WorldWideScience

Sample records for volume emission rates

  1. Variability of OH(3-1) and OH(6-2) emission altitude and volume emission rate from 2003 to 2011

    Science.gov (United States)

    Teiser, Georg; von Savigny, Christian

    2017-08-01

    In this study we report on variability in emission rate and centroid emission altitude of the OH(3-1) and OH(6-2) Meinel bands in the terrestrial nightglow based on spaceborne nightglow measurements with the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) instrument on the Envisat satellite. The SCIAMACHY observations cover the time period from August 2002 to April 2012 and the nighttime observations used in this study are performed at 10:00 p.m. local solar time. Characterizing variability in OH emission altitude - particularly potential long-term variations - is important for an appropriate interpretation of ground-based OH rotational temperature measurements, because simultaneous observations of the vertical OH volume emission rate profile are usually not available for these measurements. OH emission altitude and vertically integrated emission rate time series with daily resolution for the OH(3-1) band and monthly resolution for the OH(6-2) band were analyzed using a standard multilinear regression approach allowing for seasonal variations, QBO-effects (Quasi-Biennial Oscillation), solar cycle (SC) variability and a linear long-term trend. The analysis focuses on low latitudes, where SCIAMACHY nighttime observations are available all year. The dominant sources of variability for both OH emission rate and altitude are the semi-annual and annual variations, with emission rate and altitude being highly anti-correlated. There is some evidence for a 11-year solar cycle signature in the vertically integrated emission rate and in the centroid emission altitude of both the OH(3-1) and OH(6-2) bands.

  2. Studies on the hepatosplenic volume and the accumulation rate of 99mTc Sn colloid in patients with liver cirrhosis by using single photon emission computed tomography

    International Nuclear Information System (INIS)

    Sato, Shizou; Mimura, Hisashi; Noda, Takuo; Hamazaki, Keisuke; Takakura, Norio; Tsuge, Hiroshi; Awai, Sachio; Hiraki, Yoshio; Orita, Kunzo

    1988-01-01

    The method using single photon emission computed tomography (SPECT) for measurement of the hepatosplenic volume and the accumulation rate of 99m Tc Sn colloid was studied, and applied to patients with liver cirrhosis. The hepatosplenic volume calculated by this method was well correlated with that by computed tomography (r = 0.938). The accumulation rate obtained by this method was almost equal to that by whole body scintigraphy. In liver cirrhosis (Child B and C group) the liver volume was atrophic and the splenic volume hypertrophic. The liver accumulation rate was decreased corresponding with the degree of liver cirrhosis, but the accumulation rate per volume was decreased in Child B and C. The splenic accumulation rate was increased in Child B and C, but the accumulation rate per volume was not significant between control group and liver cirrhosis. The measurement of the hepatosplenic volume and accumulation rate by SPECT is useful to evaluate the hepatosplenic function. (author)

  3. Observed Barium Emission Rates

    Science.gov (United States)

    Stenbaek-Nielsen, H. C.; Wescott, E. M.; Hallinan, T. J.

    1993-01-01

    The barium releases from the CRRES satellite have provided an opportunity for verifying theoretically calculated barium ion and neutral emission rates. Spectra of the five Caribbean releases in the summer of 1991 were taken with a spectrograph on board a U.S. Air Force jet aircraft. Because the line of sight release densities are not known, only relative rates could be obtained. The observed relative rates agree well with the theoretically calculated rates and, together with other observations, confirm the earlier detailed theoretical emission rates. The calculated emission rates can thus with good accuracy be used with photometric observations. It has been postulated that charge exchange between neutral barium and oxygen ions represents a significant source for ionization. If so. it should be associated with emissions at 4957.15 A and 5013.00 A, but these emissions were not detected.

  4. Storm/Quiet Ratio Comparisons Between TIMED/SABER NO (sup +)(v) Volume Emission Rates and Incoherent Scatter Radar Electron Densities at E-Region Altitudes

    Science.gov (United States)

    Fernandez, J. R.; Mertens, C. J.; Bilitza, D.; Xu, X.; Russell, J. M., III; Mlynczak, M. G.

    2009-01-01

    Broadband infrared limb emission at 4.3 microns is measured by the TIMED/SABER instrument. At night, these emission observations at E-region altitudes are used to derive the so called NO+(v) Volume Emission Rate (VER). NO+(v) VER can be derived by removing the background CO2(v3) 4.3 microns radiance contribution using SABER-based non-LTE radiation transfer models, and by performing a standard Abel inversion on the residual radiance. SABER observations show that NO+(v) VER is significantly enhanced during magnetic storms in accordance with increased ionization of the neutral atmosphere by auroral electron precipitation, followed by vibrational excitation of NO+ (i.e., NO+(v)) from fast exothermic ion-neutral reactions, and prompt infrared emission at 4.3 m. Due to charge neutrality, the NO+(v) VER enhancements are highly correlated with electron density enhancements, as observed for example by Incoherent Scatter Radar (ISR). In order to characterize the response of the storm-time E-region from both SABER and ISR measurements, a Storm/Quiet ratio (SQR) quantity is defined as a function of altitude. For SABER, the SQR is the ratio of the storm-to-quiet NO+(v) VER. SQR is the storm-to-quiet ratio of electron densities for ISR. In this work, we compare SABER and ISR SQR values between 100 to 120 km. Results indicate good agreement between these measurements. SQR values are intended to be used as a correction factor to be included in an empirical storm-time correction to the International Reference Ionosphere model at E-region altitudes.

  5. Arrhenius Rate: constant volume burn

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-06

    A constant volume burn occurs for an idealized initial state in which a large volume of reactants at rest is suddenly raised to a high temperature and begins to burn. Due to the uniform spatial state, there is no fluid motion and no heat conduction. This reduces the time evolu tion to an ODE for the reaction progress variable. With an Arrhenius reaction rate, two characteristics of thermal ignition are illustrated: induction time and thermal runaway. The Frank-Kamenetskii approximation then leads to a simple expression for the adiabatic induction time. For a first order reaction, the analytic solution is derived and used to illustrate the effect of varying the activation temperature; in particular, on the induction time. In general, the ODE can be solved numerically. This is used to illustrate the effect of varying the reaction order. We note that for a first order reaction, the time evolution of the reaction progress variable has an exponential tail. In contrast, for a reaction order less than one, the reaction completes in a nite time. The reaction order also affects the induction time.

  6. Tabulated Neutron Emission Rates for Plutonium Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Shores, Erik Frederick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-24

    This work tabulates neutron emission rates for 80 plutonium oxide samples as reported in the literature. Plutonium-­238 and plutonium-­239 oxides are included and such emission rates are useful for scaling tallies from Monte Carlo simulations and estimating dose rates for health physics applications.

  7. Flow rate measurement in a volume

    Energy Technology Data Exchange (ETDEWEB)

    Galvez, Cristhian

    2018-04-17

    A system for measuring flow rate within a volume includes one or more transmission devices that transmit one or more signals through fluid contained within the volume. The volume may be bounded, at least in part, by an outer structure and by an object at least partially contained within the outer structure. A transmission device located at a first location of the outer structure transmits a first signal to a second location of the outer structure. A second signal is transmitted through the fluid from the second location to a third location of the outer structure. The flow rate of the fluid within the volume may be determined based, at least in part, on the time of flight of both the first signal and the second signal.

  8. Partial Volume Effects correction in emission tomography

    International Nuclear Information System (INIS)

    Le Pogam, Adrien

    2010-01-01

    Partial Volume Effects (PVE) designates the blur commonly found in nuclear medicine images and this PhD work is dedicated to their correction with the objectives of qualitative and quantitative improvement of such images. PVE arise from the limited spatial resolution of functional imaging with either Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT). They can be defined as a signal loss in tissues of size similar to the Full Width at Half Maximum (FWHM) of the PSF of the imaging device. In addition, PVE induce activity cross contamination between adjacent structures with different tracer uptakes. This can lead to under or over estimation of the real activity of such analyzed regions. Various methodologies currently exist to compensate or even correct for PVE and they may be classified depending on their place in the processing chain: either before, during or after the image reconstruction process, as well as their dependency on co-registered anatomical images with higher spatial resolution, for instance Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). The voxel-based and post-reconstruction approach was chosen for this work to avoid regions of interest definition and dependency on proprietary reconstruction developed by each manufacturer, in order to improve the PVE correction. Two different contributions were carried out in this work: the first one is based on a multi-resolution methodology in the wavelet domain using the higher resolution details of a co-registered anatomical image associated to the functional dataset to correct. The second one is the improvement of iterative deconvolution based methodologies by using tools such as directional wavelets and curvelets extensions. These various developed approaches were applied and validated using synthetic, simulated and clinical images, for instance with neurology and oncology applications in mind. Finally, as currently available PET/CT scanners incorporate more

  9. Cervical Gross Tumor Volume Dose Predicts Local Control Using Magnetic Resonance Imaging/Diffusion-Weighted Imaging—Guided High-Dose-Rate and Positron Emission Tomography/Computed Tomography—Guided Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dyk, Pawel; Jiang, Naomi; Sun, Baozhou; DeWees, Todd A. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Fowler, Kathryn J.; Narra, Vamsi [Department of Diagnostic Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Garcia-Ramirez, Jose L.; Schwarz, Julie K. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Grigsby, Perry W., E-mail: pgrigsby@wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Gynecologic Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri (United States)

    2014-11-15

    Purpose: Magnetic resonance imaging/diffusion weighted-imaging (MRI/DWI)-guided high-dose-rate (HDR) brachytherapy and {sup 18}F-fluorodeoxyglucose (FDG) — positron emission tomography/computed tomography (PET/CT)-guided intensity modulated radiation therapy (IMRT) for the definitive treatment of cervical cancer is a novel treatment technique. The purpose of this study was to report our analysis of dose-volume parameters predicting gross tumor volume (GTV) control. Methods and Materials: We analyzed the records of 134 patients with International Federation of Gynecology and Obstetrics stages IB1-IVB cervical cancer treated with combined MRI-guided HDR and IMRT from July 2009 to July 2011. IMRT was targeted to the metabolic tumor volume and lymph nodes by use of FDG-PET/CT simulation. The GTV for each HDR fraction was delineated by use of T2-weighted or apparent diffusion coefficient maps from diffusion-weighted sequences. The D100, D90, and Dmean delivered to the GTV from HDR and IMRT were summed to EQD2. Results: One hundred twenty-five patients received all irradiation treatment as planned, and 9 did not complete treatment. All 134 patients are included in this analysis. Treatment failure in the cervix occurred in 24 patients (18.0%). Patients with cervix failures had a lower D100, D90, and Dmean than those who did not experience failure in the cervix. The respective doses to the GTV were 41, 58, and 136 Gy for failures compared with 67, 99, and 236 Gy for those who did not experience failure (P<.001). Probit analysis estimated the minimum D100, D90, and Dmean doses required for ≥90% local control to be 69, 98, and 260 Gy (P<.001). Conclusions: Total dose delivered to the GTV from combined MRI-guided HDR and PET/CT-guided IMRT is highly correlated with local tumor control. The findings can be directly applied in the clinic for dose adaptation to maximize local control.

  10. Volume growth rate of acoustic neurinomas

    International Nuclear Information System (INIS)

    Laasonen, E.M.; Troupp, H.

    1986-01-01

    Of 79 acoustic neurinomas seen between June 1980 and June 1984, at least two CT scans were available for each of 23 tumours (21 patients); the scans were performed at intervals of at least 6 months. The volume growth rate of the tumours was either moderate, with a volume doubling time ranging from 205 to 545 days, or slow, with a doubling time ranging from 1090 days to no observable growth. No single clinical, radiological or histological feature correlated with any type of growth rate. However, some conclusions were drawn. If a primary CT scan is negative, at least 1 year should elapse before it is worthwhile taking another scan, even though audiological findings suggest growth; after an apparently radical removal, at least 3 years should elapse before a check CT scan is worthwhile; and if a small acoustic neurinoma is diagnosed, but for some reason not operated upon, a second CT scan should be carried out 1 year later in order to reassess the case. (orig.)

  11. Measurement of liver volume by emission computed tomography

    International Nuclear Information System (INIS)

    Kan, M.K.; Hopkins, G.B.

    1979-01-01

    In 22 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography (ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-mean-square error of less than 6% between duplicate measurements in 15 individuals. The volume measurements were validated by the use of phantoms

  12. A carbon emissions reduction index: Integrating the volume and allocation of regional emissions

    International Nuclear Information System (INIS)

    Chen, Jiandong; Cheng, Shulei; Song, Malin; Wu, Yinyin

    2016-01-01

    Highlights: • We build a carbon emissions reduction index (CERI). • The aim is to quantify the pressure on policymakers to reduce emissions. • Scale-related effects and carbon emissions allocations are included in the CERI. • Different standards of carbon emissions allocations are also considered. • We decompose the Gini coefficient to evaluate the effects of three factors. - Abstract: Given the acceleration of global warming and rising greenhouse gas emissions, all countries are facing the harsh reality of the need to reduce carbon emissions. In this study, we propose an index to quantify the pressure faced by policymakers to reduce such emissions, termed the carbon emissions reduction index. This index allows us to observe the effect of carbon emissions volume on the pressure faced by policymakers and study the impact of optimizing interregional carbon emissions on reducing this pressure. In addition, we account for several carbon emissions standards in constructing the index. We conclude that the variation in the index is likely to be attributable to carbon emissions volume, regional ranking, and population (population can also be replaced by GDP, resource endowment, or other factors). In addition, based on empirical data on the world’s largest emitter of carbon dioxide (China), this study analyzes the evolution of pressure to reduce emissions on a country’s policymakers. The results show that the growing volume and unsuitable allocation of carbon emissions from 1997 to 2012 imposed increasing pressure on the Chinese government in this regard. In addition, reductions in carbon emissions volume and regional ranking are primary factors that impact pressure on policymakers.

  13. Airborne radioactive emission control technology. Volume II

    International Nuclear Information System (INIS)

    Skoski, L.; Berlin, R.; Corby, D.; Clancy, J.; Hoopes, G.

    1980-03-01

    This report reviews the current and future control technology for airborne emissions from a wide variety of industries/facilities, including uranium mining and milling, other nuclear fuel cycle facilities, other NRC-licensed and DOE facilities, fossil fuel facilities, selected metal and non-metal extraction industries, and others. Where specific radioactivity control technology is lacking, a description of any existing control technology is given. Future control technology is assessed in terms of improvements to equipment performance and process alterations. A catalogue of investigated research on advanced control technologies is presented

  14. Airborne radioactive emission control technology. Volume III

    International Nuclear Information System (INIS)

    Skoski, L.; Berlin, R.; Corby, D.; Clancy, J.; Hoopes, G.

    1980-03-01

    This report reviews the current and future control technology for airborne emissions from a wide variety of industries/facilities, including uranium mining and milling, other nuclear fuel cycle facilities, other NRC-licensed and DOE facilities, fossil fuel facilities, selected metal and non-metal extraction industries, and others. Where specific radioactivity control technology is lacking, a description of any existing control technology is given. Future control technology is assessed in terms of improvements to equipment performance and process alterations. A catalogue of investigated research on advanced control technologies is presented

  15. Airborne radioactive emission control technology. Volume I

    International Nuclear Information System (INIS)

    Skoski, L.; Berlin, R.; Corby, D.; Clancy, J.; Hoopes, G.

    1980-03-01

    This report reviews the current and future control technology for airborne emissions from a wide variety of industries/facilities, includimg uranium mining and milling, other nuclear fuel cycle facilities, other NRC-licensed and DOE facilities, fossil fuel facilities, selected metal and non-metal extraction industries, and others. Where specific radioactivity control technology is lacking a description of any existing control technology is given. Future control technology is assessed in terms of improvements to equipment performance and process alterations. A catalogue of investigated research on advanced control technologies is presented

  16. Design of a volume-imaging positron emission tomograph

    International Nuclear Information System (INIS)

    Harrop, R.; Rogers, J.G.; Coombes, G.H.; Wilkinson, N.A.; Pate, B.D.; Morrison, K.S.; Stazyk, M.; Dykstra, C.J.; Barney, J.S.; Atkins, M.S.; Doherty, P.W.; Saylor, D.P.

    1988-11-01

    Progress is reported in several areas of design of a positron volume imaging tomograph. As a means of increasing the volume imaged and the detector packing fraction, a lens system of detector light coupling is considered. A prototype layered scintillator detector demonstrates improved spatial resolution due to a unique Compton rejection capability. The conceptual design of a new mechanism for measuring scattered radiation during emission scans has been tested by Monte Carlo simulation. The problem of how to use effectively the resulting sampled scattered radiation projections is presented and discussed

  17. Does Exchange Rate Volatility Affect Korea's Seaborne Import Volume?

    Directory of Open Access Journals (Sweden)

    Chang Beom Kim

    2017-03-01

    Full Text Available This study used monthly data from 2000 to 2015 to analyze the effects of USD/KRW exchange rate volatility on seaborne import volume in Korea. The results of an autoregressive distributed lag (ARDL analysis indicate that USD/KRW exchange rate volatility has a statistically significant negative influence on Korea's seaborne import volume. Moreover, the results of a vector error correction model (VECM analysis found that the USD/KRW exchange rate volatility exhibited short-term unidirectional causality on import volume and real income, and confirmed bidirectional causality between the real effective exchange rate and exchange rate volatility.

  18. Supernova rates, galaxy emission, and Hubble type

    International Nuclear Information System (INIS)

    Van Den Bergh, S.

    1991-01-01

    Supernova discovery frequency is found to correlate with emission-line (H-alpha + forbidden N II line) equivalent width, except for the most active galaxies in which some supernovae might be hidden by dust. SNII occur preferentially in active galaxies with emission-line EW not less than 20 A, whereas SNIa favor less active galaxies with EW less than 20 A. The intrinsic frequency of supernovae is found to be an order of magnitude higher in Sc galaxies than it is in early type spirals. The relatively high frequency of SNIa in late-type galaxies suggests that not all such objects have old progenitors. 13 refs

  19. Chemical emission rates from personal computers

    DEFF Research Database (Denmark)

    Nakagawa, T.; Wargocki, Pawel; Tanabe, S.

    2003-01-01

    Chemical emission measurements from different brands of personal computers (PCs) were conducted in a 1 m3 glass chamber. Eight PCs were tested individually. Each consisted of the same brand of PC tower and one of the 4 different brands of PC monitors. Within each brand both cathode-ray tube (CRT...

  20. Research on Acoustic Emission and Electromagnetic Emission Characteristics of Rock Fragmentation at Different Loading Rates

    Directory of Open Access Journals (Sweden)

    Fujun Zhao

    2018-01-01

    Full Text Available The relationships among the generation of acoustic emission, electromagnetic emission, and the fracture stress of rock grain are investigated, which are based on the mechanism of acoustic emission and electromagnetic emission produced in the process of indenting rock. Based on the relationships, the influence of loading rate on the characteristics of acoustic emission and electromagnetic emission of rock fragmentation is further discussed. Experiment on rock braking was carried out with three loading rates of 0.001 mm/s, 0.01 mm/s, and 0.1 mm/s. The results show that the phenomenon of acoustic emission and electromagnetic emission is produced during the process of loading and breaking rock. The wave forms of the two signals and the curve of the cutter indenting load show jumping characteristics. Both curves have good agreement with each other. With the increase of loading rate, the acoustic emission and electromagnetic emission signals are enhanced. Through analysis, it is found that the peak count rate, the energy rate of acoustic emission, the peak intensity, the number of pulses of the electromagnetic emission, and the loading rate have a positive correlation with each other. The experimental results agree with the theoretical analysis. The proposed studies can lead to an in-depth understanding of the rock fragmentation mechanism and help to prevent rock dynamic disasters.

  1. Heart Rate and Increased Intravascular Volume

    Czech Academy of Sciences Publication Activity Database

    Souček, M.; Kára, T.; Jurák, Pavel; Halámek, Josef; Špinarová, L.; Meluzín, J.; Toman, J.; Řiháček, I.; Šumbera, J.; Fráňa, P.

    2003-01-01

    Roč. 52, - (2003), s. 137 - 140 ISSN 0862-8408 R&D Projects: GA ČR GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : kidneys * heart rate * atrial mechanisms Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 0.939, year: 2003

  2. Emission of formaldehyde by particleboard : effect of ventilation rate and loading on air-contamination levels

    Science.gov (United States)

    George E. Myers; Muneo Nagaoka

    1981-01-01

    Dynamic tests for determining the formaldehyde emission behavior of UF-bonded boards involve the measurement of formaldehyde concentration in the air within a vessel which contains a specified board loading L (m2 of board area per m3 of vessel free volume) and is being ventilated at a specified air exchange rate N (hr.-1). Such tests constitute a primary...

  3. Gaussian model for emission rate measurement of heated plumes using hyperspectral data

    Science.gov (United States)

    Grauer, Samuel J.; Conrad, Bradley M.; Miguel, Rodrigo B.; Daun, Kyle J.

    2018-02-01

    This paper presents a novel model for measuring the emission rate of a heated gas plume using hyperspectral data from an FTIR imaging spectrometer. The radiative transfer equation (RTE) is used to relate the spectral intensity of a pixel to presumed Gaussian distributions of volume fraction and temperature within the plume, along a line-of-sight that corresponds to the pixel, whereas previous techniques exclusively presume uniform distributions for these parameters. Estimates of volume fraction and temperature are converted to a column density by integrating the local molecular density along each path. Image correlation velocimetry is then employed on raw spectral intensity images to estimate the volume-weighted normal velocity at each pixel. Finally, integrating the product of velocity and column density along a control surface yields an estimate of the instantaneous emission rate. For validation, emission rate estimates were derived from synthetic hyperspectral images of a heated methane plume, generated using data from a large-eddy simulation. Calculating the RTE with Gaussian distributions of volume fraction and temperature, instead of uniform distributions, improved the accuracy of column density measurement by 14%. Moreover, the mean methane emission rate measured using our approach was within 4% of the ground truth. These results support the use of Gaussian distributions of thermodynamic properties in calculation of the RTE for optical gas diagnostics.

  4. The order and volume fill rates in inventory control systems

    DEFF Research Database (Denmark)

    Thorstenson, Anders; Larsen, Christian

    2011-01-01

    This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total quantities the order fill rate would be the preferred service level m...

  5. The order and volume fill rates in inventory control systems

    DEFF Research Database (Denmark)

    Thorstenson, Anders; Larsen, Christian

    2011-01-01

    This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total quantities the order fill rate would be the preferred service level...... measure. The main result shows how the order and volume fill rates are related in magnitude. Earlier results derived for a single-item, single-stage, continuous review inventory system with backordering and constant lead times controlled by a base-stock policy are extended in different directions...

  6. Modeling emission rates and exposures from outdoor cooking

    Science.gov (United States)

    Edwards, Rufus; Princevac, Marko; Weltman, Robert; Ghasemian, Masoud; Arora, Narendra K.; Bond, Tami

    2017-09-01

    Approximately 3 billion individuals rely on solid fuels for cooking globally. For a large portion of these - an estimated 533 million - cooking is outdoors, where emissions from cookstoves pose a health risk to both cooks and other household and village members. Models that estimate emissions rates from stoves in indoor environments that would meet WHO air quality guidelines (AQG), explicitly don't account for outdoor cooking. The objectives of this paper are to link health based exposure guidelines with emissions from outdoor cookstoves, using a Monte Carlo simulation of cooking times from Haryana India coupled with inverse Gaussian dispersion models. Mean emission rates for outdoor cooking that would result in incremental increases in personal exposure equivalent to the WHO AQG during a 24-h period were 126 ± 13 mg/min for cooking while squatting and 99 ± 10 mg/min while standing. Emission rates modeled for outdoor cooking are substantially higher than emission rates for indoor cooking to meet AQG, because the models estimate impact of emissions on personal exposure concentrations rather than microenvironment concentrations, and because the smoke disperses more readily outdoors compared to indoor environments. As a result, many more stoves including the best performing solid-fuel biomass stoves would meet AQG when cooking outdoors, but may also result in substantial localized neighborhood pollution depending on housing density. Inclusion of the neighborhood impact of pollution should be addressed more formally both in guidelines on emissions rates from stoves that would be protective of health, and also in wider health impact evaluation efforts and burden of disease estimates. Emissions guidelines should better represent the different contexts in which stoves are being used, especially because in these contexts the best performing solid fuel stoves have the potential to provide significant benefits.

  7. Thermal history regulates methylbutenol basal emission rate in Pinus ponderosa.

    Science.gov (United States)

    Gray, Dennis W; Goldstein, Allen H; Lerdau, Manuel T

    2006-07-01

    Methylbutenol (MBO) is a 5-carbon alcohol that is emitted by many pines in western North America, which may have important impacts on the tropospheric chemistry of this region. In this study, we document seasonal changes in basal MBO emission rates and test several models predicting these changes based on thermal history. These models represent extensions of the ISO G93 model that add a correction factor C(basal), allowing MBO basal emission rates to change as a function of thermal history. These models also allow the calculation of a new emission parameter E(standard30), which represents the inherent capacity of a plant to produce MBO, independent of current or past environmental conditions. Most single-component models exhibited large departures in early and late season, and predicted day-to-day changes in basal emission rate with temporal offsets of up to 3 d relative to measured basal emission rates. Adding a second variable describing thermal history at a longer time scale improved early and late season model performance while retaining the day-to-day performance of the parent single-component model. Out of the models tested, the T(amb),T(max7) model exhibited the best combination of day-to-day and seasonal predictions of basal MBO emission rates.

  8. Cooperative spontaneous emission from volume sources in layered media

    International Nuclear Information System (INIS)

    Nichelatti, E.

    2009-01-01

    The classical theory of radiation from a dipole located inside a microcavity is extended to the case of a volume source placed inside a layered medium. Cooperation phenomena that can take place in the spontaneous emission process are taken into account with an approach based on the theory of spatial coherence. Three cases are considered: noncooperation, long-range cooperation, and short-range cooperation. In all these cases, the expressions found for the out coupled power are analytical. As an application of the theory, an Alq 3 -based organic light emitting diode is analyzed. The optical properties of the device are evaluated and compared for two different types of cathode, one consisting of an Al layer, the other one consisting of an Al/LiF bi-layer. The results found show that the ultra-thin LiF layer significantly improves extraction efficiency [it

  9. The order and volume fill rates in inventory control systems

    DEFF Research Database (Denmark)

    Thorstenson, Anders; Larsen, Christian

    2014-01-01

    This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total demanded quantity the order fill rate would be the preferred service...... level measure. The main result shows how the order and volume fill rates are related in magnitude. Earlier results derived for a single-item, single-stage, continuous review inventory system with backordering and constant lead times controlled by a base-stock policy are extended in different directions...... extensions consider more general inventory control review policies with backordering, as well as some relations between service measures. A particularly important result in the paper concerns an alternative service measure, the customer order fill rate, and shows how this measure always exceeds the other two...

  10. Estimating marginal CO2 emissions rates for national electricity systems

    International Nuclear Information System (INIS)

    Hawkes, A.D.

    2010-01-01

    The carbon dioxide (CO 2 ) emissions reduction afforded by a demand-side intervention in the electricity system is typically assessed by means of an assumed grid emissions rate, which measures the CO 2 intensity of electricity not used as a result of the intervention. This emissions rate is called the 'marginal emissions factor' (MEF). Accurate estimation of MEFs is crucial for performance assessment because their application leads to decisions regarding the relative merits of CO 2 reduction strategies. This article contributes to formulating the principles by which MEFs are estimated, highlighting the strengths and weaknesses in existing approaches, and presenting an alternative based on the observed behaviour of power stations. The case of Great Britain is considered, demonstrating an MEF of 0.69 kgCO 2 /kW h for 2002-2009, with error bars at +/-10%. This value could reduce to 0.6 kgCO 2 /kW h over the next decade under planned changes to the underlying generation mix, and could further reduce to approximately 0.51 kgCO 2 /kW h before 2025 if all power stations commissioned pre-1970 are replaced by their modern counterparts. Given that these rates are higher than commonly applied system-average or assumed 'long term marginal' emissions rates, it is concluded that maintenance of an improved understanding of MEFs is valuable to better inform policy decisions.

  11. Emission trading in Europe with an exchange rate

    International Nuclear Information System (INIS)

    Klassen, G.A.J.; Amann, M.; Foersund, F.R.

    1994-01-01

    The analytical and empirical properties of a new method for emission trading according to a fixed exchange rate are explored. The exchange rate is based on the ratios of the marginal costs of abatement in the optimal solution in order to account for the impact of the location of emission sources on the deposition. It is shown that, generally, this system will not achieve the optimal solution and does not guarantee that environmental deposition constraints are not violated, although total abatement costs are always reduced. A routine was developed to mimic trading as a bilateral, sequential process, subject to an exchange rate. Use has been made of an adapted version of the optimization module in the RAINS (REgional Acidification INformation and Simulation) model. In the example used, results for SO 2 emissions in Europe show that, starting from a uniform reduction, exchange-rate trading achieves higher cost savings than one-to-one trading, without achieving the cost minimum. Sulfur deposition targets are not violated since the initial emission allocation overfulfilled targets at many places. The results are sensitive to: pre-trade emission levels, the transaction costs, the availability of information on potential cost savings and assumptions made on the behavior of trading partners. 6 figs., 3 tabs., 28 refs

  12. A global gas flaring black carbon emission rate dataset from 1994 to 2012

    Science.gov (United States)

    Huang, Kan; Fu, Joshua S.

    2016-11-01

    Global flaring of associated petroleum gas is a potential emission source of particulate matters (PM) and could be notable in some specific regions that are in urgent need of mitigation. PM emitted from gas flaring is mainly in the form of black carbon (BC), which is a strong short-lived climate forcer. However, BC from gas flaring has been neglected in most global/regional emission inventories and is rarely considered in climate modeling. Here we present a global gas flaring BC emission rate dataset for the period 1994-2012 in a machine-readable format. We develop a region-dependent gas flaring BC emission factor database based on the chemical compositions of associated petroleum gas at various oil fields. Gas flaring BC emission rates are estimated using this emission factor database and flaring volumes retrieved from satellite imagery. Evaluation using a chemical transport model suggests that consideration of gas flaring emissions can improve model performance. This dataset will benefit and inform a broad range of research topics, e.g., carbon budget, air quality/climate modeling, and environmental/human exposure.

  13. Methyl chavicol: characterization of its biogenic emission rate

    NARCIS (Netherlands)

    Bouvier-Brown, N.C.; Goldstein, A.H.; Worton, D.R.; Matross, D.M.; Gilman, J.B.; Kuster, W.C.; Welsh-Bon, D.; Warneke, C.; de Gouw, J.A.; Cahill, M.J.; Holzinger, R.

    2009-01-01

    We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California.

  14. Lidar method to estimate emission rates from extended sources

    Science.gov (United States)

    Currently, point measurements, often combined with models, are the primary means by which atmospheric emission rates are estimated from extended sources. However, these methods often fall short in their spatial and temporal resolution and accuracy. In recent years, lidar has emerged as a suitable to...

  15. Sensory ratings of emissions from nontraditional building materials

    DEFF Research Database (Denmark)

    Krejcirikova, Barbora; Kolarik, Jakub; Peuhkuri, Ruut

    2016-01-01

    Twenty-five subjects assessed the emissions from building materials: linoleum, cement mortar with and without fly ash, gypsum board and tiles with air cleaning properties and natural organic sheep wool. The ratings were made at different material loadings and in combinations with linoleum....... The results showed that except for natural organic product, increasing loading and combining materials with linoleum increased intensity of odor....

  16. Inner volume leakage during integrated leakage rate testing

    International Nuclear Information System (INIS)

    Glover, J.P.

    1987-01-01

    During an integrated leak rate test (ILRT), the containment structure is maintained at test pressure with most penetrations isolated. Since penetrations typically employ dual isolation, the possibility exists for the inner isolation to leak while the outer holds. In this case, the ILRT instrumentation system would indicate containment out-leakage when, in fact, only the inner volume between closures is being pressurized. The problem is compounded because this false leakage is not readily observable outside of containment by standard leak inspection techniques. The inner volume leakage eventually subsides after the affected volumes reach test pressure. Depending on the magnitude of leakage and the size of the volumes, equalization could occur prior to the end of the pretest stabilization period, or significant false leakages may persist throughout the entire test. Two simple analyses were performed to quantify the effects of inside volume leakages. First, a lower bound for the equalization time was found. A second analysis was performed to find an approximate upper bound for the stabilization time. The results of both analyses are shown

  17. Surgical volume and conversion rate in laparoscopic hysterectomy: does volume matter? A multicenter retrospective cohort study.

    Science.gov (United States)

    Keurentjes, José H M; Briët, Justine M; de Bock, Geertruida H; Mourits, Marian J E

    2018-02-01

    A multicenter, retrospective, cohort study was conducted in the Netherlands. The aim was to evaluate whether surgical volume of laparoscopic hysterectomies (LHs) performed by proven skilled gynecologists had an impact on the conversion rate from laparoscopy to laparotomy. In 14 hospitals, all LHs performed by 19 proven skilled gynecologists between 2007 and 2010 were included in the analysis. Surgical volume, conversion rate and type of conversion (reactive or strategic) were retrospectively assessed. To estimate the impact of surgical volume on the conversion rate, logistic regressions were performed. These regressions were adjusted for patient's age, Body Mass Index (BMI), ASA classification, previous abdominal surgery and the indication (malignant versus benign) for the LH. During the study period, 19 proven skilled gynecologists performed a total of 1051 LHs. Forty percent of the gynecologists performed over 20 LHs per year (median 17.3, range 5.4-49.5). Conversion to laparotomy occurred in 5.0% of all LHs (53 of 1051); 38 (3.6%) were strategic and 15 (1.4%) were reactive conversions. Performing over 20 LHs per year was significantly associated with a lower overall conversion rate (OR adjusted 0.43, 95% CI 0.24-0.77), a lower strategic conversion rate (OR adjusted 0.32, 95% CI 0.16-0.65), but not with a lower reactive conversion rate (OR adjusted 0.96, 95% CI 0.33-2.79). A higher annual surgical volume of LHs by proven skilled gynecologists is inversely related to the conversion rate to laparotomy, and results in a lower strategic conversion rate.

  18. FURTHER STUDIES ON THE VARIATION OF SPRAY DEPOSITS IN VINEYARDS WITH AIRFLOW RATE AND VOLUME RATE

    Directory of Open Access Journals (Sweden)

    Emanuele Cerruto

    2007-03-01

    Full Text Available The present research, continuing that reported in [2], deals with the spray application subject, so to investigate as volume rate and airflow rate, forward speed being equal, affect the foliar deposition in an espalier vineyard. Experimental trials were carried out by means of an air assisted towed sprayer, equipped with “Albuz ATR” nozzles. To take into account the influence of the development of the trees, the field trials were replicated in two phenological stages with an interval of about one month: “Inflorescences fully developed” (stage 1 and “Beginning of berry touch” (stage 2. A full factorial experiment was carried out for each growth stage, with two airflow rates (3.9 and 7.5 m3/s, three volume rates (103, 216, and 276 L/ha in the first growth stage and 154, 330 and 432 L/ha in the second growth stage, and four replicates, arranged according to a randomised complete block design. Working pressure (1.2 MPa and forward speed (1.4 m/s were kept unchanged for all the trials. The foliar deposition was measured by means of a spectrophotometric technique. The leaves were sampled on two depth layers and two or three heights, according to the trees’ development. The results showed that volume rate did not significantly influence the mean foliar deposition in both the two growth stages, while the highest deposits were obtained with the lowest airflow rate. The airflow rate × volume rate interaction, though not statistically significant, showed that low volume rates together with high airflow rates, result in a noticeable reduction in foliar deposition (29% with respect the grand mean, due to an increase of the spry drift, especially at the first growth stage, when the foliar development is little. These second tests, unlike those described in [2], did not show any positive influence of the airflow rate on the foliar deposition in the inner part of the canopy, so further investigations could be necessary to better understand the

  19. Hekla Volcano, Iceland, in the 20th Century: Lava Volumes, Production Rates, and Effusion Rates

    Science.gov (United States)

    Pedersen, G. B. M.; Belart, J. M. C.; Magnússon, E.; Vilmundardóttir, O. K.; Kizel, F.; Sigurmundsson, F. S.; Gísladóttir, G.; Benediktsson, J. A.

    2018-02-01

    Lava flow thicknesses, volumes, and effusion rates provide essential information for understanding the behavior of eruptions and their associated deformation signals. Preeruption and posteruption elevation models were generated from historical stereo photographs to produce the lava flow thickness maps for the last five eruptions at Hekla volcano, Iceland. These results provide precise estimation of lava bulk volumes: V1947-1948 = 0.742 ± 0.138 km3, V1970 = 0.205 ± 0.012 km3, V1980-1981 = 0.169 ± 0.016 km3, V1991 = 0.241 ± 0.019 km3, and V2000 = 0.095 ± 0.005 km3 and reveal variable production rate through the 20th century. These new volumes improve the linear correlation between erupted volume and coeruption tilt change, indicating that tilt may be used to determine eruption volume. During eruptions the active vents migrate 325-480 m downhill, suggesting rough excess pressures of 8-12 MPa and that the gradient of this excess pressure increases from 0.4 to 11 Pa s-1 during the 20th century. We suggest that this is related to increased resistance along the eruptive conduit.

  20. Seasonal variations in VOC emission rates from gorse (Ulex europaeus)

    Science.gov (United States)

    Boissard, C.; Cao, X.-L.; Juan, C.-Y.; Hewitt, C. N.; Gallagher, M.

    Seasonal variations of biogenic volatile organic compound (VOC) emission rates and standardised emission factors from gorse (Ulex europaeus) have been measured at two sites in the United Kingdom, from October 1994 to September 1995, within temperature and PAR conditions ranging from 3 to 34°C and 10-1300 μmol m-2 s-1, respectively. Isoprene was the dominant emitted compound with a relative composition fluctuating from 7% of the total VOC (winter) to 97% (late summer). The monoterpenes α-pinene, camphene, sabinene, β-pinene, myrcene, limonene, trans-ocimene and γ-terpinene were also emitted, with α-pinene being the dominant monoterpene during most the year. Trans-ocimene represented 33-66% of the total monoterpene during the hottest months from June to September. VOC emissions were found to be accurately predicted using existing algorithms. Standard (normalised) emission factors of VOCs from gorse were calculated using experimental parameters measured during the experiment and found to fluctuate with season, from 13.3±2.1 to 0.1±0.1 μg C (g dwt)-1 h-1 in August 1995 and January 1995, respectively, for isoprene, and from 2.5±0.2 to 0.4±0.2 μg C (g dwt)-1 h-1 in July and November 1995, respectively, for total monoterpenes. No simple clear relation was found to allow prediction of these seasonal variations with respect to temperature and light intensity. The effects of using inappropriate algorithms to derive VOC fluxes from gorse were assessed for isoprene and monoterpenes. Although on an annual basis the discrepancies are not significant, monthly estimation of isoprene were found to be overestimated by more than a factor of 50 during wintertime when the seasonality of emission factors is not considered.

  1. Real-world fuel use and gaseous emission rates for flex fuel vehicles operated on E85 versus gasoline.

    Science.gov (United States)

    Delavarrafiee, Maryam; Frey, H Christopher

    2018-03-01

    Flex fuel vehicles (FFVs) typically operate on gasoline or E85, an 85%/15% volume blend of ethanol and gasoline. Differences in FFV fuel use and tailpipe emission rates are quantified for E85 versus gasoline based on real-world measurements of five FFVs with a portable emissions measurement system (PEMS), supplemented chassis dynamometer data, and estimates from the Motor Vehicle Emission Simulator (MOVES) model. Because of inter-vehicle variability, an individual FFV may have higher nitrogen oxide (NO x ) or carbon monoxide (CO) emission rates on E85 versus gasoline, even though average rates are lower. Based on PEMS data, the comparison of tailpipe emission rates for E85 versus gasoline is sensitive to vehicle-specific power (VSP). For example, although CO emission rates are lower for all VSP modes, they are proportionally lowest at higher VSP. Driving cycles with high power demand are more advantageous with respect to CO emissions, but less advantageous for NO x . Chassis dynamometer data are available for 121 FFVs at 50,000 useful life miles. Based on the dynamometer data, the average difference in tailpipe emissions for E85 versus gasoline is -23% for NO x , -30% for CO, and no significant difference for hydrocarbons (HC). To account for both the fuel cycle and tailpipe emissions from the vehicle, a life cycle inventory was conducted. Although tailpipe NO x emissions are lower for E85 versus gasoline for FFVs and thus benefit areas where the vehicles operate, the life cycle NO x emissions are higher because the NO x emissions generated during fuel production are higher. The fuel production emissions take place typically in rural areas. Although there are not significant differences in the total HC emissions, there are differences in HC speciation. The net effect of lower tailpipe NO x emissions and differences in HC speciation on ozone formation should be further evaluated. Reported comparisons of flex fuel vehicle (FFV) tailpipe emission rates for E85 versus

  2. Control of Atmospheric Emissions in the Wood Pulping Industry, Volume 3.

    Science.gov (United States)

    Hendrickson, E. R.; And Others

    Volume 3 contains chapters 9 through 13 of the final report on the control of atmospheric emissions in the wood pulping industry. These chapters deal with the following topics: sampling and analytical techniques; on-going research related to reduction of emissions; research and development recommendations; current industry investment and operating…

  3. METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 15: GAS-ASSISTED GLYCOL PUMPS

    Science.gov (United States)

    The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

  4. METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 13: CHEMICAL INJECTION PUMPS

    Science.gov (United States)

    The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

  5. METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 1: EXECUTIVE SUMMARY

    Science.gov (United States)

    The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

  6. 40 CFR 75.83 - Calculation of Hg mass emissions and heat input rate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Calculation of Hg mass emissions and... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Hg Mass Emission Provisions § 75.83 Calculation of Hg mass emissions and heat input rate. The owner or operator shall calculate Hg mass emissions...

  7. Study of brittle crack jump rate using acoustic emission method

    International Nuclear Information System (INIS)

    Yasnij, P.V.; Pokrovskij, V.V.; Strizhalo, V.A.; Dobrovol'skij, Yu.V.

    1987-01-01

    A new peocedure is elaborated to detect brittle jumps of small length (0.1...5mm) occuring both inside the specimen and along the crack front under static and cyclic loading using the phenomena of acoustic emission (AE). Recording of the crack start and stop moments with an AE sensor as well as evaluation of the brittle crack jump length by the after-failure specimen fracture make it possible to find the mean crack propagation rate. Experimental dependences are obtained for the crack propagation rate with a brittle crack jump in steel 15Kh2MFA (σ B =1157 MPa, σ 0.2 =100 MPa) at 293 K and under cyclic loading as a function of the jump length and also as a function of the critical stress intensity factor K jc i corresponding to the crack jump

  8. Drivers of CO2 Emission Rates from Dead Wood Logs of 13 Tree Species in the Initial Decomposition Phase

    Directory of Open Access Journals (Sweden)

    Tiemo Kahl

    2015-07-01

    Full Text Available Large dead wood is an important structural component of forest ecosystems and a main component of forest carbon cycles. CO2 emissions from dead wood can be used as a proxy for actual decomposition rates. The main drivers of CO2 emission rates for dead wood of temperate European tree species are largely unknown. We applied a novel, closed chamber measurement technique to 360 dead wood logs of 13 important tree species in three regions in Germany. We found that tree species identity was with 71% independent contribution to the model (R2 = 0.62 the most important driver of volume-based CO2 emission rates, with angiosperms having on average higher rates than conifers. Wood temperature and fungal species richness had a positive effect on CO2 emission rates, whereas wood density had a negative effect. This is the first time that positive fungal species richness—wood decomposition relationship in temperate forests was shown. Certain fungal species were associated with high or low CO2 emission rates. In addition, as indicated by separate models for each tree species, forest management intensity, study region, and the water content as well as C and N concentration of dead wood influenced CO2 emission rates.

  9. Tc-99m-DMSA renal uptake rate and renal volume of elderly persons

    International Nuclear Information System (INIS)

    Ohishi, Yukihiko; Machida, Toyohei; Kido, Akira

    1987-01-01

    Renal function of erderly persons was evaluated by the radionuclide renal function test based on the renal uptake rate and the renal volume determined by Tc-99m-DMSA transectional tomographic images using single photon emission computed tomography (SPECT). Forty-three erderly cases (13 healthy persons and 30 patients with various types of renal disorders) aged between 60 and 87 on an average of 70 were studied and compared with results obtained from 20 healthy adults (18 - 45 years old). Renal volume was calculated from the summation of voxels in the region districted by equi-count threshold level (percentage to maximum count) on each section of the SPECT image. Attenuation correction was made by GE-STAR protocol utilizing Sorrenson's precorrection method. The renal uptake rate was expressed as a percentage of the total radioactivity detected within the renal volume, against an amount of dose injected. In the 26 kidneys of 13 healthy elderly persons, Tc-99m-DMSA renal uptake was 23 ± 5 %, which was significantly lower (p < 0.01) than that of healthy adults being 27 ± 2 %. A correlation coefficient between renal volume and uptake of 79 kidneys of 43 elderly persons was 0.5081 (p < 0.01). Creatinine clearance (Ccr) was better correlated with the total renal uptake (r = 0.6471, p < 0.01) than with the total renal volume (r = 0.3592, p < 0.01). This method is considered to be useful for clinical purpose as a test of renal function for elderly persons since it requires neither blood nor urine samples. (author)

  10. Proton upset rate prediction: a new sensitive volume concept definition

    International Nuclear Information System (INIS)

    Inguimbert, Christophe

    1999-01-01

    We present a model for predicting proton induced single event upset rate. The approach uses heavy ion cross section experimental data combined with nuclear reaction calculations in order to determine the proton upset cross section. The p+Si nuclear reaction as well as the Si(p, p)Si Coulombic scattering are described. The upset rate calculation depends on the energy deposited available in the charge collection region (sensitive region). This region is treated as a rectangular parallelepiped of thickness d at depth h. The sensitive thickness d is used as an input parameter in our model we have developed an original method to probe the sensitive region to evaluate d with reasonable accuracy d. We use short range ions and we propose a new mathematical analysis of these experimental data to determine h and d. This method consists in de-convoluting the heavy ion upset cross section σ_S_E_U(r) by the LET function of the incident ion LET(r) (r is the range of the incident ion). Our results are in relatively good agreement with other models. The accuracy of the method allows us to discuss the validity of the sensitive volume concept. Furthermore, we extrapolate an internal gain factor α that permit to take into account the charge collection mechanisms. α and d serve for quick and reasonably accurate prediction of proton induced SEU cross section in microelectronic devices. (author) [fr

  11. Estimating permissible /sup 129/I-emission rates

    Energy Technology Data Exchange (ETDEWEB)

    Huebschmann, W G

    1976-06-01

    A mathematical method of iodine release limitation is presented which, in assessing the radiological effectiveness of /sup 129/I, takes advantage of the fact that the chemical behaviour of /sup 129/I resembles that of /sup 131/I and relies on the already extensive knowledge of the chemical and biological behaviour of /sup 131/I. If this method is used for calculating permissible /sup 129/I emission rates it is stated that no unnecessary restrictions need be imposed on a fuel reprocessing plant and that the grazing season for the pasture-cow-milk pathway can be taken into account. The concept is currently in use at the Karlsruhe Nuclear Research Center and seems to be appropriate for licensing of nuclear fuel reprocessing plants.

  12. VOC emission rates over London and South East England obtained by airborne eddy covariance.

    Science.gov (United States)

    Vaughan, Adam R; Lee, James D; Shaw, Marvin D; Misztal, Pawel K; Metzger, Stefan; Vieno, Massimo; Davison, Brian; Karl, Thomas G; Carpenter, Lucy J; Lewis, Alastair C; Purvis, Ruth M; Goldstein, Allen H; Hewitt, C Nicholas

    2017-08-24

    Volatile organic compounds (VOCs) originate from a variety of sources, and play an intrinsic role in influencing air quality. Some VOCs, including benzene, are carcinogens and so directly affect human health, while others, such as isoprene, are very reactive in the atmosphere and play an important role in the formation of secondary pollutants such as ozone and particles. Here we report spatially-resolved measurements of the surface-to-atmosphere fluxes of VOCs across London and SE England made in 2013 and 2014. High-frequency 3-D wind velocities and VOC volume mixing ratios (made by proton transfer reaction - mass spectrometry) were obtained from a low-flying aircraft and used to calculate fluxes using the technique of eddy covariance. A footprint model was then used to quantify the flux contribution from the ground surface at spatial resolution of 100 m, averaged to 1 km. Measured fluxes of benzene over Greater London showed positive agreement with the UK's National Atmospheric Emissions Inventory, with the highest fluxes originating from central London. Comparison of MTBE and toluene fluxes suggest that petroleum evaporation is an important emission source of toluene in central London. Outside London, increased isoprene emissions were observed over wooded areas, at rates greater than those predicted by a UK regional application of the European Monitoring and Evaluation Programme model (EMEP4UK). This work demonstrates the applicability of the airborne eddy covariance method to the determination of anthropogenic and biogenic VOC fluxes and the possibility of validating emission inventories through measurements.

  13. Towards high-resolution positron emission tomography for small volumes

    International Nuclear Information System (INIS)

    McKee, B.T.A.

    1982-01-01

    Some arguments are made regarding the medical usefulness of high spatial resolution in positron imaging, even if limited to small imaged volumes. Then the intrinsic limitations to spatial resolution in positron imaging are discussed. The project to build a small-volume, high resolution animal research prototype (SHARP) positron imaging system is described. The components of the system, particularly the detectors, are presented and brief mention is made of data acquisition and image reconstruction methods. Finally, some preliminary imaging results are presented; a pair of isolated point sources and 18 F in the bones of a rabbit. Although the detector system is not fully completed, these first results indicate that the goals of high sensitivity and high resolution (4 mm) have been realized. (Auth.)

  14. Studies of left ventricular volume estimation from single photon emission computed tomography

    International Nuclear Information System (INIS)

    Hiraki, Yoshio; Shimizu, Mitsuharu; Joja, Ikuo; Aono, Kaname; Yanagi, Hidekiyo; Indo, Haruaki; Seno, Yoshimasa; Teramoto, Shigeru; Nagaya, Isao.

    1988-01-01

    We studied the comparative accuracy of 99m Tc cardiac blood pool Single Photon Emission Computed Tomography (SPECT) for the measurement of left ventricular volume in 20 patients undergoing SPECT and single plane contrast left ventriculography (LVG). Left ventricular volume was calculated based on the total number of voxels in left ventricle. End-diastolic left ventricular volume (EDV) and end-systolic left ventricular volume (ESV) calculated from SPECT were compared with those from LVG. SPECT volume values showed a high degree of correlation with those by LVG (r = 0.923 for EDV, r = 0.903 for ESV). We appreciated the usefulness and accuracy of SPECT in measuring left ventricular volume because of its three-dimensional information. (author)

  15. [Estimation of VOC emission from forests in China based on the volume of tree species].

    Science.gov (United States)

    Zhang, Gang-feng; Xie, Shao-dong

    2009-10-15

    Applying the volume data of dominant trees from statistics on the national forest resources, volatile organic compounds (VOC) emissions of each main tree species in China were estimated based on the light-temperature model put forward by Guenther. China's VOC emission inventory for forest was established, and the space-time and age-class distributions of VOC emission were analyzed. The results show that the total VOC emissions from forests in China are 8565.76 Gg, of which isoprene is 5689.38 Gg (66.42%), monoterpenes is 1343.95 Gg (15.69%), and other VOC is 1532.43 Gg (17.89%). VOC emissions have significant species variation. Quercus is the main species responsible for emission, contributing 45.22% of the total, followed by Picea and Pinus massoniana with 6.34% and 5.22%, respectively. Southwest and Northeast China are the major emission regions. In specific, Yunnan, Sichuan, Heilongjiang, Jilin and Shaanxi are the top five provinces producing the most VOC emissions from forests, and their contributions to the total are 15.09%, 12.58%, 10.35%, 7.49% and 7.37%, respectively. Emissions from these five provinces occupy more than half (52.88%) of the national emissions. Besides, VOC emissions show remarkable seasonal variation. Emissions in summer are the largest, accounting for 56.66% of the annual. Forests of different ages have different emission contribution. Half-mature forests play a key role and contribute 38.84% of the total emission from forests.

  16. Database of normal human cerebral blood flow, cerebral blood volume, cerebral oxygen extraction fraction and cerebral metabolic rate of oxygen measured by positron emission tomography with {sup 15}O-labelled carbon dioxide or water, carbon monoxide and oxygen: a multicentre study in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi [Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita (Japan); Department of Nuclear Medicine and Radiology, Division of Brain Sciences, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-Machi, 980-8575, Aoba-Ku, Sendai (Japan); Kanno, Iwao [Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita (Japan); Kato, Chietsugu [Department of Nuclear Medicine, Hokkaido University School of Medicine, Sapporo (Japan); Sasaki, Toshiaki [Cyclotoron Research Center, Iwate Medical University, Morioka (Japan); Ishii, Kenji [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Tokyo (Japan); Ouchi, Yasuomi [Positron Medical Center, Hamamatsu Medical Center, Hamakita (Japan); Iida, Akihiko [Nagoya City Rehabilitation Center, Nagoya (Japan); Okazawa, Hidehiko [PET Unit, Research Institute, Shiga Medical Center, Moriyama (Japan); Hayashida, Kohei [Department of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Tsuyuguchi, Naohiro [Department of Neurosurgery, Osaka City University Medical School, Osaka (Japan); Ishii, Kazunari [Division of Imaging Research, Hyogo Institute for Aging Brain and Cognitive Disorders, Himeji, Hyogo (Japan); Kuwabara, Yasuo [Department of Radiology, Faculty of Medicine, Kyushu University, Fukuoka (Japan); Senda, Michio [Department of Image-based Medicine, Institute of Biomedical Research and Innovation, Kobe (Japan)

    2004-05-01

    Measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO{sub 2}) by positron emission tomography (PET) with oxygen-15 labelled carbon dioxide (C{sup 15}O{sub 2}) or {sup 15}O-labelled water (H{sub 2}{sup 15}O), {sup 15}O-labelled carbon monoxide (C{sup 15}O) and {sup 15}O-labelled oxygen ({sup 15}O{sub 2}) is useful for diagnosis and treatment planning in cases of cerebrovascular disease. The measured values theoretically depend on various factors, which may differ between PET centres. This study explored the applicability of a database of {sup 15}O-PET by examining between-centre and within-centre variation in values. Eleven PET centres participated in this multicentre study; seven used the steady-state inhalation method, one used build-up inhalation and three used bolus administration of C{sup 15}O{sub 2} (or H{sub 2}{sup 15}O) and {sup 15}O{sub 2}. All used C{sup 15}O for measurement of CBV. Subjects comprised 70 healthy volunteers (43 men and 27 women; mean age 51.8{+-}15.1 years). Overall mean{+-}SD values for cerebral cortical regions were: CBF=44.4{+-}6.5 ml 100 ml{sup -1} min{sup -1}; CBV=3.8{+-}0.7 ml 100 ml{sup -1}; OEF=0.44{+-}0.06; CMRO{sub 2}=3.3{+-}0.5 ml 100 ml{sup -1} min{sup -1}. Significant between-centre variation was observed in CBV, OEF and CMRO{sub 2} by one-way analysis of variance. However, the overall inter-individual variation in CBF, CBV, OEF and CMRO{sub 2} was acceptably small. Building a database of normal cerebral haemodynamics obtained by the{sup 15}O-PET methods may be practicable. (orig.)

  17. Sensory emission rates from personal computers and television sets

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Bako-Biro, Zsolt; Baginska, S.

    2003-01-01

    Sensory emissions from personal computers (PCs), PC monitors + PC towers, and television sets (TVs) having been in operation for 50, 400 and 600 h were assessed by a panel of 48 subjects. One brand of PC tower and four brands of PC monitors were tested. Within each brand, cathode-ray tube (CRT......) and thin-flat-transistor (TFT) monitors were selected. Two brands of TVs were tested. All brands are prevalent on the world market. The assessments were conducted in low-polluting 40 m3 test offices ventilated with a constant outdoor air change rate of 1.3 ± 0.2 h–1 corresponding to 7 L/s per PC or TV...... with two units placed at a time in the test offices; air temperature was controlled at 22 ± 0.1°C and relative humidity at 41 ± 0.5%. The subjects entered the offices individually and immediately assessed the air quality. They did not see the PCs or TVs that were placed behind a screen and were...

  18. Dust from southern Africa: rates of emission and biogeochemical properties

    Science.gov (United States)

    Bhattachan, A.; D'Odorico, P.; Zobeck, T. M.; Okin, G. S.; Dintwe, K.

    2012-12-01

    The stabilized linear dunefields in the southern Kalahari show signs of reactivation due to reduced vegetation cover owing to drought and/or overgrazing. It has been demonstrated with a laboratory dust generator that the southern Kalahari soils are good emitters of dust and that large-scale dune reactivation can potentially make the region an important dust source in the relatively low-dust Southern Hemisphere. We show that emergence of the southern Kalahari as a new dust source may affect ocean biogeochemistry as the soils are rich in soluble iron and the dust from the southern Kalahari commonly reaches the Southern Ocean. We investigate the biogeochemical properties of the fine fraction of soil from the Kalahari dunes and compare them to those of currently active dust sources such as the Makgadikgadi and the Etosha pans as well as other smaller pans in the region. Using field measurements of sediment fluxes and satellite images, we calculate the rates of dust emission from the southern Kalahari under different land cover scenarios. To assess the reversibility of dune reactivation in the southern Kalahari, we investigate the resilience of dunefield vegetation by looking at changes in soil nutrients, fine soil fractions, and seed bank in areas affected by intense denudation.

  19. Left ventricular volume determination from single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Bunker, S.R.; Hartshorne, M.F.; Schmidt, W.P.; Cawthon, M.A.; Karl, R.D. Jr.; Bauman, J.M.; Howard, W.H. III; Rubal, B.J.

    1985-01-01

    To compare the accuracy of single-photon emission computed tomography (SPECT) with that of contrast cineangiography in measuring left ventricular end-diastolic volume, 25 consecutive patients undergoing catheterizaiton for coronary artery or valvular heart disease were first evaluated scintigraphically. SPECT volume values showed a high degree of correlation with those determined by angiography with a standard error of the estimate of 23 ml. SPECT offers a highly accurate and essentially noninvasive method for measuring chamber volumes that is independent of geometric assumptions about ventricular configuration and chest wall attenuation and does not require blood sample counting

  20. Left ventricular volume determination from single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bunker, S.R.; Hartshorne, M.F.; Schmidt, W.P.; Cawthon, M.A.; Karl, R.D. Jr.; Bauman, J.M.; Howard, W.H. III; Rubal, B.J.

    1985-02-01

    To compare the accuracy of single-photon emission computed tomography (SPECT) with that of contrast cineangiography in measuring left ventricular end-diastolic volume, 25 consecutive patients undergoing catheterizaiton for coronary artery or valvular heart disease were first evaluated scintigraphically. SPECT volume values showed a high degree of correlation with those determined by angiography with a standard error of the estimate of 23 ml. SPECT offers a highly accurate and essentially noninvasive method for measuring chamber volumes that is independent of geometric assumptions about ventricular configuration and chest wall attenuation and does not require blood sample counting.

  1. Diurnal Variation in the Basal Emission Rate of Isoprene

    Science.gov (United States)

    Jennifer Funk; Clive G. Jones; Christine J. Baker; Heather M. Fuller; Christian P. Giardina; Manuel T. Lerdua

    2003-01-01

    Isoprene is emitted from numerous plant species and profoundly influences tropospheric chemistry. Due to the short lifetime of isoprene in the atmosphere, developing an understanding of emission patterns at small time scales is essential for modeling regional atmospheric chemistry processes. Previous studies suggest that diurnal fluctuations in isoprene emission may be...

  2. Intake plenum volume and its influence on the engine performance, cyclic variability and emissions

    International Nuclear Information System (INIS)

    Ceviz, M.A.

    2007-01-01

    Intake manifold connects the intake system to the intake valve of the engine and through which air or air-fuel mixture is drawn into the cylinder. Details of the flow in intake manifolds are extremely complex. Recently, most of engine companies are focused on variable intake manifold technology due to their improvement on engine performance. This paper investigates the effects of intake plenum volume variation on engine performance and emissions to constitute a base study for variable intake plenum. Brake and indicated engine performance characteristics, coefficient of variation in indicated mean effective pressure (COV imep ) as an indicator for cyclic variability, pulsating flow pressure in the intake manifold runner, and CO, CO 2 and HC emissions were taken into consideration to evaluate the effects of different plenum volumes. The results of this study showed that the variation in the plenum volume causes an improvement on the engine performance and the pollutant emissions. The brake torque and related performance characteristics improved pronouncedly about between 1700 and 2600 rpm by increasing plenum volume. Additionally, although the increase in the plenum volume caused the mixture leaner due to the increase in the intake runner pressure and lean mixtures inclined to increase the cyclic variability, a decrease was interestingly observed in the COV imep

  3. Narrow band flame emission from dieseline and diesel spray combustion in a constant volume combustion chamber

    KAUST Repository

    Wu, Zengyang

    2016-08-18

    In this paper, spray combustion of diesel (No. 2) and diesel-gasoline blend (dieseline: 80% diesel and 20% gasoline by volume) were investigated in an optically accessible constant volume combustion chamber. Effects of ambient conditions on flame emissions were studied. Ambient oxygen concentration was varied from 12% to 21% and three ambient temperatures were selected: 800 K, 1000 K and 1200 K. An intensified CCD camera coupled with bandpass filters was employed to capture the quasi-steady state flame emissions at 430 nm and 470 nm bands. Under non-sooting conditions, the narrow-band flame emissions at 430 nm and 470 nm can be used as indicators of CH∗ (methylidyne) and HCHO∗ (formaldehyde), respectively. The lift-off length was measured by imaging the OH∗ chemiluminescence at 310 nm. Flame emission structure and intensity distribution were compared between dieseline and diesel at wavelength bands. Flame emission images show that both narrow band emissions become shorter, thinner and stronger with higher oxygen concentration and higher ambient temperature for both fuels. Areas of weak intensity are observed at the flame periphery and the upstream for both fuels under all ambient conditions. Average flame emission intensity and area were calculated for 430 nm and 470 nm narrow-band emissions. At a lower ambient temperature the average intensity increases with increasing ambient oxygen concentration. However, at the 1200 K ambient temperature condition, the average intensity is not increasing monotonically for both fuels. For most of the conditions, diesel has a stronger average flame emission intensity than dieseline for the 430 nm band, and similar phenomena can be observed for the 470 nm band with 800 K and 1200 K ambient temperatures. However, for the 1000 K ambient temperature cases, dieseline has stronger average flame emission intensities than diesel for all oxygen concentrations at 470 nm band. Flame emissions for the two bands have a

  4. Spontaneous Emission and Energy Transfer Rates Near a Coated Metallic Cylinder

    OpenAIRE

    BRADLEY, LOUISE

    2014-01-01

    PUBLISHED The spontaneous emission and energy transfer rates of quantum systems in proximity to a dielectrically coated metallic cylinder are investigated using a Green's tensor formalism. The excitation of surface plasmon modes can significantly modify these rates. The spontaneous emission and energy transfer rates are investigated as a function of the material and dimensions of the core and coating, as well as the emission wavelength of the donor. For the material of the core we consider...

  5. Emissions of Water and Carbon Dioxide from Fossil-Fuel Combustion Contribute Directly to Ocean Mass and Volume Increases

    Science.gov (United States)

    Skuce, A. G.

    2014-12-01

    The direct, non-climate, contribution of carbon dioxide and water emissions from fossil-fuel (FF) combustion to the volume and mass of the oceans has been omitted from estimates of sea-level rise (SLR) in IPCC reports. Following the method of Gornitz et al. (1997), H2O emissions are estimated using carbon emissions from the Carbon Dioxide Information Analysis Center, along with typical carbon and hydrogen contents of FF. Historic H2O emissions from 1750 to 2010 amount to 430 ±50 PgH2O, equivalent to 1.2 ±0.2 mmSLR. Sometime in this decade the volume of H2O from historic FF combustion will exceed the volume of Lake Erie (480 km3). CO2 dissolved in the ocean increases the seawater volume by 31-33 mL mol-1 CO2. From 1750 to 2010, 370 ±70 PgCO2 from FF combustion has dissolved in the oceans, causing 0.7 ±0.2 mmSLR. Combined H2O+CO2emissions from FF have therefore added 1.9 ±0.4 mm to sea levels in the Industrial Era. Combustion of FF in 2010 resulted in emissions of 32 PgCO2 and 12 ±1 PgH2O. SLR contributions for that year from FF emissions were 0.033 ±0.005 mm from H2O and 0.011±0.003 mm from dissolved CO2, a total rate of 0.044 ±0.008 mm yr-1. Emissions incorporated in socio-economic models underlying the RCP 8.5 and 2.6 scenarios are used along with concentration-driven CMIP5 Earth System Models results to estimate future sea-level rise from FF combustion. From 2010 to 2100, RCP8.5 and 2.6 models respectively produce 9 ±2 mmSLR and 5 ±1 mmSLR from FF H2O+CO2. For perspective, these amounts are larger than the modelled contributions from loss of glaciers in the Andes. The direct contribution of FF emissions to SLR is small (1-2%) relative to current rates and projected estimates under RCP scenarios up to 2100. The magnitude is similar to SLR estimates from other minor sources such as the melting of floating ice, land-use emissions and produced water from oil operations, none of which are currently included in SLR assessments. As uncertainties in

  6. Combining rate-based and cap-and-trade emissions policies

    International Nuclear Information System (INIS)

    Fischer, Carolyn

    2003-12-01

    Rate-based emissions policies (like tradable performance standards, TPS) fix average emissions intensity, while cap-and-trade (CAT) policies fix total emissions. This paper shows that unfettered trade between rate-based and cap-and-trade programs always raises combined emissions, except when product markets are related in particular ways. Gains from trade are fully passed on to consumers in the rate-based sector, resulting in more output and greater emissions allocations. We consider several policy options to offset the expansion, including a tax, an 'exchange rate' to adjust for relative permit values, output-based allocation (OBA) for the rate-based sector, and tightening the cap. A range of combinations of tighter allocations could improve situations in both sectors with trade while holding emissions constant

  7. Comparison of real-world and certification emission rates for light duty gasoline vehicles.

    Science.gov (United States)

    Khan, Tanzila; Frey, H Christopher

    2018-05-01

    U.S. light duty vehicles are subject to the U.S. Environmental Protection Agency (EPA) emission standards. Emission compliance is determined by certification testing of selected emissions from representative vehicles on standard driving cycles using chassis dynamometers. Test results are also used in many emission inventories. The dynamometer based emission rates are adjusted to provide the certification levels (CL), which must be lower than the standards for compliance. Although standard driving cycles are based on specific observations of real-world driving, they are not necessarily real-world representative. A systematic comparison of the real-world emission rates of U.S. light duty gasoline vehicles (LDGVs) versus CL, and emission standards has not been previously reported. The purpose of this work is to compare regulatory limits (both CLs and emission standards) and the real-world emissions of LDGVs. The sensitivity of the comparisons to cold start emission was assessed. Portable Emission Measurement Systems (PEMS) were used to measure hot stabilized exhaust emissions of 122 LDGVs on a specified 110 mile test route. Cold start emissions were measured with PEMS for a selected vehicle sample of 32 vehicles. Emissions were measured for carbon dioxide (CO 2 ), carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NO x ). For each vehicle, a Vehicle Specific Power (VSP) modal emission rate model was developed. The VSP modal rates were weighted by the standard driving cycles and real-world driving cycles to estimate the respective cycle average emission rates (CAERs). Measured vehicles were matched with certification test vehicles for comparison. For systematic trends in comparison, vehicles were classified into four groups based on the Tier 1 and Tier 2 emission regulation, and the vehicle type such as passenger car and passenger truck. Depending on the cycle-pollutant and the vehicle groups, hot stabilized CAERs are on average either statistically

  8. Small-volume amnioinfusion: a potential stimulus of intrapartum fetal heart rate accelerations.

    Science.gov (United States)

    Wax, Joseph R; Flaherty, Nina; Pinette, Michael G; Blackstone, Jacquelyn; Cartin, Angelina

    2004-02-01

    We describe a recurrent nonreassuring fetal heart rate pattern in which small-volume amnioinfusions apparently evoked fetal heart rate accelerations suggested fetal well-being, allowing that progressive labor that culminated in the vaginal delivery of a healthy infant.

  9. Impacts of Aging Emission Control Systems on In-Use Heavy-Duty Diesel Truck Emission Rates

    Science.gov (United States)

    Preble, C.; Cados, T.; Harley, R.; Kirchstetter, T.

    2017-12-01

    Heavy-duty diesel trucks are a major source of nitrogen oxides (NOx) and black carbon (BC) in urban environments, contributing to persistent ozone and particulate matter air quality problems. Recently, diesel particle filter (DPF) and selective catalytic reduction (SCR) emission control systems have become standard equipment on new trucks. Particle filters can also be installed as a retrofit on older engines. Prior work has shown that exhaust filters and SCR systems effectively reduce BC and NOx emission rates by up to 90 and 80%, respectively (Preble et al., ES&T 2015). There is concern, however, that DPFs may promote the formation of ultrafine particles (UFP) and increase tailpipe emissions of nitrogen dioxide (NO2). Additionally, urea-based SCR systems for NOx control may form nitrous oxide (N2O), an important contributor to stratospheric ozone depletion. The effectiveness of these emission controls has been thoroughly evaluated in the laboratory, but the long-term durability of in-use systems and their impacts on co-emitted species have not been well characterized. To evaluate the in-use performance of DPF and SCR systems, pollutant emissions from thousands of diesel trucks were measured over several years at the Port of Oakland and the Caldecott Tunnel in the San Francisco Bay Area. Pollutants present in the exhaust plumes of individual trucks were measured at high time resolution (≥1 Hz) as trucks passed under a mobile lab stationed on an overpass. Fuel-based emission factors (g pollutant emitted per kg fuel burned) were calculated for individual trucks and linked via recorded license plates to vehicle attributes, including engine model year and installed emission control systems. Use of DPFs reduced the BC emission rate by up to 95% at both locations. SCR systems were more effective at reducing NOx emissions under the uphill, highway driving conditions at the Caldecott Tunnel. The emission rates of co-emitted species NO2, UFP, and N2O depended on driving

  10. TRANSIT BUS LOAD-BASED MODAL EMISSION RATE MODEL DEVELOPMENT

    Science.gov (United States)

    Heavy-duty diesel vehicles (HDDVs) operations are a major source of oxides of nitrogen (NOx) and particulate matter (PM) emissions in metropolitan area nationwide. Although HD¬DVs constitute a small portion of the on-road fleet, they typically contribute more than 45% of NOx and ...

  11. Dose rate from the square volume radiation source

    International Nuclear Information System (INIS)

    Karpov, V.I.

    1978-01-01

    The expression for determining the dose rate from a three-dimensional square flat-parallel source of any dimensions is obtained. A simplified method for integrating the resultant expression is proposed. A comparison of the calculation results with the results by the Monte Carlo method has shown them to coincide within 6-8%. Since buildings and structures consist of rectangular elements, the method is recommended for practical calculations of dose rates in residential buildings

  12. Linearity between temperature peak and bio-energy CO2 emission rates

    International Nuclear Information System (INIS)

    Cherubini, Francesco; Bright, Ryan M.; Stromman, Anders H.; Gasser, Thomas; Ciais, Philippe

    2014-01-01

    Many future energy and emission scenarios envisage an increase of bio-energy in the global primary energy mix. In most climate impact assessment models and policies, bio-energy systems are assumed to be carbon neutral, thus ignoring the time lag between CO 2 emissions from biomass combustion and CO 2 uptake by vegetation. Here, we show that the temperature peak caused by CO 2 emissions from bio-energy is proportional to the maximum rate at which emissions occur and is almost insensitive to cumulative emissions. Whereas the carbon-climate response (CCR) to fossil fuel emissions is approximately constant, the CCR to bio-energy emissions depends on time, biomass turnover times, and emission scenarios. The linearity between temperature peak and bio-energy CO 2 emission rates resembles the characteristic of the temperature response to short-lived climate forcers. As for the latter, the timing of CO 2 emissions from bio-energy matters. Under the international agreement to limit global warming to 2 C by 2100, early emissions from bio-energy thus have smaller contributions on the targeted temperature than emissions postponed later into the future, especially when bio-energy is sourced from biomass with medium (50-60 years) or long turnover times (100 years). (authors)

  13. Emission rates of regulated pollutants from on-road heavy-duty diesel vehicles

    Science.gov (United States)

    Shah, Sandip D.; Johnson, Kent C.; Wayne Miller, J.; Cocker, David R.

    Emissions from heavy-duty diesel (HDD) vehicles are affected by many factors. Changes in engine technology, operating mode, fuel properties, vehicle speed and ambient conditions can have significant effects on emission rates of regulated species. This paper presents the results of on-road emissions testing of 11 HDD vehicles (model years 1996-2000) over the ARB Four Phase driving schedule and the urban dynamometer driving schedule (UDDS). Emission rates were found to be highly dependent on vehicle operating mode. Per mile NO x emission rates for vehicle operation at low speeds, in simulated congested traffic, were three times higher per mile emissions then while cruising on the freeway. Comparisons of NO x emission factors to EMFAC baseline emission factors were within 5-40% for vehicles of various model years tested over the UDDS. A comparison of NO x emission factors for a weighted average of the ARB four phase driving schedule yielded values within 17-57% of EMFAC values. Generally, particulate matter (PM) emission rates were lower than EMFAC values.

  14. Estimating the Effects of Exchange Rate Volatility on Export Volumes

    OpenAIRE

    Wang, Kai-Li; Barrett, Christopher B.

    2007-01-01

    This paper takes a new empirical look at the long-standing question of the effect of exchange rate volatility on international trade flows by studying the case of Taiwan's exports to the United States from 1989-1998. In particular, we employ sectoral-level, monthly data and an innovative multivariate GARCH-M estimator with corrections for leptokurtic errors. This estimator allows for the possibility that traders' forward-looking contracting behavior might condition the way in which exchange r...

  15. Particulate emission rates from light-duty vehicles in the South Coast Air Quality Management District

    International Nuclear Information System (INIS)

    Durbin, T.D.; Norbeck, J.M.; Smith, M.R.; Truex, T.J.

    1999-01-01

    This paper presents the results of a particulate emission rate study conducted on 129 light-duty gasoline and 19 light-duty diesel vehicles for the Coordinating Research Council's (CRC's) Project E-24-2. Total particulate emission rates for newer gasoline vehicles were low with modest increases with vehicle age and older technology. Average FTP particulate emission rates as a function of model year for gasoline vehicles were found to be 2.5 mg/mi for 1991 and newer models, 14.4 mg/mi for 1986--1990 models, 49.0 mg/mi for 1981--1985 models, and 33.8 mg/mi for 1980 and older models. High gaseous emitters were found to have approximately 5--10 times the particulate emission rates of normal emitters. The diesel vehicles had an average particulate emission rate of 561 mg/mi. It should be noted that the light-duty diesel vehicles were predominantly older, pre-1985 vehicles; the 1985 and newer diesel vehicles had substantially lower particulate emissions, i.e., less than 100 mg/mi. Emission inventory estimates in the South Coast Air Basin based on the fleet emission rates were higher than those obtained using the default values in EMFAC7G, due primarily to the contribution of high emitters

  16. Effects of Injection Rate Profile on Combustion Process and Emissions in a Diesel Engine

    Directory of Open Access Journals (Sweden)

    Fuqiang Bai

    2017-01-01

    Full Text Available When multi-injection is implemented in diesel engine via high pressure common rail injection system, changed interval between injection pulses can induce variation of injection rate profile for sequential injection pulse, though other control parameters are the same. Variations of injection rate shape which influence the air-fuel mixing and combustion process will be important for designing injection strategy. In this research, CFD numerical simulations using KIVA-3V were conducted for examining the effects of injection rate shape on diesel combustion and emissions. After the model was validated by experimental results, five different shapes (including rectangle, slope, triangle, trapezoid, and wedge of injection rate profiles were investigated. Modeling results demonstrate that injection rate shape can have obvious influence on heat release process and heat release traces which cause different combustion process and emissions. It is observed that the baseline, rectangle (flat, shape of injection rate can have better balance between NOx and soot emissions than the other investigated shapes. As wedge shape brings about the lowest NOx emissions due to retarded heat release, it produces the highest soot emissions among the five shapes. Trapezoid shape has the lowest soot emissions, while its NOx is not the highest one. The highest NOx emissions were produced by triangle shape due to higher peak injection rate.

  17. Tumor Volume Reduction Rate After Preoperative Chemoradiotherapy as a Prognostic Factor in Locally Advanced Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yeo, Seung-Gu [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Radiation Oncology, Soonchunhyang University College of Medicine, Cheonan (Korea, Republic of); Kim, Dae Yong, E-mail: radiopiakim@hanmail.net [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Park, Ji Won; Oh, Jae Hwan; Kim, Sun Young; Chang, Hee Jin; Kim, Tae Hyun; Kim, Byung Chang; Sohn, Dae Kyung; Kim, Min Ju [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of)

    2012-02-01

    Purpose: To investigate the prognostic significance of tumor volume reduction rate (TVRR) after preoperative chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC). Methods and Materials: In total, 430 primary LARC (cT3-4) patients who were treated with preoperative CRT and curative radical surgery between May 2002 and March 2008 were analyzed retrospectively. Pre- and post-CRT tumor volumes were measured using three-dimensional region-of-interest MR volumetry. Tumor volume reduction rate was determined using the equation TVRR (%) = (pre-CRT tumor volume - post-CRT tumor volume) Multiplication-Sign 100/pre-CRT tumor volume. The median follow-up period was 64 months (range, 27-99 months) for survivors. Endpoints were disease-free survival (DFS) and overall survival (OS). Results: The median TVRR was 70.2% (mean, 64.7% {+-} 22.6%; range, 0-100%). Downstaging (ypT0-2N0M0) occurred in 183 patients (42.6%). The 5-year DFS and OS rates were 77.7% and 86.3%, respectively. In the analysis that included pre-CRT and post-CRT tumor volumes and TVRR as continuous variables, only TVRR was an independent prognostic factor. Tumor volume reduction rate was categorized according to a cutoff value of 45% and included with clinicopathologic factors in the multivariate analysis; ypN status, circumferential resection margin, and TVRR were significant prognostic factors for both DFS and OS. Conclusions: Tumor volume reduction rate was a significant prognostic factor in LARC patients receiving preoperative CRT. Tumor volume reduction rate data may be useful for tailoring surgery and postoperative adjuvant therapy after preoperative CRT.

  18. High energy effects on D-brane and black hole emission rates

    International Nuclear Information System (INIS)

    Das, S.; Dasgupta, A.; Sarkar, T.

    1997-01-01

    We study the emission of scalar particles from a class of near-extremal five-dimensional black holes and the corresponding D-brane configuration at high energies. We show that the distribution functions and the black hole greybody factors are modified in the high energy tail of the Hawking spectrum in such a way that the emission rates exactly match. We extend the results to charged scalar emission and to four dimensions. copyright 1997 The American Physical Society

  19. Effects of exchange rate volatility on export volume and prices of forest products

    Science.gov (United States)

    Sijia Zhang; Joseph Buongiorno

    2010-01-01

    The relative value of currencies varies considerably over time. These fluctuations bring uncertainty to international traders. As a result, the volatility in exchange rate movements may influence the volume and the price of traded commodities. The volatility of exchange rates was measured by the variance of residuals in a GARCH(1,1) model of the exchange rate. We...

  20. Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement

    International Nuclear Information System (INIS)

    Masuda, Takahiko; Hara, Hideaki; Miyamoto, Yuki; Kuma, Susumu; Nakano, Itsuo; Ohae, Chiaki; Sasao, Noboru; Tanaka, Minoru; Uetake, Satoshi; Yoshimi, Akihiro; Yoshimura, Koji; Yoshimura, Motohiko

    2015-01-01

    We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10 15 from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect

  1. Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Takahiko, E-mail: masuda@okayama-u.ac.jp; Hara, Hideaki; Miyamoto, Yuki [Okayama University, Research Core for Extreme Quantum World (Japan); Kuma, Susumu [Atomic, Molecular and Optical Physics Laboratory, RIKEN (Japan); Nakano, Itsuo [Okayama University, Research Core for Extreme Quantum World (Japan); Ohae, Chiaki [University of Electro-Communications, Department of Engineering Science (Japan); Sasao, Noboru [Okayama University, Research Core for Extreme Quantum World (Japan); Tanaka, Minoru [Osaka University, Department of Physics (Japan); Uetake, Satoshi [Okayama University, Research Center of Quantum Universe (Japan); Yoshimi, Akihiro; Yoshimura, Koji [Okayama University, Research Core for Extreme Quantum World (Japan); Yoshimura, Motohiko [Okayama University, Research Center of Quantum Universe (Japan)

    2015-11-15

    We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10{sup 15} from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect.

  2. The relationship between sap-flow rate and sap volume in dormant sugar maples

    Science.gov (United States)

    William J. Gabriel; Russell S. Walters; Donald W. Seegrist

    1972-01-01

    Sap-flow rate is closely correlated with the sap volume produced by dormant sugar maple trees (Acer saccharum Marsh.) and could be used in making phenotypic selections of trees for superior sap production.

  3. Combined use of positron emission tomography and volume doubling time in lung cancer screening with low-dose CT scanning

    DEFF Research Database (Denmark)

    Ashraf, H; Dirksen, A; Jakobsen, Annika Loft

    2011-01-01

    In lung cancer screening the ability to distinguish malignant from benign nodules is a key issue. This study evaluates the ability of positron emission tomography (PET) and volume doubling time (VDT) to discriminate between benign and malignant nodules.......In lung cancer screening the ability to distinguish malignant from benign nodules is a key issue. This study evaluates the ability of positron emission tomography (PET) and volume doubling time (VDT) to discriminate between benign and malignant nodules....

  4. Validated analytical modeling of diesel engine regulated exhaust CO emission rate

    Directory of Open Access Journals (Sweden)

    Waleed F Faris

    2016-06-01

    Full Text Available Albeit vehicle analytical models are often favorable for explainable mathematical trends, no analytical model has been developed of the regulated diesel exhaust CO emission rate for trucks yet. This research unprecedentedly develops and validates for trucks a model of the steady speed regulated diesel exhaust CO emission rate analytically. It has been found that the steady speed–based CO exhaust emission rate is based on (1 CO2 dissociation, (2 the water–gas shift reaction, and (3 the incomplete combustion of hydrocarbon. It has been found as well that the steady speed–based CO exhaust emission rate based on CO2 dissociation is considerably less than the rate that is based on the water–gas shift reaction. It has also been found that the steady speed–based CO exhaust emission rate based on the water–gas shift reaction is the dominant source of CO exhaust emission. The study shows that the average percentage of deviation of the steady speed–based simulated results from the corresponding field data is 1.7% for all freeway cycles with 99% coefficient of determination at the confidence level of 95%. This deviation of the simulated results from field data outperforms its counterpart of widely recognized models such as the comprehensive modal emissions model and VT-Micro for all freeway cycles.

  5. Odour emission inventory of German wastewater treatment plants--odour flow rates and odour emission capacity.

    Science.gov (United States)

    Frechen, F-B

    2004-01-01

    Wastewater Treatment plants can cause odour emissions that may lead to significant odour annoyance in their vicinity. Thus, over the past 20 years, several measurements were taken of the odour emissions that occur at WWTPs of different sizes, treatment technology, plant design and under different operating conditions. The specific aspects of odour sampling and measurement have to be considered. I presented some of the results of my odour emission measurements 11 years ago. However, it is now necessary to update the figures by evaluating newer measurement results obtained from measurements taken from 1994 to 2003. These are presented in this paper. Also, the paper highlights the odour emission capacity (OEC) measurement technique which characterises liquids and can be used to assess the results achieved by different types of treatment in the liquid phase, e.g. in a sewerage system. In addition, the OEC is a suitable parameter to set standards for the odorant content of industrial wastewaters that are discharged into the publicly owned sewerage system.

  6. Effects of respiratory rate and tidal volume on gas exchange in total liquid ventilation.

    Science.gov (United States)

    Bull, Joseph L; Tredici, Stefano; Fujioka, Hideki; Komori, Eisaku; Grotberg, James B; Hirschl, Ronald B

    2009-01-01

    Using a rabbit model of total liquid ventilation (TLV), and in a corresponding theoretical model, we compared nine tidal volume-respiratory rate combinations to identify a ventilator strategy to maximize gas exchange, while avoiding choked flow, during TLV. Nine different ventilation strategies were tested in each animal (n = 12): low [LR = 2.5 breath/min (bpm)], medium (MR = 5 bpm), or high (HR = 7.5 bpm) respiratory rates were combined with a low (LV = 10 ml/kg), medium (MV = 15 ml/kg), or high (HV = 20 ml/kg) tidal volumes. Blood gases and partial pressures, perfluorocarbon gas content, and airway pressures were measured for each combination. Choked flow occurred in all high respiratory rate-high volume animals, 71% of high respiratory rate-medium volume (HRMV) animals, and 50% of medium respiratory rate-high volume (MRHV) animals but in no other combinations. Medium respiratory rate-medium volume (MRMV) resulted in the highest gas exchange of the combinations that did not induce choke. The HRMV and MRHV animals that did not choke had similar or higher gas exchange than MRMV. The theory predicted this behavior, along with spatial and temporal variations in alveolar gas partial pressures. Of the combinations that did not induce choked flow, MRMV provided the highest gas exchange. Alveolar gas transport is diffusion dominated and rapid during gas ventilation but is convection dominated and slow during TLV. Consequently, the usual alveolar gas equation is not applicable for TLV.

  7. Volatile Organic Compound Concentrations and Emission Rates in New Manufactured and Site-Built Houses

    Energy Technology Data Exchange (ETDEWEB)

    Armin Rudd

    2008-10-30

    This study was conducted with the primary objective of characterizing and comparing the airborne concentrations and the emission rates of total VOCs and selected individual VOCs, including formaldehyde, among a limited number of new manufactured and site-built houses.

  8. Compilation of air pollutant emission factors. Volume 1. Stationary point and area sources. Supplement E

    International Nuclear Information System (INIS)

    1992-10-01

    In the Supplement to the Fourth Edition of AP-42 Volume I, new or revised emissions data are presented for Anthracite Coal Combustion; Natural Gas Combustion; Liquified Petroleum Gas Combustion; Wood Waste Combustion In Boilers; Bagasse Combustion In Sugar Mills; Residential Fireplaces; Residential Wood Stoves; Waste Oil Combustion; Automobile Body Incineration; Conical Burners; Open Burning; Stationary Gas Turbines for Electricity Generation; Heavy Duty Natural Gas Fired Pipeline Compressor Engines; Gasoline and Diesel Industrial Engines; Large Stationary Diesel and All Stationary Dual Fuel Engines; Soap and Detergents; and Storage of Organic Liquids

  9. Test Method for High β Particle Emission Rate of 63Ni Source Plate

    OpenAIRE

    ZHANG Li-feng

    2015-01-01

    For the problem of measurement difficulties of β particle emission rate of Ni-63 source plate used for Ni-63 betavoltaic battery, a relative test method of scintillation current method was erected according to the measurement principle of scintillation detector.β particle emission rate of homemade Ni-63 source plate was tested by the method, and the test results were analysed and evaluated, it was initially thought that scintillation current method was a feasible way of testing β particle emi...

  10. Does nitrogen fertilizer application rate to corn affect nitrous oxide emissions from the rotated soybean crop?

    Science.gov (United States)

    Iqbal, Javed; Mitchell, David C; Barker, Daniel W; Miguez, Fernando; Sawyer, John E; Pantoja, Jose; Castellano, Michael J

    2015-05-01

    Little information exists on the potential for N fertilizer application to corn ( L.) to affect NO emissions during subsequent unfertilized crops in a rotation. To determine if N fertilizer application to corn affects NO emissions during subsequent crops in rotation, we measured NO emissions for 3 yr (2011-2013) in an Iowa, corn-soybean [ (L.) Merr.] rotation with three N fertilizer rates applied to corn (0 kg N ha, the recommended rate of 135 kg N ha, and a high rate of 225 kg N ha); soybean received no N fertilizer. We further investigated the potential for a winter cereal rye ( L.) cover crop to interact with N fertilizer rate to affect NO emissions from both crops. The cover crop did not consistently affect NO emissions. Across all years and irrespective of cover crop, N fertilizer application above the recommended rate resulted in a 16% increase in mean NO flux rate during the corn phase of the rotation. In 2 of the 3 yr, N fertilizer application to corn (0-225 kg N ha) did not affect mean NO flux rates from the subsequent unfertilized soybean crop. However, in 1 yr after a drought, mean NO flux rates from the soybean crops that received 135 and 225 kg N ha N application in the corn year were 35 and 70% higher than those from the soybean crop that received no N application in the corn year. Our results are consistent with previous studies demonstrating that cover crop effects on NO emissions are not easily generalizable. When N fertilizer affects NO emissions during a subsequent unfertilized crop, it will be important to determine if total fertilizer-induced NO emissions are altered or only spread across a greater period of time. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  11. Determination of Summertime VOC Emission Rates from Produced Water Ponds in the Uintah Basin

    Science.gov (United States)

    Martin, R. S.; Woods, C.; Lyman, S.

    2013-12-01

    The observance of excess ozone concentrations in Utah's Uintah Basin over past several years has prompted several investigations into the extent and causes of the elevated ozone. Among these is the assessment of potential emissions of reactive VOCs. Evaporation ponds, used a remediation technique for treatment of contaminated production and other waters, are one potential source of significant VOC emissions and is estimated that there are around 160 such ponds within the Uintah Basin's oil and gas production areas. In June 2012 VOC emission rates for several reactive VOCs were derived for an evaporation facility consisting of a small inlet pond (≈0.03 acres) and two larger, serial ponds (≈4.3 acres each). The emission rates were determined over three sampling periods using an inverse modeling approach. Under this methodology, ambient VOC concentrations are determined at several downwind locations through whole-air collection into SUMMA canisters, followed by GC/MS quantification and compared with predicted concentrations using an EPA-approved dispersion model, AERMOD. The presumed emission rates used within the model were then adjusted until the modeled concentrations approach the observed concentrations. The derived emission rates for the individual VOCs were on the order of 10-3 g/s/m2 from the inlet pond and 10-6 g/s/m2 from the larger ponds. The emissions from the 1st pond in series after the inlet pond were about 3-4x the emissions from the 2nd pond. These combined emission rates are about an order of magnitude those reported for a single study in Colorado (Thoma, 2009). It should be noted, however, that the variability about each of the VOC emission rates was significant (often ×100% at the 95% confidence interval). Extrapolating these emission rates to the estimated total areas of all the evaporation ponds within Basin resulted in calculated Basin-wide VOC emissions 292,835 tons/yr. However, Bar-Ilan et al. (2009) estimated 2012 VOC oil and gas related

  12. Inductively coupled plasma emission spectroscopy. Part II: applications and fundamentals. Volume 2

    International Nuclear Information System (INIS)

    Boumans, P.W.J.M.

    1987-01-01

    This is the second part of the two-volume treatise by this well-known and respected author. This volume reviews applications of inductively coupled plasma atomic emission spectroscopy (ICP-AES), summarizes fundamental studies, and compares ICP-AES methods with other methods of analysis. The first six chapters are devoted to specific fields of application, including the following: metals and other industrial materials, geology, the environment, agriculture and food, biology and clinical analysis, and organic materials. The chapter on the analysis of organic materials also covers the special instrumental considerations required when organic solvents are introduced into an inductively coupled plasma. A chapter on the direct analysis of solids completes the first part of this volume. Each of the applications chapters begins with a summary of the types of samples that are encountered in that field, and the kinds of problems that an elemental analysis can help to solve. This is followed by a tutorial approach covering applicability, advantages, and limitations of the methods. The coverage is thorough, including sample handling, storage, and preparation, acid, and fusion dissolution, avoiding contamination, methods of preconcentration, the types of interferences that can be expected and ways to reduce them, and the types of ICP plasmas that are used. The second half of the volume covers fundamental studies of ICP-AES: basic processes of aerosol generation, plasma modeling and computer simulation, spectroscopic diagnostics, excitation mechanisms, and discharge characteristics. This section introduces the experimental and modeling methods that have been used to obtain fundamental information about ICPs

  13. Modeling air pollutant emissions from Indian auto-rickshaws: Model development and implications for fleet emission rate estimates

    Science.gov (United States)

    Grieshop, Andrew P.; Boland, Daniel; Reynolds, Conor C. O.; Gouge, Brian; Apte, Joshua S.; Rogak, Steven N.; Kandlikar, Milind

    2012-04-01

    Chassis dynamometer tests were conducted on 40 Indian auto-rickshaws with 3 different fuel-engine combinations operating on the Indian Drive Cycle (IDC). Second-by-second (1 Hz) data were collected and used to develop velocity-acceleration look-up table models for fuel consumption and emissions of CO2, CO, total hydrocarbons (THC), oxides of nitrogen (NOx) and fine particulate matter (PM2.5) for each fuel-engine combination. Models were constructed based on group-average vehicle activity and emissions data in order to represent the performance of a 'typical' vehicle. The models accurately estimated full-cycle emissions for most species, though pollutants with more variable emission rates (e.g., PM2.5) were associated with larger errors. Vehicle emissions data showed large variability for single vehicles ('intra-vehicle variability') and within the test group ('inter-vehicle variability'), complicating the development of a single model to represent a vehicle population. To evaluate the impact of this variability, sensitivity analyses were conducted using vehicle activity data other than the IDC as model input. Inter-vehicle variability dominated the uncertainty in vehicle emission modeling. 'Leave-one-out' analyses indicated that the model outputs were relatively insensitive to the specific sample of vehicles and that the vehicle samples were likely a reasonable representation of the Delhi fleet. Intra-vehicle variability in emissions was also substantial, though had a relatively minor impact on model performance. The models were used to assess whether the IDC, used for emission factor development in India, accurately represents emissions from on-road driving. Modeling based on Global Positioning System (GPS) activity data from real-world auto-rickshaws suggests that, relative to on-road vehicles in Delhi, the IDC systematically under-estimates fuel use and emissions; real-word auto-rickshaws consume 15% more fuel and emit 49% more THC and 16% more PM2.5. The models

  14. In vivo imaging of GABAA receptors using sequential whole-volume iodine-123 iomazenil single-photon emission tomography

    International Nuclear Information System (INIS)

    Busatto, G.F.; Pilowsky, L.S.; Costa, D.C.; Ell, P.J.; Lingford-Hughes, A.; Kerwin, R.W.

    1995-01-01

    Using a brain-dedicated triple-headed single-photon emission tomography (SPET) system, a sequential whole-volume imaging protocol has been devised to evaluate the regional distribution of iodine-123 iomazenil binding to GABA A receptors in the entire brain. The protocol was piloted in eight normal volunteers (seven males and one female; mean age, 24.8±3.9 years). The patterns obtained were largely compatible with the known distribution of GABA A receptors in the brain as reported in autoradiographic studies, with cerebral cortical regions, particularly the occipital and frontal cortices, displaying the highest 123 I-iomazenil uptake. Measures of time to peak uptake and tracer washout rates presented with the same pattern of regional variation, with later times to peak and slower washout rates in cortical regions compared to other brain areas. Semiquantitative analysis of the data using white matter/ventricle regions as reference demonstrated a plateau of specific 123 I-iomazenil binding in neocortical and cerebellar regions from 60-75 min onwards. These data demonstrate the feasibility of sequential, dynamic whole-volume 123 I-iomazenil SPET imaging. The protocol may be particularly useful in the investigation of neuropsychiatric conditions which are likely to involve more than one focus of GABA abnormalities, such as anxiety disorders and schizophrenia. (orig.)

  15. Acidifier application rate impacts on ammonia emissions from US roaster chicken houses

    Science.gov (United States)

    Shah, Sanjay B.; Grimes, Jesse L.; Oviedo-Rondón, Edgar O.; Westerman, Philip W.

    2014-08-01

    Due to its potential environmental and public health impacts, emissions of ammonia (NH3) as well as several other gases from US livestock farms may be regulated. Broiler houses are important sources of NH3 emissions. However, there are no emissions data from roaster (8-12 wk old broilers, ˜4 kg ea.) houses. Producers treat the litter in broiler houses with acidifiers, such as sodium bisulfate (SBS, NaHSO4) to reduce ammonia production and protect bird health. However, there is very little data on the effect of acidifiers, particularly at high application rates on ammonia emissions. The impact of different SBS application rates [High (0.95-1.46 kg m-2, whole house), Medium (0.73 kg m-2, whole house), Low (0.37-0.49 kg m-2, whole house), and Control (0.37-0.49 kg m-2, brood chamber)] on ammonia emissions was evaluated in commercial roaster houses over 22 months spanning eight flocks. Ammonia emission from each fan was measured with an acid scrubber that operated only when the fan operated. Emissions were calculated using >95% measured data with the rest being estimated using robust methods. Exhaust ammonia-N concentrations were inversely correlated with the SBS application rates. Emission rates on animal unit (AU, where 1 AU = 500 kg live-mass) basis (ER, g d-1 AU-1) were reduced by 27, 13, and 5%, respectively, in the High, Medium, and Low treatments vs. the Control treatment (mean: 100 g d-1 AU-1, range: 86-114 g d-1 AU-1). Emission rates for the Control treatment measured in this study on roasters were mostly higher than ERs in the literature. Differences in ERs are not only due to diet, environmental and management conditions, but also due to measurement methods.

  16. A dilatometer to measure the influence of cooling rate and melt shearing on specific volume

    NARCIS (Netherlands)

    van der Beek, M.H.E.; Peters, G.W.M.; Meijer, H.E.H.

    2005-01-01

    We developed a dilatometer to investigate the specific volume of polymers as a function of pressure (to 100 MPa), temperature (to 260 oC), cooling rate (to 80 C/s), and shear rate (to 77 1/s). The dilatometeris based on the principle of con¯ned compression and comprises of a pressure cell used in

  17. Emissions of greenhouse gases from the use of transportation fuels and electricity. Volume 2: Appendixes A--S

    Energy Technology Data Exchange (ETDEWEB)

    DeLuchi, M.A. [Argonne National Lab., IL (United States)]|[Univ. of California, Davis, CA (United States). Inst. of Transportation Studies

    1993-11-01

    This volume contains the appendices to the report on Emission of Greenhouse Gases from the Use of Transportation Fuels and Electricity. Emissions of methane, nitrous oxide, carbon monoxide, and other greenhouse gases are discussed. Sources of emission including vehicles, natural gas operations, oil production, coal mines, and power plants are covered. The various energy industries are examined in terms of greenhouse gas production and emissions. Those industries include electricity generation, transport of goods via trains, trucks, ships and pipelines, coal, natural gas and natural gas liquids, petroleum, nuclear energy, and biofuels.

  18. Emission Rates of Multiple Air Pollutants Generated from Chinese Residential Cooking.

    Science.gov (United States)

    Chen, Chen; Zhao, Yuejing; Zhao, Bin

    2018-02-06

    Household air pollution generated from cooking is severe, especially for Chinese-style cooking. We measured the emission rates of multiple air pollutants including fine particles (PM 2.5 ), ultrafine particles (UFPs), and volatile organic compounds (VOCs, including formaldehyde, benzene, and toluene) that were generated from typical Chinese cooking in a residential kitchen. The experiment was designed through five-factor and five-level orthogonal testing. The five key factors were cooking method, ingredient weight, type of meat, type of oil, and meat/vegetable ratio. The measured emission rates (mean value ± standard deviation) of PM 2.5 , UFPs, formaldehyde, total volatile organic compounds (TVOCs), benzene, and toluene were 2.056 ± 3.034 mg/min, 9.102 ± 6.909 × 10 12 #/min, 1.273 ± 0.736 mg/min, 1.349 ± 1.376 mg/min, 0.074 ± 0.039 mg/min, and 0.004 ± 0.004 mg/min. Cooking method was the most influencing factor for the emission rates of PM 2.5 , UFPs, formaldehyde, TVOCs, and benzene but not for toluene. Meanwhile, the emission rate of PM 2.5 was also significantly influenced by ingredient weight, type of meat, and meat/vegetable ratio. Exhausting the range hood decreased the emission rates by approximately 58%, with a corresponding air change rate of 21.38/h for the kitchen room.

  19. Heat-induced electron emission in paraelectric phase of triglycine sulfate heated with great rate

    CERN Document Server

    Sidorkin, A A; Rogazinskaya, O V; Milovidova, S D

    2002-01-01

    One recorded experimentally heat-induced electron emission in ferroelectric triglycine sulfate (TGS) crystal within temperature range exceeding the Curie point by 10-15 K. One studied cases of q = dT/dt various rates of linear heating of specimens of TGS nominally pure crystal and TGS crystal with chromium impurity. Increase of heating rate is shown to result in increase of emission current density within the whole investigated range of temperatures. Temperature of emission occurrence depends on q rate negligibly. At the same time, temperature of emission disappearance monotonically increases with q growth. At q below 1 K/min it is localized below the Curie point. At q = 4-5 K/min the mentioned temperature reaches 60-65 deg C. In TGS crystal with chromium impurity the temperature of emission occurrence is close to the case of pure TGS. In this case, the range of emission drawing in paraphase here is by about 2 times narrower in contrast to the case of pure TGS heated with the same rate

  20. Differential neutrino rates and emissivities from the plasma process in astrophysical systems

    International Nuclear Information System (INIS)

    Ratkovic, Sasa; Iyer Dutta, Sharada; Prakash, Madappa

    2003-01-01

    The differential rates and emissivities of neutrino pairs from an equilibrium plasma are calculated for the wide range of density and temperature encountered in astrophysical systems. New analytical expressions are derived for the differential emissivities which yield total emissivities in full agreement with those previously calculated. The photon and plasmon pair production and absorption kernels in the source term of the Boltzmann equation for neutrino transport are provided. The appropriate Legendre coefficients of these kernels, in forms suitable for multi-group flux-limited diffusion schemes are also computed

  1. Characterization of strain rate sensitivity and activation volume using the indentation relaxation test

    International Nuclear Information System (INIS)

    Xu Baoxing; Chen Xi; Yue Zhufeng

    2010-01-01

    We present the possibility of extracting the strain rate sensitivity, activation volume and Helmholtz free energy (for dislocation activation) using just one indentation stress relaxation test, and the approach is demonstrated with polycrystalline copper. The Helmholtz free energy measured from indentation relaxation agrees well with that from the conventional compression relaxation test, which validates the proposed approach. From the indentation relaxation test, the measured indentation strain rate sensitivity exponent is found to be slightly larger, and the indentation activation volume much smaller, than their counterparts from the compression test. The results indicate the involvement of multiple dislocation mechanisms in the indentation test.

  2. Variations of comoving volume and their effects on the star formation rate density

    Science.gov (United States)

    Kim, Sungeun; Physics and Astronomy, Sejong University, Seoul, Korea (the Republic of).

    2018-01-01

    To build a comprehensive picture of star formation in the universe, we havedeveloped an application to calculate the comoving volume at a specific redshift and visualize the changes of spaceand time. The application is based on the star formation rates of about a few thousands of galaxies and their redshiftvalues. Three dimensional modeling of these galaxies using the redshift, comoving volume, and star formation ratesas input data allows calculation of the star formation rate density corresponding to the redshift. This work issupported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP)(no. 2017037333).

  3. Volume doubling time and growth rate of renal cell carcinoma determined by helical CT: a single-institution experience

    International Nuclear Information System (INIS)

    Lee, Ji Young; Kim, Chan Kyo; Choi, Dongil; Park, Byung Kwan

    2008-01-01

    The purpose of this study was to retrospectively evaluate the volume doubling time (VDT) and growth rate of renal cell carcinomas (RCC) on a serial computed tomography (CT) scan. Thirty pathologically proven RCCs were reviewed with helical CT. Each tumor underwent at least two CT scans. Tumor volume was determined using an area measuring tool and the summation-of-areas technique. Growth rate was evaluated in terms of diameter and volume changes. VDT and volume growth rate were compared in relation to several factors (initial diameter, initial volume, diameter growth rate, volume growth rate, tumor grade, tumor subtype, sex or age). Mean VDT of RCCs was 505 days. Mean diameter and volume growth rate were 0.59 cm/year and 19.1 cm 3 /year, respectively. For volume and diameter growth rate, tumors ≤4 cm showed lower rates than those >4 cm (P 0.05). Volume growth rate was moderately to strongly positively correlated with initial diameter, initial volume and diameter growth rate (P < 0.05). In conclusion, small RCCs grew at a slow rate both diametrically and volumetrically. More accurate assessment of tumor growth rate and VDT may be helpful to understand the natural history of RCC. (orig.)

  4. Fugitive hydrocarbon emissions from pacific OCS facilities. Volume 1. Final report

    International Nuclear Information System (INIS)

    1992-01-01

    In January 1989, the Minerals Management Service (MMS) conducted a study using the latest approved methods for emission screening and sampling solely on Outer Continental Shelf (OCS) oil and gas platforms in the Santa Barbara Channel in order to determine platform emission rates more representative of that region. The study was designed and reviewed throughout its conduct by a Quality Review Board (QRB) composed of air resource agencies and industry. Representatives from the Tri-county Air Pollution Control Districts and the MMS actively participated at these meetings. Some participants expressed concerns about some of the methods used and the study results. ABB's thorough responses to these questions and comments were submitted to all reviewers before the printing of the final report, and are contained in appendices of the study final report now available to the public. The results of the MMS study show that the average emission factors for the Pacific OCS oil and gas facilities measured in 1989 are 3.5 times lower than those Pacific OCS facilities sampled in the 1979 API/Rockwell study, and 7.8 times lower than the Gulf of Mexico OCS facilities sampled in the same 1979 study. Efforts to determine the quantitative effect of inspection and maintenance programs on controlling emissions were inconclusive

  5. Automatic delineation of functional volumes in emission tomography for oncology applications

    International Nuclear Information System (INIS)

    Hatt, M.

    2008-12-01

    One of the main factors of error for semi-quantitative analysis in positron emission tomography (PET) imaging for diagnosis and patient follow up, as well as new flourishing applications like image guided radiotherapy, is the methodology used to define the volumes of interest in the functional images. This is explained by poor image quality in emission tomography resulting from noise and partial volume effects induced blurring, as well as the variability of acquisition protocols, scanner models and image reconstruction procedures. The large number of proposed methodologies for the definition of a PET volume of interest does not help either. The majority of such proposed approaches are based on deterministic binary thresholding that are not robust to contrast variation and noise. In addition, these methodologies are usually unable to correctly handle heterogeneous uptake inside tumours. The objective of this thesis is to develop an automatic, robust, accurate and reproducible 3D image segmentation approach for the functional volumes determination of tumours of all sizes and shapes, and whose activity distribution may be strongly heterogeneous. The approach we have developed is based on a statistical image segmentation framework, combined with a fuzzy measure, which allows to take into account both noisy and blurry properties of nuclear medicine images. It uses a stochastic iterative parameters estimation and a locally adaptive model of the voxel and its neighbours for the estimation and segmentation. The developed approaches have been evaluated using a large array of datasets, comprising both simulated and real acquisitions of phantoms and tumours. The results obtained on phantom acquisitions allowed to validate the accuracy of the segmentation with respect to the size of considered structures, down to 13 mm in diameter (about twice the spatial resolution of a typical PET scanner), as well as its robustness with respect to noise, contrast variation, acquisition

  6. Value of volume measurements in evaluating abdominal aortic aneurysms growth rate and need for surgical treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kontopodis, Nikolaos, E-mail: kontopodisn@yahoo.gr [Department of Vascular Surgery, University of Crete Medical School, Heraklion (Greece); Metaxa, Eleni, E-mail: emmetaxa@gmail.com [Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion, Crete (Greece); Papaharilaou, Yannis, E-mail: yannisp@iacm.forth.gr [Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion, Crete (Greece); Georgakarakos, Efstratios, E-mail: efstratiosgeorg@gmail.com [Vascular Surgery Department, “Demokritus” University of Thrace Medical School, Alexandroupolis (Greece); Tsetis, Dimitris, E-mail: tsetis@med.uoc.gr [Interventional Radiology Unit, Department of Radiology, University of Crete Medical School, Heraklion, Crete (Greece); Ioannou, Christos V., E-mail: ioannou@med.uoc.gr [Department of Vascular Surgery, University of Crete Medical School, Heraklion (Greece)

    2014-07-15

    Purpose: To examine whether indices other than the traditionally used abdominal aortic aneurysm (AAA) maximum diameter, such as AAA volume, intraluminal thrombus (ILT) thickness and ILT volume, may be superior to evaluate aneurismal enlargement. Materials and methods: Thirty-four small AAAs (initially presenting a maximum diameter <5.5 cm which is the threshold for surgical repair) with an initial and a follow-up CT were examined. Median increase and percentile annual change of these variables was calculated. Correlation between growth rates as determined by the new indices under evaluation and those of maximum diameter were assessed. AAAs were divided according to outcome (surveillance vs. elective repair after follow-up which is based on the maximum diameter criterion) and according to growth rate (high vs. low) based on four indices. Contingency between groups of high/low growth rate regarding each of the four indices on one hand and those regarding need for surgical repair on the other was assessed. Results: A strong correlation between growth rates of maximum diameter and those of AAA and ILT volumes could be established. Evaluation of contingency between groups of outcome and those of growth rate revealed significant associations only for AAA and ILT volumes. Subsequently AAAs with a rapid volumetric increase over time had a likelihood ratio of 10 to be operated compared to those with a slower enlargement. Regarding increase of maximum diameter, likelihood ratio between AAAs with rapid and those with slow expansion was only 3. Conclusion: Growth rate of aneurysms regarding 3Dimensional indices of AAA and ILT volumes is significantly associated with the need for surgical intervention while the same does not hold for growth rates determined by 2Dimensional indices of maximum diameter and ILT thickness.

  7. Value of volume measurements in evaluating abdominal aortic aneurysms growth rate and need for surgical treatment

    International Nuclear Information System (INIS)

    Kontopodis, Nikolaos; Metaxa, Eleni; Papaharilaou, Yannis; Georgakarakos, Efstratios; Tsetis, Dimitris; Ioannou, Christos V.

    2014-01-01

    Purpose: To examine whether indices other than the traditionally used abdominal aortic aneurysm (AAA) maximum diameter, such as AAA volume, intraluminal thrombus (ILT) thickness and ILT volume, may be superior to evaluate aneurismal enlargement. Materials and methods: Thirty-four small AAAs (initially presenting a maximum diameter <5.5 cm which is the threshold for surgical repair) with an initial and a follow-up CT were examined. Median increase and percentile annual change of these variables was calculated. Correlation between growth rates as determined by the new indices under evaluation and those of maximum diameter were assessed. AAAs were divided according to outcome (surveillance vs. elective repair after follow-up which is based on the maximum diameter criterion) and according to growth rate (high vs. low) based on four indices. Contingency between groups of high/low growth rate regarding each of the four indices on one hand and those regarding need for surgical repair on the other was assessed. Results: A strong correlation between growth rates of maximum diameter and those of AAA and ILT volumes could be established. Evaluation of contingency between groups of outcome and those of growth rate revealed significant associations only for AAA and ILT volumes. Subsequently AAAs with a rapid volumetric increase over time had a likelihood ratio of 10 to be operated compared to those with a slower enlargement. Regarding increase of maximum diameter, likelihood ratio between AAAs with rapid and those with slow expansion was only 3. Conclusion: Growth rate of aneurysms regarding 3Dimensional indices of AAA and ILT volumes is significantly associated with the need for surgical intervention while the same does not hold for growth rates determined by 2Dimensional indices of maximum diameter and ILT thickness

  8. Air/Superfund National Technical Guidance Study Series. Data Base of emission-rate-measurement projects. Technical note

    Energy Technology Data Exchange (ETDEWEB)

    Eklund, B.; Petrinec, C.; Ranum, D.; Howlett, L.

    1991-06-01

    A compilation and evaluation of Volatile Organic Compound (VOC) emission rate data was performed. The three primary objectives were (1) to determine typical averages and ranges of emissions for various types of sources; (2) to determine the degree of correlation between emission rate results from different sampling methods; and (3) to examine the effects of different variables on measured emission rates. Emission rate data are presented for 33 studies covering 13 types of emission sources. The sources include landfills, surface impoundments, waste water treatment systems, leaking underground storage tanks, soil piles and landfarms. The emission rate data were obtained by using the Emission Isolation Flux Chamber, Downhole Emissions Isolation Flux Chamber, the Concentration Profile method and the Transect method. For each source, the total non-methane hydrocarbon and benzene emission rates are reported along with three other compounds that had the highest emission rate. Source concentration data (e.g. concentration in soil or waste water) are also reported for comparison to the measured emission rates.

  9. Changes in extracellular muscle volume affect heart rate and blood pressure responses to static exercise

    Science.gov (United States)

    Baum, K.; Essfeld, D.; Stegemann, J.

    To investigate the effect of μg-induced peripheral extracellular fluid reductions on heart rate and blood pressure during isometric exercise, six healthy male subjects performed three calf ergometer test with different extracellular volumes of working muscles. In all tests, body positions during exercise were identical (supine with the knee joint flexed to 900). After a pre-exercise period of 25 min, during which calf volumes were manipulated, subjects had to counteract an external force of 180 N for 5 min. During the pre-exercise period three different protocols were applied. Test A: Subjects rested in the exercise position; test B: Body position was the same as in A but calf volume was increased by venous congestion (cuffs inflated to 80 mm Hg); test C: Calf volumes were decreased by a negative hydrostatic pressure (calves about 40 cm above heart level with the subjects supine). To clamp the changed calf volumes in tests B and C, cuffs were inflated to 300 mm Hg 5 min before the onset of exercise. This occlusion was maintained until termination of exercise. Compared to tests A and B, the reduced volume of test C led to significant increases in heart rate and blood pressure during exercise. Oxygen uptake did not exceed resting levels in B and C until cuffs were deflated, indicating that exclusively calf muscles contributed to the neurogenic peripheral drive. It is concluded that changes in extracellular muscle volume have to be taken into account when comparing heart rate and blood pressure during lg- and μg- exercise.

  10. Quantified measurement of brain blood volume: comparative evaluations between the single photon emission computer tomography and the positron computer tomography

    International Nuclear Information System (INIS)

    Bouvard, G.; Fernandez, Y.; Petit-Taboue, M.C.; Derlon, J.M.; Travere, J.M.; Le Poec, C.

    1991-01-01

    The quantified measurement of cerebral blood volume is interesting for the brain blood circulation studies. This measurement is often used in positron computed tomography. It's more difficult in single photon emission computed tomography: there are physical problems with the limited resolution of the detector, the Compton effect and the photon attenuation. The objectif of this study is to compare the results between these two techniques. The quantified measurement of brain blood volume is possible with the single photon emission computer tomogragry. However, there is a loss of contrast [fr

  11. Air pollutant emission rates for sources at the Davis Canyon Repository site

    International Nuclear Information System (INIS)

    1985-11-01

    This document summarizes the air-quality source terms used for the Davis Canyon, Utah environmental assessment report and explains their derivation. The engineering data supporting these source terms appear as appendixes to the report and include summary equipment lists for the repository (December, 1984) and detailed equipment lists for the exploratory shaft (June and July, 1985). Although substantial work has been performed in establishing the current repository design, a greater effort will be required for the final design. Consequently, the repository emission rates presented here should be considered as preliminary estimates. Another set of air pollutant emission rates will be calculated after design data are more firmly established. 19 refs., 18 tabs

  12. Air pollutant emission rates for sources at the Deaf Smith County repository site

    International Nuclear Information System (INIS)

    1985-11-01

    This document summarizes the air-quality source terms used for the Deaf Smith County, Texas environmental assessment report and explains their derivation. The engineering data supporting these source terms appear as appendixes to this report and include summary equipment lists for the repository and detailed equipment lists for the exploratory shaft. Although substantial work has been performed in establishing the current repository design, a greater effort will be required for the final design. Consequently, the repository emission rates presented here should be considered as preliminary estimates. Another set of air pollution emission rates will be calculated after design data are more firmly established. 18 refs., 15 tabs

  13. Cavity-enhanced spontaneous emission rates for rhodamine 6-G in levitated microdroplets

    International Nuclear Information System (INIS)

    Barnes, M.D.; Whitten, W.B.; Ramsey, J.M.; Arnold, S.

    1992-01-01

    Fluorescence decay kinetics of Rhodamine 6-G molecules in levitated glycerol microdroplets (4--20 microns in diameter) have been investigated to determine the effects of spherical cavity resonances on spontaneous emission rates. For droplet diameters greater than 10 microns, the fluorescence lifetime is essentially the same as in bulk glycerol. As the droplet diameter is decreased below 10 microns, bi-exponential decay behavior is observed with a slow component whose rate is similar to bulk glycerol, and a fast component whose rate is as much as a factor of 10 larger than the bulk decay rate. This fast component is attributed to cavity enhancement of the spontaneous emission rate and, within the weak coupling approximation, a value for the homogeneous linewidth at room temperature can be estimated from the fluorescence lifetime data

  14. Brain metabolism in autism. Resting cerebral glucose utilization rates as measured with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rumsey, J.M.; Duara, R.; Grady, C.; Rapoport, J.L.; Margolin, R.A.; Rapoport, S.I.; Cutler, N.R.

    1985-05-01

    The cerebral metabolic rate for glucose was studied in ten men (mean age = 26 years) with well-documented histories of infantile autism and in 15 age-matched normal male controls using positron emission tomography and (F-18) 2-fluoro-2-deoxy-D-glucose. Positron emission tomography was completed during rest, with reduced visual and auditory stimulation. While the autistic group as a whole showed significantly elevated glucose utilization in widespread regions of the brain, there was considerable overlap between the two groups. No brain region showed a reduced metabolic rate in the autistic group. Significantly more autistic, as compared with control, subjects showed extreme relative metabolic rates (ratios of regional metabolic rates to whole brain rates and asymmetries) in one or more brain regions.

  15. Brain metabolism in autism. Resting cerebral glucose utilization rates as measured with positron emission tomography

    International Nuclear Information System (INIS)

    Rumsey, J.M.; Duara, R.; Grady, C.; Rapoport, J.L.; Margolin, R.A.; Rapoport, S.I.; Cutler, N.R.

    1985-01-01

    The cerebral metabolic rate for glucose was studied in ten men (mean age = 26 years) with well-documented histories of infantile autism and in 15 age-matched normal male controls using positron emission tomography and (F-18) 2-fluoro-2-deoxy-D-glucose. Positron emission tomography was completed during rest, with reduced visual and auditory stimulation. While the autistic group as a whole showed significantly elevated glucose utilization in widespread regions of the brain, there was considerable overlap between the two groups. No brain region showed a reduced metabolic rate in the autistic group. Significantly more autistic, as compared with control, subjects showed extreme relative metabolic rates (ratios of regional metabolic rates to whole brain rates and asymmetries) in one or more brain regions

  16. A Gaussian mixture model for definition of lung tumor volumes in positron emission tomography

    International Nuclear Information System (INIS)

    Aristophanous, Michalis; Penney, Bill C.; Martel, Mary K.; Pelizzari, Charles A.

    2007-01-01

    The increased interest in 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in radiation treatment planning in the past five years necessitated the independent and accurate segmentation of gross tumor volume (GTV) from FDG-PET scans. In some studies the radiation oncologist contours the GTV based on a computed tomography scan, while incorporating pertinent data from the PET images. Alternatively, a simple threshold, typically 40% of the maximum intensity, has been employed to differentiate tumor from normal tissue, while other researchers have developed algorithms to aid the PET based GTV definition. None of these methods, however, results in reliable PET tumor segmentation that can be used for more sophisticated treatment plans. For this reason, we developed a Gaussian mixture model (GMM) based segmentation technique on selected PET tumor regions from non-small cell lung cancer patients. The purpose of this study was to investigate the feasibility of using a GMM-based tumor volume definition in a robust, reliable and reproducible way. A GMM relies on the idea that any distribution, in our case a distribution of image intensities, can be expressed as a mixture of Gaussian densities representing different classes. According to our implementation, each class belongs to one of three regions in the image; the background (B), the uncertain (U) and the target (T), and from these regions we can obtain the tumor volume. User interaction in the implementation is required, but is limited to the initialization of the model parameters and the selection of an ''analysis region'' to which the modeling is restricted. The segmentation was developed on three and tested on another four clinical cases to ensure robustness against differences observed in the clinic. It also compared favorably with thresholding at 40% of the maximum intensity and a threshold determination function based on tumor to background image intensities proposed in a recent paper. The parts of the

  17. Assessment of high to low frequency variations of isoprene emission rates using a neural network approach

    Science.gov (United States)

    Boissard, C.; Chervier, F.; Dutot, A. L.

    2007-08-01

    Using a statistical approach based on artificial neural networks, an emission algorithm (ISO_LF) accounting for high (instantaneous) to low (seasonal) frequency variations was developed for isoprene. ISO_LF was optimised using an isoprene emission data base (ISO-DB) specifically designed for this work. ISO-DB consists of 1321 emission rates collected in the literature, together with 34 environmental variables, measured or assessed using NCDC (National Climatic Data Center) or NCEP (National Centers for Environmental Predictions) meteorological databases. ISO-DB covers a large variety of emitters (25 species) and environmental conditions (10° S to 60° N). When only instantaneous environmental regressors (air temperature and photosynthetic active radiation, PAR) were used, a maximum of 60% of the overall isoprene variability was assessed and the highest emissions were underestimated. Considering a total of 9 high (instantaneous) to low (up to 3 weeks) frequency regressors, ISO_LF accounts for up to 91% of the isoprene emission variability, whatever the emission range, species or climate. Diurnal and seasonal variations are correctly reproduced for textit{Ulex europaeus} with a maximum factor of discrepancy of 4. ISO-LF was found to be mainly sensitive to air temperature cumulated over 3 weeks T21 and to instantaneous light L0 and air temperature T0 variations. T21, T0 and L0 only accounts for 76% of the overall variability. The use of ISO-LF for non stored monoterpene emissions was shown to give poor results.

  18. Tyrosine positron emission tomography and protein synthesis rate in pituitary adenoma: Different effects of surgery and radiation therapy

    International Nuclear Information System (INIS)

    Bergh, Alfons C.M. van den; Pruim, Jan; Links, Thera P.; Vliet, Anton M. van der; Sluiter, Wim; Wolffenbuttel, Bruce H.R.; Langendijk, Johannes A.; Hoving, Eelco W.; Dullaart, Robin P.F.

    2011-01-01

    Introduction: Positron emission tomography (PET) using amino acid tracers is able to establish biochemical tumour characterization in vivo. The use of PET in the follow-up of non-functioning pituitary adenomas (NFA) and growth hormone producing pituitary adenomas (GHA) after surgery and radiation treatment is not yet clear. Methods: To determine the value of PET before and after transsphenoidal neurosurgery in NFA and GHA, we investigated 12 patients with pituitary adenoma (9 NFA and 3 GHA) before and 4 months after surgery with magnetic resonance imaging (MRI) and tyrosine PET (TYR-PET). Three years after radiation therapy TYR-PET was used to document residual activity in 6 of these patients (4 NFA- and 2 GHA). Tumour size was quantified by computerized MRI measurements. In TYR-PET, tumour activity was assessed by computerized measurements of the hot spot and by determination of protein synthesis rate (PSR). Results: In response to surgery, MRI showed a median tumour volume reduction of 58% (P 0.30). After radiation therapy the MRI-volumes of the residual pituitary adenomas did not change but the volume of the hot spot on TYR-PET-imaging was reduced by 58% (P = 0.02), and PSR decreased in 5 of 6 patients (P = 0.12). Conclusion: Amino acid PET tumour activity is reduced parallel with MRI volume changes after surgery. The decrease in TYR-PET activity after radiation therapy, despite unaltered MRI tumour volume, supports the concept that it is possible to follow biological tumour activity with this technique. The diagnostic merit of this tracer technique, predicting pituitary adenoma re-growth, needs to be validated in a large prospective study.

  19. EFFECTS OF BURN RATE, WOOD SPECIES, MOISTURE CONTENT AND WEIGHT OF WOOD LOADED ON WOODSTOVE EMISSIONS

    Science.gov (United States)

    The report gives results of tests of four woodstove operating parameters (burn rate, wood moisture, wood load, and wood species) at two levels each using a half factorial experimental test design to determine statistically significant effects on the emission components CO, CO2, p...

  20. Fine and Coarse Particle Mass Concentrations and Emission Rates in the Workplace of a Detergent Industry

    Czech Academy of Sciences Publication Activity Database

    Glytsos, T.; Ondráček, Jakub; Džumbová, Lucie; Eleftheriadis, K.; Lazaridis, M.

    2014-01-01

    Roč. 23, č. 6 (2014), s. 881-889 ISSN 1420-326X Institutional support: RVO:67985858 Keywords : emission rates * PM 10 * PM2,5 * mass balance model Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.225, year: 2014

  1. Influence of satellite-derived photolysis rates and NOx emissions on Texas ozone modeling

    Science.gov (United States)

    Tang, W.; Cohan, D. S.; Pour-Biazar, A.; Lamsal, L. N.; White, A. T.; Xiao, X.; Zhou, W.; Henderson, B. H.; Lash, B. F.

    2015-02-01

    Uncertain photolysis rates and emission inventory impair the accuracy of state-level ozone (O3) regulatory modeling. Past studies have separately used satellite-observed clouds to correct the model-predicted photolysis rates, or satellite-constrained top-down NOx emissions to identify and reduce uncertainties in bottom-up NOx emissions. However, the joint application of multiple satellite-derived model inputs to improve O3 state implementation plan (SIP) modeling has rarely been explored. In this study, Geostationary Operational Environmental Satellite (GOES) observations of clouds are applied to derive the photolysis rates, replacing those used in Texas SIP modeling. This changes modeled O3 concentrations by up to 80 ppb and improves O3 simulations by reducing modeled normalized mean bias (NMB) and normalized mean error (NME) by up to 0.1. A sector-based discrete Kalman filter (DKF) inversion approach is incorporated with the Comprehensive Air Quality Model with extensions (CAMx)-decoupled direct method (DDM) model to adjust Texas NOx emissions using a high-resolution Ozone Monitoring Instrument (OMI) NO2 product. The discrepancy between OMI and CAMx NO2 vertical column densities (VCDs) is further reduced by increasing modeled NOx lifetime and adding an artificial amount of NO2 in the upper troposphere. The region-based DKF inversion suggests increasing NOx emissions by 10-50% in most regions, deteriorating the model performance in predicting ground NO2 and O3, while the sector-based DKF inversion tends to scale down area and nonroad NOx emissions by 50%, leading to a 2-5 ppb decrease in ground 8 h O3 predictions. Model performance in simulating ground NO2 and O3 are improved using sector-based inversion-constrained NOx emissions, with 0.25 and 0.04 reductions in NMBs and 0.13 and 0.04 reductions in NMEs, respectively. Using both GOES-derived photolysis rates and OMI-constrained NOx emissions together reduces modeled NMB and NME by 0.05, increases the model

  2. Study of Acoustic Emission and Mechanical Characteristics of Coal Samples under Different Loading Rates

    Directory of Open Access Journals (Sweden)

    Huamin Li

    2015-01-01

    Full Text Available To study the effect of loading rate on mechanical properties and acoustic emission characteristics of coal samples, collected from Sanjiaohe Colliery, the uniaxial compression tests are carried out under various levels of loading rates, including 0.001 mm/s, 0.002 mm/s, and 0.005 mm/s, respectively, using AE-win E1.86 acoustic emission instrument and RMT-150C rock mechanics test system. The results indicate that the loading rate has a strong impact on peak stress and peak strain of coal samples, but the effect of loading rate on elasticity modulus of coal samples is relatively small. When the loading rate increases from 0.001 mm/s to 0.002 mm/s, the peak stress increases from 22.67 MPa to 24.99 MPa, the incremental percentage is 10.23%, and under the same condition the peak strain increases from 0.006191 to 0.007411 and the incremental percentage is 19.71%. Similarly, when the loading rate increases from 0.002 mm/s to 0.005 mm/s, the peak stress increases from 24.99 MPa to 28.01 MPa, the incremental percentage is 12.08%, the peak strain increases from 0.007411 to 0.008203, and the incremental percentage is 10.69%. The relationship between acoustic emission and loading rate presents a positive correlation, and the negative correlation relation has been determined between acoustic emission cumulative counts and loading rate during the rupture process of coal samples.

  3. In-situ virtual metrology for the silicon-dioxide etch rate by using optical emission spectroscopy data

    International Nuclear Information System (INIS)

    Kim, Boomsoo; Hong, Sangjeen

    2014-01-01

    As a useful tool for process control in a high volume semiconductor manufacturing environment, virtual metrology for the etch rate in a plasma etch process is investigated using optical emission spectroscopy (OES) data. Virtual metrology is a surrogate measurement taken from the process instead of from direct measurement, and it can provide in-situ metrology of a wafer's geometry from a predictive model. A statistical regression model that correlates the selected wavelengths of the optical emission spectra to the etch rate is established using the OES data collected over 20 experimental runs. In addition, an argon actinometry study is employed to quantify the OES data, and it provides valuable insight into the analysis of the OES data. The established virtual metrology model is further verified with an additional 20 runs of data. As a result, the virtual metrology model with both process recipe tool data and in-situ data shows higher prediction accuracy by as much as 56% compared with either the process recipe tool data or the in-situ data alone.

  4. Optimal carbon emissions trajectories when damages depend on the rate or level of global warming

    International Nuclear Information System (INIS)

    Peck, S.C.; Teisberg, T.J.

    1994-01-01

    The authors extend earlier work with the Carbon Emissions Trajectory Assessment model (CETA) to consider a number of issues relating to the nature of optimal carbon emissions trajectories. They first explore model results when warming costs are associated with the rate of temperature rise, rather than with its level, as in earlier work. It is found that optimal trajectories are more strongly affected by the degree of non-linearity in the warming cost function than by whether the cost function is driven by the warming level or the warming rate. The authors briefly explore the implications of simple uncertainty and risk aversion for optimal emissions trajectories to be somewhat lower, but that the effect is not noticeable in the near term and not dramatic in the long term; the long term effect on the shadow price of carbon is more marked, however. Finally, they experiment with scaling up the warming cost functions until optimal policies are approximately the same as a policy of stabilising emissions at the 1990 level. Based on the results of this experiment, it is concluded that damages would have to be very high to justify anything like a stabilization policy; and even in this case, a policy allowing intertemporal variation in emissions would be better. 18 refs., 15 figs

  5. Study of emission of a volume nanosecond discharge plasma in xenon, krypton and argon at high pressures

    International Nuclear Information System (INIS)

    Baksht, E Kh; Lomaev, Mikhail I; Rybka, D V; Tarasenko, Viktor F

    2006-01-01

    The emission properties of a volume nanosecond discharge plasma produced in xenon, krypton and argon at high pressures in a discharge gap with a cathode having a small radius of curvature are studied. Spectra in the range 120-850 nm and amplitude-time characteristics of xenon emission at different regimes and excitation techniques are recorded and analysed. It is shown that upon excitation of the volume discharge initiated by a beam of avalanche electrons, at least 90% of the energy in the spectral range 120-850 nm is emitted by xenon dimers. For xenon at a pressure of 1.2 atm, ∼45 mJ of the spontaneous emission energy was obtained in the full solid angle in a pulse with the full width at half-maximum ∼130 ns. (laser applications and other topics in quantum electronics)

  6. Accurate Automatic Delineation of Heterogeneous Functional Volumes in Positron Emission Tomography for Oncology Applications

    International Nuclear Information System (INIS)

    Hatt, Mathieu; Cheze le Rest, Catherine; Descourt, Patrice; Dekker, Andre; De Ruysscher, Dirk; Oellers, Michel; Lambin, Philippe; Pradier, Olivier; Visvikis, Dimitris

    2010-01-01

    Purpose: Accurate contouring of positron emission tomography (PET) functional volumes is now considered crucial in image-guided radiotherapy and other oncology applications because the use of functional imaging allows for biological target definition. In addition, the definition of variable uptake regions within the tumor itself may facilitate dose painting for dosimetry optimization. Methods and Materials: Current state-of-the-art algorithms for functional volume segmentation use adaptive thresholding. We developed an approach called fuzzy locally adaptive Bayesian (FLAB), validated on homogeneous objects, and then improved it by allowing the use of up to three tumor classes for the delineation of inhomogeneous tumors (3-FLAB). Simulated and real tumors with histology data containing homogeneous and heterogeneous activity distributions were used to assess the algorithm's accuracy. Results: The new 3-FLAB algorithm is able to extract the overall tumor from the background tissues and delineate variable uptake regions within the tumors, with higher accuracy and robustness compared with adaptive threshold (T bckg ) and fuzzy C-means (FCM). 3-FLAB performed with a mean classification error of less than 9% ± 8% on the simulated tumors, whereas binary-only implementation led to errors of 15% ± 11%. T bckg and FCM led to mean errors of 20% ± 12% and 17% ± 14%, respectively. 3-FLAB also led to more robust estimation of the maximum diameters of tumors with histology measurements, with bckg and FCM lead to 10%, 12%, and 13%, respectively. Conclusion: These encouraging results warrant further investigation in future studies that will investigate the impact of 3-FLAB in radiotherapy treatment planning, diagnosis, and therapy response evaluation.

  7. A multiresolution image based approach for correction of partial volume effects in emission tomography

    International Nuclear Information System (INIS)

    Boussion, N; Hatt, M; Lamare, F; Bizais, Y; Turzo, A; Rest, C Cheze-Le; Visvikis, D

    2006-01-01

    Partial volume effects (PVEs) are consequences of the limited spatial resolution in emission tomography. They lead to a loss of signal in tissues of size similar to the point spread function and induce activity spillover between regions. Although PVE can be corrected for by using algorithms that provide the correct radioactivity concentration in a series of regions of interest (ROIs), so far little attention has been given to the possibility of creating improved images as a result of PVE correction. Potential advantages of PVE-corrected images include the ability to accurately delineate functional volumes as well as improving tumour-to-background ratio, resulting in an associated improvement in the analysis of response to therapy studies and diagnostic examinations, respectively. The objective of our study was therefore to develop a methodology for PVE correction not only to enable the accurate recuperation of activity concentrations, but also to generate PVE-corrected images. In the multiresolution analysis that we define here, details of a high-resolution image H (MRI or CT) are extracted, transformed and integrated in a low-resolution image L (PET or SPECT). A discrete wavelet transform of both H and L images is performed by using the 'a trous' algorithm, which allows the spatial frequencies (details, edges, textures) to be obtained easily at a level of resolution common to H and L. A model is then inferred to build the lacking details of L from the high-frequency details in H. The process was successfully tested on synthetic and simulated data, proving the ability to obtain accurately corrected images. Quantitative PVE correction was found to be comparable with a method considered as a reference but limited to ROI analyses. Visual improvement and quantitative correction were also obtained in two examples of clinical images, the first using a combined PET/CT scanner with a lymphoma patient and the second using a FDG brain PET and corresponding T1-weighted MRI in

  8. PETPVC: a toolbox for performing partial volume correction techniques in positron emission tomography

    Science.gov (United States)

    Thomas, Benjamin A.; Cuplov, Vesna; Bousse, Alexandre; Mendes, Adriana; Thielemans, Kris; Hutton, Brian F.; Erlandsson, Kjell

    2016-11-01

    Positron emission tomography (PET) images are degraded by a phenomenon known as the partial volume effect (PVE). Approaches have been developed to reduce PVEs, typically through the utilisation of structural information provided by other imaging modalities such as MRI or CT. These methods, known as partial volume correction (PVC) techniques, reduce PVEs by compensating for the effects of the scanner resolution, thereby improving the quantitative accuracy. The PETPVC toolbox described in this paper comprises a suite of methods, both classic and more recent approaches, for the purposes of applying PVC to PET data. Eight core PVC techniques are available. These core methods can be combined to create a total of 22 different PVC techniques. Simulated brain PET data are used to demonstrate the utility of toolbox in idealised conditions, the effects of applying PVC with mismatched point-spread function (PSF) estimates and the potential of novel hybrid PVC methods to improve the quantification of lesions. All anatomy-based PVC techniques achieve complete recovery of the PET signal in cortical grey matter (GM) when performed in idealised conditions. Applying deconvolution-based approaches results in incomplete recovery due to premature termination of the iterative process. PVC techniques are sensitive to PSF mismatch, causing a bias of up to 16.7% in GM recovery when over-estimating the PSF by 3 mm. The recovery of both GM and a simulated lesion was improved by combining two PVC techniques together. The PETPVC toolbox has been written in C++, supports Windows, Mac and Linux operating systems, is open-source and publicly available.

  9. Pleural liquid clearance rate measured in awake sheep by the volume of dilution method

    International Nuclear Information System (INIS)

    Broaddus, V.C.; Wiener-Kronish, J.P.; Berthiaume, Y.; Staub, N.C.

    1986-01-01

    The authors reported 24h clearance of mock pleural effusions measured terminally in sheep. To measure effusion volume at different times in the same sheep, they injected 111 In-transferrin and measured its dilution. In 5 sheep with effusions of known sizes, the method was accurate to +/-10%. In 5 awake sheep, the authors injected 10 ml/kg of a 1% protein solution via a non-penetrating rib capsule. At 6h, the authors measured the volume by the dilution method and at 24h by direct recovery. The clearance rate in each animal was constant at 2.9-6.0%/h (average 4.8 +/- 1.3%/h). This new method gives a reliable two point clearance rate and requires fewer animals

  10. Assessing Rates of Global Warming Emissions from Port- Fuel Injection and Gasoline Direct Injection Engines in Light-Duty Passenger Vehicles

    Science.gov (United States)

    Short, D.; , D., Vi; Durbin, T.; Karavalakis, G.; Asa-Awuku, A. A.

    2013-12-01

    Passenger vehicles are known emitters of climate warming pollutants. CO2 from automobile emissions are an anthropogenic greenhouse gas (GHG) and a large contributor to global warming. Worldwide, CO2 emissions from passenger vehicles are responsible for 11% of the total CO2 emissions inventory. Black Carbon (BC), another common vehicular emission, may be the second largest contributor to global warming (after CO2). Currently, 52% of BC emissions in the U.S are from the transportation sector, with ~10% originating from passenger vehicles. The share of pollutants from passenger gasoline vehicles is becoming larger due to the reduction of BC from diesel vehicles. Currently, the majority of gasoline passenger vehicles in the United States have port- fuel injection (PFI) engines. Gasoline direct injection (GDI) engines have increased fuel economy compared to the PFI engine. GDI vehicles are predicted to dominate the U.S. passenger vehicle market in the coming years. The method of gasoline injection into the combustion chamber is the primary difference between these two technologies, which can significantly impact primary emissions from light-duty vehicles (LDV). Our study will measure LDV climate warming emissions and assess the impact on climate due to the change in U.S vehicle technologies. Vehicles were tested on a light- duty chassis dynamometer for emissions of CO2, methane (CH4), and BC. These emissions were measured on F3ederal and California transient test cycles and at steady-state speeds. Vehicles used a gasoline blend of 10% by volume ethanol (E10). E10 fuel is now found in 95% of gasoline stations in the U.S. Data is presented from one GDI and one PFI vehicle. The 2012 Kia Optima utilizes GDI technology and has a large market share of the total GDI vehicles produced in the U.S. In addition, The 2012 Toyota Camry, equipped with a PFI engine, was the most popular vehicle model sold in the U.S. in 2012. Methane emissions were ~50% lower for the GDI technology

  11. Process control of high rate microcrystalline silicon based solar cell deposition by optical emission spectroscopy

    International Nuclear Information System (INIS)

    Kilper, T.; Donker, M.N. van den; Carius, R.; Rech, B.; Braeuer, G.; Repmann, T.

    2008-01-01

    Silicon thin-film solar cells based on microcrystalline silicon (μc-Si:H) were prepared in a 30 x 30 cm 2 plasma-enhanced chemical vapor deposition reactor using 13.56 or 40.68 MHz plasma excitation frequency. Plasma emission was recorded by optical emission spectroscopy during μc-Si:H absorber layer deposition at deposition rates between 0.5 and 2.5 nm/s. The time course of SiH * and H β emission indicated strong drifts in the process conditions particularly at low total gas flows. By actively controlling the SiH 4 gas flow, the observed process drifts were successfully suppressed resulting in a more homogeneous i-layer crystallinity along the growth direction. In a deposition regime with efficient usage of the process gas, the μc-Si:H solar cell efficiency was enhanced from 7.9 % up to 8.8 % by applying process control

  12. Effects of air pollutants on the carbon dioxide (CO2) emission rate of human subjects

    DEFF Research Database (Denmark)

    Bako-Biro, Zsolt; Wargocki, Pawel; Wyon, David

    2004-01-01

    Several laboratory studies have shown the negative effects of emissions from typical indoor pollution sources on perceived air quality, SBS symptoms and the performance of office work. The subjects performed typical office tasks at their own pace while they were exposed for several hours to diffe...... to different air quality conditions. A re-analysis of the CO2 measurements obtained in two independent studies showed that human CO2 emission rates were affected by air quality (P......Several laboratory studies have shown the negative effects of emissions from typical indoor pollution sources on perceived air quality, SBS symptoms and the performance of office work. The subjects performed typical office tasks at their own pace while they were exposed for several hours...

  13. Sequential multi-nuclide emission rate estimation method based on gamma dose rate measurement for nuclear emergency management

    International Nuclear Information System (INIS)

    Zhang, Xiaole; Raskob, Wolfgang; Landman, Claudia; Trybushnyi, Dmytro; Li, Yu

    2017-01-01

    Highlights: • Sequentially reconstruct multi-nuclide emission using gamma dose rate measurements. • Incorporate a priori ratio of nuclides into the background error covariance matrix. • Sequentially augment and update the estimation and the background error covariance. • Suppress the generation of negative estimations for the sequential method. • Evaluate the new method with twin experiments based on the JRODOS system. - Abstract: In case of a nuclear accident, the source term is typically not known but extremely important for the assessment of the consequences to the affected population. Therefore the assessment of the potential source term is of uppermost importance for emergency response. A fully sequential method, derived from a regularized weighted least square problem, is proposed to reconstruct the emission and composition of a multiple-nuclide release using gamma dose rate measurement. The a priori nuclide ratios are incorporated into the background error covariance (BEC) matrix, which is dynamically augmented and sequentially updated. The negative estimations in the mathematical algorithm are suppressed by utilizing artificial zero-observations (with large uncertainties) to simultaneously update the state vector and BEC. The method is evaluated by twin experiments based on the JRodos system. The results indicate that the new method successfully reconstructs the emission and its uncertainties. Accurate a priori ratio accelerates the analysis process, which obtains satisfactory results with only limited number of measurements, otherwise it needs more measurements to generate reasonable estimations. The suppression of negative estimation effectively improves the performance, especially for the situation with poor a priori information, where it is more prone to the generation of negative values.

  14. Sequential multi-nuclide emission rate estimation method based on gamma dose rate measurement for nuclear emergency management

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaole, E-mail: zhangxiaole10@outlook.com [Institute for Nuclear and Energy Technologies, Karlsruhe Institute of Technology, Karlsruhe, D-76021 (Germany); Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing, 100084 (China); Raskob, Wolfgang; Landman, Claudia; Trybushnyi, Dmytro; Li, Yu [Institute for Nuclear and Energy Technologies, Karlsruhe Institute of Technology, Karlsruhe, D-76021 (Germany)

    2017-03-05

    Highlights: • Sequentially reconstruct multi-nuclide emission using gamma dose rate measurements. • Incorporate a priori ratio of nuclides into the background error covariance matrix. • Sequentially augment and update the estimation and the background error covariance. • Suppress the generation of negative estimations for the sequential method. • Evaluate the new method with twin experiments based on the JRODOS system. - Abstract: In case of a nuclear accident, the source term is typically not known but extremely important for the assessment of the consequences to the affected population. Therefore the assessment of the potential source term is of uppermost importance for emergency response. A fully sequential method, derived from a regularized weighted least square problem, is proposed to reconstruct the emission and composition of a multiple-nuclide release using gamma dose rate measurement. The a priori nuclide ratios are incorporated into the background error covariance (BEC) matrix, which is dynamically augmented and sequentially updated. The negative estimations in the mathematical algorithm are suppressed by utilizing artificial zero-observations (with large uncertainties) to simultaneously update the state vector and BEC. The method is evaluated by twin experiments based on the JRodos system. The results indicate that the new method successfully reconstructs the emission and its uncertainties. Accurate a priori ratio accelerates the analysis process, which obtains satisfactory results with only limited number of measurements, otherwise it needs more measurements to generate reasonable estimations. The suppression of negative estimation effectively improves the performance, especially for the situation with poor a priori information, where it is more prone to the generation of negative values.

  15. What could have caused pre-industrial biomass burning emissions to exceed current rates?

    Directory of Open Access Journals (Sweden)

    G. R. van der Werf

    2013-01-01

    Full Text Available Recent studies based on trace gas mixing ratios in ice cores and charcoal data indicate that biomass burning emissions over the past millennium exceeded contemporary emissions by up to a factor of 4 for certain time periods. This is surprising because various sources of biomass burning are linked with population density, which has increased over the past centuries. We have analysed how emissions from several landscape biomass burning sources could have fluctuated to yield emissions that are in correspondence with recent results based on ice core mixing ratios of carbon monoxide (CO and its isotopic signature measured at South Pole station (SPO. Based on estimates of contemporary landscape fire emissions and the TM5 chemical transport model driven by present-day atmospheric transport and OH concentrations, we found that CO mixing ratios at SPO are more sensitive to emissions from South America and Australia than from Africa, and are relatively insensitive to emissions from the Northern Hemisphere. We then explored how various landscape biomass burning sources may have varied over the past centuries and what the resulting emissions and corresponding CO mixing ratio at SPO would be, using population density variations to reconstruct sources driven by humans (e.g., fuelwood burning and a new model to relate savanna emissions to changes in fire return times. We found that to match the observed ice core CO data, all savannas in the Southern Hemisphere had to burn annually, or bi-annually in combination with deforestation and slash and burn agriculture exceeding current levels, despite much lower population densities and lack of machinery to aid the deforestation process. While possible, these scenarios are unlikely and in conflict with current literature. However, we do show the large potential for increased emissions from savannas in a pre-industrial world. This is mainly because in the past, fuel beds were probably less fragmented compared to the

  16. Surgical Space Suits Increase Particle and Microbiological Emission Rates in a Simulated Surgical Environment.

    Science.gov (United States)

    Vijaysegaran, Praveen; Knibbs, Luke D; Morawska, Lidia; Crawford, Ross W

    2018-05-01

    The role of space suits in the prevention of orthopedic prosthetic joint infection remains unclear. Recent evidence suggests that space suits may in fact contribute to increased infection rates, with bioaerosol emissions from space suits identified as a potential cause. This study aimed to compare the particle and microbiological emission rates (PER and MER) of space suits and standard surgical clothing. A comparison of emission rates between space suits and standard surgical clothing was performed in a simulated surgical environment during 5 separate experiments. Particle counts were analyzed with 2 separate particle counters capable of detecting particles between 0.1 and 20 μm. An Andersen impactor was used to sample bacteria, with culture counts performed at 24 and 48 hours. Four experiments consistently showed statistically significant increases in both PER and MER when space suits are used compared with standard surgical clothing. One experiment showed inconsistent results, with a trend toward increases in both PER and MER when space suits are used compared with standard surgical clothing. Space suits cause increased PER and MER compared with standard surgical clothing. This finding provides mechanistic evidence to support the increased prosthetic joint infection rates observed in clinical studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Examination of Environmental Factors Influencing the Emission Rates of Semivolatile Organic Compounds

    Directory of Open Access Journals (Sweden)

    Sunwoo Lee

    2018-01-01

    Full Text Available Some types of semivolatile organic compounds (SVOCs that are emitted from plastics used in building materials and household appliances have been associated with health risks, even at low concentrations. It has been reported that di-2-ethylhexyl phthalate (DEHP—one of the most commonly used plasticizers—causes asthma and allergic symptoms in children at home. The amount of emitted DEHP, which is classified as a SVOC, can be measured using a microchamber by the thermal desorption test chamber method. To accurately measure the SVOC emission rates, the relation between SVOC and environmental factors should be clarified. Herein, we examined the effects of the temperature, relative humidity, concentration of airborne particles, and flow field in the microchamber on SVOC emission rates. The flow fields inside the microchamber were analyzed via computational fluid dynamics (CFD. The emission rate of SVOC released from PVC flooring increased under high temperatures and at high concentrations of airborne particles but did not depend on the relative humidity. From an evaluation performed using an index of air change efficiency, such as the air age and the coefficient of air change performance, we found that a fixed air exchange rate of 1.5 h−1 in the microchamber is desirable.

  18. Isoprene emission rates and fluxes measured above a Mediterranean oak ( Quercus pubescens) forest

    Science.gov (United States)

    Simon, V.; Dumergues, L.; Bouchou, P.; Torres, L.; Lopez, A.

    2005-03-01

    The present work, carried out as part of the European fiEld experimentS to COnstrain Models of atmospheric Pollution and Transport of Emissions project (ESCOMPTE), brings a new contribution to the inventory of the main natural hydrocarbons sources that are liable to participate in the production of ozone. The measurement campaign was conducted in Montmeyan, a site close to Marseilles (France), with the aim of quantifying the terpenic emission pattern and the behaviour of Quercus pubescens, an important Mediterranean tree species. Biogenic emissions by Q. pubescens were determined by the enclosure of an intact branch of this tree in a Teflon cuvette. The total monoterpenic emission rates thus recorded were found to reach maximum values ranged between 40 and 350 μg g Dry Weight-1 h -1. Emissions were correlated strongly with leaf temperature and Photosynthetic Active Radiation (PAR). The fluxes were also determined by extrapolating the results of the enclosure method and by using aerodynamic gradient method. They reach around 73 mg m -2 h -1 with the first method and 55 mg m -2 h -1 with the second one. The obtained values fit with a maximal ratio of 2.

  19. Emission rates of sulfur dioxide, trace gases and metals from Mount Erebus, Antartica

    Energy Technology Data Exchange (ETDEWEB)

    Kyle, P.R.; Meeker, K. (New Mexico Institute of Mining and Technology, Socorro (USA)); Finnegan, D. (Los Alamos National Lab., NM (USA))

    1990-11-01

    SO{sub 2} emission rates have been measured annually since 1983 at Mount Erebus, Antarctica by correlation spectrometer (COSPEC V). Following a 4 month period of sustained strombolian activity in late 1984, SO{sub 2} emissions declined from 230 Mg/day in 1983 to 25 Mg/day and then slowly increased from 16 Mg/day in 1985 to 51 Mg/day in 1987. Nine sets of filter packs containing partcle and {sup 7}LiOH treated filters were collected in the plume in 1986 and analyzed by neutron activation. Using the COSPEC data and measured element/S ratios on the filters, emission rates have been determined for trace gases and metals. The authors infer HCl and HF emissions in 1983 to be about 1200 and 500 Mg/day, respectively. Mt Erebus has therefore been an important source of halogens to the Anarctic atmosphere and could be responsible for excess Cl found in Central Antarctica snow.

  20. Measurement of disintegration rates of 60Co volume sources by the sum-peak method

    International Nuclear Information System (INIS)

    Kawano, Takao; Ebihara, Hiroshi

    1991-01-01

    The sum-peak method has been applied to the determination of the disintegration rates of 60 Co volume sources (1.05 x 10 4 Bq, 1.05 x 10 3 Bq and 1.05 x 10 2 Bq, in 100-ml polyethylene bottles) by using a NaI(Tl) detector of a diameter of 50 mm and a height of 50 mm. The experimental results showed that decreasing the disintegration rates resulted in enlarged underestimation in comparison with the true disintegration rates. It was presumed that the underestimations of the disintegration rates determined by the sum-peak method resulted from the overestimations of the areas under the sum peaks caused by the overlap of the area under the Compton scattering of the γ-ray (2614 keV) emitted from a naturally occurring radionuclide 208 Tl under the sum peaks. (author)

  1. 76 FR 21418 - Fiscal Year 2011 Allocation of Additional Tariff-Rate Quota Volume for Raw Cane Sugar and...

    Science.gov (United States)

    2011-04-15

    ...-Rate Quota Volume for Raw Cane Sugar and Reallocation of Unused Fiscal Year 2011 Tariff-Rate Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION: Notice...) for imported raw cane sugar and of country-by-country reallocations of the FY 2011 in-quota quantity...

  2. 77 FR 25012 - Fiscal Year 2012 Allocation of Additional Tariff-Rate Quota Volume for Raw Cane Sugar and...

    Science.gov (United States)

    2012-04-26

    ...-Rate Quota Volume for Raw Cane Sugar and Reallocation of Unused Fiscal Year 2012 Tariff-Rate Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION: Notice...) for imported raw cane sugar and of country-by-country reallocations of the FY 2012 in-quota quantity...

  3. Volume Changes After Stereotactic LINAC Radiotherapy in Vestibular Schwannoma: Control Rate and Growth Patterns

    International Nuclear Information System (INIS)

    Langenberg, Rick van de; Dohmen, Amy J.C.; Bondt, Bert J. de; Nelemans, Patty J.; Baumert, Brigitta G.; Stokroos, Robert J.

    2012-01-01

    Purpose: The purpose of this study was to evaluate the control rate of vestibular schwannomas (VS) after treatment with linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) or radiotherapy (SRT) by using a validated volumetric measuring tool. Volume-based studies on prognosis after LINAC-based SRS or SRT for VS are reported scarcely. In addition, growth patterns and risk factors predicting treatment failure were analyzed. Materials and Methods: Retrospectively, 37 VS patients treated with LINAC based SRS or SRT were analyzed. Baseline and follow-up magnetic resonance imaging scans were analyzed with volume measurements on contrast enhanced T1-weighted magnetic resonance imaging. Absence of intervention after radiotherapy was defined as “no additional intervention group, ” absence of radiological growth was defined as “radiological control group. ” Significant growth was defined as a volume change of 19.7% or more, as calculated in a previous study. Results: The cumulative 4-year probability of no additional intervention was 96.4% ± 0.03; the 4-year radiological control probability was 85.4% ± 0.1). The median follow-up was 40 months. Overall, shrinkage was seen in 65%, stable VS in 22%, and growth in 13%. In 54% of all patients, transient swelling was observed. No prognostic factors were found regarding VS growth. Previous treatment and SRS were associated with transient swelling significantly. Conclusions: Good control rates are reported for LINAC based SRS or SRT in VS, in which the lower rate of radiological growth control is attributed to the use of the more sensitive volume measurements. Transient swelling after radiosurgery is a common phenomenon and should not be mistaken for treatment failure. Previous treatment and SRS were significantly associated with transient swelling.

  4. Nitrogen rate strategies for reducing yield-scaled nitrous oxide emissions in maize

    Science.gov (United States)

    Zhao, Xu; Nafziger, Emerson D.; Pittelkow, Cameron M.

    2017-12-01

    Mitigating nitrogen (N) losses from agriculture without negatively impacting crop productivity is a pressing environmental and economic challenge. Reductions in N fertilizer rate are often highlighted as a solution, yet the degree to which crop yields and economic returns may be impacted at the field-level remains unclear, in part due to limited data availability. Farmers are risk averse and potential yield losses may limit the success of voluntary N loss mitigation protocols, thus understanding field-level yield tradeoffs is critical to inform policy development. Using a case study of soil N2O mitigation in the US Midwest, we conducted an ex-post assessment of two economic and two environmental N rate reduction strategies to identify promising practices for maintaining maize yields and economic returns while reducing N2O emissions per unit yield (i.e. yield-scaled emissions) compared to an assumed baseline N input level. Maize yield response data from 201 on-farm N rate experiments were combined with an empirical equation predicting N2O emissions as a function of N rate. Results indicate that the economic strategy aimed at maximizing returns to N (MRTN) led to moderate but consistent reductions in yield-scaled N2O emissions with small negative impacts on yield and slight increases in median returns. The economic optimum N rate strategy reduced yield-scaled N2O emissions in 75% of cases but increased them otherwise, challenging the assumption that this strategy will automatically reduce environmental impacts per unit production. Both environmental strategies, one designed to increase N recovery efficiency and one to balance N inputs with grain N removal, further reduced yield-scaled N2O emissions but were also associated with negative yield penalties and decreased returns. These results highlight the inherent tension between achieving agronomic and economic goals while reducing environmental impacts which is often overlooked in policy discussions. To enable the

  5. On-chip plasmonic cavity-enhanced spontaneous emission rate at the zero-phonon line

    DEFF Research Database (Denmark)

    Siampour, Hamidreza; Kumar, Shailesh; Bozhevolnyi, Sergey I.

    Highly confined surface plasmon polariton (SPP) modes can be utilized to enhance light-matter interaction at the single emitter level of quantum optical systems [1-4]. Dielectric-loaded SPP waveguides (DLSPPWs) confine SPPs laterally with relatively low propagation loss, enabling to benefit both ...... and an up to 42-fold spontaneous emission rate enhancement at the zero-phonon line (a ∼7-fold resonance enhancement in addition to a ∼6-fold broadband enhancement) is achieved, revealing the potential of our approach for on-chip realization of quantum-optical networks....... from a large Purcell factor and from a large radiative efficiency (low quenching rates) [1, 2]. In this work, we present a DLSPPW-based Bragg cavity resonator to direct emission from a single diamond nitrogen vacancy (NV) center into the zero-phonon line (Fig. 1). A quality factor of ∼70 for the cavity...

  6. Measurement of Gross Alpha and Beta Emission Rates from Ceramic Tiles

    International Nuclear Information System (INIS)

    Wudthicharoonpun, Piyasak; Chankow, Nares

    2007-08-01

    Full text: Ceramic tiles normally used to cover floors and walls contain naturally occurring radioactive elements i.e. potassium-40, uranium, thorium and their daughters from raw materials. Thus, radioactivity was dependent upon source of raw materials and the amount used. The objective of this research was to measure gross alpha and beta emission rates to be used as a database for safety assessment and for selection of rooms to measure radioactive radon-222 gas

  7. Increased Ratio of Electron Transport to Net Assimilation Rate Supports Elevated Isoprenoid Emission Rate in Eucalypts under Drought1[W][OPEN

    Science.gov (United States)

    Dani, Kaidala Ganesha Srikanta; Jamie, Ian McLeod; Prentice, Iain Colin; Atwell, Brian James

    2014-01-01

    Plants undergoing heat and low-CO2 stresses emit large amounts of volatile isoprenoids compared with those in stress-free conditions. One hypothesis posits that the balance between reducing power availability and its use in carbon assimilation determines constitutive isoprenoid emission rates in plants and potentially even their maximum emission capacity under brief periods of stress. To test this, we used abiotic stresses to manipulate the availability of reducing power. Specifically, we examined the effects of mild to severe drought on photosynthetic electron transport rate (ETR) and net carbon assimilation rate (NAR) and the relationship between estimated energy pools and constitutive volatile isoprenoid emission rates in two species of eucalypts: Eucalyptus occidentalis (drought tolerant) and Eucalyptus camaldulensis (drought sensitive). Isoprenoid emission rates were insensitive to mild drought, and the rates increased when the decline in NAR reached a certain species-specific threshold. ETR was sustained under drought and the ETR-NAR ratio increased, driving constitutive isoprenoid emission until severe drought caused carbon limitation of the methylerythritol phosphate pathway. The estimated residual reducing power unused for carbon assimilation, based on the energetic status model, significantly correlated with constitutive isoprenoid emission rates across gradients of drought (r2 > 0.8) and photorespiratory stress (r2 > 0.9). Carbon availability could critically limit emission rates under severe drought and photorespiratory stresses. Under most instances of moderate abiotic stress levels, increased isoprenoid emission rates compete with photorespiration for the residual reducing power not invested in carbon assimilation. A similar mechanism also explains the individual positive effects of low-CO2, heat, and drought stresses on isoprenoid emission. PMID:25139160

  8. 40 CFR Appendix III to Part 266 - Tier II Emission Rate Screening Limits for Free Chlorine and Hydrogen Chloride

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Tier II Emission Rate Screening Limits for Free Chlorine and Hydrogen Chloride III Appendix III to Part 266 Protection of Environment... to Part 266—Tier II Emission Rate Screening Limits for Free Chlorine and Hydrogen Chloride Terrain...

  9. Plutonium-aerosol emission rates and human pulmonary deposition calculations for Nuclear Site 201, Nevada Test Site

    International Nuclear Information System (INIS)

    Shinn, J.H.; Homan, D.N.

    1982-01-01

    This study determined the plutonium-aerosol fluxes from the soil to quantify (1) the extent of potential human exposure by deep-lung retention of alpha-emitting particles; (2) the source term should there be any significant, long-term, transport of plutonium aerosols; and (3) the resuspension factor and rate so that, for the first time at any nuclear site, one may calculate how long it will take for wind erosion to carry away a significant amount of the contaminated soil. High-volume air samplers and cascade impactors were used to characterize the plutonium aerosols. Meteorological flux-profile methods were used to calculate dust and plutonium aerosol emission rates. A floorless wind tunnel (10-m long) was used to examine resuspension under steady-state, high wind speed. The resuspension factor was two orders of magnitude lower than the other comparable sites at NTS and elsewhere, and the average resuspension rate of 5.3 x 10 -8 /d was also very low, so that the half-time for resuspension by wind erosion was about 36,000 y

  10. Methyl chavicol: characterization of its biogenic emission rate, abundance, and oxidation products in the atmosphere

    Directory of Open Access Journals (Sweden)

    N. C. Bouvier-Brown

    2009-03-01

    Full Text Available We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol was detected simultaneously by three in-situ instruments – a gas chromatograph with mass spectrometer detector (GC-MS, a proton transfer reaction mass spectrometer (PTR-MS, and a thermal desorption aerosol GC-MS (TAG – and found to be abundant within and above Blodgett Forest. Methyl chavicol atmospheric mixing ratios are strongly correlated with 2-methyl-3-buten-2-ol (MBO, a light- and temperature-dependent biogenic emission from the ponderosa pine trees at Blodgett Forest. Scaling from this correlation, methyl chavicol emissions account for 4–68% of the carbon mass emitted as MBO in the daytime, depending on the season. From this relationship, we estimate a daytime basal emission rate of 0.72–10.2 μgCg−1 h−1, depending on needle age and seasonality. We also present the first observations of its oxidation products (4-methoxybenzaldehyde and 4-methyoxy benzene acetaldehyde in the ambient atmosphere. Methyl chavicol is a major essential oil component of many plant species. This work suggests that methyl chavicol plays a significant role in the atmospheric chemistry of Blodgett Forest, and potentially other sites, and should be included explicitly in both biogenic volatile organic carbon emission and atmospheric chemistry models.

  11. Comparing facility-level methane emission rate estimates at natural gas gathering and boosting stations

    Directory of Open Access Journals (Sweden)

    Timothy L. Vaughn

    2017-11-01

    Full Text Available Coordinated dual-tracer, aircraft-based, and direct component-level measurements were made at midstream natural gas gathering and boosting stations in the Fayetteville shale (Arkansas, USA. On-site component-level measurements were combined with engineering estimates to generate comprehensive facility-level methane emission rate estimates (“study on-site estimates (SOE” comparable to tracer and aircraft measurements. Combustion slip (unburned fuel entrained in compressor engine exhaust, which was calculated based on 111 recent measurements of representative compressor engines, accounts for an estimated 75% of cumulative SOEs at gathering stations included in comparisons. Measured methane emissions from regenerator vents on glycol dehydrator units were substantially larger than predicted by modelling software; the contribution of dehydrator regenerator vents to the cumulative SOE would increase from 1% to 10% if based on direct measurements. Concurrent measurements at 14 normally-operating facilities show relative agreement between tracer and SOE, but indicate that tracer measurements estimate lower emissions (regression of tracer to SOE = 0.91 (95% CI = 0.83–0.99, R2 = 0.89. Tracer and SOE 95% confidence intervals overlap at 11/14 facilities. Contemporaneous measurements at six facilities suggest that aircraft measurements estimate higher emissions than SOE. Aircraft and study on-site estimate 95% confidence intervals overlap at 3/6 facilities. The average facility level emission rate (FLER estimated by tracer measurements in this study is 17–73% higher than a prior national study by Marchese et al.

  12. Effects of mass airflow rate through an open-circuit gas quantification system when measuring carbon emissions.

    Science.gov (United States)

    Gunter, Stacey A; Bradford, James A; Moffet, Corey A

    2017-01-01

    Methane (CH) and carbon dioxide (CO) represent 11 and 81%, respectively, of all anthropogenic greenhouse gas emissions. Agricultural CH emissions account for approximately 43% of all anthropogenic CH emissions. Most agricultural CH emissions are attributed to enteric fermentation within ruminant livestock; hence, the heightened interest in quantifying and mitigating this source. The automated, open-circuit gas quantification system (GQS; GreenFeed, C-Lock, Inc., Rapid City, SD) evaluated here can be placed in a pasture with grazing cattle and can measure their CH and CO emissions with spot sampling. However, improper management of the GQS can have an erroneous effect on emission estimates. One factor affecting the quality of emission estimates is the airflow rates through the GQS to ensure a complete capture of the breath cloud emitted by the animal. It is hypothesized that at lower airflow rates this cloud will be incompletely captured. To evaluate the effect of airflow rate through the GQS on emission estimates, a data set was evaluated with 758 CO and CH emission estimates with a range in airflows of 10.7 to 36.6 L/s. When airflow through the GQS was between 26.0 and 36.6 L/s, CO and CH emission estimates were not affected ( = 0.14 and 0.05, respectively). When airflow rates were less than 26.0 L/s, CO and CH emission estimates were lower and decreased as airflow rate decreased ( emissions are underestimated. Maintaining mass airflow through a GQS at rates greater than 26 L/s is important for producing high quality CO and CH emission estimates.

  13. Evaluation of regional cerebral blood flow and volume of rapidly exchangeable water in man by positron emission tomography

    International Nuclear Information System (INIS)

    Depresseux, J.C.; Cheslet, J.P.; Hodiaumont, J.

    1982-01-01

    The present investigation uses bolus inhalation of C 15 O 2 and sequential positron emission tomography of the brain in view to simultaneously evaluate regional cerebral blood flow and regional cerebral volume of rapidly exchangeable water in normal human subjects. Arguments allow to infer that the cerebral distribution volume of radiowater does vary with time during the initial period of invasion of tissue by the indicator. Implications of this variation on the validity of classical data procedures is discussed and an alternative original method is proposed [fr

  14. Global and regional annual brain volume loss rates in physiological aging.

    Science.gov (United States)

    Schippling, Sven; Ostwaldt, Ann-Christin; Suppa, Per; Spies, Lothar; Manogaran, Praveena; Gocke, Carola; Huppertz, Hans-Jürgen; Opfer, Roland

    2017-03-01

    The objective is to estimate average global and regional percentage brain volume loss per year (BVL/year) of the physiologically ageing brain. Two independent, cross-sectional single scanner cohorts of healthy subjects were included. The first cohort (n = 248) was acquired at the Medical Prevention Center (MPCH) in Hamburg, Germany. The second cohort (n = 316) was taken from the Open Access Series of Imaging Studies (OASIS). Brain parenchyma (BP), grey matter (GM), white matter (WM), corpus callosum (CC), and thalamus volumes were calculated. A non-parametric technique was applied to fit the resulting age-volume data. For each age, the BVL/year was derived from the age-volume curves. The resulting BVL/year curves were compared between the two cohorts. For the MPCH cohort, the BVL/year curve of the BP was an increasing function starting from 0.20% at the age of 35 years increasing to 0.52% at 70 years (corresponding values for GM ranged from 0.32 to 0.55%, WM from 0.02 to 0.47%, CC from 0.07 to 0.48%, and thalamus from 0.25 to 0.54%). Mean absolute difference between BVL/year trajectories across the age range of 35-70 years was 0.02% for BP, 0.04% for GM, 0.04% for WM, 0.11% for CC, and 0.02% for the thalamus. Physiological BVL/year rates were remarkably consistent between the two cohorts and independent from the scanner applied. Average BVL/year was clearly age and compartment dependent. These results need to be taken into account when defining cut-off values for pathological annual brain volume loss in disease models, such as multiple sclerosis.

  15. Factors influencing the recycling rate under the volume-based waste fee system in South Korea.

    Science.gov (United States)

    Park, Seejeen

    2018-04-01

    Since the early 2000s, the Republic of Korea (South Korea) has maintained its top-rank status for its municipal solid waste (MSW) recycling rate among OECD (Organization for Economic Cooperation and Development) member countries. The volume-based waste fee system (VWF) has been considered to be the major factor contributing to the high recycling performance, and extant research has verified the positive relationship between VWF adoption and the MSW recycling rate. Nevertheless, there exists a gap in the literature, as past research has focused more on testing the positive effects of VWF rather than on investigating the determinants of recycling rates after the adoption of VWF. The current study seeks to address this gap by investigating the various factors that affect recycling rates under the VWF system. More specifically, using data from 16 regions in South Korea over a period of 11 years, this study empirically tests the effects of VWF pricing, the citizen cost burden ratio for the VWF system, and pro-environmental behavior related to VWF on the recycling rate. The findings indicate that economic incentives such as cost savings on VWF plastic bag purchases and reduced burden from paying VWF expenses result in higher recycling rates. The findings also demonstrate that pro-environmental behavior in the VWF context positively affects the recycling rate. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Regional cerebral glucose metabolic rate in human sleep assessed by positron emission tomography

    International Nuclear Information System (INIS)

    Buchsbaum, M.S.; Wu, J.; Hazlett, E.; Sicotte, N.; Bunney, W.E. Jr.; Gillin, J.C.

    1989-01-01

    The cerebral metabolic rate of glucose was measured during nighttime sleep in 36 normal volunteers using positron emission tomography and fluorine-18-labeled 2-deoxyglucose (FDG). In comparison to waking controls, subjects given FDG during non-rapid eye movement (NREM) sleep showed about a 23% reduction in metabolic rate across the entire brain. This decrease was greater for the frontal than temporal or occipital lobes, and greater for basal ganglia and thalamus than cortex. Subjects in rapid eye movement (REM) sleep tended to have higher cortical metabolic rates than walking subjects. The cingulate gyrus was the only cortical structure to show a significant increase in glucose metabolic rate in REM sleep in comparison to waking. The basal ganglia were relatively more active on the right in REM sleep and symmetrical in NREM sleep

  17. Sustainable Use of Pesticide Applications in Citrus: A Support Tool for Volume Rate Adjustment

    Directory of Open Access Journals (Sweden)

    Cruz Garcerá

    2017-06-01

    Full Text Available Rational application of pesticides by properly adjusting the amount of product to the actual needs and specific conditions for application is a key factor for sustainable plant protection. However, current plant protection product (PPP labels registered for citrus in EU are usually expressed as concentration (%; rate/hl and/or as the maximum dose of product per unit of ground surface, without taking into account those conditions. In this work, the fundamentals of a support tool, called CitrusVol, developed to recommend mix volume rates in PPP applications in citrus orchards using airblast sprayers, are presented. This tool takes into consideration crop characteristics (geometry, leaf area density, pests, and product and application efficiency, and it is based on scientific data obtained previously regarding the minimum deposit required to achieve maximum efficacy, efficiency of airblast sprayers in citrus orchards, and characterization of the crop. The use of this tool in several commercial orchards allowed a reduction of the volume rate and the PPPs used in comparison with the commonly used by farmers of between 11% and 74%, with an average of 31%, without affecting the efficacy. CitrusVol is freely available on a website and in an app for smartphones.

  18. Intraoperative stroke volume optimization using stroke volume, arterial pressure, and heart rate: closed-loop (learning intravenous resuscitator) versus anesthesiologists.

    Science.gov (United States)

    Rinehart, Joseph; Chung, Elena; Canales, Cecilia; Cannesson, Maxime

    2012-10-01

    The authors compared the performance of a group of anesthesia providers to closed-loop (Learning Intravenous Resuscitator [LIR]) management in a simulated hemorrhage scenario using cardiac output monitoring. A prospective cohort study. In silico simulation. University hospital anesthesiologists and the LIR closed-loop fluid administration system. Using a patient simulator, a 90-minute simulated hemorrhage protocol was run, which included a 1,200-mL blood loss over 30 minutes. Twenty practicing anesthesiology providers were asked to manage this scenario by providing fluids and vasopressor medication at their discretion. The simulation program was also run 20 times with the LIR closed-loop algorithm managing fluids and an additional 20 times with no intervention. Simulated patient weight, height, heart rate, mean arterial pressure, and cardiac output (CO) were similar at baseline. The mean stroke volume, the mean arterial pressure, CO, and the final CO were higher in the closed-loop group than in the practitioners group, and the coefficient of variance was lower. The closed-loop group received slightly more fluid (2.1 v 1.9 L, p closed-loop maintained more stable hemodynamics than the practitioners primarily because the fluid was given earlier in the protocol and CO optimized before the hemorrhage began, whereas practitioners tended to resuscitate well but only after significant hemodynamic change indicated the need. Overall, these data support the potential usefulness of this closed-loop algorithm in clinical settings in which dynamic predictors are not available or applicable. Published by Elsevier Inc.

  19. Indoor acrolein emission and decay rates resulting from domestic cooking events

    Science.gov (United States)

    Seaman, Vincent Y.; Bennett, Deborah H.; Cahill, Thomas M.

    2009-12-01

    Acrolein (2-propenal) is a common constituent of both indoor and outdoor air, can exacerbate asthma in children, and may contribute to other chronic lung diseases. Recent studies have found high indoor levels of acrolein and other carbonyls compared to outdoor ambient concentrations. Heated cooking oils produce considerable amounts of acrolein, thus cooking is likely an important source of indoor acrolein. A series of cooking experiments were conducted to determine the emission rates of acrolein and other volatile carbonyls for different types of cooking oils (canola, soybean, corn and olive oils) and deep-frying different food items. Similar concentrations and emission rates of carbonyls were found when different vegetable oils were used to deep-fry the same food product. The food item being deep-fried was generally not a significant source of carbonyls compared to the cooking oil. The oil cooking events resulted in high concentrations of acrolein that were in the range of 26.4-64.5 μg m -3. These concentrations exceed all the chronic regulatory exposure limits and many of the acute exposure limits. The air exchange rate and the decay rate of the carbonyls were monitored to estimate the half-life of the carbonyls. The half-life for acrolein was 14.4 ± 2.6 h, which indicates that indoor acrolein concentrations can persist for considerable time after cooking in poorly-ventilated homes.

  20. Real-world volatile organic compound emission rates from seated adults and children for use in indoor air studies.

    Science.gov (United States)

    Stönner, C; Edtbauer, A; Williams, J

    2018-01-01

    Human beings emit many volatile organic compounds (VOCs) of both endogenous (internally produced) and exogenous (external source) origin. Here we present real-world emission rates of volatile organic compounds from cinema audiences (50-230 people) as a function of time in multiple screenings of three films. The cinema location and film selection allowed high-frequency measurement of human-emitted VOCs within a room flushed at a known rate so that emissions rates could be calculated for both adults and children. Gas-phase emission rates are analyzed as a function of time of day, variability during the film, and age of viewer. The average emission rates of CO 2 , acetone, and isoprene were lower (by a factor of ~1.2-1.4) for children under twelve compared to adults while for acetaldehyde emission rates were equivalent. Molecules influenced by exogenous sources such as decamethylcyclopentasiloxanes and methanol tended to decrease over the course of day and then rise for late evening screenings. These results represent average emission rates of people under real-world conditions and can be used in indoor air quality assessments and building design. Averaging over a large number of people generates emission rates that are less susceptible to individual behaviors. © 2017 The Authors. Indoor Air published by John Wiley & Sons Ltd.

  1. Effects of soil water content and elevated CO2 concentration on the monoterpene emission rate of Cryptomeria japonica.

    Science.gov (United States)

    Mochizuki, Tomoki; Amagai, Takashi; Tani, Akira

    2018-04-11

    Monoterpenes emitted from plants contribute to the formation of secondary pollution and affect the climate system. Monoterpene emission rates may be affected by environmental changes such as increasing CO 2 concentration caused by fossil fuel burning and drought stress induced by climate change. We measured monoterpene emissions from Cryptomeria japonica clone saplings grown under different CO 2 concentrations (control: ambient CO 2 level, elevated CO 2 : 1000μmolmol -1 ). The saplings were planted in the ground and we did not artificially control the SWC. The relationship between the monoterpene emissions and naturally varying SWC was investigated. The dominant monoterpene was α-pinene, followed by sabinene. The monoterpene emission rates were exponentially correlated with temperature for all measurements and normalized (35°C) for each measurement day. The daily normalized monoterpene emission rates (E s0.10 ) were positively and linearly correlated with SWC under both control and elevated CO 2 conditions (control: r 2 =0.55, elevated CO 2 : r 2 =0.89). The slope of the regression line of E s0.10 against SWC was significantly higher under elevated CO 2 than under control conditions (ANCOVA: P<0.01), indicating that the effect of CO 2 concentration on monoterpene emission rates differed by soil water status. The monoterpene emission rates estimated by considering temperature and SWC (Improved G93 algorithm) better agreed with the measured monoterpene emission rates, when compared with the emission rates estimated by considering temperature alone (G93 algorithm). Our results demonstrated that the combined effects of SWC and CO 2 concentration are important for controlling the monoterpene emissions from C. japonica clone saplings. If these relationships can be applied to the other coniferous tree species, our results may be useful to improve accuracy of monoterpene emission estimates from the coniferous forests as affected by climate change in the present and

  2. Evaluation of left ventricular function and volume with multidetector-row computed tomography. Comparison with electrocardiogram-gated single photon emission computed tomography

    International Nuclear Information System (INIS)

    Suzuki, Takeya; Yamashina, Shohei; Nanjou, Shuji; Yamazaki, Junichi

    2007-01-01

    This study compared left ventricular systolic function and volume determined by multidetector-row computed tomography (MDCT) and electrocardiogram-gated single photon emission computed tomography (G-SPECT) Thirty-seven patients with coronary artery disease and non-cardiovascular disease underwent MDCT. In this study, left ventricular ejection fraction (EF), left ventricular end-diastolic volume (EDV) and left ventricular end-systolic volume (ESV) were calculated using only two-phase imaging with MDCT. Left ventricular function and volume were compared using measurements from G-SPECT. We conducted MDCT and G-SPECT virtually simultaneously. Both the EF and ESV evaluated by MDCT closely correlated with G-SPECT (r=0.763, P 65 bpm) during MDCT significantly influenced the difference in EF calculated from MDCT and G-SPECT (P<0.05). Left ventricular function can be measured with MDCT as well as G-SPECT. However, a heart rate over 65 bpm during MDCT negatively affects the EF correlation between MDCT and G-SPECT. (author)

  3. Analysis of Emission Effects Related to Drivers’ Compliance Rates for Cooperative Vehicle-Infrastructure System at Signalized Intersections

    Directory of Open Access Journals (Sweden)

    Ruohua Liao

    2018-01-01

    Full Text Available Unknown remaining time of signal phase at a signalized intersection generally results in extra accelerations and decelerations that increase variations of operating conditions and thus emissions. A cooperative vehicle-infrastructure system can reduce unnecessary speed changes by establishing communications between vehicles and the signal infrastructure. However, the environmental benefits largely depend on drivers’ compliance behaviors. To quantify the effects of drivers’ compliance rates on emissions, this study applied VISSIM 5.20 (Planung Transport Verkehr AG, Karlsruhe, Germany to develop a simulation model for a signalized intersection, in which light duty vehicles were equipped with a cooperative vehicle-infrastructure system. A vehicle-specific power (VSP-based model was used to estimate emissions. Based on simulation data, the effects of different compliance rates on VSP distributions, emission factors, and total emissions were analyzed. The results show the higher compliance rate decreases the proportion of VSP bin = 0, which means that the frequencies of braking and idling were lower and light duty vehicles ran more smoothly at the intersection if more light duty vehicles complied with the cooperative vehicle-infrastructure system, and emission factors for light duty vehicles decreased significantly as the compliance rate increased. The case study shows higher total emission reductions were observed with higher compliance rate for all of CO2, NOx, HC, and CO emissions. CO2 was reduced most significantly, decreased by 16% and 22% with compliance rates of 0.3 and 0.7, respectively.

  4. Analysis of Emission Effects Related to Drivers' Compliance Rates for Cooperative Vehicle-Infrastructure System at Signalized Intersections.

    Science.gov (United States)

    Liao, Ruohua; Chen, Xumei; Yu, Lei; Sun, Xiaofei

    2018-01-12

    Unknown remaining time of signal phase at a signalized intersection generally results in extra accelerations and decelerations that increase variations of operating conditions and thus emissions. A cooperative vehicle-infrastructure system can reduce unnecessary speed changes by establishing communications between vehicles and the signal infrastructure. However, the environmental benefits largely depend on drivers' compliance behaviors. To quantify the effects of drivers' compliance rates on emissions, this study applied VISSIM 5.20 (Planung Transport Verkehr AG, Karlsruhe, Germany) to develop a simulation model for a signalized intersection, in which light duty vehicles were equipped with a cooperative vehicle-infrastructure system. A vehicle-specific power (VSP)-based model was used to estimate emissions. Based on simulation data, the effects of different compliance rates on VSP distributions, emission factors, and total emissions were analyzed. The results show the higher compliance rate decreases the proportion of VSP bin = 0, which means that the frequencies of braking and idling were lower and light duty vehicles ran more smoothly at the intersection if more light duty vehicles complied with the cooperative vehicle-infrastructure system, and emission factors for light duty vehicles decreased significantly as the compliance rate increased. The case study shows higher total emission reductions were observed with higher compliance rate for all of CO₂, NO x , HC, and CO emissions. CO₂ was reduced most significantly, decreased by 16% and 22% with compliance rates of 0.3 and 0.7, respectively.

  5. Analysis of Emission Effects Related to Drivers’ Compliance Rates for Cooperative Vehicle-Infrastructure System at Signalized Intersections

    Science.gov (United States)

    Liao, Ruohua; Yu, Lei; Sun, Xiaofei

    2018-01-01

    Unknown remaining time of signal phase at a signalized intersection generally results in extra accelerations and decelerations that increase variations of operating conditions and thus emissions. A cooperative vehicle-infrastructure system can reduce unnecessary speed changes by establishing communications between vehicles and the signal infrastructure. However, the environmental benefits largely depend on drivers’ compliance behaviors. To quantify the effects of drivers’ compliance rates on emissions, this study applied VISSIM 5.20 (Planung Transport Verkehr AG, Karlsruhe, Germany) to develop a simulation model for a signalized intersection, in which light duty vehicles were equipped with a cooperative vehicle-infrastructure system. A vehicle-specific power (VSP)-based model was used to estimate emissions. Based on simulation data, the effects of different compliance rates on VSP distributions, emission factors, and total emissions were analyzed. The results show the higher compliance rate decreases the proportion of VSP bin = 0, which means that the frequencies of braking and idling were lower and light duty vehicles ran more smoothly at the intersection if more light duty vehicles complied with the cooperative vehicle-infrastructure system, and emission factors for light duty vehicles decreased significantly as the compliance rate increased. The case study shows higher total emission reductions were observed with higher compliance rate for all of CO2, NOx, HC, and CO emissions. CO2 was reduced most significantly, decreased by 16% and 22% with compliance rates of 0.3 and 0.7, respectively. PMID:29329214

  6. Dose volume assessment of high dose rate 192IR endobronchial implants

    International Nuclear Information System (INIS)

    Cheng, B. Saw; Korb, Leroy J.; Pawlicki, Todd; Wu, Andrew

    1996-01-01

    Purpose: To study the dose distributions of high dose rate (HDR) endobronchial implants using the dose nonuniformity ratio (DNR) and three volumetric irradiation indices. Methods and Materials: Multiple implants were configured by allowing a single HDR 192 Ir source to step through a length of 6 cm along an endobronchial catheter. Dwell times were computed to deliver a dose of 5 Gy to points 1 cm away from the catheter axis. Five sets of source configurations, each with different dwell position spacings from 0.5 to 3.0 cm, were evaluated. Three-dimensional (3D) dose distributions were then generated for each source configuration. Differential and cumulative dose-volume curves were generated to quantify the degree of target volume coverage, dose nonuniformity within the target volume, and irradiation of tissues outside the target volume. Evaluation of the implants were made using the DNR and three volumetric irradiation indices. Results: The observed isodose distributions were not able to satisfy all the dose constraints. The ability to optimally satisfy the dose constraints depended on the choice of dwell position spacing and the specification of the dose constraint points. The DNR and irradiation indices suggest that small dwell position spacing does not result in a more homogeneous dose distribution for the implant. This study supports the existence of a relationship between the dwell position spacing and the distance from the catheter axis to the reference dose or dose constraint points. Better dose homogeneity for an implant can be obtained if the spacing of the dwell positions are about twice the distance from the catheter axis to the reference dose or dose constraint points

  7. Vehicle-based road dust emission measurement (III):. effect of speed, traffic volume, location, and season on PM 10 road dust emissions in the Treasure Valley, ID

    Science.gov (United States)

    Etyemezian, V.; Kuhns, H.; Gillies, J.; Chow, J.; Hendrickson, K.; McGown, M.; Pitchford, M.

    The testing re-entrained aerosol kinetic emissions from roads (TRAKER) road dust measurement system was used to survey more than 400 km of paved roads in southwestern Idaho during 3-week sampling campaigns in winter and summer, 2001. Each data point, consisting of a 1-s measurement of particle light scattering sampled behind the front tire, was associated with a link (section of road) in the traffic demand model network for the Treasure Valley, ID. Each link was in turn associated with a number of characteristics including posted speed limit, vehicle kilometers traveled (vkt), road class (local/residential, collector, arterial, and interstate), county, and land use (urban vs. rural). Overall, the TRAKER-based emission factors based on location, setting, season, and speed spanned a narrow range from 3.6 to 8.0 g/vkt. Emission factors were higher in winter compared to summer, higher in urban areas compared to rural, and lower for roads with fast travel speeds compared to slower roads. The inherent covariance between traffic volume and traffic speed obscured the assessment of the effect of traffic volume on emission potentials. Distance-based emission factors expressed in grams per kilometer traveled (g/vkt) for roads with low travel speeds (˜11 m/s residential roads) compared to those with high travel speeds (˜25 m/s interstates) were higher (5.2 vs. 3.0 g/vkt in summer and 5.9 vs. 4.9 g/vkt in winter). However, emission potentials which characterize the amount of suspendable material on a road were substantially higher on roads with low travel speeds (0.71 vs. 0.13 g/vkt/(m/s) in summer and 0.78 vs. 0.21 g/vkt/(m/s) in winter). This suggested that while high speed roads are much cleaner (factor of 5.4 in summer), on a vehicle kilometer traveled basis, emissions from high and low speed roads are of the same order. Emission inventories based on the TRAKER method, silt loadings obtained during the field study, and US EPA's AP-42 default values of silt loading were

  8. Something from nothing: Estimating consumption rates using propensity scores, with application to emissions reduction policies.

    Directory of Open Access Journals (Sweden)

    Nicholas Bardsley

    Full Text Available Consumption surveys often record zero purchases of a good because of a short observation window. Measures of distribution are then precluded and only mean consumption rates can be inferred. We show that Propensity Score Matching can be applied to recover the distribution of consumption rates. We demonstrate the method using the UK National Travel Survey, in which c.40% of motorist households purchase no fuel. Estimated consumption rates are plausible judging by households' annual mileages, and highly skewed. We apply the same approach to estimate CO2 emissions and outcomes of a carbon cap or tax. Reliance on means apparently distorts analysis of such policies because of skewness of the underlying distributions. The regressiveness of a simple tax or cap is overstated, and redistributive features of a revenue-neutral policy are understated.

  9. Positron emission tomography suggests that the rate of progression of idiopathic parkinsonism is slow

    International Nuclear Information System (INIS)

    Bhatt, M.H.; Snow, B.J.; Martin, W.R.; Pate, B.D.; Ruth, T.J.; Calne, D.B.

    1991-01-01

    The authors performed sequential positron emission tomography scans with 6-[18F]fluoro-L-dopa in 9 patients with idiopathic parkinsonism and 7 age-matched normal control subjects to compare changes in the nigrostriatal dopaminergic pathway over time. The mean interval between the scans was 3.3 years for the group with idiopathic parkinsonism and 3.9 years for the control subjects. The scans were analyzed by calculating the ratio of striatal to background radioactivity. Both groups showed statistically significant reductions of striatal uptake over the interval. The rate of decrease was almost identical in each group (p = 0.6). They infer that the usual rate of loss of integrity of the dopaminergic nigrostriatal pathway in patients with idiopathic parkinsonism is slow and the rate of change between the two groups was comparable

  10. Plasma volume, intravascular albumin and its transcapillary escape rate in patients with extensive skin disease

    DEFF Research Database (Denmark)

    Parving, H H; Worm, A M; Rossing, N

    1976-01-01

    Plasma volume and plasma concentration and transcapillary escape rate of albumin (TER alb), i.e. the fraction of intravascular mass of albumin that passes to the extravascular space per unit time, were determined using 125I-labelled human albumin in eight patients with extensive skin disease....... Plasma volume and plasma albumin concentration were reduced (P less than 0-05). Thus the intravascular albumin mass was moderately decreased to an average of 0-55 +/- 0-06 (s.d.) g/cm height compared with a normal mean value of 0-77 +/- 0-07 (s.d.) g/cm. This 29% decrease is statistically significant (P...... less than 0-001). The transcapillary escape rate of albumin (TER alb) was significantly elevated, mean 8-6 +/- 1-1 (s.d.) % X h-1, as compared to normal subjects, mean 5-6 +/- 1-1 (s.d.) % X h-1, (+54%, P less than 0-001). The same patients were studied again after a 1-week treatment with prednisone...

  11. The forgotten role of central volume in low frequency oscillations of heart rate variability.

    Directory of Open Access Journals (Sweden)

    Manuela Ferrario

    Full Text Available The hypothesis that central volume plays a key role in the source of low frequency (LF oscillations of heart rate variability (HRV was tested in a population of end stage renal disease patients undergoing conventional hemodialysis (HD treatment, and thus subject to large fluid shifts and sympathetic activation. Fluid overload (FO in 58 chronic HD patients was assessed by whole body bioimpedance measurements before the midweek HD session. Heart Rate Variability (HRV was measured using 24-hour Holter electrocardiogram recordings starting before the same HD treatment. Time domain and frequency domain analyses were performed on HRV signals. Patients were retrospectively classified in three groups according to tertiles of FO normalized to the extracellular water (FO/ECW%. These groups were also compared after stratification by diabetes mellitus. Patients with the low to medium hydration status before the treatment (i.e. 1st and 2nd FO/ECW% tertiles showed a significant increase in LF power during last 30 min of HD compared to dialysis begin, while no significant change in LF power was seen in the third group (i.e. those with high pre-treatment hydration values. In conclusion, several mechanisms can generate LF oscillations in the cardiovascular system, including baroreflex feedback loops and central oscillators. However, the current results emphasize the role played by the central volume in determining the power of LF oscillations.

  12. The forgotten role of central volume in low frequency oscillations of heart rate variability.

    Science.gov (United States)

    Ferrario, Manuela; Moissl, Ulrich; Garzotto, Francesco; Cruz, Dinna N; Tetta, Ciro; Signorini, Maria G; Ronco, Claudio; Grassmann, Aileen; Cerutti, Sergio; Guzzetti, Stefano

    2015-01-01

    The hypothesis that central volume plays a key role in the source of low frequency (LF) oscillations of heart rate variability (HRV) was tested in a population of end stage renal disease patients undergoing conventional hemodialysis (HD) treatment, and thus subject to large fluid shifts and sympathetic activation. Fluid overload (FO) in 58 chronic HD patients was assessed by whole body bioimpedance measurements before the midweek HD session. Heart Rate Variability (HRV) was measured using 24-hour Holter electrocardiogram recordings starting before the same HD treatment. Time domain and frequency domain analyses were performed on HRV signals. Patients were retrospectively classified in three groups according to tertiles of FO normalized to the extracellular water (FO/ECW%). These groups were also compared after stratification by diabetes mellitus. Patients with the low to medium hydration status before the treatment (i.e. 1st and 2nd FO/ECW% tertiles) showed a significant increase in LF power during last 30 min of HD compared to dialysis begin, while no significant change in LF power was seen in the third group (i.e. those with high pre-treatment hydration values). In conclusion, several mechanisms can generate LF oscillations in the cardiovascular system, including baroreflex feedback loops and central oscillators. However, the current results emphasize the role played by the central volume in determining the power of LF oscillations.

  13. GLOBAL STAR FORMATION RATES AND DUST EMISSION OVER THE GALAXY INTERACTION SEQUENCE

    Energy Technology Data Exchange (ETDEWEB)

    Lanz, Lauranne; Zezas, Andreas; Smith, Howard A.; Ashby, Matthew L. N.; Fazio, Giovanni G.; Hernquist, Lars [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Brassington, Nicola [School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield, AL10 9AB (United Kingdom); Da Cunha, Elisabete [Max Planck Institute for Astronomy (MPIA), Koenigstuhl 17, D-69117, Heidelberg (Germany); Hayward, Christopher C. [Heidelberger Institut fuer Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118, Heidelberg (Germany); Jonsson, Patrik, E-mail: llanz@head.cfa.harvard.edu [Space Exploration Technologies, 1 Rocket Road, Hawthorne, CA 90250 (United States)

    2013-05-01

    We measured and modeled spectral energy distributions (SEDs) in 28 bands from the ultraviolet to the far-infrared (FIR) for 31 interacting galaxies in 14 systems. The sample is drawn from the Spitzer Interacting Galaxy Survey, which probes a range of galaxy interaction parameters at multiple wavelengths with an emphasis on the infrared bands. The subset presented in this paper consists of all galaxies for which FIR Herschel SPIRE observations are publicly available. Our SEDs combine the Herschel photometry with multi-wavelength data from Spitzer, GALEX, Swift UVOT, and 2MASS. While the shapes of the SEDs are broadly similar across our sample, strongly interacting galaxies typically have more mid-infrared emission relative to their near-infrared and FIR emission than weakly or moderately interacting galaxies. We modeled the full SEDs to derive host galaxy star formation rates (SFRs), specific star formation rates (sSFRs), stellar masses, dust temperatures, dust luminosities, and dust masses. We find increases in the dust luminosity and mass, SFR, and cold (15-25 K) dust temperature as the interaction progresses from moderately to strongly interacting and between non-interacting and strongly interacting galaxies. We also find increases in the SFR between weakly and strongly interacting galaxies. In contrast, the sSFR remains unchanged across all the interaction stages. The ultraviolet photometry is crucial for constraining the age of the stellar population and the SFR, while dust mass is primarily determined by SPIRE photometry. The SFR derived from the SED modeling agrees well with rates estimated by proportionality relations that depend on infrared emission.

  14. Mass transfer inside a flux hood for the sampling of gaseous emissions from liquid surfaces - Experimental assessment and emission rate rescaling

    Science.gov (United States)

    Prata, Ademir A.; Lucernoni, Federico; Santos, Jane M.; Capelli, Laura; Sironi, Selena; Le-Minh, Nhat; Stuetz, Richard M.

    2018-04-01

    This study assesses the mass transfer of compounds inside the US EPA flux hood, one of the enclosure devices most commonly employed for the direct measurement of atmospheric emissions from liquid surfaces in wastewater treatment plants (WWTPs). Experiments comprised the evaporation of water and the volatilisation of a range of volatile organic compounds (VOCs). Special attention was given to the evaluation of the mass transfer coefficients in the microenvironment created by the flux hood and the effects of concentration build up in the hood's headspace. The VOCs emission rates and the water evaporation rates generally increased with the sweep air flow rate, as did the mass transfer coefficients for all compounds. The emission of compounds whose volatilisation is significantly influenced by the gas phase was greatly affected by concentration build up, whereas this effect was not significant for liquid phase-controlled compounds. The gas-film mass transfer coefficient (kG) estimated inside the US EPA flux hood was of the same order as the respective kG reported in the literature for wind tunnel-type devices, but the emission rates measured by the flux hood can be expected to be lower, due to the concentration build-up. Compared against an emission model for the passive surfaces in WWTPs, the mass transfer of acetic acid (representing a gas phase-dominated compound) inside the US EPA flux hood was equivalent to conditions of wind speeds at 10 m height (U10) of 0.27, 0.51 and 0.99 m s-1, respectively, for sweep air flow rates of 2, 5 and 10 L min-1. On the other hand, for higher wind speeds, the emission rates of gas phase-controlled compounds obtained with the flux hood can be considerably underestimated: for instance, at U10 = 5 m s-1, the emission rates of acetic acid inside the flux hood would be approximately 23, 12 and 6 times lower than the emission rates in the field, for sweep air flow rates of 2, 5 and 10 L min-1, respectively. A procedure is presented in

  15. Study on the Measurement of Valve Leak Rate Using Acoustic Emission Technology

    International Nuclear Information System (INIS)

    Lee, Sang-Guk; Park, Jong-Hyuck; Yoo, Keun-Bae; Lee, Sun-Ki; Hong, Sung-Yull

    2006-01-01

    This study is to estimate the feasibility of acoustic emission(AE) method for the internal leak from the valves. In this study, 4 inch ball water valve leak tests using three different leak path and various leak rates were performed in order to analyze AE properties when leaks arise in valve seat. As a result of leak test for specimens simulated valve seat, we conformed that leak sound amplitude increased in proportion to the increase of leak rate, and leak rates were plotted versus peak acoustic amplitudes recorded within those two narrow frequency bands on each spectrum plot. The resulting plots of leak rate versus peak AE amplitude were the primary basis for determining the feasibility of quantifying leak acoustically. The large amount of data attained also allowed a favorable investigation of the effects of different leak paths, leak rates, pressure differentials and AE sensors on the AE amplitude spectrum. From the experimental results, it was suggested that the AE method for monitoring of leak was feasible. This paper describes quantitative measurements of fluid valve leak rates by the analysis of AE. Experimental apparatus were fabricated to accept a variety of leaking water valves in order to determine what characteristics of AE signal change with leak rate. The data for each valve were generated by varying the leak rate and recording the time averaged amplitude of AE versus frequency. Leak rates were varied by modifying the valve seating surfaces in ways designed to simulate actual defects observed in service. Most of the data analysis involved plotting the leak rate versus signal amplitude at a specific frequency to determine how well the two variables correlate in terms of accuracy, resolution, and repeatability

  16. Establishing pathological cut-offs for lateral ventricular volume expansion rates

    Directory of Open Access Journals (Sweden)

    Michael G. Dwyer

    Full Text Available Background: A percent brain volume change (PBVC cut-off of −0.4% per year has been proposed to distinguish between pathological and physiological changes in multiple sclerosis (MS. Unfortunately, standardized PBVC measurement is not always feasible on scans acquired outside research studies or academic centers. Percent lateral ventricular volume change (PLVVC is a strong surrogate measure of PBVC, and may be more feasible for atrophy assessment on real-world scans. However, the PLVVC rate corresponding to the established PBVC cut-off of −0.4% is unknown. Objective: To establish a pathological PLVVC expansion rate cut-off analogous to −0.4% PBVC. Methods: We used three complementary approaches. First, the original follow-up-length-weighted receiver operating characteristic (ROC analysis method establishing whole brain atrophy rates was adapted to a longitudinal ventricular atrophy dataset of 177 relapsing-remitting MS (RRMS patients and 48 healthy controls. Second, in the same dataset, SIENA PBVCs were used with non-linear regression to directly predict the PLVVC value corresponding to −0.4% PBVC. Third, in an unstandardized, real world dataset of 590 RRMS patients from 33 centers, the cut-off maximizing correspondence to PBVC was found. Finally, correspondences to clinical outcomes were evaluated in both datasets. Results: ROC analysis suggested a cut-off of 3.09% (AUC = 0.83, p < 0.001. Non-linear regression R2 was 0.71 (p < 0.001 and a − 0.4% PBVC corresponded to a PLVVC of 3.51%. A peak in accuracy in the real-world dataset was found at a 3.51% PLVVC cut-off. Accuracy of a 3.5% cut-off in predicting clinical progression was 0.62 (compared to 0.68 for PBVC. Conclusions: Ventricular expansion of between 3.09% and 3.51% on T2-FLAIR corresponds to the pathological whole brain atrophy rate of 0.4% for RRMS. A conservative cut-off of 3.5% performs comparably to PBVC for clinical outcomes. Keywords: Brain atrophy

  17. Modelling of N21P emission rates in aurora using various cross sections for excitation

    Directory of Open Access Journals (Sweden)

    O. Jokiaho

    2009-06-01

    Full Text Available Measurements of N21P auroral emissions from the (4,1 and (5,2 bands have been made at high temporal and spatial resolution in the region of the magnetic zenith. The instrument used was the auroral imager ASK, situated at Ramfjordmoen, Norway (69.6 N, 19.2 E on 22 October 2006. Measurements from the European Incoherent Scatter Radar (EISCAT have been combined with the optical measurements, and incorporated into an ionospheric model to obtain height profiles of electron density and emission rates of the N21P bands. The radar data provide essential verification that the energy flux used in the model is correct. One of the most important inputs to the model is the cross section for excitation to the B3Πg electronic state, as well as the cross sections to higher states from which cascading into the B state occurs. The balance equations for production and loss of the populations of all levels in each state are solved in order to find the cascade contributions. Several sets of cross sections have been considered, and selected cross sections have been used to construct "emission" cross sections for the observed bands. The resulting brightnesses are compared with those measured by ASK. The importance of specific contributions from cascading is found, with more than 50% of the total brightness resulting from cascading. The cross sections used are found to produce a range of brightnesses well within the uncertainty of both the modelled and measured values.

  18. Natural gas fugitive emissions rates constrained by global atmospheric methane and ethane.

    Science.gov (United States)

    Schwietzke, Stefan; Griffin, W Michael; Matthews, H Scott; Bruhwiler, Lori M P

    2014-07-15

    The amount of methane emissions released by the natural gas (NG) industry is a critical and uncertain value for various industry and policy decisions, such as for determining the climate implications of using NG over coal. Previous studies have estimated fugitive emissions rates (FER)--the fraction of produced NG (mainly methane and ethane) escaped to the atmosphere--between 1 and 9%. Most of these studies rely on few and outdated measurements, and some may represent only temporal/regional NG industry snapshots. This study estimates NG industry representative FER using global atmospheric methane and ethane measurements over three decades, and literature ranges of (i) tracer gas atmospheric lifetimes, (ii) non-NG source estimates, and (iii) fossil fuel fugitive gas hydrocarbon compositions. The modeling suggests an upper bound global average FER of 5% during 2006-2011, and a most likely FER of 2-4% since 2000, trending downward. These results do not account for highly uncertain natural hydrocarbon seepage, which could lower the FER. Further emissions reductions by the NG industry may be needed to ensure climate benefits over coal during the next few decades.

  19. Greenhouse gas emission controls : differentiated vs. flat rate targets : impacts and concerts

    International Nuclear Information System (INIS)

    Heydanek, D.

    1997-01-01

    Continuing the discussion on differentiation in greenhouse gas emission targets and timetables for all nations, the different implications of differentiation vs. flat rate controls were examined. A scenario of how different targets for different countries based on national circumstances might be implemented, was presented. Implications of differentiation for the Dow Chemical Company were also reviewed. For more than 20 years, Dow has practiced leading edge energy efficiency in environmental management systems and has committed to a series of environmental, health and safety goals. The company believes that at the international level, fully differentiated targets and timetables need to be negotiated, party by party, by the 150 nations who agreed to stabilize greenhouse gas emissions at 1990 levels by year 2000. It was suggested that a strong disincentive exists to delivering energy efficiency beyond compliance. It was predicted that despite efficiency, the energy intensive assets in place today in Annex I countries will be disadvantaged and prematurely retired as the costs of greenhouse gas emission controls grow and exert pressure to move productive capacity offshore

  20. Examination of the optimal operation of building scale combined heat and power systems under disparate climate and GHG emissions rates

    International Nuclear Information System (INIS)

    Howard, B.; Modi, V.

    2017-01-01

    Highlights: • CHP attributable reductions, not viable by electric generation alone, are defined. • Simplified operating strategy heuristics are optimal under specific circumstances. • Phosphoric acid fuel cells yield the largest reductions except in the extremes. • Changes in baseline emissions affect the optimal system capacity and operating hours. - Abstract: This work aims to elucidate notions concerning the ideal operation and greenhouse gas (GHG) emissions benefits of combined heat and power (CHP) systems by investigating how various metrics change as a function of the GHG emissions from the underlying electricity source, building use type and climate. Additionally, a new term entitled “CHP Attributable” reductions is introduced to quantify the benefits from the simultaneous use of thermal and electric energy, removing benefits achieved solely from fuel switching and generating electricity more efficiently. The GHG emission benefits from implementing internal combustion engine, microturbines, and phosphoric acid (PA) fuel cell based CHP systems were evaluated through an optimization approach considering energy demands of prototypical hospital, office, and residential buildings in varied climates. To explore the effect of electric GHG emissions rates, the ideal operation of the CHP systems was evaluated under three scenarios: “High” GHG emissions rates, “Low” GHG emissions rates, and “Current” GHG emissions rate for a specific location. The analysis finds that PA fuel cells achieve the highest GHG emission reductions in most cases considered, though there are exceptions. Common heuristics, such as electric load following and thermal load following, are the optimal operating strategy under specific conditions. The optimal CHP capacity and operating hours both vary as a function of building type, climate and GHG emissions rates from grid electricity. GHG emissions reductions can be as high as 49% considering a PA fuel cell for a

  1. CRITERIA POLLUTANT EMISSIONS FROM INTERNAL COMBUSTION ENGINES IN THE NATURAL GAS INDUSTRY VOLUME 1. TECHNICAL REPORT

    Science.gov (United States)

    The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...

  2. The U.S. Twin Delivery Volume and Association with Cesarean Delivery Rates: A Hospital-Level Analysis.

    Science.gov (United States)

    Easter, Sarah Rae; Robinson, Julian N; Carusi, Daniela; Little, Sarah E

    2018-03-01

     The objective of this study was to test whether hospitals experienced in twin delivery have lower rates of cesarean delivery for twins.  We divided obstetric hospitals in the 2011 National Inpatient Sample by quartile of annual twin deliveries and compared twin cesarean delivery rates between hospitals with weighted linear regression. We used Pearson's coefficients to correlate a hospital's twin cesarean delivery rate to its overall cesarean delivery and vaginal birth after cesarean (VBAC) rates.  Annual twin delivery volume ranged from 1 to 506 across the 547 analyzed hospitals with a median of 10 and mode of 3. Adjusted rates of cesarean delivery were independent of delivery volume with a rate of 75.5 versus 74.8% in the lowest and highest volume hospitals ( p  = 0.09 across quartiles). A hospital's cesarean delivery rate for twins moderately correlated with the overall cesarean rate ( r  = 0.52, p  < 0.01) and inversely correlated with VBAC rate ( r  =  - 0.42, p  < 0.01).  Most U.S. obstetrical units perform a low volume of twin deliveries with no decrease in cesarean delivery rates at higher volume hospitals. Twin cesarean delivery rates correlate with other obstetric parameters such as singleton cesarean delivery and VBAC rates suggesting twin cesarean delivery rate is more closely related to a hospital's general obstetric practice than its twin delivery volume. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. Estimating volume, biomass, and potential emissions of hand-piled fuels

    Science.gov (United States)

    Clinton S. Wright; Cameron S. Balog; Jeffrey W. Kelly

    2009-01-01

    Dimensions, volume, and biomass were measured for 121 hand-constructed piles composed primarily of coniferous (n = 63) and shrub/hardwood (n = 58) material at sites in Washington and California. Equations using pile dimensions, shape, and type allow users to accurately estimate the biomass of hand piles. Equations for estimating true pile volume from simple geometric...

  4. Survival rate in nasopharyngeal carcinoma improved by high caseload volume: a nationwide population-based study in Taiwan

    International Nuclear Information System (INIS)

    Lee, Ching-Chih; Hung, Shih-Kai; Huang, Tze-Ta; Lee, Moon-Sing; Su, Yu-Chieh; Chou, Pesus; Hsiao, Shih-Hsuan; Chiou, Wen-Yen; Lin, Hon-Yi; Chien, Sou-Hsin

    2011-01-01

    Positive correlation between caseload and outcome has previously been validated for several procedures and cancer treatments. However, there is no information linking caseload and outcome of nasopharyngeal carcinoma (NPC) treatment. We used nationwide population-based data to examine the association between physician case volume and survival rates of patients with NPC. Between 1998 and 2000, a total of 1225 patients were identified from the Taiwan National Health Insurance Research Database. Survival analysis, the Cox proportional hazards model, and propensity score were used to assess the relationship between 10-year survival rates and physician caseloads. As the caseload of individual physicians increased, unadjusted 10-year survival rates increased (p < 0.001). Using a Cox proportional hazard model, patients with NPC treated by high-volume physicians (caseload ≥ 35) had better survival rates (p = 0.001) after adjusting for comorbidities, hospital, and treatment modality. When analyzed by propensity score, the adjusted 10-year survival rate differed significantly between patients treated by high-volume physicians and patients treated by low/medium-volume physicians (75% vs. 61%; p < 0.001). Our data confirm a positive volume-outcome relationship for NPC. After adjusting for differences in the case mix, our analysis found treatment of NPC by high-volume physicians improved 10-year survival rate

  5. Time value of emission and technology discounting rate for off-grid electricity generation in India using intermediate pyrolysis

    International Nuclear Information System (INIS)

    Patel, Amit; Sarkar, Prabir; Tyagi, Himanshu; Singh, Harpreet

    2016-01-01

    The environmental impact assessment of a process over its entire operational lifespan is an important issue. Estimation of life cycle emission helps in predicting the contribution of a given process to abate (or to pollute) the environmental emission scenario. Considering diminishing and time-dependent effect of emission, assessment of the overall effect of emissions is very complex. The paper presents a generalized methodology for arriving at a single emission discounting number for a process option, using the concept of time value of carbon emission flow. This number incorporates the effect of the emission resulting from the process over the entire operational lifespan. The advantage of this method is its quantitative aspect as well as its flexible nature. It can be applied to any process. The method is demonstrated with the help of an Intermediate Pyrolysis process when used to generate off-grid electricity and opting biochar route for disposing straw residue. The scenarios of very high net emission to very high net carbon sequestration is generated using process by careful selection of process parameters for different scenarios. For these different scenarios, the process discounting rate was determined and its outcome is discussed. The paper also proposes a process specific eco-label that mentions the discounting rates. - Highlight: • Methodology to obtain emission discounting rate for a process is proposed. • The method includes all components of life cycle emission converts into a time dependent discounting number. • A case study of Intermediate Pyrolysis is used to obtain such number for a range of processes. • The method is useful to determine if the effect from the operation of a process will lead to a net absorption of emission or net accumulation of emission in the environment.

  6. Time value of emission and technology discounting rate for off-grid electricity generation in India using intermediate pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Amit, E-mail: amitrp@iitrpr.ac.in [Indian Institute of Technology Ropar, Nangal Road, Rupnagar 140001, Punjab (India); Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara 390001, Gujarat (India); Sarkar, Prabir; Tyagi, Himanshu; Singh, Harpreet [Indian Institute of Technology Ropar, Nangal Road, Rupnagar 140001, Punjab (India)

    2016-07-15

    The environmental impact assessment of a process over its entire operational lifespan is an important issue. Estimation of life cycle emission helps in predicting the contribution of a given process to abate (or to pollute) the environmental emission scenario. Considering diminishing and time-dependent effect of emission, assessment of the overall effect of emissions is very complex. The paper presents a generalized methodology for arriving at a single emission discounting number for a process option, using the concept of time value of carbon emission flow. This number incorporates the effect of the emission resulting from the process over the entire operational lifespan. The advantage of this method is its quantitative aspect as well as its flexible nature. It can be applied to any process. The method is demonstrated with the help of an Intermediate Pyrolysis process when used to generate off-grid electricity and opting biochar route for disposing straw residue. The scenarios of very high net emission to very high net carbon sequestration is generated using process by careful selection of process parameters for different scenarios. For these different scenarios, the process discounting rate was determined and its outcome is discussed. The paper also proposes a process specific eco-label that mentions the discounting rates. - Highlight: • Methodology to obtain emission discounting rate for a process is proposed. • The method includes all components of life cycle emission converts into a time dependent discounting number. • A case study of Intermediate Pyrolysis is used to obtain such number for a range of processes. • The method is useful to determine if the effect from the operation of a process will lead to a net absorption of emission or net accumulation of emission in the environment.

  7. Particle emission rates during electrostatic spray deposition of TiO2 nanoparticle-based photoactive coating.

    Science.gov (United States)

    Koivisto, Antti J; Jensen, Alexander C Ø; Kling, Kirsten I; Kling, Jens; Budtz, Hans Christian; Koponen, Ismo K; Tuinman, Ilse; Hussein, Tareq; Jensen, Keld A; Nørgaard, Asger; Levin, Marcus

    2018-01-05

    Here, we studied the particle release rate during Electrostatic spray deposition of anatase-(TiO 2 )-based photoactive coating onto tiles and wallpaper using a commercially available electrostatic spray device. Spraying was performed in a 20.3m 3 test chamber while measuring concentrations of 5.6nm to 31μm-size particles and volatile organic compounds (VOC), as well as particle deposition onto room surfaces and on the spray gun user hand. The particle emission and deposition rates were quantified using aerosol mass balance modelling. The geometric mean particle number emission rate was 1.9×10 10 s -1 and the mean mass emission rate was 381μgs -1 . The respirable mass emission-rate was 65% lower than observed for the entire measured size-range. The mass emission rates were linearly scalable (±ca. 20%) to the process duration. The particle deposition rates were up to 15h -1 for deposited particles consisted of mainly TiO 2 , TiO 2 mixed with Cl and/or Ag, TiO 2 particles coated with carbon, and Ag particles with size ranging from 60nm to ca. 5μm. As expected, no significant VOC emissions were observed as a result of spraying. Finally, we provide recommendations for exposure model parameterization. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  8. Sulfur Dioxide Emission Rates of Kilauea Volcano, Hawaii, 1979-1997

    Science.gov (United States)

    Elias, Tamar; Sutton, A.J.; Stokes, J.B.; Casadevall, T.J.

    1998-01-01

    INTRODUCTION Sulfur dioxide (SO2) emission rates from Kilauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Casadevall and others, 1987; Greenland and others, 1985; Elias and others, 1993; Elias and Sutton, 1996). The purpose of this report is to present a compilation of Kilauea SO2 emission rate data from 1979 through 1997 with ancillary meteorological data (wind speed and wind direction). We have included measurements previously reported by Casadevall and others (1987) for completeness and to improve the usefulness of this current database compilation. Kilauea releases SO2 gas predominantly from its summit caldera and rift zones (fig. 1). From 1979 through 1982, vehicle-based COSPEC measurements made within the summit caldera were adequate to quantify most of the SO2 emitted from the volcano. Beginning in 1983. the focus of SO2 release shifted from the summit to the east rift zone (ERZ) eruption site at Pu'u 'O'o and, later, Kupaianaha. Since 1984, the Kilauea gas measurement effort has been augmented with intermittent airborne and tripod-based surveys made near the ERZ eruption site. In addition, beginning in 1992 vehicle-based measurements have been made along a section of Chain of Craters Road approximately 9 km downwind of the eruption site. These several types of COSPEC measurements continue to the present.

  9. Nitrous oxide emissions from high rate algal ponds treating domestic wastewater.

    Science.gov (United States)

    Alcántara, Cynthia; Muñoz, Raúl; Norvill, Zane; Plouviez, Maxence; Guieysse, Benoit

    2015-02-01

    This study investigated the generation of N2O by microcosms withdrawn from 7-L high rate algal ponds (HRAPs) inoculated with Chlorella vulgaris and treating synthetic wastewater. Although HRAPs microcosms demonstrated the ability to generate algal-mediated N2O when nitrite was externally supplied under darkness in batch assays, negligible N2O emissions rates were consistently recorded in the absence of nitrite during 3.5-month monitoring under 'normal' operation. Thereafter, HRAP A and HRAP B were overloaded with nitrate and ammonium, respectively, in an attempt to stimulate N2O emissions via nitrite in situ accumulation. Significant N2O production (up to 5685±363 nmol N2O/g TSS h) was only recorded from HRAP B microcosms externally supplied with nitrite in darkness. Although confirmation under full-scale outdoors conditions is needed, this study provides the first evidence that the ability of microalgae to synthesize N2O does not affect the environmental performance of wastewater treatment in HRAPs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. NOVAE WITH LONG-LASTING SUPERSOFT EMISSION THAT DRIVE A HIGH ACCRETION RATE

    International Nuclear Information System (INIS)

    Schaefer, Bradley E.; Collazzi, Andrew C.

    2010-01-01

    We identify a new class of novae characterized by the post-eruption quiescent light curve being more than roughly a factor of 10 brighter than the pre-eruption light curve. Eight novae (V723 Cas, V1500 Cyg, V1974 Cyg, GQ Mus, CP Pup, T Pyx, V4633 Sgr, and RW UMi) are separated out as being significantly distinct from other novae. This group shares a suite of uncommon properties, characterized by the post-eruption magnitude being much brighter than before eruption, short orbital periods, long-lasting supersoft emission following the eruption, a highly magnetized white dwarf (WD), and secular declines during the post-eruption quiescence. We present a basic physical picture which shows why all five uncommon properties are causally connected. In general, novae show supersoft emission due to hydrogen burning on the WD in the final portion of the eruption, and this hydrogen burning will be long-lasting if new hydrogen is poured onto the surface at a sufficient rate. Most novae do not have adequate accretion for continuous hydrogen burning, but some can achieve this if the companion star is nearby (with short orbital period) and a magnetic field channels the matter onto a small area on the WD so as to produce a locally high accretion rate. The resultant supersoft flux irradiates the companion star and drives a higher accretion rate (with a brighter post-eruption phase), which serves to keep the hydrogen burning and the supersoft flux going. The feedback loop cannot be perfectly self-sustaining, so the supersoft flux will decline over time, forcing a decline in the accretion rate and the system brightness. We name this new group after the prototype, V1500 Cyg. V1500 Cyg stars are definitely not progenitors of Type Ia supernovae. The V1500 Cyg stars have similar physical mechanisms and appearances as predicted for nova by the hibernation model, but with this group accounting for only 14% of novae.

  11. Estimating the rates of mass change, ice volume change and snow volume change in Greenland from ICESat and GRACE data

    NARCIS (Netherlands)

    Slobbe, D.C.; Ditmar, P.G.; Lindenbergh, R.C.

    2008-01-01

    The focus of this paper is on the quantification of ongoing mass and volume changes over the Greenland ice sheet. For that purpose, we used elevation changes derived from the Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry mission and monthly variations of the Earth’s gravity field

  12. Greenhouse gas emission rate estimates from airborne remote sensing in the short-wave infrared

    Energy Technology Data Exchange (ETDEWEB)

    Krings, Thomas

    2013-01-30

    The quantification of emissions of the greenhouse gases carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) is essential for attributing the roles of anthropogenic activity and natural phenomena in global climate change. The current measurement systems and networks, whilst having improved during the last decades, are deficient in many respects. For example, the emissions from localised and point sources such as fossil fuel exploration sites are not readily assessed. A tool developed to better understand point sources of CO{sub 2} and CH{sub 4} is the optical remote sensing instrument MAMAP, operated from aircraft. With a ground scene size of the order of 50m and a relative accuracy of the column-averaged dry air mole fractions of about 0.3% for XCO{sub 2} and less than 0.4% for XCH{sub 4}, MAMAP can make a significant contribution in this respect. Detailed sensitivity studies showed that the modified WFM-DOAS retrieval algorithm used for MAMAP has an approximate accuracy of about 0.24% for XCH{sub 4} and XCO{sub 2} in typical atmospheric conditions. At the example of CO{sub 2} plumes from two different power plants and CH{sub 4} plumes from coal mine ventilation shafts, two inversion approaches to obtain emission rates were developed and tested. One is based on an optimal estimation scheme to fit Gaussian plume models from multiple sources to the data and the other is based on a simple Gaussian integral method. Compared to CO{sub 2} emission estimates as reported by the power plants' operator within the framework of emission databases (24 and 13 MtCO{sub 2} yr{sup -1}), the results of the individual inversion techniques were within ±10% with uncertainties of ±20-30% mainly due to insufficient wind information and non-stationary atmospheric conditions. Measurements at the coal mine included on-site wind observations by an aircraft turbulence probe that could be utilised to calibrate the wind model. In this case, the inversion results have a bias of less than 1

  13. A pilot study to determine medical laser generated air contaminant emission rates for a simulated surgical procedure.

    Science.gov (United States)

    Lippert, Julia F; Lacey, Steven E; Lopez, Ramon; Franke, John; Conroy, Lorraine; Breskey, John; Esmen, Nurtan; Liu, Li

    2014-01-01

    The U.S. Occupational Safety and Health Administration (OSHA) estimates that half a million health-care workers are exposed to laser surgical smoke each year. The purpose of this study was to establish a methodology to (1) estimate emission rates of laser-generated air contaminants (LGACs) using an emission chamber, and to (2) perform a screening study to differentiate the effects of three laser operational parameters. An emission chamber was designed, fabricated, and assessed for performance to estimate the emission rates of gases and particles associated with LGACs during a simulated surgical procedure. Two medical lasers (Holmium Yttrium Aluminum Garnet [Ho:YAG] and carbon dioxide [CO2]) were set to a range of plausible medical laser operational parameters in a simulated surgery to pyrolyze porcine skin generating plume in the emission chamber. Power, pulse repetition frequency (PRF), and beam diameter were evaluated to determine the effect of each operational parameter on emission rate using a fractional factorial design. The plume was sampled for particulate matter and seven gas phase combustion byproduct contaminants (benzene, ethylbenzene, toluene, formaldehyde, hydrogen cyanide, carbon dioxide, and carbon monoxide): the gas phase emission results are presented here. Most of the measured concentrations of gas phase contaminants were below their limit of detection (LOD), but detectable measurements enabled us to determine laser operation parameter influence on CO2 emissions. Confined to the experimental conditions of this screening study, results indicated that beam diameter was statistically significantly influential and power was marginally statistically significant to emission rates of CO2 when using the Ho:YAG laser but not with the carbon dioxide laser; PRF was not influential vis-a-vis emission rates of these gas phase contaminants.

  14. The Effect of the Volume Flow rate on the Efficiency of a Solar Collector

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    rates. Theoretically, a simplified model of the solar collector panel is built by means of the CFD (Computational Fluid Dynamics) code Fluent, where the geometry of the collector panel except the casing is fully modeled. Both lateral and longitudinal heat conduction in the absorber fins, the heat...... transfer from the absorber to the solar collector fluid and the heat loss from the absorber are considered. Flow and temperature distribution in the collector panel are investigated with buoyancy effect. Measurements are carried out with the solar collector panel. Collector efficiencies are measured......The flow distribution inside a collector panel with an area of 12.5 m² and with 16 parallel connected horizontal fins and the effect of the flow nonuniformity on the risk of boiling and on the collector efficiency have been theoretically and experimentally investigated for different volume flow...

  15. The core collapse supernova rate from 24 years of data of the Large Volume Detector

    Science.gov (United States)

    Bruno, G.; Fulgione, W.; Molinario, A.; Vigorito, C.; LVD Collaboration

    2017-09-01

    The Large Volume Detector (LVD) at INFN Laboratori Nazionali del Gran Sasso, Italy is a 1 kt liquid scintillator neutrino observatory mainly designed to study low energy neutrinos from Gravitational Stellar Collapses (GSC) with 100% efficiency over the entire Galaxy. Here we summarize the results of the search for supernova neutrino bursts over the full data set lasting from June 1992 to May 2016 for a total live time of 8211 days. In the lack of a positive observation, either in standalone mode or in coincidence with other experiments, we establish the upper limit to the rate of GSC event in the Milky Way: 0.1 year-1 at 90% c.l..

  16. Dynamic evolution of the source volumes of gradual and impulsive solar flare emissions

    Science.gov (United States)

    Bruner, M. E.; Crannell, C. J.; Goetz, F.; Magun, A.; Mckenzie, D. L.

    1988-01-01

    This study compares flare source volumes inferred from impulsive hard X-rays and microwaves with those derived from density sensitive soft X-ray line ratios in the O VII spectrum. The data for this study were obtained with the SMM Hard X-ray Burst Spectrometer, Earth-based radio observatories, and the SOLEX-B spectrometer on the P78-1 satellite. Data were available for the flares of 1980 April 8, 1980 May 9, and 1981 February 26. The hard X-ray/microwave source volume is determined under the assumption that the same electron temperature or power law index characterizes both the source of hard X-rays and the source of microwaves. The O VII line ratios yield the density and volume of the 2 x 10 to the 6th K plasma. For all three flares, the O VII source volume is found to be smallest at the beginning of the flare, near the time when the impulsive hard X-ray/microwave volume reaches its first maximum. At this time, the O VII volume is three to four orders of magnitude smaller than that inferred from the hard X-ray/microwave analysis. Subsequently, the O VII source volume increases by one or two orders of magnitude then remains almost constant until the end of the flare when it apparently increases again.

  17. Dynamic evolution of the source volumes of gradual and impulsive solar flare emissions

    International Nuclear Information System (INIS)

    Bruner, M.E.; Crannell, C.J.; Goetz, F.; Magun, A.; Mckenzie, D.L.

    1987-12-01

    This study compares flare source volumes inferred from impulsive hard x rays and microwaves with those derived from density sensitive soft x ray line ratios in the O VII spectrum. The data for this study were obtained with the SMM Hard X-Ray Burst Spectrometer, Earth-based radio observatories, and the SOLEX-B spectrometer on the P78-1 satellite. Data were available for the flares of 1980 April 8, 1980 May 9, and 1981 February 26. The hard x ray/microwave source volume is determined under the assumption that the same electron temperature or power law index characterizes both the source of hard x rays and the source of microwaves. The O VII line ratios yield the density and volume of the 2 X 10 to the 6th K plasma. For all three flares, the O VII source volume is found to be smallest at the beginning of the flare, near the time when the impulsive hard x ray/microwave volume reaches its first maximum. At this time, the O VII volume is three to four orders of magnitude smaller than that inferred from the hard x ray/microwave analysis. Subsequently, the O VII source volume increases by one or two orders of magnitude then remains almost constant until the end of the flare when it apparently increases again

  18. Dynamic evolution of the source volumes of gradual and impulsive solar flare emissions

    International Nuclear Information System (INIS)

    Bruner, M.E.; Crannell, C.J.; Goetz, F.; Magun, A.; Mckenzie, D.L.

    1988-01-01

    This study compares flare source volumes inferred from impulsive hard X-rays and microwaves with those derived from density sensitive soft X-ray line ratios in the O VII spectrum. The data for this study were obtained with the SMM Hard X-ray Burst Spectrometer, Earth-based radio observatories, and the SOLEX-B spectrometer on the P78-1 satellite. Data were available for the flares of 1980 April 8, 1980 May 9, and 1981 February 26. The hard X-ray/microwave source volume is determined under the assumption that the same electron temperature or power law index characterizes both the source of hard X-rays and the source of microwaves. The O VII line ratios yield the density and volume of the 2 x 10 to the 6th K plasma. For all three flares, the O VII source volume is found to be smallest at the beginning of the flare, near the time when the impulsive hard X-ray/microwave volume reaches its first maximum. At this time, the O VII volume is three to four orders of magnitude smaller than that inferred from the hard X-ray/microwave analysis. Subsequently, the O VII source volume increases by one or two orders of magnitude then remains almost constant until the end of the flare when it apparently increases again. 29 references

  19. Carbon emissions and sequestration in forests: Case studies from seven developing countries. Volume 4: Mexico: Draft

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, W.; Sathaye, J. [eds.] [Lawrence Berkeley Lab., CA (United States); Cerutti, O.M.; Ordonez, M.J.; Minjarez, R.D. [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico) Centro de Ecologia

    1992-08-01

    Estimates of carbon emissions from deforestation in Mexico are derived for the year 1985 and for two contrasting scenarios in 2025. Carbon emissions are calculated through an in-depth review of the existing information on forest cover deforestation mtes and area affected by forest fires as well as on forests` carbon-related biological characteristics. The analysis covers both tropical -- evergreen and deciduous -- and temperate -- coniferous and broadleaf -- closed forests. Emissions from the forest sector are also compared to those from energy and industry. Different policy options for promoting the sustainable management of forest resources in the country are discussed. The analysis indicates that approximately 804,000 hectares per year of closed forests suffered from major perturbations in the mid 1980`s in Mexico, leading to an annual deforestation mte of 668,000 hectares. Seventy five percent of total deforestation is concentrated in tropical forests. The resulting annual carbon balance is estimated in 53.4 million tons per year, and the net committed emissions in 45.5 million tons or 41% and 38%, respectively, of the country`s total for 1985--87. The annual carbon balance from the forest sector in 2025 is expected to decline to 16.5 million tons in the low emissions scenario and to 22.9 million tons in the high emissions scenario. Because of the large uncertainties in some of the primary sources of information, the stated figures should be taken as preliminary estimates.

  20. SRC burn test in 700-hp oil-designed boiler. Annex Volume C. Boiler emission report. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    1983-09-01

    The Solvent-Refined Coal (SRC) test burn program was conducted at the Pittsburgh Energy Technology Center (PETC) located in Bruceton, Pa. One of the objectives of the study was to determine the feasibility of burning SRC fuels in boilers set up for fuel oil firing and to characterize emissions. Testing was conducted on the 700-hp oil-fired boiler used for research projects. No. 6 fuel oil was used for baseline data comparison, and the following SRC fuels were tested: SRC Fuel (pulverized SRC), SRC Residual Oil, and SRC-Water Slurry. Uncontrolled particulate emission rates averaged 0.9243 lb/10/sup 6/ Btu for SRC Fuel, 0.1970 lb/10/sup 6/ Btu for SRC Residual Oil, and 0.9085 lb/10/sup 6/ Btu for SRC-Water Slurry. On a lb/10/sup 6/ Btu basis, emissions from SRC Residual Oil averaged 79 and 78%, respectively, lower than the SRC Fuel and SRC-Water Slurry. The lower SRC Residual Oil emissions were due, in part, to the lower ash content of the oil and more efficient combustion. The SRC Fuel had the highest emission rate, but only 2% higher than the SRC-Water Slurry. Each fuel type was tested under variable boiler operating parameters to determine its effect on boiler emissions. The program successfully demonstrated that the SRC fuels could be burned in fuel oil boilers modified to handle SRC fuels. This report details the particulate emission program and results from testing conducted at the boiler outlet located before the mobile precipitator take-off duct. The sampling method was EPA Method 17, which uses an in-stack filter.

  1. Improving and Assessing Aircraft-based Greenhouse Gas Emission Rate Measurements at Indianapolis as part of the INFLUX project.

    Science.gov (United States)

    Heimburger, A. M. F.; Shepson, P. B.; Stirm, B. H.; Susdorf, C.; Cambaliza, M. O. L.

    2015-12-01

    Since the Copenhagen accord in 2009, several countries have affirmed their commitment to reduce their greenhouse gas emissions. The United States and Canada committed to reduce their emissions by 17% below 2005 levels, by 2020, Europe by 14% and China by ~40%. To achieve such targets, coherent and effective strategies in mitigating atmospheric carbon emissions must be implemented in the next decades. Whether such goals are actually achieved, they require that reductions are "measurable", "reportable", and "verifiable". Management of greenhouse gas emissions must focus on urban environments since ~74% of CO2 emissions worldwide will be from cities, while measurement approaches are highly uncertain (~50% to >100%). The Indianapolis Flux Experiment (INFLUX) was established to develop, assess and improve top-down and bottom-up quantifications of urban greenhouse gas emissions. Based on an aircraft mass balance approach, we performed a series of experiments focused on the improvement of CO2, CH4 and CO emission rates quantification from Indianapolis, our final objective being to drastically improve the method overall uncertainty from the previous estimate of 50%. In November-December 2014, we conducted nine methodologically identical mass balance experiments in a short period of time (24 days, one downwind distance) for assumed constant total emission rate conditions, as a means to obtain an improved standard deviation of the mean determination. By averaging the individual emission rate determinations, we were able to obtain a method precision of 17% and 16% for CO2 and CO, respectively, at the 95%C.L. CH4 emission rates are highly variable day to day, leading to precision of 60%. Our results show that repetitive sampling can enable improvement in precision of the aircraft top-down methods through averaging.

  2. 640-slice DVCT multi-dimensionally and dynamically presents changes in bladder volume and urine flow rate

    Science.gov (United States)

    Su, Yunshan; Fang, Kewei; Mao, Chongwen; Xiang, Shutian; Wang, Jin; Li, Yingwen

    2018-01-01

    The present study aimed to explore the application of 640-slice dynamic volume computed tomography (DVCT) to excretory cystography and urethrography. A total of 70 healthy subjects were included in the study. Excretory cystography and urethrography using 640-slice DVCT was conducted to continuously record the motions of the bladder and the proximal female and male urethra. The patients' voiding process was divided into early, early to middle, middle, middle to late, and late voiding phases. The subjects were analyzed using DVCT and conventional CT. The cross-sectional areas of various sections of the male and female urethra were evaluated, and the average urine flow rate was calculated. The 640-slice DVCT technique was used to dynamically observe the urine flow rate and changes in bladder volume at all voiding phases. The urine volume detected by 640-slice DVCT exhibited no significant difference compared with the actual volume, and no significant difference compared with that determined using conventional CT. Furthermore, no significant difference in the volume of the bladder at each phase of the voiding process was detected between 640-slice DVCT and conventional CT. The results indicate that 640-slice DVCT can accurately evaluate the status of the male posterior urethra and female urethra. In conclusion, 640-slice DVCT is able to multi-dimensionally and dynamically present changes in bladder volume and urine flow rate, and could obtain similar results to conventional CT in detecting urine volume, as well as the status of the male posterior urethra and female urethra. PMID:29467853

  3. Estimation of methane emission rate changes using age-defined waste in a landfill site.

    Science.gov (United States)

    Ishii, Kazuei; Furuichi, Toru

    2013-09-01

    Long term methane emissions from landfill sites are often predicted by first-order decay (FOD) models, in which the default coefficients of the methane generation potential and the methane generation rate given by the Intergovernmental Panel on Climate Change (IPCC) are usually used. However, previous studies have demonstrated the large uncertainty in these coefficients because they are derived from a calibration procedure under ideal steady-state conditions, not actual landfill site conditions. In this study, the coefficients in the FOD model were estimated by a new approach to predict more precise long term methane generation by considering region-specific conditions. In the new approach, age-defined waste samples, which had been under the actual landfill site conditions, were collected in Hokkaido, Japan (in cold region), and the time series data on the age-defined waste sample's methane generation potential was used to estimate the coefficients in the FOD model. The degradation coefficients were 0.0501/y and 0.0621/y for paper and food waste, and the methane generation potentials were 214.4 mL/g-wet waste and 126.7 mL/g-wet waste for paper and food waste, respectively. These coefficients were compared with the default coefficients given by the IPCC. Although the degradation coefficient for food waste was smaller than the default value, the other coefficients were within the range of the default coefficients. With these new coefficients to calculate methane generation, the long term methane emissions from the landfill site was estimated at 1.35×10(4)m(3)-CH(4), which corresponds to approximately 2.53% of the total carbon dioxide emissions in the city (5.34×10(5)t-CO(2)/y). Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Reirradiation of Large-Volume Recurrent Glioma With Pulsed Reduced-Dose-Rate Radiotherapy

    International Nuclear Information System (INIS)

    Adkison, Jarrod B.; Tome, Wolfgang; Seo, Songwon; Richards, Gregory M.; Robins, H. Ian; Rassmussen, Karl; Welsh, James S.; Mahler, Peter A.; Howard, Steven P.

    2011-01-01

    Purpose: Pulsed reduced-dose-rate radiotherapy (PRDR) is a reirradiation technique that reduces the effective dose rate and increases the treatment time, allowing sublethal damage repair during irradiation. Patients and Methods: A total of 103 patients with recurrent glioma underwent reirradiation using PRDR (86 considered to have Grade 4 at PRDR). PRDR was delivered using a series of 0.2-Gy pulses at 3-min intervals, creating an apparent dose rate of 0.0667 Gy/min to a median dose of 50 Gy (range, 20-60) delivered in 1.8-2.0-Gy fractions. The mean treatment volume was 403.5 ± 189.4 cm 3 according to T 2 -weighted magnetic resonance imaging and a 2-cm margin. Results: For the initial or upgraded Grade 4 cohort (n = 86), the median interval from the first irradiation to PRDR was 14 months. Patients undergoing PRDR within 14 months of the first irradiation (n = 43) had a median survival of 21 weeks. Those treated ≥14 months after radiotherapy had a median survival of 28 weeks (n = 43; p = 0.004 and HR = 1.82 with a 95% CI ranging from 1.25 to 3.10). These data compared favorably to historical data sets, because only 16% of the patients were treated at first relapse (with 46% treated at the second relapse, 32% at the third or fourth relapse, and 4% at the fourth or fifth relapse). The median survival since diagnosis and retreatment was 6.3 years and 11.4 months for low-grade, 4.1 years and 5.6 months for Grade 3, and 1.6 years and 5.1 months for Grade 4 tumors, respectively, according to the initial histologic findings. Multivariate analysis revealed age at the initial diagnosis, initial low-grade disease, and Karnofsky performance score of ≥80 to be significant predictors of survival after initiation of PRDR. Conclusion: PRDR allowed for safe retreatment of larger volumes to high doses with palliative benefit.

  5. Determination of disintegration rates of a 60Co point source and volume sources by the sum-peak method

    International Nuclear Information System (INIS)

    Kawano, Takao; Ebihara, Hiroshi

    1990-01-01

    The disintegration rates of 60 Co as a point source (<2 mm in diameter on a thin plastic disc) and volume sources (10-100 mL solutions in a polyethylene bottle) are determined by the sum-peak method. The sum-peak formula gives the exact disintegration rate for the point source at different positions from the detector. However, increasing the volume of the solution results in enlarged deviations from the true disintegration rate. Extended sources must be treated as an amalgam of many point sources. (author)

  6. LERFCM: a computer code for spatial reconstruction of volume emission from chord measurements in plasmas

    International Nuclear Information System (INIS)

    Navarro, A.P.; Pare, V.K.; Dunlap, J.L.

    1981-01-01

    Local Emissivity Reconstruction from Chord Measurements (LERFCM) is a package of computer programs used to determine the two-dimensional spatial distribution of the emission intensity of radiation in a plasma from line integral data, which represents signals from arrays of collimated detectors looking through the plasma along different chords in a plane. The method requires data from only a few detector arrays and assumes that the emission distribution in the plane of observation has a smooth angular dependence that can be represented by a few low-order harmonics. The intended application is a reconstruction of plasma shape and MHD instabilities, using data from arrays of soft x-ray detectors on Impurity Study Experiment Tokamak

  7. In vivo imaging of GABA{sub A} receptors using sequential whole-volume iodine-123 iomazenil single-photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Busatto, G.F. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom); Pilowsky, L.S. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom); Costa, D.C. [Inst. of Nuclear Medicine, University Coll. and Middlesex School of Medicine, London (United Kingdom); Ell, P.J. [Inst. of Nuclear Medicine, University Coll. and Middlesex School of Medicine, London (United Kingdom); Lingford-Hughes, A. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom); Kerwin, R.W. [Dept. of Psychological Medicine, Inst. of Psychiatry, London (United Kingdom)

    1995-01-01

    Using a brain-dedicated triple-headed single-photon emission tomography (SPET) system, a sequential whole-volume imaging protocol has been devised to evaluate the regional distribution of iodine-123 iomazenil binding to GABA{sub A} receptors in the entire brain. The protocol was piloted in eight normal volunteers (seven males and one female; mean age, 24.8{+-}3.9 years). The patterns obtained were largely compatible with the known distribution of GABA{sub A} receptors in the brain as reported in autoradiographic studies, with cerebral cortical regions, particularly the occipital and frontal cortices, displaying the highest {sup 123}I-iomazenil uptake. Measures of time to peak uptake and tracer washout rates presented with the same pattern of regional variation, with later times to peak and slower washout rates in cortical regions compared to other brain areas. Semiquantitative analysis of the data using white matter/ventricle regions as reference demonstrated a plateau of specific {sup 123}I-iomazenil binding in neocortical and cerebellar regions from 60-75 min onwards. These data demonstrate the feasibility of sequential, dynamic whole-volume {sup 123}I-iomazenil SPET imaging. The protocol may be particularly useful in the investigation of neuropsychiatric conditions which are likely to involve more than one focus of GABA abnormalities, such as anxiety disorders and schizophrenia. (orig.)

  8. Surface and volume photoemission of hot electrons from plasmonic nanoantennas

    DEFF Research Database (Denmark)

    Uskov, Alexander V.; Protsenko, Igor E.; Ikhsanov, Renat S.

    2014-01-01

    We theoretically compare surface- and volume-based photoelectron emission from spherical nanoparticles, obtaining analytical expressions for the emission rate in both mechanisms. We show that the surface mechanism prevails, being unaffected by detrimental hot electron collisions.......We theoretically compare surface- and volume-based photoelectron emission from spherical nanoparticles, obtaining analytical expressions for the emission rate in both mechanisms. We show that the surface mechanism prevails, being unaffected by detrimental hot electron collisions....

  9. Preliminary results of rocket attitude and auroral green line emission rate in the DELTA campaign

    Science.gov (United States)

    Iwagami, Naomoto; Komada, Sayaka; Takahashi, Takao

    2006-09-01

    The attitude of a sounding rocket launched in the DELTA (Dynamics and Energetics of the Lower Thermosphere in Aurora) campaign was determined with IR horizon sensors and geomagnetic sensors. Since the payload was separated into two portions, two sets of attitude sensors were needed. A new IR sensor was developed for the present experiment, and found the zenith-angle of the spin-axis of the rocket with an accuracy of 2°. By combining information obtained by both type of sensors, the absolute attitudes were determined. The auroral green line emission rate was measured by a photometer on board the same rocket launched under active auroral conditions, and the energy flux of the auroral particle precipitation was estimated.

  10. Particulate metals and organic compounds from electronic and tobacco-containing cigarettes: comparison of emission rates and secondhand exposure.

    Science.gov (United States)

    Saffari, Arian; Daher, Nancy; Ruprecht, Ario; De Marco, Cinzia; Pozzi, Paolo; Boffi, Roberto; Hamad, Samera H; Shafer, Martin M; Schauer, James J; Westerdahl, Dane; Sioutas, Constantinos

    2014-01-01

    In recent years, electronic cigarettes have gained increasing popularity as alternatives to normal (tobacco-containing) cigarettes. In the present study, particles generated by e-cigarettes and normal cigarettes have been analyzed and the degree of exposure to different chemical agents and their emission rates were quantified. Despite the 10-fold decrease in the total exposure to particulate elements in e-cigarettes compared to normal cigarettes, specific metals (e.g. Ni and Ag) still displayed a higher emission rate from e-cigarettes. Further analysis indicated that the contribution of e-liquid to the emission of these metals is rather minimal, implying that they likely originate from other components of the e-cigarette device or other indoor sources. Organic species had lower emission rates during e-cigarette consumption compared to normal cigarettes. Of particular note was the non-detectable emission of polycyclic aromatic hydrocarbons (PAHs) from e-cigarettes, while substantial emission of these species was observed from normal cigarettes. Overall, with the exception of Ni, Zn, and Ag, the consumption of e-cigarettes resulted in a remarkable decrease in secondhand exposure to all metals and organic compounds. Implementing quality control protocols on the manufacture of e-cigarettes would further minimize the emission of metals from these devices and improve their safety and associated health effects.

  11. Clinical investigations on the use of positron emission tomography (PET) for target volume definition in radiation therapy planning; Klinische Untersuchungen zum Einsatz der Positronen-Emissions-Tomographie (PET) in der Zielvolumendefinition bei der Bestrahlungsplanung

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Ingo G.

    2014-12-05

    The aim of the present study was to evaluate the clinical value of positron emission tomography (PET) for target volume definition in different tumor entities using different tracers and taking pretreatment of patients into account. The study collective comprised 109 patients with 112 target volumes. In 48 patients with skull base meningiomas (SBM) and 42 patients with meningiomas of other localizations (SOM) undergoing fractionated stereotactic radiation therapy the gross tumor volumes (SBM, n=48; SOM, n=39) based on magnetic resonance imaging/computed tomography (MRI/CT) and {sup 68}Ga-DOTATOC-PET were compared retrospectively. Additionally, in 19 patients with liver metastasis from colorectal cancer (LM-CRC) treated in 25 CT guided brachytherapy sessions the clinical target volumes (CTV) either based on MRI/CT or {sup 18}F-FDG-PET were compared retrospectively. The spatial agreement of the target volumes was analyzed using the Dice similarity coefficient (DSC). The association of DSC, tumor entity and pretreatment was analyzed using the general linear model (GLM). Metric parameters are given as median (25th/75th-quartile). In the complete patient sample the PET based target volume was 24.1 (10.8/51.2) ml and, thus, significantly (p<0.001) increased by 18.9% (-3.6%/62.7%) compared to the MRI/CT based target volume of 20.8 (8.6/45.0) ml. In the subgroup of LM-CRC, the PET based target volume was significantly increased by 24.4% (0%/ 71.4%; p=0.021), and in patients with SBM it was increased by 23.9%(-1.7%/65.7%; p=0.003) whereas in SOM the difference of 8.0% (-3.6%/51.7%; p=0.199) was not significant. The DSC for PET and MRI/CT based target volumes was 0.66 (0.46/0.76) in the whole study group and varied between 0.65 (0.46/0.71) in patients with SBM and 0.70 (0.40/0.79) in patients with SOM. In pre-treated patients with LM-CRC a significant lower DSC of 0.62 (0.41/0.66) was observed in comparison to 0.84 (0.70/0.96) in untreated patients (significant interaction

  12. Survival rate in nasopharyngeal carcinoma improved by high caseload volume: a nationwide population-based study in Taiwan

    Directory of Open Access Journals (Sweden)

    Chou Pesus

    2011-08-01

    Full Text Available Abstract Background Positive correlation between caseload and outcome has previously been validated for several procedures and cancer treatments. However, there is no information linking caseload and outcome of nasopharyngeal carcinoma (NPC treatment. We used nationwide population-based data to examine the association between physician case volume and survival rates of patients with NPC. Methods Between 1998 and 2000, a total of 1225 patients were identified from the Taiwan National Health Insurance Research Database. Survival analysis, the Cox proportional hazards model, and propensity score were used to assess the relationship between 10-year survival rates and physician caseloads. Results As the caseload of individual physicians increased, unadjusted 10-year survival rates increased (p p = 0.001 after adjusting for comorbidities, hospital, and treatment modality. When analyzed by propensity score, the adjusted 10-year survival rate differed significantly between patients treated by high-volume physicians and patients treated by low/medium-volume physicians (75% vs. 61%; p Conclusions Our data confirm a positive volume-outcome relationship for NPC. After adjusting for differences in the case mix, our analysis found treatment of NPC by high-volume physicians improved 10-year survival rate.

  13. Carbon emissions, logistics volume and GDP in China: empirical analysis based on panel data model.

    Science.gov (United States)

    Guo, Xiaopeng; Ren, Dongfang; Shi, Jiaxing

    2016-12-01

    This paper studies the relationship among carbon emissions, GDP, and logistics by using a panel data model and a combination of statistics and econometrics theory. The model is based on the historical data of 10 typical provinces and cities in China during 2005-2014. The model in this paper adds the variability of logistics on the basis of previous studies, and this variable is replaced by the freight turnover of the provinces. Carbon emissions are calculated by using the annual consumption of coal, oil, and natural gas. GDP is the gross domestic product. The results showed that the amount of logistics and GDP have a contribution to carbon emissions and the long-term relationships are different between different cities in China, mainly influenced by the difference among development mode, economic structure, and level of logistic development. After the testing of panel model setting, this paper established a variable coefficient model of the panel. The influence of GDP and logistics on carbon emissions is obtained according to the influence factors among the variables. The paper concludes with main findings and provides recommendations toward rational planning of urban sustainable development and environmental protection for China.

  14. Narrow band flame emission from dieseline and diesel spray combustion in a constant volume combustion chamber

    KAUST Repository

    Wu, Zengyang; Jing, Wei; Zhang, Weibo; Roberts, William L.; Fang, Tiegang

    2016-01-01

    emissions were studied. Ambient oxygen concentration was varied from 12% to 21% and three ambient temperatures were selected: 800 K, 1000 K and 1200 K. An intensified CCD camera coupled with bandpass filters was employed to capture the quasi-steady state

  15. FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS VOLUME III. FIELD EVALUATIONS

    Science.gov (United States)

    The report gives results of field tests conducted to determine the emission characteristics of a Babcock and Wilcox Circular burner and Dual Register burner (DRB). The field tests were performed at two utility boilers, generally comparable in design and size except for the burner...

  16. CHARACTERIZATION OF MERCURY EMISSIONS AT A CHLOR-ALKALI PLANT, VOLUME II. APPENDICES F-J

    Science.gov (United States)

    The report gives results of a characterization of mercury (Hg) emissions at a chlor-alkali plant. Up to 160 short tons (146 Mg) of Hg is consumed by the chlor-alkali industry each year. Very little quantitative information is currently available however, on the actual Hg losses f...

  17. Development of a direct measurement system for the standardization of neutron emission rates

    International Nuclear Information System (INIS)

    Ogheard, Florestan

    2012-01-01

    The manganese bath technique is the reference method for neutron source emission rates calibration. It is used to calibrate neutron sources using radionuclides (AmBe, PuBe, "2"5"2Cf,...) in terms of neutron emission rate under 4π sr. As a complement to this technique, the anisotropy of the source is measured using a rotating source holder and a neutron long counter. The neutron source to be measured is immersed in a manganese sulphate solution whereby the emitted neutrons are captured within the bath contents. In a typical configuration (a 1 m diameter sphere and a concentrated solution), approximately half of the neutrons lead to the creation of "5"6Mn via the "5"5Mn(n, γ) capture reaction. The "5"6Mn radionuclide has a half-life of approximately 2.6 hours and the bath reaches saturation when the number of nuclei decaying is equal to the number of nuclei created per unit time. The neutron emission rate from the source can then be deduced from the "5"6Mn activity at saturation, assuming proper modelling of the nuclear reactions occurring in the bath. The manganese bath facility at LNE-LNHB has been recently refurbished in order to comply with appropriate safety and radioprotection regulations. This has lead to the upgrading of both the measurement methodology and the modelling of the bath, and a study on the development of a new detector for the on-line measurement of the manganese activity was started. This new detector uses the β-γ coincidence measurement method. The beta channel consists of two photomultipliers tubes which allow the detection of Cerenkov light, and the gamma channel uses a solid scintillation detector. The advantage of this measurement method is that it allows the determination of the bath activity without any prior calibration, unlike the former method which uses a gamma-ray detector calibrated using a high activity manganese source. The principle of the Cerenkov-gamma coincidence measurement has been validated by a prototype of the

  18. Exploring a suitable nitrogen fertilizer rate to reduce greenhouse gas emissions and ensure rice yields in paddy fields

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Yiming; Wang, Xiaopeng; Yang, Jingping, E-mail: jpyang@zju.edu.cn; Zhao, Xing; Ye, Xinyi

    2016-09-15

    The application rate of nitrogen fertilizer was believed to dramatically influence greenhouse gas (GHG) emissions from paddy fields. Thus, providing a suitable nitrogen fertilization rate to ensure rice yields, reducing GHG emissions and exploring emission behavior are important issues for field management. In this paper, a two year experiment with six rates (0, 75, 150, 225, 300, 375 kg N/ha) of nitrogen fertilizer application was designed to examine GHG emissions by measuring carbon dioxide (CO{sub 2}), methane (CH{sub 4}), nitrous oxide (N{sub 2}O) flux and their cumulative global warming potential (GWP) from paddy fields in Hangzhou, Zhejiang in 2013 and 2014. The results indicated that the GWP and rice yields increased with an increasing application rate of nitrogen fertilizer. Emission peaks of CH{sub 4} mainly appeared at the vegetative phase, and emission peaks of CO{sub 2}, and N{sub 2}O mainly appeared at reproductive phase of rice growth. The CO{sub 2} flux was significantly correlated with soil temperature, while the CH{sub 4} flux was influenced by logging water remaining period and N{sub 2}O flux was significantly associated with nitrogen application rates. This study showed that 225 kg N/ha was a suitable nitrogen fertilizer rate to minimize GHG emissions with low yield-scaled emissions of 3.69 (in 2013) and 2.23 (in 2014) kg CO{sub 2}-eq/kg rice yield as well as to ensure rice yields remained at a relatively high level of 8.89 t/ha in paddy fields. - Highlights: • Exploiting co-benefits of rice yield and reduction of greenhouse gas emission. • Global warming potential and rice yield increased with nitrogen fertilizer rate up. • Emission peaks of CH{sub 4,} CO{sub 2} and N{sub 2}O appeared at vegetative and reproductive phase. • 225 kg N/ha rate benefits both rice yields and GWP reduction.

  19. Cerebral blood volume measurement using radioactive carboxyhemoglobin and positron emission tomography. Chapter 26

    International Nuclear Information System (INIS)

    Kanno, Iwao; Murakami, Matsutaro; Miura, Shuichi; Iida, Hidehiro; Takahashi, Kazuhiro; Sasaki, Hiroshi; Uemura, Kazuo

    1988-01-01

    This paper aims to describe the technical basis for this simplest cerebral blood volume (CBV) measurement using CO-labelled red blood cells and PET and to clarify the error sources in the technique which will become critical when we perform studies on physiological activation of CBV. 17 refs.; 6 figs.; 2 tabs

  20. Twenty-fold plasmon-induced enhancement of radiative emission rate in silicon nanocrystals embedded in silicon dioxide

    International Nuclear Information System (INIS)

    Gardelis, S; Gianneta, V.; Nassiopoulou, A.G

    2016-01-01

    We report on a 20-fold enhancement of the integrated photoluminescence (PL) emission of silicon nanocrystals, embedded in a matrix of silicon dioxide, induced by excited surface plasmons from silver nanoparticles, which are located in the vicinity of the silicon nanocrystals and separated from them by a silicon dioxide layer of a few nanometers. The electric field enhancement provided by the excited surface plasmons increases the absorption cross section and the emission rate of the nearby silicon nanocrystals, resulting in the observed enhancement of the photoluminescence, mainly attributed to a 20-fold enhancement in the emission rate of the silicon nanocrystals. The observed remarkable improvement of the PL emission makes silicon nanocrystals very useful material for photonic, sensor and solar cell applications.

  1. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    International Nuclear Information System (INIS)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman; Tolunay, Doganay; Odabasi, Mustafa; Elbir, Tolga

    2014-01-01

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO 2 ) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m 2 s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and

  2. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Tolunay, Doganay [Department of Soil Science and Ecology, Faculty of Forestry, Istanbul University, Bahcekoy, Istanbul (Turkey); Odabasi, Mustafa [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Elbir, Tolga, E-mail: tolga.elbir@deu.edu.tr [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey)

    2014-08-15

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO{sub 2}) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m{sup 2} s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta

  3. Determination of the emission rate for the 14 MeV neutron generator with the use of radio-yttrium

    OpenAIRE

    Laszynska Ewa; Jednorog Slawomir; Ziolkowski Adam; Gierlik Michal; Rzadkiewicz Jacek

    2015-01-01

    The neutron emission rate is a crucial parameter for most of the radiation sources that emit neutrons. In the case of large fusion devices the determination of this parameter is necessary for a proper assessment of the power release and the prediction for the neutron budget. The 14 MeV neutron generator will be used for calibration of neutron diagnostics at JET and ITER facilities. The stability of the neutron generator working parameters like emission and angular homogeneity affects the accu...

  4. Assessing the optimized precision of the aircraft mass balance method for measurement of urban greenhouse gas emission rates through averaging

    Directory of Open Access Journals (Sweden)

    Alexie M. F. Heimburger

    2017-06-01

    Full Text Available To effectively address climate change, aggressive mitigation policies need to be implemented to reduce greenhouse gas emissions. Anthropogenic carbon emissions are mostly generated from urban environments, where human activities are spatially concentrated. Improvements in uncertainty determinations and precision of measurement techniques are critical to permit accurate and precise tracking of emissions changes relative to the reduction targets. As part of the INFLUX project, we quantified carbon dioxide (CO2, carbon monoxide (CO and methane (CH4 emission rates for the city of Indianapolis by averaging results from nine aircraft-based mass balance experiments performed in November-December 2014. Our goal was to assess the achievable precision of the aircraft-based mass balance method through averaging, assuming constant CO2, CH4 and CO emissions during a three-week field campaign in late fall. The averaging method leads to an emission rate of 14,600 mol/s for CO2, assumed to be largely fossil-derived for this period of the year, and 108 mol/s for CO. The relative standard error of the mean is 17% and 16%, for CO2 and CO, respectively, at the 95% confidence level (CL, i.e. a more than 2-fold improvement from the previous estimate of ~40% for single-flight measurements for Indianapolis. For CH4, the averaged emission rate is 67 mol/s, while the standard error of the mean at 95% CL is large, i.e. ±60%. Given the results for CO2 and CO for the same flight data, we conclude that this much larger scatter in the observed CH4 emission rate is most likely due to variability of CH4 emissions, suggesting that the assumption of constant daily emissions is not correct for CH4 sources. This work shows that repeated measurements using aircraft-based mass balance methods can yield sufficient precision of the mean to inform emissions reduction efforts by detecting changes over time in urban emissions.

  5. Pulse shaping for high data rate ultra-wideband wireless transmission under the Russian spectral emission mask

    DEFF Research Database (Denmark)

    Rommel, Simon; Grakhova, Elizaveta P.; Jurado-Navas, Antonio

    2017-01-01

    This paper addresses impulse-radio ultra-wideband (IR-UWB) transmission under the Russian spectral emission mask for unlicensed UWB radio communications. Four pulse shapes are proposed and their bit error rate (BER) performance is both estimated analytically and evaluated experimentally. Well......-known shapes such as the Gaussian, root-raised cosine, hyperbolic secant, and the frequency B-spline wavelet are used to form linear combinations of component pulses, shaped to make efficient use of the spectral emission mask. Analytical BER values are derived using a Nakagami-m model, and good agreement......-UWB transmission under the strict regulations of the Russian spectral emission mask....

  6. EU Energy Law. Volume 4. The EU Greenhouse Gas Emissions Trading Scheme

    International Nuclear Information System (INIS)

    Delbeke, J.; Hartridge, O.; Lefevere, J.; Meadows, D.; Runge-Metzger, A.; Slingenberg, Y.; Vainio, M.; Vis, P.; Zapfel, P.

    2006-06-01

    Gives valuable insights in the why's, how's, trade-offs, and critical design choices of the Emission Trading System of the European Union (EU ETS). The chapters deal with (1) The EU ETS: the result of a decade of policy action on the economic dimension of EU environmental policy; (2) The international climate policy developments of the 1990s: UNFCCC, the Kyoto Protocol, the Marrakech Agreements and the EU's Kyoto ratification decision; (3) Emissions trading: What is it? Design options and misconceptions; (4) The EU ETS Directive 2003/87/EEC explained; (5) The EU ETS Linking Directive explained; (6) The economic efficiency benefits of the EU ETS; (7) The NAP I experience; (8) The key importance of the Registry Regulation and of solid monitoring and verification; and (9) The potential role of the EU ETS for the elaboration of the post-2012 international climate regime. Conclusions are in chapter 10

  7. Does the pancreatic volume reduction rate using serial computed tomographic volumetry predict new onset diabetes after pancreaticoduodenectomy?

    Science.gov (United States)

    Yun, Sung Pil; Seo, Hyung-Il; Kim, Suk; Kim, Dong Uk; Baek, Dong Hoon

    2017-01-01

    Abstract Volume reduction of the pancreatic tissues following a pancreatectomy can lead to the deterioration of glucose homeostasis. This is defined as pancreatogenic diabetes mellitus (DM). The objective of this study was to investigate the occurrence of new-onset DM (NODM) and evaluate the risk factors, including the pancreas volume reduction rate in patients undergoing pancreaticoduodenectomy (PD). Sixty-six patients without preoperative DM underwent PD for periampullary tumors between August 2007 and December 2012 and were included in this analysis. These patients underwent follow-up tests and abdominal computed tomography (CT) scan 7 days, 6 months, 12 months, 24 months, and 36 months after the operation. The pancreas volume reduction rate was calculated by CT volumetry. The patients were divided into 2 groups according to the postoperative development of DM. After PD, newly diagnosed DM occurred in 16 patients (24.2%). The incidence of DM was highest among patients with carcinomas with an advanced T stage. The pancreatic volume reduction rate after 6 and 12 months in the NODM group was significantly higher than the normal glucose group in the univariate analysis. In the multivariate analysis, the pancreatic volume reduction rate 6 months after PD was the only significant predictive factor for the development of NODM (P = 0.002). This study suggests that the pancreatic volume reduction rate 6 months after PD was the only significant predictive factor for the development of NODM. CT volumetry of the pancreas may be useful as a predictor of NODM after PD. PMID:28353594

  8. Quantifying rate of deforestation and CO2 emission in Peninsular Malaysia using Palsar imageries

    Science.gov (United States)

    Hamdan, O.; Abd Rahman, K.; Samsudin, M.

    2016-06-01

    Increasing human population and the rapid growth of Malaysia's economy are often associated with various environmental disturbances which have been contributing to depletion of natural resources and climate change. The need for more spaces for numerous land development activities has made the existing forests suffer deforestation. The study was carried out in Peninsular Malaysia, which currently has about 5.9 million ha of forests. Phased array type L-band SAR (Palsar) and Palsar-2 images over the years 2010 and 2015, respectively were used to identify forest cover and deforestation occurrences resulted from various conversion of forests to other land uses. Forests have been identified from horizontal-vertical (HV) polarization and then classified into three major categories, which are inland, peat swamp and mangrove. Pixel subtraction technique was used to determine areas that have been changing from forests to other land uses. Forest areas have been found declined from about 6.1 million ha in year 2010 to some 5.9 million ha in 2015 due to conversion of forests to other land uses. Causes of deforestation have been identified and the amount of carbon dioxide (CO2) that has been emitted due to the deforestation activity has been determined in this study. Oil palm and rubber plantations expansion has been found the most prominent factor that caused deforestation in Peninsular Malaysia, especially in the states of Pahang, Terengganu, Johor and Kelantan. The rate of deforestation in the period was at 0.66% yr-1, which amounted a total of about 200,225 ha over the five years. Carbon loss was estimated at about 30.2 million Mg C, which has resulted in CO2 emission accounted at about 110.6 million Mg CO2. The rate of CO2 emission that has been resulted from deforestation was estimated at 22.1 million Mg CO2 yr-1. The study found that the use of a series of Palsar and Palsar-2 images, with a consistent, cloud-free images, are the most appropriate sensors to be used for

  9. A numerical study of the effects of injection rate shape on combustion and emission of diesel engines

    Directory of Open Access Journals (Sweden)

    He Zhixia

    2014-01-01

    Full Text Available The spray characteristics including spray droplet sizes, droplet distribution, spray tip penetration length and spray diffusion angle directly affects the mixture process of fuel and oxygen and then plays an important role for the improvement of combustion and emission performance of diesel engines. Different injection rate shapes may induce different spray characteristics and then further affect the subsequent combustion and emission performance of diesel engines. In this paper, the spray and combustion processes based on four different injection rate shapes with constant injection duration and injected fuel mass were simulated in the software of AVL FIRE. The numerical models were validated through comparing the results from the simulation with those from experiment. It was found that the dynamic of diesel engines with the new proposed hump shape of injection rate and the original saddle shape is better than that with the injection rate of rectangle and triangle shape, but the emission of NOX is higher. And the soot emission is lowest during the late injection period for the new hump-shape injection rate because of a higher oxidation rate with a better mixture between fuel and air under the high injection pressure.

  10. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: determination of specific emission rates for thirty-one tree species.

    Science.gov (United States)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman; Tolunay, Doganay; Odabasi, Mustafa; Elbir, Tolga

    2014-08-15

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO2) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m(2)s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/gh was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/gh. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and beta

  11. Quantification of Greenhouse Gas Emission Rates from strong Point Sources by Airborne IPDA-Lidar Measurements: Methodology and Experimental Results

    Science.gov (United States)

    Ehret, G.; Amediek, A.; Wirth, M.; Fix, A.; Kiemle, C.; Quatrevalet, M.

    2016-12-01

    We report on a new method and on the first demonstration to quantify emission rates from strong greenhouse gas (GHG) point sources using airborne Integrated Path Differential Absorption (IPDA) Lidar measurements. In order to build trust in the self-reported emission rates by countries, verification against independent monitoring systems is a prerequisite to check the reported budget. A significant fraction of the total anthropogenic emission of CO2 and CH4 originates from localized strong point sources of large energy production sites or landfills. Both are not monitored with sufficiently accuracy by the current observation system. There is a debate whether airborne remote sensing could fill in the gap to infer those emission rates from budgeting or from Gaussian plume inversion approaches, whereby measurements of the GHG column abundance beneath the aircraft can be used to constrain inverse models. In contrast to passive sensors, the use of an active instrument like CHARM-F for such emission verification measurements is new. CHARM-F is a new airborne IPDA-Lidar devised for the German research aircraft HALO for the simultaneous measurement of the column-integrated dry-air mixing ratio of CO2 and CH4 commonly denoted as XCO2 und XCH4, respectively. It has successfully been tested in a serious of flights over Central Europe to assess its performance under various reflectivity conditions and in a strongly varying topography like the Alps. The analysis of a methane plume measured in crosswind direction of a coal mine ventilation shaft revealed an instantaneous emission rate of 9.9 ± 1.7 kt CH4 yr-1. We discuss the methodology of our point source estimation approach and give an outlook on the CoMet field experiment scheduled in 2017 for the measurement of anthropogenic and natural GHG emissions by a combination of active and passive remote sensing instruments on research aircraft.

  12. Dynamics, OH distributions and UV emission of a gliding arc at various flow-rates investigated by optical measurements

    DEFF Research Database (Denmark)

    Zhu, Jiajian; Sun, Zhiwei; Li, Zhongshan

    2014-01-01

    -state OH were investigated using planar laser-induced fluorescence. The results show that the shape, height, intensity and thickness of ground-state OH distribution vary significantly with air flow rates. Finally, UV emission of the gliding arc is measured using optical emission spectroscopy......We demonstrate a plasma discharge which is generated between two diverging electrodes and extended into a gliding arc in non-equilibrium condition by an air flow at atmospheric pressure. Effects of the air flow rates on the dynamics, ground-state OH distributions and spectral characterization of UV...

  13. Lung volume and expiratory flow rates from pre- to post-puberty.

    Science.gov (United States)

    Smith, Joshua R; Emerson, Sam R; Kurti, Stephanie P; Gandhi, Kirti; Harms, Craig A

    2015-08-01

    The purpose was to determine if the airways and lungs grow disproportionately from pre- to post-puberty in boys and girls. We hypothesized that the airways grow at a slower rate than lung volume (i.e. dysanapsis growth) during puberty and boys would exhibit more dysanaptic growth compared to girls. Twenty-one pre-pubescent children [11 boys (pre 10.1 ± 0.5 years, post 15.3 ± 0.5 years); 10 girls (pre 9.4 ± 1.0 years, post 14.1 ± 1.0 years)] performed pulmonary function tests (PFTs) ~5 years ago from an original cohort of 40 children. These 21 children performed PFTs, which included forced vital capacity (FVC) and forced expiratory flow at 50 % FVC (FEF50). Static pressure at 50 % of FVC [Pst(L)50 %] was estimated based on age. Dysanapsis ratio (DR) was calculated [FEF50 × FVC(-1) × Pst(L) 50 % (-1) ]. Maturation status was determined via Tanner stages. Stage of maturation was not different (p > 0.05) between boys and girls (4.2 ± 0.6 stage vs. 3.7 ± 0.7 stage, respectively). FVC and FEF50 increased (p 0.05) from pre- to post-puberty. FEF50 and FVC significantly increased and DR decreased (p puberty for both sexes. Post-puberty, boys had a significantly larger FVC, but FEF50, DR, and FEF50/FVC were not different (p > 0.05) compared to girls. These data suggest that dysanaptic growth occurs during puberty and that it is not different between boys and girls.

  14. Beta-decay rate and beta-delayed neutron emission probability of improved gross theory

    Science.gov (United States)

    Koura, Hiroyuki

    2014-09-01

    A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for unmeasured nuclei are adopted from the KTUY nuclear mass formula, which is based on the spherical-basis method. Considering the properties of the integrated Fermi function, we can roughly categorized energy region of excited-state of a daughter nucleus into three regions: a highly-excited energy region, which fully affect a delayed neutron probability, a middle energy region, which is estimated to contribute the decay heat, and a region neighboring the ground-state, which determines the beta-decay rate. Some results will be given in the presentation. A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for

  15. Why nuclear energy is essential to reduce anthropogenic greenhouse gas emission rates

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, A. [Univ. Politecnica de Madrid, Madrid (Spain); Brook, B.W. [Univ. of Tasmania, Hobart TAS (Australia); Meneley, D.A. [Candu Energy Inc., Mississauga, Ontario (Canada); Misak, J. [UJV-Rez, Prague (Czech Republic); Blees, T. [Science Council for Global Initiatives, Chicago, Illinois (United States); Van Erp, J.B. [Illinois Commission on Atomic Energy, Chicago, Illinois (United States)

    2015-12-15

    Reduction of anthropogenic greenhouse gas emissions is advocated by the Intergovernmental Panel on Climate Change. To achieve this target, countries have opted for renewable energy sources, primarily wind and solar. These renewables will be unable to supply the needed large quantities of energy to run industrial societies sustainably, economically and reliably because they are inherently intermittent, depending on flexible backup power or on energy storage for delivery of base-load quantities of electrical energy. The backup power is derived in most cases from combustion of natural gas. Intermittent energy sources, if used in this way, do not meet the requirements of sustainability, nor are they economically viable because they require redundant, under- utilized investment in capacity both for generation and for transmission. Because methane is a potent greenhouse gas, the equivalent carbon dioxide value of methane may cause gas-fired stations to emit more greenhouse gas than coal-fired plants of the same power for currently reported leakage rates of the natural gas. Likewise, intermittent wind/solar photovoltaic systems backed up by gas-fu:ed power plants also release substantial amounts of carbon-dioxide- equivalent greenhouse gas to make such a combination environmentally unacceptable. In the long term, nuclear fission technology is the only known energy source that is capable of delivering the needed large quantities of energy safely, economically, reliably and in a sustainable way, both environmentally and as regards the available resource-base. (author)

  16. Why nuclear energy is essential to reduce anthropogenic greenhouse gas emission rates

    International Nuclear Information System (INIS)

    Alonso, A.; Brook, B.W.; Meneley, D.A.; Misak, J.; Blees, T.; Van Erp, J.B.

    2015-01-01

    Reduction of anthropogenic greenhouse gas emissions is advocated by the Intergovernmental Panel on Climate Change. To achieve this target, countries have opted for renewable energy sources, primarily wind and solar. These renewables will be unable to supply the needed large quantities of energy to run industrial societies sustainably, economically and reliably because they are inherently intermittent, depending on flexible backup power or on energy storage for delivery of base-load quantities of electrical energy. The backup power is derived in most cases from combustion of natural gas. Intermittent energy sources, if used in this way, do not meet the requirements of sustainability, nor are they economically viable because they require redundant, under- utilized investment in capacity both for generation and for transmission. Because methane is a potent greenhouse gas, the equivalent carbon dioxide value of methane may cause gas-fired stations to emit more greenhouse gas than coal-fired plants of the same power for currently reported leakage rates of the natural gas. Likewise, intermittent wind/solar photovoltaic systems backed up by gas-fu:ed power plants also release substantial amounts of carbon-dioxide- equivalent greenhouse gas to make such a combination environmentally unacceptable. In the long term, nuclear fission technology is the only known energy source that is capable of delivering the needed large quantities of energy safely, economically, reliably and in a sustainable way, both environmentally and as regards the available resource-base. (author)

  17. Effect of different saline chaser volumes and flow rates on intravascular contrast enhancement in CT using a circulation phantom

    International Nuclear Information System (INIS)

    Behrendt, Florian F.; Bruners, Philipp; Keil, Sebastian; Plumhans, Cedric; Mahnken, Andreas H.; Das, Marco; Ackermann, Diana; Guenther, Rolf W.; Muehlenbruch, Georg

    2010-01-01

    Purpose: To evaluate the influence of different saline chaser volumes and different saline chaser flow rates on the intravascular contrast enhancement in MDCT. Materials and methods: In a physiological flow phantom contrast medium (120 ml, 300 mgI/ml, Ultravist 300) was administered at a flow rate of 6 ml/s followed by different saline chaser volumes (0, 30, 60 and 90 ml) at the same injection rate or followed by a 30-ml saline chaser at different injection rates (2, 4, 6 and 8 ml/s). Serial CT-scans at a level covering the pulmonary artery, the ascending and the descending aorta replica were obtained. Time-enhancement curves were computed and both pulmonary and aortic peak enhancement and peak time were determined. Results: Compared to contrast medium injection without a saline chaser the pushing with a saline chaser (30, 60, and 90 ml) resulted in a statistically significant increased pulmonary peak enhancement (all p = 0.008) and prolonged peak time (p = 0.032, p = 0.024 and p = 0.008, respectively). Highest aortic peak enhancement values were detected for a saline chaser volume of 30 ml. A saline chaser flow rate of 8 ml/s resulted in the highest pulmonary peak enhancement values compared to flow rates of 2, 4 and 6 ml/s (all p = 0.008). Aortic peak enhancement showed the highest values for a flow rate of 6 ml/s. Conclusion: A saline chaser volume of 30 ml and an injection rate of 6 ml/s are sufficient to best improve vascular contrast enhancement in the pulmonary artery and the aorta in MDCT.

  18. 75 FR 14479 - Reallocation of Unused Fiscal Year 2010 Tariff-Rate Quota Volume for Raw Cane Sugar

    Science.gov (United States)

    2010-03-25

    ...-Rate Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION... (TRQ) for imported raw cane sugar. DATES: Effective Date: March 25, 2010. ADDRESSES: Inquiries may be... (HTS), the United States maintains TRQs for imports of raw cane and refined sugar. Section 404(d)(3) of...

  19. The Effects of TM on Concurrent Heart Rate, Peripheral Blood Pulse Volume, and the Alpha Wave Frequency.

    Science.gov (United States)

    Lukas, Jerome S.

    Through observation of 26 subjects over a 3 month period, this research project measured the effects of transcendental meditation (TM) on concurrent heart rate, peripheral blood pulse volume, and the alpha wave frequency. The subjects were assigned randomly to three groups. One group practiced TM as prescribed by the International Meditation…

  20. Effect of C/N ratio, aeration rate and moisture content on ammonia and greenhouse gas emission during the composting.

    Science.gov (United States)

    Jiang, Tao; Schuchardt, Frank; Li, Guoxue; Guo, Rui; Zhao, Yuanqiu

    2011-01-01

    Gaseous emission (N2O, CH4 and NH3) from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N ratio, aeration rate and initial moisture content on gaseous emission during the composting of pig faeces from Chinese Ganqinfen system. The results showed that about 23.9% to 45.6% of total organic carbon (TOC) was lost in the form of CO2 and 0.8% to 7.5% of TOC emitted as CH4. Most of the nitrogen was lost in the form of NH3, which account for 9.6% to 32.4% of initial nitrogen. N2O was also an important way of nitrogen losses and 1.5% to 7.3% of initial total nitrogen was lost as it. Statistic analysis showed that the aeration rate is the most important factor which could affect the NH3 (p = 0.0189), CH4 (p = 0.0113) and N2O (p = 0.0493) emissions significantly. Higher aeration rates reduce the CH4 emission but increase the NH3 and N2O losses. C/N ratio could affect the NH3 (p = 0.0442) and CH4 (p = 0.0246) emissions significantly, but not the N2O. Lower C/N ratio caused higher NH3 and CH4 emissions. The initial moisture content can not influence the gaseous emission significantly. Most treatments were matured after 37 days, except a trial with high moisture content and a low C/N ratio.

  1. Dynamics, OH distributions and UV emission of a gliding arc at various flow-rates investigated by optical measurements

    International Nuclear Information System (INIS)

    Zhu, Jiajian; Sun, Zhiwei; Li, Zhongshan; Ehn, Andreas; Aldén, Marcus; Salewski, Mirko; Leipold, Frank; Kusano, Yukihiro

    2014-01-01

    We demonstrate a plasma discharge which is generated between two diverging electrodes and extended into a gliding arc in non-equilibrium condition by an air flow at atmospheric pressure. Effects of the air flow rates on the dynamics, ground-state OH distributions and spectral characterization of UV emission of the gliding arc were investigated by optical methods. High-speed photography was utilized to reveal flow-rate dependent dynamics such as ignitions, propagation, short-cutting events, extinctions and conversions of the discharge from glowtype to spark-type. Short-cutting events and ignitions occur more frequently at higher flow rates. The anchor points of the gliding arc are mostly steady at the top of the electrodes at lower flow rates whereas at higher flow rates they glide up along the electrodes most of the time. The afterglow of fully developed gliding arcs is observed to decay over hundreds of microseconds after being electronically short-cut by a newly ignited arc. The extinction time decreases with the increase of the flow rate. The frequency of the conversion of a discharge from glow-type to spark-type increases with the flow rate. Additionally, spatial distributions of ground-state OH were investigated using planar laser-induced fluorescence. The results show that the shape, height, intensity and thickness of ground-state OH distribution vary significantly with air flow rates. Finally, UV emission of the gliding arc is measured using optical emission spectroscopy and it is found that the emission intensity of NO γ (A-X), OH (A-X) and N 2 (C-B) increase with the flow rates showing more characteristics of spark-type arcs. The observed phenomena indicate the significance of the interaction between local turbulence and the gliding arc. (paper)

  2. Dynamics, OH distributions and UV emission of a gliding arc at various flow-rates investigated by optical measurements

    Science.gov (United States)

    Zhu, Jiajian; Sun, Zhiwei; Li, Zhongshan; Ehn, Andreas; Aldén, Marcus; Salewski, Mirko; Leipold, Frank; Kusano, Yukihiro

    2014-07-01

    We demonstrate a plasma discharge which is generated between two diverging electrodes and extended into a gliding arc in non-equilibrium condition by an air flow at atmospheric pressure. Effects of the air flow rates on the dynamics, ground-state OH distributions and spectral characterization of UV emission of the gliding arc were investigated by optical methods. High-speed photography was utilized to reveal flow-rate dependent dynamics such as ignitions, propagation, short-cutting events, extinctions and conversions of the discharge from glowtype to spark-type. Short-cutting events and ignitions occur more frequently at higher flow rates. The anchor points of the gliding arc are mostly steady at the top of the electrodes at lower flow rates whereas at higher flow rates they glide up along the electrodes most of the time. The afterglow of fully developed gliding arcs is observed to decay over hundreds of microseconds after being electronically short-cut by a newly ignited arc. The extinction time decreases with the increase of the flow rate. The frequency of the conversion of a discharge from glow-type to spark-type increases with the flow rate. Additionally, spatial distributions of ground-state OH were investigated using planar laser-induced fluorescence. The results show that the shape, height, intensity and thickness of ground-state OH distribution vary significantly with air flow rates. Finally, UV emission of the gliding arc is measured using optical emission spectroscopy and it is found that the emission intensity of NO γ (A-X), OH (A-X) and N2 (C-B) increase with the flow rates showing more characteristics of spark-type arcs. The observed phenomena indicate the significance of the interaction between local turbulence and the gliding arc.

  3. What could have caused pre-industrial biomass burning emissions to exceed current rates?

    NARCIS (Netherlands)

    van der Werf, G. R.; Peters, W.; van Leeuwen, T. T.; Giglio, L.

    2012-01-01

    Recent studies based on trace gas mixing ratios in ice cores and charcoal data indicate that biomass burning emissions over the past millennium exceeded contemporary emissions by up to a factor of 4 for certain time periods. This is surprising because various sources of biomass burning are linked

  4. Plant-specific volatile organic compound emission rates from young and mature leaves of Mediterranean vegetation

    Science.gov (United States)

    Bracho-Nunez, Araceli; Welter, Saskia; Staudt, Michael; Kesselmeier, Jürgen

    2011-08-01

    The seasonality of vegetation, i.e., developmental stages and phenological processes, affects the emission of volatile organic compounds (VOCs). Despite the potential significance, the contributions of seasonality to VOC emission quality and quantity are not well understood and are therefore often ignored in emission simulations. We investigated the VOC emission patterns of young and mature leaves of several Mediterranean plant species in relation to their physiological and developmental changes during the growing period and estimated Es. Foliar emissions of isoprenoids and oxygenated VOCs like methanol and acetone were measured online by means of a proton transfer reaction mass spectrometer (PTR-MS) and offline with gas chromatography coupled with a mass spectrometer and flame ionization detector. The results suggest that VOC emission is a developmentally regulated process and that quantitative and qualitative variability is plant species specific. Leaf ontogeny clearly influenced both the VOC Es and the relative importance of different VOCs. Methanol was the major compound contributing to the sum of target VOC emissions in young leaves (11.8 ± 10.4 μg g-1 h-1), while its contribution was minor in mature leaves (4.1 ± 4.1 μg g-1 h-1). Several plant species showed a decrease or complete subsidence of monoterpene, sesquiterpene, and acetone emissions upon maturity, perhaps indicating a potential response to the higher defense demands of young emerging leaves.

  5. Overflow system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  6. 1st stage mote system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts to characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was f...

  7. 2nd stage lint cleaning system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  8. 1st stage lint cleaning system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  9. Mote cleaner system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  10. Combined mote system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  11. Mote cyclone robber system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  12. Unloading system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  13. Mote trash system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  14. Combined lint cleaning system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  15. Cyclone robber system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  16. 2nd stage mote system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  17. Master trash system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  18. Effect of urease inhibitor application rate and rainfall on ammonia emissions from beef manure

    Science.gov (United States)

    Social, economic, and environmental factors have prompted the desire to reduce global atmospheric ammonia emissions. A research project was conducted to assess the efficacy of the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) for reducing ammonia emissions from simulated open-lot beef...

  19. Battery condenser system total particulate emission factors and rates for cotton gins: Method 17

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  20. Battery condenser system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that to characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study ...

  1. Battery condenser system total particulate emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  2. What could have caused pre-industrial biomass burning emissions to exceed current rates?

    NARCIS (Netherlands)

    Werf, van der G.R.; Peters, W.; Leeuwen, van T.T.; Giglio, L.

    2013-01-01

    Recent studies based on trace gas mixing ratios in ice cores and charcoal data indicate that biomass burning emissions over the past millennium exceeded contemporary emissions by up to a factor of 4 for certain time periods. This is surprising because various sources of biomass burning are linked

  3. Comparisons of MOVES Light-duty Gasoline NOx Emission Rates with Real-world Measurements

    Science.gov (United States)

    Choi, D.; Sonntag, D.; Warila, J.

    2017-12-01

    Recent studies have shown differences between air quality model estimates and monitored values for nitrogen oxides. Several studies have suggested that the discrepancy between monitored and modeled values is due to an overestimation of NOx from mobile sources in EPA's emission inventory, particularly for light-duty gasoline vehicles. EPA's MOtor Vehicle Emission Simulator (MOVES) is an emission modeling system that estimates emissions for cars, trucks and other mobile sources at the national, county, and project level for criteria pollutants, greenhouse gases, and air toxics. Studies that directly measure vehicle emissions provide useful data for evaluating MOVES when the measurement conditions are properly accounted for in modeling. In this presentation, we show comparisons of MOVES2014 to thousands of real-world NOx emissions measurements from individual light-duty gasoline vehicles. The comparison studies include in-use vehicle emissions tests conducted on chassis dynamometer tests in support of Denver, Colorado's Vehicle Inspection & Maintenance Program and remote sensing data collected using road-side instruments in multiple locations and calendar years in the United States. In addition, we conduct comparisons of MOVES predictions to fleet-wide emissions measured from tunnels. We also present details on the methodology used to conduct the MOVES model runs in comparing to the independent data.

  4. Factors affecting volume calculation with single photon emission tomography (SPECT) method

    International Nuclear Information System (INIS)

    Liu, T.H.; Lee, K.H.; Chen, D.C.P.; Ballard, S.; Siegel, M.E.

    1985-01-01

    Several factors may influence the calculation of absolute volumes (VL) from SPECT images. The effect of these factors must be established to optimize the technique. The authors investigated the following on the VL calculations: % of background (BG) subtraction, reconstruction filters, sample activity, angular sampling and edge detection methods. Transaxial images of a liver-trunk phantom filled with Tc-99m from 1 to 3 μCi/cc were obtained in 64x64 matrix with a Siemens Rota Camera and MDS computer. Different reconstruction filters including Hanning 20,32, 64 and Butterworth 20, 32 were used. Angular samplings were performed in 3 and 6 degree increments. ROI's were drawn manually and with an automatic edge detection program around the image after BG subtraction. VL's were calculated by multiplying the number of pixels within the ROI by the slice thickness and the x- and y- calibrations of each pixel. One or 2 pixel per slice thickness was applied in the calculation. An inverse correlation was found between the calculated VL and the % of BG subtraction (r=0.99 for 1,2,3 μCi/cc activity). Based on the authors' linear regression analysis, the correct liver VL was measured with about 53% BG subtraction. The reconstruction filters, slice thickness and angular sampling had only minor effects on the calculated phantom volumes. Detection of the ROI automatically by the computer was not as accurate as the manual method. The authors conclude that the % of BG subtraction appears to be the most important factor affecting the VL calculation. With good quality control and appropriate reconstruction factors, correct VL calculations can be achieved with SPECT

  5. Carbon emissions and sequestration in forests: Case studies from seven developing countries. Volume 2, Greenhouse gas emissions from deforestration in the Brazilian Amazon

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, W.; Sathaye, J. [eds.] [Lawrence Berkeley Lab., CA (United States); Fearnside, P.M. [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Departmento de Ecologia

    1992-08-01

    Deforestation in Brazilian Amazonia in 1990 was releasing approximately 281--282 X 10{sup 6} metric tons (MT) of carbon on conversion to a landscape of agriculture, productive pasture, degraded pasture, secondary forest and regenerated forest in the proportions corresponding to the equilibrium condition implied by current land-use patterns. Emissions are expressed as ``committed carbon,`` or the carbon released over a period of years as the carbon stock in each hectare deforested approaches a new equilibrium in the landscape that replaces the original forest. To the extent that deforestation rates have remained constant, current releases from the areas deforested in previous years will be equal to the future releases from the areas being cleared now. Considering the quantities of carbon dioxide, carbon monoxide, methane, nitrous oxide, NO{sub x} and non-methane hydrocarbons released raises the impact by 22--37%. The relative impact on the greenhouse effect of each gas is based on the Intergovernmental Panel on Climate Change (IPCC) calculations over a 20-year time period (including indirect effects). The six gases considered have a combined global warming impact equivalent to 343 to 386 million MT of C0{sub 2}-equivalent carbon, depending on assumptions regarding the release of methane and other gases from the various sources such as burning and termites. These emissions represent 7--8 times the 50 million MT annual carbon release from Brazil`s use of fossil fuels, but bring little benefit to the country. Stopping deforestation in Brazil would prevent as much greenhouse emission as tripling the fuel efficiency of all the automobiles in the world. The relatively cheap measures needed to contain deforestation, together with the many complementary benefits of doing so, make this the first priority for funds intended to slow global warming.

  6. Determination of the emission rate for the 14 MeV neutron generator with the use of radio-yttrium

    Directory of Open Access Journals (Sweden)

    Laszynska Ewa

    2015-06-01

    Full Text Available The neutron emission rate is a crucial parameter for most of the radiation sources that emit neutrons. In the case of large fusion devices the determination of this parameter is necessary for a proper assessment of the power release and the prediction for the neutron budget. The 14 MeV neutron generator will be used for calibration of neutron diagnostics at JET and ITER facilities. The stability of the neutron generator working parameters like emission and angular homogeneity affects the accuracy of calibration other neutron diagnostics. The aim of our experiment was to confirm the usefulness of yttrium activation method for monitoring of the neutron generator SODERN Model: GENIE 16. The reaction rate induced by neutrons inside the yttrium sample was indirectly measured by activation of the yttrium sample, and then by means of the γ-spectrometry method. The pre-calibrated HPGe detector was used to determine the yttrium radioactivity. The emissivity of neutron generator calculated on the basis of the measured radioactivity was compared with the value resulting from its electrical settings, and both of these values were found to be consistent. This allowed for a positive verification of the reaction cross section that was used to determine the reaction rate (6.45 × 10−21 reactions per second and the neutron emission rate (1.04 × 108 n·s−1. Our study confirms usefulness of the yttrium activation method for monitoring of the neutron generator.

  7. Effects of nitrogen fertilisation rate and maturity of grass silage on methane emission by lactating dairy cows

    NARCIS (Netherlands)

    Warner, D.; Hatew, B.; Podesta, S.C.; Klop, G.; Gastelen, van S.; Laar, van H.; Dijkstra, J.; Bannink, A.

    2016-01-01

    Grass silage is typically fed to dairy cows in temperate regions. However, in vivo information on methane (CH4) emission from grass silage of varying quality is limited. We evaluated the effect of two rates of nitrogen (N) fertilisation of grassland (low fertilisation (LF), 65 kg of N/ha; and high

  8. Measurement of the volume growth rate of single budding yeast with the MOSFET-based microfluidic Coulter counter.

    Science.gov (United States)

    Sun, Jiashu; Stowers, Chris C; Boczko, Erik M; Li, Deyu

    2010-11-07

    We report on measurements of the volume growth rate of ten individual budding yeast cells using a recently developed MOSFET-based microfluidic Coulter counter. The MOSFET-based microfluidic Coulter counter is very sensitive, provides signals that are immune from the baseline drift, and can work with cell culture media of complex composition. These desirable features allow us to directly measure the volume growth rate of single cells of Saccharomyces cerevisiae LYH3865 strain budding yeast in YNB culture media over a whole cell cycle. Results indicate that all budding yeast follow a sigmoid volume growth profile with reduced growth rates at the initial stage before the bud emerges and the final stage after the daughter gets mature. Analysis of the data indicates that even though all piecewise linear, Gomperitz, and Hill's function models can fit the global growth profile equally well, the data strongly support local exponential growth phenomenon. Accurate volume growth measurements are important for applications in systems biology where quantitative parameters are required for modeling and simulation.

  9. Integer, fractional, and anomalous quantum Hall effects explained with Eyring's rate process theory and free volume concept.

    Science.gov (United States)

    Hao, Tian

    2017-02-22

    The Hall effects, especially the integer, fractional and anomalous quantum Hall effects, have been addressed using Eyring's rate process theory and free volume concept. The basic assumptions are that the conduction process is a common rate controlled "reaction" process that can be described with Eyring's absolute rate process theory; the mobility of electrons should be dependent on the free volume available for conduction electrons. The obtained Hall conductivity is clearly quantized as with prefactors related to both the magnetic flux quantum number and the magnetic quantum number via the azimuthal quantum number, with and without an externally applied magnetic field. This article focuses on two dimensional (2D) systems, but the approaches developed in this article can be extended to 3D systems.

  10. High rates of denitrification and nitrous oxide emission in arid biological soil crusts from the Sultanate of Oman

    DEFF Research Database (Denmark)

    Abed, Raeid M M; Lam, Phyllis; De Beer, Dirk

    2013-01-01

    Using a combination of process rate determination, microsensor profiling and molecular techniques, we demonstrated that denitrification, and not anaerobic ammonium oxidation (anammox), is the major nitrogen loss process in biological soil crusts from Oman. Potential denitrification rates were 584...... that nitrogen loss via denitrification is a dominant process in crusts from Oman, which leads to N 2 O gas emission and potentially reduces desert soil fertility....

  11. THE Hα LUMINOSITY FUNCTION AND STAR FORMATION RATE VOLUME DENSITY AT z = 0.8 FROM THE NEWFIRM Hα SURVEY

    International Nuclear Information System (INIS)

    Ly Chun; Lee, Janice C.; Momcheva, Ivelina; Dale, Daniel A.; Staudaher, Shawn; Moore, Carolynn A.; Salim, Samir; Finn, Rose

    2011-01-01

    We present new measurements of the Hα luminosity function (LF) and star formation rate (SFR) volume density for galaxies at z ∼ 0.8. Our analysis is based on 1.18 μm narrowband data from the NEWFIRM Hα (NewHα) Survey, a comprehensive program designed to capture deep samples of intermediate redshift emission-line galaxies using narrowband imaging in the near-infrared. The combination of depth (∼1.9 x 10 -17 erg s -1 cm -2 in Hα at 3σ) and areal coverage (0.82 deg 2 ) of the 1.18 μm observations complements other recent Hα studies at similar redshifts, and enables us to minimize the impact of cosmic variance and place robust constraints on the shape of the LF. The present sample contains 818 NB118 excess objects, 394 of which are selected as Hα emitters. Optical spectroscopy has been obtained for 62% of the NB118 excess objects. Empirical optical broadband color classification is used to sort the remainder of the sample. A comparison of the LFs constructed for the four individual fields covered by the observations reveals significant cosmic variance, emphasizing that multiple, widely separated observations are required for such analyses. The dust-corrected LF is well described by a Schechter function with L * = 10 43.00±0.52 erg s -1 , Φ * = 10 -3.20±0.54 Mpc -3 , and α = -1.6 ± 0.19. We compare our Hα LF and SFR density to those at z ∼ 3.4 , which we attribute to significant L * evolution. Our Hα SFR density of 10 -1.00±0.18 M sun yr -1 Mpc -3 is consistent with UV and [O II] measurements at z ∼ 1. We discuss how these results compare to other Hα surveys at z ∼ 0.8, and find that the different methods used to determine survey completeness can lead to inconsistent results. This suggests that future surveys probing fainter luminosities are needed, and more rigorous methods of estimating the completeness should be adopted as standard procedure (for example, with simulations which try to simultaneously reproduce the observed Hα LF and

  12. Hunger and thirst numeric rating scales are not valid estimates for gastric content volumes: a prospective investigation in healthy children.

    Science.gov (United States)

    Buehrer, Sabin; Hanke, Ursula; Klaghofer, Richard; Fruehauf, Melanie; Weiss, Markus; Schmitz, Achim

    2014-03-01

    A rating scale for thirst and hunger was evaluated as a noninvasive, simple and commonly available tool to estimate preanesthetic gastric volume, a surrogate parameter for the risk of perioperative pulmonary aspiration, in healthy volunteer school age children. Numeric scales with scores from 0 to 10 combined with smileys to rate thirst and hunger were analyzed and compared with residual gastric volumes as measured by magnetic resonance imaging and fasting times in three settings: before and for 2 h after drinking clear fluid (group A, 7 ml/kg), before and for 4 vs 6 h after a light breakfast followed by clear fluid (7 ml/kg) after 2 vs 4 h (crossover, group B), and before and for 1 h after drinking clear fluid (crossover, group C, 7 vs 3 ml/kg). In 30 children aged 6.4-12.8 (median 9.8) years, participating on 1-5 (median two) study days, 496 sets of scores and gastric volumes were determined. Large inter- and intra-individual variations were seen at baseline and in response to fluid and food intake. Significant correlations were found between hunger and thirst ratings in all groups, with children generally being more hungry than thirsty. Correlations between scores and duration of fasting or gastric residual volumes were poor to moderate. Receiver operating characteristic (ROC) analysis revealed that thirst and hunger rating scales cannot predict gastric content. Hunger and thirst scores vary considerably inter- and intra-individually and cannot predict gastric volume, nor do they correlate with fasting times in school age children. © 2013 John Wiley & Sons Ltd.

  13. Nitrous oxide emissions and denitrification rates: A blueprint for smart management and remediation of agricultural landscapes.

    Science.gov (United States)

    Tomasek, A.; Hondzo, M.; Kozarek, J. L.

    2015-12-01

    resulting in the release of nitrous oxide, a greenhouse gas with 300 times the warming potential of carbon dioxide. The investigation of nitrous oxide emissions and correlation to denitrification rates will facilitate smart management and remediation efforts of agricultural landscapes.

  14. Wood products in the waste stream: Characterization and combustion emissions. Volume 1. Final report

    International Nuclear Information System (INIS)

    1992-11-01

    Waste wood is wood separated from the solid-waste stream and processed into a uniform-sized product that is reused for other purposes such as fuel. As an alternative to the combustion of fossil fuels, it has raised concerns that if it is 'contaminated' with paints, resins, preservatives, etc., unacceptable environmental impacts may be generated during combustion. Given the difficulty of separating contaminated materials from waste wood and the large energy potential existing in the resource, it is important to identify possible problems associated with contaminated waste wood combustion. The study describes research about technical, public policy, and regulatory issues that affect the processing and combustion of waste wood for fuel. The project's purpose was to provide environmental regulators, project developers, and others with data to make informed decisions on the use of waste wood materials as a combustion resource. Potential environmental problems and solutions were identified. A specific project result was the identification of combustion system operation parameters and air pollution control technologies that can minimize emissions of identified air and solid waste contaminants from combustion of wood waste

  15. Cortical volumes and atrophy rates in FTD-3 CHMP2B mutation carriers and related non-carriers

    DEFF Research Database (Denmark)

    Eskildsen, Simon F; Østergaard, Lasse R; Rodell, Anders B

    2008-01-01

    with a mean interval of 16 months and surface based cortical segmentation we measured cortical thickness and volume, and quantified atrophy rates. Cortical thickness and atrophy rates were averaged within major lobes and focal effects were determined by parametric statistical maps. The volumetric atrophy...... in the frontal and occipital lobes, and in the left temporal lobe. Results indicated that cortical thickness has a higher sensitivity for detecting small changes than whole-brain volumetric measures. Comparing mutation carriers with non-carriers revealed increased atrophy rates in mutation carriers bilaterally...

  16. Acoustic emission

    International Nuclear Information System (INIS)

    Nichols, R.W.

    1976-01-01

    The volume contains six papers which together provide an overall review of the inspection technique known as acoustic emission or stress wave emission. The titles are: a welder's introduction to acoustic emission technology; use of acoustic emission for detection of defects as they arise during fabrication; examples of laboratory application and assessment of acoustic emission in the United Kingdom; (Part I: acoustic emission behaviour of low alloy steels; Part II: fatigue crack assessment from proof testing and continuous monitoring); inspection of selected areas of engineering structures by acoustic emission; Japanese experience in laboratory and practical applications of acoustic emission to welded structures; and ASME acoustic emission code status. (U.K.)

  17. Spatial and temporal variation in domestic biofuel consumption rates and patterns in Zimbabwe: implications for atmospheric trace gas emission

    International Nuclear Information System (INIS)

    Ludwig, J.; Andreae, M.O.; Helas, G.; Marufu, L.; University of Utrecht; Lelieveld, J.

    1999-01-01

    An ecologically nationwide and all-year-round domestic biofuel consumption study was conducted in Zimbabwe from January 1996 to March 1997. The study aimed at (a) establishing the determinants and magnitudes of spatial and temporal variations in biofuel consumption rates, (b) estimating the overall mean national rural and urban consumption rates, and (c) estimating the contribution of domestic biomass burning in Zimbabwe to the emission of atmospheric trace gases. The main source of spatial variation in biofuel consumption rates was found to be settlement type (rural or urban). Within a settlement type, per capita consumption rates varied in time and space with household size, ambient temperature, and physical availability. In rural areas wood and agricultural residues were consumed at national average rates of 1.3±0.2 and 0.07±0.01 tonnes capita -1 year -1 , respectively. In urban centres wood was consumed at an average rate of 0.4±0.26 tonnes capita -1 year -1 . These consumption rates translate into emission outputs from Zimbabwe of 4.6 Tg CO 2 -C year -1 , 0.4 Tg CO-C year -1 , 5.3 Gg NO-N year -1 , 14.5 Gg CH 4 -C year -1 , 24.2 Gg NMHC-C year -1 , 2.9 Gg organic acid-C year -1 (formic and acetic acids) and 48.4 Gg aerosol-C year -1 . For CO 2 , CO, and NO, these domestic biofuel emissions represent 41±6%, 67±6%, and 8±1%, respectively, of the total output of all sources evaluated and documented in Zimbabwe to date. This means that of the studied sources, domestic biomass burning is the major source of CO 2 and CO emission in Zimbabwe

  18. A case study on the impact of variable emission rates on the calculated MEI

    Energy Technology Data Exchange (ETDEWEB)

    Perry, R.A.; Chadbourne, J.

    1994-12-31

    When regulatory agencies require dispersion modeling to evaluate air quality impacts, the emissions modeled are the maximum allowable emissions. This requires an assumption that the source will constantly emit the maximum amount of each contaminant allowed by rule or by permit condition. For most sources, the actual emissions are typically much lower than the maximum allowed. Some years ago the Agency considered this issue through the ExEx policy to provide for specified {open_quotes}expected exceedances{close_quotes} while still meeting ambient standards. Emissions of Resource Conservation and Recovery Act (RCRA) metals from a cement kiln, using hazardous waste to replace fossil fuels, provides a useful example of the effect of variable emissions. The Boiler and Industrial Furnace (BIF) rule at 40 C.F.R. 266 subpart H specifies that allowable emission of arsenic, beryllium, cadmium, chromium, lead and thallium inter alia can be determined through dispersion modeling. Section 266.103(b)(v) specifies that the location of the most exposed individual (MEI) and dilution faction ({mu}g/m{sup 3} / g/sec) for the maximum annual average value must be determined. In addition, risk specific doses and reference air concentration (RSDs and RACs in {mu}g/m{sup 3}) are published in BIF appendix IV and V based on 70 years of exposure.

  19. Steep Hard-X-ray Spectra Indicate Extremely High Accretion Rates in Weak Emission-Line Quasars

    Science.gov (United States)

    Marlar, Andrea; Shemmer, Ohad; Anderson, Scott F.; Brandt, W. Niel; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Luo, Bin; Plotkin, Richard; Richards, Gordon T.; Schneider, Donald P.; Wu, Jianfeng

    2018-06-01

    We present XMM-Newton imaging spectroscopy of ten weak emission-line quasars (WLQs) at 0.928 ≤ z ≤ 3.767, six of which are radio quiet and four which are radio intermediate. The new X-ray data enabled us to measure the hard-X-ray power-law photon index (Γ) in each source with relatively high accuracy. These measurements allowed us to confirm previous reports that WLQs have steeper X-ray spectra, therefore indicating higher accretion rates with respect to "typical" quasars. A comparison between the Γ values of our radio-quiet WLQs and those of a carefully-selected, uniform sample of 84 quasars shows that the first are significantly higher, at the ≥ 3σ level. Collectively, the four radio-intermediate WLQs have lower Γ values with respect to the six radio-quiet WLQs, as may be expected if the spectra of the first group are contaminated by X-ray emission from a jet. These results suggest that, in the absence of significant jet emission along our line of sight, WLQs constitute the extreme high end of the accretion rate distribution in quasars. We detect soft excess emission in our lowest-redshift radio-quiet WLQ, in agreement with previous findings suggesting that the prominence of this feature is associated with a high accretion rate. We have not detected signatures of Compton reflection, Fe Kα lines, or strong variability between two X-ray epochs in any of our WLQs.

  20. Comparison of five segmentation tools for 18F-fluoro-deoxy-glucose-positron emission tomography-based target volume definition in head and neck cancer.

    NARCIS (Netherlands)

    Schinagl, D.A.X.; Vogel, W.V.; Hoffmann, A.L.; Dalen, J.A. van; Oyen, W.J.G.; Kaanders, J.H.A.M.

    2007-01-01

    PURPOSE: Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with (18)F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may

  1. Load and resistance factor rating (LRFR) in New York State : volume II.

    Science.gov (United States)

    2011-09-01

    This report develops a Load and Resistance Factor Rating (NYS-LRFR) methodology : for New York bridges. The methodology is applicable for the rating of existing : bridges, the posting of under-strength bridges, and checking Permit trucks. The : propo...

  2. Load and resistance factor rating (LRFR) in New York State : volume I.

    Science.gov (United States)

    2011-09-01

    This report develops a Load and Resistance Factor Rating (NYS-LRFR) methodology : for New York bridges. The methodology is applicable for the rating of existing : bridges, the posting of under-strength bridges, and checking Permit trucks. The : propo...

  3. Measuring Star-Formation Rates of AGNs and QSOs using a new calibration from Polycyclic Aromatic Hydrocarbon Emission

    Science.gov (United States)

    Papovich, Casey

    Understanding the coevolution of star-formation and supermassive black hole accretion is one of the key questions in galaxy formation theory. This relation is important for understanding why at present the mass in galaxy bulges (on scales of kpc) correlates so tightly with the mass of galaxy central supermassive blackholes (on scales of AU). Feedback from supermassive black hole accretion may also be responsible for heating or expelling cold gas from galaxies, shutting off the fuel for star-formation and additional black hole growth. Did bulges proceed the formation of black holes, or vice versa, or are they contemporaneous? Therefore, understanding the exact rates of star-formation and supermassive black hole growth, and how they evolve with time and galaxy mass has deep implications for how galaxies form. It has previously been nearly impossible to study simultaneously both star-formation and accretion onto supermassive black holes in galaxies because the emission from black hole accretion contaminates nearly all diagnostics of star-formation. The "standard" diagnostics for the star-formation rate (the emission from hydrogen, UV emission, midIR emission, far-IR emission, etc) are not suitable for measuring star-formation rates in galaxies with actively accreting supermassive blackholes. In this proposal, the researchers request NASA/ADP funding for an archival study using spectroscopy with the Spitzer Space Telescope to measure simultaneously the star-formation rate (SFR) and bolometric emission from accreting supermassive blackholes to understand the complex relation between both processes. The key to this study is that they will develop a new calibrator for SFRs in galaxies with active supermassive black holes based on the molecular emission from polycyclic aromatic hydrocarbons (PAHs), which emit strongly in the mid-IR (3 - 20 micron) and are very strong in spectra from the Spitzer Space Telescope. The PAH molecules exist near photo-dissociation regions, and

  4. Potential of aeration flow rate and bio-char addition to reduce greenhouse gas and ammonia emissions during manure composting

    DEFF Research Database (Denmark)

    Chowdhury, Md Albarune; de Neergaard, Andreas; Jensen, Lars Stoumann

    2014-01-01

    -char on GHG and NH3 emissions from composting cattle slurry and hen manure in small-scale laboratory composters. Depending on treatment, cumulative C losses via CO2 and CH4 emissions accounted for 11.4-22.5% and 0.004-0.2% of initial total carbon, while N losses as N2O and NH3 emissions comprised 0.......05-0.1% and 0.8-26.5% of initial total nitrogen, respectively. Decreasing the flow rate reduced cumulative NH3 losses non-significantly (by 88%) but significantly increased CH4 losses (by 51%) from composting of cattle slurry with barley straw. Among the hen manure treatments evaluated, bio-char addition...

  5. An estimation of vehicle kilometer traveled and on-road emissions using the traffic volume and travel speed on road links in Incheon City.

    Science.gov (United States)

    Jung, Sungwoon; Kim, Jounghwa; Kim, Jeongsoo; Hong, Dahee; Park, Dongjoo

    2017-04-01

    The objective of this study is to estimate the vehicle kilometer traveled (VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors, large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea. Copyright © 2016. Published by Elsevier B.V.

  6. Emission Rate of Particulate Matter and Its Removal Efficiency by Precipitators in Under-Fired Charbroiling Restaurants

    Directory of Open Access Journals (Sweden)

    Jun-Bok Lee

    2011-01-01

    Full Text Available In order to explore the potent role of meat cooking processes as the emission sources of particulate matter (PM, emission rates and the associated removal efficiency by precipitators were estimated based on the on-site measurements made at five under-fired charbroiling (UFC restaurants. The emission patterns of PM for these five restaurants were compared after having been sorted into the main meat types used for cooking: beef (B, chicken (C, intestines (I, and pork (P: two sites. The mass concentrations (μg m-3 of three PM fractions (PM2.5/PM10/TSP measured from these restaurants were 15,510/15,701/17,175 (C; 8,525/10,760/12,676 (B; 11,027/13,249/13,488 (P; and 22,409/22,412/22,414 (I. Emission factors (g kg-1 for those PM fractions were also estimated as 3.23/4.08/4.80 (B, 3.07/3.82/3.87 (P, 8.12/8.22/8.99 (C, and 6.59/6.59/6.59 (I. If the annual emission rate of PM10 is extrapolated by combining its emission factor, population, activity factor, etc., it is estimated as 500 ton year-1, which corresponds to 2.4% of the PM10 budget in Seoul, Korea. Removal efficiencies of PM10 via precipitators, such as an electrostatic precipitator (ESP, bag filter (BF, and the combination system (ESP + catalyst, installed in those UFC restaurants ranged between 54.76 and 98.98%. The removal efficiency of PM by this control system was the least effective for particles with <0.4 μm, although those in the range of 0.4–10 μm were the most effective.

  7. Evaluation of economic and technical efficiency of diesel engines operation on the basis of volume combustion rate

    Directory of Open Access Journals (Sweden)

    І. О. Берестовой

    2016-11-01

    Full Text Available The article deals with a new approach to evaluation of complex efficiency of diesel engines. Traditionally, cylinder’s capacity, rotation frequency, average efficient pressure inside cylinder, piston’s stroke, average piston’s velocity, fuel specific consumption and other indices are used as generalizing criteria, characterizing diesel engine’s efficiency, but they do not reflect interrelation between engine’s complex efficiency and a set of economic, mass-dimensional, operational and ecological efficiency. The approach applied in the article makes it possible to reveal the existing and modify the existing methods of solving the problem of improving diesel engine’s efficiency with due regard to interrelation of the parameters, characterizing efficiency of their operation. Statistic analyses were carried out, on the basis of which an assumption regarding the existence of interrelation between specific fuel consumption and the analyzed engine’s parameters was made. Processing of statistical data for various analyzed functions of diesel engines helped offer a function, illustrating the link between volume combustion rate, piston’s area and nominal theoretical specific fuel consumption. Interrelation between volume combustion rate, nominal parameters of diesel operation and efficiency indices, obtained by processing statistical data of more than 500 models of diesels of different series was evaluated, the main feature of it being a mathematical trend. The analysis of the obtained function makes it possible to establish an interrelation between economic efficiency of a diesel, its main index being specific fuel consumption and volume combustion rate and design peculiarities

  8. Emissions of sulfur gases from marine and freshwater wetlands of the Florida Everglades: Rates and extrapolation using remote sensing

    Science.gov (United States)

    Hines, Mark E.; Pelletier, Ramona E.; Crill, Patrick M.

    1992-01-01

    Rates of emissions of the biogenic sulfur (S) gases carbonyl sulfide (COS), methyl mercaptan (MSH), dimethyl sulfide (DMS), and carbon disulfide (CS2) were measured in a variety of marine and freshwater wetland habitats in the Florida Everglades during a short duration period in October using dynamic chambers, cryotrapping techniques, and gas chromatography. The most rapid emissions of greater than 500 nmol/m(sup -2)h(sup -1) occurred in red mangrove-dominated sites that were adjacent to open seawater and contained numerous crab burrows. Poorly drained red mangrove sites exhibited lower fluxes of approximately 60 nmol/m(sup -2)h(sup -1) which were similar to fluxes from the black mangrove areas which dominated the marine-influenced wetland sites in the Everglades. DMS was the dominant organo-S gas emitted especially in the freshwater areas. Spectral data from a scene from the Landsat thematic mapper were used to map habitats in the Everglades. Six vegetation categories were delineated using geographical information system software and S gas emission were extrapolated for the entire Everglades National Park. The black mangrove-dominated areas accounted for the largest portion of S gas emissions to the area. The large area extent of the saw grass communities (42 percent) accounted for approximately 24 percent of the total S emissions.

  9. Effects of mix ratio, moisture content and aeration rate on sulfur odor emissions during pig manure composting.

    Science.gov (United States)

    Zang, Bing; Li, Shuyan; Michel, Frederick; Li, Guoxue; Luo, Yuan; Zhang, Difang; Li, Yangyang

    2016-10-01

    Sulfur compounds in swine manure can cause odor emissions during composting if conditions are not conducive to their rapid oxidation and degradation. In this study, the effects of controllable composting process variables on sulfur odor emissions were investigated. These included pig manure to corn stalk mix ratio (0.7:1, 1.5:1 and 2.2:1dw basis), initial moisture content (60%, 65%, 70% and 75%) and aeration rate (1.0, 2.0, 3.0 and 4.0m(3)m(-3)h(-1)). The compounds measured were carbonyl sulfide, carbon disulfide, hydrogen sulfide, methyl mercaptan, ethyl mercaptan, diethyl sulfide, dimethyl sulfide (Me2S) and dimethyl disulfide (Me2SS). The results showed that total sulfur losses ranged from 3.9% to 18.3% after 26days of composting. Me2S and Me2SS were the primary (>59.61%) sulfur compounds released during this period. After turning, emission rates of both Me2S and Me2SS increased. Emissions of the other six sulfur compounds were low and inconsistent during composting. Within the compost, feedstock mix ratio significantly influenced the concentration of Me2SS, while aeration rate significantly affected Me2S concentration (pMoisture content did not have a significant effect on the concentrations of either of these two compounds. Concentrations of sulfur odor compounds were the lowest at the highest aeration rate. Therefore, high aeration rates during the thermophilic phase, especially after turning, are recommended to minimize sulfur odors produced during swine manure composting. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Application of a sawtooth surface to accelerator beam chambers with low electron emission rate

    International Nuclear Information System (INIS)

    Suetsugu, Y.; Tsuchiya, M.; Nishidono, T.; Kato, N.; Satoh, N.; Endo, S.; Yokoyama, T.

    2003-01-01

    One of the latest problems in positron or proton accelerators is a single-beam instability due to an electron cloud around the beam. The instability, for an example, causes a beam size blow up of the positron beam and deteriorates the performance of the electron-positron collider. the seed of the electron cloud is the electrons emitted from the surface of the beam chamber, which consists of electrons due to the synchrotron radiation (photoelectrons) and sometimes those multiplied by the multipactoring. Suppressing the electron emission from the surface is, therefore, an essential way to cure the instability. Here a rough surface with a sawtooth structure (sawtooth surface) is proposed to reduce the electron emission from the surface of the beam chamber. A new rolling-tap method is developed for this study to make the sawtooth surface in a circular beam chamber with a length of several meters. The first experiment using a test chamber at a photon beam line of the KEK Photon Factory verifies its validity. The photoelectron emission from the sawtooth surface reduces by one order of magnitude compared to the usual smooth surface. In the second experiment under a bunched positron beam in the KEK B-Factory, however, the electron emission is comparable to that of a smooth surface and the behavior is quite different from the previous one. The reason is that the beam field excites the multipactoring of electrons and the decrease of the photoelectron emission by the sawtooth surface is wiped out. The sawtooth surface will be effective to reduce the electron emission under the situation with external magnetic fields or without strong beam fields where the electron multipactoring hardly occurs

  11. Fugitive emission rates assessment of PM2.5 and PM10 from open storage piles in China

    Science.gov (United States)

    Cao, Yiqi; Liu, Tao; He, Jiao

    2018-03-01

    An assessment of the fugitive emission rates of PM2.5 and PM10 from an open static coal and mine storage piles. The experiment was conducted at a large union steel enterprises in the East China region to effectively control the fugitive particulate emissions pollution on daily work and extreme weather conditions. Wind tunnel experiments conducted on the surface of static storage piles, and it generated specific fugitive emission rates (SERs) at ground level of between ca.10-1 and ca.102 (mg/m2·s) for PM2.5 and between ca.101 and ca.103 (mg/m2·s) for PM10 under the u*(wind velocity) between ca.3.0 (m/s) and 10.0 (m/s). Research results show that SERs of different materials differ a lot. Material particulate that has lower surface moisture content generate higher SER and coal material generate higher SER than mine material. For material storage piles with good water infiltrating properties, aspersion is a very effective measure for control fugitive particulate emission.

  12. A comparison between the order and the volume fill rates for a base-stock inventory control system under a compound renewal demand process

    DEFF Research Database (Denmark)

    Larsen, Christian; Thorstenson, Anders

    The order fill rate is less commonly used than the volume fill rate (most often just denoted fill rate) as a performance measure for inventory control systems. However, in settings where the focus is on filling customer orders rather than total quantities, the order fill rate should be the prefer......The order fill rate is less commonly used than the volume fill rate (most often just denoted fill rate) as a performance measure for inventory control systems. However, in settings where the focus is on filling customer orders rather than total quantities, the order fill rate should...

  13. Monte Carlo calculation of correction factors for radionuclide neutron source emission rate measurement by manganese bath method

    International Nuclear Information System (INIS)

    Li Chunjuan; Liu Yi'na; Zhang Weihua; Wang Zhiqiang

    2014-01-01

    The manganese bath method for measuring the neutron emission rate of radionuclide sources requires corrections to be made for emitted neutrons which are not captured by manganese nuclei. The Monte Carlo particle transport code MCNP was used to simulate the manganese bath system of the standards for the measurement of neutron source intensity. The correction factors were calculated and the reliability of the model was demonstrated through the key comparison for the radionuclide neutron source emission rate measurements organized by BIPM. The uncertainties in the calculated values were evaluated by considering the sensitivities to the solution density, the density of the radioactive material, the positioning of the source, the radius of the bath, and the interaction cross-sections. A new method for the evaluation of the uncertainties in Monte Carlo calculation was given. (authors)

  14. Volatile organic compounds from vegetation in southern Yunnan Province, China: Emission rates and some potential regional implications

    Science.gov (United States)

    Geron, Chris; Owen, Sue; Guenther, Alex; Greenberg, Jim; Rasmussen, Rei; Hui Bai, Jian; Li, Qing-Jun; Baker, Brad

    Little information is currently available regarding emissions of biogenic volatile organic compounds (BVOCs) in southern Asia. To address the need for BVOC emission estimates in regional atmospheric chemistry simulations, 95 common plant species were screened for emissions of BVOC in and near the Xishuangbanna Tropical Biological Gardens in southern Yunnan Province, Peoples' Republic of China in February 2003. In situ measurements with leaf cuvettes and branch bag enclosures were used in combination with portable gas chromatography, flame ionization, photoionization, and mass spectral detection to identify and quantify BVOC emissions. Forty-four of the species examined emitted isoprene at rates exceeding 20 μg C g -1 (leaf dry weight) h -1. An emphasis was placed on the genus Ficus, which is important in the region and occupies a wide range of ecological niches. Several species in the footprint of a nearby flux tower were also examined. Several palm species and an abundant fern ( Cyclosorus parasiticus) emitted substantial amounts of isoprene, and probably accounted for observed daytime mean isoprene fluxes from the understory of a Hevea brasiliensis plantation of 1.0 and 0.15 mg C m -2 h -1 during the wet and dry seasons, respectively. These measurements verify that both the forest floor and canopy in this region can be sources of isoprene. Monoterpene emissions exceeded 1.0 μg-C g -1 (leaf dry weight) h -1 from only 4 of 38 species surveyed, including some Ficus species and H. brasiliensis. However most of the trees of the latter species were sparsely foliated due to dry season senescence, and emission factors are approximately an order of magnitude lower than those reported during the wet season. BVOC emission rates and physiology of many species are impacted by reduced moisture availability, especially Mangifera indica. South Asia is a region undergoing rapid landuse change and forest plantation establishment, with large increases in area of high BVOC

  15. Battery condenser system PM2.5 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that detail a project to characterize cotton gin emissions from the standpoint of stack and ambient sampling. The impetus behind the project was the 2006 EPA implementation of a more stringent standard for particulate matter less than or equal to 2....

  16. Measurement of Ozone Emission and Particle Removal Rates from Portable Air Purifiers

    Science.gov (United States)

    Mang, Stephen A.; Walser, Maggie L.; Nizkorodov, Sergey A.; Laux, John M.

    2009-01-01

    Portable air purifiers are popular consumer items, especially in areas with poor air quality. Unfortunately, most users of these air purifiers have minimal understanding of the factors affecting their efficiency in typical indoor settings. Emission of the air pollutant ozone (O[subscript 3]) by certain air purifiers is of particular concern. In an…

  17. The absorption effect of the Lα-line Supplement to the paper 'On the Correlation Between the Hα-line emission rate and the ablation rate of a hydrogen pellet in tokamak discharges' – Nuclear Fusion 24 (1984) 697

    DEFF Research Database (Denmark)

    Chang, C. T.; Thomsen, Kenneth

    1985-01-01

    Several assumptions made in a previous study of the correlation between the Hα-line emission rate and the ablation rate of a hydrogen pellet injected into a tokamak discharge showed that the emission layer of the ablatant as optically thin with respect to all levels of the principal quantum numbe...

  18. Gaseous elemental mercury emissions and CO2 respiration rates in terrestrial soils under controlled aerobic and anaerobic laboratory conditions

    International Nuclear Information System (INIS)

    Obrist, Daniel; Fain, Xavier; Berger, Carsen

    2010-01-01

    Mercury (Hg) levels in terrestrial soils are linked to the presence of organic carbon (C). Carbon pools are highly dynamic and subject to mineralization processes, but little is known about the fate of Hg during decomposition. This study evaluated relationships between gaseous Hg emissions from soils and carbon dioxide (CO 2 ) respiration under controlled laboratory conditions to assess potential losses of Hg to the atmosphere during C mineralization. Results showed a linear correlation (r 2 = 0.49) between Hg and CO 2 emissions in 41 soil samples, an effect unlikely to be caused by temperature, radiation, different Hg contents, or soil moisture. Stoichiometric comparisons of Hg/C ratios of emissions and underlying soil substrates suggest that 3% of soil Hg was subject to evasion. Even minute emissions of Hg upon mineralization, however, may be important on a global scale given the large Hg pools sequestered in terrestrial soils and C stocks. We induced changes in CO 2 respiration rates and observed Hg flux responses, including inducement of anaerobic conditions by changing chamber air supply from N 2 /O 2 (80% and 20%, respectively) to pure N 2 . Unexpectedly, Hg emissions almost quadrupled after O 2 deprivation while oxidative mineralization (i.e., CO 2 emissions) was greatly reduced. This Hg flux response to anaerobic conditions was lacking when repeated with sterilized soils, possibly due to involvement of microbial reduction of Hg 2+ by anaerobes or indirect abiotic effects such as alterations in soil redox conditions. This study provides experimental evidence that Hg volatilization, and possibly Hg 2+ reduction, is related to O 2 availability in soils from two Sierra Nevada forests. If this result is confirmed in soils from other areas, the implication is that Hg volatilization from terrestrial soils is partially controlled by soil aeration and that low soil O 2 levels and possibly low soil redox potentials lead to increased Hg volatilization from soils.

  19. Low volume tubes are not effective to reduce the rate of hemolyzed specimens from the emergency department.

    Science.gov (United States)

    Lippi, Giuseppe; Bonelli, Patrizia; Graiani, Virna; Caleffi, Catia; Cervellin, Gianfranco

    2014-02-01

    Spurious hemolysis is the leading source of nonconformities that can be recorded in diagnostic samples, especially those collected in the emergency department (ED). The aim of this study was to assess whether the shift from regular to low volume blood collection tubes may reduce the rate of hemolysis in a large urban ED, where approximately 80% of blood collections are performed through catheters. In a former 5-month period, blood collection in the ED was performed using 5.0mL (13×100mm) plastic serum tubes, which were then completely replaced with 3.5mL (13×75mm) plastic serum tubes for another period of 5months. The rate of hemolyzed specimens (i.e., those containing a cell-free hemoglobin ≥0.5gL) collected in the two periods was compared by Fisher exact test. The rate of hemolyzed specimens received from the ED increased from 3.5% using 5.0mL plastic serum tubes to 5.2% after introduction of 3.5mL plastic serum tubes (p<0.001). The use of low volume tubes was not effective to decrease the hemolysis rate in a large urban ED. Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  20. Areal-averaged trace gas emission rates from long-range open-path measurements in stable boundary layer conditions

    Directory of Open Access Journals (Sweden)

    K. Schäfer

    2012-07-01

    Full Text Available Measurements of land-surface emission rates of greenhouse and other gases at large spatial scales (10 000 m2 are needed to assess the spatial distribution of emissions. This can be readily done using spatial-integrating micro-meteorological methods like flux-gradient methods which were evaluated for determining land-surface emission rates of trace gases under stable boundary layers. Non-intrusive path-integrating measurements are utilized. Successful application of a flux-gradient method requires confidence in the gradients of trace gas concentration and wind, and in the applicability of boundary-layer turbulence theory; consequently the procedures to qualify measurements that can be used to determine the flux is critical. While there is relatively high confidence in flux measurements made under unstable atmospheres with mean winds greater than 1 m s−1, there is greater uncertainty in flux measurements made under free convective or stable conditions. The study of N2O emissions of flat grassland and NH3 emissions from a cattle lagoon involves quality-assured determinations of fluxes under low wind, stable or night-time atmospheric conditions when the continuous "steady-state" turbulence of the surface boundary layer breaks down and the layer has intermittent turbulence. Results indicate that following the Monin-Obukhov similarity theory (MOST flux-gradient methods that assume a log-linear profile of the wind speed and concentration gradient incorrectly determine vertical profiles and thus flux in the stable boundary layer. An alternative approach is considered on the basis of turbulent diffusivity, i.e. the measured friction velocity as well as height gradients of horizontal wind speeds and concentrations without MOST correction for stability. It is shown that this is the most accurate of the flux-gradient methods under stable conditions.

  1. Simultaneous and multi-point measurement of ammonia emanating from human skin surface for the estimation of whole body dermal emission rate.

    Science.gov (United States)

    Furukawa, Shota; Sekine, Yoshika; Kimura, Keita; Umezawa, Kazuo; Asai, Satomi; Miyachi, Hayato

    2017-05-15

    Ammonia is one of the members of odor gases and a possible source of odor in indoor environment. However, little has been known on the actual emission rate of ammonia from the human skin surface. Then, this study aimed to estimate the whole-body dermal emission rate of ammonia by simultaneous and multi-point measurement of emission fluxes of ammonia employing a passive flux sampler - ion chromatography system. Firstly, the emission fluxes of ammonia were non-invasively measured for ten volunteers at 13 sampling positions set in 13 anatomical regions classified by Kurazumi et al. The measured emission fluxes were then converted to partial emission rates using the surface body areas estimated by weights and heights of volunteers and partial rates of 13 body regions. Subsequent summation of the partial emission rates provided the whole body dermal emission rate of ammonia. The results ranged from 2.9 to 12mgh -1 with an average of 5.9±3.2mgh -1 per person for the ten healthy young volunteers. The values were much greater than those from human breath, and thus the dermal emission of ammonia was found more significant odor source than the breath exhalation in indoor environment. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Airborne release fractions/rates and respirable fractions for nonreactor nuclear facilities. Volume 2, Appendices

    International Nuclear Information System (INIS)

    1994-12-01

    This document contains compiled data from the DOE Handbook on Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear facilities. Source data and example facilities utilized, such as the Plutonium Recovery Facility, are included

  3. arXiv Gravitational wave energy emission and detection rates of Primordial Black Hole hyperbolic encounters

    CERN Document Server

    García-Bellido, Juan

    2018-01-01

    We describe in detail gravitational wave bursts from Primordial Black Hole (PBH) hyperbolic encounters. The bursts are one-time events, with the bulk of the released energy happening during the closest approach, which can be emitted in frequencies that could be within the range of both LIGO (10-1000Hz) and LISA ($10^{-6}-1$ Hz). Furthermore, we correct the results for the power spectrum of hyperbolic encounters found in the literature and present new exact and approximate expressions for the peak frequency of the emission. Note that these GW bursts from hyperbolic encounters between PBH are complementary to the GW emission from the bounded orbits of BHB mergers detected by LIGO, and help breaking degeneracies in the determination of the PBH mass, spin and spatial distributions.

  4. A NEW LOOK AT THE TRADE VOLUME EFFECTS OF REAL EXCHANGE RATE RISK

    OpenAIRE

    Wang, Kai-Li; Barrett, Christopher B.

    2002-01-01

    This paper takes a new empirical look at the longstanding question of the effect of exchange rate volatility on international trade flows by studying the case of Taiwan's exports to the United States from 1989-1998. In particular, we employ sectoral level, monthly data and a multivariate GARCH-M estimator with corrections for leptokurtic errors that is consistent with the core hypothesis that traders' forward contracting behavior might be affected by exchange rate risk. We find that real exch...

  5. Multivariate analyses to assess the effects of surgeon and hospital volume on cancer survival rates: a nationwide population-based study in Taiwan.

    Directory of Open Access Journals (Sweden)

    Chun-Ming Chang

    Full Text Available BACKGROUND: Positive results between caseloads and outcomes have been validated in several procedures and cancer treatments. However, there is limited information available on the combined effects of surgeon and hospital caseloads. We used nationwide population-based data to explore the association between surgeon and hospital caseloads and survival rates for major cancers. METHODOLOGY: A total of 11,677 patients with incident cancer diagnosed in 2002 were identified from the Taiwan National Health Insurance Research Database. Survival analysis, the Cox proportional hazards model, and propensity scores were used to assess the relationship between 5-year survival rates and different caseload combinations. RESULTS: Based on the Cox proportional hazard model, cancer patients treated by low-volume surgeons in low-volume hospitals had poorer survival rates, and hazard ratios ranged from 1.3 in head and neck cancer to 1.8 in lung cancer after adjusting for patients' demographic variables, co-morbidities, and treatment modality. When analyzed using the propensity scores, the adjusted 5-year survival rates were poorer for patients treated by low-volume surgeons in low-volume hospitals, compared to those treated by high-volume surgeons in high-volume hospitals (P<0.005. CONCLUSIONS: After adjusting for differences in the case mix, cancer patients treated by low-volume surgeons in low-volume hospitals had poorer 5-year survival rates. Payers may implement quality care improvement in low-volume surgeons.

  6. County-Level Climate Uncertainty for Risk Assessments: Volume 26 Appendix Y - Historical Ridging Rate.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lowry, Thomas Stephen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Shannon M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Barry L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Malczynski, Leonard A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

  7. County-Level Climate Uncertainty for Risk Assessments: Volume 27 Appendix Z - Forecast Ridging Rate.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A.; Lowry, Thomas Stephen; Jones, Shannon M; Walker, La Tonya Nicole; Roberts, Barry L; Malczynski, Leonard A.

    2017-06-01

    This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

  8. Cerebral metabolic rates for glucose in mood disorders. Studies with positron emission tomography and fluorodeoxyglucose F 18

    International Nuclear Information System (INIS)

    Baxter, L.R. Jr.; Phelps, M.E.; Mazziotta, J.C.; Schwartz, J.M.; Gerner, R.H.; Selin, C.E.; Sumida, R.M.

    1985-01-01

    Cerebral metabolic rates for glucose were examined in patients with unipolar depression (N = 11), bipolar depression (N = 5), mania (N = 5), bipolar mixed states (N = 3), and in normal controls (N = 9) using positron emission tomography and fluorodeoxyglucose F 18. All subjects were studied supine under ambient room conditions with eyes open. Bipolar depressed and mixed patients had supratentorial whole brain glucose metabolic rates that were significantly lower than those of the other comparison groups. The whole brain metabolic rates for patients with bipolar depression increased going from depression or a mixed state to a euthymic or manic state. Patients with unipolar depression showed a significantly lower ratio of the metabolic rate of the caudate nucleus, divided by that of the hemisphere as a whole, when compared with normal controls and patients with bipolar depression

  9. Effect of Alfvén waves on the growth rate of the electron-cyclotron maser emission

    Energy Technology Data Exchange (ETDEWEB)

    Wu, D. J., E-mail: djwu@pmo.ac.cn [Purple Mountain Observatory, CAS, Nanjing 210008 (China)

    2014-06-15

    By using the non-relativistic approximation for the calculation of growth rates, but taking account of the weakly relativistic modification for the electron-cyclotron resonance condition, it is shown that the effect of Alfvén waves (AWs) on the electron-cyclotron maser emission leads to the significant increase of the O-mode growth rate, but has little effect on the X-mode growth rate. We propose that this is because the O-mode wave has the field-aligned polarization sense in the same as the field-aligned oscillatory current, which is created by the field-aligned oscillatory motion of the energetic electrons caused via the presence of AWs. It is this field-aligned oscillatory current that contributes a novel growth rate to the O-mode wave but has little effect on the X-mode wave.

  10. Evaluating the use of electrical resistivity imaging technique for improving CH4 and CO2 emission rate estimations in landfills

    International Nuclear Information System (INIS)

    Georgaki, I.; Soupios, P.; Sakkas, N.; Ververidis, F.; Trantas, E.; Vallianatos, F.; Manios, T.

    2008-01-01

    In order to improve the estimation of surface gas emissions in landfill, we evaluated a combination of geophysical and greenhouse gas measurement methodologies. Based on fifteen 2D electrical resistivity tomographies (ERTs), longitudinal cross section images of the buried waste layers were developed, identifying place and cross section size of organic waste (OW), organic waste saturated in leachates (SOW), low organic and non-organic waste. CH 4 and CO 2 emission measurements were then conducted using the static chamber technique at 5 surface points along two tomographies: (a) across a high-emitting area, ERT no. 2, where different amounts of relatively fresh OW and SOW were detected, and (b) across the oldest (at least eight years) cell in the landfill, ERT no. 6, with significant amounts of OW. Where the highest emission rates were recorded, they were strongly affected by the thickness of the OW and SOW fraction underneath each gas sampling point. The main reason for lower than expected values was the age of the layered buried waste. Lower than predicted emissions were also attributed to soil condition, which was the case at sampling points with surface ponding, i.e. surface accumulation of leachate (or precipitated water)

  11. Rate Proposal for Remuneration of Air Pollutants Emissions From Stationary Sources Located in Bogota D.C.

    Directory of Open Access Journals (Sweden)

    Gabriel Herrera Torres

    2011-04-01

    Full Text Available The objective of this project is to develop a methodological proposal for the establishment of the retributive rate for the direct use of the atmosphere as the receptor of pollutant emissions that come from stationary resources on Bogotá D.C. By means of the emissions from stationary sources inventory and the air quality analysis, the pollutant that are emitted by the industries and the ones that are regulated by the network observations of the were identified selecting the particulated matter (PM10, sulfur oxides (SOx, and nitrogen oxides (NOx as the atmospheric pollutants that should be the object of payment in the retributive rate. Besides the selection of the pollutants that should be in the payment, the analysis of the retributive rate structure was made witch was based on the description or four key elements the generated fact, the tax base, the passive subject, and the fee of the rate. taking into account the social costs which are related to the investment being made by the district for the treatment of patients that present acute respiratory diseases ERA´s, associated and the costs of program control and monitoring of the air quality in Bogotá, the tariffs of the payment of the retributive rate were redefined in 281 $/Kg for the PM10, 2816 $/kg for the SOX and 2866 $/kg for NOX. Finally a new model of the payment was established, which is the result of the multiplication of the respective tariff for each of the pollutants that were selected as object of payment, expressed in ($/kg times, the charge of the pollutants emitted by the source expressed in (kg/ day.times the total number of days of the operation of the source emissions in a year.

  12. A volume-limited ROSAT survey of extreme ultraviolet emission from all nondegenerate stars within 10 parsecs

    Science.gov (United States)

    Wood, Brian E.; Brown, Alexander; Linsky, Jeffrey L.; Kellett, Barry J.; Bromage, Gordon E.; Hodgkin, Simon T.; Pye, John P.

    1994-01-01

    We report the results of a volume-limited ROSAT Wide Field Camera (WFC) survey of all nondegenerate stars within 10 pc. Of the 220 known star systems within 10 pc, we find that 41 are positive detections in at least one of the two WFC filter bandpasses (S1 and S2), while we consider another 14 to be marginal detections. We compute X-ray luminosities for the WFC detections using Einstein Imaging Proportional Counter (IPC) data, and these IPC luminosities are discussed along with the WFC luminosities throughout the paper for purposes of comparison. Extreme ultraviolet (EUV) luminosity functions are computed for single stars of different spectral types using both S1 and S2 luminosities, and these luminosity functions are compared with X-ray luminosity functions derived by previous authors using IPC data. We also analyze the S1 and S2 luminosity functions of the binary stars within 10 pc. We find that most stars in binary systems do not emit EUV radiation at levels different from those of single stars, but there may be a few EUV-luminous multiple-star systems which emit excess EUV radiation due to some effect of binarity. In general, the ratio of X-ray luminosity to EUV luminosity increases with increasing coronal emission, suggesting that coronally active stars have higher coronal temperatures. We find that our S1, S2, and IPC luminosities are well correlated with rotational velocity, and we compare activity-rotation relations determined using these different luminosities. Late M stars are found to be significantly less luminous in the EUV than other late-type stars. The most natural explanation for this results is the concept of coronal saturation -- the idea that late-type stars can emit only a limited fraction of their total luminosity in X-ray and EUV radiation, which means stars with very low bolometric luminosities must have relatively low X-ray and EUV luminosities as well. The maximum level of coronal emission from stars with earlier spectral types is studied

  13. Conductivity equations of protons transporting through 2D crystals obtained with the rate process theory and free volume concept

    Science.gov (United States)

    Hao, Tian; Xu, Yuanze; Hao, Ting

    2018-04-01

    The Eyring's rate process theory and free volume concept are employed to treat protons (or other particles) transporting through a 2D (two dimensional) crystal like graphene and hexagonal boron nitride. The protons are assumed to be activated first in order to participate conduction and the conduction rate is dependent on how much free volume available in the system. The obtained proton conductivity equations show that only the number of conduction protons, proton size and packing structure, and the energy barrier associated with 2D crystals are critical; the quantization conductance is unexpectedly predicted with a simple Arrhenius type temperature dependence. The predictions agree well with experimental observations and clear out many puzzles like much smaller energy barrier determined from experiments than from the density function calculations and isotope separation rate independent of the energy barrier of 2D crystals, etc. Our work may deepen our understandings on how protons transport through a membrane and has direct implications on hydrogen related technology and proton involved bioprocesses.

  14. Dynamics of chest wall volume regulation during constant work rate exercise in patients with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Takara, L.S.; Cunha, T.M.; Barbosa, P.; Rodrigues, M.K.; Oliveira, M.F.; Nery, L.E. [Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Disciplina de Pneumologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Neder, J.A. [Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Disciplina de Pneumologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Division of Respiratory and Critical Care Medicine, Department of Medicine, Queen' s University, Kingston, ON (Canada)

    2012-10-15

    This study evaluated the dynamic behavior of total and compartmental chest wall volumes [(V{sub CW}) = rib cage (V{sub RC}) + abdomen (V{sub AB})] as measured breath-by-breath by optoelectronic plethysmography during constant-load exercise in patients with stable chronic obstructive pulmonary disease. Thirty males (GOLD stages II-III) underwent a cardiopulmonary exercise test to the limit of tolerance (Tlim) at 75% of peak work rate on an electronically braked cycle ergometer. Exercise-induced dynamic hyperinflation was considered to be present when end-expiratory (EE) V{sub CW} increased in relation to resting values. There was a noticeable heterogeneity in the patterns of V{sub CW} regulation as EEV{sub CW} increased non-linearly in 17/30 “hyperinflators” and decreased in 13/30 “non-hyperinflators” (P < 0.05). EEV{sub AB} decreased slightly in 8 of the “hyperinflators”, thereby reducing and slowing the rate of increase in end-inspiratory (EI) V{sub CW} (P < 0.05). In contrast, decreases in EEV{sub CW} in the “non-hyperinflators” were due to the combination of stable EEV{sub RC} with marked reductions in EEV{sub AB}. These patients showed lower EIV{sub CW} and end-exercise dyspnea scores but longer Tlim than their counterparts (P < 0.05). Dyspnea increased and Tlim decreased non-linearly with a faster rate of increase in EIV{sub CW} regardless of the presence or absence of dynamic hyperinflation (P < 0.001). However, no significant between-group differences were observed in metabolic, pulmonary gas exchange and cardiovascular responses to exercise. Chest wall volumes are continuously regulated during exercise in order to postpone (or even avoid) their migration to higher operating volumes in patients with COPD, a dynamic process that is strongly dependent on the behavior of the abdominal compartment.

  15. Dropout and Graduation Rates 2007-2008. Research Brief. Volume 0804

    Science.gov (United States)

    Research Services, Miami-Dade County Public Schools, 2009

    2009-01-01

    The District conducts a "cross-sectional" analysis of student dropouts annually; it examines dropout rates among students enrolled in various grades at one point in time. A "longitudinal" analysis, also conducted annually, tracks a group of students in the same grade or cohort over a period of several years. Each method…

  16. Dropout and Federal Graduation Rates 2013-2014. Research Brief. Volume 1407

    Science.gov (United States)

    Froman, Terry

    2015-01-01

    The District conducts two kinds of dropout analyses every year in Miami-Dade County Public Schools. The "cross-sectional" analysis of student dropouts examines dropout rates among students enrolled in various grades at one point in time. A "longitudinal" analysis, also conducted annually, tracks a group of students in the same…

  17. Dropout and Graduation Rates 2008-2009. Research Brief. Volume 0902

    Science.gov (United States)

    Research Services, Miami-Dade County Public Schools, 2010

    2010-01-01

    The District conducts a "cross-sectional" analysis of student dropouts annually; it examines dropout rates among students enrolled in various grades at one point in time. A "longitudinal" analysis, also conducted annually, tracks a group of students in the same grade or cohort over a period of several years. Each method…

  18. Dropout and Graduation Rates 2009-2010. Research Brief. Volume 1101

    Science.gov (United States)

    Research Services, Miami-Dade County Public Schools, 2011

    2011-01-01

    The District conducts a "cross-sectional" analysis of student dropouts annually; it examines dropout rates among students enrolled in various grades at one point in time. A "longitudinal" analysis, also conducted annually, tracks a group of students in the same grade or cohort over a period of several years. Each method…

  19. Dropout and Graduation Rates 2010-2011. Research Brief. Volume 1107

    Science.gov (United States)

    Research Services, Miami-Dade County Public Schools, 2012

    2012-01-01

    The District conducts a "cross-sectional" analysis of student dropouts annually; it examines dropout rates among students enrolled in various grades at one point in time. A "longitudinal" analysis, also conducted annually, tracks a group of students in the same grade or cohort over a period of several years. Each method…

  20. Effective diffusion volume flow rates (Qe) for urea, creatinine, and inorganic phosphorous (Qeu, Qecr, QeiP) during hemodialysis.

    Science.gov (United States)

    Gotch, Frank A; Panlilio, Froilan; Sergeyeva, Olga; Rosales, Laura; Folden, Tom; Kaysen, George; Levin, Nathan

    2003-01-01

    In vivo solute clearances can be estimated from dialyzer blood (Qb) and dialysate (Qd) flow rates and a solute- and dialyzer-specific overall permeability membrane area product (KoA). However, these calculations require knowledge of the flow rate of the effective solute distribution volume in the flowing bloodstream (Qe) in order to calculate in vivo clearances and KoAs. We have determined Qe for urea, creatinine, and inorganic phosphorus from changes in concentrations across the blood compartment and mass balance between the blood and dialysate streams. We made four serial measurements over one dialysis in 23 patients and found that Qeu equals the total blood water flow rate, Qecr equals the plasma water flow rate plus 61% of red cell water flow rate, and QeiP is limited to the plasma water flow rate. Equations are derived to calculate Qe for each of these solutes from Qb and hematocrit and in vivo KoAs for each solute were calculated.

  1. Implication on the core collapse supernova rate from 21 years of data of the Large Volume Detector

    CERN Document Server

    Agafonova, N Y; Antonioli, P; Ashikhmin, V V; Badino, G.; Bari, G; Bertoni, R; Bressan, E; Bruno, G; Dadykin, V L; Dobrynina, E A; Enikeev, R I; Fulgione, W; Galeotti, P; Garbini, M; Ghia, P L; Giusti, P; Gomez, F; Kemp, E; Malgin, A S; Molinario, A; Persiani, R; Pless, I A; Porta, A; Ryasny, V G; Ryazhskaya, O G; Saavedra, O; Sartorelli, G; Shakiryanova, I R; Selvi, M; Trinchero, G C; Vigorito, C; Yakushev, V F; Zichichi, A

    2015-01-01

    The Large Volume Detector (LVD) has been continuously taking data since 1992 at the INFN Gran Sasso National Laboratory. LVD is sensitive to neutrino bursts from gravitational stellar collapses with full detection probability over the Galaxy. We have searched for neutrino bursts in LVD data taken in 7335 days of operation. No evidence of neutrino signals has been found between June 1992 and December 2013. The 90% C.L. upper limit on the rate of core-collapse and failed supernova explosions out to distances of 25 kpc is found to be 0.114/y.

  2. Stellar mass black holes in star clusters: gravitational wave emission and detection rates

    OpenAIRE

    Banerjee, Sambaran

    2011-01-01

    We investigate the dynamics of stellar-mass black holes (BH) in star clusters focusing on the dynamical formation of BH-BH binaries, which are very important sources of gravitational waves (GW). We examine the properties of these BH-BH binaries through direct N-body computations of Plummer clusters, having initially N(0) = 5 X 10^4, typically a few of them dynamically harden to the extent that they can merge via GW emission within the cluster. Also, for each of such clusters, there are a few ...

  3. Correlation of symptom depression levels with mean platelet volume rate on patients of acute coronary syndrome

    Science.gov (United States)

    Hasugian, L.; Hanum, H.; Hanida, W.; Safri, Z.

    2018-03-01

    Patients with Depression and the acute coronary syndrome (ACS) is rarely detected, although in some studies say that depression can worsen cardiovascularly and increase mortality. From research, Canan F et al found that increasing levels of Mean platelet volume (MPV) as a risk factor for atherosclerosis and MPV was higher in patients with depression compared with patients without depression. In this study used observational methods of measurement of cross-sectional data. Research began in November 2015 - May 2016 against General Hospital inpatients H. Adam Malik Medan. There are 64 patients with a diagnosis of ACS were given quieter Beck Depression Inventory (BDI), then calculated a score of BDI patients and MPV levels were seen when they first entered the hospital before being given treatment. Patients answered quieter on days 3-7 after diagnosis ACS. ACS Patients were divided into 3 groups: acute myocardial infarction with ST elevation, acute myocardial infarction with non-ST elevation and unstable angina pectoris. The level of depression is grouped into not depression, mild depression, moderate depression and severe depression. Statistically significant with p-value<0.05Based on the linear correlation analysis, it was found a positive correlation with r=0.542. And the relationship is statistically significant with p-value 0.000003.

  4. Impact of surgical volume on functional results and cardiospecific survival rates in patients with clinically localized renal cancer

    Directory of Open Access Journals (Sweden)

    M. I. Volkova

    2014-11-01

    Full Text Available Objective: to analyze the impact of surgical volume on functional results and cardiospecific survival rates in patients with clinically localized renal carcinoma.Subjects and methods. Four hundred and fifty-three patients with pT1–3aN0M0 renal cell carcinoma and normally functioning secondkidney who had undergone radical nephrectomy (n = 226 (49.9 % or kidney resection (n = 227 (50.1 % were selected for the investigation. The patient groups who had undergone different-volume operations were matched for gender, age, body mass index (BMI, side of involvement, tumor sizes, and baseline glomerular filtration rate (GFR (p > for all. The median baseline Charlson index and the rate of ASA classes III–IV operative risk were significantly higher in candidates for radical nephrectomy (p < 0.05 for all, the rate of diseases affecting kidney function, pT1a category, and G1 anaplasia were higher in the kidney resection group (p < 0.0001. The median follow-up was 50 (12–224 months.Results. Within 28 days postsurgery, the rate of acute renal dysfunction (ARD was 36.2 %. The independent risk factors of ARD were kidney resection (risk ratio (RR = 0.210; 95 % confidence interval (CI 0.115–0.288; р < 0.0001 and ischemia time (RR = 0.012; 95 % CI 0.004–0.021; p = 0.004. The degree of ARD after kidney resection was significantly lower than that following radical nephrectomy (p < 0.0001. In the late postoperative period, the incidence of chronic kidney disease (CKD Stage ≥ III was 38.4 %. Its independent risk factors were low baseline GFR (RR = 0.003; 95 % CI 0.002–0.005; p < 0.0001, radical nephrectomy (RR = 0.195; 95 % CI 0.093–0.298; p < 0.0001, and ARD (RR = 0.281; 95 % CI 0.187–0.376; p = 0.0001. Ten-year specific and cardiospecific survival rates in all the patients were 98.5 and 94.9 %, respectively, and unrelated to surgical volume. The independent predictors of poor cardiospecific survival were BMI, Charlson index, and ASA risk

  5. Impact of surgical volume on functional results and cardiospecific survival rates in patients with clinically localized renal cancer

    Directory of Open Access Journals (Sweden)

    M. I. Volkova

    2014-01-01

    Full Text Available Objective: to analyze the impact of surgical volume on functional results and cardiospecific survival rates in patients with clinically localized renal carcinoma.Subjects and methods. Four hundred and fifty-three patients with pT1–3aN0M0 renal cell carcinoma and normally functioning secondkidney who had undergone radical nephrectomy (n = 226 (49.9 % or kidney resection (n = 227 (50.1 % were selected for the investigation. The patient groups who had undergone different-volume operations were matched for gender, age, body mass index (BMI, side of involvement, tumor sizes, and baseline glomerular filtration rate (GFR (p > for all. The median baseline Charlson index and the rate of ASA classes III–IV operative risk were significantly higher in candidates for radical nephrectomy (p < 0.05 for all, the rate of diseases affecting kidney function, pT1a category, and G1 anaplasia were higher in the kidney resection group (p < 0.0001. The median follow-up was 50 (12–224 months.Results. Within 28 days postsurgery, the rate of acute renal dysfunction (ARD was 36.2 %. The independent risk factors of ARD were kidney resection (risk ratio (RR = 0.210; 95 % confidence interval (CI 0.115–0.288; р < 0.0001 and ischemia time (RR = 0.012; 95 % CI 0.004–0.021; p = 0.004. The degree of ARD after kidney resection was significantly lower than that following radical nephrectomy (p < 0.0001. In the late postoperative period, the incidence of chronic kidney disease (CKD Stage ≥ III was 38.4 %. Its independent risk factors were low baseline GFR (RR = 0.003; 95 % CI 0.002–0.005; p < 0.0001, radical nephrectomy (RR = 0.195; 95 % CI 0.093–0.298; p < 0.0001, and ARD (RR = 0.281; 95 % CI 0.187–0.376; p = 0.0001. Ten-year specific and cardiospecific survival rates in all the patients were 98.5 and 94.9 %, respectively, and unrelated to surgical volume. The independent predictors of poor cardiospecific survival were BMI, Charlson index, and ASA risk

  6. Modeling the effects of auxiliary gas injection and fuel injection rate shape on diesel engine combustion and emissions

    Science.gov (United States)

    Mather, Daniel Kelly

    1998-11-01

    The effect of auxiliary gas injection and fuel injection rate-shaping on diesel engine combustion and emissions was studied using KIVA a multidimensional computational fluid dynamics code. Auxiliary gas injection (AGI) is the injection of a gas, in addition to the fuel injection, directly into the combustion chamber of a diesel engine. The objective of AGI is to influence the diesel combustion via mixing to reduce emissions of pollutants (soot and NO x). In this study, the accuracy of modeling high speed gas jets on very coarse computational grids was addressed. KIVA was found to inaccurately resolve the jet flows near walls. The cause of this inaccuracy was traced to the RNG k - ɛ turbulence model with the law-of-the-wall boundary condition used by KIVA. By prescribing the lengthscale near the nozzle exit, excellent agreement between computed and theoretical jet penetration was attained for a transient gas jet into a quiescent chamber at various operating conditions. The effect of AGI on diesel engine combustion and emissions was studied by incorporating the coarse grid gas jet model into a detailed multidimensional simulation of a Caterpillar 3401 heavy-duty diesel engine. The effects of AGI timing, composition, amount, orientation, and location were investigated. The effects of AGI and split fuel injection were also investigated. AGI was found to be effective at reducing soot emissions by increasing mixing within the combustion chamber. AGI of inert gas was found to be effective at reducing emissions of NOx by depressing the peak combustion temperatures. Finally, comparison of AGI simulations with experiments were conducted for a TACOM-LABECO engine. The results showed that AGI improved soot oxidation throughout the engine cycle. Simulation of fuel injection rate-shaping investigated the effects of three injection velocity profiles typical of unit-injector type, high-pressure common-rail type, and accumulator-type fuel injectors in the Caterpillar 3401 heavy

  7. Hazardous air pollutant emissions from process units in the synthetic organic chemical manufacturing industry: Background information for proposed standards. Volume 1B. Control technologies. Draft report

    International Nuclear Information System (INIS)

    1992-11-01

    A draft rule for the regulation of emissions of organic hazardous air pollutants (HAP's) from chemical processes of the synthetic organic chemical manufacturing industry (SOCMI) is being proposed under the authority of Sections 112, 114, 116, and 301 of the Clean Air Act, as amended in 1990. The volume of the Background Information Document presents discussions of control technologies used in the industry and the costs of those technologies

  8. Hazardous air pollutant emissions from process units in the synthetic organic chemical manufacturing industry: Background information for proposed standards. Volume 1A. National impacts assessment. Draft report

    International Nuclear Information System (INIS)

    1992-11-01

    A draft rule for the regulation of emissions of organic hazardous air pollutants (HAP's) from chemical processes of the synthetic organic chemical manufacturing industry (SOCMI) is being proposed under the authority of Sections 112, 114, 116, and 301 of the Clean Air Act, as amended in 1990. The volume of the Background Information Document presents the results of the national impacts assessment for the proposed rule

  9. Determination of the disintegration rate and gamma emission probabilities per decay of 182 Ta

    International Nuclear Information System (INIS)

    Silva, Eliezer Antonio da

    2008-01-01

    In this work the procedure developed for the standardization of 182 Ta sources produced by irradiation at the IPEN IEA-R1 research reactor is presented. The 182 Ta decays with a half-life of 114 days by β - emission, populating the excited levels of 182 W. It emits gamma rays with several energies mainly between 31 keV and 264 keV and between 1001 keV and 1453 keV. The measurements were performed in a 4πβ-γ coincidence system by using the extrapolation technique. The coincidence system is composed of a 4 π proportional counter coupled to a NaI(Tl) cristal. The measurements were undertaken selecting two windows in the γ-channel, in order to check the consistency of the results. A Monte Carlo calculation was performed in order to predict the behavior of the observed activity as a function of 4πβ the detector efficiency and the results were compared to experimental values. The most intense gamma-ray emission probabilities of 182 Ta were determined by means of an HPGe gamma spectrometer, the germanium efficiency curve was obtained by using sources 152 Eu, 241 Am, 60 Co, 133 Ba and 166m Ho standardized in a primary system. The uncertainties involved in the measurements were treated by the covariance methodology. The results obtained are in good agreement with the experimental uncertainty compared with literature values. (author)

  10. U duality, D-branes, and black hole emission rates: Agreements and disagreements

    International Nuclear Information System (INIS)

    Dowker, F.; Kastor, D.; Traschen, J.

    1998-01-01

    An expression for the spacetime absorption coefficient of a scalar field in a five-dimensional, near-extremal black hole background is derived, which has the same form as that presented by Maldacena and Strominger, but is valid over a larger, U-duality invariant region of parameter space and in general disagrees with the corresponding D-brane result. We develop an argument, based on D-brane thermodynamics, which specifies the range of parameters over which agreement should be expected. For neutral emission, the spacetime and D-brane results agree over this range. However, for charged emission, we find disagreement in the 'fat black hole' regime, in which charge is quantized in smaller units on the brane than in the bulk of spacetime. We indicate a possible problem with the D-brane model in this regime. We also use the Born approximation to study the high frequency limit of the absorption coefficient and find that it approaches unity, for large black hole backgrounds, at frequencies still below the string scale, again in disagreement with D-brane results. copyright 1998 The American Physical Society

  11. Performance and emission studies on port injection of hydrogen with varied flow rates with Diesel as an ignition source

    International Nuclear Information System (INIS)

    Saravanan, N.; Nagarajan, G.

    2010-01-01

    Automobiles are one of the major sources of air pollution in the environment. In addition CO 2 emission, a product of complete combustion also has become a serious issue due to global warming effect. Hence the search for cleaner alternative fuels has become mandatory. Hydrogen is expected to be one of the most important fuels in the near future for solving the problems of air pollution and greenhouse gas problems (carbon dioxide), thereby protecting the environment. Hence in the present work, an experimental investigation has been carried out using hydrogen in the dual fuel mode in a Diesel engine system. In the study, a Diesel engine was converted into a dual fuel engine and hydrogen fuel was injected into the intake port while Diesel was injected directly inside the combustion chamber during the compression stroke. Diesel injected inside the combustion chamber will undergo combustion first which in-turn would ignite the hydrogen that will also assist the Diesel combustion. Using electronic control unit (ECU), the injection timings and injection durations were varied for hydrogen injection while for Diesel the injection timing was 23 o crank angle (CA) before injection top dead centre (BITDC). Based on the performance, combustion and emission characteristics, the optimized injection timing was found to be 5 o CA before gas exchange top dead centre (BGTDC) with injection duration of 30 o CA for hydrogen Diesel dual fuel operation. The optimum hydrogen flow rate was found to be 7.5 lpm. Results indicate that the brake thermal efficiency in hydrogen Diesel dual fuel operation increases by 15% compared to Diesel fuel at 75% load. The NO X emissions were higher by 1-2% in dual fuel operation at full load compared to Diesel. Smoke emissions are lower in the entire load spectra due to the absence of carbon in hydrogen fuel. The carbon monoxide (CO), carbon dioxide (CO 2 ) emissions were lesser in hydrogen Diesel dual fuel operation compared to Diesel. The use of hydrogen

  12. Performance and emission studies on port injection of hydrogen with varied flow rates with Diesel as an ignition source

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, N. [ERC Engines, Tata Motors, Pimpri, Pune (India); Nagarajan, G. [Internal Combustion Engineering Division, Department of Mechanical Engineering, College of Engineering, Guindy, Anna University, Chennai (India)

    2010-07-15

    Automobiles are one of the major sources of air pollution in the environment. In addition CO{sub 2} emission, a product of complete combustion also has become a serious issue due to global warming effect. Hence the search for cleaner alternative fuels has become mandatory. Hydrogen is expected to be one of the most important fuels in the near future for solving the problems of air pollution and greenhouse gas problems (carbon dioxide), thereby protecting the environment. Hence in the present work, an experimental investigation has been carried out using hydrogen in the dual fuel mode in a Diesel engine system. In the study, a Diesel engine was converted into a dual fuel engine and hydrogen fuel was injected into the intake port while Diesel was injected directly inside the combustion chamber during the compression stroke. Diesel injected inside the combustion chamber will undergo combustion first which in-turn would ignite the hydrogen that will also assist the Diesel combustion. Using electronic control unit (ECU), the injection timings and injection durations were varied for hydrogen injection while for Diesel the injection timing was 23 crank angle (CA) before injection top dead centre (BITDC). Based on the performance, combustion and emission characteristics, the optimized injection timing was found to be 5 CA before gas exchange top dead centre (BGTDC) with injection duration of 30 CA for hydrogen Diesel dual fuel operation. The optimum hydrogen flow rate was found to be 7.5 lpm. Results indicate that the brake thermal efficiency in hydrogen Diesel dual fuel operation increases by 15% compared to Diesel fuel at 75% load. The NO{sub X} emissions were higher by 1-2% in dual fuel operation at full load compared to Diesel. Smoke emissions are lower in the entire load spectra due to the absence of carbon in hydrogen fuel. The carbon monoxide (CO), carbon dioxide (CO{sub 2}) emissions were lesser in hydrogen Diesel dual fuel operation compared to Diesel. The use of

  13. Efficient Rectangular Maximal-Volume Algorithm for Rating Elicitation in Collaborative Filtering

    KAUST Repository

    Fonarev, Alexander

    2017-02-07

    Cold start problem in Collaborative Filtering can be solved by asking new users to rate a small seed set of representative items or by asking representative users to rate a new item. The question is how to build a seed set that can give enough preference information for making good recommendations. One of the most successful approaches, called Representative Based Matrix Factorization, is based on Maxvol algorithm. Unfortunately, this approach has one important limitation - a seed set of a particular size requires a rating matrix factorization of fixed rank that should coincide with that size. This is not necessarily optimal in the general case. In the current paper, we introduce a fast algorithm for an analytical generalization of this approach that we call Rectangular Maxvol. It allows the rank of factorization to be lower than the required size of the seed set. Moreover, the paper includes the theoretical analysis of the method\\'s error, the complexity analysis of the existing methods and the comparison to the state-of-the-art approaches.

  14. Pollutant Concentrations and Emission Rates from Scripted Natural Gas Cooking Burner Use in Nine Northern California Homes

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Delp, William W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lorenzetti, David M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Maddalena, Randy L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-10-01

    in the kitchen and bedroom of several homes. A hood with large capture volume and a measured flow of 108 L/s reduced concentrations 80-95%. IMPLICATIONS: These measurements demonstrate that operation of natural gas cooking burners without venting can cause short-term kitchen concentrations of NO2 to exceed the US outdoor health standard, and can elevate concentrations of NO, NO2, and ultrafine particles throughout the home. Results are generally consistent with a recent simulation study that estimated widespread 1h NO2 exposures exceeding 100 ppb in homes that use gas burners without venting. While operating a venting range hood can greatly reduce pollutant levels from burner use (and presumably from cooking as well), performance varies widely across hoods. Increased awareness of the need to ventilate when cooking would substantially reduce in-home exposure to NO2 and ultrafine particles in California homes. Helping consumers select effective hoods, for example by publishing capture efficiency performance ratings, also would help reduce exposure.

  15. Tap density equations of granular powders based on the rate process theory and the free volume concept.

    Science.gov (United States)

    Hao, Tian

    2015-02-28

    The tap density of a granular powder is often linked to the flowability via the Carr index that measures how tight a powder can be packed, under an assumption that more easily packed powders usually flow poorly. Understanding how particles are packed is important for revealing why a powder flows better than others. There are two types of empirical equations that were proposed to fit the experimental data of packing fractions vs. numbers of taps in the literature: the inverse logarithmic and the stretched exponential. Using the rate process theory and the free volume concept under the assumption that particles will obey similar thermodynamic laws during the tapping process if the "granular temperature" is defined in a different way, we obtain the tap density equations, and they are reducible to the two empirical equations currently widely used in literature. Our equations could potentially fit experimental data better with an additional adjustable parameter. The tapping amplitude and frequency, the weight of the granular materials, and the environmental temperature are grouped into this parameter that weighs the pace of the packing process. The current results, in conjunction with our previous findings, may imply that both "dry" (granular) and "wet" (colloidal and polymeric) particle systems are governed by the same physical mechanisms in term of the role of the free volume and how particles behave (a rate controlled process).

  16. CT contrasting theory. Effects of the concentration, volume and infusion rate of iodine contrast medium on TDC

    International Nuclear Information System (INIS)

    Yamachi, Jun

    2007-01-01

    This study was performed to evaluate the effects in the title on TDC (time-density curve) using a phantom. CT machine used was Toshiba Aquilion Multi 64, TDC phantom was the product of Nemoto-Kyorindo Co., and the contrast medium was Eisai iomeprol, in syringe-sealed formulations of 300 and 350 mg I/mL. The medium was infused at 1-5 mL/sec in the phantom equivalent to body weight of 78 kg (total water volume=1 min circulation=6,000 mL, 800 mL/heart) to obtain 30 TDCs. Evaluated were the relationships of the infusion rate (mL/sec), volume (mL) or time (sec) with TDC parameters of the detection time of the medium, slope, time to reach the maximum CT value, the maximum CT value, time to keep the CT concentration and its actual concentration. Results revealed that, regardless to the difference of formulations of the contrast medium, TDC with high reproducibility can be obtainable by making the infusion rate of I per unit time and body weight (mgI/sec/kg) constant when the infusion time is made identical for CT of the same diagnostic purpose. (R.T.)

  17. Effect of partial volume correction on muscarinic cholinergic receptor imaging with single-photon emission tomography in patients with temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Weckesser, M.; Ziemons, K.; Griessmeier, M.; Sonnenberg, F.; Langen, K.J.; Mueller-Gaertner, H.W.; Hufnagel, A.; Elger, C.E.; Hacklaender, T.; Holschbach, M.

    1997-01-01

    Animal experiments and preliminary results in humans have indicated alterations of hippocampal muscarinic acetylcholine receptors (mAChR) in temporal lobe epilepsy. Patients with temporal lobe epilepsy often present with a reduction in hippocampal volume. The aim of this study was to investigate the influence of hippocampal atrophy on the quantification of mAChR with single photon emission tomography (SPET) in patients with temporal lobe epilepsy. Cerebral uptake of the muscarinic cholinergic antagonist [ 123 I]4-iododexetimide (IDex) was investigated by SPET in patients suffering from temporal lobe epilepsy of unilateral (n=6) or predominantly unilateral (n=1) onset. Regions of interest were drawn on co-registered magnetic resonance images. Hippocampal volume was determined in these regions and was used to correct the SPET results for partial volume effects. A ratio of hippocampal IDex binding on the affected side to that on the unaffected side was used to detect changes in muscarinic cholinergic receptor density. Before partial volume correction a decrease in hippocampal IDex binding on the focus side was found in each patient. After partial volume no convincing differences remained. Our results indicate that the reduction in hippocampal IDex binding in patients with epilepsy is due to a decrease in hippocampal volume rather than to a decrease in receptor concentration. (orig.). With 2 figs., 2 tabs

  18. A review of chamber experiments for determining specific emission rates and investigating migration pathways of flame retardants

    Science.gov (United States)

    Rauert, Cassandra; Lazarov, Borislav; Harrad, Stuart; Covaci, Adrian; Stranger, Marianne

    2014-01-01

    The widespread use of flame retardants (FRs) in indoor products has led to their ubiquitous distribution within indoor microenvironments with many studies reporting concentrations in indoor air and dust. Little information is available however on emission of these compounds to air, particularly the measurement of specific emission rates (SERs), or the migration pathways leading to dust contamination. Such knowledge gaps hamper efforts to develop understanding of human exposure. This review summarizes published data on SERs of the following FRs released from treated products: polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), tetrabromobisphenol-A (TBBPA), novel brominated flame retardants (NBFRs) and organophosphate flame retardants (PFRs), including a brief discussion of the methods used to derive these SERs. Also reviewed are published studies that utilize emission chambers for investigations/measurements of mass transfer of FRs to dust, discussing the chamber configurations and methods used for these experiments. A brief review of studies investigating correlations between concentrations detected in indoor air/dust and possible sources in the microenvironment is included along with efforts to model contamination of indoor environments. Critical analysis of the literature reveals that the major limitations with utilizing chambers to derive SERs for FRs arise due to the physicochemical properties of FRs. In particular, increased partitioning to chamber surfaces, airborne particles and dust, causes loss through “sink” effects and results in long times to reach steady state conditions inside the chamber. The limitations of chamber experiments are discussed as well as their potential for filling gaps in knowledge in this area.

  19. Blinded by the light: on the relationship between CO first overtone emission and mass accretion rate in massive young stellar objects

    Science.gov (United States)

    Ilee, J. D.; Oudmaijer, R. D.; Wheelwright, H. E.; Pomohaci, R.

    2018-04-01

    To date, there is no explanation as to why disc-tracing CO first overtone (or `bandhead') emission is not a ubiquitous feature in low- to medium-resolution spectra of massive young stellar objects, but instead is only detected toward approximately 25 per cent of their spectra. In this paper, we investigate the hypothesis that only certain mass accretion rates result in detectable bandhead emission in the near infrared spectra of MYSOs. Using an analytic disc model combined with an LTE model of the CO emission, we find that high accretion rates (≳ 10-4 M⊙yr-1) result in large dust sublimation radii, a larger contribution to the K-band continuum from hot dust at the dust sublimation radius, and therefore correspondingly lower CO emission with respect to the continuum. On the other hand, low accretion rates (≲ 10-6 M⊙yr-1) result in smaller dust sublimation radii, a correspondingly smaller emitting area of CO, and thus also lower CO emission with respect to the continuum. In general, moderate accretion rates produce the most prominent, and therefore detectable, CO first overtone emission. We compare our findings to a recent near-infrared spectroscopic survey of MYSOs, finding results consistent with our hypothesis. We conclude that the detection rate of CO bandhead emission in the spectra of MYSOs could be the result of MYSOs exhibiting a range of mass accretion rates, perhaps due to the variable accretion suggested by recent multi-epoch observations of these objects.

  20. Environmental effects of energy production and utilization in the U.S. Volume 3. Techniques for controlling emissions

    International Nuclear Information System (INIS)

    Newkirk, H.W.

    1976-01-01

    Technological, social, economic and political techniques for controlling emission are summarized for environmental pollutants introduced into air, water and land resources. Chemical, radiological and physical factors are discussed

  1. Positron emission tomography assessment of cerebral glucose metabolic rates in autism spectrum disorder and schizophrenia.

    Science.gov (United States)

    Mitelman, Serge A; Bralet, Marie-Cecile; Mehmet Haznedar, M; Hollander, Eric; Shihabuddin, Lina; Hazlett, Erin A; Buchsbaum, Monte S

    2018-04-01

    Several models have been proposed to account for observed overlaps in clinical features and genetic predisposition between schizophrenia and autism spectrum disorder. This study assessed similarities and differences in topological patterns and vectors of glucose metabolism in both disorders in reference to these models. Co-registered 18 fluorodeoxyglucose PET and MRI scans were obtained in 41 schizophrenia, 25 ASD, and 55 healthy control subjects. AFNI was used to map cortical and subcortical regions of interest. Metabolic rates were compared between three diagnostic groups using univariate and multivariate repeated-measures ANOVA. Compared to controls, metabolic rates in schizophrenia subjects were decreased in the frontal lobe, anterior cingulate, superior temporal gyrus, amygdala and medial thalamic nuclei; rates were increased in the occipital cortex, hippocampus, basal ganglia and lateral thalamic nuclei. In ASD subjects metabolic rates were decreased in the parietal lobe, frontal premotor and eye-fields areas, and amygdala; rates were increased in the posterior cingulate, occipital cortex, hippocampus and basal ganglia. In relation to controls, subjects with ASD and schizophrenia showed opposite changes in metabolic rates in the primary motor and somatosensory cortex, anterior cingulate and hypothalamus; similar changes were found in prefrontal and occipital cortices, inferior parietal lobule, amygdala, hippocampus, and basal ganglia. Schizophrenia and ASD appear to be associated with a similar pattern of metabolic abnormalities in the social brain. Divergent maladaptive trade-offs, as postulated by the diametrical hypothesis of their evolutionary relationship, may involve a more circumscribed set of anterior cingulate, motor and somatosensory regions and the specific cognitive functions they subserve.

  2. A comparison between the order and the volume fill rate for a base-stock inventory control system under a compound renewal demand process

    DEFF Research Database (Denmark)

    Larsen, Christian; Thorstenson, Anders

    2008-01-01

    The order fill rate (OFR) is sometimes suggested as an alternative to the volume fill rate (VFR) (most often just denoted fill rate) as a performance measure for inventory control systems. We consider a continuous review, base-stock policy, where replenishment orders have a constant lead time...

  3. Latex paint as a delivery vehicle for diethylphthalate and di-n-butylphthalate: predictable boundary layer concentrations and emission rates.

    Science.gov (United States)

    Schripp, Tobias; Salthammer, Tunga; Fauck, Christian; Bekö, Gabriel; Weschler, Charles J

    2014-10-01

    The description of emission processes of volatile and semi-volatile organic compounds (VOCs and SVOCs) from building products requires a detailed understanding of the material and the air flow conditions at the surface boundary. The mass flux between the surface of the material and air depends on the mass transfer coefficient (hm) through the boundary layer, the gas phase concentration of the target compound immediately adjacent to the material (y0), and the gas-phase concentration in bulk air (y(t)). In the present study emission experiments were performed in two chambers of quite different sizes (0.25 m(3) and 55 m(3)), and, in the larger chamber, at two different temperatures (23°C and 30°C). The emitting material was latex wall paint that had been doped with two plasticizers, diethylphthalate (DEP) and di-n-butylphthalate (DnBP). The phthalate content in the paint was varied in the small chamber experiment to evaluate the impact of the initial concentration in the bulk material (C0) on the emission rate. Boundary layer theory was applied to calculate hm for the specific phthalates from the Sherwood number (Sh) and the diffusion coefficient (Dair). Then y0 was determined based on the bulk gas-phase concentration at steady state (y¯). For both, DEP and DnBP, the y0 obtained was lower than the respective saturation vapor pressure (Ps). Furthermore, for both phthalates in latex paint, the material/air partition coefficient (C0/y0) was close in value to the octanol/air partition coefficient (KOA). This study provides a basis for designing phthalate emitting reference materials that mimic the emission behavior of common building materials. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Relationship between ischemic ST depression pattern and coronary blood volume. Study using 13NH3 positron emission computed tomography under light exercise

    International Nuclear Information System (INIS)

    Watabe, Takuya; Okazaki, Osamu; Michihata, Tetsuo; Hara, Toshihiko; Harumi, Kenichi; Akutsu, Yasushi; Yamanaka, Hideyuki; Katagiri, Takashi.

    1994-01-01

    To determine the relationship between ST depression pattern and coronary blood volume in exercise induced myocardial ischemia, exercise-induced ST changes on ECG and regional myocardial blood flow (RMBF) on positron emission computed tomography (PET) were examined. The subjects were 41 patients with myocardial infarction and 30 with angina pectoris, consisting of 55 men and 16 women. Five normal men served as controls. In the group of ST depression, maximum PRP and age were significantly high, and patients with multiple vessel disease accounted for 63.6%. RMBF, as shown on PET, increased by 10% or more after exercise in 71.1% in the group of non ST change and in the control group. In 60.6% of the patients having ST depression, there was a decrease in RMBF or an unfavorable increase in RMBF. Among 33 patients in the group of ST depression, 17 had a sagging type. Of these 17, 12 (70.6%) showed a decrease of RMBF or an unfavorable increase in RMBF, and 10 had triple vessel disease. Sixteen patients had a horizontal type, 8 of whom (50.0%) had a decrease or unfavorable increase in RMBF. These findings suggest that a decrease or unfavorable increase (an increased rate of 10% or less) may be involved in the occurrence of ST depression induced by exercise. In particular, patients with a sagging type ST depression should be monitored during exercise because many of these patients may have triple vessel disease and a decrease or unfavorable increase in RMBF. (N.K.)

  5. Masked volume wise principal component analysis of small adrenocortical tumours in dynamic [11C]-metomidate positron emission tomography

    International Nuclear Information System (INIS)

    Razifar, Pasha; Hennings, Joakim; Monazzam, Azita; Hellman, Per; Långström, Bengt; Sundin, Anders

    2009-01-01

    In previous clinical Positron Emission Tomography (PET) studies novel approaches for application of Principal Component Analysis (PCA) on dynamic PET images such as Masked Volume Wise PCA (MVW-PCA) have been introduced. MVW-PCA was shown to be a feasible multivariate analysis technique, which, without modeling assumptions, could extract and separate organs and tissues with different kinetic behaviors into different principal components (MVW-PCs) and improve the image quality. In this study, MVW-PCA was applied to 14 dynamic 11C-metomidate-PET (MTO-PET) examinations of 7 patients with small adrenocortical tumours. MTO-PET was performed before and 3 days after starting per oral cortisone treatment. The whole dataset, reconstructed by filtered back projection (FBP) 0–45 minutes after the tracer injection, was used to study the tracer pharmacokinetics. Early, intermediate and late pharmacokinetic phases could be isolated in this manner. The MVW-PC1 images correlated well to the conventionally summed image data (15–45 minutes) but the image noise in the former was considerably lower. PET measurements performed by defining 'hot spot' regions of interest (ROIs) comprising 4 contiguous pixels with the highest radioactivity concentration showed a trend towards higher SUVs when the ROIs were outlined in the MVW-PC1 component than in the summed images. Time activity curves derived from '50% cut-off' ROIs based on an isocontour function whereby the pixels with SUVs between 50 to 100% of the highest radioactivity concentration were delineated, showed a significant decrease of the SUVs in normal adrenal glands and in adrenocortical adenomas after cortisone treatment. In addition to the clear decrease in image noise and the improved contrast between different structures with MVW-PCA, the results indicate that the definition of ROIs may be more accurate and precise in MVW-PC1 images than in conventional summed images. This might improve the precision of PET

  6. Tumor Volume Reduction Rate Measured by Magnetic Resonance Volumetry Correlated With Pathologic Tumor Response of Preoperative Chemoradiotherapy for Rectal Cancer

    International Nuclear Information System (INIS)

    Yeo, Seung-Gu; Kim, Dae Yong; Kim, Tae Hyun; Jung, Kyung Hae; Hong, Yong Sang; Chang, Hee Jin; Park, Ji Won; Lim, Seok-Byung; Choi, Hyo Seong; Jeong, Seung-Yong

    2010-01-01

    Purpose: To determine whether the tumor volume reduction rate (TVRR) measured using three-dimensional region-of-interest magnetic resonance volumetry correlates with the pathologic tumor response after preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer. Methods and Materials: The study included 405 patients with locally advanced rectal cancer (cT3-T4) who had undergone preoperative CRT and radical proctectomy. The tumor volume was measured using three-dimensional region-of-interest magnetic resonance volumetry before and after CRT but before surgery. We analyzed the correlation between the TVRR and the pathologic tumor response in terms of downstaging and tumor regression grade (TRG). Downstaging was defined as ypStage 0-I (ypT0-T2N0M0), and the TRG proposed by Dworak et al. was used. Results: The mean TVRR was 65.0% ± 22.3%. Downstaging and complete regression occurred in 167 (41.2%) and 58 (14.3%) patients, respectively. The TVRRs according to ypT classification (ypT0-T2 vs. ypT3-T4), ypN classification (ypN0 vs. ypN1-N2), downstaging (ypStage 0-I vs. ypStage II-III), good regression (TRG 3-4 vs. TRG 1-2), and complete regression (TRG 4 vs. TRG 1-3) were all significantly different (p 80%), the rates of ypT0-T2, ypN0, downstaging, and good regression were all significantly greater for patients with a TVRR of ≥60%, as was the complete regression rate for patients with a TVRR >80% (p <.05). Conclusion: The TVRR measured using three-dimensional region-of-interest magnetic resonance volumetry correlated significantly with the pathologic tumor response in terms of downstaging and TRG after preoperative CRT for locally advanced rectal cancer.

  7. A method of estimating inspiratory flow rate and volume from an inhaler using acoustic measurements

    International Nuclear Information System (INIS)

    Holmes, Martin S; D'Arcy, Shona; O'Brien, Ultan; Reilly, Richard B; Seheult, Jansen N; Geraghty, Colm; Costello, Richard W; Crispino O'Connell, Gloria

    2013-01-01

    Inhalers are devices employed to deliver medication to the airways in the treatment of respiratory diseases such as asthma and chronic obstructive pulmonary disease. A dry powder inhaler (DPI) is a breath actuated inhaler that delivers medication in dry powder form. When used correctly, DPIs improve patients' clinical outcomes. However, some patients are unable to reach the peak inspiratory flow rate (PIFR) necessary to fully extract the medication. Presently clinicians have no reliable method of objectively measuring PIFR in inhalers. In this study, we propose a novel method of estimating PIFR and also the inspiratory capacity (IC) of patients' inhalations from a commonly used DPI, using acoustic measurements. With a recording device, the acoustic signal of 15 healthy subjects using a DPI over a range of varying PIFR and IC values was obtained. Temporal and spectral signal analysis revealed that the inhalation signal contains sufficient information that can be employed to estimate PIFR and IC. It was found that the average power (P ave ) in the frequency band 300–600 Hz had the strongest correlation with PIFR (R 2 = 0.9079), while the power in the same frequency band was also highly correlated with IC (R 2 = 0.9245). This study has several clinical implications as it demonstrates the feasibility of using acoustics to objectively monitor inhaler use. (paper)

  8. Fundamental limitations in spontaneous emission rate of single-photon sources

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Khurgin, Jacob B.

    2016-01-01

    The rate of single-photon generation by quantum emitters (QEs) can be enhanced by placing a QE inside a resonant structure. This structure can represent an all-dielectric micro-resonator or waveguide and thus be characterized by ultra-low loss and dimensions on the order of wavelength. Or it can ...

  9. Electron impact collision strengths and transition rates for extreme ultraviolet emission from Xe10+

    International Nuclear Information System (INIS)

    Shen Yunfeng; Gao Cheng; Zeng Jiaolong

    2009-01-01

    The energy levels, oscillator strengths, and electron impact collision strengths are calculated for the Xe 10+ ion using the configuration interaction scheme implemented by the Flexible Atomic Code. These data pertain to the 3917 levels belonging to the following configurations: 4s 2 4p 6 4d 8 , 4s 2 4p 6 4d 7 4f, 4s 2 4p 6 4d 7 5l (l = s, p, d, or f), 4s 2 4p 5 4d 9 , 4s 2 4p 5 4d 8 4f, 4s 2 4p 5 4d 8 5l, 4s 2 4p 6 4d 6 5s5p, 4s 2 4p 6 4d 6 5p5d. Configuration interactions among these configurations are included in the calculation. Collision strengths are obtained at 10 scattered electron energies (1-1000 eV) and are tabulated here at five representative energies of 10, 50, 100, 500, and 1000 eV. Effective collision strengths are obtained by assuming a Maxwellian electron velocity distribution at 10 temperatures ranging from 10 to 100 eV, and are tabulated at five representative temperatures of 10, 30, 50, 70 and 100 eV in this work. The whole data set should be useful for research involving extreme ultraviolet emission from Xe 10+

  10. Electric field enhancement of electron emission rates from Z1/2 centers in 4H-SiC

    International Nuclear Information System (INIS)

    Evwaraye, A. O.; Smith, S. R.; Mitchel, W. C.; Farlow, G. C.

    2009-01-01

    Z 1/2 defect centers were produced by irradiating 4H-SiC bulk samples with 1 MeV electrons at room temperature. The emission rate dependence on the electric field in the depletion region was measured using deep level transient spectroscopy and double-correlation deep level transient spectroscopy. It is found that the Z 1/2 defect level shows a strong electric field dependence with activation energy decreasing from E c -0.72 eV at zero field to E c -0.47 eV at 6.91x10 5 V/cm. The phonon assisted tunneling model of Karpus and Perel [Sov. Phys. JETP 64, 1376 (1986)] completely describes the experimental data. This model describes the dependence of the emission rate on electric field F as e n (F)=e no exp(F 2 /F c 2 ), where F c is the characteristic field that depends on the phonon assisted tunneling time τ 2 . The values of F c and τ 2 were determined and the analysis of the data leads to the suggestion that Z 1/2 may be a substitutional point defect.

  11. CRITERIA POLLUTANT EMISSIONS FROM INTERNAL COMBUSTION ENGINES IN THE NATURAL GAS INDUSTRY VOLUME II. APPENDICES A-I

    Science.gov (United States)

    The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...

  12. New proposal to measure NO2 formation rate from NO emissions in the atmosphere

    International Nuclear Information System (INIS)

    Frins, Erna; Osorio, MatIas; Casaballe, Nicolas; Wagner, Thomas; Platt, Ulrich

    2011-01-01

    As result from combustion processes, SO 2 , NO, NO 2 and other substances are emitted in the atmosphere. We present a new method to measure the formation rate of a trace gas (e.g., NO 2 ), whose precursor (NO) was emitted in the atmosphere by a source like a stack. In the case under study, the presence of ozone determines the formation of NO 2 . We will demonstrate that measuring the slant column densities across the emitted plume and knowing the flux of another trace gas (e.g. SO 2 ), also emitted by the source but that could be considered stable under the conditions of the observation, it is possible to monitor remotely (from an arbitrary location) the formation rate of NO 2 due to conversion of NO to NO 2 .

  13. Electron-impact excitation rate-coefficients and polarization of subsequent emission for Ar"+ ion

    International Nuclear Information System (INIS)

    Dipti; Srivastava, Rajesh

    2016-01-01

    Electron impact excitation in Ar"+ ions has been studied by using fully relativistic distorted wave theory. Calculations are performed to obtain the excitation cross-sections and rate-coefficients for the transitions from the ground state 3p"5 (J=3/2) to fine-structure levels of excited states 3p"44s, 3p"44p, 3p"45s, 3p"45p, 3p"43d and 3p"44d. Polarization of the radiation following the excitation has been calculated using the obtained magnetic sub-level cross-sections. Comparison of the present rate-coefficients is also done with the previously reported theoretical results for some unresolved fine structure transitions. - Highlights: • Fully relativistic distorted wave theory has been used to study the excitation of fine-structure states of Ar"+. • We have calculated electron-impact excitation cross-sections for the wide range of incident electron energies. • Electron impact excitation rate-coefficients are calculated as a function of electron temperature. • Polarization of photons emitted following the decay of the excited fine-structure states are also reported.

  14. Blood flow and blood volume in the femoral heads of healthy adults according to age. Measurement with positron emission tomography (PET)

    International Nuclear Information System (INIS)

    Kubo, Toshikazu; Kimori, Kokuto; Nakamura, Fuminori; Inoue, Shigehiro; Fujioka, Mikihiro; Ueshima, Keiichiro; Hirasawa, Yasusuke; Ushijima, Yo; Nishimura, Tsunehiko

    2001-01-01

    To deepen understanding of hemodynamics in the femoral head, i.e., the essential factor in clarifying pathogenesis of hip disorders, this study examined blood flow and blood volume in the femoral heads of healthy adults, and their changes with age, by using positron emission tomography (PET). In 16 healthy adult males (age: 20-78 years old, mean age: 42 years), blood flow was measured by means of the H 2 15 O dynamic study method, and blood volume was measured by means of the 15 O-labeled carbon monoxide bolus inhalation method. Blood flow was 1.68-6.47 ml/min/100 g (mean ±SD: 3.52±1.2), and blood volume was 1.67-6.03 ml/100 g (mean ±SD: 3.00±1.27). Blood flow significantly decreased (p<0.01) with age, and blood volume significantly increased (P<0.05). PET was useful in the measurement of blood flow and blood volume in the femoral heads. With age, physiological hemodynamic changes also increased in femoral heads. (author)

  15. Effects of Acute Ozone Exposure and Methyl Jasmonate Treatment on White Pine Monoterpene and Sesquiterpene Emission Rates

    Science.gov (United States)

    Faiola, C. L.; Wagner, D.; Allwine, E.; Harley, P. C.; Vanreken, T. M.

    2010-12-01

    Biogenic volatile organic compounds (BVOCs) are produced by plants and include monoterpenes, sesquiterpenes, and their oxygenated derivatives. These BVOCs are one of the principal factors influencing the oxidative capacity of the atmosphere in forested regions, and impact both ozone concentration and secondary organic aerosol formation. Under unstressed conditions, the release of BVOCs to the atmosphere is primarily controlled by the vapor pressure of the relevant compounds within the plant tissue, which is in turn dependent on temperature as well as complex biochemical production processes. However, various natural and anthropogenic stressors can alter both the quantity and composition of the BVOCs emitted by plants. Many potential stressors are expected to become stronger as climate change effects escalate. The impacts of most stressors on BVOC emissions have not been well characterized, particularly in a field setting where changes in BVOC emissions could have influential feedbacks with climate. This study investigated the effects of two stressors on monoterpene and sesquiterpene emission rates at a field site in northern Michigan: acute ozone exposure and treatment with methyl jasmonate, an herbivory proxy. The study included six repetitions of the same experiment, each time using a new set of sub-canopy eastern white pine specimens. For each experiment, dynamic branch enclosures were simultaneously used on three specimens for sample collection: one ozone treatment tree, one methyl jasmonate treatment tree, and one control tree. Sampling lines were placed in each enclosure and VOCs were collected onto cartridges packed with Tenax GR adsorbent. Samples were collected several times per day for at least two days before treatment and for five days after treatment. Cartridges were analyzed via thermodesorption with an Agilent GC/MS/FID. This analysis allowed the identification and quantification of several monoterpene and sesquiterpene species in the samples

  16. The Influence of Volume, Temperature and Flow Rate on the of Separation Ru from IRC-50 Amberlite Resin

    International Nuclear Information System (INIS)

    Murdani Sumarsono; Djoko Widodo

    2002-01-01

    It was studied Ru elution of IRC-50 amberlite resin for separating, Ru of resin bonding. The resin bonding was ion exchange result of spent fuel uranyl nitrate. In this experiment, the eluent was used 6 N HNO 3 solution the adsorption of Ru was 20 ppm and then it was eluted with 6 N HNO 3 eluent. The objective of this experiment was to determine the operation condition of elution proses that was based on the value of Ru release from its bonding as much as possible. Based on the experiment, the relative good condition were resin volume = 205 ml, elution temperature = 85 o C and the flow rate of eluent = 2 ml 6 N HNO 3 / minute and Ru as result was 93 %. (author)

  17. Evaluation of two intracavitary high-dose-rate brachytherapy devices for irradiating additional and irregularly shaped volumes of breast tissue

    International Nuclear Information System (INIS)

    Lu, Sharon M.; Scanderbeg, Daniel J.; Barna, Patrick; Yashar, William; Yashar, Catheryn

    2012-01-01

    The SAVI and Contura breast brachytherapy applicators represent 2 recent advancements in brachytherapy technology that have expanded the number of women eligible for accelerated partial breast irradiation in the treatment of early-stage breast cancer. Early clinical experience with these 2 single-entry, multichannel high-dose-rate brachytherapy devices confirms their ease of use and dosimetric versatility. However, current clinical guidelines for SAVI and Contura brachytherapy may result in a smaller or less optimal volume of treated tissue compared with traditional interstitial brachytherapy. This study evaluates the feasibility of using the SAVI and Contura to irradiate larger and irregularly shaped target volumes, approaching what is treatable with the interstitial technique. To investigate whether additional tissue can be treated, 17 patients treated with the SAVI and 3 with the Contura were selected. For each patient, the planning target volume (PTV) was modified to extend 1.1 cm, 1.3 cm, and 1.5 cm beyond the tumor bed cavity. To evaluate dose conformance to an irregularly shaped target volume, 9 patients treated with the SAVI and 3 with the Contura were selected from the original 20 patients. The following asymmetric PTV margin combinations were assessed for each patient: 1.5/0.3, 1.3/0.3, and 1.1/0.3 cm. For all patients, treatment planning was performed, adopting the National Surgical Adjuvant Breast and Bowel Project guidelines, and dosimetric comparisons were made. The 6–1 and 8–1 SAVI devices can theoretically treat a maximal tissue margin of 1.5 cm and an asymmetric PTV with margins ranging from 0.3 to 1.5 cm. The 10–1 SAVI and Contura can treat a maximal margin of 1.3 cm and 1.1 cm, respectively, and asymmetric PTV with margins ranging from 0.3–1.3 cm. Compared with the Contura, the SAVI demonstrated greater dosimetric flexibility. Risk of developing excessive hot spots increased with the size of the SAVI device. Both the SAVI and Contura

  18. The application of positron emission tomography/computed tomography in radiation treatment planning: effect on gross target volume definition and treatment management.

    Science.gov (United States)

    Iğdem, S; Alço, G; Ercan, T; Unalan, B; Kara, B; Geceer, G; Akman, C; Zengin, F O; Atilla, S; Okkan, S

    2010-04-01

    To analyse the effect of the use of molecular imaging on gross target volume (GTV) definition and treatment management. Fifty patients with various solid tumours who underwent positron emission tomography (PET)/computed tomography (CT) simulation for radiotherapy planning from 2006 to 2008 were enrolled in this study. First, F-18 fluorodeoxyglucose (FDG)-PET and CT scans of the treatment site in the treatment position and then a whole body scan were carried out with a dedicated PET/CT scanner and fused thereafter. FDG-avid primary tumour and lymph nodes were included into the GTV. A multidisciplinary team defined the target volume, and contouring was carried out by a radiation oncologist using visual methods. To compare the PET/CT-based volumes with CT-based volumes, contours were drawn on CT-only data with the help of site-specific radiologists who were blind to the PET/CT results after a median time of 7 months. In general, our PET/CT volumes were larger than our CT-based volumes. This difference was significant in patients with head and neck cancers. Major changes (> or =25%) in GTV delineation were observed in 44% of patients. In 16% of cases, PET/CT detected incidental second primaries and metastatic disease, changing the treatment strategy from curative to palliative. Integrating functional imaging with FDG-PET/CT into the radiotherapy planning process resulted in major changes in a significant proportion of our patients. An interdisciplinary approach between imaging and radiation oncology departments is essential in defining the target volumes. Copyright 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  19. Comparison of five segmentation tools for 18F-fluoro-deoxy-glucose-positron emission tomography-based target volume definition in head and neck cancer.

    Science.gov (United States)

    Schinagl, Dominic A X; Vogel, Wouter V; Hoffmann, Aswin L; van Dalen, Jorn A; Oyen, Wim J; Kaanders, Johannes H A M

    2007-11-15

    Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with (18)F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may improve definition of the gross tumor volume (GTV). In this study, five methods for tumor delineation on FDG-PET are compared with CT-based delineation. Seventy-eight patients with Stages II-IV squamous cell carcinoma of the head and neck area underwent coregistered CT and FDG-PET. The primary tumor was delineated on CT, and five PET-based GTVs were obtained: visual interpretation, applying an isocontour of a standardized uptake value of 2.5, using a fixed threshold of 40% and 50% of the maximum signal intensity, and applying an adaptive threshold based on the signal-to-background ratio. Absolute GTV volumes were compared, and overlap analyses were performed. The GTV method of applying an isocontour of a standardized uptake value of 2.5 failed to provide successful delineation in 45% of cases. For the other PET delineation methods, volume and shape of the GTV were influenced heavily by the choice of segmentation tool. On average, all threshold-based PET-GTVs were smaller than on CT. Nevertheless, PET frequently detected significant tumor extension outside the GTV delineated on CT (15-34% of PET volume). The choice of segmentation tool for target-volume definition of head and neck cancer based on FDG-PET images is not trivial because it influences both volume and shape of the resulting GTV. With adequate delineation, PET may add significantly to CT- and physical examination-based GTV definition.

  20. Comparison of Five Segmentation Tools for 18F-Fluoro-Deoxy-Glucose-Positron Emission Tomography-Based Target Volume Definition in Head and Neck Cancer

    International Nuclear Information System (INIS)

    Schinagl, Dominic A.X.; Vogel, Wouter V.; Hoffmann, Aswin L.; Dalen, Jorn A. van; Oyen, Wim J.; Kaanders, Johannes H.A.M.

    2007-01-01

    Purpose: Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with 18 F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may improve definition of the gross tumor volume (GTV). In this study, five methods for tumor delineation on FDG-PET are compared with CT-based delineation. Methods and Materials: Seventy-eight patients with Stages II-IV squamous cell carcinoma of the head and neck area underwent coregistered CT and FDG-PET. The primary tumor was delineated on CT, and five PET-based GTVs were obtained: visual interpretation, applying an isocontour of a standardized uptake value of 2.5, using a fixed threshold of 40% and 50% of the maximum signal intensity, and applying an adaptive threshold based on the signal-to-background ratio. Absolute GTV volumes were compared, and overlap analyses were performed. Results: The GTV method of applying an isocontour of a standardized uptake value of 2.5 failed to provide successful delineation in 45% of cases. For the other PET delineation methods, volume and shape of the GTV were influenced heavily by the choice of segmentation tool. On average, all threshold-based PET-GTVs were smaller than on CT. Nevertheless, PET frequently detected significant tumor extension outside the GTV delineated on CT (15-34% of PET volume). Conclusions: The choice of segmentation tool for target-volume definition of head and neck cancer based on FDG-PET images is not trivial because it influences both volume and shape of the resulting GTV. With adequate delineation, PET may add significantly to CT- and physical examination-based GTV definition

  1. Observation of Repetition-Rate Dependent Emission From an Un-Gated Thermionic Cathode Rf Gun

    Energy Technology Data Exchange (ETDEWEB)

    Edelen, J. P.; Sun, Y.; Harris, J.R.; Lewellen, J.W.

    2017-06-02

    Recent work at Fermilab in collaboration with the Advanced Photon Source and members of other national labs, designed an experiment to study the relationship between the RF repetition rate and the average current per RF pulse. While existing models anticipate a direct relationship between these two parameters we observed an inverse relationship. We believe this is a result of damage to the barium coating on the cathode surface caused by a change in back-bombardment power that is unaccounted for in the existing theories. These observations shed new light on the challenges and fundamental limitations associated with scaling an ungated thermionic cathode RF gun to high average current.

  2. Differential controls by climate and physiology over the emission rates of biogenic volatile organic compounds from mature trees in a semi-arid pine forest.

    Science.gov (United States)

    Eller, Allyson S D; Young, Lindsay L; Trowbridge, Amy M; Monson, Russell K

    2016-02-01

    Drought has the potential to influence the emission of biogenic volatile organic compounds (BVOCs) from forests and thus affect the oxidative capacity of the atmosphere. Our understanding of these influences is limited, in part, by a lack of field observations on mature trees and the small number of BVOCs monitored. We studied 50- to 60-year-old Pinus ponderosa trees in a semi-arid forest that experience early summer drought followed by late-summer monsoon rains, and observed emissions for five BVOCs-monoterpenes, methylbutenol, methanol, acetaldehyde and acetone. We also constructed a throughfall-interception experiment to create "wetter" and "drier" plots. Generally, trees in drier plots exhibited reduced sap flow, photosynthesis, and stomatal conductances, while BVOC emission rates were unaffected by the artificial drought treatments. During the natural, early summer drought, a physiological threshold appeared to be crossed when photosynthesis ≅2 μmol m(-2) s(-1) and conductance ≅0.02 mol m(-2) s(-1). Below this threshold, BVOC emissions are correlated with leaf physiology (photosynthesis and conductance) while BVOC emissions are not correlated with other physicochemical factors (e.g., compound volatility and tissue BVOC concentration) that have been shown in past studies to influence emissions. The proportional loss of C to BVOC emission was highest during the drought primarily due to reduced CO2 assimilation. It appears that seasonal drought changes the relations among BVOC emissions, photosynthesis and conductance. When drought is relaxed, BVOC emission rates are explained mostly by seasonal temperature, but when seasonal drought is maximal, photosynthesis and conductance-the physiological processes which best explain BVOC emission rates-decline, possibly indicating a more direct role of physiology in controlling BVOC emission.

  3. Comparison of facility-level methane emission rates from natural gas production well pads in the Marcellus, Denver-Julesburg, and Uintah Basins

    Science.gov (United States)

    Omara, M.; Li, X.; Sullivan, M.; Subramanian, R.; Robinson, A. L.; Presto, A. A.

    2015-12-01

    The boom in shale natural gas (NG) production, brought about by advances in horizontal drilling and hydraulic fracturing, has yielded both economic benefits and concerns about environmental and climate impacts. In particular, leakages of methane from the NG supply chain could substantially increase the carbon footprint of NG, diminishing its potential role as a transition fuel between carbon intensive fossil fuels and renewable energy systems. Recent research has demonstrated significant variability in measured methane emission rates from NG production facilities within a given shale gas basin. This variability often reflect facility-specific differences in NG production capacity, facility age, utilization of emissions capture and control, and/or the level of facility inspection and maintenance. Across NG production basins, these differences in facility-level methane emission rates are likely amplified, especially if significant variability in NG composition and state emissions regulations are present. In this study, we measured methane emission rates from the NG production sector in the Marcellus Shale Basin (Pennsylvania and West Virginia), currently the largest NG production basin in the U.S., and contrast these results with those of the Denver-Julesburg (Colorado) and Uintah (Utah) shale basins. Facility-level methane emission rates were measured at 106 NG production facilities using the dual tracer flux (nitrous oxide and acetylene), Gaussian dispersion simulations, and the OTM 33A techniques. The distribution of facility-level average methane emission rate for each NG basin will be discussed, with emphasis on how variability in NG composition (i.e., ethane-to-methane ratios) and state emissions regulations impact measured methane leak rates. While the focus of this presentation will be on the comparison of methane leak rates among NG basins, the use of three complimentary top-down methane measurement techniques provides a unique opportunity to explore the

  4. A comparison between the order and the volume fill rates for a base-stock inventory control system under a compound renewal demand process

    OpenAIRE

    Larsen, Christian; Thorstenson, Anders

    2006-01-01

    The order fill rate is less commonly used than the volume fill rate (most often just denoted fill rate) as a performance measure for inventory control systems. However, in settings where the focus is on filling customer orders rather than total quantities, the order fill rate should be the preferred measure. In this paper we consider a continuous review, base-stock policy, where all replenishment orders have the same constant lead time and all unfilled demands are backordered. We develop exac...

  5. Environmental effects of energy production and utilization in the U. S. Volume 3. Techniques for controlling emissions

    Energy Technology Data Exchange (ETDEWEB)

    Newkirk, H.W. (comp.)

    1976-06-14

    Technological, social, economic and political techniques for controlling emission are summarized for environmental pollutants introduced into air, water and land resources. Chemical, radiological and physical factors are discussed. (PCS)

  6. The Blood Volume of the Guinea Pig: Effects of Epinephrine and Isoproterenol upon the Red Cell and Plasma Volumes, Heart Rate, and Mean Arterial Pressure,

    Science.gov (United States)

    1987-09-01

    capillaries (4), blood volumes calculated from plasma volume measures must correct for label that has left the system between the time of the injected dose...Splenic sequestration and contraction are mediated by the autonomic nervous system and blood-borne agents (10). Sympathetic nerve fibers from the truncus...sympathlcus and parasympathetic neurons of the nervus vagus (cranial nerve X) innervate the celiac plexus (8, 11). A subdivision of the celiac plexus

  7. Measures of star formation rates from infrared (Herschel) and UV (GALEX) emissions of galaxies in the HerMES fields

    Science.gov (United States)

    Buat, V.; Giovannoli, E.; Burgarella, D.; Altieri, B.; Amblard, A.; Arumugam, V.; Aussel, H.; Babbedge, T.; Blain, A.; Bock, J.; Boselli, A.; Castro-Rodríguez, N.; Cava, A.; Chanial, P.; Clements, D. L.; Conley, A.; Conversi, L.; Cooray, A.; Dowell, C. D.; Dwek, E.; Eales, S.; Elbaz, D.; Fox, M.; Franceschini, A.; Gear, W.; Glenn, J.; Griffin, M.; Halpern, M.; Hatziminaoglou, E.; Heinis, S.; Ibar, E.; Isaak, K.; Ivison, R. J.; Lagache, G.; Levenson, L.; Lonsdale, C. J.; Lu, N.; Madden, S.; Maffei, B.; Magdis, G.; Mainetti, G.; Marchetti, L.; Morrison, G. E.; Nguyen, H. T.; O'Halloran, B.; Oliver, S. J.; Omont, A.; Owen, F. N.; Page, M. J.; Pannella, M.; Panuzzo, P.; Papageorgiou, A.; Pearson, C. P.; Pérez-Fournon, I.; Pohlen, M.; Rigopoulou, D.; Rizzo, D.; Roseboom, I. G.; Rowan-Robinson, M.; Sánchez Portal, M.; Schulz, B.; Seymour, N.; Shupe, D. L.; Smith, A. J.; Stevens, J. A.; Strazzullo, V.; Symeonidis, M.; Trichas, M.; Tugwell, K. E.; Vaccari, M.; Valiante, E.; Valtchanov, I.; Vigroux, L.; Wang, L.; Ward, R.; Wright, G.; Xu, C. K.; Zemcov, M.

    2010-11-01

    The reliability of infrared (IR) and ultraviolet (UV) emissions to measure star formation rates (SFRs) in galaxies is investigated for a large sample of galaxies observed with the Spectral and Photometric Imaging Receiver (SPIRE) and the Photodetector Array Camera and Spectrometer (PACS) instruments on Herschel as part of the Herschel Multi-Tiered Extragalactic Survey (HerMES) project. We build flux-limited 250-μm samples of sources at redshift z 500 μm. Dust attenuation is discussed on the basis of commonly used diagnostics: the LIR/LUV ratio and the slope, β, of the UV continuum. A mean dust attenuation AUV of mag is measured in the samples. LIR/LUV is found to correlate with LIR. Galaxies with and 0.5 recipe commonly applied to local starbursts is found to overestimate the dust attenuation correction in our galaxy sample by a factor of ~2-3. The SFRs deduced from LIR are found to account for about 90 per cent of the total SFR; this percentage drops to 71 per cent for galaxies with (or ). For these faint objects, one needs to combine UV and IR emissions to obtain an accurate measure of the SFR.

  8. SCUSS u- BAND EMISSION AS A STAR-FORMATION-RATE INDICATOR

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhimin; Zhou, Xu; Wu, Hong; Fan, Zhou; Jiang, Zhao-Ji; Ma, Jun; Nie, Jun-Dan; Wang, Jia-Li; Wu, Zhen-Yu; Zhang, Tian-Meng; Zou, Hu [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China); Fan, Xiao-Hui; Lesser, Michael [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Jing, Yi-Peng [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Li, Cheng; Shen, Shi-Yin [Shanghai Astronomical Observatory, Chinese Academy of Science, 80 Nandan Road, Shanghai 200030 (China); Jiang, Lin-Hua, E-mail: zmzhou@bao.ac.cn [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)

    2017-01-20

    We present and analyze the possibility of using optical u- band luminosities to estimate star-formation rates (SFRs) of galaxies based on the data from the South Galactic Cap u band Sky Survey (SCUSS), which provides a deep u -band photometric survey covering about 5000 deg{sup 2} of the South Galactic Cap. Based on two samples of normal star-forming galaxies selected by the BPT diagram, we explore the correlations between u -band, H α , and IR luminosities by combing SCUSS data with the Sloan Digital Sky Survey and Wide-field Infrared Survey Explorer ( WISE ). The attenuation-corrected u -band luminosities are tightly correlated with the Balmer decrement-corrected H α luminosities with an rms scatter of ∼0.17 dex. The IR-corrected u luminosities are derived based on the correlations between the attenuation of u- band luminosities and WISE 12 (or 22) μ m luminosities, and then calibrated with the Balmer-corrected H α luminosities. The systematic residuals of these calibrations are tested against the physical properties over the ranges covered by our sample objects. We find that the best-fitting nonlinear relations are better than the linear ones and recommended to be applied in the measurement of SFRs. The systematic deviations mainly come from the pollution of old stellar population and the effect of dust extinction; therefore, a more detailed analysis is needed in future work.

  9. Summit CO2 emission rates by the CO2/SO2 ratio method at Kīlauea Volcano, Hawaiʻi, during a period of sustained inflation

    Science.gov (United States)

    Hager, S.A.; Gerlach, T.M.; Wallace, P.J.

    2008-01-01

    The emission rate of carbon dioxide escaping from the summit of Kīlauea Volcano, Hawaiʻi, proved highly variable, averaging 4900 ± 2000 metric tons per day (t/d) in June–July 2003 during a period of summit inflation. These results were obtained by combining over 90 measurements of COSPEC-derived SO2emission rates with synchronous CO2/SO2 ratios of the volcanic gas plume along the summit COSPEC traverse. The results are lower than the CO2 emission rate of 8500 ± 300 t/d measured by the same method in 1995–1999 during a period of long-term summit deflation [Gerlach, T.M., McGee, K.A., Elias, T., Sutton, A.J. and Doukas, M.P., 2002. Carbon dioxide emission rate of Kīlauea Volcano: Implications for primary magma and the summit reservoir. Journal of Geophysical Research-Solid Earth, 107(B9): art. no.-2189.]. Analysis of the data indicates that the emission rates of the present study likely reflect changes in the magma supply rate and residence time in the summit reservoir. It is also likely that emission rates during the inflation period were heavily influenced by SO2 pulses emitted adjacent to the COSPEC traverse, which biased CO2/SO2 ratios towards low values that may be unrepresentative of the global summit gas plume. We conclude that the SO2 pulses are consequences of summit re-inflation under way since 2003 and that CO2 emission rates remain comparable to, but more variable than, those measured prior to re-inflation.

  10. Increasing preload volume with water reduces rated appetite but not food intake in healthy men even with minimum delay between preload and test meal.

    Science.gov (United States)

    Gray, Richard W; French, Stephen J; Robinson, Tristan M; Yeomans, Martin R

    2003-02-01

    The role of gastric volume in the short-term control of eating in humans remains unclear, with some studies reporting that food volume alone can reduce appetite but others finding no such effect. A recent study in our laboratory, found effects of preload volume on subjective appetite (hunger, fullness) but not intake, and found effects of preload energy on intake but not appetite. That study used an interval of 30 min between serving preloads and the test meal, and the present study attempted to maximise the effects of the volume manipulation by removing the delay between the preload and test meal. We administered four soup-based preloads varying in volume (150 and 450 ml) using water, and energy density (1.4 and 4.2 kJ/ml) using maltodextrin, producing three energy levels (209, 629, 629 and 1886 kJ; repeated measures). These were followed immediately by an unlimited hot pasta lunch, during which food weight was monitored continuously by computer. Increasing soup volume at constant energy (629 kJ) reduced appetite ratings, but not intake. In contrast, increasing soup energy at constant volume (450 ml) reduced intake, without affecting appetite. The discrepancies between our results and other reported studies suggest that volume is more influential when intakes are large, or that there may be a threshold concentration for nutrients in the GI tract before volume alone is tangibly expressed in subsequent eating.

  11. Postoperative HDR afterloading brachytherapy: Vaginal tumor recurrence rates in patients with endometrial carcinoma dependent on treatment volumes

    International Nuclear Information System (INIS)

    Kloetzer, K.H.; Guenther, R.; Wendt, T.

    1997-01-01

    Patients and Method: At Jena University, Department of Radiotherapy, from 1981 to 1990 108 patients with endometrical carcinoma were postoperatively treated with high dose radiation brachytherapy of the vagina without additional percutaneous radiotherapy. Histology showed more or less differenciated adenocarcinoma in 90% of all patients, all patients were postoperatively stage I or II without proven lymphatic metastases. Dependent on individual figures patients were distributed to 3 different gorups: group A: 4 x 10 Gy, tissue-thickness of 1 cm (vaginal apex) respectively 0.5 cm (lower vaginal walls); group B: 4 x 10 Gy, tissue thickness of 1 cm (upper vaginal wall); group C: 4 x 10 Gy, tissue-thickness of 0.5 cm (both excluding the lower vaginal walls). Results: Both 3-year survival rates (group A: 96.6%, group B: 96.9%, group C: 97.7%) and tumor relapse rates of the vaginal apex (group A: 0, group B: 3.1%, group C: 2.2%) don't show significant differences. No case of local tumor recurrence was seen in the upper 2/3 of the vagina and the pelvic walls. Late side effects concerning bladder and rectum (grade III to IV, EORTC/RTOG) could be minimized by reducing the treatment volume (group A: 6.8%/12.6%, group B: 6,2%/3.1%, group C: 2.2%/0). (orig./AJ) [de

  12. Impact of 18-fluorodeoxyglucose positron emission tomography on computed tomography defined target volumes in radiation treatment planning of esophageal cancer : reduction in geographic misses with equal inter-observer variability

    NARCIS (Netherlands)

    Schreurs, Liesbeth; Busz, D. M.; Paardekooper, G. M. R. M.; Beukema, J. C.; Jager, P. L.; Van der Jagt, E. J.; van Dam, G. M.; Groen, H.; Plukker, J. Th. M.; Langendijk, J. A.

    P>Target volume definition in modern radiotherapy is based on planning computed tomography (CT). So far, 18-fluorodeoxyglucose positron emission tomography (FDG-PET) has not been included in planning modality in volume definition of esophageal cancer. This study evaluates fusion of FDG-PET and CT in

  13. Bioenergy. Data base for the statistics of the renewable energy and emissions balance. Material volume; Bioenergie. Datengrundlagen fuer die Statistik der erneuerbaren Energien und Emissionsbilanzierung. Materialband

    Energy Technology Data Exchange (ETDEWEB)

    Dreher, Marion; Memmler, Michael; Rother, Stefan; Schneider, Sven [Umweltbundesamt, Dessau (Germany); Boehme, Dieter [Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Berlin (Germany)

    2012-02-15

    In July 2011, the Federal Environment Agency (Dessau-Rosslau, Federal Republic of Germany) and the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (Berlin, Federal Republic of Germany) performed the workshop ''Bioenergy. Data base for the statistics of the renewable energy and emissions balance''. The material volume of this workshop under consideration contains plenary lectures on the state of knowledge and information need as well as materials to the working groups solid biomass (working group 1), biogas (working group 2) and liquid biomass (working group 3).

  14. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Research Team . Volume 2; Appendices

    Science.gov (United States)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage (horizontal and vertical tail). This report contains the Appendices to Volume I.

  15. Evaluation of stone volume distribution in renal collecting system as a predictor of stone-free rate after percutaneous nephrolithotomy: a retrospective single-center study.

    Science.gov (United States)

    Atalay, Hasan Anıl; Canat, Lutfi; Bayraktarlı, Recep; Alkan, Ilter; Can, Osman; Altunrende, Fatih

    2017-06-23

    We analyzed our stone-free rates of PNL with regard to stone burden and its ratio to the renal collecting system volume. Data of 164 patients who underwent PNL were analyzed retrospectively. Volume segmentation of renal collecting system and stones were done using 3D segmentation software with the images obtained from CT data. Analyzed stone volume (ASV) and renal collecting system volume (RCSV) were measured and the ASV-to-RCSV ratio was calculated after the creation of a 3D surface volume rendering of renal stones and the collecting system. Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free rates; also we assessed the predictive accuracy of the ASV-to-RCSV ratio using the receiving operating curve (ROC) and AUC. The stone-free rate of PNL monotherapy was 53% (164 procedures).The ASV-to-RCSV ratio and calyx number with stones were the most influential predictors of stone-free status (OR 4.15, 95% CI 2.24-7.24, renal collecting system, which is calculated using the 3D volume segmentation method, is a significant determinant of the stone-free rate before PCNL surgery. It could be used as a single guide variable by the clinician before renal stone surgery to predict extra requirements for stone clearance.

  16. Understanding the relationship between the Centers for Medicare and Medicaid Services' Hospital Compare star rating, surgical case volume, and short-term outcomes after major cancer surgery.

    Science.gov (United States)

    Kaye, Deborah R; Norton, Edward C; Ellimoottil, Chad; Ye, Zaojun; Dupree, James M; Herrel, Lindsey A; Miller, David C

    2017-11-01

    Both the Centers for Medicare and Medicaid Services' (CMS) Hospital Compare star rating and surgical case volume have been publicized as metrics that can help patients to identify high-quality hospitals for complex care such as cancer surgery. The current study evaluates the relationship between the CMS' star rating, surgical volume, and short-term outcomes after major cancer surgery. National Medicare data were used to evaluate the relationship between hospital star ratings and cancer surgery volume quintiles. Then, multilevel logistic regression models were fit to examine the association between cancer surgery outcomes and both star rankings and surgical volumes. Lastly, a graphical approach was used to compare how well star ratings and surgical volume predicted cancer surgery outcomes. This study identified 365,752 patients undergoing major cancer surgery for 1 of 9 cancer types at 2,550 hospitals. Star rating was not associated with surgical volume (P cancer surgery outcomes (mortality, complication rate, readmissions, and prolonged length of stay). The adjusted predicted probabilities for 5- and 1-star hospitals were 2.3% and 4.5% for mortality, 39% and 48% for complications, 10% and 15% for readmissions, and 8% and 16% for a prolonged length of stay, respectively. The adjusted predicted probabilities for hospitals with the highest and lowest quintile cancer surgery volumes were 2.7% and 5.8% for mortality, 41% and 55% for complications, 12.2% and 11.6% for readmissions, and 9.4% and 13% for a prolonged length of stay, respectively. Furthermore, surgical volume and the star rating were similarly associated with mortality and complications, whereas the star rating was more highly associated with readmissions and prolonged length of stay. In the absence of other information, these findings suggest that the star rating may be useful to patients when they are selecting a hospital for major cancer surgery. However, more research is needed before these ratings can

  17. Mass-ablation-rate measurements in direct-drive cryogenic implosions using x-ray self-emission images

    Energy Technology Data Exchange (ETDEWEB)

    Davis, A. K., E-mail: adavi@lle.rochester.edu; Michel, D. T.; Hu, S. X.; Craxton, R. S.; Epstein, R.; Goncharov, V. N.; Igumenshchev, I. V.; Sangster, T. C.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14636 (United States)

    2014-11-15

    A technique to measure the mass ablation rate in direct-drive inertial confinement fusion implosions using a pinhole x-ray framing camera is presented. In target designs consisting of two layers of different materials, two x-ray self-emission peaks from the coronal plasma were measured once the laser burned through the higher-Z outer layer. The location of the inner peak is related to the position of the ablation front and the location of the outer peak corresponds to the position of the interface of the two layers in the plasma. The emergence of the second peak was used to measure the burnthrough time of the outer layer, giving the average mass ablation rate of the material and instantaneous mass remaining. By varying the thickness of the outer layer, the mass ablation rate can be obtained as a function of time. Simulations were used to validate the methods and verify that the measurement techniques are not sensitive to perturbation growth at the ablation surface.

  18. Effects of phosphorus availability and genetic variation of leaf terpene content and emission rate in Pinus pinaster seedlings susceptible and resistant to the pine weevil, Hylobius abietis.

    Science.gov (United States)

    Blanch, J-S; Sampedro, L; Llusià, J; Moreira, X; Zas, R; Peñuelas, J

    2012-03-01

    We studied the effects of phosphorus fertilisation on foliar terpene concentrations and foliar volatile terpene emission rates in six half-sib families of Pinus pinaster Ait. seedlings. Half of the seedlings were resistant to attack of the pine weevil Hylobius abietis L., a generalist phloem feeder, and the remaining seedlings were susceptible to this insect. We hypothesised that P stress could modify the terpene concentration in the needles and thus lead to altered terpene emission patterns relevant to plant-insect signalling. The total concentration and emission rate ranged between 5732 and 13,995 μg·g(-1) DW and between 2 and 22 μg·g(-1) DW·h(-1), respectively. Storage and emission were dominated by the isomers α- and β-pinene (77.2% and 84.2% of the total terpene amount amassed and released, respectively). In both resistant and susceptible families, P stress caused an increase of 31% in foliar terpene concentration with an associated 5-fold decrease in terpene emission rates. A higher terpene content in the leaves implies that the 'excess carbon', available under limiting growth conditions (P scarcity), is allocated to terpene production. Sensitive families showed a greater increase in terpene emission rates with increasing P concentrations, which could explain their susceptibility to H. abietis. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  19. Whole-tumor histogram analysis of the cerebral blood volume map: tumor volume defined by 11C-methionine positron emission tomography image improves the diagnostic accuracy of cerebral glioma grading.

    Science.gov (United States)

    Wu, Rongli; Watanabe, Yoshiyuki; Arisawa, Atsuko; Takahashi, Hiroto; Tanaka, Hisashi; Fujimoto, Yasunori; Watabe, Tadashi; Isohashi, Kayako; Hatazawa, Jun; Tomiyama, Noriyuki

    2017-10-01

    This study aimed to compare the tumor volume definition using conventional magnetic resonance (MR) and 11C-methionine positron emission tomography (MET/PET) images in the differentiation of the pre-operative glioma grade by using whole-tumor histogram analysis of normalized cerebral blood volume (nCBV) maps. Thirty-four patients with histopathologically proven primary brain low-grade gliomas (n = 15) and high-grade gliomas (n = 19) underwent pre-operative or pre-biopsy MET/PET, fluid-attenuated inversion recovery, dynamic susceptibility contrast perfusion-weighted magnetic resonance imaging, and contrast-enhanced T1-weighted at 3.0 T. The histogram distribution derived from the nCBV maps was obtained by co-registering the whole tumor volume delineated on conventional MR or MET/PET images, and eight histogram parameters were assessed. The mean nCBV value had the highest AUC value (0.906) based on MET/PET images. Diagnostic accuracy significantly improved when the tumor volume was measured from MET/PET images compared with conventional MR images for the parameters of mean, 50th, and 75th percentile nCBV value (p = 0.0246, 0.0223, and 0.0150, respectively). Whole-tumor histogram analysis of CBV map provides more valuable histogram parameters and increases diagnostic accuracy in the differentiation of pre-operative cerebral gliomas when the tumor volume is derived from MET/PET images.

  20. Effect of age on heart rate, blood lactate concentration, packed cell volume and hemoglobin to exercise in Jeju crossbreed horses

    Directory of Open Access Journals (Sweden)

    Ok-Deuk Kang

    2017-01-01

    Full Text Available Abstract Background This study aimed to analyze the on heart rate, blood lactate concentration, packed cell volume (PCV and hemoglobin (Hb response after conducting exercise in endurance horses. Methods A total of 20 healthy 3–9-years-old Jeju crossbreed mares (5.95 ± 2.24 year of age and 312.65 ± 13.59 kg of weight currently participating the endurance competition were used. The field tests selected for the experiment was gallop (approximately 8.3 m/s along the selected 2.5 km course (a natural forest trail, not artificial road; a closed loop course. The horses were divided into three groups according to their age; 3–4 years of age (G1, 3.29 ± 0.49 year, 6–7 years of age (G2, 6.42 ± 0.53, and 8–9 years of age (G3, 8.50 ± 0.55. The measurements times for the heart rate, blood lactate concentration, PCV, and Hb analysis were conducted before exercise (T0, shortly after exercise (T1, 15 min after exercise (T2, and 30 min after exercise (T3, respectively. Data was analyzed using an analysis of covariance (ANCOVA for repeated measures with times and groups. Results The results of the comparison depending on the passage of rest time after exercise suggest that the heart rate and blood lactate concentration of three groups at T2 significantly decreased compared to T1 (p < 0.001. PCV of the G2 and G3 groups were significantly decreased at T2 compared to T1 (p < 0.01. Hb values at G2 (p < 0.01 and G3 (p < 0.001 groups were significantly decreased at T2 as compared to T1. However, heart rate, blood lactate concentration, PCV and Hb level at T1 showed no difference in the comparison of horses from different age groups with the exception of G3 group in terms of heart rate. Conclusion The physiologic and hematological responses of horses during recovery time after 2,500 m exercise with gallop were no significant difference among the groups. These data are useful as a response evaluation method for

  1. 0-6629 : Texas specific drive cycles and idle emissions rates for using with EPA's MOVES model, [project summary].

    Science.gov (United States)

    2013-08-01

    The U.S. Environmental Protection Agencys : newest emissions model, Motor Vehicle Emission : Simulator (MOVES), enables users to use local : drive schedules(representative vehicle speed : profiles) in order to perform an accurate analysis : of emi...

  2. Texas-specific drive cycles and idle emissions rates for using with EPA's MOVES model : final report.

    Science.gov (United States)

    2014-05-01

    The U.S. Environmental Protection Agencys (EPA) newest emissions model, MOtor Vehicle : Emission Simulator (MOVES), uses a disaggregate approach that enables the users of the model to create : and use local drive schedules (drive cycles) in order ...

  3. THE DETECTION RATE OF EARLY UV EMISSION FROM SUPERNOVAE: A DEDICATED GALEX/PTF SURVEY AND CALIBRATED THEORETICAL ESTIMATES

    Energy Technology Data Exchange (ETDEWEB)

    Ganot, Noam; Gal-Yam, Avishay; Ofek, Eran O.; Sagiv, Ilan; Waxman, Eli; Lapid, Ofer [Department of Particle Physics and Astrophysics, Faculty of Physics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Kulkarni, Shrinivas R.; Kasliwal, Mansi M. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Ben-Ami, Sagi [Smithsonian Astrophysical Observatory, Harvard-Smithsonian Ctr. for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chelouche, Doron; Rafter, Stephen [Physics Department, Faculty of Natural Sciences, University of Haifa, 31905 Haifa (Israel); Behar, Ehud; Laor, Ari [Physics Department, Technion Israel Institute of Technology, 32000 Haifa (Israel); Poznanski, Dovi; Nakar, Ehud; Maoz, Dan [School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel); Trakhtenbrot, Benny [Institute for Astronomy, ETH Zurich, Wolfgang-Pauli-Strasse 27 Zurich 8093 (Switzerland); Neill, James D.; Barlow, Thomas A.; Martin, Christofer D., E-mail: noam.ganot@gmail.com [California Institute of Technology, 1200 East California Boulevard, MC 278-17, Pasadena, CA 91125 (United States); Collaboration: ULTRASAT Science Team; WTTH consortium; GALEX Science Team; Palomar Transient Factory; and others

    2016-03-20

    The radius and surface composition of an exploding massive star, as well as the explosion energy per unit mass, can be measured using early UV observations of core-collapse supernovae (SNe). We present the first results from a simultaneous GALEX/PTF search for early ultraviolet (UV) emission from SNe. Six SNe II and one Type II superluminous SN (SLSN-II) are clearly detected in the GALEX near-UV (NUV) data. We compare our detection rate with theoretical estimates based on early, shock-cooling UV light curves calculated from models that fit existing Swift and GALEX observations well, combined with volumetric SN rates. We find that our observations are in good agreement with calculated rates assuming that red supergiants (RSGs) explode with fiducial radii of 500 R{sub ⊙}, explosion energies of 10{sup 51} erg, and ejecta masses of 10 M{sub ⊙}. Exploding blue supergiants and Wolf–Rayet stars are poorly constrained. We describe how such observations can be used to derive the progenitor radius, surface composition, and explosion energy per unit mass of such SN events, and we demonstrate why UV observations are critical for such measurements. We use the fiducial RSG parameters to estimate the detection rate of SNe during the shock-cooling phase (<1 day after explosion) for several ground-based surveys (PTF, ZTF, and LSST). We show that the proposed wide-field UV explorer ULTRASAT mission is expected to find >85 SNe per year (∼0.5 SN per deg{sup 2}), independent of host galaxy extinction, down to an NUV detection limit of 21.5 mag AB. Our pilot GALEX/PTF project thus convincingly demonstrates that a dedicated, systematic SN survey at the NUV band is a compelling method to study how massive stars end their life.

  4. Stimulus rate dependence of regional cerebral blood flow in human striate cortex, demonstrated by positron emission tomography

    International Nuclear Information System (INIS)

    Fox, P.T.; Raichle, M.E.

    1984-01-01

    The purpose of this investigation was to determine the relationship between the repetition rate of a simple sensory stimulus and regional cerebral blood flow (rCBF) in the human brain. Positron emission tomography (PET), using intravenously administered H 2 ( 15 )O as the diffusible blood-flow tracer, was employed for all CBF measurements. The use of H 2 ( 15 )O with PET allowed eight CBF measurements to be made in rapid sequence under multiple stimulation conditions without removing the subject from the tomograph. Nine normal volunteers each underwent a series of eight H2( 15 )O PET measurements of CBF. Initial and final scans were made during visual deprivation. The six intervening scans were made during visual activation with patterned-flash stimuli given in random order at 1.0-, 3.9-, 7.8-, 15.5-, 33.1-, and 61-Hz repetition rates. The region of greatest rCBF increase was determined. Within this region the rCBF was determined for every test condition and then expressed as the percentage change from the value of the initial unstimulated scan (rCBF% delta). In every subject, striate cortex rCBF% delta varied systematically with stimulus rate. Between 0 and 7.8 Hz, rCBF% delta was a linear function of stimulus repetition rate. The rCBF response peaked at 7.8 Hz and then declined. The rCBF% delta during visual stimulation was significantly greater than that during visual deprivation for every stimulus rate except 1.0 Hz. The anatomical localization of the region of peak rCBF response was determined for every subject to be the mesial occipital lobes along the calcarine fissure, primary visual cortex. Stimulus rate is a significant determinant of rCBF response in the visual cortex. Investigators of brain responses to selective activation procedures should be aware of the potential effects of stimulus rate on rCBF and other measurements of cerebral metabolism

  5. Does Size Really Matter? Analysis of the Effect of Large Fibroids and Uterine Volumes on Complication Rates of Uterine Artery Embolisation

    International Nuclear Information System (INIS)

    Parthipun, A. A.; Taylor, J.; Manyonda, I.; Belli, A. M.

    2010-01-01

    The purpose of this study was to determine whether there is a correlation between large uterine fibroid diameter, uterine volume, number of vials of embolic agent used and risk of complications from uterine artery embolisation (UAE). This was a prospective study involving 121 patients undergoing UAE embolisation for symptomatic uterine fibroids at a single institution. Patients were grouped according to diameter of largest fibroid and uterine volume. Results were also stratified according to the number of vials of embolic agent used and rate of complications. No statistical difference in complication rate was demonstrated between the two groups according to diameter of the largest fibroid (large fibroids were classified as ≥10 cm; Fisher's exact test P = 1.00), and no statistical difference in complication rate was demonstrated according to uterine volume (large uterine volume was defined as ≥750 cm 3 ; Fisher's exact test P = 0.70). 84 of the 121 patients had documentation of the number of vials used during the procedure. Patients were divided into two groups, with ≥4 used defined as a large number of embolic agent. There was no statistical difference between these two groups and no associated increased risk of developing complications. This study showed no increased incidence of complications in women with large-diameter fibroids or uterine volumes as defined. In addition, there was no evidence of increased complications according to quantity of embolic material used. Therefore, UAE should be offered to women with large fibroids and uterine volumes.

  6. Improved optical flow velocity analysis in SO2 camera images of volcanic plumes - implications for emission-rate retrievals investigated at Mt Etna, Italy and Guallatiri, Chile

    Science.gov (United States)

    Gliß, Jonas; Stebel, Kerstin; Kylling, Arve; Sudbø, Aasmund

    2018-02-01

    Accurate gas velocity measurements in emission plumes are highly desirable for various atmospheric remote sensing applications. The imaging technique of UV SO2 cameras is commonly used to monitor SO2 emissions from volcanoes and anthropogenic sources (e.g. power plants, ships). The camera systems capture the emission plumes at high spatial and temporal resolution. This allows the gas velocities in the plume to be retrieved directly from the images. The latter can be measured at a pixel level using optical flow (OF) algorithms. This is particularly advantageous under turbulent plume conditions. However, OF algorithms intrinsically rely on contrast in the images and often fail to detect motion in low-contrast image areas. We present a new method to identify ill-constrained OF motion vectors and replace them using the local average velocity vector. The latter is derived based on histograms of the retrieved OF motion fields. The new method is applied to two example data sets recorded at Mt Etna (Italy) and Guallatiri (Chile). We show that in many cases, the uncorrected OF yields significantly underestimated SO2 emission rates. We further show that our proposed correction can account for this and that it significantly improves the reliability of optical-flow-based gas velocity retrievals. In the case of Mt Etna, the SO2 emissions of the north-eastern crater are investigated. The corrected SO2 emission rates range between 4.8 and 10.7 kg s-1 (average of 7.1 ± 1.3 kg s-1) and are in good agreement with previously reported values. For the Guallatiri data, the emissions of the central crater and a fumarolic field are investigated. The retrieved SO2 emission rates are between 0.5 and 2.9 kg s-1 (average of 1.3 ± 0.5 kg s-1) and provide the first report of SO2 emissions from this remotely located and inaccessible volcano.

  7. A stock-flow consistent input-output model with applications to energy price shocks, interest rates, and heat emissions

    Science.gov (United States)

    Berg, Matthew; Hartley, Brian; Richters, Oliver

    2015-01-01

    By synthesizing stock-flow consistent models, input-output models, and aspects of ecological macroeconomics, a method is developed to simultaneously model monetary flows through the financial system, flows of produced goods and services through the real economy, and flows of physical materials through the natural environment. This paper highlights the linkages between the physical environment and the economic system by emphasizing the role of the energy industry. A conceptual model is developed in general form with an arbitrary number of sectors, while emphasizing connections with the agent-based, econophysics, and complexity economics literature. First, we use the model to challenge claims that 0% interest rates are a necessary condition for a stationary economy and conduct a stability analysis within the parameter space of interest rates and consumption parameters of an economy in stock-flow equilibrium. Second, we analyze the role of energy price shocks in contributing to recessions, incorporating several propagation and amplification mechanisms. Third, implied heat emissions from energy conversion and the effect of anthropogenic heat flux on climate change are considered in light of a minimal single-layer atmosphere climate model, although the model is only implicitly, not explicitly, linked to the economic model.

  8. Absolute disintegration rate and 320 keV {gamma}-ray emission probability of {sup 51}Cr

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, M.C.M. de [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes /Instituto de Radioprotecao e Dosimetria (LNMRI/ IRD), Avenida Salvador Allende, s/no. Recreio-Rio de Janeiro, CEP 22780-160 (Brazil)], E-mail: candida@ird.gov.br; Iwahara, A.; Poledna, R.; Silva, C.J. da; Delgado, J.U. [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes /Instituto de Radioprotecao e Dosimetria (LNMRI/ IRD), Avenida Salvador Allende, s/no. Recreio-Rio de Janeiro, CEP 22780-160 (Brazil)

    2007-09-21

    This work describes the procedures for determining absolutely the {sup 51}Cr disintegration rate by using the 4{pi}{beta}-{gamma} coincidence and anti-coincidence counting and the sum-peak methods. A 4''x4''-NaI(Tl) scintillation detector was used in the {gamma}- channel of the 4{pi}{beta}-{gamma} coincidence system for {gamma}-ray counting. In the {beta}-channel, a 4{pi} gas flow proportional counter was used for counting of characteristic X-rays and Auger electrons originating from the electron capture events of the {sup 51}Cr decay scheme. Gamma spectrometry measurements by high-pure planar and coaxial germanium detectors were performed in the sum-peak method and in the determination of the 320 keV {gamma}-emission probability of {sup 51}Cr. This latter determined value agrees with the recent values found in the literature, confirming the reliability of the three methods used in this work for the disintegration rate measurements.

  9. CHARACTERIZATION OF MERCURY EMISSIONS AT A CHLOR-ALKALI PLANT, VOLUME I. REPORT AND APPENDICES A-E

    Science.gov (United States)

    The report gives results of a characterization of mercury (Hg) emissions at a chlor-alkali plant. Up to 160 short tons (146 Mg) of Hg is consumed by the chlor-alkali industry each year. Very little quantitative information is currently available however, on the actual Hg losses f...

  10. Fracto-mechanoluminescent light emission of EuD4TEA-PDMS composites subjected to high strain-rate compressive loading

    Science.gov (United States)

    Ryu, Donghyeon; Castaño, Nicolas; Bhakta, Raj; Kimberley, Jamie

    2017-08-01

    The objective of this study is to understand light emission characteristics of fracto-mechanoluminescent (FML) europium tetrakis(dibenzoylmethide)-triethylammonium (EuD4TEA) crystals under high strain-rate compressive loading. As a sensing material that can play a pivotal role for the self-powered impact sensor technology, it is important to understand transformative light emission characteristics of the FML EuD4TEA crystals under high strain-rate compressive loading. First, EuD4TEA crystals were synthesized and embedded into polydimethylsiloxane (PDMS) elastomer to fabricate EuD4TEA-PDMS composite test specimens. Second, the prepared EuD4TEA-PDMS composites were tested using the modified Kolsky bar setup equipped with a high-speed camera. Third, FML light emission was captured to yield 12 bit grayscale video footage, which was processed to quantify the FML light emission. Finally, quantitative parameters were generated by taking into account pixel values and population of pixels of the 12 bit grayscale images to represent FML light intensity. The FML light intensity was correlated with high strain-rate compressive strain and strain rate to understand the FML light emission characteristics under high strain-rate compressive loading that can result from impact occurrences.

  11. Evaluation of left ventricular function and volume in patients with dilated cardiomyopathy: Gated myocardial single-photon emission tomography (SPECT) versus echocardiography

    International Nuclear Information System (INIS)

    Berk, Fatma; Isgoren, S.; Demir, H.; Kozdag, G.; Ural, D.; Komsuoglu, B.

    2005-01-01

    Left ventricular function, volumes and regional wall motion provide valuable diagnostic information and are of long-term prognostic importance in patients with dilated cardiomyopathy (DCM). This study was designed to compare the effectiveness of 2D-echocardiography and gated single-photon emission tomography (SPECT) for evaluation of these parameters in patients with DCM. Gated SPECT and 2D-echocardiography were performed in 33 patients having DCM. Gated SPECT data, including left ventricular ejection fraction (LVEF), were processed using an automated algorithm. Standard technique was used for 2D-echocardiography. Regional wall motion was evaluated using both modalities and was scored by two independent observers using a 16-sement model with a 5-point scoring system. The overall agreement between the two imaging modalities for the assessment of regional wall motion was 56% (298/528 segments). With gated SPECT, LEVF, end-diastolic volume (EDV), and end-diastolic volume (EDV), and end-systolic volume (ESV) were 27+-9%, 217+-73mL, respectively, and 30.8%, 195+-58mL and, 137+-48 mL with echocardiography. The correlation between gated SPECT and 2-D-echocardiography was good (r=0.76, P<0.01) for the assessment of LVEF. The correlation for EDV and ESV were also good, but with wider limits of agreement (r=0.72, P<0.01 and r=0.73, P<0.01, respectively) and significantly higher values were obtained with gated SPECT (P<0.01). Gated SPECT and 2D-echocardiography correlate well for the assessment of LV function and LV volumes. Like 2D-echocardiography, gated SPECT provides reliable information about LV function and dimension with the additional advantage of perfusion data. (author)

  12. Intra-tumour 18F-FDG uptake heterogeneity decreases the reliability on target volume definition with positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Dong, Xinzhe; Wu, Peipei; Sun, Xiaorong; Li, Wenwu; Wan, Honglin; Yu, Jinming; Xing, Ligang

    2015-06-01

    This study aims to explore whether the intra-tumour (18) F-fluorodeoxyglucose (FDG) uptake heterogeneity affects the reliability of target volume definition with FDG positron emission tomography/computed tomography (PET/CT) imaging for nonsmall cell lung cancer (NSCLC) and squamous cell oesophageal cancer (SCEC). Patients with NSCLC (n = 50) or SCEC (n = 50) who received (18)F-FDG PET/CT scanning before treatments were included in this retrospective study. Intra-tumour FDG uptake heterogeneity was assessed by visual scoring, the coefficient of variation (COV) of the standardised uptake value (SUV) and the image texture feature (entropy). Tumour volumes (gross tumour volume (GTV)) were delineated on the CT images (GTV(CT)), the fused PET/CT images (GTV(PET-CT)) and the PET images, using a threshold at 40% SUV(max) (GTV(PET40%)) or the SUV cut-off value of 2.5 (GTV(PET2.5)). The correlation between the FDG uptake heterogeneity parameters and the differences in tumour volumes among GTV(CT), GTV(PET-CT), GTV(PET40%) and GTV(PET2.5) was analysed. For both NSCLC and SCEC, obvious correlations were found between uptake heterogeneity, SUV or tumour volumes. Three types of heterogeneity parameters were consistent and closely related to each other. Substantial differences between the four methods of GTV definition were found. The differences between the GTV correlated significantly with PET heterogeneity defined with the visual score, the COV or the textural feature-entropy for NSCLC and SCEC. In tumours with a high FDG uptake heterogeneity, a larger GTV delineation difference was found. Advance image segmentation algorithms dealing with tracer uptake heterogeneity should be incorporated into the treatment planning system. © 2015 The Royal Australian and New Zealand College of Radiologists.

  13. Intra-tumour 18F-FDG uptake heterogeneity decreases the reliability on target volume definition with positron emission tomography/computed tomography imaging

    International Nuclear Information System (INIS)

    Dong, Xinzhe; Wu, Peipei; Yu, Jinming; Xing, Ligang; Sun, Xiaorong; Li, Wenwu; Wan, Honglin

    2015-01-01

    This study aims to explore whether the intra-tumour 18 F-fluorodeoxyglucose (FDG) uptake heterogeneity affects the reliability of target volume definition with FDG positron emission tomography/computed tomography (PET/CT) imaging for nonsmall cell lung cancer (NSCLC) and squamous cell oesophageal cancer (SCEC). Patients with NSCLC (n = 50) or SCEC (n = 50) who received 18 F-FDG PET/CT scanning before treatments were included in this retrospective study. Intra-tumour FDG uptake heterogeneity was assessed by visual scoring, the coefficient of variation (COV) of the standardised uptake value (SUV) and the image texture feature (entropy). Tumour volumes (gross tumour volume (GTV) ) were delineated on the CT images (GTV CT ), the fused PET/CT images (GTV PET-CT ) and the PET images, using a threshold at 40% SUV max (GTV PET40% ) or the SUV cut-off value of 2.5 (GTV PET2.5 ). The correlation between the FDG uptake heterogeneity parameters and the differences in tumour volumes among GTV CT , GTV PET-CT , GTV PET40% and GTV PET2.5 was analysed. For both NSCLC and SCEC, obvious correlations were found between uptake heterogeneity, SUV or tumour volumes. Three types of heterogeneity parameters were consistent and closely related to each other. Substantial differences between the four methods of GTV definition were found. The differences between the GTV correlated significantly with PET heterogeneity defined with the visual score, the COV or the textural feature-entropy for NSCLC and SCEC. In tumours with a high FDG uptake heterogeneity, a larger GTV delineation difference was found. Advance image segmentation algorithms dealing with tracer uptake heterogeneity should be incorporated into the treatment planning system.

  14. Resistance training intensity and volume affect changes in rate of force development in resistance-trained men.

    Science.gov (United States)

    Mangine, Gerald T; Hoffman, Jay R; Wang, Ran; Gonzalez, Adam M; Townsend, Jeremy R; Wells, Adam J; Jajtner, Adam R; Beyer, Kyle S; Boone, Carleigh H; Miramonti, Amelia A; LaMonica, Michael B; Fukuda, David H; Ratamess, Nicholas A; Stout, Jeffrey R

    2016-12-01

    To compare the effects of two different resistance training programs, high intensity (INT) and high volume (VOL), on changes in isometric force (FRC), rate of force development (RFD), and barbell velocity during dynamic strength testing. Twenty-nine resistance-trained men were randomly assigned to either the INT (n = 15, 3-5 RM, 3-min rest interval) or VOL (n = 14, 10-12 RM, 1-min rest interval) training group for 8 weeks. All participants completed a 2-week preparatory phase prior to randomization. Measures of barbell velocity, FRC, and RFD were performed before (PRE) and following (POST) the 8-week training program. Barbell velocity was determined during one-repetition maximum (1RM) testing of the squat (SQ) and bench press (BP) exercises. The isometric mid-thigh pull was used to assess FRC and RFD at specific time bands ranging from 0 to 30, 50, 90, 100, 150, 200, and 250 ms. Analysis of covariance revealed significant (p velocity. Results indicate that INT is more advantageous than VOL for improving FRC and RFD, while changes in barbell velocity during dynamic strength testing are similarly improved by both protocols in resistance-trained men.

  15. The heart rate increase at the onset of high-work intensity exercise is accelerated by central blood volume loading.

    Science.gov (United States)

    Miyamoto, Tadayoshi; Oshima, Yoshitake; Ikuta, Komei; Kinoshita, Hiroshi

    2006-01-01

    Using a water immersion (WI) method, the combined effect of central blood volume (CBV) loading and work intensity on the time course of heart rate (HR) at the onset of upright dynamic exercise was investigated. Seven males cranked a cycle ergometer for 12 min using their un-immersed arms at low-, moderate- and high-work intensities, followed by a 12-min rest. For WI, the pre-exercise resting cardiac output increased by 36%, while HR decreased by 22% [from 76.8 (10.4) to 59.6 (9.8) beats/min]. WI also increased the high-frequency (HF, 0.15-0.40 Hz) component of the HR variability, suggesting an increased vagal activity. During the initial 2 min of the exercise period at low-work intensity, HR increased by 34.9 and 25.8% in the WI and control conditions, respectively. These were 117 and 73% at high-work intensity, indicating more accelerated HR with WI than the control. The plasma norepinephrine concentration increased less during high-work intensity exercise during WI, as compared to exercise during control conditions. In conclusion, the HR increase at the onset of high-work intensity exercise is accelerated by CBV loading but not at low intensity, possibly reflecting vago-sympathetic interaction and reduced baroreflex sensitivity.

  16. Components of Particle Emissions from Light-Duty Spark-Ignition Vehicles with Varying Aromatic Content and Octane Rating in Gasoline.

    Science.gov (United States)

    Short, Daniel Z; Vu, Diep; Durbin, Thomas D; Karavalakis, Georgios; Asa-Awuku, Akua

    2015-09-01

    Typical gasoline consists of varying concentrations of aromatic hydrocarbons and octane ratings. However, their impacts on particulate matter (PM) such as black carbon (BC) and water-soluble and insoluble particle compositions are not well-defined. This study tests seven 2012 model year vehicles, which include one port fuel injection (PFI) configured hybrid vehicle, one PFI vehicle, and six gasoline direct injection (GDI) vehicles. Each vehicle was driven on the Unified transient testing cycle (UC) using four different fuels. Three fuels had a constant octane rating of 87 with varied aromatic concentrations at 15%, 25%, and 35%. A fourth fuel with higher octane rating, 91, contained 35% aromatics. BC, PM mass, surface tension, and water-soluble organic mass (WSOM) fractions were measured. The water-insoluble mass (WIM) fraction of the vehicle emissions was estimated. Increasing fuel aromatic content increases BC emission factors (EFs) of transient cycles. BC concentrations were higher for the GDI vehicles than the PFI and hybrid vehicles, suggesting a potential climate impact for increased GDI vehicle production. Vehicle steady-state testing showed that the hygroscopicity of PM emissions at high speeds (70 mph; κ > 1) are much larger than emissions at low speeds (30 mph; κ < 0.1). Iso-paraffin content in the fuels was correlated to the decrease in WSOM emissions. Both aromatic content and vehicle speed increase the amount of hygroscopic material found in particle emissions.

  17. COMPARISON OF Hα AND UV STAR FORMATION RATES IN THE LOCAL VOLUME: SYSTEMATIC DISCREPANCIES FOR DWARF GALAXIES

    International Nuclear Information System (INIS)

    Lee, Janice C.; Gil de Paz, Armando; Tremonti, Christy; Walter, Fabian; Kennicutt, Robert C.; Bothwell, Matthew; Johnson, Benjamin; Salim, Samir; Calzetti, Daniela; Dalcanton, Julianne; Dale, Daniel; Engelbracht, Chad; Funes, S. J. Jose G.; Sakai, Shoko; Skillman, Evan; Weisz, Daniel; Van Zee, Liese

    2009-01-01

    Using a complete sample of ∼300 star-forming galaxies within 11 Mpc of the Milky Way, we evaluate the consistency between star formation rates (SFRs) inferred from the far ultraviolet (FUV) non-ionizing continuum and Hα nebular emission, assuming standard conversion recipes in which the SFR scales linearly with luminosity at a given wavelength. Our analysis probes SFRs over 5 orders of magnitude, down to ultra-low activities on the order of ∼10 -4 M sun yr -1 . The data are drawn from the 11 Mpc Hα and Ultraviolet Galaxy Survey (11HUGS), which has obtained Hα fluxes from ground-based narrowband imaging, and UV fluxes from imaging with GALEX. For normal spiral galaxies (SFR ∼ 1 M sun yr -1 ), our results are consistent with previous work which has shown that FUV SFRs tend to be lower than Hα SFRs before accounting for internal dust attenuation, but that there is relative consistency between the two tracers after proper corrections are applied. However, a puzzle is encountered at the faint end of the luminosity function. As lower luminosity dwarf galaxies, roughly less active than the Small Magellanic Cloud, are examined, Hα tends to increasingly underpredict the total SFR relative to the FUV. The trend is evident prior to corrections for dust attenuation, which affects the FUV more than the nebular Hα emission, so this general conclusion is robust to the effects of dust. Although past studies have suggested similar trends, this is the first time this effect is probed with a statistical sample for galaxies with SFR ∼ sun yr -1 . By SFR ∼ 0.003 M sun yr -1 , the average Hα-to-FUV flux ratio is lower than expected by a factor of two, and at the lowest SFRs probed, the ratio exhibits an order of magnitude discrepancy for the handful of galaxies that remain in the sample. A range of standard explanations does not appear to be able to fully account for the magnitude of the systematic. Some recent work has argued for a stellar initial mass function which

  18. Influence of primary α-phase volume fraction on the mechanical properties of Ti-6Al-4V alloy at different strain rates and temperatures

    Science.gov (United States)

    Ren, Yu; Zhou, Shimeng; Luo, Wenbo; Xue, Zhiyong; Zhang, Yajing

    2018-03-01

    Bimodal microstructures with primary α-phase volume fractions ranging from 14.3% to 57.1% were gained in Ti-6Al-4V (Ti-64) alloy through annealed in two-phase region at various temperatures below the β-transus point. Then the influence of the primary α-phase volume fraction on the mechanical properties of Ti-64 were studied. The results show that, at room temperature and a strain rate of 10‑3 s‑1, the yield stress decreases but the fracture strain augments with added primary α-phase volume fraction. The equiaxed primary α-phase possesses stronger ability to coordinate plastic deformation, leading to the improvement of the ductile as well as degradation of the strength of Ti-64 with higher primary α-phase volume fraction. As the temperature goes up to 473 K, the quasi-static yield stress and ultimate strength decrease first and then increase with the incremental primary α-phase volume fraction, due to the interaction between the work hardening and the softening caused by the DRX and the growth of the primary α-phase. At room temperature and a strain rate of 3×103 s‑1, the varying pattern of strength with the primary α-phase volume fraction resembles that at a quasi-static strain rate. However, the flow stress significantly increases but the strain-hardening rate decreases compared to those at quasi-static strain rate due to the competition between the strain rate hardening and the thermal softening during dynamic compression process.

  19. Should measurement of maximum urinary flow rate and residual urine volume be a part of a "minimal care" assessment programme in female incontinence?

    DEFF Research Database (Denmark)

    Sander, Pia; Mouritsen, L; Andersen, J Thorup

    2002-01-01

    OBJECTIVE: The aim of this study was to evaluate the value of routine measurements of urinary flow rate and residual urine volume as a part of a "minimal care" assessment programme for women with urinary incontinence in detecting clinical significant bladder emptying problems. MATERIAL AND METHODS....... Twenty-six per cent had a maximum flow rate less than 15 ml/s, but only 4% at a voided volume > or =200 ml. Residual urine more than 149 ml was found in 6%. Two women had chronic retention with overflow incontinence. Both had typical symptoms with continuous leakage, stranguria and chronic cystitis...

  20. A study of toxic emissions from a coal-fired power plant utilizing an ESP/Wet FGD system. Volume 1, Sampling, results, and special topics: Final report

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    This was one of a group of assessments of toxic emissions from coal-fired power plants, conducted for DOE-PETC in 1993 as mandated by the 1990 Clean Air Act. It is organized into 2 volumes; Volume 1 describes the sampling effort, presents the concentration data on toxic chemicals in several power plant streams, and reports the results of evaluations and calculations. The study involved solid, liquid, and gaseous samples from input, output, and process streams at Coal Creek Station Unit No. 1, Underwood, North Dakota (1100 MW mine-mouth plant burning lignite from the Falkirk mine located adjacent to the plant). This plant had an electrostatic precipitator and a wet scrubber flue gas desulfurization unit. Measurements were conducted on June 21--24, 26, and 27, 1993; chemicals measured were 6 major and 16 trace elements (including Hg, Cr, Cd, Pb, Se, As, Be, Ni), acids and corresponding anions (HCl, HF, chloride, fluoride, phosphate, sulfate), ammonia and cyanide, elemental C, radionuclides, VOCs, semivolatiles (incl. PAH, polychlorinated dioxins, furans), and aldehydes. Volume 2: Appendices includes process data log sheets, field sampling data sheets, uncertainty calculations, and quality assurance results.

  1. Experimental characterization of true spontaneous emission rate of optically-pumped InGaAs/GaAs quantum-well laser structure

    Directory of Open Access Journals (Sweden)

    Q.-N. Yu

    2017-08-01

    Full Text Available In this paper, an experimental approach to acquiring true spontaneous emission rate of optically-pumped InGaAs/GaAs quantum-well laser structure is described. This method is based on a single edge-emitting laser chip with simple sample processing. The photoluminescence spectra are measured at both facets of the edge-emitting device and transformed to the spontaneous emission rate following the theory described here. The unusual double peaks appearing in the spontaneous emission rate spectra are observed for the InGaAs/GaAs quantum-well structure. The result is analyzed in terms of Indium-rich island and Model-Solid theories. The proposed method is suitable for electrically-pumped quantum-well laser structures, as well.

  2. Rates of volcanic CO2 degassing from airborne determinations of SO2 Emission rates and plume CO2SO2: test study at Pu′u ′O′o Cone, Kilauea Volcano, Hawaii

    Science.gov (United States)

    Gerlach, Terrence M.; McGee, Kenneth A.; Sutton, A. Jefferson; Elias, Tamar

    1998-01-01

    We present an airborne method that eliminates or minimizes several disadvantages of the customary plume cross-section sampling method for determining volcanic CO2 emission rates. A LI-COR CO2analyzer system (LICOR), a Fourier transform infrared spectrometer system (FTIR), and a correlation spectrometer (COSPEC) were used to constrain the plume CO2/SO2 and the SO2 emission rate. The method yielded a CO2 emission rate of 300 td−1 (metric tons per day) for Pu′u ′O′o cone, Kilauea volcano, on 19 September 1995. The CO2/SO2 of 0.20 determined from airborne LICOR and FTIR plume measurements agreed with the CO2/SO2 of 204 ground-based samples collected from vents over a 14-year period since the Pu′u ′O′o eruption began in January 1983.

  3. Compilation of air-pollutant emission factors. Volume 1. Stationary point and area sources. Fourth edition. Supplement D

    International Nuclear Information System (INIS)

    Joyner, W.M.

    1991-09-01

    In the Supplement to the Fourth Edition of AP-42, new or revised emissions data are presented for Natural Gas Combustion; Residential Fireplaces, Residential Wood Stoves; Refuse Combustion; Nonindustrial Surface Coating; Waste Water Collection, Treatment and Storage; Polyvinyl Chloride and Polypropylene; Poly(ethylene terephthalate); Polystyrene; Ammonium Phosphates; Portland Cement Manufacturing; Sand and Gravel Processing; Western Surface Coal Mining; Wildfires and Prescribed Burning; Wet Cooling Towers and Industrial Flares

  4. Cerebral blood volume reactivity to hypercapnia measured with 11C-labelled carboxyhemoglobin and positron emission tomography. Chapter 8

    International Nuclear Information System (INIS)

    Kanno, Iwao; Uemera, Kazuo; Murakami, Matsutaro; Shishido, Fumio; Tomura, Noriaki

    1988-01-01

    The purpose of the present study to examine the regionality of the CBV reactivity to changes in PaCO2 employing 11C-labelled carboxyhemoglobin and positron emission tomography (PET). The study was caried out using sequential scans obtained by PET followinng a single administration by the 11CO inhalation method during which activation of either hypercapnia or hypocapnia was induced in the subject. 7 refs.; 6 figs.; 2 tabs

  5. Glomerular filtration rate in relation to extracellular fluid volume: similarity between 99mTc-DTPA and inulin

    International Nuclear Information System (INIS)

    Gunasekera, R.D.; Allison, D.J.; Peters, A.M.

    1996-01-01

    The aim of the present study was to compare 99m Tc-DTPA plasma clearance kinetics with those of inulin, injected simultaneously, with respect especially to α 2 , rapidity of equilibration within the distribution volume and the components and size of the distribution volume. (orig./MG)

  6. A technique for manual definition of an irregular volume of interest in single photon emission computed tomography

    International Nuclear Information System (INIS)

    Fleming, J.S.; Kemp, P.M.; Bolt, L.

    1999-01-01

    A technique is described for manually outlining a volume of interest (VOI) in a three-dimensional SPECT dataset. Regions of interest (ROIs) are drawn on three orthogonal maximum intensity projections. Image masks based on these ROIs are backprojected through the image volume and the resultant 3D dataset is segmented to produce the VOI. The technique has been successfully applied in the exclusion of unwanted areas of activity adjacent to the brain when segmenting the organ in SPECT imaging using 99m Tc HMPAO. An example of its use for segmentation in tumour imaging is also presented. The technique is of value for applications involving semi-automatic VOI definition in SPECT. (author)

  7. Observation of temperatures and emission rates from the OH and O 2 nightglow over a southern high latitude station

    Science.gov (United States)

    Chung, J.-K.; Kim, Y. H.; Won, Y.-I.; Moon, B. K.; Oh, T. H.

    2006-01-01

    A Spectral Airglow Temperature Imager (SATI) was operated at King Sejong Station (62°13'S, 58°47'W), Korea Antarctic Research Station during the period of March, 2002-September, 2003. We analyze rotational temperatures and emission rates of the O 2 (0-1) and OH (6-2) nightglows obtained at 67 nights with clear sky lasting more than 4 h. A spectral analysis of the dataset shows two dominant oscillations with periods of 4 and 6 h. The 6-h oscillations have a nearly constant phase, whereas the 4-h oscillations have nearly random phases. Although the harmonic periods of both oscillations are suggestive of tidal origin, the 4-h oscillation may have interference by other sources such as gravity waves. The 6-h oscillations could be interpreted as zonally symmetric non-migrating tides because migrating tides except high order modes have very weak amplitudes at high latitudes according to the classical tidal theory. For most cases of the observed oscillations the temperature peak leads the intensity peak, which is consistent with theoretical models for zonally symmetric tides, but contrary to other theoretical models for waves. It is needed to resolve among theoretical models whether or not zonally symmetric tide cause temperature variation prior to intensity variation in mesospheric airglows.

  8. Low Goiter Rate Associated with Small Average Thyroid Volume in Schoolchildren after the Elimination of Iodine Deficiency Disorders.

    Directory of Open Access Journals (Sweden)

    Peihua Wang

    Full Text Available After the implementation of the universal salt iodization (USI program in 1996, seven cross-sectional school-based surveys have been conducted to monitor iodine deficiency disorders (IDD among children in eastern China.This study aimed to examine the correlation of total goiter rate (TGR with average thyroid volume (Tvol and urinary iodine concentration (UIC in Jiangsu province after IDD elimination.Probability-proportional-to-size sampling was applied to select 1,200 children aged 8-10 years old in 30 clusters for each survey in 1995, 1997, 1999, 2001, 2002, 2005, 2009 and 2011. We measured Tvol using ultrasonography in 8,314 children and measured UIC (4,767 subjects and salt iodine (10,184 samples using methods recommended by the World Health Organization. Tvol was used to calculate TGR based on the reference criteria specified for sex and body surface area (BSA.TGR decreased from 55.2% in 1997 to 1.0% in 2009, and geometric means of Tvol decreased from 3.63 mL to 1.33 mL, along with the UIC increasing from 83 μg/L in 1995 to 407 μg/L in 1999, then decreasing to 243 μg/L in 2005, and then increasing to 345 μg/L in 2011. In the low goiter population (TGR 300 μg/L was associated with a smaller average Tvol in children.After IDD elimination in Jiangsu province in 2001, lower TGR was associated with smaller average Tvol. Average Tvol was more sensitive than TGR in detecting the fluctuation of UIC. A UIC of 300 μg/L may be defined as a critical value for population level iodine status monitoring.

  9. Evaluation of left ventricular function and volumes in patients with ischaemic cardiomyopathy: gated single-photon emission computed tomography versus two-dimensional echocardiography

    International Nuclear Information System (INIS)

    Vourvouri, E.C.; Poldermans, D.; Sianos, G.; Sozzi, F.B.; Schinkel, A.F.L.; Sutter, J. de; Roelandt, J.R.T.C.; Bax, J.J.; Parcharidis, G.; Valkema, R.

    2001-01-01

    The objective of this study was to perform a head-to-head comparison between two-dimensional (2D) echocardiography and gated single-photon emission computed tomography (SPET) for the evaluation of left ventricular (LV) function and volumes in patients with severe ischaemic LV dysfunction. Thirty-two patients with chronic ischaemic LV dysfunction [mean LV ejection fraction (EF) 25%±6%] were studied with gated SPET and 2D echocardiography. Regional wall motion was evaluated by both modalities and scored by two independent observers using a 16-segment model with a 5-point scoring system (1= normokinesia, 2= mild hypokinesia, 3= severe hypokinesia, 4= akinesia and 5= dyskinesia). LVEF and LV end-diastolic and end-systolic volumes were evaluated by 2D echocardiography using the Simpson's biplane discs method. The same parameters were calculated using quantitative gated SPET software (QGS, Cedars-Sinai Medical Center). The overall agreement between the two imaging modalities for assessment of regional wall motion was 69%. The correlations between gated SPET and 2D echocardiography for the assessment of end-diastolic and end-systolic volumes were excellent (r=0.94, P<0.01, and r=0.96, P<0.01, respectively). The correlation for LVEF was also good (r=0.83, P<0.01). In conclusion: in patients with ischaemic cardiomyopathy, close and significant relations between gated SPET and 2D echocardiography were observed for the assessment of regional and global LV function and LV volumes; gated SPET has the advantage that it provides information on both LV function/dimensions and perfusion. (orig.)

  10. Prognostic value of metabolic tumor volume as measured by fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography in nasopharyngeal carcinoma.

    Science.gov (United States)

    Yoon, Young-Ho; Lee, Seok-Hwan; Hong, Sung-Lyong; Kim, Seong-Jang; Roh, Hwan-Jung; Cho, Kyu-Sup

    2014-10-01

    The prognostic value of the tumor burden characterized by the metabolic tumor volume (MTV) remains under investigation in nasopharyngeal carcinoma (NPC). The purpose of this study was to evaluate the prognostic value of the maximum standardized uptake value (SUVmax ) and MTV according to metabolic volume threshold as measured by positron emission tomography (PET)/computed tomography (CT), and other clinical factors, in patients with NPC. This study was a retrospective chart review. We evaluated the association of SUVmax , MTV2.5 , MTV3.0 , and other clinical factors with overall survival (OS) using Kaplan-Meier and Cox regression models. (MTV2.5 and MTV3.0 are the volume of hypermetabolic tissue within the regions of gross tumor volumes with a SUV value greater than the threshold values of 2.5 and 3.0, respectively.) Higher MTV2.5 of 31.45 cm(3) and MTV3.0 of 23.01 cm(3) were associated with an increased risk of death (hazard ratio [HR] = 5.028; p = 0.029), although no significant relationship was found between SUVmax and OS. Interestingly, MTV3.0 was associated with OS in both the differentiated and undifferentiated groups, although MTV2.5 was only associated with OS in the undifferentiated group. Among the clinical parameters, only radiotherapy was associated with longer OS (HR = 12.124; p < 0.001). The MTV and radiotherapy could be prognostic values associated with OS. Particularly, MTV2.5 and MTV3.0 might be valuable metabolic parameters for predicting long-term survival in patients with NPC. Furthermore, MTV3.0 may be more useful because it can be applied irrespective of pathologic subtype. © 2014 ARS-AAOA, LLC.

  11. Optimized statistical parametric mapping for partial-volume-corrected amyloid positron emission tomography in patients with Alzheimer's disease and Lewy body dementia

    Science.gov (United States)

    Oh, Jungsu S.; Kim, Jae Seung; Chae, Sun Young; Oh, Minyoung; Oh, Seung Jun; Cha, Seung Nam; Chang, Ho-Jong; Lee, Chong Sik; Lee, Jae Hong

    2017-03-01

    We present an optimized voxelwise statistical parametric mapping (SPM) of partial-volume (PV)-corrected positron emission tomography (PET) of 11C Pittsburgh Compound B (PiB), incorporating the anatomical precision of magnetic resonance image (MRI) and amyloid β (A β) burden-specificity of PiB PET. First, we applied region-based partial-volume correction (PVC), termed the geometric transfer matrix (GTM) method, to PiB PET, creating MRI-based lobar parcels filled with mean PiB uptakes. Then, we conducted a voxelwise PVC by multiplying the original PET by the ratio of a GTM-based PV-corrected PET to a 6-mm-smoothed PV-corrected PET. Finally, we conducted spatial normalizations of the PV-corrected PETs onto the study-specific template. As such, we increased the accuracy of the SPM normalization and the tissue specificity of SPM results. Moreover, lobar smoothing (instead of whole-brain smoothing) was applied to increase the signal-to-noise ratio in the image without degrading the tissue specificity. Thereby, we could optimize a voxelwise group comparison between subjects with high and normal A β burdens (from 10 patients with Alzheimer's disease, 30 patients with Lewy body dementia, and 9 normal controls). Our SPM framework outperformed than the conventional one in terms of the accuracy of the spatial normalization (85% of maximum likelihood tissue classification volume) and the tissue specificity (larger gray matter, and smaller cerebrospinal fluid volume fraction from the SPM results). Our SPM framework optimized the SPM of a PV-corrected A β PET in terms of anatomical precision, normalization accuracy, and tissue specificity, resulting in better detection and localization of A β burdens in patients with Alzheimer's disease and Lewy body dementia.

  12. The Impact of Positron Emission Tomography/Computed Tomography in Edge Delineation of Gross Tumor Volume for Head and Neck Cancers

    International Nuclear Information System (INIS)

    Ashamalla, Hani; Guirgius, Adel; Bieniek, Ewa; Rafla, Sameer; Evola, Alex; Goswami, Ganesh; Oldroyd, Randall; Mokhtar, Bahaa; Parikh, Kapila

    2007-01-01

    Purpose: To study anatomic biologic contouring (ABC), using a previously described distinct halo, to unify volume contouring methods in treatment planning for head and neck cancers. Methods and Materials: Twenty-five patients with head and neck cancer at various sites were planned for radiation therapy using positron emission tomography/computed tomography (PET/CT). The ABC halo was used in all PET/CT scans to contour the gross tumor volume (GTV) edge. The CT-based GTV (GTV-CT) and PET/CT-based GTV (GTV-ABC) were contoured by two independent radiation oncologists. Results: The ABC halo was observed in all patients studied. The halo had a standard unit value of 2.19 ± 0.28. The mean halo thickness was 2.02 ± 0.21 mm. Significant volume modification (≥25%) was seen in 17 of 25 patients (68%) after implementation of GTV-ABC. Concordance among observers was increased with the use of the halo as a guide for GTV determination: 6 patients (24%) had a ≤10% volume discrepancy with CT alone, compared with 22 (88%) with PET/CT (p 3 in CT-based planning to 7.2 cm 3 in PET/CT-based planning (p < 0.001). Conclusions: Using the 'anatomic biologic halo' to contour GTV in PET/CT improves consistency among observers. The distinctive appearance of the described halo and its presence in all of the studied tumors make it attractive for GTV contouring in head and neck tumors. Additional studies are needed to confirm the correlation of the halo with presence of malignant cells

  13. A study of rumen water volume, rate of flow of water and rumen dry matter turnover time measurement by using 51Cr-labelled EDTA

    International Nuclear Information System (INIS)

    Krishna, G.; Ekern, A.

    1974-01-01

    Two fistulated adult sheep were infused with 100 μVi 51 Cr-EDTA, four hours after morning feeding, so as to calculate fumen water volume, and rate of flow of water from reticulo-rumen. The average figure of rumen water volume obtained was 2.191 litre, rate of flow of water expressed as volume per cent per hour was 7.55. The biological half-life of marker 51 Cr-EDTA in rumen was 9.34 hours. The percent recovery of infused dosage of 51 Cr-EDTA through faeces and urine was 66 and 5 during the period of four days after infusion. Dry matter turnover time in the rumen was 0.483 days. (author)

  14. A study of rumen water volume, rate of flow of water and rumen dry matter turnover time measurement by using /sup 51/Cr-labelled EDTA

    Energy Technology Data Exchange (ETDEWEB)

    Krishna, G; Ekern, A [Agricultural University of Norway. Dept. of Animal Nutrition

    1974-06-01

    Two fistulated adult sheep were infused with 100 ..mu..Vi /sup 51/Cr-EDTA, four hours after morning feeding, so as to calculate rumen water volume, and rate of flow of water from reticulo-rumen. The average figure of rumen water volume obtained was 2.191 litre, rate of flow of water expressed as volume per cent per hour was 7.55. The biological half-life of marker /sup 51/Cr-EDTA in rumen was 9.34 hours. The percent recovery of infused dosage of /sup 51/Cr-EDTA through feces and urine was 66 and 5 during the period of four days after infusion. Dry matter turnover time in the rumen was 0.483 days.

  15. Determination of radon emission rate with regard to energetic reconstruction of buildings; Bestimmung der Radonquellstaerke im Zusammenhang mit Massnahmen zur energetischen Sanierung von Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Neugebauer, Thomas; Grund, A.L.; Hingmann, H.; Buermeyer, J.; Grimm, V.; Breckow, J. [Technische Hochschule Mittelhessen (THM), Giessen (Germany). Inst. fuer Medizinische Physik und Strahlenschutz (IMPS)

    2015-07-01

    In frame of a project funded by the Federal Office for Radiation Protection (BfS) the influence of meteorological and room climate parameters and energetic reconstruction on the radon concentration inside buildings has been investigated. For this purpose parameters like temperature, air pressure, relative humidity and carbon dioxide concentration have been measured. The daily and seasonal variations of the radon concentration were influenced by the behaviour of the residents. A parameter less influenced by this behaviour is the radon emission rate. Complementary to the above mentioned project the method of determination of the radon emission rate has been developed in frame of a project funded by the Ministry of the Environment of Hesse (HMUKLV). With the improved method, it is possible to determine the radon emission rate on a continuous base. Therefore both, the radon concentration and the air exchange rate of a building have to be determined. For the verification of the method simulations and measurements have been performed. Additionally meteorological parameters have been recorded in order to evaluate possible influences on the radon emission rate.

  16. Nitrous oxide emissions in Midwest US maize production vary widely with band-injected N fertilizer rates, timing and nitrapyrin presence

    Science.gov (United States)

    Burzaco, Juan P.; Smith, Doug R.; Vyn, Tony J.

    2013-09-01

    Nitrification inhibitors have the potential to reduce N2O emissions from maize fields, but optimal results may depend on deployment of integrated N fertilizer management systems that increase yields achieved per unit of N2O lost. A new micro-encapsulated formulation of nitrapyrin for liquid N fertilizers became available to US farmers in 2010. Our research objectives were to (i) assess the impacts of urea-ammonium nitrate (UAN) management practices (timing, rate and nitrification inhibitor) and environmental variables on growing-season N2O fluxes and (ii) identify UAN treatment combinations that both reduce N2O emissions and optimize maize productivity. Field experiments near West Lafayette, Indiana in 2010 and 2011 examined three N rates (0, 90 and 180 kg N ha-1), two timings (pre-emergence and side-dress) and presence or absence of nitrapyrin. Mean cumulative N2O-N emissions (Q10 corrected) were 0.81, 1.83 and 3.52 kg N2O-N ha-1 for the rates of 0, 90 and 180 kg N ha-1, respectively; 1.80 and 2.31 kg N2O-N ha-1 for pre-emergence and side-dress timings, respectively; and 1.77 versus 2.34 kg N2O-N ha-1 for with and without nitrapyrin, respectively. Yield-scaled N2O-N emissions increased with N rates as anticipated (averaging 167, 204 and 328 g N2O-N Mg grain-1 for the 0, 90 and 180 kg N ha-1 rates), but were 22% greater with the side-dress timing than the pre-emergence timing (when averaged across N rates and inhibitor treatments) because of environmental conditions following later applications. Overall yield-scaled N2O-N emissions were 22% lower with nitrapyrin than without the inhibitor, but these did not interact with N rate or timing.

  17. Microwave remote sensing: Active and passive. Volume 2 - Radar remote sensing and surface scattering and emission theory

    Science.gov (United States)

    Ulaby, F. T.; Moore, R. K.; Fung, A. K.

    1982-01-01

    The fundamental principles of radar backscattering measurements are presented, including measurement statistics, Doppler and pulse discrimination techniques, and associated ambiguity functions. The operation of real and synthetic aperture sidelooking airborne radar systems is described, along with the internal and external calibration techniques employed in scattering measurements. Attention is given to the physical mechanisms responsible for the scattering emission behavior of homogeneous and inhomogeneous media, through a discussion of surface roughness, dielectric properties and inhomogeneity, and penetration depth. Simple semiempirical models are presented. Theoretical models involving greater mathematical sophistication are also given for extended ocean and bare soil surfaces, and the more general case of a vegetation canopy over a rough surface.

  18. Use of a Monte Carlo technique to complete a fragmented set of H2S emission rates from a wastewater treatment plant.

    Science.gov (United States)

    Schauberger, Günther; Piringer, Martin; Baumann-Stanzer, Kathrin; Knauder, Werner; Petz, Erwin

    2013-12-15

    The impact of ambient concentrations in the vicinity of a plant can only be assessed if the emission rate is known. In this study, based on measurements of ambient H2S concentrations and meteorological parameters, the a priori unknown emission rates of a tannery wastewater treatment plant are calculated by an inverse dispersion technique. The calculations are determined using the Gaussian Austrian regulatory dispersion model. Following this method, emission data can be obtained, though only for a measurement station that is positioned such that the wind direction at the measurement station is leeward of the plant. Using the inverse transform sampling, which is a Monte Carlo technique, the dataset can also be completed for those wind directions for which no ambient concentration measurements are available. For the model validation, the measured ambient concentrations are compared with the calculated ambient concentrations obtained from the synthetic emission data of the Monte Carlo model. The cumulative frequency distribution of this new dataset agrees well with the empirical data. This inverse transform sampling method is thus a useful supplement for calculating emission rates using the inverse dispersion technique. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Adaptive Support Ventilation May Deliver Unwanted Respiratory Rate-Tidal Volume Combinations in Patients with Acute Lung Injury Ventilated According to an Open Lung Concept

    NARCIS (Netherlands)

    Dongelmans, Dave A.; Paulus, Frederique; Veelo, Denise P.; Binnekade, Jan M.; Vroom, Margreeth B.; Schultz, Marcus J.

    2011-01-01

    Background: With adaptive support ventilation, respiratory rate and tidal volume (V(T)) are a function of the Otis least work of breathing formula. We hypothesized that adaptive support ventilation in an open lung ventilator strategy would deliver higher V(T)s to patients with acute lung injury.

  20. Computation of order and volume fill rates for a base stock inventory control system with heterogeneous demand to investigate which customer class gets the best service

    DEFF Research Database (Denmark)

    Larsen, Christian

    We consider a base stock inventory control system serving two customer classes whose demands are generated by two independent compound renewal processes. We show how to derive order and volume fill rates of each class. Based on assumptions about first order stochastic dominance we prove when one...

  1. Single impacts of keV fullerene ions on free standing graphene: Emission of ions and electrons from confined volume

    Energy Technology Data Exchange (ETDEWEB)

    Verkhoturov, Stanislav V.; Geng, Sheng; Schweikert, Emile A., E-mail: schweikert@chem.tamu.edu [Department of Chemistry, Texas A& M University, College Station, Texas 77843-3144 (United States); Czerwinski, Bartlomiej [Institute of Condensed Matter and Nanosciences–Bio and Soft Matter (IMCN/BSMA), Université Catholique de Louvain, 1 Croix du Sud, B-1348 Louvain-la-Neuve (Belgium); Applied Physics, Division of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, SE-971 87 Luleå (Sweden); Young, Amanda E. [Materials Characterization Facility, Texas A& M University, College Station, Texas 77843-3122 (United States); Delcorte, Arnaud [Institute of Condensed Matter and Nanosciences–Bio and Soft Matter (IMCN/BSMA), Université Catholique de Louvain, 1 Croix du Sud, B-1348 Louvain-la-Neuve (Belgium)

    2015-10-28

    We present the first data from individual C{sub 60} impacting one to four layer graphene at 25 and 50 keV. Negative secondary ions and electrons emitted in transmission were recorded separately from each impact. The yields for C{sub n}{sup −} clusters are above 10% for n ≤ 4, they oscillate with electron affinities and decrease exponentially with n. The result can be explained with the aid of MD simulation as a post-collision process where sufficient vibrational energy is accumulated around the rim of the impact hole for sputtering of carbon clusters. The ionization probability can be estimated by comparing experimental yields of C{sub n}{sup −} with those of C{sub n}{sup 0} from MD simulation, where it increases exponentially with n. The ionization probability can be approximated with ejecta from a thermally excited (3700 K) rim damped by cluster fragmentation and electron detachment. The experimental electron probability distributions are Poisson-like. On average, three electrons of thermal energies are emitted per impact. The thermal excitation model invoked for C{sub n}{sup −} emission can also explain the emission of electrons. The interaction of C{sub 60} with graphene is fundamentally different from impacts on 3D targets. A key characteristic is the high degree of ionization of the ejecta.

  2. 3rd stage seed-cotton cleaning system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  3. 2nd stage seed-cotton cleaning system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  4. 1st stage seed-cotton cleaning system PM10 emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  5. Battery condenser system PM10 emission factors and rates for cotton gins: Method 201A PM10 sizing cyclones

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that to characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study ...

  6. Evaluating four N2O emission algorithms in RZWQM2 in response to N rate on an irrigated corn field

    Science.gov (United States)

    Nitrous oxide (N2O) emissions from agricultural soils are major contributors to greenhouse gases. Correctly assessing the effects of the interactions between agricultural practices and environmental factors on N2O emissions is required for better crop and nitrogen (N) management. We used an enhanced...

  7. Effects of emission layer doping on the spatial distribution of charge and host recombination rate density in organic light emitting devices: A numerical study

    Science.gov (United States)

    Li, Yanli; Zhou, Maoqing; Zheng, Tingcai; Yao, Bo; Peng, Yingquan

    2013-12-01

    Based on drift-diffusion theory, a numerical model of the doping of a single energy level trap in the emission layer of an organic light emitting device (OLED) was developed, and the effects of doping of this single energy level trap on the distribution of the charge density, the recombination rate density, and the electric field in single- and double-layer OLEDs were studied numerically. The results show that by doping the n-type (p-type) emission layer with single energy electron (hole) traps, the distribution of the recombination rate density can be tuned and shifted, which is useful for improvement of the device performance by reduced electrode quenching or for realization of desirable special functions, e.g., emission spectrum tuning in multiple dye-doped white OLEDs.

  8. Effects of emission layer doping on the spatial distribution of charge and host recombination rate density in organic light emitting devices: A numerical study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanli; Zhou, Maoqing; Zheng, Tingcai; Yao, Bo [Institute of Microelectronics, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000 (China); Peng, Yingquan, E-mail: yqpeng@lzu.edu.cn [Institute of Microelectronics, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000 (China); Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2013-12-28

    Based on drift-diffusion theory, a numerical model of the doping of a single energy level trap in the emission layer of an organic light emitting device (OLED) was developed, and the effects of doping of this single energy level trap on the distribution of the charge density, the recombination rate density, and the electric field in single- and double-layer OLEDs were studied numerically. The results show that by doping the n-type (p-type) emission layer with single energy electron (hole) traps, the distribution of the recombination rate density can be tuned and shifted, which is useful for improvement of the device performance by reduced electrode quenching or for realization of desirable special functions, e.g., emission spectrum tuning in multiple dye-doped white OLEDs.

  9. Effects of emission layer doping on the spatial distribution of charge and host recombination rate density in organic light emitting devices: A numerical study

    International Nuclear Information System (INIS)

    Li, Yanli; Zhou, Maoqing; Zheng, Tingcai; Yao, Bo; Peng, Yingquan

    2013-01-01

    Based on drift-diffusion theory, a numerical model of the doping of a single energy level trap in the emission layer of an organic light emitting device (OLED) was developed, and the effects of doping of this single energy level trap on the distribution of the charge density, the recombination rate density, and the electric field in single- and double-layer OLEDs were studied numerically. The results show that by doping the n-type (p-type) emission layer with single energy electron (hole) traps, the distribution of the recombination rate density can be tuned and shifted, which is useful for improvement of the device performance by reduced electrode quenching or for realization of desirable special functions, e.g., emission spectrum tuning in multiple dye-doped white OLEDs

  10. Normal expiratory flow rate and lung volumes in patients with combined emphysema and interstitial lung disease: a case series and literature review.

    Science.gov (United States)

    Heathcote, Karen L; Cockcroft, Donald W; Fladeland, Derek A; Fenton, Mark E

    2011-01-01

    Pulmonary function tests in patients with idiopathic pulmonary fibrosis characteristically show a restrictive pattern including small lung volumes and increased expiratory flow rates resulting from a reduction in pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. When the diseases coexist, pulmonary volumes are compensated, and a smaller than expected reduction or even normal lung volumes can be found. The present report describes 10 patients with progressive breathlessness, three of whom experienced severe limitation in their quality of life. All patients showed lung interstitial involvement and emphysema on computed tomography scan of the chest. The 10 patients showed normal spirometry and lung volumes with severe compromise of gas exchange. Normal lung volumes do not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  11. Normal Expiratory Flow Rate and Lung Volumes in Patients with Combined Emphysema and Interstitial Lung Disease: A Case Series and Literature Review

    Directory of Open Access Journals (Sweden)

    Karen L Heathcote

    2011-01-01

    Full Text Available Pulmonary function tests in patients with idiopathic pulmonary fibrosis characteristically show a restrictive pattern including small lung volumes and increased expiratory flow rates resulting from a reduction in pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. When the diseases coexist, pulmonary volumes are compensated, and a smaller than expected reduction or even normal lung volumes can be found. The present report describes 10 patients with progressive breathlessness, three of whom experienced severe limitation in their quality of life. All patients showed lung interstitial involvement and emphysema on computed tomography scan of the chest. The 10 patients showed normal spirometry and lung volumes with severe compromise of gas exchange. Normal lung volumes do not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  12. Estimation of time-varying pollutant emission rates in a ventilated enclosure: inversion of a reduced model obtained by experimental application of the modal identification method

    International Nuclear Information System (INIS)

    Girault, M; Maillet, D; Bonthoux, F; Galland, B; Martin, P; Braconnier, R; Fontaine, J R

    2008-01-01

    A method is proposed for the estimation of time-varying emission rates of pollutant sources in a ventilated enclosure, through the resolution of an inverse forced convection problem. Unsteady transport–diffusion of the pollutant is considered, with the assumption of a stationary velocity field remaining unchanged during emission (passive contaminant). The pollutant transport equation is therefore linear with respect to concentration. The source's location is also supposed to be known. As the first step, a reduced model (RM) linking concentrations at a set of control points to emission rates of sources is identified from experimental data by using the modal identification method (MIM). This parameter estimation problem uses transient contaminant concentration measurements made at control points inside the ventilated enclosure, corresponding to increasing and decreasing steps of emission rates. Such experimental modelling allows us to avoid dealing with a CFD code involving turbulence modelling and to get rid of uncertainties about sensors position. In a second step, the identified RM is used to solve an inverse forced convection problem: from contaminant concentration measured at the same control points, rates of sources emitting simultaneously are estimated with a sequential in time algorithm using future time steps

  13. 100 μm and 160 μm emission as resolved star-formation rate estimators in M 33 (HERM33ES)

    NARCIS (Netherlands)

    Boquien, M.; Calzetti, D.; Kramer, C.; Xilouris, E. M.; Bertoldi, F.; Braine, J.; Buchbender, C.; Combes, F.; Israel, F.; Koribalski, B.; Lord, S.; Quintana-Lacaci, G.; Relano, M.; Roellig, M.; Stacey, G.; Tabatabaei, F. S.; Tilanus, R.P.J.; van der Tak, F.; Verley, S.; van der Werf, Paul P.

    Context. Over the past few years several studies have provided estimates of the SFR (star-formation rate) or the total infrared luminosity from just one infrared band. However these relations are generally derived for entire galaxies, which are known to contain a large scale diffuse emission that is

  14. Carbon emissions and sequestration in forests: Case studies from seven developing countries. Volume 3, India and China

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, W.; Sathaye, J. [eds.] [Lawrence Berkeley Lab., CA (United States); Ravindranath, N.H.; Somashekhar, B.S.; Gadgil, M. [Indian Inst. of Science, Bangalore, (India). Center for Ecological Sciences and ASTRA; Deying, Xu [Chinese Academy of Forestry, Beijing, (China). Research Inst. of Forestry

    1992-08-01

    As part of the effort to understand the sources of carbon dioxide and other major greenhouse gases, the Tropical Forestry and Global Climate Change Research Network (F-7) was established. The countries taking part in the F-7 Network -- Brazil, China, India, Indonesia, Malaysia, Mexico, Nigeria and Thailand -- possess large tracts of tropical forests and together experience the bulk of large scale tropical deforestation. Integreation of work of indigenous researchers and institutions from the participating countries should allow for the gathering of on-site information into the more general and universally available base of knowledge. The information contained in this report represents the results of the first phase of the F-7 project, which had the explicit aim of providing quantitative data on forestry-related carbon emissions from India and China.

  15. Effect of injection pressure on heat release rate and emissions in CI engine using orange skin powder diesel solution

    International Nuclear Information System (INIS)

    Purushothaman, K.; Nagarajan, G.

    2009-01-01

    Experiments have been conducted to study the effect of injection pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with Orange Skin Powder Diesel Solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and emissions. In the present investigation the injection pressure was varied with 30% OSPDS and the combustion, performance and emissions characteristics were compared with those of diesel fuel. The different injection pressures studied were 215 bar, 235 bar and 255 bar. The results showed that the cylinder pressure with 30% OSPDS at 235 bar fuel injection pressure, was higher than that of diesel fuel as well as at other injection pressures. Similarly, the ignition delay was longer and with shorter combustion duration with 30% OSPDS at 235 bar injection pressure. The brake thermal efficiency was better at 235 bar than that of other fuel injection pressures with OSPDS and lower than that of diesel fuel. The NO x emission with 30% OSPDS was higher at 235 bar. The hydrocarbon and CO emissions were lower with 30% OSPDS at 235 bar. The smoke emission with 30% OSPDS was marginally lower at 235 bar and marginally higher at 215 bar than for diesel fuel. The combustion, performance and emission characteristics of the engine operating on the test fuels at 235 bar injection pressure were better than other injection pressures

  16. Measurement of absolute myocardial blood flow with H215O and dynamic positron-emission tomography. Strategy for quantification in relation to the partial-volume effect

    International Nuclear Information System (INIS)

    Iida, H.; Kanno, I.; Takahashi, A.

    1988-01-01

    An in vivo technique was developed for measuring the absolute myocardial blood flow with H 2 15 O and dynamic positron-emission tomography. This technique was based on a new model involving the concept of the tissue fraction, which was defined as the fraction of the tissue mass in the volume of the region of interest. The myocardium was imaged dynamically by positron-emission tomography, starting at the time of intravenous bolus injection of H 2 15 O. The arterial input function was measured continuously with a beta-ray detector. A separate image after C 15 O inhalation was also obtained for correction of the H 2 15 O radioactivity in the blood. The absolute myocardial blood flow and the tissue fraction were calculated for 15 subjects with a kinetic technique under region-of-interest analysis. These results seem consistent with their coronary angiographic findings. The mean value of the measured absolute myocardial blood flows in normal subjects was 0.95 +/- 0.09 ml/min/g. This technique detected a diffuse decrease of myocardial blood flow in patients with triple-vessel disease

  17. Global Scale Attribution of Anthropogenic and Natural Dust Sources and their Emission Rates Based on MODIS Deep Blue Aerosol Products

    Science.gov (United States)

    Ginoux, Paul; Prospero, Joseph M.; Gill, Thomas E.; Hsu, N. Christina; Zhao, Ming

    2012-01-01

    Our understanding of the global dust cycle is limited by a dearth of information about dust sources, especially small-scale features which could account for a large fraction of global emissions. Here we present a global-scale high-resolution (0.1 deg) mapping of sources based on Moderate Resolution Imaging Spectroradiometer (MODIS) Deep Blue estimates of dust optical depth in conjunction with other data sets including land use. We ascribe dust sources to natural and anthropogenic (primarily agricultural) origins, calculate their respective contributions to emissions, and extensively compare these products against literature. Natural dust sources globally account for 75% of emissions; anthropogenic sources account for 25%. North Africa accounts for 55% of global dust emissions with only 8% being anthropogenic, mostly from the Sahel. Elsewhere, anthropogenic dust emissions can be much higher (75% in Australia). Hydrologic dust sources (e.g., ephemeral water bodies) account for 31% worldwide; 15% of them are natural while 85% are anthropogenic. Globally, 20% of emissions are from vegetated surfaces, primarily desert shrublands and agricultural lands. Since anthropogenic dust sources are associated with land use and ephemeral water bodies, both in turn linked to the hydrological cycle, their emissions are affected by climate variability. Such changes in dust emissions can impact climate, air quality, and human health. Improved dust emission estimates will require a better mapping of threshold wind velocities, vegetation dynamics, and surface conditions (soil moisture and land use) especially in the sensitive regions identified here, as well as improved ability to address small-scale convective processes producing dust via cold pool (haboob) events frequent in monsoon regimes.

  18. Two years monitoring of soil N_{2}O emissions on durum wheat in a Mediterranean area: the effect of tillage intensity and N-fertilizer rate.

    Science.gov (United States)

    Volpi, Iride; Bosco, Simona; Triana, Federico; Di Nasso, Nicoletta Nassi o.; Laville, Patricia; Virgili, Giorgio; Bonari, Enrico

    2016-04-01

    Evaluating the magnitude and the key factors affecting N2O emissions from agriculture has a scientific and practical relevance, in fact emissions from agricultural and natural soils account for 56-70% of all global N2O sources (Syakila and Kroeze, 2011). Moreover, the necessity to increase the food production rate minimizing greenhouse gas emissions require a deeper understanding of the effect of the agricultural practices on direct soil emissions. Therefore, the aim of this work is to assess the effect of tillage intensity and nitrogen rate on soil N2O emissions on durum wheat. A two years monitoring campaign was carried out using a high-sensibility transportable instrument developed within the LIFE+ "Improved flux Prototypes for N2O emission from Agriculture" IPNOA project (Bosco et al., 2015; Laville et al., 2015). The project aims at improving the measurement technique of N2O flux directly in field using the flow-through non-steady state chamber technique. The monitoring campaign on durum wheat lasted for two growing seasons and two fallow periods (2013-14 and 2014-15). Treatment on the main plot was tillage intensity with two levels, ploughing and minimum tillage, and three different nitrogen rates were distributed to the subplots (N0: 0 kg ha-1, N1: 110 kg ha-1, N2: 170 kg ha-1). Ancillary measurements concerned meteorological data, soil temperature and moisture, NO3-, NH4+ soil concentration. Main results of the two years highlighted N rate as the main driver for both N2O daily flux and cumulative emissions during the growing season, while in the fallow period treatments did not affect the emission magnitude. Tillage intensity was not a key factor for N2O emissions. N2O emissions were significantly different in the two years. In particular, cumulative emissions of 2013-14 were about five times higher than in 2014-15, respectively on average 2885±260 g N-N2O ha-1 and 534±53 g N-N2O ha-1 for a similar monitoring period of about 300 days. Differences could be

  19. Effects of Respiration-Averaged Computed Tomography on Positron Emission Tomography/Computed Tomography Quantification and its Potential Impact on Gross Tumor Volume Delineation

    International Nuclear Information System (INIS)

    Chi, Pai-Chun Melinda; Mawlawi, Osama; Luo Dershan; Liao Zhongxing; Macapinlac, Homer A.; Pan Tinsu

    2008-01-01

    Purpose: Patient respiratory motion can cause image artifacts in positron emission tomography (PET) from PET/computed tomography (CT) and change the quantification of PET for thoracic patients. In this study, respiration-averaged CT (ACT) was used to remove the artifacts, and the changes in standardized uptake value (SUV) and gross tumor volume (GTV) were quantified. Methods and Materials: We incorporated the ACT acquisition in a PET/CT session for 216 lung patients, generating two PET/CT data sets for each patient. The first data set (PET HCT /HCT) contained the clinical PET/CT in which PET was attenuation corrected with a helical CT (HCT). The second data set (PET ACT /ACT) contained the PET/CT in which PET was corrected with ACT. We quantified the differences between the two datasets in image alignment, maximum SUV (SUV max ), and GTV contours. Results: Of the patients, 68% demonstrated respiratory artifacts in the PET HCT , and for all patients the artifact was removed or reduced in the corresponding PET ACT . The impact of respiration artifact was the worst for lesions less than 50 cm 3 and located below the dome of the diaphragm. For lesions in this group, the mean SUV max difference, GTV volume change, shift in GTV centroid location, and concordance index were 21%, 154%, 2.4 mm, and 0.61, respectively. Conclusion: This study benchmarked the differences between the PET data with and without artifacts. It is important to pay attention to the potential existence of these artifacts during GTV contouring, as such artifacts may increase the uncertainties in the lesion volume and the centroid location

  20. Analysis of regional cerebral blood flow and distribution volume in Machado-Joseph disease by iodine-{sup 123}I IMP single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Tsunemi; Nakajima, Takashi; Fukuhara, Nobuyoshi [National Saigata Hospital, Ohagata, Niigata (Japan)

    2001-09-01

    Machado-Joseph disease (MJD) is an autosomal dominant spinocerebellar ataxia. Its clinical features vary greatly in different generations of the same family. Regional cerebral blood flow (rCBF) and distribution volume (V{sub d}) in the pons, cerebellum, and cerebral cortex were measured in 12 patients with MJD by autoradiography (ARG) and the table look-up (TLU) method of iodine-123 IMP ({sup 123}I-IMP) single photon emission computed tomography (SPECT). Representative cases were as follows: A 46-year-old woman first experienced gait ataxia at age 38. Computed tomography (CT) and magnetic resonance imaging (MRI) showed no atrophy in the pons or cerebellum, but rCBF measured by the {sup 123}I-IMP SPECT ARG method detected hypoperfusion in the pons, and cerebellar vermis and hemisphere. A 76-year-old woman first experienced gait ataxia at age 69. CT and MRI findings showed severe atrophy in the pons, and cerebellar vermis and hemisphere. Moreover, rCBF was decreased in the pons, whereas it was not decreased in the cerebellar vermis and hemisphere. In the pons of patients with MJD, rCBF was markedly decreased regardless of disease severity. Because this SPECT finding for the pons looked like a 'dot', we have called it the 'pontine dot sign'. In the MJD group, rCBF was significantly decreased in the pons (Student's t test, p<0.01) and cerebellar vermis (p<0.05). The V{sub d} was also significantly decreased in the pons (p<0.005) in comparison with that for normal subjects. Pearson's correlation analysis yielded a significant relationship between the rCBF in the pons and age at onset (r=0.578, p<0.05). There was a strong correlation between the V{sub d} for the pons and age at onset (r=0.59, p<0.05). Person's correlation analysis also showed a significant relationship between the V{sub d} in the cerebellar hemispheres and International Cooperative Ataxia Rating Scale (r=0.644, p<0.05). The pontine rCBFs in patients with early onset MJD

  1. Improved optical flow velocity analysis in SO2 camera images of volcanic plumes – implications for emission-rate retrievals investigated at Mt Etna, Italy and Guallatiri, Chile

    Directory of Open Access Journals (Sweden)

    J. Gliß

    2018-02-01

    Full Text Available Accurate gas velocity measurements in emission plumes are highly desirable for various atmospheric remote sensing applications. The imaging technique of UV SO2 cameras is commonly used to monitor SO2 emissions from volcanoes and anthropogenic sources (e.g. power plants, ships. The camera systems capture the emission plumes at high spatial and temporal resolution. This allows the gas velocities in the plume to be retrieved directly from the images. The latter can be measured at a pixel level using optical flow (OF algorithms. This is particularly advantageous under turbulent plume conditions. However, OF algorithms intrinsically rely on contrast in the images and often fail to detect motion in low-contrast image areas. We present a new method to identify ill-constrained OF motion vectors and replace them using the local average velocity vector. The latter is derived based on histograms of the retrieved OF motion fields. The new method is applied to two example data sets recorded at Mt Etna (Italy and Guallatiri (Chile. We show that in many cases, the uncorrected OF yields significantly underestimated SO2 emission rates. We further show that our proposed correction can account for this and that it significantly improves the reliability of optical-flow-based gas velocity retrievals. In the case of Mt Etna, the SO2 emissions of the north-eastern crater are investigated. The corrected SO2 emission rates range between 4.8 and 10.7 kg s−1 (average of 7.1  ±  1.3 kg s−1 and are in good agreement with previously reported values. For the Guallatiri data, the emissions of the central crater and a fumarolic field are investigated. The retrieved SO2 emission rates are between 0.5 and 2.9 kg s−1 (average of 1.3  ±  0.5 kg s−1 and provide the first report of SO2 emissions from this remotely located and inaccessible volcano.

  2. Positron emission tomography in cerebrovascular disease: The relationship between regional cerebral blood flow, blood volume and oxygen metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Herold, S.

    1985-03-01

    Positron emission tomography in cerebrovascular disease has demonstrated the importance of the relationship between regional cerebral blood flow and the cerebral metabolic activity. In acute stroke it has been found that within the first hours after the onset of symptoms cerebral blood flow in the affected area is more depressed than cerebral oxygen utilisation. This relative preservation of oxygen utilisation results from an increase in the oxygen extraction ratio far above its normal value. However, the oxygen extraction fraction subsequently falls in the following days indicating the transition from a situation of possibly reversible ischaemia to irreversible infarction. In patients with carotid occlusive disease an increase in the oxygen extraction ratio has been observed only in very few cases. It has been shown, however, that at an earlier stage the relationship between CBF and CBV (as CBF/CBV-ratio) provides a sensitive measure of diminished perfusion pressure which could be helpful for the selection of patients for EC-IC bypass surgery. In patients with sickle cell anaemia it has been found that oxygen delivery to the brain is maintained by an increase in cerebral blood flow, whereas the oxygen extraction ratio is not increased despite the presence of a low oxygen affinity haemoglobin. Preliminary observations in classical migraine suggest an ischaemic situation during the attack.

  3. Recent increases in the atmospheric growth rate and emissions of HFC-23 (CHF3 and the link to HCFC-22 (CHClF2 production

    Directory of Open Access Journals (Sweden)

    P. G. Simmonds

    2018-03-01

    Full Text Available High frequency measurements of trifluoromethane (HFC-23, CHF3, a potent hydrofluorocarbon greenhouse gas, largely emitted to the atmosphere as a by-product of the production of the hydrochlorofluorocarbon HCFC-22 (CHClF2, at five core stations of the Advanced Global Atmospheric Gases Experiment (AGAGE network, combined with measurements on firn air, old Northern Hemisphere air samples and Cape Grim Air Archive (CGAA air samples, are used to explore the current and historic changes in the atmospheric abundance of HFC-23. These measurements are used in combination with the AGAGE 2-D atmospheric 12-box model and a Bayesian inversion methodology to determine model atmospheric mole fractions and the history of global HFC-23 emissions. The global modelled annual mole fraction of HFC-23 in the background atmosphere was 28.9 ± 0.6 pmol mol−1 at the end of 2016, representing a 28 % increase from 22.6 ± 0.4 pmol mol−1 in 2009. Over the same time frame, the modelled mole fraction of HCFC-22 increased by 19 % from 199 ± 2 to 237 ± 2 pmol mol−1. However, unlike HFC-23, the annual average HCFC-22 growth rate slowed from 2009 to 2016 at an annual average rate of −0.5 pmol mol−1 yr−2. This slowing atmospheric growth is consistent with HCFC-22 moving from dispersive (high fractional emissions to feedstock (low fractional emissions uses, with HFC-23 emissions remaining as a consequence of incomplete mitigation from all HCFC-22 production.Our results demonstrate that, following a minimum in HFC-23 global emissions in 2009 of 9.6 ± 0.6, emissions increased to a maximum in 2014 of 14.5 ± 0.6 Gg yr−1 and then declined to 12.7 ± 0.6 Gg yr−1 (157 Mt CO2 eq. yr−1 in 2016. The 2009 emissions minimum is consistent with estimates based on national reports and is likely a response to the implementation of the Clean Development Mechanism (CDM to mitigate HFC-23 emissions by

  4. Recent increases in the atmospheric growth rate and emissions of HFC-23 (CHF3) and the link to HCFC-22 (CHClF2) production

    Science.gov (United States)

    Simmonds, Peter G.; Rigby, Matthew; McCulloch, Archie; Vollmer, Martin K.; Henne, Stephan; Mühle, Jens; O'Doherty, Simon; Manning, Alistair J.; Krummel, Paul B.; Fraser, Paul J.; Young, Dickon; Weiss, Ray F.; Salameh, Peter K.; Harth, Christina M.; Reimann, Stefan; Trudinger, Cathy M.; Steele, L. Paul; Wang, Ray H. J.; Ivy, Diane J.; Prinn, Ronald G.; Mitrevski, Blagoj; Etheridge, David M.

    2018-03-01

    High frequency measurements of trifluoromethane (HFC-23, CHF3), a potent hydrofluorocarbon greenhouse gas, largely emitted to the atmosphere as a by-product of the production of the hydrochlorofluorocarbon HCFC-22 (CHClF2), at five core stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, combined with measurements on firn air, old Northern Hemisphere air samples and Cape Grim Air Archive (CGAA) air samples, are used to explore the current and historic changes in the atmospheric abundance of HFC-23. These measurements are used in combination with the AGAGE 2-D atmospheric 12-box model and a Bayesian inversion methodology to determine model atmospheric mole fractions and the history of global HFC-23 emissions. The global modelled annual mole fraction of HFC-23 in the background atmosphere was 28.9 ± 0.6 pmol mol-1 at the end of 2016, representing a 28 % increase from 22.6 ± 0.4 pmol mol-1 in 2009. Over the same time frame, the modelled mole fraction of HCFC-22 increased by 19 % from 199 ± 2 to 237 ± 2 pmol mol-1. However, unlike HFC-23, the annual average HCFC-22 growth rate slowed from 2009 to 2016 at an annual average rate of -0.5 pmol mol-1 yr-2. This slowing atmospheric growth is consistent with HCFC-22 moving from dispersive (high fractional emissions) to feedstock (low fractional emissions) uses, with HFC-23 emissions remaining as a consequence of incomplete mitigation from all HCFC-22 production.Our results demonstrate that, following a minimum in HFC-23 global emissions in 2009 of 9.6 ± 0.6, emissions increased to a maximum in 2014 of 14.5 ± 0.6 Gg yr-1 and then declined to 12.7 ± 0.6 Gg yr-1 (157 Mt CO2 eq. yr-1) in 2016. The 2009 emissions minimum is consistent with estimates based on national reports and is likely a response to the implementation of the Clean Development Mechanism (CDM) to mitigate HFC-23 emissions by incineration in developing (non-Annex 1) countries under the Kyoto Protocol. Our derived cumulative

  5. Inter fraction variations in rectum and bladder volumes and dose distributions during high dose rate brachytherapy treatment of the uterine cervix investigated by repetitive CT-examinations

    International Nuclear Information System (INIS)

    Hellebust, Taran Paulsen; Dale, Einar; Skjoensberg, Ane; Olsen, Dag Rune

    2001-01-01

    Purpose: To evaluate variation of dose to organs at risk for patients receiving fractionated high dose rate gynaecological brachytherapy by using CT-based 3D treatment planning and dose-volume histograms (DVH). Materials and methods: Fourteen patients with cancer of the uterine cervix underwent three to six CT examinations (mean 4.9) during their course of high-dose-rate brachytherapy using radiographically compatible applicators. The rectal and bladder walls were delineated and DVHs were calculated. Results: Inter fraction variation of the bladder volume (CV mean =44.1%) was significantly larger than the inter fraction variation of the mean dose (CV mean =19.9%, P=0.005) and the maximum dose (CV mean =17.5%, P=0.003) of the bladder wall. The same trend was seen for rectum, although the figures were not significantly different. Performing CT examinations at four of seven brachytherapy fractions reduced the uncertainty to 4 and 7% for the bladder and rectal doses, respectively. A linear regression analysis showed a significant, negative relationship between time after treatment start and the whole bladder volume (P=0.018), whereas no correlation was found for the rectum. For both rectum and bladder a linear regression analysis revealed a significant, negative relationship between the whole volume and median dose (P<0.05). Conclusion: Preferably a CT examination should be provided at every fraction. However, this is logistically unfeasible in most institutions. To obtain reliable DVHs the patients will in the future undergo 3-4 CT examinations during the course of brachytherapy at our institution. Since this study showed an association between large bladder volumes and dose reductions, the patients will be treated with a standardized bladder volume

  6. CO{sub 2} emissions from developing countries: Better understanding the role of Energy in the long term. Volume 2, Argentina, Brazil, Mexico, and Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Ketoff, A.; Sathaye, J.; Goldman, N. [eds.

    1991-07-01

    Recent years have witnessed a growing recognition of the link between emissions of carbon dioxide (CO{sub 2}) and changes in the global climate. Of all anthropogenic activities, energy production and use generate the single largest portion of these greenhouse gases. Although developing countries currently account for a small share of global carbon emissions, their contribution is increasing rapidly. Due to the rapid expansion of energy demand in these nations, the developing world`s share in global modern energy use rose from 16 to 27 percent between 1970 and 1990. If the growth rates observed over the past 20 years persist energy demand in developing will surpass that in the countries of the Organization for Economic Cooperation and Development (OECD) early in the 21st century. The study seeks to examine the forces that galvanize the growth of energy use and carbon emissions, to assess the likely future levels of energy and CO{sub 2} in selected developing nations and to identify opportunities for restraining this growth. The purpose of this report is to provide the quantitative information needed to develop effective policy options, not to identify the options themselves. These individual studies were conducted fro Argentina, Brazil, Mexico and Venezuela in Latin America.

  7. Variation in critical care unit admission rates and outcomes for patients with acute coronary syndromes or heart failure among high- and low-volume cardiac hospitals.

    Science.gov (United States)

    van Diepen, Sean; Bakal, Jeffrey A; Lin, Meng; Kaul, Padma; McAlister, Finlay A; Ezekowitz, Justin A

    2015-02-27

    Little is known about cross-hospital differences in critical care units admission rates and related resource utilization and outcomes among patients hospitalized with acute coronary syndromes (ACS) or heart failure (HF). Using a population-based sample of 16,078 patients admitted to a critical care unit with a primary diagnosis of ACS (n=14,610) or HF (n=1467) between April 1, 2003 and March 31, 2013 in Alberta, Canada, we stratified hospitals into high (>250), medium (200 to 250), or low (<200) volume based on their annual volume of all ACS and HF hospitalization. The percentage of hospitalized patients admitted to critical care units varied across low, medium, and high-volume hospitals for both ACS and HF as follows: 77.9%, 81.3%, and 76.3% (P<0.001), and 18.0%, 16.3%, and 13.0% (P<0.001), respectively. Compared to low-volume units, critical care patients with ACS and HF admitted to high-volume hospitals had shorter mean critical care stays (56.6 versus 95.6 hours, P<0.001), more critical care procedures (1.9 versus 1.2 per patient, <0.001), and higher resource-intensive weighting (2.8 versus 1.5, P<0.001). No differences in in-hospital mortality (5.5% versus 6.2%, adjusted odds ratio 0.93; 95% CI, 0.61 to 1.41) were observed between high- and low-volume hospitals; however, 30-day cardiovascular readmissions (4.6% versus 6.8%, odds ratio 0.77; 95% CI, 0.60 to 0.99) and cardiovascular emergency-room visits (6.6% versus 9.5%, odds ratio 0.80; 95% CI, 0.69 to 0.94) were lower in high-volume compared to low-volume hospitals. Outcomes stratified by ACS or HF admission diagnosis were similar. Cardiac patients hospitalized in low-volume hospitals were more frequently admitted to critical care units and had longer hospitals stays despite lower resource-intensive weighting. These findings may provide opportunities to standardize critical care utilization for ACS and HF patients across high- and low-volume hospitals. © 2015 The Authors. Published on behalf of the American

  8. Measurements of VOC/SVOC emission factors from burning incenses in an environmental test chamber: influence of temperature, relative humidity, and air exchange rate.

    Science.gov (United States)

    Manoukian, A; Buiron, D; Temime-Roussel, B; Wortham, H; Quivet, E

    2016-04-01

    This study investigates the influence of three environmental indoor parameters (i.e., temperature, relative humidity, and air exchange rate) on the emission of 13 volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) during incense burning. Experiments have been carried out using an environmental test chamber. Statistical results from a classical two-level full factorial design highlight the predominant effect of ventilation on emission factors. The higher the ventilation, the higher the emission factor. Moreover, thanks to these results, an estimation of the concentration range for the compounds under study can be calculated and allows a quick look of indoor pollution induced by incense combustion. Carcinogenic substances (i.e., benzene, benzo(a)pyrene, and formaldehyde) produced from the incense combustion would be predicted in typical living indoors conditions to reach instantaneous concentration levels close to or higher than air quality exposure threshold values.

  9. A Comparison of Amplitude-Based and Phase-Based Positron Emission Tomography Gating Algorithms for Segmentation of Internal Target Volumes of Tumors Subject to Respiratory Motion

    International Nuclear Information System (INIS)

    Jani, Shyam S.; Robinson, Clifford G.; Dahlbom, Magnus; White, Benjamin M.; Thomas, David H.; Gaudio, Sergio; Low, Daniel A.; Lamb, James M.

    2013-01-01

    Purpose: To quantitatively compare the accuracy of tumor volume segmentation in amplitude-based and phase-based respiratory gating algorithms in respiratory-correlated positron emission tomography (PET). Methods and Materials: List-mode fluorodeoxyglucose-PET data was acquired for 10 patients with a total of 12 fluorodeoxyglucose-avid tumors and 9 lymph nodes. Additionally, a phantom experiment was performed in which 4 plastic butyrate spheres with inner diameters ranging from 1 to 4 cm were imaged as they underwent 1-dimensional motion based on 2 measured patient breathing trajectories. PET list-mode data were gated into 8 bins using 2 amplitude-based (equal amplitude bins [A1] and equal counts per bin [A2]) and 2 temporal phase-based gating algorithms. Gated images were segmented using a commercially available gradient-based technique and a fixed 40% threshold of maximum uptake. Internal target volumes (ITVs) were generated by taking the union of all 8 contours per gated image. Segmented phantom ITVs were compared with their respective ground-truth ITVs, defined as the volume subtended by the tumor model positions covering 99% of breathing amplitude. Superior-inferior distances between sphere centroids in the end-inhale and end-exhale phases were also calculated. Results: Tumor ITVs from amplitude-based methods were significantly larger than those from temporal-based techniques (P=.002). For lymph nodes, A2 resulted in ITVs that were significantly larger than either of the temporal-based techniques (P<.0323). A1 produced the largest and most accurate ITVs for spheres with diameters of ≥2 cm (P=.002). No significant difference was shown between algorithms in the 1-cm sphere data set. For phantom spheres, amplitude-based methods recovered an average of 9.5% more motion displacement than temporal-based methods under regular breathing conditions and an average of 45.7% more in the presence of baseline drift (P<.001). Conclusions: Target volumes in images generated

  10. A low-volume polyethylene glycol solution was associated with an increased suboptimal bowel preparation rate but had similar recommendations for an early repeat colonoscopy, procedure times, and adenoma detection rates.

    Directory of Open Access Journals (Sweden)

    Sam C Hankins

    Full Text Available Low-volume polyethylene glycol (PEG bowel preparations are better tolerated by patients than high-volume preparations and may achieve similar preparation quality. However, there is little data comparing their effects on a recommendation for an early repeat colonoscopy (because of a suboptimal preparation, procedure times, adenoma detection rate (ADR, and advanced adenoma detection rate (AADR.This is a retrospective cohort study of outpatient colonoscopies performed during a one-year period at a single academic medical center in which low-volume MoviPrep® (n = 1841 or high-volume Colyte® (n = 1337 was used. All preparations were split-dosed. Appropriate covariates were included in regression models assessing suboptimal preparation quality (fair, poor, or inadequate, procedure times, recommendation for an early repeat colonoscopy, ADR, and AADR.MoviPrep® was associated with an increase in having a suboptimal bowel preparation (OR 1.36; 95% CI: 1.06-1.76, but it was not associated with differences in insertion (p = 0.43, withdrawal (p = 0.22, or total procedure times (p = 0.10. The adjusted percentage with a suboptimal preparation was 11.7% for patients using MoviPrep® and 8.8% for patients using Colyte®. MoviPrep® was not associated with a significant difference in overall ADR (OR 0.93; 95% CI: 0.78-1.11, AADR (OR 1.18; 95% CI: 0.87-1.62, or recommendation for early repeat colonoscopy (OR 1.16; 95% CI: 0.72-1.88.MoviPrep® was associated with a small absolute increase in having a suboptimal preparation, but did not affect recommendations for an early repeat colonoscopy, procedure times, or adenoma detection rates. Mechanisms to reduce financial barriers limiting low-volume preparations should be considered because of their favorable tolerability profile.

  11. Computation of order and volume fill rates for a base stock inventory control system with heterogeneous demand to investigate which customer class gets the best service

    OpenAIRE

    Larsen, Christian

    2006-01-01

    We consider a base stock inventory control system serving two customer classes whose demands are generated by two independent compound renewal processes. We show how to derive order and volume fill rates of each class. Based on assumptions about first order stochastic dominance we prove when one customer class will get the best service. That theoretical result is validated through a series of numerical experiments which also reveal that it is quite robust.

  12. A practical approach to estimate emission rates of indoor air pollutants due to the use of personal combustible products based on small-chamber studies.

    Science.gov (United States)

    Szulejko, Jan E; Kim, Ki-Hyun

    2016-02-01

    As emission rates of airborne pollutants are commonly measured from combusting substances placed inside small chambers, those values need to be re-evaluated for the possible significance under practical conditions. Here, a simple numerical procedure is investigated to extrapolate the chamber-based emission rates of formaldehyde that can be released from various combustible sources including e-cigarettes, conventional cigarettes, or scented candles to their concentration levels in a small room with relatively poor ventilation. This simple procedure relies on a mass balance approach by considering the masses of pollutants emitted from source and lost through ventilation under the assumption that mixing occurs instantaneously in the room without chemical reactions or surface sorption. The results of our study provide valuable insights into re-evaluation procedure of chamber data to allow comparison between extrapolated and recommended values to judge the safe use of various combustible products in confined spaces. If two scented candles with a formaldehyde emission rate of 310 µg h(-1) each were lit for 4 h in a small 20 m(3) room with an air change rate of 0.5 h(-1), then the 4-h (candle lit) and 8-h (up to 8 h after candle lighting) TWA [FA] were determined to be 28.5 and 23.5 ppb, respectively. This is clearly above the 8-h NIOSH recommended exposure limit (REL) time weighted average of 16 ppb. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Solar UV irradiation-induced production of N2O from plant surfaces - low emissions rates but all over the world.

    Science.gov (United States)

    Mikkelsen, T. N.; Bruhn, D.; Ambus, P.

    2016-12-01

    Nitrous oxide (N2O) is an important long-lived greenhouse gas and precursor of stratospheric ozone depleting mono-nitrogen oxides. The atmospheric concentration of N2O is persistently increasing; however, large uncertainties are associated with the distinct source strengths. Here we investigate for the first time N2O emission from terrestrial vegetation in response to natural solar ultra violet radiation. We conducted field site measurements to investigate N2O atmosphere exchange from grass vegetation exposed to solar irradiance with and without UV-screening. Further laboratory tests were conducted with a range of species to study the controls and possible loci of UV-induced N2O emission from plants. Plants released N2O in response to natural sunlight at rates of c. 20-50 nmol m-2 h-1, mostly due to the UV component. The emission rate is temperature dependent with a rather high activation energy indicative for an abiotic process. The prevailing zone for the N2O formation appears to be at the very surface of leaves. However, only c. 26% of the UV-induced N2O appears to originate from plant-N. Further, the process is dependent on atmospheric oxygen concentration. Our work demonstrates that ecosystem emission of the important greenhouse gas, N2O, may be up to c. 30% higher than hitherto assumed.

  14. Nitrous oxide emissions in Midwest US maize production vary widely with band-injected N fertilizer rates, timing and nitrapyrin presence

    International Nuclear Information System (INIS)

    Burzaco, Juan P; Vyn, Tony J; Smith, Doug R

    2013-01-01

    Nitrification inhibitors have the potential to reduce N 2 O emissions from maize fields, but optimal results may depend on deployment of integrated N fertilizer management systems that increase yields achieved per unit of N 2 O lost. A new micro-encapsulated formulation of nitrapyrin for liquid N fertilizers became available to US farmers in 2010. Our research objectives were to (i) assess the impacts of urea–ammonium nitrate (UAN) management practices (timing, rate and nitrification inhibitor) and environmental variables on growing-season N 2 O fluxes and (ii) identify UAN treatment combinations that both reduce N 2 O emissions and optimize maize productivity. Field experiments near West Lafayette, Indiana in 2010 and 2011 examined three N rates (0, 90 and 180 kg N ha −1 ), two timings (pre-emergence and side-dress) and presence or absence of nitrapyrin. Mean cumulative N 2 O–N emissions (Q 10 corrected) were 0.81, 1.83 and 3.52 kg N 2 O–N ha −1 for the rates of 0, 90 and 180 kg N ha −1 , respectively; 1.80 and 2.31 kg N 2 O–N ha −1 for pre-emergence and side-dress timings, respectively; and 1.77 versus 2.34 kg N 2 O–N ha −1 for with and without nitrapyrin, respectively. Yield-scaled N 2 O–N emissions increased with N rates as anticipated (averaging 167, 204 and 328 g N 2 O–N Mg grain −1 for the 0, 90 and 180 kg N ha −1 rates), but were 22% greater with the side-dress timing than the pre-emergence timing (when averaged across N rates and inhibitor treatments) because of environmental conditions following later applications. Overall yield-scaled N 2 O–N emissions were 22% lower with nitrapyrin than without the inhibitor, but these did not interact with N rate or timing. (letter)

  15. Factors affecting accuracy of ventricular volume and ejection fraction measured by gated Tl-201 myocardial perfusion single photon emission computed tomography

    International Nuclear Information System (INIS)

    Pai, Moon Sun; Yang, You Jung; Im, Ki Chun; Hong, Il Ki; Yun, Sung Cheol; Kang, Duk Hyun; Song, Jae Kwan; Moon, Dae Hyuk

    2005-01-01

    Systemic errors in the gated single photon emission computed tomography (SPECT) measurement of left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) may occur. We evaluated whether patient-related factors affected the accuracy of EDV, ESV, and EF measured by electrocardiogram-gated Tl-201 SPECT. A total of 518 patients without perfusion defects on Tl-201 SPECT or coronary artery disease were studied. EDV, ESV, and EF were measured from echocardiography and adenosine stress/redistribution gated Tl-201 SPECT using commercially available software packages (QGS and 4D-MSPECT). We identified factors affecting the accuracy of gated SPECT via multiple linear regression analysis of the differences between echocardiography and gated SPECT. Gated SPECT analyzed with QGS underestimated EDV and ESV, and overestimated EF, but 4D-MSPECT overestimated all those values (p<0.001). Independent variables that increased the difference in EDV between echocardiography and gated SPECT were decreasing LV end-diastolic wall thickness, decreasing body surface area, female sex and increasing EDV (p< 0.001). Those for ESV were decreasing LV end-systolic wall thickness, female sex, and decreasing ESV (p<0.001). Increasing end-systolic wall thickness, male sex and decreasing age were independent determinants associated with an increased difference in EF (p< 0.001). Adenosine stress SPECT showed significantly higher EDV and ESV values and a lower EF than did redistribution SPECT (p< 0.001). In determination of EF, QGS demonstrated a smaller bias than did 4D-MSPECT. However, in men with LV hypertrophy, 4D-MSPECT was superior to QGS. Systemic error by gated Tl-201 SPECT is determined by individual patient-characteristics

  16. Study on the Influence of Velocity, Turbulence Intensity and Temperature on Ammonia Emission Rate in a Wind Tunnel

    DEFF Research Database (Denmark)

    Rong, Li; Nielsen, P V; Zhang, Guo-Qiang

    2009-01-01

    Odor emissions from manure in livestock buildings are an important issue which concerns the human health and air quality as well as animals. Ammonia is one of the most important odors in pig houses. The objective of this paper is to investigate the influence of local velocity, turbulence intensit...

  17. Understanding and Improvement of an Experiment Measuring Chemical Reaction Rates by Monitoring Volume Change of a Gas: On the Reaction between HCl(aq) and Mg(s)

    International Nuclear Information System (INIS)

    Bang, Jeong Ah; Yoon, Hee Sook; Jeong, Dae Hong; Choi, Won Ho

    2006-01-01

    In this study we analyzed and improved an experiment measuring chemical reaction rates introduced in the high school science textbooks through an understanding of the phenomena observed in carrying out the experiment. For this purpose, the contents of textbooks related to the experiment were analyzed, and the problems observed in carrying out the experiment were addressed through experimental analysis. When the experiment was carried out by the method of aquatic transposition presented in textbooks, the observed volume change of H 2 gas was delayed and chemical reaction rate was increased in the early stage of reaction period. To resolve these problems, an improved method for measuring the reaction rates was suggested. In the improved experiment the reaction rate was measured to be constant on time, which was interpreted in terms of the concentration of H + and the surface area of magnesium

  18. Quasi-static method and finite element method for obtaining the modifications of the spontaneous emission rate and energy level shift near a plasmonic nanostructure.

    Science.gov (United States)

    Zhao, Yun-Jin; Tian, Meng; Wang, Xiao-Yun; Yang, Hong; Zhao, Heping; Huang, Yong-Gang

    2018-01-22

    We provide numerical demonstrations of the applicability and accuracy of the quasi-static method and the finite-element method in the investigation of the modifications of the spontaneous emission rate and the energy level shift of an emitter placed near a silver-air interface or a silver nano-sphere. The analytical results are presented as a reference. Our calculations show that the finite element method is an accurate and general method. For frequency away from the radiative mode, the quasi-static method can be applied more effectively for calculating the energy level shift than the spontaneous emission rate. But for frequency around, there is a blue shift for both and this shift increases with the increasing of emitter-silver distance. Applying the theory to the nanosphere dimmer, we see similar phenomenon and find extremely large modifications of the spontaneous emission rate and energy level shift. These findings are instructive in the fields of quantum light-matter interactions.

  19. An effective rate equation approach to reaction kinetics in small volumes: theory and application to biochemical reactions in nonequilibrium steady-state conditions.

    Science.gov (United States)

    Grima, R

    2010-07-21

    Chemical master equations provide a mathematical description of stochastic reaction kinetics in well-mixed conditions. They are a valid description over length scales that are larger than the reactive mean free path and thus describe kinetics in compartments of mesoscopic and macroscopic dimensions. The trajectories of the stochastic chemical processes described by the master equation can be ensemble-averaged to obtain the average number density of chemical species, i.e., the true concentration, at any spatial scale of interest. For macroscopic volumes, the true concentration is very well approximated by the solution of the corresponding deterministic and macroscopic rate equations, i.e., the macroscopic concentration. However, this equivalence breaks down for mesoscopic volumes. These deviations are particularly significant for open systems and cannot be calculated via the Fokker-Planck or linear-noise approximations of the master equation. We utilize the system-size expansion including terms of the order of Omega(-1/2) to derive a set of differential equations whose solution approximates the true concentration as given by the master equation. These equations are valid in any open or closed chemical reaction network and at both the mesoscopic and macroscopic scales. In the limit of large volumes, the effective mesoscopic rate equations become precisely equal to the conventional macroscopic rate equations. We compare the three formalisms of effective mesoscopic rate equations, conventional rate equations, and chemical master equations by applying them to several biochemical reaction systems (homodimeric and heterodimeric protein-protein interactions, series of sequential enzyme reactions, and positive feedback loops) in nonequilibrium steady-state conditions. In all cases, we find that the effective mesoscopic rate equations can predict very well the true concentration of a chemical species. This provides a useful method by which one can quickly determine the

  20. Volume and dose rate dependent (MDR-LDR Ir-192 afterloading interstitial brachytherapy) treatment optimisation, for squamouscell carcinoma of the lip

    International Nuclear Information System (INIS)

    Stas, Nathalie; Goncalves, Julieta; Pinho, Eliana; Trigo, Lurdes; Fernandes, Tome; Vieira, Elio

    1996-01-01

    Introduction: From 1/1/90 to 1/1/95, 53 patients with squamouscell carcinoma of the lip were treated by MDR or LDR Ir-192 afterloading interstitital brachytherapy. We compare the oncological and aesthetical results and sequelae depending on the volume and the dose rate. Material and methods: 53 patients, 41 men and 12 women, median age = 66y; 48 primary tumors (T1 = 26; T2 = 16; T3 = 6; N0 = 47; N1 = 1; M0 = 48) and 5 recurrencies; squamouscell carcinoma (grade 1 =45, g2 =6, g3 =2); clinical extension: buccal comissure=3, check =2, muscular =15, skin =7, lower and upper lip =1. Before radiotherapy, 28 biopsies and 25 excisional surgeries (19 with positive margins, 6 with negative margins) were performed. Brachytherapy was performed alone (dose 60-75 Gy BD85%) or as a boost (dose 10-30 Gy BD85%) associated with external beam (dose 46-50 Gy). MDR or LDR microselectron's afterloading was done after a computerised dosimetry (Paris System): treatment mean time = 30, 98 hours; mean volume = 10,2 cc (T1-T2 8, 61cc); Ir - 192 activity = range 0,7 - 4,792 mCi/cm; reference dose rate 45,6 - 290, 1 cGy/h. Results: 46 patients are alive without cancer, 1 died without responding, 6 died from non oncological diseases; 8 patients had recurrences (5 local, 3 nodal) but are alive. Mean follow-up 30,83 months (range 3-60m), mean DFS = 22,49 m (range 5-57m). Acute secondary effects: 30 radioepithelyties (grade 1 = 7, g2=23, g3=14), and 39 radiomucitis (g1=3; g2=23; g3=13); mean time for complete healing = 21, 66 days. Sequelae: moderate sclerosis of the skin =11, skin retraction = 1, hyperpigmentation2, depigmentation= 10, edema= 6, gingivitis= 7. Aesthetical results: good32; moderate= 18; bad= 2, very bad= 1 (uncontrolled tumor). Conclusions: The sequelae and aesthetical results are closely dependent on the treated volume and the dose rate, less dependent on the total dose, and independent on the Iridium activity. Complete healing time does not influence the late aesthetical results

  1. Soil efflux and total emission rates of magmatic CO2 at the horseshoe lake tree kill, mammoth mountain, California, 1995-1999

    Science.gov (United States)

    Gerlach, T.M.; Doukas, M.P.; McGee, K.A.; Kessler, R.

    2001-01-01

    We report the results of eight soil CO2 efflux surveys by the closed circulation chamber method at the Horseshoe Lake tree kill (HLTK) - the largest tree kill on Mammoth Mountain. The surveys were undertaken from 1995 to 1999 to constrain total HLTK CO2 emissions and to evaluate occasional efflux surveys as a surveillance tool for the tree kills. HLTK effluxes range from 1 to > 10,000 g m -2 day -1 (grams CO2 per square meter per day); they are not normally distributed. Station efflux rates can vary by 7-35% during the course of the 8- to 16-h surveys. Disturbance of the upper 2 cm of ground surface causes effluxes to almost double. Semivariograms of efflux spatial covariance fit exponential or spherical models; they lack nugget effects. Efflux contour maps and total CO2 emission rates based on exponential, spherical, and linear kriging models of survey data are nearly identical; similar results are also obtained with triangulation models, suggesting that the kriging models are not seriously distorted by the lack of normal efflux distributions. In addition, model estimates of total CO2 emission rates are relatively insensitive to the measurement precision of the efflux rates and to the efflux value used to separate magmatic from forest soil sources of CO2. Surveys since 1997 indicate that, contrary to earlier speculations, a termination of elevated CO2 emissions at the HLTK is unlikely anytime soon. The HLTK CO2 efflux anomaly fluctuated greatly in size and intensity throughout the 1995-1999 surveys but maintained a N-S elongation, presumably reflecting fault control of CO2 transport from depth. Total CO2 emission rates also fluctuated greatly, ranging from 46 to 136 t day-1 (metric tons CO2 per day) and averaging 93 t day-1. The large inter-survey variations are caused primarily by external (meteorological) processes operating on time scales of hours to days. The externally caused variations can mask significant changes occurring at depth; a striking example is

  2. Effect of different rates of spent coffee grounds (SCG) on composting process, gaseous emissions and quality of end-product.

    Science.gov (United States)

    Santos, Cátia; Fonseca, João; Aires, Alfredo; Coutinho, João; Trindade, Henrique

    2017-01-01

    The use of spent coffee grounds (SCG) in composting for organic farming is a viable way of valorising these agro-industrial residues. In the present study, four treatments with different amounts of spent coffee grounds (SCG) were established, namely, C 0 (Control), C 10 , C 20 and C 40 , containing 0, 10, 20 and 40% of SCG (DM), respectively; and their effects on the composting process and the end-product quality characteristics were evaluated. The mixtures were completed with Acacia dealbata L. shoots and wheat straw. At different time intervals during composting, carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) emissions were measured and selected physicochemical characteristics of the composts were evaluated. During the composting process, all treatments showed a substantial decrease in total phenolics and total tannins, and an important increase in gallic acid. Emissions of greenhouse gases were very low and no significant difference between the treatments was registered. The results indicated that SCG may be successfully composted in all proportions. However C 40 , was the treatment which combined better conditions of composting, lower GHG emissions and better quality of end product. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Compilation of Published PM2.5 Emission Rates for Cooking, Candles and Incense for Use in Modeling of Exposures in Residences

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Tianchao [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-08-01

    recent analysis of health impacts from air pollutant inhalation in homes found that PM2.5 is the most damaging at the population level. Chronic exposure to elevated PM2.5 has the potential to damage human respiratory systems, and may result in premature death. PM2.5 exposures in homes can be mitigated through various approaches including kitchen exhaust ventilation, filtration, indoor pollutant source reduction and designing ventilation systems to reduce the entry of PM2.5 from outdoors. Analysis of the potential benefits and costs of various approaches can be accomplished using computer codes that simulate the key physical processes including emissions, dilution and ventilation. The largest sources of PM2.5 in residences broadly are entry from outdoors and emissions from indoor combustion. The largest indoor sources are tobacco combustion (smoking), cooking and the burning of candles and incense. Data on the magnitude of PM2.5 and other pollutant emissions from these events and processes are required to conduct simulations for analysis. The goal of this study was to produce a database of pollutant emission rates associated with cooking and the burning of candles and incense. The target use of these data is for indoor air quality modeling.

  4. Does the volume of supplemental intraligamentary injections affect the anaesthetic success rate after a failed primary inferior alveolar nerve block? A randomized-double blind clinical trial.

    Science.gov (United States)

    Aggarwal, V; Singla, M; Miglani, S; Kohli, S; Sharma, V; Bhasin, S S

    2018-01-01

    To investigate the efficacy of 0.2 mL vs. 0.6 mL of 2% lidocaine when given as a supplementary intraligamentary injection after a failed inferior alveolar nerve block (IANB). Ninety-seven adult patients with symptomatic irreversible pulpits received an IANB and root canal treatment was initiated. Pain during treatment was recorded using a visual analogue scale (Heft-Parker VAS). Patients with unsuccessful anaesthesia (n = 78) randomly received intraligamentary injection of either 0.2 mL or 0.6 mL of 2% lidocaine with 1 : 80 000 epinephrine. Root canal treatment was reinitiated. Success after primary injection or supplementary injection was defined as no or mild pain (HP VAS score ≤54 mm) during access preparation and root canal instrumentation. Heart rate was monitored using a finger pulse oximeter. The anaesthetic success rates were analysed with Pearson chi-square test at 5% significance levels. The heart rate changes were analysed using t-tests. The intraligamentary injections with 0.2 mL solution gave an anaesthetic success rate of 64%, whilst the 0.6 mL was successful in 84% of cases with failed primary IANB. (χ 2  = 4.3, P = 0.03). There was no significant effect of the volume of intraligamentary injection on the change in heart rate. Increasing the volume of intraligamentary injection improved the success rates after a failed primary anaesthetic injection. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  5. Electric field effect on the emission rate of H4F and H4S hole traps in InP

    International Nuclear Information System (INIS)

    Darwich, R.; Alek, B.

    2010-01-01

    The electric field effect on the emission rate enhancement of the H4 F and H4 S hole trap in highly Zn-doped InP has been examined using the deep level transient spectroscopy (DLTS) and double correlation DLTS (DDLTS). The DLTS and DDLTS results have been found to be in good agreement for low and intermediate electric fields, but they disagree for large field effect. Comparing our emission data with the theory, we have found that H4 F obeys the quantum model of phonon-assisted tunneling while H4 S follows the Poole-Frenkel model employing a three-dimensional screening coulombic potential. Our results show that the H4 S defect can be attributed to a charged (V p - Zn) complex. (author)

  6. The rate of aucubin, a secondary metabolite in Plantago lanceolata and potential nitrification inhibitor, needed to reduce ruminant urine patch nitrous oxide emissions

    Science.gov (United States)

    Gardiner, C. A.; Clough, T.; Cameron, K.; Di, H.; Edwards, G. R.

    2017-12-01

    Nitrous oxide (N2O) losses derived from grazing ruminant livestock urine patches account for 40% of global N2O emissions. It has been shown that Plantago lanceolata, an herb species used in grazed pastures, contains an active secondary metabolite (aucubin) that has the potential to be excreted by grazing ruminants and inhibit nitrification in the urine patch, a key step in soil N2O production. However, the urinary excretion rate of aucubin needed to significantly reduce urine patch N2O emissions remains unknown. Aucubin was dissolved in bovine urine at three rates (47, 243, and 486 kg ha-1), based on rates used in Dietz et al. (2013) and the calculated highest potential aucubin application rate, from Gardiner et al. (2017). A control, along with a urine treatment and the three aucubin treatments (all urine applied at 700 kg N ha-1), was applied to 20 g soil and incubated in the laboratory for 35 d. Soils were monitored for surface pH, inorganic N concentration (NH4+/NO3-), and gas (N2O and CO2) fluxes. This experiment is currently underway and the results will be presented at the conference. Dietz M, Machill S, Hoffmann H, Schmidtke K 2013. Inhibitory effects of Plantago lanceolata L. on soil N mineralization. Plant and Soil 368: 445-458. Gardiner CA, Clough TJ, Cameron KC, Di HJ, Edwards GR, de Klein CAM 2017. The potential inhibitory effects of Plantago lanceolata and its active secondary metabolite aucubin on soil nitrification and nitrous oxide emissions under ruminant urine patch conditions. Manuscript submitted for publication.

  7. Quantification of Greenhouse Gas Emission Rates from strong Point Sources by Space-borne IPDA Lidar Measurements: Results from a Sensitivity Analysis Study

    Science.gov (United States)

    Ehret, G.; Kiemle, C.; Rapp, M.

    2017-12-01

    The practical implementation of the Paris Agreement (COP21) vastly profit from an independent, reliable and global measurement system of greenhouse gas emissions, in particular of CO2, in order to complement and cross-check national efforts. Most fossil-fuel CO2 emitters emanate from large sources such as cities and power plants. These emissions increase the local CO2 abundance in the atmosphere by 1-10 parts per million (ppm) which is a signal that is significantly larger than the variability from natural sources and sinks over the local source domain. Despite these large signals, they are only sparsely sampled by the ground-based network which calls for satellite measurements. However, none of the existing and forthcoming passive satellite instruments, operating in the NIR spectral domain, can measure CO2 emissions at night time or in low sunlight conditions and in high latitude regions in winter times. The resulting sparse coverage of passive spectrometers is a serious limitation, particularly for the Northern Hemisphere, since these regions exhibit substantial emissions during the winter as well as other times of the year. In contrast, CO2 measurements by an Integrated Path Differential Absorption (IPDA) Lidar are largely immune to these limitations and initial results from airborne application look promising. In this study, we discuss the implication for a space-borne IPDA Lidar system. A Gaussian plume model will be used to simulate the CO2-distribution of large power plants downstream to the source. The space-borne measurements are simulated by applying a simple forward model based on Gaussian error distribution. Besides the sampling frequency, the sampling geometry (e.g. measurement distance to the emitting source) and the error of the measurement itself vastly impact on the flux inversion performance. We will discuss the results by incorporating Gaussian plume and mass budget approaches to quantify the emission rates.

  8. A comparison of lead pollution record in Sphagnum peat with known historical Pb emission rates in the British isles and the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Novak, M.; Erel, Y.; Zemanova, L.; Bottrell, S.H.; Adamova, M. [Czech Geological Survey, Prague (Czech Republic)

    2008-12-15

    Vertical Pb concentration gradients and isotope ratios (Pb-206/Pb-207, Pb-208/Pb-207) are reported for five Pb-210-dated Sphagnum peat profiles. The studied peat bogs are in the British Isles (Thorne Moors, England; Mull, Scotland; and Connemara, Eire) and central Europe (Ocean, northern Czech Republic: Rybarenska slat, southern Czech Republic). Both the U.K. and the Czech Republic experienced maximum Pb emissions from Ag-Pb smelting around 1880. Pb emissions from coal burning peaked in 1955 in the U.K, and in the 1980s in the Czech Republic. In both countries, use of alkyl-lead additives to gasoline resulted in large Pb emissions between 1950 and 2000. We hypothesized that peaks in Pb emissions from smelting, coal burning and gasoline burning, respectively, should be mirrored in the peat profiles. However, a more complicated pattern emerged. Maximum annual Pb accumulation rates occurred in 1870 at Ocean, 1940 at Thorne Moors, 1988 at Rybarenska slat, and 1990 at Mull and Connemara. Atmospheric Pb inputs decreased in the order Thorne Moors {ge} Ocean > Rybarenska slat > Mull > Connemara. The Ocean bog was unique in the central European region in that its maximum Pb pollution dated back to the 19th century and coincided with maximum Pb smelting at Freiberg and Pribram. In contrast, numerous previously studied sites showed no Pb accumulation maximum in the 19th century, but increasing pollution until the 1980s. It remains unclear why Ocean did not record the regional peak in Pb emissions caused by high coal and gasoline burning around 1980, while an array of nearby bogs studied previously did record the 1980 coal/gasoline peak, but no 1880 smelting peak. Mean Pb-206/Pb-207 ratios of potential pollution sources were 1.07 and 1.11 for gasoline, 1.17 and 1.17 for local ores, and 1.18 and 1.19 for coal in the U.K. and the Czech Republic, respectively.

  9. Experimental Study of Effect of EGR Rates on NOx and Smoke Emission of LHR Diesel Engine Fueled with Blends of Diesel and Neem Biodiesel

    Science.gov (United States)

    Modi, Ashishkumar Jashvantlal; Gosai, Dipak Chimangiri; Solanki, Chandresh Maheshchandra

    2018-04-01

    Energy conservation and efficiency have been the quest of engineers concerned with internal combustion engine. Theoretically, if the heat rejected could be reduced, then the thermal efficiency would be improved, at least up to the limit set by the second law of thermodynamics. For current work a ceramic coated twin cylinder water-cooled diesel engine using blends of diesel and Neem biodiesel as fuel was evaluated for its performance and exhaust emissions. Multi cylinder vertical water cooled self-governed diesel engine, piston, top surface of cylinder head and liners were fully coated with partially stabilized zirconia as ceramic material attaining an adiabatic condition. Previous studies have reported that combustion of Neem biodiesel emitted higher NOx, while hydrocarbon and smoke emissions were lower than conventional diesel fuel. Exhaust gas recirculation (EGR) is one of the techniques being used to reduce NOx emission from diesel engines; because it decreases both flame temperature and oxygen concentration in the combustion chamber. The stationary diesel engine was run in laboratory at a high load condition (85% of maximum load), fixed speed (2000 rpm) and various EGR rates of 5-40% (with 5% increment). Various measurements like fuel flow, exhaust temperature, exhaust emission measurement and exhaust smoke test were carried out. The results indicate improved fuel economy and reduced pollution levels for the low heat rejection (LHR) engine. The results showed that, at 5% EGR with TB10, both NOx and smoke opacity were reduced by 26 and 15%, respectively. Furthermore, TB20 along with 10% EGR was also able to reduce both NOx and smoke emission by 34 and 30%, respectively compared to diesel fuel without EGR.

  10. Changes in plasma volume, in transcapillary escape rate of albumin and in subcutaneous blood flow during hypoglycaemia in man

    DEFF Research Database (Denmark)

    Hilsted, J; Bonde-Petersen, F; Madsbad, S

    1985-01-01

    and transcapillary escape rate increased significantly during hypoglycaemia. Skin temperature and local subcutaneous adipose tissue blood flow were measured in four different regions. Both tended to decrease during hypoglycaemia and decreased significantly 2 h after hypoglycaemia. There was no correlation between...... changes in the two measurements, suggesting that there is no simple relationship between subcutaneous blood flow and skin temperature during hypoglycaemia....

  11. The European Dioxin Emission Inventory. Stage II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Quass, U.; Fermann, M.; Broeker, G.

    2001-07-01

    For Stage II of the European Dioxin Project the following objectives were set: - Amendment of existing emission data collected for most relevant emission sources in order to reduce uncertainties of emission estimates. Collecting first emission data from countries not yet performing dioxin emission measurement programs. Extending the inventory of dioxin emissions to ambient air produced in Stage I by a complementary study on emissions to land and water. Extending the regional scope of data collection to countries in Central Europe. The report of Stage II of the European Dioxin Project is presented in 3 Volumes. Volume 1 contains an overview on the background and approach of different activities carried out and on the results obtained. These results are put into a broader view regarding the dioxin reduction measures in Europe leading to conclusions and recommendation for future work. Volume 2 of the report contains a detailed presentation of the sub-projects carried out. The chapters of Volume 2 are structured in a similar manner and start with a short summary in order to allow for a fast cross-reading. In the case of the desk-top studies an overview of the main results or statements is given. Regarding emission measurements details on the experimental set-up and the facilities being investigated are presented. Volume 3 contains a re-evaluation of the dioxin emission inventory presented for the most relevant sources types in the Stage I report. New data gathered from the projects of Stage II as well as from independent activities in the European countries are considered for a revision of the 1995 emission estimates. Additionally, based on current trends and activities the PCDD/F emissions for the years 2000 and 2005 are estimated. Finally, an attempt is made to evaluate the PCDD/F emission reduction rates which might be possible to achieve by the year 2005 compared to 1985. (orig.)

  12. Planning level assessment of greenhouse gas emissions for alternative transportation construction projects : carbon footprint estimator, phase II, volume I - GASCAP model.

    Science.gov (United States)

    2014-03-01

    The GASCAP model was developed to provide a software tool for analysis of the life-cycle GHG : emissions associated with the construction and maintenance of transportation projects. This phase : of development included techniques for estimating emiss...

  13. Enhancement of marine cloud albedo via controlled sea spray injections: a global model study of the influence of emission rates, microphysics and transport

    Directory of Open Access Journals (Sweden)

    H. Korhonen

    2010-05-01

    Full Text Available Modification of cloud albedo by controlled emission of sea spray particles into the atmosphere has been suggested as a possible geoengineering option to slow global warming. Previous global studies have imposed changes in cloud drop concentration in low level clouds to explore the radiative and climatic effects. Here, we use a global aerosol transport model to quantify how an imposed flux of sea spray particles affects the natural aerosol processes, the particle size distribution, and concentrations of cloud drops. We assume that the proposed fleet of vessels emits sea spray particles with a wind speed-dependent flux into four regions of persistent stratocumulus cloud off the western coasts of continents. The model results show that fractional changes in cloud drop number concentration (CDNC vary substantially between the four regions because of differences in wind speed (which affects the spray efficiency of the vessels, transport and particle deposition rates, and because of variations in aerosols from natural and anthropogenic sources. Using spray emission rates comparable to those implied by previous studies we find that the predicted CDNC changes are very small (maximum 20% and in one of the four regions even negative. The weak or negative effect is because the added particles suppress the in-cloud supersaturation and prevent existing aerosol particles from forming cloud drops. A scenario with five times higher emissions (considerably higher than previously assumed increases CDNC on average by 45–163%, but median concentrations are still below the 375 cm−3 assumed in previous studies. An inadvertent effect of the spray emissions is that sulphur dioxide concentrations are suppressed by 1–2% in the seeded regions and sulphuric acid vapour by 64–68% due to chemical reactions on the additional salt particles. The impact of this suppression on existing aerosol is negligible in the model, but should be investigated further in

  14. Measuring and predicting the emission rate of phthalate plasticizer from vinyl flooring in a specially-designed chamber.

    Science.gov (United States)

    Xu, Ying; Liu, Zhe; Park, Jinsoo; Clausen, Per A; Benning, Jennifer L; Little, John C

    2012-11-20

    The emission of di-2-ethylhexyl phthalate (DEHP) from vinyl flooring (VF) was measured in specially designed stainless steel chambers. In duplicate chamber studies, the gas-phase concentration in the chamber increased slowly and reached a steady state level of 0.8-0.9 μg/m(3) after about 20 days. By increasing the area of vinyl flooring and decreasing that of the stainless steel surface within the chamber, the time to reach steady state was significantly reduced, compared to a previous study (1 month versus 5 months). The adsorption isotherm of DEHP on the stainless steel chamber surfaces was explicitly measured using solvent extraction and thermal desorption. The strong partitioning of DEHP onto the stainless steel surface was found to follow a simple linear relationship. Thermal desorption resulted in higher recovery than solvent extraction. Investigation of sorption kinetics showed that it takes several weeks for the sorption of DEHP onto the stainless steel surface to reach equilibrium. The content of DEHP in VF was measured at about 15% (w/w) using pressurized liquid extraction. The independently measured or calculated parameters were used to validate an SVOC emission model, with excellent agreement between model prediction and the observed gas-phase DEHP chamber concentrations.

  15. Characteristics of Biogenic VOCs Emission and its High-Resolution Emission Inventory in China

    Science.gov (United States)

    Li, L.; Li, Y.; Xie, S.

    2017-12-01

    Biogenic volatile organic compounds (BVOCs), with high emission and reactivity, can have substantial impacts on the haze and photochemical pollution. It is essential to establish an accurate high-resolution BVOC emission inventory in China for air quality simulation and decision making. Firstly, a semi-static enclosure technique is developed for the field measurements of BVOC emission rates from 50 plant species in China. Using the GC-MS/FID system, 103 VOC species for each plant species are measured. Based on the field measurements in our study and the reported emission rates at home and abroad, a methodology for determining the emission categories of BVOCs is developed using statistical analysis. The isoprene and monoterpene emission rates of 192 plant species/genera in China are determined based on the above emission categories. Secondly, a new vegetation classification with 82 plant functional types (PFTs) is developed based on the most detailed and latest vegetation investigations, China's official statistical data and Vegetation Atlas of China (1:1,000,000). The leaf biomass is estimated based on provincial vegetation volume and production with biomass-apportion models. The WRF model is used to determine meteorological variables at a high spatio-temporal resolution. Using MEAGNv2.1 and the determined emission rates in our study, the high-resolution emission inventories of isoprene, 37 monoterpene species, 32 sesquiterpene species, and other VOCs (OVOCs) from 82 PFTs in China for 1981-2013 are established. The total annual BVOC emissions in 2013 are 55.88 Tg, including 33.87 Tg isoprene, 6.36 Tg monoterpene, 1.29 Tg sesquiterpene, and 14.37 Tg OVOCs. The distribution of isoprene emission fluxes is consistent with the distribution of broadleaf trees, especially tree species with high or higher emission potential. During 1981-2013, China's BVOC emissions have increased by 47.48% at an average rate of 1.80% yr-1. Emissions of isoprene have the largest enhancement

  16. Taxa de emissão de CO2 de um latossolo fertirrigado com ácido fosfórico por gotejamento CO2 emission rate from a fertigated bare soil with phosphoric acid by dripping

    Directory of Open Access Journals (Sweden)

    José R. Zanini

    2005-04-01

    Full Text Available A aplicação de fertilizantes fosfatados por meio de fertirrigação com sistemas de irrigação localizada pode causar obstrução de emissores. Para evitar esse problema, pode ser utilizado o ácido fosfórico como fonte de fósforo às plantas. Porém, têm sido pouco investigados os efeitos da irrigação relacionados às perdas de CO2 do solo para a atmosfera, em conseqüência da decomposição do carbono orgânico e da infiltração de água no solo. Neste trabalho, investigou-se, no período de um mês, o efeito da fertirrigação com ácido fosfórico nas taxas de emissão de CO2 de um latossolo desprovido de vegetação, na Área Experimental de Irrigação da UNESP, Câmpus de Jaboticabal - SP. Utilizou-se de um sistema de irrigação por gotejamento, com delineamento experimental em blocos casualizados, constando de cinco repetições e cinco tratamentos (0; 30; 60; 90 e 120 kg ha-1de P2O5, aplicados via fertirrigação com ácido fosfórico. Verificou-se que as taxas de emissão de CO2 aumentaram significativamente após as fertirrigações, porém não houve efeito da dose do ácido fosfórico sobre as taxas. A umidade do solo mostrou-se um fator importante na relação entre as variações das taxas de emissão e a temperatura do solo ao longo do período estudado.The application of phosphoric fertilizers through fertigation, with localized irrigation systems, can cause emitters obstruction. In order to avoid this problem, the phosphoric acid can be used as phosphorus source to the plants. However, it has been little investigations on the effects of the irrigation practices, related to the CO2 transference to the atmosphere, due to organic matter decomposition in the soil and its water infiltration. At this work, the rates of emissions of CO2 from a bare soil without vegetation, and fertigated along one month were investigated. The experiment was conducted with randomized blocks design in São Paulo State University - UNESP

  17. High failure rates after (131)I therapy in Graves hyperthyroidism patients with large thyroid volumes, high iodine uptake, and high iodine turnover.

    Science.gov (United States)

    de Jong, Jeroen A F; Verkooijen, Helena M; Valk, Gerlof D; Zelissen, Pierre M J; de Keizer, Bart

    2013-06-01

    The objective of this study was to identify patient characteristics positively and independently associated with I-iodide treatment failure in a large cohort of patients with Graves hyperthyroidism treated with either a calculated "standard" activity of 3.7 MBq/mL (0.1 mCi) or 7.4 MBq/mL (0.2 mCi) of thyroid volume. Data on 385 consecutive patients were prospectively collected. Clinical treatment outcome up to 1 year in relation to thyroid volume, 5- and 24-hour I uptake, 5/24-hour I uptake ratio, and the administered activity of radioiodine were analyzed. Overall treatment results were hypothyroidism in 46%, euthyroidism in 29%, and recurrent hyperthyroidism in 26% of patients. Thyroid volume (P = 0.000), 5/24-hour uptake ratio (P = 0.000), and 5- and 24-hour uptake alone (respectively, P = 0.000 and P = 0.002) were significantly associated with therapy outcome. Patients with a combination of a thyroid volume greater than 50 mL and a 5/24-hour uptake ratio 0.8 or greater showed treatment failure in 70% and 42% (respectively, 3.7 MBq/mL, n = 20; and 7.4 MBq/mL, n = 41).Thyroid volume and 5/24-hour uptake ratio were positively and independently associated with recurrent hyperthyroidism (respectively, odds ratio [OR], 5.3; 95% confidence interval [CI], 2.39-11.76; and OR, 2.97; 95% CI, 1.59-5.59). Higher activities of 7.4 MBq/mL I were associated with a lower risk of treatment failure (OR, 0.34; 95% CI, 0.18-0.62). Large thyroid volumes and high 5/24-hour uptake ratios are positively and independently associated with recurrent hyperthyroidism following I therapy in Graves hyperthyroidism. Higher success rates can be achieved when account is taken of these poor prognostic factors. In consequence, these patients should be treated with activities greater than 7.4 MBq/mL.

  18. Dosimetric Coverage of the Prostate, Normal Tissue Sparing, and Acute Toxicity with High-Dose-Rate Brachytherapy for Large Prostate Volumes

    Directory of Open Access Journals (Sweden)

    George Yang

    2015-06-01

    Full Text Available ABSTRACTPurposeTo evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes.Materials and MethodsOne hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL were treated with high-dose-rate (HDR brachytherapy ± intensity modulated radiation therapy (IMRT to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38% unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE version 4.ResultsMedian follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3% patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17% patients developed Grade 2 acute urinary retention. American Urological Association (AUA symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p=0.04. There was no ≥ Grade 3 acute toxicity.ConclusionsDosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes.

  19. Dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with high-dose-rate brachytherapy for large prostate volumes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, George; Strom, Tobin J.; Shrinath, Kushagra; Mellon, Eric A.; Fernandez, Daniel C.; Biagioli, Matthew C. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Wilder, Richard B., E-mail: mcbiagioli@yahoo.com [Cancer Treatment Centers of America, Newnan, GA (United States)

    2015-05-15

    Purpose: to evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes. Materials and methods: one hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL) were treated with high-dose-rate (HDR) brachytherapy ± intensity modulated radiation therapy (IMRT) to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38%) unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4. Results: median follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3%) patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17%) patients developed Grade 2 acute urinary retention. American Urological Association (AUA) symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p-0.04). There was no ≥ Grade 3 acute toxicity. Conclusions: dosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes. (author)

  20. Experimental investigation of evaporation rate and emission studies of diesel engine fuelled with blends of used vegetable oil biodiesel and producer gas

    Directory of Open Access Journals (Sweden)

    Nanjappan Balakrishnan

    2015-01-01

    Full Text Available An experimental study to measure the evaporation rates, engine performance and emission characteristics of used vegetable oil methyl ester and its blends with producer gas on naturally aspirated vertical single cylinder water cooled four stroke single cylinder diesel engine is presented. The thermo-physical properties of all the bio fuel blends have been measured and presented. Evaporation rates of used vegetable oil methyl ester and its blends have been measured under slow convective environment of air flowing with a constant temperature and the values are compared with fossil diesel. Evaporation constants have been determined by using the droplet regression