Science.gov

Sample records for am-be pgnaa set-up

  1. Characterization of an Am-Be PGNAA set-up developed for in situ liquid analysis: Application to domestic waste water and industrial liquid effluents analysis

    NASA Astrophysics Data System (ADS)

    Idiri, Z.; Mazrou, H.; Amokrane, A.; Bedek, S.

    2010-01-01

    A prompt gamma neutron activation analysis (PGNAA) set-up with an Am-Be source developed for in situ analysis of liquid samples is described. The linearity of its response was tested for chlorine and cadmium dissolved in water. Prompt gamma efficiency of the system has been determined experimentally using prompt gamma of chlorine dissolved in water and detection limits for different elements have been derived for domestic waste water. A methodology to analyze any kind of liquid is then proposed. This methodology consists mainly on using standards with water as bulk or in the case of absolute method, to use gamma efficiency determined with prompt gammas emitted by chlorine dissolved in water. To take into account the thermal neutron flux variations inside the samples, flux monitoring was carried out using a He-3 neutron detector placed at the external sample container surface. Finally, to correct for the differences in gamma attenuation, average gamma attenuations factors were calculated using MCNP5 code. This method was then checked successfully by determining cadmium in industrial phosphoric acid and our result was in good agreement with that obtained with inductively coupled plasma (ICP) method.

  2. Detection limits of pollutants in water for PGNAA using Am Be source

    NASA Astrophysics Data System (ADS)

    Khelifi, R.; Amokrane, A.; Bode, P.

    2007-09-01

    A basic PGNAA facility with an Am-Be neutron source is described to analyze the pollutants in water. The properties of neutron flux were determined by MCNP calculations. In order to determine the efficiency curve of a HPGe detector, the prompt-gamma rays from chlorine were used and an exponential curve was fitted. The detection limits for typical water sample are also estimated using the statistical fluctuations of the background level in the areas of recorded the prompt-gamma spectrum.

  3. A quantitative PGNAA study for use in aqueous solution measurements using Am-Be neutron source and BGO scintillation detector

    NASA Astrophysics Data System (ADS)

    Ghal-Eh, N.; Ahmadi, P.; Doost-Mohammadi, V.

    2016-02-01

    A prompt gamma neutron activation analysis (PGNAA) system including an Am-Be neutron source and BGO scintillation detector are used for quantitative analysis of bulk samples. Both Monte Carlo-simulated and experimental data are considered as input data libraries for two different procedures based on neural network and least squares methods. The results confirm the feasibility and precision of the proposed methods.

  4. A new Am-Be PGNAA setup for element determination in aqueous solution.

    PubMed

    Yongsheng, Ling; Wenbao, Jia; Daqian, Hei; Qing, Shan; Can, Cheng; Haojia, Zhang; Wenyu, Hou; Yanquan, He; Da, Chen

    2014-11-12

    A new prompt-gamma neutron activation analysis (PGNAA) setup has been designed for element determination in aqueous solution with a 300 mCi (241)Am-Be neutron source and a 4in.×3in. (diameter×height) BGO detector, uncooled. A polyethylene cylindrical sample container approximately 40cm in outer radius and 80cm in height was used. To reduce the neutron dose in the detector, a block of 5cm thickness Li2CO3 was placed between the source and the detector for separation, but no gamma-blocker was used. By adjusting the position of the detector and optimizing the geometrical conditions of the setup, the element detection limit with a low activity neutron source was further improved. This methodology was checked by simulations with chlorine, mercury and cadmium determination and by experiments with chlorine determination in aqueous samples. The results show a good linear relationship between chlorine concentration and the count of its characteristic peak, and the detection limit of chlorine can reach 41.7mg/L with a collection time of 3600s for each spectrum. Additionally, a linear relationship was identified between mercury concentration and the count of its characteristic peak, but for cadmium, a non-linear relationship was observed in the simulations. PMID:25464204

  5. New source moderator geometry to improve performance of 252Cf and 241Am Be source-based PGNAA setups

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Abdelmonem, M. S.; Al-Misned, Ghada; Al-Ghamdi, Hanan

    2006-06-01

    The gamma ray yield from a 252Cf and a 241Am-Be source-based Prompt Gamma Ray Activation Analysis (PGNAA) setup has been observed to increase with enclosing their neutrons sources in a high-density polyethylene moderator. The prompt gamma rays yield from both setups depends upon the moderator length and the source position in it. For both setups, the optimum moderator length is found to be 7 cm. The optimum position of the neutron source inside moderator of the 252Cf and the 241Am-Be source-based PGNAA setups was found to be at a distance of 0.5 and 0.75 cm from the moderator-end facing the sample, respectively. Due to enclosure of the source in the moderator, about three-fold increase has been observed in the yield of prompt gamma rays from a Portland cement sample of a 252Cf and a 241Am-Be source-based PGNAA setups.

  6. Monte Carlo optimization of sample dimensions of an 241Am Be source-based PGNAA setup for water rejects analysis

    NASA Astrophysics Data System (ADS)

    Idiri, Z.; Mazrou, H.; Beddek, S.; Amokrane, A.; Azbouche, A.

    2007-07-01

    The present paper describes the optimization of sample dimensions of a 241Am-Be neutron source-based Prompt gamma neutron activation analysis (PGNAA) setup devoted for in situ environmental water rejects analysis. The optimal dimensions have been achieved following extensive Monte Carlo neutron flux calculations using MCNP5 computer code. A validation process has been performed for the proposed preliminary setup with measurements of thermal neutron flux by activation technique of indium foils, bare and with cadmium covered sheet. Sensitive calculations were subsequently performed to simulate real conditions of in situ analysis by determining thermal neutron flux perturbations in samples according to chlorine and organic matter concentrations changes. The desired optimal sample dimensions were finally achieved once established constraints regarding neutron damage to semi-conductor gamma detector, pulse pile-up, dead time and radiation hazards were fully met.

  7. Setting up a postmortem service.

    PubMed

    der Burgt, Guda van

    2016-06-25

    Pets and pony camp, and a wish for a career that involved working with her hands, led Guda van der Burgt to study veterinary medicine at Utrecht. Starting her working life with a cattle breeding company, she moved into large animal work, industry and state veterinary medicine, all of which gave her the skills to set up a postmortem examination service. PMID:27339933

  8. Guide for SDEC Set up

    SciTech Connect

    Bibby, R; Guthrie, E

    2009-01-30

    The instrument has four collection vials that must be filled with ethylene glycol before operation. Each of the four vials should be labeled 1 through 4 and the empty weights recorded. Fill each vial with 80 mL of ethylene glycol and record the weight again. In order for the instrument to operate properly, the collection vials should always have less than 160 mL of total liquid in them. After completing a sample run, remove the collection vials, use a transfer pipette to remove any liquid that might still be on the air paddler, wipe off any condensation from the exterior of the collection vial and record weight. From the instrument, record the ending volume and the time of operation. The solution mixed in the scintillation vial will be 2 ml of a 95% to 50% ethylene glycol to water mixture. To determine the efficiency of counting at all of these concentrations, a series of vials should be set up that consist of 18 ml of Ultima Gold LLT cocktail mixed with standard, regular deionized water and ethylene glycol. The efficiency curve should be counted in the 'Low Level' count mode with the Luminescence Correction ON and the Color Quench Correction ON. Once the tSIE values are determined, chart the cpm against the tSIE numbers and find the best fit for the data. The resulting equation is to be used to converting tSIE values from the collection vials to efficiency. To determine the background cpm value of the ethylene glycol, count a 2 ml sample of ethylene glycol with 18 ml of Ultima Gold for 100 minutes. To determine the total activity of the sample, take two 2 ml aliquots of sample from the first vial and place in separate scintillation vials. Record the weight of each aliquot. Determine the percentage of total sample each aliquot represents by dividing the aliquot weight by the total solution weight from the vial. Also, determine the percentage of ethylene glycol in the sample by dividing the initial solution weight by the final solution weight and multiplying by 100

  9. Setting up Blue Ribbon Commissions. Issuegram 15.

    ERIC Educational Resources Information Center

    Palaich, Robert; And Others

    Options and suggestions for setting up successful study commissions were gathered from 10 commissions that had recommended revisions of state educational policy on a variety of issues. Composed of respected citizens from across the state, each task force was created by the governor or legislature for a fixed duration. Some recommendations for…

  10. Advice on Setting up a STEM Club

    ERIC Educational Resources Information Center

    Khan, Faisal

    2013-01-01

    Setting up a STEM club can be the most daunting item that one faces on a department's development plan. Coupled with all the other demands that exist within teaching and learning, teachers can be easily forgiven for pushing this task further and further into the school year until it eventually becomes one of next year's "to-do" items.…

  11. Setting up an Email Peer Support Scheme

    ERIC Educational Resources Information Center

    Hutson, Nicky; Cowie, Helen

    2007-01-01

    This article opens with a review of current research on peer interventions and their capacity to impact on school climate and bystander behaviour, as well as to meet the aims of fostering altruism. The main focus of the article is a study of an email support group in an all-boys school in the United Kingdom. It was set up in response to an…

  12. Setting Up Private Practice in Psychiatry*

    PubMed Central

    De Sousa, Alan; De Sousa, Avinash

    2015-01-01

    Setting up a private practice in Mumbai is an onerous task. The present paper looks at the difficulties face by young psychiatrists when starting a private practice in psychiatry. It suggests certain guidelines to be followed to ensure the development of a successful practice. It also suggests methods to gain popularity among patients and society along with the ethics to be followed, knowledge base to be garnered, and the role of using multiple therapies and versatility in private practice. PMID:25838718

  13. Setting up a medical portrait studio.

    PubMed

    Neff, Laura L; Humphrey, Clinton D; Kriet, J David

    2010-05-01

    Consistency of photographic documentation is essential for facial plastic surgery, a visual surgical subspecialty. Photographs are often used to validate surgical outcomes but have many other uses including education, publication, and marketing. Utilization of a properly equipped medical portrait studio will dramatically increase the quality of photographic images. In this article, the authors discuss the steps necessary to set up and use an officebased portrait studio. PMID:20511072

  14. Trappers set up trap for lizard

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In hope of catching a large monitor lizard seen in the area, state-licensed animal trappers Dewey Kessler and James Dean (at left), with Gary Povitch (kneeling) of the U.S. Wildlife and Dan Turner (standing) set up a trap on KSC. The lizard has been spotted recently near S.R. 3, a route into the Center, by several area residents. Turner is a monitor expert. The lizard is not a native of the area, and possibly a released pet. Dean is working with the cooperation of KSC and the Merritt Island National Wildlife Refuge.

  15. Setting up the Pediatric Endoscopy Unit.

    PubMed

    Lerner, Diana G; Pall, Harpreet

    2016-01-01

    As pediatric gastrointestinal endoscopy continues to develop and evolve, pediatric gastroenterologists are more frequently called on to develop and direct a pediatric endoscopy unit. Lack of published literature and focused training in fellowship can render decision making about design, capacity, operation, equipment purchasing, and staffing challenging. To help guide management decisions, we distributed a short survey to 18 pediatric gastroenterology centers throughout the United States and Canada. This article provides practical guidance by summarizing available expert opinions on the topic of setting up a pediatric endoscopy unit. PMID:26616893

  16. Platform for setting up interactive virtual environments

    NASA Astrophysics Data System (ADS)

    Souza, Danilo; Dias, Paulo; Santos, Daniel; Sousa Santos, Beatriz

    2014-02-01

    This paper introduces pSIVE, a platform that allows the easy setting up of Virtual Environments, with interactive information (for instance, a video or a document about a machine that is present in the virtual world) to be accessed for different 3D elements. The main goal is to create for evaluation and training on a virtual factory - but generic enough to be applied in different contexts by non-expert users (academic and touristic for instance). We show some preliminary results obtained from two different scenarios: first a production line of a factory with contextualized information associated to different elements which aimed the training of employees. Second a testing environment, to compare and assess two different selection styles that were integrated in pSIVE and to allow different users to interact with an environment created with pSIVE to collect opinions about the system. The conclusions show that the overall satisfaction was high and the comments will be considered in further platform development.

  17. In situ determination of salinity by PGNAA.

    PubMed

    Borsaru, M; Smith, C; Merritt, J; Aizawa, T; Rojc, A

    2006-05-01

    Salinity is a very important environmental issue all around the world. In many cases salinity was produced from human activities like farming and mining. Different soluble salts contribute to salinity, however, NaCl is the most common salt producing salinity. This work deals with the application of the prompt gamma neutron activation analysis (PGNAA) technique for in situ determination of salinity. The technique is based on the measurement of chlorine, a component of the common salt, by PGNAA. PMID:16448819

  18. INTERIOR PERSPECTIVE, LOOKING SOUTH SOUTHWEST WITH FIELD SET UP IN ...

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

    INTERIOR PERSPECTIVE, LOOKING SOUTH SOUTHWEST WITH FIELD SET UP IN FOOTBALL CONFIGURATION. FIELD SEATING ROTATES TO ACCOMMODATE BASEBALL GAMES. - Houston Astrodome, 8400 Kirby Drive, Houston, Harris County, TX

  19. How To Set Up Your Own Small Business. Study Guide.

    ERIC Educational Resources Information Center

    American Inst. of Small Business, Minneapolis, MN.

    This study guide is intended for use with the separately available entrepreneurship education text "How To Set Up Your Own Business." The guide includes student exercises that have been designed to accompany chapters dealing with the following topics: determining whether or not to set up a small business, doing market research, forecasting sales,…

  20. Explosives Detection and Identification by PGNAA

    SciTech Connect

    E. H. Seabury; A. J. Caffrey

    2006-04-01

    The feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices has been studied computationally, using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The Monte Carlo results, in turn were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Laboratory (INL). The results of the MCNP calculations and PINS measurements have been previously reported. In this report we describe measurements performed on actual explosives and compare the results with calculations. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another by PGNAA

  1. Explosive Detection and Identification by PGNAA

    SciTech Connect

    E.H. Seabury; A.J. Caffrey

    2004-11-01

    The goal of this project was to determine the feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices (INDs). The studies were carried out using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The model results were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Engineering and Environmental Laboratory (INEEL). The results of the MCNP calculations and PINS measurements are presented in this report. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another.

  2. Improving the safety of a body composition analyser based on the PGNAA method.

    PubMed

    Miri-Hakimabad, Hashem; Izadi-Najafabadi, Reza; Vejdani-Noghreiyan, Alireza; Panjeh, Hamed

    2007-12-01

    The 252Cf radioisotope and 241Am-Be are intense neutron emitters that are readily encapsulated in compact, portable and sealed sources. Some features such as high flux of neutron emission and reliable neutron spectrum of these sources make them suitable for the prompt gamma neutron activation analysis (PGNAA) method. The PGNAA method can be used in medicine for neutron radiography and body chemical composition analysis. 252Cf and 241Am-Be sources generate not only neutrons but also are intense gamma emitters. Furthermore, the sample in medical treatments is a human body, so it may be exposed to the bombardments of these gamma-rays. Moreover, accumulations of these high-rate gamma-rays in the detector volume cause simultaneous pulses that can be piled up and distort the spectra in the region of interest (ROI). In order to remove these disadvantages in a practical way without being concerned about losing the thermal neutron flux, a gamma-ray filter made of Pb must be employed. The paper suggests a relatively safe body chemical composition analyser (BCCA) machine that uses a spherical Pb shield, enclosing the neutron source. Gamma-ray shielding effects and the optimum radius of the spherical Pb shield have been investigated, using the MCNP-4C code, and compared with the unfiltered case, the bare source. Finally, experimental results demonstrate that an optimised gamma-ray shield for the neutron source in a BCCA can reduce effectively the risk of exposure to the 252Cf and 241Am-Be sources. PMID:18268376

  3. A quality survey on different shielding configurations of gamma ray detector used with a portable PGNAA system

    NASA Astrophysics Data System (ADS)

    Bayat, E.; Afarideh, H.; Davani, F. Abbasi; Ghal-Eh, N.

    2016-03-01

    The appropriate gamma-ray detector shielding configuration is critical for a precise prompt gamma neutron activation analysis (PGNAA) measurement. The shielding material has to prevent the radiation damage to the detector crystal and it must produce less activation gamma rays, whether prompt or delayed, which may interfere the gamma ray spectrum of the sample. In this research, using common shielding materials, a number of combinations have been studies to form a 50 cm long shield for portable PGNAA system against both fast and slow neutrons as well as gamma rays emitted by 20Ci Am-Be source. The measurement results show that in contrast with conventional shadow cone in which the shielding material starts with 20 cm heavy metals such as iron and ends with 30 cm polymer materials, in portable PGNAA systems, the shielding material gives better results if it starts with about 40 cm borated polymer material and ends with an appropriate thickness (7 cm to 10 cm) of heavy metal such as tungsten.

  4. A Magnetic Set-Up to Help Teach Newton's Laws

    ERIC Educational Resources Information Center

    Panijpan, Bhinyo; Sujarittham, Thanida; Arayathanitkul, Kwan; Tanamatayarat, Jintawat; Nopparatjamjomras, Suchai

    2009-01-01

    A set-up comprising a magnetic disc, a solenoid and a mechanical balance was used to teach first-year physics students Newton's third law with the help of a free body diagram. The image of a floating magnet immobilized by the solenoid's repulsive force should help dispel a common misconception of students as regards the first law: that stationary…

  5. Setting Up a Customer Network to Review Documentation.

    ERIC Educational Resources Information Center

    Bist, Gary; And Others

    1993-01-01

    Describes setting up a customer review network, using computer networks and fax machines, to collect customer feedback on documentation during the stages of designing and writing the information. Describes the electronic feedback from one customer in particular and how it was analyzed and used to modify the information before releasing it. (SR)

  6. Hands-on Science. Getting Set Up for Science.

    ERIC Educational Resources Information Center

    Kepler, Lynne

    1998-01-01

    Presents strategies for getting organized and creating a classroom environment that promotes science learning for primary students. Teachers must first decide what topics they are going to cover and what materials they need. Next, they should determine how to organize the materials. Finally, they should identify and set up areas in the classroom…

  7. Setting up virgin stress conditions in discrete element models

    PubMed Central

    Rojek, J.; Karlis, G.F.; Malinowski, L.J.; Beer, G.

    2013-01-01

    In the present work, a methodology for setting up virgin stress conditions in discrete element models is proposed. The developed algorithm is applicable to discrete or coupled discrete/continuum modeling of underground excavation employing the discrete element method (DEM). Since the DEM works with contact forces rather than stresses there is a need for the conversion of pre-excavation stresses to contact forces for the DEM model. Different possibilities of setting up virgin stress conditions in the DEM model are reviewed and critically assessed. Finally, a new method to obtain a discrete element model with contact forces equivalent to given macroscopic virgin stresses is proposed. The test examples presented show that good results may be obtained regardless of the shape of the DEM domain. PMID:27087731

  8. Essential Requirements to Setting up an Aesthetic Practice

    PubMed Central

    Sachdev, Mukta; Britto, Gillian R

    2014-01-01

    Aesthetic dermatology is becoming a vital and popular branch of medicine. This article aims to guide dermatologists to set up a professional and ethical aesthetic practice. Dermatologists should have an integrated practice of clinical dermatology, dermatosurgery and cosmetic dermatology. Ethical practice is the gold standard for any medical field, especially with dermatologists, who should avoid doing unnecessary procedures. Proper patient counselling and addressing the patients’ concerns is imperative. PMID:25538440

  9. Setting up the water chemistry for thermal water treatment

    NASA Astrophysics Data System (ADS)

    Boglovskii, A. V.; Chernozubov, V. B.; Chernykh, N. E.; Gorbunov, A. V.; Birdin, R. Kh.

    2007-07-01

    Results are presented from the development and setting up of water-chemistry conditions for a thermal water treatment process that allows saline effluents from a boiler house to be eliminated. Peculiarities of reducing scale formation in the evaporator through the use of chalk primer and type PAF-13A antiscale agent are discussed. The results of industrial tests of a thermal water treatment plant are presented that confirm the possibility of producing makeup water for heating networks and steam boilers.

  10. Evaluation the nonlinear response function of a 3 x 3 in NaI scintillation detector for PGNAA applications.

    PubMed

    Miri Hakimabad, Hashem; Panjeh, Hamed; Vejdani-Noghreiyan, Alireza

    2007-08-01

    Response functions of the 3 x 3 in NaI detector, which is mainly used in PGNAA applications, have been calculated by using MCNP-4C code. Calculated results are compared with measured data by using standard gamma-ray sources and prompt gamma-rays from pure element samples to check their accuracy. Prompt gamma-rays from pure element samples were used for this determination in the range from 1.942 to 10.829 MeV by use of (241)Am-Be neutron source and gamma-rays from radioisotope sources were used in the range from 0.081 to 4.438 MeV. Through the precise modeling of the detector structure, the agreement between both results has been improved. A surprising result is that in the PGNAA method the agreement between the MCNP simulation and experiment will be better by using a suitable neutron shield for NaI detector in order to prevent the activation of NaI (Tl) and a proper gamma-shield to attenuate the high-rate 4.438 MeV gamma-ray, (241)Am-Be gamma-ray component. PMID:17485218

  11. Inertial Electrostatic Confinement Fusion: Set-Up and Operation

    NASA Technical Reports Server (NTRS)

    Hurst, Chantelle M.

    1999-01-01

    During the research period focus was placed upon set-up, installment, and operation of the IEC. While procurement of specific components was difficult, the IEC was on several occasions demonstrated to be practical and safe during operation. Over the course of the summer several different grids were tested and various modes were obtained. While hard data was not produced, the IEC did something more important, which was to become established here at Marshall and pave the way for future IEC systems to be built.

  12. Neutron and gamma-ray spectra of 239PuBe and 241AmBe.

    PubMed

    Vega-Carrillo, Héctor René; Manzanares-Acuña, Eduardo; Becerra-Ferreiro, Ana María; Carrillo-Nuñez, Aureliano

    2002-08-01

    Neutron and gamma-ray spectra of 239PuBe and 241AmBe were measured and their dosimetric features were calculated. Neutron spectra were measured using a multisphere neutron spectrometer with a 6LiI(Eu) scintillator. The 239PuBe neutron spectrum was measured in an open environment, while the 241AmBe neutron spectrum was measured in a closed environment. Gamma-ray spectra were measured using a NaI(Tl) scintillator using the same experimental conditions for both sources. The effect of measuring conditions for the 241AmBe neutron spectrum indicates the presence of epithermal and thermal neutrons. The low-resolution neutron spectra obtained with the multisphere spectrometer allows one to calculate the dosimetric features of neutron sources. At 100 cm both sources produce approximately the same count rate as that of the 4.4 MeV gamma-ray per unit of alpha emitter activity. PMID:12150274

  13. Quantifying the accuracy of laboratory SIP experimental set ups

    NASA Astrophysics Data System (ADS)

    Ntarlagiannis, D.; Slater, L. D.

    2014-12-01

    Over the last decade the spectral induced polarization (SIP) method has reemerged as a promising method for subsurface investigations. The sensitivity of SIP to bulk and interfacial physicochemical properties permits a wider range of hydrogeophysical and environmental applications, including monitoring of subsurface biogeochemical transformations. Improvements in instrumentation and experimental designs, along with faster acquisition capabilities and easy access to processing routines are encouraging novel applications of the method, and support quantitative interpretation of the data acquired. Motivated by recent research that focus on small scale changes, over large frequency ranges, we performed a series of experiments to identify the accuracy of common laboratory SIP experimental set ups. We performed measurements on resistor - capacitor (RC) networks, to identify the instrumentation accuracy, and also on standard laboratory columns filled with materials of known SIP response, primarily on well characterized fluids of different conductivity. Early results show small errors in the low frequency range, attributed to electrode polarization; in higher frequencies, typically above 1000 Hz, the errors may become significant limiting the meaningful interpretation of small phase angles at these frequencies. The data will be compared with published data using comparable experimental set ups, and could be used to set realistic expectations on future SIP experiments and applications. With this work we aim at developing a best practices document that can aid the SIP user in collecting meaningful and repeatable results.

  14. A portable active interrogation system using a switchable AmBe neutron source

    NASA Astrophysics Data System (ADS)

    Allen, Matthew; Hertz, Kristin; Kunz, Christopher; Mascarenhas, Nicholas

    2005-09-01

    Active neutron interrogation is an effective technique used to locate fissionable material. This paper discusses a portable system that utilizes a AmBe neutron source. The AmBe source consists of an americium alpha source and a beryllium target that can be switched into alignment to turn the source on and out of alignment to turn the source off. This offers a battery operated backpack portable source. The detector system that has been fabricated for use with this source is a fifteen tube 3He neutron detector. The results of initial experiments with the detector and MCNP calculations are discussed.

  15. Feasibility study of prompt gamma neutron activation analysis (PGNAA) of explosives simulants and bulk material using DD/DT neutron generator

    NASA Astrophysics Data System (ADS)

    Bishnoi, S.; Sarkar, P. S.; Patel, T.; Adhikari, P. S.; Sinha, Amar

    2013-04-01

    Elemental characterization of low Z elements (C,H,Cl,Fe) inside bulk materials were performed using PGNAA technique. Samples having elemental composition similar to explosives were used for such experimentations using moderated DD neutrons as well as DT(14MeV) neutrons. We could observe characteristic prompt capture gamma rays of hydrogen (2.224MeV), nitrogen (10.83 MeV), chlorine (6.11 MeV) and Fe (6.02MeV and 7.63MeV) also (n,n'γ) prompt gamma signal (4.43MeV) of carbon. BGO detector has been used for gamma spectrum acquisition. These experimentations has been carried out for initial feasibility studies of detecting prompt gamma lines as a part of PGNAA technique based explosive detection system development. A detail description of experimental set up and procedure has been discussed in paper.

  16. AEC set-up optimisation with computed radiography imaging.

    PubMed

    Mazzocchi, S; Belli, G; Busoni, S; Gori, C; Menchi, I; Salucci, P; Taddeucci, A; Zatelli, G

    2005-01-01

    Phototimer set-up is a critical procedure for dose and image quality optimisation in computed radiography (CR) systems. While a conventional radiography automatic exposure control device (AEC) can be calibrated in order to gain a constant optical density on the film independent of beam quality and patient size, CR detectors present a high dynamic range which allows a much larger dose interval, but with different image quality levels. CR leads to a less frequent exam repetition, but may produce quite noisy images if the exposure level on the plate is not correct. The aim of this work is to evaluate the performance of a CR plate (Agfa MD40) in order to optimally calibrate an AEC device. The plate response has been characterised in terms of digital signal, exposure on the plate and signal-to-noise ratio for different beam qualities, in a patient of standard size. PMID:16461503

  17. Calibration of a Background Oriented Schlieren (BOS) Set-up

    NASA Astrophysics Data System (ADS)

    Porta, David; Echeverría, Carlos; Cardoso, Hiroki; Aguayo, Alejandro; Stern, Catalina

    2014-11-01

    We use two materials with different known indexes of refraction to calibrate a Background Oriented Schlieren (BOS) experimental set-up, and to validate the Lorenz-Lorentz equation. BOS is used in our experiments to determine local changes of density in the shock pattern of an axisymmetric supersonic air jet. It is important to validate, in particular, the Gladstone Dale approximation (index of refraction close to one) in our experimental conditions and determine the uncertainty of our density measurements. In some cases, the index of refraction of the material is well known, but in others the density is measured and related to the displacement field. We acknowledge support from UNAM through DGAPA PAPIIT IN117712 and the Graduate Program in Mechanical Engineering.

  18. Optimizing the application of entomopathogenic nematodes: experimental set-up.

    PubMed

    Brusselman, E; Steurbaut, W; Sonck, B

    2007-01-01

    The complex issue concerning the spray application of Entomopathogenic Nematodes (EPNs) with a hydraulic sprayer is still not solved. This research project focuses on the effect of spray application technique on the viability and deposition of EPNs. In this paper the experimental set-up used for this evaluation is described. A modular spray application system has been developed and is currently used to evaluate the effect of different parts of a sprayer on the viability of the EPNs. Based on the results of experiments using this modular spray application system, recommendations regarding pump type, mixing system, nozzle type and filter size will be formulated. Because of the large number of experiments in this research project, an image analysis system for the determination of the viability of the nematodes is developed. This paper describes two experiments comparing the new developed image processing technique with the standard microscopic counting technique. PMID:18399427

  19. Automated lithology prediction from PGNAA and other geophysical logs.

    PubMed

    Borsaru, M; Zhou, B; Aizawa, T; Karashima, H; Hashimoto, T

    2006-02-01

    Different methods of lithology predictions from geophysical data have been developed in the last 15 years. The geophysical logs used for predicting lithology are the conventional logs: sonic, neutron-neutron, gamma (total natural-gamma) and density (backscattered gamma-gamma). The prompt gamma neutron activation analysis (PGNAA) is another established geophysical logging technique for in situ element analysis of rocks in boreholes. The work described in this paper was carried out to investigate the application of PGNAA to the lithology interpretation. The data interpretation was conducted using the automatic interpretation program LogTrans based on statistical analysis. Limited test suggests that PGNAA logging data can be used to predict the lithology. A success rate of 73% for lithology prediction was achieved from PGNAA logging data only. It can also be used in conjunction with the conventional geophysical logs to enhance the lithology prediction. PMID:16140021

  20. Benchmarking MCNP and TRIPOLI with PGNAA measurements

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

    The French Alternative Energies and Atomic Energy Commission (CEA Cadarache), the Forschungszentrum Jülich GmbH (FZJ), and the RWTH Aachen University (RWTH) are involved in a cooperation aiming at characterizing toxic and reactive elements in radioactive waste packages by means of Prompt Gamma Neutron Activation Analysis (PGNAA). The design of an optimized measurement system and the assessment of its performances for realistic scenarios can be conveniently studied by numerical Monte Carlo simulation, provided the model and nuclear data offer a sufficient precision. Previous studies performed with MCNP have shown that when the nuclear data libraries lack of precision, relevant results can still be obtained by performing calculations in multiple steps (by first determining the radiative capture rate, and transporting the induced gamma toward the detector) and by injecting valid gamma-ray production data in-between [1]. In such cases, it is interesting to compare the results obtained with different codes. In the present paper, we propose to compare the MCNP and TRIPOLI codes with measurements obtained in MEDINA (Multi Element Detection based on Instrumental Neutron Activation), which is the new FZJ PGNAA facility [2]. The aim of the measurement campaign is to assess capture gamma rays of toxic elements that can be found in 200 L waste drums which are expected for geological repository.

  1. Monte Carlo simulations for design of the KFUPM PGNAA facility

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Nagadi, M. M.; Khateeb-ur-Rehman; Maslehuddin, M.; Kidwai, S.

    2003-02-01

    Monte Carlo simulations were carried out to design a 2.8 MeV neutron-based prompt gamma ray neutron activation analysis (PGNAA) setup for elemental analysis of cement samples. The elemental analysis was carried out using prompt gamma rays produced through capture of thermal neutrons in sample nuclei. The basic design of the PGNAA setup consists of a cylindrical cement sample enclosed in a cylindrical high-density polyethylene moderator placed between a neutron source and a gamma ray detector. In these simulations the predominant geometrical parameters of the PGNAA setup were optimized, including moderator size, sample size and shielding of the detector. Using the results of the simulations, an experimental PGNAA setup was then fabricated at the 350 kV Accelerator Laboratory of this University. The design calculations were checked experimentally through thermal neutron flux measurements inside the PGNAA moderator. A test prompt gamma ray spectrum of the PGNAA setup was also acquired from a Portland cement sample, using a pulsed beam of 2.8 MeV neutrons. Prompt gamma ray peaks due to the calcium, silicon and iron content of the Portland cement were detected.

  2. Setting up a veterinary medicine skills lab in Germany.

    PubMed

    Dilly, Marc; Tipold, Andrea; Schaper, Elisabeth; Ehlers, Jan P

    2014-01-01

    The amendments introduced to the current Veterinary Licensing Ordinance (TAppV) by the Veterinary Licensing Regulation (TAppO) have brought a high degree of skills orientation to fill the gap between academic study and preparing for a wide range of professional skills. In order to improve the veterinary skills of students while conveying fundamental methods in a structured and reproducible way, the University of Veterinary Medicine Hannover, Foundation, has set up the first central veterinary skills lab in Germany. Practical training is provided by means of a three-tier delivery approach. This involves around 40 simulators on an area of approx. 800 m(2) under the guidance of 6-8 staff members, along with supplementary resources such as posters, text instructions and YouTube videos. Since it opened in March 2013, there have been 769 visits to the skills lab and 30,734 hits on YouTube. Initial results show that the skills lab helps to maintain student motivation by teaching them practical skills at an early stage of the basic study-based acquisition of knowledge, whilst reinforcing skills acquisition per se in competence-based teaching. It enables veterinary students to prepare for their first examinations and treatments of live patients in a manner compliant with animal welfare. PMID:24872855

  3. Setting up and running molecular dynamics simulations of membrane proteins.

    PubMed

    Kandt, Christian; Ash, Walter L; Tieleman, D Peter

    2007-04-01

    Molecular dynamics simulations have become a popular and powerful technique to study lipids and membrane proteins. We present some general questions and issues that should be considered prior to embarking on molecular dynamics simulation studies of membrane proteins and review common simulation methods. We suggest a practical approach to setting up and running simulations of membrane proteins, and introduce two new (related) methods to embed a protein in a lipid bilayer. Both methods rely on placing lipids and the protein(s) on a widely spaced grid and then 'shrinking' the grid until the bilayer with the protein has the desired density, with lipids neatly packed around the protein. When starting from a grid based on a single lipid structure, or several potentially different lipid structures (method 1), the bilayer will start well-packed but requires more equilibration. When starting from a pre-equilibrated bilayer, either pure or mixed, most of the structure of the bilayer stays intact, reducing equilibration time (method 2). The main advantages of these methods are that they minimize equilibration time and can be almost completely automated, nearly eliminating one time consuming step in MD simulations of membrane proteins. PMID:17367719

  4. [New methodology for heavy metals measurement in water samples by PGNAA-XRF].

    PubMed

    Jia, Wen-Bao; Zhang, Yan; Hei, Da-Qian; Ling, Yong-Sheng; Shan, Qing; Cheng, Can

    2014-11-01

    In the present paper, a new combined detection method was proposed using prompt gamma neutron activation analysis (PGNAA) and characteristic X-ray fluorescence to improve the heavy metals measurement accuracy for in-situ environmental water rejects analysis by PGNAA technology. Especially, the characteristic X-ray fluorescence (XRF) of heavy metals is induced by prompt gamma-ray directly instead of the traditional excitation sources. Thus, a combined measurement facility with an 241 AmBe neutron source, a BGO detector and a NaI-Be detector was developed to analyze the pollutants in water. The two detectors were respectively used to record prompt gamma-ray and characteristic X-ray fluorescence of heavy metals. The prompt gamma-ray intensity (I(γ)) and characteristic X-ray fluorescence intensity (I(x)) was determined by MCNP calculations for different concentration (c(i)) of chromium (Cr), cadmium (Cd), mercury (Hg) and lead (Pb), respectively. The simulation results showed that there was a good linear relationship between I(γ), I(x) and (c(i)), respectively. The empirical formula of combined detection method was given based on the above calculations. It was found that the combined detection method was more sensitive for high atomic number heavy metals like Hg and Pb measurement than low atomic number like Cr and Cd by comparing and analyzing I(γ) and I(x). The limits of detection for Hg and Pb by the combined measurement instrument were 17.4 and 24.2 mg x kg(-1), respectively. PMID:25752071

  5. Progress in Development of Dense Plasma Focus Pinch for AmBe Radiological Source Replacement

    NASA Astrophysics Data System (ADS)

    Falabella, Steve; Povilus, Alex; Schmidt, Andrea; Ellsworth, Jennifer; Link, Anthony; Sears, Jason; Higginson, Drew; Jiang, Sheng

    2015-11-01

    A dense plasma focus (DPF) is a compact plasma gun accelerator that can produce intense, high energy ion beams (multiple MeV). These ion beams could be used to replace radiological sources for a variety of applications. Using a 2kJ DPF with a helium gas fill, alpha particles are accelerated into a beryllium target in order to generate a neutron spectrum similar to an AmBe source. We report on initial observations of neutron yields for this system and efforts to optimize and improve repeatability of pinch performance. In particular, incorporating results from newly-developed kinetic LSP simulations, we demonstrated higher neutron yields by adjusting the geometry of the anode electrode. In addition, we present preliminary measurements for energy distributions of ions accelerated by the pinch. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work supported by US DOE/NA-22 Office of Non-proliferation Research and Development.

  6. Validity test of design calculations of a PGNAA setup

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Garwan, M. A.

    2004-01-01

    A rectangular moderator has been designed for the prompt gamma ray neutron activation analysis (PGNAA) setup at King Fahd University of Petroleum and Minerals (KFUPM) to analyze Portland cement samples. The design of the moderator assembly was obtained using Monte Carlo calculations. The design calculations of the new rectangular moderator of the KFUPM PGNAA setup have been verified experimentally through prompt gamma ray yield measurement as a function of the front moderator thickness. In this study the yield of the 3.54 and 4.94 MeV prompt gamma rays from silicon in a soil sample was measured as a function of thickness of the front moderator of the rectangular moderator. The experimental results were compared with the results of the Monte Carlo simulations. A good agreement has been achieved between the experimental results and the results of the calculations. The experimental results have provided useful information about the PGNAA setup performance, neutron moderation, and gamma ray attenuation in the PGNAA sample.

  7. Uncertainty in patient set-up margin analysis in radiation therapy

    PubMed Central

    Suzuki, Junji; Tateoka, Kunihiko; Shima, Katsumi; Yaegashi, Yuji; Fujimoto, Kazunori; Saitoh, Yuichi; Nakata, Akihiro; Abe, Tadanori; Nakazawa, Takuya; Sakata, Kouichi; Hareyama, Masato

    2012-01-01

    We investigated the uncertainty in patient set-up margin analysis with a small dataset consisting of a limited number of clinical cases over a short time period, and propose a method for determining the optimum set-up margin. Patient set-up errors from 555 registration images of 15 patients with prostate cancer were tested for normality using a quantile-quantile (Q-Q) plot and a Kolmogorov–Smirnov test with the hypothesis that the data were not normally distributed. The ranges of set-up errors include the set-up errors within the 95% interval of the entire patient data histogram, and their equivalent normal distributions were compared. The patient set-up error was not normally distributed. When the patient set-up error distribution was assumed to have a normal distribution, an underestimate of the actual set-up error occurred in some patients but an overestimate occurred in others. When using a limited dataset for patient set-up errors, which consists of only a small number of the cases over a short period of time in a clinical practice, the 2.5% and 97.5% intervals of the actual patient data histogram from the percentile method should be used for estimating the set-up margin. Since set-up error data is usually not normally distributed, these intervals should provide a more accurate estimate of set-up margin. In this way, the uncertainty in patient set-up margin analysis in radiation therapy can be reduced. PMID:22843628

  8. Recovery of {sup 241}Am/Be neutron sources, Wooster, Ohio

    SciTech Connect

    Tompkins, J.A.; Wannigman, D.; Hatler, V.

    1998-07-01

    In August 1997, the Nuclear Regulatory Commission (NRC) submitted to the US Department of Energy (DOE) a partial list of licensed radioactive sealed sources to be recovered under a pilot project initiating Radioactive Source Recovery Program (RSRP) operations. The first of the pilot project recoveries was scheduled for September 1997 at Eastern Well Surveys in Wooster, Ohio, a company with five unwanted sealed sources on the NRC list. The sources were neutron emitters, each containing {sup 241}Am/Be with activities ranging from 2.49 to 3.0 Ci. A prior radiological survey had established that one of these sources, a Gulf Nuclear Model 71-1 containing 3 Ci of {sup 241}Am, was contaminated with {sup 241}Am and might be leaking. The other four sources were obsolete and could no longer be used by Eastern Well Surveys for their intended application in well-logging applications due to NRC decertification of these sources. All of the sources exceeded the limits established for Class C waste under 10 CFR 61.55 and, as a result, are the ultimate responsibility of the DOE under the provisions of PL 99-240. This report describes the cooperative effort between the DOE and NRC to recover the sources and transport them to Los Alamos National Laboratory (LANL) for deactivation under the RSRP. This operation alleviated any potential risk to the public health and safety from the site which might result from the leaking neutron sources or the potential mismanagement of unwanted sources. The on-site recovery occurred on September 23, 1997, and was performed by personnel from LANL and its contractor and was observed by staff from the Region III office of the NRC. All aspects of the recovery were successfully accomplished, and the sources were received at LANL on September 29, 1997. Experience gained during this operation will be used to formulate operational poilicies and procedures which will contribute to the eventual routine recovery operations of a full-scale RSRP.

  9. Setting up and Running a School Library. Information Collection and Exchange Publication No. ED204

    ERIC Educational Resources Information Center

    Baird, Nicola

    2012-01-01

    This book explains how teachers can set up and run a successful school library. In it you will find advice and information on how to: (1) set up a small library and build bookshelves; (2) select books for your library; (3) make a written record of your school's books, pamphlets and other library stock such as newspapers, magazines, audio tapes and…

  10. Prototype electron lens set-up for the Tevatron beam-beam compensation

    SciTech Connect

    Crawford, C.; Saewert, G.; Santucci, J.; Sery, A.; Shemyakin, A.; Shiltsev, V.; Wildman, D.; Aleksandrov, A.; Arapov, L.; Kuznetsov, G.; Logachov, P.; Sharapa, A.; Skarbo, B.; Sukhina, B.

    1999-05-17

    A prototype "electron lens" for the Tevatron beam-beam compensation project is commissioned at Fermilab. We de-scribe the set-up, report results of the first tests of the elec-tron beam, and discuss future plans.

  11. Measurement of lime/silica ratio in concrete using PGNAA technique

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Nagadi, M. M.; Al-Amoudi, O. S. B.

    2005-12-01

    Prompt gamma neutron activation analysis (PGNAA) technique has been used to determine lime/silica ratio in concrete samples using an accelerator-based PGNAA facility. The ratio was determined from the measured yield of 6.42 MeV prompt γ-rays of calcium and 4.93 MeV γ-rays of silicon from the six concrete samples. The experimental results were compared with the results of the Monte Carlo simulations. An excellent agreement has been achieved between the two. The study has demonstrated successful use of the accelerator-based PGNAA setup in non-destructive analysis of the concrete samples.

  12. NONDESTRUCTIVE IDENTIFICATION OF CHEMICAL WARFARE AGENTS AND EXPLOSIVES BY NEUTRON GENERATOR-DRIVEN PGNAA

    SciTech Connect

    T. R. Twomey; A. J. Caffrey; D. L. Chichester

    2007-02-01

    Prompt gamma-ray neutron activation analysis (PGNAA) is now a proven method for the identification of chemical warfare agents and explosives in military projectiles and storage containers. Idaho National Laboratory is developing a next-generation PGNAA instrument based on the new Ortec Detective mechanically-cooled HPGe detector and a neutron generator. In this paper we review PGNAA analysis of suspect chemical warfare munitions, and we discuss the advantages and disadvantages of replacing the californium-252 radioisotopic neutron source with a compact accelerator neutron generator.

  13. Experimental Set-Up to Evaluate the Degradation of the Optical Components of a CPV Module

    NASA Astrophysics Data System (ADS)

    Bengoechea, Jaione; Ezquer, Mikel; Petrina, Iñigo; Lagunas, Ana Rosa

    2011-12-01

    The efficiency of CPV modules strongly depends on the characteristics and performance of the optical components. Therefore, the complete characterization of the optical components and their evolution during the module lifetime becomes an important issue to correctly estimate the energy supplied by the CPV systems along the time. Due to the series electrical connection of the multi-junction solar cells, the spectral distribution of the light after the optical components plays a key role in the energy production. A spectrally resolved characterization of the light is hence desirable. In this paper, an indoor set-up to study the degradation of optical components of CPV modules is presented. The first part of the experimental set-up consists of a collimated Xe lamp, a diaphragm, and a spectroradiometer. With this set-up information about the variation of the light spectrum spatial distribution due to the CPV optical component is obtained. The second part of the experimental set-up is based on a combination of Deuterium and Halogen lamps and an integrating sphere. This set-up allows the detection of changes in the optical properties of the material through the measurement of the global spectral transmittance and reflectance.

  14. A dynamometer set up for simulation of a wave energy operated Wells turbine

    SciTech Connect

    Narayanan, S.S.Y.; Bose, S.

    1995-12-31

    The present trend in the world is to go for ecologically friendly methods of power generation. In this paper a dynamometer set up simulating a wave energy driven Wells turbine with proper scaling is proposed. This is a new dynamic drive test set up for evaluation of alternative generator configurations. Open loop and closed loop (P, PI and PLL controllers with speed and current feedbacks) studies are carried out on the set up. The references used as input in the closed loop simulations, vary dynamically as the data recorded at the site. The behavior of a typical wave energy operated Wells turbine is studied and simulations are also carried out with axial velocity given as input. Both steady state and d-q theory approaches are used for the modeling of the load induction generator feeding power to the grid.

  15. A pdpa laser-based measuring set-up for the characterisation of spray nozzles.

    PubMed

    Nuyttens, D; Sonck, B; de Schampheleire, M; Steurbaut, W; Baetens, K; Verboven, P; Nicolaï, B; Ramon, H

    2005-01-01

    The characteristics of agricultural sprays belong to the most critical factors affecting spray drift, deposition on plants, spray coverage and biological efficacy. Hence, within the framework of a research project about agricultural spray drift, a measuring set-up for the characterisation of spray nozzles using a Phase Doppler Particle Analyser (PDPA) was developed. This set-up is able to measure droplet sizes and velocities based on light-scattering principles. It is composed of different parts i.e.: a climate room, a spray unit, a three-dimensional automated positioning system and an Aerometrics PDPA 1D system. This paper presents a detailed description of this measuring set-up along with some first measuring results. These measurements will be used as an input for a Computational Fluid Dynamics drift-prediction model and to classify nozzles based on their driftability. PMID:16628951

  16. How to set up a GIS program at a Minority University/College

    NASA Astrophysics Data System (ADS)

    Mannel, S.

    2008-12-01

    This presentation provides detailed ideas on how to set up a GIS program and how to develop it for maximum benefits in the areas of education, research, and community outreach. We draw our experience from setting up the GIS program at Oglala Lakota College (OLC), Pine Ridge Reservation in South Dakota and work at the University of the Virgin Islands. GIS can be useful in many fields and is inexpensive to set up. Native Americans applied science in the past and now embrace GIS technology for everyday decision making. This presentation shows the wide range of GIS applications using OLC's GIS program as an example. We present our educational activities, research and community outreach. This presentation will give detailed advice of what works (and what doesn't) and to promote geospatial technology to other tribal or non-tribal colleges and universities.

  17. Development of portable experimental set-up for AFM to work at cryogenic temperature

    NASA Astrophysics Data System (ADS)

    Agarwal, D. H.; Bhatt, P. M.; Pathan, A. M.; Patel, Hitarthi; Joshi, U. S.

    2012-06-01

    We report on the designing aspects and fabrication of low temperature atomic force microscope (AFM) to study the surface structures of nanomaterials. Several key features of design including liquid nitrogen reservoir, vacuum chamber, vibration isolation table etc. have been presented. The whole set up was assembled in-house at a fairly low cost to be used with any commercial AFM system. The surface morphology of important oxide (In0.94Sn0.04)2O3 (ITO) thin film nanostructures has been investigated using the cryogenic AFM set up.

  18. Experimental designs and their recent advances in set-up, data interpretation, and analytical applications.

    PubMed

    Dejaegher, Bieke; Heyden, Yvan Vander

    2011-09-10

    In this review, the set-up and data interpretation of experimental designs (screening, response surface, and mixture designs) are discussed. Advanced set-ups considered are the application of D-optimal and supersaturated designs as screening designs. Advanced data interpretation approaches discussed are an adaptation of the algorithm of Dong and the estimation of factor effects from supersaturated design results. Finally, some analytical applications in separation science, on the one hand, and formulation-, product-, or process optimization, on the other, are discussed. PMID:21632194

  19. Prompt Gamma-Ray Neutron Activation Analysis (PGNAA) for Elemental Analysis

    SciTech Connect

    Robin P. Gardner

    2006-04-11

    This research project was to improve the prompt gamma-ray neutron activation analysis (PGNAA) measurement approach for bulk analysis, oil well logging, and small sample thermal enutron bean applications.

  20. Students' Errors in Setting up Difference Quotients and Connections to Their Conceptions of Function

    ERIC Educational Resources Information Center

    Tang, Gail

    2012-01-01

    Although finding the limits of the difference quotients in the definitions of the derivative is troubling for many students, a difficulty that preceded this confusion was observed: students were not able to correctly set up the difference quotients as required in the definitions. The purpose of this study is to uncover student errors in setting up…

  1. Setting Up On-Line Support Groups Using the Palace Software.

    ERIC Educational Resources Information Center

    Page, Betsy J.; Delmonico, David L.; Walsh, Jacqueline; L'Amoreaux, Nadene A.; Danninhirsh, Carrie; Thompson, Rebecca S.; Ingram, Albert I.; Evans, Alan D.

    2000-01-01

    Describes the process of setting up on-line support groups using The Palace, an Internet software that establishes a graphical room for the group. Describes the process of installing the software and illustrates operating it during the group. Discusses considerations for group planning including selection of leader, selection and orientation of…

  2. Setting up and Running a Loss and Bereavement Support Group for Adults with Learning Disabilities

    ERIC Educational Resources Information Center

    Boyden, Paul; Freeman, Adele; Offen, Liz

    2010-01-01

    Following evidence based literature, the Birmingham Clinical Psychology Service for People with Learning Disabilities ran a Loss and Bereavement Psychotherapy Group. The group consisted of five adults with mild learning disabilities, who met for 8 consecutive weeks. This paper reports the process of setting up a bereavement group for people with…

  3. A Guide To Setting Up a Creative Art Experiences Program for Older Adults with Developmental Disabilities.

    ERIC Educational Resources Information Center

    Harlan, Jane E.

    This guide is intended to help agencies serving older adults with mental retardation and other developmental disabilities in setting up a relatively inexpensive creative art program. The first section presents a rationale for creative art experiences for this population and then provides specific information on program development, including…

  4. Nurse-led clinics: 10 essential steps to setting up a service.

    PubMed

    Hatchett, Richard

    This article outlines 10 key steps for practitioners to consider when setting up and running a nurse-led clinic. It lays emphasis on careful planning, professional development and the need to audit and evaluate the service to ensure the clinic is measurably effective. PMID:19068891

  5. How To Set Up Your Own Small Business. Volumes I-II and Overhead Transparencies.

    ERIC Educational Resources Information Center

    Fallek, Max

    This two-volume textbook and collection of overhead transparency masters is intended for use in a course in setting up a small business. The following topics are covered in the first volume: getting off to a good start, doing market research, forecasting sales, financing a small business, understanding the different legal needs of different types…

  6. The Use of Instructional and Motivational Self-Talk in Setting up a Physical Education Lesson

    ERIC Educational Resources Information Center

    Zourbanos, Nikos

    2013-01-01

    The main purpose of this article is to provide guidelines to physical educators for setting up a self-talk program during their lesson. The article briefly presents definitions of self-talk and research findings in sport and physical education to highlight the important benefits of positive self-talk in enhancing task performance. It also provides…

  7. A Guide for Setting Up a Church-Sponsored Nursery School.

    ERIC Educational Resources Information Center

    Hostrawser, Sara

    This document provides a guide for setting up a church-sponsored nursery school. Chapter One outlines the verbal-cognitive model of preschool education which emphasizes interaction between teacher and child. Perceptual, motor, cognitive, social, emotional, and language objectives are indicated. Chapter Two covers aspects of school management such…

  8. Astronaut Andrew M. Allen, mission commander, sets up systems for a television downlink on the

    NASA Technical Reports Server (NTRS)

    1996-01-01

    STS-75 ONBOARD VIEW --- Astronaut Andrew M. Allen, mission commander, sets up systems for a television downlink on the flight deck of the Space Shuttle Columbia. Allen was joined by four other astronauts and an international payload specialist for more than 16 days of research aboard Columbia. The photograph was taken with a 70mm handheld camera.

  9. How To Set Up Your Own Small Business. Study Guide Keyed.

    ERIC Educational Resources Information Center

    American Inst. of Small Business, Minneapolis, MN.

    This study guide, which includes the answers to student exercises included in it, is intended for use with the separately available entrepreneurship education text "How To Set Up Your Own Business." The guide includes student exercises and answers that have been designed to accompany chapters dealing with the following topics: deciding whether or…

  10. Worms Eat My Garbage. How To Set Up and Maintain a Worm Composting System. First Edition.

    ERIC Educational Resources Information Center

    Appelhof, Mary

    This book is a resource for parents and teachers who want to teach about recycling and composting by setting up and maintaining a worm composting system. It is designed to be a detailed yet simple manual of vermicomposting. The manual covers the basics of vermicomposting and answers such questions as where to store a composting container, what…

  11. Set up and Operation of Video Cassette Recorders or "...How Do I Work This Thing???"

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau.

    Designed to assist Alaskans in making optimum use of the LearnAlaska TV transmitter network, this booklet provides instructions for the operation and maintenance of videocassette recorders (VCRs). After a brief introduction, which lists state film library addresses for ordering an accompanying videocassette entitled "Set Up & Operation for VCRs…

  12. The application of PGNAA borehole logging for copper grade estimation at Chuquicamata mine.

    PubMed

    Charbucinski, J; Duran, O; Freraut, R; Heresi, N; Pineyro, I

    2004-05-01

    The field trials of a prompt gamma neutron activation (PGNAA) spectrometric logging method and instrumentation (SIROLOG) for copper grade estimation in production holes of a porphyry type copper ore mine, Chuquicamata in Chile, are described. Examples of data analysis, calibration procedures and copper grade profiles are provided. The field tests have proved the suitability of the PGNAA logging system for in situ quality control of copper ore. PMID:15082058

  13. Characterization of a Sealed Americium-Beryllium (AmBe) Source by Inductively Coupled Plasma Mass Spectrometry

    SciTech Connect

    James Sommers; Marcos Jimenez; Mary Adamic; Jeffrey Giglio; Kevin Carney

    2009-12-01

    Two Americium-Beryllium neutron sources were dismantled, sampled (sub-sampled) and analyzed via inductively coupled plasma mass spectrometry (ICP-MS). Characteristics such as “age” since purification, actinide content, trace metal content and inter and intra source composition were determined. The “age” since purification of the two sources was determined to be 25.0 and 25.4 years, respectively. The systematic errors in the “age” determination were ± 4 % 2s. The amount and isotopic composition of U and Pu varied substantially between the sub-samples of Source 2 (n=8). This may be due to the physical means of sub-sampling or the way the source was manufactured. Source 1 was much more consistent in terms of content and isotopic composition (n=3 sub-samples). The Be-Am ratio varied greatly between the two sources. Source 1 had an Am-Be ratio of 6.3 ± 52 % (1s). Source 2 had an Am-Be ratio of 9.81 ± 3.5 % (1s). In addition, the trace element content between the samples varied greatly. Significant differences were determined between Source 1 and 2 for Sc, Sr, Y, Zr, Mo, Ba and W.

  14. 41 CFR 102-34.285 - Where can we obtain help in setting up a maintenance program?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Where can we obtain help in setting up a maintenance program? 102-34.285 Section 102-34.285 Public Contracts and Property... obtain help in setting up a maintenance program? For help in setting up a maintenance program,...

  15. 41 CFR 102-34.285 - Where can we obtain help in setting up a maintenance program?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Where can we obtain help in setting up a maintenance program? 102-34.285 Section 102-34.285 Public Contracts and Property... obtain help in setting up a maintenance program? For help in setting up a maintenance program,...

  16. 41 CFR 102-34.285 - Where can we obtain help in setting up a maintenance program?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Where can we obtain help in setting up a maintenance program? 102-34.285 Section 102-34.285 Public Contracts and Property... obtain help in setting up a maintenance program? For help in setting up a maintenance program,...

  17. 41 CFR 102-34.285 - Where can we obtain help in setting up a maintenance program?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Where can we obtain help in setting up a maintenance program? 102-34.285 Section 102-34.285 Public Contracts and Property... obtain help in setting up a maintenance program? For help in setting up a maintenance program,...

  18. Setting up a Grid: A Guide for Beginners by a Beginner

    NASA Technical Reports Server (NTRS)

    Welch, Clara

    2003-01-01

    A simple compute grid can be constructed for under $ 1,000 with 5 computers on a LAN for the purpose of video compression from captured digital video to MPEG file format. The process for setting up this grid will be covered in detail, including the required operating systems and hardware, the required globus software, and the required video capture and compression software. Pitfalls encountered will be discussed, and the approximate timeline for a motivated but uninformed beginner. The installation, configuration, and operation of additional software that is needed test, measure and otherwise verify that the grid components are functioning as "advertised", will also be presented. This is a true life account for setting up a grid based on instructions in Chapters 9 and 10 of Introduction to Grid Computing with Globus.

  19. Practical guidelines for setting up neurosurgery skills training cadaver laboratory in India.

    PubMed

    Suri, Ashish; Roy, Tara Sankar; Lalwani, Sanjeev; Deo, Rama Chandra; Tripathi, Manjul; Dhingra, Renu; Bhardwaj, Daya Nand; Sharma, Bhawani Shankar

    2014-01-01

    Though the necessity of cadaver dissection is felt by the medical fraternity, and described as early as 600 BC, in India, there are no practical guidelines available in the world literature for setting up a basic cadaver dissection laboratory for neurosurgery skills training. Hands-on dissection practice on microscopic and endoscopic procedures is essential in technologically demanding modern neurosurgery training where ethical issues, cost constraints, medico-legal pitfalls, and resident duty time restrictions have resulted in lesser opportunities to learn. Collaboration of anatomy, forensic medicine, and neurosurgery is essential for development of a workflow of cadaver procurement, preservation, storage, dissection, and disposal along with setting up the guidelines for ethical and legal concerns. PMID:25033845

  20. Setting up and using the autopatcher for automated intracellular neural recording in vivo

    PubMed Central

    Kodandaramaiah, Suhasa B.; Holst, Gregory L.; Wickersham, Ian R.; Singer, Annabelle C.; Franzesi, Giovanni Talei; McKinnon, Michael L.; Forest, Craig R.; Boyden, Edward S.

    2016-01-01

    Whole cell patch clamping in vivo is an important neuroscience technique that uniquely provides access to both supra-threshold spiking and sub-threshold synaptic events of single neurons in the brain. This article describes how to set up and use the autopatcher, a robot for automatically obtaining high yield and high quality whole cell patch clamp recordings in vivo. Following this protocol, a functional experimental rig for automated whole cell patch clamping can be set up in one week. High quality surgical preparation of mice takes approximately 1 hour, and each autopatching experiment can be carried out over periods lasting several hours. Autopatching should enable in vivo intracellular investigations to be accessible by a significant number of neuroscience labs, and enable labs already doing in vivo patch clamp to scale up their efforts by reducing training time for new lab members and increasing experimental durations by handling mentally intensive tasks automatically. PMID:26938115

  1. The Fantasio Set-Up (i): Description and Extension Towards Femto-Fantasio

    NASA Astrophysics Data System (ADS)

    Didriche, K.; Lauzin, C.; de Ghellinck, X.; Macko, P.; Rizopoulos, A.; Poucke, P. Van; Herman, M.; Kassi, S.

    2009-06-01

    We have built the FANTASIO set-up (for "Fourier trANsform, Tunable diode and quadrupole mAss spectrometers interfaced to a Supersonic expansIOn") to investigate jet-cooled molecules and dimers. The set-up will be described. New developments are on the way, to be illustrated by preliminary results. These include the doubling of the vacuum pumping system efficiency. They will also allow for a Femto OPO system to be used as a broadband, cavity enhanced absorption source to be interfaced to the supersonic expansion and to the high resolution FTIR instrument of FANTASIO. M. Herman, K. Didriche, D. Hurtmans, B. Kizil, P. Macko, A. Rizopoulos and P. Van Poucke, Mol. Phys., 105, 843 (2007).

  2. X-ray fluorescence (XRF) set-up with a low power X-ray tube.

    PubMed

    Gupta, Sheenu; Deep, Kanan; Jain, Lalita; Ansari, M A; Mittal, Vijay Kumar; Mittal, Raj

    2010-10-01

    The X-ray fluorescence set-up with a 100 W X-ray tube comprises a computer controlled system developed for remote operation and monitoring of tube and an adjustable stable 3D arrangement to procure variable excitation energies with low scattered background. The system was tested at different filament currents/anode voltages. The MDL of the set-up at 0.05-1.00 mA/4-12 kV is found approximately (1-100)ppm for K and L excitations and approximately (200-700)ppm for M excitations of elements and improves with filament current and anode voltage. Moreover, L measurements for Sm and Eu at five K X-ray energies of elements(Z=29-40) and analytical determination in some synthetic samples were undertaken. PMID:20570160

  3. Development of a grinding-specific performance test set-up.

    PubMed

    Olesen, C G; Larsen, B H; Andresen, E L; de Zee, M

    2015-01-01

    The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance. PMID:25367077

  4. Broadband short pulse measurement by autocorrelation with a sum-frequency generation set-up

    SciTech Connect

    Glotin, F.; Jaroszynski, D.; Marcouille, O.

    1995-12-31

    Previous spectral and laser pulse length measurements carried out on the CLIO FEL at wavelength {lambda}=8.5 {mu}m suggested that very short light pulses could be generated, about 500 fs wide (FWHM). For these measurements a Michelson interferometer with a Te crystal, as a non-linear detector, was used as a second order autocorrelation device. More recent measurements in similar conditions have confirmed that the laser pulses observed are indeed single: they are not followed by other pulses distant by the slippage length N{lambda}. As the single micropulse length is likely to depend on the slippage, more measurements at different wavelengths would be useful. This is not directly possible with our actual interferometer set-up, based on a phase-matched non-linear crystal. However, we can use the broadband non-linear medium provided by one of our users` experiments: Sum-Frequency Generation over surfaces. With such autocorrelation set-up, interference fringes are no more visible, but this is largely compensated by the frequency range provided. First tests at 8 {mu}m have already been performed to validate the technic, leading to results similar to those obtained with our previous Michelson set-up.

  5. Performance tests of external moderators of a PGNAA setup.

    PubMed

    Naqvi, A A; Fazal-ur-Rehman; Al-Jarallah, M I; Abu-Jarad, F; Maslehuddin, M

    2003-01-01

    Performance tests of external cylindrical moderators of an accelerator-based prompt gamma ray neutron activation analysis (PGNAA) setup have been carried out through thermal neutrons and prompt gamma-ray yield measurements. The PGNAA setup is to be used for analysis of cement samples. This study was conducted to investigate the effects of geometry of cylindrical moderator on yield of thermal neutrons and prompt gamma-rays for two different types of moderator assemblies. One of the moderators was to be used with a small sample and the other to be used with a large sample. Fast and thermal neutron yield was measured inside the sample volume as a function of the front moderator thickness as well as sample length. Neutron yield measurement was carried out at the King Fahd University of Petroleum and Minerals 350 keV pulsed beam accelerator using nuclear track detectors. The pulsed 200 keV deuteron beam with 5 ns pulse width and 31.25 kHz frequency was used to produce 2.8 MeV neutrons via D(d,n) reaction. Neutron yield measurements showed that the large sample moderator has a smaller yield of thermal neutrons as compared to the small sample moderator, which is in complete agreement with the results of Monte Carlo yield calculations of the thermal and fast neutrons from both the moderators. Finally, the prompt gamma-ray yield from a Portland cement sample was measured using the two moderators and was compared with each other. As predicted by Monte Carlo simulations, in spite of a smaller yield of thermal neutrons, the large sample moderator has a higher yield of prompt gamma-rays. PMID:12485660

  6. Load test set-up for the Airmass Sunburst Ultra-Light Aircraft

    NASA Technical Reports Server (NTRS)

    Krug, Daniel W.; Smith, Howard W.

    1993-01-01

    The purpose of this project was to set up, instrument, and test a Sunburst Ultra-Light aircraft. The intentions of the project were that the aircraft would need to be suspended from the test stand, leveled in the stand, the strain gauges tested and wired to the test equipment, and finally, the aircraft would be destroyed to obtain the failing loads. All jobs were completed, except for the destruction of the aircraft. This notebook shows the group's progress as these tasks were completed, and the following section attempts to explain the photographs in the notebook.

  7. Detection and dosimetry studies on the response of silicon diodes to an 241Am-Be source

    NASA Astrophysics Data System (ADS)

    Lotfi, Y.; Zaki Dizaji, H.; Abbasi Davani, F.

    2014-06-01

    Silicon diode detectors show potential for the development of an active personal dosimeter for neutron and photon radiation. Photons interact with the constituents of the diode detector and produce electrons. Fast neutrons interact with the constituents of the diode detector and converter, producing recoil nuclei and causing (n,α) and (n,p) reactions. These photon- and neutron-induced charged particles contribute to the response of diode detectors. In this work, a silicon pin diode was used as a detector to produce pulses created by photon and neutron. A polyethylene fast neutron converter was used as a recoil proton source in front of the detector. The total registered photon and neutron efficiency and the partial contributions of the efficiency, due to interactions with the diode and converter, were calculated. The results show that the efficiency of the converter-diode is a function of the incident photon and neutron energy. The optimized thicknesses of the converter for neutron detection and neutron dosimetry were found to be 1 mm and 0.1 mm respectively. The neutron records caused by the (n,α) and (n,p) reactions were negligible. The photon records were strongly dependent upon the energy and the depletion layer of the diode. The photons and neutrons efficiency of the diode-based dosimeter was calculated by the MCNPX code, and the results were in good agreement with experimental results for photons and neutrons from an 241Am-Be source.

  8. Set up of an automatic water quality sampling system in irrigation agriculture.

    PubMed

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2013-01-01

    We have developed a high-resolution automatic sampling system for continuous in situ measurements of stable water isotopic composition and nitrogen solutes along with hydrological information. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer (ProPS) for monitoring nitrate content and various water level sensors for hydrometric information. The automatic sampling system consists of different sampling stations equipped with pumps, a switch cabinet for valve and pump control and a computer operating the system. The complete system is operated via internet-based control software, allowing supervision from nearly anywhere. The system is currently set up at the International Rice Research Institute (Los Baños, The Philippines) in a diversified rice growing system to continuously monitor water and nutrient fluxes. Here we present the system's technical set-up and provide initial proof-of-concept with results for the isotopic composition of different water sources and nitrate values from the 2012 dry season. PMID:24366178

  9. Don't be afraid to set up your fish facility.

    PubMed

    McNabb, Adrian; Scott, Kirsty; Ochsenstein, Elke von; Seufert, Kirsten; Carl, Matthias

    2012-09-01

    Most young researchers leaving the safe haven of postdoctoral life for the unchartered territory of a PI position are confronted with a multitude of new tasks. For those using fish as their favorite model system, this often includes the daunting task of setting up and running a fish facility. New PIs are expected to know everything about this, and are even asked in job interviews about the precise details of the facility they anticipate using. Consulting other laboratories, talking to experienced facility managers, and sifting through books and web material will certainly help but can be enormously time consuming and at times frustrating. You will likely receive conflicting advice or encounter information that is overcomplicated and out of date. In this report, we summarize our collective experience of five different fish facilities, and outline what we consider to be the essential steps for setting up and running a successful facility. We also include valuable tips and tricks such as an optimized protocol for brine shrimp hatching. Our aim is to help researchers spend less time worrying about the technical aspects of their facility so that they can focus on their main job--research. PMID:22788540

  10. Setting up a Nuchal Translucency Clinic: What Radiologists Need to Know.

    PubMed

    Onyeacholem, Ifeanyi; Kleiner, Beth; Hull, Andrew D; Chibuk, Jason; Romine, Lorene; Anton, Tracy; Pretorius, Dolores H

    2016-03-01

    The purpose of this article was to discuss the process of setting up a nuchal translucency (NT) screening clinic in clinical practice, how to interpret the information in combination with other clinical tests, what to do if abnormal results are obtained, and to illustrate some of the fetal anomalies that are associated with an increased NT. The NT was initially implemented to predict the likelihood of a fetus with Down syndrome. Maternal age can be combined with fetal NT and maternal serum biochemistry (free β-hCG and PAPP-A) at 11 to 14 weeks to identify about 90% of affected fetuses. Setting up a clinic to perform the NT screening requires certified physicians and certified sonographers. Certification can be obtained for both physicians and sonographers through Nuchal Translucency Quality Review and Fetal Medicine Foundation. Cell-free DNA testing is now altering what our patients are choosing to evaluate fetuses at risk for chromosomal anomalies and congenital anomalies. Common pitfalls to performing, interpreting, and conveying results of the NT are illustrated in this article. Nasal bone measurement, fetal anatomy examination and fetal echocardiography are tools that add sensitivity to the detection of chromosomal abnormalities. Examples of fetal anomalies discovered during the NT screening are also illustrated. Screening for obstetric complications is an additional benefit to the NT clinic. PMID:25938550

  11. Test set up description and performances for HAWAII-2RG detector characterization at ESTEC

    NASA Astrophysics Data System (ADS)

    Crouzet, P.-E.; ter Haar, J.; de Wit, F.; Beaufort, T.; Butler, B.; Smit, H.; van der Luijt, C.; Martin, D.

    2012-07-01

    In the frame work of the European Space Agency's Cosmic Vision program, the Euclid mission has the objective to map the geometry of the Dark Universe. Galaxies and clusters of galaxies will be observed in the visible and near-infrared wavelengths by an imaging and spectroscopic channel. For the Near Infrared Spectrometer instrument (NISP), the state-of-the-art HAWAII-2RG detectors will be used, associated with the SIDECAR ASIC readout electronic which will perform the image frame acquisitions. To characterize and validate the performance of these detectors, a test bench has been designed, tested and validated. This publication describes the pre-tests performed to build the set up dedicated to dark current measurements and tests requiring reasonably uniform light levels (such as for conversion gain measurements). Successful cryogenic and vacuum tests on commercial LEDs and photodiodes are shown. An optimized feed through in stainless steel with a V-groove to pot the flex cable connecting the SIDECAR ASIC to the room temperature board (JADE2) has been designed and tested. The test set up for quantum efficiency measurements consisting of a lamp, a monochromator, an integrating sphere and set of cold filters, and which is currently under construction will ensure a uniform illumination across the detector with variations lower than 2%. A dedicated spot projector for intra-pixel measurements has been designed and built to reach a spot diameter of 5 μm at 920nm with 2nm of bandwidth [1].

  12. A digital holography set-up for 3D vortex flow dynamics

    NASA Astrophysics Data System (ADS)

    Lebon, Benoît; Perret, Gaële; Coëtmellec, Sébastien; Godard, Gilles; Gréhan, Gérard; Lebrun, Denis; Brossard, Jérôme

    2016-06-01

    In the present paper, a digital in-line holography (DIH) set-up, with a converging beam, is used to take three-dimensional (3D) velocity measurements of vortices. The vortices are formed periodically at the edges of a submerged horizontal plate submitted to regular waves. They take the form of vortex filaments that extend from side to side of the channel. They undergo strongly three-dimensional instability mechanisms that remain very complicated to characterize experimentally. The experiments are performed in a 10 × 0.3 × 0.3 m3 wave flume. The DIH set-up is performed using a modulated laser diode emitting at the wavelength of 640 nm and a lensless CCD camera. The beam crosses the channel side to side. To reveal the flow dynamics, 30-μm hydrogen bubbles are generated at the edge of the plate to serve as tracers. Their locations are recorded on the holograms multiple times to access the dynamics of the flow. This method leads to an accuracy in the order of 100 μm on the axial location. Those measurements have been validated with stereo-PIV measurements. A very good agreement is found on time-averaged velocity fields between the two techniques.

  13. The effect of different foot and hand set-up positions on backstroke start performance.

    PubMed

    de Jesus, Karla; de Jesus, Kelly; Abraldes, J Arturo; Mourão, Luis; Borgonovo-Santos, Márcio; Medeiros, Alexandre I A; Gonçalves, Pedro; Chainok, Phornpot; Fernandes, Ricardo J; Vaz, Mário A P; Vilas-Boas, João Paulo

    2016-11-01

    Foot and hand set-up position effects were analysed on backstroke start performance. Ten swimmers randomly completed 27 starts grouped in trials (n = 3) of each variation, changing foot (totally immersed, partially and totally emerged) and hand (lowest, highest horizontal and vertical) positioning. Fifteen cameras recorded kinematics, and four force plates collected hands and feet kinetics. Standardised mean difference and 95% confidence intervals were used. Variations with feet immersed have shown lower vertical centre of mass (CM) set-up position (0.16 m), vertical impulse exerted at the hands, horizontal and vertical impulse exerted at the feet (0.28, 0.41, 0.16 N/BW.s, respectively) than feet emerged with hands horizontal and vertically positioned. Most variations with feet partially emerged exhibited higher and lesser vertical impulse exerted at hands than feet immersed and emerged (e.g. vertical handgrip, 0.13, 0.15 N/BW.s, respectively). Variation with feet emerged and hands on the lowest horizontal handgrip depicted shorter horizontal (0.23, 0.26 m) and vertical CM positioning at flight (0.16, 0.15 m) than the highest horizontal and vertical handgrip, respectively. Start variations have not affected 15-m time. Variations with feet partially or totally emerged depicted advantages, but focusing on the entry and underwater biomechanics is relevant for a shorter start time. PMID:27268463

  14. Set Up of an Automatic Water Quality Sampling System in Irrigation Agriculture

    PubMed Central

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2014-01-01

    We have developed a high-resolution automatic sampling system for continuous in situ measurements of stable water isotopic composition and nitrogen solutes along with hydrological information. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer (ProPS) for monitoring nitrate content and various water level sensors for hydrometric information. The automatic sampling system consists of different sampling stations equipped with pumps, a switch cabinet for valve and pump control and a computer operating the system. The complete system is operated via internet-based control software, allowing supervision from nearly anywhere. The system is currently set up at the International Rice Research Institute (Los Baños, The Philippines) in a diversified rice growing system to continuously monitor water and nutrient fluxes. Here we present the system's technical set-up and provide initial proof-of-concept with results for the isotopic composition of different water sources and nitrate values from the 2012 dry season. PMID:24366178

  15. Three axis vector magnet set-up for cryogenic scanning probe microscopy.

    PubMed

    Galvis, J A; Herrera, E; Guillamón, I; Azpeitia, J; Luccas, R F; Munuera, C; Cuenca, M; Higuera, J A; Díaz, N; Pazos, M; García-Hernandez, M; Buendía, A; Vieira, S; Suderow, H

    2015-01-01

    We describe a three axis vector magnet system for cryogenic scanning probe microscopy measurements. We discuss the magnet support system and the power supply, consisting of a compact three way 100 A current source. We obtain tilted magnetic fields in all directions with maximum value of 5T along z-axis and of 1.2T for XY-plane magnetic fields. We describe a scanning tunneling microscopy-spectroscopy (STM-STS) set-up, operating in a dilution refrigerator, which includes a new high voltage ultralow noise piezodrive electronics and discuss the noise level due to vibrations. STM images and STS maps show atomic resolution and the tilted vortex lattice at 150 mK in the superconductor β-Bi2Pd. We observe a strongly elongated hexagonal lattice, which corresponds to the projection of the tilted hexagonal vortex lattice on the surface. We also discuss Magnetic Force Microscopy images in a variable temperature insert. PMID:25638089

  16. Setting up your own business. Facing the future as an entrepreneur.

    PubMed

    Brent, N J

    1990-01-01

    Other areas of setting up and running a business also are important to explore, especially if the business plans to use employees. You will become an employer, and you must be familiar with rules and regulations that include areas such as the employee's right to a safe workplace, worker's compensation laws, unemployment compensation laws and tax liabilities, antidiscrimination laws, and wage and tax laws. If independent contractors are going to be used, you must recognize that well-developed contracts are a necessity. If you are going to market a new product, consult with an attorney whose practice concentrates in trademark and patent law before the product is shared with others. Being well informed about the proposed business venture, not only before its establishment but as it develops and grows, can help you be in the best position to have a successful business. PMID:2301936

  17. Three axis vector magnet set-up for cryogenic scanning probe microscopy

    SciTech Connect

    Galvis, J. A.; Herrera, E.; Buendía, A.; Guillamón, I.; Vieira, S.; Suderow, H.; Azpeitia, J.; Luccas, R. F.; Munuera, C.; García-Hernandez, M.; and others

    2015-01-15

    We describe a three axis vector magnet system for cryogenic scanning probe microscopy measurements. We discuss the magnet support system and the power supply, consisting of a compact three way 100 A current source. We obtain tilted magnetic fields in all directions with maximum value of 5T along z-axis and of 1.2T for XY-plane magnetic fields. We describe a scanning tunneling microscopy-spectroscopy (STM-STS) set-up, operating in a dilution refrigerator, which includes a new high voltage ultralow noise piezodrive electronics and discuss the noise level due to vibrations. STM images and STS maps show atomic resolution and the tilted vortex lattice at 150 mK in the superconductor β-Bi{sub 2}Pd. We observe a strongly elongated hexagonal lattice, which corresponds to the projection of the tilted hexagonal vortex lattice on the surface. We also discuss Magnetic Force Microscopy images in a variable temperature insert.

  18. Specific heat measurement set-up for quench condensed thin superconducting films.

    PubMed

    Poran, Shachaf; Molina-Ruiz, Manel; Gérardin, Anne; Frydman, Aviad; Bourgeois, Olivier

    2014-05-01

    We present a set-up designed for the measurement of specific heat of very thin or ultra-thin quench condensed superconducting films. In an ultra-high vacuum chamber, materials of interest can be thermally evaporated directly on a silicon membrane regulated in temperature from 1.4 K to 10 K. On this membrane, a heater and a thermometer are lithographically fabricated, allowing the measurement of heat capacity of the quench condensed layers. This apparatus permits the simultaneous thermal and electrical characterization of successively deposited layers in situ without exposing the deposited materials to room temperature or atmospheric conditions, both being irreversibly harmful to the samples. This system can be used to study specific heat signatures of phase transitions through the superconductor to insulator transition of quench condensed films. PMID:24880383

  19. Setting up a regulatory compliance standard in today`s economy

    SciTech Connect

    Colbert, R.R.

    1994-12-31

    The economy, particularly in California, has forced the regulated community to begin streamlining and re-organization. The focus of industry today is survival. This translates into a lean staff with the dilemma of implementing and maintaining regulatory compliance on a low budget. In some instances financial resources have been absolved. Such circumstances allow innovation to excel to its highest peak. Setting up a compliance standard for an organization will allow the organization to effectively manage regulatory programs. Such a standard will define the regulatory obligations of the organization, particularly recognizing when you have exceeded the requirements. Compliance standards are intended to breed consistency among staff, while confirming that regulatory requirements have been met (particularly valuable in the mist of an external inspection).

  20. FTIR free-jet set-up for the high resolution spectroscopic investigation of condensable species

    NASA Astrophysics Data System (ADS)

    Georges, R.; Bonnamy, A.; Benidar, A.; Decroi, M.; Boissoles, J.

    2002-05-01

    An existing experimental set-up combining Fourier transform infrared (FTIR) spectroscopy and free-jet cooling has been modified significantly to allow high resolution studies of the spectrum of monomer species which are liquid under standard conditions. Evaporation of the liquid samples is controlled by a condenser apparatus which is described. A supersonic planar expansion issuing from a narrow aperture is preferred for its very high cooling rate. Such an expansion, probed with a pitot tube, has a zone of limited temperature gradient close to the nozzle exit. The continuum isentropic model appears well suited to describing the thermodynamic properties of the flow up to a high number of nozzle diameters downstream. High resolution spectra of benzene and methanol have been recorded in the 3 µm wavelength range, and their analysis demonstrates a well defined rotational temperature in the 20-25 K range.

  1. Error control in the set-up of stereo camera systems for 3d animal tracking

    NASA Astrophysics Data System (ADS)

    Cavagna, A.; Creato, C.; Del Castello, L.; Giardina, I.; Melillo, S.; Parisi, L.; Viale, M.

    2015-12-01

    Three-dimensional tracking of animal systems is the key to the comprehension of collective behavior. Experimental data collected via a stereo camera system allow the reconstruction of the 3d trajectories of each individual in the group. Trajectories can then be used to compute some quantities of interest to better understand collective motion, such as velocities, distances between individuals and correlation functions. The reliability of the retrieved trajectories is strictly related to the accuracy of the 3d reconstruction. In this paper, we perform a careful analysis of the most significant errors affecting 3d reconstruction, showing how the accuracy depends on the camera system set-up and on the precision of the calibration parameters.

  2. [Technical consideration of setting up a specification for human centrifuge evaluation of anti-G equipment].

    PubMed

    Zhang, C L; Geng, X C; Zhang, W X; Yan, G D; Chu, X

    1999-12-01

    Anti-G equipment needs to be evaluated using human centrifuge before further developed. However, there isn't a general specification for human centrifuge evaluation of anti-G equipment. From related literature and from our over thirty years experience in this area, we sum up to five aspect technical consideration below: human centrifuge, medical specification for using human in +Gz stress experiment, anti-G equipment experimental assembly, principle should be abided by during human centrifuge evaluation of anti-G equipment. We hope that the technical considerations mentioned in the paper should be helpful to the work of setting up a specification for human centrifuge evaluation anti-G equipment. After we have a specification, the research will be conducted orderly and the anti-G [correction of an-G] equipment will be developed sequentially. PMID:12434812

  3. Setting up a fee for service program for psychiatric liaison nurses.

    PubMed

    Platt-Koch, L; Gold, A; Jacobsma, B

    1990-01-01

    In the current health care climate, hospitals are under great pressure to find creative ways of preserving and generating revenue. As a result, all positions are routinely scrutinized for their value to the institution. Nurses have always been regarded as a major drain on the hospital's pocketbook, rather than as a revenue-generating resource. Because of their unique roles, liaison nurses provide many patient services which are third-party reimbursable. Practical guidelines for setting up a fee for service program are outlined together with the possible negative and positive repercussions of such a program. Enhanced job security and professional self-esteem may be offset by resistance from other disciplines and the possibility of a reduction in the volume of referrals. Although nurses who bill may face opposition from some groups, the ability to generate revenue is an important feature of this nursing role and is viewed as a strong asset by the institution. PMID:2268832

  4. Best practices sharing: Setting up a professional clinical research unit in India

    PubMed Central

    Divate, Uma; Das, Soma; Bhosale, Neelambari; Divate, Pathik

    2014-01-01

    The Drug Controller General of India has recently come up with very stringent laws to tighten the regulatory framework around clinical trials. One-way of improving the credibility of India and its researchers in the eyes of the regulators, sponsors and the general public is through professional site management team or setting up clinical research unit (CRU). The CRU acts as a bridge between the sponsor and the investigator. The CRU model has been better explained with the help of a good example of a clinical research institute. Since, a successful clinical trial needs high quality data, timeliness and clear communication between all parties, a professional CRU with a team of dedicated and trained professionals and infrastructure with written procedures and policies may be a solution to the pain and agony of poor site performance and investigator insufficiency and pressure. PMID:24551586

  5. Hopkinson pressure bar set-up for the measurement of Bauschinger effect under dynamic loading

    NASA Astrophysics Data System (ADS)

    Ruggiero, Andrew; Bonora, Nicola; Iannitti, Gianluca

    2013-06-01

    Metals and alloys show different stress-strain characteristics under reverse loading cycle (Bauschinger effect). The knowledge of the effective material response is important in impact dynamics where material is subjected to compression-tension loading as a result of stress wave propagation. In this paper an experimental set-up of the Hopkinson pressure bar to characterize the material response under dynamic loading cycle is presented. In the proposed configuration, in one single test, the sample is subjected to tension and compression loading with same absolute stress intensity and duration. Also this solution allows the possibility to select the load cycle sequence (tension-compression or compression-tension). Relationships to determine the stress, strain rate and strain from the elastic signals at the bars which are also effective for the second stress pulse, are presented. The method was verified with FEM and used to determine the Bauschinger effect for AISI 316L stainless steel.

  6. Reconstruction of relief by means of stereo-PIXE set-up for curved target

    NASA Astrophysics Data System (ADS)

    Gholami Hatam, E.

    2015-04-01

    This paper demonstrates an innovative simple technique to reconstruct the irregularities on the surfaces with curved geometry in stereo-PIXE (Particle Induced X-ray Emission) set-up. The method assumes that the local inclination of the topographical structure of the object results in X-ray yield asymmetries in two spectrometers mounted on both sides of the probing beam. The relief on the curved target could be quantitatively reconstructed by comparing the detected yield asymmetries and those calculated from a known non-structured cylindrical sample model of the target. The results of the relief reconstruction on a cone seashell at different radii close to its tip demonstrate that the method could reveal the relief in a region of the scanned area which is in the field of view of the two spectrometers.

  7. Setting up of a MicroKelvin refrigerator facility at TIFR

    NASA Astrophysics Data System (ADS)

    Naren, H. R.; Sannabhadti, R. S.; Kumar, Anil; Arolkar, V.; Ramakrishnan, S.

    2012-06-01

    In this note, we report the setting up of the first adiabatic nuclear demagnetization facility in India at the Tata Institute of Fundamental Research, Mumbai. We are able to cool 5 Kg of Copper down to 39 μK using this system. In addition we could maintain this temperature (39 μK) for more than 36 hours. Temperature was measured using Ruthenium oxide and Carbon (SPEER) resistance sensors in the range 4.2K-20 mK, Cerium Magnesium Nitrate (CMN) susceptibility sensors in the range 4.2 K-4 mK, and platinum (195Pt) NMR thermometry in the range 20 mK-39 μK.

  8. Quantum efficiency test set up performances for NIR detector characterization at ESTEC

    NASA Astrophysics Data System (ADS)

    Crouzet, P.-E.; Duvet, L.; De Wit, F.; Beaufort, T.; Blommaert, S.; Butler, B.; Van Duinkerken, G.; ter Haar, J.; Heijnen, J.; van der Luijt, K.; Smit, H.; Viale, T.

    2014-07-01

    The Payload Technology Validation Section (Future mission preparation Office) at ESTEC is in charge of specific mission oriented validation activities, for science and robotic exploration missions, aiming at reducing development risks in the implementation phase. These activities take place during the early mission phases or during the implementation itself. In this framework, a test set up to characterize the quantum efficiency of near infrared detectors has been developed. The first detector to be tested will an HAWAII-2RG detector with a 2.5μm cut off, it will be used as commissioning device in preparation to the tests of prototypes European detectors developed under ESA funding. The capability to compare on the same setup detectors from different manufacturers will be a unique asset for the future mission preparation office. This publication presents the performances of the quantum efficiency test bench to prepare measurements on the HAWAII-2RG detector. A SOFRADIR Saturn detector has been used as a preliminary test vehicle for the bench. A test set up with a lamp, chopper, monochromator, pinhole and off axis mirrors allows to create a spot of 1mm diameter between 700nm and 2.5μm.The shape of the beam has been measured to match the rms voltage read by the Merlin Lock -in amplifier and the amplitude of the incoming signal. The reference detectors have been inter-calibrated with an uncertainty up to 3 %. For the measurement with HAWAII-2RG detector, the existing cryostat [1] has been modified to adapt cold black baffling, a cold filter wheel and a sapphire window. An statistic uncertainty of +/-2.6% on the quantum efficiency on the detector under test measurement is expected.

  9. Barriers for setting up a pulmonary rehabilitation program in the Eastern Province of Saudi Arabia

    PubMed Central

    Alsubaiei, Mohammed E.; Cafarella, Paul A.; Frith, Peter A.; McEvoy, R. Doug; Effing, Tanja W.

    2016-01-01

    BACKGROUND: Pulmonary rehabilitation (PR) programs proven to be one of the most effective treatment options for respiratory diseases; yet, they are not well-established in hospitals in Saudi Arabia. AIM: To determine the main barriers for setting up PR programs in Saudi Arabia. METHODS: A cross-sectional study was conducted in the Eastern Province of Saudi Arabia. Health care providers involved in treatment of chronic obstructive pulmonary disease (COPD) patients were recruited from 22 general government hospitals. Data were collected using questionnaires: Full version if they had heard about PR before the study, and a short version if they had not heard about PR before. RESULTS: A total of 123 health care providers were recruited (physicians [n = 44], nurses [n = 49], and respiratory therapists/technicians [n = 30]). Only 3.2% of the recruited health care providers had heard about PR programs before. According to the health care providers, the main barriers for setting up PR programs were a lack of (1) hospital capacity (75.6%), (2) trained health care providers (72.4%), and (3) funds (48.0%). There were significant differences in barriers reported by the health care providers. Compared to physicians, nurses were more likely to nominate the PR costs as a barrier (18.0% vs. 38.8%; P < 0.05). CONCLUSION: There is a worrisome lack of knowledge regarding content and benefits of PR programs among Saudi health care providers treating COPD patients. These findings imply that improving awareness and increasing education of the health care providers regarding PR will be required before PR can be more widely implemented as an integral treatment modality for patients with COPD in Saudi Arabia. PMID:27168860

  10. Setting up a STAR Tier 2 Site at Golias/Prague Farm

    SciTech Connect

    Lauret, J.; Lauret, J.; Chaloupka, P.; Jakl, P.; Kapitan, J.; Zerola, M.

    2010-05-28

    High Energy Nuclear Physics (HENP) collaborations experience show that the computing resources available at a single site are often neither sufficient nor satisfy the need of remote collaborators eager to carry their analysis in the fastest and most convenient way. From latencies in the network connectivity to the lack of interactivity, work at distant computing centers is often inefficient. Having fully functional software stack on local resources is a strong enabler of science opportunities for any local group who can afford the time investment. The situation becomes more complex as vast amount of data are often needed to perform meaningful analysis. Prague's heavy-ions group participating in STAR experiment at RHIC has been a strong advocate of local computing as the most efficient means of data processing and physics analyses. To create an environment where science can freely thrive, a Tier 2 computing center was set up at a Regional Computing Center for Particle Physics called 'Golias'. It is the biggest farm in the Czech Republic fully dedicated for particle physics experiments. We report on our experience in setting up a fully functional Tier 2 center leveraging the minimal locally available human and financial resources. We discuss the solutions chosen to address storage space and analysis issues and the impact on the farms overall functionality. This includes a locally built STAR analysis framework, integration with a local DPM system (a cost effective storage solution), the influence of the availability and quality of the network connection to Tier 0 via a dedicated CESNET/ESnet link and the development of light-weight yet fully automated data transfer tools allowing the movement of entire datasets from BNL (Tier 0) to Golias (Tier 2). We will summarize the impact of the gained computing performance on the efficiency of the local physics group at offline physics analysis and show the feasibility of such a solution that can used by other groups as well.

  11. Set Up of an Automatic Water Quality Sampling System in Irrigation Agriculture

    NASA Astrophysics Data System (ADS)

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2014-05-01

    Climate change has already a large impact on the availability of water resources. Many regions in South-East Asia are assumed to receive less water in the future, dramatically impacting the production of the most important staple food: rice (Oryza sativa L.). Rice is the primary food source for nearly half of the World's population, and is the only cereal that can grow under wetland conditions. Especially anaerobic (flooded) rice fields require high amounts of water but also have higher yields than aerobic produced rice. In the past different methods were developed to reduce the water use in rice paddies, like alternative wetting and drying or the use of mixed cropping systems with aerobic (non-flooded) rice and alternative crops such as maize. A more detailed understanding of water and nutrient cycling in rice-based cropping systems is needed to reduce water use, and requires the investigation of hydrological and biochemical processes as well as transport dynamics at the field scale. New developments in analytical devices permit monitoring parameters at high temporal resolutions and at acceptable costs without much necessary maintenance or analysis over longer periods. Here we present a new type of automatic sampling set-up that facilitates in situ analysis of hydrometric information, stable water isotopes and nitrate concentrations in spatially differentiated agricultural fields. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer for monitoring nitrate content and various water level sensors for hydrometric information. The whole system is maintained with special developed software for remote control of the system via internet. We

  12. Setting up and functioning of an Emergency Medicine Department: Lessons learned from a preliminary study

    PubMed Central

    Asish, K; Suresh, Varun

    2016-01-01

    Background and Aims: Tertiary care teaching hospitals remain referral centres for victims of trauma and mass casualty. Often specialists from various disciplines manage these crowded casualty areas. These age old casualty areas are being replaced, throughout the country by Emergency Medicine Departments (EMDs), presumed to be better planned to confront a crisis. We aimed to gather basic data contributive in setting up of an EMD at a tertiary care teaching hospital from the lessons learned from functioning existent systems. Methods: This is primarily a questionnaire-based descriptive study at tertiary care referral centres across the country, which was purposively selected. The study models included one from a hospital without designated EMD and the other four from hospitals with established EMDs. Direct observation and focus group meetings with experienced informants at these hospitals contributed to the data. In the absence of a validated hospital preparedness assessment scale, comparison was done with regard to quantitative, qualitative and corroborative parameters using descriptive analysis. Results: The EMDs at best practice models were headed by specialist in Emergency Medicine assisted by organised staff, had protocols for managing mass casualty incident (MCI), separate trauma teams, ergonomic use of infrastructure and public education programmes. In this regard, these hospitals seemed well organised to manage MCIs and disasters. Conclusion: The observation may provide a preliminary data useful in setting up an EMD. In the absence of published Indian literature, this may facilitate further research in this direction. Anaesthesiologists, presently an approved Faculty in Emergency Medicine training can provide creative input with regard to its initial organisation and functioning, thus widening our horizons in a country where there is a severe dearth of trained emergency physicians. PMID:27013749

  13. Set-up uncertainty during postmastectomy radiotherapy with Segmented Photon Beams Technique

    PubMed Central

    Semaniak, Anna; Kukołowicz, Paweł

    2015-01-01

    Aim To verify the reproducibility of patients irradiated after mastectomy on the immobilization system designed and manufactured for our hospital and to compare the Internal Protocol (IP) with the modified-No Action Level Protocol. Background Application of forward IMRT techniques requires a good reproducibility of patient positioning. To minimize the set-up error, an effective immobilization system is important. Materials and methods The study was performed for two groups of 65 each. In the first group, portal images for anterior field were taken in 1–3 fractions and, subsequently, three times a week. In this group, the mNAL protocol was used. In the second group, the IP was used. The portal images from the anterior field and from the gantry 0 were taken during the 1–3 and 10 fractions. In both groups, image registration was performed off-line. For each group the systematic and random errors and PTV margin were calculated. Results In the first group the value of the population systematic errors and random errors were 1.6 ± 1.6 mm for the left–right, and 1.5 ± 1.7 mm for the cranial–caudal directions, respectively, 1.7 ± 1.3 mm, and 1.9 ± 1.3 mm for the second group. The PTV margins for the left–right and cranial–caudal directions were 5.1 and 4.9 mm for the first group and 5.4 and 6.4 mm for the second group. Conclusions For patients immobilized with our support device treated according to the mNAL protocol or IP, a good set-up reproducibility was obtained. Implementation of IP limits the number of required images. PMID:25949221

  14. Portable and low cost fluorescence set-up for in-situ screening of Ochratoxin A.

    PubMed

    Bueno, Diana; Mishra, Rupesh K; Hayat, Akhtar; Catanante, Gaëlle; Sharma, Vinay; Muñoz, Roberto; Marty, Jean-Louis

    2016-10-01

    The present article describes a portable and low cost fluorescence set-up designed and characterized for in-situ screening of Ochratoxin A (OTA) in cocoa samples at field settings. The sensing module (the set up) consists of a LED with the wavelength of 370-380nm and a color complementary metal oxide semiconductor (CMOS) micro-camera inbuilt at upright position of a black box to obtain an image of the sensing molecule. It allows the user to get an image of the sensing analytes under excitation conditions and process the image in order to predict the toxicity of the samples. The image capturing and processing of the system was based on the OTA concentration in the sample and analyzed data can be presented as RGB values. For each concentration of the OTA, the R, G, B co-ordinates were obtained and plotted to quantify actual OTA presents in the sample. Moreover, the system was tested for real sample analysis using cocoa contaminated with OTA. The system could detect OTA as low as 1.25ng/ml with the maximum recovery of 87.5% in cocoa samples. The OTA was extracted in 1% NaHCO3 and cleaned up using molecular imprinted polymer column (MIP). The method demonstrated a good linear range between 1.25 and 10ng/ml. The obtained results were cross validated using chromatographic method HPLC and also compared with commercially available fluorescence instrument. The developed fluorescence setup is simple, economical, and portable with added advantages of digital image processing. The system could be deployable to cocoa fields for monitoring of OTA in quick successions. It is noteworthy to mention that this is the first report of such portable fluorescence setup where, OTA sensing was explored. PMID:27474323

  15. Monitoring of D-T accelerator neutron output in a PGNAA system using silicon carbide detectors

    NASA Astrophysics Data System (ADS)

    Dulloo, Abdul R.; Ruddy, Frank H.; Seidel, John G.; Petrović, Bojan

    2001-07-01

    Silicon carbide (SiC) detectors are being employed to monitor the neutron output of the D-T accelerator in a pulsed Prompt Gamma Neutron Activation Analysis (PGNAA) system. Detection of the source neutrons relies on energetic neutron reactions in the detector material. Experimental testing has been performed to confirm that the detector response is caused by fast neutrons from the accelerator source. Modeling calculations have also been carried out to provide additional verification. Use of the SiC detectors in the PGNAA system is expected to assist in evaluating system performance as well as ensuring accurate data interpretation and analysis.

  16. Characterization of neutron flux spectra in the irradiation sites of a 37 GBq 241Am-Be isotopic source

    NASA Astrophysics Data System (ADS)

    Yücel, Haluk; Budak, Mustafa Guray; Karadag, Mustafa; Yüksel, Alptuğ Özer

    2014-11-01

    For the applicability of instrumental neutron activation analysis (NAA) technique, an irradiation unit with a 37 GBq 241Am-Be neutron source was installed at Institute of Nuclear Sciences of Ankara University. Design and configuration properties of the irradiation unit are described. It has two different sample irradiation positions, one is called site #1 having a pneumatic sample transfer system and the other is site #2 having a location for manual use. In order to characterize neutron flux spectra in the irradiation sites, the measurement results were obtained for thermal (Фth) and epithermal neutron fluxes (Фepi), thermal to epithermal flux ratio (f) and epithermal spectrum shaping factors (α) by employing cadmium ratios of gold (Au) and molybdenum (Mo) monitors. The activities produced in these foils were measured by using a p-type, 44.8% relative efficiency HPGe well detector. For the measured γ-rays, self-absorption and true coincidence summing effects were taken into account. Additionally, thermal neutron self-shielding and resonance neutron self-shielding effects were taken into account in the measured results. For characterization of site #1, the required parameters were found to be Фth = (2.11 ± 0.05) × 103 n cm-2 s-1, Фepi = (3.32 ± 0.17) × 101 n cm-2 s-1, f = 63.6 ± 1.5, α = 0.045 ± 0.009, respectively. Similarly, those parameters were measured in site #2 as Фth = (1.49 ± 0.04) × 103 n cm-2 s-1, Фepi = (2.93 ± 0.15) × 101 n cm-2 s-1, f = 50.9 ± 1.3 and α = 0.038 ± 0.008. The results for f-values indicate that good thermalization of fast neutrons on the order of 98% was achieved in both sample irradiation sites. This is because an optimum combination of water and paraffin moderator is used in the present configuration. In addition, the shielding requirements are met by using natural boron oxide powder (5.5 cm) and boron loaded paraffin layers against neutrons, and a 15 cm thick lead bricks against gamma-rays from source and its

  17. An expert system for histological typing and grading of invasive breast cancer. First set up.

    PubMed

    van Diest, P J; Belien, J A; Baak, J P

    1992-06-01

    This article describes the set up of a rule-based expert system for histologic typing and grading of invasive breast cancer, which is designed to be a user-friendly tool that may be helpful for teaching and to support diagnosis making. The system raises questions and offers fixed choices to the user (usually yes/no) until a histologic diagnosis can be made with reasonable probability or enough data are available to assign a grade. As to histologic typing, the expert system is able to make the following diagnoses: ductal carcinoma, lobular carcinoma, medullary carcinoma, colloidal carcinoma, tubular carcinoma, and invasive cribriform carcinoma. If the diagnosis "ductal carcinoma" is arrived, the system offers the option to assign a histologic grade to the lesion. A first evaluation of the system in 30 cases (five each of the different subtypes) with unequivocal diagnoses by two human experts showed that the system classified 29 of the tumours in the same way as the human experts. The discrepancy case was solved after adding one rule to the system. Ten cases where a discrepancy existed between the original diagnosis of a referring centre and a reviewing human expert were all classified by the expert system in the same way as the human expert. The expert system thus seems to perform well. Further plans for evaluating, modifying and expanding the system are disclosed. PMID:1329049

  18. Ultra-sensitive γ-ray spectroscopy set-up for investigating primordial lithium problem

    NASA Astrophysics Data System (ADS)

    Gervino, G.; Gustavino, C.; Trezzi, D.; Aliotta, M.; Anders, M.; Boeltzig, A.; Bemmerer, D.; Best, A.; Broggini, C.; Bruno, C.; Caciolli, A.; Cavanna, F.; Corvisiero, P.; Davinson, T.; Depalo, R.; DiLeva, A.; Elekes, Z.; Ferraro, F.; Formicola, A.; Fülöp, Zs.; Guglielmetti, A.; Gyürky, Gy.; Imbriani, G.; Junker, M.; Menegazzo, R.; Prati, P.; Scott, D. A.; Straniero, O.; Szücs, T.

    2016-07-01

    To precisely determine BBN 6Li production, the cross-section of the nuclear reaction 2H(α, γ)6Li must be directly measured within the astrophysical energy range of 30-400 keV. This measure requires an ultra-low γ-ray background in the experimental set-up. We have realized the conditions matching these very strict requirements at LUNA, the deep underground accelerator laboratory active in the INFN Gran Sasso National Laboratory (LNGS), Italy: the γ-ray spectrometer background has been reduced down to reach unmatched low levels, comparable to the good ones experienced in dedicated off-line underground ultra low γ counting rate. We present and discuss the γ-ray background reduction reached in the HpGe spectrometer, where most of the remaining γ-ray background seen in the spectra are coming from the energetic deuterons scattered in the gas target by the α beam. Thanks to the low neutron environmental background at LUNA, the effect of this weak flux of 2-3 MeV neutrons on HpGe detectors has been studied in details and the results are presented and discussed.

  19. Setting up a groundwater recharge model for an arid karst system using time lapse camera data

    NASA Astrophysics Data System (ADS)

    Schulz, Stephan; de Rooij, Gerrit H.; Michelsen, Nils; Rausch, Randolf; Siebert, Christian; Schüth, Christoph; Merz, Ralf

    2015-04-01

    Groundwater is the principal water resource in most dryland areas. Therefore, its replenishment rate is of great importance for water management. The amount of groundwater recharge depends on the climatic conditions, but also on the geological conditions, soil properties and vegetation. In dryland areas, outcrops of karst aquifers often receive enhanced recharge rates compared to other geological settings. Especially in areas with exposed karst features like sinkholes or open shafts rainfall accumulates in channels and discharges directly into the aquifer. Using the example of the As Sulb plateau in Saudi Arabia this study introduces a cost-effective and robust method for recharge monitoring and modelling in karst outcrops. The measurement of discharge of a small catchment (4.0 x 104 m2) into a sinkhole, and hence the direct recharge into the aquifer, was carried out with a time lapse camera observing a v-notch weir. During the monitoring period of two rainy seasons (autumn 2012 to spring 2014) four recharge events were recorded. Afterwards, recharge data as well as proxy data about the drying of the sediment cover are used to set up a conceptual water balance model. This model was run for 17 years (1971 to 1986 and 2012 to 2014). Simulation results show highly variable seasonal recharge-precipitation-ratios, which underlines the nonlinearity between recharge and precipitation in dryland areas. Besides the amount of precipitation this ratio is strongly influenced by the interannual distribution of rainfall events.

  20. Heavy ion elastic recoil detection analysis set up for electronic sputtering studies

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Avasthi, D. K.; Tripathi, A.; Kabiraj, D.; Sugathan, P.; Chaudhary, G. K.; Barua, P.

    2006-04-01

    Heavy ion elastic recoil detection analysis (ERDA) set up with a large solid angle (greater than or similar to 4.8 msr) Delta E - E position-sensitive telescope detector is developed at Inter University Accelerator Centre as a dedicated facility for the study of electronic sputtering of thin films under swift heavy ion (SHI) irradiation. The detector consists of a gas ionization chamber (Delta E ) and a solid-state surface barrier detector ( E ) housed in a same assembly. The electronic sputtering yield (atoms/ion) is determined by analyzing on-line fluence-dependent ERDA data obtained from a variety of thin films. Large erosion (> 10 5 atoms/ion) of carbon from a-C:H by 150 MeV Ag 13+ ions, evolution of nitrogen (greater than or similar to 880 atoms/ion) from copper nitride and depletion of oxygen (greater than or similar to 1000 atoms/ion) from copper oxide film under 200 MeV Au 15+ ion impact are studied and reported in this work. The electronic sputtering of these materials is discussed on the basis of the thermal spike model of SHI and solid interaction.

  1. Simulating the X-Ray Image Contrast to Set-Up Techniques with Desired Flaw Detectability

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2015-01-01

    The paper provides simulation data of previous work by the author in developing a model for estimating detectability of crack-like flaws in radiography. The methodology is being developed to help in implementation of NASA Special x-ray radiography qualification, but is generically applicable to radiography. The paper describes a method for characterizing X-ray detector resolution for crack detection. Applicability of ASTM E 2737 resolution requirements to the model are also discussed. The paper describes a model for simulating the detector resolution. A computer calculator application, discussed here, also performs predicted contrast and signal-to-noise ratio calculations. Results of various simulation runs in calculating x-ray flaw size parameter and image contrast for varying input parameters such as crack depth, crack width, part thickness, x-ray angle, part-to-detector distance, part-to-source distance, source sizes, and detector sensitivity and resolution are given as 3D surfaces. These results demonstrate effect of the input parameters on the flaw size parameter and the simulated image contrast of the crack. These simulations demonstrate utility of the flaw size parameter model in setting up x-ray techniques that provide desired flaw detectability in radiography. The method is applicable to film radiography, computed radiography, and digital radiography.

  2. Validation of a calibration set-up for radiosondes to fulfil GRUAN requirements

    NASA Astrophysics Data System (ADS)

    Sairanen, H.; Heinonen, M.; Högström, R.

    2015-10-01

    Interest in the precise measurement of water vapour in the upper-air is growing along with the consciousness of climate change. Because better knowledge of high altitude humidity levels improves the accuracy of climate models and weather forecasts, the Global Climate Observing System (GCOS) is putting more effort into the quality of these measurements. The GCOS established the Reference Upper-Air Network (GRUAN) and set the requirements for its measurements accuracy and traceability to the International System of Units (SI). To fulfil these requirements, improved radiosondes and methods to calibrate them are being developed. This paper presents a new calibration system for radiosondes based on mixing air flows from two independent dew-point generators. The system operates in the air temperature range down to  -80 °C. Our results show that the new calibration set-up is able to provide calibrations for radionsondes at the uncertainty level of 2% in terms of the water vapour mixing ratio as required by GRUAN. A complete calibration covering the whole temperature and humidity range lasts less than three days. Additionally, the apparatus provides an option to characterize the behaviour of a radiosonde in changing temperatures and water vapour concentrations.

  3. Carbon Ion Radiotherapy at the Gunma University Heavy Ion Medical Center: New Facility Set-up.

    PubMed

    Ohno, Tatsuya; Kanai, Tatsuaki; Yamada, Satoru; Yusa, Ken; Tashiro, Mutsumi; Shimada, Hirofumi; Torikai, Kota; Yoshida, Yukari; Kitada, Yoko; Katoh, Hiroyuki; Ishii, Takayoshi; Nakano, Takashi

    2011-01-01

    Carbon ion radiotherapy (C-ion RT) offers superior dose conformity in the treatment of deep-seated tumors compared with conventional X-ray therapy. In addition, carbon ion beams have a higher relative biological effectiveness compared with protons or X-ray beams. C-ion RT for the first patient at Gunma University Heavy Ion Medical Center (GHMC) was initiated in March of 2010. The major specifications of the facility were determined based on the experience of clinical treatments at the National Institute of Radiological Sciences (NIRS), with the size and cost being reduced to one-third of those at NIRS. The currently indicated sites of cancer treatment at GHMC are lung, prostate, head and neck, liver, rectum, bone and soft tissue. Between March 2010 and July 2011, a total of 177 patients were treated at GHMC although a total of 100 patients was the design specification during the period in considering the optimal machine performance. In the present article, we introduce the facility set-up of GHMC, including the facility design, treatment planning systems, and clinical preparations. PMID:24213124

  4. Carbon Ion Radiotherapy at the Gunma University Heavy Ion Medical Center: New Facility Set-up

    PubMed Central

    Ohno, Tatsuya; Kanai, Tatsuaki; Yamada, Satoru; Yusa, Ken; Tashiro, Mutsumi; Shimada, Hirofumi; Torikai, Kota; Yoshida, Yukari; Kitada, Yoko; Katoh, Hiroyuki; Ishii, Takayoshi; Nakano, Takashi

    2011-01-01

    Carbon ion radiotherapy (C-ion RT) offers superior dose conformity in the treatment of deep-seated tumors compared with conventional X-ray therapy. In addition, carbon ion beams have a higher relative biological effectiveness compared with protons or X-ray beams. C-ion RT for the first patient at Gunma University Heavy Ion Medical Center (GHMC) was initiated in March of 2010. The major specifications of the facility were determined based on the experience of clinical treatments at the National Institute of Radiological Sciences (NIRS), with the size and cost being reduced to one-third of those at NIRS. The currently indicated sites of cancer treatment at GHMC are lung, prostate, head and neck, liver, rectum, bone and soft tissue. Between March 2010 and July 2011, a total of 177 patients were treated at GHMC although a total of 100 patients was the design specification during the period in considering the optimal machine performance. In the present article, we introduce the facility set-up of GHMC, including the facility design, treatment planning systems, and clinical preparations. PMID:24213124

  5. Impedance measurement set-up based on off-the-shelf PXI modules

    NASA Astrophysics Data System (ADS)

    Pettersen, F. J.; Martinsen, Ø. G.; Grimnes, S.; Høgetveit, J. O.

    2010-04-01

    As bioimpedance measurements are being done in an increasing variety of measurands and environments, measurement equipment must be flexible in use and easy to handle for the researcher. Measurement equipment used today is excellent for a range of uses, but it is often bulky, heavy, and not very flexible. A new compact and flexible measurement set-up based on off-the-shelf modules is described. The system is based on commercially available PXI-modules, one module that may be custom made, and custom software. The basis of the system is a PXI chassis with a power supply unit. The chassis is equipped with a controller module running software controlling the system, a signal generator, and a multichannel digitizer. All of this is commercially available. Both a custom made and a commercially available impedance interfaces were used. A LabVIEW program is controlling the measurement system, and provides a user interface. The LabVIEW program handles necessary signal conditioning and calibration. The measurement system is capable of doing frequency response measurements at frequencies up to 15 MHz. In addition to the two normal voltage pick-up electrodes used in four-electrode measurements, this system has the possibility to use 5 extra voltage pick-up electrodes. This simplifies exploration of segmental impedance, anisotropy, reciprocity, etc.

  6. Use of 7Li(p,n) reaction as a neutron source in a PGNAA setup.

    PubMed

    Naqvi, A A; Nagadi, M M

    2005-03-01

    The performance of a 7Li(p,n) reaction-based Prompt Gamma Ray Neutron Activation Analysis (PGNAA) setup has been determined for analysis of Portland cement samples using Monte Carlo study. The calculations were carried out for a 7Li(p,n) reaction-based PGNAA setup with an external moderator similar to the one used in a previous 2.8 MeV neutrons-based PGNAA setup. The optimum values of geometry parameters of the 7Li(p,n) reaction-based setup are different from those of the 2.8 MeV neutrons-based setup resulting in better performance of the 7Li(p,n) reaction-based setup. The prompt gamma-ray yield from the 7Li(p,n) reaction-based setup is 60-70% higher than that from the 2.8 MeV neutrons-based setup. Although the performances of the 7Li(p,n) reaction-based setup is comparable with that of a previously studied 3H(p,n) reaction-based setup, yet performance of the 7Li(p,n) reaction-based setup is superior to that of the 3H(p,n) reaction-based setup because it has less radiation hazard due to utilization of non-radioactive neutron producing target. This study has provided a theoretical base for experimental test of a 7Li(p,n) reaction-based PGNAA setup. PMID:15607917

  7. Fast and thermal neutron intensity measurements at the KFUPM PGNAA setup

    NASA Astrophysics Data System (ADS)

    Al-Jarallah, M. I.; Naqvi, A. A.; Fazal-ur-Rehman; Abu-jarad, F.

    2002-10-01

    Fast and thermal neutron intensity distributions have been measured at an accelerator based prompt gamma ray neutron activation analysis (PGNAA) setup. The setup is built at the 350 keV accelerator laboratory of King Fahd University of Petroleum and Minerals (KFUPM). The setup is mainly designed to carry out PGNAA elemental analysis via thermal neutron capture. In this study relative intensity of fast and thermal neutrons was measured as a function of the PGNAA moderator assembly parameters using nuclear track detectors (NTDs). The relative intensity of the neutrons was measured inside the sample region as a function of front moderator thickness as well as sample length. Measurements were carried out at the KFUPM 350 keV accelerator using 2.8 MeV pulsed neutron beam from D(d,n) reaction. The pulsed deuteron beam with 5 ns pulse width and 30 kHz frequency was used to produce neutrons. Experimental results were compared with results of Monte Carlo design calculations of the PGNAA setup. A good agreement has been found between the experimental results and the calculations.

  8. Performance improvement of keV Neutrons-based PGNAA setups.

    PubMed

    Naqvi, A A; Abdelmonem, M S; Al-Misned, Ghada; Al-Ghamdi, Hanan

    2006-12-01

    The performance of keV neutrons based Prompt Gamma Ray Neutron Activation Analysis (PGNAA) setups have been observed to improve by enclosing its neutron source inside the moderator. The keV neutrons were produced via (7)Li(p,n) reaction and (3)H(p,n) reactions. For the two PGNAA setups, the maximum intensity of the prompt gamma-ray yield was observed for a 5cm long moderator with the neutron source positioned at a distance of 0.5cm from the moderator-end facing the sample. Due to enclosing the source inside the moderator, the prompt gamma-ray yield from the (7)Li(p,n) reaction and (3)H(p,n) reaction based PGNAA setups have increased by a factor of three as compared to that achieved from these setups with the source outside the moderator. This study provides a theoretical basis for the measurement of performance of (7)Li(p,n) reaction and the (3)H(p,n) reaction based PGNAA setups. PMID:16837206

  9. The identifiability analysis for setting up measuring campaigns in integrated water quality modelling

    NASA Astrophysics Data System (ADS)

    Freni, Gabriele; Mannina, Giorgio

    Identifiability analysis enables the quantification of the number of model parameters that can be assessed by calibration with respect to a data set. Such a methodology is based on the appraisal of sensitivity coefficients of the model parameters by means of Monte Carlo runs. By employing the Fisher Information Matrix, the methodology enables one to gain insights with respect to the number of model parameters that can be reliably assessed. The paper presents a study where identifiability analysis is used as a tool for setting up measuring campaigns for integrated water quality modelling. Particularly, by means of the identifiability analysis, the information about the location and the number of the monitoring stations in the integrated system required for assessing a specific group of model parameters were gained. The analysis has been applied to a real, partially urbanised, catchment containing two sewer systems, two wastewater treatment plants and a river. Several scenarios of measuring campaigns have been considered; each scenario was characterised by different monitoring station locations for the gathering of quantity and quality data. The results enabled us to assess the maximum number of model parameters quantifiable for each scenario i.e. for each data set. The methodology resulted to be a powerful tool for designing measuring campaign for integrated water quality modelling. Indeed, the crucial cross sections throughout the integrated wastewater system were detected optimizing both human and economic efforts in the gathering of field data. Further, a connection between the data set and the number of model parameters effectively assessable has been established leading to much more reliable model results.

  10. Epfl Lyisimeters Measurements Campaign Summer 2010:Set-Up and First Results

    NASA Astrophysics Data System (ADS)

    Ciocca, F.; Parlange, M.; Lunati, I.; van de Giesen, N.; Huwald, H.

    2010-09-01

    The goal of this experience is to evaluate the main contribution to heat and moisture fluxes into two different kinds of bare soils, one artificially realized and one real. The main hope is to definitely give an answer to the still open question of the effective role played by water vapor in the diffusion processes of heat and moisture, theoretically less efficient than liquid water of several order of magnitude but still considered the main responsible of unexpected high heat fluxes measured in many previous experiments. A refutation or a confirmation of the existence of the so discussed enhancement factor, or of a meaningful contribution by air advection, is also waited. To do this the six weighable lysimeters installed at the EPF Lausanne have been set up with a very accurate weighing system and used. Three of them filled up in the same way with natural sand silty soil coming from the site of Conthey (Sion - CH), filtered and put inside the tanks in homogeneous layer using a big sieve, without trying to preserve the original structure. For the remaining three an artificial porous mix, with textural properties as close as possible to those of the real soil, has been realized. Then a comparison between the real soil containing organic matter and the artificial sterile medium will be possible. A thick series of FDR and tensiometers has been installed in the upper part of each lysimeter and a new technique to measure volumetric water content using warmed optical fiber has been installed in two of them (one natural and one artificial). Incoming (general) and outcoming (for every lysimeter) short and longwave radiation have been measured, for consideration about energy balance. A comparison of the results obtained using a simple numerical model will also be realized.

  11. Bushmeat genetics: setting up a reference framework for the DNA typing of African forest bushmeat.

    PubMed

    Gaubert, Philippe; Njiokou, Flobert; Olayemi, Ayodeji; Pagani, Paolo; Dufour, Sylvain; Danquah, Emmanuel; Nutsuakor, Mac Elikem K; Ngua, Gabriel; Missoup, Alain-Didier; Tedesco, Pablo A; Dernat, Rémy; Antunes, Agostinho

    2015-05-01

    The bushmeat trade in tropical Africa represents illegal, unsustainable off-takes of millions of tons of wild game - mostly mammals - per year. We sequenced four mitochondrial gene fragments (cyt b, COI, 12S, 16S) in >300 bushmeat items representing nine mammalian orders and 59 morphological species from five western and central African countries (Guinea, Ghana, Nigeria, Cameroon and Equatorial Guinea). Our objectives were to assess the efficiency of cross-species PCR amplification and to evaluate the usefulness of our multilocus approach for reliable bushmeat species identification. We provide a straightforward amplification protocol using a single 'universal' primer pair per gene that generally yielded >90% PCR success rates across orders and was robust to different types of meat preprocessing and DNA extraction protocols. For taxonomic identification, we set up a decision pipeline combining similarity- and tree-based approaches with an assessment of taxonomic expertise and coverage of the GENBANK database. Our multilocus approach permitted us to: (i) adjust for existing taxonomic gaps in GENBANK databases, (ii) assign to the species level 67% of the morphological species hypotheses and (iii) successfully identify samples with uncertain taxonomic attribution (preprocessed carcasses and cryptic lineages). High levels of genetic polymorphism across genes and taxa, together with the excellent resolution observed among species-level clusters (neighbour-joining trees and Klee diagrams) advocate the usefulness of our markers for bushmeat DNA typing. We formalize our DNA typing decision pipeline through an expert-curated query database - DNA BUSHMEAT - that shall permit the automated identification of African forest bushmeat items. PMID:25264212

  12. Preliminary investigation on the design of biodegradable microparticles for ivermectin delivery: set up of formulation parameters.

    PubMed

    Dorati, Rosella; Genta, Ida; Colzani, Barbara; Tripodo, Giuseppe; Conti, Bice

    2015-01-01

    The aim was to design sterile biodegradable microparticulate drug delivery systems based on poly(dl-lactide) (PLA) and poly(ε-caprolactone) (PCL) and containing ivermectin (IVM), an antiparasitic drug, for subcutaneous administration in dogs. The drug delivery system should: (i) ensure a full 12-month protection upon single dose administration; (ii) be safe with particular attention regarding IVM dosage and its release, in order to prevent over dosage side effects. This preliminary work involves: polymer selection, evaluation of the effects of γ-irradiation on the polymers and IVM, investigation and set up of suitable microparticle preparation process and parameters, IVM-loaded microparticles in vitro release evaluation. Results of gel permeation chromatography analysis on the irradiated polymers and IVM mixtures showed that combination of IVM with the antioxidant α-tocopherol (TCP) reduces the damage extent induced by irradiation treatment, independently on the polymer type. Solvent evaporation process was successfully used for the preparation of PLA microparticles and appropriately modified; it was recognized as suitable for the preparation of PCL microparticles. Good process yields were achieved ranging from 76.08% to 94.72%; encapsulation efficiency was between 85.76% and 91.25%, independently from the polymer used. The type of polymer and the consequent preparation process parameters affected microparticle size that was bigger for PCL microparticles (480-800 µm) and solvent residual that was >500 ppm for PLA microparticles. In vitro release test showed significantly faster IVM release rates from PCL microparticles, with respect to PLA microparticles, suggesting that a combination of the polymers could be used to obtain the suitable drug release rate. PMID:24994001

  13. A Monte Carlo comparison of PGNAA system performance using 252Cf neutrons, 2.8-MeV neutrons and 14-MeV neutrons

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.

    2003-10-01

    Monte Carlo simulations were carried out to compare performance of a 252Cf neutron and a 14-MeV neutron-based prompt γ-ray neutron activation analysis (PGNAA) system with that of the 2.8-MeV neutron-based PGNAA system at King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia. Since the energy of neutron beam used in the KFUPM PGNAA system is very close to that produced by a DD neutron generator, performance comparison between a DD and a DT neutron generator-based PGNAA system is highly desired. For the sake of comparison, the calculations were carried out for the PGNAA system with geometry similar to the KFUPM PGNAA system. These calculations were required to determine improvement in performance of the KFUPM PGNAA system if its 2.8-MeV neutron source is replaced by a 252Cf neutron source or a 14-MeV neutron source. Results of the calculations revealed that the geometry of the 252Cf neutron and the 2.8-MeV neutron-based PGNAA system are not significantly different but the geometry of the 14-MeV neutron-based system is significantly different from that of the 2.8-MeV neutron-based PGNAA system. Accordingly, the prompt γ-ray yields from the 252Cf neutron and the 2.8-MeV neutron-based PGNAA system is comparable but prompt γ-ray yields from 14-MeV neutron-based PGNAA system are about three times smaller than that from the 2.8-MeV neutron-based PGNAA system. This study has shown that performance of the 252Cf neutron-based PGNAA system is comparable with that of the 2.8-MeV neutron-based PGNAA system but the performance of the 14-MeV neutron-based PGNAA system is poorer than that of the 2.8-MeV neutron-based PGNAA system.

  14. Influence of experimental set-up on the infiltration characteristics during managed aquifer recharge operation

    NASA Astrophysics Data System (ADS)

    Fichtner, Thomas; Vanzella de Melo, Julio Augusto; Stefan, Catalin

    2016-04-01

    The main focus during operation of managed aquifer recharge (MAR) is on clogging processes, specifically on the changes of infiltration capacities and degradation of infiltrated organic substances including vadose zone oxygen dynamics. Lab scale experiments are one opportunity to understand and characterize these processes under different drying and wetting cycles and infiltration rates. However, the multitude of assumptions and scale-related limitations of downscale investigations often lead to over- or underestimations, rendering their results useless when translated to field-like conditions. Therefore, the specific objective of this investigation is to compare the results obtained from two different experimental set-ups with different scales: a 3D, rectangular shaped, stainless steel lysimeter (1.5 x 1.0 x 1.0 m) with an infiltration basin installed in the centre of its surface and a 1D soil column (1m, ᴓ 0.15 m) with the infiltration over the complete column surface. The study focuses on the influence of the experimental setup conditions on the soil clogging, water flow pattern, oxygen dynamics and degradation of organic substances. The results should allow making statements about the suitability of these lab experiments for the investigation of processes taking place in the unsaturated soil zone during operation of MAR. Both experimental units were packed with the same soil and equipped with tensiometers, TDR-probes, oxygen probes and suction cups in two depths for the estimation of spatial and temporal distribution of soil moisture, oxygen and infiltrated substances. The lysimeter and the column were placed inside of a fully automatic climate tent, which facilitates the exact control of air temperature and humidity. The first results confirm that both infiltration units are suitable to simulate the clogging and the oxidation of easily degradable organic substances. However, the velocity of water transport is higher in the column compared with the lysimeter

  15. Different sedimentological and thermal evolution of three north-pyrenean basins during their set-up

    NASA Astrophysics Data System (ADS)

    Chelalou, Roman; Nalpas, Thierry; Bousquet, Romain; Lahfid, Abdeltif

    2015-04-01

    out to be good places where to study the evolution of passive margin analogue and also to be a good example where the sediments were metamorphosed during the basin set up.

  16. In vitro investigations of repulsion during laser lithotripsy using a pendulum set-up.

    PubMed

    Sroka, Ronald; Haseke, Nicolas; Pongratz, Thomas; Hecht, Volkmar; Tilki, Derya; Stief, Christian G; Bader, Markus Jürgen

    2012-05-01

    Ureteroscopic laser lithotripsy is a commonly used technique to treat ureteral calculi.The type of energy source used is one of the main influences of retrograd calculi propulsion. Using a momentum pendulum under-water set-up the induced momentum and the initial velocity were investigated. Pulsed laser light from three different clinically available laser systems, including a Ho:YAG laser, a frequency-doubled double-pulse (second harmonic generation, SHG) Nd:YAG laser and a flash-lamp pumped dye (FLPD) laser, were transmitted via flexible fibres of different core diameter to the front of the pendulum sinker. Single pulses at variable pulse energy, according to the clinical laser parameter settings, were applied to the target sinker, thus causing a repulsion-induced deflection which was documented by video recording. The maximum deflection was determined. Solving the differential equation of a pendulum gives the initial velocity, the laser-induced momentum and the efficiency of momentum transfer. The induced deflection as well as the starting velocity of the two short-duration pulsed laser systems (SHG Nd:YAG, FLPD) were similar (s (max) = 2-3.6 cm and v (0) = 150-200 mm/s, respectively), whereas both values were lower using the Ho:YAG laser with a long pulse duration (s (max) = 0.9--1.6 cm and v (0) = 60-105 mm/s, respectively). The momentum I induced by the Ho:YAG laser was only 50% and its transfer efficacy η (Repuls) was reduced to less than 5% of the values of the two short-pulsed laser systems. This investigation clearly showed the variable parts and amounts of repulsion using different pulsed lasers in an objective and reproducible manner. The momentum transfer efficiency could be determined without any physical friction problems. Further investigations are needed to compare stone fragmentation techniques with respect to laser repulsion and its clinical impact. PMID:22011742

  17. Intensity modulated radiation therapy for oropharyngeal cancer: the sensitivity of plan objectives and constraints to set-up uncertainty

    NASA Astrophysics Data System (ADS)

    Ploquin, Nicolas; Song, William; Lau, Harold; Dunscombe, Peter

    2005-08-01

    The goal of this study was to assess the impact of set-up uncertainty on compliance with the objectives and constraints of an intensity modulated radiation therapy protocol for early stage cancer of the oropharynx. As the convolution approach to the quantitative study of set-up uncertainties cannot accommodate either surface contours or internal inhomogeneities, both of which are highly relevant to sites in the head and neck, we have employed the more resource intensive direct simulation method. The impact of both systematic (variable from 0 to 6 mm) and random (fixed at 2 mm) set-up uncertainties on compliance with the criteria of the RTOG H-0022 protocol has been examined for eight geometrically complex structures: CTV66 (gross tumour volume and palpable lymph nodes suspicious for metastases), CTV54 (lymph node groups or surgical neck levels at risk of subclinical metastases), glottic larynx, spinal cord, brainstem, mandible and left and right parotids. In a probability-based approach, both dose-volume histograms and equivalent uniform doses were used to describe the dose distributions achieved by plans for two patients, in the presence of set-up uncertainty. The equivalent uniform dose is defined to be that dose which, when delivered uniformly to the organ of interest, will lead to the same response as the non-uniform dose under consideration. For systematic set-up uncertainties greater than 2 mm and 5 mm respectively, coverage of the CTV66 and CTV54 could be significantly compromised. Directional sensitivity was observed in both cases. Most organs at risk (except the glottic larynx which did not comply under static conditions) continued to meet the dose constraints up to 4 mm systematic uncertainty for both plans. The exception was the contra lateral parotid gland, which this protocol is specifically designed to protect. Sensitivity to systematic set-up uncertainty of 2 mm was observed for this organ at risk in both clinical plans.

  18. Medium-term cost-effectiveness of an automated non-invasive ventilation outpatient set-up versus a standard fixed level non-invasive ventilation inpatient set-up in obese patients with chronic respiratory failure: a protocol description

    PubMed Central

    Mandal, S; Arbane, G; Murphy, P; Elliott, M W; Janssens, J P; Pepin, J L; Muir, J F; Cuvelier, A; Polkey, M; Parkin, D; Douiri, A; Hart, N

    2015-01-01

    Introduction Obesity is an escalating issue, with an accompanying increase in referrals of patients with obesity-related respiratory failure. Currently, these patients are electively admitted to hospital for initiation of non-invasive ventilation (NIV), but it is unknown whether outpatient initiation is as effective as inpatient set-up. We hypothesise that outpatient set-up using an autotitrating NIV device will be more cost-effective than a nurse-led inpatient titration and set-up. Methods and analysis We will undertake a multinational, multicentre randomised controlled trial. Participants will be randomised to receive the usual inpatient set-up, which will include nurse-led initiation of NIV or outpatient set-up with an automated NIV device. They will be stratified according to the trial site, gender and previous use of NIV or continuous positive airway pressure. Assuming a 10% dropout rate, a total sample of 82 patients will be required. Cost-effectiveness will be evaluated using standard treatment costs and health service utilisation as well as health-related quality of life measures (severe respiratory insufficiency (SRI) and EuroQol-5 dimensions (EQ-5D)). A change in the SRI questionnaire will be based on the analysis of covariance adjusting for the baseline measurements between the two arms of patients. Ethics and dissemination This study has been approved by the Westminster National Research Ethics Committee (11/LO/0414) and is the trial registered on the UKCRN portfolio. The trial is planned to start in January 2015 with publication of the trial results in 2017. Trial registration number ISRCTN 51420481. PMID:25908673

  19. Analysis of Major and Minor Elements in Meteorites Dhofar 020, Sikhote Alin and North West Africa 2909 By PGNAA and SEM-EDS

    NASA Astrophysics Data System (ADS)

    Adur, B.; Netravali, S.; Damle, M.; Mali, H. B.

    2014-09-01

    Meteorites Dhofar 020, Sikhote Alin and NWA 2909 have been analyzed using PGNAA and SEM-EDS. Elements H and B have been detected in all three meteorites by PGNAA. No compositional analysis has so far been done on particular fragment Dhofar 020 and NWA 2909.

  20. A feasibility study of a coincidence counting approach for PGNAA applications

    PubMed

    Gardner; Mayo; El-Sayyed; Metwally; Zheng; Poezart

    2000-10-01

    Prompt gamma-ray nutron activation analysis (PGNAA) has an inherently low signal-to-noise (S/N) ratio primarily because of the large background (noise) associated with it. Most elements emit a significant fraction of their prompt gamma rays in coincidence with one or more other prompt gamma rays. This paper reports on initial efforts to use coincidence counting in PGNAA to significantly reduce the several sources of background and thereby increase the S/N ratio. An added benefit is the elimination of the often dominant hydrogen prompt gamma-ray spectrum which emits only a single prompt gamma ray with an energy of 2.223 MeV. Preliminary results are given for both in situ bulk analysis applications with a 252Cf neutron source and for nuclear reactor thermal neutron beam applications for small laboratory samples. PMID:11003486

  1. Monte Carlo simulation of pulse pile-up effect in gamma spectrum of a PGNAA system

    NASA Astrophysics Data System (ADS)

    Mowlavi, Ali Asghar; Hadizadeh Yazdi, Mohammad Hadi

    2011-12-01

    We have applied a pile-up Monte Carlo simulation code on gamma spectrum of a prompt gamma neutron activation analysis (PGNAA) system. The code has been run in nonparalyzable mode for a specific geometry of a PGNAA system with 241Am-9Be source and NaI(Tl) detector to obtain the distortion due to “pile-up” in the pulse height of gamma spectrum. The results show that the main background in the nitrogen region of interest (ROI) is due to two pile-ups. We have also evaluated the variation of count rate and total photon sampling over the Monte Carlo spectra. At high count rates, not only the nitrogen ROI but also carbon ROI, and hydrogen peak are disturbed strongly. Comparison between the results of simulations and the experimental spectra has shown a good agreement. The code could be used for other source setups and different gamma detection systems.

  2. The optimization of gamma spectra processing in prompt gamma neutron activation analysis (PGNAA)

    NASA Astrophysics Data System (ADS)

    Pinault, Jean-Louis; Solis, Jose

    2009-04-01

    The uncertainty of the elemental analysis is one of the major factors governing the utility of on-line Prompt Gamma Neutron Activation Analysis (PGNAA) in the blending and sorting of bulk materials. In this paper, a general method applicable to Gamma spectra processing is presented and applied to PGNAA in mineral industry. Based on the Fourier transform of spectra and their de-correlation in the Fourier space (the improvement of the conditioning of the correlation matrix), processing of overlapping of characteristic peaks minimizes the propagation of random errors, which optimizes the accuracy and decreases the detection limits of elemental analyses. In comparison with classical methods based on the linear combinations of relevant regions of spectra the improvement may be considerable, especially when several elements are interfering. The method is applied to four case stories covering both borehole logging and on-line analysis on conveyor belt of raw materials.

  3. Response of a PGNAA setup for pozzolan-based cement concrete specimens.

    PubMed

    Naqvi, A A; Garwan, M A; Maslehuddin, M; Nagadi, M M; Al-Amoudi, O S B; Raashid, M

    2010-01-01

    Pozzolanic materials are added to Portland cement concrete to increase its durability, particularly corrosion-resistance. In this study the elemental composition of a pozzolanic cement concrete was measured non-destructively utilizing an accelerator-based Prompt Gamma Ray Neutron Activation Analysis (PGNAA) setup. The optimum size of the pozzolanic cement concrete specimen was obtained through Monte Carlo simulations. The simulation results were experimentally verified through the gamma-ray yield measurement from the pozzolanic cement concrete specimens as a function of their radii. The concentration of the pozzolanic material in the cement concrete specimens was evaluated by measuring gamma-ray yield for calcium and iron from pozzolanic cement concrete specimens containing 5-80 wt% pozzolan. A good agreement was noted between the experimental values and the Monte Carlo simulation results, indicating an excellent response of the KFUPM accelerator-based PGNAA setup for pozzolan based concrete. PMID:19819713

  4. 350 keV accelerator based PGNAA setup to detect nitrogen in bulk samples

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Al-Matouq, Faris A.; Khiari, F. Z.; Gondal, M. A.; Rehman, Khateeb-ur; Isab, A. A.; Raashid, M.; Dastageer, M. A.

    2013-11-01

    Nitrogen concentration was measured in explosive and narcotics proxy material, e.g. anthranilic acid, caffeine, melamine, and urea samples, bulk samples through thermal neutron capture reaction using 350 keV accelerator based prompt gamma ray neutron activation (PGNAA) setup. Intensity of 2.52, 3.53-3.68, 4.51, 5.27-5.30 and 10.38 MeV prompt gamma rays of nitrogen from the bulk samples was measured using a cylindrical 100 mm×100 mm (diameter×height ) BGO detector. Inspite of interference of nitrogen gamma rays from bulk samples with capture prompt gamma rays from BGO detector material, an excellent agreement between the experimental and calculated yields of nitrogen gamma rays has been obtained. This is an indication of the excellent performance of the PGNAA setup for detection of nitrogen in bulk samples.

  5. Setting Up Letters Using the AppleWorks Word Processor Subprogram and Apple IIe or GS Computers.

    ERIC Educational Resources Information Center

    Schlenker, Richard M.

    This manual is a "how to" training device for setting up letter word processing files using the AppleWorks program with an Apple IIe or Apple IIGS computer which has a Duodisk or two disk drives and an 80-column card. The manual provides step-by-step directions, and includes 16 figures depicting the computer screen at the various stages of word…

  6. Setting up a Low-Cost Lab Management System for a Multi-Purpose Computing Laboratory Using Virtualisation Technology

    ERIC Educational Resources Information Center

    Mok, Heng Ngee; Lee, Yeow Leong; Tan, Wee Kiat

    2012-01-01

    This paper describes how a generic computer laboratory equipped with 52 workstations is set up for teaching IT-related courses and other general purpose usage. The authors have successfully constructed a lab management system based on decentralised, client-side software virtualisation technology using Linux and free software tools from VMware that…

  7. Here's How We Set Up a Staff-Run Day-Care Center for Our Own Kids.

    ERIC Educational Resources Information Center

    Ancell, Allen; Haugen, Merry

    1986-01-01

    School systems can set up staff-run day care centers for their own children, deriving planning ideas from the many corporations that perceive meeting employees' child-care needs as an asset. Planning involves employee child-care scheduling, cost estimates, and program development. (CJH)

  8. Clinical Profile of Children and Adolescents Attending the Behavioural Paediatrics Unit OPD in a Tertiary Care Set up

    ERIC Educational Resources Information Center

    Jayaprakash, R.

    2012-01-01

    Background: There are limited studies on the clinical profile of children attending child guidance clinic under Paediatric background. Aims: To study clinical profile of Children & adolescents attending the Behavioural Paediatrics Unit (BPU) OPD under department of Paediatrics in a tertiary care set up. Methods: Monthly average turnover in the OPD…

  9. IRMA-2 at SOLEIL: a set-up for magnetic and coherent scattering of polarized soft x-rays

    NASA Astrophysics Data System (ADS)

    Sacchi, M.; Popescu, H.; Gaudemer, R.; Jaouen, N.; Avila, A.; Delaunay, R.; Fortuna, F.; Maier, U.; Spezzani, C.

    2013-03-01

    We have designed, built and tested a new instrument for soft x-ray scattering experiments. IRMA-2 is a UHV set-up for elastic and coherent scattering experiments developed at the SEXTANTS beamline of the SOLEIL synchrotron. Applications will be in the field of solid state physics, with emphasis on the investigation of the magnetic properties of artificially structured materials.

  10. Physics of recent applications of PGNAA for on-line analysis of bulk minerals

    NASA Astrophysics Data System (ADS)

    Gozani, Tsahi

    1985-01-01

    In the last few years the coal, cement and other mineral industries are slowly but steadily coming to realize the potential economical, technological and environmental benefits from using nuclar and especially PGNAA techniques. This realization along with the great efforts and the technological developments of the last decade culminated in a successful production and operation of the last decade culminated in a successful production and operation of a family of on-line analyzer under the name ``Nucoalyzer.''

  11. Application of PGNAA for bulk coal samples in a 4pi geometry.

    PubMed

    Borsaru, M; Jecny, Z

    2001-03-01

    A 4pi geometry bulk coal analyser using the Prompt gamma neutron activation analysis (PGNAA) technique was tested in the laboratory. The volume of the bulk samples was 270 litres. A 1.5 microg 252Cf neutron source and a 75 mm x 35 mm dia BGO detector were used for the measurements. The ash, Fe, Si and Al content of coal were determined with good accuracy. PMID:11214889

  12. Precision assessment of model-based RSA for a total knee prosthesis in a biplanar set-up.

    PubMed

    Trozzi, C; Kaptein, B L; Garling, E H; Shelyakova, T; Russo, A; Bragonzoni, L; Martelli, S

    2008-10-01

    Model-based Roentgen Stereophotogrammetric Analysis (RSA) was recently developed for the measurement of prosthesis micromotion. Its main advantage is that markers do not need to be attached to the implants as traditional marker-based RSA requires. Model-based RSA has only been tested in uniplanar radiographic set-ups. A biplanar set-up would theoretically facilitate the pose estimation algorithm, since radiographic projections would show more different shape features of the implants than in uniplanar images. We tested the precision of model-based RSA and compared it with that of the traditional marker-based method in a biplanar set-up. Micromotions of both tibial and femoral components were measured with both the techniques from double examinations of patients participating in a clinical study. The results showed that in the biplanar set-up model-based RSA presents a homogeneous distribution of precision for all the translation directions, but an inhomogeneous error for rotations, especially internal-external rotation presented higher errors than rotations about the transverse and sagittal axes. Model-based RSA was less precise than the marker-based method, although the differences were not significant for the translations and rotations of the tibial component, with the exception of the internal-external rotations. For both prosthesis components the precisions of model-based RSA were below 0.2 mm for all the translations, and below 0.3 degrees for rotations about transverse and sagittal axes. These values are still acceptable for clinical studies aimed at evaluating total knee prosthesis micromotion. In a biplanar set-up model-based RSA is a valid alternative to traditional marker-based RSA where marking of the prosthesis is an enormous disadvantage. PMID:18635360

  13. PGNAA system preliminary design and measurement of In-Hospital Neutron Irradiator for boron concentration measurement.

    PubMed

    Zhang, Zizhu; Chong, Yizheng; Chen, Xinru; Jin, Congjun; Yang, Lijun; Liu, Tong

    2015-12-01

    A prompt gamma neutron activation analysis (PGNAA) system has been recently developed at the 30-kW research reactor In-Hospital Neutron Irradiator (IHNI) in Beijing. Neutrons from the specially designed thermal neutron beam were used. The thermal flux of this beam is 3.08×10(6) cm(-2) s(-1) at a full reactor power of 30 kW. The PGNAA system consists of an n-type high-purity germanium (HPGe) detector of 40% efficiency, a digital spectrometer, and a shielding part. For both the detector shielding part and the neutron beam shielding part, the inner layer is composed of (6)Li2CO3 powder and the outer layer lead. The boron-10 sensitivity of the PGNAA system is approximately 2.5 cps/ppm. Two calibration curves were produced for the 1-10 ppm and 10-50 ppm samples. The measurement results of the control samples were in accordance with the inductively coupled plasma atomic emission spectroscopy (ICP-AES) results. PMID:26242556

  14. Neutron fluence rate measurements in a PGNAA 208-liter drum assay system using silicon carbide detectors

    NASA Astrophysics Data System (ADS)

    Dulloo, A. R.; Ruddy, F. H.; Seidel, J. G.; Lee, S.; Petrović, B.; McIlwain, M. E.

    2004-01-01

    Pulsed prompt gamma neutron activation analysis (PGNAA) is being implemented for the nondestructive assay (NDA) of mercury, cadmium and lead in containers of radioactive waste. A PGNAA prototype system capable of assaying 208-liter (55-gallon) drums has already been built and demonstrated. As part of the evaluation of this system, the thermal neutron fluence rate distribution in a drum containing a combustible waste surrogate was measured during PGNAA runs using a silicon carbide neutron detector. The fast charge-collection time of this detector type enabled the investigation of the neutron kinetics at various locations within the matrix during and between pulses of the system's 14-MeV neutron source. As expected, the response of a SiC detector equipped with a lithium-6 fluoride layer is dominated by thermal neutron-induced events between pulses. The measurement results showed that the thermal neutron fluence rate is relatively uniform over a radial depth of several centimeters in the matrix region that contributes a significant fraction of the prompt gamma radiation incident on the system's photon detector.

  15. Heavy metals detection in sediments using PGNAA method.

    PubMed

    Da-Qian, Hei; Wen-Bao, Jia; Zhou, Jiang; Can, Cheng; Jia-Tong, Li; Hong-Tao, Wang

    2016-06-01

    A prompt gamma ray neutron activation analysis detection system was developed to detect the heavy metals in sediments by using an (241)Am-Be neutron source and BGO detector. The samples containing cadmium and mercury were used to test the performance of setup. The linear relationship between prompt gamma ray counts and the concentrations was studied. The results showed the counts of the prompt gamma rays from cadmium do not increase linearly with its concentrations, while the prompt gamma ray counts from Hg vary nearly linearly with the concentrations, due to the neutron self-shielding. Then a method was used to correct the effect and the non-linearly response was restored after the correction. And the minimum detectable concentration of Cd and Hg were 52.8 (at 8.484MeV) and 81.6 (at 5.967MeV) ppm, respectively. PMID:27015649

  16. Superconducting quantum interference devices based set-up for probing current noise and correlations in three-terminal devices.

    PubMed

    Pfeffer, A H; Kaviraj, B; Coupiac, O; Lefloch, F

    2012-11-01

    We have implemented a new experimental set-up for precise measurements of current fluctuations in three-terminal devices. The system operates at very low temperatures (30 mK) and is equipped with three superconducting quantum interference devices (SQUIDs) as low noise current amplifiers. A SQUID input coil is connected to each terminal of a sample allowing the acquisition of time-dependent current everywhere in the circuit. From these traces, we can measure the current mean value, the noise, and cross-correlations between different branches of a device. In this paper, we present calibration results of noise and cross-correlations obtained using low impedance macroscopic resistors. From these results, we can extract the noise level of the set-up and show that there are no intrinsic correlations due to the measurement scheme. We also studied noise and correlations as a function of a dc current and estimated the electronic temperature of various macroscopic resistors. PMID:23206098

  17. Superconducting quantum interference devices based set-up for probing current noise and correlations in three-terminal devices

    SciTech Connect

    Pfeffer, A. H.; Kaviraj, B.; Coupiac, O.; Lefloch, F.

    2012-11-15

    We have implemented a new experimental set-up for precise measurements of current fluctuations in three-terminal devices. The system operates at very low temperatures (30 mK) and is equipped with three superconducting quantum interference devices (SQUIDs) as low noise current amplifiers. A SQUID input coil is connected to each terminal of a sample allowing the acquisition of time-dependent current everywhere in the circuit. From these traces, we can measure the current mean value, the noise, and cross-correlations between different branches of a device. In this paper, we present calibration results of noise and cross-correlations obtained using low impedance macroscopic resistors. From these results, we can extract the noise level of the set-up and show that there are no intrinsic correlations due to the measurement scheme. We also studied noise and correlations as a function of a dc current and estimated the electronic temperature of various macroscopic resistors.

  18. A confocal set-up for micro-XRF and XAFS experiments using diamond-anvil cells.

    PubMed

    Wilke, Max; Appel, Karen; Vincze, Laszlo; Schmidt, Christian; Borchert, Manuela; Pascarelli, Sakura

    2010-09-01

    A confocal set-up is presented that improves micro-XRF and XAFS experiments with high-pressure diamond-anvil cells (DACs). In this experiment a probing volume is defined by the focus of the incoming synchrotron radiation beam and that of a polycapillary X-ray half-lens with a very long working distance, which is placed in front of the fluorescence detector. This set-up enhances the quality of the fluorescence and XAFS spectra, and thus the sensitivity for detecting elements at low concentrations. It efficiently suppresses signal from outside the sample chamber, which stems from elastic and inelastic scattering of the incoming beam by the diamond anvils as well as from excitation of fluorescence from the body of the DAC. PMID:20724788

  19. Monitoring of spectroscopic changes of a single trapped fission yeast cell by using a Raman tweezers set-up

    NASA Astrophysics Data System (ADS)

    Başar, G.; Kın, S.

    2008-10-01

    We demonstrate an improvement of the sensitivity of a Raman tweezers set-up, which combines optical tweezers with Raman spectroscopy. The system was tested by taking the Raman spectrum of a 4.6 μm diameter polystyrene sphere trapped in an aqueous solution. The improvement of sensitivity of the set-up was achieved by adjusting the trap depth for maximum signal to noise ratio (SNR). The maximum SNR was obtained by investigating the Raman peak of a trapped polystyrene sphere at 1001 cm -1 according to trap depth. With this system, a single trapped living Schizosaccharomyces Pombe yeast cell was sensitively monitored by taking the kinetic Raman spectra for more than 2 h. The relative intensity decrease in amide I and amide III bands, frequency increase in amide I band together with alterations in tyrosine marker band around 850 cm -1 was observed, which indicates alterations in the hydration state of protein by time progressing.

  20. Cone beam CT with zonal filters for simultaneous dose reduction, improved target contrast and automated set-up in radiotherapy

    NASA Astrophysics Data System (ADS)

    Moore, C. J.; Marchant, T. E.; Amer, A. M.

    2006-05-01

    Cone beam CT (CBCT) using a zonal filter is introduced. The aims are reduced concomitant imaging dose to the patient, simultaneous control of body scatter for improved image quality in the tumour target zone and preserved set-up detail for radiotherapy. Aluminium transmission diaphragms added to the CBCT x-ray tube of the Elekta Synergy™ linear accelerator produced an unattenuated beam for a central 'target zone' and a partially attenuated beam for an outer 'set-up zone'. Imaging doses and contrast noise ratios (CNR) were measured in a test phantom for transmission diaphragms 12 and 24 mm thick, for 5 and 10 cm long target zones. The effect on automatic registration of zonal CBCT to conventional CT was assessed relative to full-field and lead-collimated images of an anthropomorphic phantom. Doses along the axis of rotation were reduced by up to 50% in both target and set-up zones, and weighted dose (two thirds surface dose plus one third central dose) was reduced by 10-20% for a 10 cm long target zone. CNR increased by up to 15% in zonally filtered CBCT images compared to full-field images. Automatic image registration remained as robust as that with full-field images and was superior to CBCT coned down using lead-collimation. Zonal CBCT significantly reduces imaging dose and is expected to benefit radiotherapy through improved target contrast, required to assess target coverage, and wide-field edge detail, needed for robust automatic measurement of patient set-up error.

  1. Evaluation of RSA set-up from a clinical biplane fluoroscopy system for 3D joint kinematic analysis

    PubMed Central

    BONANZINGA, TOMMASO; SIGNORELLI, CECILIA; BONTEMPI, MARCO; RUSSO, ALESSANDRO; ZAFFAGNINI, STEFANO; MARCACCI, MAURILIO; BRAGONZONI, LAURA

    2016-01-01

    Purpose dinamic roentgen stereophotogrammetric analysis (RSA), a technique currently based only on customized radiographic equipment, has been shown to be a very accurate method for detecting three-dimensional (3D) joint motion. The aim of the present work was to evaluate the applicability of an innovative RSA set-up for in vivo knee kinematic analysis, using a biplane fluoroscopic image system. To this end, the Authors describe the set-up as well as a possible protocol for clinical knee joint evaluation. The accuracy of the kinematic measurements is assessed. Methods the Authors evaluated the accuracy of 3D kinematic analysis of the knee in a new RSA set-up, based on a commercial biplane fluoroscopy system integrated into the clinical environment. The study was organized in three main phases: an in vitro test under static conditions, an in vitro test under dynamic conditions reproducing a flexion-extension range of motion (ROM), and an in vivo analysis of the flexion-extension ROM. For each test, the following were calculated, as an indication of the tracking accuracy: mean, minimum, maximum values and standard deviation of the error of rigid body fitting. Results in terms of rigid body fitting, in vivo test errors were found to be 0.10±0.05 mm. Phantom tests in static and kinematic conditions showed precision levels, for translations and rotations, of below 0.1 mm/0.2° and below 0.5 mm/0.3° respectively for all directions. Conclusions the results of this study suggest that kinematic RSA can be successfully performed using a standard clinical biplane fluoroscopy system for the acquisition of slow movements of the lower limb. Clinical relevance a kinematic RSA set-up using a clinical biplane fluoroscopy system is potentially applicable and provides a useful method for obtaining better characterization of joint biomechanics. PMID:27602352

  2. Evaluation of different set-up error corrections on dose-volume metrics in prostate IMRT using CBCT images.

    PubMed

    Hirose, Yoshinori; Nakamura, Mitsuhiro; Tomita, Tsuneyuki; Kitsuda, Kenji; Notogawa, Takuya; Miki, Katsuhito; Nakamura, Kiyonao; Ishigaki, Takashi

    2014-09-01

    We investigated the effect of different set-up error corrections on dose-volume metrics in intensity-modulated radiotherapy (IMRT) for prostate cancer under different planning target volume (PTV) margin settings using cone-beam computed tomography (CBCT) images. A total of 30 consecutive patients who underwent IMRT for prostate cancer were retrospectively analysed, and 7-14 CBCT datasets were acquired per patient. Interfractional variations in dose-volume metrics were evaluated under six different set-up error corrections, including tattoo, bony anatomy, and four different target matching groups. Set-up errors were incorporated into planning the isocenter position, and dose distributions were recalculated on CBCT images. These processes were repeated under two different PTV margin settings. In the on-line bony anatomy matching groups, systematic error (∑) was 0.3 mm, 1.4 mm, and 0.3 mm in the left-right, anterior-posterior (AP), and superior-inferior directions, respectively. ∑ in three successive off-line target matchings was finally comparable with that in the on-line bony anatomy matching in the AP direction. Although doses to the rectum and bladder wall were reduced for a small PTV margin, averaged reductions in the volume receiving 100% of the prescription dose from planning were within 2.5% under all PTV margin settings for all correction groups, with the exception of the tattoo set-up error correction only (≥ 5.0%). Analysis of variance showed no significant difference between on-line bony anatomy matching and target matching. While variations between the planned and delivered doses were smallest when target matching was applied, the use of bony anatomy matching still ensured the planned doses. PMID:24820094

  3. Evaluation of different set-up error corrections on dose–volume metrics in prostate IMRT using CBCT images

    PubMed Central

    Hirose, Yoshinori; Nakamura, Mitsuhiro; Tomita, Tsuneyuki; Kitsuda, Kenji; Notogawa, Takuya; Miki, Katsuhito; Nakamura, Kiyonao; Ishigaki, Takashi

    2014-01-01

    We investigated the effect of different set-up error corrections on dose–volume metrics in intensity-modulated radiotherapy (IMRT) for prostate cancer under different planning target volume (PTV) margin settings using cone-beam computed tomography (CBCT) images. A total of 30 consecutive patients who underwent IMRT for prostate cancer were retrospectively analysed, and 7–14 CBCT datasets were acquired per patient. Interfractional variations in dose–volume metrics were evaluated under six different set-up error corrections, including tattoo, bony anatomy, and four different target matching groups. Set-up errors were incorporated into planning the isocenter position, and dose distributions were recalculated on CBCT images. These processes were repeated under two different PTV margin settings. In the on-line bony anatomy matching groups, systematic error (∑) was 0.3 mm, 1.4 mm, and 0.3 mm in the left–right, anterior–posterior (AP), and superior–inferior directions, respectively. ∑ in three successive off-line target matchings was finally comparable with that in the on-line bony anatomy matching in the AP direction. Although doses to the rectum and bladder wall were reduced for a small PTV margin, averaged reductions in the volume receiving 100% of the prescription dose from planning were within 2.5% under all PTV margin settings for all correction groups, with the exception of the tattoo set-up error correction only (≥5.0%). Analysis of variance showed no significant difference between on-line bony anatomy matching and target matching. While variations between the planned and delivered doses were smallest when target matching was applied, the use of bony anatomy matching still ensured the planned doses. PMID:24820094

  4. Assessment of the neutron emission anisotropy factor of a sealed AmBe source by means of measurements and Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Loreti, S.; Pietropaolo, A.

    2015-10-01

    The neutron emission anisotropy factor of a sealed Americium-Beryllium source is experimentally determined and compared to Monte Carlo simulations. The measurements were done at the Italian Institute for Metrology of Ionizing Radiations using a long counter neutron detector and a "X.3" type AmBe sealed neutron source. Experimental data are compared to simulations performed with the MCNP code where the precise structure of the source is taken into account starting from its technical design. The contributions of the single structural parts are described to point out the effective sources of the emission anisotropy.

  5. Comparison of DD, DT and Cf-252 neutron excitation of light and medium mass nuclei for field PGNAA applications

    NASA Astrophysics Data System (ADS)

    Seabury, E. H.; Blackburn, B. W.; Chichester, D. L.; Wharton, C. J.; Caffrey, A. J.

    2007-08-01

    Prompt Gamma Ray Neutron activation analysis can offer significant cost and safety advantages in the identification of explosives and toxic chemicals. As an example, the US military examined over a thousand suspect chemical munitions with Idaho National Laboratory's PINS Chemical Assay System last year. PGNAA requires, of course, a neutron source to excite the atomic nuclei of the item under test via neutron capture and inelastic neutron scattering reactions and the choice of neutron source can drastically affect PGNAA system performance. We have carried out Monte Carlo and laboratory experiments comparing DD, DT and Cf-252 neutrons incident on light and medium mass chemical elements, toward optimizing the design of future neutron-generator-based PGNAA systems for field use. We report the excitation of (n, γ) and (n, n‧) gamma rays from these elements by each type of neutron source.

  6. Extraction of pure thermal neutron beam for the proposed PGNAA facility at the TRIGA research reactor of AERE, Savar, Bangladesh

    NASA Astrophysics Data System (ADS)

    Alam, Sabina; Zaman, M. A.; Islam, S. M. A.; Ahsan, M. H.

    1993-10-01

    A study on collimators and filters for the design of a spectrometer for prompt gamma neutron activation analysis (PGNAA) at one of the radial beamports of the TRIGA Mark II reactor at AERE, Savar has been carried out. On the basis of this study a collimator and a filter have been designed for the proposed PGNAA facility. Calculations have been done for measuring neutron flux at various positions of the core of the reactor using the computer code TRIGAP. Gamma dose in the core of the reactor has also been measured experimentally using TLD technique in the present work.

  7. The effect of systematic set-up deviations on the absorbed dose distribution for left-sided breast cancer treated with respiratory gating

    NASA Astrophysics Data System (ADS)

    Edvardsson, A.; Ceberg, S.

    2013-06-01

    The aim of this study was 1) to investigate interfraction set-up uncertainties for patients treated with respiratory gating for left-sided breast cancer, 2) to investigate the effect of the inter-fraction set-up on the absorbed dose-distribution for the target and organs at risk (OARs) and 3) optimize the set-up correction strategy. By acquiring multiple set-up images the systematic set-up deviation was evaluated. The effect of the systematic set-up deviation on the absorbed dose distribution was evaluated by 1) simulation in the treatment planning system and 2) measurements with a biplanar diode array. The set-up deviations could be decreased using a no action level correction strategy. Not using the clinically implemented adaptive maximum likelihood factor for the gating patients resulted in better set-up. When the uncorrected set-up deviations were simulated the average mean absorbed dose was increased from 1.38 to 2.21 Gy for the heart, 4.17 to 8.86 Gy to the left anterior descending coronary artery and 5.80 to 7.64 Gy to the left lung. Respiratory gating can induce systematic set-up deviations which would result in increased mean absorbed dose to the OARs if not corrected for and should therefore be corrected for by an appropriate correction strategy.

  8. Quality improvement process to assess tattoo alignment, set-up accuracy and isocentre reproducibility in pelvic radiotherapy patients

    PubMed Central

    Elsner, Kelly; Francis, Kate; Hruby, George; Roderick, Stephanie

    2014-01-01

    Introduction This quality improvement study tested three methods of tattoo alignment and isocentre definition to investigate if aligning lateral tattoos to minimise pitch, roll and yaw decreased set-up error, and if defining the isocentre using the lateral tattoos for cranio-caudal (CC) position improved isocentre reproducibility. The study population was patients receiving curative external beam radiotherapy (EBRT) for prostate cancer. The results are applicable to all supine pelvic EBRT patients. Methods The three sequential cohorts recruited 11, 11 and 10 patients respectively. A data set of 20 orthogonal pairs of electronic portal images (EPI) was acquired for each patient. EPIs were matched offline to digitally reconstructed radiographs. In cohort 1, lateral tattoos were adjusted to minimise roll. The anterior tattoo was used to define the isocentre. In cohort 2, lateral tattoos were aligned to minimise roll and yaw. Isocentre was defined as per cohort 1. In cohort 3, lateral tattoos were aligned as per cohort 2 and the anterior tattoo was adjusted to minimise pitch. Isocentre was defined by the lateral tattoos for CC position and the anterior tattoo for the left–right position. Results Cohort 3 results were superior as CC systematic and random set-up errors reduced from −1.3 mm to −0.5 mm, and 3.1 mm to 1.4 mm respectively, from cohort 1 to cohort 3. Isocentre reproducibility also improved from 86.7% to 92.1% of treatment isocentres within 5 mm of the planned isocentre. Conclusion The methods of tattoo alignment and isocentre definition in cohort 3 reduced set-up errors and improved isocentre reproducibility. PMID:25598978

  9. Totomatix: a novel automatic set-up to control diurnal, diel and long-term plant nitrate nutrition

    PubMed Central

    Adamowicz, Stéphane; Le Bot, Jacques; Huanosto Magaña, Ruth; Fabre, José

    2012-01-01

    Background Stand-alone nutritional set-ups are useful tools to grow plants at defined nutrient availabilities and to measure nutrient uptake rates continuously, in particular that for nitrate. Their use is essential when the measurements are meant to cover long time periods. These complex systems have, however, important drawbacks, including poor long-term reliability and low precision at high nitrate concentration. This explains why the information dealing with diel dynamics of nitrate uptake rate is scarce and concerns mainly young plants grown at low nitrate concentration. Scope The novel system detailed in this paper has been developed to allow versatile use in growth rooms, greenhouses or open fields at nitrate concentrations ranging from a few micro- to several millimoles per litres. The system controls, at set frequencies, the solution nitrate concentration, pH and volumes. Nitrate concentration is measured by spectral deconvolution of UV spectra. The main advantages of the set-up are its low maintenance (weekly basis), an ability to diagnose interference or erroneous analyses and high precision of nitrate concentration measurements (0·025 % at 3 mm). The paper details the precision of diurnal nitrate uptake rate measurements, which reveals sensitivity to solution volume at low nitrate concentration, whereas at high concentration, it is mostly sensitive to the precision of volume estimates. Conclusions This novel set-up allows us to measure and characterize the dynamics of plant nitrate nutrition at high temporal resolution (minutes to hours) over long-term experiments (up to 1 year). It is reliable and also offers a novel method to regulate up to seven N treatments by adjusting the daily uptake of test plants relative to controls, in variable environments such as open fields and glasshouses. PMID:21985796

  10. The Semi-opened Infrastructure Model (SopIM): A Frame to Set Up an Organizational Learning Process

    NASA Astrophysics Data System (ADS)

    Grundstein, Michel

    In this paper, we introduce the "Semi-opened Infrastructure Model (SopIM)" implemented to deploy Artificial Intelligence and Knowledge-based Systems within a large industrial company. This model illustrates what could be two of the operating elements of the Model for General Knowledge Management within the Enterprise (MGKME) that are essential to set up the organizational learning process that leads people to appropriate and use concepts, methods and tools of an innovative technology: the "Ad hoc Infrastructures" element, and the "Organizational Learning Processes" element.

  11. Estimation of low-level neutron dose-equivalent rate by using extrapolation method for a curie level Am-Be neutron source.

    PubMed

    Li, Gang; Xu, Jiayun; Zhang, Jie

    2014-10-22

    Neutron radiation protection is an important research area because of the strong radiation biological effect of neutron field. The radiation dose of neutron is closely related to the neutron energy, and the connected relationship is a complex function of energy. For the low-level neutron radiation field (e.g. the Am-Be source), the commonly used commercial neutron dosimeter cannot always reflect the low-level dose rate, which is restricted by its own sensitivity limit and measuring range. In this paper, the intensity distribution of neutron field caused by a curie level Am-Be neutron source was investigated by measuring the count rates obtained through a (3)He proportional counter at different locations around the source. The results indicate that the count rates outside of the source room are negligible compared with the count rates measured in the source room. In the source room, (3)He proportional counter and neutron dosimeter were used to measure the count rates and dose rates respectively at different distances to the source. The results indicate that both the count rates and dose rates decrease exponentially with the increasing distance, and the dose rates measured by a commercial dosimeter are in good agreement with the results calculated by the Geant4 simulation within the inherent errors recommended by ICRP and IEC. Further studies presented in this paper indicate that the low-level neutron dose equivalent rates in the source room increase exponentially with the increasing low-energy neutron count rates when the source is lifted from the shield with different radiation intensities. Based on this relationship as well as the count rates measured at larger distance to the source, the dose rates can be calculated approximately by the extrapolation method. This principle can be used to estimate the low level neutron dose values in the source room which cannot be measured directly by a commercial dosimeter. PMID:25464188

  12. Investigation of the PGNAA using the LaBr3 scintillation detector.

    PubMed

    Favalli, A; Mehner, H-C; Ciriello, V; Pedersen, B

    2010-01-01

    The Joint Research Centre of the European Commission develops instrumentation for detection of hazardous materials. In relation to this a new experimental facility was constructed for research into methods applying the detection of characteristic gamma rays subsequent to neutron irradiation. This includes the detection of prompt gamma rays from neutron inelastic scattering and neutron capture. For this purpose the device employs LaBr(3) scintillation detectors. The paper investigates the applicability of the LaBr(3) scintillation detector to PGNAA. PMID:19884018

  13. Effect of silica fume addition on the PGNAA measurement of chlorine in concrete.

    PubMed

    Naqvi, A A; Maslehuddin, M; Garwan, M A; Nagadi, M M; Al-Amoudi, O S B; Raashid, M; Khateeb-ur-Rehman

    2010-03-01

    Pozzolanic materials, such as fly ash (FA), silica fume (SF), and blast furnace slag (BFS) are added to Portland cement in concrete to prevent reinforcement steel corrosion in concrete. Further preventive measure against reinforcement steel corrosion require monitoring of chloride salts concentration in concrete using non-destructive techniques, such as the prompt gamma-ray neutron activation analysis (PGNAA) technique. Due to interferences between gamma-rays from chlorine and calcium in PGNAA technique, detection limit of chlorine in concrete strongly depends upon calcium concentration in concrete. SF mainly contains silica and its addition to cement concrete reduces overall concentration of calcium in concrete. This may result in an improvement in detection limit of chlorine in SF-based concrete in PGNAA studies. Particularly for chlorine detection using 6.11 and 6.62 MeV prompt gamma-rays that strongly interfere with 6.42 MeV prompt gamma-rays from calcium. In this study, SF was added to Portland cement to prevent concrete reinforcement steel from corrosion. The chlorine concentration in SF cement concrete specimens containing 0.2-3.0 wt% chlorine was measured through yield of 1.16, 1.95, 6.11, 6.62, 7.41, 7.79, and 8.58 MeV chlorine gamma-rays using PGNAA technique. An excellent agreement was noted between the experimental yield of the prompt gamma-rays and the gamma-ray yield calculated through the Monte Carlo simulations. Further the minimum detectable concentration (MDC) of chlorine in SF cement concrete was calculated and compared with the MDC values of chlorine in plain concrete and concrete mixed with fly ash cement. The MDC of chlorine in SF-based concrete through 6.11 MeV, and 6.62 MeV chlorine gamma-rays was found to be improved as compared to those in plain concrete and concrete mixed with fly ash cement. PMID:20042342

  14. To Set Up Norms for Drug Safety and Inspection: To Guarantee Administrative Sufficiency and Avoid Regulators from Being Wrongly Punished.

    PubMed

    Xuan, Qingsheng; Dong, Zuojun; Shao, Mingli

    2015-09-01

    Currently, as there is no systematic norm or standard for drug safety and inspection, it cannot be judged whether the regulatory authority or regulators have fulfilled their administrative responsibilities entirely or not, when a drug safety-related incident occurs. And there is a probability that some may even be wrongly punished. In this study, we have analyzed the risk of not having appropriate norms in place and also put forward recommendations for the government or the regulatory authorities to set up norms to be fulfilled for drug safety and inspection issues. This, on one hand, could provide a basic guideline for the regulatory authorities and regulators to improve their professional levels and administrative acumen and on the other hand, it could also provide a baseline for society to judge whether the regulatory authorities and regulators have fulfilled their responsibilities correctly and thereby also help prevent regulators from being mistakenly punished. This study proposes that a systematic and functional norm for drug safety and inspection could be set up relating to the determination of the responsibilities of regulatory authorities and scope of various inspections, number and frequency of inspections, number and qualifications of regulators, handling of inspection results, inspection records, and disciplinary codes for inspectors. This study also puts forward suggestions on who should be responsible for drafting the norms and what are the factors that need to be considered while formulating the norms. PMID:27352264

  15. Setting up of in-vacuum PIXE system for direct elemental analysis of thick solid environmental samples.

    PubMed

    Rihawy, M S; Ismail, I M; Halloum, D

    2016-04-01

    Experimental set-up, development, characterization, and calibration of an in-vacuum PIXE system at the tandem accelerator facility of the Atomic Energy Commission of Syria (AECS) is described. The PIXE system calibration involved experimental characterization of the X-ray detector parameters and careful determination of the H-values that control dependence of the detector solid angle with the X-ray energies and correct imperfect values of the detector efficiency. Setting up of an electron flood gun to compensate charge built up and utilization of a beam profile monitor to perform indirect measurement of the beam charge, provide a direct PIXE measurement of thick insulating samples in-vacuum. The PIXE system has been subsequently examined to verify its ability to perform direct PIXE measurements on geological materials. A combination of minimum sample preparation procedures and specific experimental conditions applied enables simple and accurate elemental analysis. Elemental concentrations of several elements heavier than sodium in different reference geological samples, at about 5-10% absolute accuracy for most elements, have been determined. Comprehensive discussion of the obtained elemental concentration values, for most elements of visible X-ray peaks in the PIXE spectra, has been considered. PMID:26803668

  16. Effect of picosecond laser induced cavitation bubbles generated on Au targets in a nanoparticle production set-up

    NASA Astrophysics Data System (ADS)

    Tiberi, M.; Simonelli, A.; Cristoforetti, G.; Marsili, P.; Giammanco, F.; Giorgetti, E.

    2013-03-01

    This work is aimed at an analysis of the influence on the efficiency of nanoparticle production of a cavitation bubble (CB), which forms during the laser ablation process in high-fluence regime. The CB is produced on an Au metal target immersed in water by 1064 nm ps Nd:YAG laser pulses at different fluences. Its time-space evolution is monitored by a shadowgraphic set-up, while the Au nanoparticles production rate is tagged by the growth of the plasmon resonance, which is detected by measuring shot-by-shot the UV-Vis absorbance. We analyze the dependence of bubble size on the experimental parameters. Our results appear of interest to enhance the nanoparticle production efficiency in a liquid medium.

  17. A low frequency electrical test set-up for the reliability assessment of capacitive RF MEMS switches

    NASA Astrophysics Data System (ADS)

    van Spengen, W. Merlijn; Puers, Robert; Mertens, Robert; DeWolf, Ingrid

    2003-09-01

    The reliability and lifetime testing of capacitive RF MEMS switches one by one at the intended signal frequency range (GHz) is very expensive because RF equipment is monopolized for a large amount of time. Testing a statistically significant number of devices in this way is therefore impractical. Furthermore testing the switches in a harsh environment is difficult. We have developed a new, low frequency measurement set-up to address these issues. In this paper, the principle of operation is described, as are measurements revealing the following failure modes of RF MEMS switches: stiction of the bridge of the devices under test due to charging, and breakdown of the dielectric. We also show that the system can be used to monitor other characteristics, such as the rise- and fall-times and incomplete pull-in of the bridge of the switch when actuated.

  18. Beam patterns in an optical parametric oscillator set-up employing walk-off compensating beta barium borate crystals

    NASA Astrophysics Data System (ADS)

    Kaucikas, M.; Warren, M.; Michailovas, A.; Antanavicius, R.; van Thor, J. J.

    2013-02-01

    This paper describes the investigation of an optical parametric oscillator (OPO) set-up based on two beta barium borate (BBO) crystals, where the interplay between the crystal orientations, cut angles and air dispersion substantially influenced the OPO performance, and especially the angular spectrum of the output beam. Theory suggests that if two BBO crystals are used in this type of design, they should be of different cuts. This paper aims to provide an experimental manifestation of this fact. Furthermore, it has been shown that air dispersion produces similar effects and should be taken into account. An x-ray crystallographic indexing of the crystals was performed as an independent test of the above conclusions.

  19. Report on the test set-up for the structural testing of the Airmass Sunburst Ultralight Aircraft

    NASA Technical Reports Server (NTRS)

    Zimmerman, William; Smith, Howard W.

    1993-01-01

    This report reviews the test set-up and procedure for the structural testing of the Airmass Sunburst Ultralight Aircraft. In general aviation today, there is a growing need for more stringent design criteria for ultralight aircraft. Unlike most general aviation aircraft, the ultralight lacks sufficient design criteria and more importantly it lacks sufficient certification enforcement. The Airmass Sunburst ultralight that is currently being tested is responsible for over a dozen deaths. It is believed that had there been a more stringent criteria and certification process, this might have been prevented. Our attempt is to show that the failing loads of the aircraft in question are so far below that of the current design criteria, that the laws need to be changed.

  20. Measurement of nitrogen in the body using a commercial PGNAA system--phantom experiments.

    PubMed

    Chichester, D L; Empey, E

    2004-01-01

    An industrial prompt-gamma neutron activation analysis (PGNAA) system, originally designed for the real-time elemental analyses of bulk coal on a conveyor belt, has been studied to examine the feasibility of using such a system for body composition analysis. Experiments were conducted to measure nitrogen in a simple, tissue equivalent phantom comprised of 2.7 wt% of nitrogen. The neutron source for these experiments was 365 MBq (18.38 microg) of 252Cf located within an engineered low Z moderator and it yielded a dose rate in the measurement position of 3.91 mSv/h; data were collected using a 2780 cm(3) NaI(Tl) cylindrical detector with a digital signal processor and a 512 channel MCA. Source, moderator and detector geometries were unaltered from the system's standard configuration, where they have been optimized for considerations such as neutron thermalization, measurement sensitivity and uniformity, background radiation and external dose minimization. Based on net counts in the 10.8 MeV PGNAA nitrogen photopeak and its escape peaks the dose dependent nitrogen count rate was 11,600 counts/mSv with an uncertainty of 3.0% after 0.32 mSv (4.9 min), 2.0% after 0.74 mSv (11.4 min) and 1.0% after 3.02 mSv (46.4 min). PMID:14687637

  1. Elemental analysis of concrete samples using an accelerator-based PGNAA setup

    NASA Astrophysics Data System (ADS)

    Naqvi, A. A.; Nagadi, M. M.; Baghabra Al-Amoudi, Omar S.

    2004-09-01

    Elemental analysis of concrete samples was carried out using an accelerator-based prompt gamma ray neutron activation analysis (PGNAA) setup. The gamma rays were produced via the capture of thermal neutron in the concrete sample. The prompt gamma ray yield was measured for 12 cm long concrete samples as a function of sample radius over a range of 6-11.5 cm radii. The optimum yield of the prompt gamma rays from the concrete sample was measured from a sample with 11.5 cm radius. The gamma ray yield was also calculated for 12 cm long concrete samples with 6-11.5 cm radius using Monte Carlo simulations. The experimental results were in excellent agreement with the calculated yield of the prompt gamma rays from the samples. Result of this study has shown the useful application of an accelerator-based PGNAA setup in elemental analysis of concrete sample. The facility can be further used to determine the chloride and sulfate concentrations in concrete samples for corrosion studies of reinforcement steel in concrete structures.

  2. High temperature measurement set-up for the electro-mechanical characterization of robust thin film systems

    NASA Astrophysics Data System (ADS)

    Fricke, S.; Friedberger, A.; Seidel, H.; Schmid, U.

    2014-01-01

    Due to economic and environmental requirements there is a strong need both to increase the efficiency and to monitor the actual status of gas turbines, rocket engines and deep drilling systems. For these applications, micromachined pressure sensors based on a robust substrate material (e.g. sapphire) as well as strain gauges made of platinum for long-term stable operation are regarded as most promising to withstand harsh environments such as high temperature levels, aggressive media and/or high pressure loads. For pre-evaluation purposes, a novel, custom-built measurement set-up is presented allowing the determination of electro-mechanical thin film properties up to 850 °C. Key components of the measurement set-up are the one-sided clamped beam made of Al2O3 ceramics which is deflected by a quartz rod and a high precision encoder-controlled dc motor to drive the quartz rod. The specific arrangement of the infrared halogen heaters in combination with the gold coated quartz half shells ensures a high degree of temperature homogeneity along the beam axis. When exposed to tensile as well as compressive load conditions, the corresponding gauge factor values of 1 µm thick platinum thin films show a good comparison at room temperature and in the temperature range from 600 up to 850 °C where the effects originating from grain boundaries or from the film surfaces are negligible. Between 150 and 600 °C, however, a strong deviation in the gauge factor determination depending on the mechanical load condition is observed, which is attributed to the gliding of adjacent grains.

  3. Internal movement, set-up accuracy and margins for stereotactic body radiotherapy using a stereotactic body frame.

    PubMed

    Hansen, Anders T; Petersen, Jørgen B; Høyer, Morten

    2006-01-01

    The aim of this study was to evaluate the uncertainty of patient immobilization within the Elekta body frame (SBF) used for stereotactic body radiotherapy (SBRT) and to suggest margins sufficient to ensure dose coverage to the gross target volume (GTV). The study was based on the evaluation of repeated CT-scans of 30 patients treated by SBRT. The overall uncertainty was divided between uncertainty related to internal movement of the tumor and uncertainty in the patient set-up. Standard deviations of the overall tumor displacement were 2 mm, 3 mm and 4 mm in medial-lateral (m-l), anterior-posterior (a-p), and cranio-caudal (c-c) directions, respectively. In a model based on the data, an ellipsoid planned target volume (PTV) corresponding to the standard deviations in the orthogonal directions and a scaling factor, K defined a 3-dimentional (3-D) probability density. According to the model, a 90% probability of full dose coverage of the GTV was secured using margins of 9 mm (m-l), 9 mm (a-p) and 13 mm (c-c), respectively. The overall uncertainty was dominated by internal tumor movements whereas the set-up uncertainty of the patient in the SBF was less pronounced. It was concluded that the Elekta SBF is useful for immobilisation of patients for SBRT. However, due to internal movement conventional margins of 5 mm in m-l and a-p and 10 mm in the c-c directions may be insufficient for full dose coverage. PMID:16982562

  4. Detection of actinides and rare earths in natural matrices with the AGLAE new, high sensitivity detection set-up

    NASA Astrophysics Data System (ADS)

    Zucchiatti, Alessandro; Alonso, Ursula; Lemasson, Quentin; Missana, Tiziana; Moignard, Brice; Pacheco, Claire; Pichon, Laurent; Camarena de la Mora, Sandra

    2014-08-01

    A series of granite samples (Grimsel and Äspö) enriched by sorption with natU (10-3 M, 10-4 M, 10-5 M in solution) and La (10-3 M, 10-4 M in solution) has been scanned by PIXE over a surface of 1920 × 1920 mm2 together with non-enriched Grimsel and Äspö granites and a glass standard. An assessment of minimum detection limits, MDL's, for several elements has been performed with the use of standard materials. Due to mapping and the high sensitivity of the new AGLAE detection system, U levels around 30 ppm can be detected from the whole PIXE spectrum (one low energy detector and four summed filtered detectors) while U reach grains, inhomogeneously distributed over the surface can be clearly identified through the multi elemental maps and analyzed separately. Even the nominally enriched samples have La levels below the MDL, probably because precipitation of the element (and not adsorption) mostly took place, and precipitates were eliminated after surface cleaning carried out before PIXE analyses. A multi detector system that implies a PIXE detection solid angle much wider than in any other similar set-up (a factor of 2-5); a higher events selectivity, given by the possibility of filtering individually up to 4 PIXE detectors; a double RBS detector, the new Ion Beam Induced Luminescence (IBIL) spectrometry and gamma spectrometry. Full mapping capability in air, assisted by a powerful event by event reconstruction software. These features allow lower Minimum Detection Limits (MDL) which are highly beneficial to the analysis of cultural heritage objects, meaning generally a reduction of irradiation time. Paintings will then be studied without any damage to the pigments that have color change tendencies which is a major drawback of the previous system. Alternatively they could allow an increase in information collected at equal time, particularly considering the detector's fast response and therefore the potential for high beam currents when sample damage can be

  5. Application of flat panel digital imaging for improvement of ocular melanoma patient set-up in proton beam therapy

    NASA Astrophysics Data System (ADS)

    Daftari, Inder K.; Essert, Timothy; Phillips, Theodore L.

    2009-01-01

    In order to reduce the dose to surrounding critical tissues and also minimize the probability of recurrence of the tumor the placement of radiation fields relative to patient anatomy is very essential in proton beam therapy of ocular tumors. To achieve this objective, patient setup and field placement have been verified before treatment by analyzing the portal images obtained with Polaroid film-camera system. The Polaroid films are becoming expensive and obsolete, making new methods of verifying the patient treatment position essential. The objective of this study was to implement an orthogonal flat panel digital imaging (FPDI) system as a tool to image-guided radiation therapy (IGRT) on the UC Davis cyclotron proton beam therapy line and to use the system for patient setup verification. The image quality of the system is sufficient to see an air hole with a diameter of 0.5 mm at a depth of 9 mm, in a 10 cm Lucite phantom. The subject contrast of the FPDI system varied from 16% to 29% by varying the size of the air hole in the phantom from 1 to 5 mm and changing the depth from 9 to 15 mm. The subject contrast for 0.5 mm air hole was 11%. The comparison of the setup variations as measured from Polaroid port films and FPDI was 0.1±0.7 mm in the X-direction, 0.2±0.2 mm in the Y-direction and 0.04±0.1 mm in Z-direction, respectively. The day-to-day positional variations in-patient set-ups were studied for 30 patients using the FPDI system. The patient position set-up on first day of treatment [defined by the X, Y, Z coordinates of the chair and head holder] was registered as the reference image. The comparison of day-to-day patient position with reference image indicated net translation along the three orthogonal axes as 0.3±1.88 mm in right-left direction, -0.3±1.78 in superior-inferior direction and -0.6±2.8 mm in anterior-posterior direction. The image quality of the FPDI system was sufficient to clearly reveal the radio-opaque markers on the digital image. In

  6. TWINNING between Institutions in developed and less developed countries: an ideal way to set-up an astrophysics program

    NASA Astrophysics Data System (ADS)

    Carignan, Claude

    2015-03-01

    It is very difficult to start from scratch a new Astrophysics program in a country with very little or no researchers in the field. In 2007, we began to set-up an Astrophysics program by TWINNING the Université de Ouagadougou with the Université de Montréal in Canada, the Université de Provence in France and the University of Cape Town in South Africa. Already, courses are given at the undergraduate and Master levels and a teaching Observatory has been built. A 1m research telescope was also moved from the La Silla Observatory in Chile to Burkina Faso and the infrastructure is being built at the moment on mount Djaogari in the north-eastern part of the country. In the meantime, 6 students are doing their PhD in Astrophysics overseas (Canada, France and South Africa) and will become the core of the research group at the Université de Ouagadougou. An engineer is also doing his PhD in Astronomical Instrumentation to help with the maintenance of the equipment on the Research Telescope.

  7. The capillary channel flow experiments on the International Space Station: experiment set-up and first results

    NASA Astrophysics Data System (ADS)

    Canfield, P. J.; Bronowicki, P. M.; Chen, Y.; Kiewidt, L.; Grah, A.; Klatte, J.; Jenson, R.; Blackmore, W.; Weislogel, M. M.; Dreyer, M. E.

    2013-05-01

    This paper describes the experiments on flow rate limitation in open capillary channel flow that were performed on board the International Space Station in 2011. Free surfaces (gas-liquid interfaces) of open capillary channels balance the pressure difference between the flow of the liquid in the channel and the ambient gas by changing their curvature in accordance with the Young-Laplace equation. A critical flow rate of the liquid in the channel is exceeded when the curvature of the free surface is no longer able to balance the pressure difference and, consequently, the free surface collapses and gas is ingested into the liquid. This phenomenon was observed using the set-up described herein and critical flow rates are presented for steady flow over a range of channel lengths in three different cross-sectional geometries (parallel plates, groove, and wedge). All channel shapes displayed decreasing critical flow rates for increasing channel lengths. Bubble ingestion frequencies and bubble volumes are presented for gas ingestion at supercritical flow rates in the groove channel and in the wedge channel. At flow rates above the critical flow rate, bubble ingestion frequency appears to depend on the flow rate in a linear fashion, while bubble volume remains more or less constant. The performed experiments yield vast data sets on flow rate limitation in capillary channel flow in microgravity and can be utilised to validate numerical and analytical methods.

  8. Linking mathematics with engineering applications at an early stage - implementation, experimental set-up and evaluation of a pilot project

    NASA Astrophysics Data System (ADS)

    Rooch, Aeneas; Junker, Philipp; Härterich, Jörg; Hackl, Klaus

    2016-03-01

    Too difficult, too abstract, too theoretical - many first-year engineering students complain about their mathematics courses. The project MathePraxis aims to resolve this disaffection. It links mathematical methods as they are taught in the first semesters with practical problems from engineering applications - and thereby shall give first-year engineering students a vivid and convincing impression of where they will need mathematics in their later working life. But since real applications usually require more than basic mathematics and first-year engineering students typically are not experienced with construction, mensuration and the use of engineering software, such an approach is hard to realise. In this article, we show that it is possible. We report on the implementation of MathePraxis at Ruhr-Universität Bochum. We describe the set-up and the implementation of a course on designing a mass damper which combines basic mathematical techniques with an impressive experiment. In an accompanying evaluation, we have examined the students' motivation relating to mathematics. This opens up new perspectives how to address the need for a more practically oriented mathematical education in engineering sciences.

  9. Evaluation of a cryopreservation procedure to set up a new bone marrow transplant unit using lymphocyte proliferation test.

    PubMed

    Wong, Peerapon; Pongcharoen, Sutatip; Pangwangthong, Kullanit; Supalap, Kwansuda; Tapprom, Akamon; Deoisares, Rawisut

    2012-01-01

    A bone marrow transplant (BMT) is one kind of standard treatment modality in advanced hemato-oncology. In order to set up a BMT unit, one of the important steps before starting a clinical program is to evaluate the cryopreservation procedure for stem cell storage. Twenty one bags of buffy coat were used to be the testing specimens. They were processed and frozen according to cryopreservation protocol and kept in liquid nitrogen for 2 weeks. The evaluation process was carried out with a lymphocyte proliferation test together with trypan blue staining. By measuring the optical density of each lymphocyte containing well after stimulation, the lymphocyte proliferation value (LPV) could be obtained. When comparing them before and after cryopreservation, the LPV was 2.064 ± 0.379 (mean ± SD) and 1.913 ± 0.546, (p = 0.314), respectively. At 2 weeks after cryopreservation, comparing between the frozen group and the unfrozen control, the LPV was 1.913 ± 0.546 and 0.486 ± 0.453, (p < 0.05), respectively. The LPV showed clear efficacy of the procedure, especially for preserving the cellular proliferation function. Our model of the cryopreservation procedure evaluation at pre-clinical phase by use of a buffy coat and lymphocyte proliferation test seems feasible for newly-established small BMT units. With these results, clinical transplantations can be performed with more confidence. PMID:21649473

  10. An experimental set-up to analyse the oxygen consumption of elastomers during ageing by using a differential oxygen analyser

    NASA Astrophysics Data System (ADS)

    Herzig, Alexander; Johlitz, Michael; Lion, Alexander

    2015-11-01

    Ageing of polymers becomes more and more important. This can be seen by the increasing number of research projects dealing with this topic. However, the influence of oxygen on changes in the mechanical performance is undisputable and important with respect to the lifetime of polymer products. Therefore, a respirometer offers the potential to detect the smallest amounts of oxygen changes in the polymers' ambient air. It will be used to analyse the oxygen consumption of rubber which is exposed for different times to elevated temperatures. In this contribution, virgin rubber samples are aged for various times in a sealed chamber at temperatures of 60, 80 and 100°C. The decline of the oxygen concentration in the ambient air is measured by flushing the chamber with dried and cleaned air which is conducted into the respirometer. The oxygen concentration is compared with that in a reference chamber, which is exposed to the same ageing conditions as the sample under investigation. The absorbed oxygen is relevant for ageing and a considerable factor for further investigations. For this reason, an experimental set-up using a differential oxygen analyser is developed, which allows for ageing several samples simultaneously in external climate chambers. The comparison of the change in the mechanical material behaviour after ageing can provide an important contribution for improving constitutive models or ongoing researches on the fatigue strength of polymers. This work shows the development of an improved method for combining mechanical testing and the measurement of oxygen consumption.

  11. The European VLF/LF radio network to search for earthquake precursors: setting up and natural/man-made disturbances

    NASA Astrophysics Data System (ADS)

    Biagi, P. F.; Maggipinto, T.; Righetti, F.; Loiacono, D.; Schiavulli, L.; Ligonzo, T.; Ermini, A.; Moldovan, I. A.; Moldovan, A. S.; Buyuksarac, A.; Silva, H. G.; Bezzeghoud, M.; Contadakis, M. E.

    2011-02-01

    In the last years disturbances in VLF/LF radio signals related to seismic activity have been presented. The radio data were collected by receivers located on the ground or on satellites. The ground-based research implies systematic data collection by a network of receivers. Since 2000 the "Pacific VLF network", conducted by Japanese researchers, has been in operation. During 2008 a radio receiver was developed by the Italian factory Elettronika (Palo del Colle, Bari). The receiver is equipment working in VLF and LF bands. It can monitor 10 frequencies distributed in these bands and, for each of them, it saves the power level. At the beginning of 2009, five receivers were made for the realization of the "European VLF/LF Network"; two were planned for Italy and one for Greece, Turkey and Romania, respectively. In 2010 the network was enlarged to include a new receiver installed in Portugal. In this work, first the receiver and its setting up in the different places are described. Then, several disturbances in the radio signals related to the transmitters, receivers, meteorological/geomagnetic conditions are presented and described.

  12. Set up of a cardiovascular simulator: application to the evaluation of the dynamical behavior of atheroma plaques in human arteries

    NASA Astrophysics Data System (ADS)

    Brum, J.; Bia, D.; Benech, N.; Balay, G.; Armentano, R.; Negreira, C.

    2010-01-01

    In this work a circulating loop capable of mimicking the physiological pressure and flow conditions inside a vessel is set up. The circulating loop consists of an artificial heart coupled to a perfusion line made of polyethylene and silicon. The artificial heart is driven by a pneumatic pump which provides the desired heart rate, pressure values and length of the systolic and diastolic period of each cycle. To measure the changes in diameter of the segment under study, an ultrasonic probe in pulse eco mode is used. For pressure monitoring a pressure sensor is positioned inside the sample. Pressure-diameter loops were obtained for characterization of the dynamical properties of the arterial wall. In vitro measurements were made on three different conduits: 1) Calibrated tubes made of latex: these phantoms were characterized by the presented method, 2) Non-atherosclerotic human carotid arteries obtained from donors and 3) Atherosclerotic human carotid arteries with atheroma plaques. In the three cases, under physiological simulated conditions, the mechanical properties of the conduit were obtained. We conclude that atheroma plaques were successfully detected and its dynamical properties characterized. This method could be used in the experimental and clinical field to characterize the effects of atheroma plaques on the arterial wall biomechanics.

  13. Novel Set-Up for Low-Disturbance Sampling of Volatile and Non-volatile Compounds from Plant Roots.

    PubMed

    Eilers, Elisabeth J; Pauls, Gerhard; Rillig, Matthias C; Hansson, Bill S; Hilker, Monika; Reinecke, Andreas

    2015-03-01

    Most studies on rhizosphere chemicals are carried out in substrate-free set-ups or in artificial substrates using sampling methods that require an air flow and may thus cause disturbance to the rhizosphere. Our study aimed to develop a simplified and inexpensive system that allows analysis of rhizosphere chemicals at experimentally less disturbed conditions. We designed a mesocosm in which volatile rhizosphere chemicals were sampled passively (by diffusion) without air- and water flow on polydimethylsiloxane-(PDMS) tubes. Dandelion (Taraxacum sect. ruderalia) was used as model plant; roots were left undamaged. Fifteen volatiles were retrieved from the sorptive material by thermal desorption for analysis by gas chromatography/mass spectrometry (GC/MS). Furthermore, three sugars were collected from the rhizosphere substrate by aqueous extraction and derivatized prior to GC/MS analysis. In order to study how the quantity of detected rhizosphere compounds depends on the type of soil or substrate, we determined the matrix-dependent recovery of synthetic rhizosphere chemicals. Furthermore, we compared sorption of volatiles on PDMS tubes with and without direct contact to the substrate. The results show that the newly designed mesocosm is suitable for low-invasive extraction of volatile and non-volatile compounds from rhizospheres. We further highlight how strongly the type of substrate and contact of PDMS tubes to the substrate affect the detectability of compounds from rhizospheres. PMID:25795090

  14. The set-up of a high temperature superconductor radio-frequency SQUID microscope for magnetic nanoparticle detection

    NASA Astrophysics Data System (ADS)

    Schmidt, M.; Krause, H.-J.; Banzet, M.; Lomparski, D.; Schubert, J.; Zander, W.; Zhang, Y.; Akram, R.; Fardmanesh, M.

    2006-05-01

    SQUID (superconducting quantum interference device) microscopes are versatile instruments for biosensing applications, in particular for magnetic nanoparticle detection in immunoassay experiments. We are developing a SQUID microscope based on an HTS rf SQUID magnetometer sensor with a substrate resonator. For the cryogenic set-up, a configuration was realized in which the cryostat is continuously refilled and kept at a constant liquid nitrogen level by an isolated tube connection to a large liquid nitrogen reservoir. The SQUID is mounted on top of a sapphire finger, connected to the inner vessel of the stainless steel cryostat. The vacuum gap between the cold SQUID and room temperature sample is adjusted by the precise approach of a 50 µm thin sapphire window using a single fine thread wheel. We investigated possible sensing tip configurations and different sensor integration techniques in order to achieve an optimized design. A new scheme of coupling the rf SQUID from its back to a SrTiO3 substrate resonator was adopted for the purpose of minimization of the sensor-to-sample spacing. By SQUID substrate thinning and washer size reduction, the optimum coupling conditions for back coupling were determined for different rf SQUID magnetometers prepared on LaAlO3 and SrTiO3 substrates. The SQUID microscope system is characterized with respect to its spatial resolution and its magnetic field noise. The SQUID microscope instrument will be used for magnetic nanoparticle marker detection.

  15. An experimental set-up to study carbon, water, and nitrate uptake rates by hydroponically grown plants.

    PubMed

    Andriolo, J L; Le Bot, J; Gary, C; Sappe, G; Orlando, P; Brunel, B; Sarrouy, C

    1996-01-01

    The experimental system described allows concomitant hourly measurements of CO2, H2O, and NO3 uptake rates by plants grown hydroponically in a greenhouse. Plants are enclosed in an airtight chamber through which air flows at a controlled speed. Carbon dioxide exchange and transpiration rates are determined from respective differences of concentrations of CO2 and water vapor of the air at the system inlet and outlet. This set-up is based on the "open-system" principle with improvements made on existing systems. For instance, propeller anemometers are used to monitor air flow rates in the chamber. From their signal it is possible to continuously adjust air speed to changing environmental conditions and plant activity. The air temperature inside the system therefore never rises above that outside. Water and NO3 uptake rates are calculated at time intervals from changes in the volume and the NO3 concentration of the nutrient solution in contact with the roots. The precise measurement of the volume of solution is achieved using a balance which has a higher precision than any liquid level sensors. Nitrate concentration is determined in the laboratory from aliquots of solution sampled at time intervals. A number of test runs are reported which validate the measurements and confirm undisturbed conditions within the system. Results of typical diurnal changes in CO2, H2O, and NO3 uptake rates by fruiting tomato plants are also presented. PMID:11541097

  16. Set-up of debris-flow monitoring stations in the Eastern Pyrenees. Preliminary results and first experiences.

    NASA Astrophysics Data System (ADS)

    Hürlimann, Marcel; Abancó, Claudia; Moya, Jose; Chevalier, Guillaume; Raïmat, Carles; Luis-Fonseca, Roberto

    2010-05-01

    Direct observations of debris flows in the field by monitoring stations are of great importance to improve understandings of triggering, flow behaviour and accumulation of debris flows. Upon the knowledge of the authors, in Europe debris-flow monitoring stations are only situated in the Alps (Italy and Switzerland), while no test site is located in a catchment affected by Mediterranean climate. In 2005, the first monitoring system was set up by GEOBRUGG IBERICA SA in the Erill catchment, situated in the Axial Pyrenees. A flexible ring net VX160-H4 with load-cells was installed together with a video camera and four geophones. In addition, a meteorological station completed the instrumentation. During 2009, the monitoring of two additional catchments has been set up; Senet in the Axial Pyrenees and Ensija in the Pre-Pyrenees. Four geophones and one ultrasonic device are installed along the torrent in order to determine the flow velocity and flow depth/discharge of the events. As in Erill, a meteorological station completes the devices and measures rainfall and temperature. The main objective of the three monitoring stations is to get some insights on how the Mediterranean climate influences the critical rainfall for debris-flow initiation. The flow behaviour of debris flows is another major goal, while the Erill test site focuses basically on the effectiveness of flexible ring nets. In addition, the Erill installation also acts as protection for the village located on the fan. The calibration, installation and analysis during the testing phase showed that a correct implementation of the different sensors is not an easy task and needs knowledge in geophysics, electronics, telecommunications etc. Especially geophones and ultrasonic devices need special attentions. Geophone outputs are strongly affected by the type of underground and the distance to the torrent, while the measures of the ultrasonic sensor clearly depend on the temperature. To simplify the data storage

  17. The analog linear interpolation approach for Monte Carlo simulation of PGNAA: The CEARPGA code

    NASA Astrophysics Data System (ADS)

    Zhang, Wenchao; Gardner, Robin P.

    2004-01-01

    The analog linear interpolation approach (ALI) has been developed and implemented to eliminate the big weight problem in the Monte Carlo simulation code CEARPGA. The CEARPGA code was previously developed to generate elemental library spectra for using the Monte Carlo - library least-squares (MCLLS) approach in prompt gamma-ray neutron activation analysis (PGNAA). In addition, some other improvements to this code have been introduced, including (1) adopting the latest photon cross-section data, (2) using an improved detector response function, (3) adding the neutron activation backgrounds, (4) generating the individual natural background libraries, (5) adding the tracking of annihilation photons from pair production interactions outside of the detector and (6) adopting a general geometry package. The simulated result from the new CEARPGA code is compared with those calculated from the previous CEARPGA code and the MCNP code and experimental data. The new CEARPGA code is found to give the best result.

  18. Elemental PGNAA analysis using gamma-gamma coincidence counting with the library least-squares approach

    NASA Astrophysics Data System (ADS)

    Metwally, Walid A.; Gardner, Robin P.; Mayo, Charles W.

    2004-01-01

    An accurate method for determining elemental analysis using gamma-gamma coincidence counting is presented. To demonstrate the feasibility of this method for PGNAA, a system of three radioisotopes (Na-24, Co-60 and Cs-134) that emit coincident gamma rays was used. Two HPGe detectors were connected to a system that allowed both singles and coincidences to be collected simultaneously. A known mixture of the three radioisotopes was used and data was deliberately collected at relatively high counting rates to determine the effect of pulse pile-up distortion. The results obtained, with the library least-squares analysis, of both the normal and coincidence counting are presented and compared to the known amounts. The coincidence results are shown to give much better accuracy. It appears that in addition to the expected advantage of reduced background, the coincidence approach is considerably more resistant to pulse pile-up distortion.

  19. A new particle-induced X-ray emission set-up for laterally resolved analysis over wide areas

    NASA Astrophysics Data System (ADS)

    Hanf, D.; Buchriegler, J.; Renno, A. D.; Merchel, S.; Munnik, F.; Ziegenrücker, R.; Scharf, O.; Nowak, S. H.; von Borany, J.

    2016-06-01

    The recently installed and unique PIXE (particle-induced X-ray emission) set-up at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is mainly dedicated to applications for a detailed overview of elemental composition over large sample areas within a short time even at trace level. The so-called High-Speed-PIXE (HS-PIXE), a combination of a pnCCD-based pixel-detector with polycapillary X-ray optics, offers simultaneous imaging of sample areas up to 12 × 12 mm2 with a lateral resolution better than 100 μm. Each of the 264 × 264 individual pixels detects X-ray photons in an energy range from 2 keV to 20 keV with an energy resolution of 152 eV (@Mn-Kα). A high precision sample manipulator offers the inspection of areas up to 250 × 250 mm2. During first experiments the determined resolution is (76 ± 23) μm using a sample of well-known sharp-edged chromium patterns. Trace element analysis has been performed using a geological sample, a tin ore, with an average Ta-concentration below 0.1 at.%. Fine-zoned structures became visible in the Ta-Lα intensity map within only 45 min. The High-Speed-PIXE closes a gap in the analytical process flow chain especially for geoanalytical characterisations. It is a unique and fast detection system to identify areas of interest in comparably short time at large-area scale for further analysis.

  20. Magnetic resonance angiographic evaluation of circle of Willis: A morphologic study in a tertiary hospital set up

    PubMed Central

    Naveen, Shankar Rao; Bhat, Venkatraman; Karthik, Gadabanahalli Ashok

    2015-01-01

    Background: Anatomy of circle of Willis (CW) shows wide variation in different individuals, population groups, and has vital clinical significance in causation and presentation of clinical disease. This study evaluates the anatomical variations, incidence of various common anomalies of CW in south Indian tertiary hospital set up, using three-dimensional time-of-flight (3D-TOF) magnetic resonance angiography (MRA). Materials and Methods: A total of 300 patients referred for neuroimaging study over a period of 2-year were included in the analysis. In this prospective and retrospective study, 198 men and 102 women; mean age, 55 years) underwent 3D-TOF MR angiograms of the CW using a 1.5-tesla MR scanner. Images were reviewed for anatomical configuration of the CW using maximum intensity projection (MIP) and 3D volume rendered images. Results: On analysis, a complete CW was seen in 50 (16.6%) of 300 subjects. An incomplete anterior and posterior CW was found in 66 (22%) The remaining 184 (61.3%) subjects had partially complete CW configuration. The most common type of CW in a single subject was anterior variant type A and posterior type variant E. Conclusion: We observed wide variation in CW configuration in our patients. The prevalence of complete configuration of the circle is 16.6%; slightly higher in females and younger subjects. Complete anterior circle was present in 77.3%. Most common anterior variant is type A (normal anterior configuration) with a prevalence of 66%. The most common posterior circle variant is type E (hypoplasia or absence of both PcomA) with 32.6%. Overall, CW variants are slightly more common among the women in comparison to men. Incidence of associated anomalies like aneurysm or arteriovenous malformation (AVM) was comparable to that described in literature. PMID:26713008

  1. Contrast-Enhanced Proton Radiography for Patient Set-up by Using X-Ray CT Prior Knowledge

    SciTech Connect

    Spadea, Maria Francesca; Fassi, Aurora; Zaffino, Paolo; Riboldi, Marco; Baroni, Guido; Depauw, Nicolas; Seco, Joao

    2014-11-01

    Purpose: To obtain a contrasted image of the tumor region during the setup for proton therapy in lung patients, by using proton radiography and x-ray computed tomography (CT) prior knowledge. Methods and Materials: Six lung cancer patients' CT scans were preprocessed by masking out the gross tumor volume (GTV), and digitally reconstructed radiographs along the planned beam's eye view (BEV) were generated, for a total of 27 projections. Proton radiographies (PR) were also computed for the same BEV through Monte Carlo simulations. The digitally reconstructed radiograph was subtracted from the corresponding proton image, resulting in a contrast-enhanced proton radiography (CEPR). Michelson contrast analysis was performed both on PR and CEPR. The tumor region was then automatically segmented on CEPR and compared to the ground truth (GT) provided by physicians in terms of Dice coefficient, accuracy, precision, sensitivity, and specificity. Results: Contrast on CEPR was, on average, 4 times better than on PR. For 10 lateral projections (±45° off of 90° or 270°), although it was not possible to distinguish the tumor region in the PR, CEPR offers excellent GTV visibility. The median ± quartile values of Dice, precision, and accuracy indexes were 0.86 ± 0.03, 0.86 ± 0.06, and 0.88 ± 0.02, respectively, thus confirming the reliability of the method in highlighting tumor boundaries. Sensitivity and specificity analysis demonstrated that there is no systematic over- or underestimation of the tumor region. Identification of the tumor boundaries using CEPR resulted in a more accurate and precise definition of GTV compared to that obtained from pretreatment CT. Conclusions: In most proton centers, the current clinical protocol is to align the patient using kV imaging with bony anatomy as a reference. We demonstrated that CEPR can significantly improve tumor visualization, allowing better patient set-up and permitting image guided proton therapy (IGPT)

  2. Organizational development trajectory of a large academic radiotherapy department set up similarly to a prospective clinical trial: the MAASTRO experience

    PubMed Central

    Boersma, L; Dekker, A; Hermanns, E; Houben, R; Govers, M; van Merode, F; Lambin, P

    2015-01-01

    Objective: To simultaneously improve patient care processes and clinical research activities by starting a hypothesis-driven reorganization trajectory mimicking the rigorous methodology of a prospective clinical trial. Methods: The design of this reorganization trajectory was based on the model of a prospective trial. It consisted of (1) listing problems and analysing their potential causes, (2) defining interventions, (3) defining end points and (4) measuring the effect of the interventions (i.e. at baseline and after 1 and 2 years). The primary end point for patient care was the number of organizational root causes of incidents/near incidents; for clinical research, it was the number of patients in trials. There were several secondary end points. We analysed the data using two sample z-tests, χ2 test, a Mann–Whitney U test and the one-way analysis of variance with Bonferroni correction. Results: The number of organizational root causes was reduced by 27% (p < 0.001). There was no effect on the percentage of patients included in trials. Conclusion: The reorganizational trajectory was successful for the primary end point of patient care and had no effect on clinical research. Some confounding events hampered our ability to draw strong conclusions. Nevertheless, the transparency of this approach can give medical professionals more confidence in moving forward with other organizational changes in the same way. Advances in knowledge: This article is novel because managerial interventions were set up similarly to a prospective clinical trial. This study is the first of its kind in radiotherapy, and this approach can contribute to discussions about the effectiveness of managerial interventions. PMID:25679320

  3. Decompression induced bubble dynamics on ex vivo fat and muscle tissue surfaces with a new experimental set up.

    PubMed

    Papadopoulou, Virginie; Evgenidis, Sotiris; Eckersley, Robert J; Mesimeris, Thodoris; Balestra, Costantino; Kostoglou, Margaritis; Tang, Meng-Xing; Karapantsios, Thodoris D

    2015-05-01

    Vascular gas bubbles are routinely observed after scuba dives using ultrasound imaging, however the precise formation mechanism and site of these bubbles are still debated and growth from decompression in vivo has not been extensively studied, due in part to imaging difficulties. An experimental set-up was developed for optical recording of bubble growth and density on tissue surface area during hyperbaric decompression. Muscle and fat tissues (rabbits, ex vivo) were covered with nitrogen saturated distilled water and decompression experiments performed, from 3 to 0bar, at a rate of 1bar/min. Pictures were automatically acquired every 5s from the start of the decompression for 1h with a resolution of 1.75μm. A custom MatLab analysis code implementing a circular Hough transform was written and shown to be able to track bubble growth sequences including bubble center, radius, contact line and contact angles over time. Bubble density, nucleation threshold and detachment size, as well as coalescence behavior, were shown significantly different for muscle and fat tissues surfaces, whereas growth rates after a critical size were governed by diffusion as expected. Heterogeneous nucleation was observed from preferential sites on the tissue substrate, where the bubbles grow, detach and new bubbles form in turn. No new nucleation sites were observed after the first 10min post decompression start so bubble density did not vary after this point in the experiment. In addition, a competition for dissolved gas between adjacent multiple bubbles was demonstrated in increased delay times as well as slower growth rates for non-isolated bubbles. PMID:25835147

  4. A Monte Carlo simulation and setup optimization of output efficiency to PGNAA thermal neutron using 252Cf neutrons

    NASA Astrophysics Data System (ADS)

    Zhang, Jin-Zhao; Tuo, Xian-Guo

    2014-07-01

    We present the design and optimization of a prompt γ-ray neutron activation analysis (PGNAA) thermal neutron output setup based on Monte Carlo simulations using MCNP5 computer code. In these simulations, the moderator materials, reflective materials, and structure of the PGNAA 252Cf neutrons of thermal neutron output setup are optimized. The simulation results reveal that the thin layer paraffin and the thick layer of heavy water moderating effect work best for the 252Cf neutron spectrum. Our new design shows a significantly improved performance of the thermal neutron flux and flux rate, that are increased by 3.02 times and 3.27 times, respectively, compared with the conventional neutron source design.

  5. Experimental verification of modeling results for a PGNAA system for nondestructive assay of RCRA metals in drums

    PubMed

    Dulloo; Ruddy; Congedo; Seidel; McIlwain

    2000-10-01

    The use of pulsed gamma neutron activation analysis (PGNAA) for the nondestructive assay of mercury, cadmium and lead in a concrete matrix has been demonstrated. Calculations have also been performed to study interference with PGNAA detection sensitivity resulting from the presence of 238U, 235U, and 239Pu at levels expected in mixed waste. Analyses based on transport calculations examined the effects of these nuclides on neutron kinetics, and the contribution from the capture, fission and decay gamma-rays emitted by the nuclides to the gamma-ray spectrum. These calculations predicted insignificant effects on the system's detection limits (115, 9 and 4400 ppm for Hg, Cd and Pb, respectively, for a 2000 s assay). This paper describes verification measurements recently conducted using samples of 235U and 231U in the test drum geometry, which have provided experimental confirmation of the modeling results. PMID:11003484

  6. Composition analysis of large samples with PGNAA using a fixed point iteration

    NASA Astrophysics Data System (ADS)

    Akkurt, Hatice

    2002-09-01

    The composition problem in large sample prompt gamma neutron activation analysis (PGNAA) is a nonlinear inverse problem. The basic form of the nonlinear inverse composition problem is presented. This problem is then formulated in a general way, as a fixed point problem, without addressing any specific application or sample type or linearization approach. This approach of formulating the problem as a fixed point problem suggested a natural fixed point iteration. The algorithm of the fixed point iteration solves the nonlinear composition problem using a combination of measured and computed data. The effectiveness of the fixed point iteration for composition analysis is demonstrated using purely numerical experiments. These numerical experiments showed that the fixed point iteration can be successfully applied to find the bulk composition of large samples, with excellent agreement between the estimated and true composition of the samples, in a few iterations, independent of the initial guess. In order to test the fixed point iteration using real experimental data, a series of large sample PGNAA measurements were performed at ANL-W. These experiments are described and the measured spectra for the samples are presented. Then, the fixed point iteration is applied for these real experiments to find the composition of the samples. In all of the cases, except borated polyethylene, the composition of the large samples are found in a few iterations with errors less than +/-1.3%. The effectiveness of the fixed point iteration is thus demonstrated with many proof-of-principle measurements. While testing the fixed point iteration algorithm, published values of the source spectrum and relative detector efficiencies are used. The sensitivity of the fixed point iteration to source spectrum is investigated and it is shown that the estimated composition results are not very sensitive to the change in the source spectrum. The reason behind the slow convergence for the borated

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

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

    SciTech Connect

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

    2013-04-19

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

  9. Sub-unit vaccine against S. aureus-mediated infections: set-up of nano-sized polymeric adjuvant.

    PubMed

    Colonna, C; Dorati, R; Conti, B; Caliceti, P; Genta, I

    2013-08-16

    The aim of this work was the design of a novel adjuvanted system for vaccination against S. aureus-mediated infections: in particular, poly-lactide-co-glycolide (PLGA) nanoparticles were developed in order to efficiently load and boost a sub-unit model vaccine, namely a purified recombinant collagen binding bacterial adhesin fragment (CNA19). At first, the assessment of the actual immunogenicity of free CNA19 via subcutaneous administration was evaluated, in order to consider it as subunit antigen model. Secondly, for the development of CNA19 loaded PLGA nanoparticles, a preliminary study was focused on the production of well-formed nanoparticles by w/o/w double emulsion method exploiting ultrasonication cycles under mild conditions, then the optimization of the freeze-drying conditions and different CNA19 loading methods were considered (encapsulation, adsorption of on blank or CNA19 encapsulated nanoparticles). The set-up preparation method (process yield of about 83%) permitted to obtain CNA19 loaded nanoparticles with spherical shape, narrow size distribution (187.41 ± 51.2 nm), a slightly negative zeta-potential (-2.91 ± 0.64 mV) and to elicit satisfactory protein encapsulation efficiency (75.91 ± 4.22%) and loading capacity (8.59 ± 0.33 μg CNA19/nanoparticles mg). Then, CNA19 loaded PLGA nanoparticles were characterized by (i) an in vitro release test performed at different temperatures, namely 4°C, 25°C and 37°C, testing the antigen integrity (SDS-PAGE) and activity (ELISA); (ii) an in vitro stability study in terms of dimension and surface charge performed in a 21 days period of time. At 37°C there was evidence of a sustained release of the antigen, in active form, for almost 240 h with a burst release of about 20% in the first 2h. At 4°C stability tests and activity assays allowed to identify storage conditions useful to maintain CNA19 activity and easily NP re-suspendability with intact physical characteristics. Furthermore the evaluation of CNA

  10. The Interaction Between Dynamics and Chemistry of Ozone in the Set-up Phase of the Northern Hemisphere Polar Vortex

    NASA Technical Reports Server (NTRS)

    Kawa, S. R.; Bevilacqua, R.; Margitan, J. J.; Douglass, A. R.; Schoeberl, M. R.; Hoppel, K.; Sen, B.; Bhartia, P. K. (Technical Monitor)

    2001-01-01

    The morphology and evolution of the stratospheric ozone (O3) distribution at high latitudes in the Northern Hemisphere (NH) are examined for the late summer and fall seasons of 1999. This time period sets the O3 initial condition for the SOLVE/THESEO field mission performed during winter 1999-2000. In situ and satellite data are used along with a three-dimensional model of chemistry and transport (CTM) to determine the key processes that control the distribution of O3 in the lower-to-middle stratosphere. O3 in the vortex at the beginning of the winter season is found to be nearly constant from 500 to above 800 K with a value at 3 ppmv +/- approx. 10%. Values outside the vortex are up to a factor of 2 higher and increase significantly with potential temperature. The seasonal time series of data from POAM shows that relatively low O3 mixing ratios, which characterize the vortex in late fall, are already present at high latitudes at the end of summer before the vortex circulation sets up. Analysis of the CTM output shows that the minimum O3 and increase in variance in late summer are the result of: 1) stirring of polar concentric O3 gradients by nascent wave-driven transport, and 2) an acceleration of net photochemical loss with decreasing solar illumination. The segregation of low O3 mixing ratios into the vortex as the circulation strengthens through the fall suggests a possible feedback role between O3 chemistry and the vortex formation dynamics. Trajectory calculations from O3 sample points early in the fall, however, show only a weak correlation between initial O3 mixing ratio and potential vorticity later in the season consistent with order-of-magnitude calculations for the relative importance of O3 in the fall radiative balance at high latitudes. The possible connection between O3 chemistry and the dynamics of vortex formation does suggest that these feedbacks and sensitivities need to be better understood in order to make confident predictions of the recovery

  11. Set-up and calibration of an indoor nozzle-type rainfall simulator for soil erosion studies

    NASA Astrophysics Data System (ADS)

    Lassu, T.; Seeger, M.

    2012-04-01

    Rainfall simulation is one of the most prevalent methods used in soil erosion studies on agricultural land. In-situ simulators have been used to relate soil surface characteristics and management to runoff generation, infiltration and erosion, eg. the influence of different cultivation systems, and to parameterise erosion models. Laboratory rainfall simulators have been used to determine the impact of the soil surface characteristics such as micro-topography, surface roughness, and soil chemistry on infiltration and erosion rates, and to elucidate the processes involved. The purpose of the following study is to demonstrate the set-up and the calibration of a large indoor, nozzle-type rainfall simulator (RS) for soil erosion, surface runoff and rill development studies. This RS is part of the Kraijenhoff van de Leur Laboratory for Water and Sediment Dynamics in Wageningen University. The rainfall simulator consists from a 6 m long and 2,5 m wide plot, with metal lateral frame and one open side. Infiltration can be collected in different segments. The plot can be inclined up to 15.5° slope. From 3,85 m height above the plot 2 Lechler nozzles 460.788 are sprinkling the water onto the surface with constant intensity. A Zehnder HMP 450 pump provides the constant water supply. An automatic pressure switch on the pump keeps the pressure constant during the experiments. The flow rate is controlled for each nozzle by independent valves. Additionally, solenoid valves are mounted at each nozzle to interrupt water flow. The flow is monitored for each nozzle with flow meters and can be recorded within the computer network. For calibration of the RS we measured the rainfall distribution with 60 gauges equally distributed over the plot during 15 minutes for each nozzle independently and for a combination of 2 identical nozzles. The rainfall energy was recorded on the same grid by measuring drop size distribution and fall velocity with a laser disdrometer. We applied 2 different

  12. Accurate measurements of fission-fragment yields in 234,235,236,238U(γ,f) with the SOFIA set-up

    NASA Astrophysics Data System (ADS)

    Chatillon, A.; Taïeb, J.; Martin, J.-F.; Pellereau, E.; Boutoux, G.; Gorbinet, T.; Grente, L.; Bélier, G.; Laurent, B.; Alvarez-Pol, H.; Ayyad, Y.; Benlliure, J.; Caamaño, M.; Audouin, L.; Casarejos, E.; Cortina-Gil, D.; Farget, F.; Fernández-Domínguez, B.; Heinz, A.; Jurado, B.; Kelić-Heil, A.; Kurz, N.; Lindberg, S.; Löher, B.; Nociforo, C.; Paradela, C.; Pietri, S.; Ramos, D.; Rodriguez-Sanchez, J.-L.; Rodrìguez-Tajes, C.; Rossi, D.; Schmidt, K.-H.; Simon, H.; Tassan-Got, L.; Törnqvist, H.; Vargas, J.; Voss, B.; Weick, H.; Yan, Y.

    2016-03-01

    SOFIA (Studies On Fission with Aladin) is a new experimental set-up dedicated to accurate measurement of fission-fragments isotopic yields. It is located at GSI, the only place to use inverse kinematics at relativistic energies in order to study the (γ,f) electromagnetic-induced fission. The SOFIA set-up is a large-acceptance magnetic spectrometer, which allows to fully identify both fission fragments in coincidence on the whole fission-fragment range. This paper will report on fission yields obtained in 234,235,236,238U(γ,f) reactions.

  13. The set-up for forward scattered particle detection at the external microbeam facility of the INFN-LABEC laboratory in Florence

    NASA Astrophysics Data System (ADS)

    Giuntini, L.; Massi, M.; Calusi, S.; Gelli, N.; Castelli, L.; Carraresi, L.; Czelusniak, C.; Fedi, M. E.; Gueli, A. M.; Liccioli, L.; Mandò, P. A.; Mazzinghi, A.; Palla, L.; Ruberto, C.; Taccetti, F.

    2015-04-01

    In the last few years some new implementations and upgrades have been made to the external scanning microbeam of INFN-LABEC laboratory in Florence, enriching the existing PIXE, PIGE, BS, IBIL set-up with complementary techniques, when possible allowing for simultaneous multi-technique analyses. We developed a system, compatible with the existing set-up, for the out-of-vacuum detection of the forward scattered particles. This system makes feasible the external-STIM (Scanning Transmission Ion Microscopy) and external-FS (Forward Scattering), now both available at our beamline. Test measurements are shortly presented.

  14. The Setting-up of Multi-Site School Collaboratives: The Benefits of This Organizational Reform in Terms of Networking Opportunities and Their Effects

    ERIC Educational Resources Information Center

    Mifsud, Denise

    2015-01-01

    This article, which is set within the Maltese education scenario of unfolding decentralization through the setting-up of multi-site school collaboratives (legally termed "colleges") via a policy mandate, explores a particular aspect of this reform--that of "networking". This is examined in terms of the potential for…

  15. ALTERNATIVES FOR REDUCING INSECTICIDES ON COTTON AND CORN: ECONOMIC AND ENVIRONMENTAL IMPACT - SUPPLEMENT 2: PROCEDURES USED IN SETTING UP THE AGRICULTURAL PRODUCTION MODEL

    EPA Science Inventory

    The procedures used in setting up the agricultural production model used in a study of alternatives for reducing insecticides on cotton and corn are described. The major analytical tool used is a spatial equilibrium model of U.S. agriculture. This is a linear programming model th...

  16. Texas A & I University Child Development Associate Training Materials: Book A. Competency A: Setting Up and Maintaining a Safe and Healthy Learning Environment.

    ERIC Educational Resources Information Center

    Texas A and I Univ., Kingsville.

    This volume, the second in a series of seven, contains the four learning modules which focus on the first Child Development Associate (CDA) competency (setting up and maintaining a safe and healthy learning environment) in the performance based curriculum of the Texas A & I Bilingual Bicultural Child Development Associate Training Program. The…

  17. The Objective Borderline Method (OBM): A Probability-Based Model for Setting up an Objective Pass/Fail Cut-Off Score in Medical Programme Assessments

    ERIC Educational Resources Information Center

    Shulruf, Boaz; Turner, Rolf; Poole, Phillippa; Wilkinson, Tim

    2013-01-01

    The decision to pass or fail a medical student is a "high stakes" one. The aim of this study is to introduce and demonstrate the feasibility and practicality of a new objective standard-setting method for determining the pass/fail cut-off score from borderline grades. Three methods for setting up pass/fail cut-off scores were compared: the…

  18. Optimized geometry for bulk coal PGNAA with external moderation of the source neutrons

    NASA Astrophysics Data System (ADS)

    Oliveira, C.; Salgado, J.; Carvalho, F. G.

    1995-10-01

    A simulation study of a PGNAA system for the analysis of coal with a 252Cf neutron source has been carried out using the MCNP code to investigate the effect on the system response of variable thickness, density and composition of the sample when the source is placed at the center of a moderating sphere of polyethylene. Results for different radii of the moderating sphere are reported. The results show that the geometry of the measuring arrangement can be chosen so that the γ count rate/wt % of an arbitrary element (including hydrogen) is independent both of the hydrogen content of the coal, ωH, expressed as a mass fraction, and of the bulk density, d, or volume hydrogen content of the sample νH, at least in the range of ωH-values commonly found in bituminous coals. The system response, defined as the magnitude of the output signal/wt % of an arbitrary element in the coal composition is then independent of composition and bulk density of the coal sample.

  19. Development of a new in-air micro-PIXE set-up with in-vacuum charge measurements in Atomki

    NASA Astrophysics Data System (ADS)

    Török, Zs.; Huszánk, R.; Csedreki, L.; Dani, J.; Szoboszlai, Z.; Kertész, Zs.

    2015-11-01

    A new external microbeam set-up has recently been installed as the extension of the existing microprobe system at the Laboratory of Ion Beam Applications of Atomki, Debrecen, Hungary. The external beam set-up, based on the system of Oxford Microbeams (OM), is equipped with two X-ray detectors for PIXE analysis, a digital microscope, two alignment lasers and a precision XYZ stage for easy and reproducible positioning of the sample. Exit windows with different thicknesses and of different materials can be used according to the actual demands, currently silicon-nitride (Si3N4) film with 200 nm thickness is employed in our laboratory. The first application was demonstrated in the field of archaeometry, on Bronze Age hoards from Hungary.

  20. Developing a virtual reality application for training nuclear power plant operators: setting up a database containing dose rates in the refuelling plant.

    PubMed

    Ródenas, J; Zarza, I; Burgos, M C; Felipe, A; Sánchez-Mayoral, M L

    2004-01-01

    Operators in Nuclear Power Plants can receive high doses during refuelling operations. A training programme for simulating refuelling operations will be useful in reducing the doses received by workers as well as minimising operation time. With this goal in mind, a virtual reality application is developed within the framework of the CIPRES project. The application requires doses, both instantaneous and accumulated, to be displayed at all times during operator training. Therefore, it is necessary to set up a database containing dose rates at every point in the refuelling plant. This database is based on radiological protection surveillance data measured in the plant during refuelling operations. Some interpolation routines have been used to estimate doses through the refuelling plant. Different assumptions have been adopted in order to perform the interpolation and obtain consistent data. In this paper, the procedures developed to set up the dose database for the virtual reality application are presented and analysed. PMID:15266073

  1. Optical Set-Up and Design for Solar Multi-conjugate Adaptive Optics at the 1.6m New Solar Telescope, Big Bear Solar Observatory

    NASA Astrophysics Data System (ADS)

    Moretto, Gil; Langlois, Maud; Goode, Philip; Gorceix, Nicolas; Shumko, Sergey

    2013-12-01

    The Sun is an ideal target for the development and application of Multi-Conjugate Adaptive Optics (MCAO). A solar MCAO system is being developed by the Big Bear Solar Observatory, for the 1.6m New Solar Observatory, with the purpose of extending the corrected science field of view to 1.00Arcmin. A preliminary optical set-up, design and optical performance for such a system is presented and discussed here.

  2. Draft Genome Sequence of Bacillus mesonae FJAT-13985T (=DSM 25968T) for Setting Up Phylogenomics in Genomic Taxonomy of the Bacillus-Like Bacteria

    PubMed Central

    Liu, Guo-hong; Zhu, Yu-jing; Wang, Jie-ping; Che, Jian-mei; Chen, Qian-qian; Chen, Zheng

    2016-01-01

    Bacillus mesonae FJAT-13985T is a Gram-positive, spore-forming, and aerobic bacterium. Here, we report the draft genome sequence of B. mesonae FJAT-13985T with 5,807,726 bp, which will provide useful information for setting up phylogenomics in the genomic taxonomy of the Bacillus-like bacteria, as well as for the functional gene mining and application of B. mesonae FJAT-13985T. PMID:27313309

  3. Draft Genome Sequence of Bacillus simplex DSM 1321 for Setting Up Phylogenomics in Genomic Taxonomy of the Bacillus-Like Bacteria

    PubMed Central

    Liu, Guo-hong; Wang, Jie-ping; Che, Jian-mei; Chen, Qian-qian; Chen, Zheng

    2016-01-01

    Bacillus simplex DSM 1321 is a Gram-positive, spore-forming, and aerobic bacterium. Here, we report the draft genome sequence of B. simplex DSM 1321, with 6,494,937 bp, which will provide useful information for setting up phylogenomics in genomic taxonomy of the Bacillus-like bacteria as well as for the functional gene mining and application of B. simplex DSM 1321. PMID:27340061

  4. Setting up a Prospective Thyroid Biobank for Translational Research: Practical Approach of a Single Institution (2004-2009, Pasteur Hospital, Nice, France).

    PubMed

    Lassalle, Sandra; Hofman, Véronique; Ilie, Marius; Butori, Catherine; Bonnetaud, Christelle; Gaziello, Marie Clotilde; Selva, Eric; Gavric-Tanga, Virginie; Guevara, Nicolas; Castillo, Laurent; Santini, José; Chabannon, Christian; Hofman, Paul

    2011-03-01

    In the last few years, conditions for setting up a human biobank in France have been upgraded by taking into account (1) the new laws and regulations that integrate the ethical and societal dimension of biobanking and delineate the risks for patients associated with the procurement of human cells and tissues, (2) the increasing request by scientists for human samples with proven biological quality and sophisticated sets of annotations, including information produced through the evergrowing use of molecular biology in pathology, and (3) establishment of procedures concerning the safety of the personnel working with biological products. For this purpose, health authorities and national research institutes in France have provided significant support for the set up of biobanks. The present work was conducted to describe how we set up a biobank targeting diseases of a specific organ (thyroid gland), with the aim of rapidly developing translational research projects. The prospective experience of a single institution (Pasteur Hospital, Nice, France) over a 6-year period (2004-2009) is presented from the practical point of view of a surgical pathology laboratory. We describe different procedures required to obtain high-quality thyroid biological resources and clinical annotations. The procedures were established for the management of biological products obtained from 1454 patients who underwent thyroid surgery. The preanalytical steps leading to the storage of frozen specimens were carried out in parallel with diagnostic procedures. As the number of international networks for research programs using biological products is steadily increasing, it is crucial to harmonize the procedures used by biobanks. In this regard, the described thyroid biobank has been set up using criteria established by the French National Cancer Institute (Institut National du Cancer) to guarantee the quality of different collections stored in biobanks. PMID:24850201

  5. SU-E-CAMPUS-T-01: Analysis of the Precision of Patient Set-Up, and Fidelity of the Delivered Dose Distribution in Proton Therapy of Ocular Tumors

    SciTech Connect

    Trofimov, A; Carpenter, K; Shih, HA

    2014-06-15

    Purpose: To quantify daily set-up variations in fractionated proton therapy of ocular melanomas, and to assess the effect on the fidelity of delivered distribution to the plan. Methods: In a typical five-fraction course, daily set-up is achieved by matching the position of fiducial markers in orthogonal radiographs to the images generated by treatment planning program. A patient maintains the required gaze direction voluntarily, without the aid of fixation devices. Confirmation radiographs are acquired to assess intrafractional changes. For this study, daily radiographs were analyzed to determine the daily iso-center position and apparent gaze direction, which were then transferred to the planning system to calculate the dose delivered in individual fractions, and accumulated dose for the entire course. Dose-volume metrics were compared between the planned and accumulated distributions for the tumor and organs at risk, for representative cases that varied by location within the ocular globe. Results: The analysis of the first set of cases (3 posterior, 3 transequatorial and 4 anterior tumors) revealed varying dose deviation patterns, depending on the tumor location. For anterior and posterior tumors, the largest dose increases were observed in the lens and ciliary body, while for the equatorial tumors, macula, optic nerve and disk, were most often affected. The iso-center position error was below 1.3 mm (95%-confidence interval), and the standard deviation of daily polar and azimuthal gaze set-up were 1.5 and 3 degrees, respectively. Conclusion: We quantified interfractional and intrafractional set-up variation, and estimated their effect on the delivered dose for representative cases. Current safety margins are sufficient to maintain the target coverage, however, the dose delivered to critical structures often deviates from the plan. The ongoing analysis will further explore the patterns of dose deviation, and may help to identify particular treatment scenarios

  6. Setting up terminal care units *

    PubMed Central

    Matthews, Bridget

    1980-01-01

    From my experience the main problems found by developing terminal care units have been: initial acceptance from existing medical disciplines; communication difficulties and misunderstandings because of them; mistakes in planning and design, possibly due to lack of experience or attention to detail; occasionally, the appointment of staff that have proved unsuitable; problems in the siting of a unit, usually due to shortage of available land. The ideal site is centrally placed in the community it serves and easily accessible to public transport. PMID:7452580

  7. Swell-generated Set-up and Infragravity Wave Propagation Over a Fringing Coral Reef: Implications for Wave-driven Inundation of Atoll Islands

    NASA Astrophysics Data System (ADS)

    Cheriton, O. M.; Storlazzi, C. D.; Rosenberger, K. J.; Quataert, E.; van Dongeren, A.

    2014-12-01

    The Republic of the Marshall Islands is comprised of 1156 islands on 29 low-lying atolls with a mean elevation of 2 m that are susceptible to sea-level rise and often subjected to overwash during large wave events. A 6-month deployment of wave and tide gauges across two shore-normal sections of north-facing coral reef on the Roi-Namur Island on Kwajalein Atoll was conducted during 2013-2014 to quantify wave dynamics and wave-driven water levels on the fringing coral reef. Wave heights and periods on the reef flat were strongly correlated to the water levels. On the fore reef, the majority of wave energy was concentrated in the incident band (5-25 s); due to breaking at the reef crest, however, the wave energy over the reef flat was dominated by infragravity-band (25-250 s) motions. Two large wave events with heights of 6-8 m at 15 s over the fore reef were observed. During these events, infragravity-band wave heights exceeded the incident band wave heights and approximately 1.0 m of set-up was established over the innermost reef flat. This set-up enabled the propagation of large waves across the reef flat, reaching maximum heights of nearly 2 m on the innermost reef flat adjacent to the toe of the beach. XBEACH models of the instrument transects were able to replicate the incident waves, infragravity waves, and wave-driven set-up across the reef when the hydrodynamic roughness of the reef was correctly parameterized. These events led to more than 3 m of wave-driven run-up and inundation of the island that drove substantial morphological change to the beach face.

  8. River Modeling in Large and Ungauged Basins: Experience of Setting up the HEC RAS Model over the Ganges-Brahmaputra-Meghna Basins

    NASA Astrophysics Data System (ADS)

    Hossain, F.; Maswood, M.

    2014-12-01

    River modeling is the processing of setting up a physically-based hydrodynamic model that can simulate the water flow dynamics of a stream network against time varying boundary conditions. Such river models are an important component of any flood forecasting system that forecasts river levels in flood prone regions. However, many large river basins in the developing world such as the Ganges, Brahmaputra, Meghna (GBM), Indus, Irrawaddy, Salween, Mekong and Niger are mostly ungauged. Such large basins lack the necessary in-situ measurements of river bed depth/slope, bathymetry (river cross section), floodplain mapping and boundary condition flows for forcing a river model. For such basins, proxy approaches relying mostly on remote sensing data from space platforms are the only alternative. In this study, we share our experience of setting up the widely-used 1-D river model over the entire GBM basin and its stream network. Good quality in-situ measurements of river hydraulics (cross section, slope, flow) was available only for the downstream and flood prone region of the basin, which comprises only 7% of the basin area. For the remaining 93% of the basin area, we resorted to the use of data from the following satellite sensors to build a workable river model: a) Shuttle Radar Topography Mission (SRTM) for deriving bed slope; b) LANDSAT/MODIS for updating river network and flow direction generated by elevation data; c) radar altimetry data to build depth versus width relationship at river locations; d) satellite precipitation based hydrologic modeling of lateral flows into main stem rivers. In addition, we referred to an extensive body of literature to estimate the prevailing baseline hydraulics of rivers in the ungauged region. We measured success of our approach by systematically testing how well the basin-wide river model could simulate river level dynamics at two measured locations inside Bangladesh. Our experience of river modeling was replete with numerous

  9. SU-C-204-06: Surface Imaging for the Set-Up of Proton Post-Mastectomy Chestwall Irradiation: Gated Images Vs Non Gated Images

    SciTech Connect

    Batin, E; Depauw, N; MacDonald, S; Lu, H

    2015-06-15

    Purpose: Historically, the set-up for proton post-mastectomy chestwall irradiation at our institution started with positioning the patient using tattoos and lasers. One or more rounds of orthogonal X-rays at gantry 0° and beamline X-ray at treatment gantry angle were then taken to finalize the set-up position. As chestwall targets are shallow and superficial, surface imaging is a promising tool for set-up and needs to be investigated Methods: The orthogonal imaging was entirely replaced by AlignRT™ (ART) images. The beamline X-Ray image is kept as a confirmation, based primarily on three opaque markers placed on skin surface instead of bony anatomy. In the first phase of the process, ART gated images were used to set-up the patient and the same specific point of the breathing curve was used every day. The moves (translations and rotations) computed for each point of the breathing curve during the first five fractions were analyzed for ten patients. During a second phase of the study, ART gated images were replaced by ART non-gated images combined with real-time monitoring. In both cases, ART images were acquired just before treatment to access the patient position compare to the non-gated CT. Results: The average difference between the maximum move and the minimum move depending on the chosen breathing curve point was less than 1.7 mm for all translations and less than 0.7° for all rotations. The average position discrepancy over the course of treatment obtained by ART non gated images combined to real-time monitoring taken before treatment to the planning CT were smaller than the average position discrepancy obtained using ART gated images. The X-Ray validation images show similar results with both ART imaging process. Conclusion: The use of ART non gated images combined with real time imaging allows positioning post-mastectomy chestwall patients in less than 3 mm / 1°.

  10. Focus stacking: Comparing commercial top-end set-ups with a semi-automatic low budget approach. A possible solution for mass digitization of type specimens.

    PubMed

    Brecko, Jonathan; Mathys, Aurore; Dekoninck, Wouter; Leponce, Maurice; VandenSpiegel, Didier; Semal, Patrick

    2014-01-01

    In this manuscript we present a focus stacking system, composed of commercial photographic equipment. The system is inexpensive compared to high-end commercial focus stacking solutions. We tested this system and compared the results with several different software packages (CombineZP, Auto-Montage, Helicon Focus and Zerene Stacker). We tested our final stacked picture with a picture obtained from two high-end focus stacking solutions: a Leica MZ16A with DFC500 and a Leica Z6APO with DFC290. Zerene Stacker and Helicon Focus both provided satisfactory results. However, Zerene Stacker gives the user more possibilities in terms of control of the software, batch processing and retouching. The outcome of the test on high-end solutions demonstrates that our approach performs better in several ways. The resolution of the tested extended focus pictures is much higher than those from the Leica systems. The flash lighting inside the Ikea closet creates an evenly illuminated picture, without struggling with filters, diffusers, etc. The largest benefit is the price of the set-up which is approximately € 3,000, which is 8 and 10 times less than the LeicaZ6APO and LeicaMZ16A set-up respectively. Overall, this enables institutions to purchase multiple solutions or to start digitising the type collection on a large scale even with a small budget. PMID:25589866

  11. Focus stacking: Comparing commercial top-end set-ups with a semi-automatic low budget approach. A possible solution for mass digitization of type specimens

    PubMed Central

    Brecko, Jonathan; Mathys, Aurore; Dekoninck, Wouter; Leponce, Maurice; VandenSpiegel, Didier; Semal, Patrick

    2014-01-01

    Abstract In this manuscript we present a focus stacking system, composed of commercial photographic equipment. The system is inexpensive compared to high-end commercial focus stacking solutions. We tested this system and compared the results with several different software packages (CombineZP, Auto-Montage, Helicon Focus and Zerene Stacker). We tested our final stacked picture with a picture obtained from two high-end focus stacking solutions: a Leica MZ16A with DFC500 and a Leica Z6APO with DFC290. Zerene Stacker and Helicon Focus both provided satisfactory results. However, Zerene Stacker gives the user more possibilities in terms of control of the software, batch processing and retouching. The outcome of the test on high-end solutions demonstrates that our approach performs better in several ways. The resolution of the tested extended focus pictures is much higher than those from the Leica systems. The flash lighting inside the Ikea closet creates an evenly illuminated picture, without struggling with filters, diffusers, etc. The largest benefit is the price of the set-up which is approximately € 3,000, which is 8 and 10 times less than the LeicaZ6APO and LeicaMZ16A set-up respectively. Overall, this enables institutions to purchase multiple solutions or to start digitising the type collection on a large scale even with a small budget. PMID:25589866

  12. Determining the reliability of a custom built seated stadiometry set-up for measuring spinal height in participants with chronic low back pain.

    PubMed

    Steele, James; Bruce-Low, Stewart; Smith, Dave; Jessop, David; Osborne, Neil

    2016-03-01

    Indirect measurement of disc hydration can be obtained through measures of spinal height using stadiometry. However, specialised stadiometers for this are often custom-built and expensive. Generic wall-mounted stadiometers alternatively are common in clinics and laboratories. This study examined the reliability of a custom set-up utilising a wall-mounted stadiometer for measurement of spinal height using custom built wall mounted postural rods. Twelve participants with non-specific chronic low back pain (CLBP; females n = 5, males n = 7) underwent measurement of spinal height on three separate consecutive days at the same time of day where 10 measurements were taken at 20 s intervals. Comparisons were made using repeated measures analysis of variance for 'trial' and 'gender'. There were no significant effects by trial or interaction effects of trial x gender. Intra-individual absolute standard error of measurement (SEM) was calculated for spinal height using the first of the 10 measures, the average of 10 measures, the total shrinkage, and the rate of shrinkage across the 10 measures examined as the slope of the curve when a linear regression was fitted. SEMs were 3.1 mm, 2.8 mm, 2.6 mm and 0.212, respectively. Absence of significant differences between trials and the reported SEMs suggests this custom set-up for measuring spinal height changes is suitable use as an outcome measure in either research or clinical practice in participants with CLBP. PMID:26493099

  13. Influence of set-up conditions of exposure indicators on the estimate of short-term associations between urban pollution and mortality.

    PubMed

    Filleul, Laurent; Zeghnoun, Abdelkrim; Cassadou, Sylvie; Declercq, Christophe; Eilstein, Daniel; le Tertre, Alain; Medina, Sylvia; Pascal, Laurence; Prouvost, Hélène; Saviuc, Philippe; Quénel, Philippe

    2006-02-15

    In the past few years many studies on air pollution and health based on time series have been carried out. Yet, this approach does not assess exposure to air pollution at an individual level but it is based on ambient concentrations measured by air quality monitoring networks. Questions on the estimates of exposure to pollutants have been raised, in particular the fact that background measuring stations only have been considered in the set up of pollution indicators. To assess the impact of exposure indicator characteristics on the results of time series analysis, two series (black smoke and sulfur dioxide, respectively) of exposure indicators to urban air pollution were set up taking into account a growing part of proximity measures (industrial sources) available in the studied urban area (Le Havre, France). For each pollutant, indicators distributions were almost similar, especially for black smoke. Whatever the pollutant, the most obvious heterogeneity could be observed between the 100% background indicator and the indicator including the arithmetic mean for all the stations (50% background stations and 50% proximity stations). Then the sensitivity of the associations between mortality and air pollution to these indicators was studied. These indicators did not show statistically significant differences in the estimated excess risk. Yet, confidence intervals were more statistically significant as the contribution of proximity stations was more substantial, in particular for SO2. To conclude, the use of proximity measurements did not influence dramatically on the mean estimates of the association between air pollution and mortality indicators in Le Havre. Therefore it does not seem relevant to include the data provided by the proximity stations in the urban exposure indicators within the context of the epidemiology monitoring system. PMID:16442434

  14. Experimental Set Up of P300 Based Brain Computer Interface Using a Bioamplifier and BCI2000 System for Patients with Spinal Cord Injury

    PubMed Central

    Jeon, Hyeongseok

    2015-01-01

    Objective Brain computer interface (BCI) is one of the most promising technologies for helping people with neurological disorders. Most current BCI systems are relatively expensive and difficult to set up. Therefore, we developed a P300-based BCI system with a cheap bioamplifier and open source software. The purpose of this study was to describe the setup process of the system and preliminary experimental results. Methods Ten spinal cord-injured patients were recruited. We used a sixteen-channel EEG(KT88-1016, Contec, China) and BCI2000 software (Wadsworth center, NY, USA). Subjects were asked to spell a 5-character word using the P300-based BCI system with 10 minutes of training. EEG data were acquired during the experiment. After subjects spelled the word for ten trials, the spelling accuracy and information transfer rate (ITR) were obtained in each patients. Results All subjects performed the experiment without difficulty. The mean accuracy was 59.4±22.8%. The spelling accuracy reversely correlated with the age. Younger subjects spelled with higher accuracy than older subjects (p=0.018). However, sex, injury level, time since injury and ASIA scale were not correlated with the accuracy. The mean of ITR was 2.26±1.22 bit/min. Conclusion This study showed that a BCI system can be set up inexpensively with a low-price bioamplifier and open-source software. The spelling accuracy was moderately achieved with our system. P300-based BCI is useful in young patients, but modification is necessary in old patients who have low ability of recognition and concentration. PMID:26512264

  15. Experimental illumination of natural habitat—an experimental set-up to assess the direct and indirect ecological consequences of artificial light of different spectral composition

    PubMed Central

    Spoelstra, Kamiel; van Grunsven, Roy H. A.; Donners, Maurice; Gienapp, Phillip; Huigens, Martinus E.; Slaterus, Roy; Berendse, Frank; Visser, Marcel E.; Veenendaal, Elmar

    2015-01-01

    Artificial night-time illumination of natural habitats has increased dramatically over the past few decades. Generally, studies that assess the impact of artificial light on various species in the wild make use of existing illumination and are therefore correlative. Moreover, studies mostly focus on short-term consequences at the individual level, rather than long-term consequences at the population and community level—thereby ignoring possible unknown cascading effects in ecosystems. The recent change to LED lighting has opened up the exciting possibility to use light with a custom spectral composition, thereby potentially reducing the negative impact of artificial light. We describe here a large-scale, ecosystem-wide study where we experimentally illuminate forest-edge habitat with different spectral composition, replicated eight times. Monitoring of species is being performed according to rigid protocols, in part using a citizen-science-based approach, and automated where possible. Simultaneously, we specifically look at alterations in behaviour, such as changes in activity, and daily and seasonal timing. In our set-up, we have so far observed that experimental lights facilitate foraging activity of pipistrelle bats, suppress activity of wood mice and have effects on birds at the community level, which vary with spectral composition. Thus far, we have not observed effects on moth populations, but these and many other effects may surface only after a longer period of time. PMID:25780241

  16. A Controlled Design of Aligned and Random Nanofibers for 3D Bi-functionalized Nerve Conduits Fabricated via a Novel Electrospinning Set-up

    PubMed Central

    Kim, Jeong In; Hwang, Tae In; Aguilar, Ludwig Erik; Park, Chan Hee; Kim, Cheol Sang

    2016-01-01

    Scaffolds made of aligned nanofibers are favorable for nerve regeneration due to their superior nerve cell attachment and proliferation. However, it is challenging not only to produce a neat mat or a conduit form with aligned nanofibers but also to use these for surgical applications as a nerve guide conduit due to their insufficient mechanical strength. Furthermore, no studies have been reported on the fabrication of aligned nanofibers and randomly-oriented nanofibers on the same mat. In this study, we have successfully produced a mat with both aligned and randomly-oriented nanofibers by using a novel electrospinning set up. A new conduit with a highly-aligned electrospun mat is produced with this modified electrospinning method, and this proposed conduit with favorable features, such as selective permeability, hydrophilicity and nerve growth directional steering, were fabricated as nerve guide conduits (NGCs). The inner surface of the nerve conduit is covered with highly aligned electrospun nanofibers and is able to enhance the proliferation of neural cells. The central part of the tube is double-coated with randomly-oriented nanofibers over the aligned nanofibers, strengthening the weak mechanical strength of the aligned nanofibers. PMID:27021221

  17. Fluorescence multi-scale endoscopy and its applications in the study and diagnosis of gastro-intestinal diseases: set-up design and software implementation

    NASA Astrophysics Data System (ADS)

    Gómez-García, Pablo Aurelio; Arranz, Alicia; Fresno, Manuel; Desco, Manuel; Mahmood, Umar; Vaquero, Juan José; Ripoll, Jorge

    2015-06-01

    Endoscopy is frequently used in the diagnosis of several gastro-intestinal pathologies as Crohn disease, ulcerative colitis or colorectal cancer. It has great potential as a non-invasive screening technique capable of detecting suspicious alterations in the intestinal mucosa, such as inflammatory processes. However, these early lesions usually cannot be detected with conventional endoscopes, due to lack of cellular detail and the absence of specific markers. Due to this lack of specificity, the development of new endoscopy technologies, which are able to show microscopic changes in the mucosa structure, are necessary. We here present a confocal endomicroscope, which in combination with a wide field fluorescence endoscope offers fast and specific macroscopic information through the use of activatable probes and a detailed analysis at cellular level of the possible altered tissue areas. This multi-modal and multi-scale imaging module, compatible with commercial endoscopes, combines near-infrared fluorescence (NIRF) measurements (enabling specific imaging of markers of disease and prognosis) and confocal endomicroscopy making use of a fiber bundle, providing a cellular level resolution. The system will be used in animal models exhibiting gastro-intestinal diseases in order to analyze the use of potential diagnostic markers in colorectal cancer. In this work, we present in detail the set-up design and the software implementation in order to obtain simultaneous RGB/NIRF measurements and short confocal scanning times.

  18. Measurement of maximum skin dose in interventional radiology and cardiology and challenges in the set-up of European alert thresholds.

    PubMed

    Farah, J; Trianni, A; Carinou, E; Ciraj-Bjelac, O; Clairand, I; Dabin, J; De Angelis, C; Domienik, J; Jarvinen, H; Kopec, R; Majer, M; Malchair, F; Negri, A; Novák, L; Siiskonen, T; Vanhavere, F; Knežević, Ž

    2015-04-01

    To help operators acknowledge patient dose during interventional procedures, EURADOS WG-12 focused on measuring patient skin dose using XR-RV3 gafchromic films, thermoluminescent detector (TLD) pellets or 2D TL foils and on investigating possible correlation to the on-line dose indicators such as fluoroscopy time, Kerma-area product (KAP) and cumulative air Kerma at reference point (CK). The study aims at defining non-centre-specific European alert thresholds for skin dose in three interventional procedures: chemoembolization of the liver (CE), neuroembolization (NE) and percutaneous coronary interventions (PCI). Skin dose values of >3 Gy (ICRP threshold for skin injuries) were indeed measured in these procedures confirming the need for dose indicators that correlate with maximum skin dose (MSD). However, although MSD showed fairly good correlation with KAP and CK, several limitations were identified challenging the set-up of non-centre-specific European alert thresholds. This paper presents preliminary results of this wide European measurement campaign and focuses on the main challenges in the definition of European alert thresholds. PMID:25316909

  19. Experimental illumination of natural habitat--an experimental set-up to assess the direct and indirect ecological consequences of artificial light of different spectral composition.

    PubMed

    Spoelstra, Kamiel; van Grunsven, Roy H A; Donners, Maurice; Gienapp, Phillip; Huigens, Martinus E; Slaterus, Roy; Berendse, Frank; Visser, Marcel E; Veenendaal, Elmar

    2015-05-01

    Artificial night-time illumination of natural habitats has increased dramatically over the past few decades. Generally, studies that assess the impact of artificial light on various species in the wild make use of existing illumination and are therefore correlative. Moreover, studies mostly focus on short-term consequences at the individual level, rather than long-term consequences at the population and community level-thereby ignoring possible unknown cascading effects in ecosystems. The recent change to LED lighting has opened up the exciting possibility to use light with a custom spectral composition, thereby potentially reducing the negative impact of artificial light. We describe here a large-scale, ecosystem-wide study where we experimentally illuminate forest-edge habitat with different spectral composition, replicated eight times. Monitoring of species is being performed according to rigid protocols, in part using a citizen-science-based approach, and automated where possible. Simultaneously, we specifically look at alterations in behaviour, such as changes in activity, and daily and seasonal timing. In our set-up, we have so far observed that experimental lights facilitate foraging activity of pipistrelle bats, suppress activity of wood mice and have effects on birds at the community level, which vary with spectral composition. Thus far, we have not observed effects on moth populations, but these and many other effects may surface only after a longer period of time. PMID:25780241

  20. Cold test with a benchtop set-up for fluidized bed reactor using quartz sand to simulate gasification of coal cokes by concentrated solar radiation

    NASA Astrophysics Data System (ADS)

    Gokon, Nobuyuki; Tanabe, Tomoaki; Shimizu, Tadaaki; Kodama, Tatsuya

    2016-05-01

    The impacts of internal circulation of a mixture of coal-coke particles and quartz sand on the fluidization state in a fluidized bed reactor are investigated by a cold test with a benchtop set-up in order to design 10-30 kWth scale prototype windowed fluidized-bed reactor. Firstly, a basic relationship between pressure loss of inlet gas and gas velocity was experimentally examined using quartz sand with different particle sizes by a small-scale quartz tube with a distributor at ambient pressure and temperature. Based on the results, an appropriate particle range of quartz sand and layer height/layer diameter ratio (L/D ratio) was determined for a design of the fluidized bed reactor. Secondly, a windowed reactor mock-up was designed and fabricated for solar coke gasification using quartz sand as a bed material. The pressure loss between the inlet and outlet gases was examined, and descending cokes and sand particles on the sidewall of the reactor was observed in the reactor mock-up. The moving velocity and distance of descending particles/sands from the top to bottom of fluidized bed were measured by the visual observation of the colored tracer particles on outside wall of the reactor.

  1. A Controlled Design of Aligned and Random Nanofibers for 3D Bi-functionalized Nerve Conduits Fabricated via a Novel Electrospinning Set-up.

    PubMed

    Kim, Jeong In; Hwang, Tae In; Aguilar, Ludwig Erik; Park, Chan Hee; Kim, Cheol Sang

    2016-01-01

    Scaffolds made of aligned nanofibers are favorable for nerve regeneration due to their superior nerve cell attachment and proliferation. However, it is challenging not only to produce a neat mat or a conduit form with aligned nanofibers but also to use these for surgical applications as a nerve guide conduit due to their insufficient mechanical strength. Furthermore, no studies have been reported on the fabrication of aligned nanofibers and randomly-oriented nanofibers on the same mat. In this study, we have successfully produced a mat with both aligned and randomly-oriented nanofibers by using a novel electrospinning set up. A new conduit with a highly-aligned electrospun mat is produced with this modified electrospinning method, and this proposed conduit with favorable features, such as selective permeability, hydrophilicity and nerve growth directional steering, were fabricated as nerve guide conduits (NGCs). The inner surface of the nerve conduit is covered with highly aligned electrospun nanofibers and is able to enhance the proliferation of neural cells. The central part of the tube is double-coated with randomly-oriented nanofibers over the aligned nanofibers, strengthening the weak mechanical strength of the aligned nanofibers. PMID:27021221

  2. Awareness assessment of harmful effects of mercury in a health care set-up in India: A survey-based study.

    PubMed

    Halder, Nabanita; Peshin, Sharda Shah; Pandey, Ravindra Mohan; Gupta, Yogendra Kumar

    2015-12-01

    Mercury, one of the most toxic heavy metals, is ubiquitous in environment. The adverse health impact of mercury on living organisms is well known. The health care facilities are one of the important sources of mercury release into the atmosphere as mercury items are extensively used in hospitals. To assess the awareness about mercury toxicity and the knowledge of proper handling and disposal of mercury-containing items in health care set-up, a questionnaire-based survey was carried out amongst doctors (n = 835), nurses (n = 610) and technicians (n = 393) in government hospitals, corporate hospitals and primary health care centres in the Indian states of Delhi, Uttar Pradesh and Haryana. The study was conducted using a tool-containing pretested structured multiple-choice questionnaire. Analysis of the results using STATA 11.1 software highlighted that overall awareness was more in corporate sector. However, percentage range of knowledge of respondents irrespective of health care sector was only between 20 and 40%. Despite the commitment of various hospitals to be mercury free, mercury containing-thermometer/sphygmomanometer are still preferred by health professionals. The likely reasons are availability, affordability, accuracy and convenience in use. There is an urgent need for source reduction, recycling and waste minimization. Emphasis must be laid on mercury alternative products, education and training of health personnel and public at large, about correct handling and proper clean up of spills. PMID:23698903

  3. Setting Up a Bioluminescence Resonance Energy Transfer High throughput Screening Assay to Search for Protein/Protein Interaction Inhibitors in Mammalian Cells

    PubMed Central

    Couturier, Cyril; Deprez, Benoit

    2012-01-01

    Each step of the cell life and its response or adaptation to its environment are mediated by a network of protein/protein interactions termed “interactome.” Our knowledge of this network keeps growing due to the development of sensitive techniques devoted to study these interactions. The bioluminescence resonance energy transfer (BRET) technique was primarily developed to allow the dynamic monitoring of protein/protein interactions (PPI) in living cells, and has widely been used to study receptor activation by intra- or extra-molecular conformational changes within receptors and activated complexes in mammal cells. Some interactions are described as crucial in human pathological processes, and a new class of drugs targeting them has recently emerged. The BRET method is well suited to identify inhibitors of PPI and here is described why and how to set up and optimize a high throughput screening assay based on BRET to search for such inhibitory compounds. The different parameters to take into account when developing such BRET assays in mammal cells are reviewed to give general guidelines: considerations on the targeted interaction, choice of BRET version, inducibility of the interaction, kinetic of the monitored interaction, and of the BRET reading, influence of substrate concentration, number of cells and medium composition used on the Z′ factor, and expected interferences from colored or fluorescent compounds. PMID:22973258

  4. A novel 15N tracer approach for the quantification of N2 and N2O emissions from soil incubations in a completely automated laboratory set up

    NASA Astrophysics Data System (ADS)

    Scheer, Clemens; Dannenmann, Michael; Meier, Rudolf

    2015-04-01

    The microbial mediated production of nitrous oxide (N2O) and its reduction to dinitrogen (N2) via denitrification represents a loss of nitrogen (N) from fertilised agro-ecosystems to the atmosphere. Although denitrification has received great interest by biogeochemists in the last decades, the magnitude of N2lossesand related N2:N2O ratios from soils still are largely unknown due to methodical constraints. We present a novel 15N tracer approach, based on a previous developed tracer method to study denitrification in pure bacterial cultures which was modified for the use on soil incubations in a completely automated laboratory set up. The method uses a background air in the incubation vessels that is replaced with a helium-oxygen gas mixture with a 50-fold reduced N2 background (2 % v/v). This method allows for a direct and sensitive quantification of the N2 and N2O emissions from the soil with isotope-ratio mass spectrometry after 15N labelling of denitrification N substrates and minimises the sensitivity to the intrusion of atmospheric N2 at the same time. The incubation set up was used to determine the influence of different soil moisture levels on N2 and N2O emissions from a sub-tropical pasture soil in Queensland/Australia. The soil was labelled with an equivalent of 50 μg-N per gram dry soil by broadcast application of KNO3solution (4 at.% 15N) and incubated for 3 days at 80% and 100% water filled pore space (WFPS), respectively. The headspace of the incubation vessel was sampled automatically over 12hrs each day and 3 samples (0, 6, and 12 hrs after incubation start) of headspace gas analysed for N2 and N2O with an isotope-ratio mass spectrometer (DELTA V Plus, Thermo Fisher Scientific, Bremen, Germany(. In addition, the soil was analysed for 15N NO3- and NH4+ using the 15N diffusion method, which enabled us to obtain a complete N balance. The method proved to be highly sensitive for N2 and N2O emissions detecting N2O emissions ranging from 20 to 627 μN kg

  5. Fish welfare assurance system: initial steps to set up an effective tool to safeguard and monitor farmed fish welfare at a company level.

    PubMed

    van de Vis, J W; Poelman, M; Lambooij, E; Bégout, M-L; Pilarczyk, M

    2012-02-01

    The objective was to take a first step in the development of a process-oriented quality assurance (QA) system for monitoring and safeguarding of fish welfare at a company level. A process-oriented approach is focused on preventing hazards and involves establishment of critical steps in a process that requires careful control. The seven principles of the Hazard Analysis Critical Control Points (HACCP) concept were used as a framework to establish the QA system. HACCP is an internationally agreed approach for management of food safety, which was adapted for the purpose of safeguarding and monitoring the welfare of farmed fish. As the main focus of this QA system is farmed fish welfare assurance at a company level, it was named Fish Welfare Assurance System (FWAS). In this paper we present the initial steps of setting up FWAS for on growing of sea bass (Dicentrarchus labrax), carp (Cyprinus carpio) and European eel (Anguilla anguilla). Four major hazards were selected, which were fish species dependent. Critical Control Points (CCPs) that need to be controlled to minimize or avoid the four hazards are presented. For FWAS, monitoring of CCPs at a farm level is essential. For monitoring purposes, Operational Welfare Indicators (OWIs) are needed to establish whether critical biotic, abiotic, managerial and environmental factors are controlled. For the OWIs we present critical limits/target values. A critical limit is the maximum or minimum value to which a factor must be controlled at a critical control point to prevent, eliminate or reduce a hazard to an acceptable level. For managerial factors target levels are more appropriate than critical limits. Regarding the international trade of farmed fish products, we propose that FWAS needs to be standardized in aquaculture chains. For this standardization a consensus on the concept of fish welfare, methods to assess welfare objectively and knowledge on the needs of farmed fish are required. PMID:22278705

  6. SU-E-J-172: Bio-Physical Effects of Patients Set-Up Errors According to Whole Breast Irradiation Techniques

    SciTech Connect

    Lee, S; Suh, T; Park, S; Kim, M; Lee, M; Park, J

    2015-06-15

    Purpose: The dose-related effects of patient setup errors on biophysical indices were evaluated for conventional wedge (CW) and field-in-field (FIF) whole breast irradiation techniques. Methods: The treatment plans for 10 patients receiving whole left breast irradiation were retrospectively selected. Radiobiological and physical effects caused by dose variations were evaluated by shifting the isocenters and gantry angles of the treatment plans. Dose-volume histograms of the planning target volume (PTV), heart, and lungs were generated, and conformity index (CI), homogeneity index (HI), tumor control probability (TCP), and normal tissue complication probability (NTCP) were determined. Results: For “isocenter shift plan” with posterior direction, the D95 of the PTV decreased by approximately 15% and the TCP of the PTV decreased by approximately 50% for the FIF technique and by 40% for the CW; however, the NTCPs of the lungs and heart increased by about 13% and 1%, respectively, for both techniques. Increasing the gantry angle decreased the TCPs of the PTV by 24.4% (CW) and by 34% (FIF). The NTCPs for the two techniques differed by only 3%. In case of CW, the CIs and HIs were much higher than that of the FIF in all cases. It had a significant difference between two techniques (p<0.01). According to our results, however, the FIF had more sensitive response by set up errors rather than CW in bio-physical aspects. Conclusions: The radiobiological-based analysis can detect significant dosimetric errors then, can provide a practical patient quality assurance method to guide the radiobiological and physical effects.

  7. Electronic portal imaging vs kilovoltage imaging in fiducial marker image-guided radiotherapy for prostate cancer: an analysis of set-up uncertainties

    PubMed Central

    Gill, S; Thomas, J; Fox, C; Kron, T; Thompson, A; Chander, S; Williams, S; Tai, K H; Duchesne, G; Foroudi, F

    2012-01-01

    Objectives The purpose of this study was to compare interfraction prostate displacement data between electronic portal imaging (EPI) and kilovoltage imaging (KVI) treatment units and discuss the impact of any difference on margin calculations for prostate cancer image-guided radiotherapy (IGRT). Methods Prostate interfraction displacement data was collected prospectively for the first 4 fractions in 333 patients treated with IGRT with daily pre-treatment EPI or KVI orthogonal imaging. Displacement was recorded in the anteroposterior (AP), left–right (LR) and superoinferior (SI) directions. The proportion of displacement <3 mm and the difference in median absolute displacements were calculated in all directions. Results 1088 image pairs were analysed in total, 448 by EPI and 640 by KVI. There were 23% (95% confidence interval [CI] 18–28%) more displacements under 3 mm for EPI than for KVI in the AP direction, 14% (95% CI 10–19%) more in the LR direction and 10% (95% CI 5–15%) more in the SI direction. The differences in absolute median displacement (KVI>EPI) were AP 1 mm, LR 1 mm and SI 0.5 mm. Wilcoxon rank-sum test showed that distributions were significantly different for all three dimensions (p<0.0001 for AP and LR and p=0.02 for SI). Conclusion EPI has a statistically significant smaller set-up error distribution than KVI. We would expect that, because fiducial marker imaging is less clear for EPI, the clinical target volume to planning target volume margin would be greater when using IGRT; however, relying wholly on displacement data gives the opposite result. We postulate that this is owing to observer bias, which is not accounted for in margin calculation formulas. PMID:21976627

  8. An experimental set-up to apply polarization modulation to infrared reflection absorption spectroscopy for improved in situ studies of atmospheric corrosion processes

    SciTech Connect

    Wiesinger, R.; Schade, U.; Kleber, Ch.; Schreiner, M.

    2014-06-15

    A new set-up for improved monitoring of atmospheric corrosion processes in situ and in real-time is presented. To characterize chemical structures of thin films on metal surfaces surface sensitive analytical techniques are required. One possible technique is Infrared Reflection Absorption Spectroscopy (IRRAS) which has become an established method to investigate surface corrosion films of thicknesses less than 200 nm. However, there are limitations related to the sensitivity of these measurements, in case of investigating ultrathin films or absorption bands of interest, surface species are superimposed by atmospheric background absorption, which changes during in situ measurements in ambient atmospheres. These difficulties of in situ surface reflection measurements can be eliminated by availing the polarization selectivity of adsorbed surface species. At grazing angles of incidence the absorption of p-polarized infrared radiation by thin surface films on metals is enhanced, while the absorption of s-polarized light by this film is nearly zero. This different behavior of the polarization properties leads to strong selection rules at the surface and can therefore be used to identify molecules adsorbed on metal surfaces. Polarization Modulation (PM) of the infrared (IR) light takes advantage of this disparity of polarization on sample surfaces and in combination with IRRAS yielding a very sensitive and surface-selective method for obtaining IR spectra of ultra-thin films on metal surfaces. An already existing in situ IRRAS/Quartz Crystal Microbalance weathering cell was combined with PM and evaluated according to its applicability to study in situ atmospheric corrosion processes. First real-time measurements on silver samples exposed to different atmospheres were performed showing the advantage of PM-IRRAS compared to conventional IRRAS for such investigations.

  9. Analysis of Regional Timelines To Set Up a Global Phase III Clinical Trial in Breast Cancer: The Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization Experience

    PubMed Central

    de Azambuja, Evandro; Bradbury, Ian; Saini, Kamal S.; Bines, José; Simon, Sergio D.; Dooren, Veerle Van; Aktan, Gursel; Pritchard, Kathleen I.; Wolff, Antonio C.; Smith, Ian; Jackisch, Christian; Lang, Istvan; Untch, Michael; Boyle, Frances; Xu, Binghe; Baselga, Jose; Perez, Edith A.; Piccart-Gebhart, Martine

    2013-01-01

    Purpose. This study measured the time taken for setting up the different facets of Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization (ALTTO), an international phase III study being conducted in 44 participating countries. Methods. Time to regulatory authority (RA) approval, time to ethics committee/institutional review board (EC/IRB) approval, time from study approval by EC/IRB to first randomized patient, and time from first to last randomized patient were prospectively collected in the ALTTO study. Analyses were conducted by grouping countries into either geographic regions or economic classes as per the World Bank's criteria. Results. South America had a significantly longer time to RA approval (median: 236 days, range: 21–257 days) than Europe (median: 52 days, range: 0–151 days), North America (median: 26 days, range: 22–30 days), and Asia-Pacific (median: 62 days, range: 37–75 days). Upper-middle economies had longer times to RA approval (median: 123 days, range: 21–257 days) than high-income (median: 47 days, range: 0–112 days) and lower-middle income economies (median: 57 days, range: 37–62 days). No significant difference was observed for time to EC/IRB approval across the studied regions (median: 59 days, range 0–174 days). Overall, the median time from EC/IRB approval to first recruited patient was 169 days (range: 26–412 days). Conclusion. This study highlights the long time intervals required to activate a global phase III trial. Collaborative research groups, pharmaceutical industry sponsors, and regulatory authorities should analyze the current system and enter into dialogue for optimizing local policies. This would enable faster access of patients to innovative therapies and enhance the efficiency of clinical research. PMID:23359433

  10. In Search of the Economic Sustainability of Hadron Therapy: The Real Cost of Setting Up and Operating a Hadron Facility

    SciTech Connect

    Vanderstraeten, Barbara; Verstraete, Jan; De Croock, Roger; De Neve, Wilfried; Lievens, Yolande

    2014-05-01

    Purpose: To determine the treatment cost and required reimbursement for a new hadron therapy facility, considering different technical solutions and financing methods. Methods and Materials: The 3 technical solutions analyzed are a carbon only (COC), proton only (POC), and combined (CC) center, each operating 2 treatment rooms and assumed to function at full capacity. A business model defines the required reimbursement and analyzes the financial implications of setting up a facility over time; activity-based costing (ABC) calculates the treatment costs per type of patient for a center in a steady state of operation. Both models compare a private, full-cost approach with public sponsoring, only taking into account operational costs. Results: Yearly operational costs range between €10.0M (M = million) for a publicly sponsored POC to €24.8M for a CC with private financing. Disregarding inflation, the average treatment cost calculated with ABC (COC: €29,450; POC: €46,342; CC: €46,443 for private financing; respectively €16,059, €28,296, and €23,956 for public sponsoring) is slightly lower than the required reimbursement based on the business model (between €51,200 in a privately funded POC and €18,400 in COC with public sponsoring). Reimbursement for privately financed centers is very sensitive to a delay in commissioning and to the interest rate. Higher throughput and hypofractionation have a positive impact on the treatment costs. Conclusions: Both calculation methods are valid and complementary. The financially most attractive option of a publicly sponsored COC should be balanced to the clinical necessities and the sociopolitical context.