed and evaluated classifiers for recognizing 11 actions involved in food preparation. Data was collected from 20 lay subjects using four specially designed kitchen utensils incorporating embedded 3-axis accelerometers. Subjects were asked to prepare a mixed salad in our laboratory-based instrumented kitchen environment. Video of each subject's food preparation activities were independently annotated by three different coders. Several classifiers were trained and tested using these features. With an overall accuracy of 82.9% our investigation demonstrated that a broad set of food preparation actions can be reliably recognized using sensors embedded in kitchen utensils.

Development of a Hampton University Program for Novel Breast Cancer Imaging and Therapy Research

DTIC Science & Technology

2013-04-01

intracavitary brachytherapy procedures during laboratory pre-clinical imaging and dosimetry equipment testing, calibration and data processing, in collaboration... electronics and detector instrumentation development; 4) breast phantom construction and implantation; 5) laboratory pre-clinical device testing...such as the ionization chamber, diode, radiographic verification 6 films and thermoluminescent dosimeters ( TLD ) but the scintillator fiber detectors

Photoluminescence, optically stimulated luminescence, and thermoluminescence study of RbMgF3:Eu2+

NASA Astrophysics Data System (ADS)

Dotzler, C.; Williams, G. V. M.; Rieser, U.; Robinson, J.

2009-01-01

Optically stimulated luminescence (OSL) and thermoluminescence are observed in polycrystalline RbMgF3:Eu2+ after x-ray, γ-ray, or β irradiation. The main electron traps are F-centers but there are other unidentified traps. The main hole traps at room temperature are probably Eu3+ and thermal or optical stimulation leads to electron-hole recombination at the Eu3+ site and Eu2+ emissions arising from P6J to S87/2 and 4f5d(Eg) to S87/2 transitions. We find that some of the electron traps can be emptied by infrared stimulation and all of the electron traps can be emptied by white light stimulation. The OSL dark decay is long and exceeds 5 days for traps that are emptied by white light stimulation after initial infrared bleaching. Our results show that this compound can be used as a radiation dosimeter for intermediate dose levels where the R87b self-dose does not significantly affect the dose reading.

Bioterrorism and the Role of the Clinical Microbiology Laboratory

PubMed Central

2015-01-01

SUMMARY Regular review of the management of bioterrorism is essential for maintaining readiness for these sporadically occurring events. This review provides an overview of the history of biological disasters and bioterrorism. I also discuss the recent recategorization of tier 1 agents by the U.S. Department of Health and Human Services, the Laboratory Response Network (LRN), and specific training and readiness processes and programs, such as the College of American Pathologists (CAP) Laboratory Preparedness Exercise (LPX). LPX examined the management of cultivable bacterial vaccine and attenuated strains of tier 1 agents or close mimics. In the LPX program, participating laboratories showed improvement in the level of diagnosis required and referral of isolates to an appropriate reference laboratory. Agents which proved difficult to manage in sentinel laboratories included the more fastidious Gram-negative organisms, especially Francisella tularensis and Burkholderia spp. The recent Ebola hemorrhagic fever epidemic provided a check on LRN safety processes. Specific guidelines and recommendations for laboratory safety and risk assessment in the clinical microbiology are explored so that sentinel laboratories can better prepare for the next biological disaster. PMID:26656673

Strategies for laboratory cost containment and for pathologist shortage: centralised pathology laboratories with microwave-stimulated histoprocessing and telepathology.

PubMed

Leong, Anthony S Y; Leong, F Joel W M

2005-02-01

The imposition of laboratory cost containment, often from external forces, dictates the necessity to develop strategies to meet laboratory cost savings. In addition, the national and worldwide shortage of anatomical pathologists makes it imperative to examine our current practice and laboratory set-ups. Some of the strategies employed in other areas of pathology and laboratory medicine include improvements in staff productivity and the adoption of technological developments that reduce manual intervention. However, such opportunities in anatomical pathology are few and far between. Centralisation has been an effective approach in bringing economies of scale, the adoption of 'best practices' and the consolidation of pathologists, but this has not been possible in anatomical pathology because conventional histoprocessing takes a minimum of 14 hours and clinical turnaround time requirements necessitate that the laboratory and pathologist be in proximity and on site. While centralisation of laboratories for clinical chemistry, haematology and even microbiology has been successful in Australia and other countries, the essential requirements for anatomical pathology laboratories are different. In addition to efficient synchronised courier networks, a method of ultra-rapid tissue processing and some expedient system of returning the prepared tissue sections to the remote laboratory are essential to maintain the turnaround times mandatory for optimal clinical management. The advent of microwave-stimulated tissue processing that can be completed in 30-60 minutes and the immediate availability of compressed digital images of entire tissue sections via telepathology completes the final components of the equation necessary for making centralised anatomical pathology laboratories a reality.

The planning and establishment of a sample preparation laboratory for drug discovery

PubMed Central

Dufresne, Claude

2000-01-01

Nature has always been a productive source of new drugs. With the advent of high-throughput screening, it has now become possible to rapidly screen large sample collections. In addition to seeking greater diversity from natural product sources (micro-organisms, plants, etc.), fractionation of the crude extracts prior to screening is becoming a more important part of our efforts. As sample preparation protocols become more involved, automation can help to achieve and maintain a desired sample throughput. To address the needs of our screening program, two robotic systems were designed. The first system processes crude extracts all the way to 96-well plates, containing solutions suitable for screening in biological and biochemical assays. The system can dissolve crude extracts, fractionate them on solid-phase extraction cartridges, dry and weigh each fraction, re-dissolve them to a known concentration, and prepare mother plates. The second system replicates mother plates into a number of daughter plates. PMID:18924691

Prepare, Do, Review: A skills-based approach for laboratory practical classes in biochemistry and molecular biology.

PubMed

Arthur, Peter; Ludwig, Martha; Castelli, Joane; Kirkwood, Paul; Attwood, Paul

2016-05-06

A new laboratory practical system is described which is comprised of a number of laboratory practical modules, each based around a particular technique or set of techniques, related to the theory part of the course but not designed to be dependent on it. Each module comprises an online recorded pre-lab lecture, the laboratory practical itself and a post-lab session in which students make oral presentations on different aspects of the practical. Each part of the module is assessed with the aim of providing rapid feedback to staff and students. Each laboratory practical is the responsibility of a single staff member and through this "ownership," continual review and updating is promoted. Examples of changes made by staff to modules as a result of student feedback are detailed. A survey of students who had experienced both the old-style laboratory course and the new one provided evidence of increased satisfaction with the new program. The assessment of acquired shills in the new program showed that it was much more effective than the old course. © 2016 by The International Union of Biochemistry and Molecular Biology, 44:276-287, 2016. © 2016 The International Union of Biochemistry and Molecular Biology.

Naval Research Laboratory Arctic Initiatives

DTIC Science & Technology

2011-06-01

Campaign Code 7420 Arctic Modeling Code 7320/7500/7600 In-situ NRL, CRREL NRL boreholes Strategy Remote Sensing Synergism −Collect in-situ...Navy and Marine Corps Corporate Laboratory An array of BMFCs being prepared for deployment. Each BMFC consists of a weighted anode laid flat onto...Gas CH4 E C D CO2 BGHS Free Methane Gas Hydrates HCO3- HCO3- Seismic and geochemical data to predict deep sediment hydrates Estimate spatial

[Status of the clinical laboratory in the mandatory postgraduate medical training system. (1) Report from a laboratory technologist].

PubMed

Nishikawa, Yoko

2006-06-01

According to a new system for postgraduate clinical training, 33 medical trainees have been accepted for the past two years at Osaka General Medical Center. Before practicing clinical medicine in each division by a super-rotated table, orientation is scheduled for 5 days to master the basic systems indispensable to the hospital. In this orientation, training in laboratory medicine is performed for 7 hours (3.5 hours for 2 days). Trainees are divided into 4 groups and learn emergency tests of chemistry, hematology and urinalysis, blood transfusion, physiology and microbiology for 60 min each. Laboratory technologists instruct the trainees to gain the basic skills. The main contents are blood gas measuring in chemistry, sample preparation in hematology and urinalysis, taking each other's ECG, ordering blood products for transfusion, serologic study of infectious diseases, and Gram stain in microbiology. Although it is difficult to find time for routine analysis and instructing trainees in the clinical laboratory, it is a suitable opportunity for revision, also for laboratory technologists, and for communication to discuss clinical matters.

Photoluminescence and thermoluminescence of K2 Mg(SO4 )2 :Eu and evaluation of its kinetic parameters.

PubMed

Deshpande, Archana; Dhoble, N S; Gedam, S C; Dhoble, S J

2017-08-01

The K 2 Mg(SO 4 ) 2 :Eu phosphor, synthesized by a solid-state diffusion method, was studied for its photoluminescence (PL) and thermoluminescence (TL) characteristics. The X-ray diffraction (XRD) pattern of the material was matched with the standard JCPDF No. 36-1499. For PL characteristics, K 2 Mg(SO 4 ) 2 :Eu 2 + showed an emission peak at 474 nm when excited at 340 nm, while it showed Eu 3 + emission at 580 nm, and 594 nm splitting at 613 nm and 618 nm for an excitation of 396 nm wavelength due to radiative transitions from 5 D 0 to 7 F j (j = 0, 1, 2, 3). The Commission International de I' Eclairage (CIE) chromaticity coordinates were also calculated for the K 2 Mg(SO 4 ) 2 :Eu phosphor, and were close to the NTSC standard values. For the TL study, the prepared sample was irradiated using a 60 Co source of γ-irradiation at the dose rate of 0.322 kGy/h for 2 min. The formation of traps in K 2 Mg (SO 4 ) 2 :Eu and the effects of γ-radiation dose on the glow curve are discussed. Well defined broad glow peaks were obtained at 186°C. With increasing γ-ray dose, the sample showed linearity in intensity. The presence of a single glow peak indicated that there was only one set of traps being activated within the particular temperature range. The presented phosphors were also studied for their fading, reusability and trapping parameters. There was just 2% fading during a period of 30 days, indicating no serious fading problem. Kinetic parameters were calculated using the initial rise method and Chen's half-width method. Activation energy and frequency factor were found to be 0.77 eV and 1.41 × 10 6  sec -1 . Copyright © 2016 John Wiley & Sons, Ltd.

The laboratory astrophysics facility at University College

NASA Astrophysics Data System (ADS)

Hyland, A. R.; Smith, R. G.; Robinson, G.

A laboratory astrophysics facility for the study of the terrestrial analogues of interstellar dust grains is being developed in the Physics Department, University College, Australian Defence Force Academy. The facility consists of a gas handling system for the preparation of samples, a closed-cycle cooler and specimen chamber, and a Fourier Transform Infrared (FTIR) Spectrometer capable of high resolution (0.3/cm) and high sensitivity measurements, currently from 1-25 microns. The layout and construction of the laboratory are described, and the proposed initial experimental program aimed at determining the optical constants of ices, over a wide wavelength range for comparison with astronomical observations, is discussed.

Luminescence studies of rare earth doped yttrium gadolinium mixed oxide phosphor

NASA Astrophysics Data System (ADS)

Som, S.; Choubey, A.; Sharma, S. K.

2012-09-01

This paper reports the photoluminescence and thermoluminescence properties of gamma ray induced rare earth doped yttrium gadolinium mixed oxide phosphor. The europium (Eu3+) was used as rare earth dopant. The phosphor was prepared by chemical co-precipitation method according to the formula (Y2-x-yGdx) O3: Euy3+ (x=0.5; y=0.05). The photoluminescence emission spectrum of the prepared phosphor shows intense peaks in the red region at 615 nm for 5D0→7F2 transitions and the photoluminescence excitation spectra show a broad band located around 220-270 nm for the emission wavelength fixed at 615 nm. The thermoluminescence studies were carried out after irradiating the phosphor by gamma rays in the dose range from 100 Gy to 1 KGy. In the thermoluminescence glow curves, one single peak was observed at about 300 °C of which the intensity increases linearly in the studied dose range of gamma rays. The glow peak was deconvoluted by GlowFit program and the kinetic parameters associated with the deconvoluted peaks were calculated. The kinetic parameters were also calculated by various glow curve shape and heating rate methods.

128 slice computed tomography dose profile measurement using thermoluminescent dosimeter

NASA Astrophysics Data System (ADS)

Salehhon, N.; Hashim, S.; Karim, M. K. A.; Ang, W. C.; Musa, Y.; Bahruddin, N. A.

2017-05-01

The increasing use of computed tomography (CT) in clinical practice marks the needs to understand the dose descriptor and dose profile. The purposes of the current study were to determine the CT dose index free-in-air (CTDIair) in 128 slice CT scanner and to evaluate the single scan dose profile (SSDP). Thermoluminescent dosimeters (TLD-100) were used to measure the dose profile of the scanner. There were three sets of CT protocols where the tube potential (kV) setting was manipulated for each protocol while the rest of parameters were kept constant. These protocols were based from routine CT abdominal examinations for male adult abdomen. It was found that the increase of kV settings made the values of CTDIair increased as well. When the kV setting was changed from 80 kV to 120 kV and from 120 kV to 140 kV, the CTDIair values were increased as much as 147.9% and 53.9% respectively. The highest kV setting (140 kV) led to the highest CTDIair value (13.585 mGy). The p-value of less than 0.05 indicated that the results were statistically different. The SSDP showed that when the kV settings were varied, the peak sharpness and height of Gaussian function profiles were affected. The full width at half maximum (FWHM) of dose profiles for all protocols were coincided with the nominal beam width set for the measurements. The findings of the study revealed much information on the characterization and performance of 128 slice CT scanner.

Kuipers works with DSC Hardware in the U.S. Laboratory

NASA Image and Video Library

2012-01-16

ISS030-E-155917 (16 Jan. 2012) --- European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, prepares to place Diffusion Soret Coefficient (DSC) hardware in stowage containers in the Destiny laboratory of the International Space Station.

Thermally stimulated properties in ZnSe:Tb and ZnSe:(Mn, Tb) phosphors

NASA Astrophysics Data System (ADS)

Mishra, A. K.; Mishra, S. K.; Pandey, S. P.; Lakshmi Mishra, Kshama

2018-02-01

Thermoluminescence studies were performed of ZnSe:Tb and ZnSe:(Mn, Tb) phosphors. A method of preparation for ZnSe phosphors doped with Tb and (Mn, Tb) has been discussed. The thermoluminescence (TL) properties of these phosphors have been studied from 100 to 370 K temperature after exciting by UV radiation (365 nm) at three uniform heating rates 0.4, 0.6 and 0.9 K/s. The trapping parameters like trap depth, lifetime of electrons and capture cross-section have also been determined using various methods.

Preparation and Analysis of Libethenite: A Project for the First-Year Laboratory

ERIC Educational Resources Information Center

Ginion, Kelly E.; Yoder, Claude H.

2004-01-01

The preparation of libethenite, a double salt of copper(II) phosphate and copper(II) hydroxide presents the opportunity to discuss the prevalence of double salts in the environment, the relationship between solubility and stability in aqueous solution, the origin of the color of transition metal compounds and gravimetric analyses. Typical results…

Synthesis and Application of Ratiometric and "Turn-On" Fluorescent pH Sensors: An Advanced Organic Undergraduate Laboratory

ERIC Educational Resources Information Center

Hutt, Johnathon T.; Aron, Zachary D.

2014-01-01

An upper-division organic chemistry laboratory experiment exploring fluorescent sensing over two laboratory periods and part of a third is described. Two functionally distinct pH-responsive sensors are prepared through a dehydrative three-component coupling reaction. During the abbreviated (<1 h) first laboratory period, students set up…

Effect of 100 MeV swift Si8+ ions on structural and thermoluminescence properties of Y2O3:Dy3+nanophosphor

NASA Astrophysics Data System (ADS)

Shivaramu, N. J.; Lakshminarasappa, B. N.; Nagabhushana, K. R.; Singh, Fouran

2016-05-01

Nanoparticles of Y2O3:Dy3+ were prepared by the solution combustion method. The X-ray diffraction pattern of the 900°C annealed sample shows a cubic structure and the average crystallite size was found to be 31.49 nm. The field emission scanning electron microscopy image of the 900°C annealed sample shows well-separated spherical shape particles and the average particle size is found to be in a range 40 nm. Pellets of Y2O3:Dy3+ were irradiated with 100 MeV swift Si8+ ions for the fluence range of 3 × 1011_3 × 1013 ions cm-2. Pristine Y2O3:Dy3+ shows seven Raman modes with peaks at 129, 160, 330, 376, 434, 467 and 590 cm-1. The intensity of these modes decreases with an increase in ion fluence. A well-resolved thermoluminescence glow with peaks at ∼414 K (Tm1) and ∼614 K (Tm2) were observed in Si8+ ion-irradiated samples. It is found that glow peak intensity at 414 K increases with an increase in the dopant concentration up to 0.6 mol% and then decreases with an increase in dopant concentration. The high-temperature glow peak (614 K) intensity linearly increases with an increase in ion fluence. The broad TL glow curves were deconvoluted using the glow curve deconvoluted method and kinetic parameters were calculated using the general order kinetic equation.

A Pollutant Transformation Laboratory Exercise for Environmental Chemistry: The Reduction of Nitrobenzenes by Anaerobic Solutions of Humic Acid

ERIC Educational Resources Information Center

Dunnivant, Frank M.; Reynolds, Mark-Cody

2007-01-01

The laboratory experiment, which acts as a capstone, integrated lecture-laboratory exercise involving solution preparation, pH buffers, [E[subscript]H] (reduction potential) buffers, organic reaction mechanisms, reaction kinetics, and instrumental analysis is presented. The students completing the lecture and laboratory exercises could gain a…

Synthesis and characterization of novel Na15 (SO4 )5 F4 Cl:Ce3+ halosulfate phosphors.

PubMed

Bhake, A M; Nair, Govind B; Zade, G D; Dhoble, S J

2016-12-01

A series of Na 15 (SO 4 ) 5 F 4 Cl phosphors doped with Ce 3+ ions was prepared using the wet chemical method. X-Ray diffraction studies were used to determine their phase formation and purity. Fourier transform infrared spectroscopy effectively identified the chemical bonds present in the molecule. The photoluminescence properties of the as-prepared phosphors were investigated and the Ce 3+ ions in these hosts were found to give broadband emission in the UV range. For the thermoluminescence study, phosphors were irradiated with a 5 Gy dose of γ-rays from a 60 Co source. Chen's half-width method was employed to calculate the trapping parameters from the thermoluminescence glow curve. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

LUNAR RECEIVING LABORATORY (LRL) - CLARK, ROBERT, DR. - JSC

NASA Image and Video Library

1973-11-05

S73-36161 (November 1973) --- In the Radiation Counting Laboratory sixty feet underground at JSC, Dr. Robert S. Clark prepares to load pieces of iridium foil -- sandwiched between plastic sheets -- into the laboratory's radiation detector. The iridium foil strips were worn by the crew of the second Skylab flight in personal radiation dosimeters throughout their 59 1/2 days in space. Inside the radiation detector assembly surrounded by 28 tons of lead shielding, the sample will be tested to determine the total neutron dose to which the astronauts were exposed during their long stay aboard the space station. Photo credit: NASA

21 CFR 660.25 - Potency tests without reference preparations.

Code of Federal Regulations, 2012 CFR

2012-04-01

... manufacturer's package insert using red blood cells showing heterozygous or diminished expression of the... SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.25 Potency tests without reference preparations. Products for which Reference Blood...

21 CFR 660.25 - Potency tests without reference preparations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... manufacturer's package insert using red blood cells showing heterozygous or diminished expression of the... SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.25 Potency tests without reference preparations. Products for which Reference Blood...

21 CFR 660.25 - Potency tests without reference preparations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... manufacturer's package insert using red blood cells showing heterozygous or diminished expression of the... SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.25 Potency tests without reference preparations. Products for which Reference Blood...

21 CFR 660.25 - Potency tests without reference preparations.

Code of Federal Regulations, 2011 CFR

2011-04-01

... manufacturer's package insert using red blood cells showing heterozygous or diminished expression of the... SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.25 Potency tests without reference preparations. Products for which Reference Blood...

21 CFR 660.25 - Potency tests without reference preparations.

Code of Federal Regulations, 2013 CFR

2013-04-01

... manufacturer's package insert using red blood cells showing heterozygous or diminished expression of the... SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.25 Potency tests without reference preparations. Products for which Reference Blood...

Rupture preparation process controlled by surface roughness on meter-scale laboratory fault

NASA Astrophysics Data System (ADS)

Yamashita, Futoshi; Fukuyama, Eiichi; Xu, Shiqing; Mizoguchi, Kazuo; Kawakata, Hironori; Takizawa, Shigeru

2018-05-01

We investigate the effect of fault surface roughness on rupture preparation characteristics using meter-scale metagabbro specimens. We repeatedly conducted the experiments with the same pair of rock specimens to make the fault surface rough. We obtained three experimental results under the same experimental conditions (6.7 MPa of normal stress and 0.01 mm/s of loading rate) but at different roughness conditions (smooth, moderately roughened, and heavily roughened). During each experiment, we observed many stick-slip events preceded by precursory slow slip. We investigated when and where slow slip initiated by using the strain gauge data processed by the Kalman filter algorithm. The observed rupture preparation processes on the smooth fault (i.e. the first experiment among the three) showed high repeatability of the spatiotemporal distributions of slow slip initiation. Local stress measurements revealed that slow slip initiated around the region where the ratio of shear to normal stress (τ/σ) was the highest as expected from finite element method (FEM) modeling. However, the exact location of slow slip initiation was where τ/σ became locally minimum, probably due to the frictional heterogeneity. In the experiment on the moderately roughened fault, some irregular events were observed, though the basic characteristics of other regular events were similar to those on the smooth fault. Local stress data revealed that the spatiotemporal characteristics of slow slip initiation and the resulting τ/σ drop for irregular events were different from those for regular ones even under similar stress conditions. On the heavily roughened fault, the location of slow slip initiation was not consistent with τ/σ anymore because of the highly heterogeneous static friction on the fault, which also decreased the repeatability of spatiotemporal distributions of slow slip initiation. These results suggest that fault surface roughness strongly controls the rupture preparation process

H. W. Laboratory manual: 100 Area section

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

Not Available

1950-07-01

The purpose of this manual is to present a Hazard Breakdown of all jobs normally encountered in the laboratory work of the three sections comprising the Analytic Section, Metallurgy and Control Division of the Technical Department. A Hazard Breakdown is a careful analysis of any job in which the source of possible dangers is clearly indicated for each particular step. The analysis is prepared by individuals who are thoroughly familiar with the specific job or procedure. It is felt that if the hazards herein outlined are recognized by the Laboratory personnel and the suggested safety cautions followed, the chance formore » injury will be minimized and the worker will become generally more safety conscious. The manual, which is prefaced by the general safety rules applying to all the laboratories, is divided into three main sections, one for each of the three sections into which the Laboratories Division is divided. These sections are as follows: Section 1 -- 200 Area Control; Section 2 -- 100 Area Control; Section 3 -- 300 Area Control, Essential Materials, and Methods Improvement.« less

Preparation and characterization of a laboratory scale selenomethionine-enriched bread. Selenium bioaccessibility.

PubMed

Sánchez-Martínez, María; Pérez-Corona, Teresa; Caímara, Carmen; Madrid, Yolanda

2015-01-14

This study focuses on the preparation at lab scale of selenomethionine-enriched white and wholemeal bread. Selenium was supplemented either by adding selenite directly to the dough or by using lab-made selenium-enriched yeast. The best results were obtained when using fresh selenium-enriched yeast. The optimum incubation time for selenomethionine-enriched yeast preparation, while keeping formation of selenium byproducts to a minimum, was 96 h. Selenium content measured by isotope dilution analysis (IDA)-ICP-MS in Se-white and Se-wholemeal bread was 1.28 ± 0.02 μg g–1 and 1.16 ± 0.02 μg g–1 (expressed as mean ± SE, 3 replicates), respectively. HPLC postcolumn IDA-ICP-MS measurements revealed that selenomethionine was the main Se species found in Se-enriched bread, which accounted for ca. 80% of total selenium. In vitro gastrointestinal digestion assay provided selenium bioaccessibility values of 100 ± 3% and 40 ± 1% for white and wholemeal Se-enriched bread, respectively, being selenomethionine the main bioaccessible Se species in white bread, while in wholemeal bread this compound was undetectable.

The State Laboratory of Hygiene's role in terrorism preparedness and response.

PubMed

Hintzman, Peggy L

2003-01-01

In the fall of 2001, the national public health system found itself responding to acts of terrorism. The intentional release of Bacillus anthracis spores on the East Coast tested the capacity of all state public health laboratories to respond. The impact on the public health system extended to the Wisconsin State Laboratory of Hygiene (WSLH). Fortunately, participation in the National Laboratory Response Network helped the WSLH meet the challenge of 24 hour/7 days a week coverage, and subsequent federal funding increases have enabled the WSLH to expand its technical capabilities and provide training and outreach to other Wisconsin laboratories to prepare them for their roles in man-made or naturally-occurring public health emergencies.

Hair analysis for cocaine: factors in laboratory contamination studies and their relevance to proficiency sample preparation and hair testing practices.

PubMed

Hill, Virginia; Cairns, Thomas; Schaffer, Michael

2008-03-21

Hair samples were contaminated by rubbing with cocaine (COC) followed by sweat application, multiple shampoo treatments and storage. The samples were then washed with isopropanol for 15min, followed by sequential aqueous washes totaling 3.5h. The amount of drug in the last wash was used to calculate a wash criterion to determine whether samples were positive due to use or contamination. Analyses of cocaine and metabolites were done by LC/MS/MS. These procedures were applied to samples produced by a U.S. government-sponsored cooperative study, in which this laboratory participated, and to samples in a parallel in-house study. All contaminated samples in both studies were correctly identified as contaminated by cutoff, benzoylecgonine (BE) presence, BE ratio, and/or the wash criterion. A method for determining hair porosity was applied to samples in both studies, and porosity characteristics of hair are discussed as they relate to experimental and real-world contamination of hair, preparation of proficiency survey samples, and analysis of unknown hair samples.

Analysis of Potassium in Bricks--Determining the Dose Rate from {sup 40}K for Thermoluminescence Dating

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

Musilek, Ladislav; Polach, Tomas; Trojek, Tomas

2008-08-07

Thermoluminescence (TL) dating is based on accumulating the natural radiation dose in the material of a dated artefact (brick, pottery, etc.), and comparing the dose accumulated during the lifetime of the object with the dose rate within the sample collected for TL measurement. Determining the dose rate from natural radionuclides in materials is one of the most important and most difficult parts of the technique. The most important radionuclides present are usually nuclides of the uranium and thorium decay series and {sup 40}K. An analysis of the total potassium concentration enables us to determine the {sup 40}K content effectively, andmore » from this it is possible to calculate the dose rate originating from this radiation source. X-ray fluorescence (XRF) analysis can be used to determine the potassium concentration in bricks rapidly and efficiently. The procedure for analysing potassium, examples of results of dose rate calculation and possible sources of error are described here.« less

Observing Animal Behavior at the Zoo: A Learning Laboratory

ERIC Educational Resources Information Center

Hull, Debra B.

2003-01-01

Undergraduate students in a learning laboratory course initially chose a species to study; researched that species' physical and behavioral characteristics; then learned skills necessary to select, operationalize, observe, and record animal behavior accurately. After their classroom preparation, students went to a local zoo to observe the behavior…

Speak Up: Help Prevent Errors in Your Care: Laboratory Services

MedlinePlus

... chose that particular laboratory. • Prepare for the lab test by asking questions. For example, ask if there are any foods, drinks or medicines that you should not take before the test. • Write down information that your doctor tells you. ...

Developing Medicare Competitive Bidding: A Study of Clinical Laboratories

PubMed Central

Hoerger, Thomas J.; Meadow, Ann

1997-01-01

Competitive bidding to derive Medicare fees promises several advantages over administered fee systems. The authors show how incentives for cost savings, quality, and access can be incorporated into bidding schemes, and they report on a study of the clinical laboratory industry conducted in preparation for a bidding demonstration. The laboratory industry is marked by variable concentration across geographic markets and, among firms themselves, by social and economic heterogeneity. The authors conclude that these conditions can be accommodated by available bidding design options and by careful selection of bidding markets. PMID:10180003

Preparation and Spectrophotometric Analysis of Hexaamminenickel(II) Chloride.

ERIC Educational Resources Information Center

Wieder, Grace M.

1986-01-01

Describes an experiment developed at Brooklyn College (New York) in which the preparation and ammonia analysis of an amminenickel(II) chloride is extended to include a spectrophotometric analysis for nickel. Discusses the materials needed and the procedure for the experiment which takes nine hours of laboratory work. (TW)

RCT: Module 2.04, Dosimetry, Course 8769

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

Hillmer, Kurt T.

This course will introduce the types of instruments used to measure external and internal radiation to people. Dosimetry is the quantitative assessment of radiation received by the human body. Several types of dosimeters are used worldwide. This information is valuable to all radiological control personnel because dosimeters are the only direct method to measure and document personnel radiation exposure and ensure regulatory compliance with applicable limits. This course will cover dosimetry terms, Department of Energy (DOE) limits, Los Alamos National Laboratory (LANL) administrative guidelines, thermoluminescent dosimeters (TLDs), LANL dosimetry, and bioassay assessment methods. This course will prepare the student withmore » the skills necessary for radiological control technician (RCT) qualification by passing quizzes, tests, and the RCT Comprehensive Phase 1, Unit 2 Examination (TEST 27566) and providing in-thefield skills.« less

Invention activities as preparation for learning laboratory data handling skills

NASA Astrophysics Data System (ADS)

Day, James

2012-10-01

Undergraduate physics laboratories are often driven by a mix of goals, and usually enough of them to cause cognitive overload for the student. Our recent findings align well with studies indicating that students often exit a physics lab without having properly learned how to handle real data. The value of having students explore the underlying structure of a problem before being able to solve it has been shown as an effective way to ready students for learning. Borrowing on findings from the fields of education and cognitive psychology, we use ``invention activities'' to precede direct instruction and bolster learning. In this talk I will show some of what we have learned about students' data handling skills, explain how an invention activity works, and share some observations of successful transfer.

Laboratory Information Management Systems for Forensic Laboratories: A White Paper for Directors and Decision Makers

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

Anthony Hendrickson; Brian Mennecke; Kevin Scheibe

2005-10-01

Modern, forensics laboratories need Laboratory Information Management Systems (LIMS) implementations that allow the lab to track evidentiary items through their examination lifecycle and also serve all pertinent laboratory personnel. The research presented here presents LIMS core requirements as viewed by respondents serving in different forensic laboratory capacities as well as different forensic laboratory environments. A product-development methodology was employed to evaluate the relative value of the key features that constitute a LIMS, in order to develop a set of relative values for these features and the specifics of their implementation. In addition to the results of the product development analysis,more » this paper also provides an extensive review of LIMS and provides an overview of the preparation and planning process for the successful upgrade or implementation of a LIMS. Analysis of the data indicate that the relative value of LIMS components are viewed differently depending upon respondents' job roles (i.e., evidence technicians, scientists, and lab management), as well as by laboratory size. Specifically, the data show that: (1) Evidence technicians place the most value on chain of evidence capabilities and on chain of custody tracking; (2) Scientists generally place greatest value on report writing and generation, and on tracking daughter evidence that develops during their analyses; (3) Lab. Managers place the greatest value on chain of custody, daughter evidence, and not surprisingly, management reporting capabilities; and (4) Lab size affects LIMS preference in that, while all labs place daughter evidence tracking, chain of custody, and management and analyst report generation as their top three priorities, the order of this prioritization is size dependent.« less

Proceedings of the NASA Laboratory Astrophysics Workshop

NASA Technical Reports Server (NTRS)

Weck, Phillippe F. (Editor); Kwong, Victor H. S. (Editor); Salama, Farid (Editor)

2006-01-01

This report is a collection of papers presented at the 2006 NASA Workshop on Laboratory Astrophysics held in the University of Nevada, Las Vegas (UNLV) from February 14 to 16, 2006. This workshop brings together producers and users of laboratory astrophysics data so that they can understand each other's needs and limitations in the context of the needs for NASA's missions. The last NASA-sponsored workshop was held in 2002 at Ames Research Center. Recent related meetings include the Topical Session at the AAS meeting and the European workshop at Pillnitz, Germany, both of which were held in June 2005. The former showcased the importance of laboratory astrophysics to the community at large, while the European workshop highlighted a multi-laboratory approach to providing the needed data. The 2006 NASA Workshop on Laboratory Astrophysics, sponsored by the NASA Astrophysics Division, focused on the current status of the field and its relevance to NASA. This workshop attracted 105 participants and 82 papers of which 19 were invited. A White Paper identifying the key issues in laboratory astrophysics during the break-out sessions was prepared by the Scientific Organizing Committee, and has been forwarded to the Universe Working Group (UWG) at NASA Headquarters. This White Paper, which represented the collective inputs and opinions from experts and stakeholders in the field of astrophysics, should serve as the working document for the future development of NASA's R&A program in laboratory astrophysics.

Clinical Chemistry Laboratory Automation in the 21st Century - Amat Victoria curam (Victory loves careful preparation)

PubMed Central

Armbruster, David A; Overcash, David R; Reyes, Jaime

2014-01-01

The era of automation arrived with the introduction of the AutoAnalyzer using continuous flow analysis and the Robot Chemist that automated the traditional manual analytical steps. Successive generations of stand-alone analysers increased analytical speed, offered the ability to test high volumes of patient specimens, and provided large assay menus. A dichotomy developed, with a group of analysers devoted to performing routine clinical chemistry tests and another group dedicated to performing immunoassays using a variety of methodologies. Development of integrated systems greatly improved the analytical phase of clinical laboratory testing and further automation was developed for pre-analytical procedures, such as sample identification, sorting, and centrifugation, and post-analytical procedures, such as specimen storage and archiving. All phases of testing were ultimately combined in total laboratory automation (TLA) through which all modules involved are physically linked by some kind of track system, moving samples through the process from beginning-to-end. A newer and very powerful, analytical methodology is liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). LC-MS/MS has been automated but a future automation challenge will be to incorporate LC-MS/MS into TLA configurations. Another important facet of automation is informatics, including middleware, which interfaces the analyser software to a laboratory information systems (LIS) and/or hospital information systems (HIS). This software includes control of the overall operation of a TLA configuration and combines analytical results with patient demographic information to provide additional clinically useful information. This review describes automation relevant to clinical chemistry, but it must be recognised that automation applies to other specialties in the laboratory, e.g. haematology, urinalysis, microbiology. It is a given that automation will continue to evolve in the clinical laboratory

Clinical Chemistry Laboratory Automation in the 21st Century - Amat Victoria curam (Victory loves careful preparation).

PubMed

Armbruster, David A; Overcash, David R; Reyes, Jaime

2014-08-01

The era of automation arrived with the introduction of the AutoAnalyzer using continuous flow analysis and the Robot Chemist that automated the traditional manual analytical steps. Successive generations of stand-alone analysers increased analytical speed, offered the ability to test high volumes of patient specimens, and provided large assay menus. A dichotomy developed, with a group of analysers devoted to performing routine clinical chemistry tests and another group dedicated to performing immunoassays using a variety of methodologies. Development of integrated systems greatly improved the analytical phase of clinical laboratory testing and further automation was developed for pre-analytical procedures, such as sample identification, sorting, and centrifugation, and post-analytical procedures, such as specimen storage and archiving. All phases of testing were ultimately combined in total laboratory automation (TLA) through which all modules involved are physically linked by some kind of track system, moving samples through the process from beginning-to-end. A newer and very powerful, analytical methodology is liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). LC-MS/MS has been automated but a future automation challenge will be to incorporate LC-MS/MS into TLA configurations. Another important facet of automation is informatics, including middleware, which interfaces the analyser software to a laboratory information systems (LIS) and/or hospital information systems (HIS). This software includes control of the overall operation of a TLA configuration and combines analytical results with patient demographic information to provide additional clinically useful information. This review describes automation relevant to clinical chemistry, but it must be recognised that automation applies to other specialties in the laboratory, e.g. haematology, urinalysis, microbiology. It is a given that automation will continue to evolve in the clinical laboratory

Illinois Occupational Skill Standards: Clinical Laboratory Science/Biotechnology Cluster.

ERIC Educational Resources Information Center

Illinois Occupational Skill Standards and Credentialing Council, Carbondale.

This document, which is intended to serve as a guide for workforce preparation program providers, details the Illinois Occupational Skill Standards for clinical laboratory occupations programs. The document begins with a brief overview of the Illinois perspective on occupational skill standards and credentialing, the process used to develop the…

Thermoluminescence dosimetry and its applications in medicine--Part 2: History and applications.

PubMed

Kron, T

1995-03-01

Thermoluminescence dosimetry (TLD) has been available for dosimetry of ionising radiation for nearly 100 years. The variety of materials and their different physical forms allow the determination of different radiation qualities over a wide range of absorbed dose. This makes TL dosimeters useful in radiation protection where dose levels of microGy are monitored as well as in radiotherapy where doses up to several Gray are to be measured. The major advantages of TL detectors are their small physical size and that no cables or auxiliary equipment is required during the dose assessment. Therefore TLD is a good method for point dose measurements in phantoms as well as for in vivo dosimetry on patients during radiotherapy treatment. As an integrative dosimetric technique, it can be applied to personal dosimetry and it lends itself to the determination of dose distributions due to multiple or moving radiation sources (e.g. conformal and dynamic radiotherapy, computed tomography). In addition, TL dosimeters are easy to transport, and they can be mailed. This makes them well suited for intercomparison of doses delivered in different institutions. The present article aims at describing the various applications TLD has found in medicine by taking into consideration the physics and practice of TLD measurements which have been discussed in the first part of this review (Australas. Phys. Eng. Sci. Med. 17: 175-199, 1994).

[Standardization of terminology in laboratory medicine I].

PubMed

Yoon, Soo Young; Yoon, Jong Hyun; Min, Won Ki; Lim, Hwan Sub; Song, Junghan; Chae, Seok Lae; Lee, Chang Kyu; Kwon, Jung Ah; Lee, Kap No

2007-04-01

Standardization of medical terminology is essential for data transmission between health-care institutions or clinical laboratories and for maximizing the benefits of information technology. Purpose of our study was to standardize the medical terms used in the clinical laboratory, such as test names, units, terms used in result descriptions, etc. During the first year of the study, we developed a standard database of concept names for laboratory terms, which covered the terms used in government health care centers, their branch offices, and primary health care units. Laboratory terms were collected from the electronic data interchange (EDI) codes from National Health Insurance Corporation (NHIC), Logical Observation Identifier Names and Codes (LOINC) database, community health centers and their branch offices, and clinical laboratories of representative university medical centers. For standard expression, we referred to the English-Korean/ Korean-English medical dictionary of Korean Medical Association and the rules for foreign language translation. Programs for mapping between LOINC DB and EDI code and for translating English to Korean were developed. A Korean standard laboratory terminology database containing six axial concept names such as components, property, time aspect, system (specimen), scale type, and method type was established for 7,508 test observations. Short names and a mapping table for EDI codes and Unified Medical Language System (UMLS) were added. Synonym tables for concept names, words used in the database, and six axial terms were prepared to make it easier to find the standard terminology with common terms used in the field of laboratory medicine. Here we report for the first time a Korean standard laboratory terminology database for test names, result description terms, result units covering most laboratory tests in primary healthcare centers.

Preparation and Characterization of Polymeric Nanoparticles: An Interdisciplinary Experiment

ERIC Educational Resources Information Center

Ramalho, Maria J.; Pereira, M. Carmo

2016-01-01

In this work, a laboratory experiment to introduce graduate students to nanotechnology is described. Students prepared poly(lactic-"co"-glycolic acid) (PLGA) nanoparticles using two different synthesis procedures, a single and a double emulsion-solvent evaporation method. The students also performed a physicochemical characterization of…

Preparing for Solar and Thermal Testing of Curiosity Mars Rover

NASA Image and Video Library

2011-03-18

This image shows preparation for March 2011 testing of the Mars Science Laboratory rover, Curiosity, in a space-simulation chamber; the rover will go through operational sequences in environmental conditions similar to what it will experience on Mars.

Clinical laboratory technician to clinical laboratory scientist articulation and distance learning.

PubMed

Crowley, J R; Laurich, G A; Mobley, R C; Arnette, A H; Shaikh, A H; Martin, S M

1999-01-01

Laboratory workers and educators alike are challenged to support access to education that is current and provides opportunities for career advancement in the work place. The clinical laboratory science (CLS) program at the Medical College of Georgia in Augusta developed a clinical laboratory technician (CLT) to CLS articulation option, expanded it through distance learning, and integrated computer based learning technology into the educational process over a four year period to address technician needs for access to education. Both positive and negative outcomes were realized through these efforts. Twenty-seven students entered the pilot articulation program, graduated, and took a CLS certification examination. Measured in terms of CLS certification, promotions, pay raises, and career advancement, the program described was a success. However, major problems were encountered related to the use of unfamiliar communication technology; administration of the program at distance sites; communication between educational institutions, students, and employers; and competition with CLT programs for internship sites. These problems must be addressed in future efforts to provide a successful distance learning program. Effective methods for meeting educational needs and career ladder expectations of CLTs and their employers are important to the overall quality and appeal of the profession. Educational technology that includes computer-aided instruction, multimedia, and telecommunications can provide powerful tools for education in general and CLT articulation in particular. Careful preparation and vigilant attention to reliable delivery methods as well as students' progress and outcomes is critical for an efficient, economically feasible, and educationally sound program.

Atomization of metal (Materials Preparation Center)

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

None

2010-01-01

Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a color video of a liquid metal stream being atomized by high pressure gas. This material was cast at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov WARNING - AUDIO IS LOUD.

Scientific equity: experiments in laboratory education in Ghana.

PubMed

Osseo-Asare, Abena Dove

2013-12-01

During the 1960s the Ministry of Education in Ghana created a network of school laboratories to increase scientific literacy among young citizens. The ministry stocked these "Science Centres" with imported beakers, Bunsen burners, and books. Education officials and university scientists worked with teachers to create lesson plans on water, air, plants, and other topics. The government hoped that scientifically minded schoolchildren would be better prepared to staff the industries of the future. The adoption of laboratory norms represented a desire for scientific equity, rather than a condition of cultural mimicry. Interviews with ministry officials and science educators, alongside letters and reports, indicate how students and teachers appropriated the laboratories in the small West African nation. Their experiences in mobilizing resources from across Ghana and around the world provide a metaphor for ongoing efforts to establish access to scientific goods in Africa.

A Sustainable Energy Laboratory Course for Non-Science Majors

ERIC Educational Resources Information Center

Nathan, Stephen A.; Loxsom, Fred

2016-01-01

Sustainable energy is growing in importance as the public becomes more aware of climate change and the need to satisfy our society's energy demands while minimizing environmental impacts. To further this awareness and to better prepare a workforce for "green careers," we developed a sustainable energy laboratory course that is suitable…

Laboratory techniques for human embryos.

PubMed

Geber, Selmo; Sales, Liana; Sampaio, Marcos A C

2002-01-01

This review is concerned with laboratory techniques needed for assisted conception, particularly the handling of gametes and embryos. Such methods are being increasingly refined. Successive stages of fertilization and embryogenesis require especial care, and often involve the use of micromanipulative methods for intracytoplasmic sperm injection (ICSI) or preimplantation genetic diagnosis. Embryologists must take responsibility for gamete collection and preparation, and for deciding on the means of insemination or ICSI. Embryos must be assessed in culture, during the 1-cell, cleaving and morula/blastocyst stages, and classified according to quality. Co-culture methods may be necessary. The best embryos for transfer must be selected and loaded into the transfer catheter. Embryos not transferred must be cryopreserved, which demands the correct application of current methods of media preparation, seeding and the correct speed for cooling and warming. Before too long, methods of detecting abnormal embryos and avoiding their transfer may become widespread.

Innovative ventilation system for animal anatomy laboratory

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

Lacey, D.R.; Smith, D.C.

1997-04-01

A unique ventilation system was designed and built to reduce formaldehyde fumes in the large animal anatomy lab at the Vet Medical Center at Cornell University. The laboratory includes four rooms totaling 5,500 ft{sup 2}. The main room has 2,300 ft{sup 2} and houses the laboratory where up to 60 students dissect as many as 12 horses at a time. Other rooms are a cold storage locker, an animal preparation room and a smaller lab for specialized instruction. The large animal anatomy laboratory has a history of air quality complaints despite a fairly high ventilation rate of over 10 airmore » changes/hour. The horses are embalmed, creating a voluminous source of formaldehyde and phenol vapors. Budget constraints and increasingly stringent exposure limits for formaldehyde presented a great challenge to design a ventilation system that yields acceptable air quality. The design solution included two innovative elements: air-to-air heat recovery, and focused ventilation.« less

Teaching Embryology without Lectures and without Traditional Laboratories--An Adventure in Innovation.

ERIC Educational Resources Information Center

Heady, Judith E.

1993-01-01

Describes problems with teaching embryology in the traditional manner. Presents a new approach where students prepare presentations, questions, and discussion topics. During laboratory periods, students conducted their own long-term research projects. (PR)

Lipid and lipoprotein testing in resource-limited laboratories.

PubMed

Myers, Gary L

2003-01-01

The role of total cholesterol (TC) and lipoproteins in the assessment of coronary heart disease (CHD) is firmly established from population and intervention studies. Total and low-density lipoprotein cholesterol (LDLC) levels are positively associated with CHD, and high-density lipoprotein cholesterol (HDLC) levels are negatively associated with CHD. Efforts to identify and treat people at increased risk based on cholesterol and lipoprotein levels have led to more lipid testing and the need for very reliable test results. Thus, quality laboratory services are an essential component of healthcare delivery and play a vital role in any strategy to reduce morbidity and mortality from CHD. In laboratories with limited resources, establishing laboratory capability to measure CHD risk markers may be a considerable challenge. Laboratories face problems in selecting proper techniques, difficulties in equipment availability and maintenance, and shortage of supplies, staffing, and supervision. The Centers for Disease Control and Prevention (CDC) has been providing technical assistance for more than 30 years to laboratories that measure lipids and lipoproteins and is willing to provide technical assistance as needed for other laboratories to develop this capability. CDC can provide technical assistance to establish lipid and lipoprotein testing capability to support a CHD public health program in areas with limited laboratory resources. This assistance includes: selecting a suitable testing instrument; providing training for laboratory technicians; establishing a simple quality control plan; and instructing staff on how to prepare frozen serum control materials suitable for assessing accuracy of lipid and lipoprotein testing.

WHO Expert Committee on specifications for pharmaceutical preparations.

PubMed

2010-01-01

The Expert Committee on Specifications for Pharmaceutical Preparations works towards clear, independent and practical standards and guidelines for the quality assurance of medicines. Standards are developed by the Committee through worldwide consultation and an international consensus-building process. The following new guidelines were adopted and recommended for use: good practices for pharmaceutical quality control laboratories; supplementary guidelines for active pharmaceutical ingredients; good manufacturing practices for pharmaceutical products containing hazardous substances; good manufacturing practices for sterile pharmaceutical products; good distribution practices for pharmaceutical products; guidelines on the requalification of prequalified dossiers: and guidelines for the preparation of a contract research organization master file.

STS-100 crewmembers prepare to train in NBL

NASA Image and Video Library

2000-12-01

JSC2000-07391 (1 December 2000)--- Astronaut Chris A. Hadfield, representing the Canadian Space Agency (CSA), puts final touches on the suit-up process in preparation for a training session in the Neutral Buoyancy Laboratory (NBL) near the Johnson Space Center (JSC). Hadfield is designated for space walk duty on the STS-100 flight, and underwater simulations of his duties help prepare him for the mission, scheduled for spring of next year. By coincidence, Hadfield is aligned beneath the Canadian flag, one of the many on NBL walls which pay tribute to the participating international partners.

Strategies of organization and service for the critical-care laboratory.

PubMed

Fleisher, M; Schwartz, M K

1990-08-01

Critical-care medicine requires rapidity of treatment decisions and clinical management. To meet the objectives of critical-care medicine, the critical-care laboratory must consider four major aspects of laboratory organization in addition to analytical responsibilities: specimen collection and delivery, training of technologists, selection of reliable instrumentation, and efficient data dissemination. One must also consider the advantages and disadvantages of centralization vs decentralization, the influence of such a laboratory on patient care and personnel needs, and the space required for optimal operation. Centralization may lead to workflow interruption and increased turnaround time (TAT); decentralization requires redundancy of instrumentation and staff but may shorten TAT. Minimal TAT is the hallmark of efficient laboratory service. We surveyed 55 laboratories in 33 hospitals and found that virtually all hospitals with 200 or more beds had a critical-care laboratory operating as a satellite of the main laboratory. We present data on actual TAT, although these were available in only eight of the 15 routine laboratories that provided emergency service and in eight of the 40 critical-care laboratories. In meeting the challenges of an increasing workload, a reduced clinical laboratory work force, and the need to reduce TAT, changes in traditional laboratory practice are mandatory. An increased reliance on whole-blood analysis, for example, should eliminate delays associated with sample preparation, reduce the potential hazards associated with centrifugation, and eliminate excess specimen handling.

International reference preparations of typhoid vaccine

PubMed Central

Melikova, E. N.; Lesnjak, S. V.

1967-01-01

International collaborative laboratory studies on the International Reference Preparations of Typhoid Vaccine have so far failed to provide data on which international units for these vaccines can be based. Further assays carried out using the active mouse protection test, with immunization by the subcutaneous, intraperitoneal or intravenous route, confirmed the findings by some workers that the International Reference Preparation of Typhoid Vaccine (Acetone-Inactivated) (vaccine K) was more effective than the International Reference Preparation of Typhoid Vaccine (Heat-Phenol-Inactivated) (vaccine L), and indicated that intraperitoneal immunization was the most promising method. Vaccine K, together with the material extracted by the acetone in the preparation of the vaccine, had a significantly lower effectiveness (at the 5% probability level) only when intraperitoneal immunization was used. The reasons for the differences found between the various vaccines and routes of immunization are discussed at length. It is suggested that challenge with a strain of Salmonella moscow instead of the strain of Salm. typhi used until now gives a true infection and forms the basis of a reliable method for the potency assay of typhoid vaccines. PMID:5301738

Aids in designing laboratory flumes

USGS Publications Warehouse

Williams, Garnett P.

1971-01-01

The upsurge of interest in our environment has caused research and instruction in the flow of water along open channels to become increasingly popular in universities and institutes. This, in turn, has brought a greater demand for properly-designed laboratory flumes. Whatever the reason for your interest, designing and building the flume will take a little preparation. You may choose a pattern exactly like a previous design, or you may follow the more time-consuming method of studying several existing flumes and combine the most desirable features of each.

Effluent-Monitoring Procedures: Basic Laboratory Skills. Student Reference Manual.

ERIC Educational Resources Information Center

Engel, William T.; And Others

This is one of several short-term courses developed to assist in the training of waste water treatment plant operational personnel in the tests, measurements, and report preparation required for compliance with their NPDES Permits. This Student Reference Manual provides a review of basic mathematics as it applies to the chemical laboratory. The…

A laboratory medicine residency training program that includes clinical consultation and research.

PubMed

Spitzer, E D; Pierce, G F; McDonald, J M

1990-04-01

We describe a laboratory medicine residency training program that includes ongoing interaction with both clinical laboratories and clinical services as well as significant research experience. Laboratory medicine residents serve as on-call consultants in the interpretation of test results, design of testing strategies, and assurance of test quality. The consultative on-call beeper system was evaluated and is presented as an effective method of clinical pathology training that is well accepted by the clinical staff. The research component of the residency program is also described. Together, these components provide training in real-time clinical problem solving and prepare residents for the changing technological environment of the clinical laboratory. At the completion of the residency, the majority of the residents are qualified laboratory subspecialists and are also capable of running an independent research program.

Laboratory fire behavior measurements of chaparral crown fire

Treesearch

C. Sanpakit; S. Omodan; D. Weise; M Princevac

2015-01-01

In 2013, there was an estimated 9,900 wildland fires that claimed more than 577,000 acres of land. That same year, about 542 prescribed fires were used to treat 48,554 acres by several agencies in California. Being able to understand fires using laboratory models can better prepare individuals to combat or use fires. Our research focused on chaparral crown fires....

A Laboratory Exercise to Illustrate Protein-Membrane Interactions

ERIC Educational Resources Information Center

Weers, Paul M. M.; Prenner, Elmar J.; Curic, Spomenka; Lohmeier-Vogel, Elke M.

2016-01-01

The laboratory protocol presented here takes about 3 hours to perform and investigates protein and lipid interactions. Students first purify His6-tagged human apolipoprotein A-I (apoA-I) with Ni-NTA affinity resin in a simple batch protocol and prepare multilamellar vesicles (MLV) from pre-dried phospholipid films. When apoA-I is added to the MLV,…

The Australian radiation protection and nuclear safety agency megavoltage photon thermoluminescence dosimetry postal audit service 2007-2010.

PubMed

Oliver, C P; Butler, D J; Webb, D V

2012-03-01

The Australian radiation protection and nuclear safety agency (ARPANSA) has continuously provided a level 1 mailed thermoluminescence dosimetry audit service for megavoltage photons since 2007. The purpose of the audit is to provide an independent verification of the reference dose output of a radiotherapy linear accelerator in a clinical environment. Photon beam quality measurements can also be made as part of the audit in addition to the output measurements. The results of all audits performed between 2007 and 2010 are presented. The average of all reference beam output measurements calculated as a clinically stated dose divided by an ARPANSA measured dose is 0.9993. The results of all beam quality measurements calculated as a clinically stated quality divided by an ARPANSA measured quality is 1.0087. Since 2011 the provision of all auditing services has been transferred from the Ionizing Radiation Standards section to the Australian Clinical Dosimetry Service (ACDS) which is currently housed within ARPANSA.

External Quality Assessment Scheme for reference laboratories - review of 8 years' experience.

PubMed

Kessler, Anja; Siekmann, Lothar; Weykamp, Cas; Geilenkeuser, Wolf Jochen; Dreazen, Orna; Middle, Jonathan; Schumann, Gerhard

2013-05-01

We describe an External Quality Assessment Scheme (EQAS) intended for reference (calibration) laboratories in laboratory medicine and supervised by the Scientific Division of the International Federation of Clinical Chemistry and Laboratory Medicine and the responsible Committee on Traceability in Laboratory Medicine. The official EQAS website, RELA (www.dgkl-rfb.de:81), is open to interested parties. Information on all requirements for participation and results of surveys are published annually. As an additional feature, the identity of every participant in relation to the respective results is disclosed. The results of various groups of measurands (metabolites and substrates, enzymes, electrolytes, glycated hemoglobins, proteins, hormones, thyroid hormones, therapeutic drugs) are discussed in detail. The RELA system supports reference measurement laboratories preparing for accreditation according to ISO 17025 and ISO 15195. Participation in a scheme such as RELA is one of the requirements for listing of the services of a calibration laboratory by the Joint Committee on Traceability in Laboratory Medicine.

Design Considerations of a Compounded Sterile Preparations Course

PubMed Central

Petraglia, Christine; Mattison, Melissa J.

2016-01-01

Objective. To design a comprehensive learning and assessment environment for the practical application of compounded sterile preparations using a constructivist approach. Design. Compounded Sterile Preparations Laboratory is a required 1-credit course that builds upon the themes of training aseptic technique typically used in health system settings and threads application of concepts from other courses in the curriculum. Students used critical-thinking skills to devise appropriate strategies to compound sterile preparations. Assessment. Aseptic technique skills were assessed with objective, structured, checklist-based rubrics. Most students successfully completed practical assessments using appropriate technique (mean assessment grade=83.2%). Almost all students passed the practical media fill (98%) and gloved fingertip sampling (86%) tests on the first attempt; all passed on the second attempt. Conclusion. Employing a constructivist scaffold approach to teaching proper hygiene and aseptic technique prepared students to pass media fill and gloved fingertip tests and to perform well on practical compounding assessments. PMID:26941438

Extension of laboratory-measured soil spectra to field conditions

NASA Technical Reports Server (NTRS)

Stoner, E. R.; Baumgardner, M. F.; Weismiller, R. A.; Biehl, L. L.; Robinson, B. F.

1982-01-01

Spectral responses of two glaciated soils, Chalmers silty clay loam and Fincastle silt loam, formed under prairie grass and forest vegetation, respectively, were measured in the laboratory under controlled moisture equilibria using an Exotech Model 20C spectroradiometer to obtain spectral data in the laboratory under artificial illumination. The same spectroradiometer was used outdoors under solar illumination to obtain spectral response from dry and moistened field plots with and without corn residue cover, representing the two different soils. Results indicate that laboratory-measured spectra of moist soil are directly proportional to the spectral response of that same field-measured moist bare soil over the 0.52 micrometer to 1.75 micrometer wavelength range. The magnitudes of difference in spectral response between identically treated Chalmers and Fincastle soils are greatest in the 0.6 micrometers to 0.8 micrometer transition region between the visible and near infrared, regardless of field condition or laboratory preparation studied.

A numerical cloud model for the support of laboratory experimentation

NASA Technical Reports Server (NTRS)

Hagen, D. E.

1979-01-01

A numerical cloud model is presented which can describe the evolution of a cloud starting from moist aerosol-laden air through the diffusional growth regime. The model is designed for the direct support of cloud chamber laboratory experimentation, i.e., experiment preparation, real-time control and data analysis. In the model the thermodynamics is uncoupled from the droplet growth processes. Analytic solutions for the cloud droplet growth equations are developed which can be applied in most laboratory situations. The model is applied to a variety of representative experiments.

Analysis of laboratory compaction methods of roller compacted concrete

NASA Astrophysics Data System (ADS)

Trtík, Tomáš; Chylík, Roman; Bílý, Petr; Fládr, Josef

2017-09-01

Roller-Compacted Concrete (RCC) is an ordinary concrete poured and compacted with machines typically used for laying of asphalt road layers. One of the problems connected with this technology is preparation of representative samples in the laboratory. The aim of this work was to analyse two methods of preparation of RCC laboratory samples with bulk density as the comparative parameter. The first method used dynamic compaction by pneumatic hammer. The second method of compaction had a static character. The specimens were loaded by precisely defined force in laboratory loading machine to create the same conditions as during static rolling (in the Czech Republic, only static rolling is commonly used). Bulk densities obtained by the two compaction methods were compared with core drills extracted from real RCC structure. The results have shown that the samples produced by pneumatic hammer tend to overestimate the bulk density of the material. For both compaction methods, immediate bearing index test was performed to verify the quality of compaction. A fundamental difference between static and dynamic compaction was identified. In static compaction, initial resistance to penetration of the mandrel was higher, after exceeding certain limit the resistance was constant. This means that the samples were well compacted just on the surface. Specimens made by pneumatic hammer actively resisted throughout the test, the whole volume was uniformly compacted.

[Establishment of optimal conditions at laboratory and pilot plant levels for the preparation of a protein isolated from Lupinus mutabilis].

PubMed

Rodríguez Pacheco, T; Aliaga, T; Schoeneberger, H; Gross, R

1981-12-01

Laboratory conditions were first investigated to determine are optimum processing parameters for the preparation of a protein isolate from the ground, defatted, commercial flakes of Lupinus mutabilis. The extraction variables were: pH (2-10); solvent to lupine ratio (5:1 to 40:1); temperature (28 degrees C - 60 degrees C) and time (10-50 min). The isoelectric point of the lupine protein was found to be pH 4.5 with a protein solubility higher than 80% above pH 8.0. Using 70-100 mesh, ground defatted flakes, and extracting at pH 8.7 for 60 min, a protein isolate was obtained on acidification to pH 4.5 which was 99.8 protein (dry basis), compared to 55.25% protein for the original material. This protein isolate represented 32% of the initial material and 57.6% of the initial nitrogen. When making pilot plant assays we found that the yield of protein isolate decreased to 20.4% of the original material and 36.4% of the initial nitrogen. The protein efficiency ratio for the protein isolate was 2.15 when supplemented with methionine, and had a digestibility of 89.33

To What Extent Does A-Level Physics Prepare Students for Undergraduate Laboratory Work?

ERIC Educational Resources Information Center

Thompson, Alaric

2012-01-01

This paper is a summary of a small-scale research project carried out to investigate the transition from A-level to university physics, with a specific focus on practical or laboratory skills. A brief description of the methods used precedes the headline findings of the research. A non-evidential discussion of the possible reasons behind any…

A Unit Cell Laboratory Experiment: Marbles, Magnets, and Stacking Arrangements

ERIC Educational Resources Information Center

Collins, David C.

2011-01-01

An undergraduate first-semester general chemistry laboratory experiment introducing face-centered, body-centered, and simple cubic unit cells is presented. Emphasis is placed on the stacking arrangement of solid spheres used to produce a particular unit cell. Marbles and spherical magnets are employed to prepare each stacking arrangement. Packing…

Alternate method of source preparation for alpha spectrometry: No electrodeposition, no hydrofluoric acid

DOE PAGES

Kurosaki, Hiromu; Mueller, Rebecca J.; Lambert, Susan B.; ...

2016-07-15

An alternate method of preparing actinide alpha counting sources was developed in place of electrodeposition or lanthanide fluoride micro-precipitation. The method uses lanthanide hydroxide micro-precipitation to avoid the use of hazardous hydrofluoric acid. Lastly, it provides a quicker, simpler, and safer way of preparing actinide alpha counting sources in routine, production-type laboratories that process many samples daily.

Thermoluminescent dosimeters (TLD) quality assurance network in the Czech Republic.

PubMed

Kroutilķková, Daniela; Novotný, Josef; Judas, Libor

2003-02-01

The Czech thermoluminescent dosimeters (TLD) quality assurance network was established in 1997. Its aim is to pursue a regular independent quality audit in Czech radiotherapy centres and to support state supervision. The audit is realised via mailed TL dosimetry. The TLD system consists of encapsulated LiF:Mg,Ti powder (type MT-N) read with Harshaw manual reader model 4000. Basic mode of the TLD audit covers measurements under reference conditions, specifically beam calibration checks for all clinically used photon and electron beams. Advanced mode consists of measurements under both reference and non-reference conditions using a solid multipurpose phantom ('Leuven phantom') for photon beams. The radiotherapy centres are instructed to deliver to the TLD on central beam axis absorbed dose of 2 Gy calculated with their treatment planning system for a particular treatment set-up. The TLD measured doses are compared with the calculated ones. Deviations of +/-3% are considered acceptable for both basic and advanced mode of the audit. There are 34 radiotherapy centres in the Czech Republic. They undergo the basic mode of the TLD audit regularly every 2 years. If a centre shows a deviation outside the acceptance level, it is audited more often. Presently, most of the checked beams comply with the acceptance level. The advanced TLD audit has been implemented as a pilot study for the present. The results were mostly within the acceptance limit for the measurements on-axis, whereas for off-axis points they fell beyond the limit more frequently, especially for set-ups with inhomogeneities, oblique incidence and wedges. The results prove the importance of the national TLD quality assurance network. It has contributed to the improvement of clinical dosimetry in the Czech Republic. In addition, it helps the regulatory authority to monitor effectively and regularly radiotherapy centres.

Screening for Saponins Using the Blood Hemolysis Test. An Undergraduate Laboratory Experiment.

ERIC Educational Resources Information Center

Sotheeswaran, Subramaniam

1988-01-01

Describes an experiment for undergraduate chemistry laboratories involving a chemical found in plants and some sea animals. Discusses collection and identification of material, a hemolysis test, preparation of blood-coated agar plates, and application of samples. (CW)

Very sensitive α-Al2O3:C polycrystals for thermoluminescent dosimetry.

PubMed

Fontainha, Críssia Carem Paiva; Alves, Neriene; Ferraz, Wilmar Barbosa; de Faria, Luiz Oliveira

2018-05-07

New materials have been widely investigated for ionizing radiation dosimetry for medical procedures. Carbon-doped alumina (α-Al 2 O 3 :C) have been reported to be excellent thermoluminescent (TL) and optically stimulated luminescence (OSL) radiation dosimeters. In the present study, we have synthetized nano and micro-sized α-Al 2 O 3 :C polycrystals, doped with different percentages of carbon atoms aiming to compare their efficiency as TL dosimeters. The dosimetric characteristics for X ray and gamma fields were investigated. Samples doped with different amounts of carbon atoms were sintered under different atmosphere conditions, at temperatures ranging from 1300 °C to 1750 °C. Among the investigated samples, the micro-sized alumina doped with 0.01% of carbon and sintered at 1700 °C under reducing atmosphere, has presented a very high TL output. The main TL peak is centered at 250 °C and has a linear behavior with photon dose in the dose range of 0.02-to-5000 mGy, with correlation coefficient very close to one (0.99991). Samples produced by using nanosized alumina have shown much lower TL output when compared to the samples with microsized alumina. The micro-sized alumina obtained by the methodology used in this work is a suitable candidate to be explored for application in X and Gamma radiation dosimetry. Copyright © 2018. Published by Elsevier Ltd.

Photoluminescence and thermoluminescence properties of Tb{sup 3+} doped K{sub 3}Gd(PO{sub 4}){sub 2} nanophosphor

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

Gupta, Palvi; Bedyal, A.K.; Kumar, Vinay, E-mail: vinaykdhiman@yahoo.com

2014-12-15

Energy level diagram of Tb{sup 3+} ion in the K{sub 3}Gd(PO{sub 4}){sub 2} host lattice. - Highlights: • First time, a detailed TL and PL study on undoped and Tb{sup 3+} doped K{sub 3}Gd(PO{sub 4}){sub 2} nanophosphor. • Combustion method was employed to synthesize the Tb{sup 3+} doped K{sub 3}Gd(PO{sub 4}){sub 2} nanophosphor. • Mechanism of excitation and emission in undoped and Tb{sup 3+} doped K{sub 3}Gd(PO{sub 4}){sub 2} nanophosphor was given. - Abstract: Tb{sup 3+} doped nanoparticulate K{sub 3}Gd(PO{sub 4}){sub 2} phosphor was prepared by combustion method using urea as a fuel. The structure, optical and luminescent properties ofmore » the phosphor were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and thermoluminescence (TL) spectroscopy. In undoped K{sub 3}Gd(PO{sub 4}){sub 2}, the excitation and emission peaks at 273 nm and 323 nm belongs to the {sup 8}S{sub 7/2} → {sup 6}I{sub J(J=7/2)} and {sup 6}P{sub J(J=7/2)} → {sup 8} S{sub 7/2} transitions of Gd{sup 3+} while green emission was observed in the Tb{sup 3+} doped K{sub 3}Gd(PO{sub 4}){sub 2}. TL study was carried out after exposing the samples to γ-radiations (0.1–5 kGy) in the K{sub 3}Gd(PO{sub 4}){sub 2}:Tb{sup 3+} (1.5 mol%). The calculated kinetic parameters were compared with different methods. The band gap of the phosphor was estimated as 5.80 eV. The green shade of the Tb{sup 3+} ion with the CIE coordinates (x, y) as (0.29, 0.54) was in good agreement with the well known green phosphors.« less

Studies on mass attenuation coefficient, effective atomic number and electron density of some thermoluminescent dosimetric compounds

NASA Astrophysics Data System (ADS)

Önder, P.; Turşucu, A.; Demir, D.; Gürol, A.

2012-12-01

Mass attenuation coefficient, μm , effective atomic number, Zeff, and effective electron density, Nel, were determined experimentally and theoretically for some thermoluminescent dosimetric (TLD) compounds such as MgSO4, CdSO4, Al2O3, Mg2SiO4, ZnSO4, CaSO4, CaF2, NaSO4, Na4P2O7, Ca5F(PO4)3, SiO2, CaCO3 and BaSO4 at 8.04, 8.91, 13.37, 14.97, 17.44, 19.63, 22.10, 24.90, 30.82, 32.06, 35.40, 36.39, 37.26, 43.74, 44.48, 50.38, 51.70, 53.16, 80.99, 276.40, 302.85, 356.01, 383.85 and 661.66 keV photon energies by using an HPGe detector with a resolution of 182 eV at 5.9 keV. The theoretical mass attenuation coefficients were estimated using mixture rule. The calculated values were compared with the experimental values for all compounds. Good agreement has been observed between experimental and theoretical values within experimental uncertainties.

100 MeV swift Si{sup 7+} ion induced thermoluminescence studies of nanocrystalline erbium doped ZrO{sub 2}

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

Lokesha, H. S.; Nagabhushana, K. R., E-mail: bhushankr@gmail.com; Singh, Fouran

2015-06-24

Pure and erbium (1mol%) doped nanocrystalline ZrO{sub 2} is synthesized by combustion technique. Thermoluminescence (TL) properties ZrO{sub 2}pellets annealed at 873 K and irradiated by 100 MeV swift Si{sup 7+} ion for various fluence are recorded. The evolution crystalline structure and crystallite size are done using by XRD data. Two TL glow curves, a well resolved one peak at ∼420 K and an unresolved with peak at ∼598 K are observed. TL intensity increases up to 3×10{sup 12} ions cm{sup −2} beyond which the TL intensity decreases. The glow peak shape method is used to calculate the TL trap parameter and discussed in thismore » paper.« less

Standards of teeth preparations for anterior resin bonded all-ceramic crowns in private dental practice in Jordan

PubMed Central

AL-DWAIRI, Ziad Nawaf; AL-HIYASAT, Ahmad Saleh; ABOUD, Haitham

2011-01-01

Objectives To investigate if general dental practitioners (GDPs) in private practice in Jordan follow universal guidelines for preparation of anterior teeth for resin bonded all-ceramic crowns (RBCs). Material and Methods A sample (n=100) of laboratory models containing 208 tooth preparations for IPS Empress and In Ceram, featuring work from different GDPs, was obtained from 8 commercial dental laboratories. Aspects of preparations were quantified and compared with accepted criteria defined following a review of the literature and recommendations of the manufactures' guidelines. Results Subgingival margins on the buccal aspect were noticed in 36% of the preparations, 54% demonstrated overpreparation with a tendency to overprepare the teeth on the mesiodistal plane more than buccolingual plane. Twenty percent of samples presented a shoulder finish line while a chamfer margin design was noticed in 39%. Twenty-nine percent and 12% of samples had either a feathered or no clear margin design respectively. Incisal under preparation was observed in 18% of dies of each type. Only 17% of all preparations were found to follow the recommended anatomical labial preparations while 29% of the RBC preparations were found to have the recommended axial convergence angle. In total, 43% of preparations were found to have the recommended depth of the finish line. Conclusions It was found that relevant guidelines for RBC preparations were not being fully adhered to in private practice in Jordan. PMID:21710098

Flake storage effects on properties of laboratory-made flakeboards

Treesearch

C. G. Carll

1998-01-01

Aspen (Populus gradidentata) and loblolly pine (Pinus taeda) flakes were prepared with tangential-grain and radial-grain faces on a laboratory disk flaker. These were gently dried in a steam-heated rotary drum dryer. Approximately 1 week after drying, surface wettability was measured on a large sample of flakes using an aqueous dye solution. Three replicate boards of...

Theme-Based Bidisciplinary Chemistry Laboratory Modules

NASA Astrophysics Data System (ADS)

Leber, Phyllis A.; Szczerbicki, Sandra K.

1996-12-01

, it will reinforce an understanding of the scientific method by allowing students to propose testable hypotheses based on previous work, and it will generate a large body of quantitative data that can be used to illustrate the fundamentals of data analysis, including statistical measures of uncertainty. We have already developed several "Environmental Chemistry" modules for general chemistry, including monitoring for orthophosphate and nitrate concentrations in water using colorimetric analyses and assaying for gasoline contamination in water and soil samples using GC-MS. Another module dealing with herbicide residues in soil is still being explored. However, we purposefully choose here to emphasize the two modules that are under development for implementation in the organic chemistry laboratory sequence. The first "Plant Assay" project focuses on fatty acid methyl esters (FAMEs) and involves three discrete phases: (i) synthesis and characterization of FAME standards, (ii) isolation of the fatty acids (as FAMEs) from a variety of different plant leaves that will be collected by BIO 110 students on field trips, and (iii) qualitative and quantitative analysis of the plant leaf extract for whole-leaf lipid composition. Acid-catalyzed Fischer esterification of carboxylic acids in methanol is a standard methodology for the preparation of methyl esters. A textbook procedure (1) for the synthesis of ethyl laurate has been employed, with good success, to prepare eight FAMEs in yields of ca. 70%. Conversion of leaf phospholipids to FAMEs proceeds readily via a transesterification reaction. Treatment of the whole leaf in a methanolic HCl solution for an hour at 80 °C (2) is sufficient after extraction in hexane to provide a suitable sample for GC-MS analysis. Preliminary results obtained with an HP GCD system indicate that GC-MS will afford highly reliable quantitative data on FAME lipid composition. Possible extensions of the project include using boron trifluoride in

Preparation, certification and interlaboratory analysis of workplace air filters spiked with high-fired beryllium oxide.

PubMed

Oatts, Thomas J; Hicks, Cheryl E; Adams, Amy R; Brisson, Michael J; Youmans-McDonald, Linda D; Hoover, Mark D; Ashley, Kevin

2012-02-01

Occupational sampling and analysis for multiple elements is generally approached using various approved methods from authoritative government sources such as the National Institute for Occupational Safety and Health (NIOSH), the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA), as well as consensus standards bodies such as ASTM International. The constituents of a sample can exist as unidentified compounds requiring sample preparation to be chosen appropriately, as in the case of beryllium in the form of beryllium oxide (BeO). An interlaboratory study was performed to collect analytical data from volunteer laboratories to examine the effectiveness of methods currently in use for preparation and analysis of samples containing calcined BeO powder. NIST SRM(®) 1877 high-fired BeO powder (1100 to 1200 °C calcining temperature; count median primary particle diameter 0.12 μm) was used to spike air filter media as a representative form of beryllium particulate matter present in workplace sampling that is known to be resistant to dissolution. The BeO powder standard reference material was gravimetrically prepared in a suspension and deposited onto 37 mm mixed cellulose ester air filters at five different levels between 0.5 μg and 25 μg of Be (as BeO). Sample sets consisting of five BeO-spiked filters (in duplicate) and two blank filters, for a total of twelve unique air filter samples per set, were submitted as blind samples to each of 27 participating laboratories. Participants were instructed to follow their current process for sample preparation and utilize their normal analytical methods for processing samples containing substances of this nature. Laboratories using more than one sample preparation and analysis method were provided with more than one sample set. Results from 34 data sets ultimately received from the 27 volunteer laboratories were subjected to applicable statistical analyses. The observed

Combinatorial Solid-Phase Synthesis of Aromatic Oligoamides: A Research-Based Laboratory Module for Undergraduate Organic Chemistry

ERIC Educational Resources Information Center

Fuller, Amelia A.

2016-01-01

A five-week, research-based experiment suitable for second-semester introductory organic laboratory students is described. Each student designs, prepares, and analyzes a combinatorial array of six aromatic oligoamides. Molecules are prepared on solid phase via a six-step synthetic sequence, and purities and identities are determined by analysis of…

Novel Sample-handling Approach for XRD Analysis with Minimal Sample Preparation

NASA Technical Reports Server (NTRS)

Sarrazin, P.; Chipera, S.; Bish, D.; Blake, D.; Feldman, S.; Vaniman, D.; Bryson, C.

2004-01-01

Sample preparation and sample handling are among the most critical operations associated with X-ray diffraction (XRD) analysis. These operations require attention in a laboratory environment, but they become a major constraint in the deployment of XRD instruments for robotic planetary exploration. We are developing a novel sample handling system that dramatically relaxes the constraints on sample preparation by allowing characterization of coarse-grained material that would normally be impossible to analyze with conventional powder-XRD techniques.

Outcomes of a Research-Driven Laboratory and Literature Course Designed to Enhance Undergraduate Contributions to Original Research

ERIC Educational Resources Information Center

Rasche, Madeline E.

2004-01-01

This work describes outcomes of a research-driven advanced microbiology laboratory and literature research course intended to enhance undergraduate preparation for and contributions to original research. The laboratory section was designed to teach fundamental biochemistry and molecular biology techniques in the context of an original research…

Test Rover Aids Preparations in California for Curiosity Rover on Mars

NASA Image and Video Library

2012-05-11

NASA Mars Science Laboratory mission team members ran mobility tests on the test rover called Scarecrow on sand dunes near Death Valley, Ca. in early May 2012 in preparation for operating the Curiosity rover, currently en route to Mars.

Synthesis and Characterization of Silver Nanoparticles for an Undergraduate Laboratory

ERIC Educational Resources Information Center

Orbaek, Alvin W.; McHale, Mary M.; Barron, Andrew R.

2015-01-01

The aim of this simple, quick, and safe laboratory exercise is to provide undergraduate students an introduction to nanotechnology using nanoparticle (NP) synthesis. Students are provided two procedures that allow for the synthesis of different yet controlled sizes of silver NPs. After preparing the NPs, the students perform UV-visible…

MEDICAL LABORATORY ASSISTANT, A SUGGESTED GUIDE FOR A TRAINING PROGRAM.

ERIC Educational Resources Information Center

Office of Education (DHEW), Washington, DC.

INFORMATION IS GIVEN TO ASSIST IN ORGANIZING AND ADMINISTERING A TRAINING PROGRAM FOR MEDICAL LABORATORY ASSISTANTS IN A VARIETY OF SETTINGS AND TO PROVIDE GUIDANCE IN ESTABLISHING NEW PROGRAMS AND IN EVALUATING EXISTING ONES. THE MATERIAL WAS PREPARED UNDER THE DIRECTION OF THE NATIONAL COMMITTEE FOR CAREERS IN MEDICAL TECHNOLOGY. PATHOLOGISTS…

Preparation and Use of Polish Mushroom Proficiency Testing Materials

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

Polkowska-Motrenko, Halina

2008-08-14

Mushroom reference materials have been prepared and characterized for the use in proficiency tests according to a procedure established within the frame of an IAEA Interregional Technical Cooperation Project. The materials were used for conducting the proficiency tests in Poland in 2005-2007. The results obtained by participating laboratories are presented and discussed.

Lower limits of detection in using carbon nanotubes as thermoluminescent dosimeters of beta radiation

NASA Astrophysics Data System (ADS)

Alanazi, Abdulaziz; Jurewicz, Izabela; Alalawi, Amani I.; Alyahyawi, Amjad; Alsubaie, Abdullah; Hinder, Steven; Bañuls-Ciscar, Jorge; Alkhorayef, Mohammed; Bradley, D. A.

2017-11-01

World-wide, on-going intensive research is being seen in adaptation of carbon nanotubes (CNTs) for a wide variety of applications, particular interest herein being in the thermoluminescent (TL) properties of CNTs and their sensitivity towards energetic radiations. Using beta radiation delivering dose levels of a few Gy it has been observed in previous study that strain and impurity defects in CNTs give rise to significant TL yields, providing an initial measure of the extent to which electron trapping centres exist in various qualities of CNT, from super-pure to raw. This in turn points to the possibility that there may be considerable advantage in using such media for radiation dosimetry applications, including for in vivo dosimetry. CNTs also have an effective atomic number similar to that of adipose tissue, making them suitable for soft tissue dosimetry. In present investigations various single-wall carbon nanotubes (SWCNT) samples in the form of buckypaper have been irradiated to doses in the range 35-1.3 Gy, use being made of a 90Sr beta source, the response of the CNTs buckypaper with dose showing a trend towards linearity. It is shown for present production methodology for buckypaper samples that the raw SWCNT buckypaper offer the greatest sensitivity, detecting doses down to some few tens of mGy.

Preparing to Respond: Joint Trauma Training Center and USAF Nursing Warskills Simulation Laboratory

DTIC Science & Technology

2003-06-01

and disability assessments. The timed tasks included time to oxy- gen administration, auscultation , pneumothorax rec- ognition and decompression...helicopter landing played while the nurse was trying to auscultate lung sounds. Finally, the laboratory was equipped with microphones and recording...are unable to auscultate a blood pressure. The following ECG strip was obtained. The immediate action is to A. Immerse the airman into an ice slurry to

Magnetoelectrets prepared by using temperature gradient method

NASA Astrophysics Data System (ADS)

Ojha, Pragya; Qureshi, M. S.; Malik, M. M.

2015-05-01

A novel Temperature Gradient method for preparation of magnetoelectret is proposed. Non uniform magnetic field and temperature gradient are expected to be the main cause for the formation of magnetoelectrets (MEs). Being bad conductors of heat, during their formation, there is a possibility for the existence of a temperature gradient along the dielectric electrode interface. In this condition, the motion of, molecules and charge carriers are dependent on Temperature Gradient in a preferred direction. To increase this temperature gradient on both sides of the sample novel method for the preparation of MEs is developed for the first time. For this method the special sample holders are designed in our laboratory. MEs are prepared in such a way that one surface is cooled and the other is heated, during the process. With the help of XRD analysis using Type-E orientation pattern and surface charge studies on magnetoelectrets, the two main causes Non uniform magnetic field and temperature gradient for the formation of magnetoelectrets (MEs), are authenticated experimentally.

Preparation and Characterization of Colloidal Silica Particles under Mild Conditions

ERIC Educational Resources Information Center

Neville, Frances; Zin, Azrinawati Mohd.; Jameson, Graeme J.; Wanless, Erica J.

2012-01-01

A microscale laboratory experiment for the preparation and characterization of silica particles at neutral pH and ambient temperature conditions is described. Students first employ experimental fabrication methods to make spherical submicrometer silica particles via the condensation of an alkoxysilane and polyethyleneimine, which act to catalyze…

Hadfield prepares to insert biological samples in the MELFI-1

NASA Image and Video Library

2013-01-07

View of Canadian Space Agency (CSA) Chris Hadfield,Expedition 34 Flight Engineer (FE),preparing to insert biological samples in the Minus Eighty Laboratory Freezer for International Space Station (ISS) - (MELFI-1),in the Japanese Experiment Module (JEM) Pressurized Module (JPM). Photo was taken during Expedition 34.

Carbonaceous Chondrite Thin Section Preparation

NASA Technical Reports Server (NTRS)

Harrington, R.; Righter, K.

2017-01-01

Carbonaceous chondrite meteorites have long posed a challenge for thin section makers. The variability in sample hardness among the different types, and sometimes within individual sections, creates the need for an adaptable approach at each step of the thin section making process. This poster will share some of the procedural adjustments that have proven to be successful at the NASA JSC Meteorite Thin Section Laboratory. These adjustments are modifications of preparation methods that have been in use for decades and therefore do not require investment in new technology or materials.

STS-65 Japanese Payload Specialist Mukai prepares for MAIL egress training

NASA Technical Reports Server (NTRS)

1994-01-01

STS-65 Japanese Payload Specialist Chiaki Mukai, wearing launch and entry suit (LES), prepares to participate in a training session in the Johnson Space Center's (JSC's) Mockup and Integration Laboratory (MAIL) Bldg 9NE. The entire STS-65 crew was on hand for egress training and countdown rehearsals. Representing Japan's National Space Development Agency (NASDA) Mukai will join six NASA astronauts for the International Microgravity Laboratory 2 (IML-2) mission aboard the Space Shuttle Columbia, Orbiter Vehicle (OV) 102, later this year.

Illinois Occupational Skill Standards: Agricultural Laboratory and Field Technician Cluster.

ERIC Educational Resources Information Center

Illinois Occupational Skill Standards and Credentialing Council, Carbondale.

These Illinois skill standards for the agricultural laboratory and field technician cluster are intended to serve as a guide to workforce preparation program providers as they define content for their programs and to employers as they establish the skills and standards necessary for job acquisition. They could also serve as a mechanism for…

Studies on the laboratory diagnosis of human filariasis: Preliminary communication

PubMed Central

Goldsmid, J. M.

1970-01-01

Five laboratory methods used for the recovery of microfilariae from the blood were compared for efficiency of recovery and time involved. The methods used were thin blood films, thick blood films, wet preparations, the Polyvidone technique, and the microhaematocrit technique. The last proved superior in both efficiency and saving time. Images PMID:5529998

An efficient field and laboratory workflow for plant phylotranscriptomic projects1

PubMed Central

Yang, Ya; Moore, Michael J.; Brockington, Samuel F.; Timoneda, Alfonso; Feng, Tao; Marx, Hannah E.; Walker, Joseph F.; Smith, Stephen A.

2017-01-01

Premise of the study: We describe a field and laboratory workflow developed for plant phylotranscriptomic projects that involves cryogenic tissue collection in the field, RNA extraction and quality control, and library preparation. We also make recommendations for sample curation. Methods and Results: A total of 216 frozen tissue samples of Caryophyllales and other angiosperm taxa were collected from the field or botanical gardens. RNA was extracted, stranded mRNA libraries were prepared, and libraries were sequenced on Illumina HiSeq platforms. These included difficult mucilaginous tissues such as those of Cactaceae and Droseraceae. Conclusions: Our workflow is not only cost effective (ca. $270 per sample, as of August 2016, from tissue to reads) and time efficient (less than 50 h for 10–12 samples including all laboratory work and sample curation), but also has proven robust for extraction of difficult samples such as tissues containing high levels of secondary compounds. PMID:28337391

Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans - joint RENEB and EURADOS inter-laboratory comparisons.

PubMed

Ainsbury, Elizabeth; Badie, Christophe; Barnard, Stephen; Manning, Grainne; Moquet, Jayne; Abend, Michael; Antunes, Ana Catarina; Barrios, Lleonard; Bassinet, Celine; Beinke, Christina; Bortolin, Emanuela; Bossin, Lily; Bricknell, Clare; Brzoska, Kamil; Buraczewska, Iwona; Castaño, Carlos Huertas; Čemusová, Zina; Christiansson, Maria; Cordero, Santiago Mateos; Cosler, Guillaume; Monaca, Sara Della; Desangles, François; Discher, Michael; Dominguez, Inmaculada; Doucha-Senf, Sven; Eakins, Jon; Fattibene, Paola; Filippi, Silvia; Frenzel, Monika; Georgieva, Dimka; Gregoire, Eric; Guogyte, Kamile; Hadjidekova, Valeria; Hadjiiska, Ljubomira; Hristova, Rositsa; Karakosta, Maria; Kis, Enikő; Kriehuber, Ralf; Lee, Jungil; Lloyd, David; Lumniczky, Katalin; Lyng, Fiona; Macaeva, Ellina; Majewski, Matthaeus; Vanda Martins, S; McKeever, Stephen W S; Meade, Aidan; Medipally, Dinesh; Meschini, Roberta; M'kacher, Radhia; Gil, Octávia Monteiro; Montero, Alegria; Moreno, Mercedes; Noditi, Mihaela; Oestreicher, Ursula; Oskamp, Dominik; Palitti, Fabrizio; Palma, Valentina; Pantelias, Gabriel; Pateux, Jerome; Patrono, Clarice; Pepe, Gaetano; Port, Matthias; Prieto, María Jesús; Quattrini, Maria Cristina; Quintens, Roel; Ricoul, Michelle; Roy, Laurence; Sabatier, Laure; Sebastià, Natividad; Sholom, Sergey; Sommer, Sylwester; Staynova, Albena; Strunz, Sonja; Terzoudi, Georgia; Testa, Antonella; Trompier, Francois; Valente, Marco; Hoey, Olivier Van; Veronese, Ivan; Wojcik, Andrzej; Woda, Clemens

2017-01-01

RENEB, 'Realising the European Network of Biodosimetry and Physical Retrospective Dosimetry,' is a network for research and emergency response mutual assistance in biodosimetry within the EU. Within this extremely active network, a number of new dosimetry methods have recently been proposed or developed. There is a requirement to test and/or validate these candidate techniques and inter-comparison exercises are a well-established method for such validation. The authors present details of inter-comparisons of four such new methods: dicentric chromosome analysis including telomere and centromere staining; the gene expression assay carried out in whole blood; Raman spectroscopy on blood lymphocytes, and detection of radiation-induced thermoluminescent signals in glass screens taken from mobile phones. In general the results show good agreement between the laboratories and methods within the expected levels of uncertainty, and thus demonstrate that there is a lot of potential for each of the candidate techniques. Further work is required before the new methods can be included within the suite of reliable dosimetry methods for use by RENEB partners and others in routine and emergency response scenarios.

ANITA (Advanced Network for Isotope and TArget laboratories) - The urgent need for a European target preparation network

NASA Astrophysics Data System (ADS)

Schumann, Dorothea; Sibbens, Goedele; Stolarz, Anna; Eberhardt, Klaus; Lommel, Bettina; Stodel, Christelle

2018-05-01

A wide number of research fields in the nuclear sector requires high-quality and well-characterized samples and targets. Currently, only a few laboratories own or have access to the equipment allowing fulfilling such demands. Coordination of activities and sharing resources is therefore mandatory to meet the increasing needs. This very urgent issue has now been addressed by six European target laboratories with an initiative called ANITA (Advanced Network for Isotope and TArget laboratories). The global aim of ANITA is to establish an overarching research infrastructure service for isotope and target production and develop a tight cooperation between the target laboratories in Europe in order to transfer the knowledge and improve the production techniques of well-characterized samples and targets. Moreover, the interaction of the target producers with the users shall be encouraged and intensified to deliver tailor-made targets best-suited to the envisaged experiments. For the realization of this ambitious goal, efforts within the European Commission and strong support by the target-using communities will be necessary. In particular, an appropriate funding instrument has to be found and applied, enabling ANITA to develop from an initiative employed by the interested parties to a real coordination platform.

Final report on EURAMET.QM-S10/1274: supplementary comparison of preparative capabilities for automotive gas mixtures

NASA Astrophysics Data System (ADS)

Val'ková, M.; Ďurišová, Z.; Szilágyi, Z. N.; Büki, T.; Fükű, J.

2016-01-01

This bilateral supplementary preparative comparison involves standard gas mixtures of automotive gas containing carbon monoxide, carbon dioxide and propane in nitrogen. Two laboratories (SMU, Slovakia and MKEH, Hungary) participated in this supplementary comparison. SMU was the coordinating laboratory, responsible for collecting and reporting measurement results. The participants have established facilities for automotive gas gravimetric preparation and analysis. The agreement of the results in this supplementary comparison is good. All the results with their reported uncertainties are in agreement with the reference values for the participants. SMU participated and obtained good results in the previous preparative comparison organised within EURAMET in this field. Both laboratories have existing claims for their Calibration and Measurement Capabilities (CMCs) for automotive gas mixtures. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The autonomic laboratory

NASA Technical Reports Server (NTRS)

Low, P. A.; Opfer-Gehrking, T. L.

1999-01-01

The autonomic nervous system can now be studied quantitatively, noninvasively, and reproducibly in a clinical autonomic laboratory. The approach at the Mayo Clinic is to study the postganglionic sympathetic nerve fibers of peripheral nerve (using the quantitative sudomotor axon reflex test [QSART]), the parasympathetic nerves to the heart (cardiovagal tests), and the regulation of blood pressure by the baroreflexes (adrenergic tests). Patient preparation is extremely important, since the state of the patient influences the results of autonomic function tests. The autonomic technologist in this evolving field needs to have a solid core of knowledge of autonomic physiology and autonomic function tests, followed by training in the performance of these tests in a standardized fashion. The range and utilization of tests of autonomic function will likely continue to evolve.

Lawrence Berkeley Laboratory Institutional Plan, FY 1993--1998

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

Chew, Joseph T.; Stroh, Suzanne C.; Maio, Linda R.

1992-10-01

The FY 1993--1998 Institutional Plan provides an overview of the Lawrence Berkeley Laboratory mission, strategic plan, scientific initiatives, research programs, environment and safety program plans, educational and technology transfer efforts, human resources, and facilities needs. The Strategic Plan section identifies long-range conditions that can influence the Laboratory, potential research trends, and several management implications. The Initiatives section identifies potential new research programs that represent major long-term opportunities for the Laboratory and the resources required for their implementation. The Scientific and Technical Programs section summarizes current programs and potential changes in research program activity. The Environment, Safety, and Health section describesmore » the management systems and programs underway at the Laboratory to protect the environment, the public, and the employees. The Technology Transfer and Education programs section describes current and planned programs to enhance the nation`s scientific literacy and human infrastructure and to improve economic competitiveness. The Human Resources section identifies LBL staff composition and development programs. The section on Site and Facilities discusses resources required to sustain and improve the physical plant and its equipment. The Resource Projections are estimates of required budgetary authority for the Laboratory`s ongoing research programs. The plan is an institutional management report for integration with the Department of Energy`s strategic planning activities that is developed through an annual planning process. The plan identifies technical and administrative directions in the context of the National Energy Strategy and the Department of Energy`s program planning initiatives. Preparation of the plan is coordinated by the Office for Planning and Development from information contributed by the Laboratory`s scientific and support divisions.« less

The ATLAS project: The effects of a constructionist digital laboratory project on undergraduate laboratory performance.

PubMed

Shoepe, Todd C; Cavedon, Dana K; Derian, Joseph M; Levy, Celine S; Morales, Amy

2015-01-01

Anatomical education is a dynamic field where developments in the implementation of constructive, situated-learning show promise in improving student achievement. The purpose of this study was to examine the effectiveness of an individualized, technology heavy project in promoting student performance in a combined anatomy and physiology laboratory course. Mixed-methods research was used to compare two cohorts of anatomy laboratories separated by the adoption of a new laboratory atlas project, which were defined as preceding (PRE) and following the adoption of the Anatomical Teaching and Learning Assessment Study (ATLAS; POST). The ATLAS project required the creation of a student-generated, photographic atlas via acquisition of specimen images taken with tablet technology and digital microscope cameras throughout the semester. Images were transferred to laptops, digitally labeled and photo edited weekly, and compiled into a digital book using Internet publishing freeware for final project submission. An analysis of covariance confirmed that student final examination scores were improved (P < 0.05) following the implementation of the laboratory atlas project (PRE, n = 75; POST, n = 90; means ± SE; 74.9 ± 0.9 versus 78.1 ± 0.8, respectively) after controlling for cumulative student grade point average. Analysis of questionnaires collected (n = 68) from the post group suggested students identified with atlas objectives, appreciated the comprehensive value in final examination preparation, and the constructionism involved, but recommended alterations in assignment logistics and the format of the final version. Constructionist, comprehensive term-projects utilizing student-preferred technologies could be used to improve performance toward student learning outcomes. © 2014 American Association of Anatomists.

Improvement in the performance of external quality assessment in Korean HIV clinical laboratories using unrecalcified human plasma.

PubMed

Wang, Jin-Sook; Kee, Mee-Kyung; Choi, Byeong-Sun; Kim, Chan-Wha; Kim, Hyon-Suk; Kim, Sung Soon

2012-01-01

The external quality assessment schemes (EQAS) organizer provides a suitable program to monitor and improve the quality of human immunodeficiency virus (HIV) testing laboratories with EQAS panels prepared under various conditions. The aim of the current study was to investigate the effects of human plasma samples on the EQAS results of HIV obtained from hospital-based clinical laboratories. From 2007 to 2009, HIV EQAS panels consisted of four to six samples that consisted of undiluted positive and negative samples and were provided to laboratories twice per year. Up until the first half EQAS in 2008, EQAS panel materials were obtained by converting acid citrate dextrose treated plasma to serum via chemical treatment with CaCl2. Beginning with the second EQAS in 2008, all materials were prepared without the defibrination process. Approximately 300 HIV clinical laboratories participated in this program. The overall performance of clinical laboratories was shown to be improved when using unrecalcified plasma panels compared with recalcified panels. Significant differences were observed in EIA analyses of plasma for both positive (p<0.001) and negative (p<0.001) samples between the recalcified and unrecalcified groups. Our finding suggested that defibrination status of EQAS panels might affect the results of anti-HIV EQAS of Korean HIV testing laboratories.

The U.S. Laboratory module arrives at KSC

NASA Technical Reports Server (NTRS)

1998-01-01

NASA's 'Super Guppy' aircraft arrives in KSC air space escorted by two T-38 aircraft after leaving Marshall Space Flight Center in Huntsville, Ala. The whale-like airplane carries the U.S. Laboratory module, considered the centerpiece of the International Space Station. The module will undergo final pre- launch preparations at KSC's Space Station Processing Facility. Scheduled for launch aboard the Shuttle Endeavour on mission STS- 98, the laboratory comprises three cylindrical sections with two end cones. Each end-cone contains a hatch opening for entering and exiting the lab. The lab will provide a shirtsleeve environment for research in such areas as life science, microgravity science, Earth science and space science. Designated Flight 5A, this mission is targeted for launch in early 2000.

Designing Polymerase Chain Reaction (PCR) Primer Multiplexes in the Forensic Laboratory

ERIC Educational Resources Information Center

Elkins, Kelly M.

2011-01-01

The polymerase chain reaction (PCR) is a common experiment in upper-level undergraduate biochemistry, molecular biology, and forensic laboratory courses as reagents and thermocyclers have become more affordable for institutions. Typically, instructors design PCR primers to amplify the region of interest and the students prepare their samples for…

1983 international intercomparison of nuclear accident dosimetry systems at Oak Ridge National Laboratory

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

Swaja, R.E.; Greene, R.T.; Sims, C.S.

1985-04-01

An international intercomparison of nuclear accident dosimetry systems was conducted during September 12-16, 1983, at Oak Ridge National Laboratory (ORNL) using the Health Physics Research Reactor operated in the pulse mode to simulate criticality accidents. This study marked the twentieth in a series of annual accident dosimetry intercomparisons conducted at ORNL. Participants from ten organizations attended this intercomparison and measured neutron and gamma doses at area monitoring stations and on phantoms for three different shield conditions. Results of this study indicate that foil activation techniques are the most popular and accurate method of determining accident-level neutron doses at area monitoringmore » stations. For personnel monitoring, foil activation, blood sodium activation, and thermoluminescent (TL) methods are all capable of providing accurate dose estimates in a variety of radiation fields. All participants in this study used TLD's to determine gamma doses with very good results on the average. Chemical dosemeters were also shown to be capable of yielding accurate estimates of total neutron plus gamma doses in a variety of radiation fields. While 83% of all neutron measurements satisfied regulatory standards relative to reference values, only 39% of all gamma results satisfied corresponding guidelines for gamma measurements. These results indicate that continued improvement in accident dosimetry evaluation and measurement techniques is needed.« less

Survey of Clinical Laboratory Practices for 2015 Middle East Respiratory Syndrome Coronavirus Outbreak in the Republic of Korea.

PubMed

Lee, Mi-Kyung; Kim, Sinyoung; Kim, Mi-Na; Kweon, Oh Joo; Lim, Yong Kwan; Ki, Chang-Seok; Kim, Jae-Seok; Seong, Moon-Woo; Sung, Heungsup; Yong, Dongeun; Lee, Hyukmin; Choi, Jong-Rak; Kim, Jeong-Ho

2016-03-01

It is crucial to understand the current status of clinical laboratory practices for the largest outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infections in the Republic of Korea to be well prepared for future emerging infectious diseases. We conducted a survey of 49 clinical laboratories in medical institutions and referral medical laboratories. A short questionnaire to survey clinical laboratory practices relating to MERS-CoV diagnostic testing was sent by email to the directors and clinical pathologists in charge of the clinical laboratories performing MERS-CoV testing. The survey focused on testing volume, reporting of results, resources, and laboratory safety. A total of 40 clinical laboratories responded to the survey. A total of 27,009 MERS-CoV real-time reverse transcription PCR (rRT-PCR) tests were performed. Most of the specimens were sputum (73.5%). The median turnaround time (TAT) was 5.29 hr (first and third quartile, 4.11 and 7.48 hr) in 26 medical institutions. The median TAT of more than a half of the laboratories (57.7%) was less than 6 hr. Many laboratories were able to perform tests throughout the whole week. Laboratory biosafety preparedness included class II biosafety cabinets (100%); separated pre-PCR, PCR, and post-PCR rooms (88.6%); negative pressure pretreatment rooms (48.6%); and negative pressure sputum collection rooms (20.0%). Clinical laboratories were able to quickly expand their diagnostic capacity in response to the 2015 MERS-CoV outbreak. Our results show that clinical laboratories play an important role in the maintenance and enhancement of laboratory response in preparation for future emerging infections.

Survey of Clinical Laboratory Practices for 2015 Middle East Respiratory Syndrome Coronavirus Outbreak in the Republic of Korea

PubMed Central

Lee, Mi-Kyung; Kim, Sinyoung; Kim, Mi-Na; Kweon, Oh Joo; Lim, Yong Kwan; Ki, Chang-Seok; Kim, Jae-Seok; Seong, Moon-Woo; Sung, Heungsup; Yong, Dongeun; Lee, Hyukmin; Choi, Jong-Rak

2016-01-01

Background It is crucial to understand the current status of clinical laboratory practices for the largest outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infections in the Republic of Korea to be well prepared for future emerging infectious diseases. Methods We conducted a survey of 49 clinical laboratories in medical institutions and referral medical laboratories. A short questionnaire to survey clinical laboratory practices relating to MERS-CoV diagnostic testing was sent by email to the directors and clinical pathologists in charge of the clinical laboratories performing MERS-CoV testing. The survey focused on testing volume, reporting of results, resources, and laboratory safety. Results A total of 40 clinical laboratories responded to the survey. A total of 27,009 MERS-CoV real-time reverse transcription PCR (rRT-PCR) tests were performed. Most of the specimens were sputum (73.5%). The median turnaround time (TAT) was 5.29 hr (first and third quartile, 4.11 and 7.48 hr) in 26 medical institutions. The median TAT of more than a half of the laboratories (57.7%) was less than 6 hr. Many laboratories were able to perform tests throughout the whole week. Laboratory biosafety preparedness included class II biosafety cabinets (100%); separated pre-PCR, PCR, and post-PCR rooms (88.6%); negative pressure pretreatment rooms (48.6%); and negative pressure sputum collection rooms (20.0%). Conclusions Clinical laboratories were able to quickly expand their diagnostic capacity in response to the 2015 MERS-CoV outbreak. Our results show that clinical laboratories play an important role in the maintenance and enhancement of laboratory response in preparation for future emerging infections. PMID:26709263

Preparation of Semiconducting Materials in the Laboratory, Part 3: The One-Penny Photovoltaic Cell

ERIC Educational Resources Information Center

Ibanez, Jorge G.; Finck-Pastrana, Adolfo; Mugica-Barrera, Alejandra; Balderas-Hernandez, Patricia; Ibarguengoitia-Cervantes, Martha E.; Garcia-Pintor, Elizabeth; Hartasanchez-Frenk, Jose Miguel; Bonilla-Jaurez, Cesar E.; Maldonado-Cordero, Casandra; Struck-Garza, Adelwart; Suberbie-Rocha, Felipe

2011-01-01

Copper(I) oxide photoresponsive layers are prepared on copper surfaces (e.g., U.S. pre-1982 pennies) by simple thermal, chemical, and electrochemical procedures. An easily measurable photovoltage (up to 100 mV) is obtained in each case under visible light illumination. (Contains 2 figures.)

Astronaut Crippen prepares to join crew in training

NASA Image and Video Library

1984-09-04

41D-3186 (4 Sept 1984) --- Astronaut Robert L. Crippen, 41-G crew commander, prepares to join his six fellow crewmembers for some training in the mockup and integration laboratory at the Johnson Space Center. Astronaut David C. Leestma, 41-G mission specialist, left, will participate in a scheduled extravehicular activity (EVA) on the Challenger's next mission. Today's training is for launch phase procedures.

STS-58 crewmembers prepare for a training exercise

NASA Image and Video Library

1993-07-20

S93-38672 (20 July 1993) --- Wearing training versions of the partial pressure launch and entry garment, the STS-58 crewmembers prepare for a training exercise. After being briefed by astronaut John E. Blaha (right), mission commander, the group rehearsed contingency evacuation procedures. Most of the training session took part in the crew compartment and full fuselage trainers in the Space Shuttle mockup and integration laboratory.

DESIGN OF A SURFACTANT REMEDIATION FIELD DEMONSTRATION BASED ON LABORATORY AND MODELINE STUDIES

EPA Science Inventory

Surfactant-enhanced subsurface remediation is being evaluated as an innovative technology for expediting ground-water remediation. This paper reports on laboratory and modeling studies conducted in preparation for a pilot-scale field test of surfactant-enhanced subsurface remedia...

Thermoluminescent dosimetry in rotary-dual technique of the total skin electron irradiation.

PubMed

Piotrowski, T; Fundowicz, D; Pawlaczyk, M; Malicki, J

2003-01-01

The aim of the study was to discuss the results of thermoluminescent dosimetry (TLD) in rotary-dual technique of the total skin electron irradiation (TSEI RD), to confirm beam calibration and monitor unit calculations and to provide data for making clinical decisions. Between May 2001 and April 2002, in 3 cases of mycosis fungoides, 736 dosimetric checks were performed in 34 points at the skin. CaF2:MnTLD-400 cubes (1/8"x1/8"x0.015") were used for in vivo dosimetry. Doses were computed and analyzed for all locations. Percent of described dose and SD for the following localizations from 34 points were: anterior abdomen (reference point) 100+/-6%, upper back 100+/-8%, right calf 98+/-10%, left foot (mid dorsum) 97+/-8%, posterior neck 93+/-6%, right hand (mid dorsum) 78+/-10%, hand fingers 57+/-10%, top of right shoulder 56+/-14%, left groin 35+/-20%, perineum 22+/-17%. The correlations between patient's height and measured doses were sufficient for the following localizations: scalp (top rear), occiput, elbows, hand fingers and hands (mid dorsum). The correlations between obesity index and measured doses were sufficient for the following localizations: shoulders and lateral neck, groins, and perineum. Dosimetric checks at the reference point confirm that our beam calibration technique and monitor unit calculation are accurate. TLD shows that for some parts of the skin such as shoulder, hands and perineum boost fields were required. The correlations with obesity index and height for several sites suggest that boost fields must be customized for each patient.

D1-arginine257 mutants (R257E, K, and Q) of Chlamydomonas reinhardtii have a lowered QB redox potential: analysis of thermoluminescence and fluorescence measurements

PubMed Central

Rose, Stuart; Minagawa, Jun; Seufferheld, Manfredo; Padden, Sean; Svensson, Bengt; Kolling, Derrick R. J.; Crofts, Antony R.; Govindjee

2009-01-01

Arginine257 (R257), in the de-helix that caps the QB site of the D1 protein, has been shown by mutational studies to play a key role in the sensitivity of Photosystem II (PS II) to bicarbonate-reversible binding of the formate anion. In this article, the role of this residue has been further investigated through D1 mutations (R257E, R257Q, and R257K) in Chlamydomonas reinhardtii. We have investigated the activity of the QB site by studying differences from wild type on the steady-state turnover of PS II, as assayed through chlorophyll (Chl) a fluorescence yield decay after flash excitation. The effects of p-benzoquinone (BQ, which oxidizes reduced QB, QB−) and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU, which blocks electron flow from QA− to QB) were measured. The equilibrium constants of the two-electron gate were obtained through thermoluminescence measurements. The thermoluminescence properties were changed in the mutants, especially when observed after pretreatment with 100 μM BQ. A theoretical analysis of the thermoluminescence data, based mainly on the recombination pathways model of Rappaport et al. (2005), led to the conclusion that the free-energy difference for the recombination of QB− with S2 was reduced by 20–40 mV in the three mutants (D1-R257K, D1-R257Q, and D1-R257E); this was interpreted to be due to a lowering of the redox potential of QB/QB−. Further, since the recombination of QA− with S2 was unaffected, we suggest that no significant change in redox potential of QA/QA− occurred in these three mutants. The maximum variable Chl a fluorescence yield is lowered in the mutants, in the order R257K > R257Q > R257E, compared to wild type. Our analysis of the binary oscillations in Chl a fluorescence following pretreatment of cells with BQ showed that turnover of the QB site was relatively unaffected in the three mutants. The mutant D1-R257E had the lowest growth rate and steady-state activity and showed the weakest binary oscillations

Kontekst stratygraficzny zastosowania różnych odmian metody termoluminescencyjnej w datowaniu lessów z terenu Polski południowo-wschodniej i Ukrainy północno-zachodniej

NASA Astrophysics Data System (ADS)

Kusiak, Jarosław

2008-01-01

Loess profiles contain a complex but usually incomplete sequence of deposits. In order to chronologically organize deposit layers accessible in different exposures it is necessary to use absolute dating methods. The 14C, TL and OSL methods are widely used for dating of the Upper Pleistocene deposits whereas to older Pleistocene deposits only luminescence methods are applied. Some attempts are made to use the OSL method for dating of the deposits older than the Upper Pleistocene. However, the OSL ages seem to be consistently lower than the TL ages, and also considerably underestimated with reference to stratigraphic interpretation. This fact indicates that the TL method should be used above all. The possibility of TL dating of loesses is connected with their aeolian origin. The obtained TL age should correspond to geological time when mineral grains constituting deposit were exposed to sunlight before deposition. Such exactly condition is met in case of loess deposits. There are many variants of thermoluminescence method because different measuring procedures can be used. Depending on the used procedure, the TL ages obtained for the same sample can be considerably different. The manner of equivalent dose determination is decisive for the obtained TL ages. The factors influencing the value of equivalent dose are presented in this paper. The equivalent dose is determined by comparison of thermoluminescence measured for a given sample with thermoluminescence of the same sample after irradiation in laboratory with known doses of ionizing radiation. The following criteria should be taken into account: size of mineral grains, relation between thermoluminescence and heating temperature, way of reduction of unstable thermoluminescence, and the results of plateau test. The variant of thermoluminescence method used in the TL Laboratory of the Department of Physical Geography and Palaeogeography, Maria Curie-Skłodowska University in Lublin is as follows. The dose rate is

Thermoluminescent Mechanisms in Calcium Sulphate Doped with Dysprosium.

NASA Astrophysics Data System (ADS)

Matthews, Robert James

Thermoluminescent (TL) mechanisms in CaSO(,4):Dy caused by ionizing irradiation are investigated. Influences of the background impurities on the structure of the glow curve are determined and are correlated with known electron spin resonance (ESR) results. These are combined with fading studies that determine the TL process as bimolecular or monomolecular and the order of the kinetics involved. The TL emission spectrum is determined for all temperature regions of the TL emission to 400(DEGREES)C; optical absorption (OA) in the visible provides information on the valence state of the Dy ion. Photo stimulated transfer of TL (PTTL) helps determine the influence of traps deeper than 400(DEGREES)C, while studies of CaSO(,4):Dy in the scanning electron microscope (SEM) operated in the cathodoluminescent (CL) mode provide information on processes occurring during electron bombardment and on the distribution of Dy in CaSO(,4). The information from these studies is combined to form comprehensive models of the TL mechanisms responsible for the TL glow peaks.(,). The glow peak occurring between 130(DEGREES)C and 260(DEGREES)C, usually designated as the dosimetric peak, was determined to be the result of two primary processes. In the first mechanism, the SO(,3)('-) radical recombines with an oxygen interstitial (O(,i)('-)) associated with the Dy('3+) in charge compensation. The recombination energy is given up as TL. In the second mechanism, it is concluded that divalent Dy release electrons to the conduction band in a non-radiative process. The liberated electron recombines with a hole center at a remote SO(,4)(' -) site. The recombination energy is either transferred to trivalent Dy, which emits TL, or this energy causes the (SO(,4)('-))* to disassociate and form an SO(,3)(' -) and an O(,i)('-). These defects are thought to recombine at about 300(DEGREES)C. In the low temperature region (room temperature to 130(DEGREES)C), the monovalent cation, particularly Na('+) acting as

A Laboratory Study Investigating the Feasibility of Applying Calcite-Type Coatings to Segregated Ballast Tanks

DTIC Science & Technology

1981-08-01

A LABORATORY STUDY INVESTIGATIING THE FEASIBILITY OF APPLYING CALCITE -TYPE COATINGS TO SEGREGATED BALLAST TANKS AUGUST, 1981 Prepared by: Ocean City...Laboratory Study Investigating The Feasibility of Applying Calcite -Type Coatings to Segregated Ballast Tanks 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...Executive Summary List of Figures I. Conclusions II. Introduction III. Background-The Development and Use of Calcite -Type Coatings IV. Experimental

Preparation and stability of extemporaneous oral liquid formulations of oseltamivir using commercially available capsules.

PubMed

Winiarski, Aleksander P; Infeld, Martin H; Tscherne, Ronald; Bachynsky, Maria; Rucki, Richard; Nagano-Mate, Kathy

2007-01-01

To develop a simple, standardized method for the extemporaneous compounding of an oral liquid form of oseltamivir from commercially available Tamiflu 75 mg capsules (Roche Pharmaceuticals) and to determine the stability of oseltamivir in this preparation. Chemical and microbial stability study. Laboratory. None. Extemporaneous oral liquid formulations of oseltamivir (15 mg/mL) were prepared in Cherry Syrup (Humco) and Ora-Sweet SF (Paddock Laboratories) using methods consistent with current compounding practice in a pharmacy setting. Preparations were stored in amber glass and amber polyethyleneterephthalate bottles at 5 degrees C +/- 2 degrees C (41 degrees F +/- 4 degrees F) and 25 degrees C +/- 2 degrees C (77 degrees F +/- 4 degrees F) at 60% +/- 5% relative humidity (RH) for 35 days and 30 degrees C +/- 2 degrees C (86 degrees F +/- 4 degrees F) at 65% +/- 5% RH for 13 days. Samples were monitored for appearance, pH, assay, degradation products, and microbiologic stability. The Cherry Syrup preparation, in either bottle type, was stable for up to 35 days under refrigeration (5 degrees C) and up to 5 days at room temperature (25 degrees C). It was not stable when stored at 30 degrees C for 5 days. The Ora-Sweet SF preparation was stable for up to 35 days at 5 degrees C or 25 degrees C and for up to 13 days at 30 degrees C in either bottle type. Both preparations maintained microbiologic stability for 35 days. Both preparations are stable under the described conditions and may provide an option in situations where the marketed suspension is unavailable.

A Green Polymerization of Aspartic Acid for the Undergraduate Organic Laboratory

ERIC Educational Resources Information Center

Bennett, George D.

2005-01-01

The green polymerization of aspartic acid carried out during an organic-inorganic synthesis laboratory course for undergraduate students is described. The procedure is based on work by Donlar Corporation, a Peru, Illinois-based company that won a Green Chemistry Challenge Award in 1996 in the Small Business category for preparing thermal…

Gas Clathrate Hydrates Experiment for High School Projects and Undergraduate Laboratories

ERIC Educational Resources Information Center

Prado, Melissa P.; Pham, Annie; Ferazzi, Robert E.; Edwards, Kimberly; Janda, Kenneth C.

2007-01-01

We present a laboratory procedure, suitable for high school and undergraduate students, for preparing and studying propane clathrate hydrate. Because of their gas storage potential and large natural deposits, gas clathrate hydrates may have economic importance both as an energy source and a transportation medium. Similar to pure ice, the gas…

Rapid Methods for the Laboratory Identification of Pathogenic Microorganisms.

DTIC Science & Technology

1982-09-01

for the use of plant proteins, called lectins, in diagnostic microbiology. We studied lectin interactions with Staphylococcus, Legionella, Streptococcus ...commercial sources (BBL and Difco). Thethree Brucella species: suis abortus, and melitensis were also purchased from BBL and Difco. Lectins were obtained...that are killed by antibiotic treatment rather than formalin. Lee Laboratories in Georgia has offered to prepare these antigens for us according to our

Comparative study of six sequential spectrophotometric methods for quantification and separation of ribavirin, sofosbuvir and daclatasvir: An application on Laboratory prepared mixture, pharmaceutical preparations, spiked human urine, spiked human plasma, and dissolution test.

PubMed

Hassan, Wafaa S; Elmasry, Manal S; Elsayed, Heba M; Zidan, Dalia W

2018-09-05

In accordance with International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines, six novel, simple and precise sequential spectrophotometric methods were developed and validated for the simultaneous analysis of Ribavirin (RIB), Sofosbuvir (SOF), and Daclatasvir (DAC) in their mixture without prior separation steps. These drugs are described as co-administered for treatment of Hepatitis C virus (HCV). HCV is the cause of hepatitis C and some cancers such as liver cancer (hepatocellular carcinoma) and lymphomas in humans. These techniques consisted of several sequential steps using zero, ratio and/or derivative spectra. DAC was first determined through direct spectrophotometry at 313.7 nm without any interference of the other two drugs while RIB and SOF can be determined after ratio subtraction through five methods; Ratio difference spectrophotometric method, successive derivative ratio method, constant center, isoabsorptive method at 238.8 nm, and mean centering of the ratio spectra (MCR) at 224 nm and 258 nm for RIB and SOF, respectively. The calibration curve is linear over the concentration ranges of (6-42), (10-70) and (4-16) μg/mL for RIB, SOF, and DAC, respectively. This method was successfully applied to commercial pharmaceutical preparation of the drugs, spiked human urine, and spiked human plasma. The above methods are very simple methods that were developed for the simultaneous determination of binary and ternary mixtures and so enhance signal-to-noise ratio. The method has been successfully applied to the simultaneous analysis of RIB, SOF, and DAC in laboratory prepared mixtures. The obtained results are statistically compared with those obtained by the official or reported methods, showing no significant difference with respect to accuracy and precision at p = 0.05. Copyright © 2018 Elsevier B.V. All rights reserved.

Methodological considerations for implementation of lymphocyte subset analysis in a clinical reference laboratory.

PubMed

Muirhead, K A; Wallace, P K; Schmitt, T C; Frescatore, R L; Franco, J A; Horan, P K

1986-01-01

As the diagnostic utility of lymphocyte subset analysis has been recognized in the clinical research laboratory, a wide variety of reagents and cell preparation, staining and analysis methods have also been described. Methods that are perfectly suitable for analysis of smaller sample numbers in the biological or clinical research setting are not always appropriate and/or applicable in the setting of a high volume clinical reference laboratory. We describe here some of the specific considerations involved in choosing a method for flow cytometric analysis which minimizes sample preparation and data analysis time while maximizing sample stability, viability, and reproducibility. Monoclonal T- and B-cell reagents from three manufacturers were found to give equivalent results for a reference population of healthy individuals. This was true whether direct or indirect immunofluorescence staining was used and whether cells were prepared by Ficoll-Hypaque fractionation (FH) or by lysis of whole blood. When B cells were enumerated using a polyclonal anti-immunoglobulin reagent, less cytophilic immunoglobulin staining was present after lysis than after FH preparation. However, both preparation methods required additional incubation at 37 degrees C to obtain results concordant with monoclonal B-cell reagents. Standard reagents were chosen on the basis of maximum positive/negative separation and the availability of appropriate negative controls. The effects of collection medium and storage conditions on sample stability and reproducibility of subset analysis were also assessed. Specimens collected in heparin and stored at room temperature in buffered medium gave reproducible results for 3 days after specimen collection, using either FH or lysis as the preparation method. General strategies for instrument optimization, quality control, and biohazard containment are also discussed.

The laboratory of the 1990s—Planning for total automation

PubMed Central

Brunner, Linda A.

1992-01-01

The analytical laboratory of the 1990s must be able to meet and accommodate the rapid evolution of modern-day technology. One such area is laboratory automation. Total automation may be seen as the coupling of computerized sample tracking, electronic documentation and data reduction with automated sample handling, preparation and analysis, resulting in a complete analytical procedure with minimal human involvement. Requirements may vary from one laboratory or facility to another, so the automation has to be flexible enough to cover a wide range of applications, and yet fit into specific niches depending on individual needs. Total automation must be planned for, well in advance, if the endeavour is to be a success. Space, laboratory layout, proper equipment, and the availability and access to necessary utilities must be taken into account. Adequate training and experience of the personnel working with the technology must also be ensured. In addition, responsibilities of installation, programming maintenance and operation have to be addressed. Proper time management and the efficient implementation and use of total automation are also crucial to successful operations. This paper provides insights into laboratory organization and requirements, as well as discussing the management issues that must be faced when automating laboratory procedures. PMID:18924925

Assessment and management of chemical exposure in the Mohs laboratory.

PubMed

Gunson, Todd H; Smith, Harvey R; Vinciullo, Carl

2011-01-01

The correct handling, storage, and disposal of chemicals used in the processing of tissue for Mohs micrographic surgery are essential. To identify the chemicals involved in the preparation of Mohs frozen sections and assess the associated occupational health risks. To quantify exposure levels of hazardous chemicals and ensure that they are minimized. A risk assessment form was completed for each chemical. Atmospheric sampling was performed at our previous laboratory for formaldehyde and volatile organic compounds. These data were used in the design of our new facility, where testing was repeated. Twenty-five chemicals were identified. Ten were classified as hazardous substances, 10 were flammable, six had specific disposal requirements, four were potential carcinogens, and three were potential teratogens. Formaldehyde readings at our previous laboratory were up to eight times the national exposure standard. Testing at the new laboratory produced levels well below the exposure standards. Chemical exposure within the Mohs laboratory can present a significant occupational hazard. Acutely toxic and potentially carcinogenic formaldehyde was found at high levels in a relatively standard laboratory configuration. A laboratory can be designed with a combination of physical environment and operational protocols that minimizes hazards and creates a safe working environment. © 2010 by the American Society for Dermatologic Surgery, Inc.

Using the TA to Prepare Graduate Students for Research and Employment

NASA Astrophysics Data System (ADS)

Heller, Kenneth

One of the most underused components of the physics graduate program is the time spent being a teaching assistant (TA). Often the TA duties consist of grading and trying to help undergraduates survive a physics course. How those duties are accomplished is left to each TA. The most common TA preparation, if it exists, has a narrow focus on the class being taught. Preparation consists of describing, or perhaps practicing, specific teaching skills and gaining familiarity with the equipment used in the laboratory portion of the class. Instead TAs can be integrated into the entire course in which they function so that they learn the course as a system. This means treating a course in the same way one approaches a research project with the TAs as members of the research team headed by a faculty advisor. TA preparation is broadened and support includes the management, teamwork, and communication skills necessary. This makes the TAs more efficient and effective teachers while explicitly connecting the TA experience to the ``soft'' skills they need in their own research careers whether in industry, national laboratories, or academia. This talk describes such a program, functioning for over 20 years at the University of Minnesota, that takes no more time than the usual TA but results in graduate students that are more satisfied with their TA experience, are better prepared to function in research groups, and provide a better classroom experience for their undergraduate students.

Thermoluminescence dosimetry applied to in vivo dose measurements for total body irradiation techniques.

PubMed

Duch, M A; Ginjaume, M; Chakkor, H; Ortega, X; Jornet, N; Ribas, M

1998-06-01

In total body irradiation (TBI) treatments in vivo dosimetry is recommended because it makes it possible to ensure the accuracy and quality control of dose delivery. The aim of this work is to set up an in vivo thermoluminescence dosimetry (TLD) system to measure the dose distribution during the TBI technique used prior to bone marrow transplant. Some technical problems due to the presence of lung shielding blocks are discussed. Irradiations were performed in the Hospital de la Santa Creu i Sant Pau by means of a Varian Clinac-1800 linear accelerator with 18 MV X-ray beams. Different TLD calibration experiments were set up to optimize in vivo dose assessment and to analyze the influence on dose measurement of shielding blocks. An algorithm to estimate midplane doses from entrance and exit doses is proposed and the estimated dose in critical organs is compared to internal dose measurements performed in an Alderson anthropomorphic phantom. The predictions of the dose algorithm, even in heterogeneous zones of the body such as the lungs, are in good agreement with the experimental results obtained with and without shielding blocks. The differences between measured and predicted values are in all cases lower than 2%. The TLD system described in this work has been proven to be appropriate for in vivo dosimetry in TBI irradiations. The described calibration experiments point out the difficulty of calibrating an in vivo dosimetry system when lung shielding blocks are used.

Chromatography in the detection and characterization of illegal pharmaceutical preparations.

PubMed

Deconinck, Eric; Sacré, Pierre-Yves; Courselle, Patricia; De Beer, Jacques O

2013-09-01

Counterfeit and illegal pharmaceutical products are an increasing worldwide problem and constitute a major challenge for analytical laboratories to detect and characterize them. Spectroscopic techniques such as infrared spectroscopy and Raman spectroscopy have always been the first methods of choice to detect counterfeits and illegal preparations, but due to the evolution in the seized products and the necessity of risk assessment, chromatographic methods are becoming more important in this domain. This review intends to give a general overview of the techniques described in literature to characterize counterfeit and illegal pharmaceutical preparations, focusing on the role of chromatographic techniques with different detection tools.

Integration of Pharmacy Practice and Pharmaceutical Analysis: Quality Assessment of Laboratory Performance.

ERIC Educational Resources Information Center

McGill, Julian E.; Holly, Deborah R.

1996-01-01

Laboratory portions of courses in pharmacy practice and pharmaceutical analysis at the Medical University of South Carolina are integrated and coordinated to provide feedback on student performance in compounding medications. Students analyze the products they prepare, with early exposure to compendia requirements and other references. Student…

Biomek 3000: the workhorse in an automated accredited forensic genetic laboratory.

PubMed

Stangegaard, Michael; Meijer, Per-Johan; Børsting, Claus; Hansen, Anders J; Morling, Niels

2012-10-01

We have implemented and validated automated protocols for a wide range of processes such as sample preparation, PCR setup, and capillary electrophoresis setup using small, simple, and inexpensive automated liquid handlers. The flexibility and ease of programming enable the Biomek 3000 to be used in many parts of the laboratory process in a modern forensic genetics laboratory with low to medium sample throughput. In conclusion, we demonstrated that sample processing for accredited forensic genetic DNA typing can be implemented on small automated liquid handlers, leading to the reduction of manual work as well as increased quality and throughput.

Sandia National Laboratories/New Mexico Environmental Baseline update--Revision 1.0

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

NONE

1996-07-01

This report provides a baseline update to provide the background information necessary for personnel to prepare clear and consise NEPA documentation. The environment of the Sandia National Laboratories is described in this document, including the ecology, meteorology, climatology, seismology, emissions, cultural resources and land use, visual resources, noise pollution, transportation, and socioeconomics.

Effect of Annealing on the Thermoluminescence Properties of ZnO Nanophosphor

NASA Astrophysics Data System (ADS)

Kalita, J. M.; Wary, G.

2017-07-01

We report the effect of annealing on the thermoluminescence (TL) properties of zinc oxide (ZnO) nanophosphor. The sample was synthesised by a wet chemical process. The characterisation report shows that the size of the grains is within 123.0 nm-160.5 nm. TL measured at 2 K/s from a fresh un-annealed sample irradiated to 60 mGy shows a composite glow curve containing three peaks at 353.2 K, 429.1 K, and 455.3 K. On the other hand, samples annealed at 473 K and 573 K followed by irradiation to 60 mGy do not give TL. However, annealing at 673 K and 773 K followed by irradiation to the same dose produces a glow curve comprising two overlapping peaks at 352.3 K and 370.6 K. In the TL emission spectrum of un-annealed sample, two emission peaks were found in green ( 523 nm) and orange ( 620 nm) regions whereas in annealed samples, only a peak was found in the orange region ( 618 nm). Kinetic analysis shows that the activation energy corresponding to TL peaks at 353.2 K, 429.1 K, and 455.3 K of the un-annealed sample are 0.64 eV, 0.80 eV, and 1.20 eV whereas that of the peaks at 352.3 K and 370.6 K of 673 K and 773 K annealed samples are 0.64 eV and 0.70 eV, respectively. All peaks of un-annealed and annealed samples, except the one at 429.1 K of the un-annealed sample, follow first-order kinetics whereas the peak at 429.1 K follows second-order kinetics. Considering the kinetic and spectral features, an energy band model for ZnO nanophosphor has been proposed.

Thermoluminescence due to tunneling in nanodosimetric materials: A Monte Carlo study

NASA Astrophysics Data System (ADS)

Pagonis, Vasilis; Truong, Phuc

2018-02-01

Thermoluminescence (TL) signals from nanodosimetric materials have been studied extensively during the past twenty years, especially in the area of nanomaterials doped with rare earths. One of the primary effects being studied experimentally have been possible correlations between the nanocrystal size and the shape and magnitude of TL signals. While there is an abundance of experimental studies attempting to establish such correlations, the underlying mechanism is not well understood. This paper is a Monte Carlo simulation study of the effect of nanocrystal size on the TL signals, for materials in which quantum tunneling is the dominant recombination mechanism. TL signals are simulated for a random distribution of electrons and positive ions, by varying the following parameters in the model: the radius of the crystal R, tunneling length a, and the relative concentrations of electrons and ions. The simulations demonstrate that as the radius of the nanocrystals becomes larger, the peaks of the TL glow curves shift towards lower temperatures and changes occur in both peak intensity and peak width. For large crystals with a constant density of positive ions, the TL glow curves reach the analytical limit expected for bulk materials. The commonly used assumption of nearest neighbor interactions is examined within the model, and simulated examples are given in which this assumption breaks down. It is demonstrated that the Monte Carlo method presented in this paper can also be used for linearly modulated infrared stimulated luminescence (LM-IRSL) signals, which are of importance in luminescence dosimetry and luminescence dating applications. New experimental data are presented for Durango apatite, a material which is known to exhibit strong anomalous fading due to tunneling; the experimental data is compared with the model. The relevance of the simulated results for luminescence dosimetry is discussed.

Impact of external haematology proficiency testing programme on quality of laboratories.

PubMed

Saxena, Renu; Katoch, S C; Srinivas, Upendra; Rao, Seema; Anand, Hema

2007-11-01

A reliable and reproducible report from a laboratory needs internal quality control within the laboratory and participation in external proficiency testing programmes (EPTP). This study conducted at the Department of Haematology, All India Institute of Medical Sciences (AIIMS), New Delhi, which has been conducting an EPTP since 1992, was undertaken to assess the efficacy of this programme in improving the performance of participating laboratories in reporting test samples sent for Hb, total leucocyte count (TLC), reticulocyte count and assessment of peripheral blood smear (PBS). The samples were prepared in our laboratory according to the International Standards Organization (ISO) guidelines. The performance of individual laboratories was assessed using robust Z score, which is an indicator of acceptability of the test result. An improvement in the overall percentage of laboratories with acceptable reports was seen during the study period. It has increased from 38,40,40 per cent in 1992 to 85, 90,94.7 per cent in 2006 for Hb, TLC, reticulocyte count, respectively. However, the results for peripheral smear assessment improved only marginally. The external haematology proficiency testing programme run by our department for Hb, TLC, reticulocyte count, and peripheral blood smear assessment, has helped in improving the reporting standards of these parameters in Indian laboratories.

Thermoluminescence characteristics of flat optical fiber in radiation dosimetry under different electron irradiation conditions

NASA Astrophysics Data System (ADS)

Alawiah, A.; Intan, A. M.; Bauk, S.; Abdul-Rashid, H. A.; Yusoff, Z.; Mokhtar, M. R.; Wan Abdullah, W. S.; Mat Sharif, K. A.; Mahdiraji, G. A.; Mahamd Adikan, F. R.; Tamchek, N.; Noor, N. M.; Bradley, D. A.

2013-05-01

Thermoluminescence (TL) flat optical fibers (FF) have been proposed as radiation sensor in medical dosimetry for both diagnostic and radiotherapy applications. A flat optical fiber with nominal dimensions of (3.226 × 3.417 × 0.980) mm3 contains pure silica SiO2 was selected for this research. The FF was annealed at 400°C for 1 h before irradiated. Kinetic parameters and dosimetric glow curve of TL response were studied in FF with respect to electron irradiation of 6 MeV, 15 MeV and 21 MeV using linear accelerator (LINAC) in the dose range of 2.0-10.0 Gy. The TL response was read using a TLD reader Harshaw Model 3500. The Time-Temperature-Profile (TTP) of the reader used includes; initial preheat temperature of 80°C, maximum readout temperature is 400°C and the heating rate of 30°Cs-1. The proposed FF shows excellent linear radiation response behavior within the clinical relevant dose range for all of these energies, good reproducibility, independence of radiation energy, independence of dose rate and exhibits a very low thermal fading. From these results, the proposed FF can be used as radiation dosimeter and favorably compares with the widely used of LiF:MgTi dosimeter in medical radiotherapy application.

Long-term Results of an Analytical Assessment of Student Compounded Preparations.

PubMed

Roark, Angie M; Anksorus, Heidi N; Shrewsbury, Robert P

2014-11-15

To investigate the long-term (ie, 6-year) impact of a required remake vs an optional remake on student performance in a compounding laboratory course in which students' compounded preparations were analyzed. The analysis data for several preparations made by students were compared for differences in the analyzed content of the active pharmaceutical ingredient (API) and the number of students who successfully compounded the preparation on the first attempt. There was a consistent statistical difference in the API amount or concentration in 4 of the preparations (diphenhydramine, ketoprofen, metoprolol, and progesterone) in each optional remake year compared to the required remake year. As the analysis requirement was continued, the outcome for each preparation approached and/or attained the expected API result. Two preparations required more than 1 year to demonstrate a statistical difference. The analytical assessment resulted in a consistent, long-term improvement in student performance during the 5-year period after the optional remake policy was instituted. Our assumption is that investment in such an assessment would result in a similar benefits at other colleges and schools of pharmacy.

Photon mass attenuation coefficients, effective atomic numbers and electron densities of some thermoluminescent dosimetric compounds

NASA Astrophysics Data System (ADS)

Gowda, Shivalinge; Krishnaveni, S.; Yashoda, T.; Umesh, T. K.; Gowda, Ramakrishna

2004-09-01

Photon mass attenuation coefficients of some thermoluminescent dosimetric (TLD) compounds, such as LiF, CaCO_3, CaSO_4, CaSO_4\\cdot2H_2O, SrSO_4, CdSO_4, BaSO_4, C_4H_6BaO_4 and 3CdSO_4\\cdot8H_2O were determined at 279.2, 320.07, 514.0, 661.6, 1115.5, 1173.2 and 1332.5 keV in a well-collimated narrow beam good geometry set-up using a high resolution, hyper pure germanium detector. The attenuation coefficient data were then used to compute the effective atomic number and the electron density of TLD compounds. The interpolation of total attenuation cross-sections of photons of energy E in elements of atomic number Z was performed using the logarithmic regression analysis of the data measured by the authors and reported earlier. The best-fit coefficients so obtained in the photon energy range of 279.2 to 320.07 keV, 514.0 to 661.6 keV and 1115.5 to 1332.5 keV by a piece-wise interpolation method were then used to find the effective atomic number and electron density of the compounds. These values are found to be in agreement with other available published values.

Structural and impurity phase transitions of LiNaSO4:RE probed using cathodo-thermoluminescence

NASA Astrophysics Data System (ADS)

Maghrabi, M.; Finch, A. A.; Townsend, P. D.

2008-11-01

Spectrally resolved cathodo-thermoluminescence spectra of rare earth (RE) doped LiNaSO4 measured from 20 to 673 K reveal several anomalies in the RE emission lines and intensities. The low (20-300 K) temperature data show a discontinuous change in intensity at ~170 K that is either a marked intensity enhancement or a drop truncating the entire spectrum. Such an effect on the host luminescence has previously been assigned to a transition between cubic and hexagonal polymorphs of ice nanoparticle inclusions. Similar, but less profound anomalies are seen above room temperature (300-673 K) where the changes take the form of either a discontinuity in intensity at ~480 K or reduced intensity in the range 430-530 K. There are changes in the relative intensities of different emission lines of the same dopant in this temperature range. Such high temperature variations are ascribed to structural phase changes within the LiNaSO4 crystals. The behaviours may result from Li-poor surfaces or twin boundaries behaving like Na2SO4. This phase change is suggested in the open literature for LiNaSO4 but not yet fully documented, perhaps because the effects span a wide range of temperatures or due to experimental features inherent in most luminescence facilities.

Thermoluminescence Dynamics During Destructions of Porous Structures Formed by Nitrogen Nanoclusters in Bulk Superfluid Helium

NASA Astrophysics Data System (ADS)

Meraki, Adil; Mao, Shun; McColgan, Patrick T.; Boltnev, Roman E.; Lee, David M.; Khmelenko, Vladimir V.

2016-11-01

We studied the dynamics of thermoluminescence during destruction of porous structures formed by nanoclusters of nitrogen molecules containing high concentrations of stabilized nitrogen atoms. The porous structures were formed in bulk superfluid helium by injection of the products of discharges in nitrogen-helium gas mixtures through the liquid helium surface. Fast recombination of nitrogen atoms during warming-up led to explosive destruction of the porous structures accompanied by bright flashes. Intense emissions from the α -group of nitrogen atoms, the β -group of oxygen atoms and the Vegard-Kaplan bands of N_2 molecules were observed at the beginning of destruction. At the end of destruction the M- and β -bands of NO molecules as well as bands of O_2 molecules were also observed. Observation of the emissions from NO molecules at the end of destruction was explained by processes of accumulation of NO molecules in the system due to the large van der Waals interaction of NO molecules. For the first time, we observed the emission of the O_2 molecules at the end of destruction of the porous nitrogen structures as a result of the (NO)_2 dimer formation in solid nitrogen and subsequent processes leading to the appearance of excited O_2 molecules.

Protocol for Cohesionless Sample Preparation for Physical Experimentation

DTIC Science & Technology

2016-05-01

protocol for specimen preparation that will enable the use of soil strength curves based on expedient field classification testing (e.g., grain-size...void ratio and relative compaction, which compares field compaction to a laboratory maximum density. Gradation charts for the two materials used in...the failure stress. Ring shear testing was performed using the GCTS Residual-Ring Shear System SRS-150 in order to measure the peak torsional

Preparation, Imaging, and Quantification of Bacterial Surface Motility Assays

PubMed Central

Morales-Soto, Nydia; Anyan, Morgen E.; Mattingly, Anne E.; Madukoma, Chinedu S.; Harvey, Cameron W.; Alber, Mark; Déziel, Eric; Kearns, Daniel B.; Shrout, Joshua D.

2015-01-01

Bacterial surface motility, such as swarming, is commonly examined in the laboratory using plate assays that necessitate specific concentrations of agar and sometimes inclusion of specific nutrients in the growth medium. The preparation of such explicit media and surface growth conditions serves to provide the favorable conditions that allow not just bacterial growth but coordinated motility of bacteria over these surfaces within thin liquid films. Reproducibility of swarm plate and other surface motility plate assays can be a major challenge. Especially for more “temperate swarmers” that exhibit motility only within agar ranges of 0.4%-0.8% (wt/vol), minor changes in protocol or laboratory environment can greatly influence swarm assay results. “Wettability”, or water content at the liquid-solid-air interface of these plate assays, is often a key variable to be controlled. An additional challenge in assessing swarming is how to quantify observed differences between any two (or more) experiments. Here we detail a versatile two-phase protocol to prepare and image swarm assays. We include guidelines to circumvent the challenges commonly associated with swarm assay media preparation and quantification of data from these assays. We specifically demonstrate our method using bacteria that express fluorescent or bioluminescent genetic reporters like green fluorescent protein (GFP), luciferase (lux operon), or cellular stains to enable time-lapse optical imaging. We further demonstrate the ability of our method to track competing swarming species in the same experiment. PMID:25938934