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Sample records for icnirp reference level

  1. Children and adults exposed to electromagnetic fields at the ICNIRP reference levels: theoretical assessment of the induced peak temperature increase.

    PubMed

    Bakker, J F; Paulides, M M; Neufeld, E; Christ, A; Kuster, N; van Rhoon, G C

    2011-08-07

    To avoid potentially adverse health effects of electromagnetic fields (EMF), the International Commission on Non-Ionizing Radiation Protection (ICNIRP) has defined EMF reference levels. Restrictions on induced whole-body-averaged specific absorption rate (SAR(wb)) are provided to keep the whole-body temperature increase (T(body, incr)) under 1 °C during 30 min. Additional restrictions on the peak 10 g spatial-averaged SAR (SAR(10g)) are provided to prevent excessive localized tissue heating. The objective of this study is to assess the localized peak temperature increase (T(incr, max)) in children upon exposure at the reference levels. Finite-difference time-domain modeling was used to calculate T(incr, max) in six children and two adults exposed to orthogonal plane-wave configurations. We performed a sensitivity study and Monte Carlo analysis to assess the uncertainty of the results. Considering the uncertainties in the model parameters, we found that a peak temperature increase as high as 1 °C can occur for worst-case scenarios at the ICNIRP reference levels. Since the guidelines are deduced from temperature increase, we used T(incr, max) as being a better metric to prevent excessive localized tissue heating instead of localized peak SAR. However, we note that the exposure time should also be considered in future guidelines. Hence, we advise defining limits on T(incr, max) for specified durations of exposure.

  2. Children and adults exposed to electromagnetic fields at the ICNIRP reference levels: theoretical assessment of the induced peak temperature increase

    NASA Astrophysics Data System (ADS)

    Bakker, J. F.; Paulides, M. M.; Neufeld, E.; Christ, A.; Kuster, N.; van Rhoon, G. C.

    2011-08-01

    To avoid potentially adverse health effects of electromagnetic fields (EMF), the International Commission on Non-Ionizing Radiation Protection (ICNIRP) has defined EMF reference levels. Restrictions on induced whole-body-averaged specific absorption rate (SARwb) are provided to keep the whole-body temperature increase (Tbody, incr) under 1 °C during 30 min. Additional restrictions on the peak 10 g spatial-averaged SAR (SAR10g) are provided to prevent excessive localized tissue heating. The objective of this study is to assess the localized peak temperature increase (Tincr, max) in children upon exposure at the reference levels. Finite-difference time-domain modeling was used to calculate Tincr, max in six children and two adults exposed to orthogonal plane-wave configurations. We performed a sensitivity study and Monte Carlo analysis to assess the uncertainty of the results. Considering the uncertainties in the model parameters, we found that a peak temperature increase as high as 1 °C can occur for worst-case scenarios at the ICNIRP reference levels. Since the guidelines are deduced from temperature increase, we used Tincr, max as being a better metric to prevent excessive localized tissue heating instead of localized peak SAR. However, we note that the exposure time should also be considered in future guidelines. Hence, we advise defining limits on Tincr, max for specified durations of exposure.

  3. Children and adults exposed to low-frequency magnetic fields at the ICNIRP reference levels: theoretical assessment of the induced electric fields.

    PubMed

    Bakker, J F; Paulides, M M; Neufeld, E; Christ, A; Chen, X L; Kuster, N; van Rhoon, G C

    2012-04-07

    To avoid potentially adverse health effects, the International Commission on Non-Ionizing Radiation Protection (ICNIRP) has defined reference levels for time varying magnetic fields. Restrictions on the electric fields induced in the human body are provided based on biological response data for peripheral nerve stimulation and the induction of phosphenes. Numerical modeling is commonly used to assess the induced electric fields for various exposure configurations. The objective of this study was to assess the variations of the electric fields induced in children and adults and to compare the exposure at reference levels with the basic restrictions as function of anatomy. We used the scalar potential finite element method to calculate the induced electric fields in six children and two adults when exposed to uniform magnetic fields polarized in three orthogonal directions. We found that the induced electric fields are within the ICNIRP basic restrictions in nearly all cases. In PNS tissues, we found electric fields up to 95% (upper uncertainty limit due to discretization errors, k = 2) of the ICNIRP basic restrictions for exposures at the general public reference levels. For occupational reference levels, we found an over-exposure of maximum 79% (k = 2) in PNS tissues. We further found that the ICNIRP recommendations on spatial averaging in 2 × 2 × 2 mm³ contiguous tissue volumes and removal of peak values by the 99th percentile cause the results to depend strongly on the grid discretization step (i.e. an uncertainty of more than 50% at 2 mm) and the number of distinguished tissues in the anatomical models. The computational results obtained by various research institutes should be robust for different discretization settings and various anatomical models. Therefore, we recommend considering alternative routines for small anatomical structures such as non-contiguous averaging without taking the 99th percentile in future guidelines leading to consistent

  4. Simulation of the temperature elevation in children exposed to plane wave electromagnetic fields (10 MHz-1 GHz) at the ICNIRP reference level.

    PubMed

    Niedermayr, Florian; Leitgeb, Norbert; Siegl, Werner

    2012-05-31

    Because of a lack of thermal models, to date, limitation of exposure to an electromagnetic field (EMF) has been based on restricting intracorporal specific absorption rates. To allow convenient compliance checks, reference field values have been defined. If they are met, compliance with basic restrictions is assumed. This article demonstrates that this assumption is not valid in every case. It has therefore been investigated as to whether the biological goal of limiting tissue heating is still met, in particular with regard to children. The thermal solver applied is based on the bioheat equation, with implemented additional improvements that allow consideration of blood flow and metabolic rate as a function of local tissue temperature rise and, in addition, adapt the blood temperature relative to the absorbed power. As a further improvement, heat exchange at the tissue/air boundary has been modeled, with radiation, convection, and sweating considered as well. The mathematical equations describing these additional thermoregulatory mechanisms were taken from the literature and unified in the thermoregulatory model used for this study. For the investigated case of plane wave exposure, the results confirm the violation of the basic restrictions in five of the six models when exposed to reference EMF levels. However, using thermal modeling, it was possible to demonstrate that heating remained within the biological tolerances. In particular, temperature elevation of the body core temperature remained <0.014°C and the local peak temperature did not exceed 1°C.

  5. Mapping of radio frequency electromagnetic field exposure levels in outdoor environment and comparing with reference levels for general public health.

    PubMed

    Cansiz, Mustafa; Abbasov, Teymuraz; Kurt, M Bahattin; Celik, A Recai

    2016-11-02

    In this study, radio frequency electromagnetic field exposure levels were measured on the main streets in the city center of Diyarbakır, Turkey. Measured electric field levels were plotted on satellite imagery of Diyarbakır and were compared with exposure guidelines published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Exposure measurements were performed in dense urban, urban and suburban areas each day for 7 consecutive days. The measurement system consisted of high precision and portable spectrum analyzer, three-axis electric field antenna, connection cable and a laptop which was used to record the measurement samples as a data logger. The highest exposure levels were detected for two places, which are called Diclekent and Batıkent. It was observed that the highest instantaneous electric field strength value for Batıkent was 7.18 V/m and for Diclekent was 5.81 V/m. It was statistically determined that the main contributor band to the total exposure levels was Universal Mobile Telecommunications System band. Finally, it was concluded that all measured exposure levels were lower than the reference levels recommended by ICNIRP for general public health.Journal of Exposure Science and Environmental Epidemiology advance online publication, 2 November 2016; doi:10.1038/jes.2016.64.

  6. Influence of the surface averaging procedure of the current density in assessing compliance with the ICNIRP low-frequency basic restrictions by means of numerical techniques.

    PubMed

    Zoppetti, N; Andreuccetti, D

    2009-08-07

    Although the calculation of the surface average of the low-frequency current density distribution over a cross-section of 1 cm2 is required by ICNIRP guidelines, no reference averaging algorithm is indicated, neither in the ICNIRP guidelines nor in the Directive 2004/40/EC that is based on them. The lack of a general standard algorithm that fulfils the ICNIRP guidelines' requirements is particularly critical in the prospective of the 2004/40/EC Directive endorsement, since the compliance to normative limits refers to well-defined procedures. In this paper, two case studies are considered, in which the calculation of the surface average is performed using a simplified approach widely used in the literature and an original averaging procedure. This analysis, aimed at quantifying the expected differences and to single out their sources, shows that the choice of the averaging algorithm represents an important source of uncertainty in the application of the guideline requirements.

  7. Radio Hazard Safety Assessment for Marine Ship Transmitters: Measurements Using a New Data Collection Method and Comparison with ICNIRP and ARPANSA Limits

    PubMed Central

    Halgamuge, Malka N.

    2015-01-01

    We investigated the levels of radio frequency electromagnetic fields (RF EMFs) emitted from marine ship transmitters. In this study, we recorded the radio frequency (RF) electric field (EF) levels emitted from transmitters from a marine vessel focusing on the areas normally occupied by crew members and passengers. Previous studies considered radiation hazard safety assessment for marine vessels with a limited number of transmitters, such as very high-frequency (VHF) transceivers, radar and communication transmitters. In our investigation, EF levels from seven radio transmitters were measured, including: VHF, medium frequency/high frequency (MF/HF), satellite communication (Sat-Com C), AISnavigation, radar X-band and radar S-band. Measurements were carried out in a 40 m-long, three-level ship (upper deck, bridge deck and bridge roof) at 12 different locations. We developed a new data-collection protocol and performed it under 11 different scenarios to observe and measure the radiation emissions from all of the transmitters. In total, 528 EF field measurements were collected and averaged over all three levels of the marine ship with RF transmitters: the measured electric fields were the lowest on the upper deck (0.82–0.86 V/m), the highest on the bridge roof (2.15–3.70 V/m) and in between on the bridge deck (0.47–1.15 V/m). The measured EF levels were then assessed for compliance with the occupational and general public reference levels of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) standards. The ICNIRP and the ARPANSA limits for the general public were exceeded on the bridge roof; nevertheless, the occupational limits were respected everywhere. The measured EF levels, hence, complied with the ICNIRP guidelines and the ARPANSA standards. In this paper, we provide a new data collection model for future surveys, which could be conducted with

  8. Radio Hazard Safety Assessment for Marine Ship Transmitters: Measurements Using a New Data Collection Method and Comparison with ICNIRP and ARPANSA Limits.

    PubMed

    Halgamuge, Malka N

    2015-05-19

    We investigated the levels of radio frequency electromagnetic fields (RF EMFs) emitted from marine ship transmitters. In this study, we recorded the radio frequency (RF) electric field (EF) levels emitted from transmitters from a marine vessel focusing on the areas normally occupied by crew members and passengers. Previous studies considered radiation hazard safety assessment for marine vessels with a limited number of transmitters, such as very high-frequency (VHF) transceivers, radar and communication transmitters. In our investigation, EF levels from seven radio transmitters were measured, including: VHF, medium frequency/high frequency (MF/HF), satellite communication (Sat-Com C), AISnavigation, radar X-band and radar S-band. Measurements were carried out in a 40 m-long, three-level ship (upper deck, bridge deck and bridge roof) at 12 different locations. We developed a new data-collection protocol and performed it under 11 different scenarios to observe and measure the radiation emissions from all of the transmitters. In total, 528 EF field measurements were collected and averaged over all three levels of the marine ship with RF transmitters: the measured electric fields were the lowest on the upper deck (0.82-0.86 V/m), the highest on the bridge roof (2.15-3.70 V/m) and in between on the bridge deck (0.47-1.15 V/m). The measured EF levels were then assessed for compliance with the occupational and general public reference levels of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) standards. The ICNIRP and the ARPANSA limits for the general public were exceeded on the bridge roof; nevertheless, the occupational limits were respected everywhere. The measured EF levels, hence, complied with the ICNIRP guidelines and the ARPANSA standards. In this paper, we provide a new data collection model for future surveys, which could be conducted with larger

  9. [Diagnostic reference levels in interventional radiology].

    PubMed

    Vañó Carruana, E; Fernández Soto, J M; Sánchez Casanueva, R M; Ten Morón, J I

    2013-12-01

    This article discusses the diagnostic reference levels for radiation exposure proposed by the International Commission on Radiological Protection (ICRP) to facilitate the application of the optimization criteria in diagnostic imaging and interventional procedures. These levels are normally established as the third quartile of the dose distributions to patients in an ample sample of centers and are supposed to be representative of good practice regarding patient exposure. In determining these levels, it is important to evaluate image quality as well to ensure that it is sufficient for diagnostic purposes. When the values for the dose received by patients are systematically higher or much lower than the reference levels, an investigation should determine whether corrective measures need to be applied. The European and Spanish regulations require the use of these reference values in quality assurance programs. For interventional procedures, the dose area product (or kerma area product) values are usually used as reference values together with the time under fluoroscopy and the total number of images acquired. The most modern imaging devices allow the value of the accumulated dose at the entrance to the patient to be calculated to optimize the distribution of the dose on the skin. The ICRP recommends that the complexity of interventional procedures be taken into account when establishing reference levels. In the future, diagnostic imaging departments will have automatic systems to manage patient dosimetric data; these systems will enable continuous dosage auditing and alerts about individual procedures that might involve doses several times above the reference values. This article also discusses aspects that need to be clarified to take better advantage of the reference levels in interventional procedures.

  10. Exposure estimates based on broadband ELF magnetic field measurements versus the ICNIRP multiple frequency rule.

    PubMed

    Paniagua, Jesús M; Rufo, Montaña; Jiménez, Antonio; Pachón, Fernando T; Carrero, Julián

    2015-02-01

    The evaluation of exposure to extremely low-frequency (ELF) magnetic fields using broadband measurement techniques gives satisfactory results when the field has essentially a single frequency. Nevertheless, magnetic fields are in most cases distorted by harmonic components. This work analyses the harmonic components of the ELF magnetic field in an outdoor urban context and compares the evaluation of the exposure based on broadband measurements with that based on spectral analysis. The multiple frequency rule of the International Commission on Non-ionizing Radiation Protection (ICNIRP) regulatory guidelines was applied. With the 1998 ICNIRP guideline, harmonics dominated the exposure with a 55% contribution. With the 2010 ICNIRP guideline, however, the primary frequency dominated the exposure with a 78% contribution. Values of the exposure based on spectral analysis were significantly higher than those based on broadband measurements. Hence, it is clearly necessary to determine the harmonic components of the ELF magnetic field to assess exposure in urban contexts.

  11. The role of skin conductivity in a low frequency exposure assessment for peripheral nerve tissue according to the ICNIRP 2010 guidelines.

    PubMed

    Schmid, Gernot; Cecil, Stefan; Überbacher, Richard

    2013-07-07

    Based on numerical computations using commercially available finite difference time domain code and a state-of-the art anatomical model of a 5-year old child, the influence of skin conductivity on the induced electric field strength inside the tissue for homogeneous front-to-back magnetic field exposure and homogeneous vertical electric field exposure was computed. Both ungrounded as well as grounded conditions of the body model were considered. For electric field strengths induced inside CNS tissue the impact of skin conductivity was found to be less than 15%. However, the results demonstrated that the use of skin conductivity values as obtainable from the most widely used data base of dielectric tissue properties and recommended by safety standards are not suitable for exposure assessment with respect to peripheral nerve tissue according to the ICNIRP 2010 guidelines in which the use of the induced electric field strengths inside the skin is suggested as a conservative surrogate for peripheral nerve exposure. This is due to the fact that the skin conductivity values derived from these data bases refer to the stratum corneum, the uppermost layer of the skin, which does not contain any nerve or receptor cells to be protected from stimulation effects. Using these skin conductivity values which are approximately a factor 250-500 lower than skin conductivity values used in studies on which the ICNIRP 2010 guidelines are based on, may lead to overestimations of the induced electric field strengths inside the skin by substantially more than a factor of 10. However, reliable conductivity data of deeper skin layers where nerve and preceptor cells are located is very limited. It is therefore recommended to include appropriate background information in the ICNIRP guidelines and the dielectric tissue property databases, and to put some emphasis on a detailed layer-specific characterization of skin conductivity in near future.

  12. Determination of carbon-14 in environmental level, solid reference materials.

    PubMed

    Blowers, Paul; Caborn, Jane; Dell, Tony; Gingell, Terry; Harms, Arvic; Long, Stephanie; Sleep, Darren; Stewart, Charlie; Walker, Jill; Warwick, Phil E

    2011-10-01

    An intercomparison exercise to determine the (14)C activity concentrations in a range of solid, environmental level materials was conducted between laboratories in the UK. IAEA reference materials, C2, C6 and C7, and an in-house laboratory QA material were dispatched in 2006 to ten laboratories comprising of members of the Analyst Informal Working Group (AIWG) and one other invited party. The laboratories performed the determinations using a number of techniques, and using the results each one was evaluated in terms of levels of precision, sensitivity and limits of detection. The results of the study show that all techniques are capable of successfully analysing (14)C in environmental level materials, however, a shortage of certified environmental reference materials exists. The suitability of the IAEA reference materials and other material for use as reference materials was also assessed.

  13. Change in childhood lead exposure prevalence with new reference level.

    PubMed

    Leafe, Morgan; Irigoyen, Matilde; DeLago, Cynthia; Hassan, Amman; Braitman, Leonard

    2015-06-01

    In 2012, the Centers for Disease Control and Prevention changed the "actionable" reference blood lead level from 10 μg/dL to 5 μg/dL, representing the highest 2.5 percentile of lead levels nationwide. In a high-risk urban community, the prevalence of children classified as lead exposed increased ninefold, from 1% to 9.1% (p < .0001) with the new reference level. This dramatic increase in the prevalence of children newly classified as lead exposed will require additional health care and public health resources for tracking, surveillance, and home lead abatement.

  14. Establishment of diagnostic reference levels for dental intraoral radiography.

    PubMed

    Manousaridis, G; Koukorava, C; Hourdakis, C J; Kamenopoulou, V; Yakoumakis, E; Tsiklakis, K

    2013-10-01

    Diagnostic reference levels (DRLs) is a tool for the optimisation of radiological procedures. Establishment of a DRL is a requirement of national regulations. Measurements performed by the Greek Atomic Energy Commission on 529 dental intraoral radiographic facilities have been used in order to define DRLs for digital and film imaging modalities, taking into account the region of the mouth to be imaged. Thus, different DRL values have been proposed for minimum (usually incisors), maximum (usually maxillary molars) and average exposure settings, both for film and digital imaging. The results have been compared with similar studies performed in Europe and the USA and are in line with the most recent ones.

  15. Diagnostic reference level of computed tomography (CT) in Japan.

    PubMed

    Fukushima, Yasuhiro; Tsushima, Yoshito; Takei, Hiroyuki; Taketomi-Takahashi, Ayako; Otake, Hidenori; Endo, Keigo

    2012-08-01

    Optimisation of computed tomography (CT) parameters is important in avoiding excess radiation exposure. The aim of this study is to establish the diagnostic reference levels (DRL) of CT in Japan by using dose-length product (DLP). Datasheets were sent to all hospitals/clinics which had CT scanner(s) in Gunma prefecture. Data were obtained for all patients who underwent CT during a single month (June 2010), and the distributions of DLP were evaluated for eight anatomical regions and five patient age groups. The DRL was defined as the 25th and 75th percentiles of DLP. Datasheets were collected from 80 of 192 hospitals/clinics (26 090 patients). DLP for head CT of paediatric patients tended to be higher in Japan compared with DRLs of paediatric head CTs reported from the EU or Syria. Although this study was performed with limited samples, DLP for adult patients were at comparable levels for all anatomical regions.

  16. Australian diagnostic reference levels for multi detector computed tomography.

    PubMed

    Hayton, Anna; Wallace, Anthony; Marks, Paul; Edmonds, Keith; Tingey, David; Johnston, Peter

    2013-03-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) is undertaking web based surveys to obtain data to establish national diagnostic reference levels (DRLs) for diagnostic imaging. The first set of DRLs to be established are for multi detector computed tomography (MDCT). The survey samples MDCT dosimetry metrics: dose length product (DLP, mGy.cm) and volume computed tomography dose index (CTDIvol, mGy), for six common protocols/habitus: Head, Neck, Chest, AbdoPelvis, ChestAbdoPelvis and Lumbar Spine from individual radiology clinics and platforms. A practice reference level (PRL) for a given platform and protocol is calculated from a compliant survey containing data collected from at least ten patients. The PRL is defined as the median of the DLP/CTDIvol values for a single compliant survey. Australian National DRLs are defined as the 75th percentile of the distribution of the PRLs for each protocol and age group. Australian National DRLs for adult MDCT have been determined in terms of DLP and CTDIvol. In terms of DLP the national DRLs are 1,000 mGy cm, 600 mGy cm, 450 mGy cm, 700 mGy cm, 1,200 mGy cm, and 900 mGy cm for the protocols Head, Neck, Chest, AbdoPelvis, ChestAbdoPelvis and Lumbar Spine respectively. Average dose values obtained from the European survey Dose Datamed I reveal Australian doses to be higher by comparison for four out of the six protocols. The survey is ongoing, allowing practices to optimise dose delivery as well as allowing the periodic update of DRLs to reflect changes in technology and technique.

  17. Low-level lasers and mRNA levels of reference genes used in Escherichia coli

    NASA Astrophysics Data System (ADS)

    Teixeira, A. F.; Machado, Y. L. R. C.; Fonseca, A. S.; Mencalha, A. L.

    2016-11-01

    Low-level lasers are widely used for the treatment of diseases and antimicrobial photodynamic therapy. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) is widely used to evaluate mRNA levels and output data from a target gene are commonly relative to a reference mRNA that cannot vary according to treatment. In this study, the level of reference genes from Escherichia coli exposed to red or infrared lasers at different fluences was evaluated. E. coli AB1157 cultures were exposed to red (660 nm) and infrared (808 nm) lasers, incubated (20 min, 37 °C), the total RNA was extracted, and cDNA synthesis was performed to evaluate mRNA levels from arcA, gyrA and rpoA genes by RT-qPCR. Melting curves and agarose gel electrophoresis were carried out to evaluate specific amplification. Data were analyzed by geNorm, NormFinder and BestKeeper. The melting curve and agarose gel electrophoresis showed specific amplification. Although mRNA levels from arcA, gyrA or rpoA genes presented no significant variations trough a traditional statistical analysis, Excel-based tools revealed that these reference genes are not suitable for E. coli cultures exposed to lasers. Our data showed that exposure to low-level red and infrared lasers at different fluences alter the mRNA levels from arcA, gyrA and rpoA in E. coli cells.

  18. Development of a low-level radon reference atmosphere.

    PubMed

    Linzmaier, Diana; Röttger, Annette

    2013-11-01

    In order to calibrate measurement devices for the activity concentration of Rn-222 (radon) in air below 1,000 Bq/m(3), a constant for long time (>5d), homogeneous reference atmosphere is created by a certified activity in a certified volume. The PTB developed this reference atmosphere from 150 Bq/m(3) to 2,000 Bq/m(3) based on the precisely known emanation of Rn-222 from a Ra-226 activity standard. This set-up reduces uncertainties and increases the range of traceability for commercial radon measurement devices. Thus, a gap in radon metrology is closed. The new primary standard for reference atmospheres is realised with a combined relative standard uncertainty of 1.1%.

  19. Radiometer calibration procedure and beacon attenuation estimation reference level

    NASA Technical Reports Server (NTRS)

    Crane, Robert K.

    1994-01-01

    The primary objectives are to compare radiometer attenuation with beacon attenuation and to compare sky temperature estimates with calculations using simultaneous meteorological data. Secondary objectives are: (1) noise diode and reference load measurements and (2) to adjust for outside temperature and component temperature changes.

  20. Reference commercial high-level waste glass and canister definition.

    SciTech Connect

    Slate, S.C.; Ross, W.A.; Partain, W.L.

    1981-09-01

    This report presents technical data and performance characteristics of a high-level waste glass and canister intended for use in the design of a complete waste encapsulation package suitable for disposal in a geologic repository. The borosilicate glass contained in the stainless steel canister represents the probable type of high-level waste product that will be produced in a commercial nuclear-fuel reprocessing plant. Development history is summarized for high-level liquid waste compositions, waste glass composition and characteristics, and canister design. The decay histories of the fission products and actinides (plus daughters) calculated by the ORIGEN-II code are presented.

  1. Forget the Desk Job: Current Roles and Responsibilities in Entry-Level Reference Job Advertisements

    ERIC Educational Resources Information Center

    Detmering, Robert; Sproles, Claudene

    2012-01-01

    This study examines the evolving roles and responsibilities of entry-level academic reference positions, as stated in recent job advertisements posted on the American Library Association's JobLIST Web site and other sources. Findings from a content analysis of these advertisements indicate that current entry-level reference positions in academic…

  2. FDTD analysis of human body-core temperature elevation due to RF far-field energy prescribed in the ICNIRP guidelines.

    PubMed

    Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu

    2007-08-21

    This study investigated the relationship between the specific absorption rate and temperature elevation in an anatomically-based model named NORMAN for exposure to radio-frequency far fields in the ICNIRP guidelines (1998 Health Phys. 74 494-522). The finite-difference time-domain method is used for analyzing the electromagnetic absorption and temperature elevation in NORMAN. In order to consider the variability of human thermoregulation, parameters for sweating are derived and incorporated into a conventional sweating formula. First, we investigated the effect of blood temperature variation modeling on body-core temperature. The computational results show that the modeling of blood temperature variation was the dominant factor influencing the body-core temperature. This is because the temperature in the inner tissues is elevated via the circulation of blood whose temperature was elevated due to EM absorption. Even at different frequencies, the body-core temperature elevation at an identical whole-body average specific absorption rate (SAR) was almost the same, suggesting the effectiveness of the whole-body average SAR as a measure in the ICNIRP guidelines. Next, we discussed the effect of sweating on the temperature elevation and thermal time constant of blood. The variability of temperature elevation caused by the sweating rate was found to be 30%. The blood temperature elevation at the basic restriction in the ICNIRP guidelines of 0.4 W kg(-1) is 0.25 degrees C even for a low sweating rate. The thermal time constant of blood temperature elevation was 23 min and 52 min for a man with a lower and a higher sweating rate, respectively, which is longer than the average time of the SAR in the ICNIRP guidelines. Thus, the whole-body average SAR required for blood temperature elevation of 1 degrees C was 4.5 W kg(-1) in the model of a human with the lower sweating coefficients for 60 min exposure. From a comparison of this value with the basic restriction in the ICNIRP

  3. Hearing Tests on Mobile Devices: Evaluation of the Reference Sound Level by Means of Biological Calibration

    PubMed Central

    Kipiński, Lech; Grysiński, Tomasz; Kręcicki, Tomasz

    2016-01-01

    Background Hearing tests carried out in home setting by means of mobile devices require previous calibration of the reference sound level. Mobile devices with bundled headphones create a possibility of applying the predefined level for a particular model as an alternative to calibrating each device separately. Objective The objective of this study was to determine the reference sound level for sets composed of a mobile device and bundled headphones. Methods Reference sound levels for Android-based mobile devices were determined using an open access mobile phone app by means of biological calibration, that is, in relation to the normal-hearing threshold. The examinations were conducted in 2 groups: an uncontrolled and a controlled one. In the uncontrolled group, the fully automated self-measurements were carried out in home conditions by 18- to 35-year-old subjects, without prior hearing problems, recruited online. Calibration was conducted as a preliminary step in preparation for further examination. In the controlled group, audiologist-assisted examinations were performed in a sound booth, on normal-hearing subjects verified through pure-tone audiometry, recruited offline from among the workers and patients of the clinic. In both the groups, the reference sound levels were determined on a subject’s mobile device using the Bekesy audiometry. The reference sound levels were compared between the groups. Intramodel and intermodel analyses were carried out as well. Results In the uncontrolled group, 8988 calibrations were conducted on 8620 different devices representing 2040 models. In the controlled group, 158 calibrations (test and retest) were conducted on 79 devices representing 50 models. Result analysis was performed for 10 most frequently used models in both the groups. The difference in reference sound levels between uncontrolled and controlled groups was 1.50 dB (SD 4.42). The mean SD of the reference sound level determined for devices within the same model

  4. Levelized Cost of Energy Analysis of Marine and Hydrokinetic Reference Models: Preprint

    SciTech Connect

    Jenne, D. S.; Yu, Y. H.; Neary, V.

    2015-04-24

    In 2010 the U.S. Department of Energy initiated the development of six marine energy converter reference models. The reference models are point designs of well-known marine energy converters. Each device was designed to operate in a specific marine resource, instead of a generic device that can be deployed at any location. This method allows each device to be used as a benchmark for future reference model to benchmark future devices. The six designs consist of three current energy converters and three wave energy converters. The reference model project has generated both technical and economic data sets that are available in the public domain. The methodology to calculate the levelized cost of energy for the reference model project and an overall comparison of the cost of energy from these six reference-model designs are presented in this paper.

  5. Determination of safety distance limits for a human near a cellular base station antenna, adopting the IEEE standard or ICNIRP guidelines.

    PubMed

    Cooper, Justin; Marx, Bernd; Buhl, Johannes; Hombach, Volker

    2002-09-01

    This paper investigates the minimum distance for a human body in the near field of a cellular telephone base station antenna for which there is compliance with the IEEE or ICNIRP threshold values for radio frequency electromagnetic energy absorption in the human body. First, local maximum specific absorption rates (SARs), measured and averaged over volumes equivalent to 1 and to 10 g tissue within the trunk region of a physical, liquid filled shell phantom facing and irradiated by a typical GSM 900 base station antenna, were compared to corresponding calculated SAR values. The calculation used a homogeneous Visible Human body model in front of a simulated base station antenna of the same type. Both real and simulated base station antennas operated at 935 MHz. Antenna-body distances were between 1 and 65 cm. The agreement between measurements and calculations was excellent. This gave confidence in the subsequent calculated SAR values for the heterogeneous Visible Human model, for which each tissue was assigned the currently accepted values for permittivity and conductivity at 935 MHz. Calculated SAR values within the trunk of the body were found to be about double those for the homogeneous case. When the IEEE standard and the ICNIRP guidelines are both to be complied with, the local SAR averaged over 1 g tissue was found to be the determining parameter. Emitted power values from the antenna that produced the maximum SAR value over 1 g specified in the IEEE standard at the base station are less than those needed to reach the ICNIRP threshold specified for the local SAR averaged over 10 g. For the GSM base station antenna investigated here operating at 935 MHz with 40 W emitted power, the model indicates that the human body should not be closer to the antenna than 18 cm for controlled environment exposure, or about 95 cm for uncontrolled environment exposure. These safe distance limits are for SARs averaged over 1 g tissue. The corresponding safety distance limits

  6. Defining Top-of-Atmosphere Flux Reference Level for Earth Radiation Budget Studies

    NASA Technical Reports Server (NTRS)

    Loeb, N. G.; Kato, S.; Wielicki, B. A.

    2002-01-01

    To estimate the earth's radiation budget at the top of the atmosphere (TOA) from satellite-measured radiances, it is necessary to account for the finite geometry of the earth and recognize that the earth is a solid body surrounded by a translucent atmosphere of finite thickness that attenuates solar radiation differently at different heights. As a result, in order to account for all of the reflected solar and emitted thermal radiation from the planet by direct integration of satellite-measured radiances, the measurement viewing geometry must be defined at a reference level well above the earth s surface (e.g., 100 km). This ensures that all radiation contributions, including radiation escaping the planet along slant paths above the earth s tangent point, are accounted for. By using a field-of- view (FOV) reference level that is too low (such as the surface reference level), TOA fluxes for most scene types are systematically underestimated by 1-2 W/sq m. In addition, since TOA flux represents a flow of radiant energy per unit area, and varies with distance from the earth according to the inverse-square law, a reference level is also needed to define satellite-based TOA fluxes. From theoretical radiative transfer calculations using a model that accounts for spherical geometry, the optimal reference level for defining TOA fluxes in radiation budget studies for the earth is estimated to be approximately 20 km. At this reference level, there is no need to explicitly account for horizontal transmission of solar radiation through the atmosphere in the earth radiation budget calculation. In this context, therefore, the 20-km reference level corresponds to the effective radiative top of atmosphere for the planet. Although the optimal flux reference level depends slightly on scene type due to differences in effective transmission of solar radiation with cloud height, the difference in flux caused by neglecting the scene-type dependence is less than 0.1%. If an inappropriate

  7. Does the Choice of Reference Levels of Education Matter in the ORU Earnings Equation?

    ERIC Educational Resources Information Center

    Chiswick, Barry R.; Miller, Paul W.

    2010-01-01

    This paper examines whether the results of the earnings equation developed in the over-education/required education/under-education (ORU) literature are sensitive to whether the usual or reference levels of education are measured using the Realized Matches or Worker Self-Assessment methods. The analyses are conducted for all male native-born and…

  8. Nature of Environmental Education in Bangladesh: A School Level Assessment with Reference to the National Curriculum

    ERIC Educational Resources Information Center

    Chowdhury, M. A. Taiyeb

    2014-01-01

    This paper attempts to identify the nature of formal environmental education in Bangladesh at school level with particular reference to the national curriculum. The main objective of the study is to assess the contents of the school textbooks for each standard, and to see whether the diversified themes covered are a good representation of…

  9. Reference dose levels for patients undergoing common diagnostic X-ray examinations in Irish hospitals.

    PubMed

    Johnston, D A; Brennan, P C

    2000-04-01

    Wide variations in patient dose for the same type of X-ray examination have been evident from various international dose surveys. Reference dose levels provide a framework to reduce this variability and aid in the optimization of radiation protection. The aim of this study was to establish, for the first time, a baseline for national reference dose levels in Ireland for four of the most common X-ray examinations: chest, abdomen, pelvis and lumbar spine. Measurements of entrance surface dose using thermoluminescent dosemeters (TLDs) for these four X-ray examinations were performed on 10 patients in each of 16 randomly selected hospitals. This represented 42% of Irish hospitals applicable to this study. Results have shown wide variation of mean hospital doses, from a factor of 3 for an anteroposterior lumbar spine to a factor of 23 for the chest X-ray. The difference between maximum and minimum individual patient dose values varied up to a factor of 75. Reasons for these dose variations were complex but, in general, low tube potential, high mAs and low filtration were associated with high-dose hospitals. This study also demonstrated lower reference dose levels of up to 40% when compared with those established by the UK and the Commission of the European Communities for four out of six projections. Only the chest X-ray exhibited a similar reference level to those established elsewhere. This emphasizes the importance of each country establishing its own reference dose levels that are appropriate to their own radiographic techniques and practices in order to optimize patient protection.

  10. Measurement of the weighted peak level for occupational exposure to gradient magnetic fields for 1.5 and 3 Tesla MRI body scanners.

    PubMed

    Bonutti, F; Tecchio, M; Maieron, M; Trevisan, D; Negro, C; Calligaris, F

    2016-03-01

    The purpose of this work is to give a contribution to the construction of a comprehensive knowledge of the exposure levels to gradient magnetic fields (GMF) in terms of the weighed peak (WP), especially for 3 Tesla scanners for which there are still few works available in the literature. A new generation probe for the measurement of electromagnetic fields in the range of 1 Hz-400 kHz was used to assess the occupational exposure levels to the GMF for 1.5 and 3.0 Tesla MRI body scanners, using the method of the WP according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) approach. The probe was placed at a height of 1.1 m, close to the MRI scanners, where operators could stay during some medical procedures with particular issues. The measurements were performed for a set of typical acquisition sequences for body (liver) and head exams. The measured values of WP were in compliance with ICNIRP 2010 reference levels for occupational exposures.

  11. Nitric oxide levels regulate the immune response of Drosophila melanogaster reference laboratory strains to bacterial infections.

    PubMed

    Eleftherianos, Ioannis; More, Kareen; Spivack, Stephanie; Paulin, Ethan; Khojandi, Arman; Shukla, Sajala

    2014-10-01

    Studies on the innate immune response against microbial infections in Drosophila melanogaster involve mutant strains and their reference strains that act as experimental controls. We used five standard D. melanogaster laboratory reference strains (Oregon R, w1118, Canton-S, Cinnabar Brown, and Yellow White [YW]) and investigated their response against two pathogenic bacteria (Photorhabdus luminescens and Enterococcus faecalis) and two nonpathogenic bacteria (Escherichia coli and Micrococcus luteus). We detected high sensitivity among YW flies to bacterial infections and increased bacterial growth compared to the other strains. We also found variation in the transcription of certain antimicrobial peptide genes among strains, with Oregon and YW infected flies showing the highest and lowest gene transcription levels in most cases. We show that Oregon and w1118 flies possess more circulating hemocytes and higher levels of phenoloxidase activity than the other strains upon infection with the nonpathogenic bacteria. We further observed reduced fat accumulation in YW flies infected with the pathogenic bacteria, which suggests a possible decline in physiological condition. Finally, we found that nitrite levels are significantly lower in infected and uninfected YW flies compared to w1118 flies and that nitric oxide synthase mutant flies in YW background are more susceptible to bacterial infection compared to mutants in w1118 background. Therefore, increased sensitivity of YW flies to bacterial infections can be partly attributed to lower levels of nitric oxide. Such studies will significantly contribute toward a better understanding of the genetic variation between D. melanogaster reference strains.

  12. Nitric Oxide Levels Regulate the Immune Response of Drosophila melanogaster Reference Laboratory Strains to Bacterial Infections

    PubMed Central

    More, Kareen; Spivack, Stephanie; Paulin, Ethan; Khojandi, Arman; Shukla, Sajala

    2014-01-01

    Studies on the innate immune response against microbial infections in Drosophila melanogaster involve mutant strains and their reference strains that act as experimental controls. We used five standard D. melanogaster laboratory reference strains (Oregon R, w1118, Canton-S, Cinnabar Brown, and Yellow White [YW]) and investigated their response against two pathogenic bacteria (Photorhabdus luminescens and Enterococcus faecalis) and two nonpathogenic bacteria (Escherichia coli and Micrococcus luteus). We detected high sensitivity among YW flies to bacterial infections and increased bacterial growth compared to the other strains. We also found variation in the transcription of certain antimicrobial peptide genes among strains, with Oregon and YW infected flies showing the highest and lowest gene transcription levels in most cases. We show that Oregon and w1118 flies possess more circulating hemocytes and higher levels of phenoloxidase activity than the other strains upon infection with the nonpathogenic bacteria. We further observed reduced fat accumulation in YW flies infected with the pathogenic bacteria, which suggests a possible decline in physiological condition. Finally, we found that nitrite levels are significantly lower in infected and uninfected YW flies compared to w1118 flies and that nitric oxide synthase mutant flies in YW background are more susceptible to bacterial infection compared to mutants in w1118 background. Therefore, increased sensitivity of YW flies to bacterial infections can be partly attributed to lower levels of nitric oxide. Such studies will significantly contribute toward a better understanding of the genetic variation between D. melanogaster reference strains. PMID:25047850

  13. Mean glandular dose in six digital mammography services in Santiago, Chile: preliminary reference levels.

    PubMed

    Leyton, Fernando; Nogueira, Maria Do Socorro; Dantas, Marcelino; Duran, Maria Paz; Ubeda, Carlos

    2015-07-01

    The purpose of this paper was to estimate mean glandular dose levels (DG) in six digital mammography systems in Santiago, Chile, and to propose preliminary reference levels to execute mammography in Chile. The study was carried out assessing two direct digital systems and four computer-based radiography (CR) systems. Estimates of DG were calculated for different thicknesses of polymethyl methacrylate according to the quality control protocol in digital mammography of the Spanish Society of Medical Physics and NHSBSP Equipment Report 0604 Version 3. DG values ranged between 0.64 and 7.26 mGy for a range of 20- to 70-mm thickness, respectively. Thirty-six per cent of DG was higher than the acceptable dose level and 100 % of DG was higher than the desirable level. It is therefore necessary to optimise doses. The initial proposal to establish dose reference levels for DG would range between 0.90 and 6.40 mGy for a thickness range of 20 to 70 mm.

  14. Age-specific reference values for serum FSH and estradiol levels throughout the reproductive period.

    PubMed

    Grisendi, Valentina; Spada, Elena; Argento, Cindy; Plebani, Maddalena; Milani, Silvano; Seracchioli, Renato; Volpe, Annibale; La Marca, Antonio

    2014-06-01

    High serum day 3 FSH levels are associated with poor ovarian reserve and reduced fertility, but the interpretation of FSH values according to age is still not univocal. The purpose of this study was to determine age-dependent reference values in women with regular menstrual cycles and FSH as a guide for specialists. The study was performed at the Department of Mother-Infant of a University-based tertiary care centre. One-hundred ninety-two healthy normal menstruating women were recruited for the study. All patients attended the department on menstrual cycle day 3 for a blood sample for FSH and estradiol determination. A linear relationship between FSH or estradiol serum levels and age was observed. The FSH level increased by 0.11 IU for every year of age (1 IU for every 9 years of age). The values of FSH and estradiol corresponding to the 5th, 25th, 50th, 75th, 95th centiles for any specific age have been calculated. Serum FSH levels need to be interpreted according to age-dependent reference values. Serum FSH levels on 95th centile for any age may represent a warning sign for reduced ovarian reserve.

  15. Reference design and operations for deep borehole disposal of high-level radioactive waste.

    SciTech Connect

    Herrick, Courtney Grant; Brady, Patrick Vane; Pye, Steven; Arnold, Bill Walter; Finger, John Travis; Bauer, Stephen J.

    2011-10-01

    A reference design and operational procedures for the disposal of high-level radioactive waste in deep boreholes have been developed and documented. The design and operations are feasible with currently available technology and meet existing safety and anticipated regulatory requirements. Objectives of the reference design include providing a baseline for more detailed technical analyses of system performance and serving as a basis for comparing design alternatives. Numerous factors suggest that deep borehole disposal of high-level radioactive waste is inherently safe. Several lines of evidence indicate that groundwater at depths of several kilometers in continental crystalline basement rocks has long residence times and low velocity. High salinity fluids have limited potential for vertical flow because of density stratification and prevent colloidal transport of radionuclides. Geochemically reducing conditions in the deep subsurface limit the solubility and enhance the retardation of key radionuclides. A non-technical advantage that the deep borehole concept may offer over a repository concept is that of facilitating incremental construction and loading at multiple perhaps regional locations. The disposal borehole would be drilled to a depth of 5,000 m using a telescoping design and would be logged and tested prior to waste emplacement. Waste canisters would be constructed of carbon steel, sealed by welds, and connected into canister strings with high-strength connections. Waste canister strings of about 200 m length would be emplaced in the lower 2,000 m of the fully cased borehole and be separated by bridge and cement plugs. Sealing of the upper part of the borehole would be done with a series of compacted bentonite seals, cement plugs, cement seals, cement plus crushed rock backfill, and bridge plugs. Elements of the reference design meet technical requirements defined in the study. Testing and operational safety assurance requirements are also defined. Overall

  16. Establishment of diagnostic reference levels in computed tomography for select procedures in Pudhuchery, India.

    PubMed

    Saravanakumar, A; Vaideki, K; Govindarajan, K N; Jayakumar, S

    2014-01-01

    Computed tomography (CT) scanner under operating conditions has become a major source of human exposure to diagnostic X-rays. In this context, weighed CT dose index (CTDIw), volumetric CT dose index (CTDIv), and dose length product (DLP) are important parameter to assess procedures in CT imaging as surrogate dose quantities for patient dose optimization. The current work aims to estimate the existing dose level of CT scanner for head, chest, and abdomen procedures in Pudhuchery in south India and establish dose reference level (DRL) for the region. The study was carried out for six CT scanners in six different radiology departments using 100 mm long pencil ionization chamber and polymethylmethacrylate (PMMA) phantom. From each CT scanner, data pertaining to patient and machine details were collected for 50 head, 50 chest, and 50 abdomen procedures performed over a period of 1 year. The experimental work was carried out using the machine operating parameters used during the procedures. Initially, dose received in the phantom at the center and periphery was measured by five point method. Using these values CTDIw, CTDIv, and DLP were calculated. The DRL is established based on the third quartile value of CTDIv and DLP which is 32 mGy and 925 mGy.cm for head, 12 mGy and 456 mGy.cm for chest, and 16 mGy and 482 mGy.cm for abdomen procedures. These values are well below European Commission Dose Reference Level (EC DRL) and comparable with the third quartile value reported for Tamil Nadu region in India. The present study is the first of its kind to determine the DRL for scanners operating in the Pudhuchery region. Similar studies in other regions of India are necessary in order to establish a National Dose Reference Level.

  17. Establishment of diagnostic reference levels in computed tomography for select procedures in Pudhuchery, India

    PubMed Central

    Saravanakumar, A.; Vaideki, K.; Govindarajan, K. N.; Jayakumar, S.

    2014-01-01

    Computed tomography (CT) scanner under operating conditions has become a major source of human exposure to diagnostic X-rays. In this context, weighed CT dose index (CTDIw), volumetric CT dose index (CTDIv), and dose length product (DLP) are important parameter to assess procedures in CT imaging as surrogate dose quantities for patient dose optimization. The current work aims to estimate the existing dose level of CT scanner for head, chest, and abdomen procedures in Pudhuchery in south India and establish dose reference level (DRL) for the region. The study was carried out for six CT scanners in six different radiology departments using 100 mm long pencil ionization chamber and polymethylmethacrylate (PMMA) phantom. From each CT scanner, data pertaining to patient and machine details were collected for 50 head, 50 chest, and 50 abdomen procedures performed over a period of 1 year. The experimental work was carried out using the machine operating parameters used during the procedures. Initially, dose received in the phantom at the center and periphery was measured by five point method. Using these values CTDIw, CTDIv, and DLP were calculated. The DRL is established based on the third quartile value of CTDIv and DLP which is 32 mGy and 925 mGy.cm for head, 12 mGy and 456 mGy.cm for chest, and 16 mGy and 482 mGy.cm for abdomen procedures. These values are well below European Commission Dose Reference Level (EC DRL) and comparable with the third quartile value reported for Tamil Nadu region in India. The present study is the first of its kind to determine the DRL for scanners operating in the Pudhuchery region. Similar studies in other regions of India are necessary in order to establish a National Dose Reference Level. PMID:24600173

  18. Determination of pediatric reference levels of FT3, FT4 and TSH measured with ECLusys kits.

    PubMed

    Iwaku, Kenji; Noh, Jaeduk Yoshimura; Minagawa, Akinobu; Kosuga, Yuka; Suzuki, Miho; Sekiya, Kenichi; Matsumoto, Masako; Ohye, Hidemi; Kunii, Yo; Yoshihara, Ai; Watanabe, Natsuko; Mukasa, Koji; Ito, Koichi; Ito, Kunihiko

    2013-01-01

    Reference ranges for serum thyroid hormones free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) in children were set using the assay kits currently used in clinical settings. A total of 342 children (111 males and 231 females) who were negative for antithyroid antibodies (TgAb, TPOAb) and were found to have no abnormalities on ultrasonographic examination of the thyroid gland were divided into 6 age groups: 4-6 years (45 children), 7-8 years (40), 9-10 years (53), 11-12 years (65), 13-14 years (83), and 15 years (56) for the study. FT3, FT4 and TSH levels were determined by electrochemiluminescence immunoassay (ECLIA) (ECLusys FT3, FT4 and TSH).The reference range for FT3 (pg/mL) was 2.91-4.70 for the age group of 4-6 years, 3.10-5.10 for the age group of 7-8 years, 3.10-4.87 for the age group of 9-10 years, 2.78-4.90 for the age group of 11-12 years, 2.77-4.59 for the age group of 13-14 years, and 2.50-4.64 for the age group of 15 years . The reference range for FT4 (ng/dL) was 1.12-1.67, 1.07-1.61, 0.96-1.60, 1.02-1.52, 0.96-1.52, 0.95-1.53. The reference range for TSH (μU/mL) was 0.62-4.90, 0.53-5.16, 0.67-4.52, 0.62-3.36, 0.54-2.78, 0.32-3.00. Serum FT3, FT4 and TSH levels in children differ from those in adults. It is, therefore, of importance to perform evaluation of thyroid function in children using reference values appropriate for the chronological ages, because misdiagnosis of hypothyroidism or inappropriate secretion of TSH (SITSH) and oversight of mild subclinical hypothyroidism could occur if the diagnosis is made using reference values for adults.

  19. Serum thyroglobulin antibody levels within or near to the reference range may interfere with thyroglobulin measurement.

    PubMed

    Locsei, Zoltán; Szabolcs, István; Rácz, Károly; Kovács, Gábor L; Horváth, Dóra; Toldy, Erzsébet

    2012-01-01

    High concentration of thyroglobulin antibodies (TgAb) is a major limiting factor of thyroglobulin measurements in patients with differentiated thyroid cancer. We investigated whether thyroglobulin antibody added to serum samples could interfere with the thyroglobulin assay. Thyroglobulin levels in serum samples with different concentrations of thyroglobulin were measured by electrochemiluminescence immunoassay before and after the addition of increasing concentrations of thyroglobulin antibody using the secondary calibrator solution of the thyroglobulin assay kit containing sheep thyroglobulin antibody to reach thyroglobulin antibody levels within or near to the reference range. Thyroglobulin and thyroglobulin antibody concentrations were also measured in 134 serum samples from 27 patients after thyroid ablation. There was a strong negative association (slope = -1.179) between thyroglobulin antibody and thyroglobulin concentrations in samples with added thyroglobulin antibody (beta = -0.86; P <0.001). Changes in thyroglobulin concentrations were described mathematically as loss of thyroglobulin% = -0.2408 x Ln(thyroglobulin antibody IU/ml) + 0.1944. Thyroglobulin concentrations were significantly lower than those calculated from experiments with added thyroglobulin antibody in 26/134 samples from patients after thyroid ablation. We conclude that if the same TgAb interference exists in the presence of naturally occurring human TgAb, our observation may prove to be useful during follow-up of patients with differentiated thyroid cancer. However, further studies are needed to explore the clinical relevance of thyroglobulin antibody levels within or near to the reference range in monitoring these patients.

  20. A CONCEPTUAL FRAMEWORK FOR MANAGING RADIATION DOSE TO PATIENTS IN DIAGNOSTIC RADIOLOGY USING REFERENCE DOSE LEVELS.

    PubMed

    Almén, Anja; Båth, Magnus

    2016-06-01

    The overall aim of the present work was to develop a conceptual framework for managing radiation dose in diagnostic radiology with the intention to support optimisation. An optimisation process was first derived. The framework for managing radiation dose, based on the derived optimisation process, was then outlined. The outset of the optimisation process is four stages: providing equipment, establishing methodology, performing examinations and ensuring quality. The optimisation process comprises a series of activities and actions at these stages. The current system of diagnostic reference levels is an activity in the last stage, ensuring quality. The system becomes a reactive activity only to a certain extent engaging the core activity in the radiology department, performing examinations. Three reference dose levels-possible, expected and established-were assigned to the three stages in the optimisation process, excluding ensuring quality. A reasonably achievable dose range is also derived, indicating an acceptable deviation from the established dose level. A reasonable radiation dose for a single patient is within this range. The suggested framework for managing radiation dose should be regarded as one part of the optimisation process. The optimisation process constitutes a variety of complementary activities, where managing radiation dose is only one part. This emphasises the need to take a holistic approach integrating the optimisation process in different clinical activities.

  1. Technology, Safety and Costs of Decommissioning a Reference Low-Level Waste Burial Ground. Appendices

    SciTech Connect

    1980-06-01

    Safety and cost information are developed for the conceptual decommissioning of commercial low-level waste (LLW) burial grounds. Two generic burial grounds, one located on an arid western site and the other located on a humid eastern site, are used as reference facilities for the study. The two burial grounds are assumed to have the same site capacity for waste, the same radioactive waste inventory, and similar trench characteristics and operating procedures. The climate, geology. and hydrology of the two sites are chosen to be typical of real western and eastern sites. Volume 2 (Appendices) contains the detailed analyses and data needed to support the results given in Volume 1.

  2. Technology, Safety and Costs of Decommissioning a Reference Low-Level Waste Burial Ground. Main Report

    SciTech Connect

    Murphy, E. S.; Holter, G. M.

    1980-06-01

    Safety and cost information are developed for the conceptual decommissioning of commercial low-level waste (LLW) burial grounds. Two generic burial grounds, one located on an arid western site and the other located on a humid eastern site, are used as reference facilities for the study. The two burial grounds are assumed to have the same site capacity for waste, the same radioactive waste inventory, and similar trench characteristics and operating procedures. The climate, geology. and hydrology of the two sites are chosen to be typical of real western and eastern sites. Volume 1 (Main Report) contains background information and study results in summary form.

  3. Assessment of potential risk levels associated with U.S. Environmental Protection Agency reference values.

    PubMed Central

    Castorina, Rosemary; Woodruff, Tracey J

    2003-01-01

    The U.S. Environmental Protection Agency (U.S. EPA) generally uses reference doses (RfDs) or reference concentrations (RfCs) to assess risks from exposure to toxic substances for noncancer health end points. RfDs and RfCs are supposed to represent lifetime inhalation or ingestion exposure with minimal appreciable risk, but they do not include information about the estimated risk from exposures equal to the RfD/RfC. We used results from benchmark dose modeling approaches recently adopted for use in developing RfDs/RfCs to estimate the risk levels associated with exposures at the RfD/RfC. We searched the U.S. EPA Integrated Risk Information System (IRIS) database and identified 11 chemicals with oral RfDs and 12 chemicals with inhalation RfCs that used benchmark dose modeling. For assessments with sufficient model information, we found that 16 of 21 (76%) of the dose-response models were linear or supralinear. We estimated the risk from exposures at the established RfDs and RfCs for these chemicals using a linear dose-response curve to characterize risk below the observed data. Risk estimates ranged from 1 in 10,000 to 5 in 1,000 for exposures at the RfDs, and from 1 in 10,000 to 3 in 1,000 for exposures at the RfCs. Risk estimates for exposures at the RfD/RfC values derived from sublinear dose-response curves ranged from 3 in 1,000,000,000 to 8 in 10,000. Twenty-four percent of reference values corresponded to estimated risk levels greater than 1 in 1,000; 10 of 14 assessments had points of departure greater than the no-observed-adverse-effect levels. For policy development regarding management of cancer risks, the U.S. EPA often uses 1 in 1,000,000 as a de minimis risk level. Although noncancer outcomes may in some instances be reversible and considered less severe than cancer, our findings call into question the assumption that established RfD and RfC values represent negligibly small risk levels. PMID:12896853

  4. French diagnostic reference levels in diagnostic radiology, computed tomography and nuclear medicine: 2004-2008 review.

    PubMed

    Roch, P; Aubert, B

    2013-04-01

    After 5 y of collecting data on diagnostic reference levels (DRLs), the Nuclear Safety and Radiation Protection French Institute (IRSN) presents the analyses of this data. The analyses of the collected data for radiology, computed tomography (CT) and nuclear medicine allow IRSN to estimate the level of regulatory application by health professionals and the representativeness of current DRL in terms of relevant examinations, dosimetric quantities, numerical values and patient morphologies. Since 2004, the involvement of professionals has highly increased, especially in nuclear medicine, followed by CT and then by radiology. Analyses show some discordance between regulatory examinations and clinical practice. Some of the dosimetric quantities used for the DRL setting are insufficient or not relevant enough, and some numerical values should also be reviewed. On the basis of these findings, IRSN formulates recommendations to update regulatory DRL with current and relevant examination lists, dosimetric quantities and numerical values.

  5. Establishment of multi-slice computed tomography (MSCT) reference level in Johor, Malaysia

    NASA Astrophysics Data System (ADS)

    Karim, M. K. A.; Hashim, S.; Bakar, K. A.; Muhammad, H.; Sabarudin, A.; Ang, W. C.; Bahruddin, N. A.

    2016-03-01

    Radiation doses from computed tomography (CT) are the highest and most hazardous compared to other imaging modalities. This study aimed to evaluate radiation dose in Johor, Malaysia to patients during computed tomography examinations of the brain, chest and abdomen and to establish the local diagnostic reference levels (DRLs) as are present with the current, state- of-art, multi-slice CT scanners. Survey forms were sent to five centres performing CT to obtain data regarding acquisition parameters as well as the dose information from CT consoles. CT- EXPO (Version 2.3.1, Germany) was used to validate the dose information. The proposed DRLs were indicated by rounding the third quartiles of whole dose distributions where mean values of CTDIw (mGy), CTDIvol (mGy) and DLP (mGy.cm) were comparable with other reference levels; 63, 63, and 1015 respectively for CT Brain; 15, 14, and 450 respectively for CT thorax and 16, 17, and 590 respectively for CT abdomen. The study revealed that the CT practice and dose output were revolutionised, and must keep up with the pace of introductory technology. We suggest that CTDIvol should be included in current national DRLs, as modern CTs are configured with a higher number of detectors and are independent of pitch factors.

  6. National diagnostic reference level initiative for computed tomography examinations in Kenya

    PubMed Central

    Korir, Geoffrey K.; Wambani, Jeska S.; Korir, Ian K.; Tries, Mark A.; Boen, Patrick K.

    2016-01-01

    The purpose of this study was to estimate the computed tomography (CT) examination frequency, patient radiation exposure, effective doses and national diagnostic reference levels (NDRLs) associated with CT examinations in clinical practice. A structured questionnaire-type form was developed for recording examination frequency, scanning protocols and patient radiation exposure during CT procedures in fully equipped medical facilities across the country. The national annual number of CT examinations per 1000 people was estimated to be 3 procedures. The volume-weighted CT dose index, dose length product, effective dose and NDRLs were determined for 20 types of adult and paediatric CT examinations. Additionally, the CT annual collective effective dose and effective dose per capita were approximated. The radiation exposure during CT examinations was broadly distributed between the facilities that took part in the study. This calls for a need to develop and implement diagnostic reference levels as a standardisation and optimisation tool for the radiological protection of patients at all the CT facilities nationwide. PMID:25790825

  7. Indication-based national diagnostic reference levels for paediatric CT: a new approach with proposed values.

    PubMed

    Järvinen, H; Seuri, R; Kortesniemi, M; Lajunen, A; Hallinen, E; Savikurki-Heikkilä, P; Laarne, P; Perhomaa, M; Tyrväinen, E

    2015-07-01

    Indication-based national diagnostic reference levels (DRLs) for a few most common paediatric computed tomography (CT) examinations are proposed. Patient dose data (CTDI vol and dose length product) were collected for over 1000 patients in 4 university hospitals with best experiences in paediatric CT. Four indications for chest CT and two for abdomen (abdomen + pelvis), chest + abdomen and head CT were considered. The DRLs for the body examinations are proposed as exponential DRL-curves, where CTDI vol and dose length product are presented as a function of patient weight. The same DRL curve applies to all the indications studied. The basic 75 % level curve is supplemented by 50 % level curve to enable considerations on varying levels of technology. For head CT, DRLs are proposed for a few age groups (1, 1-5, 5-10 and 10-15 y), separately for routine CT and CT for ventricular size. The proposed DRLs are generally lower than the few published DRLs in other countries.

  8. Reference ranges and determinants of total hCG levels during pregnancy: the Generation R Study.

    PubMed

    Korevaar, Tim I M; Steegers, Eric A P; de Rijke, Yolanda B; Schalekamp-Timmermans, Sarah; Visser, W Edward; Hofman, Albert; Jaddoe, Vincent W V; Tiemeier, Henning; Visser, Theo J; Medici, Marco; Peeters, Robin P

    2015-09-01

    Human chorionic gonadotropin (hCG) is a pregnancy hormone secreted by the placental synctiotrophoblast cell layer that has been linked to fetal growth and various placental, uterine and fetal functions. In order to investigate the effects of hCG on clinical endpoints, knowledge on reference range (RR) methodology and determinants of gestational hCG levels is crucial. Moreover, a better understanding of gestational hCG physiology can improve current screening programs and future clinical management. Serum total hCG levels were determined in 8195 women participating in the Generation R Study. Gestational age specific RRs using 'ultrasound derived gestational age' (US RRs) were calculated and compared with 'last menstrual period derived gestational age' (LMP RRs) and a model-based RR. We also investigated which pregnancy characteristics were associated with hCG levels. Compared to the US RRs, the LMP RRs were lower, most notably for the median and lower limit levels. No considerable differences were found between RRs calculated in the general population or in uncomplicated pregnancies only. Maternal smoking, BMI, parity, ethnicity, fetal gender, placental weight and hyperemesis gravidarum symptoms were associated with total hCG. We provide gestational RRs for total hCG and show that total hCG values and RR cut-offs during pregnancy vary depending on pregnancy dating methodology. This is likely due to the influence of hCG on embryonic growth, suggesting that ultrasound based pregnancy dating might be less reliable in women with high/low hCG levels. Furthermore, we identify different pregnancy characteristics that influence total hCG levels considerably and should therefore be accounted for in clinical studies.

  9. Low-level radioactive waste technology: a selected, annotated bibliography. [416 references

    SciTech Connect

    Fore, C.S.; Carrier, R.F.; Brewster, R.H.; Hyder, L.K.; Barnes, K.A.

    1981-10-01

    This annotated bibliography of 416 references represents the third in a series to be published by the Hazardous Materials Information Center containing scientific, technical, economic, and regulatory information relevant to low-level radioactive waste technology. The bibliography focuses on disposal site, environmental transport, and waste treatment studies as well as general reviews on the subject. The publication covers both domestic and foreign literature for the period 1951 to 1981. Major chapters selected are Chemical and Physical Aspects; Container Design and Performance; Disposal Site; Environmental Transport; General Studies and Reviews; Geology, Hydrology, and Site Resources; Regulatory and Economic Aspects; Social Aspects; Transportation Technology; Waste Production; and Waste Treatment. Entries in each of the chapters are further classified as a field study, laboratory study, theoretical study, or general overview involving one or more of these research areas.

  10. Definition of Local Diagnostic Reference Levels in a Radiology Department Using a Dose Tracking Software.

    PubMed

    Ghetti, C; Ortenzia, O; Palleri, F; Sireus, M

    2016-09-10

    Dose optimization in radiological examinations is a mandatory issue: in this study local Diagnostic Reference Levels (lDRLs) for Clinical Mammography (MG), Computed Tomography (CT) and Interventional Cardiac Procedures (ICP) performed in our Radiology Department were established. Using a dose tracking software, we have collected Average Glandular Dose (AGD) for two clinical mammographic units; CTDIvol, Size-Specific Dose Estimate (SSDE), Dose Length Product (DLP) and total DLP (DLPtot) for five CT scanners; Fluoro Time, Fluoro Dose Area Product (DAP) and total DAP (DAPtot) for two angiographic systems. Data have been compared with Italian Regulation and with the recent literature. The 75th percentiles of the different dosimetric indices have been calculated. Automated methods of radiation dose data collection allow a fast and detailed analysis of a great amount of data and an easy determination of lDRLs for different radiological procedures.

  11. Nanosecond-level time synchronization of AERA using a beacon reference transmitter and commercial airplanes

    NASA Astrophysics Data System (ADS)

    Huege, Tim

    2017-03-01

    Radio detection of cosmic-ray air showers requires time synchronization of detectors on a nanosecond level, especially for advanced reconstruction algorithms based on the wavefront curvature and for interferometric analysis approaches. At the Auger Engineering Radio Array, the distributed, autonomous detector stations are time-synchronized via the Global Positioning System which, however, does not provide sufficient timing accuracy. We thus employ a dedicated beacon reference transmitter to correct for eventby-event clock drifts in our offline data analysis. In an independent cross-check of this "beacon correction" using radio pulses emitted by commercial airplanes, we have shown that the combined timing accuracy of the two methods is better than 2 nanoseconds.

  12. Patient doses in paediatric CT: feasibility of setting diagnostic reference levels.

    PubMed

    Järvinen, H; Merimaa, K; Seuri, R; Tyrväinen, E; Perhomaa, M; Savikurki-Heikkilä, P; Svedström, E; Ziliukas, J; Lintrop, M

    2011-09-01

    Despite the fact that doses to paediatric patients from computed tomography (CT) examinations are of special concern, only few data or studies for setting of paediatric diagnostic reference levels (DRLs) have been published. In this study, doses to children were estimated from chest and head CT, in order to study the feasibility of DRLs for these examinations. It is shown that for the DRLs, patient dose data from different CT scanners should be collected in age or weight groups, possibly for different indications. For practical reasons, the DRLs for paediatric chest CT should be given as a continuous DRL curve as a function of patient weight. For paediatric head CT, DRLs for a few age groups could be given. The users of the DRLs should be aware of the calibration phantom applied in the console calibration for different paediatric scanning protocols. The feasibility of DRLs should be re-evaluated every 2-3 y.

  13. Reasoning in Reference Games: Individual- vs. Population-Level Probabilistic Modeling

    PubMed Central

    Franke, Michael; Degen, Judith

    2016-01-01

    Recent advances in probabilistic pragmatics have achieved considerable success in modeling speakers’ and listeners’ pragmatic reasoning as probabilistic inference. However, these models are usually applied to population-level data, and so implicitly suggest a homogeneous population without individual differences. Here we investigate potential individual differences in Theory-of-Mind related depth of pragmatic reasoning in so-called reference games that require drawing ad hoc Quantity implicatures of varying complexity. We show by Bayesian model comparison that a model that assumes a heterogenous population is a better predictor of our data, especially for comprehension. We discuss the implications for the treatment of individual differences in probabilistic models of language use. PMID:27149675

  14. THE APPLICATION OF DIAGNOSTIC REFERENCE LEVELS FOR OPTIMISATION OF X-RAY IMAGING IN THE UK.

    PubMed

    Martin, Colin J

    2016-06-01

    The concept of diagnostic reference levels (DRLs) has been introduced to provide standard doses against which hospital patient dose measurements can be compared to evaluate practices. DRLs are defined in terms of measured dose quantities. National DRLs can be derived from surveys of patient doses for common types of examinations in 20-30 large hospitals. The International Commission on Radiological Protection proposes that median doses for each type of examination at every hospital be collated and DRLs based on the third quartile value of the distribution. Once DRLs have been set, periodic audits of patient dose should be undertaken for examinations that reflect the clinical workload. Median doses from these distributions should be compared with relevant DRLs to identify procedures for which further optimisation is required and appropriate corrective action taken. This paper discusses factors that should be considered in the optimisation process and gives examples of experiences in application of DRLs in Scotland.

  15. Assessing data availability for the development of REDD-plus national reference levels

    PubMed Central

    2010-01-01

    Background Data availability in developing countries is known to be extremely varied and is one of the constraints for setting the national reference levels (RLs) for the REDD-plus (i.e. 'Policy approaches and positive incentives on issues relating to reducing emissions from deforestation and forest degradation in developing countries; and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries') under the UNFCCC. Taking Thailand as a case study country, this paper compares three types of RLs, which require different levels of datasets, including a simple historic RL, a projected forest-trend RL, and a business-as-usual (BAU) RL. Results Other than the finding that different RLs yielded different estimations on future deforestation areas, the analysis also identified the characteristics of each RL. The historical RL demanded simple data, but can be varied in accordance with a reference year or period. The forest-trend RL can be more reliable than the historical RL, if the country's deforestation trend curve is formed smoothly. The complicated BAU RL is useful as it can demonstrate the additionality of REDD-plus activities and distinguish the country's unintentional efforts. Conclusions With the REDD-plus that involves widespread participation, there should be steps from which countries choose the appropriate RL; ranging from simpler to more complex measures, in accordance with data availability in each country. Once registered with REDD-plus, the countries with weak capacity and capability should be supported to enhance the data collection system in that country. PMID:20920279

  16. Derivation of Australian diagnostic reference levels for paediatric multi detector computed tomography.

    PubMed

    Hayton, Anna; Wallace, Anthony

    2016-09-01

    Australian National Diagnostic Reference Levels for paediatric multi detector computed tomography were established for three protocols, Head, Chest and AbdoPelvis, across two age groups, Baby/Infant 0-4 years and Child 5-14 years by the Australian Radiation Protection and Nuclear Safety Agency in 2012. The establishment of Australian paediatric DRLs is an important step towards lowering patient CT doses on a national scale. While Adult DRLs were calculated with data collected from the web based Australian National Diagnostic Reference Level Service, no paediatric data was submitted in the first year of service operation. Data from an independent Royal Australian and New Zealand College of Radiologists Quality Use of Diagnostic Imaging paediatric optimisation survey was used. The paediatric DRLs were defined for CTDIvol (mGy) and DLP (mGy·cm) values that referenced the 16 cm PMMA phantom for the Head protocol and the 32 cm PMMA phantom for body protocols for both paediatric age groups. The Australian paediatric DRLs for multi detector computed tomography are for the Head, Chest and AbdoPelvis protocols respectively, 470, 60 and 170 mGy·cm for the Baby/Infant age group, and 600, 110 and 390 mGy·cm for the Child age group. A comparison with published international paediatric DRLs for computed tomography reveal the Australian paediatric DRLs to be lower on average. However, the comparison is complicated by misalignment of defined age ranges. It is the intention of ARPANSA to review the paediatric DRLs in conjunction with a review of the adult DRLs, which should occur within 5 years of their publication.

  17. Levels of seven urinary phthalate metabolites in a human reference population.

    PubMed Central

    Blount, B C; Silva, M J; Caudill, S P; Needham, L L; Pirkle, J L; Sampson, E J; Lucier, G W; Jackson, R J; Brock, J W

    2000-01-01

    Using a novel and highly selective technique, we measured monoester metabolites of seven commonly used phthalates in urine samples from a reference population of 289 adult humans. This analytical approach allowed us to directly measure the individual phthalate metabolites responsible for the animal reproductive and developmental toxicity while avoiding contamination from the ubiquitous parent compounds. The monoesters with the highest urinary levels found were monoethyl phthalate (95th percentile, 3,750 ppb, 2,610 microg/g creatinine), monobutyl phthalate (95th percentile, 294 ppb, 162 microg/g creatinine), and monobenzyl phthalate (95th percentile, 137 ppb, 92 microg/g creatinine), reflecting exposure to diethyl phthalate, dibutyl phthalate, and benzyl butyl phthalate. Women of reproductive age (20-40 years) were found to have significantly higher levels of monobutyl phthalate, a reproductive and developmental toxicant in rodents, than other age/gender groups (p < 0.005). Current scientific and regulatory attention on phthalates has focused almost exclusively on health risks from exposure to only two phthalates, di-(2-ethylhexyl) phthalate and di-isononyl phthalate. Our findings strongly suggest that health-risk assessments for phthalate exposure in humans should include diethyl, dibutyl, and benzyl butyl phthalates. PMID:11049818

  18. Indication-based diagnostic reference levels for adult CT-examinations in Finland.

    PubMed

    Lajunen, A

    2015-07-01

    A diagnostic reference level (DRL) is a predefined dose level, which should not be exceeded in an examination that is conducted appropriately on an average-sized patient. Since dose from only one examination should not be compared with a DRL, the average dose from a good sample of at least 10 average-sized patients should be compared. The previous DRLs for computed tomography (CT)-examinations for adults in Finland were issued in 2007 and only covered examinations conducted on a particular body region. Because the image quality requirements, and thus the dose needed, vary between different indications, there has been a call for indication-based DRLs for CT. The new indication-based DRLs for CT came into effect on June 2013. They are based on a dose survey performed in 2012. Doses were collected from examinations conducted on a particular body region, based on some indication and from some special examination types. The DRLs were set according to the third quartile approach. On average, the DRLs for a particular body region dropped ∼ 20 % from the previous DRLs.

  19. A study to establish international diagnostic reference levels for paediatric computed tomography.

    PubMed

    Vassileva, J; Rehani, M; Kostova-Lefterova, D; Al-Naemi, H M; Al Suwaidi, J S; Arandjic, D; Bashier, E H O; Kodlulovich Renha, S; El-Nachef, L; Aguilar, J G; Gershan, V; Gershkevitsh, E; Gruppetta, E; Hustuc, A; Jauhari, A; Kharita, Mohammad Hassan; Khelassi-Toutaoui, N; Khosravi, H R; Khoury, H; Kralik, I; Mahere, S; Mazuoliene, J; Mora, P; Muhogora, W; Muthuvelu, P; Nikodemova, D; Novak, L; Pallewatte, A; Pekarovič, D; Shaaban, M; Shelly, E; Stepanyan, K; Thelsy, N; Visrutaratna, P; Zaman, A

    2015-07-01

    The article reports results from the largest international dose survey in paediatric computed tomography (CT) in 32 countries and proposes international diagnostic reference levels (DRLs) in terms of computed tomography dose index (CTDI vol) and dose length product (DLP). It also assesses whether mean or median values of individual facilities should be used. A total of 6115 individual patient data were recorded among four age groups: <1 y, >1-5 y, >5-10 y and >10-15 y. CTDIw, CTDI vol and DLP from the CT console were recorded in dedicated forms together with patient data and technical parameters. Statistical analysis was performed, and international DRLs were established at rounded 75th percentile values of distribution of median values from all CT facilities. The study presents evidence in favour of using median rather than mean of patient dose indices as the representative of typical local dose in a facility, and for establishing DRLs as third quartile of median values. International DRLs were established for paediatric CT examinations for routine head, chest and abdomen in the four age groups. DRLs for CTDI vol are similar to the reference values from other published reports, with some differences for chest and abdomen CT. Higher variations were observed between DLP values, based on a survey of whole multi-phase exams. It may be noted that other studies in literature were based on single phase only. DRLs reported in this article can be used in countries without sufficient medical physics support to identify non-optimised practice. Recommendations to improve the accuracy and importance of future surveys are provided.

  20. Global Reference Frame Realization on National Level Based on the Integration of National CORS Networks

    NASA Astrophysics Data System (ADS)

    Kenyeres, A.; Caporali, A.; Horvath, T.; Baron, A.; Doncker, F. D.; Droscak, B.; Duret, A.; Franke, P.; Georgiev, I.; Gianniou, M.; Hansen, D.; Huisman, L.; Morozova, K.; Nagl, J.; Pihlak, P.; Stangl, G.; Valdes, M.; Ryczywolski, M.; Zurutuza, J.

    2015-12-01

    The national permanent GNSS networks are not only serving the general surveying practice in real-time mode, but they are deployed at reference frame maintenance and geodynamic studies relying on their homogeneously analyzed long-term data series. The ongoing EPN (EUREF Permanent Network) densification targets the integration of the national CORS networks and a homogeneous, dense position and velocity product is derived using the EPN as backbone infrastructure. The homogeneous cumulative solution relies on the national weekly SINEX products in order to minimize inconsistencies (e.g. site naming, discontinuities). The integration is done with the CATREF software (Altamimi et al, IGN) using the Minimum Constraint approach. The derived position and velocity product will be an essential material for various geokinematic studies (PGR, intraplate and plate boundary zone investigations), and also for the better realization of ETRS89 over tectonically active regions. This work is very well inline with the goals of other European initiatives as EPOS and EUPOS. The preparatory work is well in progress, several years of weekly SINEX files are already available and analyzed. The database contains more than 2000 stations stemming from 15 contributing Analysis Centres. A significant effort is devoted to the cleaning and organization of the station metadata and publish on the EPNCB website, which is necessary to improve the quality and reliabilty of the combination product.This presentation, beyond the publication of the state-of the-art combination results partly focuses on the analysis of existing reference frame realization issues caused by the GNSS antenna PCV updates not yet eliminated on the national CORS level.

  1. Dose Assessment in Computed Tomography Examination and Establishment of Local Diagnostic Reference Levels in Mazandaran, Iran

    PubMed Central

    Janbabanezhad Toori, A.; Shabestani-Monfared, A.; Deevband, M.R.; Abdi, R.; Nabahati, M.

    2015-01-01

    Background Medical X-rays are the largest man-made source of public exposure to ionizing radiation. While the benefits of Computed Tomography (CT) are well known in accurate diagnosis, those benefits are not risk-free. CT is a device with higher patient dose in comparison with other conventional radiation procedures. Objective This study is aimed at evaluating radiation dose to patients from Computed Tomography (CT) examination in Mazandaran hospitals and defining diagnostic reference level (DRL). Methods Patient-related data on CT protocol for four common CT examinations including brain, sinus, chest and abdomen & pelvic were collected. In each center, Computed Tomography Dose Index (CTDI) measurements were performed using pencil ionization chamber and CT dosimetry phantom according to AAPM report No. 96 for those techniques. Then, Weighted Computed Tomography Dose Index (CTDIW), Volume Computed Tomography Dose Index (CTDI vol) and Dose Length Product (DLP) were calculated. Results The CTDIw for brain, sinus, chest and abdomen & pelvic ranged (15.6-73), (3.8-25. 8), (4.5-16.3) and (7-16.3), respectively. Values of DLP had a range of (197.4-981), (41.8-184), (131-342.3) and (283.6-486) for brain, sinus, chest and abdomen & pelvic, respectively. The 3rd quartile of CTDIW, derived from dose distribution for each examination is the proposed quantity for DRL. The DRLs of brain, sinus, chest and abdomen & pelvic are measured 59.5, 17, 7.8 and 11 mGy, respectively. Conclusion Results of this study demonstrated large scales of dose for the same examination among different centers. For all examinations, our values were lower than international reference doses. PMID:26688796

  2. SU-E-P-10: Establishment of Local Diagnostic Reference Levels of Routine Exam in Computed Tomography

    SciTech Connect

    Yeh, M; Wang, Y; Weng, H

    2015-06-15

    Introduction National diagnostic reference levels (NDRLs) can be used as a reference dose of radiological examination can provide radiation dose as the basis of patient dose optimization. Local diagnostic reference levels (LDRLs) by periodically view and check doses, more efficiency to improve the way of examination. Therefore, the important first step is establishing a diagnostic reference level. Computed Tomography in Taiwan had been built up the radiation dose limit value,in addition, many studies report shows that CT scan contributed most of the radiation dose in different medical. Therefore, this study was mainly to let everyone understand DRL’s international status. For computed tomography in our hospital to establish diagnostic reference levels. Methods and Materials: There are two clinical CT scanners (a Toshiba Aquilion and a Siemens Sensation) were performed in this study. For CT examinations the basic recommended dosimetric quantity is the Computed Tomography Dose Index (CTDI). Each exam each different body part, we collect 10 patients at least. Carried out the routine examinations, and all exposure parameters have been collected and the corresponding CTDIv and DLP values have been determined. Results: The majority of patients (75%) were between 60–70 Kg of body weight. There are 25 examinations in this study. Table 1 shows the LDRL of each CT routine examination. Conclusions: Therefore, this study would like to let everyone know DRL’s international status, but also establishment of computed tomography of the local reference levels for our hospital, and providing radiation reference, as a basis for optimizing patient dose.

  3. Advancing reference emission levels in subnational and national REDD+ initiatives: a CLASlite approach.

    PubMed

    Reimer, Florian; Asner, Gregory P; Joseph, Shijo

    2015-12-01

    Conservation and monitoring of tropical forests requires accurate information on their extent and change dynamics. Cloud cover, sensor errors and technical barriers associated with satellite remote sensing data continue to prevent many national and sub-national REDD+ initiatives from developing their reference deforestation and forest degradation emission levels. Here we present a framework for large-scale historical forest cover change analysis using free multispectral satellite imagery in an extremely cloudy tropical forest region. The CLASlite approach provided highly automated mapping of tropical forest cover, deforestation and degradation from Landsat satellite imagery. Critically, the fractional cover of forest photosynthetic vegetation, non-photosynthetic vegetation, and bare substrates calculated by CLASlite provided scene-invariant quantities for forest cover, allowing for systematic mosaicking of incomplete satellite data coverage. A synthesized satellite-based data set of forest cover was thereby created, reducing image incompleteness caused by clouds, shadows or sensor errors. This approach can readily be implemented by single operators with highly constrained budgets. We test this framework on tropical forests of the Colombian Pacific Coast (Chocó) - one of the cloudiest regions on Earth, with successful comparison to the Colombian government's deforestation map and a global deforestation map.

  4. Multi-Component Molecular-Level Body Composition Reference Methods: Evolving Concepts and Future Directions

    PubMed Central

    Heymsfield, Steven B.; Ebbeling, Cara B.; Zheng, Jolene; Pietrobelli, Angelo; Strauss, Boyd J.; Silva, Analiza M.; Ludwig, David S.

    2015-01-01

    Excess adiposity is the main phenotypic feature that defines human obesity and that plays a pathophysiological role in most chronic diseases. Measuring the amount of fat mass present is thus a central aspect of studying obesity at the individual and population levels. Nevertheless, a consensus is lacking among investigators on a single accepted “reference” approach for quantifying fat mass in vivo. While the research community generally relies on the multicomponent body-volume class of “reference” models for quantifying fat mass, no definable guide discerns among different applied equations for partitioning the four (fat, water, protein, and mineral mass) or more quantified components, standardizes “adjustment” or measurement system approaches for model-required labeled water dilution volumes and bone mineral mass estimates, or firmly establishes the body temperature at which model physical properties are assumed. The resulting differing reference strategies for quantifying body composition in vivo leads to small but under some circumstances important differences in the amount of measured body fat. Recent technological advances highlight opportunities to expand model applications to new subject groups and measured components such as total body protein. The current report reviews the historical evolution of multicomponent body volume-based methods in the context of prevailing uncertainties and future potential. PMID:25645009

  5. Radiation safety concerns and diagnostic reference levels for computed tomography scanners in Tamil Nadu.

    PubMed

    Livingstone, Roshan S; Dinakaran, Paul M

    2011-01-01

    Radiation safety in computed tomography (CT) scanners is of concern due its widespread use in the field of radiological imaging. This study intends to evaluate radiation doses imparted to patients undergoing thorax, abdomen and pelvic CT examinations and formulate regional diagnostic reference levels (DRL) in Tamil Nadu, South India. In-site CT dose measurement was performed in 127 CT scanners in Tamil Nadu for a period of 2 years as a part of the Atomic Energy Regulatory Board (AERB)-funded project. Out of the 127 CT scanners,13 were conventional; 53 single-slice helical scanners (SSHS); 44 multislice CT (MSCT) scanners; and 17 refurbished scanners. CT dose index (CTDI) was measured using a 32-cm polymethyl methacrylate (PMMA)-body phantom in each CT scanner. Dose length product (DLP) for different anatomical regions was generated using CTDI values. The regional DRLs for thorax, abdomen and pelvis examinations were 557, 521 and 294 mGy cm, respectively. The mean effective dose was estimated using the DLP values and was found to be 8.04, 6.69 and 4.79 mSv for thorax, abdomen and pelvic CT examinations, respectively. The establishment of DRLs in this study is the first step towards optimization of CT doses in the Indian context.

  6. Establishment of diagnostic reference levels for dental panoramic radiography in Greece.

    PubMed

    Manousaridis, G; Koukorava, C; Hourdakis, C J; Kamenopoulou, V; Yakoumakis, E; Tsiklakis, K

    2015-07-01

    The purpose of the present study was to present the national diagnostic reference levels (DRL) established for panoramic dental examinations in Greece. The establishment of DRL, as a tool for the optimisation of radiological procedures, is a requirement of national regulations. Measurements performed by the Greek Atomic Energy Commission on 90 panoramic systems have been used for the derivation of DRL values. DRL values have been proposed for exposure settings of different patient types (child, small adult and standard adult), both for film and digital imaging. The DRLs for different patient types are grouped in three categories: children, small adults (corresponding to female) and average adults (corresponding to male). Proposed DRLs for these groups are 2.2, 3.3 and 4.1 mGy, respectively. In order to investigate the correlation of DRLs with the available imaging modalities (CR, DR and film), this parameter was taken into account. DR imaging DRL is the lowest at 3.5 mGy, CR imaging the highest at 4.2 mGy and film imaging at 3.7 mGy. In order to facilitate comparison with other studies, kerma-width product values were calculated from Ki, air and field size.

  7. Advancing reference emission levels in subnational and national REDD+ initiatives: a CLASlite approach

    PubMed Central

    Asner, Gregory P; Joseph, Shijo

    2015-01-01

    Conservation and monitoring of tropical forests requires accurate information on their extent and change dynamics. Cloud cover, sensor errors and technical barriers associated with satellite remote sensing data continue to prevent many national and sub-national REDD+ initiatives from developing their reference deforestation and forest degradation emission levels. Here we present a framework for large-scale historical forest cover change analysis using free multispectral satellite imagery in an extremely cloudy tropical forest region. The CLASlite approach provided highly automated mapping of tropical forest cover, deforestation and degradation from Landsat satellite imagery. Critically, the fractional cover of forest photosynthetic vegetation, non-photosynthetic vegetation, and bare substrates calculated by CLASlite provided scene-invariant quantities for forest cover, allowing for systematic mosaicking of incomplete satellite data coverage. A synthesized satellite-based data set of forest cover was thereby created, reducing image incompleteness caused by clouds, shadows or sensor errors. This approach can readily be implemented by single operators with highly constrained budgets. We test this framework on tropical forests of the Colombian Pacific Coast (Chocó) – one of the cloudiest regions on Earth, with successful comparison to the Colombian government’s deforestation map and a global deforestation map. PMID:25678933

  8. Diagnostic reference levels for thorax X-ray examinations of paediatric patients.

    PubMed

    Kiljunen, T; Järvinen, H; Savolainen, S

    2007-06-01

    Based on the Medical Exposure Directive of the European Commission, 97/43/Euratom, The Radiation and Nuclear Safety Authority (STUK) in Finland has the responsibility for setting national diagnostic reference levels (DRLs) for the most common radiological examinations. Paediatric patients deserve special attention because of the higher radiation risk compared with adults. The purpose of this paper is to present a method that takes into account patient size when setting DRLs in paediatric patients. The overall data consisted of patient doses collected from six hospitals during the years 1994-2001, and new measurements in two hospitals in 2004. In total, there were 700 chest examinations. The method established by the National Radiological Protection Board (UK) for setting DRLs was not considered feasible in Finnish practice. Patient doses correlated exponentially with the projection thickness, which was measured directly for each patient. Since 1 January 2006, paediatric DRLs for conventional chest examinations have been specified in Finland as a DRL curve by using both dose quantities (entrance surface doses (ESD) and dose-area product (DAP)) as a function of patient projection thickness.

  9. Out of Cite! How Reference Managers Are Taking Research to the Next Level

    ERIC Educational Resources Information Center

    Muldrow, Jason; Yoder, Stephen

    2009-01-01

    Times change, and so do research methods; gone are the days of researching with index cards. While academics may be slow to adopt emerging citation technology, the reference manager field is blazing ahead. This article explains what reference managers are, addresses their emergence in and potential impact on academe, and profiles a newcomer to the…

  10. SU-E-I-33: Establishment of CT Diagnostic Reference Levels in Province Nova Scotia

    SciTech Connect

    Tonkopi, E; Abdolell, M; Duffy, S

    2015-06-15

    Purpose: To evaluate patient radiation dose from the most frequently performed CT examinations and to establish provincial diagnostic reference levels (DRLs) as a tool for protocol optimization. Methods: The study investigated the following CT examinations: head, chest, abdomen/pelvis, and chest/abdomen/pelvis (CAP). Dose data, volume CT dose index (CTDIvol) and dose-length product (DLP), were collected from 15 CT scanners installed during 2004–2014 in 11 hospital sites of Nova Scotia. All scanners had dose modulation options and multislice capability (16–128 detector rows). The sample for each protocol included 15 average size patients (70±20 kg). Provincial DRLs were calculated as the 75th percentile of patient dose distributions. The differences in dose between hospitals were evaluated with a single factor ANOVA statistical test. Generalized linear modeling was used to determine the factors associated with higher radiation dose. A sample of 36 abdominal studies performed on three different scanners was blinded and randomized for an assessment by an experienced radiologist who graded the imaging quality of anatomic structures. Results: Data for 900 patients were collected. The DRLs were proposed using CTDIvol (mGy) and DLP (mGy*cm) values for CT head (67 and 1049, respectively), chest (12 and 393), abdomen/pelvis (16 and 717), and CAP (14 and 1034). These DRLs were lower than the published national data except for the head CTDIvol. The differences between the means of the dose distributions from each scanner were statistically significant (p<0.05) for all examinations. A very weak correlation was found between the dose and the scanner age or the number of slices with Pearson’s correlation coefficients of 0.011–0.315. The blinded analysis of image quality demonstrated no clinically significant difference except for the noise category. Conclusion: Provincial DRLs were established for typical CT examinations. The variations in dose between the hospitals

  11. U.S. Diagnostic Reference Levels and Achievable Doses for 10 Adult CT Examinations.

    PubMed

    Kanal, Kalpana M; Butler, Priscilla F; Sengupta, Debapriya; Bhargavan-Chatfield, Mythreyi; Coombs, Laura P; Morin, Richard L

    2017-02-21

    Purpose To develop diagnostic reference levels (DRLs) and achievable doses (ADs) for the 10 most common adult computed tomographic (CT) examinations in the United States as a function of patient size by using the CT Dose Index Registry. Materials and Methods Data from the 10 most commonly performed adult CT head, neck, and body examinations from 583 facilities were analyzed. For head examinations, the lateral thickness was used as an indicator of patient size; for neck and body examinations, water-equivalent diameter was used. Data from 1 310 727 examinations (analyzed by using SAS 9.3) provided median values, as well as means and 25th and 75th (DRL) percentiles for volume CT dose index (CTDIvol), dose-length product (DLP), and size-specific dose estimate (SSDE). Applicable results were compared with DRLs from eight countries. Results More than 46% of the facilities were community hospitals; 13% were academic facilities. More than 48% were in metropolitan areas, 39% were suburban, and 13% were rural. More than 50% of the facilities performed fewer than 500 examinations per month. The abdomen and pelvis was the most frequently performed examination in the study (45%). For body examinations, DRLs (75th percentile) and ADs (median) for CTDIvol, SSDE, and DLP increased consistently with the patient's size (water-equivalent diameter). The relationships between patient size and DRLs and ADs were not as strong for head and neck examinations. These results agree well with the data from other countries. Conclusion DRLs and ADs as a function of patient size were developed for the 10 most common adult CT examinations performed in the United States. (©) RSNA, 2017.

  12. Dose-Response Relationship between Alanine Aminotransferase Levels within the Reference Interval and Metabolic Syndrome in Chinese Adults

    PubMed Central

    Wu, Peipei; Chen, Qicai; Chen, Lili; Zhang, Pengpeng; Xiao, Juan; Chen, Xiaoxiao; Liu, Meng

    2017-01-01

    Purpose Elevation in serum alanine aminotransferase (ALT) levels is a biomarker for metabolic syndrome (MS); however, the relationship has not been fully investigated within the reference interval of ALT levels. Our objective was to explore the relationship between serum ALT levels within the reference interval and MS in Chinese adults. Materials and Methods This cross-sectional study included 16028 adults, who attended routine health check-ups at Shengli Oilfield Central Hospital from January 2006 to March 2012. The reference interval of serum ALT level was defined as less than 40 U/L. Logistic regression models and restricted cubic spline were used to evaluate the association of ALT with MS. Results The prevalence of MS in the total population was 13.7% (6.4% for females and 18.4% for males). Multiple logistic regression showed that ALT levels were positively associated with MS after adjustment for potential confounding factors. The odds ratio of MS in the top quartile was 4.830 [95% confidence interval (CI): 2.980–7.829] in females and 3.168 (95% CI: 2.649–3.790) in males, compared with the ALT levels in the bottom quartile. The restricted cubic spline models revealed a positive non-linear dose-response relationship between ALT levels and the risk of MS in women (p for nonlinearity was 0.0327), but a positive linear dose-response relationship in men (p for nonlinearity was 0.0659). Conclusion Serum ALT levels within the reference interval are positively associated with MS in a dose-response manner. Elevated ALT levels, even within the reference interval, may reflect early dysmetabolic changes. PMID:27873509

  13. Commentary Variations: Level of Verbalization, Personal Reference, and Phase Relations in Instructional Films on Perceptual-Motor Tasks. Technical Report.

    ERIC Educational Resources Information Center

    Zuckerman, John V.

    In an experiment to determine the most efficient design for the commentary of an instructional film, special consideration was given to three variables concerned with the construction of commentaries: the level of verbalization (the amount of talk), the personal reference of the narrator, and the phase relationship between the commentary and the…

  14. The Relationship Between Global Mean Sea Level Rise and the Reference Frame

    NASA Technical Reports Server (NTRS)

    Lemoine, F.; Luthcke, S.; Zelensky, N.; Pavlis, E.; Beckley, B.; Ray, R.; Petrov, L.; Pavlis, D.; Rowlands, D.

    2006-01-01

    The Terrestrial Reference Frame is the fundamental means by which we relate observations in space and time. For example, in order to generate a homogeneous and consistent time series of geo-referenced altimeter measurements over the span of the Topex/Poseidon and Jason-1 missions, we must examine carefully the role of improvements in measurement modelling, force modelling, and improved reference frame realizations. In this paper, we quantify the effects of improvements in force modelling, for example the use of new GRACE-derived gravity models, the effect of time-variable gravity derived from GRACE on altimeter satellite orbits. In addition, we examine the effects of modelling geocenter in altimeteric satellite POD, and look at how the application of atmospheric loading might affect the time-series of precise orbits for Topex/Poseidon and Jason-1.

  15. Progress towards an alanine/ESR therapy level reference dosimetry service at NPL.

    PubMed

    Sharpe, P H; Rajendran, K; Sephton, J P

    1996-01-01

    This paper describes work being carried out at the National Physical Laboratory towards the establishment of an alanine reference dosimetry service for radiotherapy applications. A precision fused quartz holder has been constructed to allow precise positioning of alanine dosimeters in the ESR cavity. A novel method of signal analysis based on spectrum fitting has been developed to minimize the effect of baseline distortions. Data are also presented on the relative response of alanine to 60Co gamma rays and high energy photons (4-12 MeV).

  16. Parallel implementation of multireference coupled-cluster theories based on the reference-level parallelism

    SciTech Connect

    Brabec, Jiri; Pittner, Jiri; van Dam, Hubertus JJ; Apra, Edoardo; Kowalski, Karol

    2012-02-01

    A novel algorithm for implementing general type of multireference coupled-cluster (MRCC) theory based on the Jeziorski-Monkhorst exponential Ansatz [B. Jeziorski, H.J. Monkhorst, Phys. Rev. A 24, 1668 (1981)] is introduced. The proposed algorithm utilizes processor groups to calculate the equations for the MRCC amplitudes. In the basic formulation each processor group constructs the equations related to a specific subset of references. By flexible choice of processor groups and subset of reference-specific sufficiency conditions designated to a given group one can assure optimum utilization of available computing resources. The performance of this algorithm is illustrated on the examples of the Brillouin-Wigner and Mukherjee MRCC methods with singles and doubles (BW-MRCCSD and Mk-MRCCSD). A significant improvement in scalability and in reduction of time to solution is reported with respect to recently reported parallel implementation of the BW-MRCCSD formalism [J.Brabec, H.J.J. van Dam, K. Kowalski, J. Pittner, Chem. Phys. Lett. 514, 347 (2011)].

  17. Determination of diagnostic reference levels in general radiography in Latin America.

    PubMed

    Blanco, Susana; Mora, Patricia; Almonte, Narkiss; Benavente, Tony; Benson, Nadja; Blanco, Daniel; Cárdenas, Juan; Defaz Gómez, Yolanda; Edding, Oscar; Escobar, Carolina; Fonseca, María; Gamarra, Mirtha; García Aguilar, Juan; Khoury, Helen Jamil; Quintero, Ana Rosa; Roas Zuniga, Norma; Zaire, Edgar; Nader, Alejandro

    2013-09-01

    The International Atomic Energy Agency (IAEA) through the International Action Plan on Radiation Protection of Patients and the International Commission on Radiological Protection have for some time carried out important efforts to assure that in the medical applications of the ionising radiations, the optimisation of radiological protection of patients is fundamental, to such a point that the IAEA includes it directly as a requirement for these practices (in its International Basic Safety Standards for Protection against Ionising Radiation and for the Safety of Radiation Sources (BSS)-GSR Part 1, 2011). For this reason, among the objectives of Regional Project RLA/9/057 and Regional Project RLA/9/067, the intention was to establish the dose references in conventional radiology for Latin America, for the purposes of determining whether these doses comply with the requirements of the BSS and to tend to improve practices, in order to minimise the dose received by the patients.

  18. Post-mortem urinary myoglobin levels with reference to the causes of death.

    PubMed

    Zhu, B L; Ishida, K; Quan, L; Taniguchi, M; Oritani, S; Kamikodai, Y; Fujita, M Q; Maeda, H

    2001-01-15

    To evaluate pathophysiological significance of post-mortem urinary myoglobin levels in determining the cause of death, we investigated 210 forensic autopsy cases, partially in comparison with serum levels. Post-mortem serum myoglobin levels were extraordinary high in most cases possibly due to post-mortem change. Urinary myoglobin levels did not correlate with the serum levels, showing possible post-mortem elevation in cases of a prolonged post-mortem period over 48h. A high (>1000 ng/ml), moderate (100-1000 ng/ml), slight (50-100 ng/ml) and not significant (<50 ng/ml) elevation of urinary myoglobin were observed in 26, 43, 31 and 110 cases, respectively. Half the highly elevated cases were those with a survival time over 24h. In cases of minor muscle injury such as head trauma, elevation of urinary myoglobin level was closely related to longer survival. In acute/subacute deaths with a post-mortem interval within 48h, a significant difference was observed in relation to the blood carboxyhemoglobin (COHb) levels of fire victims: myoglobinuria over 100 ng/ml was more frequently and markedly observed in cases with COHb below 60% than over 60%, suggesting muscle damage in fatal burns. Similar elevation was observed in heat stroke victims, and also in some cases of acute and subacute death from polytrauma, asphyxiation, drowning, electricity and spontaneous cerebral bleeding, but not in myocardial infarction. Thus, it was suggested that high post-mortem urinary myoglobin levels in acute and subacute death cases may be a possible indicator of antemortem massive skeletal muscle damage as well as exertional muscle hyperactivity or convulsive disorders associated with hypoxia.

  19. Reference points suitable for evaluation of the additional arch length required for leveling the curve of Spee

    PubMed Central

    Cho, Yong-Hwa; Gang, Sung-Nam

    2016-01-01

    Objective The additional arch length required for leveling (AALL) the curve of Spee (COS) can be estimated by subtracting the two-dimensional (2D) arch circumference, which is the projection of the three-dimensional (3D) arch circumference onto the occlusal plane, from the 3D arch circumference, which represents the arch length after leveling the COS. The purpose of this study was to determine whether the cusp tips or proximal maximum convexities are more appropriate reference points for estimating the AALL. Methods Sixteen model setups of the mandibular arch with COS depths ranging from 0 mm to 4.7 mm were constructed using digital simulation. Arch circumferences in 2D and 3D were measured from the cusp tips and proximal maximum convexities and used to calculate the AALL. The values obtained using the two reference points were compared with the paired t-test. Results Although the 3D arch circumference should be constant regardless of the COS depth, it decreased by 3.8 mm in cusp tip measurements and by 0.4 mm in proximal maximum convexity measurements as the COS deepened to 4.7 mm. AALL values calculated using the cusp tips as reference points were significantly smaller than those calculated using the proximal maximum convexities (p = 0.002). Conclusions The AALL is underestimated when the cusp tips are used as measurement reference points; the AALL can be measured more accurately using the proximal maximum convexities. PMID:27896209

  20. Reference range levels of polycyclic aromatic hydrocarbons in the US population by measurement of urinary monohydroxy metabolites

    SciTech Connect

    Grainger, James . E-mail: jag2@cdc.gov; Huang, Wenlin; Patterson, Donald G.; Turner, Wayman E.; Pirkle, James; Caudill, Samuel P.; Wang, Richard Y.; Needham, Larry L.; Sampson, Eric J.

    2006-03-15

    We developed a gas chromatography isotope-dilution high-resolution mass spectrometry (GC/Id-HRMS) method for measuring 14 polycyclic aromatic hydrocarbon (PAH) metabolites representing seven parent PAHs in 3 mL of urine at low parts-per-trillion levels. PAH levels were determined in urine samples collected in 1999 and 2000 from approximately 2400 participants in the National Health and Nutrition Examination Survey, and, for the first time, reference range values were calculated for these metabolites in the US population. Using this GC/ID-HRMS method, we found detectable concentrations for monohydroxy metabolite isomers of fluorene, phenanthrene, fluoranthene, pyrene, and chrysene, benzo[c]phenanthrene, and benz[a]anthracene. Some monohydroxy metabolite isomers of benzo[c]phenanthrene, chrysene, and benz[a]anthracene exhibited low detection frequencies that did not allow for geometric mean calculations. Our study results enabled us to establish a reference range for the targeted PAHs in the general US population.

  1. DEVELOPMENT OF TOXICITY REFERENCE VALUES FOR ECOLOGICAL SOIL SCREENING LEVELS (ECO-SSLS) FOR TERRESTRIAL WILDLIFE

    EPA Science Inventory

    Ecological Soil Screening Levels (Eco-SSLs) protective of terrestrial wildlife were developed by the USEPA Superfund. The wildlife Eco-SSL is the soil contaminant concentration where the Effect Dose (TRV) and Exposure Dose are equal (amount of contaminant in the diet that is take...

  2. Airport-Noise Levels and Annoyance Model (ALAMO) system's reference manual

    NASA Technical Reports Server (NTRS)

    Deloach, R.; Donaldson, J. L.; Johnson, M. J.

    1986-01-01

    The airport-noise levels and annoyance model (ALAMO) is described in terms of the constituent modules, the execution of ALAMO procedure files, necessary for system execution, and the source code documentation associated with code development at Langley Research Center. The modules constituting ALAMO are presented both in flow graph form, and through a description of the subroutines and functions that comprise them.

  3. The Effect of Exposure on EFL Learners' Acquisition of Idioms with Reference to Proficiency Levels.

    ERIC Educational Resources Information Center

    Atai, Mahmood Reza; Akbarian, Ishaq

    2003-01-01

    Investigated the probable effect of different contexts on learning idioms, as well as the interaction between learning idioms in different contexts and English-as-a-Foreign-Language (EFL) learners' language proficiency. Findings revealed that different contexts and proficiency levels had significant effects on EFL learners' acquisition of idioms;…

  4. Centimeter-Level Robust Gnss-Aided Inertial Post-Processing for Mobile Mapping Without Local Reference Stations

    NASA Astrophysics Data System (ADS)

    Hutton, J. J.; Gopaul, N.; Zhang, X.; Wang, J.; Menon, V.; Rieck, D.; Kipka, A.; Pastor, F.

    2016-06-01

    For almost two decades mobile mapping systems have done their georeferencing using Global Navigation Satellite Systems (GNSS) to measure position and inertial sensors to measure orientation. In order to achieve cm level position accuracy, a technique referred to as post-processed carrier phase differential GNSS (DGNSS) is used. For this technique to be effective the maximum distance to a single Reference Station should be no more than 20 km, and when using a network of Reference Stations the distance to the nearest station should no more than about 70 km. This need to set up local Reference Stations limits productivity and increases costs, especially when mapping large areas or long linear features such as roads or pipelines. An alternative technique to DGNSS for high-accuracy positioning from GNSS is the so-called Precise Point Positioning or PPP method. In this case instead of differencing the rover observables with the Reference Station observables to cancel out common errors, an advanced model for every aspect of the GNSS error chain is developed and parameterized to within an accuracy of a few cm. The Trimble Centerpoint RTX positioning solution combines the methodology of PPP with advanced ambiguity resolution technology to produce cm level accuracies without the need for local reference stations. It achieves this through a global deployment of highly redundant monitoring stations that are connected through the internet and are used to determine the precise satellite data with maximum accuracy, robustness, continuity and reliability, along with advance algorithms and receiver and antenna calibrations. This paper presents a new post-processed realization of the Trimble Centerpoint RTX technology integrated into the Applanix POSPac MMS GNSS-Aided Inertial software for mobile mapping. Real-world results from over 100 airborne flights evaluated against a DGNSS network reference are presented which show that the post-processed Centerpoint RTX solution agrees with

  5. Histamine levels in commercially important fresh and processed fish of Oman with reference to international standards.

    PubMed

    Yesudhason, Poulose; Al-Zidjali, Mehdia; Al-Zidjali, Alia; Al-Busaidi, Moza; Al-Waili, Aaliah; Al-Mazrooei, Nashwa; Al-Habsi, Saoud

    2013-10-15

    Histamine was investigated in fresh (378), frozen (441), canned (290) and dried (24) fish samples of scombroid and non-scombroid species of Oman using a high performance liquid chromatography with a fluorescence detector. Of the 1133 fish samples tested, histamine was detected in 551 samples with a detection rate of about 41.8% among fresh fish, 61.0% of frozen fish, 78.9% of canned fish and 91.6% of dried fish samples and the mean histamine levels were 2.6, 5.8, 3.1 and 104mgkg(-1), respectively. A total of 3.7% and 0.79% of the total samples exceeded the FDA and EU regulatory limits for histamine. Imported dried anchovies contained high histamine levels. The study confirms that post catching and commercialisation practices of seafood are adequate, warranting good quality fish and may not cause histamine risk to consumer in terms of human diet. While necessary monitoring may be done for imported dried fish products.

  6. Ultraclean wafer-level vacuum-encapsulated silicon ring resonators for timing and frequency references

    NASA Astrophysics Data System (ADS)

    Xereas, George; Chodavarapu, Vamsy P.

    2016-07-01

    We present the design and development of breath-mode silicon ring resonators fabricated using a commercial pure-play microfabrication process that provides ultraclean wafer-level vacuum-encapsulation. The micromechanical resonators are fabricated in MEMS integrated design for inertial sensors process that is developed by Teledyne DALSA Semiconductor Inc. The ring resonators are designed to operate with a relatively low DC polarization voltage, starting at 5 V, while providing a high frequency-quality factor product. We study the quality of the vacuum packaging using an automated testing setup over an extended time period. We study the effect of motional resistance on the performance of MEMS resonators. The fabricated devices had a resonant frequency of 10 MHz with the quality factor exceeding 8.4×104.

  7. Evaluation of alanine as a reference dosimeter for therapy level dose comparisons in megavoltage electron beams

    NASA Astrophysics Data System (ADS)

    McEwen, Malcolm; Sharpe, Peter; Vörös, Sándor

    2015-04-01

    When comparing absorbed dose standards from different laboratories (e.g. National Measurement Institutes, NMIs, for Key or Supplementary comparisons) it is rarely possible to carry out a direct comparison of primary standard instruments, and therefore some form of transfer detector is required. Historically, air-filled, unsealed ionization chambers have been used because of the long history of using these instruments, very good stability over many years, and ease of transport. However, the use of ion chambers for therapy-level comparisons is not without its problems. Findings from recent investigations suggest that ion chambers are prone to non-random variations, they are not completely robust to standard courier practices, and failure at any step in a comparison can render all measurements potentially useless. An alternative approach is to identify a transfer system that is insensitive to some of these concerns—effectively a dosimeter that is inexpensive, simple to use, robust, but with sufficient precision and of a size relevant to the disseminated quantity in question. The alanine dosimetry system has been successfully used in a number of situations as an audit dosimeter and therefore the purpose of this investigation was to determine whether alanine could also be used as the transfer detector for dosimetric comparisons, which require a lower value for the measurement uncertainty. A measurement protocol was developed for comparing primary standards of absorbed dose to water in high-energy electron beams using alanine pellets irradiated in a water-equivalent plastic phantom. A trial comparison has been carried out between three NMIs and has indicated that alanine is a suitable alternative to ion chambers, with the system used achieving a precision of 0.1%. Although the focus of the evaluation was on the performance of the dosimeter, the comparison results are encouraging, showing agreement at the level of the combined uncertainties (~0.6%). Based on this

  8. Results of a survey on the implementation of diagnostic reference levels for X-rays among Dutch hospitals.

    PubMed

    Bijwaard, Harmen; Valk, Doreth; de Waard-Schalkx, Ischa

    2015-04-01

    Diagnostic reference levels (DRLs) for medical x-ray procedures are being implemented currently in the Netherlands. By order of the Dutch Healthcare Inspectorate, a survey has been conducted among 20 Dutch hospitals to investigate the level of implementation of the Dutch DRLs in current radiological practice. It turns out that hospitals are either well underway in implementing the DRLs or have already done so. However, the DRLs have usually not yet been incorporated in the QA system of the department nor in the treatment protocols. It was shown that the amount of radiation used, as far as it was indicated by the hospitals, usually remains below the DRLs. A procedure for comparing dose levels to the DRLs has been prescribed but is not always followed in practice. This is especially difficult in the case of children, as most general hospitals receive few children.

  9. Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods

    SciTech Connect

    Mai, Sebastian; Marquetand, Philipp; González, Leticia; Müller, Thomas; Plasser, Felix; Lischka, Hans

    2014-08-21

    An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the COLUMBUS quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbit coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations.

  10. PAEDIATRIC CT EXPOSURE PRACTICE IN THE COUNTY OF RIO DE JANEIRO: THE NEED TO ESTABLISH DIAGNOSTIC REFERENCE LEVELS.

    PubMed

    de Jesus, Fillipe M; Magalhães, Luis A G; Kodlulovich, Simone

    2016-11-01

    A pilot study of dose indicators in paediatric computed tomography (CT) was conducted to prove the need to establish diagnostic reference levels (DRLs) for the county of Rio de Janeiro. The dose descriptors were estimated from the beam dosimetry by applying the protocols used in each examination. The total patient sample included 279 children. Regarding the comparison of the dose-length product values among the hospitals, the high-resolution chest CT scans were distinguished among the three types of examinations, due to the discrepancies of 1148 % (1-5 y age group) and 2248 % (5-10 y age group) presented in Hospital A's dose-length product values relative to Hospital D's dose-length product values. The results showed that without DRL, the dose variation can be significant between hospitals in the same county for the same age group in the same examination.

  11. Reference levels for corticosterone and immune function in farmed saltwater crocodiles (Crocodylus porosus) hatchlings using current Code of Practice guidelines.

    PubMed

    Finger, John W; Thomson, Peter C; Adams, Amanda L; Benedict, Suresh; Moran, Christopher; Isberg, Sally R

    2015-02-01

    To determine reference levels for on-farm stressors on immune responsiveness and growth rate, 253 hatchling crocodiles from 11 known breeding pairs were repeatedly measured and blood sampled during their first year. Plasma corticosterone (CORT) was used to quantify baseline stress levels in captive animals and were found to be lower (mean 1.83±SE 0.16 ng/mL) than previously reported in saltwater crocodile hatchlings. Two tests of immune function were also conducted. Innate constitutive immunity was assessed using bacterial killing assays (BKA) against two bacterial species: Escherichia coli and Providencia rettgeri, whereby the latter causes considerable economic loss to industry from septicaemic mortalities. Although the bactericidal capabilities were different at approximately 4 months old (32±3% for E. coli and 16±4% for P. rettgeri), the differences had disappeared by approximately 9 months old (58±2% and 68±6%, respectively). To assess immune responsiveness to a novel antigen, the inflammatory swelling response caused by phytohaemagglutinin (PHA) injection was assessed but was only significantly different between Samplings 1 and 3 (5% LSD). There were no significant clutch effects for CORT or PHA but there were for both BKA traits. CORT was not significantly associated with growth (head length) or the immune parameters except for P. rettgeri BKA where higher CORT levels were associated with better bactericidal capability. As such, these results suggest that the crocodiles in this study are not stressed, therefore endorsing the management strategies adopted within the Australian industry Code of Practice.

  12. ESTIMATION OF CARDIAC CT ANGIOGRAPHY RADIATION DOSE TOWARD THE ESTABLISHMENT OF NATIONAL DIAGNOSTIC REFERENCE LEVEL FOR CCTA IN IRAN.

    PubMed

    Hosseini Nasab, Seyed Mohammad Bagher; Shabestani-Monfared, Ali; Deevband, Mohammad Reza; Paydar, Reza; Nabahati, Mehrdad

    2016-08-29

    In recent years, with the introduction of 64-slice CT and dual-source CT technology, coronary CT angiography (CCTA) has emerged as a useful diagnostic imaging modality as a non-invasive assessment of coronary heart disease. CT produces a larger radiation dose than other imaging tests and cardiac CT involves higher radiation dose with the advances in the spatial and temporal resolution. The aims of this study are patient dose assessment and establishment of national diagnostic reference level for CCTA in Iran. A questionnaire was sent to CCTA centers. Data for patient and CT protocols were obtained. The volumetric CT dose index (CTDIvol), dose length product (DLP) and total DLP were considered in the 32 cm standard body phantom. Calculation of estimated effective dose (ED) was obtained by multiplying the DLP by a conversion factor [k = 0.014 mSv (mGy·cm)(-1)]. Mean value of CTDIvol and DLP for CCTA was 50 mGy and 825 mGy·cm. The third quartile (75th) of the distribution of mean CTDIvol (66.54 mGy) and DLP (1073 mGy·cm) values was expressed as the diagnostic reference level (DRL) for CCTA in Iran. The median of ED was 10.26 mSv and interquartile range of ED was 7.08-15.03 mSv. A large variety in CTDIvol and DLP among CT scanner and different sites due to variability in CT parameter is noted. It seems that training could help to reduce patient's dose.

  13. Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

    SciTech Connect

    Fabrikant, J.I.

    1982-04-01

    Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation. (ERB)

  14. Sensitivity of ecological soil-screening levels for metals to exposure model parameterization and toxicity reference values.

    PubMed

    Sample, Bradley E; Fairbrother, Anne; Kaiser, Ashley; Law, Sheryl; Adams, Bill

    2014-10-01

    Ecological soil-screening levels (Eco-SSLs) were developed by the United States Environmental Protection Agency (USEPA) for the purposes of setting conservative soil screening values that can be used to eliminate the need for further ecological assessment for specific analytes at a given site. Ecological soil-screening levels for wildlife represent a simplified dietary exposure model solved in terms of soil concentrations to produce exposure equal to a no-observed-adverse-effect toxicity reference value (TRV). Sensitivity analyses were performed for 6 avian and mammalian model species, and 16 metals/metalloids for which Eco-SSLs have been developed. The relative influence of model parameters was expressed as the absolute value of the range of variation observed in the resulting soil concentration when exposure is equal to the TRV. Rank analysis of variance was used to identify parameters with greatest influence on model output. For both birds and mammals, soil ingestion displayed the broadest overall range (variability), although TRVs consistently had the greatest influence on calculated soil concentrations; bioavailability in food was consistently the least influential parameter, although an important site-specific variable. Relative importance of parameters differed by trophic group. Soil ingestion ranked 2nd for carnivores and herbivores, but was 4th for invertivores. Different patterns were exhibited, depending on which parameter, trophic group, and analyte combination was considered. The approach for TRV selection was also examined in detail, with Cu as the representative analyte. The underlying assumption that generic body-weight-normalized TRVs can be used to derive protective levels for any species is not supported by the data. Whereas the use of site-, species-, and analyte-specific exposure parameters is recommended to reduce variation in exposure estimates (soil protection level), improvement of TRVs is more problematic.

  15. Sensitivity of ecological soil-screening levels for metals to exposure model parameterization and toxicity reference values

    PubMed Central

    Sample, Bradley E; Fairbrother, Anne; Kaiser, Ashley; Law, Sheryl; Adams, Bill

    2014-01-01

    Ecological soil-screening levels (Eco-SSLs) were developed by the United States Environmental Protection Agency (USEPA) for the purposes of setting conservative soil screening values that can be used to eliminate the need for further ecological assessment for specific analytes at a given site. Ecological soil-screening levels for wildlife represent a simplified dietary exposure model solved in terms of soil concentrations to produce exposure equal to a no-observed-adverse-effect toxicity reference value (TRV). Sensitivity analyses were performed for 6 avian and mammalian model species, and 16 metals/metalloids for which Eco-SSLs have been developed. The relative influence of model parameters was expressed as the absolute value of the range of variation observed in the resulting soil concentration when exposure is equal to the TRV. Rank analysis of variance was used to identify parameters with greatest influence on model output. For both birds and mammals, soil ingestion displayed the broadest overall range (variability), although TRVs consistently had the greatest influence on calculated soil concentrations; bioavailability in food was consistently the least influential parameter, although an important site-specific variable. Relative importance of parameters differed by trophic group. Soil ingestion ranked 2nd for carnivores and herbivores, but was 4th for invertivores. Different patterns were exhibited, depending on which parameter, trophic group, and analyte combination was considered. The approach for TRV selection was also examined in detail, with Cu as the representative analyte. The underlying assumption that generic body-weight–normalized TRVs can be used to derive protective levels for any species is not supported by the data. Whereas the use of site-, species-, and analyte-specific exposure parameters is recommended to reduce variation in exposure estimates (soil protection level), improvement of TRVs is more problematic. Environ Toxicol Chem 2014

  16. Technology, Safety and Costs of Decommissioning a Reference Low-Level Waste Burial Ground Environmental Surveillance Programs

    SciTech Connect

    Denham, D. H.; Eddy, P. A.; Hawley, K. A.; Jaquish, R. E.; Corley, J. P.

    1981-07-01

    This Addendum supplements, and to some extent replaces, the preliminary description of environmental radiological surveillance programs for low-level waste burial grounds (LLWBG) used in the parent document, 11 Technology, Safety and Costs of DecolliTlissioning a Reference Low-Level Waste Burial Ground, 11 NUREG/ CR-0570. The Addendum provides additional detail and rationale for the environmental radiological surveillance programs for the two referenced sites and inventories described in NUREG/CR-0570. The rationale and performance criteria herein are expected to be useful in providing guidance for determining the acceptability of environmental surveillance programs for other inventories and other LLWBG sites. Two generic burial grounds, one located on an arid western site and the other located on a humid eastern site, are reference facilities considered in this Addendum, and as described in the parent document (NUREG/CR-0570). The two sites are assumed to have the same capacity for waste, the same radioactive waste inventory, and similar trench characteristics and operating procedures. The climate, geology, and hydrology of the two reference sites are typical of existing western and eastern sites, altnough a single population distribution was chosen for both. Each reference burial ground occupies about 70 hectares and includes 180 trenches filled with a total of 1.5 x 10{sup 6} m{sup 3} of radioactive waste. In acldition, there are 10 slit trenches containing about 1.5 x 10{sup 3} m{sup 3} of high beta-gamma activity waste. In this Addendum environmental surveillance programs are described for the several periods in the life of a LLWBG: preoperational (prior to nuclear waste receipt); operational (including interim trench closures); post-operational (after all nuclear waste is received), for both short-term {up to three years) and long-term (up to 100 years) storage and custodial care; and decommissioning (only for the special case of waste removal). The specific

  17. On the certification of cadmium at trace and ultratrace levels in standard reference materials using ID ICP-MS.

    PubMed

    Murphy, K E; Long, S E; Vocke, R D

    2007-04-01

    Analytical methods used for the isotope dilution inductively coupled plasma mass spectrometric (ID-ICP-MS) measurement of Cd at microg kg(-1) and sub-microg kg(-1) levels are described and applied to the certification of new dietary supplement, blood, and serum Standard Reference Materials (SRMs). The materials are: SRM 3240 Ephedra sinica Stapf Aerial Parts, SRM 3241 Ephedra sinica Stapf Native Extract, SRM 3243 Ephedra-Containing Solid Oral Dosage Form, SRM 3244 Ephedra-Containing Protein Powder, SRM 966 Toxic Metals in Bovine Blood, Level 1 (L1) and Level 2 (L2), and SRM 1598a Animal Serum. The concentration of Cd in the materials ranges from 120 microg kg(-1) down to 0.03 microg kg(-1). At these levels, the factors that most influence the accuracy of the ICP-MS data are the procedure blank and spectral and nonspectral interferences. Nonspectral interference, caused by the high concentration of dissolved solids in the matrices investigated, resulted in signal suppression. Matrix separation was used to enhance signal intensity and to reduce spectral interference for the accurate determination of Cd in SRM 1598a and SRM 3244. Chromatographic separation procedures using Chelex for SRM 1598a and anion exchange for SRM 3244 were optimized to achieve the desired separation characteristics without substantially increasing the procedure blank. Sensitivity for the determination of Cd in serum was additionally enhanced through the use of desolvation nebulization. We determined that separations were not required for the accurate ICP-MS determination of Cd in SRM 3240, SRM 3241, SRM 3243, and SRM 966 L2 under optimized analysis conditions. These samples were diluted to a minimum volume and introduced to the ICP-MS via low flow (40-100 microL/min) microconcentric nebulizers. SRM 966 L1 was also analyzed directly, but results were highly variable. The ID-ICP-MS sample preparation and ratio measurement protocols described here resulted in total expanded uncertainties of less

  18. Relationships Between Spiritual Quotient and Marital Satisfaction Level of Men, Women and Couples Referred to Consultancy Centers of Bandar Abbas

    PubMed Central

    Zarei, Eghbal; Ahmadisarkhooni, Tahereh

    2013-01-01

    Objective: The aim of this research is to determine the relationship between Spiritual Quotient parameters including understanding, life origin, and spiritual life and marital satisfaction of couples in Bandar Abbas City. Methods: It is descriptive correlational study. 150 couples referred to consultancy centers of Bandar Abbas City were selected by accessible sampling method. We utilized Spiritual Quotient Questionnaire and Marriage Satisfaction Questionnaire (ENRICH) which both have high reliability and validity levels. We calculated men, women and couples’ scores in the questionnaires. Results: According to the findings; among all parameters of Spiritual Quotient, spiritual life had the strongest correlation with spiritual quotient (r=0.282 and r=0.277 for men and women; P<0.01 for both). Meanwhile, there were not any significant relationship between couples’ understanding and origin of life and their marital satisfaction. Conclusion: Overall, we can conclude that training according to cultural conditions as well as promoting couples’ spiritual quotient can be utilized to improve the quality of marital life of couples.–More studies should be conducted for further evaluation of the relationship between SQ and marital satisfaction. The results can be used for helping couples in increasing their marital satisfaction. Declaration of interest: None PMID:24644499

  19. Evidence of dose saving in routine CT practice using iterative reconstruction derived from a national diagnostic reference level survey

    PubMed Central

    Hayton, A; Beveridge, T; Marks, P; Wallace, A

    2015-01-01

    Objective: To assess the influence and significance of the use of iterative reconstruction (IR) algorithms on patient dose in CT in Australia. Methods: We examined survey data submitted to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) National Diagnostic Reference Level Service (NDRLS) during 2013 and 2014. We compared median survey dose metrics with categorization by scan region and use of IR. Results: The use of IR results in a reduction in volume CT dose index of between 17% and 44% and a reduction in dose–length product of between 14% and 34% depending on the specific scan region. The reduction was highly significant (p < 0.001, Wilcoxon rank-sum test) for all six scan regions included in the NDRLS. Overall, 69% (806/1167) of surveys included in the analysis used IR. Conclusion: The use of IR in CT is achieving dose savings of 20–30% in routine practice in Australia. IR appears to be widely used by participants in the ARPANSA NDRLS with approximately 70% of surveys submitted employing this technique. Advances in knowledge: This study examines the impact of the use of IR on patient dose in CT on a national scale. PMID:26133224

  20. Survey of computed tomography doses and establishment of national diagnostic reference levels in the Republic of Belarus.

    PubMed

    Kharuzhyk, S A; Matskevich, S A; Filjustin, A E; Bogushevich, E V; Ugolkova, S A

    2010-01-01

    Computed tomography dose index (CTDI) was measured on eight CT scanners at seven public hospitals in the Republic of Belarus. The effective dose was calculated using normalised values of effective dose per dose-length product (DLP) over various body regions. Considerable variations of the dose values were observed. Mean effective doses amounted to 1.4 +/- 0.4 mSv for brain, 2.6 +/- 1.0 mSv for neck, 6.9 +/- 2.2 mSv for thorax, 7.0 +/- 2.3 mSv for abdomen and 8.8 +/- 3.2 mSv for pelvis. Diagnostic reference levels (DRLs) were proposed by calculating the third quartiles of dose value distributions (body region/volume CTDI, mGy/DLP, mGy cm): brain/60/730, neck/55/640, thorax/20/500, abdomen/25/600 and pelvis/25/490. It is evident that the protocols need to be optimised on some of the CT scanners, in view of the fact that these are the first formulated DRLs for the Republic of Belarus.

  1. Leveling

    USGS Publications Warehouse

    1966-01-01

    Geodetic leveling by the U.S. Geological Survey provides a framework of accurate elevations for topographic mapping. Elevations are referred to the Sea Level Datum of 1929. Lines of leveling may be run either with automatic or with precise spirit levels, by either the center-wire or the three-wire method. For future use, the surveys are monumented with bench marks, using standard metal tablets or other marking devices. The elevations are adjusted by least squares or other suitable method and are published in lists of control.

  2. Local patient dose diagnostic reference levels in pediatric interventional cardiology in Chile using age bands and patient weight values

    SciTech Connect

    Ubeda, Carlos; Miranda, Patricia; Vano, Eliseo

    2015-02-15

    Purpose: To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency. Methods: Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs. Results: Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for <1 yr; 213 for 1 to <5 yr; 82 for 5 to <10 yr; and 102 for 10 to <16 yr. The third quartile values obtained for DAP by diagnostic and therapeutic procedures and age range were 1.17 and 1.11 Gy cm{sup 2} for <1 yr; 1.74 and 1.90 Gy cm{sup 2} for 1 to <5 yr; 2.83 and 3.22 Gy cm{sup 2} for 5 to <10 yr; and 7.34 and 8.68 Gy cm{sup 2} for 10 to <16 yr, respectively. The third quartile value obtained for the DAP/body weight ratio for the full sample of procedures was 0.17 (Gy cm{sup 2}/kg) for diagnostic and therapeutic procedures. Conclusions: The data presented in this paper are an initial attempt at establishing local DRLs in pediatric interventional cardiology, from a large sample of procedures for the standard age bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there

  3. Development of a chronic noncancer oral reference dose and drinking water screening level for sulfolane using benchmark dose modeling.

    PubMed

    Thompson, Chad M; Gaylor, David W; Tachovsky, J Andrew; Perry, Camarie; Carakostas, Michael C; Haws, Laurie C

    2013-12-01

    Sulfolane is a widely used industrial solvent that is often used for gas treatment (sour gas sweetening; hydrogen sulfide removal from shale and coal processes, etc.), and in the manufacture of polymers and electronics, and may be found in pharmaceuticals as a residual solvent used in the manufacturing processes. Sulfolane is considered a high production volume chemical with worldwide production around 18 000-36 000 tons per year. Given that sulfolane has been detected as a contaminant in groundwater, an important potential route of exposure is tap water ingestion. Because there are currently no federal drinking water standards for sulfolane in the USA, we developed a noncancer oral reference dose (RfD) based on benchmark dose modeling, as well as a tap water screening value that is protective of ingestion. Review of the available literature suggests that sulfolane is not likely to be mutagenic, clastogenic or carcinogenic, or pose reproductive or developmental health risks except perhaps at very high exposure concentrations. RfD values derived using benchmark dose modeling were 0.01-0.04 mg kg(-1) per day, although modeling of developmental endpoints resulted in higher values, approximately 0.4 mg kg(-1) per day. The lowest, most conservative, RfD of 0.01 mg kg(-1) per day was based on reduced white blood cell counts in female rats. This RfD was used to develop a tap water screening level that is protective of ingestion, viz. 365 µg l(-1). It is anticipated that these values, along with the hazard identification and dose-response modeling described herein, should be informative for risk assessors and regulators interested in setting health-protective drinking water guideline values for sulfolane.

  4. Characteristics of the Remote Sensing Data Used in the Proposed Unfccc REDD+ Forest Reference Emission Levels (frels)

    NASA Astrophysics Data System (ADS)

    Johnson, B. A.; Scheyvens, H.; Samejima, H.; Onoda, M.

    2016-06-01

    Developing countries must submit forest reference emission levels (FRELs) to the UNFCCC to receive incentives for REDD+ activities (e.g. reducing emissions from deforestation/forest degradation, sustainable management of forests, forest carbon stock conservation/enhancement). These FRELs are generated based on historical CO2 emissions in the land use, land use change, and forestry sector, and are derived using remote sensing (RS) data and in-situ forest carbon measurements. Since the quality of the historical emissions estimates is affected by the quality and quantity of the RS data used, in this study we calculated five metrics (i-v below) to assess the quality and quantity of the data that has been used thus far. Countries could focus on improving on one or more of these metrics for the submission of future FRELs. Some of our main findings were: (i) the median percentage of each country mapped was 100%, (ii) the median historical timeframe for which RS data was used was 11.5 years, (iii) the median interval of forest map updates was 4.5 years, (iv) the median spatial resolution of the RS data was 30m, and (v) the median number of REDD+ activities that RS data was used for operational monitoring of was 1 (typically deforestation). Many new sources of RS data have become available in recent years, so complementary or alternative RS data sets for generating future FRELs can potentially be identified based on our findings; e.g. alternative RS data sets could be considered if they have similar or higher quality/quantity than the currently-used data sets.

  5. SU-F-207-14: Low Contrast Detectability (LCD) at Different Diagnostic Reference Levels for Adult Abdominal CT Procedures

    SciTech Connect

    Mahmood, U; Erdi, Y

    2015-06-15

    Purpose Using diagnostic reference levels (DRL) to optimize CT protocols has potential to reduce radiation dose and meet regulatory requirements. However, DRL’s tend to be misconstrued as dose limits, are typically designed for specific patient populations, and are assumed to have acceptable image quality (AIQ) associated with them. To determine the image quality that is associated with established DRL’s for adult abdominal CT studies, a LCD phantom study was employed. Methods: A CT phantom (CIRS) containing three columns of 7 spherical targets, ranging from 10mm to 2.4 mm, that are 5, 10, and 20 HU below the background (HUBB) matrix was scanned with a GE HD750 64 slice scanner. The phantom was scanned at the NEXT 2006 25th CTDIvol of 12 mGy, the NCRP 172 achievable dose (AD) CTDIvol of 17 mGy and 75th CTDIvol of 25 mGy and at the ACR recommended CTDIvol of 25 mGy. It was also scanned at a CTDIvol 20% greater than the AD at 20 mGy and the ACR maximum threshold of 30 mGy. Results: At the NEXT 2006 25th percentile CTDIvol of 12 mGy, a 6.3 mm low contrast lesion was detectable in the 20 HUBB; 6.3 mm in the 10 HUBB and 10 mm in the 5 HUBB column. Increasing the CTDIvol to the NCRP 172 AD of 17 mGy, an additional 4.8 mm lesion was visualized in the 20 HUBB column. At 20 mGy, an additional 4.8 mm lesion was detectable in the 10 HUBB column. No further lesions were visible between 20 and 30 mGy. However, conspicuity of all lesions increased with each additional step up in CTDI. Conclusion: Optimizing radiation dose to achieve AIQ is a critical aspect of any dose optimization committee. Hence, judicious monitoring of radiation exposure to patients has to be balanced with diagnostic image quality.

  6. Fabrication and qualification of roughness reference samples for industrial testing of surface roughness levels below 0.5 nm Sq

    NASA Astrophysics Data System (ADS)

    Faehnle, O.; Langenbach, E.; Zygalsky, F.; Frost, F.; Fechner, R.; Schindler, A.; Cumme, M.; Biskup, H.; Wünsche, C.; Rascher, R.

    2015-08-01

    Applying reactive ion beam etching (RIBE) processes at the Leibniz Institute of Surface Modification (IOM), several reference samples to be used in industry for calibrating of roughness testing equipment have been generated with the smoothest sample featuring 0.1 nm rms Sq. Subsequently these reference samples have been measured cross-site applying atomic force microscopy (AFM), white light interferometry (WLI), Nomarski1 microscopy (NM) and scatterometry (iTIRM2) determining the appropriate range of measurable rms surface roughness for each industrial measuring device.

  7. Age- and Gender-Specific Reference Intervals for Fasting Blood Glucose and Lipid Levels in School Children Measured With Abbott Architect c8000 Chemistry Analyzer.

    PubMed

    Tamimi, Waleed; Albanyan, Esam; Altwaijri, Yasmin; Tamim, Hani; Alhussein, Fahad

    2012-04-01

    Reference intervals for pubertal characteristics are influenced by genetic, geographic, dietary and socioeconomic factors. Therefore, the aim of this study was to establish age-specific reference intervals of glucose and lipid levels among local school children. This was cross-sectional study, conducted among Saudi school children. Fasting blood samples were collected from 2149 children, 1138 (53%) boys and 1011 (47%) girls, aged 6 to 18 years old. Samples were analyzed on the Architect c8000 Chemistry System (Abbott Diagnostics, USA) for glucose, cholesterol, triglycerides, HDL and LDL. Reference intervals were established by nonparametric methods between the 2.5th and 97.5th percentiles. Significant differences were observed between boys and girls for cholesterol and triglycerides levels in all age groups (P < 0.02). Only at age 6-7 years and at adolescents, HDL and LDL levels were found to be significant (P < 0.001). No significant differences were seen in glucose levels except at age 12 to 13 years. Saudi children have comparable serum cholesterol levels than their Western counterparts. This may reflect changing dietary habits and increasing affluence in Saudi Arabia. Increased lipid screening is anticipated, and these reference intervals will aid in the early assessment of cardiovascular and diabetes risk in Saudi pediatric populations.

  8. An Analysis of HIV and AIDS Spatial Awareness and Vulnerability Level with Specific Reference to Staff at One Polytechnic in Zimbabwe

    ERIC Educational Resources Information Center

    Gatsi, Caroline; Chikuvadze, Pinias; Mugijima, Samuel

    2016-01-01

    With the gravity of the HIV and AIDS situation in most African nations and its implications for the education sector, a study was undertaken to analyze the spatial awareness and vulnerability level to pandemic in tertiary institutions with specific reference to academic and support staff at one polytechnic in Zimbabwe. A sample comprised of…

  9. Intercomparison of ultraviolet photometry and gas-phase titration techniques for ozone reference standards at ambient levels

    NASA Astrophysics Data System (ADS)

    Tanimoto, Hiroshi; Mukai, Hitoshi; Hashimoto, Shigeru; Norris, James E.

    2006-08-01

    Intercomparison experiments were made between two independent techniques for ozone (O3) reference standards often used as the primary standards in air quality monitoring networks. These techniques include ultraviolet absorption photometry of O3 at the 253.7-nm Hg line and gas-phase titration of O3 with excess NO. For ultraviolet photometry, a well-designed and maintained standard reference photometer (SRP) built by the National Institute of Standards and Technology (USA) was employed. For gas-phase titration (GPT), an existing system was significantly modified by the National Institute for Environmental Studies (Japan) by using gravimetric NO/N2 standard gases, accurate flow measurement systems based on laminar flow elements, and two chemiluminescence NO detectors to minimize uncertainty in the measurements, which had previously been a major shortcoming of this method. Uncertainty in the improved GPT system was reduced to less than 0.4% above 100 nmol mol-1 O3 mole fraction. A series of comparison runs between the two methods over the course of 13 months from August 2004 to August 2005 showed a significant discrepancy, which cannot be explained by the measurement uncertainties attributed to either SRP or GPT in the range of 80-800 nmol mol-1 O3, where GPT was about 2% higher than SRP. This result indicates possible biases in the currently existing O3 reference standards and warrants further studies to identify and characterize possible sources of the systematic discrepancy.

  10. Reference values of cadmium, arsenic and manganese in blood and factors associated with exposure levels among adult population of Rio Branco, Acre, Brazil.

    PubMed

    Freire, Carmen; Koifman, Rosalina Jorge; Fujimoto, Denys; de Oliveira Souza, Vanessa Cristina; Barbosa, Fernando; Koifman, Sergio

    2015-06-01

    This study aimed to investigate the distribution and factors influencing blood levels of Cadmium (Cd), Arsenic (As), and Manganese (Mn), and to determine their reference values in a sample of blood donors residing in Rio Branco, capital city of Acre State, Brazil. Blood samples were collected from all blood donors attending the Central Hemotherapic Unit in Rio Branco between 2010 and 2011. Among these, 1183 donors (98.9%) answered to a questionnaire on sociodemographic and lifestyle factors. Blood metal concentrations were determined by atomic spectrometry. Association between Cd, As and Mn levels and donors' characteristics was examined by linear regression analysis. Reference values were estimated as the upper limit of the 95% confidence interval of the 95th percentile of metal levels. References values were 0.87 μg L(-1) for Cd, 9.87 μg L(-1) for As, and 29.32 μg L(-1) for Mn. Reference values of Cd and As in smokers were 2.66 and 10.86 μg L(-1), respectively. Factors contributing to increase Cd levels were smoking, ethnicity (non-white), and lower education, whereas drinking tea and non-bottled water were associated with lower Cd. Lower levels of As were associated with higher household income, living near industrial facilities, working in a glass factory, a compost plant or in metal mining activities. Risk factors for Mn exposure were not identified. In general, blood Cd concentrations were in the range of exposure levels reported for other people from the general population, whereas levels of As and Mn were higher than in other non-occupationally exposed populations elsewhere.

  11. Comparison of blood volatile organic compound levels in residents of Calcasieu and Lafayette Parishes, LA, with US reference ranges.

    PubMed

    Uddin, Mohammed S; Blount, Benjamin C; Lewin, Michael D; Potula, Vijayalakshmi; Ragin, Angela D; Dearwent, Steve M

    2014-11-01

    Agency for Toxic Substances and Disease Registry conducted a study to evaluate body burden levels of volatile organic compounds (VOCs) among residents of highly industrialized Calcasieu Parish, LA, USA, in 2002. Blood VOC levels in a representative sample of participants in Calcasieu Parish were compared with a similar group of participants in the less-industrialized Lafayette Parish. Participants' ages ranged from 15 to 91 years, 46% were men, and 89% were Caucasian. VOC levels in these two populations were also compared at the national levels. Solid-phase microextraction coupled with gas chromatography mass spectrometry was used to measure levels of 30 VOCs in blood samples collected from 283 self-described non-smoking study participants. Of the 30 VOCs, 6 had quantifiable levels in at least 25% of the blood samples analyzed. The frequency of detection was >95% for benzene and m-/p-xylene, >60% for 1,4-dichlorbenzene and toluene, 27% for ethylbenzene, and 39% for styrene. Calcasieu and Lafayette Parish participants had similar distributions for six VOCs in key percentiles and geometric means. When compared with a representative sampling of the 1999-2000 US general population, no significant differences were found between the parish data and the US general population.

  12. Relevance of biotic pathways to the long-term regulation of nuclear-waste disposal. Topical report on reference western arid low-level sites

    SciTech Connect

    McKenzie, D.H.; Cadwell, L.L.; Eberhardt, L.E.; Kennedy, W.E. Jr.; Peloquin, R.A.; Simmons, M.A.

    1982-10-01

    The purpose of the work reported here was to develop an order of magnitude estimate for the potential dose to man resulting from biotic transport mechanisms at a reference western arid low-level waste site. A description of the reference site is presented that includes the waste inventories, site characteristics and biological communities. Parameter values for biotic transport processes are based on data reported in current literature. Transport and exposure scenarios are developed for assessing biotic transport during 100 years following site closure. Calculations of radionuclide decay and waste container decomposition are made to estimate the quantities available for biotic transport. Dose to a man occupying the reference site following the 100 years of biotic transport are calculated. These dose estimates are compared to dose estimates for the intruder-agricultural scenario reported in the DEIS for 10 CFR 61 (NRC). Dose to man estimates as a result of biotic transport are estimated to be of the same order of magnitude as the dose resulting from the more commonly evaluated human intrusion scenario. The reported lack of potential importance of biotic transport at low-level waste sites in earlier assessment studies is not confirmed by the findings presented in this report. These results indicate that biotic transport has the potential to influence low-level waste site performance. Through biotic transport, radionuclides may be moved to locations where they can enter exposure pathways to man.

  13. Validation of RT-qPCR reference genes and determination of Robo4 expression levels in human retinal endothelial cells under hypoxia and/or hyperglycemia.

    PubMed

    Xie, Jia'nan; Liu, Xin; Li, Ying; Liu, Yang; Su, Guanfang

    2016-07-01

    Real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) has become the most common technique to investigate mRNA expression levels of target genes. In order to obtain accurate results, stable reference genes need to be selected for normalization in an experimental study. Human retinal endothelial cells (HREC) cultured in a hypoxic and hyperglycemic environment is a potential cell model to study diabetic retinopathy (DR), but the proper reference genes for RNA analysis have not yet been determined. In the present study, we evaluated the expression levels of 14 candidate housekeeping genes and selected the most suitable reference genes for RT-qPCR for HREC under hypoxic and/or hyperglycemic conditions. The results of the analyses using GeNorm, NormFinder, and BestKeeper software showed that a combination of TBP, PUM1, and ALAS1 was most suitable for this research. Based on these results, mRNA expression levels of Roundabout4 (Robo4) in HREC were determined. The RT-qPCR analysis showed that there was a significant increase in Robo4 expression under hyperglycemic conditions, while there was a decrease in expression under hypoxic and combined hypoxic and hyperglycemic conditions, suggesting that Robo4 might play different roles in various stages of DR.

  14. Radiostrontium levels in foodstuffs: 4-Years control activity by Italian reference centre, as a contribution to risk assessment.

    PubMed

    Iammarino, Marco; dell'Oro, Daniela; Bortone, Nicola; Mangiacotti, Michele; Damiano, Rita; Chiaravalle, Antonio Eugenio

    2016-11-01

    (90)Sr is considered an important contaminant relating to food supply chains. In this study, 176 liquid and 260 solid foods, were analysed in order to quantify (90)Sr. Through ruggedness tests, the application field of radiochemical methods used was extended successfully to all most important types of foodstuffs. Regarding liquid matrices, milk samples resulted the most important indicator about (90)Sr contamination, with mean (90)Sr activity concentration equal to 0.058BqL(-1). Among other liquid foods, wine/spirits and livestock watering resulted the most contaminated, with mean contamination levels equal to 0.022 and 0.035BqL(-1), respectively. Concerning solid matrices, cheeses produced from sheep's milk and animal feeds resulted the most contaminated (mean levels: 1.237 and 1.557Bqkg(-1), respectively). Meat products and seafood showed contamination levels not significant within this survey; while, among vegetables, cacao/chocolate and spices resulted in contamination levels comparable with those of cheese obtained from milk of cows origin.

  15. Age and gender-related reference values for serum dl-alpha-tocopherol and all-trans-retinol levels in Saudi population.

    PubMed

    Al-Saleh, Iman; El-Doush, Inaam; Billedo, Grisellhi

    2007-09-01

    We established a reference range for dl-alpha-tocopherol and all-trans-retinol in a Saudi population previously selected for a cross-sectional study evaluating selenium and vitamin status. Concentrations of dl-alpha-tocopherol and all-trans-retinol were 0.999 +/- 0.31 mg/dL (n=994, range 0.11-3.42 mg/dL) and 49.14 +/- 24.15 micro/dL (n=1000, range 11.20-400.85 microg/dL), respectively. The levels of dl-alpha-tocopherol and all-trans-retinol in serum were determined by high-pressure liquid chromatography (HPLC) equipped with a UV detector. We took the influence of age and gender into account. Both had significant effect on the levels of all-trans-retinol in serum, except in the case of dl-alpha-tocopherol, where no gender related effect was found. We used the 5th and 95th percentiles as reference limits. Based on these criteria, it was found that these reference limits differed between genders for all-trans-retinol. Our lower and upper limits for dl-alpha-tocopherol classified by three age groups were very close to the normal range of 0.5-1.6 mg/dL, as found in previous studies. The 5th percentile of all-trans-retinol in both males and females, stratified by age, was close to a level of <20 microg/dL, which could be regarded as a mild vitamin A deficiency according to WHO criteria. But the value corresponding to the 95th percentile was higher than the upper limit of vitamin A's normal range of 70 microg/dL, suggesting a potentially harmful high dietary intake of vitamin A. The reference intervals elaborated here may help in the assessment of the vitamin status and in detecting subjects at risk of developing pathologies associated with either excess intake or deficiency.

  16. Combination of Vlbi, GPS and Slr Observations At The Observation Level For The Realization of Terrestrial and Celestial Reference Frames

    NASA Astrophysics Data System (ADS)

    Andersen, P. H.

    Forsvarets forskningsinstitutt (FFI, the Norwegian Defence Research Establishment) has during the last 17 years developed a software system called GEOSAT, for the analysis of any type of high precision space geodetic observations. A unique feature of GEOSAT is the possibility of combining any combination of different space geode- tic data at the observation level with one consistent model and one consistent strategy. This is a much better strategy than the strategy in use today where different types of observations are processed separately using analysis software developed specifically for each technique. The results from each technique are finally combined a posteriori. In practice the models implemented in the software packages differ at the 1-cm level which is almost one order of magnitude larger than the internal precision of the most precise techniques. Another advantage of the new proposed combination method is that for example VLBI and GPS can use the same tropospheric model with common parameterization. The same is the case for the Earth orientation parameters, the geo- center coordinates and other geodetic or geophysical parameters where VLBI, GPS and SLR can have a common estimate for each of the parameters. The analysis with GEOSAT is automated for the combination of VLBI, SLR and GPS observations. The data are analyzed in batches of one day where the result from each daily arc is a SRIF array (Square Root Information Filter). A large number of SRIF arrays can be combined into a multi-year solution using the CSRIFS program (Com- bination Square Root Information Filter and Smoother). Four parameter levels are available and any parameter can, at each level, either be represented as a constant or a stochastic parameter (white noise, colored noise, or random walk). The batch length (i.e. the time interval between the addition of noise to the SRIF array) can be made time- and parameter dependent. GEOSAT and CSRIFS have been applied in the analysis of selected

  17. A review of trend models applied to sea level data with reference to the "acceleration-deceleration debate"

    NASA Astrophysics Data System (ADS)

    Visser, Hans; Dangendorf, Sönke; Petersen, Arthur C.

    2015-06-01

    Global sea levels have been rising through the past century and are projected to rise at an accelerated rate throughout the 21st century. This has motivated a number of authors to search for already existing accelerations in observations, which would be, if present, vital for coastal protection planning purposes. No scientific consensus has been reached yet as to how a possible acceleration could be separated from intrinsic climate variability in sea level records. This has led to an intensive debate on its existence and, if absent, also on the general validity of current future projections. Here we shed light on the controversial discussion from a methodological point of view. To do so, we provide a comprehensive review of trend methods used in the community so far. This resulted in an overview of 30 methods, each having its individual mathematical formulation, flexibilities, and characteristics. We illustrate that varying trend approaches may lead to contradictory acceleration-deceleration inferences. As for statistics-oriented trend methods, we argue that checks on model assumptions and model selection techniques yield a way out. However, since these selection methods all have implicit assumptions, we show that good modeling practices are of importance too. We conclude at this point that (i) several differently characterized methods should be applied and discussed simultaneously, (ii) uncertainties should be taken into account to prevent biased or wrong conclusions, and (iii) removing internally generated climate variability by incorporating atmospheric or oceanographic information helps to uncover externally forced climate change signals.

  18. GLM Proxy Data Generation: Methods for Stroke/Pulse Level Inter-Comparison of Ground-Based Lightning Reference Networks

    NASA Technical Reports Server (NTRS)

    Cummins, Kenneth L.; Carey, Lawrence D.; Schultz, Christopher J.; Bateman, Monte G.; Cecil, Daniel J.; Rudlosky, Scott D.; Petersen, Walter Arthur; Blakeslee, Richard J.; Goodman, Steven J.

    2011-01-01

    In order to produce useful proxy data for the GOES-R Geostationary Lightning Mapper (GLM) in regions not covered by VLF lightning mapping systems, we intend to employ data produced by ground-based (regional or global) VLF/LF lightning detection networks. Before using these data in GLM Risk Reduction tasks, it is necessary to have a quantitative understanding of the performance of these networks, in terms of CG flash/stroke DE, cloud flash/pulse DE, location accuracy, and CLD/CG classification error. This information is being obtained through inter-comparison with LMAs and well-quantified VLF/LF lightning networks. One of our approaches is to compare "bulk" counting statistics on the spatial scale of convective cells, in order to both quantify relative performance and observe variations in cell-based temporal trends provided by each network. In addition, we are using microsecond-level stroke/pulse time correlation to facilitate detailed inter-comparisons at a more-fundamental level. The current development status of our ground-based inter-comparison and evaluation tools will be presented, and performance metrics will be discussed through a comparison of Vaisala s Global Lightning Dataset (GLD360) with the NLDN at locations within and outside the U.S.

  19. Reference design of 100 MW-h lithium/iron sulfide battery system for utility load leveling

    SciTech Connect

    Zivi, S.M.; Kacinskas, H.; Pollack, I.; Chilenskas, A.A.; Barney, D.L.; Grieve, W.; McFarland, B.L.; Sudar, S.; Goldstein, E.; Adler, E.

    1980-03-01

    The first year in a two-year cooperative effort between Argonne National Laboratory and Rockwell International to develop a conceptual design of a lithium alloy/iron sulfide battery for utility load leveling is presented. A conceptual design was developed for a 100 MW-h battery system based upon a parallel-series arrangement of 2.5 kW-h capacity cells. The sales price of such a battery system was estimated to be very high, $80.25/kW-h, exclusive of the cost of the individual cells, the dc-to-ac converters, site preparation, or land acquisition costs. Consequently, the second year's efforts were directed towards developing modified designs with significantly lower potential costs.

  20. Significant RF-EMF and thermal levels observed in a computational model of a person with a tibial plate for grounded 40 MHz exposure.

    PubMed

    McIntosh, Robert L; Iskra, Steve; Anderson, Vitas

    2014-05-01

    Using numerical modeling, a worst-case scenario is considered when a person with a metallic implant is exposed to a radiofrequency (RF) electromagnetic field (EMF). An adult male standing on a conductive ground plane was exposed to a 40 MHz vertically polarized plane wave field, close to whole-body resonance where maximal induced current flows are expected in the legs. A metal plate (50-300 mm long) was attached to the tibia in the left leg. The findings from this study re-emphasize the need to ensure compliance with limb current reference levels for exposures near whole-body resonance, and not just rely on compliance with ambient electric (E) and magnetic (H) field reference levels. Moreover, we emphasize this recommendation for someone with a tibial plate, as failure to comply may result in significant tissue damage (increases in the localized temperature of 5-10 °C were suggested by the modeling for an incident E-field of 61.4 V/m root mean square (rms)). It was determined that the occupational reference level for limb current (100 mA rms), as stipulated in the 1998 guidelines of the International Commission on Non-Ionizing Radiation Protection (ICNIRP), is satisfied if the plane wave incident E-field levels are no more than 29.8 V/m rms without an implant and 23.4 V/m rms for the model with a 300 mm implant.

  1. Repeated Acceleration Ability (RAA): A New Concept with Reference to Top-Level Field and Assistant Soccer Referees

    PubMed Central

    Barberó-Álvarez, José Carlos; Boullosa, Daniel; Nakamura, Fábio Yuzo; Andrín, Germán; Weston, Matthew

    2013-01-01

    Purpose To perform an exploratory characterization of repeated sprint sequences (RSS) and repeated acceleration sequences (RAS) in top level soccer referees. Methods 7 field and 7 assistant referees were monitored during 2007 America's Soccer Cup with GPS technology. Sprints of >18 km·h-1 and accelerations of >1.5 m·s-2 were considered as high intensity activities. RSS and RAS were defined as a minimum of 3 consecutive bouts interspersed with a maximum of 45 s. Results Field and assistant referees performed substantially more accelerations than sprints. Neither field nor assistant referees recorded any RSS. In contrast, total distance performing RAS amounted to ∼37% and ∼20% of the total distance covered by accelerations during the entire match for field and assistant referees, respectively. Only field referees exhibited fatigue-related reductions in RAS characteristics between halves. Conclusion The results of the present study would appear to support the appropriateness of a repeated acceleration ability (RAA) concept, instead of the repeated sprint ability (RSA) concept, in soccer referees. Further studies should assess RAS in referees and athletes of different team sports for designing better training exercises and physiological testing. PMID:24868433

  2. An energy decomposition analysis for intermolecular interactions from an absolutely localized molecular orbital reference at the coupled-cluster singles and doubles level

    SciTech Connect

    Azar, R. Julian; Head-Gordon, Martin

    2012-01-14

    We propose a wave function-based method for the decomposition of intermolecular interaction energies into chemically-intuitive components, isolating both mean-field- and explicit correlation-level contributions. We begin by solving the locally-projected self-consistent field for molecular interactions equations for a molecular complex, obtaining an intramolecularly polarized reference of self-consistently optimized, absolutely-localized molecular orbitals (ALMOs), determined with the constraint that each fragment MO be composed only of atomic basis functions belonging to its own fragment. As explicit inter-electronic correlation is integral to an accurate description of weak forces underlying intermolecular interaction potentials, namely, coordinated fluctuations in weakly interacting electronic densities, we add dynamical correlation to the ALMO polarized reference at the coupled-cluster singles and doubles level, accounting for explicit dispersion and charge-transfer effects, which map naturally onto the cluster operator. We demonstrate the stability of energy components with basis set extension, follow the hydrogen bond-breaking coordinate in the C{sub s}-symmetry water dimer, decompose the interaction energies of dispersion-bound rare gas dimers and other van der Waals complexes, and examine charge transfer-dominated donor-acceptor interactions in borane adducts. We compare our results with high-level calculations and experiment when possible.

  3. An energy decomposition analysis for intermolecular interactions from an absolutely localized molecular orbital reference at the coupled-cluster singles and doubles level.

    PubMed

    Azar, R Julian; Head-Gordon, Martin

    2012-01-14

    We propose a wave function-based method for the decomposition of intermolecular interaction energies into chemically-intuitive components, isolating both mean-field- and explicit correlation-level contributions. We begin by solving the locally-projected self-consistent field for molecular interactions equations for a molecular complex, obtaining an intramolecularly polarized reference of self-consistently optimized, absolutely-localized molecular orbitals (ALMOs), determined with the constraint that each fragment MO be composed only of atomic basis functions belonging to its own fragment. As explicit inter-electronic correlation is integral to an accurate description of weak forces underlying intermolecular interaction potentials, namely, coordinated fluctuations in weakly interacting electronic densities, we add dynamical correlation to the ALMO polarized reference at the coupled-cluster singles and doubles level, accounting for explicit dispersion and charge-transfer effects, which map naturally onto the cluster operator. We demonstrate the stability of energy components with basis set extension, follow the hydrogen bond-breaking coordinate in the C(s)-symmetry water dimer, decompose the interaction energies of dispersion-bound rare gas dimers and other van der Waals complexes, and examine charge transfer-dominated donor-acceptor interactions in borane adducts. We compare our results with high-level calculations and experiment when possible.

  4. An energy decomposition analysis for intermolecular interactions from an absolutely localized molecular orbital reference at the coupled-cluster singles and doubles level

    NASA Astrophysics Data System (ADS)

    Azar, R. Julian; Head-Gordon, Martin

    2012-01-01

    We propose a wave function-based method for the decomposition of intermolecular interaction energies into chemically-intuitive components, isolating both mean-field- and explicit correlation-level contributions. We begin by solving the locally-projected self-consistent field for molecular interactions equations for a molecular complex, obtaining an intramolecularly polarized reference of self-consistently optimized, absolutely-localized molecular orbitals (ALMOs), determined with the constraint that each fragment MO be composed only of atomic basis functions belonging to its own fragment. As explicit inter-electronic correlation is integral to an accurate description of weak forces underlying intermolecular interaction potentials, namely, coordinated fluctuations in weakly interacting electronic densities, we add dynamical correlation to the ALMO polarized reference at the coupled-cluster singles and doubles level, accounting for explicit dispersion and charge-transfer effects, which map naturally onto the cluster operator. We demonstrate the stability of energy components with basis set extension, follow the hydrogen bond-breaking coordinate in the Cs-symmetry water dimer, decompose the interaction energies of dispersion-bound rare gas dimers and other van der Waals complexes, and examine charge transfer-dominated donor-acceptor interactions in borane adducts. We compare our results with high-level calculations and experiment when possible.

  5. Validation of the Australian diagnostic reference levels for paediatric multi detector computed tomography: a comparison of RANZCR QUDI data and subsequent NDRLS data from 2012 to 2015.

    PubMed

    Anna, Hayton; Wallace, Anthony; Thomas, Peter

    2017-03-01

    The national diagnostic reference level service (NDRLS), was launched in 2011, however no paediatric data were submitted during the first calendar year of operation. As such, Australian national diagnostic reference levels (DRLs), for paediatric multi detector computed tomography (MDCT), were established using data obtained from a Royal Australian and New Zealand College of Radiologists (RANZCR), Quality Use of Diagnostic Imaging (QUDI), study. Paediatric data were submitted to the NDRLS in 2012 through 2015. An analysis has been made of the NDRLS paediatric data using the same method as was used to analyse the QUDI data to establish the Australian national paediatric DRLs for MDCT. An analysis of the paediatric NDRLS data has also been made using the method used to calculate the Australian national adult DRLs for MDCT. A comparison between the QUDI data and subsequent NDRLS data shows the NDRLS data to be lower on average for the Head and AbdoPelvis protocol and similar for the chest protocol. Using an average of NDRLS data submitted between 2012 and 2015 implications for updated paediatric DRLS are considered.

  6. Comparison of species-level identification and antifungal susceptibility results from diagnostic and reference laboratories for bloodstream Candida surveillance isolates, South Africa, 2009-2010.

    PubMed

    Naicker, Serisha D; Govender, Nevashan; Patel, Jaymati; Zietsman, Inge L; Wadula, Jeannette; Coovadia, Yacoob; Kularatne, Ranmini; Seetharam, Sharona; Govender, Nelesh P

    2016-11-01

    From February 2009 through August 2010, we compared species-level identification of bloodstream Candida isolates and susceptibility to fluconazole, voriconazole, and caspofungin between diagnostic and reference South African laboratories during national surveillance for candidemia. Diagnostic laboratories identified isolates to genus/species level and performed antifungal susceptibility testing, as indicated. At a reference laboratory, viable Candida isolates were identified to species-level using automated systems, biochemical tests, or DNA sequencing; broth dilution susceptibility testing was performed. Categorical agreement (CA) was calculated for susceptibility results of isolates with concordant species identification. Overall, 2172 incident cases were detected, 773 (36%) by surveillance audit. The Vitek 2 YST system (bioMérieux Inc, Marcy l'Etoile, France) was used for identification (360/863, 42%) and susceptibility testing (198/473, 42%) of a large proportion of isolates. For the five most common species (n = 1181), species-level identification was identical in the majority of cases (Candida albicans: 98% (507/517); Candida parapsilosis: 92% (450/488); Candida glabrata: 89% (89/100); Candida tropicalis: 91% (49/54), and Candida krusei: 86% (19/22)). However, diagnostic laboratories were significantly less likely to correctly identify Candida species other than C. albicans versus C. albicans (607/664, 91% vs. 507/517, 98%; P < .001). Susceptibility data were compared for isolates belonging to the five most common species and fluconazole, voriconazole, and caspofungin in 860, 580, and 99 cases, respectively. Diagnostic laboratories significantly under-reported fluconazole resistance in C. parapsilosis (225/393, 57% vs. 239/393, 61%; P < .001) but over-reported fluconazole non-susceptibility in C. albicans (36/362, 10% vs. 3/362, 0.8%; P < .001). Diagnostic laboratories were less likely to correctly identify Candida species other than C. albicans, under

  7. Reach for Reference. Four Recent Reference Books

    ERIC Educational Resources Information Center

    Safford, Barbara Ripp

    2004-01-01

    This article provides descriptions of four new science and technology encyclopedias that are appropriate for inclusion in upper elementary and/or middle school reference collections. "The Macmillan Encyclopedia of Weather" (Stern, Macmillan Reference/Gale), a one-volume encyclopedia for upper elementary and middle level students, is a…

  8. Change in serum TSH levels within the reference range was associated with variation of future blood pressure: a 5-year follow-up study.

    PubMed

    Jiang, F; Liu, A; Lai, Y; Yu, X; Li, C; Han, C; Zhang, Y; Wang, X; Wang, Z; Bao, S; Lv, N; Jin, M; Yang, F; Fan, Y; Jin, T; Zhao, W; Shan, Z; Teng, W

    2017-04-01

    Controversy exists on the relationship between serum thyrotropin (TSH) and blood pressure, and only a few prospective studies are available up to now. The study aimed to investigate the association between serum TSH within the reference range and blood pressure through a 5-year follow-up study. A total of 623 subjects with normal TSH were followed up for 5 years, including the measurement of demographic data, blood pressure, height, weight and serum TSH. Finally, 531 subjects were included in this prospective study. Body mass index (BMI), prevalence of hypertension, and systolic and diastolic blood pressure were all higher at follow-up than at baseline. Adjusted for age, gender, smoking status, BMI and homoeostasis model assessment of insulin resistance (HOMA-IR) at baseline, multiple linear regression analyses found no relationship between serum TSH at baseline and levels of blood pressure at follow-up, but the changes in serum TSH levels during follow-up was positively associated with the changes in systolic blood pressure (B=2.134, P<0.05), which became more significant in women but not significant in men. The change of systolic blood pressure in group of TSH increase >0.5 mIU l(-1) was significantly higher than in group of TSH decrease >0.5 mIU l(-1) within reference, after adjusting for age, gender, smoking status, BMI and HOMA-IR at baseline. This result became more significant in women, but no statistical significance was observed in men. Co-variation with serum TSH levels and blood pressure was observed during 5-year follow-up among people with normal TSH.

  9. Associated factors for higher lead and cadmium blood levels, and reference values derived from general population of São Paulo, Brazil.

    PubMed

    Kira, Carmen Silvia; Sakuma, Alice Momoyo; De Capitani, Eduardo Mello; de Freitas, Clarice Umbelino; Cardoso, Maria Regina Alves; Gouveia, Nelson

    2016-02-01

    Human activities are associated with emissions of various metals into the environment, among which the heavy metals lead and cadmium stand out, as they pose a risk to human life even at low concentrations. Thus, accurate knowledge of the levels of these metals exhibited by the overall population, including children, is important. The aim of this study was to estimate the concentrations of lead and cadmium in the blood of adults, adolescents and children residing in the city of São Paulo, assess factors associated with higher lead and cadmium blood levels, and to establish reference values for this population. The study sample consisted of 669 adults over 20 years old, 264 adolescents aged 12 to 19 years old and 391 children under 11 years old from both genders. The samples were collected at the end of 2007 and during 2008 in different city zones. Higher blood lead concentration was significantly associated with gender, smoking, offal intake, area of residence and age. The blood cadmium concentration was significantly associated with gender, smoking, consumption of distilled beverages and age. The reference values of lead and cadmium established for adults above 20 years old were 33 μg/L and 0.6 μg/L, respectively, for adolescents (12 to 19 years old) were 31 μg/L and 0.6 μg/L, respectively and for children under 11 years old were 29 μg/L and 0.2 μg/L, respectively. The results of this study indicate that the exposure levels of the investigated population to lead and cadmium are low.

  10. A comparison of levels of bat flight and foraging activity at 10 meters and 30 meters above drained Carolina bays and reference bays, prior to bay restoration.

    SciTech Connect

    Menzel, Michael, A.; Ford, W., Mark; Edwards, John, W.; Kilgo, John, C.

    2001-08-01

    A technical report of a monitoring study of bat flight and foraging activity above drained and undrained Carolina bays at the Savannah River Site (SRS), located near Aiken, South Carolina. In order to determine if the vegetational community type or structure of the forest community surrounding the bays affected bat activity levels, bat activity was monitored over 3 drained and 3 undrained reference bays surrounded by pine/mixed hardwood communities and 3 drained and 3 undrained reference bays surrounded by pine monocultures. Bat activity was monitored using time expansion bat detectors. Calls were recorded to Sony Professional tape recorders (Sony WMD3). Detectors positioned at 10 m heights were linked directly to the tape recorders. Time expansion radiomicrophones were used to monitor activity at 30 m heights. The radiomicrophones were attached to 2-m diameter helium balloons and suspended approximately 30 m above the forest floor. Calls detected by the radiomicrophones were transmitted via a FM narrowband frequency to a scanner on the ground.

  11. Experimental exposure to cadmium affects metallothionein-like protein levels but not survival and growth in wolf spiders from polluted and reference populations.

    PubMed

    Eraly, Debbie; Hendrickx, Frederik; Bervoets, Lieven; Lens, Luc

    2010-06-01

    Both local adaptation and acclimation in tolerance mechanisms may allow populations to persist under metal pollution. However, both mechanisms are presumed to incur (energetic) costs and to trade-off with other life-history traits. To test this hypothesis, we exposed Pardosa saltans (Lycosidae) spiderlings originating from metal-polluted and unpolluted sites to a controlled cadmium (Cd) treatment, and compared contents of metal-binding metallothionein-like proteins (MTLPs), internal metal concentrations, and individual survival and growth rates with a reference treatment. While increased MTLP concentrations in offspring originating from both polluted and unpolluted populations upon exposure indicates a plastic tolerance mechanism, survival and growth rates remain largely unaffected, independent of the population of origin. However, MTLP and Cd concentrations were not significantly correlated. We suggest that MTLP production may be an important mechanism enabling P. saltans populations to persist in ecosystems polluted with heavy metals above a certain level.

  12. A field study on serum vitellogenin levels in male Reeves' pond turtles (Chinemys reevesii) from estrogen-contaminated sites and a reference site.

    PubMed

    Tada, Noriko; Saka, Masahiro; Shiraishi, Fujio; Kamata, Yoichi

    2007-10-01

    To ascertain whether wild male turtles were influenced by environmental estrogens, we examined serum vitellogenin (VTG) levels of male Reeves' pond turtles (Chinemys reevesii) collected from four study sites (A-D) in Kyoto, Japan. Sites A-C, which were impacted by domestic or industrial wastewater and effluents from sewage treatment plants, were chosen as contaminated sites, and site D was intended as a reference site. This contaminated/reference site characterization was confirmed by measuring estrogenic activities of the water samples collected at each site for over a year. Serum VTG levels in the turtles were quantified by an enzyme-linked immunosorbent assay established previously. Estrogenic activities of the water samples were measured using a previously validated yeast two-hybrid assay and expressed as the estradiol-17beta equivalent. Estrogenic activity was observed at high levels at sites A-C, but was almost undetected at site D throughout the sampling period: the mean and range were 0.74 (<0.07-2.1), 0.52 (0.17-1.6), 1.7 (<0.07-7.3), and 0.07 (<0.07-0.62) ng/l at sites A-D, respectively. Significant differences were found only in site D versus sites A, B, and C. Therefore, site D and sites A-C were confirmed to be a reference site and contaminated ones, respectively. Overall, 320 male turtles were captured and examined. The majority of the turtles showed normal VTG values (0.10-0.74 microg/ml). Although only five turtles from sites A-C showed unusually high VTG values (1.1-5.9 microg/ml, nearly one order of magnitude higher than normal values but much lower than values in adult females), there was no significant difference in the incidence of these high values between sites A-C and site D. Moreover, among the five turtles, one turtle was captured again 2 months later, but its VTG value dropped to the normal level. The unusually high VTG values may therefore be transient elevation caused by incidental and/or individually specific agents. Excluding the

  13. THE ESTABLISHMENT OF LOCAL DIAGNOSTIC REFERENCE LEVELS IN ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY: A PRACTICAL TOOL FOR THE OPTIMISATION AND FOR QUALITY ASSURANCE MANAGEMENT.

    PubMed

    Saukko, E; Henner, A; Nieminen, M T; Ahonen, S-M

    2016-02-29

    Fluoroscopic procedures are an area of special concern in relation to radiation protection. The aim of this study was to describe the current level of patient radiation doses in endoscopic retrograde cholangiopancreatography (ERCP) collected from a single centre, as well as to establish and review local diagnostic reference levels (DRLs) in ERCP. A total of 100 patients' radiation doses in ERCP were recorded, and the third-quartile method was adopted to establish local DRLs for ERCP. The mean dose area product (DAP) was 2.05 Gy cm(2), fluoroscopy time (FT) 1.7 min and the number of images was 3. The proposed local DRLs for ERCP were 3.00 Gy cm(2) and 3.0 min. Local DRLs were reviewed in a sample of 25 patients 5 y after they had been established. In reviewing data, the averages of DAP and FT were below the local DRLs. Local DRLs help in the optimisation process of fluoroscopic procedures and guides to a good clinical practice.

  14. Reference Point Heterogeneity

    PubMed Central

    Terzi, Ayse; Koedijk, Kees; Noussair, Charles N.; Pownall, Rachel

    2016-01-01

    It is well-established that, when confronted with a decision to be taken under risk, individuals use reference payoff levels as important inputs. The purpose of this paper is to study which reference points characterize decisions in a setting in which there are several plausible reference levels of payoff. We report an experiment, in which we investigate which of four potential reference points: (1) a population average payoff level, (2) the announced expected payoff of peers in a similar decision situation, (3) a historical average level of earnings that others have received in the same task, and (4) an announced anticipated individual payoff level, best describes decisions in a decontextualized risky decision making task. We find heterogeneity among individuals in the reference points they employ. The population average payoff level is the modal reference point, followed by experimenter's stated expectation of a participant's individual earnings, followed in turn by the average earnings of other participants in previous sessions of the same experiment. A sizeable share of individuals show multiple reference points simultaneously. The reference point that best fits the choices of the individual is not affected by a shock to her income. PMID:27672374

  15. Reference Point Heterogeneity.

    PubMed

    Terzi, Ayse; Koedijk, Kees; Noussair, Charles N; Pownall, Rachel

    2016-01-01

    It is well-established that, when confronted with a decision to be taken under risk, individuals use reference payoff levels as important inputs. The purpose of this paper is to study which reference points characterize decisions in a setting in which there are several plausible reference levels of payoff. We report an experiment, in which we investigate which of four potential reference points: (1) a population average payoff level, (2) the announced expected payoff of peers in a similar decision situation, (3) a historical average level of earnings that others have received in the same task, and (4) an announced anticipated individual payoff level, best describes decisions in a decontextualized risky decision making task. We find heterogeneity among individuals in the reference points they employ. The population average payoff level is the modal reference point, followed by experimenter's stated expectation of a participant's individual earnings, followed in turn by the average earnings of other participants in previous sessions of the same experiment. A sizeable share of individuals show multiple reference points simultaneously. The reference point that best fits the choices of the individual is not affected by a shock to her income.

  16. Patient radiation doses in interventional cardiology in the U.S.: Advisory data sets and possible initial values for U.S. reference levels

    SciTech Connect

    Miller, Donald L.; Hilohi, C. Michael; Spelic, David C.

    2012-10-15

    Purpose: To determine patient radiation doses from interventional cardiology procedures in the U.S and to suggest possible initial values for U.S. benchmarks for patient radiation dose from selected interventional cardiology procedures [fluoroscopically guided diagnostic cardiac catheterization and percutaneous coronary intervention (PCI)]. Methods: Patient radiation dose metrics were derived from analysis of data from the 2008 to 2009 Nationwide Evaluation of X-ray Trends (NEXT) survey of cardiac catheterization. This analysis used deidentified data and did not require review by an IRB. Data from 171 facilities in 30 states were analyzed. The distributions (percentiles) of radiation dose metrics were determined for diagnostic cardiac catheterizations, PCI, and combined diagnostic and PCI procedures. Confidence intervals for these dose distributions were determined using bootstrap resampling. Results: Percentile distributions (advisory data sets) and possible preliminary U.S. reference levels (based on the 75th percentile of the dose distributions) are provided for cumulative air kerma at the reference point (K{sub a,r}), cumulative air kerma-area product (P{sub KA}), fluoroscopy time, and number of cine runs. Dose distributions are sufficiently detailed to permit dose audits as described in National Council on Radiation Protection and Measurements Report No. 168. Fluoroscopy times are consistent with those observed in European studies, but P{sub KA} is higher in the U.S. Conclusions: Sufficient data exist to suggest possible initial benchmarks for patient radiation dose for certain interventional cardiology procedures in the U.S. Our data suggest that patient radiation dose in these procedures is not optimized in U.S. practice.

  17. Fibrosis is worse in HIV-HCV patients with low-level immunodepression referred for HCV treatment than in HCV-matched patients.

    PubMed

    Rullier, Anne; Trimoulet, Pascale; Neau, Didier; Bernard, Pierre-Henri; Foucher, Juliette; Lacoste, Denis; Winnock, Maria; Urbaniak, Rosa; Ballardini, Giorgio; Balabaud, Charles; Bioulac-Sage, Paulette; Le Bail, Brigitte

    2004-09-01

    Hepatitis C virus (HCV) infection is frequent in human immunodeficiency virus (HIV)-infected patients. It is known to have an aggressive course in significantly immunosuppressed patients, and cirrhosis C has become one of the main causes of mortality in HIV-HCV coinfected patients since the improvement of antiretroviral therapy. The reasons for this severe fibrotic evolution are unclear. This prospective study compared chronic HCV lesions, liver immunocompetent cells, fibrosis and liver HCV loads in 2 cohorts of naive patients referred for HCV treatment: 33 HIV-HCV coinfected patients with CD4 >250/microL and 33 HCV-infected patients matched for the main risk factors of fibrosis. Fibrosis, particularly perisinusoidal fibrosis, was more marked in the coinfected patients. This occurred in the absence of a significant difference in disease activity. The number of CD3+ cells in the liver was higher in the HIV-HCV patients than in the HCV patients. Conversely, the number of liver CD4+ cells was lower in HIV-HCV patients than in HCV patients. The numbers of CD8+ and CD68+ cells were similar in the 2 groups. Finally, liver HCV load, assessed by immunostaining and reverse-transcription polymerase chain reaction, was similar in the 2 groups. We conclude that in the population of HIV-HCV coinfected patients with low-level immunosuppression referred for HCV treatment, fibrosis is worse than in HCV patients and the proportion of CD4+ lymphocytes among CD3+ cells is markedly decreased in the liver, whereas intrahepatic viral load is similar. Our data confirm the need to treat such patients against HCV, and suggest that HIV infection could favor fibrosis via the modulation of the intrahepatic immune response.

  18. Pedo-geochemical baseline content levels and soil quality reference values of trace elements in soils from the Mediterranean (Castilla La Mancha, Spain)

    NASA Astrophysics Data System (ADS)

    Ballesta, Raimundo; Bueno, Paz; Rubi, Juan; Giménez, Rosario

    2010-12-01

    To evaluate trace element soil contamination, geochemical baseline contents and reference values need to be established. Pedo-geochemical baseline levels of trace elements in 72 soil samples of 24 soil profiles from the Mediterranean, Castilla La Mancha, are assessed and soil quality reference values are calculated. Reference value contents (in mg kg-1) were: Sc 50.8; V 123.2; Cr 113.4; Co 20.8; Ni 42.6; Cu 27.0; Zn 86.5; Ga 26.7; Ge 1.3; As 16.7; Se 1.4; Br 20.1; Rb 234.7; Sr 1868.4; Y 38.3; Zr 413.1; Nb 18.7; Mo 2.0; Ag 7.8; Cd 4.4; Sn 8.7; Sb 5.7; I 25.4; Cs 14.2; Ba 1049.3; La 348.4; Ce 97.9; Nd 40.1; Sm 10.7; Yb 4.2; Hf 10.0; Ta 4.0; W 5.5; Tl 2.3; Pb 44.2; Bi 2.2; Th 21.6; U 10.3. The contents obtained for some elements are below or close to the detection limit: Co, Ge, Se, Mo, Ag, Cd, Sb, Yb, Hf, Ta, W, Tl and Bi. The element content ranges (the maximum value minus the minimum value) are: Sc 55.0, V 196.0, Cr 346.0, Co 64.4, Ni 188.7, Cu 49.5, Zn 102.3, Ga 28.7, Ge 1.5, As 26.4, Se 0.9, Br 33.0 Rb 432.7, Sr 3372.6, Y 39.8, Zr 523.2, Nb 59.7, Mo 3.9, Ag 10.1, Cd 1.8, Sn 75.2, Sb 9.9, I 68.0, Cs 17.6, Ba 1394.9, La 51.3, Ce 93.5, Nd 52.5, Sm 11.2, Yb 4.2, Hf 11.3, Ta 6.3, W 5.2, Tl 2.1, Pb 96.4, Bi 3.0, Th 24.4, U 16.4 (in mg kg-1). The spatial distribution of the elements was affected mainly by the nature of the bedrock and by pedological processes. The upper limit of expected background variation for each trace element in the soil is documented, as is its range as a criterion for evaluating which sites may require decontamination.

  19. Reference Services.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    1999-01-01

    Discusses library reference services. Topics include the historical development of reference services; instruction in library use, particularly in college and university libraries; guidance; information and referral services and how they differ from traditional question-answering service; and future concerns, including user fees and the planning…

  20. Reference Assessment

    ERIC Educational Resources Information Center

    Bivens-Tatum, Wayne

    2006-01-01

    This article presents interesting articles that explore several different areas of reference assessment, including practical case studies and theoretical articles that address a range of issues such as librarian behavior, patron satisfaction, virtual reference, or evaluation design. They include: (1) "Evaluating the Quality of a Chat Service"…

  1. Reference Revolutions.

    ERIC Educational Resources Information Center

    Mason, Marilyn Gell

    1998-01-01

    Describes developments in Online Computer Library Center (OCLC) electronic reference services. Presents a background on networked cataloging and the initial implementation of reference services by OCLC. Discusses the introduction of OCLC FirstSearch service, which today offers access to over 65 databases, future developments in integrated…

  2. SU-E-P-08: Establishment of Local Diagnostic Reference Levels of Routine Abdomen Exam in Computed Tomography According to Body Weight

    SciTech Connect

    Wang, H; Wang, Y; Weng, H

    2015-06-15

    Purpose: The national diagnostic reference levels (NDRLs) is an efficient, concise and powerful standard for optimizing radiation protection of a patient. However, for each hospital the dose-reducing potential of focusing on establishment of local DRLs (LDRLs). A lot of study reported that Computed tomography exam contributed majority radiation dose in different medical modalities, therefore, routine abdomen CT exam was choose in initial pilot study in our study. Besides the mAs of routine abdomen CT exam was decided automatic exposure control by linear attenuation is relate to body shape of patient. In this study we would like to establish the local diagnostic reference levels of routine abdomen exam in computed tomography according to body weight of patient. Methods and Materials: There are two clinical CT scanners (a Toshiba Aquilion and a Siemens Sensation) were performed in this study. For CT examinations the basic recommended dosimetric quantity is the Computed Tomography Dose Index (CTDI). The patient sample involved 82 adult patients of both sexes and divided into three groups by their body weight (50–60 kg, 60–70 kg, 70–80 kg).Carried out the routine abdomen examinations, and all exposure parameters have been collected and the corresponding CTDIv and DLP values have been determined. The average values were compared with the European DRLs. Results: The majority of patients (75%) were between 50–70 Kg of body weight, the numbers of patient in each group of weight were 40–50:7; 50–60:29; 60–70:33; 70–80:13. The LDRLs in each group were 10.81mGy, 14.46mGy, 20.27mGy and 21.04mGy, respectively. The DLP were 477mGy, 630mGy, 887mGy and 959mGy, respectively. No matter which group the LDRLs were lower than European DRLs. Conclusions: We would like to state that this was a pioneer work in local hospital in Chiayi. We hope that this may lead the way to further developments in Taiwan.

  3. Radiation dose in coronary angiography and intervention: initial results from the establishment of a multi-centre diagnostic reference level in Queensland public hospitals

    SciTech Connect

    Crowhurst, James A; Whitby, Mark; Thiele, David; Halligan, Toni; Westerink, Adam; Crown, Suzanne; Milne, Jillian

    2014-09-15

    Radiation dose to patients undergoing invasive coronary angiography (ICA) is relatively high. Guidelines suggest that a local benchmark or diagnostic reference level (DRL) be established for these procedures. This study sought to create a DRL for ICA procedures in Queensland public hospitals. Data were collected for all Cardiac Catheter Laboratories in Queensland public hospitals. Data were collected for diagnostic coronary angiography (CA) and single-vessel percutaneous intervention (PCI) procedures. Dose area product (P{sub KA}), skin surface entrance dose (K{sub AR}), fluoroscopy time (FT), and patient height and weight were collected for 3 months. The DRL was set from the 75th percentile of the P{sub KA.} 2590 patients were included in the CA group where the median FT was 3.5 min (inter-quartile range = 2.3–6.1). Median K{sub AR} = 581 mGy (374–876). Median P{sub KA} = 3908 uGym{sup 2} (2489–5865) DRL = 5865 uGym{sup 2}. 947 patients were included in the PCI group where median FT was 11.2 min (7.7–17.4). Median K{sub AR} = 1501 mGy (928–2224). Median P{sub KA} = 8736 uGym{sup 2} (5449–12,900) DRL = 12,900 uGym{sup 2}. This study established a benchmark for radiation dose for diagnostic and interventional coronary angiography in Queensland public facilities.

  4. Ready Reference.

    ERIC Educational Resources Information Center

    Koltay, Emery

    1999-01-01

    Includes the following ready reference information: "Publishers' Toll-Free Telephone Numbers"; "How to Obtain an ISBN (International Standard Book Number)"; "How to Obtain an ISSN (International Standard Serial Number)"; and "How to Obtain an SAN (Standard Address Number)". (AEF)

  5. Study of the Vitamin D Levels in Patients Referred to Clinical Laboratories in Mashhad in 2015 and their Relationship with the Patients’ Lipid Profiles

    PubMed Central

    Shamsian, Ali Akbar; Rezaee, Seyyed Abdolrahim; Rajabiian, Majid; Moghaddam, Habibolah Taghizadeh; Saeidi, Masumeh; Bahreini, Abbas

    2016-01-01

    Introduction Vitamin D is a steroid hormone that has a significant role in the metabolism of minerals, especially calcium and phosphorus; it also is a major determinant of the strength of bones. This hormone has a significant effect on three major health issues that people worldwide encounter, i.e., high blood pressure, cancer, and diabetes. Considering the limited and dispersed studies on the prevalence of vitamin D deficiency in Iran and the relationship of vitamin D with lipid profiles in different people, this study was conducted to determine the vitamin D levels in patients and its relationship with their lipid profiles. Methods A retrospective cross-sectional study was conducted in 2015 on 1,110 patients who were referred to the two laboratories at Jihad Daneshgahi and to eight specialist laboratories in Mashhad through random sampling of patients for whom serum vitamin D and serum lipid tests were prescribed. The data that were obtained were entered into SPSS 13 software. Results Sixty-eight percent of the patients in the study were deficient in vitamin D. The vitamin D levels in males were significantly lower than those in females (p < 0.05). The relationship between age and vitamin D deficiency was significant as well (p < 0.05). A positive and significant relationship was observed between age and vitamin D deficiency (p = 0.000, r = 0.187), i.e., vitamin D deficiency was more apparent in patients whose ages were in the range of 40–59. The relationship between the levels of vitamin D and serum lipids was significant and positive (p = 0.05), with the exception of LDL. Conclusion About two-thirds of the population that was studied had a vitamin D deficiency. There was a positive and significant relationship between serum vitamin D and serum lipids and serum calcium. The results of this study showed the necessity for more research and the implementation of preventive measures related to vitamin D deficiency. It is recommended that vitamin D enrichment

  6. EPA QUICK REFERENCE GUIDES

    EPA Science Inventory

    EPA Quick Reference Guides are compilations of information on chemical and biological terrorist agents. The information is presented in consistent format and includes agent characteristics, release scenarios, health and safety data, real-time field detection, effect levels, samp...

  7. Cross-Platform Microarray Meta-Analysis for the Mouse Jejunum Selects Novel Reference Genes with Highly Uniform Levels of Expression

    PubMed Central

    Meyer, Florian R. L.; Grausgruber, Heinrich; Binter, Claudia; Mair, Georg E.; Guelly, Christian; Vogl, Claus; Steinborn, Ralf

    2013-01-01

    Reference genes (RGs) with uniform expression are used for normalization of reverse transcription quantitative PCR (RT-qPCR) data. Their optimization for a specific biological context, e.g. a specific tissue, has been increasingly considered. In this article, we compare RGs identified by expression data meta-analysis restricted to the context tissue, the jejunum of Mus musculus domesticus, i) to traditional RGs, ii) to expressed interspersed repeated DNA elements, and iii) to RGs identified by meta-analysis of expression data from diverse tissues and conditions. To select the set of candidate RGs, we developed a novel protocol for the cross-platform meta-analysis of microarray data. The expression stability of twenty-four putative RGs was analysed by RT-qPCR in at least 14 jejunum samples of the mouse strains C57Bl/6N, CD1, and OF1. Across strains, the levels of expression of the novel RGs Plekha7, Zfx, and Ube2v1 as well as of Oaz1 varied less than two-fold irrespective of genotype, sex or their combination. The gene set consisting of Plekha7 and Oaz1 showed superior expression stability analysed with the tool RefFinder. The novel RGs are functionally diverse. This facilitates expression studies over a wide range of conditions. The highly uniform expression of the optimized RGs in the jejunum points towards their involvement in tightly regulated pathways in this tissue. We also applied our novel protocol of cross-microarray platform meta-analysis to the identification of RGs in the duodenum, the ileum and the entire small intestine. The selection of RGs with improved expression stability in a specific biological context can reduce the number of RGs for the normalization step of RT-qPCR expression analysis, thus reducing the number of samples and experimental costs. PMID:23671661

  8. Radiation dose in coronary angiography and intervention: initial results from the establishment of a multi-centre diagnostic reference level in Queensland public hospitals

    PubMed Central

    Crowhurst, James A; Whitby, Mark; Thiele, David; Halligan, Toni; Westerink, Adam; Crown, Suzanne; Milne, Jillian

    2014-01-01

    Introduction Radiation dose to patients undergoing invasive coronary angiography (ICA) is relatively high. Guidelines suggest that a local benchmark or diagnostic reference level (DRL) be established for these procedures. This study sought to create a DRL for ICA procedures in Queensland public hospitals. Methods Data were collected for all Cardiac Catheter Laboratories in Queensland public hospitals. Data were collected for diagnostic coronary angiography (CA) and single-vessel percutaneous intervention (PCI) procedures. Dose area product (PKA), skin surface entrance dose (KAR), fluoroscopy time (FT), and patient height and weight were collected for 3 months. The DRL was set from the 75th percentile of the PKA. Results 2590 patients were included in the CA group where the median FT was 3.5 min (inter-quartile range = 2.3–6.1). Median KAR = 581 mGy (374–876). Median PKA = 3908 uGym2 (2489–5865) DRL = 5865 uGym2. 947 patients were included in the PCI group where median FT was 11.2 min (7.7–17.4). Median KAR = 1501 mGy (928–2224). Median PKA = 8736 uGym2 (5449–12,900) DRL = 12,900 uGym2. Conclusion This study established a benchmark for radiation dose for diagnostic and interventional coronary angiography in Queensland public facilities. PMID:26229649

  9. Nicotine, acetanilide and urea multi-level 2H-, 13C- and 15N-abundance reference materials for continuous-flow isotope ratio mass spectrometry.

    PubMed

    Schimmelmann, Arndt; Albertino, Andrea; Sauer, Peter E; Qi, Haiping; Molinie, Roland; Mesnard, François

    2009-11-01

    Accurate determinations of stable isotope ratios require a calibration using at least two reference materials with different isotopic compositions to anchor the isotopic scale and compensate for differences in machine slope. Ideally, the delta values of these reference materials should bracket the isotopic range of samples with unknown delta values. While the practice of analyzing two isotopically distinct reference materials is common for water (VSMOW-SLAP) and carbonates (NBS 19 and L-SVEC), the lack of widely available organic reference materials with distinct isotopic composition has hindered the practice when analyzing organic materials by elemental analysis/isotope ratio mass spectrometry (EA-IRMS). At present only L-glutamic acids USGS40 and USGS41 satisfy these requirements for delta13C and delta15N, with the limitation that L-glutamic acid is not suitable for analysis by gas chromatography (GC). We describe the development and quality testing of (i) four nicotine laboratory reference materials for on-line (i.e. continuous flow) hydrogen reductive gas chromatography-isotope ratio mass-spectrometry (GC-IRMS), (ii) five nicotines for oxidative C, N gas chromatography-combustion-isotope ratio mass-spectrometry (GC-C-IRMS, or GC-IRMS), and (iii) also three acetanilide and three urea reference materials for on-line oxidative EA-IRMS for C and N. Isotopic off-line calibration against international stable isotope measurement standards at Indiana University adhered to the 'principle of identical treatment'. The new reference materials cover the following isotopic ranges: delta2H(nicotine) -162 to -45 per thousand, delta13C(nicotine) -30.05 to +7.72 per thousand, delta15N(nicotine) -6.03 to +33.62 per thousand; delta15N(acetanilide) +1.18 to +40.57 per thousand; delta13C(urea) -34.13 to +11.71 per thousand, delta15N(urea) +0.26 to +40.61 per thousand (recommended delta values refer to calibration with NBS 19, L-SVEC, IAEA-N-1, and IAEA-N-2). Nicotines fill a gap as

  10. Nicotine, acetanilide and urea multi-level2H-,13C- and15N-abundance reference materials for continuous-flow isotope ratio mass spectrometry

    USGS Publications Warehouse

    Schimmelmann, A.; Albertino, A.; Sauer, P.E.; Qi, H.; Molinie, R.; Mesnard, F.

    2009-01-01

    Accurate determinations of stable isotope ratios require a calibration using at least two reference materials with different isotopic compositions to anchor the isotopic scale and compensate for differences in machine slope. Ideally, the S values of these reference materials should bracket the isotopic range of samples with unknown S values. While the practice of analyzing two isotopically distinct reference materials is common for water (VSMOW-SLAP) and carbonates (NBS 19 and L-SVEC), the lack of widely available organic reference materials with distinct isotopic composition has hindered the practice when analyzing organic materials by elemental analysis/isotope ratio mass spectrometry (EA-IRMS). At present only L-glutamic acids USGS40 and USGS41 satisfy these requirements for ??13C and ??13N, with the limitation that L-glutamic acid is not suitable for analysis by gas chromatography (GC). We describe the development and quality testing of (i) four nicotine laboratory reference materials for on-line (i.e. continuous flow) hydrogen reductive gas chromatography-isotope ratio mass-spectrometry (GC-IRMS), (ii) five nicotines for oxidative C, N gas chromatography-combustion-isotope ratio mass-spectrometry (GC-C-IRMS, or GC-IRMS), and (iii) also three acetanilide and three urea reference materials for on-line oxidative EA-IRMS for C and N. Isotopic off-line calibration against international stable isotope measurement standards at Indiana University adhered to the 'principle of identical treatment'. The new reference materials cover the following isotopic ranges: ??2Hnicotine -162 to -45%o, ??13Cnicotine -30.05 to +7.72%, ?? 15Nnicotine -6.03 to +33.62%; ??15N acetanilide +1-18 to +40.57%; ??13Curea -34.13 to +11.71%, ??15Nurea +0.26 to +40.61% (recommended ?? values refer to calibration with NBS 19, L-SVEC, IAEA-N-1, and IAEA-N-2). Nicotines fill a gap as the first organic nitrogen stable isotope reference materials for GC-IRMS that are available with different ??13N

  11. Poroelastic references

    SciTech Connect

    Morency, Christina

    2014-12-12

    This file contains a list of relevant references on the Biot theory (forward and inverse approaches), the double-porosity and dual-permeability theory, and seismic wave propagation in fracture porous media, in RIS format, to approach seismic monitoring in a complex fractured porous medium such as Brady?s Geothermal Field.

  12. Ready Reference.

    ERIC Educational Resources Information Center

    Koltay, Emery

    2001-01-01

    Includes four articles that relate to ready reference, including a list of publishers' toll-free telephone numbers and Web sites; how to obtain an ISBN (International Standard Book Number) and an ISSN (International Standard Serial Number); and how to obtain an SAN (Standard Address Number), for organizations that are involved in the book…

  13. Relevance of biotic pathways to the long-term regulation of nuclear-waste disposal. Topical Report on reference western arid low-level sites

    NASA Astrophysics Data System (ADS)

    McKenzie, D. H.; Cadwell, L. L.; Eberhardt, L. E.; Kennedy, W. E., Jr.; Peloquin, R. A.; Simmons, M. A.

    1982-10-01

    An order of magnitude estimate for the potential dose to man resulting from biotic transport mechanisms at a reference western arid lowlevel waste site was developed. A description of the reference site is presented that includes the waste inventories, site characteristics and biological communities. Parameter values for biotic transport processes are based on data reported in current literature. Transport and exposure scenarios are developed for assessing biotic transport during 100 years following site closure. Calculations of radionuclide decay and waste container decomposition are made to estimate the quantities available for biotic transport. Dose to a man occupying the reference site following the 100 years of biotic transport are calculated. Dose to man estimates as a result of biotic transport are estimated to be of the same order of magnitude as the dose resulting from the more commonly evaluated human intrusion scenario.

  14. Assessing the Accuracy of Continuous Glucose Monitoring (CGM) Calibrated With Capillary Values Using Capillary or Venous Glucose Levels as a Reference

    PubMed Central

    Andelin, Mervi; Kropff, Jort; Matuleviciene, Viktorija; Joseph, Jeffrey I.; Attvall, Stig; Theodorsson, Elvar; Hirsch, Irl B.; Imberg, Henrik; Dahlqvist, Sofia; Klonoff, David; Haraldsson, Börje; DeVries, J. Hans; Lind, Marcus

    2016-01-01

    Background: Using the standard venous reference for the evaluation of continuous glucose monitoring (CGM) systems could possibly negatively affect measured CGM accuracy since CGM are generally calibrated with capillary glucose and venous and capillary glucose concentrations differ. We therefore aimed to quantify the effect of using capillary versus venous glucose reference samples on estimated accuracy in capillary calibrated CGM. Methods: We evaluated 41 individuals with type 1 diabetes mellitus (T1DM) using the Dexcom G4 CGM system over 6 days. Patients calibrated their CGM devices with capillary glucose by means of the HemoCue system. During 2 visits, capillary and venous samples were simultaneously measured by HemoCue and compared to concomitantly obtained CGM readings. The mean absolute relative difference (MARD) was calculated using capillary and venous reference samples. Results: Venous glucose values were 0.83 mmol/L (15.0 mg/dl) lower than capillary values over all glycemic ranges, P < .0001. Below 4 mmol/l (72 mg/dl), the difference was 1.25 mmol/l (22.5 mg/dl), P = .0001, at 4-10 mmol/l (72-180 mg/dl), 0.67 mmol/l (12.0 mg/dl), P < .0001 and above 10 mmol/l (180 mg/dl), 0.95 mmol/l (17.1 mg/dl), P < .0001. MARD was 11.7% using capillary values as reference compared to 13.7% using venous samples, P = .037. Below 4 mmol/l (72 mg/dl) MARD was 16.6% and 31.8%, P = .048, at 4-10 mmol/l (72-180 mg/dl) 12.1% and 12.6%, P = .32, above 10 mmol/l (180 mg/dl) 8.7% and 9.2%, P = .82. Conclusion: Using capillary glucose concentrations as reference to evaluate the accuracy of CGM calibrated with capillary samples is associated with a lower MARD than using venous glucose as the reference. Capillary glucose concentrations were significantly higher than venous in all glycemic ranges. PMID:26810924

  15. In-vivo assessment of tissue metabolite levels using 1H MRS and the Electric REference To access In vivo Concentrations (ERETIC) method.

    PubMed

    Heinzer-Schweizer, S; De Zanche, N; Pavan, M; Mens, G; Sturzenegger, U; Henning, A; Boesiger, P

    2010-05-01

    Quantitative values of metabolite concentrations in (1)H magnetic resonance spectroscopy have been obtained using the Electric REference To access In vivo Concentrations (ERETIC) method, whereby a synthetic reference signal is injected during the acquisition of spectra. The method has been improved to enable quantification of metabolite concentrations in vivo. Optical signal transmission was used to eliminate random fluctuations in ERETIC signal coupling to the receiver coil due to changes in position of cables and highly dielectric human tissue. Stability and reliability of the signal were tested in vitro, achieving stability with a mean error of 2.83%. Scaling of the signal in variable loading conditions was demonstrated and in-vivo measurements of brain were acquired on a 3T Philips system using a transmit/receive coil. The quantitative brain water and metabolite concentration values are in good agreement with those in the literature.

  16. On Development and Characterisation of a Mobile and Metrologically Traceable Reference Gas Generator for Ammonia and Other Reactive Species in Ambient Air Levels

    NASA Astrophysics Data System (ADS)

    Leuenberger, Daiana; Pascale, Céline; Guillevic, Myriam; Ackermann, Andreas; Niederhauser, Bernhard

    2016-04-01

    Ammonia NH3 in the atmosphere is the major precursor for neutralising atmospheric acids and is thus affecting not only the long-range transport of sulphur dioxide and nitrogen oxides but also stabilies secondary particulate matter. These aerosols have negative impacts on air quality and human health. Moreover, they negatively affect terrestrial ecosystems after deposition. NH3 has been included in the air quality monitoring networks and emission reduction directives of European nations. Atmospheric concentrations are in the order of 0.5-500 nmol/mol. However, the lowest substance amount fraction of available certified reference material (CRM) is 30 μmol/mol. The EMRP JRP ENV55 MetNH3 aims at overcoming this discrepancy by assessing and developing novel approaches for the production of CRM and measurement methods. The Federal Institute of Metrology METAS has developed a mobile and metrologically traceable reference gas generator for reactive gases (ReGaS1). This device is based on the specific temperature dependent permeation of the reference substance through a membrane into a flow of carrier gas and subsequent dynamic dilution to desired amount fractions. The characteristics of individual components lead to the uncertainty estimation for the generated NH3 gas mixture according to GUM, which is aimed to be <3 %. Here we present insights into the development of said instrument and results of the first performance tests. Moreover, we include results of the study on adsorption/desorption effects in dry as well as humidified matrix gas into the discussion on the generation of reference gas mixtures.

  17. Cited references and Medical Subject Headings (MeSH) as two different knowledge representations: clustering and mappings at the paper level.

    PubMed

    Leydesdorff, Loet; Comins, Jordan A; Sorensen, Aaron A; Bornmann, Lutz; Hellsten, Iina

    2016-01-01

    For the biomedical sciences, the Medical Subject Headings (MeSH) make available a rich feature which cannot currently be merged properly with widely used citing/cited data. Here, we provide methods and routines that make MeSH terms amenable to broader usage in the study of science indicators: using Web-of-Science (WoS) data, one can generate the matrix of citing versus cited documents; using PubMed/MEDLINE data, a matrix of the citing documents versus MeSH terms can be generated analogously. The two matrices can also be reorganized into a 2-mode matrix of MeSH terms versus cited references. Using the abbreviated journal names in the references, one can, for example, address the question whether MeSH terms can be used as an alternative to WoS Subject Categories for the purpose of normalizing citation data. We explore the applicability of the routines in the case of a research program about the amyloid cascade hypothesis in Alzheimer's disease. One conclusion is that referenced journals provide archival structures, whereas MeSH terms indicate mainly variation (including novelty) at the research front. Furthermore, we explore the option of using the citing/cited matrix for main-path analysis as a by-product of the software.

  18. Feasibility study for producing a carrot/potato matrix reference material for 11 selected pesticides at EU MRL level: material processing, homogeneity and stability assessment.

    PubMed

    Saldanha, Helena; Sejerøe-Olsen, Berit; Ulberth, Franz; Emons, Hendrik; Zeleny, Reinhard

    2012-05-01

    The feasibility for producing a matrix reference material for selected pesticides in a carrot/potato matrix was investigated. A commercially available baby food (carrot/potato-based mash) was spiked with 11 pesticides at the respective EU maximum residue limits (MRLs), and further processed by either freezing or freeze-drying. Batches of some 150 units were produced per material type. First, the materials were assessed for the relative amount of pesticide recovered after processing (ratio of pesticide concentration in the processed material to the initially spiked pesticide concentration). In addition, the materials' homogeneity (bottle-to-bottle variation), and the short-term (1 month) and mid-term (5 months) stability at different temperatures were assessed. For this, an in-house validated GC-EI-MS method operated in the SIM mode with a sample preparation procedure based on the QuEChERS ("quick, easy, cheap, effective, rugged, and safe") principle was applied. Measurements on the frozen material provided the most promising results (smallest analyte losses during production), and also freeze-drying proved to be a suitable alternative processing technique for most of the investigated pesticides. Both the frozen and the freeze-dried material showed to be sufficiently homogeneous for the intended use, and storage at -20°C for 5 months did not reveal any detectable material degradation. The results constitute an important step towards the development of a pesticide matrix reference material.

  19. Humboldt Bay Vertical Reference System Working Group: unraveling tectonic and eustatic factors of sea level rise in northern California, Humboldt Bay

    NASA Astrophysics Data System (ADS)

    Williams, T. B.; Anderson, J. K.; Burgette, R. J.; Gilkerson, W.; Hemphill-Haley, M.; Leroy, T. H.; Patton, J. R.; Southwick, E.; Stallman, J.; Weldon, R. J.

    2012-12-01

    Sea-level rise is a critical factor in managing estuarine ecosystems, maintaining public infrastructure, and mitigating geologic hazards along north coastal California. The coastal region between Fort Bragg, California and Vancouver Island experiences ongoing land-level changes due to Cascadia subduction zone tectonics. These tectonic land-level changes sufficiently modify relative sea level such that sea-level rise cannot be accurately estimated without determining the tectonic contribution. We use tide gages and precise level-loop surveys to observe modern land and water surface elevations around Humboldt Bay. These modern data, combined with historic survey data, will be used to deconfound the various factors contributing to relative sea level change. Independent analysis of existing NOAA tide gages and EarthScope CGPS stations indicate 2.5 mm/yr of land subsidence near Humboldt Bay and 2 mm/yr of land uplift in Crescent City. Presuming the bulk of the strain accumulation is due to the southern portion of the Cascadia subduction zone, these data suggest Humboldt Bay is west of the locked zone, not to the east as previously reported by several researchers.

  20. Implementation of the multireference Brillouin-Wigner and Mukherjee’s coupled cluster methods with non-iterative triple excitations utilizing reference-level parallelism

    SciTech Connect

    Bhaskaran-Nair, Kiran; Brabec, Jiri; Apra, Edoardo; van Dam, Hubertus JJ; Pittner, Jiri; Kowalski, Karol

    2012-09-07

    In this paper we discuss the performance of the non-iterative State-Specific Mul- tireference Coupled Cluster (SS-MRCC) methods accounting for the effect of triply excited cluster amplitudes. The corrections to the Brillouin-Wigner and Mukherjee MRCC models based on the manifold of singly and doubly excited cluster amplitudes (BW-MRCCSD and Mk-MRCCSD, respectively) are tested and compared with the exact full configuration interaction results (FCI) for small systems (H2O, N2, and Be3). For larger systems (naphthyne isomers and -carotene), the non-iterative BW-MRCCSD(T) and Mk-MRCCSD(T) methods are compared against the results obtained with the single reference coupled cluster methods. We also report on the parallel performance of the non-iterative implementations based on the use of pro- cessor groups.

  1. Climate Change, Sea-Level Rise and Implications for Coastal and Estuarine Shoreline Management with Particular Reference to the Ecology of Intertidal Benthic Macrofauna in NW Europe.

    PubMed

    Fujii, Toyonobu

    2012-11-05

    In many European estuaries, extensive areas of intertidal habitats consist of bare mudflats and sandflats that harbour a very high abundance and biomass of macrobenthic invertebrates. The high stocks of macrobenthos in turn provide important food sources for the higher trophic levels such as fish and shorebirds. Climate change and associated sea-level rise will have potential to cause changes in coastal and estuarine physical properties in a number of ways and thereby influence the ecology of estuarine dependent organisms. Although the mechanisms involved in biological responses resulting from such environmental changes are complex, the ecological effects are likely to be significant for the estuarine benthic macrofauna and hence the consumers they support. This paper reviews the utilisation patterns of estuarine intertidal habitats by shorebirds, fish and crustaceans, as well as factors affecting the distribution, abundance and biomass of estuarine macrobenthos that is known to be important food source for these estuarine predators. This study also provides simple conceptual models of the likely impacts of sea-level rise on the physical and biological elements of estuarine intertidal habitats, and implications of these results are discussed in the context of sustainable long term flood and coastal management in estuarine environments.

  2. Climate Change, Sea-Level Rise and Implications for Coastal and Estuarine Shoreline Management with Particular Reference to the Ecology of Intertidal Benthic Macrofauna in NW Europe

    PubMed Central

    Fujii, Toyonobu

    2012-01-01

    In many European estuaries, extensive areas of intertidal habitats consist of bare mudflats and sandflats that harbour a very high abundance and biomass of macrobenthic invertebrates. The high stocks of macrobenthos in turn provide important food sources for the higher trophic levels such as fish and shorebirds. Climate change and associated sea-level rise will have potential to cause changes in coastal and estuarine physical properties in a number of ways and thereby influence the ecology of estuarine dependent organisms. Although the mechanisms involved in biological responses resulting from such environmental changes are complex, the ecological effects are likely to be significant for the estuarine benthic macrofauna and hence the consumers they support. This paper reviews the utilisation patterns of estuarine intertidal habitats by shorebirds, fish and crustaceans, as well as factors affecting the distribution, abundance and biomass of estuarine macrobenthos that is known to be important food source for these estuarine predators. This study also provides simple conceptual models of the likely impacts of sea-level rise on the physical and biological elements of estuarine intertidal habitats, and implications of these results are discussed in the context of sustainable long term flood and coastal management in estuarine environments. PMID:24832510

  3. Validation of reference genes for normalization of qPCR mRNA expression levels in Staphylococcus aureus exposed to osmotic and lactic acid stress conditions encountered during food production and preservation.

    PubMed

    Sihto, Henna-Maria; Tasara, Taurai; Stephan, Roger; Johler, Sophia

    2014-07-01

    Staphylococcus aureus represents the most prevalent cause of food-borne intoxications worldwide. While being repressed by competing bacteria in most matrices, this pathogen exhibits crucial competitive advantages during growth at high salt concentrations or low pH, conditions frequently encountered in food production and preservation. We aimed to identify reference genes that could be used to normalize qPCR mRNA expression levels during growth of S. aureus in food-related osmotic (NaCl) and acidic (lactic acid) stress adaptation models. Expression stability of nine housekeeping genes was evaluated in full (LB) and nutrient-deficient (CYGP w/o glucose) medium under conditions of osmotic (4.5% NaCl) and acidic stress (lactic acid, pH 6.0) after 2-h exposure. Among the set of candidate reference genes investigated, rplD, rpoB,gyrB, and rho were most stably expressed in LB and thus represent the most suitable reference genes for normalization of qPCR data in osmotic or lactic acid stress models in a rich medium. Under nutrient-deficient conditions, expression of rho and rpoB was highly stable across all tested conditions. The presented comprehensive data on changes in expression of various S. aureus housekeeping genes under conditions of osmotic and lactic acid stress facilitate selection of reference genes for qPCR-based stress response models.

  4. Levels of toxic elements and functional structure in populations of small mammals under conditions of technogenic pollution (with reference to the bank vole)

    SciTech Connect

    Mukhacheva, S.V.; Bezel, V.S.

    1995-05-01

    The levels and the character of accumulation of heavy metals (Pb, Cd, Cu, Zn) in organs and tissues of bank voles, living under conditions of technogenic pollution (near a copper-smelting plant) and on the control territory, were studied. The fundamental distinctions in the character of accumulation of physiologically extraneous elements (lead and cadmium) and elements required for normal functioning (copper and zinc) were found. It was shown that the bank vole population responds to technogenic pollution of the environment depending on the ecological-functional features of the subpopulational groups that form this population. 4 refs., 3 figs., 2 tabs.

  5. Lactogenic activity of Teramnus labialis (Linn.) fruit with special reference to the estimation of serum prolactin and cortisol level in nursing rats

    PubMed Central

    Sahoo, Himanshu Bhusan; Bhaiji, Amrita; Santani, Dev Das

    2016-01-01

    Aim: The objective of the study was to investigate the lactogenic activity of methanolic extract of Teramnus labialis (L.) fruit (MTLF) on rats. Subjects and Methods: Nursing rats (200–250 g) with their suckling pups were selected and were divided into five groups (n = 6). Group I treated as control (distil water); Group II treated as standard (domperidone), and Group III, IV, and V were orally administered with MTLF at 200, 400, and 600 mg/kg body weight, respectively and continued for l4th day of parturition. Milk yield, the pups as well as mother's weight were measured daily. On 15th day, the total protein/carbohydrate contents from mammary tissue and serum prolactin/cortisol level from blood sample were measured and compared with control. Results: Oral administration of MTLF increases the milk yield, body weight of pups as well as mother rat, glycogen, and protein content as well as serum prolactin and cortisol level as compared to the control animals. In addition, the lactogenic effect of MTLF was followed dose-dependent manner as compared to control. Conclusions: The present study was revealed that the MTLF possesses significant lactogenic activity by enhancing milk production and prolactin concentration in nursing rats. PMID:28066113

  6. Development of national reference energy mean emission levels for the FHWA traffic noise model (FHWA TNM (trade name)), version 1.0. Final report, July 1993-November 1995

    SciTech Connect

    Fleming, G.G.; Rapoza, A.S.; Lee, C.S.Y.

    1995-11-01

    During the period, July 1993 through November 1995, the U.S. Department of Transportation , Research and Special Programs Administration, John A. Volpe National Transportation Systems Center (Volpe Center), Acoustics Facility. This report also presents the results of the study, including the measurement, data reduction and analysis procedures used to develop the Data Base. It discusses data for constant-flow and interrupted-flow roadway traffic, and data related to vehicle subsource heights. This report also presents the statistical methodology used to establish the Data Base for the FHWA TNM. Sound level regressions are presented as a function of several parameters, including vehicle speed, vehicle type, one-third octave-band frequency, roadway pavement type, roadway grade, traffic-flow condition and vehicle subsource height.

  7. Benchmarking curriculum content in entry-level health professional education with special reference to health promotion practice in physical therapy: a multi-institutional international study.

    PubMed

    Bodner, Michael E; Rhodes, Ryan E; Miller, William C; Dean, Elizabeth

    2013-10-01

    Health promotion (HP) warrants being a clinical competency for health professionals given the global burden of lifestyle-related conditions; these are largely preventable with lifestyle behavior change. Physical therapists have a practice pattern conducive to HP, including lifestyle behavior change. The extent to which HP content is included in entry-level physical therapy (PT) curricula, and how it is taught however, is unknown. The aim of this study was to benchmark lifestyle behavior HP content within entry-level curricula of international PT programs. The sampling frame included 258 accredited PT academic programs spanning six countries. An internet-based survey was used to assess HP curricular content. Descriptive questions for HP topics (smoking cessation, nutrition, weight control, alcohol consumption, exercise, and stress management) included hours allotted and instructional methods used. Chi square tests examined differences between the proportion of programs in the United States (US) and other countries (combined) for HP topics, and among HP topics regarding instructional methods. The response rate was 48 %. Most programs (>80 %) included all HP topics except alcohol consumption (65.5 % of programs). Instructional methods used were primarily theory-based; few programs (range 2.6-24.1 %) combined theory, practical and attainment of clinical competency for all HP topics (exercise prescription notwithstanding). Proportionally, more US programs included alcohol and nutrition than other countries combined. Overall, HP lifestyle behavior topics were included to varying extent; however, instructional methods used and hours allotted per topic varied across PT curricula. Universal standards of HP practice as a clinical competency are warranted within the profession.

  8. Survey of RF exposure levels from mobile telephone base stations in Australia.

    PubMed

    Henderson, S I; Bangay, M J

    2006-01-01

    This paper reports the results of an exposure level survey of radiofrequency electromagnetic energy originating from mobile telephone base station antennas. Measurements of CDMA800, GSM900, GSM1800, and 3G(UMTS) signals were performed at distances ranging over 50 to 500 m from 60 base stations in five Australian cities. The exposure levels from these mobile telecommunications base stations were found to be well below the general public exposure limits of the ICNIRP guidelines and the Australian radiofrequency standard (ARPANSA RPS3). The highest recorded level from a single base station was 7.8 x 10(-3) W/m(2), which translates to 0.2% of the general public exposure limit.

  9. Preliminary report on the geology and hydrology of Mortandad Canyon near Los Alamos, New Mexico, with reference to disposal of liquid low-level radioactive waste

    USGS Publications Warehouse

    Baltz, E.H.; Abrahams, J.H.; Purtyman, W.D.

    1963-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Atomic Energy Commission and the Los Alamos Scientific Laboratory, selected the upper part of Mortandad Canyon near Los Alamos, New Mexico for a site for disposal of treated liquid low-level radioactive waste. This report summarizes the part of a study of the geology and hydrology that was done from October 1960 through June 1961. Additional work is being continued. Mortandad Canyon is a narrow east-southeast-trending canyon about 9? miles long that heads on the central part of the Pajarito Plateau at an altitude of about 7,340 feet. The canyon is tributary to the Rio Grande. The drainage area of the part of Mortandad Canyon that was investigated is about 2 square miles, and the total drainage area is about 4.9 square miles. The Pajarito Plateau is capped by the Bandelier Tuff of Pleistocene age. Mortandad Canyon is cut in the Bandelier, and alluvium covers the floor of the canyon to depths ranging from less than 1 foot to as much as 100 feet. The Bandelier is underlain by silt, sand, conglomerate, and interbedded basalt of the Santa Fe Group of Miocene, Pliocene, and Pleistocene(?) age. Some ground water is perched in the alluvium in the canyon; however, the top of the main aquifer is in the Santa Fe Group at a depth of about 990 feet below the canyon floor. Joints in the Bandelier Tuff probably were caused by shrinkage of the tuff during cooling. The joints range in width from hairline cracks to fissures several inches wide. Water can infiltrate along the open joints where the Bandelier is at the surface; however, soil, alluvial fill, and autochthonous clay inhibit infiltration on the tops of mesas and probably in the alluvium-floored canyons also. Thirty-three test holes, each less than 100 feet deep, were drilled in 10 lies across Mortandad Canyon from the western margin of the study area to just west of the Los Alamos-Santa Fe County line. Ten of the holes were cased for observation wells to measure

  10. Study on Trap Levels in SrSi2AlO2N3:Eu(2+),Ln(3+) Persistent Phosphors Based on Host-Referred Binding Energy Scheme and Thermoluminescence Analysis.

    PubMed

    Zhuang, Yixi; Lv, Ying; Li, Ye; Zhou, Tianliang; Xu, Jian; Ueda, Jumpei; Tanabe, Setsuhisa; Xie, Rong-Jun

    2016-11-21

    We investigated the effect of trivalent lanthanide substitution on a novel oxynitride persistent phosphor SrSi2AlO2N3:Eu(2+),Ln(3+), which shows green persistent luminescence for more than 2 h. First, an energy level diagram by using the host-referred binding energy (HRBE) scheme was constructed. The location of the energy levels of all divalent and trivalent lanthanides referred to the energy band of the host SrSi2AlO2N3 was estimated. Then, thermoluminescence (TL) measurements in the target persistent phosphors were performed to obtain direct experimental results on the trap depth. We found that the trap levels based on the TL measurements coincided well with the 4f ground states of divalent lanthanide codopants in SrSi2AlO2N3:Eu(2+),Ln(3+). The result strongly suggests the effective traps for persistent luminescence in SrSi2AlO2N3:Eu(2+),Ln(3+) could be due to the aliovalent substitution of Ln(3+) for Sr(2+), which can be controlled by selecting suitable codopant Ln(3+). The work shows the HRBE scheme may offer a way to understand the nature of defects in the persistent phosphor as well as a possible guideline to design new persistent phosphors with required trap depths.

  11. SAR changes in a human head model for plane wave exposure (500 - 2500 MHz) and a comparison with IEEE 2005 safety limits.

    PubMed

    Yelkenci, Tanju; Paker, Selcuk

    2008-01-01

    In this paper, external electric field values that are derived from the largest peak average 10 g SAR (Specific Absorption Rate) results in a realistic human head model are compared with current IEEE and ICNIRP reference levels. The head is illuminated by a plane wave source at seven different frequencies ranging from 500 MHz to 2500 MHz, with five different incident directions and three polarizations. Results reveal that the presence of metallic wire spectacles reduces the external electric field levels in the region above 900 MHz. Comparison of derived electric field values shows that the current IEEE and ICNIRP safety limits provide a conservative estimate.

  12. Reference Frames and Relativity.

    ERIC Educational Resources Information Center

    Swartz, Clifford

    1989-01-01

    Stresses the importance of a reference frame in mechanics. Shows the Galilean transformation in terms of relativity theory. Discusses accelerated reference frames and noninertial reference frames. Provides examples of reference frames with diagrams. (YP)

  13. Genetics Home Reference: isolated hyperchlorhidrosis

    MedlinePlus

    ... loss of salt (sodium chloride or NaCl) in sweat. In particular, "hyperchlorhidrosis" refers to the high levels of chloride found in sweat, although both sodium and chloride are released. Because ...

  14. THLL (TRIDENT Higher Level Language) Reference Manual.

    DTIC Science & Technology

    1984-07-01

    COMPONENT id ( sext FIELD (sb, nb), OFFSET n) where type is one of the keywords INTEGER, POINTER; id is the component identifier; sext is one of the...id-list sext FIELD (sb, nb) FOR id-list ; F OFFSET n FOR id-list where type is one of the keywords INTEGER, DOUBLE, REAL, POINTER; id-list is a list of...identifiers separated by commas; sext is one of the keywords ARITHMETIC, LOGICAL. It can be omitted, in which case the default LOGICAL is assumed; sb

  15. SPAR reference manual update SPAR level 15

    NASA Technical Reports Server (NTRS)

    Whetstone, W. D.

    1980-01-01

    Command runstream elements are presented for analyzing structural systems that are composed of a number of cyclically symmetrical sectors. Provisions are included for systems in which each cyclically symmetrical sector also possesses a plane of reflective symmetry. The following types of analysis may be performed: static analysis with and without preload, vibrational analysis with and without preload, and buckling analysis with and without preload.

  16. Comparisons of CVID and IgGSD: referring physicians, autoimmune conditions, pneumovax reactivity, immunoglobulin levels, blood lymphocyte subsets, and HLA-A and -B typing in 432 adult index patients.

    PubMed

    Barton, James C; Bertoli, Luigi F; Barton, J Clayborn

    2014-01-01

    Common variable immunodeficiency (CVID) and immunoglobulin (Ig) G subclass deficiency (IgGSD) are heterogeneous disorders characterized by respiratory tract infections, selective Ig isotype deficiencies, and impaired antibody responses to polysaccharide antigens. Using univariable analyses, we compared observations in 34 CVID and 398 IgGSD adult index patients (81.9% women) referred to a hematology/oncology practice. Similarities included specialties of referring physicians, mean ages, proportions of women, reactivity to Pneumovax, median serum IgG3 and IgG4 levels, median blood CD56+/CD16+ lymphocyte levels, positivity for HLA-A and -B types, and frequencies of selected HLA-A, -B haplotypes. Dissimilarities included greater prevalence of autoimmune conditions, lower median IgG, IgA, and IgM, and lower median CD19+, CD3+/CD4+, and CD3+/CD8+ blood lymphocytes in CVID patients. Prevalence of Sjögren's syndrome and hypothyroidism was significantly greater in CVID patients. Combined subnormal IgG1/IgG3 occurred in 59% and 29% of CVID and IgGSD patients, respectively. Isolated subnormal IgG3 occurred in 121 IgGSD patients (88% women). Logistic regression on CVID (versus IgGSD) revealed a significant positive association with autoimmune conditions and significant negative associations with IgG1, IgG3, and IgA and CD56+/CD16+ lymphocyte levels, but the odds ratio was increased for autoimmune conditions alone (6.9 (95% CI 1.3, 35.5)).

  17. Reference Service Policy Statement.

    ERIC Educational Resources Information Center

    Young, William F.

    This reference service policy manual provides general guidelines to encourage reference service of the highest possible quality and to insure uniform practice. The policy refers only to reference service in the University Libraries and is intended for use in conjunction with other policies and procedures issued by the Reference Services Division.…

  18. Effect of predictive value of progesterone level on the day of HCG injection for IVF success in women with infertility due to tubal factor or polycystic ovarian syndrome referred to the women hospital, Tehran, 2009

    PubMed Central

    Ghaseminejad, Azizeh; Rezaee, Zahra; Forootan, Mitra; Hosseinipoor, Taraneh; Forghani, Forough; Nikuei, Pooneh

    2012-01-01

    Background: Polycystic ovarian syndrome is one of the most common causes of endocrine disorders and main reason of infertility due to anovulation and recurrent abortions. Progesterone has been shown to have an important role in fertilization of oocyte and fetal implantation. Objective: The purpose of this study was to compare the predictive value of progesterone level on IVF success in women with infertility due to tubal factor or PCOS. Materials and Methods: In a stratified cohort study, we assigned 76 infertile women of 20-38 years old who referred to women hospital into two equal groups with fallopian tube factor infertility and PCOS. We measured the plasma levels of progesterone and estradiol on the day of HCG administration. The patients were divided into two groups based on progesterone level cut off point of 1.2ng/ml. Thereafter the incidence of pregnancy (chemical by β-HCG measurement and clinical by ultrasonography up to the 6 weeks after fetal transfer) was compared in these groups. Results: Total pregnancy rates were 15.8% in patients with tubal factor infertility and 26.3% in women with PCOS. In women with PCOS, the pregnancy rate was less in patients with progesterone level <1.2 ng/ml. However this difference was not statistically significant. Likewise, we did not observe any significant differences in pregnancy rate in patients with fallopian tube factor infertility. Conclusion: Serum progesterone level on the day of HCG administration is not well predictive of the IVF success in infertile women due to fallopian tube factor or PCOS. To obtain more uniform results, we recommend use of larger samples while the bias variable is taken into account and the ROC curve is used for determination of the unique serum progesterone level. PMID:25246897

  19. Generalizing indexical-functional reference

    SciTech Connect

    Schoppers, M.; Shu, R.

    1996-12-31

    The goals of situated agents generally do not specify particular objects: they require only that some suitable object should be chosen and manipulated (e.g. any red block). Situated agents engaged in deictic reference grounding, however, may well track a chosen referent object with such fixity of purpose that an unchosen object may be regarded as an obstacle even though it satisfies the agent`s goals. In earlier work this problem was bridged by hand-coding. This paper lifts the problem to the symbol level, endowing agents with perceptual referent selection actions and performing those actions as required to allow or disallow opportunistic re-selection of referents. Our work preserves the ability of situated agents to find and track specific objects, adds an ability to automatically exploit the opportunities allowed by nonspecific references, and provides a starting point for studying how much opportunistic perception is appropriate.

  20. Prescription n-3 fatty acids, but not eicosapentaenoic acid alone, improve reference memory-related learning ability by increasing brain-derived neurotrophic factor levels in SHR.Cg-Lepr(cp)/NDmcr rats, a metabolic syndrome model.

    PubMed

    Hashimoto, Michio; Inoue, Takayuki; Katakura, Masanori; Tanabe, Yoko; Hossain, Shahdat; Tsuchikura, Satoru; Shido, Osamu

    2013-10-01

    Metabolic syndrome is implicated in the decline of cognitive ability. We investigated whether the prescription n-3 fatty acid administration improves cognitive learning ability in SHR.Cg-Lepr(cp)/NDmcr (SHR-cp) rats, a metabolic syndrome model, in comparison with administration of eicosapentaenoic acid (EPA, C20:5, n-3) alone. Administration of TAK-085 [highly purified and concentrated n-3 fatty acid formulation containing EPA ethyl ester and docosahexaenoic acid (DHA, C22:6, n-3) ethyl ester] at 300 mg/kg body weight per day for 13 weeks reduced the number of reference memory-related errors in SHR-cp rats, but EPA alone had no effect, suggesting that long-term TAK-085 administration improves cognitive learning ability in a rat model of metabolic syndrome. However, the working memory-related errors were not affected in either of the rat groups. TAK-085 and EPA administration increased plasma EPA and DHA levels of SHR-cp rats, associating with an increase in EPA and DHA in the cerebral cortex. The TAK-085 administration decreased the lipid peroxide levels and reactive oxygen species in the cerebral cortex and hippocampus of SHR-cp rats, suggesting that TAK-085 increases antioxidative defenses. Its administration also increased the brain-derived neurotrophic factor levels in the cortical and hippocampal tissues of TAK-085-administered rats. The present study suggests that long-term TAK-085 administration is a possible therapeutic strategy for protecting against metabolic syndrome-induced learning decline.

  1. Higher levels of phosphorylated Y1472 on GluN2B subunits in the frontal cortex of aged mice are associated with good spatial reference memory, but not cognitive flexibility.

    PubMed

    Zamzow, Daniel R; Elias, Val; Acosta, Varinia A; Escobedo, Emily; Magnusson, Kathy R

    2016-06-01

    The N-methyl-D-aspartate receptor (NMDAr) is particularly vulnerable to aging. The GluN2B subunit of the NMDAr, compared to other NMDAr subunits, suffers the greatest losses of expression in the aging brain, especially in the frontal cortex. While expression levels of GluN2B mRNA and protein in the aged brain are well documented, there has been little investigation into age-related posttranslational modifications of the subunit. In this study, we explored some of the mechanisms that may promote differences in the NMDAr complex in the frontal cortex of aged animals. Two ages of mice, 3 and 24 months, were behaviorally tested in the Morris water maze. The frontal cortex and hippocampus from each mouse were subjected to differential centrifugation followed by solubilization in Triton X-100. Proteins from Triton-insoluble membranes, Triton-soluble membranes, and intracellular membranes/cytosol were examined by Western blot. Higher levels of GluN2B tyrosine 1472 phosphorylation in frontal cortex synaptic fractions of old mice were associated with better reference learning but poorer cognitive flexibility. Levels of GluN2B phosphotyrosine 1336 remained steady, but there were greater levels of the calpain-induced 115 kDa GluN2B cleavage product on extrasynaptic membranes in these old good learners. There was an age-related increase in calpain activity, but it was not associated with better learning. These data highlight a unique aging change for aged mice with good spatial learning that might be detrimental to cognitive flexibility. This study also suggests that higher levels of truncated GluN2B on extrasynaptic membranes are not deleterious to spatial memory in aged mice.

  2. Fundamentals of Reference

    ERIC Educational Resources Information Center

    Mulac, Carolyn M.

    2012-01-01

    The all-in-one "Reference reference" you've been waiting for, this invaluable book offers a concise introduction to reference sources and services for a variety of readers, from library staff members who are asked to work in the reference department to managers and others who wish to familiarize themselves with this important area of…

  3. Live, Digital Reference.

    ERIC Educational Resources Information Center

    Kenney, Brian

    2002-01-01

    Discusses digital reference services, also known as virtual reference, chat reference, or online reference, based on a round table discussion at the 2002 American Library Association annual conference in Atlanta. Topics include numbers and marketing; sustainability; competition and models; evaluation methods; outsourcing; staffing and training;…

  4. Statistical Reference Datasets

    National Institute of Standards and Technology Data Gateway

    Statistical Reference Datasets (Web, free access)   The Statistical Reference Datasets is also supported by the Standard Reference Data Program. The purpose of this project is to improve the accuracy of statistical software by providing reference datasets with certified computational results that enable the objective evaluation of statistical software.

  5. Human health screening level risk assessments of tertiary-butyl acetate (TBAC): calculated acute and chronic reference concentration (RfC) and Hazard Quotient (HQ) values based on toxicity and exposure scenario evaluations.

    PubMed

    Bus, James S; Banton, Marcy I; Faber, Willem D; Kirman, Christopher R; McGregor, Douglas B; Pourreau, Daniel B

    2015-02-01

    A screening level risk assessment has been performed for tertiary-butyl acetate (TBAC) examining its primary uses as a solvent in industrial and consumer products. Hazard quotients (HQ) were developed by merging TBAC animal toxicity and dose-response data with population-level, occupational and consumer exposure scenarios. TBAC has a low order of toxicity following subchronic inhalation exposure, and neurobehavioral changes (hyperactivity) in mice observed immediately after termination of exposure were used as conservative endpoints for derivation of acute and chronic reference concentration (RfC) values. TBAC is not genotoxic but has not been tested for carcinogenicity. However, TBAC is unlikely to be a human carcinogen in that its non-genotoxic metabolic surrogates tertiary-butanol (TBA) and methyl tertiary butyl ether (MTBE) produce only male rat α-2u-globulin-mediated kidney cancer and high-dose specific mouse thyroid tumors, both of which have little qualitative or quantitative relevance to humans. Benchmark dose (BMD)-modeling of the neurobehavioral responses yielded acute and chronic RfC values of 1.5 ppm and 0.3 ppm, respectively. After conservative modeling of general population and near-source occupational and consumer product exposure scenarios, almost all HQs were substantially less than 1. HQs exceeding 1 were limited to consumer use of automotive products and paints in a poorly ventilated garage-sized room (HQ = 313) and occupational exposures in small and large brake shops using no personal protective equipment or ventilation controls (HQs = 3.4-126.6). The screening level risk assessments confirm low human health concerns with most uses of TBAC and indicate that further data-informed refinements can address problematic health/exposure scenarios. The assessments also illustrate how tier-based risk assessments using read-across toxicity information to metabolic surrogates reduce the need for comprehensive animal testing.

  6. Bulk Site Reference Materials

    SciTech Connect

    Barich, J.J. III; Jones, R.R. Sr.

    1996-12-31

    The selection, manufacture and use of Bulk Site Reference Materials (BSRMs) at hazardous waste sites is discussed. BSRMs are useful in preparing stabilization/solidification (S/S) formulations for soils, ranking competing S/S processes, comparing S/S alternatives to other technologies, and in interpreting data from different test types. BSRMs are large volume samples that are representative of the physical and chemical characteristics of a site soil, and that contain contaminants at reasonably high levels. A successful BSRM is extremely homogeneous and well-characterized. While not representative of any point on the site, they contain the contaminants of the site in the matrices of the site. Design objectives for a BSRM are to produce a material that (1) maintains good fidelity to site matrices and contaminants, and (2) exhibits the lowest possible relative standard deviation.

  7. Tank characterization reference guide

    SciTech Connect

    De Lorenzo, D.S.; DiCenso, A.T.; Hiller, D.B.; Johnson, K.W.; Rutherford, J.H.; Smith, D.J.; Simpson, B.C.

    1994-09-01

    Characterization of the Hanford Site high-level waste storage tanks supports safety issue resolution; operations and maintenance requirements; and retrieval, pretreatment, vitrification, and disposal technology development. Technical, historical, and programmatic information about the waste tanks is often scattered among many sources, if it is documented at all. This Tank Characterization Reference Guide, therefore, serves as a common location for much of the generic tank information that is otherwise contained in many documents. The report is intended to be an introduction to the issues and history surrounding the generation, storage, and management of the liquid process wastes, and a presentation of the sampling, analysis, and modeling activities that support the current waste characterization. This report should provide a basis upon which those unfamiliar with the Hanford Site tank farms can start their research.

  8. International reference standards in coagulation.

    PubMed

    Raut, Sanj; Hubbard, Anthony R

    2010-07-01

    Measurement of coagulation factor activity using absolute physico-chemical techniques is not possible and estimation therefore relies on comparative bioassay relative to a reference standard with a known or assigned potency. However the inherent variability of locally prepared and calibrated reference standards can give rise to poor agreement between laboratories and methods. Harmonisation of measurement between laboratories at the international level relies on the availability of a common source of calibration for local reference standards and this is provided by the World Health Organization (WHO) International Standards which define the International Unit for the analyte. This article describes the principles, practices and problems of biological standardisation and the development and use of reference standards for assays of coagulation factors, with particular emphasis on WHO International Standards for both concentrates and plasma.

  9. Application of the hybrid approach to the benchmark dose of urinary cadmium as the reference level for renal effects in cadmium polluted and non-polluted areas in Japan

    SciTech Connect

    Suwazono, Yasushi; Nogawa, Kazuhiro; Uetani, Mirei; Nakada, Satoru; Kido, Teruhiko; Nakagawa, Hideaki

    2011-02-15

    Objectives: The aim of this study was to evaluate the reference level of urinary cadmium (Cd) that caused renal effects. An updated hybrid approach was used to estimate the benchmark doses (BMDs) and their 95% lower confidence limits (BMDL) in subjects with a wide range of exposure to Cd. Methods: The total number of subjects was 1509 (650 men and 859 women) in non-polluted areas and 3103 (1397 men and 1706 women) in the environmentally exposed Kakehashi river basin. We measured urinary cadmium (U-Cd) as a marker of long-term exposure, and {beta}2-microglobulin ({beta}2-MG) as a marker of renal effects. The BMD and BMDL that corresponded to an additional risk (BMR) of 5% were calculated with background risk at zero exposure set at 5%. Results: The U-Cd BMDL for {beta}2-MG was 3.5 {mu}g/g creatinine in men and 3.7 {mu}g/g creatinine in women. Conclusions: The BMDL values for a wide range of U-Cd were generally within the range of values measured in non-polluted areas in Japan. This indicated that the hybrid approach is a robust method for different ranges of cadmium exposure. The present results may contribute further to recent discussions on health risk assessment of Cd exposure.

  10. Genetics Home Reference

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Genetics Home Reference Past Issues / Spring 2007 Table of ... of this page please turn Javascript on. The Genetics Home Reference (GHR) Web site — ghr.nlm.nih. ...

  11. Herbal reference standards.

    PubMed

    Schwarz, Michael; Klier, Bernhard; Sievers, Hartwig

    2009-06-01

    This review describes the current definitions and regulatory requirements that apply to reference standards that are used to analyse herbal products. It also describes and discusses the current use of reference substances and reference extracts in the European and United States pharmacopoeias.

  12. Academic Library Reference Services.

    ERIC Educational Resources Information Center

    Batt, Fred

    This examination of the philosophy and objectives of academic library reference services provides an overview of the major reference approaches to fulfilling the following primary objectives of reference services: (1) providing accurate answers to patrons' questions and/or helping patrons find sources to pursue their research needs; (2) building…

  13. References for marine science

    NASA Astrophysics Data System (ADS)

    1990-06-01

    Standard and Reference Materials for Marine Science, National Oceanic and Atmospheric Administration Technical Memo OMA-51 (2nd edition, 434 pp.), by A. Y. Cantillo, is now available. This compilation of reference materials was prepared at the request of the Group of Experts on Standards and Reference Materials and was printed by NOAA. GESREM is sponsored by the International Atomic Energy Agency, the Intergovernmental Oceanographic Commission, and the United Nations Program.Reference materials are included on ashes, gases, instrument performance materials, oils, physical properties, rocks, sediments, sludges, tissues and waters. For each reference material, source, description and preparation, analyses and values, cost, references, and comments are given. Indices are included for elements, isotopes and organic compounds. Cross references to Chemical Abstracts Service registry numbers and alternate names and chemical structures of organic compounds are also provided.

  14. Minimize reference sideband generation in microwave PLLs

    NASA Astrophysics Data System (ADS)

    Goldman, Stan

    1991-02-01

    The processes responsible for producing reference sidebands are outlined, and the sources of coupling to the microwave voltage-controlled oscillator (VCO) tune line including power-supply-generated signals, TTL-controlled interface signals, intermediate programmable-divider signals, and radiated TTL signals are discussed. It is noted that filtering alone is inadequate for reference-sideband suppression, while minimizing the tuning slope and maximizing the reference frequency will result in a reduced reference-sideband level. Minimizing offset currents by using a differential amplifier connection may reduce the reference-sideband level aggravated by an opamp. The selection of a TTL, ECL, or GaAs phase/frequency detector can determine the level of reference sidebands, as well as PCB isolation techniques.

  15. Current density in a model of a human body with a conductive implant exposed to ELF electric and magnetic fields.

    PubMed

    Valic, Blaz; Gajsek, Peter; Miklavcic, Damijan

    2009-10-01

    A numerical model of a human body with an intramedullary nail in the femur was built to evaluate the effects of the implant on the current density distribution in extremely low frequency electric and magnetic fields. The intramedullary nail was chosen because it is one of the longest high conductive implants used in the human body. As such it is expected to alter the electric and magnetic fields significantly. The exposure was a simultaneous combination of inferior to superior electric field and posterior to anterior magnetic field both alternating at 50 Hz with the values corresponding to the ICNIRP reference levels: 5000 V m(-1) for electric field and 100 microT for magnetic flux density. The calculated current density distribution inside the model was compared to the ICNIRP basic restrictions for general public (2 mA m(-2)). The results show that the implant significantly increases the current density up to 9.5 mA m(-2) in the region where it is in contact with soft tissue in the model with the implant in comparison to 0.9 mA m(-2) in the model without the implant. As demonstrated the ICNIRP basic restrictions are exceeded in a limited volume of the tissue in spite of the compliance with the ICNIRP reference levels for general public, meaning that the existing safety limits do not necessarily protect implanted persons to the same extent as they protect people without implants.

  16. High frequency reference electrode

    DOEpatents

    Kronberg, James W.

    1994-01-01

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or "halo" at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

  17. High frequency reference electrode

    DOEpatents

    Kronberg, J.W.

    1994-05-31

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes. 4 figs.

  18. Preparing the references.

    PubMed

    Peh, W C G; Ng, K H

    2009-07-01

    In a scientific paper, the references serve to provide background information and allow the researcher to compare and contrast the work of others in relation to his own study. Authors are responsible for the accuracy of all references cited. The references quoted should be easily accessible and retrievable by anyone wishing to obtain further information. There is a strong preference for citing journal articles listed in PubMed. The two major reference format systems are the Vancouver and Harvard systems, with increasing preference for the Vancouver system. Authors should adhere exactly to the instructions to authors of the target journal.

  19. Marketing Reference Services.

    ERIC Educational Resources Information Center

    Norman, O. Gene

    1995-01-01

    Relates the marketing concept to library reference services. Highlights include a review of the literature and an overview of marketing, including research, the marketing mix, strategic plan, marketing plan, and marketing audit. Marketing principles are applied to reference services through the marketing mix elements of product, price, place, and…

  20. An Online Reference System.

    ERIC Educational Resources Information Center

    Chisman, Janet; Treat, William

    1984-01-01

    Describes a computer aid developed to assist in academic library reference service using the DataPhase Circulation System, an automated system that features full cataloging records in database and permits local programing. Access points (subject, type of reference work, course) and database structure and user screens are highlighted. (EJS)

  1. China Connections Reference Book.

    ERIC Educational Resources Information Center

    Kalat, Marie B.; Hoermann, Elizabeth F.

    This reference book focuses on six aspects of the geography of the People's Republic of China. They are: territory, governing units, population and land use, waterways, land forms, and climates. Designed as a primary reference, the book explains how the Chinese people and their lifestyles are affected by China's geography. Special components…

  2. Rethinking Virtual Reference

    ERIC Educational Resources Information Center

    Tenopir, Carol

    2004-01-01

    Virtual reference services seem a natural extension of libraries digital collections and the emphasis on access to the library anytime, anywhere. If patrons use the library from home, it makes sense to provide them with person-to-person online reference. The Library of Congress (LC), OCLC, and several large library systems have developed and…

  3. A standard satellite control reference model

    NASA Technical Reports Server (NTRS)

    Golden, Constance

    1994-01-01

    This paper describes a Satellite Control Reference Model that provides the basis for an approach to identify where standards would be beneficial in supporting space operations functions. The background and context for the development of the model and the approach are described. A process for using this reference model to trace top level interoperability directives to specific sets of engineering interface standards that must be implemented to meet these directives is discussed. Issues in developing a 'universal' reference model are also identified.

  4. [Dietary reference intakes of phosphorus].

    PubMed

    Uenishi, Kazuhiro

    2012-10-01

    Phosphorus (P) exists at the all organs and plays important physiological roles in the body. A wide range of food contains P, which is absorbed at a higher level (60-70%) and its insufficiency and deficiency are rarely found. P is used as food additives in many processed food, where risk of overconsumption could be an issue. P has less evidence in terms of nutrition. P has the adequate intake and the tolerable upper intake level, for risk reduction of health disorders associated with excess intake, at the Dietary Reference Intakes for Japanese (2010 edition).

  5. Reach for Reference. Grolier's The Civil War

    ERIC Educational Resources Information Center

    Safford, Barbara Ripp

    2005-01-01

    This column describes Grolier's new ten-volume reference set, "The Civil War." The volumes are easy to handle and the set's appearance is designed to appeal to middle level students. Arrangement is alphabetical from Abolition in volume one to Zouaves in volume ten with reasonable cross references to other relevant articles. Each volume contains a…

  6. Genetics Home Reference: nephronophthisis

    MedlinePlus

    ... these are often referred to as nephronophthisis -associated ciliopathies. For example, Senior-Løken syndrome is characterized by ... Nephronophthisis Patient Support and Advocacy Resources (2 links) Ciliopathy Alliance National Kidney Foundation GeneReviews (1 link) Nephronophthisis ...

  7. Value of Information References

    SciTech Connect

    Morency, Christina

    2014-12-12

    This file contains a list of relevant references on value of information (VOI) in RIS format. VOI provides a quantitative analysis to evaluate the outcome of the combined technologies (seismology, hydrology, geodesy) used to monitor Brady's Geothermal Field.

  8. Selecting a reference object.

    PubMed

    Miller, Jared E; Carlson, Laura A; Hill, Patrick L

    2011-07-01

    One way to describe the location of an object is to relate it to another object. Often there are many nearby objects, each of which could serve as a candidate to be the reference object. A common theoretical assumption is that features that make a given object salient relative to the candidate set are instrumental in determining which is selected. The current research tests this assumption, assessing the relative importance of spatial, perceptual, and functional-interactive features. Three experiments demonstrated that spatial features have the strongest influence on reference object selection, with the perceptual feature of color playing no significant role. Functional-interactive features were shown to be spatially dependent, having an influence only when the spatial configuration enabled an interaction between the located object and the reference object. These findings challenge the common perspective that salience in and of itself dictates reference object selection and argue for a reliance on spatial features.

  9. Genetics Home Reference

    MedlinePlus

    ... MENU Toggle navigation Home Page Search Share: Email Facebook Twitter Home Health Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Genetics Home Reference provides consumer-friendly information about the effects of genetic variation ...

  10. Enterprise Reference Library

    NASA Technical Reports Server (NTRS)

    Bickham, Grandin; Saile, Lynn; Havelka, Jacque; Fitts, Mary

    2011-01-01

    Introduction: Johnson Space Center (JSC) offers two extensive libraries that contain journals, research literature and electronic resources. Searching capabilities are available to those individuals residing onsite or through a librarian s search. Many individuals have rich collections of references, but no mechanisms to share reference libraries across researchers, projects, or directorates exist. Likewise, information regarding which references are provided to which individuals is not available, resulting in duplicate requests, redundant labor costs and associated copying fees. In addition, this tends to limit collaboration between colleagues and promotes the establishment of individual, unshared silos of information The Integrated Medical Model (IMM) team has utilized a centralized reference management tool during the development, test, and operational phases of this project. The Enterprise Reference Library project expands the capabilities developed for IMM to address the above issues and enhance collaboration across JSC. Method: After significant market analysis for a multi-user reference management tool, no available commercial tool was found to meet this need, so a software program was built around a commercial tool, Reference Manager 12 by The Thomson Corporation. A use case approach guided the requirements development phase. The premise of the design is that individuals use their own reference management software and export to SharePoint when their library is incorporated into the Enterprise Reference Library. This results in a searchable user-specific library application. An accompanying share folder will warehouse the electronic full-text articles, which allows the global user community to access full -text articles. Discussion: An enterprise reference library solution can provide a multidisciplinary collection of full text articles. This approach improves efficiency in obtaining and storing reference material while greatly reducing labor, purchasing and

  11. Membrane reference electrode

    DOEpatents

    Redey, L.; Bloom, I.D.

    1988-01-21

    A reference electrode utilizes a small thin, flat membrane of a highly conductive glass placed on a small diameter insulator tube having a reference material inside in contact with an internal voltage lead. When the sensor is placed in a non-aqueous ionic electrolytic solution, the concentration difference across the glass membrane generates a low voltage signal in precise relationship to the concentration of the species to be measured, with high spatial resolution. 2 figs.

  12. Membrane reference electrode

    DOEpatents

    Redey, Laszlo; Bloom, Ira D.

    1989-01-01

    A reference electrode utilizes a small thin, flat membrane of a highly conductive glass placed on a small diameter insulator tube having a reference material inside in contact with an internal voltage lead. When the sensor is placed in a non-aqueous ionic electrolytic solution, the concentration difference across the glass membrane generates a low voltage signal in precise relationship to the concentration of the species to be measured with high spatial resolution.

  13. Precision displacement reference system

    DOEpatents

    Bieg, Lothar F.; Dubois, Robert R.; Strother, Jerry D.

    2000-02-22

    A precision displacement reference system is described, which enables real time accountability over the applied displacement feedback system to precision machine tools, positioning mechanisms, motion devices, and related operations. As independent measurements of tool location is taken by a displacement feedback system, a rotating reference disk compares feedback counts with performed motion. These measurements are compared to characterize and analyze real time mechanical and control performance during operation.

  14. Reference Man anatomical model

    SciTech Connect

    Cristy, M.

    1994-10-01

    The 70-kg Standard Man or Reference Man has been used in physiological models since at least the 1920s to represent adult males. It came into use in radiation protection in the late 1940s and was developed extensively during the 1950s and used by the International Commission on Radiological Protection (ICRP) in its Publication 2 in 1959. The current Reference Man for Purposes of Radiation Protection is a monumental book published in 1975 by the ICRP as ICRP Publication 23. It has a wealth of information useful for radiation dosimetry, including anatomical and physiological data, gross and elemental composition of the body and organs and tissues of the body. The anatomical data includes specified reference values for an adult male and an adult female. Other reference values are primarily for the adult male. The anatomical data include much data on fetuses and children, although reference values are not established. There is an ICRP task group currently working on revising selected parts of the Reference Man document.

  15. Genetics Home Reference: fish-eye disease

    MedlinePlus

    ... levels of HDL cholesterol and atherosclerosis, a variable relationship--a review of LCAT deficiency. Vasc Health Risk ... healthcare professional . About Genetics Home Reference Site Map Customer Support Selection Criteria for Links USA.gov Copyright ...

  16. Genetics Home Reference: complete LCAT deficiency

    MedlinePlus

    ... levels of HDL cholesterol and atherosclerosis, a variable relationship--a review of LCAT deficiency. Vasc Health Risk ... healthcare professional . About Genetics Home Reference Site Map Customer Support Selection Criteria for Links USA.gov Copyright ...

  17. Microgrid cyber security reference architecture.

    SciTech Connect

    Veitch, Cynthia K.; Henry, Jordan M.; Richardson, Bryan T.; Hart, Derek H.

    2013-07-01

    This document describes a microgrid cyber security reference architecture. First, we present a high-level concept of operations for a microgrid, including operational modes, necessary power actors, and the communication protocols typically employed. We then describe our motivation for designing a secure microgrid; in particular, we provide general network and industrial control system (ICS)-speci c vulnerabilities, a threat model, information assurance compliance concerns, and design criteria for a microgrid control system network. Our design approach addresses these concerns by segmenting the microgrid control system network into enclaves, grouping enclaves into functional domains, and describing actor communication using data exchange attributes. We describe cyber actors that can help mitigate potential vulnerabilities, in addition to performance bene ts and vulnerability mitigation that may be realized using this reference architecture. To illustrate our design approach, we present a notional a microgrid control system network implementation, including types of communica- tion occurring on that network, example data exchange attributes for actors in the network, an example of how the network can be segmented to create enclaves and functional domains, and how cyber actors can be used to enforce network segmentation and provide the neces- sary level of security. Finally, we describe areas of focus for the further development of the reference architecture.

  18. Writing More Informative Letters of Reference

    PubMed Central

    Wright, Scott M; Ziegelstein, Roy C

    2004-01-01

    Writing a meaningful and valuable letter of reference is not an easy task. Several factors influence the quality of any letter of reference. First, the accuracy and reliability of the writer's impressions and judgment depend on how well he knows the individual being described. Second, the writer's frame of reference, which is determined by the number of persons at the same level that he has worked with, will impact the context and significance of his beliefs and estimations. Third, the letter-writing skills of the person composing the letter will naturally affect the letter. To support the other components of a candidate's application, a letter of reference should provide specific examples of how an individual's behavior or attitude compares to a reference group and should assess “intangibles” that are hard to glean from a curriculum vitae or from test scores. This report offers suggestions that should help physicians write more informative letters of reference. PMID:15109330

  19. Setting reference targets

    SciTech Connect

    Ruland, R.E.

    1997-04-01

    Reference Targets are used to represent virtual quantities like the magnetic axis of a magnet or the definition of a coordinate system. To explain the function of reference targets in the sequence of the alignment process, this paper will first briefly discuss the geometry of the trajectory design space and of the surveying space, then continue with an overview of a typical alignment process. This is followed by a discussion on magnet fiducialization. While the magnetic measurement methods to determine the magnetic centerline are only listed (they will be discussed in detail in a subsequent talk), emphasis is given to the optical/mechanical methods and to the task of transferring the centerline position to reference targets.

  20. Multifunctional reference electrode

    DOEpatents

    Redey, L.; Vissers, D.R.

    1981-12-30

    A multifunctional, low mass reference electrode of a nickel tube, thermocouple means inside the nickel tube electrically insulated therefrom for measuring the temperature thereof, a housing surrounding the nickel tube, an electrolyte having a fixed sulfide ion activity between the housing and the outer surface of the nickel tube forming the nickel/nickel sulfide/sulfide half-cell are described. An ion diffusion barrier is associated with the housing in contact with the electrolyte. Also disclosed is a cell using the reference electrode to measure characteristics of a working electrode.

  1. Multifunctional reference electrode

    DOEpatents

    Redey, Laszlo; Vissers, Donald R.

    1983-01-01

    A multifunctional, low mass reference electrode of a nickel tube, thermocouple means inside the nickel tube electrically insulated therefrom for measuring the temperature thereof, a housing surrounding the nickel tube, an electrolyte having a fixed sulfide ion activity between the housing and the outer surface of the nickel tube forming the nickel/nickel sulfide/sulfide half-cell. An ion diffusion barrier is associated with the housing in contact with the electrolyte. Also disclosed is a cell using the reference electrode to measure characteristics of a working electrode.

  2. IERS Reference System.

    NASA Astrophysics Data System (ADS)

    Yokoyama, K.

    Present circumstances related to IERS activities are described from various points of view. The NASA Dynamics of Solid Earth (DOSE) program and the IERS intensive campaign proposed by J. Dickey of JPL are particularly interesting. It is important to implement international cooperation to establish a fundamental radio reference frame by carrying out global solution based on all geodetic observations, past and future. A precession and nutation model may be determined observationally with an accuracy of 0.2 - 0.3 mas in a few years. Then it will become possible to establish the radio reference frame with this accuracy.

  3. Aluminum reference electrode

    DOEpatents

    Sadoway, D.R.

    1988-08-16

    A stable reference electrode is described for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na[sub 3]AlF[sub 6], wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution. 1 fig.

  4. Aluminum reference electrode

    DOEpatents

    Sadoway, Donald R.

    1988-01-01

    A stable reference electrode for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na.sub.3 AlF.sub.6, wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution.

  5. NASCAP programmer's reference manual

    NASA Technical Reports Server (NTRS)

    Mandell, M. J.; Stannard, P. R.; Katz, I.

    1993-01-01

    The NASA Charging Analyzer Program (NASCAP) is a computer program designed to model the electrostatic charging of complicated three-dimensional objects, both in a test tank and at geosynchronous altitudes. This document is a programmer's reference manual and user's guide. It is designed as a reference to experienced users of the code, as well as an introduction to its use for beginners. All of the many capabilities of NASCAP are covered in detail, together with examples of their use. These include the definition of objects, plasma environments, potential calculations, particle emission and detection simulations, and charging analysis.

  6. Particulate matter (PM) 2.5 levels in ETS emissions of a Marlboro Red cigarette in comparison to the 3R4F reference cigarette under open- and closed-door condition

    PubMed Central

    2012-01-01

    Introduction Potential health damage by environmental emission of tobacco smoke (environmental tobacco smoke, ETS) has been demonstrated convincingly in numerous studies. People, especially children, are still exposed to ETS in the small space of private cars. Although major amounts of toxic compounds from ETS are likely transported into the distal lung via particulate matter (PM), few studies have quantified the amount of PM in ETS. Study aim The aim of this study was to determine the ETS-dependent concentration of PM from both a 3R4F reference cigarette (RC) as well as a Marlboro Red brand cigarette (MRC) in a small enclosed space under different conditions of ventilation to model car exposure. Method In order to create ETS reproducibly, an emitter (ETSE) was constructed and mounted on to an outdoor telephone booth with an inner volume of 1.75 m3. Cigarettes were smoked under open- and closed-door condition to imitate different ventilation scenarios. PM2.5 concentration was quantified by a laser aerosol spectrometer (Grimm; Model 1.109), and data were adjusted for baseline values. Simultaneously indoor and outdoor climate parameters were recorded. The time of smoking was divided into the ETS generation phase (subset “emission”) and a declining phase of PM concentration (subset “elimination”); measurement was terminated after 10 min. For all three time periods the average concentration of PM2.5 (Cmean-PM2.5) and the area under the PM2.5 concentration curve (AUC-PM2.5) was calculated. The maximum concentration (Cmax-PM2.5) was taken from the total interval. Results For both cigarette types open-door ventilation reduced the AUC-PM2.5 (RC: from 59 400 ± 14 600 to 5 550 ± 3 900 μg*sec/m3; MRC: from 86 500 ± 32 000 to 7 300 ± 2 400 μg*sec/m3; p < 0.001) and Cmean-PM2.5 (RC: from 600 ± 150 to 56 ± 40 μg/m3, MRC from 870 ± 320 to 75 ± 25 μg/m3; p < 0.001) by about 90%. Cmax-PM2.5 was reduced by about 80% (RC

  7. Multimedia Reference Tools.

    ERIC Educational Resources Information Center

    Holzberg, Carol S.

    2001-01-01

    Presents suggestions for content-rich classroom encyclopedias on CO-ROM and DVD, including: the Encarta Reference Suite 2001; the 2001 Grolier Multimedia Encyclopedia, School Edition; the Britannica 2001 DVD; and the World Book 2001 Deluxe Edition, v5.0. (SM)

  8. Digital Reference Service.

    ERIC Educational Resources Information Center

    Mon, Lorri

    2000-01-01

    Discusses the increasing demand for digital reference services from government Web sites via email, and describes a partnership between the Government Printing Office and the federal depository library at the University of Illinois at Chicago to create electronic access to the Department of State Foreign Affairs Network (DOSFAN). (Author/LRW)

  9. Reflections on Reference Services.

    ERIC Educational Resources Information Center

    Brandt, Kerryn A.; And Others

    1996-01-01

    Describes programmatic changes in reference services at the Johns Hopkins University (Maryland) medical library and speculates on the future. Topics include institutional restructuring and consolidation; improvements in technology infrastructure; external economic pressure; and fiscal accountability, including library funding and cost center…

  10. Questions in Reference Interviews.

    ERIC Educational Resources Information Center

    White, Marilyn Domas

    1998-01-01

    Characterizes the questioning behavior in reference interviews preceding delegated online searches of bibliographic databases and relates it to questioning behavior in other types of interviews/settings. Compares questions asked by the information specialist and those asked by the client; findings show the information specialist dominates the…

  11. The Reference Encounter Model.

    ERIC Educational Resources Information Center

    White, Marilyn Domas

    1983-01-01

    Develops model of the reference interview which explicitly incorporates human information processing, particularly schema ideas presented by Marvin Minsky and other theorists in cognitive processing and artificial intelligence. Questions are raised concerning use of content analysis of transcribed verbal protocols as methodology for studying…

  12. Reference-Dependent Sympathy

    ERIC Educational Resources Information Center

    Small, Deborah A.

    2010-01-01

    Natural disasters and other traumatic events often draw a greater charitable response than do ongoing misfortunes, even those that may cause even more widespread misery, such as famine or malaria. Why is the response disproportionate to need? The notion of reference dependence critical to Prospect Theory (Kahneman & Tversky, 1979) maintains that…

  13. Virtual Reference Services.

    ERIC Educational Resources Information Center

    Brewer, Sally

    2003-01-01

    As the need to access information increases, school librarians must create virtual libraries. Linked to reliable reference resources, the virtual library extends the physical collection and library hours and lets students learn to use Web-based resources in a protected learning environment. The growing number of virtual schools increases the need…

  14. Reference Collections and Standards.

    ERIC Educational Resources Information Center

    Winkel, Lois

    1999-01-01

    Reviews six reference materials for young people: "The New York Public Library Kid's Guide to Research"; "National Audubon Society First Field Guide. Mammals"; "Star Wars: The Visual Dictionary"; "Encarta Africana"; "World Fact Book, 1998"; and "Factastic Book of 1001 Lists". Includes ordering information.(AEF)

  15. A GUJARATI REFERENCE GRAMMAR.

    ERIC Educational Resources Information Center

    CARDONA, GEORGE

    THIS REFERENCE GRAMMAR WAS WRITTEN TO FILL THE NEED FOR AN UP-TO-DATE ANALYSIS OF THE MODERN LANGUAGE SUITABLE FOR LANGUAGE LEARNERS AS WELL AS LINGUISTS. THE AUTHOR LISTS IN THE INTRODUCTION THOSE STUDIES PREVIOUS TO THIS ONE WHICH MAY BE OF INTEREST TO THE READER. INCLUDED IN HIS ANALYSIS OF THE LANGUAGE ARE MAJOR CHAPTERS ON--(1) PHONOLOGY, (2)…

  16. Reference Sources for Nursing

    ERIC Educational Resources Information Center

    Nursing Outlook, 1976

    1976-01-01

    The ninth revision (including a Canadian supplement) of a list of nursing reference works lists items in the following sections: abstract journals, audiovisuals, bibliographies, dictionaries, directories, drug lists and pharmacologies, educational programs, histories, indexes, legal guides, library administration and organization, research grants,…

  17. Reference Sources for Nursing

    ERIC Educational Resources Information Center

    Nursing Outlook, 1978

    1978-01-01

    The tenth revision of a list of reference works for nurses, revised by a committee of the Interagency Council on Library Resources for Nursing, listed by type of publication as abstract journals, audiovisuals, bibliographies, books, dictionaries, directories, pharmacologies, indexes, guides, and so on. (MF)

  18. Selecting a Reference Object

    ERIC Educational Resources Information Center

    Miller, Jared E.; Carlson, Laura A.; Hill, Patrick L.

    2011-01-01

    One way to describe the location of an object is to relate it to another object. Often there are many nearby objects, each of which could serve as a candidate to be the reference object. A common theoretical assumption is that features that make a given object salient relative to the candidate set are instrumental in determining which is selected.…

  19. Isotope reference materials

    USGS Publications Warehouse

    Coplen, Tyler B.

    2010-01-01

    Measurement of the same isotopically homogeneous sample by any laboratory worldwide should yield the same isotopic composition within analytical uncertainty. International distribution of light element isotopic reference materials by the International Atomic Energy Agency and the U.S. National Institute of Standards and Technology enable laboratories to achieve this goal.

  20. Reference Model Development

    SciTech Connect

    Jepsen, Richard

    2011-11-02

    Presentation from the 2011 Water Peer Review in which principal investigator discusses project progress to develop a representative set of Reference Models (RM) for the MHK industry to develop baseline cost of energy (COE) and evaluate key cost component/system reduction pathways.

  1. Hospitality Services Reference Book.

    ERIC Educational Resources Information Center

    Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

    This reference book provides information needed by employees in hospitality services occupations. It includes 29 chapters that cover the following topics: the hospitality services industry; professional ethics; organization and management structures; safety practices and emergency procedures; technology; property maintenance and repair; purchasing…

  2. An Amharic Reference Grammar.

    ERIC Educational Resources Information Center

    Leslau, Wolf

    This reference grammar presents a structural description of the orthography, phonology, morphology, and syntax of Amharic, the national language of Ethiopia. The Amharic material in this work, designed to prepare the student for speaking and reading the language, appears in both Amharic script and phonetic transcription. See ED 012 044-5 for the…

  3. The Unreliability of References

    ERIC Educational Resources Information Center

    Barden, Dennis M.

    2008-01-01

    When search consultants, like the author, are invited to propose their services in support of a college or university seeking new leadership, they are generally asked a fairly standard set of questions. But there is one question that they find among the most difficult to answer: How do they check a candidate's references to ensure that they know…

  4. Generating Multimodal References

    ERIC Educational Resources Information Center

    van der Sluis, Ielka; Krahmer, Emiel

    2007-01-01

    This article presents a new computational model for the generation of multimodal referring expressions (REs), based on observations in human communication. The algorithm is an extension of the graph-based algorithm proposed by Krahmer, van Erk, and Verleg (2003) and makes use of a so-called Flashlight Model for pointing. The Flashlight Model…

  5. International reference ionosphere 1990

    NASA Technical Reports Server (NTRS)

    Bilitza, Dieter; Rawer, K.; Bossy, L.; Kutiev, I.; Oyama, K.-I.; Leitinger, R.; Kazimirovsky, E.

    1990-01-01

    The International Reference Ionosphere 1990 (IRI-90) is described. IRI described monthly averages of the electron density, electron temperature, ion temperature, and ion composition in the altitude range from 50 to 1000 km for magnetically quiet conditions in the non-auroral ionosphere. The most important improvements and new developments are summarized.

  6. Reference materials for new psychoactive substances.

    PubMed

    Archer, Roland P; Treble, Ric; Williams, Keith

    2011-01-01

    Historically, the appearance of new psychoactive materials (and hence the requirement for new reference standards) has been relatively slow. This position has now changed, with 101 new psychoactive substances reported to EMCDDA-Europol since 2006. The newly reported materials, and associated metabolites, require properly certified reference materials to permit reliable identification and quantification. The traditional approach and timescales of reference material production and certification are being increasingly challenged by the appearance of these new substances. Reference material suppliers have to adopt new strategies to meet the needs of laboratories. This situation is particularly challenging for toxicology standards as the metabolism of many of these substances is initially unknown. Reference material production often involves synthesis from first principles. While it is possible to synthesis these materials, there can be significant difficulties, from synthetic complexities through to the need to use controlled materials. These issues are examined through a discussion of the synthesis of cathinones. Use of alternative sources, including pharmaceutical impurity materials or internet sourced products, as starting materials for conversion into appropriately certified reference materials are also discussed. The sudden appearance and sometimes brief lifetime in the market place of many of these novel legal highs or research chemicals present commercial difficulties for reference material producers. The need for collaboration at all levels is highlighted as essential to rapid identification of requirements for new reference materials. National or international commissioning or support may also be required to permit reference material producers to recover their development costs.

  7. OSH technical reference manual

    SciTech Connect

    Not Available

    1993-11-01

    In an evaluation of the Department of Energy (DOE) Occupational Safety and Health programs for government-owned contractor-operated (GOCO) activities, the Department of Labor`s Occupational Safety and Health Administration (OSHA) recommended a technical information exchange program. The intent was to share written safety and health programs, plans, training manuals, and materials within the entire DOE community. The OSH Technical Reference (OTR) helps support the secretary`s response to the OSHA finding by providing a one-stop resource and referral for technical information that relates to safe operations and practice. It also serves as a technical information exchange tool to reference DOE-wide materials pertinent to specific safety topics and, with some modification, as a training aid. The OTR bridges the gap between general safety documents and very specific requirements documents. It is tailored to the DOE community and incorporates DOE field experience.

  8. Open SHMEM Reference Implementation

    SciTech Connect

    Pritchard, Howard; Curtis, Anthony; Welch, Aaron; Fridley, Andrew

    2016-05-12

    OpenSHMEM is an effort to create a specification for a standardized API for parallel programming in the Partitioned Global Address Space. Along with the specification the project is also creating a reference implementation of the API. This implementation attempts to be portable, to allow it to be deployed in multiple environments, and to be a starting point for implementations targeted to particular hardware platforms. It will also serve as a springboard for future development of the API.

  9. Range Reference Notebook

    DTIC Science & Technology

    2006-10-15

    rifle grenade (inert), tin can lid, 15” tent peg 3 Table FRD-7. Fort Ritchie Sector 3 Representative Examples of Non-MEC Clutter Description 1/2...Appendix B—Indirect Fire Range Examples SITES ( ADI ) Adak Naval Air Facility, AK, Mitt Lake Mortar Range (FRI) Fort Ritchie...example range. B- ADI -1 Indirect-Fire Range,: Adak, AK, Mitt Lake Mortar Range Impact Area Site-Specific References – Adak NAF Foster Wheeler

  10. MSDS sky reference and preamplifier study

    NASA Technical Reports Server (NTRS)

    Larsen, L.; Stewart, S.; Lambeck, P.

    1974-01-01

    The major goals in re-designing the Multispectral Scanner and Data System (MSDS) sky reference are: (1) to remove the sun-elevation angle and aircraft-attitude angle dependence from the solar-sky illumination measurement, and (2) to obtain data on the optical state of the atmosphere. The present sky reference is dependent on solar elevation and provides essentially no information on important atmospheric parameters. Two sky reference designs were tested. One system is built around a hyperbolic mirror and the reflection approach. A second approach to a sky reference utilizes a fish-eye lens to obtain a 180 deg field of view. A detailed re-design of the present sky reference around the fish-eye approach, even with its limitations, is recommended for the MSDS system. A preamplifier study was undertaken to find ways of improving the noise-equivalent reflectance by reducing the noise level for silicon detector channels on the MSDS.

  11. Precision optical reference frequencies

    NASA Astrophysics Data System (ADS)

    Riehle, Fritz; Schnatz, Harald; Zinner, G.; Trebst, Tilmann; Helmcke, Juergen

    1999-05-01

    Optical reference frequencies are provided by lasers of which the frequencies are stabilized to suitable absorption lines. Presently, twelve reference frequencies/wavelengths within the wavelengths range from 243 nm to 10.3 micrometers are recommended by the International Committee of Weights and Measures as references for the realization of the meter and scientific applications. As typical examples, we describe a diode-pumped, frequency doubled YAG-laser stabilized to an absorption line of molecular iodine and a Ca-stabilized laser. The latter one has been developed in two versions, a transportable system utilizing a small beam of thermal Ca atoms and a stationary standard based on laser cooled and trapped Ca atoms. The frequency of the Ca standard based on cold Ca atoms has been measured by a frequency chain allowing a phase-coherent comparison against the primary standard of time and frequency, the caesium clock. Its value is vCa equals 455 986 240 494.13 kHz with a relative standard uncertainty of 2.5 (DOT) 10-13.

  12. Celestial Reference Frames

    NASA Astrophysics Data System (ADS)

    Jacobs, Christopher S.

    2013-03-01

    Concepts and Background: This paper gives an overview of modern celestial reference frames as realized at radio frequencies using the Very Long baseline Interferometry (VLBI) technique. We discuss basic celestial reference frame concepts, desired properties, and uses. We review the networks of antennas used for this work. We briefly discuss the history of the science of astrometry touching upon the discovery of precession, proper motion, nutation, and parallax, and the field of radio astronomy. Building Celestial Frames: Next, we discuss the multi-step process of building a celestial frame: First candidate sources are identified based on point-like properties from single dish radio telescopes surveys. Second, positions are refined using connected element interferometers such as the Very Large Array, and the ATCA. Third, positions of approximately milli-arcsecond (mas) accuracy are determined using intercontinental VLBI surveys. Fourth, sub-mas positions are determined by multiyear programs using intercontinental VLBI. These sub-mas sets of positions are then verified by multiple teams in preparation for release to non-specialists in the form of an official IAU International Celestial Reference Frame (ICRF). The process described above has until recently been largely restricted to work at S/X-band (2.3/8.4 GHz). However, in the last decade sub-mas work has expanded to include celestial frames at K-band (24 GHz), Ka-band (32 GHz), and Q-band (43 GHz). While these frames currently have the disadvantage of far smaller data sets, the astrophysical quality of the sources themselves improves at these higher frequencies and thus make these frequencies attractive for realizations of celestial reference frames. Accordingly, we review progress at these higher frequency bands. Path to the Future: We discuss prospects for celestial reference frames over the next decade. We present an example of an error budget for astrometric VLBI and discuss the budget's use as a tool for

  13. Celestial Reference Frame

    NASA Astrophysics Data System (ADS)

    Jacobs, Christopher S.

    2013-09-01

    Concepts and Background: This paper gives an overview of modern celestial reference frames as realized at radio frequencies using the Very Long baseline Interferometry (VLBI) technique. We discuss basic celestial reference frame concepts, desired properties, and uses. We review the networks of antennas used for this work. We briefly discuss the history of the science of astrometry touching upon the discovery of precession, proper motion, nutation, and parallax, and the field of radio astronomy. Building Celestial Frames: Next, we discuss the multi-step process of building a celestial frame: First candidate sources are identified based on point-like properties from single dish radio telescopes surveys. Second, positions are refined using connected element interferometers such as the Very Large Array, and the ATCA. Third, positions of approximately milli-arcsecond (mas) accuracy are determined using intercontinental VLBI surveys. Fourth, sub-mas positions are determined by multiyear programs using intercontinental VLBI. These sub-mas sets of positions are then verified by multiple teams in preparation for release to non-specialists in the form of an official IAU International Celestial Reference Frame (ICRF). The process described above has until recently been largely restricted to work at S/X-band (2.3/8.4 GHz). However, in the last decade sub-mas work has expanded to include celestial frames at K-band (24 GHz), Ka-band (32 GHz), and Q-band (43 GHz). While these frames currently have the disadvantage of far smaller data sets, the astrophysical quality of the sources themselves improves at these higher frequencies and thus make these frequencies attractive for realizations of celestial reference frames. Accordingly, we review progress at these higher frequency bands. Path to the Future: We discuss prospects for celestial reference frames over the next decade. We present an example of an error budget for astrometric VLBI and discuss the budget's use as a tool for

  14. Urinary {alpha}{sub 1}-microglobulin, {beta}{sub 2}-microglobulin, and retinol-binding protein levels in general populations in Japan with references to cadmium in urine, blood, and 24-hour food duplicates

    SciTech Connect

    Ikeda, Masayuki; Moon, Chan-Seok; Zhang, Zuo-Wen

    1995-07-01

    Possible cadmium (Cd) exposure-associated changes in urinary levels of low-molecular-weight proteins were studied in nonsmoking and nondrinking female members of the general Japanese population (378 subjects with no known occupational heavy metal exposure) who lived at 19 study sites (all without any known environmental heavy metal pollution) in 13 prefectures throughout Japan. The external Cd dose was evaluated in terms of daily Cd intake via food (Cd-F), whereas Cd levels in blood (Cd-B) and urine (Cd-U) were taken as internal dose indicators. When the subjects were classified according to Cd-F into three groups with {open_quotes}low{close_quotes} (20.4 {mu}g/day as a geometric mean of 97 women), {open_quotes}middle{close_quotes} (35.0 {mu}g/day, 120 women) and {open_quotes}high{close_quotes} (67.0 {mu}g/day, 66 women) exposure, both Cd-B and Cd-U increased in parallel with the changes in Cd-F. However, there were no dose-dependent changes in {beta}{sub 2}-microglobulin or retinol-binding protein levels in urine. {alpha}{sub 1}-Microglobulin levels appeared to increase, but the distribution of the cases above the two cutoff levels of 9.6 and 15.8 {mu}g/mg creatinine among the three Cd-F groups did not show any bias. Overall, it was concluded that there was no apparent Cd exposure-associated elevation in urinary low-molecular-weight protein levels in the study population. 41 refs., 2 figs., 7 tabs.

  15. Developing an Agent Systems Reference Architecture

    DTIC Science & Technology

    2010-05-01

    The notion of a reference architecture has different meanings based on the view- points and concerns of the stakeholders. In this work, a reference...functional concept defined by the ASRM and further elaborating actors and invoca- tion points . The intended audience are high-level practitioners who need...execution. Figure 1(a) displays the temporal view of a scenario demonstrating the invocation points of the agent mobility functional con- cept. The

  16. Reference Inflow Characterization for River Resource Reference Model (RM2)

    SciTech Connect

    Neary, Vincent S

    2011-12-01

    Sandia National Laboratory (SNL) is leading an effort to develop reference models for marine and hydrokinetic technologies and wave and current energy resources. This effort will allow the refinement of technology design tools, accurate estimates of a baseline levelized cost of energy (LCoE), and the identification of the main cost drivers that need to be addressed to achieve a competitive LCoE. As part of this effort, Oak Ridge National Laboratory was charged with examining and reporting reference river inflow characteristics for reference model 2 (RM2). Published turbulent flow data from large rivers, a water supply canal and laboratory flumes, are reviewed to determine the range of velocities, turbulence intensities and turbulent stresses acting on hydrokinetic technologies, and also to evaluate the validity of classical models that describe the depth variation of the time-mean velocity and turbulent normal Reynolds stresses. The classical models are found to generally perform well in describing river inflow characteristics. A potential challenge in river inflow characterization, however, is the high variability of depth and flow over the design life of a hydrokinetic device. This variation can have significant effects on the inflow mean velocity and turbulence intensity experienced by stationary and bottom mounted hydrokinetic energy conversion devices, which requires further investigation, but are expected to have minimal effects on surface mounted devices like the vertical axis turbine device designed for RM2. A simple methodology for obtaining an approximate inflow characterization for surface deployed devices is developed using the relation umax=(7/6)V where V is the bulk velocity and umax is assumed to be the near-surface velocity. The application of this expression is recommended for deriving the local inflow velocity acting on the energy extraction planes of the RM2 vertical axis rotors, where V=Q/A can be calculated given a USGS gage flow time

  17. Investigation of changes in brain natriuretic peptide serum levels and its diagnostic value in patients with mild and moderate head trauma, in patients referred to emergency department of Alzahra Hospital, Isfahan, 2013-2014

    PubMed Central

    Azizkhani, Reza; Keshavarz, Es’haq

    2016-01-01

    Background: Head trauma is one of the most common reasons for emergency department (ED) care. Over the past decade, initial management strategies in mild and moderate head trauma have become focused on selective computed tomography (CT) use based upon presence or absence of specific aspects of patient history and/or clinical examination which has received more attention following reports of increased cancer risk from CT scans. Recently changes in serum brain natriuretic peptide (BNP) levels following head trauma have been studied. We investigated the changes in serum levels of BNP in patients with mild and moderate head trauma, in whom the first brain CT scanning was normal. Materials and Methods: This study is a cross-sectional, descriptive research. It was performed in patients with mild and moderate head trauma. Forty-one patients with isolated mild and moderate traumatic brain injury (Glasgow Coma Scale = 9–15) were included. First brain CT scans were obtained during 2 h after ED arrival and the second one after 24 h. Plasma BNP levels were determined using a specific immunoassay system. Results: Twenty-three patients were in Group A (with normal first and second brain CT) and 18 patients in Group B (with normal first and abnormal second brain CT). With P = 0.001, serum BNP level = 9.04 was determined for differentiating two groups. Conclusion: We concluded that serum BNP level is higher in patients with mild and moderate head trauma with delayed pathologic changes in second brain CT relative to patients with mild and moderate head trauma and with normal delayed brain CT. PMID:28217629

  18. Terminal Forecast Reference Notebook.

    DTIC Science & Technology

    1979-11-07

    Figure 18 , Surface Map 1230Z, October 24, 1948). 4I 7Cm 19 (2) During late spring, suuer or early autumn high oells some- times move southward into the...TFRF, is an excellent reference for this subject. 0 06 0070 I.N ATC 1. A- 2 AREAI p/ A-2 AREA I 1. General: Most flights briefed by Det 18 are within or...in close proxi- mity to Area I. For this reason, Det 18 personnel must become extremely knowledgeable of Area I. 2. Location and Background: The ROK

  19. Assessment of physiotherapists' occupational exposure to radiofrequency electromagnetic fields from shortwave and microwave diathermy devices: a literature review.

    PubMed

    Shah, Syed Ghulam Sarwar; Farrow, Alexandra

    2013-01-01

    We reviewed studies reporting the strength of radiofrequency (RF) electromagnetic fields (EMF) in physiotherapists' occupational environment. Studies from academic journals published from January 1990 to June 2010 were identified in nine online bibliographic databases. EMF strength was compared with occupational exposure limits (OELs) recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). In the reviewed studies, EMFs were measured at different distances (range 0.2 m to 6 m) from the console of diathermy devices, electrodes, and cables. For continuous shortwave diathermy (CSWD) (27.12 megahertz, MHz), measurements of EMFs at < 1 m, 1 m, 1.1-1.5 m, and 2 m reported the maximum E field strength as 8197%, 1639%, 295%, and 69%, respectively, and the maximum H field strength as 6250%, 681%, 213%, and 56%, respectively, of the ICNIRP limits for E and H fields for occupational exposure. For pulsed shortwave diathermy (PSWD) (27.12 MHz), EMF measurements at < 1 m, 1 m, and, 1.1-1.5 m showed the maximum E field intensity as 1639%, 175%, and 32%, and the maximum H field strength as 1175%, 968%, and 28%, respectively, of the ICNIRP limits for E and H fields for occupational exposure. For microwave diathermy (MWD) (2.45 gigahertz, GHz), the maximum power density measured at < 1 m, 1 m, 1.1-1.5 m, and 2 m was 200%, <30%, 0.76%, and 0.82%, respectively, of the ICNIRP limit for occupational exposure. RF EMF emissions measured from continuous and pulsed electrotherapeutic diathermy devices may well be higher than OELs at specific distances, i.e., at 1 m, which is currently designated to be a safe distance for physiotherapists. The minimum safe distance for physiotherapists should be revised to at least 2 m for CSWD and 1.5 m for PSWD. The reviewed studies did not provide evidence of exceeding the ICNIRP's reference levels for occupational exposure at 1 m from MWD devices.

  20. Coal data: A reference

    SciTech Connect

    Not Available

    1995-02-01

    This report, Coal Data: A Reference, summarizes basic information on the mining and use of coal, an important source of energy in the US. This report is written for a general audience. The goal is to cover basic material and strike a reasonable compromise between overly generalized statements and detailed analyses. The section ``Supplemental Figures and Tables`` contains statistics, graphs, maps, and other illustrations that show trends, patterns, geographic locations, and similar coal-related information. The section ``Coal Terminology and Related Information`` provides additional information about terms mentioned in the text and introduces some new terms. The last edition of Coal Data: A Reference was published in 1991. The present edition contains updated data as well as expanded reviews and additional information. Added to the text are discussions of coal quality, coal prices, unions, and strikes. The appendix has been expanded to provide statistics on a variety of additional topics, such as: trends in coal production and royalties from Federal and Indian coal leases, hours worked and earnings for coal mine employment, railroad coal shipments and revenues, waterborne coal traffic, coal export loading terminals, utility coal combustion byproducts, and trace elements in coal. The information in this report has been gleaned mainly from the sources in the bibliography. The reader interested in going beyond the scope of this report should consult these sources. The statistics are largely from reports published by the Energy Information Administration.

  1. Sentinel 2 global reference image

    NASA Astrophysics Data System (ADS)

    Dechoz, C.; Poulain, V.; Massera, S.; Languille, F.; Greslou, D.; de Lussy, F.; Gaudel, A.; L'Helguen, C.; Picard, C.; Trémas, T.

    2015-10-01

    Sentinel-2 is a multispectral, high-resolution, optical imaging mission, developed by the European Space Agency (ESA) in the frame of the Copernicus program of the European Commission. In cooperation with ESA, the Centre National d'Etudes Spatiales (CNES) is responsible for the image quality of the project, and will ensure the CAL/VAL commissioning phase. Sentinel-2 mission is devoted the operational monitoring of land and coastal areas, and will provide a continuity of SPOT- and Landsat-type data. Sentinel-2 will also deliver information for emergency services. Launched in 2015 and 2016, there will be a constellation of 2 satellites on a polar sun-synchronous orbit, imaging systematically terrestrial surfaces with a revisit time of 5 days, in 13 spectral bands in visible and shortwave infra-red. Therefore, multi-temporal series of images, taken under the same viewing conditions, will be available. So as to ensure for the multi-temporal registration of the products, specified to be better than 0.3 pixels at 2σ, a Global Reference Image (GRI) will be produced during the CAL/VAL period. This GRI is composed of a set of Sentinel-2 acquisitions, which geometry has been corrected by bundle block adjustment. During L1B processing, Ground Control Points will be taken between this reference image and the sentinel-2 acquisition processed and the geometric model of the image corrected, so as to ensure the good multi-temporal registration. This paper first details the production of the reference during the CALVAL period, and then details the qualification and geolocation performance assessment of the GRI. It finally presents its use in the Level-1 processing chain and gives a first assessment of the multi-temporal registration.

  2. User Satisfaction with Referrals at a Collaborative Virtual Reference Service

    ERIC Educational Resources Information Center

    Kwon, Nahyun

    2006-01-01

    Introduction: This study investigated unmonitored referrals in a nationwide, collaborative chat reference service. Specifically, it examined the extent to which questions are referred, the types of questions that are more likely to be referred than others, and the level of user satisfaction with the referrals in the collaborative chat reference…

  3. Coastwide Reference Monitoring System (CRMS)

    USGS Publications Warehouse

    2010-01-01

    In 1990, the U.S. Congress enacted the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) in response to growing awareness of a land loss crisis in Louisiana. Projects funded by CWPPRA require monitoring and evaluation of project effectiveness, and there is also a need to assess the cumulative effects of all projects to achieve a sustainable coastal environment. In 2003, the Louisiana Office of Coastal Protection and Restoration (OCPR) and the U.S. Geological Survey (USGS) received approval from the CWPPRA Task Force to implement the Coastwide Reference Monitoring System (CRMS) as a mechanism to monitor and evaluate the effectiveness of CWPPRA projects at the project, region, and coastwide levels. The CRMS design implements a multiple reference approach by using aspects of hydrogeomorphic functional assessments and probabilistic sampling. The CRMS program is as dynamic as the coastal habitats it monitors. The program is currently funded through CWPPRA and provides data for a variety of user groups, including resource managers, academics, landowners, and researchers.

  4. Genetics Home Reference: hypercholesterolemia

    MedlinePlus

    ... Changes Mutations in the APOB , LDLR , LDLRAP1 , and PCSK9 genes cause hypercholesterolemia . High blood cholesterol levels typically ... caused by mutations in the APOB , LDLRAP1 , or PCSK9 gene. Changes in the APOB gene result in ...

  5. Genetics Home Reference: histidinemia

    MedlinePlus

    ... condition characterized by elevated blood levels of the amino acid histidine, a building block of most proteins. Histidinemia ... Additional Information & Resources MedlinePlus (2 links) Health Topic: Amino Acid Metabolism Disorders Health Topic: Newborn Screening Genetic and ...

  6. Genetics Home Reference: hyperlysinemia

    MedlinePlus

    ... condition characterized by elevated blood levels of the amino acid lysine, a building block of most proteins. Hyperlysinemia ... Additional Information & Resources MedlinePlus (2 links) Health Topic: Amino Acid Metabolism Disorders Health Topic: Newborn Screening Genetic and ...

  7. Genetics Home Reference: galactosemia

    MedlinePlus

    ... of these critical enzymes allows galactose and related compounds to build up to toxic levels in the ... galactosaemia revisited. J Inherit Metab Dis. 2006 Aug;29(4):516-25. Epub 2006 Jul 11. Review. ...

  8. Molecular biology references.

    PubMed

    2003-05-01

    Many of the units in this manual describe methods and techniques for the cloning, expression, and structural analysis of neural genes and proteins. We assume that users of these protocols have at least some introductory background in recombinant DNA technology (or are working with a collaborator who does); therefore, we have not provided comprehensive coverage of all of these topics, but rather have concentrated on presenting selected techniques that will be of the most interest and use to the general neuroscience laboratory. More comprehensive coverage of these topics can be found in Current Protocols in Molecular Biology (CPMB), which is extensively cross-referenced throughout this manual. These cross-references are summarized in this appendix.

  9. PASCAL/48 reference manual

    NASA Technical Reports Server (NTRS)

    Knight, J. C.; Hamm, R. W.

    1984-01-01

    PASCAL/48 is a programming language for the Intel MCS-48 series of microcomputers. In particular, it can be used with the Intel 8748. It is designed to allow the programmer to control most of the instructions being generated and the allocation of storage. The language can be used instead of ASSEMBLY language in most applications while allowing the user the necessary degree of control over hardware resources. Although it is called PASCAL/48, the language differs in many ways from PASCAL. The program structure and statements of the two languages are similar, but the expression mechanism and data types are different. The PASCAL/48 cross-compiler is written in PASCAL and runs on the CDC CYBER NOS system. It generates object code in Intel hexadecimal format that can be used to program the MCS-48 series of microcomputers. This reference manual defines the language, describes the predeclared procedures, lists error messages, illustrates use, and includes language syntax diagrams.

  10. Long life reference electrode

    DOEpatents

    Yonco, R.M.; Nagy, Z.

    1987-07-30

    An external, reference electrode is provided for long term use with a high temperature, high pressure system. The electrode is arranged in a vertical, electrically insulative tube with an upper portion serving as an electrolyte reservoir and a lower portion in electrolytic communication with the system to be monitored. The lower end portion includes a flow restriction such as a porous plug to limit the electrolyte release into the system. A piston equalized to the system pressure is fitted into the upper portion of the tube to impart a small incremental pressure to the electrolyte. The piston is selected of suitable size and weight to cause only a slight flow of electrolyte through the porous plug into the high pressure system. This prevents contamination of the electrolyte but is of such small flow rate that operating intervals of a month or more can be achieved. 2 figs.

  11. Long life reference electrode

    DOEpatents

    Yonco, R.M.; Nagy, Z.

    1989-04-04

    An external, reference electrode is provided for long term use with a high temperature, high pressure system. The electrode is arranged in a vertical, electrically insulative tube with an upper portion serving as an electrolyte reservoir and a lower portion in electrolytic communication with the system to be monitored. The lower end portion includes a flow restriction such as a porous plug to limit the electrolyte release into the system. A piston equalized to the system pressure is fitted into the upper portion of the tube to impart a small incremental pressure to the electrolyte. The piston is selected of suitable size and weight to cause only a slight flow of electrolyte through the porous plug into the high pressure system. This prevents contamination of the electrolyte but is of such small flow rate that operating intervals of a month or more can be achieved. 2 figs.

  12. Long life reference electrode

    DOEpatents

    Yonco, Robert M.; Nagy, Zoltan

    1989-01-01

    An external, reference electrode is provided for long term use with a high temperature, high pressure system. The electrode is arranged in a vertical, electrically insulative tube with an upper portion serving as an electrolyte reservior and a lower portion in electrolytic communication with the system to be monitored. The lower end portion includes a flow restriction such as a porous plug to limit the electrolyte release into the system. A piston equalized to the system pressure is fitted into the upper portion of the tube to impart a small incremental pressure to the electrolyte. The piston is selected of suitable size and weight to cause only a slight flow of electrolyte through the porous plug into the high pressure system. This prevents contamination of the electrolyte but is of such small flow rate that operating intervals of a month or more can be achieved.

  13. On establishing reference values.

    PubMed Central

    Lumsden, J H; Mullen, K

    1978-01-01

    In order to establish a range of reference values for any characteristic one can use Gaussian or nonparametric techniques, whichever are most appropriate. One has the choice of calculating tolerance intervals or percentile intervals. A tolerance interval is said to contain, say 95% of the population with probability, say 0.90. A percentile interval simply simply calculates the values between which 95% of the observations fall. If the data can be said to have a Gaussian distribution, the same precision can be obtained with smaller sample sizes than using the nonparametric techniques. In some cases, data which are not Gaussian can be transformed into a Gaussian form and hence make use of the more efficient Gaussian techniques. In both cases, the data should be checked for outliers or rogue observations and these should be eliminated if the testing procedure fails to imply that they are an integral part of the data. PMID:688072

  14. Nuclear Science References Database

    SciTech Connect

    Pritychenko, B.; Běták, E.; Singh, B.; Totans, J.

    2014-06-15

    The Nuclear Science References (NSR) database together with its associated Web interface, is the world's only comprehensive source of easily accessible low- and intermediate-energy nuclear physics bibliographic information for more than 210,000 articles since the beginning of nuclear science. The weekly-updated NSR database provides essential support for nuclear data evaluation, compilation and research activities. The principles of the database and Web application development and maintenance are described. Examples of nuclear structure, reaction and decay applications are specifically included. The complete NSR database is freely available at the websites of the National Nuclear Data Center (http://www.nndc.bnl.gov/nsr) and the International Atomic Energy Agency (http://www-nds.iaea.org/nsr)

  15. International Reference Ionosphere -2010

    NASA Astrophysics Data System (ADS)

    Bilitza, Dieter; Reinisch, Bodo

    The International Reference Ionosphere 2010 includes several important improvements and ad-ditions. This presentation introduces these changes and discusses their benefits. The electron and ion density profiles for the bottomside ionosphere will be significantly improved by using more ionosonde data as well as photochemical considerations. As an additional lower iono-sphere parameter IRI-2010 will include the transition height from molecular to cluster ions. At the F2 peak Neural Net models for the peak density and the propagation factor M3000F2, which is related to the F2 peak height, are introduced as new options. At high latitudes the model will benefit from the introduction of auroral oval boundaries and their variation with magnetic activity. Regarding the electron temperature, IRI-2010 now models variations with solar activity. The homepage for the IRI project is at http://IRI.gsfc.nasa.gov/.

  16. Improved reference models for middle atmosphere ozone

    NASA Astrophysics Data System (ADS)

    Keating, G. M.; Pitts, M. C.; Chen, C.

    This paper describes the improvements introduced into the original version of ozone reference model of Keating and Young (1985, 1987) which is to be incorporated in the next COSPAR International Reference Atmosphere (CIRA). The ozone reference model will provide information on the global ozone distribution (including the ozone vertical structure as a function of month and latitude from 25 to 90 km) combining data from five recent satellite experiments: the Nimbus 7 LIMS, Nimbus 7 SBUV, AE-2 Stratospheric Aerosol Gas Experiment (SAGE), Solar Mesosphere Explorer (SME) UV Spectrometer, and SME 1.27 Micron Airglow. The improved version of the reference model uses reprocessed AE-2 SAGE data (sunset) and extends the use of SAGE data from 1981 to the 1981-1983 time period. Comparisons are presented between the results of this ozone model and various nonsatellite measurements at different levels in the middle atmosphere.

  17. SAR in the mother and foetus for RF plane wave irradiation.

    PubMed

    Dimbylow, Peter

    2007-07-07

    This paper describes the finite-difference time-domain calculation of SAR from 20 MHz to 3 GHz in hybrid voxel-mathematical models of the pregnant female. Mathematical models of the developing foetus at 8-, 13-, 26- and 38-week gestation were converted into voxels and combined with the reference adult female model, NAOMI at a resolution of 2 mm. Whole-body averaged SAR in the mother is presented as well as the average over the foetus, over the foetal brain and in 10 g of the foetus. The electric field values required to produce the ICNIRP public exposure restriction of 2 W kg(-1) when averaged over 10 g of the foetus were calculated. Comparison suggests that the ICNIRP public reference level is a conservative predictor of local SAR in the foetus.

  18. Individual external doses below the lowest reference level of 1 mSv per year five years after the 2011 Fukushima nuclear accident among all children in Soma City, Fukushima: A retrospective observational study

    PubMed Central

    Murakami, Michio; Nomura, Shuhei; Morita, Tomohiro; Nishikawa, Yoshitaka; Leppold, Claire; Kato, Shigeaki; Kami, Masahiro

    2017-01-01

    After the 2011 Fukushima Daiichi nuclear power plant accident, little information has been available on individual doses from external exposure among residents living in radioactively contaminated areas near the nuclear plant; in the present study we evaluated yearly changes in the doses from external exposure after the accident and the effects of decontamination on external exposure. This study considered all children less than 16 years of age in Soma City, Fukushima who participated in annual voluntary external exposure screening programs during the five years after the accident (n = 5,363). In total, 14,405 screening results were collected. The median participant age was eight years. The geometric mean levels of annual additional doses from external exposure attributable to the Fukushima accident, decreased each year: 0.60 mSv (range: not detectable (ND)–4.29 mSv), 0.37 mSv (range: ND–3.61 mSv), 0.22 mSv (range: ND–1.44 mSv), 0.20 mSv (range: ND–1.87 mSv), and 0.17 mSv (range: ND–0.85 mSv) in 2011, 2012, 2013, 2014, and 2015, respectively. The proportion of residents with annual additional doses from external exposure of more than 1 mSv dropped from 15.6% in 2011 to zero in 2015. Doses from external exposure decreased more rapidly than those estimated from only physical decay, even in areas without decontamination (which were halved in 395 days from November 15, 2011), presumably due to the weathering effects. While the ratios of geometric mean doses immediately after decontamination to before were slightly lower than those during the same time in areas without decontamination, annual additional doses reduced by decontamination were small (0.04–0.24 mSv in the year of immediately after decontamination was completed). The results of this study showed that the levels of external exposure among Soma residents less than 16 years of age decreased during the five years after the Fukushima Daiichi nuclear power plant accident. Decontamination had only

  19. Individual external doses below the lowest reference level of 1 mSv per year five years after the 2011 Fukushima nuclear accident among all children in Soma City, Fukushima: A retrospective observational study.

    PubMed

    Tsubokura, Masaharu; Murakami, Michio; Nomura, Shuhei; Morita, Tomohiro; Nishikawa, Yoshitaka; Leppold, Claire; Kato, Shigeaki; Kami, Masahiro

    2017-01-01

    After the 2011 Fukushima Daiichi nuclear power plant accident, little information has been available on individual doses from external exposure among residents living in radioactively contaminated areas near the nuclear plant; in the present study we evaluated yearly changes in the doses from external exposure after the accident and the effects of decontamination on external exposure. This study considered all children less than 16 years of age in Soma City, Fukushima who participated in annual voluntary external exposure screening programs during the five years after the accident (n = 5,363). In total, 14,405 screening results were collected. The median participant age was eight years. The geometric mean levels of annual additional doses from external exposure attributable to the Fukushima accident, decreased each year: 0.60 mSv (range: not detectable (ND)-4.29 mSv), 0.37 mSv (range: ND-3.61 mSv), 0.22 mSv (range: ND-1.44 mSv), 0.20 mSv (range: ND-1.87 mSv), and 0.17 mSv (range: ND-0.85 mSv) in 2011, 2012, 2013, 2014, and 2015, respectively. The proportion of residents with annual additional doses from external exposure of more than 1 mSv dropped from 15.6% in 2011 to zero in 2015. Doses from external exposure decreased more rapidly than those estimated from only physical decay, even in areas without decontamination (which were halved in 395 days from November 15, 2011), presumably due to the weathering effects. While the ratios of geometric mean doses immediately after decontamination to before were slightly lower than those during the same time in areas without decontamination, annual additional doses reduced by decontamination were small (0.04-0.24 mSv in the year of immediately after decontamination was completed). The results of this study showed that the levels of external exposure among Soma residents less than 16 years of age decreased during the five years after the Fukushima Daiichi nuclear power plant accident. Decontamination had only limited and

  20. Workplace Ergonomics Reference Guide

    MedlinePlus

    ... vibration from keyboard and other office equipment.  Monitor sound levels to ensure that communication can occur without a great deal of interference from external noise. Health Factors  Maintain a comfortable temperature, good air quality and adequate circulation in your ...

  1. Preliminary reference Earth model

    NASA Astrophysics Data System (ADS)

    Dziewonski, Adam M.; Anderson, Don L.

    1981-06-01

    A large data set consisting of about 1000 normal mode periods, 500 summary travel time observations, 100 normal mode Q values, mass and moment of inertia have been inverted to obtain the radial distribution of elastic properties, Q values and density in the Earth's interior. The data set was supplemented with a special study of 12 years of ISC phase data which yielded an additional 1.75 × 10 6 travel time observations for P and S waves. In order to obtain satisfactory agreement with the entire data set we were required to take into account anelastic dispersion. The introduction of transverse isotropy into the outer 220 km of the mantle was required in order to satisfy the shorter period fundamental toroidal and spheroidal modes. This anisotropy also improved the fit of the larger data set. The horizontal and vertical velocities in the upper mantle differ by 2-4%, both for P and S waves. The mantle below 220 km is not required to be anisotropic. Mantle Rayleigh waves are surprisingly sensitive to compressional velocity in the upper mantle. High S n velocities, low P n velocities and a pronounced low-velocity zone are features of most global inversion models that are suppressed when anisotropy is allowed for in the inversion. The Preliminary Reference Earth Model, PREM, and auxiliary tables showing fits to the data are presented.

  2. Reference change values.

    PubMed

    Fraser, Callum G

    2011-09-30

    Reference change values (RCV) provide objective tools for assessment of the significance of differences in serial results from an individual. The concept is simple and the calculation easy, since all laboratories know their analytical imprecision (CV(A)) and estimates of within-subject biological variation (CV(I)) are available for a large number of quantities. Generally, CV(I) are constant over time, geography, methodology and in health and chronic stable disease. The formula is RCV=2(1/2) · Z · (CV(A)(2) + CV(I)(2))(1/2), where Z is the number of standard deviations appropriate to the probability. Correct interpretation of the semantics describing the clinical use of RCV is vital for selection of the Z-score. Many quantities of clinically importance exist for which good estimates of RCV are unavailable. Derivation of CV(I) may be difficult for such quantities: flair and imagination are required in selecting populations with chronic but stable disease on whom CV(I) can be determined. RCV can be used for delta-checking and auto-verification and laboratory information management systems (LIMS) can be adapted to do this. Recently, log-normal transformation to obtain unidirectional RCV has been used. Gaps in knowledge of RCV still require filling since the need for measures of change is clearly expressed in guidelines.

  3. Sensor Characteristics Reference Guide

    SciTech Connect

    Cree, Johnathan V.; Dansu, A.; Fuhr, P.; Lanzisera, Steven M.; McIntyre, T.; Muehleisen, Ralph T.; Starke, M.; Banerjee, Pranab; Kuruganti, T.; Castello, C.

    2013-04-01

    The Buildings Technologies Office (BTO), within the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy (EERE), is initiating a new program in Sensor and Controls. The vision of this program is: • Buildings operating automatically and continuously at peak energy efficiency over their lifetimes and interoperating effectively with the electric power grid. • Buildings that are self-configuring, self-commissioning, self-learning, self-diagnosing, self-healing, and self-transacting to enable continuous peak performance. • Lower overall building operating costs and higher asset valuation. The overarching goal is to capture 30% energy savings by enhanced management of energy consuming assets and systems through development of cost-effective sensors and controls. One step in achieving this vision is the publication of this Sensor Characteristics Reference Guide. The purpose of the guide is to inform building owners and operators of the current status, capabilities, and limitations of sensor technologies. It is hoped that this guide will aid in the design and procurement process and result in successful implementation of building sensor and control systems. DOE will also use this guide to identify research priorities, develop future specifications for potential market adoption, and provide market clarity through unbiased information

  4. World Reference Center for Arboviruses.

    DTIC Science & Technology

    1977-08-01

    multiple sclerosis . Lyme disease was associated in distribution with Ixodes ticks but the etiologic agent was not isolated. The reference center distributed 566 ampoules of reference sera, viruses, and antigens during 1977; mosquito and vertebrate cell lines were also distributed.

  5. Knowledge Management and Reference Services

    ERIC Educational Resources Information Center

    Gandhi, Smiti

    2004-01-01

    Many corporations are embracing knowledge management (KM) to capture the intellectual capital of their employees. This article focuses on KM applications for reference work in libraries. It defines key concepts of KM, establishes a need for KM for reference services, and reviews various KM initiatives for reference services.

  6. Web Reference: A Virtual Reality.

    ERIC Educational Resources Information Center

    Foster, Janet

    1999-01-01

    Presents ideas and strategies to enhance digital reference services available via the Internet in public libraries. Describes print publications which include Web reference columns; subject guides, both print and online; and the resources of the Internet Public Library and other virtual reference desks. (LRW)

  7. Paraprofessionals at the Reference Desk.

    ERIC Educational Resources Information Center

    Murfin, Marjorie E.; Bunge, Charles A.

    1988-01-01

    Describes a study that compared the quality of reference services provided by reference librarians and paraprofessionals, using patron satisfaction as the measure of success. Factors associated with satisfactory service are identified, and suggestions for the effective use of paraprofessional staff are presented. (4 references) (CLB)

  8. Fundamentals of Managing Reference Collections

    ERIC Educational Resources Information Center

    Singer, Carol A.

    2012-01-01

    Whether a library's reference collection is large or small, it needs constant attention. Singer's book offers information and insight on best practices for reference collection management, no matter the size, and shows why managing without a plan is a recipe for clutter and confusion. In this very practical guide, reference librarians will learn:…

  9. Canadian listeriosis reference service.

    PubMed

    Pagotto, Franco; Ng, Lai-King; Clark, Clifford; Farber, Jeff

    2006-01-01

    Listeria monocytogenes, a psychrotrophic organism capable of growing at refrigeration temperatures, is of major concern in extended shelf life, refrigerated foods. Considering that as much as 80-90% of human listeriosis cases are linked to the ingestion of contaminated food, human cases are predominantly seen in high-risk individuals, including organ-transplant recipients, patients with AIDS and HIV-infected individuals, pregnant women, cancer patients, and the elderly. In 2001, the Canadian Listeriosis Reference Service (LRS) was created by the Bureau of Microbial Hazards (Health Canada) and the National Microbiology Laboratory (now part of the Public Health Agency of Canada). Major goals of the LRS include investigation of listeriosis cases and maintenance of a national collection of isolates. The LRS intends to create a comprehensive molecular epidemiological database of all isolates in Canada for use as a resource for outbreak investigations, research and other microbiological investigations. The PFGE profiles are being established and stored for clinical, food, environmental, and possibly animal strains of L. monocytogenes. The LRS pursues research activities for investigation and implementation of other molecular methods for characterizing L. monocytogenes isolates. Ribotyping, Multi-locus Sequence Typing (MLST), Variable Number of Tandem Repeats (VNTR), Multi-locus virulence sequence typing (MLVA), microarray- based technologies and sequence-based typing schemes, are being investigated on selected diversity sets. The LRS has also used PFGE typing for outbreak investigations. The molecular epidemiological data, timely coordination and exchange of information should help to reduce the incidence of listeriosis in Canada. In Canada, listeriosis is not a national notifiable disease, except for the province of Quebec, where it has been since 1999. The LRS, Canadian Public Health Laboratory Network, and federal epidemiologists are currently working on making human

  10. Gender agreement and multiple referents.

    PubMed

    Finocchiaro, Chiara; Mahon, Bradford Z; Caramazza, Alfonso

    2008-01-01

    We report a new pattern of usage in current, spoken Italian that has implications for both psycholinguistic models of language production and linguistic theories of language change. In Italian, gender agreement is mandatory for both singular and plural nouns. However, when two or more nouns of different grammatical gender appear in a conjoined noun phrase (NP), masculine plural agreement is required. In this study, we combined on-line and off-line methodologies in order to assess the mechanisms involved in gender marking in the context of multiple referents. The results of two pronoun production tasks showed that plural feminine agreement was significantly more difficult than plural masculine agreement. In a separate study using offline judgements of acceptability, we found that agreement violations in Italian are tolerated more readily in the case of feminine conjoined noun phrases (e.g., la mela e la banana 'the:fem apple:fem and the: fem banana: fem') than masculine conjoined noun phrases (e.g., il fiore e il libro 'the:mas flower: mas and the:mas book:mas'). Implications of these results are discussed both at the level of functional architecture within the language production system and at the level of changes in language use.

  11. The Reference Forward Model (RFM)

    NASA Astrophysics Data System (ADS)

    Dudhia, Anu

    2017-01-01

    The Reference Forward Model (RFM) is a general purpose line-by-line radiative transfer model, currently supported by the UK National Centre for Earth Observation. This paper outlines the algorithms used by the RFM, focusing on standard calculations of terrestrial atmospheric infrared spectra followed by a brief summary of some additional capabilities and extensions to microwave wavelengths and extraterrestrial atmospheres. At its most basic level - the 'line-by-line' component - it calculates molecular absorption cross-sections by applying the Voigt lineshape to all transitions up to ±25 cm-1 from line-centre. Alternatively, absorptions can be directly interpolated from various forms of tabulated data. These cross-sections are then used to construct infrared radiance or transmittance spectra for ray paths through homogeneous cells, plane-parallel or circular atmospheres. At a higher level, the RFM can apply instrumental convolutions to simulate measurements from Fourier transform spectrometers. It can also calculate Jacobian spectra and so act as a stand-alone forward model within a retrieval scheme. The RFM is designed for robustness, flexibility and ease-of-use (particularly by the non-expert), and no claims are made for superior accuracy, or indeed novelty, compared to other line-by-line codes. Its main limitations at present are a lack of scattering and simplified modelling of surface reflectance and line-mixing.

  12. Gender agreement and multiple referents

    PubMed Central

    Finocchiaro, Chiara; Mahon, Bradford Z.; Caramazza, Alfonso

    2010-01-01

    We report a new pattern of usage in current, spoken Italian that has implications for both psycholinguistic models of language production and linguistic theories of language change. In Italian, gender agreement is mandatory for both singular and plural nouns. However, when two or more nouns of different grammatical gender appear in a conjoined noun phrase (NP), masculine plural agreement is required. In this study, we combined on-line and off-line methodologies in order to assess the mechanisms involved in gender marking in the context of multiple referents. The results of two pronoun production tasks showed that plural feminine agreement was significantly more difficult than plural masculine agreement. In a separate study using offline judgements of acceptability, we found that agreement violations in Italian are tolerated more readily in the case of feminine conjoined noun phrases (e.g., la mela e la banana ‘the:fem apple:fem and the: fem banana: fem’) than masculine conjoined noun phrases (e.g., il fiore e il libro ‘the:mas flower: mas and the:mas book:mas’). Implications of these results are discussed both at the level of functional architecture within the language production system and at the level of changes in language use.* PMID:21037930

  13. VIEWCACHE: An incremental pointer-base access method for distributed databases. Part 1: The universal index system design document. Part 2: The universal index system low-level design document. Part 3: User's guide. Part 4: Reference manual. Part 5: UIMS test suite

    NASA Technical Reports Server (NTRS)

    Kelley, Steve; Roussopoulos, Nick; Sellis, Timos

    1992-01-01

    The goal of the Universal Index System (UIS), is to provide an easy-to-use and reliable interface to many different kinds of database systems. The impetus for this system was to simplify database index management for users, thus encouraging the use of indexes. As the idea grew into an actual system design, the concept of increasing database performance by facilitating the use of time-saving techniques at the user level became a theme for the project. This Final Report describes the Design, the Implementation of UIS, and its Language Interfaces. It also includes the User's Guide and the Reference Manual.

  14. Generic Crystalline Disposal Reference Case

    SciTech Connect

    Painter, Scott Leroy; Chu, Shaoping; Harp, Dylan Robert; Perry, Frank Vinton; Wang, Yifeng

    2015-02-20

    A generic reference case for disposal of spent nuclear fuel and high-level radioactive waste in crystalline rock is outlined. The generic cases are intended to support development of disposal system modeling capability by establishing relevant baseline conditions and parameters. Establishment of a generic reference case requires that the emplacement concept, waste inventory, waste form, waste package, backfill/buffer properties, EBS failure scenarios, host rock properties, and biosphere be specified. The focus in this report is on those elements that are unique to crystalline disposal, especially the geosphere representation. Three emplacement concepts are suggested for further analyses: a waste packages containing 4 PWR assemblies emplaced in boreholes in the floors of tunnels (KBS-3 concept), a 12-assembly waste package emplaced in tunnels, and a 32-assembly dual purpose canister emplaced in tunnels. In addition, three failure scenarios were suggested for future use: a nominal scenario involving corrosion of the waste package in the tunnel emplacement concepts, a manufacturing defect scenario applicable to the KBS-3 concept, and a disruptive glaciation scenario applicable to both emplacement concepts. The computational approaches required to analyze EBS failure and transport processes in a crystalline rock repository are similar to those of argillite/shale, with the most significant difference being that the EBS in a crystalline rock repository will likely experience highly heterogeneous flow rates, which should be represented in the model. The computational approaches required to analyze radionuclide transport in the natural system are very different because of the highly channelized nature of fracture flow. Computational workflows tailored to crystalline rock based on discrete transport pathways extracted from discrete fracture network models are recommended.

  15. Occupational exposure to intermediate frequency and extremely low frequency magnetic fields among personnel working near electronic article surveillance systems.

    PubMed

    Roivainen, Päivi; Eskelinen, Tuomo; Jokela, Kari; Juutilainen, Jukka

    2014-05-01

    Cashiers are potentially exposed to intermediate frequency (IF) magnetic fields at their workplaces because of the electronic article surveillance (EAS) systems used in stores to protect merchandise against theft. This study aimed at investigating occupational exposure of cashiers to IF magnetic fields in Finnish stores. Exposure to extremely low frequency (ELF) magnetic fields was also evaluated because cashiers work near various devices operating with 50 Hz electric power. The peak magnetic flux density was measured for IF magnetic fields, and was found to vary from 0.2 to 4 µT at the cashier's seat. ELF magnetic fields from 0.03 to 4.5 µT were found at the cashier's seat. These values are much lower than exposure limits. However, according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) occupational reference levels for IF magnetic fields (141 µT for the peak field) were exceeded in some cases (maximum 189 µT) for short periods of time when cashiers walked through the EAS gates. As the ICNIRP reference levels do not define any minimum time for exposure, additional investigations are recommended to determine compliance with basic restrictions. Even if the basic restrictions are not exceeded, persons working near EAS devices represent an exceptional group of workers with respect to exposure to electromagnetic fields. This group could serve as a basis for epidemiological studies addressing possible health effects of IF magnetic fields. Compliance with the reference levels for IF fields was evaluated using both broadband measurement of peak fields and the ICNIRP summation rule for multiple frequencies. The latter was generally more conservative, and the difference between the two methods was large (>10-fold) for EAS systems using a 58 kHz signal with complex waveform. This indicates that the ICNIRP multiple frequency rule can be unnecessarily conservative when measuring complex waveforms.

  16. Capillary reference half-cell

    DOEpatents

    Hall, Stephen H.

    1996-01-01

    The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods.

  17. Capillary reference half-cell

    DOEpatents

    Hall, S.H.

    1996-02-13

    The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods. 11 figs.

  18. Range Reference Atmosphere, Nellis

    DTIC Science & Technology

    1990-12-01

    mecan to the intercept ol a given probability ellipse, equation 43 is also applicable. 2.7 Statistical Parameters for Non-Standard Orthogonal Axes...clockw ise fronti true north. Rotation of the mecans through (X (legrees: X, Xcos ~(90 -) W + sin (90 - () (44) ’ s (go - o.) u in (90 - (X) (45) Rotation...8217TABLE 3-1. Primary Physical Constants Used in RRA Production. P0 Standard atmospheric pressure at sea level (1.0 13250 X 10 Newton /in 2 ) (2116.22 Ib

  19. REFERENCE RANGE FOR SERUM PARATHYROID HORMONE

    PubMed Central

    Aloia, John F.; Feuerman, Martin; Yeh, James K.

    2006-01-01

    Objective To determine whether the reference range for parathyroid hormone (PTH) should be lowered (from 65 pg/mL to a proposed value of 46 pg/mL) with use of the Allegro radioimmunometric assay. Methods We examined the reference range for PTH, adjusted for serum 25-hydroxyvitamin D (25-OHD), in 503 healthy African American and white women, who were 20 to 80 years old. We also analyzed other factors that are thought to influence PTH levels. Results Univariate predictors of PTH were identified, and a multivariate model was developed with use of the variables and PTH. Serum PTH was significantly higher in black study subjects than in white study subjects (P<0.02). Increasing PTH was also significantly correlated with increasing body mass index, age, and serum creatinine and with decreasing dietary calcium intake and serum 25-OHD levels. A stepwise multiple linear regression analysis yielded the following predictors of PTH: body mass index (R2 = 9.4%), age (R2 = 1.0%), and serum 25-OHD (R2 = 0.8%). In our study population, many PTH values were above the proposed new upper limit of 46 pg/mL. Conclusion The upper limit of the reference range for serum PTH should not be changed. Factors to be considered in analysis of serum PTH values in the upper reference range in patients with normocalcemia include obesity, race, 25-OHD levels, advanced age, serum creatinine, and dietary calcium intake. PMID:16690460

  20. The Prominence of Referring Expressions: Message and Lexical Level Effects

    ERIC Educational Resources Information Center

    Lam, Tuan Q.

    2012-01-01

    In conversation, speakers produce some words with greater intensity, longer duration, and higher fundamental frequency (F0) than other words. By making different words in a sentence more prominent than other words, a speaker can change the meaning implied by a sentence. This thesis explores the relationship between processing in the language…

  1. Uranium recovery from low-level aqueous sources. [76 references

    SciTech Connect

    Kelmers, A.D.; Goeller, H.E.

    1981-03-01

    The aqueous sources of soluble uranium were surveyed and evaluated in terms of the uranium geochemical cycle in an effort to identify potential unexploited resources. Freshwater sources appeared to be too low in uranium content to merit consideration, while seawater, although very dilute (approx. 3.3 ppB), contains approx. 4 x 10/sup 9/ metric tons of uranium in all the world's oceans. A literature review of recent publications and patents concerning uranium recovery from seawater was conducted. Considerable experimental work is currently under way in Japan; less is being done in the European countries. An assessment of the current state of technology is presented in this report. Repeated screening programs have identified hydrous titanium oxide as the most promising candidate absorbent. However, some of its properties such as distribution coefficient, selectivity, loading, and possibly stability appear to render its use inadequate in a practical recovery system. Also, various assessments of the energy efficiency of pumped or tidal power schemes for contacting the sorbent and seawater are in major disagreement. Needed future research and development tasks are discussed. A fundamental sorbent development program to greatly improve sorbent properties would be required to permit practical recovery of uranium from seawater. Major unresolved engineering aspects of such recovery systems are also identified and discussed.

  2. Characterization of the Low Level Waste Reference Glass (LRM)

    SciTech Connect

    Peeler, D.

    1999-05-10

    'The Savannah River Technology Center (SRTC) has participated in a round robin testing program which was conducted under the auspices of the Department of Energy''s (DOE) Tanks Focus Area (TFA) for Immobilization.'

  3. Optical probe with reference fiber

    DOEpatents

    Da Silva, Luiz B.; Chase, Charles L.

    2006-03-14

    A system for characterizing tissue includes the steps of generating an emission signal, generating a reference signal, directing the emission signal to and from the tissue, directing the reference signal in a predetermined manner relative to the emission signal, and using the reference signal to compensate the emission signal. In one embodiment compensation is provided for fluctuations in light delivery to the tip of the probe due to cable motion.

  4. User Preferences in Reference Services: Virtual Reference and Academic Libraries

    ERIC Educational Resources Information Center

    Cummings, Joel; Cummings, Lara; Frederiksen, Linda

    2007-01-01

    This study examines the use of chat in an academic library's user population and where virtual reference services might fit within the spectrum of public services offered by academic libraries. Using questionnaires, this research demonstrates that many within the academic community are open to the idea of chat-based reference or using chat for…

  5. Reach for Reference: Elementary-Middle School Science Reference Collections

    ERIC Educational Resources Information Center

    Safford, Barbara Ripp

    2005-01-01

    This article presents a brief review of some new school science reference works. Two of the sources are traditional, while one is considered experimental. The two traditional reference works reviewed are "The American Heritage Children's Science Dictionary" for upper elementary grades, and "The American Heritage Student Science Dictionary" for…

  6. Reference Readiness for AV Questions.

    ERIC Educational Resources Information Center

    Drolet, Leon L., Jr.

    1981-01-01

    Reviews 50 reference tools which librarians can use to answer almost any audiovisual question including queries on trivia, equipment selection, biographical information, and motion picture ratings. (LLS)

  7. In vitro evaluation of genotoxic effects under magnetic resonant coupling wireless power transfer.

    PubMed

    Mizuno, Kohei; Shinohara, Naoki; Miyakoshi, Junji

    2015-04-07

    Wireless power transfer (WPT) technology using the resonant coupling phenomenon has been widely studied, but there are very few studies concerning the possible relationship between WPT exposure and human health. In this study, we investigated whether exposure to magnetic resonant coupling WPT has genotoxic effects on WI38VA13 subcloned 2RA human fibroblast cells. WPT exposure was performed using a helical coil-based exposure system designed to transfer power with 85.4% efficiency at a 12.5-MHz resonant frequency. The magnetic field at the positions of the cell culture dishes is approximately twice the reference level for occupational exposure as stated in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The specific absorption rate at the positions of the cell culture dishes matches the respective reference levels stated in the ICNIRP guidelines. For assessment of genotoxicity, we studied cell growth, cell cycle distribution, DNA strand breaks using the comet assay, micronucleus formation, and hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene mutation, and did not detect any significant effects between the WPT-exposed cells and control cells. Our results suggest that WPT exposure under the conditions of the ICNIRP guidelines does not cause detectable cellular genotoxicity.

  8. A comparison of foetal SAR in three sets of pregnant female models

    NASA Astrophysics Data System (ADS)

    Dimbylow, Peter J.; Nagaoka, Tomoaki; Xu, X. George

    2009-05-01

    This paper compares the foetal SAR in the HPA hybrid mathematical phantoms with the 26-week foetal model developed at the National Institute of Information and Communications Technology, Tokyo, and the set of 13-, 26- and 38-week boundary representation models produced at Rensselaer Polytechnic Institute. FDTD calculations are performed at a resolution of 2 mm for a plane wave with a vertically aligned electric field incident upon the body from the front, back and two sides from 20 MHz to 3 GHz under isolated conditions. The external electric field values required to produce the ICNIRP public exposure localized restriction of 2 W kg-1 when averaged over 10 g of the foetus are compared with the ICNIRP reference levels.

  9. Assessment of General Public Exposure to LTE signals compared to other Cellular Networks Present in Thessaloniki, Greece.

    PubMed

    Gkonis, Fotios; Boursianis, Achilles; Samaras, Theodoros

    2016-12-15

    To assess general public exposure to electromagnetic fields from Long Term Evolution (LTE) base stations, measurements at 10 sites in Thessaloniki, Greece were performed. Results are compared with other mobile cellular networks currently in use. All exposure values satisfy the guidelines for general public exposure of the International Commission on Non-Ionizing Radiation Protection (ICNIRP), as well as the reference levels by the Greek legislation at all sites. LTE electric field measurements were recorded up to 0.645 V/m. By applying the ICNIRP guidelines, the exposure ratio for all LTE signals is between 2.9 × 10(-5) and 2.8 × 10(-2) From the measurements results it is concluded that the average and maximum power density contribution of LTE downlink signals to the overall cellular networks signals are 7.8% and 36.7%, respectively.

  10. Current level detector

    DOEpatents

    Kerns, Cordon R.

    1977-01-01

    A device is provided for detecting the current level of a DC signal. It includes an even harmonic modulator to which a reference AC signal is applied. The unknown DC signal acts on the reference AC signal so that the output of the modulator includes an even harmonic whose amplitude is proportional to the unknown DC current.

  11. Robot at the Reference Desk?

    ERIC Educational Resources Information Center

    Smith, Karen F.

    1986-01-01

    Describes how a librarian, assisted by a knowledge engineer, developed a computerized reference assistance system for a separate government documents department. Rationale for the expert system, problems in selecting reference materials and user questions to computerize, and the formulation of a workable human/computer interface are covered. A…

  12. Dedicated online virtual reference instruction.

    PubMed

    Guillot, Ladonna; Stahr, Beth; Plaisance, Louise

    2005-01-01

    To facilitate nursing students' information literacy skills and enhance traditional library user services, academic librarians have developed synchronous (real-time) online virtual reference instruction in nursing research classes. The authors discuss collaborative efforts of nursing and library faculty in planning, implementing, and evaluating a discipline-specific virtual reference pilot program.

  13. Moving Reference to the Web.

    ERIC Educational Resources Information Center

    McGlamery, Susan; Coffman, Steve

    2000-01-01

    Explores the possibility of using Web contact center software to offer reference assistance to remote users. Discusses a project by the Metropolitan Cooperative Library System/Santiago Library System consortium to test contact center software and to develop a virtual reference network. (Author/LRW)

  14. The Virtual Reference Librarian's Handbook.

    ERIC Educational Resources Information Center

    Lipow, Anne Grodzins

    This book is a practical guide to librarians and their administrators who are thinking about or in the early stages of providing virtual reference service. Part 1, "The Decision to Go Virtual," provides a context for thinking about virtual reference, including the benefits and problems, getting in the virtual frame of mind, and shopping…

  15. Ethics and the Reference Librarian.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    1999-01-01

    Discussion of ethical reference practice focuses on guidelines for the individual reference librarian's interactions with clients. Topics include the professional-client relationship; competence; diligence; confidentiality; independence of judgment; honesty and candor; and obligations to third parties, including the democratic society at large.…

  16. Reference for radiographic film interpreters

    NASA Technical Reports Server (NTRS)

    Austin, D. L.

    1970-01-01

    Reference of X-ray film images provides examples of weld defects, film quality, stainless steel welded tubing, and acceptable weld conditions. A summary sheet details the discrepancies shown on the film strip. This reference aids in interpreting and evaluating radiographic film of weldments.

  17. Expert Systems for Reference Work.

    ERIC Educational Resources Information Center

    Parrot, James R.

    1986-01-01

    Discussion of library reference work that may be suitable for use of expert systems focuses on (1) information and literature searches, and (2) requests to interpret bibliographic references and locate items listed. Systems and computer-assisted instruction modules designed for information retrieval at the University of Waterloo Library are…

  18. Technostress and the Reference Librarian.

    ERIC Educational Resources Information Center

    Kupersmith, John

    1992-01-01

    Defines "technostress" as the stress experienced by reference librarians who must constantly deal with the demands of new information technology and the changes they produce in the work place. Discussion includes suggested ways in which both organizations and individuals can work to reduce stress. (27 references) (LAE)

  19. Changing Roles for References Librarians.

    ERIC Educational Resources Information Center

    Kelly, Julia; Robbins, Kathryn

    1996-01-01

    Discusses the future outlook for reference librarians, with topics including: "Technology as the Source of Change"; "Impact of the Internet"; "Defining the Virtual Library"; "Rethinking Reference"; "Out of the Library and into the Streets"; "Asking Users About Their Needs"; "Standardization and Artificial Intelligence"; "The Financial Future"; and…

  20. Queuing Theory and Reference Transactions.

    ERIC Educational Resources Information Center

    Terbille, Charles

    1995-01-01

    Examines the implications of applying the queuing theory to three different reference situations: (1) random patron arrivals; (2) random durations of transactions; and (3) use of two librarians. Tables and figures represent results from spreadsheet calculations of queues for each reference situation. (JMV)

  1. Improved ultrasonic standard reference blocks

    NASA Technical Reports Server (NTRS)

    Eitzen, D. G.; Sushinsky, G. F.; Chwirut, D. J.; Bechtoldt, C. J.; Ruff, A. W.

    1976-01-01

    A program to improve the quality, reproducibility and reliability of nondestructive testing through the development of improved ASTM-type ultrasonic reference standards is described. Reference blocks of aluminum, steel, and titanium alloys are to be considered. Equipment representing the state-of-the-art in laboratory and field ultrasonic equipment was obtained and evaluated. RF and spectral data on ten sets of ultrasonic reference blocks have been taken as part of a task to quantify the variability in response from nominally identical blocks. Techniques for residual stress, preferred orientation, and micro-structural measurements were refined and are applied to a reference block rejected by the manufacturer during fabrication in order to evaluate the effect of metallurgical condition on block response. New fabrication techniques for reference blocks are discussed and ASTM activities are summarized.

  2. Requirements for Reference (Calibration) Laboratories in Laboratory Medicine

    PubMed Central

    Siekmann, Lothar

    2007-01-01

    In addition to reference measurement procedures and reference materials, reference or calibration laboratories play an integral role in the implementation of measurement traceability in routine laboratories. They provide results of measurements using higher-order methods, e.g. isotope dilution mass spectrometry and may assign values to materials to be used for external quality assessment programs and to secondary reference materials. The requirements for listing of laboratories that provide reference measurement services include a statement of the metrological level or principle of measurement, accreditation as a calibration laboratory according to ISO 15195 and the participation in a proficiency testing system (regular inter-laboratory comparisons) for reference laboratories. Ring trials are currently conducted for thirty well-defined measurands and the results are made available to all laboratories. Through the use of reference laboratory services that are listed by the Joint Committee for Traceability in Laboratory Medicine there is the opportunity to further promote traceability and standardisation of laboratory measurements. PMID:18392129

  3. The International Geomagnetic Reference Field, 2005

    USGS Publications Warehouse

    Rukstales, Kenneth S.; Love, Jeffrey J.

    2007-01-01

    This is a set of five world charts showing the declination, inclination, horizontal intensity, vertical component, and total intensity of the Earth's magnetic field at mean sea level at the beginning of 2005. The charts are based on the International Geomagnetic Reference Field (IGRF) main model for 2005 and secular change model for 2005-2010. The IGRF is referenced to the World Geodetic System 1984 ellipsoid. Additional information about the USGS geomagnetism program is available at: http://geomag.usgs.gov/

  4. Review of the Reference Dose and Reference Concentration Processes Document

    EPA Pesticide Factsheets

    Summarizes the review and deliberations of the Risk Assessment Forum’s RfD/RfC Technical Panel and its recommendations for improvements in oral referencedose/inhalation reference concentration (RfD/RfC) process.

  5. Level sensing system

    SciTech Connect

    Custer, C.S.

    1989-01-10

    A system is described for sensing the level of a body of liquid in a container, the system comprising: (a) a shaft secured parallel to a vertical axis of the container, the shaft having therein a plurality of magnetic position responsive switches; (b) a reference elemental situated circumferentially about the shaft and secured at a fixed level thereto, the reference element having a magnetic axis co-directional with the axis of the shaft; and (c) a measuring and sensing element situated circumferentially about the shaft and vertically above the reference element but without securement thereto, the measuring element having a magnetic axis co-directional with the axis of the reference element, the axis having a polarity in repulsive relationship to the magnetic axis of the reference element, the sensing element having a negative buoyancy relative to the specific gravity of the liquid within the container.

  6. Reference and Standard Atmosphere Models

    NASA Technical Reports Server (NTRS)

    Johnson, Dale L.; Roberts, Barry C.; Vaughan, William W.; Parker, Nelson C. (Technical Monitor)

    2002-01-01

    This paper describes the development of standard and reference atmosphere models along with the history of their origin and use since the mid 19th century. The first "Standard Atmospheres" were established by international agreement in the 1920's. Later some countries, notably the United States, also developed and published "Standard Atmospheres". The term "Reference Atmospheres" is used to identify atmosphere models for specific geographical locations. Range Reference Atmosphere Models developed first during the 1960's are examples of these descriptions of the atmosphere. This paper discusses the various models, scopes, applications and limitations relative to use in aerospace industry activities.

  7. Africa South of the Sahara: A Guide to Reference Sources.

    ERIC Educational Resources Information Center

    Mason, Mary, Comp.

    This annotated bibliography has been compiled as an introduction to reference resources for college-level African studies and to suggest useful tools for literature searches. It is a guide to materials in the library of McGill University. Call numbers are included. The titles cited refer to Africa South of the Sahara as a whole or to large…

  8. Sports Reference: A Core Collection.

    ERIC Educational Resources Information Center

    Safford, Barbara Ripp

    2003-01-01

    Discusses reasons for including sports books in school library reference collections, explains why they should not be found only in public library collections, and provides six annotated bibliographies of sports books suitable for intermediate or middle school library collections. (LRW)

  9. Computerizing the Reference Desk Schedule.

    ERIC Educational Resources Information Center

    deHaas, Pat

    1983-01-01

    Discussion of the scheduling procedures of librarians' hours at the reference desk at the Rutherford Humanities and Social Sciences Library, University of Alberta, highlights services provided, the preference table system, and manual scheduling versus computer scheduling. (EJS)

  10. Genetics Home Reference: Laron syndrome

    MedlinePlus

    ... AL. Obesity, diabetes and cancer: insight into the relationship from a cohort with growth hormone receptor deficiency. ... healthcare professional . About Genetics Home Reference Site Map Customer Support Selection Criteria for Links USA.gov Copyright ...

  11. Genetics Home Reference: Miyoshi myopathy

    MedlinePlus

    ... Itoyama Y. Dysferlin mutations in Japanese Miyoshi myopathy: relationship to phenotype. Neurology. 2003 Jun 10;60(11): ... healthcare professional . About Genetics Home Reference Site Map Customer Support Selection Criteria for Links USA.gov Copyright ...

  12. Genetics Home Reference: Asperger syndrome

    MedlinePlus

    ... a combination of genetic variations and environmental factors influence the development of this complex condition. Asperger syndrome ... healthcare professional . About Genetics Home Reference Site Map Customer Support Selection Criteria for Links USA.gov Copyright ...

  13. Selected Reference Books of 1999.

    ERIC Educational Resources Information Center

    McIlvaine, Eileen

    2000-01-01

    Presents annotated bibliographies of a selection of recent scholarly and general reference works under the subject headings of publishing, periodical indexes, philosophy and religion, literature, music, art, photography, social sciences, business, history, and new editions. (LRW)

  14. Genetics Home Reference: WAGR syndrome

    MedlinePlus

    ... signs and symptoms of WAGR syndrome can include childhood-onset obesity, inflammation of the pancreas (pancreatitis), and kidney failure. When WAGR syndrome includes childhood-onset obesity, it is often referred to as WAGRO syndrome. ...

  15. Improved ultrasonic standard reference blocks

    NASA Technical Reports Server (NTRS)

    Eitzen, D. G.

    1975-01-01

    A program to improve the quality, reproducibility and reliability of nondestructive testing through the development of improved ASTM-type ultrasonic reference standards is described. Reference blocks of aluminum, steel, and titanium alloys were considered. Equipment representing the state-of-the-art in laboratory and field ultrasonic equipment was obtained and evaluated. Some RF and spectral data on ten sets of ultrasonic reference blocks were taken as part of a task to quantify the variability in response from nominally identical blocks. Techniques for residual stress, preferred orientation, and microstructural measurements were refined and are applied to a reference block rejected by the manufacturer during fabrication in order to evaluate the effect of metallurgical condition on block response.

  16. Virtual reference: chat with us!

    PubMed

    Lapidus, Mariana; Bond, Irena

    2009-01-01

    Virtual chat services represent an exciting way to provide patrons of medical libraries with instant reference help in an academic environment. The purpose of this article is to examine the implementation, marketing process, use, and development of a virtual reference service initiated at the Massachusetts College of Pharmacy and Health Sciences and its three-campus libraries. In addition, this paper will discuss practical recommendations for the future improvement of the service.

  17. Space Station reference configuration description

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The data generated by the Space Station Program Skunk Works over a period of 4 months which supports the definition of a Space Station reference configuration is documented. The data were generated to meet these objectives: (1) provide a focal point for the definition and assessment of program requirements; (2) establish a basis for estimating program cost; and (3) define a reference configuration in sufficient detail to allow its inclusion in the definition phase Request for Proposal (RFP).

  18. WILDLIFE TOXICITY REFERENCE VALUES FOR POLYNUCLEAR AROMATIC HYDROCARBONS AND DDT

    EPA Science Inventory

    The presentation will provide an overview of the procedures used in deriving mammalian and avian wildlife toxicity reference values to be used in development of ecological soil screening levels (Eco-SSLs).

  19. Virtual Reference Interferometry: Theory & Experiment

    NASA Astrophysics Data System (ADS)

    Galle, Michael Anthony

    This thesis introduces the idea that a simulated interferogram can be used as a reference for an interferometer. This new concept represents a paradigm shift from the conventional thinking, where a reference is the phase of a wavefront that traverses a known path. The simulated interferogram used as a reference is called a virtual reference. This thesis develops the theory of virtual reference interferometry and uses it for the characterization of chromatic dispersion in short length (<1m) fibers and optical components. Characterization of chromatic dispersion on short length fiber and optical components is a very difficult challenge. Accurate measurement of first and second order dispersion is important for applications from optical component design to nonlinear photonics, sensing and communications. Techniques for short-length dispersion characterization are therefore critical to the development of many photonic systems. The current generation of short-length dispersion measurement techniques are either easy to operate but lack sufficient accuracy, or have sufficient accuracy but are difficult to operate. The use of a virtual reference combines the advantages of these techniques so that it is both accurate and easy to operate. Chromatic dispersion measurements based on virtual reference interferometry have similar accuracy as the best conventional measurement techniques due to the ability to measure first and second order dispersion directly from the interference pattern. Unique capabilities of virtual reference interferometry are demonstrated, followed by a derivation of the operational constraints and system parameters. The technique is also applied to the characterization of few-mode fibers, a hot topic in telecommunications research where mode division multiplexing promises to expand network bandwidth. Also introduced is the theory of dispersive virtual reference interferometry, which can be used to overcome the bandwidth limitations associated with the

  20. Using Virtual Reference Transcripts for Staff Training.

    ERIC Educational Resources Information Center

    Ward, David

    2003-01-01

    Describes a method of library staff training based on chat transcript analysis in which graduate student workers at a university reference desk examined transcripts of actual virtual reference desk transactions to analyze reference interviews. Discusses reference interview standards, reference desk behavior, and reference interview skills in…

  1. Sequence Factorization with Multiple References

    PubMed Central

    Wandelt, Sebastian; Leser, Ulf

    2015-01-01

    The success of high-throughput sequencing has lead to an increasing number of projects which sequence large populations of a species. Storage and analysis of sequence data is a key challenge in these projects, because of the sheer size of the datasets. Compression is one simple technology to deal with this challenge. Referential factorization and compression schemes, which store only the differences between input sequence and a reference sequence, gained lots of interest in this field. Highly-similar sequences, e.g., Human genomes, can be compressed with a compression ratio of 1,000:1 and more, up to two orders of magnitude better than with standard compression techniques. Recently, it was shown that the compression against multiple references from the same species can boost the compression ratio up to 4,000:1. However, a detailed analysis of using multiple references is lacking, e.g., for main memory consumption and optimality. In this paper, we describe one key technique for the referential compression against multiple references: The factorization of sequences. Based on the notion of an optimal factorization, we propose optimization heuristics and identify parameter settings which greatly influence 1) the size of the factorization, 2) the time for factorization, and 3) the required amount of main memory. We evaluate a total of 30 setups with a varying number of references on data from three different species. Our results show a wide range of factorization sizes (optimal to an overhead of up to 300%), factorization speed (0.01 MB/s to more than 600 MB/s), and main memory usage (few dozen MB to dozens of GB). Based on our evaluation, we identify the best configurations for common use cases. Our evaluation shows that multi-reference factorization is much better than single-reference factorization. PMID:26422374

  2. Reference group effects in the measurement of personality and attitudes.

    PubMed

    Credé, Marcus; Bashshur, Michael; Niehorster, Sarah

    2010-09-01

    Reference-group effects (discovered in cross-cultural settings) occur when responses to self-report items are based not on respondents' absolute level of a construct but rather on their level relative to a salient comparison group. In this article, we examine the impact of reference-group effects on the assessment of self-reported personality and attitudes. Two studies illustrate that a reference-group effect can be induced by small changes to instruction sets, changes that mirror the instruction sets of commonly used measures of personality. Scales that specified different reference groups showed substantial reductions in criterion-related validities for academic performance, self-reported counterproductive behaviors, and self-reported health outcomes relative to reference-group-free versions of those scales.

  3. Multi-reference vibration correlation methods

    SciTech Connect

    Pfeiffer, Florian; Rauhut, Guntram

    2014-02-14

    State-specific vibration correlation methods beyond the vibrational multi-configuration self-consistent field (VMCSCF) approximation have been developed, which allow for the accurate calculation of state energies for systems suffering from strong anharmonic resonances. Both variational multi-reference configuration interaction approaches and an implementation of approximate 2nd order vibrational multi-reference perturbation theory are presented. The variational approach can be significantly accelerated by a configuration selection scheme, which leads to negligible deviations in the final results. Relaxation effects due to the partitioning of the correlation space and the performance of a VMCSCF modal basis in contrast to a standard modal basis obtained from vibrational self-consistent field theory have been investigated in detail. Benchmark calculations based on high-level potentials are provided for the propargyl cation and cis-diazene.

  4. A Closer Look at the Thresholds of Thermal Damage: Workshop Report by an ICNIRP Task Group

    PubMed Central

    Sienkiewicz, Zenon; van Rongen, Eric; Croft, Rodney; Ziegelberger, Gunde; Veyret, Bernard

    2016-01-01

    Abstract The International Commission on Non-Ionizing Radiation Protection issued guidelines in 1998 for limiting public and occupational exposure to radiofrequency electromagnetic fields (100 kHz to 300 GHz). As part of the process of updating this advice, a 2‐d workshop titled “A closer look at the thresholds of thermal damage” was held from 26–28 May 2015 in Istanbul to re-examine the thermal basis of the guidelines and to provide further information on heat-related effects and thresholds of thermal damage. Overall, the workshop provided much useful information relevant to revision of the guidelines. Participants indicated that the effects of heating from radiofrequency fields are consistent with those from other sources, and that the information derived from those studies can be applied to radiofrequency-induced heating. Another conclusion was that absolute temperature of tissues was more important for thermal damage than temperature change. The discussion suggested that the 6‐min averaging time used in international guidelines was valid for whole-body exposures but with a large uncertainty: 30 min may be a more appropriate averaging time for localized exposures, and less than 1 min for implanted medical devices. The duration of whole-body radiofrequency exposure is a critical parameter that often determines the effect threshold, but this will be affected by other, ongoing thermoregulation, which is dependant on many factors. The thresholds for localized radiofrequency exposure were difficult to determine because of the potential range of exposure conditions and the possibility of radiofrequency-induced local hotspots. Suggestions for future dose metrics and further research were discussed and are included in this report. PMID:27472755

  5. Virtual Reference, Real Money: Modeling Costs in Virtual Reference Services

    ERIC Educational Resources Information Center

    Eakin, Lori; Pomerantz, Jeffrey

    2009-01-01

    Libraries nationwide are in yet another phase of belt tightening. Without an understanding of the economic factors that influence library operations, however, controlling costs and performing cost-benefit analyses on services is difficult. This paper describes a project to develop a cost model for collaborative virtual reference services. This…

  6. Reference Anytime Anywhere: Towards Virtual Reference Services at Penn State.

    ERIC Educational Resources Information Center

    Moyo, Lesley M.

    2002-01-01

    Outlines the service rationale, software and technology considerations taken by the Pennsylvania State University library in planning towards online, real-time reference services and provides an overview of the planned pilot project. Discusses recent trends in academic electronic libraries, including providing value-added services to support…

  7. Reference Anywhere, Anytime: Recent Works on Virtual Reference

    ERIC Educational Resources Information Center

    Lindsay, Elizabeth Blakesley

    2008-01-01

    The topic of virtual reference has been a popular one in the past year, and this column highlights a range of those articles. Included are overviews of the topic, articles addressing specific technological solutions and concerns, and pieces that explore the intricacies of delivering and assessing a "traditional" service through a…

  8. The Virtual Reference Librarian: Using Desktop Videoconferencing for Distance Reference.

    ERIC Educational Resources Information Center

    Pagell, Ruth A.

    1996-01-01

    The Center for Business Information and the Goizueta Business School at Emory University (Georgia) tested desktop videoconferencing as a means to deliver reference services, including consultation, documentation, training, and sharing of CD-ROM databases. Provides a brief overview of the technology, describes project beta testing, and discusses…

  9. Reference and Reference Failures. Technical Report No. 398.

    ERIC Educational Resources Information Center

    Goodman, Bradley A.

    In order to build robust natural language processing systems that can detect and recover from miscommunication, the investigation of how people communicate and how they recover from problems in communication described in this artificial intelligence report focused on reference problems which a listener may have in determining what or whom a…

  10. Reference-based phasing using the Haplotype Reference Consortium panel.

    PubMed

    Loh, Po-Ru; Danecek, Petr; Palamara, Pier Francesco; Fuchsberger, Christian; A Reshef, Yakir; K Finucane, Hilary; Schoenherr, Sebastian; Forer, Lukas; McCarthy, Shane; Abecasis, Goncalo R; Durbin, Richard; L Price, Alkes

    2016-11-01

    Haplotype phasing is a fundamental problem in medical and population genetics. Phasing is generally performed via statistical phasing in a genotyped cohort, an approach that can yield high accuracy in very large cohorts but attains lower accuracy in smaller cohorts. Here we instead explore the paradigm of reference-based phasing. We introduce a new phasing algorithm, Eagle2, that attains high accuracy across a broad range of cohort sizes by efficiently leveraging information from large external reference panels (such as the Haplotype Reference Consortium; HRC) using a new data structure based on the positional Burrows-Wheeler transform. We demonstrate that Eagle2 attains a ∼20× speedup and ∼10% increase in accuracy compared to reference-based phasing using SHAPEIT2. On European-ancestry samples, Eagle2 with the HRC panel achieves >2× the accuracy of 1000 Genomes-based phasing. Eagle2 is open source and freely available for HRC-based phasing via the Sanger Imputation Service and the Michigan Imputation Server.

  11. Fetal exposure to low frequency electric and magnetic fields

    NASA Astrophysics Data System (ADS)

    Cech, R.; Leitgeb, N.; Pediaditis, M.

    2007-02-01

    To investigate the interaction of low frequency electric and magnetic fields with pregnant women and in particular with the fetus, an anatomical voxel model of an 89 kg woman at week 30 of pregnancy was developed. Intracorporal electric current density distributions due to exposure to homogeneous 50 Hz electric and magnetic fields were calculated and results were compared with basic restrictions recommended by ICNIRP guidelines. It could be shown that the basic restriction is met within the central nervous system (CNS) of the mother at exposure to reference level of either electric or magnetic fields. However, within the fetus the basic restriction is considerably exceeded. Revision of reference levels might be necessary.

  12. PIRLA DBMS quick reference guide

    SciTech Connect

    Smith, J.

    1991-11-01

    The handbook facilitates the use of the PIRLA (Paleoecological Investigation of Recent Lake Acidification) database retrievals by showing all possible inputs, outputs, ranges, and quick reference information that you would want at your fingertips when accessing the PIRLA data. The handbook assumes no prior knowledge of PIRLA or SIR (a database management system), although a basic familiarity with computers is helpful. The PIRLA Data Base Management System User's Manual is recommended for reference, much additional detail, description of the intrinsic structure of the PIRLA database, and how it is set up under SIR.

  13. Reference handbook: Diesel engines and governors

    SciTech Connect

    Not Available

    1991-01-18

    The purpose of this handbook is to provide Rocky Flats personnel with the information necessary to understand diesel engines and governors. Upon completion of this handbook you should be able to do the following tasks: Explain the two major differences between diesel and gasoline engines. Identify 12 major diesel engine components. Explain the function of pistons. Explain the functions of crankshafts and blowers. Define the following terms: Cylinder Block Crown End Skirt End Bosses Babbitt Compression Ignition Cycle Governor Speed Controller Fuel Injector. Describe how the crankshaft is related to the camshaft. Identify the purpose of a flywheel. Identify the four phases of the combustion cycle. Compare and contrast two-cycle and four-cycle engines. Explain the difference between a filter and a strainer. Scope: This handbook is designed for use by experienced Rocky Flats operators to reinforce and improve their current knowledge level, and by entry-level operators to ensure that they possess a minimum level of fundamental knowledge. Diesel Engines and Governors is applicable to many job classifications and can be used as a reference for classroom work or for self-study. Although this reference handbook is by no means all-encompassing, you will gain enough information about this subject area to assist you in contributing to the safe operation of Rocky Flats Plant.

  14. Specific absorption rate and electric field measurements in the near field of six mobile phone base station antennas.

    PubMed

    Toivonen, Tommi; Toivo, Tim; Puranen, Lauri; Jokela, Kari

    2009-05-01

    In this article, the exposure to radio frequency electromagnetic fields was studied in close proximity (distances of 10, 100, 300, and 600 mm) to six base station antennas. The specific absorption rate (SAR) in 800 mm x 500 mm x 200 mm box phantom as well as unperturbed electric field (E) in air was measured. The results were used to determine whether the measurement of local maximum of unperturbed electric field can be used as a compliance check for local exposure. Also, the conservativeness of this assessment method compared to the ICNIRP basic restriction was studied. Moreover, the assessment of whole-body exposure was discussed and the distance ranges presented in which the ICNIRP limit for local exposure could be exceeded before the limit for whole-body SAR. These results show that the electric field measurement alone can be used for easy compliance check for the local exposure at all distances and for all antenna types studied. However, in some cases when the local peak value of E was compared directly to the ICNIRP reference level for unperturbed E, the exposure was overestimated only very slightly (by factor 1.1) compared to the basic restriction for localized SAR in a human, and hence these results can not be generalized to all antenna types. Moreover, it was shown that the limit for localized exposure could be exceeded before the limit for the whole-body average SAR, if the distance to the antenna was less than 240 mm.

  15. Tractor Transmissions. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Agricultural Engineering and Vocational Agriculture, Athens, GA.

    The manual was developed as a reference for teaching students about transmissions in farm tractors. The manual is divided into five sections: (1) transmission history, (2) gears and bearings in transmission, (3) sliding-gear transmissions, (4) planetary gearing, and (5) glossary. The working principles of the sliding-gear transmission, the most…

  16. When Is Cataphoric Reference Recognised?

    ERIC Educational Resources Information Center

    Filik, Ruth; Sanford, Anthony J.

    2008-01-01

    Pronouns typically have explicit antecedents in the prior discourse otherwise processing difficulty is experienced. However, it has been argued [Gordon, P. C., & Hendrick, R. (1997). "Intuitive knowledge of linguistic co-reference." "Cognition, 62", 325-370; Gordon, P. C., & Hendrick, R. (1998). "The representation and processing of co-reference…

  17. The Rosia Language Reference Manual

    DTIC Science & Technology

    1981-12-01

    Alternate database 16 Anaphora 26, 30, 56 Anaphoric reference 30 Arithmetic expressions 33 Arithmetic operators 8 Bind 54 Binding 54, 57 BNF 94...Descriptions as Class Membership Tests .......... 28 4.2.7. Descriptions and Modification ................... 29 4.2.8. Anaphoric Descriptions...54 4.9.3. Variable Binding ................................ 54 4.9.4. Pattern Matching ................................ 55 5

  18. Newfoundland. Reference Series No. 34.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Newfoundland and is suitable for teacher reference or student reading. Separate sections discuss geography and climate, history, economy, population and settlement, arts and culture, leisure and recreation, and heritage. Specific topics include the…

  19. Selected Reference Books of 1998.

    ERIC Educational Resources Information Center

    McIlvaine, Eileen

    1999-01-01

    Reviews a selection of recent scholarly and general reference works under the categories of Periodicals and Newspapers, Philosophy, Literature, Film and Radio, Art and Architecture, Music, Political Science, Women's Studies, and History. A brief summary of new editions of standard works is provided at the end of the articles. (AEF)

  20. Quebec. Reference Series No. 30.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Quebec and is suitable for teacher reference or student reading. Separate sections discuss geography, climate, population, history, political history, recent politics, agriculture, forestry, mining, manufacturing and industry, hydroelectric power,…

  1. [Developmental Placement.] Collected Research References.

    ERIC Educational Resources Information Center

    Bjorklund, Gail

    Drawing on information and references in the ERIC system, this literature review describes research related to a child's developmental placement. The issues examined include school entrance age; predictive validity, reliability, and features of Gesell School Readiness Assessment; retention; and the effectiveness of developmental placement. A…

  2. Manitoba. Reference Series No. 28.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Manitoba and is suitable for teacher reference or student reading. Separate sections discuss agriculture, mining, energy, transportation and communication, fishing, forestry, fur trapping, health and social services, education, and political life. Specific…

  3. Ontario. Reference Series No. 29.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Ontario and is suitable for teacher reference or student reading. Separate sections discuss geography, climate, history, agriculture, forestry, fishing, mining, manufacturing, transportation, energy, arts and culture, sports and recreation, and people and…

  4. Chapter 11: Dietary reference intakes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Dietary Reference Intakes (DRI) are a set of recommendations intended to provide guidance in evaluating nutrient intakes and planning meals on the basis of nutrient adequacy. In contrast to their predecessor, Recommended Dietary Allowances last published in 1989, the DRIs differ in two ways: th...

  5. A REFERENCE GRAMMAR OF BENGALI.

    ERIC Educational Resources Information Center

    RAY, PUNYA SLOKA; AND OTHERS

    A REFERENCE GRAMMAR WAS PRODUCED FOR THE BENGALI LANGUAGE. THE WORK CONTAINS CHAPTERS ON--(1) SOCIAL AND HISTORICAL BACKGROUND, (2) HISTORY OF THE LANGUAGE, (3) SOURCES OF LEXICAL ITEMS, (4) ORTHOGRAPHY, (5) PHONOLOGY, (6) NOUN INFLECTIONS, (7) VERBS, (8) POSTPOSITIONS, (9) ENCLITICS, (10) NUMERALS, (11) NEGATION, (12) FORMATIVE AFFIXES IN…

  6. Saskatchewan. Reference Series No. 27.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Saskatchewan and is suitable for teacher reference or student reading. Separate sections discuss history, economy, oil, uranium, potash, coal, minerals and metals, agriculture, forestry, tourism and recreation, arts and culture, and people. Specific topics…

  7. Reference Works in Reduced Size

    ERIC Educational Resources Information Center

    Hennessey, David

    1977-01-01

    Lower cost and less shelf space requirements have made major reference works in miniaturized print editions attractive to small libraries. The major disadvantage is the necessity of a magnifying glass for reading entries. A bibliography of reduced-size editions is included. (JAB)

  8. A Reference Grammar of Kashmiri.

    ERIC Educational Resources Information Center

    Kachru, Braj B.

    This study was developed for two pedagogical purposes--first, to provide a skeleton grammar of the Kashmiri language which could be used by teachers of Kashmiri to develop teaching materials for both Indian and non-Indian learners of Kashmiri; and second, to provide an introductory reference manual of Kashmiri for students of the language. The…

  9. Childhood Obesity. Special Reference Briefs.

    ERIC Educational Resources Information Center

    Winick, Myron

    This reference brief deals with the problem of childhood obesity and how it can lead to obesity in the adult. Eighty-four abstracts are presented of studies on the identification, prevention, and treatment of obesity in children, focusing on diet and psychological attitudes. Subjects of the studies were children ranging in age from infancy through…

  10. Guam and Micronesia Reference Sources.

    ERIC Educational Resources Information Center

    Goetzfridt, Nicholas J.; Goniwiecha, Mark C.

    1993-01-01

    This article lists reference sources for studying Guam and Micronesia. The entries are arranged alphabetically by main entry within each section in the categories of: (1) bibliographical works; (2) travel and guide books; (3) handbooks and surveys; (4) dictionaries; (5) yearbooks; (6) periodical and newspaper publications; and (7) audiovisual…

  11. Human Rights: The Essential Reference.

    ERIC Educational Resources Information Center

    Devine, Carol; Hansen, Carol Rae; Wilde, Ralph; Bronkhorst, Daan; Moritz, Frederic A.; Rolle, Baptiste; Sherman, Rebecca; Southard, Jo Lynn; Wilkinson, Robert; Poole, Hilary, Ed.

    This reference work documents the history of human rights theory, explains each article of the Universal Declaration of Human Rights, explores the contemporary human rights movement, and examines the major human rights issues facing the world today. This book is the first to combine historical and contemporary perspectives on these critical…

  12. Alberta. Reference Series No. 26.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Alberta and is suitable for teacher reference or student reading. Separate sections discuss the history and population, the provincial government, the economy, transportation, communications, mineral resources, agriculture, manufacturing, forest products,…

  13. Mobile Technologies and Roving Reference

    ERIC Educational Resources Information Center

    Penner, Katherine

    2011-01-01

    As 21st century librarians, we have made apt adjustments for reaching out into the digital world, but we need to consider the students who still use library services within our walls. We can use available handheld, mobile technologies to help patrons too shy to approach the desk and free library staff to bring reference service directly to patrons.

  14. Expert Systems in Reference Services.

    ERIC Educational Resources Information Center

    Roysdon, Christine, Ed.; White, Howard D., Ed.

    1989-01-01

    Eleven articles introduce expert systems applications in library and information science, and present design and implementation issues of system development for reference services. Topics covered include knowledge based systems, prototype development, the use of artificial intelligence to remedy current system inadequacies, and an expert system to…

  15. Selected Reference Books of 1992.

    ERIC Educational Resources Information Center

    McIlvaine, Eileen

    1993-01-01

    Presents an annotated bibliography of 40 recent scholarly and general works of interest to reference workers in university libraries. Topics areas covered include philosophy, religion, language, literature, architecture, economics, law, area studies, Russia and the Soviet Union, women's studies, and Christopher Columbus. New editions and…

  16. Levels at gaging stations

    USGS Publications Warehouse

    Kenney, Terry A.

    2010-01-01

    Operational procedures at U.S. Geological Survey gaging stations include periodic leveling checks to ensure that gages are accurately set to the established gage datum. Differential leveling techniques are used to determine elevations for reference marks, reference points, all gages, and the water surface. The techniques presented in this manual provide guidance on instruments and methods that ensure gaging-station levels are run to both a high precision and accuracy. Levels are run at gaging stations whenever differences in gage readings are unresolved, stations may have been damaged, or according to a pre-determined frequency. Engineer's levels, both optical levels and electronic digital levels, are commonly used for gaging-station levels. Collimation tests should be run at least once a week for any week that levels are run, and the absolute value of the collimation error cannot exceed 0.003 foot/100 feet (ft). An acceptable set of gaging-station levels consists of a minimum of two foresights, each from a different instrument height, taken on at least two independent reference marks, all reference points, all gages, and the water surface. The initial instrument height is determined from another independent reference mark, known as the origin, or base reference mark. The absolute value of the closure error of a leveling circuit must be less than or equal to ft, where n is the total number of instrument setups, and may not exceed |0.015| ft regardless of the number of instrument setups. Closure error for a leveling circuit is distributed by instrument setup and adjusted elevations are determined. Side shots in a level circuit are assessed by examining the differences between the adjusted first and second elevations for each objective point in the circuit. The absolute value of these differences must be less than or equal to 0.005 ft. Final elevations for objective points are determined by averaging the valid adjusted first and second elevations. If final elevations

  17. Locating and parsing bibliographic references in HTML medical articles.

    PubMed

    Zou, Jie; Le, Daniel; Thoma, George R

    2010-06-01

    The set of references that typically appear toward the end of journal articles is sometimes, though not always, a field in bibliographic (citation) databases. But even if references do not constitute such a field, they can be useful as a preprocessing step in the automated extraction of other bibliographic data from articles, as well as in computer-assisted indexing of articles. Automation in data extraction and indexing to minimize human labor is key to the affordable creation and maintenance of large bibliographic databases. Extracting the components of references, such as author names, article title, journal name, publication date and other entities, is therefore a valuable and sometimes necessary task. This paper describes a two-step process using statistical machine learning algorithms, to first locate the references in HTML medical articles and then to parse them. Reference locating identifies the reference section in an article and then decomposes it into individual references. We formulate this step as a two-class classification problem based on text and geometric features. An evaluation conducted on 500 articles drawn from 100 medical journals achieves near-perfect precision and recall rates for locating references. Reference parsing identifies the components of each reference. For this second step, we implement and compare two algorithms. One relies on sequence statistics and trains a Conditional Random Field. The other focuses on local feature statistics and trains a Support Vector Machine to classify each individual word, followed by a search algorithm that systematically corrects low confidence labels if the label sequence violates a set of predefined rules. The overall performance of these two reference-parsing algorithms is about the same: above 99% accuracy at the word level, and over 97% accuracy at the chunk level.

  18. Circuit and method for producing a flexible reference voltage

    NASA Technical Reports Server (NTRS)

    Thornton, Roger D. (Inventor)

    1993-01-01

    A flexible reference voltage circuit includes a circuit for producing a first digital signal representative of a range of reference voltage levels; a circuit for producing a second digital signal representative of a selected reference voltage level within the range of reference voltage levels; an adder for adding the first and second digital signals to produce a third digital signal; and a digital to analog converter for providing an output voltage in response to the third digital signal. The method of producing a flexible reference voltage performed by the circuit is also claimed. The invention can be used with a differential protection circuit to provide a series of trip level ranges, with a series of selectable trip levels in each range. This is accomplished in a high accuracy circuit which is relatively simple to construct, thereby minimizing size and complexity of the current sensor module, in differential protection applications, or the circuitry, if used in a power system controller. Standard digital logic components can be used to perform the necessary range/level decoding.

  19. Thermocouple, multiple junction reference oven

    NASA Technical Reports Server (NTRS)

    Leblanc, L. P. (Inventor)

    1981-01-01

    An improved oven for maintaining the junctions of a plurality of reference thermocouples at a common and constant temperature is described. The oven is characterized by a cylindrical body defining a heat sink with axially extended-cylindrical cavity a singularized heating element which comprises a unitary cylindrical heating element consisting of a resistance heating coil wound about the surface of metallic spool with an axial bore defined and seated in the cavity. Other features of the oven include an annular array of radially extended bores defined in the cylindrical body and a plurality of reference thermocouple junctions seated in the bores in uniformly spaced relation with the heating element, and a temperature sensing device seated in the axial bore for detecting temperature changes as they occur in the spool and circuit to apply a voltage across the coil in response to detected drops in temperatures of the spool.

  20. ADAM -- Interface Module Reference Manual

    NASA Astrophysics Data System (ADS)

    Chipperfield, A. J.; Kelly, B. D.; Wright, S. L.

    ADAM Interface Modules provide an interface between ADAM application programs and the rest of the system. This document describes in detail the facilities available with ADAM Interface Modules and the rules for using them. It is intended as a reference manual and should shed light on some of the finer points of the ADAM parameter system. Readers requiring an introduction to Interface Modules should read SG/4.

  1. HANFORD WASTE MINEROLOGY REFERENCE REPORT

    SciTech Connect

    DISSELKAMP RS

    2010-06-18

    This report lists the observed mineral phase phases present in the Hanford tanks. This task was accomplished by performing a review of numerous reports using experimental techniques including, but not limited to: x-ray diffraction, polarized light microscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, electron energy loss spectroscopy, and particle size distribution analyses. This report contains tables that can be used as a quick reference to identify the crystal phases present observed in Hanford waste.

  2. HANFORD WASTE MINERALOGY REFERENCE REPORT

    SciTech Connect

    DISSELKAMP RS

    2010-06-29

    This report lists the observed mineral phases present in the Hanford tanks. This task was accomplished by performing a review of numerous reports that used experimental techniques including, but not limited to: x-ray diffraction, polarized light microscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, electron energy loss spectroscopy, and particle size distribution analyses. This report contains tables that can be used as a quick reference to identify the crystal phases observed in Hanford waste.

  3. National Software Reference Library (NSRL)

    National Institute of Standards and Technology Data Gateway

    National Software Reference Library (NSRL) (PC database for purchase)   A collaboration of the National Institute of Standards and Technology (NIST), the National Institute of Justice (NIJ), the Federal Bureau of Investigation (FBI), the Defense Computer Forensics Laboratory (DCFL),the U.S. Customs Service, software vendors, and state and local law enforement organizations, the NSRL is a tool to assist in fighting crime involving computers.

  4. Certified reference materials and reference methods for nuclear safeguards and security.

    PubMed

    Jakopič, R; Sturm, M; Kraiem, M; Richter, S; Aregbe, Y

    2013-11-01

    have therefore reached high level of attention for safeguards authorities. Furthermore, IRMM initiated and coordinated the development of a Modified Total Evaporation (MTE) technique for accurate abundance ratio measurements of the "minor" isotope-amount ratios of uranium and plutonium in nuclear material and, in combination with a multi-dynamic measurement technique and filament carburization, in environmental samples. Currently IRMM is engaged in a study on the development of plutonium reference materials for "age dating", i.e. determination of the time elapsed since the last separation of plutonium from its daughter nuclides. The decay of a radioactive parent isotope and the build-up of a corresponding amount of daughter nuclide serve as chronometer to calculate the age of a nuclear material. There are no such certified reference materials available yet.

  5. Genetics Home Reference: cerebrotendinous xanthomatosis

    MedlinePlus

    ... as substances called bile alcohols. Cholestanol and bile alcohols are increased in the blood, while blood cholesterol levels are typically ... Disorders Genetic and Rare Diseases Information Center (1 ...

  6. PVWatts Version 1 Technical Reference

    SciTech Connect

    Dobos, A. P.

    2013-10-01

    The NREL PVWatts(TM) calculator is a web application developed by the National Renewable Energy Laboratory (NREL) that estimates the electricity production of a grid-connected photovoltaic system based on a few simple inputs. PVWatts combines a number of sub-models to predict overall system performance, and makes several hidden assumptions about performance parameters. This technical reference details the individual sub-models, documents assumptions and hidden parameters, and explains the sequence of calculations that yield the final system performance estimation.

  7. Concepts in Geodetic Reference Frames.

    DTIC Science & Technology

    1979-10-01

    in the years 1900-1905. The period of C around the origin is about 1.2 years, the Chandler period. The z-axis of the terrestrial coordinate system is...multiplication by the matrix W which expresses the effect of polar motion, also called polar wobble . It has the form 1 0 x w= 0 1 -y (6-4) -x y 1 where...reference. The periods of forced rnotion (of F, H, and I) are about 1 day, the period of free motion of S, C’ and E0 around 0 is the Chandler period of

  8. World Reference Center for Arboviruses.

    DTIC Science & Technology

    1984-01-01

    flaviviruses recovered from pooled mosquitoes from Indonesia. Mous Reference Viruses JKT Arbo # Mouse immune ascitic fluids JE ME SEP THU ZIKA 5441 7180 9092...320 ɝ ɝ ɝ 5 Zika ( ZIKA ) 5 5 20 5 10 5 JKT Arbo # 5441 320 20 ɝ 160 ND 20 * ND not done F’, 41 r .• As more workers begin to use mosquito cells for...80 ɠ/4096 ᝺/81920 Zika 16/512 20/160 ɠ/4096 320/81920 Jutiapa 16/512 10/320 8/4096 160/81920 Yakose -- ɠ/4096 20/81920 Aroa -- ɠ/4096 ᝺/81920

  9. Ozone reference models for CIRA

    NASA Astrophysics Data System (ADS)

    Keating, G. M.; Young, D. F.; Pitts, M. C.

    The data bases and computational techniques used in recent models of the O3 distribution in the earth atmosphere are described, summarizing the results of ongoing efforts to define an O3 reference model for incorporation into CIRA. Consideration is given to the analysis of data from satellite instruments (Nimbus 7 LIMS, TOMS, and SBUV; SME UVS and IR; and AE-2 SAGE) to construct models of total column O3 and vertical O3 structure. The satellite-based model predictions are then compared with balloon, rocket, and umkehr measurements in extensive graphs: good agreement is demonstrated both among the satellite data sets and between satellite and nonsatellite data sets.

  10. Empirical Reference Models for COSPAR International Reference Atmosphere (CIRA)

    NASA Astrophysics Data System (ADS)

    Drob, Douglas; Emmert, John; Picone, Michael

    Openly distributed atmospheric reference models are an essential tool for scientific research and operational activities. To meet the needs of all users, such models must utilize rigorous statistical methods and the most comprehensive and reliable data sets in their development. Two such models that meet these requirements are the Naval Research Laboratory, Mass Spectrometer Incoherent Scatter Extended (NRLMSISE-00) and Horizontal Wind Model (HWM-93) empirical reference models. The NRLMSISE-00 model and its predecessors are based on 35 years of empirical modeling experience and over 40 years of research measurements. These global models are well documented and extend from the ground to the exosphere, providing estimates of neutral temperature, density, and major neutral species composition as a function of geographic location, day of year, time of day, and geomagnetic and solar activity conditions. Relative to the most comprehensive span of datasets available these models have the smallest bias and root mean square deviations of any climatological reference model built to date, although there are a few limitations in the 80 to 120 km region. The less advanced HWM-93 model, based on the same statistical methodologies and general mathematical formulation of the NRLMSISE-00 model, provides climatological estimates of the horizontal wind fields over the same variables and range of conditions as the NRLMSISE-00 model. The availability of several new long term data sets, including satellite wind measurements from the WINDII instrument onboard the UARS satellite, as well as ground-based optical Fabery-Perot measurements, provide the opportunity to make significant refinements to the existing model. Initial results from an improved HWM will be shown for altitudes between 100 and 500 km. Improvement in the model's ability to represent the seasonal changes, solar forcing, geomagnetic forcing, diurnal variation, and vertical structure of horizontal winds of the region is

  11. 40 CFR 1508.24 - Referring agency.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Referring agency. 1508.24 Section 1508.24 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.24 Referring agency. Referring agency means the federal agency which has referred any matter to the...

  12. Virtual Reference for a Real Public.

    ERIC Educational Resources Information Center

    McDermott, Irene E.

    1998-01-01

    Reviews World Wide Web sites useful as alternative resources for reference librarians. Sites described are: general reference; reference for kids and teens; regional interest for Southern California, including local foreign-language resources and local history sites; and interactive reference. (JAK)

  13. The Art of Collection Development: Reference Style.

    ERIC Educational Resources Information Center

    Schmitt, John P.

    1998-01-01

    Discusses selecting for a reference collection, creative budgeting, cutting a deal, collection awareness (strengths/needs), Web site reviews, R-Net (reviews from diverse areas and institutions), and print vs. electronic reference products. Reference librarian adhere to high standards for reference book and Web sites, teach assessment techniques,…

  14. Instant Messaging Reference: How Does It Compare?

    ERIC Educational Resources Information Center

    Desai, Christina M.

    2003-01-01

    Compares a digital reference service that uses instant messaging with traditional, face-to-face reference based on experiences at the Southern Illinois University library. Addresses differences in reference questions asked, changes in the reference transaction, student expectations, bibliographic instruction, and librarian attitudes and procedures…

  15. Building and Maintaining Digital Reference Services.

    ERIC Educational Resources Information Center

    Wasik, Joann M.

    2000-01-01

    Discusses digital reference services that provide subject expertise and information referral over the Internet to their users. Describes the history of digital reference, how digital reference services work, and explains a six-step process for building and maintaining digital reference services, including training, planning, and evaluating. (LRW)

  16. Reference electrodes for underground storage tanks

    SciTech Connect

    Ansuini, F.J.; Dimond, J.R.

    1995-12-31

    This paper discusses several factors affecting the reference potential established by copper/copper sulfate and silver/silver chloride reference electrodes. Guidelines for using permanent references in underground storage tank applications are presented and some causes of misleading readings with portable references are discussed.

  17. Resonance behaviour of whole-body averaged specific energy absorption rate (SAR) in the female voxel model, NAOMI

    NASA Astrophysics Data System (ADS)

    Dimbylow, Peter

    2005-09-01

    Finite-difference time-domain (FDTD) calculations have been performed of the whole-body averaged specific energy absorption rate (SAR) in a female voxel model, NAOMI, under isolated and grounded conditions from 10 MHz to 3 GHz. The 2 mm resolution voxel model, NAOMI, was scaled to a height of 1.63 m and a mass of 60 kg, the dimensions of the ICRP reference adult female. Comparison was made with SAR values from a reference male voxel model, NORMAN. A broad SAR resonance in the NAOMI values was found around 900 MHz and a resulting enhancement, up to 25%, over the values for the male voxel model, NORMAN. This latter result confirmed previously reported higher values in a female model. The effect of differences in anatomy was investigated by comparing values for 10-, 5- and 1-year-old phantoms rescaled to the ICRP reference values of height and mass which are the same for both sexes. The broad resonance in the NAOMI child values around 1 GHz is still a strong feature. A comparison has been made with ICNIRP guidelines. The ICNIRP occupational reference level provides a conservative estimate of the whole-body averaged SAR restriction. The linear scaling of the adult phantom using different factors in longitudinal and transverse directions, in order to match the ICRP stature and weight, does not exactly reproduce the anatomy of children. However, for public exposure the calculations with scaled child models indicate that the ICNIRP reference level may not provide a conservative estimate of the whole-body averaged SAR restriction, above 1.2 GHz for scaled 5- and 1-year-old female models, although any underestimate is by less than 20%.

  18. Hypertext Cross-Reference Utilities

    NASA Astrophysics Data System (ADS)

    Warren-Smith, R. F.; Draper, P. W.

    This document describes a set of ``Hypertext Cross-Reference Utilities'' (HTX) which are designed to help maintain large documentation sets whose constituent documents are written using the Hypertext Markup Languagee (HTML). The central part of HTX is a hypertext linker, hlink. This allows hyper-links (or cross-references) to be established between related documents in such a way that it is easy to maintain their integrity as individual documents are updated. Information produced by this linking process is also used by other HTX utilities to provide document search facilities and the ability to randomly access any part of a documentation set. This latter capability forms a basis for constructing hypertext help systems for use by other software. The expected readership of this document includes those who read hypertext documentation, those who write it, and those who maintain it, especially those who write and maintain Starlink documentation. Software developers may also be interested in the possibilities for hypertext help that HTX provides.

  19. Event boundaries and anaphoric reference.

    PubMed

    Thompson, Alexis N; Radvansky, Gabriel A

    2016-06-01

    The current study explored the finding that parsing a narrative into separate events impairs anaphor resolution. According to the Event Horizon Model, when a narrative event boundary is encountered, a new event model is created. Information associated with the prior event model is removed from working memory. So long as the event model containing the anaphor referent is currently being processed, this information should still be available when there is no narrative event boundary, even if reading has been disrupted by a working-memory-clearing distractor task. In those cases, readers may reactivate their prior event model, and anaphor resolution would not be affected. Alternatively, comprehension may not be as event oriented as this account suggests. Instead, any disruption of the contents of working memory during comprehension, event related or not, may be sufficient to disrupt anaphor resolution. In this case, reading comprehension would be more strongly guided by other, more basic language processing mechanisms and the event structure of the described events would play a more minor role. In the current experiments, participants were given stories to read in which we included, between the anaphor and its referent, either the presence of a narrative event boundary (Experiment 1) or a narrative event boundary along with a working-memory-clearing distractor task (Experiment 2). The results showed that anaphor resolution was affected by narrative event boundaries but not by a working-memory-clearing distractor task. This is interpreted as being consistent with the Event Horizon Model of event cognition.

  20. Reference-assisted chromosome assembly.

    PubMed

    Kim, Jaebum; Larkin, Denis M; Cai, Qingle; Asan; Zhang, Yongfen; Ge, Ri-Li; Auvil, Loretta; Capitanu, Boris; Zhang, Guojie; Lewin, Harris A; Ma, Jian

    2013-01-29

    One of the most difficult problems in modern genomics is the assembly of full-length chromosomes using next generation sequencing (NGS) data. To address this problem, we developed "reference-assisted chromosome assembly" (RACA), an algorithm to reliably order and orient sequence scaffolds generated by NGS and assemblers into longer chromosomal fragments using comparative genome information and paired-end reads. Evaluation of results using simulated and real genome assemblies indicates that our approach can substantially improve genomes generated by a wide variety of de novo assemblers if a good reference assembly of a closely related species and outgroup genomes are available. We used RACA to reconstruct 60 Tibetan antelope (Pantholops hodgsonii) chromosome fragments from 1,434 SOAPdenovo sequence scaffolds, of which 16 chromosome fragments were homologous to complete cattle chromosomes. Experimental validation by PCR showed that predictions made by RACA are highly accurate. Our results indicate that RACA will significantly facilitate the study of chromosome evolution and genome rearrangements for the large number of genomes being sequenced by NGS that do not have a genetic or physical map.

  1. Speaker Adaptation Using Multiple Reference Speakers

    DTIC Science & Technology

    1989-01-01

    to other methods that use a pooled reference model , this technique normalizes the training speech from multiple reference speakers to a single com...training the reference hidden Markov model (HMM). Our usual prohabilistic spectrum transformation can be applied to the reference HMM to model a new...trained phonetic hidden Markov models of a single reference speaker so that they were appropriate for a new (target) speaker. This method reduced the

  2. Demonstrating the comparability of certified reference materials.

    PubMed

    Duewer, David L; Lippa, Katrice A; Long, Stephen E; Murphy, Karen E; Sharpless, Katherine E; Sniegoski, Lorna T; Welch, Michael J; Tani, Wataru; Umemoto, Masao

    2009-09-01

    Certified reference materials (CRMs) enable the meaningful comparison of measurement results over time and place. When CRMs are used to calibrate or verify the performance of a measurement system, results produced by that system can be related through the CRM to well-defined, stable, and globally accessible reference(s). Properly done, this directly establishes the metrological traceability of the results. However, achieving the meaningful comparison of results from measurement systems calibrated and/or verified with different CRMs requires that the different materials truly deliver the same measurand, that is, are "the same" within stated uncertainty except for differences in the level of the analyte of interest. We here detail experimental and data analysis techniques for establishing and demonstrating the comparability of materials. We focus on (1) establishing a uniform interpretation of the common forms of CRM uncertainty statements, (2) estimating consistent measurement system response uncertainties from sometimes inconsistent experimental designs, (3) using "errors-in-variables" analysis methods to evaluate comparability studies and novel graphical tools for communicating results of the evaluation to reviewing authorities and potential CRM customers, and (4) augmenting established comparability studies with new materials using measurements provided by the certifying institution. These experimental and data analytic tools were developed in support of the Joint Committee for Traceability in Laboratory Medicine's efforts to enhance the reliability of clinical laboratory measurements and are illustrated with potassium and cholesterol measurands of clinical relevance; however, these tools can be applied to any group of materials that deliver the same nominal measurand with stated value and uncertainty.

  3. Comparing Virtual Reference Exit Survey Results and Transcript Analysis: A Model for Service Evaluation

    ERIC Educational Resources Information Center

    Smyth, Joanne B.; MacKenzie, James C.

    2006-01-01

    This study uses virtual reference transcripts for which patrons completed exit surveys to seek any correlations between user and librarian satisfaction within virtual reference transactions. By analyzing transcripts with a focus on three elements-technology performance, preferred reference practices, and the demonstrated communication levels of…

  4. Euclid mission: building of a reference survey

    NASA Astrophysics Data System (ADS)

    Amiaux, J.; Scaramella, R.; Mellier, Y.; Altieri, B.; Burigana, C.; Da Silva, Antonio; Gomez, P.; Hoar, J.; Laureijs, R.; Maiorano, E.; Magalhães Oliveira, D.; Renk, F.; Saavedra Criado, G.; Tereno, I.; Auguères, J. L.; Brinchmann, J.; Cropper, M.; Duvet, L.; Ealet, A.; Franzetti, P.; Garilli, B.; Gondoin, P.; Guzzo, L.; Hoekstra, H.; Holmes, R.; Jahnke, K.; Kitching, T.; Meneghetti, M.; Percival, W.; Warren, S.

    2012-09-01

    Euclid is an ESA Cosmic-Vision wide-field-space mission which is designed to explain the origin of the acceleration of Universe expansion. The mission will investigate at the same time two primary cosmological probes: Weak gravitational Lensing (WL) and Galaxy Clustering (in particular Baryon Acoustic Oscillations, BAO). The extreme precision requested on primary science objectives can only be achieved by observing a large number of galaxies distributed over the whole sky in order to probe the distribution of dark matter and galaxies at all scales. The extreme accuracy needed requires observation from space to limit all observational biases in the measurements. The definition of the Euclid survey, aiming at detecting billions of galaxies over 15 000 square degrees of the extragalactic sky, is a key parameter of the mission. It drives its scientific potential, its duration and the mass of the spacecraft. The construction of a Reference Survey derives from the high level science requirements for a Wide and a Deep survey. The definition of a main sequence of observations and the associated calibrations were indeed a major achievement of the Definition Phase. Implementation of this sequence demonstrated the feasibility of covering the requested area in less than 6 years while taking into account the overheads of space segment observing and maneuvering sequence. This reference mission will be used for sizing the spacecraft consumables needed for primary science. It will also set the framework for optimizing the time on the sky to fulfill the primary science and maximize the Euclid legacy.

  5. Mass storage system reference model, Version 4

    NASA Technical Reports Server (NTRS)

    Coleman, Sam (Editor); Miller, Steve (Editor)

    1993-01-01

    The high-level abstractions that underlie modern storage systems are identified. The information to generate the model was collected from major practitioners who have built and operated large storage facilities, and represents a distillation of the wisdom they have acquired over the years. The model provides a common terminology and set of concepts to allow existing systems to be examined and new systems to be discussed and built. It is intended that the model and the interfaces identified from it will allow and encourage vendors to develop mutually-compatible storage components that can be combined to form integrated storage systems and services. The reference model presents an abstract view of the concepts and organization of storage systems. From this abstraction will come the identification of the interfaces and modules that will be used in IEEE storage system standards. The model is not yet suitable as a standard; it does not contain implementation decisions, such as how abstract objects should be broken up into software modules or how software modules should be mapped to hosts; it does not give policy specifications, such as when files should be migrated; does not describe how the abstract objects should be used or connected; and does not refer to specific hardware components. In particular, it does not fully specify the interfaces.

  6. Reference condition approach to restoration planning

    USGS Publications Warehouse

    Nestler, J.M.; Theiling, C.H.; Lubinski, S.J.; Smith, D.L.

    2010-01-01

    Ecosystem restoration planning requires quantitative rigor to evaluate alternatives, define end states, report progress and perform environmental benefits analysis (EBA). Unfortunately, existing planning frameworks are, at best, semi-quantitative. In this paper, we: (1) describe a quantitative restoration planning approach based on a comprehensive, but simple mathematical framework that can be used to effectively apply knowledge and evaluate alternatives, (2) use the approach to derive a simple but precisely defined lexicon based on the reference condition concept and allied terms and (3) illustrate the approach with an example from the Upper Mississippi River System (UMRS) using hydrologic indicators. The approach supports the development of a scaleable restoration strategy that, in theory, can be expanded to ecosystem characteristics such as hydraulics, geomorphology, habitat and biodiversity. We identify three reference condition types, best achievable condition (A BAC), measured magnitude (MMi which can be determined at one or many times and places) and desired future condition (ADFC) that, when used with the mathematical framework, provide a complete system of accounts useful for goal-oriented system-level management and restoration. Published in 2010 by John Wiley & Sons, Ltd.

  7. Genetics Home Reference: androgenetic alopecia

    MedlinePlus

    ... a new hair. Increased levels of androgens in hair follicles can lead to a shorter cycle of hair ... lead to increased activity of androgen receptors in hair follicles. It remains unclear, however, how these genetic changes ...

  8. Genetics Home Reference: Canavan disease

    MedlinePlus

    ... infantile form of Canavan disease severely impair the enzyme's activity, allowing NAA to build up to high levels ... of the disorder have milder effects on the enzyme's activity, leading to less accumulation of NAA. An excess ...

  9. Genetics Home Reference: Donohue syndrome

    MedlinePlus

    ... is a rare disorder characterized by severe insulin resistance, a condition in which the body's tissues and ... cells to be used as energy. Severe insulin resistance leads to problems with regulating blood sugar levels ...

  10. Genetics Home Reference: beta thalassemia

    MedlinePlus

    ... a blood disorder that reduces the production of hemoglobin . Hemoglobin is the iron-containing protein in red blood ... In people with beta thalassemia , low levels of hemoglobin lead to a lack of oxygen in many ...

  11. Genetics Home Reference: isovaleric acidemia

    MedlinePlus

    ... certain proteins properly. It is classified as an organic acid disorder, which is a condition that leads ... an abnormal buildup of particular acids known as organic acids. Abnormal levels of organic acids in the ...

  12. Genetics Home Reference: propionic acidemia

    MedlinePlus

    ... lipids (fats) properly. It is classified as an organic acid disorder, which is a condition that leads ... an abnormal buildup of particular acids known as organic acids. Abnormal levels of organic acids in the ...

  13. NUCLEAR SCIENCE REFERENCES CODING MANUAL

    SciTech Connect

    WINCHELL,D.F.

    2007-04-01

    This manual is intended as a guide for Nuclear Science References (NSR) compilers. The basic conventions followed at the National Nuclear Data Center (NNDC), which are compatible with the maintenance and updating of and retrieval from the Nuclear Science References (NSR) file, are outlined. The NSR database originated at the Nuclear Data Project (NDP) at Oak Ridge National Laboratory as part of a project for systematic evaluation of nuclear structure data.1 Each entry in this computer file corresponds to a bibliographic reference that is uniquely identified by a Keynumber and is describable by a Topic and Keywords. It has been used since 1969 to produce bibliographic citations for evaluations published in Nuclear Data Sheets. Periodic additions to the file were published as the ''Recent References'' issues of Nuclear Data Sheets prior to 2005. In October 1980, the maintenance and updating of the NSR file became the responsibility of the NNDC at Brookhaven National Laboratory. The basic structure and contents of the NSR file remained unchanged during the transfer. In Chapter 2, the elements of the NSR file such as the valid record identifiers, record contents, and text fields are enumerated. Relevant comments regarding a new entry into the NSR file and assignment of a keynumber are also given in Chapter 2. In Chapter 3, the format for keyword abstracts is given followed by specific examples; for each TOPIC, the criteria for inclusion of an article as an entry into the NSR file as well as coding procedures are described. Authors preparing Keyword abstracts either to be published in a Journal (e.g., Nucl. Phys. A) or to be sent directly to NNDC (e.g., Phys. Rev. C) should follow the illustrations in Chapter 3. The scope of 1See W.B.Ewbank, ORNL-5397 (1978). the literature covered at the NNDC, the categorization into Primary and Secondary sources, etc., is discussed in Chapter 4. Useful information regarding permitted character sets, recommended abbreviations, etc., is

  14. Primary Atomic Clock Reference System

    NASA Technical Reports Server (NTRS)

    2001-01-01

    An artist's concept of the Primary Atomic Clock Reference System (PARCS) plarned to fly on the International Space Station (ISS). PARCS will make even more accurate atomic time available to everyone, from physicists testing Einstein's Theory of Relativity, to hikers using the Global Positioning System to find their way. In ground-based atomic clocks, lasers are used to cool and nearly stop atoms of cesium whose vibrations are used as the time base. The microgravity of space will allow the atoms to be suspended in the clock rather than circulated in an atomic fountain, as required on Earth. PARCS is being developed by the Jet Propulsion Laboratory with principal investigators at the National Institutes of Standards and Technology and the University of Colorado, Boulder. See also No. 0103191

  15. Primary Atomic Clock Reference System

    NASA Technical Reports Server (NTRS)

    2001-01-01

    An artist's concept of the Primary Atomic Clock Reference System (PARCS) plarned to fly on the International Space Station (ISS). PARCS will make even more accurate atomic time available to everyone, from physicists testing Einstein's Theory of Relativity, to hikers using the Global Positioning System to find their way. In ground-based atomic clocks, lasers are used to cool and nearly stop atoms of cesium whose vibrations are used as the time base. The microgravity of space will allow the atoms to be suspended in the clock rather than circulated in an atomic fountain, as required on Earth. PARCS is being developed by the Jet Propulsion Laboratory with principal investigators at the National Institutes of Standards and Technology and the University of Colorado, Boulder. See also No. 0100120.

  16. Dietary intake and anthropometric reference values in population studies.

    PubMed

    Arija, Victoria; Pérez Rodrigo, Carmen; Martínez de Vitoria, Emilio; Ortega, Rosa M; Serra-Majem, Luis; Ribas, Lourdes; Aranceta, Javier

    2015-02-26

    In nutritional epidemiology it is essential to have reference values for nutrition and anthropometry in order to compare individual and population data. With respect to reference nutritional intake, the new concept of Dietary Reference Intakes is generated based more on the prevention of chronic diseases than on covering nutritional deficiencies, as would occur in the early Recommendations. As such, the more relevant international organizations incorporated new concepts in their tables, such as the Adequate Intake levels or the Tolerable Upper Intake levels. Currently, the EURRECA recommendations (EURopean micronutrient RECommendations Aligned) are generating reference values for Europe in a transparent, systematic and scientific manner. Using the DRI, health-care authorities formulated nutritional objectives for countries or territories and Dietary Guides to disseminate the dietary advice to the population. Anthropometric assessment continues to be one of the most-used methods for evaluating and monitoring health status, nutritional state and growth in children, not only individuals but also communities. Different organizations have established anthropometric reference patterns of body mass index (BMI) with cut-off points to define overweight and obesity. In children, growth curves have been revised and adapted to the characteristics of healthy children in order to obtain anthropometric reference standards that better reflect optimum growth in children. The Growth Standards for children below 5 years of age of the WHO are a response to these principles, and are widely accepted and used worldwide.

  17. GLOBAL REFERENCE ATMOSPHERIC MODELS FOR AEROASSIST APPLICATIONS

    NASA Technical Reports Server (NTRS)

    Duvall, Aleta; Justus, C. G.; Keller, Vernon W.

    2005-01-01

    Aeroassist is a broad category of advanced transportation technology encompassing aerocapture, aerobraking, aeroentry, precision landing, hazard detection and avoidance, and aerogravity assist. The eight destinations in the Solar System with sufficient atmosphere to enable aeroassist technology are Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Saturn's moon Titan. Engineering-level atmospheric models for five of these targets - Earth, Mars, Titan, Neptune, and Venus - have been developed at NASA's Marshall Space Flight Center. These models are useful as tools in mission planning and systems analysis studies associated with aeroassist applications. The series of models is collectively named the Global Reference Atmospheric Model or GRAM series. An important capability of all the models in the GRAM series is their ability to simulate quasi-random perturbations for Monte Carlo analysis in developing guidance, navigation and control algorithms, for aerothermal design, and for other applications sensitive to atmospheric variability. Recent example applications are discussed.

  18. How accurate are quotations and references in medical journals?

    PubMed Central

    de Lacey, G; Record, C; Wade, J

    1985-01-01

    The accuracy of quotations and references in six medical journals published during January 1984 was assessed. The original author was misquoted in 15% of all references, and most of the errors would have misled readers. Errors in citation of references occurred in 24%, of which 8% were major errors--that is, they prevented immediate identification of the source of the reference. Inaccurate quotations and citations are displeasing for the original author, misleading for the reader, and mean that untruths become "accepted fact." Some suggestions for reducing these high levels of inaccuracy are that papers scheduled for publication with errors of citation should be returned to the author and checked completely and a permanent column specifically for misquotations could be inserted into the journal. PMID:3931753

  19. Very preliminary reference Moon model

    NASA Astrophysics Data System (ADS)

    Garcia, Raphaël F.; Gagnepain-Beyneix, Jeannine; Chevrot, Sébastien; Lognonné, Philippe

    2011-09-01

    The deep structure of the Moon is a missing piece to understand the formation and evolution of the Earth-Moon system. Despite the great amount of information brought by the Apollo passive seismic experiment (ALSEP), the lunar structure below deep moonquakes, which occur around 900 km depth, remains largely unknown. We construct a reference Moon model which incorporates physical constraints, and fits both geodesic (lunar mass and polar moment of inertia, and Love numbers) and seismological (body wave arrivals measured by Apollo network) data. In this model, the core radius is constrained by the detection of S waves reflected from the core. In a first step, for each core radius, a radial model of the lunar interior, including P and S wave velocities and density, is inverted from seismic and geodesic data. In a second step, the core radius is determined from the detection of shear waves reflected on the lunar core by waveform stacking of deep moonquake Apollo records. This detection has been made possible by careful data selection and processing, including a correction of the gain of horizontal sensors based on the principle of energy equipartition inside the coda of lunar seismic records, and a precise alignment of SH waveforms by a non-linear inversion method. The Very Preliminary REference MOON model (VPREMOON) obtained here has a core radius of 380 ± 40 km and an average core mass density of 5200 ± 1000 kg/m 3. The large error bars on these estimates are due to the poorly constrained S-wave velocity profile at the base of the mantle and to mislocation errors of deep moonquakes. The detection of horizontally polarized S waves reflected from the core and the absence of detection of vertically polarized S waves favour a liquid state in the outermost part of the core. All these results are consistent, within their error bars, with previous estimates based on lunar rotation dissipation ( Williams et al., 2001) and on lunar induced magnetic moment ( Hood et al., 1999).

  20. Reference materials for cellular therapeutics.

    PubMed

    Bravery, Christopher A; French, Anna

    2014-09-01

    The development of cellular therapeutics (CTP) takes place over many years, and, where successful, the developer will anticipate the product to be in clinical use for decades. Successful demonstration of manufacturing and quality consistency is dependent on the use of complex analytical methods; thus, the risk of process and method drift over time is high. The use of reference materials (RM) is an established scientific principle and as such also a regulatory requirement. The various uses of RM in the context of CTP manufacturing and quality are discussed, along with why they are needed for living cell products and the analytical methods applied to them. Relatively few consensus RM exist that are suitable for even common methods used by CTP developers, such as flow cytometry. Others have also identified this need and made proposals; however, great care will be needed to ensure any consensus RM that result are fit for purpose. Such consensus RM probably will need to be applied to specific standardized methods, and the idea that a single RM can have wide applicability is challenged. Written standards, including standardized methods, together with appropriate measurement RM are probably the most appropriate way to define specific starting cell types. The characteristics of a specific CTP will to some degree deviate from those of the starting cells; consequently, a product RM remains the best solution where feasible. Each CTP developer must consider how and what types of RM should be used to ensure the reliability of their own analytical measurements.

  1. A reference architecture for telemonitoring.

    PubMed

    Clarke, Malcolm

    2004-01-01

    The Telecare Interactive Continuous Monitoring System exploits GPRS to provide an ambulatory device that monitors selected vital signs on a continuous basis. Alarms are sent when parameters fall outside preset limits, and accompanying physiological data may also be transmitted. The always-connected property of GPRS allows continuous interactive control of the device and its sensors, permitting changes to monitoring parameters or even enabling continuous monitoring of a sensor in emergency. A new personal area network (PAN) has been developed to support short-range wireless connection to sensors worn on the body including ECG and finger worn SpO2. Most notable is use of ultra low radio frequency to reduce power to minimum. The system has been designed to use a hierarchical architecture for sensors and "derived" signals, such as HR from ECG, so that each can be independently controlled and managed. Sensors are treated as objects, and functions are defined to control aspects of behaviour. These are refined in order to define a generic set of abstract functions to handle the majority of functions, leaving a minimum of sensor specific commands. The intention is to define a reference architecture in order to research the functionality and system architecture of a telemonitoring system. The Telecare project is funded through a grant from the European Commission (IST programme).

  2. ILC cryogenic systems reference design

    SciTech Connect

    Peterson, T.J.; Geynisman, M.; Klebaner, A.; Theilacker, J.; Parma, V.; Tavian, L.; /CERN

    2008-01-01

    A Global Design Effort (GDE) began in 2005 to study a TeV scale electron-positron linear accelerator based on superconducting radio-frequency (RF) technology, called the International Linear Collider (ILC). In early 2007, the design effort culminated in a reference design for the ILC, closely based on the earlier TESLA design. The ILC will consist of two 250 GeV linacs, which provide positron-electron collisions for high energy physics research. The particle beams will be accelerated to their final energy in superconducting niobium RF cavities operating at 2 kelvin. At a length of about 12 km each, the main linacs will be the largest cryogenic systems in the ILC. Positron and electron sources, damping rings, and beam delivery systems will also have a large number and variety of other superconducting RF cavities and magnets, which require cooling at liquid helium temperatures. Ten large cryogenic plants with 2 kelvin refrigeration are envisioned to cool the main linacs and the electron and positron sources. Three smaller cryogenic plants will cool the damping rings and beam delivery system components predominately at 4.5 K. This paper describes the cryogenic systems concepts for the ILC.

  3. Establishment of reference standards in biosimilar studies.

    PubMed

    Zhang, Aijing; Tzeng, Jung-Ying; Chow, Shein-Chung

    2013-07-31

    When an innovative biological product goes off-patent, biopharmaceutical or biotechnological companies may file an application for regulatory approval of biosimilar products. In practice, however, important information on the innovative (reference) product may not be available for assessment. Thus, it is important to first establish a reference standard while assessing biosimilarity between a biosimilar product and the reference product. In this paper, reference standard is established through the biosimilarity index approach based on a reference-replicated study (or R-R study), in which the reference product is compared with itself under various scenarios. The reference standard can then be used for assessing the degree of similarity between the test and reference drugs in biosimilar studies.

  4. 33 CFR 242.3 - References.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false References. 242.3 Section 242.3 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE FLOOD PLAIN MANAGEMENT SERVICES PROGRAM ESTABLISHMENT OF FEES FOR COST RECOVERY § 242.3 References. The references...

  5. 33 CFR 242.3 - References.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false References. 242.3 Section 242.3 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE FLOOD PLAIN MANAGEMENT SERVICES PROGRAM ESTABLISHMENT OF FEES FOR COST RECOVERY § 242.3 References. The references...

  6. Suggested References. PACE I.D. Center.

    ERIC Educational Resources Information Center

    Bergson, Rita

    During the course of the PACE I.D. Center Project, 1966-1969, staff members recorded references that they felt contributed to the general knowledge of the prevention of learning and behavior problems. More specifically, those references that implied concern for the child in his total environment were considered most relevant. The references are…

  7. Virtual Reference Services: Directions and Agendas.

    ERIC Educational Resources Information Center

    Gray, Suzanne M.

    2000-01-01

    Analyzes Web sites of ten large research libraries in order to establish a basic understanding of how some major libraries are currently providing virtual reference services. Discusses centralization; email reference guidelines; creating a service economy; expanding hours of service; virtual users' needs; and real-time virtual reference.…

  8. Rethinking Job References: A Networking Challenge

    ERIC Educational Resources Information Center

    Muir, Clive

    2009-01-01

    Can job references play an active role in shaping one's career plans? Would individuals consider their references as part of their personal and professional network? Although most professionals may respond with a resounding "Yes, of course!" to these questions, the author realized that many of his students were skeptical about job references. To…

  9. Environmental Sciences Reference Sources. An Annotated Bibliography.

    ERIC Educational Resources Information Center

    McMartin, Mary I., Comp.

    This list of Environmental Sciences References Sources is intended to give undergraduate and graduate students a starting point when searching for information in the library. Entries are grouped according to type of reference material and then are listed in alphabetical order. The types of reference material included are guides to dictionaries,…

  10. Frames of Reference in the Classroom

    ERIC Educational Resources Information Center

    Grossman, Joshua

    2012-01-01

    The classic film "Frames of Reference" effectively illustrates concepts involved with inertial and non-inertial reference frames. In it, Donald G. Ivey and Patterson Hume use the cameras perspective to allow the viewer to see motion in reference frames translating with a constant velocity, translating while accelerating, and rotating--all with…

  11. Applying Information Competency to Digital Reference.

    ERIC Educational Resources Information Center

    Ellis, Lisa; Francoeur, Stephen

    This paper presents a case for applying information competency (IC) standards to digital reference services at academic libraries. Practical reasons for applying standards or guidelines to e-mail and online chat reference services are given with some insight to the nature of digital reference interactions. The standards that arose from the…

  12. Quality Standards for Digital Reference Consortia.

    ERIC Educational Resources Information Center

    Kasowitz, Abby; Bennett, Blythe; Lankes, R. David

    2000-01-01

    Identifies a working set of standards by which to assess individual digital reference services (Internet-based human-mediated information services) and to define membership within a collaborative network of digital reference services. The standards are designed for the Virtual Reference Desk AskA Consortium. (Author/LRW)

  13. Reference and the First Person Pronoun.

    ERIC Educational Resources Information Center

    Glock, Hans-Johann; Hacker, P. M. S.

    1996-01-01

    Maintains that deciding whether the first person pronoun is a referring expression requires clarity about the role of "I" and a detailed account of the notion of reference. It is concluded that "I" is a limiting case of reference, in which the possibility of referential failure and misidentification does not apply. (24…

  14. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference into... the availability of this material at NARA, call 202-741-6030, or go to:...

  15. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have been... information on the availability of this material at NARA, call 202-741-6030, or go to:...

  16. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have been... information on the availability of this material at NARA, call 202-741-6030, or go to:...

  17. 40 CFR 94.5 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Reference materials. 94.5 Section 94.5... Compression-Ignition Marine Engines § 94.5 Reference materials. We have incorporated by reference the... availability of this material at NARA, call 202-741-6030, or go to:...

  18. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference into... the availability of this material at NARA, call 202-741-6030, or go to:...

  19. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference into... the availability of this material at NARA, call 202-741-6030, or go to:...

  20. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have been... information on the availability of this material at NARA, call 202-741-6030, or go to:...

  1. Reference electrodes for aboveground storage tanks

    SciTech Connect

    Ansuini, F.J.; Dimond, J.R.

    1995-12-31

    This paper discusses several factors affecting the reference potential established by copper/copper sulfate and silver/silver chloride reference electrodes. Guidelines for using references in aboveground storage tank applications are presented and some causes of misleading readings are discussed.

  2. Using XML technologies to organize electronic reference resources.

    PubMed

    Huser, Vojtech; Del Fiol, Guilherme; Rocha, Roberto A

    2005-01-01

    Provision of access to reference electronic resources to clinicians is becoming increasingly important. We have created a framework for librarians to manage access to these resources at an enterprise level, rather than at the individual hospital libraries. We describe initial project requirements, implementation details, and some preliminary results.

  3. A Reference Grammar of Dutch, with Exercises and Key.

    ERIC Educational Resources Information Center

    Fehringer, Carol

    This textbook provides an accessible reference grammar of the Dutch language for English-speaking students of Dutch to help consolidate their knowledge through practical exercises on a whole range of grammatical topics. It is intended both for beginners and intermediate level students. Advanced learners of Dutch wishing to review particular…

  4. Phase inverter provides variable reference push-pull output

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Dual-transistor difference amplifier provides a push-pull output referenced to a dc potential which can be varied without affecting the signal levels. The amplifier is coupled with a feedback circuit which can vary the operating points of the transistors by equal amounts to provide the variable reference potentials.

  5. Evaluating Reference Services and Reference Personnel: Questions and Answers from the Literature.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    1994-01-01

    This bibliographic essay discusses a variety of items from the literature on the evaluation of reference services and reference personnel. A model for the evaluation process is presented on which the literature review is based. (Contains 48 references.) (LRW)

  6. Prehension synergies and control with referent hand configurations

    PubMed Central

    Friedman, Jason; Kim, Sun Wook; Feldman, Anatol G.; Zatsiorsky, Vladimir M.

    2010-01-01

    We used the framework of the equilibrium-point hypothesis (in its updated form based on the notion of referent configuration) to investigate the multi-digit synergies at two levels of a hypothetical hierarchy involved in prehensile actions. Synergies were analyzed at the thumb–virtual finger (VF) level (VF is an imaginary digit with the mechanical action equivalent to that of the four actual fingers) and at the individual finger level. The subjects performed very quick vertical movements of a handle into a target. A load could be attached off-center to provide a pronation or supination torque. In a few trials, the handle was unexpectedly fixed to the table and the digits slipped off the sensors. In such trials, the hand stopped at a higher vertical position and rotated into pronation or supination depending on the expected torque. The aperture showed non-monotonic changes with a large, fast decrease and further increase, ending up with a smaller distance between the thumb and the fingers as compared to unperturbed trials. Multi-digit synergies were quantified using indices of co-variation between digit forces and moments of force across unperturbed trials. Prior to the lifting action, high synergy indices were observed at the individual finger level while modest indices were observed at the thumb–VF level. During the lifting action, the synergies at the individual finger level disappeared while the synergy indices became higher at the thumb–VF level. The results support the basic premise that, within a given task, setting a referent configuration may be described with a few referent values of variables that influence the equilibrium state, to which the system is attracted. Moreover, the referent configuration hypothesis can help interpret the data related to the trade-off between synergies at different hierarchical levels. PMID:20033397

  7. Accurate Analysis of Array References

    DTIC Science & Technology

    1992-09-22

    This thesis addresses the problem of data dependence analysis, the base step in detecting loop level parallelism in scientific programs. Traditional...data dependence analysis research has concentrated on the simpler problem of affine memory disambiguation. Many algorithms have been developed that...can devise an experiment to test the effectiveness of affine memory disambiguation at approximating the full dependence problem. We discover that the

  8. Estimating reference nutrient criteria for Maryland ecoregions.

    PubMed

    Morgan, Raymond P; Kline, Kathleen M; Churchill, John B

    2013-03-01

    Management of stream nutrients is becoming increasingly important in order to protect both water quality and aquatic resources throughout the USA. Using an extensive water quality database from the long-term Maryland Biological Stream Survey (MBSS), we describe nutrient relationships to landscape characteristics as total nitrogen (TN) and total phosphorus (TP) of small-order, non-tidal streams in USEPA L2 and L3 ecoregions in Maryland and by MBSS stream order at the L2 and L3 ecoregion levels. To protect stream ecosystem integrity, preliminary reference nutrient estimates (TN and TP) as percentiles (25th of all stream reaches and 75th of stream reference reaches) for the six Maryland L3 ecoregions are: Blue Ridge TN 0.29 and 0.64 mg/L, TP 0.0065 and 0.0090 mg/L; Central Appalachians TN 0.40 and 1.0 mg/L, TP 0.0060 and 0.015 mg/L; Middle Atlantic Coastal Plains TN 0.93 and 2.5 mg/L, TP 0.094 and 0.065 mg/L; Northern Piedmont TN 1.6 and 1.8 mg/L, TP 0.010 and 0.015 mg/L; Ridge and Valley TN 0.40 and 0.98 mg/L, TP 0.0063 and 0.012 mg/L; and Southeastern Plains TN 0.33 and 0.82 mg/L, TP 0.016 and 0.042 mg/L. High levels of both TN and TP are present in many streams found in non-tidal watersheds associated with all Maryland ecoregions, but are especially elevated in the Northern Piedmont and Middle Atlantic Coastal Plain ecoregions, with the latter second-order streams (average TN > 2.9 mg/L) significantly higher than all other ecoregion-order combinations. Across all six ecoregions, mean nutrient loading for both TN and TP was generally equivalent in first-order streams to nutrient concentrations seen in both second- and third-order streams, indicating a definite need to increase efforts in preventing nutrients from entering first-order streams. Small-order stream nutrient levels are the drivers for subsequent TN and TP inputs into the upper freshwater tidal reaches of the Chesapeake Bay, resulting in a potential risk for altered estuarine ecosystems.

  9. Generic Argillite/Shale Disposal Reference Case

    SciTech Connect

    Zheng, Liange; Colon, Carlos Jové; Bianchi, Marco; Birkholzer, Jens

    2014-08-08

    Radioactive waste disposal in a deep subsurface repository hosted in clay/shale/argillite is a subject of widespread interest given the desirable isolation properties, geochemically reduced conditions, and widespread geologic occurrence of this rock type (Hansen 2010; Bianchi et al. 2013). Bianchi et al. (2013) provides a description of diffusion in a clay-hosted repository based on single-phase flow and full saturation using parametric data from documented studies in Europe (e.g., ANDRA 2005). The predominance of diffusive transport and sorption phenomena in this clay media are key attributes to impede radionuclide mobility making clay rock formations target sites for disposal of high-level radioactive waste. The reports by Hansen et al. (2010) and those from numerous studies in clay-hosted underground research laboratories (URLs) in Belgium, France and Switzerland outline the extensive scientific knowledge obtained to assess long-term clay/shale/argillite repository isolation performance of nuclear waste. In the past several years under the UFDC, various kinds of models have been developed for argillite repository to demonstrate the model capability, understand the spatial and temporal alteration of the repository, and evaluate different scenarios. These models include the coupled Thermal-Hydrological-Mechanical (THM) and Thermal-Hydrological-Mechanical-Chemical (THMC) models (e.g. Liu et al. 2013; Rutqvist et al. 2014a, Zheng et al. 2014a) that focus on THMC processes in the Engineered Barrier System (EBS) bentonite and argillite host hock, the large scale hydrogeologic model (Bianchi et al. 2014) that investigates the hydraulic connection between an emplacement drift and surrounding hydrogeological units, and Disposal Systems Evaluation Framework (DSEF) models (Greenberg et al. 2013) that evaluate thermal evolution in the host rock approximated as a thermal conduction process to facilitate the analysis of design options. However, the assumptions and the

  10. Standard Setting to an International Reference Framework: Implications for Theory and Practice

    ERIC Educational Resources Information Center

    Lim, Gad S.; Geranpayeh, Ardeshir; Khalifa, Hanan; Buckendahl, Chad W.

    2013-01-01

    Standard setting theory has largely developed with reference to a typical situation, determining a level or levels of performance for one exam for one context. However, standard setting is now being used with international reference frameworks, where some parameters and assumptions of classical standard setting do not hold. We consider the…

  11. Lower incisor inclination regarding different reference planes.

    PubMed

    Zataráin, Brenda; Avila, Josué; Moyaho, Angeles; Carrasco, Rosendo; Velasco, Carmen

    2016-09-01

    The purpose of this study was to assess the degree of lower incisor inclination with respect to different reference planes. It was an observational, analytical, longitudinal, prospective study conducted on 100 lateral cephalograms which were corrected according to the photograph in natural head position in order to draw the true vertical plane (TVP). The incisor mandibular plane angle (IMPA) was compensated to eliminate the variation of the mandibular plane growth type with the formula "FMApx.- 25 (FMA) + IMPApx. = compensated IMPA (IMPACOM)". As the data followed normal distribution determined by the KolmogorovSmirnov test, parametric tests were used for the statistical analysis, Ttest, ANOVA and Pearson coefficient correlation test. Statistical analysis was performed using a statistical significance of p <0.05. There is correlation between TVP and NB line (NB) (0.8614), Frankfort mandibular incisor angle (FMIA) (0.8894), IMPA (0.6351), Apo line (Apo) (0.609), IMPACOM (0.8895) and McHorris angle (MH) (0.7769). ANOVA showed statistically significant differences between the means for the 7 variables with 95% confidence level, P=0.0001. The multiple range test showed no significant difference among means: APoNB (0.88), IMPAMH (0.36), IMPANB (0.65), FMIAIMPACOM (0.01), FMIATVP (0.18), TVPIMPACOM (0.17). There was correlation among all reference planes. There were statistically significant differences among the means of the planes measured, except for IMPACOM, FMIA and TVP. The IMPA differed significantly from the IMPACOM. The compensated IMPA and the FMIA did not differ significantly from the TVP. The true horizontal plane was mismatched with Frankfort plane in 84% of the sample with a range of 19°. The true vertical plane is adequate for measuring lower incisor inclination.

  12. REFERENCE CASES FOR USE IN THE CEMENTITIOUS BARRIERS PARTNERSHIP

    SciTech Connect

    Langton, C

    2009-01-06

    The Cementitious Barriers Project (CBP) is a multidisciplinary cross cutting project initiated by the US Department of Energy (DOE) to develop a reasonable and credible set of tools to improve understanding and prediction of the structural, hydraulic and chemical performance of cementitious barriers used in nuclear applications. The period of performance is >100 years for operating facilities and > 1000 years for waste management. The CBP has defined a set of reference cases to provide the following functions: (1) a common set of system configurations to illustrate the methods and tools developed by the CBP, (2) a common basis for evaluating methodology for uncertainty characterization, (3) a common set of cases to develop a complete set of parameter and changes in parameters as a function of time and changing conditions, and (4) a basis for experiments and model validation, and (5) a basis for improving conceptual models and reducing model uncertainties. These reference cases include the following two reference disposal units and a reference storage unit: (1) a cementitious low activity waste form in a reinforced concrete disposal vault, (2) a concrete vault containing a steel high-level waste tank filled with grout (closed high-level waste tank), and (3) a spent nuclear fuel basin during operation. Each case provides a different set of desired performance characteristics and interfaces between materials and with the environment. Examples of concretes, grout fills and a cementitious waste form are identified for the relevant reference case configurations.

  13. REFERENCE CASES FOR USE IN THE CEMENTITOUS PARTNERSHIP PROJECT

    SciTech Connect

    Langton, C.; Kosson, D.; Garrabrants, A.

    2010-08-31

    The Cementitious Barriers Partnership Project (CBP) is a multi-disciplinary, multi-institution cross cutting collaborative effort supported by the US Department of Energy (DOE) to develop a reasonable and credible set of tools to improve understanding and prediction of the structural, hydraulic and chemical performance of cementitious barriers used in nuclear applications. The period of performance is >100 years for operating facilities and > 1000 years for waste management. The CBP has defined a set of reference cases to provide the following functions: (i) a common set of system configurations to illustrate the methods and tools developed by the CBP, (ii) a common basis for evaluating methodology for uncertainty characterization, (iii) a common set of cases to develop a complete set of parameter and changes in parameters as a function of time and changing conditions, (iv) a basis for experiments and model validation, and (v) a basis for improving conceptual models and reducing model uncertainties. These reference cases include the following two reference disposal units and a reference storage unit: (i) a cementitious low activity waste form in a reinforced concrete disposal vault, (ii) a concrete vault containing a steel high-level waste tank filled with grout (closed high-level waste tank), and (iii) a spent nuclear fuel basin during operation. Each case provides a different set of desired performance characteristics and interfaces between materials and with the environment. Examples of concretes, grout fills and a cementitious waste form are identified for the relevant reference case configurations.

  14. Importance of reference gene selection for articular cartilage mechanobiology studies

    PubMed Central

    Al-Sabah, A.; Stadnik, P.; Gilbert, S.J.; Duance, V.C.; Blain, E.J.

    2016-01-01

    Summary Objective Identification of genes differentially expressed in mechano-biological pathways in articular cartilage provides insight into the molecular mechanisms behind initiation and/or progression of osteoarthritis (OA). Quantitative PCR (qPCR) is commonly used to measure gene expression, and is reliant on the use of reference genes for normalisation. Appropriate validation of reference gene stability is imperative for accurate data analysis and interpretation. This study determined in vitro reference gene stability in articular cartilage explants and primary chondrocytes subjected to different compressive loads and tensile strain, respectively. Design The expression of eight commonly used reference genes (18s, ACTB, GAPDH, HPRT1, PPIA, RPL4, SDHA and YWHAZ) was determined by qPCR and data compared using four software packages (comparative delta-Ct method, geNorm, NormFinder and BestKeeper). Calculation of geometric means of the ranked weightings was carried out using RefFinder. Results Appropriate reference gene(s) for normalisation of mechanically-regulated transcript levels in articular cartilage tissue or isolated chondrocytes were dependent on experimental set-up. SDHA, YWHAZ and RPL4 were the most stable genes whilst glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and to a lesser extent Hypoxanthine-guanine phosphoribosyltransferase (HPRT), showed variable expression in response to load, demonstrating their unsuitability in such in vitro studies. The effect of using unstable reference genes to normalise the expression of aggrecan (ACAN) and matrix metalloproteinase 3 (MMP3) resulted in inaccurate quantification of these mechano-sensitive genes and erroneous interpretation/conclusions. Conclusion This study demonstrates that commonly used ‘reference genes’ may be unsuitable for in vitro cartilage chondrocyte mechanobiology studies, reinforcing the principle that careful validation of reference genes is essential prior to each experiment to

  15. Low-level exposure to radiofrequency electromagnetic fields: health effects and research needs.

    PubMed

    Repacholi, M H

    1998-01-01

    The World Health Organization (WHO), the International Commission on Non-Ionizing Radiation Protection (ICNIRP), and the German and Austrian Governments jointly sponsored an international seminar in November of 1996 on the biological effects of low-level radiofrequency (RF) electromagnetic fields. For purposes of this seminar, RF fields having frequencies only in the range of about 10 MHz to 300 GHz were considered. This is one of a series of scientific review seminars held under the International Electromagnetic Field (EMF) Project to identify any health hazards from EMF exposure. The scientific literature was reviewed during the seminar and expert working groups formed to provide a status report on possible health effects from exposure to low-level RF fields and identify gaps in knowledge requiring more research to improve health risk assessments. It was concluded that, although hazards from exposure to high-level (thermal) RF fields were established, no known health hazards were associated with exposure to RF sources emitting fields too low to cause a significant temperature rise in tissue. Biological effects from low-level RF exposure were identified needing replication and further study. These included in vitro studies of cell kinetics and proliferation effects, effects on genes, signal transduction effects and alterations in membrane structure and function, and biophysical and biochemical mechanisms for RF field effects. In vivo studies should focus on the potential for cancer promotion, co-promotion and progression, as well as possible synergistic, genotoxic, immunological, and carcinogenic effects associated with chronic low-level RF exposure. Research is needed to determine whether low-level RF exposure causes DNA damage or influences central nervous system function, melatonin synthesis, permeability of the blood brain barrier (BBB), or reaction to neurotropic drugs. Reported RF-induced changes to eye structure and function should also be investigated

  16. In situ LTE exposure of the general public: Characterization and extrapolation.

    PubMed

    Joseph, Wout; Verloock, Leen; Goeminne, Francis; Vermeeren, Günter; Martens, Luc

    2012-09-01

    In situ radiofrequency (RF) exposure of the different RF sources is characterized in Reading, United Kingdom, and an extrapolation method to estimate worst-case long-term evolution (LTE) exposure is proposed. All electric field levels satisfy the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference levels with a maximal total electric field value of 4.5 V/m. The total values are dominated by frequency modulation (FM). Exposure levels for LTE of 0.2 V/m on average and 0.5 V/m maximally are obtained. Contributions of LTE to the total exposure are limited to 0.4% on average. Exposure ratios from 0.8% (LTE) to 12.5% (FM) are obtained. An extrapolation method is proposed and validated to assess the worst-case LTE exposure. For this method, the reference signal (RS) and secondary synchronization signal (S-SYNC) are measured and extrapolated to the worst-case value using an extrapolation factor. The influence of the traffic load and output power of the base station on in situ RS and S-SYNC signals are lower than 1 dB for all power and traffic load settings, showing that these signals can be used for the extrapolation method. The maximal extrapolated field value for LTE exposure equals 1.9 V/m, which is 32 times below the ICNIRP reference levels for electric fields.

  17. Quantum metrology in coarsened measurement reference

    NASA Astrophysics Data System (ADS)

    Xie, Dong; Xu, Chunling; Wang, An Min

    2017-01-01

    We investigate the role of coarsened measurement reference, which originates from the coarsened reference time and basis, in quantum metrology. When the measurement is based on one common reference basis, the disadvantage of coarsened measurement can be removed by symmetry. Owing to the coarsened reference basis, the entangled state cannot perform better than the product state for a large number of probe particles in estimating the phase. Given a finite uncertainty of the coarsened reference basis, the optimal number of probe particles is obtained. Finally, we prove that the maximally entangled state always achieves better frequency precision in the case of non-Markovian dephasing than that in the case of Markovian dephasing. The product state is more resistant to the interference of the coarsened reference time than the entangled state.

  18. Generating Ground Reference Data for a Global Impervious Surface Survey

    NASA Technical Reports Server (NTRS)

    Tilton, James C.; De Colstoun, Eric Brown; Wolfe, Robert E.; Tan, Bin; Huang, Chengquan

    2012-01-01

    We are developing an approach for generating ground reference data in support of a project to produce a 30m impervious cover data set of the entire Earth for the years 2000 and 2010 based on the Landsat Global Land Survey (GLS) data set. Since sufficient ground reference data for training and validation is not available from ground surveys, we are developing an interactive tool, called HSegLearn, to facilitate the photo-interpretation of 1 to 2 m spatial resolution imagery data, which we will use to generate the needed ground reference data at 30m. Through the submission of selected region objects and positive or negative examples of impervious surfaces, HSegLearn enables an analyst to automatically select groups of spectrally similar objects from a hierarchical set of image segmentations produced by the HSeg image segmentation program at an appropriate level of segmentation detail, and label these region objects as either impervious or nonimpervious.

  19. ["Pro Ana": Psychodynamic References for Anorexia Nervosa].

    PubMed

    Siefert, Linda

    2017-02-01

    "Pro Ana": Psychodynamic References for Anorexia Nervosa The internet-based phenomenon "Pro Ana" refers to the eating disorder anorexia nervosa in a positive way. To understand what the phenomenon "Pro Ana" represents, the websites are used as a starting point of the current analysis. Based on these results, similarities and differences between "Pro Ana" and the eating disorder anorexia nervosa are discussed. Furthermore psychodynamic references for anorexia nervosa are derived and finally their importance for treatment motivation will be considered.

  20. Biological and environmental reference materials: Update 1996

    NASA Astrophysics Data System (ADS)

    Roelandts, Iwan

    1997-07-01

    The present column lists additional biological and environmental reference samples. Organs, tissues, body fluids, plant materials, foods, fuels, ashes, dusts, particulate matter, gas mixtures, oils, soils, sediments, sludges and waters have been considered. Three tables are included that provide an easy-to-use survey. The following information is covered: the name of the material, the sample code, the producer, the reference to certification, the names and addresses of the suppliers from whom the reference material may be obtained, and specific remarks.

  1. An improved hypothetical reference decoder for HEVC

    NASA Astrophysics Data System (ADS)

    Deshpande, Sachin; Hannuksela, Miska M.; Kazui, Kimihiko; Schierl, Thomas

    2013-02-01

    Hypothetical Reference Decoder is a hypothetical decoder model that specifies constraints on the variability of conforming network abstraction layer unit streams or conforming byte streams that an encoding process may produce. High Efficiency Video Coding (HEVC) builds upon and improves the design of the generalized hypothetical reference decoder of H.264/ AVC. This paper describes some of the main improvements of hypothetical reference decoder of HEVC.

  2. Determining the Temperature Coefficient of Reference Resistors

    NASA Astrophysics Data System (ADS)

    Bojkovski, J.; Batagelj, V.; Žužek, V.

    2017-04-01

    The influence of temperature on electrical resistance of standard resistors is presented within this paper. Electrical resistance is like any other quantity temperature dependent. This dependence is specified with the temperature coefficient, which gives the relative change of resistance with temperature. The level of resistance change is not linear as it changes with temperature, and therefore the coefficient is temperature dependent as well. At a certain temperature, its value is equal to zero—the stationary point. Use of the standard resistor at this exact temperature or in a narrow interval around it greatly reduces the influence of temperature on electrical resistance, even if the thermal conditions are not optimal. Measurements of temperature coefficient were taken on a group of standard resistors of the same type in a wide temperature range, and the temperature of the stationary point was determined. Measurements were taken by placing the resistors in an oil bath and changing its set point temperature from 18°C to 38°C. Electrical resistance of each resistor was measured using a resistance bridge, which had its reference resistor placed in a separate thermal enclosure at a constant temperature.

  3. The NASA master directory: Quick reference guide

    NASA Technical Reports Server (NTRS)

    Satin, Karen (Editor); Kanga, Carol (Editor)

    1989-01-01

    This is a quick reference guide to the NASA Master Directory (MD), which is a free, online, multidisciplinary directory of space and Earth science data sets (NASA and non-NASA data) that are of potential interest to the NASA-sponsored research community. The MD contains high-level descriptions of data sets, other data systems and archives, and campaigns and projects. It provides mechanisms for searching for data sets by important criteria such as geophysical parameters, time, and spatial coverage, and provides information on ordering the data. It also provides automatic connections to a number of data systems such as the NASA Climate Data System, the Planetary Data System, the NASA Ocean Data System, the Pilot Land Data System, and others. The MD includes general information about many data systems, data centers, and coordinated data analysis projects, It represents the first major step in the Catalog Interoperability project, whose objective is to enable researchers to quickly and efficiently identify, obtain information about, and get access to space and Earth science data. The guide describes how to access, use, and exit the MD and lists its features.

  4. Resources and References for Earth Science Teachers

    ERIC Educational Resources Information Center

    Wall, Charles A.; Wall, Janet E.

    1976-01-01

    Listed are resources and references for earth science teachers including doctoral research, new textbooks, and professional literature in astronomy, space science, earth science, geology, meteorology, and oceanography. (SL)

  5. Assessment of induced SAR in children exposed to electromagnetic plane waves between 10 MHz and 5.6 GHz.

    PubMed

    Bakker, J F; Paulides, M M; Christ, A; Kuster, N; van Rhoon, G C

    2010-06-07

    To avoid potentially adverse health effects of electromagnetic fields (EMF), the International Commission on Non-Ionizing Radiation Protection (ICNIRP) has defined EMF reference levels from the basic restrictions on the induced whole-body-averaged specific absorption rate (SAR(wb)) and the peak 10 g spatial-averaged SAR (SAR(10g)). The objective of this study is to assess if the SAR in children remains below the basic restrictions upon exposure at the reference levels. Finite difference time domain (FDTD) modeling was used to calculate the SAR in six children and two adults when exposed to all 12 orthogonal plane wave configurations. A sensitivity study showed an expanded uncertainty of 53% (SAR(wb)) and 58% (SAR(10g)) due to variations in simulation settings and tissue properties. In this study, we found that the basic restriction on the SAR(wb) is occasionally exceeded for children, up to a maximum of 45% in small children. The maximum SAR(10g) values, usually found at body protrusions, remain under the limit for all scenarios studied. Our results are in good agreement with the literature, suggesting that the recommended ICNIRP reference levels may need fine tuning.

  6. Assessment of induced SAR in children exposed to electromagnetic plane waves between 10 MHz and 5.6 GHz

    NASA Astrophysics Data System (ADS)

    Bakker, J. F.; Paulides, M. M.; Christ, A.; Kuster, N.; van Rhoon, G. C.

    2010-06-01

    To avoid potentially adverse health effects of electromagnetic fields (EMF), the International Commission on Non-Ionizing Radiation Protection (ICNIRP) has defined EMF reference levels from the basic restrictions on the induced whole-body-averaged specific absorption rate (SARwb) and the peak 10 g spatial-averaged SAR (SAR10g). The objective of this study is to assess if the SAR in children remains below the basic restrictions upon exposure at the reference levels. Finite difference time domain (FDTD) modeling was used to calculate the SAR in six children and two adults when exposed to all 12 orthogonal plane wave configurations. A sensitivity study showed an expanded uncertainty of 53% (SARwb) and 58% (SAR10g) due to variations in simulation settings and tissue properties. In this study, we found that the basic restriction on the SARwb is occasionally exceeded for children, up to a maximum of 45% in small children. The maximum SAR10g values, usually found at body protrusions, remain under the limit for all scenarios studied. Our results are in good agreement with the literature, suggesting that the recommended ICNIRP reference levels may need fine tuning.

  7. The equations of relative motion in the orbital reference frame

    NASA Astrophysics Data System (ADS)

    Casotto, Stefano

    2016-03-01

    of the node and the argument of perigee, i.e., of the entire orbital plane. Here we provide a derivation of the exact equations of relative motion by expressing the angular velocity of the RTN frame in terms of the state vector of the reference spacecraft. As such, these equations are completely general, in the sense that the orbit of the reference spacecraft need only be known through its ephemeris, and therefore subject to any force field whatever. It is also shown that these equations reduce to either the Hill-Clohessy-Wiltshire, or the Tschauner-Hempel equations, depending on the level of approximation. The explicit form of the equations of relative motion with respect to a J_2-perturbed reference orbit is also introduced.

  8. Reference genes for normalizing transcription in diploid and tetraploid Arabidopsis.

    PubMed

    Wang, Haibin; Wang, Jingjing; Jiang, Jiafu; Chen, Sumei; Guan, Zhiyong; Liao, Yuan; Chen, Fadi

    2014-10-27

    Published transcription data from a set of 19 diploid Arabidopsis thaliana and 5 tetraploid (3 allo- and 2 auto- tetraploid) Arabidopsis accessions were re-analysed to identify reliable reference genes for normalization purposes. Five conventional and 16 novel reference genes previously derived from microarray data covering a wide range of abundance in absolute expression levels in diploid A. thaliana Col-0 were employed. Transcript abundance was well conserved for all 21 potential reference genes in the diploid A. thaliana accessions, with geNorm and NormFinder analysis indicating that AT5G46630, AT1G13320, AT4G26410, AT5G60390 and AT5G08290 were the most stable. However, conservation was less good among the tetraploid accessions, with the transcription of seven of the 21 genes being undetectable in all allotetraploids. The most stable gene was AT5G46630, while AT1G13440 was the unstable one. Hence, the choice of reference gene(s) for A. thaliana is quite wide, but with respect to the analysis of transcriptomic data derived from the tetraploids, it is probably necessary to select more than one reference gene.

  9. A First Look at the Upcoming SISO Space Reference FOM

    NASA Technical Reports Server (NTRS)

    Crues, Edwin; Dexter, Dan; Madden, Michael; Garro, Alfred; Vankov, Alexander; Skuratovskiy, Anton; Moller, Bjorn

    2016-01-01

    Simulation is increasingly used in the space domain for several purposes. One example is analysis and engineering, from the mission level down to individual systems and subsystems. Another example is training of space crew and flight controllers. Several distributed simulations have been developed for example for docking vehicles with the ISS and for mission training, in many cases with participants from several nations. Space based scenarios are also used in the "Simulation Exploration Experience", SISO's university outreach program. We have thus realized that there is a need for a distributed simulation interoperability standard for data exchange within the space domain. Based on these experiences, SISO is developing a Space Reference FOM. Members of the product development group come from several countries and contribute experiences from projects within NASA, ESA and other organizations. Participants represent government, academia and industry. The first version will focus on handling of time and space. The Space Reference FOM will provide the following: (i) a flexible positioning system using reference frames for arbitrary bodies in space, (ii) a naming conventions for well known reference frames, (iii) definitions of common time scales, (iv) federation agreements for common types of time management with focus on time stepped simulation, and (v) support for physical entities, such as space vehicles and astronauts. The Space Reference FOM is expected to make collaboration politically, contractually and technically easier. It is also expected to make collaboration easier to manage and extend.

  10. CRYSTALLINE CERAMIC WASTE FORMS: REFERENCE FORMULATION REPORT

    SciTech Connect

    Brinkman, K.; Fox, K.; Marra, J.

    2012-05-15

    The research conducted in this work package is aimed at taking advantage of the long term thermodynamic stability of crystalline ceramics to create more durable waste forms (as compared to high level waste glass) in order to reduce the reliance on engineered and natural barrier systems. Durable ceramic waste forms that incorporate a wide range of radionuclides have the potential to broaden the available disposal options and to lower the storage and disposal costs associated with advanced fuel cycles. Assemblages of several titanate phases have been successfully demonstrated to incorporate radioactive waste elements, and the multiphase nature of these materials allows them to accommodate variation in the waste composition. Recent work has shown that they can be successfully produced from a melting and crystallization process. The objective of this report is to explain the design of ceramic host systems culminating in a reference ceramic formulation for use in subsequent studies on process optimization and melt property data assessment in support of FY13 melter demonstration testing. The waste stream used as the basis for the development and testing is a combination of the projected Cs/Sr separated stream, the Trivalent Actinide - Lanthanide Separation by Phosphorous reagent Extraction from Aqueous Komplexes (TALSPEAK) waste stream consisting of lanthanide fission products, the transition metal fission product waste stream resulting from the transuranic extraction (TRUEX) process, and a high molybdenum concentration with relatively low noble metal concentrations. In addition to the combined CS/LN/TM High Mo waste stream, variants without Mo and without Mo and Zr were also evaluated. Based on the results of fabricating and characterizing several simulated ceramic waste forms, two reference ceramic waste form compositions are recommended in this report. The first composition targets the CS/LN/TM combined waste stream with and without Mo. The second composition targets

  11. Reference design description for a geologic repository: Revision 01

    SciTech Connect

    1997-09-01

    This document describes the current design expectations for a potential geologic repository that could be located at Yucca Mountain in Nevada. This Reference Design Description (RDD) looks at the surface and subsurface repository and disposal container design. Additionally, it reviews the expected long-term performance of the potential repository. In accordance with current legislation, the reference design for the potential repository does not include an interim storage option. The reference design presented allows the disposal of highly radioactive material received from government-owned spent fuel custodian sites; produces high-level waste sites, and commercial spent fuel sites. All design elements meet current federal, state, and local regulations governing the disposal of high-level radioactive waste and protection of the public and the environment. Due to the complex nature of developing a repository, the design will be created in three phases to support Viability Assessment, License Application, and construction. This document presents the current reference design. It will be updated periodically as the design progresses. Some of the details presented here may change significantly as more cost-effective solutions, technical advancements, or changes to requirements are identified.

  12. Triglyceride level

    MedlinePlus

    ... levels may be due to: Low fat diet Hyperthyroidism (overactive thyroid) Malabsorption syndrome (conditions in which the ... Familial lipoprotein lipase deficiency High blood cholesterol levels Hyperthyroidism Hypothyroidism Malabsorption Metabolism Nephrotic syndrome Protein in diet ...

  13. 44 CFR 59.4 - References.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... INSURANCE AND HAZARD MITIGATION National Flood Insurance Program GENERAL PROVISIONS General § 59.4 References. (a) The following are statutory references for the National Flood Insurance Program, under which these regulations are issued: (1) National Flood Insurance Act of 1968 (title XIII of the Housing...

  14. 44 CFR 59.4 - References.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... INSURANCE AND HAZARD MITIGATION National Flood Insurance Program GENERAL PROVISIONS General § 59.4 References. (a) The following are statutory references for the National Flood Insurance Program, under which these regulations are issued: (1) National Flood Insurance Act of 1968 (title XIII of the Housing...

  15. 4 CFR 2.2 - References.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 4 Accounts 1 2012-01-01 2012-01-01 false References. 2.2 Section 2.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM PURPOSE AND GENERAL PROVISION § 2.2 References. (a) Subchapters III and IV of Chapter 7 of Title 31 U.S.C. (b) Title 5, United States Code....

  16. 4 CFR 2.2 - References.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 4 Accounts 1 2014-01-01 2013-01-01 true References. 2.2 Section 2.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM PURPOSE AND GENERAL PROVISION § 2.2 References. (a) Subchapters III and IV of Chapter 7 of Title 31 U.S.C. (b) Title 5, United States Code....

  17. 4 CFR 2.2 - References.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 4 Accounts 1 2013-01-01 2013-01-01 false References. 2.2 Section 2.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM PURPOSE AND GENERAL PROVISION § 2.2 References. (a) Subchapters III and IV of Chapter 7 of Title 31 U.S.C. (b) Title 5, United States Code....

  18. RASD's New Interlibrary Reference Request Form.

    ERIC Educational Resources Information Center

    American Libraries, 1985

    1985-01-01

    Introduces information request form developed by Cooperative Reference Services Committee of American Library Association's Reference and Adult Services Division to be used whenever a library cannot supply information requested by a patron and would like to ask another library for assistance. Front of proposed form with sample question is shown.…

  19. Uncertainty in Reference and Information Service

    ERIC Educational Resources Information Center

    VanScoy, Amy

    2015-01-01

    Introduction: Uncertainty is understood as an important component of the information seeking process, but it has not been explored as a component of reference and information service. Method: Interpretative phenomenological analysis was used to examine the practitioner perspective of reference and information service for eight academic research…

  20. 40 CFR 1066.710 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Practice for Measuring Fuel Economy and Emissions of Hybrid-Electric and Conventional Heavy-Duty Vehicles, Issued September 2002, IBR approved for § 1066.501. (c) National Institute of Standards and Technology... VEHICLE-TESTING PROCEDURES Definitions and Other Reference Material § 1066.710 Reference materials....

  1. Economics: A Guide to Reference Sources.

    ERIC Educational Resources Information Center

    Mason, Mary, Comp.

    Approximately 84 reference materials on economics located in the McLennan Library, McGill University (Montreal), are cited in this annotated bibliography. The bibliography serves to provide an overview of the printed bibliographic and reference sources useful for the study of economics. Financial and business sources and statistical compendia and…

  2. Reference. Advisory List of Instructional Media.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Education, Raleigh.

    The reference books featured in this annotated bibliography were selected from those titles that publishers submitted to the North Carolina Department of Public Instruction for review. As such, it is not a comprehensive list of all reference titles in print. This guide organizes the 33 titles into major subject categories: (1) Arts…

  3. Reference Services Planning in the 90s.

    ERIC Educational Resources Information Center

    Eckwright, Gail Z., Ed.; Keenan, Lori M., Ed.

    The focus of this collection of papers about library reference service is on the community outside the library, rather than the special populations served within it. "Conflicts in Value Systems" (Allen B. Veaner) is an overview of the major conflict areas facing the library profession today. "Reference Services for Off-Campus…

  4. Invoking Digital Reference: Creation and Implementation

    ERIC Educational Resources Information Center

    Johnson, Wendell; Burke, Adam

    2003-01-01

    In response to the changing educational landscape of the community college, reference librarians must adapt their service to fit the information needs of their patrons. One such update is synchronous digital reference, which applies instant messaging technology to library service. Todd Library at Waubonsee Community College (Sugar Grove, Illinois)…

  5. 32 CFR 1290.1 - References.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false References. 1290.1 Section 1290.1 National Defense Other Regulations Relating to National Defense DEFENSE LOGISTICS AGENCY MISCELLANEOUS PREPARING AND PROCESSING MINOR OFFENSES AND VIOLATION NOTICES REFERRED TO U.S. DISTRICT COURTS §...

  6. 4 CFR 2.2 - References.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 4 Accounts 1 2011-01-01 2011-01-01 false References. 2.2 Section 2.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM PURPOSE AND GENERAL PROVISION § 2.2 References. (a) Subchapters III and IV of Chapter 7 of Title 31 U.S.C. (b) Title 5, United States Code....

  7. 4 CFR 2.2 - References.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 4 Accounts 1 2010-01-01 2010-01-01 false References. 2.2 Section 2.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM PURPOSE AND GENERAL PROVISION § 2.2 References. (a) Subchapters III and IV of Chapter 7 of Title 31 U.S.C. (b) Title 5, United States Code....

  8. So You Want To Do Virtual Reference?

    ERIC Educational Resources Information Center

    Coffman, Steve

    2001-01-01

    Examines the practical details of setting up live online reference services in libraries. Topics include choosing software; differences between licensed and hosted applications; models used to implement virtual reference services; how libraries are using these services in day to day operations; and marketing strategies. (Author/LRW)

  9. Going Prime Time with Live Chat Reference.

    ERIC Educational Resources Information Center

    Hoag, Tara J.; Cichanowicz, Edana McCaffrey

    2001-01-01

    Describes the development of the Suffolk Cooperative Library System's live, online chat reference service, a pilot project for public libraries in Suffolk County (New York). Topics include chat software selection; a virtual reference collection; marketing; funding; staffing; evaluation; expanded hours of service; email; and extracting data from…

  10. Ensuring Quality in a Virtual Reference Environment

    ERIC Educational Resources Information Center

    Barbier, Pat; Ward, Joyce

    2004-01-01

    Soon after AskALibrarian, Florida's Statewide Virtual Reference Desk, began to offer Chat Reference to the public in 2003, a Quality Assurance Workgroup was established to ensure that the service patrons received would be friendly, accurate, and adequate. To make certain that best practices were used in answering the real time questions, two…

  11. Reference Service in the Information Network.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    Reference service is defined as the mediation by a librarian between the need structures of users and the structures of information resources. The general process by which reference librarians accomplish this is outlined as including the phases of question clarification, question translation, search strategy formulation, search execution, delivery…

  12. Responsive Reference Service: Breaking Down Age Barriers.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    1994-01-01

    Examines possible barriers to adequate reference services to children and young adults. Topics discussed include the effects of budget pressures and shifting priorities in public and academic libraries; equity in access to information; reference policies; communication between children and adult services staff and administration; multiple service…

  13. Search Analysts as Successful Reference Librarians.

    ERIC Educational Resources Information Center

    Hammer, Mary M.

    1981-01-01

    Examines five factors critical to the successful functioning of search analysts as reference librarians: professional training, background knowledge and working experience in references services, personality characteristics and interpersonal skills, the marketing of online services, and patron evaluations supplemented by postsearch reference…

  14. 21 CFR 660.52 - Reference preparations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Reference preparations. 660.52 Section 660.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... preparations. Reference Anti-Human Globulin preparations shall be obtained from the Center for...

  15. 21 CFR 660.52 - Reference preparations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Reference preparations. 660.52 Section 660.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... preparations. Reference Anti-Human Globulin preparations shall be obtained from the Center for...

  16. 21 CFR 660.52 - Reference preparations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Reference preparations. 660.52 Section 660.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... preparations. Reference Anti-Human Globulin preparations shall be obtained from the Center for...

  17. 21 CFR 660.52 - Reference preparations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Reference preparations. 660.52 Section 660.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... preparations. Reference Anti-Human Globulin preparations shall be obtained from the Center for...

  18. 21 CFR 660.52 - Reference preparations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Reference preparations. 660.52 Section 660.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... preparations. Reference Anti-Human Globulin preparations shall be obtained from the Center for...

  19. 32 CFR 518.2 - References.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 3 2012-07-01 2009-07-01 true References. 518.2 Section 518.2 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS THE FREEDOM OF INFORMATION ACT PROGRAM General Provisions § 518.2 References. Required and...

  20. 32 CFR 518.2 - References.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 3 2011-07-01 2009-07-01 true References. 518.2 Section 518.2 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS THE FREEDOM OF INFORMATION ACT PROGRAM General Provisions § 518.2 References. Required and...