Historical variations in the stable isotope composition of mercury in a sediment core from a riverine lake: Effects of dams, pulp and paper mill wastes, and mercury from a chlor-alkali plant

International Nuclear Information System (INIS)

Jackson, Togwell A.

2016-01-01

The Wabigoon River (Ontario, Canada) was affected by dams starting in 1898 and was polluted with pulp and paper mill wastes starting in 1913 and mercury from a chlor-alkali plant from 1962 to 1975. A dated sediment core from a riverine lake was analysed to investigate resultant changes in the biogeochemistry of mercury as revealed by variations in mercury isotope ratios and sediment chemistry. A total mercury maximum formed by the mercury pollution coincided with minimums in the δ-values of the 198 Hg/ 202 Hg, 199 Hg/ 202 Hg, 200 Hg/ 202 Hg, and 201 Hg/ 202 Hg ratios, and the δ-values decreased in the order δ 201 Hg > δ 200 Hg > δ 199 Hg > δ 198 Hg. Thus, mass-dependent fractionation caused depletion in lighter isotopes, implying evaporation of Hg(0) and pollution of the atmosphere as well as the river-lake system. Concurrently, mass-independent fractionation caused 199 Hg enrichment, possibly reflecting an independently documented upsurge in methylmercury production, and 201 Hg depletion, suggesting removal of methylmercury with anomalously high 201 Hg/ 199 Hg ratios by aquatic organisms and accumulation of 201 Hg-depleted inorganic Hg(II) in sediments. The δ 201 Hg/δ 199 Hg ratio rose abruptly when mercury pollution began, reflecting the resultant increase in methylmercury production, and remained high but gradually declined as the pollution abated, paralleling trends shown by methylmercury in aquatic organisms. The δ 201 Hg/δ 199 Hg ratio of pre-1962 background mercury increased ca. 1898 and ca. 1913–1929, suggesting accelerated methylmercury production due to stimulation of microbial activities by the damming of the river and the input of pulp and paper mill wastes, respectively. Other variations were linked to economic and technological factors that affected pulp and paper manufacture. - Highlights: • A core from a lake polluted by Hg and organic wastes was analysed for Hg isotopes. • Hg from a chlor-alkali plant was depleted in lighter

System dynamic analyses on the JKJ mercury target and cold moderator systems

International Nuclear Information System (INIS)

Takahashi, Toshio; Kaminaga, Masanori; Kinoshita, Hidetaka; Aso, Tomokazu; Haga, Katsuhiro; Hino, Ryutaro

2001-01-01

The temperature responses of major points in a mercury target cooling system and in a cold moderator system of JKJ (JAERI/KEK Joint Project) were simulated by the analytical code MATLAB (SIMULINK). As a result, it was made clear that non-control of mercury temperature is the best way to control the mercury target cooling system. If the mercury temperature of the system is controlled by the PID control system using an outlet temperature of heat exchanger, the PID control system shows the characteristics of an on-off control system, and the temperature cannot be controlled. Analytical results also showed that mercury temperature remained below the boiling point of 356degC under 0.1 MPa during a transient at one cooling pump trip. Analytical results for the cold moderator system showed that the outlet temperature of cold moderator vessels could be kept within a temperature range of 1 k during steady-state conditions. (author)

A Distinct Magnetic Isotope Effect Measured in Atmospheric Mercury in Epiphytes

Science.gov (United States)

Ghosh, S.; Odom, A. L.

2007-12-01

Due to the importance of Mercury as an environmental contaminant, mercury cycling in the atmosphere has been extensively studied. However, there still remain uncertainties in the relative amounts of natural and anthropogenic emissions, atmospheric deposition rates as well as the spatial variation of atmospheric mercury. Part of a study to determine the isotopic composition of mercury deposited from the atmosphere has involved the use of epiphytes as monitors. The greatest advantage of such natural monitors is that a widespread, high-density network is possible at low cost. One of the disadvantages at present is that these monitors likely contain different mercury species (for example both gaseous, elemental mercury trapped by adsorption and Hg (II) by wet deposition). The project began with the understanding that biochemical reactions involving metallothioneins within the epiphytes might have produced an isotopic effect. One such regional network was composed of samples of Tillandsia usenoides (common name: Spanish moss) collected along the eastern Coastal Plain of the U.S. from northern Florida to North Carolina. The isotopic composition of a sample is expressed as permil deviations from a standard. The deviations are defined as δAHg = \\left(\\frac{Rsample}{Rstd}-1 \\right)1000 ‰ , where A represents the atomic mass number. R=\\frac{AHg}{202Hg} were measured for the isotopes 198Hg, 199Hg, 200Hg, 201Hg, 202Hg and 204Hg relative to the mercury standard SRM NIST 3133, by a standard-sample bracketing technique. For all samples, the delta values of the even-N plotted against atomic mass numbers define a linear curve. For the odd-N isotopes, δ199Hg and δ201Hg deviate from this mass-dependent fractionation (MDF) relationship and indicate a mass-independent fractionation (MIF) effect and a negative anomaly, i.e. a depletion in 199Hg and 201Hg relative to the even-N isotopes. These deviations are expressed as Δ199Hg = δ199Hgtotal - δ199HgMDF. A Δ201Hg/Δ199Hg

199Hg Moessbauer measurements on mercury, alloys and Hg-fluorides

International Nuclear Information System (INIS)

Wurtinger, W.; Kankeleit, E.

1979-01-01

The Moessbauer effect on the 158 keV 5/2 - -1/2 - transition in 199 Hg, of the order of 10 ppm, has been studied using the current integration technique. The isomer shift between the Hg(I)- and Hg(II)-fluorides as well as the quadrupole splitting in Hg 2 Pt and Hg 2 F 2 are interpreted in terms of relativistic Hartree-Fock-Slater and Molecular Orbital calculations. The following nuclear parameters could be derived: Δ[r 2 ] = (3.2+-1.1) 10 -3 fm 2 and Q(5/2 - ) = (-0.8+-0.4)b. Evidence for an oblate triaxially deformed 199 Hg nucleus is derived from particle plus rotor calculations. (orig.)

Enzymatic Mercury Detoxification: The Regulatory Protein MerR

CERN Multimedia

Ctortecka, B; Walsh, C T; Comess, K M

2002-01-01

Mercury ions and organomercurial reagents are extremely toxic due to their affinity for thiol groups. Many bacteria contain an elaborate detoxification system for a metabolic conversion of toxic Hg$^{2+}$ or organomercurials to less toxic elemental Hg$^0$. The main components of the enzymatic mercury detoxification (see Fig. 1) are the regulatory protein MerR (mercury responsive genetic switch), the organomercurial lyase MerB (cleavage of carbon mercury bonds), and the mercuric ion reductase MerA (reduction of mercuric ions). In these proteins Hg$^{2+}$ is usually coordinated by the thiol groups of cysteines. We utilize the nuclear quadrupole interaction (NQI) of ${\\rm^{199m}}$Hg detected by time differential perturbed angular correlation (TDPAC) to identify the Hg metal site geometries in these proteins in order to elucidate the molecular origin of the ultrasensitivity, selectivity and reaction mechanism of this detoxification system. The short lived TDPAC probe ${\\rm^{199m}}$Hg ($\\tau_{1/2} =$ 43 min) is su...

Cavitation damage prediction for the JSNS mercury target vessel

Energy Technology Data Exchange (ETDEWEB)

Naoe, Takashi, E-mail: naoe.takashi@jaea.go.jp; Kogawa, Hiroyuki; Wakui, Takashi; Haga, Katsuhiro; Teshigawara, Makoto; Kinoshita, Hidetaka; Takada, Hiroshi; Futakawa, Masatoshi

2016-01-15

The liquid mercury target system for the Japan Spallation Neutron Source (JSNS) at the Materials and Life science experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC) is designed to produce pulsed neutrons. The mercury target vessel in this system, which is made of type 316L stainless steel, is damaged by pressure wave-induced cavitation due to proton beam bombardment. Currently, cavitation damage is considered to be the dominant factor influencing the service life of the target vessel rather than radiation damage. In this study, cavitation damage to the interior surface of the target vessel was predicted on the basis of accumulated damage data from off-beam and on-beam experiments. The predicted damage was compared with the damage observed in a used target vessel. Furthermore, the effect of injecting gas microbubbles on cavitation damage was predicted through the measurement of the acoustic vibration of the target vessel. It was shown that the predicted depth of cavitation damage is reasonably coincident with the observed results. Moreover, it was confirmed that the injection of gas microbubbles had an effect on cavitation damage.

Isolation of radioactive thallium from mercury targets

International Nuclear Information System (INIS)

Sevast'yanova, A.S.; Kozlova, M.D.; Malinin, A.B.; Kurenkov, N.V.

1989-01-01

The extraction method of thallium-201, 202, 200 separation from mercury target irradiated by protons is suggested. Tl + in sulfuric acid solution prepared after Hg-target treatment with the sulfuric acid was oxidized up to Tl 3+ with hydrogen peroxide and then it was extracted with butylacetate. Thallium was re-exrtacted by the sulfurous acid solution in the presence of CCl 4 , and Tl 3+ was recovered up to Tl + . The method permits to separate thallium with chemical yield nor less than 95 %. 2 refs

CFD analysis of a liquid mercury target for the National Spallation Neutron Source

International Nuclear Information System (INIS)

Wendel, M.W.; Tov, M.S.

1997-01-01

Computational fluid dynamics (CFD) is being used to analyze the design of the National Spallation Neutron Source (NSNS) target. The target is subjected to the neutronic (internal) heat generation that results from the proton collisions with the mercury nuclei. The liquid mercury simultaneously serves as the neutronic target medium, transports away the heat generated within itself, and cools the metallic target structure. Recirculation and stagnation zones within the target are of particular concern because of the likelihood that they will result in local hot spots. These zones exist because the most feasible target designs include a complete U-turn flow redirection. Although the primary concern is that the target is adequately cooled, the pressure drop from inlet to outlet must also be considered because pressure drop directly affects structural loading and required pumping power. Various design options have been considered in an effort to satisfy these design criteria. Significant improvements to the design have been recommended based on the results. Detailed results are presented for the current target design including a comparison with published pressure-drop data. Comparisons are also made with forced convection heat transfer data for liquid mercury flow in circular tubes

CALCULATIONS FOR A MERCURY JET TARGET IN A SOLENOID MAGNET CAPTURE SYSTEM

International Nuclear Information System (INIS)

GALLARDO, J.; KAHN, S.; PALMER, R.B.; THIEBERGER, P.; WEGGEL, R.J.; MCDONALD, K.

2001-01-01

A mercury jet is being considered as the production target for a muon storage ring facility to produce an intense neutrino beam. A 20 T solenoid magnet that captures pions for muon production surrounds the mercury target. As the liquid metal jet enters or exits the field eddy currents are induced. We calculate the effects that a liquid metal jet experiences in entering and exiting the magnetic field for the magnetic configuration considered in the Neutrino Factory Feasibility Study II

Design study on large-scale mercury loop for engineering test of target of high-intensity proton accelerator

International Nuclear Information System (INIS)

Hino, Ryutaro; Haga, Katsuhiro; Aita, Hideki; Sekita, Kenji; Sudo, Yukio; Koiso, Kohji; Kaminaga, Masanori; Takahashi, Hiromichi.

1997-03-01

A heavy liquid-metal target has been proposed as a representative target of a 5MW-scale neutron source for a neutron scattering facility coupled with a high-intensity proton accelerator. In the report, about mercury considered to be the best material of the heavy liquid-metal target, its properties needed for the design were formulated, and results of research on mercury treatment and of evaluation of heat removal performance on the basis of generating heat obtained by a numerical calculation of a spallation reaction were presented. From these results, a 1.5MW-scale mercury loop which equals to that for the first stage operation of the neutron science program of JAERI was designed conceptually for obtaining design data of the mercury target, and basic flow diagram of the loop and specifications of components were decided: diameter of pipelines flowing mercury at the velocity below 1m/s, power of an electro-magnet pump and structure of a cooler. Through the design, engineering problems were made clear such as selection and development of mercury-resistant materials and optimization of the loop and components for decreasing mercury inventory. (author)

Preparation of 199Tl and its labelled compound

International Nuclear Information System (INIS)

Zhou Dehai; Guan Changtian; Kuang Anren

1991-10-01

Usually, 199 Ti is obtained by the nuclear reaction of 197 Au(α, 2n) 199 Tl. A gold target with 50±0.1 mm in diameter, 0.8 mm in thickness and 99.99% in purity was mounted in a cyclotron beam line. The target was bombarded by α particles with the energy of 25∼27 MeV and the beam current of 15∼20μA. The irradiated gold target was dissolved by aqua regia. Then the saturated aqueous solution of SO 2 was added. The 199 Tl(III)reduced to 199 Tl(I). The deposit of gold was removed. For separation of 199 Tl)I), about 5 mL of raw material solution obtained was transferred to 201 x 8 type anion exchange resin column which had been equilibrated with 4 mol/L HCl. The 199 Tl(I) and Au(III) were desorbed separately with the eluants (90% of aqueous diamide solution,, and 2 mol/L HCL∼5% thiourea) at the flow rate of 0.25 mL/min. After separation, the 10 mL concentrated nitric acid was added to the 199 Tl collected solution to destroy and remove the aqueous diamide solution, then 4 mol/L HCl was added and heated up to remove NO 3 - . The TlCl injection with pH = 5 was made up by using physiological saline. After filtering the 199 TlCl injection was sterilized at 137.3 kPa, 120 deg C about 30 min in an autoclave. The 199 TlCl injection was used in the animal pyrogen, a bacterial, safety, dispensation and myocardial imaging experiments. The good results have been obtained. Now it has undergone clinical experiments

NMR of mercury in porous coal and silica gel

International Nuclear Information System (INIS)

Kasperovich, V.S.; Charnaya, E.V.; Tien, C.; Wur, C.S.

2003-01-01

Temperature dependences of the integral intensity and NMR signals Knight shift in 199 Hg nuclei are measured for liquid and solid mercury introduced into the porous coal and silica gel. The decrease in the crystallization completion temperature and small temperature hysteresis (from 4 up to 9 K) between melting and crystallization are identified. Mercury melting temperature in pores coincided with melting temperature of the bulk mercury. NMR signal from crystalline mercury under conditions of limited geometry was observed for the first time. It is ascertained that Knight shift for mercury in the pores both in liquid and crystalline phases is lesser than for the bulk mercury [ru

THERMODYNAMIC INTERACTION OF THE PRIMARY PROTON BEAM WITH A MERCURY JET TARGET AT A NEUTRINO FACTORY SOURCE

International Nuclear Information System (INIS)

SIMOS, N.; LUDEWIG, H.; KIRK, H.; THIEBERGER, P.; MCDONALD, K.

2001-01-01

This paper addresses the thermodynamic interaction of an intense proton beam with the proposed mercury jet target at a neutrino factory or muon collider source, and the consequences of the generated pressure waves on the target integrity. Specifically, a 24 GeV proton beam with approximately 1.6e13 protons per pulse and a pulse length of 2 nanosec will interact with a 1 cm diameter mercury jet within a 20 Tesla magnetic field. In one option, a train of six such proton pulses is to be delivered on target within 2 microsec, in which case the state of the mercury jet following the interaction with each pulse is critical. Using the equation of state for mercury from the SESAME library, in combination with the energy deposition rates calculated the by the hadron interaction code MARS, the induced 3-D pressure field in the target is estimated. The consequent pressure wave propagation and attenuation in the mercury jet is calculated using an ANSYS code transient analysis, and the state of the mercury jet at the time of arrival of the subsequent pulse is assessed. The amplitude of the pressure wave reaching the nozzle that ejects the mercury jet into the magnetic field is estimated and the potential for mechanical damage is addressed

Mercury isotope fractionation during transfer from post-desulfurized seawater to air.

Science.gov (United States)

Huang, Shuyuan; Lin, Kunning; Yuan, Dongxing; Gao, Yaqin; Sun, Lumin

2016-12-15

Samples of dissolved gaseous mercury (DGM) in the post-desulfurized seawater discharged from a coal-fired power plant together with samples of gaseous elemental mercury (GEM) over the post-desulfurized seawater surface were collected and analyzed to study the mercury isotope fractionation during transfer from post-desulfurized seawater to air. Experimental results showed that when DGM in the seawater was converted to GEM in the air, the δ 202 Hg and Δ 199 Hg values were changed, ranging from -2.98 to -0.04‰ and from -0.31 to 0.64‰, respectively. Aeration played a key role in accelerating the transformation of DGM to GEM, and resulted in light mercury isotopes being more likely to be enriched in the GEM. The ratio Δ 199 Hg/Δ 201 Hg was 1.626 in all samples, suggesting that mercury mass independent fractionation occurred owing to the nuclear volume effect during the transformation. In addition, mass independent fractionation of mercury even isotopes was found in the GEM above the post-desulfurized seawater surface in the aeration pool. Copyright © 2016 Elsevier Ltd. All rights reserved.

Subcellular Targeting of Methylmercury Lyase Enhances Its Specific Activity for Organic Mercury Detoxification in Plants1

Science.gov (United States)

Bizily, Scott P.; Kim, Tehryung; Kandasamy, Muthugapatti K.; Meagher, Richard B.

2003-01-01

Methylmercury is an environmental pollutant that biomagnifies in the aquatic food chain with severe consequences for humans and other animals. In an effort to remove this toxin in situ, we have been engineering plants that express the bacterial mercury resistance enzymes organomercurial lyase MerB and mercuric ion reductase MerA. In vivo kinetics experiments suggest that the diffusion of hydrophobic organic mercury to MerB limits the rate of the coupled reaction with MerA (Bizily et al., 2000). To optimize reaction kinetics for organic mercury compounds, the merB gene was engineered to target MerB for accumulation in the endoplasmic reticulum and for secretion to the cell wall. Plants expressing the targeted MerB proteins and cytoplasmic MerA are highly resistant to organic mercury and degrade organic mercury at 10 to 70 times higher specific activity than plants with the cytoplasmically distributed wild-type MerB enzyme. MerB protein in endoplasmic reticulum-targeted plants appears to accumulate in large vesicular structures that can be visualized in immunolabeled plant cells. These results suggest that the toxic effects of organic mercury are focused in microenvironments of the secretory pathway, that these hydrophobic compartments provide more favorable reaction conditions for MerB activity, and that moderate increases in targeted MerB expression will lead to significant gains in detoxification. In summary, to maximize phytoremediation efficiency of hydrophobic pollutants in plants, it may be beneficial to target enzymes to specific subcellular environments. PMID:12586871

Atomic mass determinations for 183W and 199Hg and the mercury problem

International Nuclear Information System (INIS)

Barillari, D.K.; Vaz, J.V.; Barber, R.C.; Sharma, K.S.

2003-01-01

Recent modifications to the 'Manitoba II' high resolution mass spectrometer are described. Mass differences among the members of the triplet 199 Hg - 183 W 16 O- 12 C 2 35 Cl 5 have been measured. These self-consistent mass differences give masses for 183 W and 199 Hg, as well as the mass difference across the W to Hg region of the mass table. These masses and the mass difference provide important constraints for the least squares atomic mass evaluation

MERIT - The high intensity liquid mercury target experiment at the CERN PS

CERN Document Server

Efthymiopoulos, I

2009-01-01

The MERIT experiment is a proof-of-principle test of a target system for high power proton beams to be used as front-end for a Neutrino Factory complex or a Muon Collider. The experiment took data in autumn 2007 with the fast extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of about 30 × 1012 protons per pulse. The target system, based on a free mercury jet, allowed investigation of the interseption of a 4-MW proton beam inside a 15-T magnetic field required to capture the low-energy secondary pions as the source of the required intense muon beams. Particle detectors have been installed around the target setup to measure the secondary particle flux out of the target and probe cavitation effects in the mercury jet when exited with a beam of variable intensity. With the analysis of the data ongoing, results will be presented here that demonstrate the validity of the liquid target concept.

Optimization study on structural analyses for the J-PARC mercury target vessel

Science.gov (United States)

Guan, Wenhai; Wakai, Eiichi; Naoe, Takashi; Kogawa, Hiroyuki; Wakui, Takashi; Haga, Katsuhiro; Takada, Hiroshi; Futakawa, Masatoshi

2018-06-01

The spallation neutron source at the Japan Proton Accelerator Research Complex (J-PARC) mercury target vessel is used for various materials science studies, work is underway to achieve stable operation at 1 MW. This is very important for enhancing the structural integrity and durability of the target vessel, which is being developed for 1 MW operation. In the present study, to reduce thermal stress and relax stress concentrations more effectively in the existing target vessel in J-PARC, an optimization approach called the Taguchi method (TM) is applied to thermo-mechanical analysis. The ribs and their relative parameters, as well as the thickness of the mercury vessel and shrouds, were selected as important design parameters for this investigation. According to the analytical results of 18 model types designed using the TM, the optimal design was determined. It is characterized by discrete ribs and a thicker vessel wall than the current design. The maximum thermal stresses in the mercury vessel and the outer shroud were reduced by 14% and 15%, respectively. Furthermore, it was indicated that variations in rib width, left/right rib intervals, and shroud thickness could influence the maximum thermal stress performance. It is therefore concluded that the TM was useful for optimizing the structure of the target vessel and to reduce the thermal stress in a small number of calculation cases.

Contribution to the structure study of mercury isotopes with the (p,d) reaction

International Nuclear Information System (INIS)

Grafeuille, S.

1985-10-01

The mercury isotopes were studied by means of the two pick-up reactions (p,d) and (p,t). Enriched targets of 204 Hg, 202 Hg, 201 Hg, 200 Hg, 199 Hg, 198 Hg and 196 Hg were bombarded by a 25 MeV proton beam from the Orsay MP tandem accelerator. Emitted particles were analyzed by a split-pole magnetic spectrometer. We present all the results (nearly 150 states) of the analysis of the (p,d) reactions. Our (p,d) and (p,t) study show new discontinuities around 200 Hg in systematics of mercury isotopes. Part of the results are compared to the U(5) limits of Interacting Bosons (and Fermions) Models. The light nuclei can be considered reasonably described but this could be somewhat fortuitous. (71 refs) [fr

Estimation of thermochemical behavior of spallation products in mercury target

International Nuclear Information System (INIS)

Kobayashi, Kaoru; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Teshigawara, Makoto; Hino, Ryutaro

2002-02-01

In order to examine the radiation safety of a spallation mercury target system, especially source term evaluation, it is necessary to clarify the chemical forms of spallation products generated by spallation reaction with proton beam. As for the chemical forms of spallation products in mercury that involves large amounts of spallation products, these forms were estimated by using the binary phase diagrams and the thermochemical equilibrium calculation based on the amounts of spallation product. Calculation results showed that the mercury would dissolve Al, As, B, Be, Bi, C, Co, Cr, Fe, Ga, Ge, Ir, Mo, Nb, Os, Re, Ru, Sb, Si, Ta, Tc, V and W in the element state, and Ag, Au, Ba, Br, Ca, Cd, Ce, Cl, Cs, Cu, Dy, Er, Eu, F, Gd, Hf, Ho, I, In, K, La, Li, Lu, Mg, Mn, Na, Nd, Ni, O, Pb, Pd, Pr, Pt, Rb, Rh, S, Sc, Se, Sm, Sn, Sr, Tb, Te, Ti, Tl, Tm, Y, Yb, Zn and Zr in the form of inorganic mercury compounds. As for As, Be, Co, Cr, Fe, Ge, Ir, Mo, Nb, Os, Pt, Re, Ru, Se, Ta, V, W and Zr, precipitation could be occurred when increasing the amounts of spallation products with operation time of the spallation target system. On the other hand, beryllium-7 (Be-7), which is produced by spallation reaction of oxygen in the cooling water of a safety hull, becomes the main factor of the external exposure to maintain the cooling loop. Based on the thermochemical equilibrium calculation to Be-H 2 O binary system, the chemical forms of Be in the cooling water were estimated. Then the Be could exist in the form of cations such as BeOH + , BeO + and Be 2+ under the condition of less than 10 -8 of the Be mole fraction in the cooling water. (author)

INTERACTION OF A 24 GeV PROTON BEAM WITH A MUON COLLIDER MERCURY JET TARGET EXPERIMENTAL RESULTS AND THERMODYNAMIC ASSESSMENT

International Nuclear Information System (INIS)

SIMOS, N.; KIRK, H.; FINFROCK, C.; GREENE, G.; LUDEWIG, H.; MCDONALD, K.; MOKHOV, N.

2001-01-01

A muon collider or a neutrino factory based on a muon storage ring require intense beams of muons that can be generated by a 1-4 MW proton beam incident on a moving target inside a 20-T solenoid magnet, with a mercury jet as a preferred example. This paper addresses the thermodynamic interaction of the intense proton beam with the proposed mercury jet target, and the consequences of the generated pressure waves on the target integrity. Specifically, a 24 GeV proton beam with approximately 16 TP (1 TP = 10 12 protons) per pulse and a pulse length of 2 ns will interact with a 1 cm diameter mercury jet within the 20-Tesla magnetic field. In one option, a train of six such proton pulses is to be delivered on target within 2 micros, in which case the state of the mercury jet following the interaction with each pulse is critical. Using the equation of state for mercury from the SESAME library, in combination with the energy deposition rates calculated the by the hadron interaction code MARS, the induced 3-D pressure field in the target is estimated. The consequent pressure wave propagation and attenuation in the mercury jet is calculated using a transient analysis based on finite element modeling, and the state of the mercury jet at the time of arrival of the subsequent pulse is assessed. Issues associated with the use of a liquid metal jet as a target candidate are addressed. Lastly, some experimental results from the BNL E951 experiment are presented and discussed

Mercury flow experiments. 4th report: Measurements of erosion rate caused by mercury flow

International Nuclear Information System (INIS)

Kinoshita, Hidetaka; Kaminaga, Masanori; Haga, Katsuhiro; Hino, Ryutaro

2002-06-01

The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a construction plan of the Material-Life Science Facility, which is consisted of a Muon Science Facility and a Neutron Scattering Facility, in order to open up the new science fields. The Neutron Scattering Facility will be utilized for advanced fields of Material and Life science using high intensity neutron generated by the spallation reaction of a 1 MW pulsed proton beam and mercury target. Design of the spallation mercury target system aims to obtain high neutron performance with high reliability and safety. Since the target system is using mercury as the target material and contains large amount of radioactive spallation products, it is necessary to estimate reliability for strength of instruments in a mercury flow system during lifetime of the facility. Piping and components in the mercury flow system would be damaged by erosion with mercury flow, since these components will be weak by thickness decreasing. This report presents experimental results of wall thickness change by erosion using a mercury experimental loop. In the experiments, an erosion test section and coupons were installed in the mercury experimental loop, and their wall thickness was measured with an ultra sonic thickness gage after every 1000 hours. As a result, under 0.7 m/s of mercury velocity condition which is slightly higher than the practical velocity in mercury pipelines, the erosion is about 3 μm in 1000 hours. The wall thickness decrease during facility lifetime of 30 years is estimated to be less than 0.5 mm. According to the experimental result, it is confirmed that the effect of erosion on component strength is extremely small. Moreover, a measurement of residual mercury on the piping surface was carried out. As a result, 19 g/m 2 was obtained as the residual mercury for the piping surface. According to this result, estimated amount of residual mercury for

Isotopic Fractionation of Mercury in Great Lakes Precipitation

Science.gov (United States)

Gratz, L. E.; Keeler, G. J.; Blum, J. D.; Sherman, L. S.

2009-12-01

Mercury (Hg) is a hazardous bioaccumulative neurotoxin, and atmospheric deposition is a primary way in which mercury enters terrestrial and aquatic ecosystems. However, the chemical processes and transport regimes that mercury undergoes from emission to deposition are not well understood. Thus the use of mercury isotopes to characterize the biogeochemical cycling of mercury is a rapidly growing area of study. Precipitation samples were collected in Chicago, IL, Holland, MI, and Dexter, MI from April 2007 - October 2007 to begin examining the isotopic fractionation of atmospheric mercury in the Great Lakes region. Results show that mass-dependent fractionation relative to NIST-3133 (MDF - δ202Hg) ranged from -0.8‰ to 0.2‰ (±0.2‰) in precipitation samples, while mass-independent fractionation (MIF - Δ199Hg) varied from 0.1‰ to 0.6‰ (±0.1‰). Although clear urban-rural differences were not observed, this may be due to the weekly collection of precipitation samples rather than collection of individual events, making it difficult to truly characterize the meteorology and source influences associated with each sample and suggesting that event-based collection is necessary during future sampling campaigns. Additionally, total vapor phase mercury samples were collected in Dexter, MI in 2009 to examine isotopic fractionation of mercury in ambient air. In ambient samples δ202Hg ranged from 0.3‰ to 0.5‰ (±0.1‰), however Δ199Hg was not significant. Because mercury in precipitation is predominantly Hg2+, while ambient vapor phase mercury is primarily Hg0, these results may suggest the occurrence of MIF during the oxidation of Hg0 to Hg2+ prior to deposition. Furthermore, although it has not been previously reported or predicted, MIF of 200Hg was also detected. Δ200Hg ranged from 0.0‰ to 0.2‰ in precipitation and from -0.1‰ to 0.0‰ in ambient samples. This work resulted in methodological developments in the collection and processing of

Mercury-induced hepatotoxicity in zebrafish: in vivo mechanistic insights from transcriptome analysis, phenotype anchoring and targeted gene expression validation

Directory of Open Access Journals (Sweden)

Mathavan Sinnakaruppan

2010-03-01

Full Text Available Abstract Background Mercury is a prominent environmental contaminant that causes detrimental effects to human health. Although the liver has been known to be a main target organ, there is limited information on in vivo molecular mechanism of mercury-induced toxicity in the liver. By using transcriptome analysis, phenotypic anchoring and validation of targeted gene expression in zebrafish, mercury-induced hepatotoxicity was investigated and a number of perturbed cellular processes were identified and compared with those captured in the in vitro human cell line studies. Results Hepato-transcriptome analysis of mercury-exposed zebrafish revealed that the earliest deregulated genes were associated with electron transport chain, mitochondrial fatty acid beta-oxidation, nuclear receptor signaling and apoptotic pathway, followed by complement system and proteasome pathway, and thereafter DNA damage, hypoxia, Wnt signaling, fatty acid synthesis, gluconeogenesis, cell cycle and motility. Comparative meta-analysis of microarray data between zebrafish liver and human HepG2 cells exposed to mercury identified some common toxicological effects of mercury-induced hepatotoxicity in both models. Histological analyses of liver from mercury-exposed fish revealed morphological changes of liver parenchyma, decreased nucleated cell count, increased lipid vesicles, glycogen and apoptotic bodies, thus providing phenotypic evidence for anchoring of the transcriptome analysis. Validation of targeted gene expression confirmed deregulated gene-pathways from enrichment analysis. Some of these genes responding to low concentrations of mercury may serve as toxicogenomic-based markers for detection and health risk assessment of environmental mercury contaminations. Conclusion Mercury-induced hepatotoxicity was triggered by oxidative stresses, intrinsic apoptotic pathway, deregulation of nuclear receptor and kinase activities including Gsk3 that deregulates Wnt signaling

Massive mercury target for thallium isotope production on the beam of high energy protons

International Nuclear Information System (INIS)

Novgorodov, A.F.; Kolachkovski, A.; Nguen Kong Chang.

1980-01-01

The yields of thallium radioisotopes in a massive mercury target irradiated with 660 MeV protons have been determined. The constancy of isotopic composition of radiothallium along the whole length (40 cm) of the target has been found. The yields of 200 Tl, 201 Tl and 202 Tl amount to 22.9+-2.8; 3.42+-0.45 and 0.459+-0.61 mCu/mkA h, respectively. It has been shown that the extraction of radioisotopes of thallium and some other elements from large amounts of mercury as well as their subsequent concentration may be carried out fully and relatavely fast when using dilute solutions of acetic acid

Rethinking mercury: the role of selenium in the pathophysiology of mercury toxicity.

Science.gov (United States)

Spiller, Henry A

2018-05-01

There is increasing evidence that the pathophysiological target of mercury is in fact selenium, rather than the covalent binding of mercury to sulfur in the body's ubiquitous sulfhydryl groups. The role of selenium in mercury poisoning is multifaceted, bidirectional, and central to understanding the target organ toxicity of mercury. An initial search was performed using Medline/PubMed, Toxline, Google Scholar, and Google for published work on mercury and selenium. These searches yielded 2018 citations. Publications that did not evaluate selenium status or evaluated environmental status (e.g., lake or ocean sediment) were excluded, leaving approximately 500 citations. This initial selection was scrutinized carefully and 117 of the most relevant and representative references were selected for use in this review. Binding of mercury to thiol/sulfhydryl groups: Mercury has a lower affinity for thiol groups and higher affinity for selenium containing groups by several orders of magnitude, allowing for binding in a multifaceted way. The established binding of mercury to thiol moieties appears to primarily involve the transport across membranes, tissue distribution, and enhanced excretion, but does not explain the oxidative stress, calcium dyshomeostasis, or specific organ injury seen with mercury. Effects of mercury on selenium and the role this plays in the pathophysiology of mercury toxicity: Mercury impairs control of intracellular redox homeostasis with subsequent increased intracellular oxidative stress. Recent work has provided convincing evidence that the primary cellular targets are the selenoproteins of the thioredoxin system (thioredoxin reductase 1 and thioredoxin reductase 2) and the glutathione-glutaredoxin system (glutathione peroxidase). Mercury binds to the selenium site on these proteins and permanently inhibits their function, disrupting the intracellular redox environment. A number of other important possible target selenoproteins have been identified

Water flow experiments and analyses on the cross-flow type mercury target model with the flow guide plates

CERN Document Server

Haga, K; Kaminaga, M; Hino, R

2001-01-01

A mercury target is used in the spallation neutron source driven by a high-intensity proton accelerator. In this study, the effectiveness of the cross-flow type mercury target structure was evaluated experimentally and analytically. Prior to the experiment, the mercury flow field and the temperature distribution in the target container were analyzed assuming a proton beam energy and power of 1.5 GeV and 5 MW, respectively, and the feasibility of the cross-flow type target was evaluated. Then the average water flow velocity field in the target mock-up model, which was fabricated from Plexiglass for a water experiment, was measured at room temperature using the PIV technique. Water flow analyses were conducted and the analytical results were compared with the experimental results. The experimental results showed that the cross-flow could be realized in most of the proton beam path area and the analytical result of the water flow velocity field showed good correspondence to the experimental results in the case w...

Estimation of thermochemical behavior of spallation products in mercury target

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Kaoru; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Teshigawara, Makoto; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2002-02-01

In order to examine the radiation safety of a spallation mercury target system, especially source term evaluation, it is necessary to clarify the chemical forms of spallation products generated by spallation reaction with proton beam. As for the chemical forms of spallation products in mercury that involves large amounts of spallation products, these forms were estimated by using the binary phase diagrams and the thermochemical equilibrium calculation based on the amounts of spallation product. Calculation results showed that the mercury would dissolve Al, As, B, Be, Bi, C, Co, Cr, Fe, Ga, Ge, Ir, Mo, Nb, Os, Re, Ru, Sb, Si, Ta, Tc, V and W in the element state, and Ag, Au, Ba, Br, Ca, Cd, Ce, Cl, Cs, Cu, Dy, Er, Eu, F, Gd, Hf, Ho, I, In, K, La, Li, Lu, Mg, Mn, Na, Nd, Ni, O, Pb, Pd, Pr, Pt, Rb, Rh, S, Sc, Se, Sm, Sn, Sr, Tb, Te, Ti, Tl, Tm, Y, Yb, Zn and Zr in the form of inorganic mercury compounds. As for As, Be, Co, Cr, Fe, Ge, Ir, Mo, Nb, Os, Pt, Re, Ru, Se, Ta, V, W and Zr, precipitation could be occurred when increasing the amounts of spallation products with operation time of the spallation target system. On the other hand, beryllium-7 (Be-7), which is produced by spallation reaction of oxygen in the cooling water of a safety hull, becomes the main factor of the external exposure to maintain the cooling loop. Based on the thermochemical equilibrium calculation to Be-H{sub 2}O binary system, the chemical forms of Be in the cooling water were estimated. Then the Be could exist in the form of cations such as BeOH{sup +}, BeO{sup +} and Be{sup 2+} under the condition of less than 10{sup -8} of the Be mole fraction in the cooling water. (author)

Activation calculation of the EURISOL mercury target

Energy Technology Data Exchange (ETDEWEB)

Rapp, B.; David, J.C.; Blideanu, V.; Dore, D.; Ridikas, D.; Thiolliere, N

2006-08-15

We have used MCNPX coupled to CINDER to estimate the production of radioactive nuclides in the EURISOL 4 MW liquid mercury target during a 40 years'lifetime of the installation. The calculations have been done with different intra-nuclear cascade and fission evaporation model combinations. A benchmark exercise has allowed a better understanding of differences seen between these models for the creation of tritium and fission products. To obtain a realistic production yield for tritium gas in proton induced spallation reactions, we recommend using the ISABEL-RAL model, while both CEM2k and BERTINI-RAL overestimate the production rate above 1 GeV incident proton. The best combinations of models to calculate the residual nuclei production are those using ABLA fission-evaporation model, CEM2k or combinations using RAL model are giving too broad mass distributions when compared to available data. An extensive list of radio-nuclides was obtained and is available on tabular format, we show that the 4 nuclei whose contributions to the total activity of the mercury target (after 40 years of irradiation) are the most important are the following: -) 1 day after shutdown: Y{sup 91} (15%), Y{sup 90} (13%), Hg{sup 197} (6%) and Sr{sup 89} (5%); -) 1 year after shutdown: H{sup 3} (19%), Y{sup 90} (17%), Sr{sup 90} (17%) and Nb{sup 93*} (10%); -) 10 years after shutdown: Y{sup 90} (22%), Sr{sup 90} (22%), H{sup 3} (18%) and Nb{sup 93*} (14%); and -) 100 years after shutdown: Mo{sup 93} (34%), Nb{sup 93*} (32%), Pt{sup 193} (9%) and Y{sup 90} (8%). (A.C.)

Developmental Decline in the MicroRNA 199a (miR-199a)/miR-214 Cluster in Human Fetal Lung Promotes Type II Cell Differentiation by Upregulating Key Transcription Factors.

Science.gov (United States)

Mishra, Ritu; Benlhabib, Houda; Guo, Wei; Lerma Cervantes, Connie B; Mendelson, Carole R

2018-06-01

The major surfactant protein, SP-A (a product of the SFTPA gene), serves as a marker of type II pneumocyte differentiation and surfactant synthesis. SFTPA expression in cultured human fetal lung (HFL) epithelial cells is upregulated by hormones that increase cyclic AMP (cAMP) and activate TTF-1/NKX2.1 and NF-κB. To further define mechanisms for type II cell differentiation and induction of SP-A, we investigated roles of microRNAs (miRNAs). Using microarray to identify differentially expressed miRNAs in HFL epithelial cells during type II cell differentiation in culture, we observed that members of the miRNA 199a (miR-199a)/miR-214 cluster were significantly downregulated during differentiation. Validated and predicted targets of miR-199a-3p/miR-199a-5p and miR-214, which serve roles in type II cell differentiation (COX-2, NF-κB p50/p65, and CREB1), and the CREB1 target, C/EBPβ, were coordinately upregulated. Accordingly, overexpression of miR-199a-5p, miR-199a-3p, or miR-214 mimics in cultured HFL epithelial cells decreased COX-2, NF-κB p50/p65, CREB1, and C/EBPβ proteins, with an associated inhibition of SP-A expression. Interestingly, overexpression of the EMT factor, ZEB1, which declines during cAMP-induced type II cell differentiation, increased pri-miR-199a and reduced the expression of the targets NF-κB/p50 and COX-2. Collectively, these findings suggest that the developmental decline in miR-199a/miR-214 in HFL causes increased expression of critical targets that enhance type II cell differentiation and SP-A expression. Copyright © 2018 American Society for Microbiology.

Mercury flow experiments. 4th report Measurements of erosion rate caused by mercury flow

CERN Document Server

Kinoshita, H; Hino, R; Kaminaga, M

2002-01-01

The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a construction plan of the Material-Life Science Facility, which is consisted of a Muon Science Facility and a Neutron Scattering Facility, in order to open up the new science fields. The Neutron Scattering Facility will be utilized for advanced fields of Material and Life science using high intensity neutron generated by the spallation reaction of a 1 MW pulsed proton beam and mercury target. Design of the spallation mercury target system aims to obtain high neutron performance with high reliability and safety. Since the target system is using mercury as the target material and contains large amount of radioactive spallation products, it is necessary to estimate reliability for strength of instruments in a mercury flow system during lifetime of the facility. Piping and components in the mercury flow system would be damaged by erosion with mercury flow, since these components will be we...

Targeted Inhibition of the miR-199a/214 Cluster by CRISPR Interference Augments the Tumor Tropism of Human Induced Pluripotent Stem Cell-Derived Neural Stem Cells under Hypoxic Condition

Directory of Open Access Journals (Sweden)

Yumei Luo

2016-01-01

Full Text Available The human induced pluripotent stem cell (hiPSC provides a breakthrough approach that helps overcoming ethical and allergenic challenges posed in application of neural stem cells (NSCs in targeted cancer gene therapy. However, the tumor-tropic capacity of hiPSC-derived NSCs (hiPS-NSCs still has much room to improve. Here we attempted to promote the tumor tropism of hiPS-NSCs by manipulating the activity of endogenous miR-199a/214 cluster that is involved in regulation of hypoxia-stimulated cell migration. We first developed a baculovirus-delivered CRISPR interference (CRISPRi system that sterically blocked the E-box element in the promoter of the miR-199a/214 cluster with an RNA-guided catalytically dead Cas9 (dCas9. We then applied this CRISPRi system to hiPS-NSCs and successfully suppressed the expression of miR-199a-5p, miR-199a-3p, and miR-214 in the microRNA gene cluster. Meanwhile, the expression levels of their targets related to regulation of hypoxia-stimulated cell migration, such as HIF1A, MET, and MAPK1, were upregulated. Further migration assays demonstrated that the targeted inhibition of the miR-199a/214 cluster significantly enhanced the tumor tropism of hiPS-NSCs both in vitro and in vivo. These findings suggest a novel application of CRISPRi in NSC-based tumor-targeted gene therapy.

The Merit(nTOF-11) High Intensity Liquid Mercury Target Experiment at the CERN PS

CERN Document Server

Efthymiopoulos, I; Caretta, O; Carroll, A J; Fabich, A; Graves, V B; Grudiev, A; Haug, F; Kirk, H G; Lettry, Jacques; Loveridge, P; McDonald, K T; Mokhov, N; Palm, M; Park, H; Pernegger, H; Spampinato, P T; Steerenberg, R; Striganov, S; Tsang, T

2008-01-01

The MERIT(nTOF-11) experiment is a proof-ofprinciple test of a target system for a high power proton beam to be used as front-end for a neutrino factory or a muon collider. The experiment took data in autumn 2007 with the fast-extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of $30 × 10^{12}$ per pulse. The target system, based on a free mercury jet, is capable of intercepting a 4-MW proton beam inside a 15-T magnetic field required to capture the low energy secondary pions as the source for intense muon beams. Partice detectors installed around the target setup measure the secondary particle flux out of the target and can probe cavitation effects in the mercury jet when excited by an intense proton beam.Preliminary results of the data analysis will be presented here.

Preparation of 199Tl radionuclide on U-120 (R-7M) cyclotron

International Nuclear Information System (INIS)

Glukhov, G.G.; Komov, A.I.; Maslennikov, Yu.S.; Malinin, A.B.; Skuridin, V.S.

1989-01-01

The possibility of preparation of 199 Tl radionuclide, which can be successfully used instead of thallium-201 in radiopharmaceutical compound for medicine diagnosis due to nuclear-physical characteristics, is studied. It is established that thallium-199 free from thallium-298, but with thallium-200 impurity, is formed under irradiation of gold-197 target by 27.2-28 MeV energy α-particles. The construction of a thin-layer gold target allowing to decrease thallium-200 impurity up to >0.5 % is developed and tested. Perspectivity of thallium-199 production at domestic cyclotrons P-7M and u-120 is shown. 4 refs.; 2 figs.; 3 tabs

Optical diagnostics of mercury jet for an intense proton target.

Science.gov (United States)

Park, H; Tsang, T; Kirk, H G; Ladeinde, F; Graves, V B; Spampinato, P T; Carroll, A J; Titus, P H; McDonald, K T

2008-04-01

An optical diagnostic system is designed and constructed for imaging a free mercury jet interacting with a high intensity proton beam in a pulsed high-field solenoid magnet. The optical imaging system employs a backilluminated, laser shadow photography technique. Object illumination and image capture are transmitted through radiation-hard multimode optical fibers and flexible coherent imaging fibers. A retroreflected illumination design allows the entire passive imaging system to fit inside the bore of the solenoid magnet. A sequence of synchronized short laser light pulses are used to freeze the transient events, and the images are recorded by several high speed charge coupled devices. Quantitative and qualitative data analysis using image processing based on probability approach is described. The characteristics of free mercury jet as a high power target for beam-jet interaction at various levels of the magnetic induction field is reported in this paper.

Measurements of activation reaction rate distributions on a mercury target bombarded with high-energy protons at AGS

International Nuclear Information System (INIS)

Takada, Hiroshi; Kasugai, Yoshimi; Nakashima, Hiroshi; Ikeda, Yujiro; Jerde, Eric; Glasgow, David

2000-02-01

A neutronics experiment was carried out using a thick mercury target at the Alternating Gradient Synchrotron (AGS) facility of Brookhaven National Laboratory in a framework of the ASTE (AGS Spallation Target Experiment) collaboration. Reaction rate distributions around the target were measured by the activation technique at incident proton energies of 1.6, 12 and 24 GeV. Various activation detectors such as the 115 In(n,n') 115m In, 93 Nb(n,2n) 92m Nb, and 209 Bi(n,xn) reactions with threshold energies ranging from 0.3 to 70.5 MeV were employed to obtain the reaction rate data for estimating spallation source neutron characteristics of the mercury target. It was found from the measured 115 In(n,n') 115m In reaction rate distribution that the number of leakage neutrons becomes maximum at about 11 cm from the top of hemisphere of the mercury target for the 1.6-GeV proton incidence and the peak position moves towards forward direction with increase of the incident proton energy. The similar result was observed in the reaction rate distributions of other activation detectors. The experimental procedures and a full set of experimental data in numerical form are summarized in this report. (author)

EURISOL MERCURY TARGET EXPERIMENT: CERN SAFETY REPORT

CERN Document Server

J. Gulley (CERN SC/GS)

Report on a visit to the mercury-handling lab at IPUL. The aim was to provide recommendations to IPUL on general health and safety issues relatring to the handling of mercury, the objective being to reduce exposure to acceptable levels, so far as is reasonably practical.

Measurements of activation reaction rate distributions on a mercury target bombarded with high-energy protons at AGS

Energy Technology Data Exchange (ETDEWEB)

Takada, Hiroshi; Kasugai, Yoshimi; Nakashima, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ino, Takashi; Kawai, Masayoshi [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan); Jerde, Eric; Glasgow, David [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

2000-02-01

A neutronics experiment was carried out using a thick mercury target at the Alternating Gradient Synchrotron (AGS) facility of Brookhaven National Laboratory in a framework of the ASTE (AGS Spallation Target Experiment) collaboration. Reaction rate distributions around the target were measured by the activation technique at incident proton energies of 1.6, 12 and 24 GeV. Various activation detectors such as the {sup 115}In(n,n'){sup 115m}In, {sup 93}Nb(n,2n){sup 92m}Nb, and {sup 209}Bi(n,xn) reactions with threshold energies ranging from 0.3 to 70.5 MeV were employed to obtain the reaction rate data for estimating spallation source neutron characteristics of the mercury target. It was found from the measured {sup 115}In(n,n'){sup 115m}In reaction rate distribution that the number of leakage neutrons becomes maximum at about 11 cm from the top of hemisphere of the mercury target for the 1.6-GeV proton incidence and the peak position moves towards forward direction with increase of the incident proton energy. The similar result was observed in the reaction rate distributions of other activation detectors. The experimental procedures and a full set of experimental data in numerical form are summarized in this report. (author)

High Power Proton Beam Shocks and Magnetohydrodynamics in a Mercury Jet Target for a Neutrino Factory

CERN Document Server

Fabich, A; Fabjan, Christian

2002-01-01

The feasibility of liquid metal jet targets for secondary particle production with high power proton beams has been studied. The main aspects of the thesis were benchmark experiments covering the behaviour of liquid targets under thermal shock waves induced by high power proton beams, and also magnetohydrodynamic effects. Severe challenges were imposed by safety issues and the restricted beam time to the tests in ISOLDE at CERN and at the High Magnetic Field Laboratory at Grenoble. Restricted access times in high radiation level areas were of the order of minutes and in this short time span, the complete experimental setup had to be performed and verified. The involvement of mercury as liquid target material and its activation during beam tests demanded special confinement precautions. The setup for both experiments was based on the use of a high speed camera system for observation of the mercury target. The presence of high radiation or high magnetic field required the installation of the sensitive camera sy...

Water flow experiment using the PIV technique and the thermal hydraulic analysis on the cross-flow type mercury target model

International Nuclear Information System (INIS)

Haga, Katsuhiro; Terada, Atsuhiko; Kaminaga, Masanori; Hino, Ryutaro

2001-01-01

In this study the effectiveness of the cross-flow type mercury target structure was evaluated experimentally and analytically. The average water flow velocity field in the target mock-up model, which was fabricated with plexiglass, was measured at room temperature using the PIV (Particle Image Velocimetry) technique. The water flow analyses were conducted and the analytical results were compared with the experimental results. The experimental results showed that the cross-flow could be realized in the former part of the proton beam path where the heat load by the spallation reaction is large, and the analytical result of the water flow velocity field showed good correspondence to the experimental result in the case of the Reynolds number of more than 4.83 x 10 5 at the model inlet. With these results, the effectiveness of the cross-flow type mercury target structure and the present analysis code system was demonstrated. Then the mercury flow field and the temperature distribution in the target container were analyzed assuming the proton beam energy and power of 3 GeV and 5 MW. The analytical result showed that the cross-flow field of mercury, which is similar to the water flow field, could also be attained. (author)

Role of microRNA-199a-5p and discoidin domain receptor 1 in human hepatocellular carcinoma invasion

Directory of Open Access Journals (Sweden)

Shen Qingli

2010-08-01

Full Text Available Abstract Background Micro-ribonucleic acid (miRNA-199a-5p has been reported to be decreased in hepatocellular carcinoma (HCC compared to normal tissue. Discoidin domain receptor-1 (DDR1 tyrosine kinase, involved in cell invasion-related signaling pathway, was predicted to be a potential target of miR-199a-5p by the use of miRNA target prediction algorithms. The aim of this study was to investigate the role of miR-199a-5p and DDR1 in HCC invasion. Methods Mature miR-199a-5p and DDR1 expression were evaluated in tumor and adjacent non-tumor liver tissues from 23 patients with HCC undergoing liver resection and five hepatoma cell lines by the use of real-time quantitative RT-PCR (qRT-PCR analysis. The effect of aberrant miR-199a-5p expression on cell invasion was assessed in vitro using HepG2 and SNU-182 hepatoma cell lines. Luciferase reporter assay was employed to validate DDR1 as a putative miR-199a-5p target gene. Regulation of DDR1 expression by miR-199a-5p was assessed by the use qRT-PCR and western blotting analysis. Results A significant down-regulation of miR-199a-5p was observed in 65.2% of HCC tissues and in four of five cell lines. In contrast, DDR1 expression was significantly increased in 52.2% of HCC samples and in two of five cell lines. Increased DDR1 expression in HCC was associated with advanced tumor stage. DDR1 was shown to be a direct target of miR-199a-5p by luciferase reporter assay. Transfection of miR-199a-5p inhibited invasion of HepG2 but not SNU-182 hepatoma cells. Conclusions Decreased expression of miR-199a-5p contributes to increased cell invasion by functional deregulation of DDR1 activity in HCC. However, the effect of miR-199a-5p on DDR1 varies among individuals and hepatoma cell lines. These findings may have significant translational relevance for development of new targeted therapies as well as prognostic prediction for patients with HCC.

Double spike with isotope pattern deconvolution for mercury speciation

International Nuclear Information System (INIS)

Castillo, A.; Rodriguez-Gonzalez, P.; Centineo, G.; Roig-Navarro, A.F.; Garcia Alonso, J.I.

2009-01-01

Full text: A double-spiking approach, based on an isotope pattern deconvolution numerical methodology, has been developed and applied for the accurate and simultaneous determination of inorganic mercury (IHg) and methylmercury (MeHg). Isotopically enriched mercury species ( 199 IHg and 201 MeHg) are added before sample preparation to quantify the extent of methylation and demethylation processes. Focused microwave digestion was evaluated to perform the quantitative extraction of such compounds from solid matrices of environmental interest. Satisfactory results were obtained in different certificated reference materials (dogfish liver DOLT-4 and tuna fish CRM-464) both by using GC-ICPMS and GC-MS, demonstrating the suitability of the proposed analytical method. (author)

Measurement of induced radioactivity in a spallation neutron field of a mercury target for GeV-proton bombardment

International Nuclear Information System (INIS)

Kasugai, Y.; Takada, H.; Nakashima, H.

2001-01-01

An integral experiment on radioactivity induced in spallation neutron fields was carried out under the ASTE (AGS-Spallation Target Experiment) collaboration using AGS (Alternative Gradient Synchrotron) at BNL (Brookhaven National Laboratory). The spallation neutrons were produced by bombarding a mercury target with protons of 1.6, 12 and 24 GeV. The number of protons was 3 - 4 x 10 13 for each irradiation. The irradiated materials were titanium, nickel, cobalt, yttrium, and bismuth, and placed on the cylindrical surface of the mercury target at the distance of 15 - 16 cm from the beam-incident-surface of the target. Disintegration rates of induced radioactivities were measured at several cooling-time ranging from hours to months. The principal nuclides contributing to the radioactivity were pointed out for each material. The experimental results for bismuth were compared with the calculations with DCAHIN-SP code. (author)

Mercury purification in the megawatt liquid metal spallation target of EURISOL-DS

CERN Document Server

Neuhausen, Joerg; Eller, Martin; Schumann, Dorothea; Eichler, Bernd; Horn, Susanne

High power spallation targets are going to be used extensively in future research and technical facilities such as spallation neutron sources, neutrino factories, radioactive beam facilities or accelerator driven systems for the transmutation of long-lived nuclear waste. Within EURISOL-DS, a 4 MW liquid metal spallation target is designed to provide neutrons for a fission target, where neutron rich radionuclides will be produced. For the spallation target, mercury is planned to be used as target material. A large amount of radionuclides ranging from atomic number Z=1 to 81 will be produced in the liquid metal during long term irradiation. It is planned to remove those radionuclides by chemical or physicochemical methods to reduce its radioactivity. For the development of a purification procedure, knowledge about the chemical state of the different elements present in the mixture is required. We present a general concept of applicable separation techniques in a target system and show some results of experiment...

Measurement of induced radioactivity in a spallation neutron field of a mercury target for GeV-proton bombardment

Energy Technology Data Exchange (ETDEWEB)

Kasugai, Y.; Takada, H.; Nakashima, H. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

2001-03-01

An integral experiment on radioactivity induced in spallation neutron fields was carried out under the ASTE (AGS-Spallation Target Experiment) collaboration using AGS (Alternative Gradient Synchrotron) at BNL (Brookhaven National Laboratory). The spallation neutrons were produced by bombarding a mercury target with protons of 1.6, 12 and 24 GeV. The number of protons was 3 - 4 x 10{sup 13} for each irradiation. The irradiated materials were titanium, nickel, cobalt, yttrium, and bismuth, and placed on the cylindrical surface of the mercury target at the distance of 15 - 16 cm from the beam-incident-surface of the target. Disintegration rates of induced radioactivities were measured at several cooling-time ranging from hours to months. The principal nuclides contributing to the radioactivity were pointed out for each material. The experimental results for bismuth were compared with the calculations with DCAHIN-SP code. (author)

Chemical Form Matters: Differential Accumulation of Mercury Following Inorganic and Organic Mercury Exposures in Zebrafish Larvae

Energy Technology Data Exchange (ETDEWEB)

Korbas, Malgorzata; MacDonald, Tracy C.; Pickering, Ingrid J.; George, Graham N.; Krone, Patrick H. (Saskatchewan)

2013-04-08

Mercury, one of the most toxic elements, exists in various chemical forms each with different toxicities and health implications. Some methylated mercury forms, one of which exists in fish and other seafood products, pose a potential threat, especially during embryonic and early postnatal development. Despite global concerns, little is known about the mechanisms underlying transport and toxicity of different mercury species. To investigate the impact of different mercury chemical forms on vertebrate development, we have successfully combined the zebrafish, a well-established developmental biology model system, with synchrotron-based X-ray fluorescence imaging. Our work revealed substantial differences in tissue-specific accumulation patterns of mercury in zebrafish larvae exposed to four different mercury formulations in water. Methylmercury species not only resulted in overall higher mercury burdens but also targeted different cells and tissues than their inorganic counterparts, thus revealing a significant role of speciation in cellular and molecular targeting and mercury sequestration. For methylmercury species, the highest mercury concentrations were in the eye lens epithelial cells, independent of the formulation ligand (chloride versus L-cysteine). For inorganic mercury species, in absence of L-cysteine, the olfactory epithelium and kidney accumulated the greatest amounts of mercury. However, with L-cysteine present in the treatment solution, mercuric bis-L-cysteineate species dominated the treatment, significantly decreasing uptake. Our results clearly demonstrate that the common differentiation between organic and inorganic mercury is not sufficient to determine the toxicity of various mercury species.

[Regulation of microRNA-199a on adhesion, migration and invasion ability of human endometrial stromal cells].

Science.gov (United States)

Dai, Lan; Gu, Li-ying; Zhu, Jie; Shi, Jun; Wang, Yao; Ji, Fang; Di, Wen

2011-11-01

To study the regulation of microRNA 199a (miR-199a) on adhesion, migration and invasion ability of human eutopic endometrial stromal cells (ESC) from patients with endometriosis. ESC were transfected with miR-199a mimics or negative control (NC) RNA by lipofectamine 2000. The adhesion, migration and invasion ability of ESC were detected by cell adhesion assay, scratch assay, cell migration assay and matrigel invasion assay, respectively. Luciferase reporter assay was used to evaluate whether IKKβ was the target gene of miR-199a. The expression of ikappa B kinase beta (IKKβ), inhibitory kappa B alpha (IκB-α), phospho-IκB-α(p-IκB-α) and nuclear factor-kappa B (NF-κB) protein were measured by western blot. (1) Adhesion potential: the adhesion inhibitory rates were (14 ± 4)% in miR-199a group and 0 in control group, which showed significant difference (P scratch assay, ESC transfected with miR-199a exhibited a lower scratch closure rate than that of controls. In migration and invasion assays, the migration and invasion ability of miR-199a group were significantly decreased compared with those of NC group [130 ± 31 vs. 247 ± 36 (P < 0.01); 63 ± 15 vs. 133 ± 17 (P < 0.01), respectively]. (3) The luciferase activity of miR-199a group was significantly lowered than that of control group [0.160 ± 0.006 vs. 0.383 ± 0.083 (P < 0.01)]. The protein levels of IKKβ, p-IκB-α, IκB-α and NF-κB of 0.350 ± 0.195, 0.443 ± 0.076, 1.970 ± 0.486 and 0.454 ± 0.147 in miR-199a group were significantly different compared with the NC group in which the protein levels were set at 1.000 (P < 0.01). miR-199a can inhibit the adhesion, migration and invasion of the ESC. IKKβ is the target gene of miR-199a in ESC. One of the mechanisms of the inhibition effect is probably that miR-199a inhibits the activation of NF-κB signaling pathway by targeting IKKβ gene.

30 CFR 19.9 - Performance.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Performance. 19.9 Section 19.9 Mineral... MINING PRODUCTS ELECTRIC CAP LAMPS § 19.9 Performance. In addition to the general design and the safety... respect to performance, as follows: (a) Time of burning and candlepower. Permissible electric cap lamps...

46 CFR 199.202 - Rescue boats.

Science.gov (United States)

2010-10-01

... SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Passenger Vessels § 199.202 Rescue boats... 46 Shipping 7 2010-10-01 2010-10-01 false Rescue boats. 199.202 Section 199.202 Shipping COAST... least one rescue boat approved under approval series 160.156 that is equipped as specified in table 199...

Use of new threshold detector 199Hg(n,n')/sup 199m/Hg for neutron spectrum unfolding

International Nuclear Information System (INIS)

Sakurai, K.

1982-01-01

The nuclear data for the 199 Hg(n,n')/sup 199m/Hg reaction are reviewed and the data are used for neutron spectrum unfolding. The neutron spectrum of the YAYOI glory-hole is unfolded by SAND II with 10 nuclear reactions including the 199 Hg(n,n')/sup 199m/Hg reaction. The ratio of the measured reaction rate to the calculated reaction rate is about 1:1.1 for the guess spectrum. The 199 Hg(n,n')/sup 199m/Hg, 115 In(n,n')/sup 115m/In, 103 Rh(n,n')/sup 103m/Rh reactions should be useful threshold detectors for the neutron dosimetry with low level fast neutron flux

Microrna-199a-5p Functions as a Tumor Suppressor via Suppressing Connective Tissue Growth Factor (CTGF) in Follicular Thyroid Carcinoma.

Science.gov (United States)

Sun, Dawei; Han, Shen; Liu, Chao; Zhou, Rui; Sun, Weihai; Zhang, Zhijun; Qu, Jianjun

2016-04-11

BACKGROUND The objective of this study was to explore the role of miR-199a-5p in the development of thyroid cancer, including its anti-proliferation effect and downstream signaling pathway. MATERIAL AND METHODS We conducted qRT-PCR analysis to detect the expressions of several microRNAs in 42 follicular thyroid carcinoma patients and 42 controls. We identified CTGF as target of miR-491, and viability and cell cycle status were determined in FTC-133 cells transfected with CTGF siRNA, miR-199a mimics, or inhibitors. RESULTS We identified an underexpression of miR-199a-5p in follicular thyroid carcinoma tissue samples compared with controls. Then we confirmed CTGF as a target of miR-199a-5p thyroid cells by using informatics analysis and luciferase reporter assay. Additionally, we found that mRNA and protein expression levels of CTGF were both clearly higher in malignant tissues than in benign tissues. miR-199a-5p mimics and CTGF siRNA similarly downregulated the expression of CTGF, and reduced the viability of FTC-133 cells by arresting the cell cycle in G0 phase. Transfection of miR-199a-5p inhibitors increased the expression of CTGF and promoted the viability of the cells by increasing the fraction of cells in G2/M and S phases. CONCLUSIONS Our study proves that the CTGF gene is a target of miR-199a-5p, demonstrating the negatively related association between CTGF and miR-199a. These findings suggest that miR-199a-5p might be a novel therapeutic target in the treatment of follicular thyroid carcinoma.

miR-199a-3p displays tumor suppressor functions in papillary thyroid carcinoma.

Science.gov (United States)

Minna, Emanuela; Romeo, Paola; De Cecco, Loris; Dugo, Matteo; Cassinelli, Giuliana; Pilotti, Silvana; Degl'Innocenti, Debora; Lanzi, Cinzia; Casalini, Patrizia; Pierotti, Marco A; Greco, Angela; Borrello, Maria Grazia

2014-05-15

Thyroid cancer incidence is rapidly increasing. Papillary Thyroid Carcinoma (PTC), the most frequent hystotype, usually displays good prognosis, but no effective therapeutic options are available for the fraction of progressive PTC patients. BRAF and RET/PTC are the most frequent driving genetic lesions identified in PTC. We developed two complementary in vitro models based on RET/PTC1 oncogene, starting from the hypothesis that miRNAs modulated by a driving PTC-oncogene are likely to have a role in thyroid neoplastic processes. Through this strategy, we identified a panel of deregulated miRNAs. Among these we focused on miR-199a-3p and showed its under-expression in PTC specimens and cell lines. We demonstrated that miR-199a-3p restoration in PTC cells reduces MET and mTOR protein levels, impairs migration and proliferation and, more interesting, induces lethality through an unusual form of cell death similar to methuosis, caused by macropinocytosis dysregulation. Silencing MET or mTOR, both involved in survival pathways, does not recapitulate miR-199a-3p-induced cell lethality, thus suggesting that the cooperative regulation of multiple gene targets is necessary. Integrated analysis of miR-199a-3p targets unveils interesting networks including HGF and macropinocytosis pathways. Overall our results indicate miR-199a-3p as a tumor suppressor miRNA in PTC.

Mercury isotope constraints on the source for sediment-hosted lead-zinc deposits in the Changdu area, southwestern China

Science.gov (United States)

Xu, Chunxia; Yin, Runsheng; Peng, Jiantang; Hurley, James P.; Lepak, Ryan F.; Gao, Jianfeng; Feng, Xinbin; Hu, Ruizhong; Bi, Xianwu

2018-03-01

The Lanuoma and Cuona sediment-hosted Pb-Zn deposits hosted by Upper Triassic limestone and sandstone, respectively, are located in the Changdu area, SW China. Mercury concentrations and Hg isotopic compositions from sulfide minerals and potential source rocks (e.g., the host sedimentary rocks and the metamorphic basement) were investigated to constrain metal sources and mineralization processes. In both deposits, sulfide minerals have higher mercury (Hg) concentrations (0.35 to 1185 ppm) than the metamorphic basement rocks (0.05 to 0.15 ppm) and sedimentary rocks (0.02 to 0.08 ppm). Large variations of mass-dependent fractionation (3.3‰ in δ202Hg) and mass-independent fractionation (0.3‰ in Δ199Hg) of Hg isotopes were observed. Sulfide minerals have Hg isotope signatures that are similar to the hydrothermal altered rocks around the deposit, and similar to the metamorphic basement, but different from barren sedimentary rocks. The variation of Δ199Hg suggests that Hg in sulfides was mainly derived from the underlying metamorphic basement. Mercury isotopes could be a geochemical tracer in understanding metal sources in hydrothermal ore deposits.

Martensitic/ferritic steels as container materials for liquid mercury target of ESS

International Nuclear Information System (INIS)

Dai, Y.

1996-01-01

In the previous report, the suitability of steels as the ESS liquid mercury target container material was discussed on the basis of the existing database on conventional austenitic and martensitic/ferritic steels, especially on their representatives, solution annealed 316 stainless steel (SA 316) and Sandvik HT-9 martensitic steel (HT-9). Compared to solution annealed austenitic stainless steels, martensitic/ferritic steels have superior properties in terms of strength, thermal conductivity, thermal expansion, mercury corrosion resistance, void swelling and irradiation creep resistance. The main limitation for conventional martensitic/ferritic steels (CMFS) is embrittlement after low temperature (≤380 degrees C) irradiation. The ductile-brittle transition temperature (DBTT) can increase as much as 250 to 300 degrees C and the upper-shelf energy (USE), at the same time, reduce more than 50%. This makes the application temperature range of CMFS is likely between 300 degrees C to 500 degrees C. For the present target design concept, the temperature at the container will be likely controlled in a temperature range between 180 degrees C to 330 degrees C. Hence, CMFS seem to be difficult to apply. However, solution annealed austenitic stainless steels are also difficult to apply as the maximum stress level at the container will be higher than the design stress. The solution to the problem is very likely to use advanced low-activation martensitic/ferritic steels (LAMS) developed by the fusion materials community though the present database on the materials is still very limited

Mercury Thermal Hydraulic Loop (MTHL) Summary Report

Energy Technology Data Exchange (ETDEWEB)

Felde, David K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Crye, Jason Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wendel, Mark W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yoder, Jr, Graydon L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Farquharson, George [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jallouk, Philip A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McFee, Marshall T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pointer, William David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ruggles, Art E. [Univ. of Tennessee, Knoxville, TN (United States); Carbajo, Juan J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-03-01

The Spallation Neutron Source (SNS) is a high-power linear accelerator built at Oak Ridge National Laboratory (ORNL) which incorporates the use of a flowing liquid mercury target. The Mercury Thermal Hydraulic Loop (MTHL) was constructed to investigate and verify the heat transfer characteristics of liquid mercury in a rectangular channel. This report provides a compilation of previously reported results from the water-cooled and electrically heated straight and curved test sections that simulate the geometry of the window cooling channel in the target nose region.

The adsorption of Tl(I), Au(III), Cu(II) and the separation of 199Tl from alpha bombardment of gold target with PDB-18C6

International Nuclear Information System (INIS)

Zhou Dehai; Zhou Jimeng

1989-01-01

The adsorptive behavior of polymer of methyl aldehyde of dibenzo-18-crown-6 (PDB-18C6) in hydrochloric acid medium is studied and it is shown that the adsorption of T1(I), Au(III), and Cu(II) depends on the particle size of the crown ether resins, hydrochloric acid concentration and amount of the crown ether resins used. The difference in the adsorption behavior of different particle sizes of crown ether resins may be used for separating Tl(I), Au(III), and Cu(II) ions. The best eluant of Tl(I) and Au(III) is 0.4 mol/l perchloric acid and 2-ethoxy-ethanol. The recovery for Tl(I) is 82-98.8%. The gold target is bombarded in a 1.2 m cyclotron with 25-27 MeV α-particle with a cumulative beam intensities of 27μA·h, and 199 Tl is separated from the gold target with PDB-18C6. γ-spectrometry has shown that the Tl obtained is 199 Tl of high purity containing only about 0.50% 200 Tl

Trace-level mercury removal from surface water

International Nuclear Information System (INIS)

Klasson, K.T.; Bostick, D.T.

1998-01-01

Many sorbents have been developed for the removal of mercury and heavy metals from waters; however, most of the data published thus far do not address the removal of mercury to the target levels represented in this project. The application to which these sorbents are targeted for use is the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Sorbents with thiouronium, thiol, amine, sulfur, and proprietary functional groups were selected for these studies. Mercury was successfully removed from surface water via adsorption onto Ionac SR-4 and Mersorb resins to levels below the target goal of 12 ng/L in batch studies. A thiol-based resin performed the best, indicating that over 200,000 volumes of water could be treated with one volume of resin. The cost of the resin is approximately $0.24 per 1,000 gal of water

49 CFR 199.245 - Contractor employees.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Contractor employees. 199.245 Section 199.245... Prevention Program § 199.245 Contractor employees. (a) With respect to those covered employees who are contractors or employed by a contractor, an operator may provide by contract that the alcohol testing...

49 CFR 199.115 - Contractor employees.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Contractor employees. 199.115 Section 199.115... § 199.115 Contractor employees. With respect to those employees who are contractors or employed by a contractor, an operator may provide by contract that the drug testing, education, and training required by...

Innovative Waste Management in the Mercury Loop of the EURISOL Multi-MW Converter Target

CERN Document Server

PSI: Jörg Neuhausen, Dorothea Schumann, Rugard Dressler, Susanne Horn, Sabrina Lüthi, Stephan Heinitz, Suresh ChirikiCERN: Thierry Stora, Martin Eller

The choice of mercury as target material imposes various questions concerning the safe operation of such a system that are related to the physical and chemical properties of the target material itself and the nuclear reaction products produced within the target during its life time of several decades. Therefore, a subtask was created within the EURISOL-DS project that is concerned with studying an innovative waste management for the generated radioactivity by chemical means. Such a study strongly depends on the radioactive inventory and its distribution throughout the target and loop system. Radioactive inventory calculations were performed within task 5 [6]. The distribution of nuclear reaction products and their chemical state that can be expected within the target and loop system is one of the topics covered in this report. Based on the results obtained by theoretical studies as well as laboratory scale experiments, the feasibility of waste reduction using chemical methods, both conventional (e.g. leaching...

Cisplatin-induced downregulation of miR-199a-5p increases drug resistance by activating autophagy in HCC cell

International Nuclear Information System (INIS)

Xu, Ning; Zhang, Jianjun; Shen, Conghuan; Luo, Yi; Xia, Lei; Xue, Feng; Xia, Qiang

2012-01-01

Highlights: ► miR-199a-5p levels were significantly decreased after cisplatin treatment. ► Cisplatin treatment induced autophagy activation. ► Cisplatin-induced downregulation of miR-199a-5p increases drug resistance by activating autophagy in HCC cell. -- Abstract: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Systemic chemotherapy plays an important role in the treatment of patients with advanced liver cancer. However, chemoresistance to cisplatin is a major limitation of cisplatin-based chemotherapy in the clinic, and the underlying mechanism of such resistance is not fully understood. In the study, we found that miR-199a-5p levels were significantly reduced in HCC patients treated with cisplatin-based chemotherapy. Cisplatin treatment also resulted in decreased miR-199a-5p levels in human HCC cell lines. Forced expression of miR-199a-5p promoted cisplatin-induced inhibition of cell proliferation. Cisplatin treatment activated autophagy in Huh7 and HepG2 cells, which increased cell proliferation. We further demonstrated that downregulated miR-199a-5p enhanced autophagy activation by targeting autophagy-associated gene 7 (ATG7). More important, autophagy inhibition abrogated miR-199a-5p downregulation-induced cell proliferation. These data demonstrated that miR-199a-5p/autophagy signaling represents a novel pathway regulating chemoresistance, thus offering a new target for chemotherapy of HCC.

Cisplatin-induced downregulation of miR-199a-5p increases drug resistance by activating autophagy in HCC cell

Energy Technology Data Exchange (ETDEWEB)

Xu, Ning; Zhang, Jianjun; Shen, Conghuan; Luo, Yi; Xia, Lei; Xue, Feng [Department of Transplantation and Hepatic Surgery, Renji Hospital, Shanghai Jiaotong University School of Medicine, 1630 Dongfang Road, Shanghai 200127, People' s Republic of China (China); Xia, Qiang, E-mail: xiaqiang1@yahoo.com.cn [Department of Transplantation and Hepatic Surgery, Renji Hospital, Shanghai Jiaotong University School of Medicine, 1630 Dongfang Road, Shanghai 200127, People' s Republic of China (China)

2012-07-13

Highlights: Black-Right-Pointing-Pointer miR-199a-5p levels were significantly decreased after cisplatin treatment. Black-Right-Pointing-Pointer Cisplatin treatment induced autophagy activation. Black-Right-Pointing-Pointer Cisplatin-induced downregulation of miR-199a-5p increases drug resistance by activating autophagy in HCC cell. -- Abstract: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Systemic chemotherapy plays an important role in the treatment of patients with advanced liver cancer. However, chemoresistance to cisplatin is a major limitation of cisplatin-based chemotherapy in the clinic, and the underlying mechanism of such resistance is not fully understood. In the study, we found that miR-199a-5p levels were significantly reduced in HCC patients treated with cisplatin-based chemotherapy. Cisplatin treatment also resulted in decreased miR-199a-5p levels in human HCC cell lines. Forced expression of miR-199a-5p promoted cisplatin-induced inhibition of cell proliferation. Cisplatin treatment activated autophagy in Huh7 and HepG2 cells, which increased cell proliferation. We further demonstrated that downregulated miR-199a-5p enhanced autophagy activation by targeting autophagy-associated gene 7 (ATG7). More important, autophagy inhibition abrogated miR-199a-5p downregulation-induced cell proliferation. These data demonstrated that miR-199a-5p/autophagy signaling represents a novel pathway regulating chemoresistance, thus offering a new target for chemotherapy of HCC.

46 CFR 199.262 - Rescue boats.

Science.gov (United States)

2010-10-01

... SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Cargo Vessels § 199.262 Rescue boats. (a) Each cargo vessel must carry at least one rescue boat. Each rescue boat must be approved under approval... 46 Shipping 7 2010-10-01 2010-10-01 false Rescue boats. 199.262 Section 199.262 Shipping COAST...

46 CFR 199.261 - Survival craft.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft. 199.261 Section 199.261 Shipping COAST... SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Cargo Vessels § 199.261 Survival craft. (a) Each survival craft must be approved and equipped as follows: (1) Each lifeboat must be a totally...

miR-199a Links MeCP2 with mTOR Signaling and Its Dysregulation Leads to Rett Syndrome Phenotypes

Directory of Open Access Journals (Sweden)

Keita Tsujimura

2015-09-01

Full Text Available Rett syndrome (RTT is a neurodevelopmental disorder caused by MECP2 mutations. Although emerging evidence suggests that MeCP2 deficiency is associated with dysregulation of mechanistic target of rapamycin (mTOR, which functions as a hub for various signaling pathways, the mechanism underlying this association and the molecular pathophysiology of RTT remain elusive. We show here that MeCP2 promotes the posttranscriptional processing of particular microRNAs (miRNAs as a component of the microprocessor Drosha complex. Among the MeCP2-regulated miRNAs, we found that miR-199a positively controls mTOR signaling by targeting inhibitors for mTOR signaling. miR-199a and its targets have opposite effects on mTOR activity, ameliorating and inducing RTT neuronal phenotypes, respectively. Furthermore, genetic deletion of miR-199a-2 led to a reduction of mTOR activity in the brain and recapitulated numerous RTT phenotypes in mice. Together, these findings establish miR-199a as a critical downstream target of MeCP2 in RTT pathogenesis by linking MeCP2 with mTOR signaling.

A 3'-untranslated region (3'UTR) induces organ adhesion by regulating miR-199a* functions.

Science.gov (United States)

Lee, Daniel Y; Shatseva, Tatiana; Jeyapalan, Zina; Du, William W; Deng, Zhaoqun; Yang, Burton B

2009-01-01

Mature microRNAs (miRNAs) are single-stranded RNAs of 18-24 nucleotides that repress post-transcriptional gene expression. However, it is unknown whether the functions of mature miRNAs can be regulated. Here we report that expression of versican 3'UTR induces organ adhesion in transgenic mice by modulating miR-199a* activities. The study was initiated by the hypothesis that the non-coding 3'UTR plays a role in the regulation of miRNA function. Transgenic mice expressing a construct harboring the 3'UTR of versican exhibits the adhesion of organs. Computational analysis indicated that a large number of microRNAs could bind to this fragment potentially including miR-199a*. Expression of versican and fibronectin, two targets of miR-199a*, are up-regulated in transgenic mice, suggesting that the 3'UTR binds and modulates miR-199a* activities, freeing mRNAs of versican and fibronectin from being repressed by miR-199a*. Confirmation of the binding was performed by PCR using mature miR-199a* as a primer and the targeting was performed by luciferase assays. Enhanced adhesion by expression of the 3'UTR was confirmed by in vitro assays. Our results demonstrated that upon arrival in cytoplasm, miRNA activities can be modulated locally by the 3'UTR. Our assay may be developed as sophisticated approaches for studying the mutual regulation of miRNAs and mRNAs in vitro and in vivo. We anticipate that expression of the 3'UTR may be an approach in the development of gene therapy.

MicroRNA-199 suppresses cell proliferation, migration and invasion by downregulating RGS17 in hepatocellular carcinoma.

Science.gov (United States)

Zhang, Wei; Qian, Sheng; Yang, Guowei; Zhu, Liang; Zhou, Bo; Wang, Jianhua; Liu, Rong; Yan, Zhiping; Qu, Xudong

2018-06-15

Hepatocellular carcinoma (HCC), the most common primary tumor of the liver, has a poor prognosis and shows rapid progression. MicroRNAs (miRNAs) play important roles in carcinogenesis and tumor progression. Regulators of G-protein signaling (RGS) are critical for defining G-protein-dependent signal fidelity. RGS17 plays an important role in the regulation of cancer cell proliferation, migration and invasion. Here, we showed that miR-199 was downregulated in a hepatocarcinoma cell line. Overexpression of miR-199 significantly suppressed HCC cell proliferation, migration, and invasion in vitro. RGS17 overexpression promoted HCC cell proliferation, migration, and invasion, and reversed the miR-199 mediated inhibition of proliferation, migration, and invasion. Dual-fluorescence reporter experiments confirmed that miR-199 downregulated RGS17 by direct interaction with the 3'-UTR of RGS17 mRNA. In vivo studies showed that miR-199 overexpression significantly inhibited the growth of tumors. Taken together, the results suggested that miR-199 inhibited tumor growth and metastasis by targeting RGS17. Published by Elsevier B.V.

Vaporization of mercury from molten lead droplets doped with mercury: Pb/Hg source term experiment for the APT/SILC target

International Nuclear Information System (INIS)

Tutu, N.K.; Greene, G.A.

1994-09-01

Experiments were performed to measure the fraction of mercury inventory released when droplets of molten lead, doped with a known concentration of mercury, fall through a controlled environment. The temperature of molten droplets ranged from 335 C to 346 C, and the concentration of mercury in the droplets ranged from 0.2 mass % to 1.0 mass %. The environment consisted of an air stream, at a temperature nominally equal to the melt temperature, and moving vertically upwards at a velocity of 10 cm/s. Direct observations and chemical analysis showed that no mercury was released from the molten droplets. Based upon the experimental results, it is concluded that no mercury vapor is likely to be released from the potentially molten source rod material in the APT-SILC Neutron Source Array to the confinement atmosphere during a postulated Large Break Loss Of Coolant Accident scenario leading to the melting of a fraction of the source rods

A 3'-untranslated region (3'UTR induces organ adhesion by regulating miR-199a* functions.

Directory of Open Access Journals (Sweden)

Daniel Y Lee

Full Text Available Mature microRNAs (miRNAs are single-stranded RNAs of 18-24 nucleotides that repress post-transcriptional gene expression. However, it is unknown whether the functions of mature miRNAs can be regulated. Here we report that expression of versican 3'UTR induces organ adhesion in transgenic mice by modulating miR-199a* activities. The study was initiated by the hypothesis that the non-coding 3'UTR plays a role in the regulation of miRNA function. Transgenic mice expressing a construct harboring the 3'UTR of versican exhibits the adhesion of organs. Computational analysis indicated that a large number of microRNAs could bind to this fragment potentially including miR-199a*. Expression of versican and fibronectin, two targets of miR-199a*, are up-regulated in transgenic mice, suggesting that the 3'UTR binds and modulates miR-199a* activities, freeing mRNAs of versican and fibronectin from being repressed by miR-199a*. Confirmation of the binding was performed by PCR using mature miR-199a* as a primer and the targeting was performed by luciferase assays. Enhanced adhesion by expression of the 3'UTR was confirmed by in vitro assays. Our results demonstrated that upon arrival in cytoplasm, miRNA activities can be modulated locally by the 3'UTR. Our assay may be developed as sophisticated approaches for studying the mutual regulation of miRNAs and mRNAs in vitro and in vivo. We anticipate that expression of the 3'UTR may be an approach in the development of gene therapy.

46 CFR 199.180 - Training and drills.

Science.gov (United States)

2010-10-01

... problems of hypothermia, first aid treatment for hypothermia, and other appropriate first aid procedures... 46 Shipping 7 2010-10-01 2010-10-01 false Training and drills. 199.180 Section 199.180 Shipping... LIFESAVING SYSTEMS FOR CERTAIN INSPECTED VESSELS Requirements for All Vessels § 199.180 Training and drills...

49 CFR 199.113 - Employee assistance program.

Science.gov (United States)

2010-10-01

... TESTING Drug Testing § 199.113 Employee assistance program. (a) Each operator shall provide an employee assistance program (EAP) for its employees and supervisory personnel who will determine whether an employee... 49 Transportation 3 2010-10-01 2010-10-01 false Employee assistance program. 199.113 Section 199...

Pressure and stress waves in a spallation neutron source mercury target generated by high-power proton pulses

CERN Document Server

Futakawa, M; Conrad, H; Stechemesser, H

2000-01-01

The international ASTE collaboration has performed a first series of measurements on a spallation neutron source target at the Alternating Gradient Synchrotron (AGS) in Brookhaven. The dynamic response of a liquid mercury target hit by high-power proton pulses of about 40 ns duration has been measured by a laser Doppler technique and compared with finite elements calculations using the ABAQUS code. It is shown that the calculation can describe the experimental results for at least the time interval up to 100 mu s after the pulse injection. Furthermore, it has been observed that piezoelectric pressure transducers cannot be applied in the high gamma-radiation field of a spallation target.

Performance Characteristics of CA 19-9 Radioimmunoassay and Clinical Significance of Serum CA 19-9 Assay in Patients with Malignancy

International Nuclear Information System (INIS)

Kim, Sang Eun; Shong, Young Kee; Cho, Bo Youn; Kim, Noe Kyeong; Koh, Chang Soon; Lee, Mun Ho; Hong, Seong Woon; Hong, Kee Suk

1985-01-01

To evaluate the performance characteristics of CA 19-9 radioimmunoassay and the clinical significance of serum CA 19-9 assay in patients with malignancy, serum. CA 19-9 levels were measured by radioimmunoassay using monoclonal antibody in 135 normal controls, 81 patients with various untreated malignancy, 9 patients of postoperative colon cancer without recurrence and 20 patients with benign gastrointestinal diseases, who visited Seoul National University Hospital from June, 1984 to March, 1985. The results were as follows; 1) The CA 19-9 radioimmunoassay was simple to perform and can be completed in one work day. And the between-assay reproducibility and the assay recovery were both excellent. 2) The mean serum CA 19-9 level in 135 normal controls was 8.4±4.2 U/mL. Normal upper limit of serum CA 19-9 was defined as 21.0 U/mL. 4 out of 135 (3.0%) normal controls showed elevated CA 19-9 levels above the normal upper limit. 3) One out of 20 (5.0%) patients with benign gastrointestinal diseases showed elevated serum CA 19-9 level above the normal upper limit. 4) In 81 patients with various untreated malignancy, 41 patients (50.6%) showed elevated serum CA 19-9 levels. 66.7% of 18 patients with colorectal cancer, 100% of 2 patients with pancreatic cancer, 100% of 3 patients with common bile duct cancer, 47.1% of 17 patients with stomach cancer, 28.6% of 28 patients with hepatoma and 60.0% of 5 gastrointestinal tract cancers showed elevated serum CA 19-9 levels. 5) The sensitivities of serum CA 19-9 related to respectability in colorectal and stomach cancer were 33.3% in resectable colorectal cancer, 83.3% in unresectable colorectal cancer, 41.7% in resectable stomach cancer, 60.0% in unresectable stomach cancer respectively. 6) The sensitivity of serum CA 19-9 in 9 patients of postoperative colorectal cancer without recurrence were 33.3% and significantly decreased compared with that of untreated colorectal cancer, 66.7% (p<0.05). 7) In Patients with colorectal cancer

Toenail mercury and dyslipidemia: Interaction with selenium.

Science.gov (United States)

Park, Kyong; Seo, Eunmin

2017-01-01

Although compelling evidences from in vivo and in vitro studies exist, limited studies have examined the association between chronic mercury exposure and dyslipidemia. Particularly, data are sparse regarding the influence of selenium on this association of mercury with dyslipidemia in humans. The purpose of the current study was to examine the associations of toenail mercury with dyslipidemia and its components, and to examine whether selenium in toenails modifies these associations. We performed cross-sectional analyses using baseline data from a cohort in the Yeungnam area in South Korea, including 232 men and 269 women. Toenail mercury and selenium concentrations were quantified using neutron activation analysis, and fasting serum lipid measurements were obtained through the medical examination. Odds ratios of the prevalent hypercholesterolemia, hyper-LDL-cholesterolemia, hypo-HDL-cholesterolemia, hypertriglyceridemia, and dyslipidemia in correlation with mercury levels were calculated using multivariable logistic regression. The mean levels of toenail mercury were 0.47μg/g for men and 0.34μg/g for women. After adjustment for multiple confounding variables, participants in the highest tertile of toenail mercury levels had 4.08 (95% CI 1.09-15.32, p for trend=0.02) times higher risk of hyper-LDL-cholesterolemia, and 2.24 (95% CI 1.15-4.37, p for trend=0.004) times higher risk of dyslipidemia than those in the lowest tertile. Selenium is a significant effect-modifier for these associations; the highest tertile of toenail mercury were significantly associated with a higher risk of hypercholesterolemia (OR 5.25, 95% CI 1.04-26.38) and dyslipidemia (OR 2.98, 95% CI 1.16-7.66) compared to the lowest tertile at toenail selenium levels ≤0.685μg/g, while these associations became weak and non-significant, showing OR 0.98 and 95% CI 0.25-3.80 for hypercholesterolemia and OR 1.99 and 95% CI 0.73-5.45 for dyslipidemia at toenail selenium levels >0.685μg/g. We

Isotopic study of mercury sources and transfer between a freshwater lake and adjacent forest food web

International Nuclear Information System (INIS)

Kwon, Sae Yun; Blum, Joel D.; Nadelhoffer, Knute J.; Timothy Dvonch, J.; Tsui, Martin Tsz-Ki

2015-01-01

Studies of monomethylmercury (MMHg) sources and biogeochemical pathways have been extensive in aquatic ecosystems, but limited in forest ecosystems. Increasing evidence suggests that there is significant mercury (Hg) exchange between aquatic and forest ecosystems. We use Hg stable isotope ratios (δ 202 Hg and Δ 199 Hg) to investigate the relative importance of MMHg sources and assess Hg transfer pathways between Douglas Lake and adjacent forests located at the University of Michigan Biological Station, USA. We characterize Hg isotopic compositions of basal resources and use linear regression of % MMHg versus δ 202 Hg and Δ 199 Hg to estimate Hg isotope values for inorganic mercury (IHg) and MMHg in the aquatic and adjacent forest food webs. In the aquatic ecosystem, we found that lake sediment represents a mixture of IHg pools deposited via watershed runoff and precipitation. The δ 202 Hg and Δ 199 Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ 199 Hg value estimated for MMHg in the aquatic food web indicates that MMHg is subjected to ~ 20% photochemical degradation prior to bioaccumulation. In the forest ecosystem, we found a significant negative relationship between total Hg and δ 202 Hg and Δ 199 Hg of soil collected at multiple distances from the lakeshore and lake sediment. This suggests that IHg input from watershed runoff provides an important Hg transfer pathway between the forest and aquatic ecosystems. We measured Δ 199 Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ 199 Hg values correspond to the % canopy cover suggesting that forest MMHg is subjected to varying extents of photochemical degradation and the extent may be controlled by sunlight. Our study demonstrates that the use of Hg isotopes adds important new insight into the relative importance of MMHg sources and complex Hg transfer

Isotopic study of mercury sources and transfer between a freshwater lake and adjacent forest food web

Energy Technology Data Exchange (ETDEWEB)

Kwon, Sae Yun, E-mail: saeyunk@umich.edu [Department of Earth and Environmental Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI 48109 (United States); Blum, Joel D. [Department of Earth and Environmental Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI 48109 (United States); Department of Ecology and Evolutionary Biology, University of Michigan, 830 N. University Ave, Ann Arbor, MI 48109 (United States); Nadelhoffer, Knute J. [Department of Ecology and Evolutionary Biology, University of Michigan, 830 N. University Ave, Ann Arbor, MI 48109 (United States); Timothy Dvonch, J. [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Tsui, Martin Tsz-Ki [Department of Biology, University of North Carolina at Greensboro, 321 McIver Street, Greensboro, NC 27402 (United States)

2015-11-01

Studies of monomethylmercury (MMHg) sources and biogeochemical pathways have been extensive in aquatic ecosystems, but limited in forest ecosystems. Increasing evidence suggests that there is significant mercury (Hg) exchange between aquatic and forest ecosystems. We use Hg stable isotope ratios (δ{sup 202}Hg and Δ{sup 199}Hg) to investigate the relative importance of MMHg sources and assess Hg transfer pathways between Douglas Lake and adjacent forests located at the University of Michigan Biological Station, USA. We characterize Hg isotopic compositions of basal resources and use linear regression of % MMHg versus δ{sup 202}Hg and Δ{sup 199}Hg to estimate Hg isotope values for inorganic mercury (IHg) and MMHg in the aquatic and adjacent forest food webs. In the aquatic ecosystem, we found that lake sediment represents a mixture of IHg pools deposited via watershed runoff and precipitation. The δ{sup 202}Hg and Δ{sup 199}Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ{sup 199}Hg value estimated for MMHg in the aquatic food web indicates that MMHg is subjected to ~ 20% photochemical degradation prior to bioaccumulation. In the forest ecosystem, we found a significant negative relationship between total Hg and δ{sup 202}Hg and Δ{sup 199}Hg of soil collected at multiple distances from the lakeshore and lake sediment. This suggests that IHg input from watershed runoff provides an important Hg transfer pathway between the forest and aquatic ecosystems. We measured Δ{sup 199}Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ{sup 199}Hg values correspond to the % canopy cover suggesting that forest MMHg is subjected to varying extents of photochemical degradation and the extent may be controlled by sunlight. Our study demonstrates that the use of Hg isotopes adds important new insight into the relative

46 CFR 199.290 - Stowage of survival craft.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 199.290 Section 199.290... of survival craft. (a) To meet the requirements of § 199.130(b)(1), each lifeboat— (1) On a cargo... required under § 199.261(e), no stowage position or muster and embarkation station for a survival craft on...

Measurement of activation reaction rate distribution on a mercury target with a lead-reflector and light-water-moderator for high energy proton bombardment using AGS accelerator

International Nuclear Information System (INIS)

Kasugai, Yoshimi; Takada, Hiroshi; Meigo, Shin-ichiro

2001-02-01

Characteristic of spallation neutrons driven by GeV protons from a mercury target with a lead-reflector and light-water-moderator was studied experimentally using the Alternating Gradient Synchrotron (AGS) facility of Brookhaven National Laboratory in a framework of the ASTE (AGS Spallation Target Experiment) collaboration. Several reaction rates along with the mercury target were measured with the activation method at incident proton energies of 1.94, 12 and 24 GeV. Indium, niobium, aluminum, cobalt, nickel and bismuth were used as activation detectors to cover the threshold energy of between 0.33 and 40.9 MeV. This report summarizes the experimental procedure with all the measured data. (author)

Atmospheric mercury inputs in montane soils increase with elevation: evidence from mercury isotope signatures.

Science.gov (United States)

Zhang, Hua; Yin, Run-sheng; Feng, Xin-bin; Sommar, Jonas; Anderson, Christopher W N; Sapkota, Atindra; Fu, Xue-wu; Larssen, Thorjørn

2013-11-25

The influence of topography on the biogeochemical cycle of mercury (Hg) has received relatively little attention. Here, we report the measurement of Hg species and their corresponding isotope composition in soil sampled along an elevational gradient transect on Mt. Leigong in subtropical southwestern China. The data are used to explain orography-related effects on the fate and behaviour of Hg species in montane environments. The total- and methyl-Hg concentrations in topsoil samples show a positive correlation with elevation. However, a negative elevation dependence was observed in the mass-dependent fractionation (MDF) and mass-independent fractionation (MIF) signatures of Hg isotopes. Both a MIF (Δ(199)Hg) binary mixing approach and the traditional inert element method indicate that the content of Hg derived from the atmosphere distinctly increases with altitude.

A Target-Lighted dsDNA-Indicator for High-Performance Monitoring of Mercury Pollution and Its Antagonists Screening.

Science.gov (United States)

Qing, Zhihe; Zhu, Lixuan; Li, Xiaoxuan; Yang, Sheng; Zou, Zhen; Guo, Jingru; Cao, Zhong; Yang, Ronghua

2017-10-17

As well-known, the excessive discharge of heavy-metal mercury not only destroys the ecological environment, bust also leads to severe damage of human health after ingestion via drinking and bioaccumulation of food chains, and mercury ion (Hg 2+ ) is designated as one of most prevalent toxic metal ions in drinking water. Thus, the high-performance monitoring of mercury pollution is necessary. Functional nucleic acids have been widely used as recognition probes in biochemical sensing. In this work, a carbazole derivative, ethyl-4-[3,6-bis(1-methyl-4-vinylpyridium iodine)-9H-carbazol -9-yl)] butanoate (EBCB), has been synthesized and found as a target-lighted DNA fluorescent indicator. As a proof-of-concept, Hg 2+ detection was carried out based on EBCB and Hg 2+ -mediated conformation transformation of a designed DNA probe. By comparison with conventional nucleic acid indicators, EBCB held excellent advantages, such as minimal background interference and maximal sensitivity. Outstanding detection capabilities were displayed, especially including simple operation (add-and-read manner), ultrarapidity (30 s), and low detection limit (0.82 nM). Furthermore, based on these advantages, the potential for high-performance screening of mercury antagonists was also demonstrated by the fluorescence change of EBCB. Therefore, we believe that this work is meaningful in pollution monitoring, environment restoration and emergency treatment, and may pave a way to apply EBCB as an ideal signal transducer for development of high-performance sensing strategies.

Mercury

International Nuclear Information System (INIS)

Vilas, F.; Chapman, C.R.; Matthews, M.S.

1988-01-01

Papers are presented on future observations of and missions to Mercury, the photometry and polarimetry of Mercury, the surface composition of Mercury from reflectance spectrophotometry, the Goldstone radar observations of Mercury, the radar observations of Mercury, the stratigraphy and geologic history of Mercury, the geomorphology of impact craters on Mercury, and the cratering record on Mercury and the origin of impacting objects. Consideration is also given to the tectonics of Mercury, the tectonic history of Mercury, Mercury's thermal history and the generation of its magnetic field, the rotational dynamics of Mercury and the state of its core, Mercury's magnetic field and interior, the magnetosphere of Mercury, and the Mercury atmosphere. Other papers are on the present bounds on the bulk composition of Mercury and the implications for planetary formation processes, the building stones of the planets, the origin and composition of Mercury, the formation of Mercury from planetesimals, and theoretical considerations on the strange density of Mercury

Mercury heavy-metal-induced physiochemical changes and genotoxic alterations in water hyacinths [Eichhornia crassipes (Mart.)].

Science.gov (United States)

Malar, Srinivasan; Sahi, Shivendra Vikram; Favas, Paulo J C; Venkatachalam, Perumal

2015-03-01

Mercury heavy metal pollution has become an important environmental problem worldwide. Accumulation of mercury ions by plants may disrupt many cellular functions and block normal growth and development. To assess mercury heavy metal toxicity, we performed an experiment focusing on the responses of Eichhornia crassipes to mercury-induced oxidative stress. E. crassipes seedlings were exposed to varying concentrations of mercury to investigate the level of mercury ions accumulation, changes in growth patterns, antioxidant defense mechanisms, and DNA damage under hydroponics system. Results showed that plant growth rate was significantly inhibited (52 %) at 50 mg/L treatment. Accumulation of mercury ion level were 1.99 mg/g dry weight, 1.74 mg/g dry weight, and 1.39 mg/g dry weight in root, leaf, and petiole tissues, respectively. There was a decreasing trend for chlorophyll a, b, and carotenoids with increasing the concentration of mercury ions. Both the ascorbate peroxidase and malondialdehyde contents showed increased trend in leaves and roots up to 30 mg/L mercury treatment and slightly decreased at the higher concentrations. There was a positive correlation between heavy metal dose and superoxide dismutase, catalase, and peroxidase antioxidative enzyme activities which could be used as biomarkers to monitor pollution in E. crassipes. Due to heavy metal stress, some of the normal DNA bands were disappeared and additional bands were amplified compared to the control in the random amplified polymorphic DNA (RAPD) profile. Random amplified polymorphic DNA results indicated that genomic template stability was significantly affected by mercury heavy metal treatment. We concluded that DNA changes determined by random amplified polymorphic DNA assay evolved a useful molecular marker for detection of genotoxic effects of mercury heavy metal contamination in plant species.

46 CFR 199.03 - Relationship to international standards.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Relationship to international standards. 199.03 Section 199.03 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LIFESAVING APPLIANCES AND ARRANGEMENTS LIFESAVING SYSTEMS FOR CERTAIN INSPECTED VESSELS General § 199.03 Relationship to international...

Mercury emission from crematories in Japan

Directory of Open Access Journals (Sweden)

M. Takaoka

2010-04-01

Full Text Available Anthropogenic sources of mercury emissions have a significant impact on global pollution. Therefore, finding uncharacterised sources and assessing the emissions from these sources are important. However, limited data are available worldwide on mercury emissions from crematories. In Japan, 99.9% of dead bodies are cremated, which is the highest percentage in the world, and more than 1600 crematories are in operation. We thus focused on emissions from crematories in Japan. The number of targeted facilities was seven, and we used continuous emission monitoring to measure the mercury concentrations and investigate mercury behaviour. The total mercury concentrations in stack gases were a few μg/Nm³ (normal cubic meters. Considering the time profile of mercury and its species in cremations, the findings confirmed that the mercury in stack gas originated from dental amalgam. The amount of mercury emissions was calculated using the total concentration and gas flow rate. Furthermore, the annual amount of mercury emission from crematories in Japan was estimated by using the total number of corpses. The emission amount was considerably lower than that estimated in the United Kingdom. From statistical analyses on population demographics and measurements, future total emissions from crematories were also predicted. As a result, the amount of mercury emitted by crematories will likely increase by 2.6-fold from 2007 to 2037.

A 3′-Untranslated Region (3′UTR) Induces Organ Adhesion by Regulating miR-199a* Functions

Science.gov (United States)

Lee, Daniel Y.; Shatseva, Tatiana; Jeyapalan, Zina; Du, William W.; Deng, Zhaoqun; Yang, Burton B.

2009-01-01

Mature microRNAs (miRNAs) are single-stranded RNAs of 18–24 nucleotides that repress post-transcriptional gene expression. However, it is unknown whether the functions of mature miRNAs can be regulated. Here we report that expression of versican 3′UTR induces organ adhesion in transgenic mice by modulating miR-199a* activities. The study was initiated by the hypothesis that the non-coding 3′UTR plays a role in the regulation of miRNA function. Transgenic mice expressing a construct harboring the 3′UTR of versican exhibits the adhesion of organs. Computational analysis indicated that a large number of microRNAs could bind to this fragment potentially including miR-199a*. Expression of versican and fibronectin, two targets of miR-199a*, are up-regulated in transgenic mice, suggesting that the 3′UTR binds and modulates miR-199a* activities, freeing mRNAs of versican and fibronectin from being repressed by miR-199a*. Confirmation of the binding was performed by PCR using mature miR-199a* as a primer and the targeting was performed by luciferase assays. Enhanced adhesion by expression of the 3′UTR was confirmed by in vitro assays. Our results demonstrated that upon arrival in cytoplasm, miRNA activities can be modulated locally by the 3′UTR. Our assay may be developed as sophisticated approaches for studying the mutual regulation of miRNAs and mRNAs in vitro and in vivo. We anticipate that expression of the 3′UTR may be an approach in the development of gene therapy. PMID:19223980

26 CFR 1.199-0 - Table of contents.

Science.gov (United States)

2010-04-01

.... This section lists the section headings that appear in §§ 1.199-1 through 1.199-9. § 1.199-1Income... property. (2) Examples. (3) Hedging transactions. (i) In general. (ii) Currency fluctuations. (iii) Effect... general. (2) Example. (3) Net operating loss carrybacks and carryovers. (4) Losses used to reduce taxable...

46 CFR 199.201 - Survival craft.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft. 199.201 Section 199.201 Shipping COAST... craft. (a) Each survival craft must be approved and equipped as follows: (1) Each lifeboat must be... addition to the survival craft required in paragraph (b)(1) of this section, additional liferafts must be...

MESSENGER at Mercury: Early Orbital Operations

Science.gov (United States)

McNutt, Ralph L., Jr; Solomon, Sean C.; Bedini, Peter D.; Anderson, Brian J.; Blewett, David T.; Evans, Larry G.; Gold, Robert E.; Krimigis, Stamatios M.; Murchie, Scott L.; Nittler, Larry R.;

46 CFR 199.230 - Stowage of survival craft.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 199.230 Section 199.230... Stowage of survival craft. (a) To meet the requirements of § 199.130(b)(1), each lifeboat on a passenger... height of a survival craft must take into account the vessel's escape provisions, the vessel's size, and...

Mercury speciation analysis in marine samples by HPLC-ICPMS

DEFF Research Database (Denmark)

Rasmussen, Rie Romme; Svendsen, Maja Erecius; Herbst, M. Birgitte Koch

Mercury (Hg) is a naturally occurring element, which is found in the earth’s crust and can be released into the environment through both natural and anthropogenic processes. Mercury exists as elemental mercury (metallic), inorganic mercury and organic mercury (primarily methylmercury......). Methylmercury is highly toxic, particularly to the nervous system, and the developing brain is thought to be the most sensitive target organ for methylmercury toxicity. Methylmercury bioaccumulates and biomagnifies along the food chain and it is the most common mercury species in fish and seafood. Human...... hydrochloric acid by sonication. Hereby the protein-bound mercury species are released. The extracts were then centrifuged (10 min at 3170 x g) and the supernatant decanted (extraction step was repeated twice). The combined extracts were added 10 M sodium hydroxide to increase pH, following further dilution...

Mercury's Messenger

Science.gov (United States)

Chapman, Clark R.

2004-01-01

Forty years after Mariner 2, planetary exploration has still only just begun, and many more missions are on drawing boards, nearing the launch pad, or even en route across interplanetary space to their targets. One of the most challenging missions that will be conducted this decade is sending the MESSENGER spacecraft to orbit the planet Mercury.…

Gravity, Topography, and Magnetic Field of Mercury from Messenger

Science.gov (United States)

Neumann, Gregory A.; Solomon, Sean C.; Zuber, Maria T.; Phillips, Roger J.; Barnouin, Olivier; Ernst, Carolyn; Goosens, Sander; Hauck, Steven A., II; Head, James W., III; Johnson, Catherine L.;

Biological rational for sequential targeting of Bruton tyrosine kinase and Bcl-2 to overcome CD40-induced ABT-199 resistance in mantle cell lymphoma.

Science.gov (United States)

Chiron, David; Dousset, Christelle; Brosseau, Carole; Touzeau, Cyrille; Maïga, Sophie; Moreau, Philippe; Pellat-Deceunynck, Catherine; Le Gouill, Steven; Amiot, Martine

2015-04-20

The aggressive biological behavior of mantle cell lymphoma (MCL) and its short response to current treatment highlight a great need for better rational therapy. Herein, we investigate the ability of ABT-199, the Bcl-2-selective BH3 mimetic, to kill MCL cells. Among MCL cell lines tested (n = 8), only three were sensitive (LD50 < 200 nM). In contrast, all primary MCL samples tested (n = 11) were highly sensitive to ABT-199 (LD50 < 10 nM). Mcl-1 and Bcl-xL both confer resistance to ABT-199-specific killing and BCL2/(BCLXL+MCL1) mRNA ratio is a strong predictor of sensitivity. By mimicking the microenvironment through CD40 stimulation, we show that ABT-199 sensitivity is impaired through activation of NF-kB pathway and Bcl-x(L) up-regulation. We further demonstrate that resistance is rapidly lost when MCL cells detach from CD40L-expressing fibroblasts. It has been reported that ibrutinib induces lymphocytosis in vivo holding off malignant cells from their protective microenvironment. We show here for two patients undergoing ibrutinib therapy that mobilized MCL cells are highly sensitive to ABT-199. These results provide evidence that in situ ABT-199 resistance can be overcome when MCL cells escape from the lymph nodes. Altogether, our data support the clinical application of ABT-199 therapy both as a single agent and in sequential combination with BTK inhibitors.

Transient analysis of mercury experimental loop using the RELAP5 code. 3rd report. Transient analysis using mercury properties

International Nuclear Information System (INIS)

Kinoshita, Hidetaka; Kaminaga, Masanori; Hino, Ryutaro

2000-02-01

In order to promote the Neutron Science Project of JAERI, the design of a 5MW-spallation target system is in progress with the purpose of producing a practical neutron application while at the same time adhering to the highest levels of safety. To establish the safety of the target system, it is important to understand the transient behaviors during anticipated operational events of the system, and to design the safety protection systems for the safe termination of the transients. This report presents the analytical results of transient behaviors in the mercury experimental loop using mercury properties. At first, the analytical pressure distributions were compared with experimental data measured with the mercury experimental loop. The modeling data were modified to reproduce the actual pressure distributions of the mercury experimental loop. Then a loss of forced convection and a loss of coolant accident were analyzed. In the case of the pump trip, the transient analysis was conducted using two types of mercury pumps, the mechanical type pump with moment of inertia, and the electrical-magnetic type pump without moment of inertia. The results show there was no clear difference in the two analyses, since the mercury had a large inertia, which was 13.5 times that of the water. Moreover, in the case of a pipe rupture at the pump exit, a moderate pressure decrease was confirmed when a small breakage area existed in which the coolant flowed out gradually. Based on these results, it was appeared that the transient fluctuation of pressure in the mercury loop would not become large and accidents would have to be detected by small fluctuations in pressure. Based on these analyses, we plan to conduct a simulation test to verify the RELAP5 code, and then the analysis of a full-scale mercury system will be performed. (author)

Performance characteristics of CA 19-9 radioimmunoassay and clinical significance of serum CA 19-9 assay in patients with malignancy

International Nuclear Information System (INIS)

Kim, S.E.; Shong, Y.K.; Cho, B.Y.; Kim, N.K.; Koh, C.S.; Lee, M.H.; Hong, K.S.

1985-01-01

To evaluate the performance characteristics of CA 19-9 radioimmunoassay and the clinical significance of serum CA 19-9 assay in patients with malignancy, serum CA 19-9 levels were measured by radioimmunoassay using monoclonal antibody in 135 normal controls, 81 patients with various untreated malignancy, 9 patients of postoperative colon cancer without recurrence and 20 patients with benign gastrointestinal diseases, who visited Seoul National University Hospital from June, 1984 to March, 1985. (Author)

40 CFR 264.199 - Special requirements for incompatible wastes.

Science.gov (United States)

2010-07-01

... DISPOSAL FACILITIES Tank Systems § 264.199 Special requirements for incompatible wastes. (a) Incompatible... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Special requirements for incompatible wastes. 264.199 Section 264.199 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED...

Target molecular weights for red cell band 3 stilbene and mercurial binding sites

International Nuclear Information System (INIS)

Verkman, A.S.; Skorecki, K.L.; Jung, C.Y.; Ausiello, D.A.

1986-01-01

Radiation inactivation was used to measure the target sizes for binding of disulfonic stilbene anion transport inhibitor 4,4'-dibenzamido-2,2'-disulfonic stilbene (DBDS) and mercurial water transport inhibitor p-chloromercuribenzene sulfonate (pCMBS) to human erythrocytes. The measured target size for erythrocyte ghost acetylcholinesterase was 78 +/- 3 kDa. DBDS binding to ghost membranes was measured by a fluorescence enhancement technique. Radiation (0-26 Mrad) had no effect on total membrane protein and DBDS binding affinity, whereas DBDS binding stoichiometry decreased exponentially with radiation dose, giving a target size of 59 +/- 4 kDa. H2-4,4'-diisothiocyano-2,2'-disulfonic stilbene (H2-DIDS, 5 microM) blocked greater than 95% of DBDS binding at all radiation doses. pCMBS binding was measured from the time course of tryptophan fluorescence quenching in ghosts treated with the sulfhydryl reagent N-ethylmaleimide (NEM). Radiation did not affect the kinetics of tryptophan quenching, whereas the total amplitude of the fluorescence signal inactivated with radiation with a target size of 31 +/- 6 kDa. These results support the notion that DBDS and pCMBS bind to the transmembrane domain of erythrocyte band 3 in NEM-treated ghosts and demonstrate that radiation inactivation may probe a target significantly smaller than a covalently linked protein subunit. The small target size for the band 3 stilbene binding site may correspond to the intramembrane domain of the band 3 monomer (52 kDa), which is physically distinct from the cytoplasmic domain (42 kDa)

Source tracing of natural organic matter bound mercury in boreal forest runoff with mercury stable isotopes.

Science.gov (United States)

Jiskra, Martin; Wiederhold, Jan G; Skyllberg, Ulf; Kronberg, Rose-Marie; Kretzschmar, Ruben

2017-10-18

Terrestrial runoff represents a major source of mercury (Hg) to aquatic ecosystems. In boreal forest catchments, such as the one in northern Sweden studied here, mercury bound to natural organic matter (NOM) represents a large fraction of mercury in the runoff. We present a method to measure Hg stable isotope signatures of colloidal Hg, mainly complexed by high molecular weight or colloidal natural organic matter (NOM) in natural waters based on pre-enrichment by ultrafiltration, followed by freeze-drying and combustion. We report that Hg associated with high molecular weight NOM in the boreal forest runoff has very similar Hg isotope signatures as compared to the organic soil horizons of the catchment area. The mass-independent fractionation (MIF) signatures (Δ 199 Hg and Δ 200 Hg) measured in soils and runoff were in agreement with typical values reported for atmospheric gaseous elemental mercury (Hg 0 ) and distinctly different from reported Hg isotope signatures in precipitation. We therefore suggest that most Hg in the boreal terrestrial ecosystem originated from the deposition of Hg 0 through foliar uptake rather than precipitation. Using a mixing model we calculated the contribution of soil horizons to the Hg in the runoff. At moderate to high flow runoff conditions, that prevailed during sampling, the uppermost part of the organic horizon (Oe/He) contributed 50-70% of the Hg in the runoff, while the underlying more humified organic Oa/Ha and the mineral soil horizons displayed a lower mobility of Hg. The good agreement of the Hg isotope results with other source tracing approaches using radiocarbon signatures and Hg : C ratios provides additional support for the strong coupling between Hg and NOM. The exploratory results from this study illustrate the potential of Hg stable isotopes to trace the source of Hg from atmospheric deposition through the terrestrial ecosystem to soil runoff, and provide a basis for more in-depth studies investigating the

40 CFR 265.199 - Special requirements for incompatible wastes.

Science.gov (United States)

2010-07-01

..., STORAGE, AND DISPOSAL FACILITIES Tank Systems § 265.199 Special requirements for incompatible wastes. (a... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Special requirements for incompatible wastes. 265.199 Section 265.199 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED...

Downregulation of miR-199b promotes the acute spinal cord injury through IKKβ-NF-κB signaling pathway activating microglial cells

Energy Technology Data Exchange (ETDEWEB)

Zhou, Heng-Jun [Department of Neurosurgery, the First Affiliated Hospital, Zhejiang University, 79 Qingchun Road, Hangzhou 310003, Zhejiang (China); Wang, Li-Qing [Department of Anesthesia, the First Affiliated Hospital, Zhejiang University, Hangzhou 310003 (China); Xu, Qing-Sheng; Fan, Zuo-Xu; Zhu, Yu; Jiang, Hao; Zheng, Xiu-Jue; Ma, Yue-Hui [Department of Neurosurgery, the First Affiliated Hospital, Zhejiang University, 79 Qingchun Road, Hangzhou 310003, Zhejiang (China); Zhan, Ren-Ya, E-mail: zhanry148@163.com [Department of Neurosurgery, the First Affiliated Hospital, Zhejiang University, 79 Qingchun Road, Hangzhou 310003, Zhejiang (China)

2016-11-15

Inflammatory response played an important role in the progression of spinal cord injury (SCI). Several miRNAs were associated with the pathology of SCI. However, the molecular mechanism of miRNA involving in inflammatory response in acute SCI (ASCI) was poorly understood. Sprague-Dawley (SD) rats were divided into 2 groups: control group (n=6) and acute SCI (ASCI) group (n=6). The expression of miR-199b and IκB kinase β-nuclear factor-kappa B (IKKβ-NF-κB) signaling pathway were evaluated by quantitative reverse transcription-PCR (qRT-PCR) in rats with ASCI and in primary microglia activated by lipopolysaccharide (LPS). We found that downregulation of miR-199b and activation of IKKβ/NF-κB were observed in rats after ASCI and in activated microglia. miR-199b negatively regulated IKKβ by targeting its 3′- untranslated regions (UTR) through using luciferase reporter assay. Overexpression of miR-199b reversed the up-regulation of IKKβ, p-p65, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in LPS-treated BV2 cells assessed by western blotting analysis. In addition, BMS-345541 reversed the up-regulation effects of miR-199b inhibitor on the expression of TNF-α and IL-1β. In the SCI rats, overexpression of miR-199b attenuated ASCI and decreased the expression of IKKβ-NF-κB signaling pathway and TNF-α and IL-1β. These results indicated that miR-199b attenuated ASCI at least partly through IKKβ-NF-κB signaling pathway and affecting the function of microglia. Our findings suggest that miR-199b may be employed as therapeutic for spinal cord injury. - Highlights: • Downregulation of miR-199b and activation of IKKβ/NF-κB were observed in rat after SCI. • miR-199b negatively regulated IKKβ by targeting its 3′-UTR. • miR-199b overexpression reversed the increasing IKKβ, p-p65, TNF-α and IL-1β in LPS-treated BV2. • BMS-345541 reversed the up-regulation of TNF-α and IL-1β induced by miR-199b inhibitor. • Overexpression of miR-199b

Mercury Report-Children's exposure to elemental mercury

Science.gov (United States)

... gov . Mercury Background Mercury Report Additional Resources Mercury Report - Children's Exposure to Elemental Mercury Recommend on Facebook ... I limit exposure to mercury? Why was the report written? Children attending a daycare in New Jersey ...

TH-B-204-03: TG-199: Implanted Markers for Radiation Treatment Verification

International Nuclear Information System (INIS)

Wang, Z.

2016-01-01

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRI compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant

TH-B-204-03: TG-199: Implanted Markers for Radiation Treatment Verification

Energy Technology Data Exchange (ETDEWEB)

Wang, Z. [Duke University Medical Center (United States)

2016-06-15

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRI compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant

miR-199a-5p Is upregulated during fibrogenic response to tissue injury and mediates TGFbeta-induced lung fibroblast activation by targeting caveolin-1.

Directory of Open Access Journals (Sweden)

Christian Lacks Lino Cardenas

Full Text Available As miRNAs are associated with normal cellular processes, deregulation of miRNAs is thought to play a causative role in many complex diseases. Nevertheless, the precise contribution of miRNAs in fibrotic lung diseases, especially the idiopathic form (IPF, remains poorly understood. Given the poor response rate of IPF patients to current therapy, new insights into the pathogenic mechanisms controlling lung fibroblasts activation, the key cell type driving the fibrogenic process, are essential to develop new therapeutic strategies for this devastating disease. To identify miRNAs with potential roles in lung fibrogenesis, we performed a genome-wide assessment of miRNA expression in lungs from two different mouse strains known for their distinct susceptibility to develop lung fibrosis after bleomycin exposure. This led to the identification of miR-199a-5p as the best miRNA candidate associated with bleomycin response. Importantly, miR-199a-5p pulmonary expression was also significantly increased in IPF patients (94 IPF versus 83 controls. In particular, levels of miR-199a-5p were selectively increased in myofibroblasts from injured mouse lungs and fibroblastic foci, a histologic feature associated with IPF. Therefore, miR-199a-5p profibrotic effects were further investigated in cultured lung fibroblasts: miR-199a-5p expression was induced upon TGFβ exposure, and ectopic expression of miR-199a-5p was sufficient to promote the pathogenic activation of pulmonary fibroblasts including proliferation, migration, invasion, and differentiation into myofibroblasts. In addition, we demonstrated that miR-199a-5p is a key effector of TGFβ signaling in lung fibroblasts by regulating CAV1, a critical mediator of pulmonary fibrosis. Remarkably, aberrant expression of miR-199a-5p was also found in unilateral ureteral obstruction mouse model of kidney fibrosis, as well as in both bile duct ligation and CCl4-induced mouse models of liver fibrosis, suggesting that

Insights into Mercury's Core Evolution from the Thermodynamic Properties of Fe-S-Si

Science.gov (United States)

Edgington, A.; Vocadlo, L.; Stixrude, L. P.; Wood, I. G.; Lord, O. T.

2015-12-01

The structure, composition and evolution of Mercury, the innermost planet, are puzzling, as its high uncompressed density implies a body highly enriched in metallic iron, whilst the existence of Mercury's magnetic field and observations of its longitude librations [1] suggest at least a partially molten core. This study uses a combination of experimental and ab-initio computer simulation techniques to determine the properties of Fe-S-Si (relative atomic percentages, 80:10:10) throughout the conditions of the interior of the planet Mercury, and evaluates the implications of this material for the structure and evolution of the planet's core. Previous studies have considered the addition of sulphur to the pure iron system, as this can significantly depress the melting curve of iron, and so may possibly allow Mercury's core to remain molten to the present day [2]. However, important constraints placed by the MESSENGER spacecraft on Mercury's surface abundance of iron [3] suggest that the planet formed in highly reduced conditions, in which significant amounts of silicon could have also dissolved into the core [4]. First-principles molecular dynamics simulations of the thermodynamic properties of liquid Fe-S-Si, alongside laser-heated diamond-anvil-cell experiments to determine the melting behaviour of the same composition, reveal the slopes of the adiabatic gradient and melting curve respectively, which together may allow insight into the evolution of our solar system's smallest planet. [1] Margot, J. L. et al. (2007) Science, 316: 710-714[2] Schubert, G. et al. (1988) in 'Mercury' 429-460[3] Nittler, L. R. et al. (2011) Science, 333, 1847-1850[4] Malavergne, V. et al. (2010) Icarus, 206:199-209

22 CFR 19.9 - Pension benefits for former spouses.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Pension benefits for former spouses. 19.9 Section 19.9 Foreign Relations DEPARTMENT OF STATE PERSONNEL BENEFITS FOR SPOUSES AND FORMER SPOUSES OF PARTICIPANTS IN THE FOREIGN SERVICE RETIREMENT AND DISABILITY SYSTEM § 19.9 Pension benefits for former spouses. ...

46 CFR 199.70 - Personal lifesaving appliances.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Personal lifesaving appliances. 199.70 Section 199.70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LIFESAVING APPLIANCES AND ARRANGEMENTS... appliances. (a) Lifebuoys. Each vessel must carry lifebuoys approved under approval series 160.150 as follows...

Micro pit formation by mercury-sphere collision

International Nuclear Information System (INIS)

Ishikura, Syuichi; Kogawa, Hiroyuki; Futakawa, Masatoshi; Kaminaga, Masanori; Hino, Ryutaro

2004-01-01

The development of a MW-class spallation neutron source facility is being carried out under the Japan Proton Accelerator Research Complex (J-PARC) Project promoted by JAERI and KEK. A mercury target working as the spallation neutron source will be subjected to pressure waves generated by rapid thermal expansion of mercury due to a pulsed proton beam injection. The pressure wave will impose dynamic stress on the vessel and deform the vessel, which would cause cavitation in mercury. To evaluate the effect of mercury micro jets, driven by cavitation bubble collapse, on the micro-pit formation, analyses on mercury sphere collision were carried out: single bubble dynamics and collision behavior on interface between liquid and solid, which take the nonlinearity due to shock wave in mercury and the strain rate dependency of yield stress in solid metal into account. Analytical results give a good explanation to understand relationship between the micro-pit formation and material properties: the pit size could decrease with increasing the yield strength of materials. (author)

A (201)Hg+ Comagnetometer for (199)Hg+ Trapped Ion Space Atomic Clocks

Science.gov (United States)

Burt, Eric A.; Taghavi, Shervin; Tjoelker, Robert L.

2011-01-01

A method has been developed for unambiguously measuring the exact magnetic field experienced by trapped mercury ions contained within an atomic clock intended for space applications. In general, atomic clocks are insensitive to external perturbations that would change the frequency at which the clocks operate. On a space platform, these perturbative effects can be much larger than they would be on the ground, especially in dealing with the magnetic field environment. The solution is to use a different isotope of mercury held within the same trap as the clock isotope. The magnetic field can be very accurately measured with a magnetic-field-sensitive atomic transition in the added isotope. Further, this measurement can be made simultaneously with normal clock operation, thereby not degrading clock performance. Instead of using a conventional magnetometer to measure ambient fields, which would necessarily be placed some distance away from the clock atoms, first order field-sensitive atomic transition frequency changes in the atoms themselves determine the variations in the magnetic field. As a result, all ambiguity over the exact field value experienced by the atoms is removed. Atoms used in atomic clocks always have an atomic transition (often referred to as the clock transition) that is sensitive to magnetic fields only in second order, and usually have one or more transitions that are first-order field sensitive. For operating parameters used in the (199)Hg(+) clock, the latter can be five orders of magnitude or more sensitive to field fluctuations than the clock transition, thereby providing an unambiguous probe of the magnetic field strength.

Mercury as the Unaccreted Projectile: Thermal Consequences

Science.gov (United States)

Asphaug, Erik; Gabriel, Travis; Jackson, Alan; Perera, Viranga

2017-10-01

Mercury retained substantial volatiles during its formation, in far greater proportion than the Moon, despite losing ~2/3 of its rocky mantle. Its volatile-rich geochemistry would contraindicate a giant impact because it would drive away the volatiles, as in the hypothesis for the Moon. However, the thermal consequences of Mercury formation vary considerably between the two giant impact scenarios, ‘direct hit’ (DH; Benz et al. 1989) and ‘hit and run’ (HR; Asphaug and Reufer 2014). Each begins with a differentiated chondritic proto-Mercury (PM) a bit larger than Mars. In DH, PM gets eroded by a very energetic impactor half its mass, at ~6-7 times the escape velocity. To remove half of PM’s mantle, the post-impact target gets completely shock-vaporized and is sheared apart into space. The bound remnant in DH would experience a comparable deposition of shock enthalpy, as in Moon formation, and would expand into a much larger volume of heliocentric space, leading to a dry planet. The bound remnant will go on to re-accrete much of the silicate mantle that it just lost, another challenge for DH. In HR, PM is the projectile that slams into a terrestrial planet twice its size (proto-Venus or proto-Earth). For typical impact angle and speed, a typical outcome is to ‘bounce”. But for HR to explain Mercury, PM must avoid accretion every time it encounters the target, until it is scattered or migrates away (or is accreted, in which case there is no Mercury), leading to multi-HR scenarios. Tides are intense in HR because the projectile grazes the target core; gravity does most of the work of mantle stripping. Shocks play a secondary role. Whereas in DH the impactor blasts the target inside-out, in HR the runner emerges relatively unshocked, and undispersed except for losing the gravitationally-unbound material. HR is a mechanism for collecting low-shocked remnants, because the intensely shocked material ends up bound to the target or escaping to heliocentric space

12 CFR 19.9 - Ex parte communications.

Science.gov (United States)

2010-01-01

... parte communication means any material oral or written communication relevant to the merits of an... communication is oral, a memorandum stating the substance of the communication) to be placed on the record of... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Ex parte communications. 19.9 Section 19.9...

Safety-technical lay-out of the operational environment of a high-power spallation target system of the megawatt class with mercury as target material

International Nuclear Information System (INIS)

Butzek, M.

2005-06-01

This thesis is concerning the safety relevant layout of the environment of a mercury based 5-Megawatt-spallation target. All safety relevant aspects related to construction, operation and dismantling as well as economical issues were taken into account. Safety concerns are basically driven by the toxic and radioactive inventory as well as the kind and intensity of radiation produced by the spallation process. Due to significant differences in inventory and radiation between a spallation source and a fission reactor, for the design of the spallation source mentioned above the safety philosophy of a fission reactor must not be used unchanged. Rather than this a systematic study of all safety related boundary conditions is necessary. Within this thesis all safety relevant boundary conditions for this specific type of machine are given. Beside the spatial distribution of different areas inside the target station, influence of medias to be used as well as arising radiation and handling requirements are discussed in detail. A general layout of the target station is presented, serving as a basis for all further component and system development. An enclosure concept for the target station was developed, taking into account the safety relevant issues concerning the mercury used as target materials, the water cooling loops containing massive amounts of tritium as well as the materials used for the moderators potentially forming explosive mixtures. Concept and detailed technical layout of the enclosure system was chosen to guarantee safe operation of the source as well as taking care of requirement arising for handling needs. For design of the shielding different suitable materials have been discussed. A design for assembling the shielding is shown taking into account the safety relevant requirements during operation as well as during dismantling. The neutron beam shutters, buried inside the shielding were designed to optimize handling and positioning issued of the inner part

Mercury

Science.gov (United States)

Mercury is an element that is found in air, water and soil. It has several forms. Metallic mercury is a shiny, silver-white, odorless liquid. If ... with other elements to form powders or crystals. Mercury is in many products. Metallic mercury is used ...

Gigacycle fatigue behaviour of austenitic stainless steels used for mercury target vessels

International Nuclear Information System (INIS)

Naoe, Takashi; Xiong, Zhihong; Futakawa, Masatoshi

2016-01-01

A mercury enclosure vessel for the pulsed spallation neutron source manufactured from a type 316L austenitic stainless steel, a so-called target vessel, suffers the cyclic loading caused by the proton beam induced pressure waves. A design criteria of the JSNS target vessel which is defined based on the irradiation damage is 2500 h at 1 MW with a repetition rate of 25 Hz, that is, the target vessel suffers approximately 10 9 cyclic loading while in operation. Furthermore, strain rate of the beam window of the target vessel reaches 50 s −1 at the maximum, which is much higher than that of the conventional fatigue. Gigacycle fatigue strength up to 10 9 cycles for solution annealed 316L (SA) and cold-worked 316L (CW) were investigated through the ultrasonic fatigue tests. Fatigue tests were performed under room temperature and 250 °C which is the maximum temperature evaluated at the beam window in order to investigate the effect of temperature on fatigue strength of SA and CW 316L. The results showed that the fatigue strength at 250 °C is clearly reduced in comparison with room temperature, regardless of cold work level. In addition, residual strength and microhardness of the fatigue tested specimen were measured to investigate the change in mechanical properties by cyclic loading. Cyclic hardening was observed in both the SA and CW 316L, and cyclic softening was observed in the initial stage of cyclic loading in CW 316L. Furthermore, abrupt temperature rising just before fatigue failure was observed regardless of testing conditions.

TH-B-204-00: Implanted Markers for Radiation Therapy and TG 199 Update

International Nuclear Information System (INIS)

2016-01-01

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRI compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant

TH-B-204-00: Implanted Markers for Radiation Therapy and TG 199 Update

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-06-15

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRI compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant

Human Exposure and Health Effects of Inorganic and Elemental Mercury

Science.gov (United States)

Zheng, Wei

2012-01-01

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety. PMID:23230464

37 CFR 1.99 - Third-party submission in published application.

Science.gov (United States)

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Third-party submission in published application. 1.99 Section 1.99 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND... Provisions Information Disclosure Statement § 1.99 Third-party submission in published application. (a) A...

Natural stable isotopic compositions of mercury in aerosols and wet precipitations around a coal-fired power plant in Xiamen, southeast China

Science.gov (United States)

Huang, Shuyuan; Sun, Lumin; Zhou, Tingjin; Yuan, Dongxing; Du, Bing; Sun, Xiuwu

2018-01-01

In this study, samples of 18 wet precipitations (WPs) and 38 aerosols were collected around a coal-fired power plant (CFPP) located in Xiamen, southeast China, which was equipped with a seawater flue gas desulfurization system. Total particulate mercury (TPM) in aerosol samples, and total mercury (WP-TM), dissolved mercury (WP-DM) and particulate mercury (WP-PM) in WP samples were analyzed for the natural isotopic compositions of mercury. For the first time, both mass dependent fractionation (MDF) and mass independent fractionation of odd (odd-MIF) and even (even-MIF) isotopes of WP-DM and WP-PM were reported and discussed. Both WP-TM and TPM displayed negative MDF and slightly positive even-MIF. Negative odd-MIF was observed in TPM and WP-PM, whereas positive odd-MIF was observed in WP-TM and WP-DM. It was found that the mercury budget in WP-PM samples was mainly controlled by atmospheric particles. Potential sources of mercury in samples were identified via analysis of mercury isotopic signatures and meteorological data with the NOAA HYSPLIT model. The results showed that TPM and WP-PM in solid samples were homologous and the isotopic compositions of WP-TM depended on those of WP-DM. The ratios of Δ199Hg/Δ201Hg resulting from photochemical reactions and positive Δ200Hg values (from -0.06‰ to 0.27‰) in all samples indicated that the mercury coming from local emission of the CFPP together with long-distance transportation were the two main contributing sources.

Got Mercury?

Science.gov (United States)

Meyers, Valerie E.; McCoy, J. Torin; Garcia, Hector D.; James, John T.

2009-01-01

Many of the operational and payload lighting units used in various spacecraft contain elemental mercury. If these devices were damaged on-orbit, elemental mercury could be released into the cabin. Although there are plans to replace operational units with alternate light sources, such as LEDs, that do not contain mercury, mercury-containing lamps efficiently produce high quality illumination and may never be completely replaced on orbit. Therefore, exposure to elemental mercury during spaceflight will remain possible and represents a toxicological hazard. Elemental mercury is a liquid metal that vaporizes slowly at room temperature. However, it may be completely vaporized at the elevated operating temperatures of lamps. Although liquid mercury is not readily absorbed through the skin or digestive tract, mercury vapors are efficiently absorbed through the respiratory tract. Therefore, the amount of mercury in the vapor form must be estimated. For mercury releases from lamps that are not being operated, we utilized a study conducted by the New Jersey Department of Environmental Quality to calculate the amount of mercury vapor expected to form over a 2-week period. For longer missions and for mercury releases occurring when lamps are operating, we conservatively assumed complete volatilization of the available mercury. Because current spacecraft environmental control systems are unable to remove mercury vapors, both short-term and long-term exposures to mercury vapors are possible. Acute exposure to high concentrations of mercury vapors can cause irritation of the respiratory tract and behavioral symptoms, such as irritability and hyperactivity. Chronic exposure can result in damage to the nervous system (tremors, memory loss, insomnia, etc.) and kidneys (proteinurea). Therefore, the JSC Toxicology Group recommends that stringent safety controls and verifications (vibrational testing, etc.) be applied to any hardware that contains elemental mercury that could yield

Analysis of the AGS experiment on a mercury target with a moderator and a lead reflector bombarded by GeV energy protons

International Nuclear Information System (INIS)

Maekawa, Fujio; Meigo, Shin-ichiro; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro; Ino, Takashi; Sato, Setsuo

2001-01-01

The AGS experiment on a mercury target with a moderator and a lead reflector bombarded by GeV energy protons was analyzed to investigate prediction capability of Monte Carlo simulation codes used in neutronic designs of spallation neutron sources. The NMTC/JAM code was used for nucleon meson transport calculations above 20 MeV while the MCNP-4A code with the JENDL cross section library was used for neutron transport below 20 MeV. The MCNPX code with the LA-150 library was also used for a reference. The calculations were compared with the experimental data obtained with 1.94, 12 and 24 GeV proton beams: (1) neutron flux distributions along the mercury target and (2) spectral fluxes of thermal neutrons extracted from a light water moderator. As a result, it was found that all the calculations predicted these experimental results with accuracies better than ±50% in absolute values. Accordingly, it was concluded that these calculation codes were adequate for neutronics designs of spallation neutron sources. (author)

Disposal strategy of proton irradiated mercury from high power spallation sources

International Nuclear Information System (INIS)

Chiriki, Suresh

2010-01-01

Large spallation sources are intended to be constructed in Europe (EURISOL: nuclear physics research facility and ESS: European Spallation Source). These facilities would accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Liquid waste cannot be tolerated in European repositories. As part of this work on safety/decommissioning of high-power spallation sources, our investigations were focused mainly to study experimentally and theoretically the solidification of liquid mercury waste (selection of an adequate solid mercury form and of an immobilization matrix, chemical engineering process studies on solidification/stabilization and on encapsulating in a matrix). Based on experimental results and supported by literature Hg-chalcogens (HgS, HgSe) will be more stable in repositories than amalgams. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in possible accidents with water ingress in a repository. Additionally immobilization of mercury in a cement matrix and polysiloxane matrix were tested. HgS formation from liquid target mercury by a wet process is identified as a suitable formation procedure. These investigations reveal that an almost 99.9% elementary Hg conversion can be achieved and that wet process can be reasonably handled under hot cell conditions. (orig.)

Disposal strategy of proton irradiated mercury from high power spallation sources

Energy Technology Data Exchange (ETDEWEB)

Chiriki, Suresh

2010-07-01

Large spallation sources are intended to be constructed in Europe (EURISOL: nuclear physics research facility and ESS: European Spallation Source). These facilities would accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Liquid waste cannot be tolerated in European repositories. As part of this work on safety/decommissioning of high-power spallation sources, our investigations were focused mainly to study experimentally and theoretically the solidification of liquid mercury waste (selection of an adequate solid mercury form and of an immobilization matrix, chemical engineering process studies on solidification/stabilization and on encapsulating in a matrix). Based on experimental results and supported by literature Hg-chalcogens (HgS, HgSe) will be more stable in repositories than amalgams. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in possible accidents with water ingress in a repository. Additionally immobilization of mercury in a cement matrix and polysiloxane matrix were tested. HgS formation from liquid target mercury by a wet process is identified as a suitable formation procedure. These investigations reveal that an almost 99.9% elementary Hg conversion can be achieved and that wet process can be reasonably handled under hot cell conditions. (orig.)

Fractionation of mercury stable isotopes during coal combustion and seawater flue gas desulfurization

International Nuclear Information System (INIS)

Huang, Shuyuan; Yuan, Dongxing; Lin, Haiying; Sun, Lumin; Lin, Shanshan

2017-01-01

In the current study, fractionation of mercury isotopes during coal combustion and seawater flue gas desulfurization (SFGD) in a coal-fired power plant using a SFGD system was investigated. Fourteen samples were collected from the power plant. The samples were pretreated with a combustion-trapping method and were analyzed with a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS). Compared with the raw coal, the bottom ash was enriched with lighter mercury isotopes with δ 202 Hg values ranging from −0.45 to −0.03‰. The fly ash was enriched with lighter mercury isotopes with δ 202 Hg values ranging from −1.49 to −0.73‰ for Chinese coal and from −1.47 to −0.62‰ for Indonesian coal. The δ 202 Hg of fresh seawater and desulfurized seawater was found to be −1.32 and −0.32‰ respectively. These δ 202 Hg values indicated that the desulfurized seawater was enriched with heavier mercury isotopes. Based upon the calculated results obtained from the mass balance equation, it was suggested that the stack emissions were enriched with lighter mercury isotopes. Mass independent fractionation was observed in most of the samples with a Δ 199 Hg/Δ 201 Hg ratio of approximately 0.96. The results help in improving the understanding of mercury isotope fractionation during coal combustion and SFGD, and are also useful in tracing the mercury emissions from coal fired power plants. - Highlights: • Spread of 1.5‰ was observed in δ 202 Hg values of raw coals and coal related samples. • The δ 202 Hg values were more negative in fly ash than those in the raw coal. • The flue gas had a significant Hg fractionation after desulfurization. • The stack emissions were enriched with lighter isotopes compared with the raw coal.

Mercury flow tests (first report). Wall friction factor measurement tests and future tests plan

International Nuclear Information System (INIS)

Kaminaga, Masanori; Kinoshita, Hidetaka; Haga, Katsuhiro; Hino, Ryutaro; Sudo, Yukio

1999-07-01

In the neutron science project at JAERI, we plan to inject a pulsed proton beam of a maximum power of 5 MW from a high intense proton accelerator into a mercury target in order to produce high energy neutrons of a magnitude of ten times or more than existing facilities. The neutrons produced by the facility will be utilized for advanced field of science such as the life sciences etc. An urgent issue in order to accomplish this project is the establishment of mercury target technology. With this in mind, a mercury experimental loop with the capacity to circulate mercury up to 15 L/min was constructed to perform thermal hydraulic tests, component tests and erosion characteristic tests. A measurement of the wall friction factor was carried out as a first step of the mercury flow tests, while testing the characteristic of components installed in the mercury loop. This report presents an outline of the mercury loop and experimental results of the wall friction factor measurement. From the wall friction factor measurement, it was made clear that the wettability of the mercury was improved with an increase of the loop operation time and at the same time the wall friction factors were increased. The measured wall friction factors were much lower than the values calculated by the Blasius equation at the beginning of the loop operation because of wall slip caused by a non-wetted condition. They agreed well with the values calculated by the Blasius equation within a deviation of 10% when the sum of the operation time increased more than 11 hours. This report also introduces technical problems with a mercury circulation and future tests plan indispensable for the development of the mercury target. (author)

Quantifying mercury isotope dynamics in captive Pacific bluefin tuna (Thunnus orientalis

Directory of Open Access Journals (Sweden)

Sae Yun Kwon

2016-02-01

Full Text Available Abstract Analyses of mercury (Hg isotope ratios in fish tissues are used increasingly to infer sources and biogeochemical processes of Hg in natural aquatic ecosystems. Controlled experiments that can couple internal Hg isotope behavior with traditional isotope tracers (δ13C, δ15N can improve the applicability of Hg isotopes as natural ecological tracers. In this study, we investigated changes in Hg isotope ratios (δ202Hg, Δ199Hg during bioaccumulation of natural diets in the pelagic Pacific bluefin tuna (Thunnus orientalis; PBFT. Juvenile PBFT were fed a mixture of natural prey and a dietary supplement (60% Loligo opalescens, 31% Sardinops sagax, 9% gel supplement in captivity for 2914 days, and white muscle tissues were analyzed for Hg isotope ratios and compared to time in captivity and internal turnover of δ13C and δ15N. PBFT muscle tissues equilibrated to Hg isotope ratios of the dietary mixture within ∼700 days, after which we observed a cessation in further shifts in Δ199Hg, and small but significant negative δ202Hg shifts from the dietary mixture. The internal behavior of Δ199Hg is consistent with previous fish studies, which showed an absence of Δ199Hg fractionation during Hg bioaccumulation. The negative δ202Hg shifts can be attributed to either preferential excretion of Hg with higher δ202Hg values or individual variability in captive PBFT feeding preferences and/or consumption rates. The overall internal behavior of Hg isotopes is similar to that described for δ13C and δ15N, though observed Hg turnover was slower compared to carbon and nitrogen. This improved understanding of internal dynamics of Hg isotopes in relation to δ13C and δ15N enhances the applicability of Hg isotope ratios in fish tissues for tracing Hg sources in natural ecosystems.

Foil analysis of 1.5-GeV proton bombardment of a mercury target

CERN Document Server

Charlton, L A; Glasgow, D C; Gabriel, T A

1999-01-01

The number of reactant nuclei in a series of foils surrounding a container of mercury that has been bombarded by 1.5-GeV protons is calculated and compared with experimental measurements. This procedure is done to aid in the validation of the mercury cross sections used in the design studies of the Spallation Neutron Source (SNS). It is found that the calculations match the measurements to within the uncertainties inherent in the analysis.

7 CFR 800.199 - Conflict-of-interest provisions.

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Conflict-of-interest provisions. 800.199 Section 800... Delegations, Designations, Approvals, Contracts, and Conflicts of Interest § 800.199 Conflict-of-interest...) Prohibited conflicts of interest. Unless waived on a case-by-case basis by the Administrator under section 11...

CA19-9: A promising tumor marker for pancreatic carcinoma

International Nuclear Information System (INIS)

Sakahara, H.; Endo, K.; Nakajima, K.; Hidaka, A.; Nakashima, T.; Ohta, H.; Torizuka, K.; Naito, A.; Suzuki, T.

1984-01-01

In order to evaluate CA19-9 as a tumor marker for pancreatic carcinoma (PC), serum levels of CA19-9 were compared with those of CEA and elastase-1 in 56 patients, consisted of 43 cases with histologically proven adenocarcinomas and 13 cases with chronic pancreatitis. Serum levels were determined by using RIA kit obtained from CIS, France (CA19-9 and CEA) and Abbot (elastase-1). CA19-9 gave the highest accuracy among tumor markers the authors have studied and serum levels were markedly elevated over 100U/ml in 30 (70%) cases with PC, whereas none in chronic pancreatitis. CA19-9 values were closely related to the tumor size and the presence or absence of metastsis on CT findings. Small tumors of less than 3cm in diameter, although the site of tumor was limited to the head of the pancreas, showed positive results in 2 out of 5 cases. Furthermore, CA19-9 was at a level of less than 22U/ml in 98 normal controls and was found to be elevated in only 4 (3%) out of 124 patients with benign diseases, including liver diseases, gastric ulcer, cholelithiasis, and so on. These results indicate that CA19-9 is much better in diagnosis and management of PC than is CEA

46 CFR 199.130 - Stowage of survival craft.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 199.130 Section 199.130... craft. (a) General. Each survival craft must be stowed— (1) As close to the accommodation and service spaces as possible; (2) So that neither the survival craft nor its stowage arrangements will interfere...

Elevated serum ferritin and mercury concentrations are associated with hypertension; analysis of the fourth and fifth Korea national health and nutrition examination survey (KNHANES IV-2, 3, 2008-2009 and V-1, 2010).

Science.gov (United States)

Choi, Beomhee; Yeum, Kyung-Jin; Park, Soo-Jung; Kim, Kyu-Nam; Joo, Nam-Seok

2015-01-01

The impact of simultaneously elevated serum ferritin and mercury concentrations on hypertension in the general population is not known. To determine the association of serum ferritin and mercury concentrations with hypertension, 6213 subjects (3060 men and 3153 women) over 20 years of age from 2008 to 2010 Korea National Health and Nutrition Examination Survey were divided into tertiles according to serum ferritin and mercury concentrations in each gender. Serum ferritin (258.2 vs. 94.8 pmol/L) and mercury concentrations (28.4 vs. 19.9 nmol/L) were higher in men than in women. Serum ferritin (men; P = 0.029, women; P mercury (men; P mercury concentrations in both men (r = 0.193, P mercury tertiles increased after proper adjustments. Furthermore, significantly higher odds ratios of hypertension were found in the second (OR = 1.86, 95% CI; 1.05-3.30), and third (OR = 1.84, 95% CI; 1.01-3.36) tertiles of serum ferritin with the top tertile of serum mercury in men. The current study indicate that serum ferritin and mercury concentrations are associated with the prevalence of hypertension and that simultaneously elevated serum ferritin and mercury concentrations are related to the risk for hypertension in men. © 2013 The Authors. The Environmental Toxicology published by Wiley Periodicals, Inc.

Planet Mercury

Science.gov (United States)

1974-01-01

Mariner 10's first image of Mercury acquired on March 24, 1974. During its flight, Mariner 10's trajectory brought it behind the lighted hemisphere of Mercury, where this image was taken, in order to acquire important measurements with other instruments.This picture was acquired from a distance of 3,340,000 miles (5,380,000 km) from the surface of Mercury. The diameter of Mercury (3,031 miles; 4,878 km) is about 1/3 that of Earth.Images of Mercury were acquired in two steps, an inbound leg (images acquired before passing into Mercury's shadow) and an outbound leg (after exiting from Mercury's shadow). More than 2300 useful images of Mercury were taken, both moderate resolution (3-20 km/pixel) color and high resolution (better than 1 km/pixel) black and white coverage.

Assessment of Mercury in Fish Tissue from Select Lakes of Northeastern Oregon

Science.gov (United States)

A fish tissue study was conducted in five northeastern Oregon reservoirs to evaluate mercury concentrations in an area where elevated atmospheric mercury deposition had been predicted by a national EPA model, but where tissue data were sparse. The study targeted resident predator...

Multi-weight isotherm results for mercury removal in upper East Fork Popular Creek water

International Nuclear Information System (INIS)

Bostick, D.A.; Klasson, K.T.

1998-02-01

Many sorbents have been developed for the removal of mercury and heavy metals from waters; however, the majority of data published to date do not address the removal of mercury to the target levels represented in this project. The application to which these sorbents are targeted for use is the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Sorbents with thiouronium, thiol, amine, sulfur, and proprietary functional groups were selected for these studies. The initial mercury content in the majority of the batch samples was significantly augmented so that the equilibrium concentration was similar to that found in the original stream sample for at least one sample. Mercury was successfully removed from actual water via adsorption onto Ionac SR-4 (by Sybron Chemicals, Inc.), Keyle:X (by SolmeteX), and Mersorb (by Nucon International, Inc.) resins to levels below the target goal of 12 ng/L. A thiol-based resin (Ionac SR-4) performed the best, indicating that over 200,000 volumes of water could be treated with one volume of resin. The cost of the resin is approximately $0.24 per 1000 gal of water

Studies on the preparation of thallium-201 by irradiating mercury with protons using extraction chromatography technique to separate thallium from mercury

International Nuclear Information System (INIS)

Fernandes, L.

1990-01-01

Radionuclide sup(201)Tl is used in Nuclear Medicine to identify myocardial ischemia or myocardial infarct. It is a cyclotron-produced radioisotope, obtained indirectly from the decay of sup(202)Pb or directly by irradiating mercury with deuterons or protons. The usual technique to prepare sup(201)Tl makes use of the nuclear reaction: sup(203)(p,3n) → sup(201)Tl, which requires proton energy of around 28 MeV. Due to the limited proton energy of IPEN'S CV-28 cyclotron, studies on the irradiating conditions of natural mercury oxide pellets and drops of natural mercury metal were made in the range of 19 - 24 MeV. At the end of the bombardment of a 6 MeV thickness target of natural mercury metal with 19 MeV protons around 10 MBq sup(201)Tl/μ A h was obtained. (author)

Mercury

NARCIS (Netherlands)

de Vries, Irma

2017-01-01

Mercury is a naturally occurring metal that exists in several physical and chemical forms. Inorganic mercury refers to compounds formed after the combining of mercury with elements such as chlorine, sulfur, or oxygen. After combining with carbon by covalent linkage, the compounds formed are called

MiRNA-199a-3p Regulates C2C12 Myoblast Differentiation through IGF-1/AKT/mTOR Signal Pathway

Directory of Open Access Journals (Sweden)

Long Jia

2013-12-01

Full Text Available MicroRNAs constitute a class of ~22-nucleotide non-coding RNAs. They modulate gene expression by associating with the 3' untranslated regions (3' UTRs of messenger RNAs (mRNAs. Although multiple miRNAs are known to be regulated during myoblast differentiation, their individual roles in muscle development are still not fully understood. In this study, we showed that miR-199a-3p was highly expressed in skeletal muscle and was induced during C2C12 myoblasts differentiation. We also identified and confirmed several genes of the IGF-1/AKT/mTOR signal pathway, including IGF-1, mTOR, and RPS6KA6, as important cellular targets of miR-199a-3p in myoblasts. Overexpression of miR-199a-3p partially blocked C2C12 myoblast differentiation and the activation of AKT/mTOR signal pathway, while interference of miR-199a-3p by antisense oligonucleotides promoted C2C12 differentiation and myotube hypertrophy. Thus, our studies have established miR-199a-3p as a potential regulator of myogenesis through the suppression of IGF-1/AKT/mTOR signal pathway.

Mercury methylation rates of biofilm and plankton microorganisms from a hydroelectric reservoir in French Guiana.

Science.gov (United States)

Huguet, L; Castelle, S; Schäfer, J; Blanc, G; Maury-Brachet, R; Reynouard, C; Jorand, F

2010-02-15

The Petit-Saut ecosystem is a hydroelectric reservoir covering 365km(2) of flooded tropical forest. This reservoir and the Sinnamary Estuary downstream of the dam are subject to significant mercury methylation. The mercury methylation potential of plankton and biofilm microorganisms/components from different depths in the anoxic reservoir water column and from two different sites along the estuary was assessed. For this, reservoir water and samples of epiphytic biofilms from the trunk of a submerged tree in the anoxic water column and from submerged branches in the estuary were batch-incubated from 1h to 3 months with a nominal 1000ng/L spike of Hg(II) chloride enriched in (199)Hg. Methylation rates were determined for different reservoir and estuarine communities under natural nutrient (reservoir water, estuary freshwater) and artificial nutrient (culture medium) conditions. Methylation rates in reservoir water incubations were the highest with plankton microorganisms sampled at -9.5m depth (0.5%/d) without addition of biofilm components. Mercury methylation rates of incubated biofilm components were strongly enhanced by nutrient addition. The results suggested that plankton microorganisms strongly contribute to the total Hg methylation in the Petit-Saut reservoir and in the Sinnamary Estuary. Moreover, specific methylation efficiencies (%Me(199)Hg(net)/cell) suggested that plankton microorganisms could be more efficient methylating actors than biofilm consortia and that their methylation efficiency may be reduced in the presence of biofilm components. Extrapolation to the reservoir scale of the experimentally determined preliminary methylation efficiencies suggested that plankton microorganisms in the anoxic water column could produce up to 27mol MeHg/year. Taking into account that (i) demethylation probably occurs in the reservoir and (ii) that the presence of biofilm components may limit the methylation efficiency of plankton microorganisms, this result is

A rhizosphere-associated symbiont, Photobacterium spp. strain MELD1, and its targeted synergistic activity for phytoprotection against mercury.

Directory of Open Access Journals (Sweden)

Dony Chacko Mathew

Full Text Available Though heavy metal such as mercury is toxic to plants and microorganisms, the synergistic activity between them may offer benefit for surviving. In this study, a mercury-reducing bacterium, Photobacterium spp. strain MELD1, with an MIC of 33 mg x kg(-1 mercury was isolated from a severely mercury and dioxin contaminated rhizosphere soil of reed (Phragmites australis. While the whole genome sequencing of MELD1 confirmed the presence of a mer operon, the mercury reductase MerA gene showed 99% sequence identity to Vibrio shilloni AK1 and implicates its route resulted from the event of horizontal gene transfer. The efficiency of MELD1 to vaporize mercury (25 mg x kg(-1, 24 h and its tolerance to toxic metals and xenobiotics such as lead, cadmium, pentachlorophenol, pentachloroethylene, 3-chlorobenzoic acid, 2,3,7,8-tetrachlorodibenzo-p-dioxin and 1,2,3,7,8,9-hexachlorodibenzo-p-dioxin is promising. Combination of a long yard bean (Vigna unguiculata ssp. Sesquipedalis and strain MELD1 proved beneficial in the phytoprotection of mercury in vivo. The effect of mercury (Hg on growth, distribution and tolerance was examined in root, shoot, leaves and pod of yard long bean with and without the inoculation of strain MELD1. The model plant inoculated with MELD1 had significant increases in biomass, root length, seed number, and increased mercury uptake limited to roots. Biolog plate assay were used to assess the sole-carbon source utilization pattern of the isolate and Indole-3-acetic acid (IAA productivity was analyzed to examine if the strain could contribute to plant growth. The results of this study suggest that, as a rhizosphere-associated symbiont, the synergistic activity between the plant and MELD1 can improve the efficiency for phytoprotection, phytostabilization and phytoremediation of mercury.

A rhizosphere-associated symbiont, Photobacterium spp. strain MELD1, and its targeted synergistic activity for phytoprotection against mercury.

Science.gov (United States)

Mathew, Dony Chacko; Ho, Ying-Ning; Gicana, Ronnie Gicaraya; Mathew, Gincy Marina; Chien, Mei-Chieh; Huang, Chieh-Chen

2015-01-01

Though heavy metal such as mercury is toxic to plants and microorganisms, the synergistic activity between them may offer benefit for surviving. In this study, a mercury-reducing bacterium, Photobacterium spp. strain MELD1, with an MIC of 33 mg x kg(-1) mercury was isolated from a severely mercury and dioxin contaminated rhizosphere soil of reed (Phragmites australis). While the whole genome sequencing of MELD1 confirmed the presence of a mer operon, the mercury reductase MerA gene showed 99% sequence identity to Vibrio shilloni AK1 and implicates its route resulted from the event of horizontal gene transfer. The efficiency of MELD1 to vaporize mercury (25 mg x kg(-1), 24 h) and its tolerance to toxic metals and xenobiotics such as lead, cadmium, pentachlorophenol, pentachloroethylene, 3-chlorobenzoic acid, 2,3,7,8-tetrachlorodibenzo-p-dioxin and 1,2,3,7,8,9-hexachlorodibenzo-p-dioxin is promising. Combination of a long yard bean (Vigna unguiculata ssp. Sesquipedalis) and strain MELD1 proved beneficial in the phytoprotection of mercury in vivo. The effect of mercury (Hg) on growth, distribution and tolerance was examined in root, shoot, leaves and pod of yard long bean with and without the inoculation of strain MELD1. The model plant inoculated with MELD1 had significant increases in biomass, root length, seed number, and increased mercury uptake limited to roots. Biolog plate assay were used to assess the sole-carbon source utilization pattern of the isolate and Indole-3-acetic acid (IAA) productivity was analyzed to examine if the strain could contribute to plant growth. The results of this study suggest that, as a rhizosphere-associated symbiont, the synergistic activity between the plant and MELD1 can improve the efficiency for phytoprotection, phytostabilization and phytoremediation of mercury.

A Rhizosphere-Associated Symbiont, Photobacterium spp. Strain MELD1, and Its Targeted Synergistic Activity for Phytoprotection against Mercury

Science.gov (United States)

Mathew, Dony Chacko; Ho, Ying-Ning; Gicana, Ronnie Gicaraya; Mathew, Gincy Marina; Chien, Mei-Chieh; Huang, Chieh-Chen

2015-01-01

Though heavy metal such as mercury is toxic to plants and microorganisms, the synergistic activity between them may offer benefit for surviving. In this study, a mercury-reducing bacterium, Photobacterium spp. strain MELD1, with an MIC of 33 mg . kg-1 mercury was isolated from a severely mercury and dioxin contaminated rhizosphere soil of reed (Phragmites australis). While the whole genome sequencing of MELD1 confirmed the presence of a mer operon, the mercury reductase MerA gene showed 99% sequence identity to Vibrio shilloni AK1 and implicates its route resulted from the event of horizontal gene transfer. The efficiency of MELD1 to vaporize mercury (25 mg . kg-1, 24 h) and its tolerance to toxic metals and xenobiotics such as lead, cadmium, pentachlorophenol, pentachloroethylene, 3-chlorobenzoic acid, 2,3,7,8-tetrachlorodibenzo-p-dioxin and 1,2,3,7,8,9-hexachlorodibenzo-p-dioxin is promising. Combination of a long yard bean (Vigna unguiculata ssp. Sesquipedalis) and strain MELD1 proved beneficial in the phytoprotection of mercury in vivo. The effect of mercury (Hg) on growth, distribution and tolerance was examined in root, shoot, leaves and pod of yard long bean with and without the inoculation of strain MELD1. The model plant inoculated with MELD1 had significant increases in biomass, root length, seed number, and increased mercury uptake limited to roots. Biolog plate assay were used to assess the sole-carbon source utilization pattern of the isolate and Indole-3-acetic acid (IAA) productivity was analyzed to examine if the strain could contribute to plant growth. The results of this study suggest that, as a rhizosphere-associated symbiont, the synergistic activity between the plant and MELD1 can improve the efficiency for phytoprotection, phytostabilization and phytoremediation of mercury. PMID:25816328

49 CFR 173.164 - Mercury (metallic and articles containing mercury).

Science.gov (United States)

2010-10-01

... ounces) of mercury per package; (iv) Tubes which are completely jacketed in sealed leakproof metal cases... 49 Transportation 2 2010-10-01 2010-10-01 false Mercury (metallic and articles containing mercury... Than Class 1 and Class 7 § 173.164 Mercury (metallic and articles containing mercury). (a) For...

[Effects of Citric Acid on Activation and Methylation of Mercury in the Soils of Water-Level-Fluctuating Zone of the Three Gorges.Reservoir].

Science.gov (United States)

Qin, Cai-qing; Liang, Li; You, Rui; Deng, Han; Wang, Ding-yong

2015-12-01

To investigate effects of the main component of vegetation root exudates-citric acid on activation and methylation of mercury in the soil of water-level-fluctuating zone (WLFZ) of the Three Gorges Reservoir area, simulation experiments were conducted by extracting and cultivating soil with different concentrations of citric acid. The results showed that after adding citric acid, the total mercury content in leaching solution before reaching peak were higher than that of the control, and increased with the increase of citric acid concentrations. The maximum amount of mercury complexes increased initially and then reached plateaus with the percentage against the total mercury in soil of 1.03%, 1.67%, 1.99%, 2.47%, 2.68%, 2.73% and 2.73% for different citric acid concentrations (0, 1, 2, 4, 5, 6 and 8 mmol · L⁻¹). In addition, concentrations of methylmercury ( MeHg) in soil remained stable in the first 3 hours, and then increased accompanying with the increasing rate rising with the concentration of citric acid ( besides the control group) . This result indicated that citric acid probably could promote the transformation process from inorganic mercury to MeHg in soil. which increased with the concentration of citric acid.

CFD Validation of Gas Injection in Flowing Mercury over Vertical Smooth and Grooved Wall

International Nuclear Information System (INIS)

Abdou, Ashraf A.; Wendel, Mark W.; Felde, David K.; Riemer, Bernie

2009-01-01

The Spallation Neutron Source (SNS) is an accelerator-based neutron source at Oak Ridge National Laboratory (ORNL). The nuclear spallation reaction occurs when a proton beam hits liquid mercury. This interaction causes thermal expansion of the liquid mercury which produces high pressure waves. When these pressure waves hit the target vessel wall, cavitation can occur and erode the wall. Research and development efforts at SNS include creation of a vertical protective gas layer between the flowing liquid mercury and target vessel wall to mitigate the cavitation damage erosion and extend the life time of the target. Since mercury is opaque, computational fluid dynamics (CFD) can be used as a diagnostic tool to see inside the liquid mercury and guide the experimental efforts. In this study, CFD simulations of three dimensional, unsteady, turbulent, two-phase flow of helium gas injection in flowing liquid mercury over smooth, vertically grooved and horizontally grooved walls are carried out with the commercially available CFD code Fluent-12 from ANSYS. The Volume of Fluid (VOF) model is used to track the helium-mercury interface. V-shaped vertical and horizontal grooves with 0.5 mm pitch and about 0.7 mm depth were machined in the transparent wall of acrylic test sections. Flow visualization data of helium gas coverage through transparent test sections is obtained with a high-speed camera at the ORNL target test facility (TTF). The helium gas mass flow rate is 8 mg/min and introduced through a 0.5 mm diameter port. The local mercury velocity is 0.9 m/s. In this paper, the helium gas flow rate and the local mercury velocity are kept constant for the three cases. Time integration of predicted helium gas volume fraction over time is done to evaluate the gas coverage and calculate the average thickness of the helium gas layer. The predicted time-integrated gas coverage over vertically grooved and horizontally grooved test sections is better than over a smooth wall. The

Recovery of mercury from mercury compounds via electrolytic methods

Science.gov (United States)

Grossman, Mark W.; George, William A.

1988-01-01

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

Concentrations and isotope ratios of mercury in sediments from shelf and continental slope at Campos Basin near Rio de Janeiro, Brazil.

Science.gov (United States)

Araujo, Beatriz Ferreira; Hintelmann, Holger; Dimock, Brian; Almeida, Marcelo Gomes; Rezende, Carlos Eduardo

2017-07-01

Mercury (Hg) may originate from both anthropogenic and natural sources. The measurement of spatial and temporal variations of Hg isotope ratios in sediments may enable source identification and tracking of environmental processes. In this study we establish the distribution of mercury concentrations and mercury isotope ratios in surface sediments of three transects along the continental shelf and slope in Campos Basin-RJ-Brazil. The shelf showed on average lower total Hg concentrations (9.2 ± 5.3 ng g -1 ) than the slope (24.6 ± 8.8 ng g -1 ). MMHg average concentrations of shelf 0.15 ± 0.12 ng g -1 and slope 0.13 ± 0.06 ng g -1 were not significantly different. Distinct differences in Hg isotope ratio signatures were observed, suggesting that the two regions were impacted by different sources of Hg. The shelf showed more negative δ 202 Hg and Δ 199 Hg values ranging from -0.59 to -2.19‰ and from -0.76 to 0.08‰, respectively. In contrast, the slope exhibited δ 202 Hg values from -0.29 to -1.82‰ and Δ 199 Hg values from -0.23 to 0.09‰. Mercury found on the shelf, especially along the "D" and "I" transects, is depleted in heavy isotopes resulting in more negative δ 202 Hg compared to the slope. Isotope ratios observed in the "D" and "I" shelf region are similar to Hg ratios commonly associated with plants and vegetation and very comparable to those detected in the estuary and adjoining mangrove forest, which suggests that Hg exported from rivers may be the dominating source of Hg in near coastal regions along the northern part of the shelf. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multi-MW target station: Beam Window Issues and Transverse Film Target

CERN Document Server

Herrera-Martinez, A

The analysis of the EURISOL-DS Multi_MW target precise geometry has proved that large fission yields can be achieved with a 4 MW, providing a technically feasible design to evacuate the power deposited in the liquid mercury. Different designs for the mercury flow have been proposed, which maintain its temperature below the boiling point with moderate flow speeds (maximum 4 m/s).

Perturbed angular correlation study of the static and dynamic aspects of cadmium and mercury atoms inside and attached to a C{sub 60} fullerene cage

Energy Technology Data Exchange (ETDEWEB)

Das, Satyendra K.; Guin, Rashmohan; Banerjee, Debasish [Variable Energy Cyclotron Centre, Kolkata (India). Accelerator Chemistry Section (Bhabha Atomic Research Centre); Johnston, Karl [CERN, Geneva (Switzerland); Das, Parnika [Variable Energy Cyclotron Centre, Kolkata (India); Butz, Tilman [Leipzig Univ. (Germany). Faculty of Physics and Earth Sciences; Amaral, Vitor S. [Aveiro Univ. (Portugal). Physics Dept.; Aveiro Univ. (Portugal). CICECO; Correia, Joao G.; Barbosa, Marcelo B. [Instituto Tecnologico e Nuclear (ITN), Sacavem (Portugal); CERN, Geneva (Switzerland). ISOLDE

2014-10-15

30 keV {sup 111m}Cd and 50 keV {sup 199m}Hg beams from ISOLDE were used to implant on preformed targets of C{sub 60} with a thickness of 1 mg cm{sup -2}. Endofullerene compounds, viz. {sup 111m}Cd rate at C{sub 60} and {sup 199m}Hg rate at C{sub 60} formed during implantation were separated by filtration through micropore filter paper followed by solvent extraction. Dried samples of the endofullerene compounds were counted for the time differential perturbed angular correlation (TDPAC) measurement using the coincidence of the 151-245keV cascade of {sup 111m}Cd and the 374-158 keV cascade of {sup 199m}Hg on a six LaBr{sub 3}(Ce) detector system coupled with digital electronics. The results for {sup 111m}Cd rate at C{sub 60} indicate a single static component (27 %) and a fast relaxing component (73 %), the latter implying that the cadmium atom moves rapidly inside the cage at room temperature. The quadrupole interaction frequency and asymmetry parameter of the cadmium atom occupying the static site in C{sub 60} are ω{sub Q} = 8.21(36) Mrad s{sup -1} and η = 0.41(9), respectively. The fast relaxation constant is 0.0031(4) ns{sup -1}. Similarly, mercury atoms also exhibit a single static and a fast component. The static site has a quadrupole frequency ω{sub Q} = 283.0(12.4) Mrad s{sup -1} and η = 0 with a fraction of 30 %. The fast relaxation constant is 0.045(8) ns{sup -1} with a fraction of 70 %, very similar to that of cadmium.

RECOVERY OF MERCURY FROM CONTAMINATED PRIMARY AND SECONDARY WASTES

International Nuclear Information System (INIS)

A. Faucette; J. Bognar; T. Broderick; T. Battaglia

2000-01-01

Effective removal of mercury contamination from water is a complex and difficult problem. In particular, mercury treatment of natural waters is difficult because of the low regulatory standards. For example, the Environmental Protection Agency has established a national ambient water quality standard of 12 parts-per-trillion (ppt), whereas the standard is 1.8 ppt in the Great Lakes Region. In addition, mercury is typically present in several different forms, but sorption processes are rarely effective with more than one or two of these forms. To meet the low regulatory discharge limits, a sorption process must be able to address all forms of mercury present in the water. One approach is to apply different sorbents in series depending on the mercury speciation and the regulatory discharge limits. Four new sorbents have been developed to address the variety of mercury species present in industrial discharges and natural waters. Three of these sorbents have been field tested on contaminated creek water at the Y-12 Plant. Two of these sorbents have demonstrated very high removal efficiencies for soluble mercury species, with mercury concentrations at the outlet of a pilot-scale system less than 12 ppt for as long as six months. The other sorbent tested at the Y-12 Plant is targeted at colloidal mercury that is not removed by standard sorption or filtration processes. At the Y-12 Plant, colloidal mercury appears to be associated with iron, so a sorbent that removes mercury-iron complexes in the presence of a magnetic field was evaluated. Field results indicate good removal of this mercury fraction from the Y-12 waters. In addition, this sorbent is easily regenerated by simply removing the magnetic field and flushing the columns with water. The fourth sorbent is still undergoing laboratory development, but results to date indicate exceptionally high mercury sorption capacity. The sorbent is capable of removing all forms of mercury typically present in natural and

Vaporization of elemental mercury from pools of molten lead at low concentrations

International Nuclear Information System (INIS)

Greene, G.A.; Finfrock, C.C.

2000-01-01

Should coolant accidentally be lost to the APT (Accelerator Production of Tritium) blanket and target, and the decay heat in the target be deposited in the surrounding blanket by thermal radiation, temperatures in the blanket modules could exceed structural limits and cause a physical collapse of the blanket modules into a non-coolable geometry. Such a sequence of unmitigated events could result in some melting of the APT blanket and create the potential for the release of mercury into the target-blanket cavity air space. Experiments were conducted which simulate such hypothetical accident conditions in order to measure the rate of vaporization of elemental mercury from pools of molten lead to quantify the possible severe accident source term for the APT blanket region. Molten pools of from 0.01% to 0.10% mercury in lead were prepared under inert conditions. Experiments were conducted, which varied in duration from several hours to as long as a month, to measure the mercury vaporization from the lead pools. The melt pools and gas atmospheres were held fixed at 340 C during the tests. Parameters which were varied in the tests included the mercury concentration, gas flow rate over the melt and agitation of the melt, gas atmosphere composition and the addition of aluminum to the melt. The vaporization of mercury was found to scale roughly linearly with the concentration of mercury in the pool. Variations in the gas flow rates were not found to have any effect on the mass transfer, however agitation of the melt by a submerged stirrer did enhance the mercury vaporization rate. The rate of mercury vaporization with an argon (inert) atmosphere was found to exceed that for an air (oxidizing) atmosphere by as much as a factor of from ten to 20; the causal factor in this variation was the formation of an oxide layer over the melt pool with the air atmosphere which served to retard mass transfer across the melt-atmosphere interface. Aluminum was introduced into the melt to

26 CFR 1.199-6 - Agricultural and horticultural cooperatives.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Agricultural and horticultural cooperatives. 1....199-6 Agricultural and horticultural cooperatives. (a) In general. A patron who receives a qualified... cooperative (cooperative) (as defined in paragraph (f) of this section) is allowed a deduction under § 1.199-1...

Selenium's importance in regulatory issues regarding mercury

Energy Technology Data Exchange (ETDEWEB)

Raymond, Laura J.; Ralston, Nicholas V.C. [University of North Dakota Energy and Environmental Research Center, 15 North 23rd Street, Stop 9018, Grand Forks, ND 58202-9018 (United States)

2009-11-15

Current seafood safety and health risk assessment criteria use mercury concentrations as their sole basis. This unfortunate limitation omits consideration of selenium, an essential trace element that appears to be the primary molecular target of mercury toxicity. Although selenium has been recognized for decades as a means of counteracting mercury toxicity, its effects have often been overlooked or misunderstood. Experimental animal studies have demonstrated that increasing concentrations of selenium throughout the normal dietary range increasingly counteracts methylmercury toxicity. Dietary concentrations of selenium that are slightly less than the average amount present in ocean fish have been shown to completely prevent the onset of toxic symptoms of mercury toxicity, while animals fed lesser amounts of selenium rapidly sickened and died. Dietary selenium from a variety of sources including ocean fish such as tuna, swordfish, menhaden, and rockfish has been shown to counteract mercury toxicity. Since ocean fish are among the richest sources of dietary selenium, it is important to include selenium concentration measurements in future mercury risk assessments and seafood safety criteria. Mercury:selenium molar ratios in blood provide far more consistent and physiologically meaningful risk assessments. Comprehensive seafood safety criteria such as the Selenium Health Benefit Value enable clear differentiation between seafoods that are safe and those that are hazardous for human consumption. Use of parameters that integrate mercury-selenium relationships also make it easy to understand the differences between the findings of maternal mercury exposure studies that have been performed in New Zealand, the Faroes, the Seychelles, and the United Kingdom. Development of criteria for evaluating mercury-selenium interactions will enhance environmental protection and improve public safety. (author)

Mercury and Your Health

Science.gov (United States)

... the Risk of Exposure to Mercury Learn About Mercury What is Mercury What is Metallic mercury? Toxicological Profile ToxFAQs Mercury Resources CDC’s National Biomonitoring Program Factsheet on Mercury ...

Tracing mercury pathways in Augusta Bay (southern Italy) by total concentration and isotope determination

International Nuclear Information System (INIS)

Bonsignore, M.; Tamburrino, S.; Oliveri, E.; Marchetti, A.; Durante, C.; Berni, A.; Quinci, E.; Sprovieri, M.

2015-01-01

The mercury (Hg) pollution of sediments is the main carrier of Hg for the biota and, subsequently, for the local fish consumers in Augusta Bay area (SE Sicily, Italy), a coastal marine system affected by relevant sewage from an important chlor-alkali factory. This relationship was revealed by the determination of Mass Dependent (MDF) and Mass Independent Fractionation (MIF) of Hg isotopes in sediment, fish and human hair samples. Sediments showed MDF but no MIF, while fish showed MIF, possibly due to photochemical reduction in the water column and depending on the feeding habitat of the species. Benthic and demersal fish exhibited MDF similar to that of sediments in which anthropogenic Hg was deposited, while pelagic organisms evidenced higher MDF and MIF due to photoreduction. Human hair showed high values of δ 202 Hg (offset of +2.2‰ with respect to the consumed fish) and Δ 199 Hg, both associated to fish consumption. - Highlights: • We report the Hg isotope ratios of sediments, fish and human hair in Augusta Bay. • Hg isotopes show mercury transfers from sediments to benthic and demersal fish. • MIF in fish appears to be driven by effect of photoreduction. • MIF in human hair is inherited by fish consumption. - The mercury (Hg) isotope composition of sediments, fish muscles and human hair has been investigated from the highly polluted Augusta Bay (SE Sicily, Italy)

Safety concept for spallation target system. JAERI/KEK joint project

International Nuclear Information System (INIS)

Kobayashi, K.; Kaminaga, M.; Haga, K.; Kinoshita, H.; Hino, R.

2001-01-01

A MW-class mercury target of the spallation target generates much larger amounts of radioactive nuclides than existing spallation neutron sources. To estimate the maximum level of public exposure under the guillotine break of mercury pipelines that is one of the major accidents of the target system, the hazard analyses were carried out by using a transportation model which considers heat transmission of mercury decay heat, diffusion of evaporated radioactive nuclides, etc. In the analyses, mercury, iodine, bromine and noble gas were selected as the effective source term because of their high vapor pressures and activation levels. From the preliminary analytical results obtained under the conservative conditions of 2 m/s of the air velocity around the mercury leakage area, the maximum level of the public exposure was approximately 5.8 x 10 -3 mSv. This level is negligible in comparison with 1 mSV one-year natural radiation exposure. (author)

Mercury Quick Facts: Health Effects of Mercury Exposure

Science.gov (United States)

... 2012 What are the Health Effects of Mercury Exposure? The health effects that can be caused by breathing mercury depend ... they breathe faster and have smaller lungs. Health effects caused by long-term exposure to mercury vapors • • Anxiety • • Excessive shyness • • Anorexia • • Sleeping ...

Mercury balance analysis

International Nuclear Information System (INIS)

Maag, J.; Lassen, C.; Hansen, E.

1996-01-01

A detailed assessment of the consumption of mercury, divided into use areas, was carried out. Disposal and emissions to the environment were also qualified. The assessment is mainly based on data from 1992 - 1993. The most important source of emission of mercury to air is solid waste incineration which is assessed in particular to be due to the supply of mercury in batteries (most likely mercury oxide batteries from photo equipment) and to dental fillings. The second most important source of mercury emission to air is coal-fired power plants which are estimated to account for 200-500 kg of mercury emission p.a. Other mercury emissions are mainly related to waste treatment and disposal. The consumption of mercury is generally decreasing. During the period from 1982/83 - 1992-93, the total consumption of mercury in Denmark was about halved. This development is related to the fact that consumption with regard to several important use areas (batteries, dental fillings, thermometers etc.) has been significantly reduced, while for other purposes the use of mercury has completely, or almost disappeared, i.e. (fungicides for seed, tubes etc.). (EG)

Mercury Phase II Study - Mercury Behavior in Salt Processing Flowsheet

International Nuclear Information System (INIS)

Jain, V.; Shah, H.; Wilmarth, W. R.

2016-01-01

Mercury (Hg) in the Savannah River Site Liquid Waste System (LWS) originated from decades of canyon processing where it was used as a catalyst for dissolving the aluminum cladding of reactor fuel. Approximately 60 metric tons of mercury is currently present throughout the LWS. Mercury has long been a consideration in the LWS, from both hazard and processing perspectives. In February 2015, a Mercury Program Team was established at the request of the Department of Energy to develop a comprehensive action plan for long-term management and removal of mercury. Evaluation was focused in two Phases. Phase I activities assessed the Liquid Waste inventory and chemical processing behavior using a system-by-system review methodology, and determined the speciation of the different mercury forms (Hg+, Hg++, elemental Hg, organomercury, and soluble versus insoluble mercury) within the LWS. Phase II activities are building on the Phase I activities, and results of the LWS flowsheet evaluations will be summarized in three reports: Mercury Behavior in the Salt Processing Flowsheet (i.e. this report); Mercury Behavior in the Defense Waste Processing Facility (DWPF) Flowsheet; and Mercury behavior in the Tank Farm Flowsheet (Evaporator Operations). The evaluation of the mercury behavior in the salt processing flowsheet indicates, inter alia, the following: (1) In the assembled Salt Batches 7, 8 and 9 in Tank 21, the total mercury is mostly soluble with methylmercury (MHg) contributing over 50% of the total mercury. Based on the analyses of samples from 2H Evaporator feed and drop tanks (Tanks 38/43), the source of MHg in Salt Batches 7, 8 and 9 can be attributed to the 2H evaporator concentrate used in assembling the salt batches. The 2H Evaporator is used to evaporate DWPF recycle water. (2) Comparison of data between Tank 21/49, Salt Solution Feed Tank (SSFT), Decontaminated Salt Solution Hold Tank (DSSHT), and Tank 50 samples suggests that the total mercury as well as speciated

EURISOL-DS MULTI-MW TARGET ISSUES: BEAM WINDOW AND TRANSVERSE FILM TARGET

CERN Document Server

Adonai Herrera-Martínez, Yacine Kadi

The analysis of the EURISOL-DS Multi_MW target precise geometry (Fig.1) has proved that large fission yields can be achieved with a 4 MW, providing a technically feasible design to evacuate the power deposited in the liquid mercury. Different designs for the mercury flow have been proposed, which maintain its temperature below the boiling point with moderate flow speeds (maximum 4 m/s).

Dynamic Pressure of Liquid Mercury Target During 800-MeV Proton Thermal Shock Tests

International Nuclear Information System (INIS)

Allison, S.W.; Andriulli, J.B.; Cates, M.R.; Earl, D.D.; Haines, J.R.; Morrissey, F.X.; Tsai, C.C.; Wender, S.

2000-01-01

Described here are efforts to diagnose transient pressures generated by a short-pulse (about 0.5 microseconds) high intensity proton (∼ 2 * 10 14 per pulse) beam. Proton energy is 800-MeV. The tests were performed at the Los Alamos Neutron Science Center - Weapons Neutron Research (LANSCE-WNR). Such capability is required for understanding target interaction for the Spallation Neutron Source project as described previously at this conference.1-4 The main approach to effect the pressure measurements utilized the deflection of a diaphragm in intimate contact with the mercury. There are a wide variety of diaphragm-deflection methods used in scientific and industrial applications. Many deflection-sensing approaches are typically used, including, for instance, capacitive and optical fiber techniques. It was found, however, that conventional pressure measurement using commercial pressure gages with electrical leads was not possible due to the intense nuclear radiation environment. Earlier work with a fiber optic strain gauge demonstrated the viability of using fiber optics for this environment

32 CFR 199.20 - Continued Health Care Benefit Program (CHCBP).

Science.gov (United States)

2010-07-01

... Privilege Card”; (iii) A front and back copy of a DD Form 1173, “Uniformed Services Identification and...). 199.20 Section 199.20 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS CIVILIAN HEALTH AND MEDICAL PROGRAM OF THE UNIFORMED SERVICES (CHAMPUS...

46 CFR 199.40 - Evaluation, testing and approval of lifesaving appliances and arrangements.

Science.gov (United States)

2010-10-01

... appliances and arrangements. 199.40 Section 199.40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LIFESAVING APPLIANCES AND ARRANGEMENTS LIFESAVING SYSTEMS FOR CERTAIN INSPECTED VESSELS General § 199.40 Evaluation, testing and approval of lifesaving appliances and arrangements. (a) Each item of...

Selective modification of NMR relaxation time in human colorectal carcinoma by using gadolinium-diethylenetriaminepentaacetic acid conjugated with monoclonal antibody 19-9.

Science.gov (United States)

Curtet, C; Tellier, C; Bohy, J; Conti, M L; Saccavini, J C; Thedrez, P; Douillard, J Y; Chatal, J F; Koprowski, H

1986-01-01

Monoclonal antibody 19-9 (mAb 19-9) against human colon adenocarcinoma was conjugated with gadolinium X diethylenetriaminepentaacetic acid (Gd X DTPA) and used as a contrast agent in nuclear magnetic resonance (NMR) in an effort to improve tumor target selectivity in nude mice. The data indicate that Gd X DTPA-mAb 19-9 in solution decreased the T1 relaxation of water protons at 90 MHz in direct proportion to the gadolinium concentration, and this effect was greater than in Gd X DTPA solutions. T1 relaxation time at 90 MHz, measured in tumors removed from nude mice 24 hr after injection of Gd X DTPA-mAb 19-9 (Gd, 20 mumol/kg; 16 DTPA molecules per mAb molecule), was significantly decreased (by 15%) as compared with the control group. Similar results were obtained in tumors from mice injected with Gd X DTPA-mAb 19-9 solutions in which Gd was used at 2, 6, or 10 mumol/kg (16 DTPA molecules per mAb molecule). These doses are lower than those commonly used for Gd X DTPA (10-100 mumol/kg) as contrast agent. Tumor localization by the Gd X DTPA-mAb 19-9 complex containing radioactive Gd (0.3 microCi/microgram of 153Gd) to confirm scintigraphy revealed significant concentrations of the complex (5% of the injected dose per gram of tissue) in the tumor. Scan images recorded in planar scintigraphy at day 5 showed good visualization of tumors. Images PMID:3459174

Distribution and retention of organic and inorganic mercury in methyl mercury-treated neonatal rats

International Nuclear Information System (INIS)

Thomas, D.J.; Fisher, H.L.; Sumler, M.R.; Hall, L.L.; Mushak, P.

1988-01-01

Seven-day-old Long Evans rats received one mumol of 203 Hg-labeled methyl mercury/kg sc and whole body retention and tissue distribution of organic and inorganic mercury were examined for 32 days postdosing. Neonates cleared mercury slowly until 10 days postdosing when the clearance rate abruptly increased. During the interval when whole body clearance of mercury was extremely slow, methyl mercury was metabolized to inorganic mercury. Peak concentration of mercury in kidney occurred at 2 days postdosing. At 32 days postdosing, 8% of mercury in kidney was in an organic from. Liver mercury concentration peaked at 2 days postdosing and organic mercury accounted for 38% at 32 days postdosing. Brain concentrations of mercury peaked at 2 days postdosing. At 10 days postdosing, organic mercury accounted for 86% of the brain mercury burden, and, at 32 days postdosing, for 60%. The percentage of mercury body burden in pelt rose from 30 to 70% between 1 and 10 days postdosing. At 32 days postdosing pelt contained 85% of the body burden of mercury. At all time points, about 95% of mercury in pelt was in an organic form. Compartmental analysis of these data permitted development of a model to describe the distribution and excretion of organic and inorganic mercury in methyl mercury-treated neonatal rats

46 CFR 199.214 - Immersion suits and thermal protective aids.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Immersion suits and thermal protective aids. 199.214... Passenger Vessels § 199.214 Immersion suits and thermal protective aids. (a) Each passenger vessel must... an immersion suit. (c) The immersion suits and thermal protective aids required under paragraphs (a...

46 CFR 199.110 - Survival craft muster and embarkation arrangements.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft muster and embarkation arrangements. 199... § 199.110 Survival craft muster and embarkation arrangements. (a) Each muster station must have... emergency source of electrical power. (e) Each davit-launched and free-fall survival craft muster station...

Elevated serum CA 19-9 at screening tests: underlying conditions and role of abdominopelvic CT

Energy Technology Data Exchange (ETDEWEB)

Kim, Ji Yang [University of Louisville, Department of Radiology and Molecular Imaging Research Center, Louisville, KY (United States); Seoul National University Hospital, Department of Radiology, Healthcare System Gangnam Center, Seoul (Korea, Republic of); Kim, Se Hyung [Seoul National University Hospital, Department of Radiology and the Institute of Radiation Medicine, Seoul (Korea, Republic of); Kim, Soo Young [Seoul National University Hospital, Department of Radiology, Healthcare System Gangnam Center, Seoul (Korea, Republic of); Bundang CHA Hospital, Department of Radiology, Bundang (Korea, Republic of)

2014-10-15

To investigate underlying conditions of patients with elevated CA 19-9 at screening tests and to evaluate diagnostic performance of abdominopelvic CT. One hundred and thirteen patients with elevated CA 19-9 (>37 U/ml) who underwent abdominopelvic CT in a screening program were selected. Underlying conditions were determined by reviewing all available data and follow-up records. Patients were categorized into malignancy, benign, and normal/non-related disease groups. Their mean CA 19-9 and percent of patients with CA 19-9 ≥ 100 U/ml were compared. Diagnostic sensitivity of CT for detecting underlying conditions of elevated CA 19-9 was analysed. Seventeen patients (17/113, 15 %) had 17 elevated CA 19-9-related malignancies, and 55 patients (55/113, 48.7 %) had 70 benign diseases. Mean CA 19-9 and percent of patients with CA 19-9 ≥ 100 U/ml in the malignancy group were significantly higher than in the two other groups. CT detected all except one malignant lesion with a detection sensitivity of 94.1 % (16/17). Of 70 CA 19-9-related benign diseases, CT detected 34 benign diseases (48.6 %) providing an alternative diagnosis for elevated CA 19-9. Abdominopelvic CT is not only useful in detecting malignancies, but can also diagnose alternative benign causes of elevated CA 19-9 in asymptomatic screening tests. (orig.)

32 CFR 199.2 - Definitions.

Science.gov (United States)

2010-07-01

... CIVILIAN HEALTH AND MEDICAL PROGRAM OF THE UNIFORMED SERVICES (CHAMPUS) § 199.2 Definitions. (a) General... terminology is “treatment through prayer and spiritual means,” which is employed by an authorized Christian... rendered, regardless of the terminology used. Abuse. For the purposes of this part, abuse is defined as any...

Preliminary study of mercury target structure

Energy Technology Data Exchange (ETDEWEB)

Kaminaga, Masanori; Haga, Katsuhiro; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kumasaka, Katsuyuki; Uchida, Shoji; Nakagawa, Toshi; Mori, Seiji; Nishikawa, Akira

1997-11-01

Development of a proton accelerator based neutron source (1.5 GeV, 5.3 mA (for neutron source 3.3 mA), thermal power 8 MW) is currently conducted by the Special Task Force for Neutron Science Initiative, JAERI. Preliminary design studies and related R and D of a solid metal target for the first stage (1.5 GeV, 1 mA) and a liquid metal target for both the first and second stages (1.5 GeV, 3.3 mA) are conducted by the Target Group to develop both solid and liquid metal target systems. A few kinds of target structures have been investigated in FY 1996 and the preliminary results for the target structures are described in this paper. Investigation results of alternative materials for the target container are also described in this paper. (author)

Comparison of damage induced by mercury chloride and ionizing radiation in the susceptible rat model

International Nuclear Information System (INIS)

Kim, Ji Hyang; Yoon, Yong Dal; Kim, Jin Kyu

2003-01-01

Mercury (Hg), one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. Although the reports indicate that mercury induces a deleterious damage, little has been reported from the investigations of mercury effects in living things. The purpose of this study is to evaluate the effects of mercury chloride and ionizing radiation. Prepubertal male F-344 rats were administered mercury chloride in drinking water throughout the experimental period. Two weeks after whole body irradiation, organs were collected for measuring the induced injury. Serum levels of GOT, GPT, ALP, and LDH were checked in the experimental groups and the hematological analysis was accomplished in plasma. In conclusion, the target organ of mercury chloride seems to be urinary organs and the pattern of damage induced by mercury differs from that of the irradiated group

Method for removal and stabilization of mercury in mercury-containing gas streams

Science.gov (United States)

Broderick, Thomas E.

2005-09-13

The present invention is directed to a process and apparatus for removing and stabilizing mercury from mercury-containing gas streams. A gas stream containing vapor phase elemental and/or speciated mercury is contacted with reagent, such as an oxygen-containing oxidant, in a liquid environment to form a mercury-containing precipitate. The mercury-containing precipitate is kept or placed in solution and reacts with one or more additional reagents to form a solid, stable mercury-containing compound.

CA 19-9 as a marker in addition to CEA to monitor colorectal cancer.

Science.gov (United States)

Stiksma, Jolanda; Grootendorst, Diana C; van der Linden, Peter Willem G

2014-12-01

Carcinoembryonic antigen is the commonly used tumor marker in patients with colorectal cancer, and CA 19-9 might be an additional marker. The aim of this retrospective study was to investigate whether CA 19-9 levels can be used to monitor the disease process in patients with colorectal cancer who had no elevated CEA levels. The secondary aim was to determine if preoperative increased levels of CEA and CA 19-9 were associated with mortality. Two sets of data from patients with histologically confirmed colorectal cancer, were included in a single-center study. First, patients with a minimum of 3 serial measurements of CA 19-9 and CEA tumor markers were related to the clinical course of their disease. Second, patients with preoperative levels of CEA and CA 19-9 were related to survival. In patients with colorectal cancer and 3 serial measurements of tumor markers, 7.3% had only increased CA 19-9 levels without increased CEA levels, and 55.4% of the patients had an increase of CA 19-9 and CEA levels. In the patients with available preoperative markers, patients with only an increase of CA 19-9 had a significantly decreased 5-year survival compared with patients with an increase of only CEA (P = .013). CA 19-9 can be used as additional marker to follow the disease process in patients with colorectal cancer without an increase in CEA level. Patients with preoperative increased CA 19-9 level had a poorer 5-year survival than patients with preoperative increased CEA levels. Copyright © 2014 Elsevier Inc. All rights reserved.

46 CFR 199.10 - Applicability.

Science.gov (United States)

2010-10-01

... located. Other regulations may also apply. 3 Not including vessels solely navigating the Great Lakes of... (4) Vessels solely navigating the Great Lakes of North America and the River Saint Lawrence as far... number and type of survival craft specified in table 199.630 of this part and cargo vessels in oceans and...

Mercury-impacted scrap metal: Source and nature of the mercury.

Science.gov (United States)

Finster, Molly E; Raymond, Michelle R; Scofield, Marcienne A; Smith, Karen P

2015-09-15

The reuse and recycling of industrial solid wastes such as scrap metal is supported and encouraged both internationally and domestically, especially when such wastes can be used as substitutes for raw material. However, scrap metal processing facilities, such as mini-mills, have been identified as a source of mercury (Hg) emissions in the United States. This research aims to better define some of the key issues related to the source and nature of mercury in the scrap metal waste stream. Overall, it is difficult to pinpoint the key mercury sources feeding into scrap metal recycling facilities, quantify their associated mercury concentrations, or determine which chemical forms are most significant. Potential sources of mercury in scrap metal include mercury switches from discarded vehicles, electronic-based scrap from household appliances and related industrial systems, and Hg-impacted scrap metal from the oil and gas industry. The form of mercury associated with scrap metal varies and depends on the source type. The specific amount of mercury that can be adsorbed and retained by steel appears to be a function of both metallurgical and environmental factors. In general, the longer the steel is in contact with a fluid or condensate that contains measurable concentrations of elemental mercury, the greater the potential for mercury accumulation in that steel. Most mercury compounds are thermally unstable at elevated temperatures (i.e., above 350 °C). As such, the mercury associated with impacted scrap is expected to be volatilized out of the metal when it is heated during processing (e.g., shredding or torch cutting) or melted in a furnace. This release of fugitive gas (Hg vapor) and particulates, as well as Hg-impacted bag-house dust and control filters, could potentially pose an occupational exposure risk to workers at a scrap metal processing facility. Thus, identifying and characterizing the key sources of Hg-impacted scrap, and understanding the nature and extent

32 CFR 199.5 - TRICARE Extended Care Health Option (ECHO).

Science.gov (United States)

2010-07-01

... medicines. Drugs and medicines that do not meet the requirements of § 199.4 or § 199.21 are excluded. (17..., as determined by the Director, TRICARE Management Activity or designee. (B) Alternative allocation... following the death of a beneficiary or as of the effective date of a beneficiary's loss of ECHO eligibility...

Mercury contamination extraction

Science.gov (United States)

Fuhrmann, Mark [Silver Spring, MD; Heiser, John [Bayport, NY; Kalb, Paul [Wading River, NY

2009-09-15

Mercury is removed from contaminated waste by firstly applying a sulfur reagent to the waste. Mercury in the waste is then permitted to migrate to the reagent and is stabilized in a mercury sulfide compound. The stable compound may then be removed from the waste which itself remains in situ following mercury removal therefrom.

Global Trends in Mercury Management

Science.gov (United States)

Choi, Kyunghee

2012-01-01

The United Nations Environmental Program Governing Council has regulated mercury as a global pollutant since 2001 and has been preparing the mercury convention, which will have a strongly binding force through Global Mercury Assessment, Global Mercury Partnership Activities, and establishment of the Open-Ended Working Group on Mercury. The European Union maintains an inclusive strategy on risks and contamination of mercury, and has executed the Mercury Export Ban Act since December in 2010. The US Environmental Protection Agency established the Mercury Action Plan (1998) and the Mercury Roadmap (2006) and has proposed systematic mercury management methods to reduce the health risks posed by mercury exposure. Japan, which experienced Minamata disease, aims vigorously at perfection in mercury management in several ways. In Korea, the Ministry of Environment established the Comprehensive Plan and Countermeasures for Mercury Management to prepare for the mercury convention and to reduce risks of mercury to protect public health. PMID:23230466

Interfering Effect of Black Tea Consumption on Diagnosis of Pancreatic Cancer by CA 19-9.

Science.gov (United States)

Al-Janabi, Ali Abdul Hussein S; Tawfeeq, Ekhlas F

2017-06-01

The study aims to determine the possible effects of black tea consumption on the level of CA 19-9 antigen in the human body. The level of CA 19-9 was measured in 270 healthy individuals who consumed heavy amounts of black tea. About 43.3 % of involved individuals were revealed to have elevated levels of CA 19-9. Males with high values of CA 19-9 represented the greatest number of involved individuals. The cutoff value of high levels of CA 19-9 in all individuals was ranged 69-105 U/ml. Consuming heavy amounts of black tea could be considered an important interfering factor that affects the levels of CA 19-9. The cutoff or predictive value of CA 19-9 in heavy-consuming people of black tea was determined.

SNS Target Test Facility for remote handling design and verification

International Nuclear Information System (INIS)

Spampinato, P.T.; Graves, V.B.; Schrock, S.L.

1998-01-01

The Target Test Facility will be a full-scale prototype of the Spallation Neutron Source Target Station. It will be used to demonstrate remote handling operations on various components of the mercury flow loop and for thermal/hydraulic testing. This paper describes the remote handling aspects of the Target Test Facility. Since the facility will contain approximately 1 cubic meter of mercury for the thermal/hydraulic tests, an enclosure will also be constructed that matches the actual Target Test Cell

Mercurial poisoning

Energy Technology Data Exchange (ETDEWEB)

Gorton, B

1924-01-01

Cats which had been kept in a thermometer factory to catch rats were afflicted with mercury poisoning. So were the rats they were supposed to eat. The symptoms of mercury poisoning were the same in both species. The source of mercury for these animals is a fine film of the metal which coats floors, a result of accidental spills during the manufacturing process.

Mercury emissions from South Africa’s coal-fired power stations

Directory of Open Access Journals (Sweden)

Belinda L. Garnham

2016-12-01

can be achieved as a co-benefit of installing other emission abatement technologies. At the very least, more accurate calculations of mercury emissions per power station should be obtained by measuring the mercury content of more recent coal samples, and developing power station-specific ERF’s before mercury emission regulations are established or an investment into targeted mercury emission reduction technology is made.

9 CFR 381.199 - Inspection of poultry products offered for entry.

Science.gov (United States)

2010-01-01

... AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Imported Poultry... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Inspection of poultry products offered for entry. 381.199 Section 381.199 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...

Association between serum CA 19-9 and metabolic syndrome: A cross-sectional study.

Science.gov (United States)

Du, Rui; Cheng, Di; Lin, Lin; Sun, Jichao; Peng, Kui; Xu, Yu; Xu, Min; Chen, Yuhong; Bi, Yufang; Wang, Weiqing; Lu, Jieli; Ning, Guang

2017-11-01

Increasing evidence suggests that serum CA 19-9 is associated with abnormal glucose metabolism. However, data on the association between CA 19-9 and metabolic syndrome is limited. The aim of the present study was to investigate the association between serum CA 19-9 and metabolic syndrome. A cross-sectional study was conducted on 3641 participants aged ≥40 years from the Songnan Community, Baoshan District in Shanghai, China. Logistic regression analysis was used to evaluate the association between serum CA 19-9 and metabolic syndrome. Multivariate logistic regression analysis showed that compared with participants in the first tertile of serum CA 19-9, those in the second and third tertiles had increased odds ratios (OR) for prevalent metabolic syndrome (multivariate adjusted OR 1.46 [95% confidence interval {CI} 1.11-1.92] and 1.51 [95% CI 1.14-1.98]; P trend  = 0.005). In addition, participants with elevated serum CA 19-9 (≥37 U/mL) had an increased risk of prevalent metabolic syndrome compared with those with serum CA 19-9 metabolic syndrome. In order to confirm this association and identify potential mechanisms, prospective cohort and mechanic studies should be performed. © 2017 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Evaluation of Energy Consumption in the Mercury Treatment of Phosphor Powder from Spent Fluorescent Lamps Using a Thermal Process

Directory of Open Access Journals (Sweden)

Yong Choi

2017-11-01

Full Text Available In a pilot-plant-scale thermal mercury treatment of phosphor powder from spent fluorescent lamps, energy consumption was estimated to control mercury content by the consideration of reaction kinetics. Mercury content was analyzed as a function of treatment temperature and time. The initial mercury content of the phosphor powder used in the thermal process was approximately 3500 mg/kg. The target mercury content in the phosphor powder thermal process of the phosphor powder was 5 mg/kg or less at 400 °C or higher because the target mercury content was recommended by Minamata Convention and Basel Convention. During thermal processing, the reaction rate was represented by a first order reaction with the Arrhenius equation. The reaction rate constant increased with temperature from 0.0112 min−1 at 350 °C to 0.0558 min−1 at 600 °C. The frequency factor was 2.51 min−1, and the activation energy was 6509.11 kcal/kg. Reaction rate constants were used to evaluate the treatment time required to reduce mercury content in phosphor powder to be less than 5 mg/kg. The total energy consumption in a pilot-plant-scale thermal process was evaluated to determine the optimal temperature for removing mercury in phosphor powder.

Toward A Neutral Mercury Optical Lattice Clock: Determination of the Magic Wavelength for the Ultraviolet clock Transition

International Nuclear Information System (INIS)

Mejri, Sinda

2012-01-01

A lattice clock combines the advantages of ion and neutral atom based clocks, namely the recoil and first order Doppler free spectroscopy allowed by the Lamb-Dicke regime. This lattice light field shifts the energy levels of the clock transition. However a wavelength can be found where the light-shift of the clock states cancelled to first order. In this thesis, we present the latest advances in optical lattice clock with mercury atoms developed at LNE-SYRTE. After a review of the current performances of different optical clock are currently under development, we focus on the concept of optical lattice clock and the features of the mercury that make him an excellent candidate for the realization of an optical lattice clock achievement the uncertainty of the level of 10 -17 . The second part is devoted to the characterization of the mercury MOT, using a sensitive detection system, which allowed us to evaluate the temperature of different isotopes present in the MOT and have a good evidence of sub-Doppler cooling for the fermionic isotopes. The third part of this these, present the experimental aspects of the implementation and the development of the laser source required for trapping mercury atoms operating near the predicted magic wavelength. Finally, we report on the Lamb-Dicke spectroscopy of the 1S0 →3 P0 clock transition in the 199 Hg atoms confined in lattice trap. With use of the ultra-stable laser system, linked to LNE-SYRTE primary frequency reference, we have determined the center frequency of the transition for a range of lattice wavelengths and different lattice depths. Analyzing these measurement, we have carried out the first experimental determination of the magic wavelength, which is the crucial step towards achieving a highly accurate frequency standard using mercury. (author)

Atmospheric mercury in Changbai Mountain area, northeastern China II. The distribution of reactive gaseous mercury and particulate mercury and mercury deposition fluxes.

Science.gov (United States)

Wan, Qi; Feng, Xinbin; Lu, Julia; Zheng, Wei; Song, Xinjie; Li, Ping; Han, Shijie; Xu, Hao

2009-08-01

Reactive gaseous mercury (RGM) and particulate mercury (Hgp) concentrations in ambient air from a remote site at Changbai Mountain area in northeastern China were intermittently monitored from August 2005 to July 2006 totaling 93 days representing fall, winter-spring and summer season, respectively. Rainwater and snow samples were collected during a whole year, and total mercury (THg) in rain samples were used to calculate wet depositional flux. A throughfall method and a model method were used to estimate dry depositional flux. Results showed mean concentrations of RGM and Hgp are 65 and 77 pg m(-3). Compared to background concentrations of atmospheric mercury species in Northern Hemisphere, RGM and Hgp are significantly elevated in Changbai area. Large values for standard deviation indicated fast reactivity and a low residence time for these mercury species. Seasonal variability is also important, with lower mercury levels in summer compared to other seasons, which is attributed to scavenging by rainfall and low local mercury emissions in summer. THg concentrations ranged from 11.5 to 15.9 ng L(-1) in rainwater samples and 14.9-18.6 ng L(-1) in throughfall samples. Wet depositional flux in Changbai area is calculated to be 8.4 microg m(-2) a(-1), and dry deposition flux is estimated to be 16.5 microg m(-2) a(-1) according to a throughfall method and 20.2 microg m(-2) a(-1) using a model method.

Binary mixtures of mercury/ selenium, and lead/selenium

African Journals Online (AJOL)

Physiologically-based biokinetic models have been developed for predicting simultaneously the Absorption, Distribution, Metabolism and Elimination (ADME) properties of lead (Pb) and selenium (Se), and mercury (Hg) and selenium in a number of target tissues of humans. This was done for three population groups, ...

Mercury accumulation plant Cyrtomium macrophyllum and its potential for phytoremediation of mercury polluted sites.

Science.gov (United States)

Xun, Yu; Feng, Liu; Li, Youdan; Dong, Haochen

2017-12-01

Cyrtomium macrophyllum naturally grown in 225.73 mg kg -1 of soil mercury in mining area was found to be a potential mercury accumulator plant with the translocation factor of 2.62 and the high mercury concentration of 36.44 mg kg -1 accumulated in its aerial parts. Pot experiments indicated that Cyrtomium macrophyllum could even grow in 500 mg kg -1 of soil mercury with observed inhibition on growth but no obvious toxic effects, and showed excellent mercury accumulation and translocation abilities with both translocation and bioconcentration factors greater than 1 when exposed to 200 mg kg -1 and lower soil mercury, indicating that it could be considered as a great mercury accumulating species. Furthermore, the leaf tissue of Cyrtomium macrophyllum showed high resistance to mercury stress because of both the increased superoxide dismutase activity and the accumulation of glutathione and proline induced by mercury stress, which favorited mercury translocation from the roots to the aerial parts, revealing the possible reason for Cyrtomium macrophyllum to tolerate high concentration of soil mercury. In sum, due to its excellent mercury accumulation and translocation abilities as well as its high resistance to mercury stress, the use of Cyrtomium macrophyllum should be a promising approach to remediating mercury polluted soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ratio of tritiated water and hydrogen generated in mercury through a nuclear reaction

Energy Technology Data Exchange (ETDEWEB)

Manabe, K. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (JAEA), Tokai, Naka-gun, Ibaraki 319-1195 (Japan)], E-mail: manabe.kentaro@jaea.go.jp; Yokoyama, S. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (JAEA), Tokai, Naka-gun, Ibaraki 319-1195 (Japan)

2008-02-15

Tritium generated in a mercury target is a source of potential exposure of personnel at high-energy accelerator facilities. Knowledge of the chemical form of tritium is necessary to estimate the internal doses. We studied the tritium generation upon thermal neutron irradiation of a mercury target modified into liquid lithium amalgam to examine the ratio of tritiated water ([{sup 3}H]H{sub 2}O) and tritiated hydrogen ([{sup 3}H]H{sub 2}). The ratio between [{sup 3}H]H{sub 2}O and [{sup 3}H]H{sub 2} generated in lithium amalgam was 4:6 under these experimental conditions.

Preliminary investigations on the preparation of gold nanoparticles intrinsically radiolabeled with 199Au

International Nuclear Information System (INIS)

Vimalnath, K.V.; Chakraborty, Sudipta; Dash, Ashutosh

2016-01-01

Radiolabeled nanoparticles are of great interest in the current perspective of the nuclear medicine. Water dispersible materials with nanoscale dimensions are finding role in biomedical application owing to their size. These particles can access otherwise unreachable regions in tumor mainly due to Enhanced Permeability and Retention (EPR) effect. Nanoparticles of gold (AuNPs) can bind to a wide range of biologically active molecules with functional groups that have high affinity for the gold surface. Sulfur containing compounds (e.g. thiols, disulfides), organic phosphates, amines, PEG, etc. are some of the well known surface modifiers. Functional thiolates, oligonucleotides, peptides and PEGs are introduced upon subsequent bimolecular substitution of a ligand by a functional thiol easily attached to AuNPs. Owing to its favourable decay characteristics 199 Au (T 1/2 = 3.15 d, E âmax = 474 keV, Eg 158.4 keV (36.9 %) and 208.2 keV (8.4 %)) is an attractive radionuclide for theragnostic applications. In the present work, we have carried out preliminary radiochemical investigations on the preparation of gold nanoparticles intrinsically radiolabeled with 199 Au for its potential utility as a theragnostic agent targeted delivery to the tumors

Toward a Unified Understanding of Mercury and Methylated Mercury from the World's Oceans

Science.gov (United States)

McNutt, M. K.; Krabbenhoft, D. P.; Landing, W. M.; Sunderland, E. M.

2012-12-01

Marine fish and shellfish are the main source of toxic methylmercury exposure for humans. As recently as decade ago, very limited aqueous methylated mercury data were available from marine settings, resulting in a generally poor understanding of the processes controlling mercury in pelagic marine food webs. Recent oceanographic cruises have significantly improved availability of reliable measurements of methylated mercury and total mercury in seawater. This presentation will focus on vertical seawater profiles collected to depths 1000 m from three recent sampling efforts in collaboration with the CLIVAR Repeat Hydrography Program sponsored by NOAA including: 1) the northeastern Pacific (P16N cruise from Honolulu, Hawaii to Kodiak, Alaska); (2) the southern Indian Ocean (I5 cruise from Cape Town, South Africa, to Fremantle, Australia); and, (3) the Southern Ocean cruise (S4P from McMurdo, Antarctica, to Punta Arenas, Chile). Analytical results presented were all derived from the USGS Mercury Research Lab (http://wi.water.usgs.gov/mercury-lab). Supporting data derived from these cruises on water mass ages, nutrients, carbon and dissolved oxygen provide an opportunity to develop a stronger understanding of the biogeochemical factors controlling oceanic distributions of mercury and methylated mercury. Whole-water, median total mercury, and methylated mercury concentrations for the northern Pacific, southern Indian, and Southern Ocean were 1.10, 0.80, and 1.65 pM, , and 0.11, 0.08, and 0.32 pM, respectively. For all three oceans, vertical profiles of total mercury generally show the lowest concentrations in the surface mixed layer, and concentration maxima at the 700-1000 m depths. Surface depletion of total mercury is attributed to photo-chemical reduction and evasion of gaseous elemental mercury as well as scavenging by settling particulate matter, the main vector of transport to the subsurface ocean. Methylated mercury in all the ocean profiles reveal distinct mid

Effect of tensile stress on cavitation damage formation in mercury

Energy Technology Data Exchange (ETDEWEB)

Naoe, Takashi, E-mail: naoe.takashi@jaea.go.j [J-PARC Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Kogawa, Hiroyuki [J-PARC Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Yamaguchi, Yoshihito [Nuclear Safety Research Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Futakawa, Masatoshi [J-PARC Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)

2010-03-15

Cavitation erosion or so called pitting damage was investigated under tensile stress conditions in mercury. In MW-class liquid metal spallation targets, pitting damage is a critical issue to satisfy required power and/or lifetime of the target vessel. Cavitation occurs by negative pressure which is induced through pressure wave propagation due to proton beam injection. Pitting damage is formed by microjet and/or shock wave during cavitation bubble collapse. A mercury target vessel suffers tensile stress due to thermal stress or welding. In order to investigate the effect of tensile stress on pitting damage formation, cavitation erosion tests were performed using stress imposed specimens in mercury. An ultrasonic vibratory horn and electro-Magnetic IMpact Testing Machine (MIMTM) were used to vary the cavitation intensity. In the incubation period of pitting damage, damaged area was slightly increased with increasing imposed tensile stress. In the steady state period, a mean depth of erosion was increased by the tensile stress. Additionally, in order to quantitatively evaluate the effect of tensile stress, an indentation test with Vickers indenter was carried out to quasi-statically simulate the impact load. From the measurement of the diagonal length of the indent aspect ratio and hardness, it is recognized that the threshold of the deformation, i.e. pitting damage formation, was decreased by the tensile stress.

CA 19-9 is an index of the response to neoadjunctive chemoradiation therpay in pancreatic cancer

International Nuclear Information System (INIS)

Willett, Christopher G.; Daly, William J.; Warshaw, Andrew L.

1996-01-01

Purpose: This study examines the changes of serum levels of CA 19-9 in patients with pancreatic cancer following neoadjuvant irradiation and chemotherapy to define the potential role of this tumor marker in preoperative management of these patients. Materials and Methods: Serum CA 19-9 levels were measured in 42 patients before receiving external beam irradiation with concurrent 5-fluorouracil in preparation for laparotomy and Whipple procedure or intraoperative irradiation (IORT). The CA 19-9 levels were determined again after irradiation, and changes were correlated with findings of restaging CT scan and laparatomy. Results: Following preoperative irradiation, 10 patients (24%) experienced an increase in CA 19-9 levels whereas 29 patients (69%) showed a decrease in CA 19-9. There was no change in the CA 19-9 levels of three patients (7%) after treatment. Of the 10 patients with increased CA 19-9 levels after irradiation, 9 patients (90%) had developed distant metastases or local tumor progression as determined by restaging CT scan or at laparotomy. In contrast, only 6 of 29 patients (21%) with declining CA 19-9 levels after irradiation demonstrated metastases or local tumor progression on restaging CT scan or at laparotomy. The correlation of CA 19-9 increase or decrease with disease progression or control, respectively, was statistically significant (p=0.009). Conclusions: Serum CA 19-9 levels may rise or fall during neoadjuvant therapy. A rising CA 19-9 reliably indicates cancer progression while a falling CA 19-9 connotes disease control in the majority of patients. In developing strategies for application of neoadjuvant therapy for pancreatic cancer, monitoring of CA 19-9 appears most useful for the identification of patients who manifest progressive tumor growth and metastasis in spite of this treatment

Excretion and distribution of mercury in rats, antidotes for mercury and effects of egg production and fertility of hens after mercury administration

Energy Technology Data Exchange (ETDEWEB)

Ulfvarson, U

1973-01-01

The results of investigations of the distribution and excretion of organic and inorganic mercury compounds in albino rats and white leghorn hens conducted over a period of ten years are surveyed. The storage of mercury in eggs as well as its effects on the egg-lay-frequency and hatchability of the eggs have also been studied. All investigated mercury compounds were labelled with the radioactive mercury isotope /sup 203/Hg and the mercury level was measured with a scintillation technique. Since antidotes used in the treatment of mercury poisoning influence not only the excretion of mercury, but also its distribution in the body, the effects of nine antidotes on the metabolism of different mercury compounds were also investigated. The results of the survey are presented graphically. 6 references, 15 figures, 1 table.

JAERI/KEK target material program overview

International Nuclear Information System (INIS)

Kikuchi, Kenji; Kogawa, Hiroyuki; Sasa, Toshinobu

2001-01-01

Mercury target was designed for megawatt neutron scattering facility in JAERI/KEK spallation neutron source. The incident proton energy and current are 3 GeV and 333 μA, respectively: the total proton energy is 1 MW in short pulses at a frequency of 25 Hz. Under the guide rule the mercury target was designed: the maximum temperature of target window is 170degC and induced stresses for the type 316 stainless steel are within limits of design guide. In order to demonstrate ADS (Accelerator Driven Systems) transmutation critical and engineering facilities have been designed conceptually. In engineering facility lead-bismuth spallation target station is to be planned. Objective to build the facility is to demonstrate material irradiation. According to neutronics calculation irradiation damage of the target vessel window will be 5 dpa per year. (author)

Ultralow Level Mercury Treatment Using Chemical Reduction and Air Stripping: Scoping Report

International Nuclear Information System (INIS)

Looney, B.B.

2000-01-01

Data collected during the first stage of a Savannah River Technology Center (SRTC) Strategic Research and Development Project confirmed the efficacy of chemical reduction and air stripping/sparging as an ultralow level mercury treatment concept for waters containing Hg(II). The process consists of dosing the water with low levels of stannous chloride to convert the mercury to Hg. This form of mercury can easily be removed from the water by air stripping or sparging. Samples of Savannah River Site (SRS) groundwater containing approximately 130 ng/L of total mercury (as Hg(II)) were used for the study. In undosed samples, sparging removed 0 percent of the initial mercury. In the dosed samples, all of the removals were greater than 94 percent, except in one water type at one dose. This sample, which was saturated with dissolved oxygen, showed a 63 percent reduction in mercury following treatment at the lowest dose. Following dosing at minimally effective levels and sparging, treated water contained less than 10 ng/L total mercury. In general, the data indicate that the reduction of mercury is highly favored and that stannous chloride reagent efficiently targets the Hg(II) contaminant in the presence of competing reactions. Based on the results, the authors estimated that the costs of implementing and operating an ultralow level mercury treatment process based on chemical reduction and stripping/sparging are 10 percent to 20 percent of traditional treatment technologies

Identification of bile survivin and carbohydrate antigen 199 in distinguishing cholangiocarcinoma from benign obstructive jaundice.

Science.gov (United States)

Liu, Yanfeng; Sun, Jingxian; Zhang, Qiangbo; Jin, Bin; Zhu, Min; Zhang, Zongli

2017-01-01

To investigate whether bile survivin and carbohydrate antigen 199 (CA199) can be helpful in distinguishing cholangiocarcinoma (malignant obstructive jaundice) from benign obstructive jaundice. Receiver operating characteristic curve was used to evaluate the feasibility of bile survivin and CA199 in differentiating cholangiocarcinoma from benign obstructive jaundice. The area under the curve for survivin and CA199 in bile and serum were 0.780 (p jaundice.

Mechanisms involved in the transport of mercuric ions in target tissues

Science.gov (United States)

Bridges, Christy C.; Zalups, Rudolfs K.

2016-01-01

Mercury exists in the environment in various forms, all of which pose a risk to human health. Despite guidelines regulating the industrial release of mercury into the environment, humans continue to be exposed regularly to various forms of this metal via inhalation or ingestion. Following exposure, mercuric ions are taken up by and accumulate in numerous organs, including brain, intestine, kidney, liver, and placenta. In order to understand the toxicological effects of exposure to mercury, a thorough understanding of the mechanisms that facilitate entry of mercuric ions into target cells must first be obtained. A number of mechanisms for the transport of mercuric ions into target cells and organs have been proposed in recent years. However, the ability of these mechanisms to transport mercuric ions and the regulatory features of these carriers have not been characterized completely. The purpose of this review is to summarize the current findings related to the mechanisms that may be involved in the transport of inorganic and organic forms of mercury in target tissues and organs. This review will describe mechanisms known to be involved in the transport of mercury and will also propose additional mechanisms that may potentially be involved in the transport of mercuric ions into target cells. PMID:27422290

32 CFR 199.24 - TRICARE Reserve Select.

Science.gov (United States)

2010-07-01

...) MISCELLANEOUS CIVILIAN HEALTH AND MEDICAL PROGRAM OF THE UNIFORMED SERVICES (CHAMPUS) § 199.24 TRICARE Reserve... rules and procedures as may be appropriate to the area involved. (4) Terminology. Certain terminology is...

Mercury's exosphere: observations during MESSENGER's First Mercury flyby.

Science.gov (United States)

McClintock, William E; Bradley, E Todd; Vervack, Ronald J; Killen, Rosemary M; Sprague, Ann L; Izenberg, Noam R; Solomon, Sean C

2008-07-04

During MESSENGER's first Mercury flyby, the Mercury Atmospheric and Surface Composition Spectrometer measured Mercury's exospheric emissions, including those from the antisunward sodium tail, calcium and sodium close to the planet, and hydrogen at high altitudes on the dayside. Spatial variations indicate that multiple source and loss processes generate and maintain the exosphere. Energetic processes connected to the solar wind and magnetospheric interaction with the planet likely played an important role in determining the distributions of exospheric species during the flyby.

Baseline mercury and zinc concentrations in terrestrial and coastal organisms of Admiralty Bay, Antarctica

International Nuclear Information System (INIS)

Rodrigues dos Santos, Isaac; Silva-Filho, Emmanoel Vieira; Schaefer, Carlos; Maria Sella, Silvia; Silva, Carlos A.; Gomes, Vicente; Passos, Maria Jose de A.C.R.; Phan Van Ngan

2006-01-01

This paper provides the first quantitative information on mercury in soil, coastal sediment, and in characteristic organisms of terrestrial and shallow coastal marine ecosystems from Admiralty Bay (King George Island, Antarctica). As expected for a remote area, mercury content is low in abiotic components of the ecosystem, and probably similar to natural levels. Mercury also occurs in very low concentrations in the vegetation, invertebrates and fish. These low mercury levels may be due to sulphide formation in reducing sediments of this environment. Higher concentrations of mercury occurred in bird feathers and mammal hair, indicating biomagnification. This was not found for Zinc. These results may be useful as a reference background to detect future inputs of trace elements in this remote area of the earth. Terrestrial vegetation and bird feathers are suggested as target regional biomonitors. - Low levels of mercury and zinc occurred in soil and plant samples from Antarctica, but high levels occurred in birds and mammals

Spallation neutron source target station design, development, and commissioning

Energy Technology Data Exchange (ETDEWEB)

Haines, J.R., E-mail: hainesjr@ornl.gov; McManamy, T.J.; Gabriel, T.A.; Battle, R.E.; Chipley, K.K.; Crabtree, J.A.; Jacobs, L.L.; Lousteau, D.C.; Rennich, M.J.; Riemer, B.W.

2014-11-11

The spallation neutron source target station is designed to safely, reliably, and efficiently convert a 1 GeV beam of protons to a high flux of about 1 meV neutrons that are available at 24 neutron scattering instrument beam lines. Research and development findings, design requirements, design description, initial checkout testing, and results from early operation with beam are discussed for each of the primary target subsystems, including the mercury target, neutron moderators and reflector, surrounding vessels and shielding, utilities, remote handling equipment, and instrumentation and controls. Future plans for the mercury target development program are also briefly discussed.

21 CFR 1.99 - Costs chargeable in connection with relabeling and reconditioning inadmissible imports.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Costs chargeable in connection with relabeling and reconditioning inadmissible imports. 1.99 Section 1.99 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL GENERAL ENFORCEMENT REGULATIONS Imports and Exports § 1.99 Costs...

A mercury transport and fate model (LM2-mercury) for mass budget assessment of mercury cycling in Lake Michigan

Science.gov (United States)

LM2-Mercury, a mercury mass balance model, was developed to simulate and evaluate the transport, fate, and biogeochemical transformations of mercury in Lake Michigan. The model simulates total suspended solids (TSS), disolved organic carbon (DOC), and total, elemental, divalent, ...

Mercury Emission Measurement in Coal-Fired Boilers by Continuous Mercury Monitor and Ontario Hydro Method

Science.gov (United States)

Zhu, Yanqun; Zhou, Jinsong; He, Sheng; Cai, Xiaoshu; Hu, Changxin; Zheng, Jianming; Zhang, Le; Luo, Zhongyang; Cen, Kefa

2007-06-01

The mercury emission control approach attaches more importance. The accurate measurement of mercury speciation is a first step. Because OH method (accepted method) can't provide the real-time data and 2-week time for results attained, it's high time to seek on line mercury continuous emission monitors(Hg-CEM). Firstly, the gaseous elemental and oxidized mercury were conducted to measure using OH and CEM method under normal operation conditions of PC boiler after ESP, the results between two methods show good consistency. Secondly, through ESP, gaseous oxidized mercury decrease a little and particulate mercury reduce a little bit, but the elemental mercury is just the opposite. Besides, the WFGD system achieved to gaseous oxidized mercury removal of 53.4%, gaseous overall mercury and elemental mercury are 37.1% and 22.1%, respectively.

Global Sources and Pathways of Mercury in the Context of Human Health

Directory of Open Access Journals (Sweden)

Kyrre Sundseth

2017-01-01

Full Text Available This paper reviews information from the existing literature and the EU GMOS (Global Mercury Observation System project to assess the current scientific knowledge on global mercury releases into the atmosphere, on global atmospheric transport and deposition, and on the linkage between environmental contamination and potential impacts on human health. The review concludes that assessment of global sources and pathways of mercury in the context of human health is important for being able to monitor the effects from implementation of the Minamata Convention targets, although new research is needed on the improvement of emission inventory data, the chemical and physical behaviour of mercury in the atmosphere, the improvement of monitoring network data, predictions of future emissions and speciation, and on the subsequent effects on the environment, human health, as well as the economic costs and benefits of reducing these aspects.

Mercury in canned tuna: white versus light and temporal variation

International Nuclear Information System (INIS)

Burger, Joanna; Gochfeld, Michael

2004-01-01

mercury. These data indicate that people who eat canned tuna frequently can choose light tuna and reduce their mercury intake. Canned mackerel had much lower levels of mercury than tuna. Since cans of white tuna frequently exceed the FDA's original action level of 0.5 ppm, it would be prudent to continue some systematic monitoring of the nation's canned fish supply, particularly as the targets of commercial fisheries inevitably change as certain stocks become depleted

Biomarkers of mercury exposure at a mercury recycling facility in Ukraine

Science.gov (United States)

Gibb, H.J.; Kozlov, K.; Buckley, J.P.; Centeno, J.; Jurgenson, V.; Kolker, A.; Conko, K.; Landa, E.; Panov, B.; Panov, Y.; Xu, H.

2008-01-01

This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those who worked at the facility but not in the yard where the recycling was done (Group B, n = 14), and (3) those who did not work at the facility (Group C, n = 7). Urine, blood, hair, and nail samples were collected from the participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in the former mercury mine/smelter located on the site of the recycling facility. Each factor was tested in a univariate regression with total mercury in urine, blood, hair, and nails. Median biomarker concentrations were 4.04 ??g/g-Cr (urine), 2.58 ??g/L (blood), 3.95 ??g/g (hair), and 1.16 ??g/g (nails). Occupational category was significantly correlated (p < 0.001) with both blood and urinary mercury concentrations but not with hair or nail mercury. Four individuals had urinary mercury concentrations in a range previously found to be associated with subtle neurological and subjective symptoms (e.g., fatigue, loss of appetite, irritability), and one worker had a urinary mercury concentration in a range associated with a high probability of neurological effects and proteinuria. Comparison of results by occupational category found that workers directly involved with the recycling operation had the highest blood and urinary mercury levels. Those who worked at the facility but were not directly involved with the recycling operation had higher levels than those who did not work at the facility. Copyright ?? 2008 JOEH, LLC.

Concentration of mercury in wheat samples stored with mercury tablets as preservative

International Nuclear Information System (INIS)

Lalit, B.Y.; Ramachandran, T.V.

1977-01-01

Tablets consisting of mercury in the form of a dull grey powder made by triturating mercury with chalk and sugar are used in Indian household for storing food-grains. The contamination of wheat samples by mercury, when stored with mercury tablets for period of upto four years has been assessed by using non-destructive neutron activation analysis. The details of the analytical procedure used have also been briefly described. The concentration of mercury in wheat increases with storage period. Loss of weight of mercury tablet is proportional to the storage period to a first approximation. In the present experiment, the average weight loss at the and end of first year was 0.009716 g corresponding to 6 ppm in wheat. (T.G.)

32 CFR 199.12 - Third party recoveries.

Science.gov (United States)

2010-07-01

... of § 199.10 of this part. However, the proper exercise of the right to appeal benefit or provider... (including amounts paid by TRICARE for both inpatient and outpatient care). Prior to assertion and final...

Mercury Flow Through the Mercury-Containing Lamp Sector of the Economy of the United States

Science.gov (United States)

Goonan, Thomas G.

2006-01-01

Introduction: This Scientific Investigations Report examines the flow of mercury through the mercury-containing lamp sector of the U.S. economy in 2001 from lamp manufacture through disposal or recycling. Mercury-containing lamps illuminate commercial and industrial buildings, outdoor areas, and residences. Mercury is an essential component in fluorescent lamps and high-intensity discharge lamps (high-pressure sodium, mercury-vapor, and metal halide). A typical fluorescent lamp is composed of a phosphor-coated glass tube with electrodes located at either end. Only a very small amount of the mercury is in vapor form. The remainder of the mercury is in the form of either liquid mercury metal or solid mercury oxide (mercury oxidizes over the life of the lamp). When voltage is applied, the electrodes energize the mercury vapor and cause it to emit ultraviolet energy. The phosphor coating absorbs the ultraviolet energy, which causes the phosphor to fluoresce and emit visible light. Mercury-containing lamps provide more lumens per watt than incandescent lamps and, as a result, require from three to four times less energy to operate. Mercury is persistent and toxic within the environment. Mercury-containing lamps are of environmental concern because they are widely distributed throughout the environment and are easily broken in handling. The magnitude of lamp sector mercury emissions, estimated to be 2.9 metric tons per year (t/yr), is small compared with the estimated mercury losses of the U.S. coal-burning and chlor-alkali industries, which are about 70 t/yr and about 90 t/yr, respectively.

Estimating mercury emissions from a zinc smelter in relation to China's mercury control policies

International Nuclear Information System (INIS)

Wang, S.X.; Song, J.X.; Li, G.H.; Wu, Y.; Zhang, L.; Wan, Q.; Streets, D.G.; Chin, Conrad K.; Hao, J.M.

2010-01-01

Mercury concentrations of flue gas at inlet/outlet of the flue gas cleaning, electrostatic demister, reclaiming tower, acid plant, and mercury contents in zinc concentrate and by-products were measured in a hydrometallurgical zinc smelter. The removal efficiency of flue gas cleaning, electrostatic demister, mercury reclaiming and acid plant was about 17.4%, 30.3%, 87.9% and 97.4% respectively. Flue gas cleaning and electrostatic demister captured 11.7% and 25.3% of the mercury in the zinc concentrate, respectively. The mercury reclaiming tower captured 58.3% of the mercury in the zinc concentrate. About 4.2% of the mercury in the zinc concentrate was captured by the acid plant. Consequently, only 0.8% of the mercury in the zinc concentrate was emitted to the atmosphere. The atmospheric mercury emission factor was 0.5 g t -1 of zinc produced for the tested smelter, indicating that this process offers the potential to effectively reduce mercury emissions from zinc smelting. - Modern scale production equipped with acid plant and Hg reclaiming tower will significantly reduce Hg emissions from zinc smelters in China.

Reduced Limit on the Permanent Electric Dipole Moment of ^{199}Hg.

Science.gov (United States)

Graner, B; Chen, Y; Lindahl, E G; Heckel, B R

2016-04-22

This Letter describes the results of the most recent measurement of the permanent electric dipole moment (EDM) of neutral ^{199}Hg atoms. Fused silica vapor cells containing enriched ^{199}Hg are arranged in a stack in a common magnetic field. Optical pumping is used to spin polarize the atoms orthogonal to the applied magnetic field, and the Faraday rotation of near-resonant light is observed to determine an electric-field-induced perturbation to the Larmor precession frequency. Our results for this frequency shift are consistent with zero; we find the corresponding ^{199}Hg EDM d_{Hg}=(-2.20±2.75_{stat}±1.48_{syst})×10^{-30}e cm. We use this result to place a new upper limit on the ^{199}Hg EDM |d_{Hg}|<7.4×10^{-30}e cm (95% C.L.), improving our previous limit by a factor of 4. We also discuss the implications of this result for various CP-violating observables as they relate to theories of physics beyond the standard model.

Spatial variation of mercury bioaccumulation in bats of Canada linked to atmospheric mercury deposition.

Science.gov (United States)

Chételat, John; Hickey, M Brian C; Poulain, Alexandre J; Dastoor, Ashu; Ryjkov, Andrei; McAlpine, Donald; Vanderwolf, Karen; Jung, Thomas S; Hale, Lesley; Cooke, Emma L L; Hobson, Dave; Jonasson, Kristin; Kaupas, Laura; McCarthy, Sara; McClelland, Christine; Morningstar, Derek; Norquay, Kaleigh J O; Novy, Richard; Player, Delanie; Redford, Tony; Simard, Anouk; Stamler, Samantha; Webber, Quinn M R; Yumvihoze, Emmanuel; Zanuttig, Michelle

2018-06-01

Wildlife are exposed to neurotoxic mercury at locations distant from anthropogenic emission sources because of long-range atmospheric transport of this metal. In this study, mercury bioaccumulation in insectivorous bat species (Mammalia: Chiroptera) was investigated on a broad geographic scale in Canada. Fur was analyzed (n=1178) for total mercury from 43 locations spanning 20° latitude and 77° longitude. Total mercury and methylmercury concentrations in fur were positively correlated with concentrations in internal tissues (brain, liver, kidney) for a small subset (n=21) of little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus), validating the use of fur to indicate internal mercury exposure. Brain methylmercury concentrations were approximately 10% of total mercury concentrations in fur. Three bat species were mainly collected (little brown bats, big brown bats, and northern long-eared bats [M. septentrionalis]), with little brown bats having lower total mercury concentrations in their fur than the other two species at sites where both species were sampled. On average, juvenile bats had lower total mercury concentrations than adults but no differences were found between males and females of a species. Combining our dataset with previously published data for eastern Canada, median total mercury concentrations in fur of little brown bats ranged from 0.88-12.78μg/g among 11 provinces and territories. Highest concentrations were found in eastern Canada where bats are most endangered from introduced disease. Model estimates of atmospheric mercury deposition indicated that eastern Canada was exposed to greater mercury deposition than central and western sites. Further, mean total mercury concentrations in fur of adult little brown bats were positively correlated with site-specific estimates of atmospheric mercury deposition. This study provides the largest geographic coverage of mercury measurements in bats to date and indicates that atmospheric

Metallic mercury recycling. Final report

Energy Technology Data Exchange (ETDEWEB)

Beck, M.A.

1994-07-01

Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made.

Metallic mercury recycling. Final report

International Nuclear Information System (INIS)

Beck, M.A.

1994-01-01

Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made

Mercury(II) and methyl mercury speciation on Streptococcus pyogenes loaded Dowex Optipore SD-2

International Nuclear Information System (INIS)

Tuzen, Mustafa; Uluozlu, Ozgur Dogan; Karaman, Isa; Soylak, Mustafa

2009-01-01

A solid phase extraction procedure based on speciation of mercury(II) and methyl mercury on Streptococcus pyogenes immobilized on Dowex Optipore SD-2 has been established. Selective and sequential elution with 0.1 mol L -1 HCl for methyl mercury and 2 mol L -1 HCl for mercury(II) were performed at pH 8. The determination of mercury levels was performed by cold vapour atomic absorption spectrometry (CVAAS). Optimal analytical conditions including pH, amounts of biosorbent, sample volumes, etc., were investigated. The influences of the some alkaline and earth alkaline ions and some transition metals on the recoveries were also investigated. The capacity of biosorbent for mercury(II) and methyl mercury was 4.8 and 3.4 mg g -1 . The detection limit (3 sigma) of the reagent blank for mercury(II) and methyl mercury was 2.1 and 1.5 ng L -1 . Preconcentration factor was calculated as 25. The relative standard deviations of the procedure were below 7%. The validation of the presented procedure is performed by the analysis of standard reference material (NRCC-DORM 2 Dogfish Muscle). The procedure was successfully applied to the speciation of mercury(II) and methyl mercury in natural water and environmental samples.

Mercury(II) and methyl mercury speciation on Streptococcus pyogenes loaded Dowex Optipore SD-2

Energy Technology Data Exchange (ETDEWEB)

Tuzen, Mustafa, E-mail: m.tuzen@gmail.com [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Uluozlu, Ozgur Dogan [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Karaman, Isa [Gaziosmanpasa University, Faculty of Science and Arts, Biology Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)

2009-09-30

A solid phase extraction procedure based on speciation of mercury(II) and methyl mercury on Streptococcus pyogenes immobilized on Dowex Optipore SD-2 has been established. Selective and sequential elution with 0.1 mol L{sup -1} HCl for methyl mercury and 2 mol L{sup -1} HCl for mercury(II) were performed at pH 8. The determination of mercury levels was performed by cold vapour atomic absorption spectrometry (CVAAS). Optimal analytical conditions including pH, amounts of biosorbent, sample volumes, etc., were investigated. The influences of the some alkaline and earth alkaline ions and some transition metals on the recoveries were also investigated. The capacity of biosorbent for mercury(II) and methyl mercury was 4.8 and 3.4 mg g{sup -1}. The detection limit (3 sigma) of the reagent blank for mercury(II) and methyl mercury was 2.1 and 1.5 ng L{sup -1}. Preconcentration factor was calculated as 25. The relative standard deviations of the procedure were below 7%. The validation of the presented procedure is performed by the analysis of standard reference material (NRCC-DORM 2 Dogfish Muscle). The procedure was successfully applied to the speciation of mercury(II) and methyl mercury in natural water and environmental samples.

Thiosulphate assisted phytoextraction of mercury contaminated soils at the Wanshan Mercury Mining District, Southwest China

Directory of Open Access Journals (Sweden)

J. Wang

2013-10-01

Full Text Available Wanshan, known as the “Mercury Capital” of China, is located in the Southwest of China. Due to the extensive mining and smelting works in the Wanshan area, the local ecosystem has been serious contaminated with mercury. In the present study, a number of soil samples were taken from the Wanshan mercury mining area and the mercury fractionations in soils were analyzed using sequential extraction procedure technique. The obtained results showed that the dominate mercury fractions (represent 95% of total mercury were residual and organic bound mercury. A field trial was conducted in a mercury polluted farmland at the Wanshan mercury mine. Four plant species Brassica juncea Czern. et Coss.var. ASKYC (ASKYC, Brassica juncea Czern. et Coss.var.DPDH (DPDH, Brassica juncea Czern. et Coss.var.CHBD(CHBD, Brassica juncea Czern. et Coss.var.LDZY (LDZY were tested their ability to extract mercury from soil with thiosulphate amendment. The results indicated that the mercury concentration in the roots and shoots of the four plants were significantly increased with thiosulphate treatment. The mercury phytoextraction yield of ASKYC, DPDH, CHBD and LDZY were 92, 526, 294 and 129 g/ha, respectively

Thiosulphate assisted phytoextraction of mercury contaminated soils at the Wanshan Mercury Mining District, Southwest China

Directory of Open Access Journals (Sweden)

J Wang

2013-10-01

Full Text Available Wanshan, known as the “Mercury Capital” of China, is located in the Southwest of China. Due to the extensive mining and smelting works in the Wanshan area, the local ecosystem has been serious contaminated with mercury. In the present study, a number of soil samples were taken from the Wanshan mercury mining area and the mercury fractionations in soils were analyzed using sequential extraction procedure technique. The obtained results showed that the dominate mercury fractions (represent 95% of total mercury were residual and organic bound mercury. A field trial was conducted in a mercury polluted farmland at the Wanshan mercury mine. Four plant species Brassica juncea Czern. et Coss.var. ASKYC (ASKYC, Brassica juncea Czern. et Coss.var.DPDH (DPDH, Brassica juncea Czern. et Coss.var.CHBD(CHBD, Brassica juncea Czern. et Coss.var.LDZY (LDZY were tested their ability to extract mercury from soil with thiosulphate amendment. The results indicated that the mercury concentration in the roots and shoots of the four plants were significantly increased with thiosulphate treatment. The mercury phytoextraction yield of ASKYC, DPDH, CHBD and LDZY were 92, 526, 294 and 129 g/ha, respectively.

Polymeric nanoparticle-based delivery of microRNA-199a-3p inhibits proliferation and growth of osteosarcoma cells

Directory of Open Access Journals (Sweden)

Zhang L

2015-04-01

Full Text Available Linlin Zhang,1,2,* Arun K lyer,3,4,* Xiaoqian Yang,1 Eisuke Kobayashi,1 Yuqi Guo,1,2 Henry Mankin,1 Francis J Hornicek,1 Mansoor M Amiji,3 Zhenfeng Duan1 1Sarcoma Biology Laboratory, Center for Sarcoma and Connective Tissue Oncology, Massachusetts General Hospital, Boston, Massachusetts, USA; 2Department of Pathology, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China; 3Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, Massachusetts, USA; 4Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA *These authors contributed equally to this work Abstract: Our prior screening of microRNAs (miRs identified that miR-199a-3p expression is reduced in osteosarcoma cells, one of the most common types of bone tumor. miR-199a-3p exhibited functions of tumor cell growth inhibition, suggesting the potential application of miR-199a-3p as an anticancer agent. In the study reported here, we designed and developed a lipid-modified dextran-based polymeric nanoparticle platform for encapsulation of miRs, and determined the efficiency and efficacy of delivering miR-199a-3p into osteosarcoma cells. In addition, another potent miR, let-7a, which also displayed tumor suppressive ability, was selected as a candidate miR for evaluation. Fluorescence microscopy studies and real-time polymerase chain reaction results showed that dextran nanoparticles could deliver both miR-199a-3p and let-7a into osteosarcoma cell lines (KHOS and U-2OS successfully. Western blotting analysis and 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assays demonstrated that dextran nanoparticles loaded with miRs could efficiently downregulate the expression of target proteins and effectively inhibit the growth and proliferation of osteosarcoma cells. These results demonstrate that a lipid-modified dextran

Mercury CEM Calibration

Energy Technology Data Exchange (ETDEWEB)

John Schabron; Joseph Rovani; Mark Sanderson

2008-02-29

Mercury continuous emissions monitoring systems (CEMS) are being implemented in over 800 coal-fired power plant stacks. The power industry desires to conduct at least a full year of monitoring before the formal monitoring and reporting requirement begins on January 1, 2009. It is important for the industry to have available reliable, turnkey equipment from CEM vendors. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The generators are used to calibrate mercury CEMs at power plant sites. The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005 requires that calibration be performed with NIST-traceable standards (Federal Register 2007). Traceability procedures will be defined by EPA. An initial draft traceability protocol was issued by EPA in May 2007 for comment. In August 2007, EPA issued an interim traceability protocol for elemental mercury generators (EPA 2007). The protocol is based on the actual analysis of the output of each calibration unit at several concentration levels ranging initially from about 2-40 {micro}g/m{sup 3} elemental mercury, and in the future down to 0.2 {micro}g/m{sup 3}, and this analysis will be directly traceable to analyses by NIST. The document is divided into two separate sections. The first deals with the qualification of generators by the vendors for use in mercury CEM calibration. The second describes the procedure that the vendors must use to certify the generator models that meet the qualification specifications. The NIST traceable certification is performance based, traceable to analysis using isotope dilution inductively coupled plasma/mass spectrometry performed by NIST in Gaithersburg, MD. The

Accumulation of mercury in selected plant species grown in soils contaminated with different mercury compounds

International Nuclear Information System (INIS)

Su, Yi; Han, Fengxiang; Shiyab, Safwan; Chen, Jian; Monts, David L.

2007-01-01

The objective of our research is to screen and search for suitable plant species for phyto-remediation of mercury-contaminated soil. Currently our effort is specifically focused on mercury removal from the U.S. Department of Energy (DOE) sites, where mercury contamination is a major concern. In order to cost effectively implement mercury remediation efforts, it is necessary now to obtain an improved understanding of biological means of removing mercury and mercury compounds.. Phyto-remediation is a technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. In particular, phyto-extraction is the uptake of contaminants by plant roots and translocation within the plants to shoots or leaves. Contaminants are generally removed by harvesting the plants. We have investigated phyto-extraction of mercury from contaminated soil by using some of the known metal-accumulating plants since no natural plant species with mercury hyper-accumulating properties has yet been identified. Different natural plant species have been studied for mercury uptake, accumulation, toxicity and overall mercury removal efficiency. Various mercury compounds, such as HgS, HgCl 2 , and Hg(NO 3 ) 2 , were used as contaminant sources. Different types of soil were examined and chosen for phyto-remediation experiments. We have applied microscopy and diffuse reflectance spectrometry as well as conventional analytical chemistry to monitor the phyto-remediation processes of mercury uptake, translocation and accumulation, and the physiological impact of mercury contaminants on selected plant species. Our results indicate that certain plant species, such as beard grass (Polypogon monospeliensis), accumulated a very limited amount of mercury in the shoots ( 2 powder, respectively; no visual stress symptoms were observed. We also studied mercury phyto-remediation using aged soils that contained HgS, HgCl 2 , or Hg(NO 3 ) 2 . We have found that up to hundreds

Methyl mercury, but not inorganic mercury, associated with higher blood pressure during pregnancy.

Science.gov (United States)

Wells, Ellen M; Herbstman, Julie B; Lin, Yu Hong; Hibbeln, Joseph R; Halden, Rolf U; Witter, Frank R; Goldman, Lynn R

2017-04-01

Prior studies addressing associations between mercury and blood pressure have produced inconsistent findings; some of this may result from measuring total instead of speciated mercury. This cross-sectional study of 263 pregnant women assessed total mercury, speciated mercury, selenium, and n-3 polyunsaturated fatty acids in umbilical cord blood and blood pressure during labor and delivery. Models with a) total mercury or b) methyl and inorganic mercury were evaluated. Regression models adjusted for maternal age, race/ethnicity, prepregnancy body mass index, neighborhood income, parity, smoking, n-3 fatty acids and selenium. Geometric mean total, methyl, and inorganic mercury concentrations were 1.40µg/L (95% confidence interval: 1.29, 1.52); 0.95µg/L (0.84, 1.07); and 0.13µg/L (0.10, 0.17), respectively. Elevated systolic BP, diastolic BP, and pulse pressure were found, respectively, in 11.4%, 6.8%, and 19.8% of mothers. In adjusted multivariable models, a one-tertile increase of methyl mercury was associated with 2.83mmHg (0.17, 5.50) higher systolic blood pressure and 2.99mmHg (0.91, 5.08) higher pulse pressure. In the same models, an increase of one tertile of inorganic mercury was associated with -1.18mmHg (-3.72, 1.35) lower systolic blood pressure and -2.51mmHg (-4.49, -0.53) lower pulse pressure. No associations were observed with diastolic pressure. There was a non-significant trend of higher total mercury with higher systolic blood pressure. We observed a significant association of higher methyl mercury with higher systolic and pulse pressure, yet higher inorganic mercury was significantly associated with lower pulse pressure. These results should be confirmed with larger, longitudinal studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Mercury and halogens in coal--Their role in determining mercury emissions from coal combustion

Science.gov (United States)

Kolker, Allan; Quick, Jeffrey C.; Senior, Connie L.; Belkin, Harvey E.

2012-01-01

Mercury is a toxic pollutant. In its elemental form, gaseous mercury has a long residence time in the atmosphere, up to a year, allowing it to be transported long distances from emission sources. Mercury can be emitted from natural sources such as volcanoes, or from anthropogenic sources, such as coal-fired powerplants. In addition, all sources of mercury on the Earth's surface can re-emit it from land and sea back to the atmosphere, from which it is then redeposited. Mercury in the atmosphere is present in such low concentrations that it is not considered harmful. Once mercury enters the aquatic environment, however, it can undergo a series of biochemical transformations that convert a portion of the mercury originally present to methylmercury, a highly toxic organic form of mercury that accumulates in fish and birds. Many factors contribute to creation of methylmercury in aquatic ecosystems, including mercury availability, sediment and nutrient load, bacterial influence, and chemical conditions. In the United States, consumption of fish with high levels of methylmercury is the most common pathway for human exposure to mercury, leading the U.S. Environmental Protection Agency (EPA) to issue fish consumption advisories in every State. The EPA estimates that 50 percent of the mercury entering the atmosphere in the United States is emitted from coal-burning utility powerplants. An EPA rule, known as MATS (for Mercury and Air Toxics Standards), to reduce emissions of mercury and other toxic pollutants from powerplants, was signed in December 2011. The rule, which is currently under review, specifies limits for mercury and other toxic elements, such as arsenic, chromium, and nickel. MATS also places limits on emission of harmful acid gases, such as hydrochloric acid and hydrofluoric acid. These standards are the result of a 2010 detailed nationwide program by the EPA to sample stack emissions and thousands of shipments of coal to coal-burning powerplants. The United

Modeling Mercury in Proteins

Energy Technology Data Exchange (ETDEWEB)

Smith, Jeremy C [ORNL; Parks, Jerry M [ORNL

2016-01-01

Mercury (Hg) is a naturally occurring element that is released into the biosphere both by natural processes and anthropogenic activities. Although its reduced, elemental form Hg(0) is relatively non-toxic, other forms such as Hg2+ and, in particular, its methylated form, methylmercury, are toxic, with deleterious effects on both ecosystems and humans. Microorganisms play important roles in the transformation of mercury in the environment. Inorganic Hg2+ can be methylated by certain bacteria and archaea to form methylmercury. Conversely, bacteria also demethylate methylmercury and reduce Hg2+ to relatively inert Hg(0). Transformations and toxicity occur as a result of mercury interacting with various proteins. Clearly, then, understanding the toxic effects of mercury and its cycling in the environment requires characterization of these interactions. Computational approaches are ideally suited to studies of mercury in proteins because they can provide a detailed picture and circumvent issues associated with toxicity. Here we describe computational methods for investigating and characterizing how mercury binds to proteins, how inter- and intra-protein transfer of mercury is orchestrated in biological systems, and how chemical reactions in proteins transform the metal. We describe quantum chemical analyses of aqueous Hg(II), which reveal critical factors that determine ligand binding propensities. We then provide a perspective on how we used chemical reasoning to discover how microorganisms methylate mercury. We also highlight our combined computational and experimental studies of the proteins and enzymes of the mer operon, a suite of genes that confers mercury resistance in many bacteria. Lastly, we place work on mercury in proteins in the context of what is needed for a comprehensive multi-scale model of environmental mercury cycling.

Mercury is Moon's brother

International Nuclear Information System (INIS)

Ksanfomalifi, L.V.

1976-01-01

The latest information on Mercury planet is presented obtained by studying the planet with the aid of radar and space vehicles. Rotation of Mercury about its axis has been discovered; within 2/3 of its year it executes a complete revolution about its axis. In images obtained by the ''Mariner-10'' Mercurys surface differs little from that of the Moon. The ''Mariner-10'' has also discovered the Mercurys atmosphere, which consists of extremely rarefied helium. The helium is continuously supplied to the planet by the solar wind. The Mercury's magnetic field has been discovered, whose strength is 35 x 10 -4 at the Equator and 70 x 10 -4 E at the poles. The inclination of the dipole axis to the Mercury's rotation axis is 7 deg

Mercury nano-trap for effective and efficient removal of mercury(II) from aqueous solution

Science.gov (United States)

Li, Baiyan; Zhang, Yiming; Ma, Dingxuan; Shi, Zhan; Ma, Shengqian

2014-11-01

Highly effective and highly efficient decontamination of mercury from aqueous media remains a serious task for public health and ecosystem protection. Here we report that this task can be addressed by creating a mercury ‘nano-trap’ as illustrated by functionalizing a high surface area and robust porous organic polymer with a high density of strong mercury chelating groups. The resultant porous organic polymer-based mercury ‘nano-trap’ exhibits a record-high saturation mercury uptake capacity of over 1,000 mg g-1, and can effectively reduce the mercury(II) concentration from 10 p.p.m. to the extremely low level of smaller than 0.4 p.p.b. well below the acceptable limits in drinking water standards (2 p.p.b.), and can also efficiently remove >99.9% mercury(II) within a few minutes. Our work therefore presents a new benchmark for mercury adsorbent materials and provides a new perspective for removing mercury(II) and also other heavy metal ions from contaminated water for environmental remediation.

Study of high levels indoor air mercury contamination from mercury amalgam use in dentistry

International Nuclear Information System (INIS)

Khwaja, M.A.; Abbasi, M.S.; Mehmood, F.; Jahangir, S.

2014-01-01

In 2005, United Nations Environment Programme (UNEP) estimated that 362 tonnes of dental mercury are consumed annually worldwide. Dental mercury amalgams also called silver fillings and amalgam fillings are widely done. These fillings gave off mercury vapours. Estimated average absorbed concentrations of mercury vapours from dental fillings vary from 3,000 to 17,000 ng Hg. Mercury (Hg) also known as quick silver is an essential constituent of dental amalgam. It is a toxic substance of global concern. A persistent pollutant, mercury is not limited to its source but it travels, on time thousands of kilometers away from the source. Scientific evidence, including, UNEP Global Mercury report, establishes mercury as an extremely toxic substance, which is a major threat to wildlife, ecosystem and human health, at a global scale. Children are more at risk from mercury poisoning which affects their neurological development and brain. Mercury poisoning diminishes memory, attention, thinking and sight. In the past, a number of studies at dental sites in many countries have been carried out and reported which have been reviewed and briefly described. This paper describes and discusses the recent investigations, regarding mercury vapours level in air, carried out at 18 dental sites in Pakistan and other countries. It is evident from the data of 42 dental sites in 17 countries, including, selected dental sites in five main cities of Pakistan, described and discussed in this paper that at most dental sites in many countries including Pakistan, the indoor mercury vapours levels exceed far above the permissible limit, recommended for safe physical and mental health. At these sites, public, in general, and the medical, paramedical staff and vulnerable population, in particular, are at most serious risk to health resulting from exposure to toxic and hazardous mercury. (author)

Concentration of mercury in wheat samples stored with mercury tablets as preservative. [Neutrons

Energy Technology Data Exchange (ETDEWEB)

Lalit, B Y; Ramachandran, T V [Bhabha Atomic Research Centre, Bombay (India). Air Monitoring Section

1977-01-01

Tablets consisting of mercury in the form of a dull grey powder made by triturating mercury with chalk and sugar are used in Indian household for storing food-grains. The contamination of wheat samples by mercury, when stored with mercury tablets for period of upto four years has been assessed by using non-destructive neutron activation analysis. The details of the analytical procedure used have also been briefly described. The concentration of mercury in wheat increases with storage period. Loss of weight of mercury tablet is proportional to the storage period to a first approximation. In the present experiment, the average weight loss at the and end of first year was 0.009716 g corresponding to 6 ppm in wheat.

Depletion of atmospheric gaseous elemental mercury by plant uptake at Mt. Changbai, Northeast China

Directory of Open Access Journals (Sweden)

X. Fu

2016-10-01

Full Text Available There exists observational evidence that gaseous elemental mercury (GEM can be readily removed from the atmosphere via chemical oxidation followed by deposition in the polar and sub-polar regions, free troposphere, lower stratosphere, and marine boundary layer under specific environmental conditions. Here we report GEM depletions in a temperate mixed forest at Mt. Changbai, Northeast China. The strong depletions occurred predominantly at night during the leaf-growing season and in the absence of gaseous oxidized mercury (GOM enrichment (GOM  <  3 pg m−3. Vertical gradients of decreasing GEM concentrations from layers above to under forest canopy suggest in situ loss of GEM to forest canopy at Mt. Changbai. Foliar GEM flux measurements showed that the foliage of two predominant tree species is a net sink of GEM at night, with a mean flux of −1.8 ± 0.3 ng m2 h−1 over Fraxinus mandshurica (deciduous tree species and −0.1 ± 0.2 ng m2 h−1 over Pinus Koraiensis (evergreen tree species. Daily integrated GEM δ202Hg, Δ199Hg, and Δ200Hg at Mt. Changbai during 8–18 July 2013 ranged from −0.34 to 0.91 ‰, from −0.11 to −0.04 ‰ and from −0.06 to 0.01 ‰, respectively. A large positive shift in GEM δ202Hg occurred during the strong GEM depletion events, whereas Δ199Hg and Δ200Hg remained essentially unchanged. The observational findings and box model results show that uptake of GEM by forest canopy plays a predominant role in the GEM depletion at Mt. Changbai forest. Such depletion events of GEM are likely to be a widespread phenomenon, suggesting that the forest ecosystem represents one of the largest sinks ( ∼ 1930 Mg of atmospheric Hg on a global scale.

Radioactive mercury distribution in biological fluids and excretion in human subjects after inhalation of mercury vapor

International Nuclear Information System (INIS)

Cherian, M.G.; Hursh, J.B.; Clarkson, T.W.; Allen, J.

1978-01-01

The distribution of mercury in red blood cells (RBCs) and plasma, and its excretion in urine and feces are described in five human subjects during the first 7 days following inhalation of radioactive mercury vapor. A major portion (98%) of radioactive mercury in whole blood is initially accumulated in the RBCs and is transferred partly to the plasma compartment until the ratio of mercury in RBCs to plasma is about 2 within 20 h. The cumulative urinary and fecal excretion of mercury for 7 days is about 11.6% of the retained dose, and is closely related to the percent decline in body burden of mercury. There is little correlation between either the urinary excretion and plasma radioactivity of mercury, or the specific activities of urine and plasma mercury, suggesting a mechanism other than a direct glomerular filtration involved in the urinary excretion of recently exposed mercury. These studies suggest that blood mercury levels can be used as an index of recent exposure, while urinary levels may be an index of renal concentration of mercury. However, there is no reliable index for mercury concentration in the brain

FINAL REPORT ON THE AQUATIC MERCURY ASSESSMENT STUDY

Energy Technology Data Exchange (ETDEWEB)

Halverson, N

2008-09-30

. Methylmercury ranged from 0.002 ng/l in Upper Three Runs to 2.60 ng/l in Tims Branch. Total mercury in the Savannah River ranged from 0.62 ng/l to 43.9 ng/l, and methylmercury ranged from 0.036 ng/l to 7.54 ng/l. Both total and methylmercury concentrations were consistently high in the river near the mouth of Steel Creek. Total mercury was positively correlated with methylmercury (r = 0.88). Total mercury bound to particulates ranged from 41% to 57% in the river and from 28% to 90% in the streams. Particulate methylmercury varied from 9% to 37% in the river and from 6% to 79% in the streams. Small temporary pools in the Savannah River swamp area near and around Fourmile Branch had the highest concentrations observed in the Savannah River watershed, reaching 1,890 ng/l for total mercury and 34.0 ng/l for methylmercury. The second study developed a mercury bioaccumulation factor (BAF) for the Savannah River near SRS. A BAF is the ratio of the concentration of mercury in fish flesh to the concentration of mercury in the water. BAFs are important in the TMDL process because target concentrations for mercury in water are computed from BAFs. Mercury BAFs are known to differ substantially among fish species, water bodies, and possibly seasons. Knowledge of such variation is needed to determine a BAF that accurately represents average and extreme conditions in the water body under study. Analysis of fish tissue and aqueous methylmercury samples collected at a number of locations and over several seasons in a 110 km (68 mile) reach of the Savannah River demonstrated that BAFs for each species under study varied by factors of three to eight. Influences on BAF variability were location, habitat and season-related differences in fish mercury levels and seasonal differences in methylmercury levels in the water. Overall (all locations, habitats, and seasons) average BAFs were 3.7 x 10{sup 6} for largemouth bass, 1.4 x 10{sup 6} for sunfishes, and 2.5 x 10{sup 6} for white catfish. This study

Mercury CEM Calibration

Energy Technology Data Exchange (ETDEWEB)

John F. Schabron; Joseph F. Rovani; Susan S. Sorini

2007-03-31

The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

Mercury Exposure and Heart Diseases

Science.gov (United States)

Genchi, Giuseppe; Sinicropi, Maria Stefania; Carocci, Alessia; Lauria, Graziantonio; Catalano, Alessia

2017-01-01

Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system. PMID:28085104

Mercury Exposure and Heart Diseases.

Science.gov (United States)

Genchi, Giuseppe; Sinicropi, Maria Stefania; Carocci, Alessia; Lauria, Graziantonio; Catalano, Alessia

2017-01-12

Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

Mercury Exposure and Heart Diseases

Directory of Open Access Journals (Sweden)

Giuseppe Genchi

2017-01-01

Full Text Available Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

Mercury removal from liquid and solid mixed waste

International Nuclear Information System (INIS)

Gates, D.D.; Klasson, K.T.; Corder, S.L.; Cameron, P.A.; Perona, J.J.

1995-01-01

Based on bench-scale laboratory experiments, the following conclusions were reached: Sulfur-impregnated, activated, carbon pellets (Mersorb) can be used to remove mercury (Hg 2+ ) to below EPA's toxic characteristic level (0.2 mg/L). Mersorb works under acid conditions (pH 2) but its capacity is reduced by approximately 50% compared with neutral conditions. Competing ions present in the target waste stream reduced the Mersorb capacity by 50%. Mersorb appears to be economical compared with leading ion exchange resin. KI/I 2 leaching solution can be used to remove up to 99% of Hg in contaminated soil and glass. KI/I 2 leaching solution worked well with several mercury species, including Hg 0 , HgO, HgS, and HgCl 2 . KI/I 2 leaching solution worked well with a wide variety of initial mercury concentrations. Radionuclide surrogate studies suggested that uranium will not partition into KI/I 2 leaching solutions. Cesium may partition into the KI/I 2 leaching solution because of the high solubility of cesium salts

Sexual differences in the excretion of organic and inorganic mercury by methyl mercury-treated rats

International Nuclear Information System (INIS)

Thomas, D.J.; Fisher, H.L.; Sumler, M.R.; Mushak, P.; Hall, L.L.

1987-01-01

Adult male and female Long Evans rats received 1 mumole of methyl ( 203 Hg) mercuric chloride per kilogram sc. Whole-body retention of mercury and excretion of organic and inorganic mercury in urine and feces were monitored for 98 days after dosing. Females cleared mercury from the body more rapidly than did males. The major route of mercury excretion was feces. By 98 days after dosing, cumulative mercury excretion in feces accounted for about 51% of the dose in males and about 54% of the dose in females. For both sexes, about 33% of the dose was excreted in feces as inorganic mercury. Cumulative excretion of organic mercury in feces accounted for about 18 and 21% of the dose in males and females, respectively. Urinary excretion of mercury was quantitatively a smaller route for mercury clearance but important sexual differences in loss by this route were found. Over the 98-day experimental period, males excreted in urine about 3.2% of the dose and females excreted 7.5%. Cumulative organic Hg excretion in urine accounted for 1.8% of the dose in males and 5.3% of the dose in females. These sexual differences in urinary and fecal excretion of organic and inorganic mercury following methyl mercury treatment were consistent with previous reports of sexual differences in mercury distribution and retention in methyl mercury-treated rats, particularly sexual differences in organic mercury uptake and retention in the kidney. Relationships between body burdens of organic or inorganic Hg and output of these forms of Hg in urine and feces were also found to be influenced by the interval after MeHg treatment and by sex. Relationship between concentration of Hg in liver and feces and in kidney and urine differed for organic and inorganic Hg and depended upon sexual status and interval after MeHg treatment

Status of the Spallation Neutron Source with focus on target materials

International Nuclear Information System (INIS)

Mansur, L.K.; Haines, J.R.

2006-01-01

An overview of the design and construction of the Spallation Neutron Source (SNS) is presented. Key facility performance parameters are summarized and plans for initial operation are described. Early efforts produced a conceptual design in 1997; the project itself was initiated in 1999, with the official groundbreaking taking place in December of 1999. As of April 2005 building construction was complete and the overall project was more than 90% complete. The design of the target and surrounds are finished and the first target was installed in June 2005. First beam on target is expected in June, 2006. The engineering design of the target region is described. The key systems comprise the mercury target, moderator and reflector assemblies, remote handling systems, utilities and shielding. Through interactions with the 1 GeV proton beam, the target, moderators and reflectors produce short pulse neutrons in thermal energy ranges, which are transported to a variety of neutron scattering instruments. The mercury target module itself is described in more detail. Materials issues are expected to govern the overall lifetime and have influenced the design, fabrication and planned operation. A wide range of materials research and development has been carried out to provide experimental data and analyses to ensure the satisfactory performance of the target and to set initial design conditions. Materials R and D concentrated mainly on cavitation erosion, radiation effects, and mercury compatibility issues, including investigations of the mechanical properties during exposure to mercury. Questions that would require future materials research are discussed

Radioimmunoassay of CA 19-9 tumor marker in the diagnosis of thyroid cancer

International Nuclear Information System (INIS)

Markov, V.V.; Slavnov, V.N.; Komissarenko, I.V.; Kovpak, N.A.; Kovalenko, A.E.; Guda, B.B.

1999-01-01

Applicability of determining carbohydrate antigen CA 19-9 content in blood serum, tissue extracts, and thyroid tumor aspiration biopsy samples to the differential diagnosis of benign and malignant tumors of thyroid is studied. Radioimmunoassay was used for measurements. It is shown that determination of marker CA 19-9 in blood serum is not informationally capable for the differential diagnosis of thyroid tumors. Considerable increase in CA 19-9 concentration was found in tumor aspiration biopsy samples from patients with malignant tumors this fact can be used for preoperative diagnosis of thyroid cancer [ru

Mercury dynamics in a coastal aquifer: Maunalua Bay, O´ahu, Hawai´i

Science.gov (United States)

Ganguli, Priya M.; Swarzenski, Peter W.; Dulaiova, Henrieta; Glenn, Craig R.; Flegal, A. Russell

2014-03-01

We evaluated the influence of groundwater-seawater interaction on mercury dynamics in Maunalua Bay, a coral reef ecosystem located on the south shore of O´ahu, Hawai´i, by combining geochemical data with submarine groundwater discharge (SGD) rates. During a rising tide, unfiltered total mercury (U-HgT) concentrations in seawater increased from ˜6 to 20 pM at Black Point (west Bay) and from ˜2.5 to 8 pM at Niu (central Bay). We attribute this change to an increase in suspended particulate matter at high tide. Approximately 90% of mercury in groundwater at Niu was in the filtered (weighted average Maunalua Bay groundwater mercury flux of 0.68 ± 0.67 mol yr-1 by combining the proportional flux of F-HgT from three distinct SGD zones, and place these results into a broader context by comparing and contrasting flux estimates from locations around the world. Results from existing SGD studies should be evaluated to develop future sampling strategies that address more targeted questions about mercury biogeochemical cycling at the groundwater-seawater interface.

76 FR 13851 - National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell...

Science.gov (United States)

2011-03-14

... National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali...-5] RIN 2060-AN99 National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants AGENCY: Environmental Protection Agency (EPA). ACTION: Supplemental...

Mercury in Nordic ecosystems

Energy Technology Data Exchange (ETDEWEB)

Munthe, John; Waengberg, Ingvar (IVL Swedish Environmental Research Inst., Stockholm (SE)); Rognerud, Sigurd; Fjeld, Eirik (Norwegian Inst. for Water Research (NIVA), Oslo (Norway)); Verta, Matti; Porvari, Petri (Finnish Environment Inst. (SYKE), Helsinki (Finland)); Meili, Markus (Inst. of Applied Environmental Research (ITM), Stockholm (Sweden))

2007-12-15

This report provides a first comprehensive compilation and assessment of available data on mercury in air, precipitation, sediments and fish in the Nordic countries. The main conclusion is that mercury levels in Nordic ecosystems continue to be affected by long-range atmospheric transport. The geographical patterns of mercury concentrations in both sediments and fish are also strongly affected by ecosystem characteristics and in some regions possibly by historical pollution. An evaluation of geographical variations in mercury concentrations in precipitation indicates that the influence from anthropogenic sources from Central European areas is still significant. The annual variability of deposition is large and dependant of precipitation amounts. An evaluation of data from stations around the North Sea has indicated a significant decrease in mercury concentrations in precipitation indicating a continuous decrease of emissions in Europe (Waengberg et al., 2007). For mercury in air (TGM), the geographical pattern is less pronounced indicating the influence of mercury emissions and distribution over a larger geographical area (i.e. hemispherical transport). Comparison of recent (surficial) and historical lake sediments show significantly elevated concentrations of mercury most likely caused by anthropogenic atmospheric deposition over the past century. The highest pollution impact was observed in the coastal areas of southern Norway, in south western Finland and in Sweden from the coastal areas in the southwest across the central parts to the north-east. The general increase in recent versus old sediments was 2-5 fold. Data on mercury in Nordic freshwater fish was assembled and evaluated with respect to geographical variations. The fish data were further compared with temporal and spatial trends in mercury deposition and mercury contamination of lake sediments in order to investigate the coupling between atmospheric transport and deposition of mercury and local mercury

Sub-mm Scale Fiber Guided Deep/Vacuum Ultra-Violet Optical Source for Trapped Mercury Ion Clocks

Science.gov (United States)

Yi, Lin; Burt, Eric A.; Huang, Shouhua; Tjoelker, Robert L.

2013-01-01

We demonstrate the functionality of a mercury capillary lamp with a diameter in the sub-mm range and deep ultraviolet (DUV)/ vacuum ultraviolet (VUV) radiation delivery via an optical fiber integrated with the capillary. DUV spectrum control is observed by varying the fabrication parameters such as buffer gas type and pressure, capillary diameter, electrical resonator design, and temperature. We also show spectroscopic data of the 199Hg+ hyper-fine transition at 40.5GHz when applying the above fiber optical design. We present efforts toward micro-plasma generation in hollow-core photonic crystal fiber with related optical design and theoretical estimations. This new approach towards a more practical DUV optical interface could benefit trapped ion clock developments for future ultra-stable frequency reference and time-keeping applications.

Understanding the mercury reduction issue: the impact of mercury on the environment and human health.

Science.gov (United States)

Kao, Richard T; Dault, Scott; Pichay, Teresa

2004-07-01

Mercury has been used in both medicine and dentistry for centuries. Recent media attention regarding the increased levels of mercury in dietary fish, high levels of mercury in air emissions, and conjecture that certain diseases may be caused by mercury exposure has increased public awareness of the potential adverse health effects of high doses of mercury. Dentistry has been criticized for its continued use of mercury in dental amalgam for both public health and environmental reasons. To address these concerns, dental professionals should understand the impact of the various levels and types of mercury on the environment and human health. Mercury is unique in its ability to form amalgams with other metals. Dental amalgam--consisting of silver, copper, tin, and mercury--has been used as a safe, stable, and cost-effective restorative material for more than 150 years. As a result of this use, the dental profession has been confronted by the public on two separate health issues concerning the mercury content in amalgam. The first issue is whether the mercury amalgamated with the various metals to create dental restorations poses a health issue for patients. The second is whether the scraps associated with amalgam placement and the removal of amalgam restorations poses environmental hazards which may eventually have an impact on human health. Despite the lack of scientific evidence for such hazards, there is growing pressure for the dental profession to address these health issues. In this article, the toxicology of mercury will be reviewed and the impact of amalgam on health and the environment will be examined.

Monsoon-facilitated characteristics and transport of atmospheric mercury at a high-altitude background site in southwestern China

Directory of Open Access Journals (Sweden)

H. Zhang

2016-10-01

Full Text Available To better understand the influence of monsoonal climate and transport of atmospheric mercury (Hg in southwestern China, measurements of total gaseous mercury (TGM, defined as the sum of gaseous elemental mercury, GEM, and gaseous oxidized mercury, GOM, particulate bound mercury (PBM and GOM were carried out at Ailaoshan Station (ALS, 2450 m a.s.l. in southwestern China from May 2011 to May 2012. The mean concentrations (± SD for TGM, GOM and PBM were 2.09 ± 0.63, 2.2 ± 2.3 and 31.3 ± 28.4 pg m−3, respectively. TGM showed a monsoonal distribution pattern with relatively higher concentrations (2.22 ± 0.58 ng m−3, p  =  0.021 during the Indian summer monsoon (ISM, from May to September and the east Asia summer monsoon (EASM, from May to September periods than that (1.99 ± 0.66 ng m−3 in the non-ISM period. Similarly, GOM and PBM concentrations were higher during the ISM period than during the non-ISM period. This study suggests that the ISM and the EASM have a strong impact on long-range and transboundary transport of Hg between southwestern China and south and southeast Asia. Several high TGM events were accompanied by the occurrence of northern wind during the ISM period, indicating anthropogenic Hg emissions from inland China could rapidly increase TGM levels at ALS due to strengthening of the EASM. Most of the TGM and PBM events occurred at ALS during the non-ISM period. Meanwhile, high CO concentrations were also observed at ALS, indicating that a strong south tributary of westerlies could have transported Hg from south and southeast Asia to southwestern China during the non-ISM period. The biomass burning in southeast Asia and anthropogenic Hg emissions from south Asia are thought to be the source of atmospheric Hg in remote areas of southwestern China during the non-ISM period.

Mercury and selenium in European catfish (Silurus glanis) from Northern Italian Rivers: can molar ratio be a predictive factor for mercury toxicity in a top predator?

Science.gov (United States)

Squadrone, S; Benedetto, A; Brizio, P; Prearo, M; Abete, M C

2015-01-01

The study of mercury and selenium bioaccumulation in fish is crucially important for evaluating the extent of contamination in freshwater environments, and the possible health risk posed for humans when the antagonistic interactions of these two elements are considered. Several factors affect the risk of mercury intake from fish consumption, including mercury levels, human consumption patterns, and sensitive populations (e.g., pregnant women, foetuses, young children and unknown genetic factors). The protective effects of selenium on mercury toxicity have been extensively publicised in recent years, particularly targeting fish consumers. In this study, mercury (Hg) and selenium (Se) concentrations were determined in the muscle of European catfish (Silurus glanis) collected from North Italian Rivers. Differences in mercury and selenium levels, as a function of size, gender and location were investigated. Hg was strongly related to length, gender and location, while Se levels are not dependent on fish size or location. The mean Se/Hg molar ratio was strongly affected by location, and significantly related to length and age. Selenium was in molar excess of mercury in all sites, with a rank order of mean Se/Hg molar ratio of the Parma River (2.55)>Po River (1.71)>Tanaro River (1.66)>Bormida River (1.36). However, in 37% of analyzed samples, Hg exceeded the maximum level set by 1881/2006/EC and 629/2008/EC in fish muscle. The molar ratio of Se/Hg was 0.5mg/kg), and therefore the mean molar ratio cannot be considered as a safety criterion in top predator fish. Copyright © 2014 Elsevier Ltd. All rights reserved.

Getting Mercury out of Schools.

Science.gov (United States)

1999

This guide was prepared while working with many Massachusetts schools to remove items that contain mercury and to find suitable alternatives. It contains fact sheets on: mercury in science laboratories and classrooms, mercury in school buildings and maintenance areas, mercury in the medical office and in medical technology classrooms in vocational…

Mercury Stable Isotopes Discriminate Different Populations of European Seabass and Trace Potential Hg Sources around Europe.

Science.gov (United States)

Cransveld, Alice; Amouroux, David; Tessier, Emmanuel; Koutrakis, Emmanuil; Ozturk, Ayaka A; Bettoso, Nicola; Mieiro, Cláudia L; Bérail, Sylvain; Barre, Julien P G; Sturaro, Nicolas; Schnitzler, Joseph; Das, Krishna

2017-11-07

Our study reports the first data on mercury (Hg) isotope composition in marine European fish, for seven distinct populations of the European seabass, Dicentrarchus labrax. The use of δ 202 Hg and Δ 199 Hg values in SIBER enabled us to estimate Hg isotopic niches, successfully discriminating several populations. Recursive-partitioning analyses demonstrated the relevance of Hg stable isotopes as discriminating tools. Hg isotopic values also provided insight on Hg contamination sources for biota in coastal environment. The overall narrow range of δ 202 Hg around Europe was suggested to be related to a global atmospheric contamination while δ 202 Hg at some sites was linked either to background contamination, or with local contamination sources. Δ 199 Hg was related to Hg levels of fish but we also suggest a relation with ecological conditions. Throughout this study, results from the Black Sea population stood out, displaying a Hg cycling similar to fresh water lakes. Our findings bring out the possibility to use Hg isotopes in order to discriminate distinct populations, to explore the Hg cycle on a large scale (Europe) and to distinguish sites contaminated by global versus local Hg source. The interest of using Hg sable isotopes to investigate the whole European Hg cycle is clearly highlighted.

Mercury Specie and Multi-Pollutant Control

Energy Technology Data Exchange (ETDEWEB)

Rob James; Virgil Joffrion; John McDermott; Steve Piche

2010-05-31

This project was awarded to demonstrate the ability to affect and optimize mercury speciation and multi-pollutant control using non-intrusive advanced sensor and optimization technologies. The intent was to demonstrate plant-wide optimization systems on a large coal fired steam electric power plant in order to minimize emissions, including mercury (Hg), while maximizing efficiency and maintaining saleable byproducts. Advanced solutions utilizing state-of-the-art sensors and neural network-based optimization and control technologies were proposed to maximize the removal of mercury vapor from the boiler flue gas thereby resulting in lower uncontrolled releases of mercury into the atmosphere. Budget Period 1 (Phase I) - Included the installation of sensors, software system design and establishment of the as-found baseline operating metrics for pre-project and post-project data comparison. Budget Period 2 (Phase II) - Software was installed, data communications links from the sensors were verified, and modifications required to integrate the software system to the DCS were performed. Budget Period 3 (Phase III) - Included the validation and demonstration of all control systems and software, and the comparison of the optimized test results with the targets established for the project site. This report represents the final technical report for the project, covering the entire award period and representing the final results compared to project goals. NeuCo shouldered 61% of the total project cost; while DOE shouldered the remaining 39%. The DOE requires repayment of its investment. This repayment will result from commercial sales of the products developed under the project. NRG's Limestone power plant (formerly owned by Texas Genco) contributed the host site, human resources, and engineering support to ensure the project's success.

Environmental Mercury and Its Toxic Effects

Directory of Open Access Journals (Sweden)

Kevin M. Rice

2014-03-01

Full Text Available Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiology of individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

Histochemical demonstration of two mercury pools in trout tissues: mercury in kidney and liver after mercuric chloride exposure

International Nuclear Information System (INIS)

Baatrup, E.; Nielsen, M.G.; Danscher, G.

1986-01-01

Juvenile rainbow trout (Salmo gairdneri) were exposed to 100 ppb mercury (as HgCl 2 ) in the water for 14 days. Concentrations of mercury in water and fish organs were monitored using radiolabeled mercury. Tissues from kidney and liver were fixed, and sections were developed by autometallography, a method whereby accumulations of mercury sulfides and/or mercury selenides are silver amplified. In the kidney, mercury was found within lysosomes and extracellularly in the basal lamina of proximal tubules. In the liver, mercury was found within lysosomes of the hepatocytes. Additional groups of mercury-exposed trout were subjected to selenium (as Na 2 SeO 3 ), administered intraperitoneally 2 hr before fixation. Following this treatment, additional mercury could be visualized in the kidney circulatory system, including glomeruli, and in the nucleus and endoplasmic reticulum of liver cells. It is suggested that the mercury visualized prior to selenium treatment represents inorganic mercury, while additional mercury visualized after selenium administration represents an organic form

Present status of spallation target development. JAERI/KEK Joint Project

International Nuclear Information System (INIS)

Hino, R.; Kaminaga, M.; Haga, K.

2001-01-01

The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a plan to construct a neutron scattering facility under the JAERI/KEK Joint Project. Design and R and D works are being carried out vigorously for realizing the mercury target system consisting of the mercury target, moderators and reflectors working as a spallation neutron source, as well as a remote handling system for exchanging such components which will be highly irradiated. This report introduces an outline of the present status of design and development activities on the spallation target system. (author)

Distribution of mercury in guinea pig offspring after in utero exposure to mercury vapor during late gestation

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Minoru; Yamamura, Yukio; Sataoh, Hiroshi

1986-04-01

Organ distribution of mercury after in utero mercury vapor exposure was investigated in neonatal guinea pigs. Mother guinea pigs in late gestation were exposed to 0.2-0.3 mg/m/sup 3/ mercury vapor 2 h per day until giving birth. Mercury concentrations in neonatal brain, lungs, heart, kidneys, plasma and erythrocytes were much lower than those of maternal organs and tissues. Neonatal liver, however, showed a mercury concentration twice as high as maternal liver. Mercury concentration ratios of erythrocytes to plasma in offspring were quite different from those of mothers, being 0.2-0.4 for offspring, and 1.3-3.0 for mothers. These results suggested that mercury vapor metabolism in fetuses was quite different from that in their mothers. This may be due to the different blood circulation, as mercury vapor transferred through the placental barrier would be rapidly oxidized into ionic mercury in fetal liver and accumulated in the organ. The different mercury vapor metabolism may prevent fetal brain, which is rapidly developing, and thus vulnerable, from being exposed to excessive mercury vapor.

Radiation induced cavitation: A possible phenomenon in liquid targets?

Energy Technology Data Exchange (ETDEWEB)

West, C.D.

1998-07-01

The proposed design of a new, short-pulse spallation neutron source includes a liquid mercury target irradiated with a 1 GeV proton beam. This paper explores the possibility that cavitation bubbles may be formed in the mercury and briefly discusses some design features that could avoid harmful effects should cavitation take place.

Radiation induced cavitation: A possible phenomenon in liquid targets?

International Nuclear Information System (INIS)

West, C.D.

1998-01-01

The proposed design of a new, short-pulse spallation neutron source includes a liquid mercury target irradiated with a 1 GeV proton beam. This paper explores the possibility that cavitation bubbles may be formed in the mercury and briefly discusses some design features that could avoid harmful effects should cavitation take place

Factors Affecting Mercury Stable Isotopic Distribution in Piscivorous Fish of the Laurentian Great Lakes.

Science.gov (United States)

Lepak, Ryan F; Janssen, Sarah E; Yin, Runsheng; Krabbenhoft, David P; Ogorek, Jacob M; DeWild, John F; Tate, Michael T; Holsen, Thomas M; Hurley, James P

2018-03-06

Identifying the sources of methylmercury (MeHg) and tracing the transformations of mercury (Hg) in the aquatic food web are important components of effective strategies for managing current and legacy Hg sources. In our previous work, we measured stable isotopes of Hg (δ 202 Hg, Δ 199 Hg, and Δ 200 Hg) in the Laurentian Great Lakes and estimated source contributions of Hg to bottom sediment. Here, we identify isotopically distinct Hg signatures for Great Lakes trout ( Salvelinus namaycush) and walleye ( Sander vitreus), driven by both food-web and water-quality characteristics. Fish contain high values for odd-isotope mass independent fractionation (MIF) with averages ranging from 2.50 (western Lake Erie) to 6.18‰ (Lake Superior) in Δ 199 Hg. The large range in odd-MIF reflects variability in the depth of the euphotic zone, where Hg is most likely incorporated into the food web. Even-isotope MIF (Δ 200 Hg), a potential tracer for Hg from precipitation, appears both disconnected from lake sedimentary sources and comparable in fish among the five lakes. We suggest that similar to the open ocean, water-column methylation also occurs in the Great Lakes, possibly transforming recently deposited atmospheric Hg deposition. We conclude that the degree of photochemical processing of Hg is controlled by phytoplankton uptake rather than by dissolved organic carbon quantity among lakes.

Mercury in mercury(II)-spiked soils is highly susceptible to plant bioaccumulation.

Science.gov (United States)

Hlodák, Michal; Urík, Martin; Matúš, Peter; Kořenková, Lucia

2016-01-01

Heavy metal phytotoxicity assessments usually use soluble metal compounds in spiked soils to evaluate metal bioaccumulation, growth inhibition and adverse effects on physiological parameters. However, exampling mercury phytotoxicity for barley (Hordeum vulgare) this paper highlights unsuitability of this experimental approach. Mercury(II) in spiked soils is extremely bioavailable, and there experimentally determined bioaccumulation is significantly higher compared to reported mercury bioaccumulation efficiency from soils collected from mercury-polluted areas. Our results indicate this is not affected by soil sorption capacity, thus soil ageing and formation of more stable mercuric complexes with soil fractions is necessary for reasonable metal phytotoxicity assessments.

Below a Historic Mercury Mine: Non-linear Patterns of Mercury Bioaccumulation in Aquatic Organisms

Science.gov (United States)

Haas, J.; Ichikawa, G.; Ode, P.; Salsbery, D.; Abel, J.

2001-12-01

Unlike most heavy metals, mercury is capable of bioaccumulating in aquatic food-chains, primarily because it is methylated by bacteria in sediment to the more toxic methylmercury form. Mercury concentrations in a number of riparian systems in California are highly elevated as a result of historic mining activities. These activities included both the mining of cinnabar in the coastal ranges to recover elemental mercury and the use of elemental mercury in the gold fields of the Sierra Nevada Mountains. The most productive mercury mining area was the New Almaden District, now a county park, located in the Guadalupe River drainage of Santa Clara County, where cinnabar was mined and retorted for over 100 years. As a consequence, riparian systems in several subwatersheds of the Guadalupe River drainage are contaminated with total mercury concentrations that exceed state hazardous waste criteria. Mercury concentrations in fish tissue frequently exceed human health guidelines. However, the potential ecological effects of these elevated mercury concentrations have not been thoroughly evaluated. One difficulty is in extrapolating sediment concentrations to fish tissue concentrations without accounting for physical and biological processes that determine bioaccumulation patterns. Many processes, such as methylation and demethylation of mercury by bacteria, assimilation efficiency in invertebrates, and metabolic rates in fish, are nonlinear, a factor that often confounds attempts to evaluate the effects of mercury contamination on aquatic food webs. Sediment, benthic macroinvertebrate, and fish tissue samples were collected in 1998 from the Guadalupe River drainage in Santa Clara County at 13 sites upstream and downstream from the historic mining district. Sediment and macroinvertebrate samples were analyzed for total mercury and methylmercury. Fish samples were analyzed for total mercury as whole bodies, composited by species and size. While linear correlations of sediment

Mercury pollution in Wuchuan mercury mining area, Guizhou, Southwestern China: the impacts from large scale and artisanal mercury mining.

Science.gov (United States)

Li, Ping; Feng, Xinbin; Qiu, Guangle; Shang, Lihai; Wang, Shaofeng

2012-07-01

To evaluate the environmental impacts from large scale mercury mining (LSMM) and artisanal mercury mining (AMM), total mercury (THg) and methyl mercury (MeHg) were determined in mine waste, ambient air, stream water and soil samples collected from Wuchuan mercury (Hg) mining area, Guizhou, Southwestern China. Mine wastes from both LSMM and AMM contained high THg concentrations, which are important Hg contamination sources to the local environment. Total gaseous mercury (TGM) concentrations in the ambient air near AMM furnaces were highly elevated, which indicated that AMM retorting is a major source of Hg emission. THg concentrations in the stream water varied from 43 to 2100 ng/L, where the elevated values were mainly found in the vicinity of AMM and mine waste heaps of LSMM. Surface soils were seriously contaminated with Hg, and land using types and organic matter played an important role in accumulation and transportation of Hg in soil. The results indicated heavy Hg contaminations in the study area, which were resulted from both LSMM and AMM. The areas impacted by LSMM were concentrated in the historical mining and smelting facilities, while Hg pollution resulted from AMM can be distributed anywhere in the Hg mining area. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comment: 199 [Taxonomy Icon

Lifescience Database Archive (English)

Full Text Available nal Institute for Basic Biology) licensed under CC Attribution2.1 Japan メダカ近交系 Hd-rR系統 南日本集団由来の純系。 メダカで最初にゲノム解読が行われた系統。 撮影:成瀬清（基礎生物学...研究所） Photo: Kiyoshi Naruse (National Institute for Basic Biology) bando 2009/09/30 11:23:24 2010/01/14 20:09:43 ... ...Japanese medaka Oryzias latipes Oryzias_latipes_L.png 199.png Kiyoshi Naruse (Natio

Behaviour of mercury compounds in soil

Energy Technology Data Exchange (ETDEWEB)

Booer, J R

1944-01-01

The uses of inorganic compounds of mercury for the control of plant pests is reviewed, and a summary of the relevant chemical and physical properties of the compounds concerned is given. On chemical evidence a working hypothesis is propounded showing that all compounds may be expected to decompose into metallic mercury. A pot technique is described by means of which a correlation can be obtained between the effective mercury content of a given soil sample and the rate of growth of wheat seedlings. The mathematical treatment of the results is described, and the validity of the pot technique is verified by statistical analysis of results. Using the pot technqiue it is shown that volatilization losses are insignificant but that mercury is slowly rendered ineffective by the formation of mercuric sulphide. The effect of sulphur-reducing bacteria is considered and the influence of Vibrio desulphuricans on mercury is studied in detail. Experimental evidence obtained by the pot technique is produced to show that mercurous chloride slowly decomposes in the soil giving mercury and mercuric chloride, mercuric chloride rapidly decomposes into mercury and mercurous chloride, and other inorganic compounds decompose directly into mercury. The working hypothesis is substantiated in all major aspects. The uses and properties of the organo-mercury compounds are then discussed. Type compounds selected are ethyl mercury phosphate, phenyl mercury acetate and methoxyethyl mercury acetate. Using the pot technique it is shown that the formation of organo-mercury clays takes place and that these clays decompose giving metallic mercury. A mechanism is suggested.

Mercury in the environment : a review

International Nuclear Information System (INIS)

Goodarzi, F.

2000-01-01

Both geogenic and anthropogenic sources are responsible for the input of mercury into the environment. However, mercury comes mostly from geogenic sources and is found naturally in air, water and soil. Crustal degassing results in emission of mercury into the atmosphere. Mercury in water and soil is due mostly to input from sedimentary rocks. Mercury in lake sediments is related mainly to input by country rock and anthropogenic activities such as agriculture. The mercury content of coal is similar to or less than the amount found in the earths crust. Natural charcoal is also able to capture mercury at low temperature combustion. The amount of mercury emitted from the stack of coal-fired power plants is related to the nature of the milled coal and its mineralogical and elemental content. Mercury emissions originating from the combustion of coal from electric utility power plants are considered to be among the greatest contributors to global mercury air emissions. In order to quantify the impact the electric power industry has on the environment, information regarding mercury concentrations in coal and their speciation is needed. For this reason the author examined the behaviour of mercury in three coal samples ashed at increasing temperatures. Mercury removal from coal-fired power plants ranges from 10 to 50 per cent by fabric filters and 20 to 95 per cent by FGD systems. This data will help in regulating emissions of hazardous air pollutants from electric utility steam generating units and will potentially provide insight into the industry's contribution to the global mercury burden. 50 refs

Axial mercury segregation in direct current operated low-pressure argon-mercury gas discharge: Part II. Model

International Nuclear Information System (INIS)

Gielen, John W A M; Groot, Simon de; Dijk, Jan van; Mullen, Joost J A M van der

2004-01-01

In a previous paper we had presented experimental results on mercury segregation due to cataphoresis in direct current operated low-pressure argon-mercury gas discharges. In this paper, we present our model to describe cataphoretic segregation in argon (or another noble gas)-mercury discharges. The model is based on the balance equations for mass and momentum and includes electrophoresis effects of electrons on mercury. Good agreement is found between the experimental results and model calculations. The model confirms our experimental observation that the mercury vapour pressure gradient depends on the local mercury vapour pressure. Furthermore, the model predicts the reversal of the direction of the transport of mercury under certain conditions (the phenomenon known as retrograde cataphoresis)

Mercury in Canadian crude oil

International Nuclear Information System (INIS)

Hollebone, B.P.

2005-01-01

Estimates for average mercury concentrations in crude oil range widely from 10 ng/g of oil to 3,500 ng/g of oil. With such a broad range of estimates, it is difficult to determine the contributions of the petroleum sector to the total budget of mercury emissions. In response to concerns that the combustion of petroleum products may be a major source of air-borne mercury pollution, Environment Canada and the Canadian Petroleum Products Institute has undertaken a survey of the average total mercury concentration in crude oil processed in Canadian refineries. In order to calculate the potential upper limit of total mercury in all refined products, samples of more than 30 different types of crude oil collected from refineries were measured for their concentration of mercury as it enters into a refinery before processing. High temperature combustion, cold vapour atomic absorption and cold vapour atomic fluorescence were the techniques used to quantify mercury in the samples. The results of the study provide information on the total mass of mercury present in crude oil processed in Canada each year. Results can be used to determine the impact of vehicle exhaust emissions to the overall Canadian mercury emission budget. 17 refs., 2 tabs., 2 figs

MESSENGER: Exploring Mercury's Magnetosphere

Science.gov (United States)

Slavin, James A.

2008-01-01

The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. Mercury's magnetosphere is unique in many respects. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. For this reason there are no closed dri-fi paths for energetic particles and, hence, no radiation belts; the characteristic time scales for wave propagation and convective transport are short possibly coupling kinetic and fluid modes; magnetic reconnection at the dayside magnetopause may erode the subsolar magnetosphere allowing solar wind ions to directly impact the dayside regolith; inductive currents in Mercury's interior should act to modify the solar In addition, Mercury's magnetosphere is the only one with its defining magnetic flux tubes rooted in a planetary regolith as opposed to an atmosphere with a conductive ionosphere. This lack of an ionosphere is thought to be the underlying reason for the brevity of the very intense, but short lived, approx. 1-2 min, substorm-like energetic particle events observed by Mariner 10 in Mercury's magnetic tail. In this seminar, we review what we think we know about Mercury's magnetosphere and describe the MESSENGER science team's strategy for obtaining answers to the outstanding science questions surrounding the interaction of the solar wind with Mercury and its small, but dynamic magnetosphere.

46 CFR 199.203 - Marshalling of liferafts.

Science.gov (United States)

2010-10-01

... LIFESAVING SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Passenger Vessels § 199.203 Marshalling of liferafts. (a) Each passenger vessel must have a lifeboat or rescue boat for each six liferafts when— (1) Each lifeboat and rescue boat is loaded with its full complement of persons; and (2) The...

The Mercury Laser Advances Laser Technology for Power Generation

Energy Technology Data Exchange (ETDEWEB)

Ebbers, C A; Caird, J; Moses, E

2009-01-21

The National Ignition Facility (NIF) at Lawrence Livermore Laboratory is on target to demonstrate 'breakeven' - creating as much fusion-energy output as laser-energy input. NIF will compress a tiny sphere of hydrogen isotopes with 1.8 MJ of laser light in a 20-ns pulse, packing the isotopes so tightly that they fuse together, producing helium nuclei and releasing energy in the form of energetic particles. The achievement of breakeven will culminate an enormous effort by thousands of scientists and engineers, not only at Livermore but around the world, during the past several decades. But what about the day after NIF achieves breakeven? NIF is a world-class engineering research facility, but if laser fusion is ever to generate power for civilian consumption, the laser will have to deliver pulses nearly 100,000 times faster than NIF - a rate of perhaps 10 shots per second as opposed to NIF's several shots a day. The Mercury laser (named after the Roman messenger god) is intended to lead the way to a 10-shots-per-second, electrically-efficient, driver laser for commercial laser fusion. While the Mercury laser will generate only a small fraction of the peak power of NIF (1/30,000), Mercury operates at higher average power. The design of Mercury takes full advantage of the technology advances manifest in its behemoth cousin (Table 1). One significant difference is that, unlike the flashlamp-pumped NIF, Mercury is pumped by highly efficient laser diodes. Mercury is a prototype laser capable of scaling in aperture and energy to a NIF-like beamline, with greater electrical efficiency, while still running at a repetition rate 100,000 times greater.

Mercury concentrations, speciation, and isotopic composition in sediment from a cold seep in the northern Gulf of Mexico

International Nuclear Information System (INIS)

Brown, Garry; Sleeper, Kenneth; Johnson, Marcus W.; Blum, Joel D.; Cizdziel, James V.

2013-01-01

Highlights: • T-Hg, MMHg, and Hg isotopes were determined in Gulf of Mexico deep marine sediments. • Levels of mass independent fractionation of Hg isotopes varied from coastal sediments. • Levels of the MMHg were only slightly elevated at the cold seep site. • Cold seeps do not appear to be significant sources of MMHg to Gulf of Mexico waters. -- Abstract: Total-Hg, monomethylmercury (MMHg), and mercury isotopic composition was determined in sediment from a cold seep and background sites in the northern Gulf of Mexico (nGoM). Total-Hg averaged 50 ng/g (n = 28), ranged from 31 to 67 ng/g, and decreased with depth (0–15 cm). MMHg averaged 0.91 ng/g (n = 18), and ranged from 0.2 to 1.9 ng/g. There was no significant difference for total-Hg or MMHg between cold seep and background sites. δ 202 Hg ranged from −0.5 to −0.8‰ and becomes more negative with depth (r = 0.989). Mass independent fractionation (Δ 199 Hg) was small but consistently positive (0.04–0.12‰); there was no difference between cold seeps (Δ 199 Hg = +0.09 ± 0.03; n = 7, 1SD) and background sites (Δ 199 Hg = +0.07 ± 0.02; n = 5, 1SD). This suggests that releases of hydrocarbons at the cold seep do not significantly alter Hg levels, and that cold seeps are likely not major sources of MMHg to nGoM waters

Mercury's Dynamic Magnetic Tail

Science.gov (United States)

Slavin, James A.

2010-01-01

The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The source of the great dynamic variability observed during these brief passages is due to Mercury's proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet's lack of an ionosphere and its small physical dimensions also contribute to Mercury's very brief Dungey cycle, approx. 2 min, which governs the time scale for internal plasma circulation. Current observations and understanding of the structure and dynamics of Mercury's magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury's tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

Mercury in Your Environment

Science.gov (United States)

Basic information about mercury, how it gets in the air, how people are exposed to it and health effects associated with exposure; what EPA and other organizations are doing to limit exposures; what citizens should know to minimize exposures and to reduce mercury in the environment; and information about products that contain mercury.

Decommissioning and safety issues of liquid-mercury waste generated from high power spallation sources with particle accelerators

CERN Document Server

Chiriki, S; Odoj, R; Moormann, R; Hinssen, H. K; Bukaemskiy, A

2009-01-01

Large spallation sources are intended to be constructed in Europe (EURISOL nuclear physics facility and ESS-European Spallation Source). These facilities accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Because solids are the only appropriate (immobile) form for this radiotoxic and toxic type of waste solidification is required for irradiated mercury. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in assumed accidents with water ingress in a repository compared to amalgams. For preparation of mercury sulfide a wet process is more suitable than a dry one. It is easier to perform under hot cell conditions and allows complete Hg-conversion. Embedding HgS in a cementitious matrix increases its stability.

Rapid Monitoring of Mercury in Air from an Organic Chemical Factory in China Using a Portable Mercury Analyzer

Directory of Open Access Journals (Sweden)

Akira Yasutake

2011-01-01

Full Text Available A chemical factory, using a production technology of acetaldehyde with mercury catalysis, was located southeast of Qingzhen City in Guizhou Province, China. Previous research showed heavy mercury pollution through an extensive downstream area. A current investigation of the mercury distribution in ambient air, soils, and plants suggests that mobile mercury species in soils created elevated mercury concentrations in ambient air and vegetation. Mercury concentrations of up to 600 ng/m3 in air over the contaminated area provided evidence of the mercury transformation to volatile Hg(0. Mercury analysis of soil and plant samples demonstrated that the mercury concentrations in soil with vaporized and plant-absorbable forms were higher in the southern area, which was closer to the factory. Our results suggest that air monitoring using a portable mercury analyzer can be a convenient and useful method for the rapid detection and mapping of mercury pollution in advanced field surveys.

Aerobic Mercury-resistant bacteria alter Mercury speciation and retention in the Tagus Estuary (Portugal).

Science.gov (United States)

Figueiredo, Neusa L; Canário, João; O'Driscoll, Nelson J; Duarte, Aida; Carvalho, Cristina

2016-02-01

Aerobic mercury-resistant bacteria were isolated from the sediments of two highly mercury-polluted areas of the Tagus Estuary (Barreiro and Cala do Norte) and one natural reserve area (Alcochete) in order to test their capacity to transform mercury. Bacterial species were identified using 16S rRNA amplification and sequencing techniques and the results indicate the prevalence of Bacillus sp. Resistance patterns to mercurial compounds were established by the determination of minimal inhibitory concentrations. Representative Hg-resistant bacteria were further tested for transformation pathways (reduction, volatilization and methylation) in cultures containing mercury chloride. Bacterial Hg-methylation was carried out by Vibrio fluvialis, Bacillus megaterium and Serratia marcescens that transformed 2-8% of total mercury into methylmercury in 48h. In addition, most of the HgR bacterial isolates showed Hg(2+)-reduction andHg(0)-volatilization resulting 6-50% mercury loss from the culture media. In summary, the results obtained under controlled laboratory conditions indicate that aerobic Hg-resistant bacteria from the Tagus Estuary significantly affect both the methylation and reduction of mercury and may have a dual face by providing a pathway for pollution dispersion while forming methylmercury, which is highly toxic for living organisms. Copyright © 2015 Elsevier Inc. All rights reserved.

EDITORIAL: Mercury-free discharges for lighting

Science.gov (United States)

Haverlag, M.

2007-07-01

This special Cluster of articles in Journal of Physics D: Applied Physics covers the subject of mercury-free discharges that are being investigated by different light source researchers, as an alternative to existing mercury-containing lamps. The main driving force to move away from mercury-containing discharge light sources is connected to the environmentally unfriendly nature of mercury. After inhalation or direct contact, severe mercury exposure can lead to damage to human brain cells, the kidneys, the liver and the nervous system. For this reason, the use of mercury in products is becoming more and more restricted by different governmental bodies. In the lighting industry, however, many products still make use of mercury, for different reasons. The main reason is that mercury-containing products are, in most cases, more efficient than mercury-free products. For a realistic comparison of the environmental impact, the mercury-contamination due to electricity production must be taken into account, which depends on the type of fuel being used. For an average European fuel-mix, the amount of mercury that is released into the environment is around 29 μg kWh-1. This means that a typical 30 W TL lamp during a lifetime of 20,000 hours will release a total of about 20 mg mercury due to electricity production, which exceeds the total mercury dose in the lamp (more and more of which is being recycled) by a factor of 5-10 for a modern TL lamp. This illustrates that, quite apart from other environmental arguments like increased CO2 production, mercury-free alternatives that use more energy can in fact be detrimental for the total mercury pollution over the lifetime of the lamp. For this reason, the lighting industry has concentrated on lowering the mercury content in lamps as long as no efficient alternatives exist. Nevertheless, new initiatives for HID lamps and fluorescent lamps with more or less equal efficiency are underway, and a number of them are described in this

MicroRNA-199a-5p Regulates the Proliferation of Pulmonary Microvascular Endothelial Cells in Hepatopulmonary Syndrome

Directory of Open Access Journals (Sweden)

Jing Zeng

2015-10-01

Full Text Available Background/Aims: Pulmonary microvascular endothelial cell (PMVEC proliferation and angiogenesis contribute to the development of hepatopulmonary syndrome (HPS. MicroRNA-199a-5p (miR-199a-5p has emerged as a potent regulator of angiogenesis, and its expression levels significantly decrease in the serum of patients with hepatopathy. However, it has not been reported about whether miR-199a-5p might control PMVEC proliferation. Here, we described the miR-199a-5p governing PMVEC proliferation in HPS. Methods: PMVECs were treated with rat serum from common bile duct ligation (CBDL or sham. MiR-199a-5p mimic or inhibitor was used to change the miR-199a-5p expression. Knockdown of caveolin-1 (Cav-1 was performed using siRNA. NSC-23766 was used to inhibit Rac1 activity. Gene and protein expressions were quantified by qRT-PCR and western blot. Cell proliferation was analyzed by 3H-TdR incorporation and CCK-8 assays. Stress fibers were detected by immunofluorescence. Results: CBDL rat serum induced the down-regulation of miR-199a-5p. Delivery of miR-199a-5p suppressed the CBDL rat serum-induced PMVEC proliferation whereas knockdown of miR-199a-5p promoted PMVEC proliferation. This was accompanied by a decrease and an increase in Cav-1 expression, respectively. Cav-1 siRNA abolished the enhancement of PMVEC proliferation induced by the miR-199a-5p inhibition. Although stress fibers were disrupted in Cav-1 deficient cells, NSC-23766 increased stress fibers and contributed to cell proliferation. Conclusions: CBDL rat serum induced down-regulation of miR-199a-5p in PMVECs, which led to an increase of Cav-1 gene expression. Increased Cav-1 expression, by inhibiting Rac1 activity, led to the formation of stress fibers, which contribute to PMVEC proliferation and thus the pathogenesis of HPS.

Intoxication with metallic mercury

International Nuclear Information System (INIS)

Fichte, B.; Assmann, H.; Ritzau, F.

1984-01-01

Intoxications by metallic mercury are extremely rare. Report of a patient, who tried to commit suicide by subcutaneous injection of 500 g of metallic mercury. He died 16 months later in the course of the intoxication. A short review is given of effects and reactions of metallic mercury in the human organism. (orig.) [de

Intoxication with metallic mercury

Energy Technology Data Exchange (ETDEWEB)

Fichte, B.; Ritzau, F.; Assmann, H.

1984-02-01

Intoxications by metallic mercury are extremely rare. Report is given of a patient who tried to commit suicide by subcutaneous injection of 500 g of metallic mercury. He died 16 months later in the course of the intoxication. A short review is given of effects and reactions of metallic mercury in the human organism.

Intoxication with metallic mercury

Energy Technology Data Exchange (ETDEWEB)

Fichte, B.; Assmann, H.; Ritzau, F.

1984-02-01

Intoxications by metallic mercury are extremely rare. Report is given of a patient, who tried to commit suicide by subcutaneous injection of 500 g of metallic mercury. He died 16 months later in the course of the intoxication. A short review is given of effects and reactions of metallic mercury in the human organism.

Mercury in dated Greenland marine sediments

DEFF Research Database (Denmark)

Asmund, G.; Nielsen, S.P.

2000-01-01

Twenty marine sediment cores from Greenland were analysed for mercury, and dated by the lead-210 method. In general the cores exhibit a mercury profile with higher mercury concentrations in the upper centimetres of the core. The cores were studied by linear regression of In Hg vs, age of the sedi......Twenty marine sediment cores from Greenland were analysed for mercury, and dated by the lead-210 method. In general the cores exhibit a mercury profile with higher mercury concentrations in the upper centimetres of the core. The cores were studied by linear regression of In Hg vs, age...... indicating that the mercury mainly originates from atmospheric washout. But the large variability indicates that other processes also influence the mercury flux to Arctic marine sediments. (C) 2000 Elsevier Science B.V. All rights reserved....

Mercury kinetics in marine zooplankton

International Nuclear Information System (INIS)

Fowler, S.W.; Heyraud, M.; LaRosa, J.

1976-01-01

Mercury, like many other heavy metals, is potentially available to marine animals by uptake directly from water and/or through the organisms food. Furthermore, bioavailability, assimilation and subsequent retention in biota may be affected by the chemical species of the element in sea water. While mercury is known to exist in the inorganic form in sea water, recent work has indicated that, in certain coastal areas, a good portion of the total mercury appears to be organically bound; however, the exact chemical nature of the organic fraction has yet to be determined. Methyl mercury may be one constituent of the natural organically bound fraction since microbial mechanisms for in situ methylation of mercury have been demonstrated in the aquatic environment. Despite the fact that naturally produced methyl mercury probably comprises only a small fraction of an aquatic ecosystem, the well-documented toxic effects of this organo-mercurial, caused by man-made introductions into marine food chains, make it an important compound to study

The secondary release of mercury in coal fly ash-based flue-gas mercury removal technology.

Science.gov (United States)

He, Jingfeng; Duan, Chenlong; Lei, Mingzhe; Zhu, Xuemei

2016-01-01

The secondary release of mercury from coal fly ash is a negative by-product from coal-fired power plants, and requires effective control to reduce environmental pollution. Analysing particle size distribution and composition of the coal fly ash produced by different mercury removing technologies indicates that the particles are generally less than 0.5 mm in size and are composed mainly of SiO2, Al2O3, and Fe2O3. The relationships between mercury concentration in the coal fly ash, its particle size, and loss of ignition were studied using different mercury removing approaches. The research indicates that the coal fly ash's mercury levels are significantly higher after injecting activated carbon or brominating activated carbon when compared to regular cooperating-pollution control technology. This is particularly true for particle size ranges of >0.125, 0.075-0.125, and 0.05-0.075 mm. Leaching experiments revealed the secondary release of mercury in discarded coal fly ash. The concentration of mercury in the coal fly ash increases as the quantity of injecting activated carbon or brominating activated carbon increases. The leached concentrations of mercury increase as the particle size of the coal fly ash increases. Therefore, the secondary release of mercury can be controlled by adding suitable activated carbon or brominating activated carbon when disposing of coal fly ash. Adding CaBr2 before coal combustion in the boiler also helps control the secondary release of mercury, by increasing the Hg(2+) concentration in the leachate. This work provides a theoretical foundation for controlling and removing mercury in coal fly ash disposal.

Biomarkers of mercury exposure at a mercury recycling facility in Ukraine.

Science.gov (United States)

Gibb, Herman Jones; Kozlov, Kostj; Buckley, Jessie Poulin; Centeno, Jose; Jurgenson, Vera; Kolker, Allan; Conko, Kathryn; Landa, Edward; Panov, Boris; Panov, Yuri; Xu, Hanna

2008-08-01

This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those who worked at the facility but not in the yard where the recycling was done (Group B, n = 14), and (3) those who did not work at the facility (Group C, n = 7). Urine, blood, hair, and nail samples were collected from the participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in the former mercury mine/smelter located on the site of the recycling facility. Each factor was tested in a univariate regression with total mercury in urine, blood, hair, and nails. Median biomarker concentrations were 4.04 microg/g-Cr (urine), 2.58 microg/L (blood), 3.95 microg/g (hair), and 1.16 microg/g (nails). Occupational category was significantly correlated (p recycling operation had the highest blood and urinary mercury levels. Those who worked at the facility but were not directly involved with the recycling operation had higher levels than those who did not work at the facility.

Mercury Emission Control Technologies for PPL Montana-Colstrip Testing

Energy Technology Data Exchange (ETDEWEB)

John P. Kay; Michael L. Jones; Steven A. Benson

2007-04-01

technique at Colstrip is not seen. All the additives injected resulted in some reduction in mercury emissions. However, the target reduction of 55% was not achieved. The primary reason for the lower removal rates is because of the lower levels of mercury in the flue gas stream and the lower capture level of fine particles by the scrubbers (relative to that for larger particles). The reaction and interaction of the SEA materials is with the finer fraction of the fly ash, because the SEA materials are vaporized during the combustion or reaction process and condense on the surfaces of entrained particles or form very small particles. Mercury will have a tendency to react and interact with the finer fraction of entrained ash and sorbent as a result of the higher surface areas of the finer particles. The ability to capture the finer fraction of fly ash is the key to controlling mercury. Cost estimates for mercury removal based on the performance of each sorbent during this project are projected to be extremely high. When viewed on a dollar-per-pound-of-mercury removed basis activated carbon was projected to cost nearly $1.2 million per pound of mercury removed. This value is roughly six times the cost of other sorbent-enhancing agents, which were projected to be closer to $200,000 per pound of mercury removed.

Mercury dynamics in a coastal aquifer: Maunalua Bay, Oʻahu, Hawaiʻi

Science.gov (United States)

Ganguli, Priya M.; Swarzenski, Peter W.; Dulaiova, Henrieta; Glenn, Craig R.; Flegal, A. Russell

2014-01-01

We evaluated the influence of groundwater–seawater interaction on mercury dynamics in Maunalua Bay, a coral reef ecosystem located on the south shore of Oʻahu, Hawaiʻi, by combining geochemical data with submarine groundwater discharge (SGD) rates. During a rising tide, unfiltered total mercury (U-HgT) concentrations in seawater increased from ∼6 to 20 pM at Black Point (west Bay) and from ∼2.5 to 8 pM at Niu (central Bay). We attribute this change to an increase in suspended particulate matter at high tide. Approximately 90% of mercury in groundwater at Niu was in the filtered (weighted average Maunalua Bay groundwater mercury flux of 0.68 ± 0.67 mol yr−1 by combining the proportional flux of F-HgT from three distinct SGD zones, and place these results into a broader context by comparing and contrasting flux estimates from locations around the world. Results from existing SGD studies should be evaluated to develop future sampling strategies that address more targeted questions about mercury biogeochemical cycling at the groundwater–seawater interface.

Groundwater Modeling Of Mercury Pollution At A Former Mercury Cell Chlor Alkali Facility In Pavoldar, Kazakhstan

Science.gov (United States)

In Kazakhstan, there is a serious case of mercury pollution near the city of Pavlodar from an old mercury cell chlor-alkali plant. The soil, sediment, and water is severly contaminated with mercury and mercury compounds as a result of the industrial activity of this chemical pla...

Process for low mercury coal

Science.gov (United States)

Merriam, Norman W.; Grimes, R. William; Tweed, Robert E.

1995-01-01

A process for producing low mercury coal during precombustion procedures by releasing mercury through discriminating mild heating that minimizes other burdensome constituents. Said mercury is recovered from the overhead gases by selective removal.

Current and future levels of mercury atmospheric pollution on a global scale

Science.gov (United States)

Pacyna, Jozef M.; Travnikov, Oleg; De Simone, Francesco; Hedgecock, Ian M.; Sundseth, Kyrre; Pacyna, Elisabeth G.; Steenhuisen, Frits; Pirrone, Nicola; Munthe, John; Kindbom, Karin

2016-10-01

research instrument for supporting the scientific justification for the Minamata Convention and monitoring of the implementation of targets of this convention, as well as the EU Mercury Strategy. This project provided the state of the art with regard to the development of the latest emission inventories for mercury, future emission scenarios, dispersion modelling of atmospheric mercury on a global and regional scale, and source-receptor techniques for mercury emission apportionment on a global scale.

Current and future levels of mercury atmospheric pollution on a global scale

Directory of Open Access Journals (Sweden)

J. M. Pacyna

2016-10-01

proved to be a very important research instrument for supporting the scientific justification for the Minamata Convention and monitoring of the implementation of targets of this convention, as well as the EU Mercury Strategy. This project provided the state of the art with regard to the development of the latest emission inventories for mercury, future emission scenarios, dispersion modelling of atmospheric mercury on a global and regional scale, and source–receptor techniques for mercury emission apportionment on a global scale.

Mercury's magnetic field and interior

International Nuclear Information System (INIS)

Connerney, J.E.P.; Ness, N.F.

1988-01-01

The magnetic-field data collected on Mercury by the Mariner-10 spacecraft present substantial evidence for an intrinsic global magnetic field. However, studies of Mercury's thermal evolution show that it is most likely that the inner core region of Mercury solidified or froze early in the planet's history. Thus, the explanation of Mercury's magnetic field in the framework of the traditional planetary dynamo is less than certain

Multi-model study of mercury dispersion in the atmosphere: vertical and interhemispheric distribution of mercury species

Directory of Open Access Journals (Sweden)

J. Bieser

2017-06-01

Full Text Available Atmospheric chemistry and transport of mercury play a key role in the global mercury cycle. However, there are still considerable knowledge gaps concerning the fate of mercury in the atmosphere. This is the second part of a model intercomparison study investigating the impact of atmospheric chemistry and emissions on mercury in the atmosphere. While the first study focused on ground-based observations of mercury concentration and deposition, here we investigate the vertical and interhemispheric distribution and speciation of mercury from the planetary boundary layer to the lower stratosphere. So far, there have been few model studies investigating the vertical distribution of mercury, mostly focusing on single aircraft campaigns. Here, we present a first comprehensive analysis based on various aircraft observations in Europe, North America, and on intercontinental flights. The investigated models proved to be able to reproduce the distribution of total and elemental mercury concentrations in the troposphere including interhemispheric trends. One key aspect of the study is the investigation of mercury oxidation in the troposphere. We found that different chemistry schemes were better at reproducing observed oxidized mercury patterns depending on altitude. High concentrations of oxidized mercury in the upper troposphere could be reproduced with oxidation by bromine while elevated concentrations in the lower troposphere were better reproduced by OH and ozone chemistry. However, the results were not always conclusive as the physical and chemical parameterizations in the chemistry transport models also proved to have a substantial impact on model results.

Vertical Distribution of Total Mercury and Mercury Methylation in a Landfill Site in Japan

Directory of Open Access Journals (Sweden)

Jing Yang

2018-06-01

Full Text Available Mercury is a neurotoxin, with certain organic forms of the element being particularly harmful to humans. The Minamata Convention was adopted to reduce the intentional use and emission of mercury. Because mercury is an element, it cannot be decomposed. Mercury-containing products and mercury used for various processes will eventually enter the waste stream, and landfill sites will become a mercury sink. While landfill sites can be a source of mercury pollution, the behavior of mercury in solid waste within a landfill site is still not fully understood. The purpose of this study was to determine the depth profile of mercury, the levels of methyl mercury (MeHg, and the factors controlling methylation in an old landfill site that received waste for over 30 years. Three sampling cores were selected, and boring sampling was conducted to a maximum depth of 18 m, which reached the bottom layer of the landfill. Total mercury (THg and MeHg were measured in the samples to determine the characteristics of mercury at different depths. Bacterial species were identified by 16S rRNA amplification and sequencing, because the methylation process is promoted by a series of genes. It was found that the THg concentration was 19–975 ng/g, with a geometric mean of 298 ng/g, which was slightly less than the 400 ng/g concentration recorded 30 years previously. In some samples, MeHg accounted for up to 15–20% of THg, which is far greater than the general level in soils and sediments, although the source of MeHg was unclear. The genetic data indicated that hgcA was present mostly in the upper and lower layers of the three cores, merA was almost as much as hgcA, while the level of merB was hundreds of times less than those of the other two genes. A significant correlation was found between THg and MeHg, as well as between MeHg and MeHg/THg. In addition, a negative correlation was found between THg and merA. The coexistence of the three genes indicated that both

Mercury (Environmental Health Student Portal)

Science.gov (United States)

... in contact with) to mercury is by eating fish or shellfish that have high levels of mercury. You can also get sick from: Touching it Breathing it in Drinking contaminated water How can mercury ...

Experimental Investigation of Magnetohydrodynamics Effects in Molten Metals and Study of Homogeneity of Radioactive Mercury Amalgams

CERN Document Server

Astone, A

2002-01-01

The high neutrino output demanded for a neutri no factory requests a high power proton beam interacting with a static target. The additional circumstances of limited space and long term stability ask for development of novel concepts for such types of targets. In our working group, part of the Neutri no Factory Working Group (NFWG) of CERN, we are investigating on the proton interaction with the mercury target. This is called the study of proton induced shocks in molten metal. In the US scheme for a neutrino factory the interaction between proton beam and the mercury jet target takes place inside a 20 Tesla solenoidal magnetic field, which serv es as a focusing device for the produced particles. This field of study is refe rred to as Magneto Hydrodynamics (MHD). The high power proton beam deposits a large amount of energy in the small volume of the target, which results in disruption. The aim is to establi...

Elimination of mercury in health care facilities.

Science.gov (United States)

2000-03-01

Mercury is a persistent, bioaccumulative toxin that has been linked to numerous health effects in humans and wildlife. It is a potent neurotoxin that may also harm the brain, kidneys, and lungs. Unborn children and young infants are at particular risk for brain damage from mercury exposure. Hospitals' use of mercury in chemical solutions, thermometers, blood pressure gauges, batteries, and fluorescent lamps makes these facilities large contributors to the overall emission of mercury into the environment. Most hospitals recognize the dangers of mercury. In a recent survey, four out of five hospitals stated that they have policies in place to eliminate the use of mercury-containing products. Sixty-two percent of them require vendors to disclose the presence of mercury in chemicals that the hospitals purchase. Only 12 percent distribute mercury-containing thermometers to new parents. Ninety-two percent teach their employees about the health and environmental effects of mercury, and 46 percent teach all employees how to clean up mercury spills. However, the same study showed that many hospitals have not implemented their policies. Forty-two percent were not aware whether they still purchased items containing mercury. In addition, 49 percent still purchase mercury thermometers, 44 percent purchase mercury gastrointestinal diagnostic equipment, and 64 percent still purchase mercury lab thermometers.

Mercury

CERN Document Server

Balogh, André; Steiger, Rudolf

2008-01-01

Mercury, the planet closest to the Sun, is different in several respects from the other three terrestrial planets. In appearance, it resembles the heavily cratered surface of the Moon, but its density is high, it has a magnetic field and magnetosphere, but no atmosphere or ionosphere. This book reviews the progress made in Mercury studies since the flybys by Mariner 10 in 1974-75, based on the continued research using the Mariner 10 archive, on observations from Earth, and on increasingly realistic models of its interior evolution.

Autometallographic tracing of mercury in frog liver

International Nuclear Information System (INIS)

Loumbourdis, N.S.; Danscher, G.

2004-01-01

The distribution of mercury in the liver of the frog Rana ridibunda with the autometallographic method was investigated. The mercury specific autometallographic (HgS/Se AMG ) technique is a sensitive histochemical approach for tracing mercury in tissues from mercury-exposed organisms. Mercury accumulates in vivo as mercury sulphur/mercury selenium nanocrystals that can be silver-enhanced. Thus, only a fraction of the Hg can be visualized. Six animals were exposed for one day and another group of six animals for 6 days in 1 ppm mercury (as HgCI 2 ) dissolved in fresh water. A third group of six animals, served as controls, were sacrificed the day of arrival at the laboratory. First, mercury appears in the blood plasma and erythrocytes. Next, mercury moves to hepatocytes and in the apical part of the cells, that facing bile canaliculi. In a next step, mercury appears in the endothelial and Kupffer cells. It seems likely that, the mercury of hepatocytes moves through bile canaliculi to the gut, most probably bound to glutathione and/or other similar ligands. Most probably, the endothelial and Kupffer cells comprise the first line of defense against metal toxicity. - Frogs can be good bioindicators of mercury

Mercury stable isotope signatures of world coal deposits and historical coal combustion emissions.

Science.gov (United States)

Sun, Ruoyu; Sonke, Jeroen E; Heimbürger, Lars-Eric; Belkin, Harvey E; Liu, Guijian; Shome, Debasish; Cukrowska, Ewa; Liousse, Catherine; Pokrovsky, Oleg S; Streets, David G

2014-07-01

Mercury (Hg) emissions from coal combustion contribute approximately half of anthropogenic Hg emissions to the atmosphere. With the implementation of the first legally binding UNEP treaty aimed at reducing anthropogenic Hg emissions, the identification and traceability of Hg emissions from different countries/regions are critically important. Here, we present a comprehensive world coal Hg stable isotope database including 108 new coal samples from major coal-producing deposits in South Africa, China, Europe, India, Indonesia, Mongolia, former USSR, and the U.S. A 4.7‰ range in δ(202)Hg (-3.9 to 0.8‰) and a 1‰ range in Δ(199)Hg (-0.6 to 0.4‰) are observed. Fourteen (p coal Hg emissions tracing. A revised coal combustion Hg isotope fractionation model is presented, and suggests that gaseous elemental coal Hg emissions are enriched in the heavier Hg isotopes relative to oxidized forms of emitted Hg. The model explains to first order the published δ(202)Hg observations on near-field Hg deposition from a power plant and global scale atmospheric gaseous Hg. Yet, model uncertainties appear too large at present to permit straightforward Hg isotope source identification of atmospheric forms of Hg. Finally, global historical (1850-2008) coal Hg isotope emission curves were modeled and indicate modern-day mean δ(202)Hg and Δ(199)Hg values for bulk coal emissions of -1.2 ± 0.5‰ (1SD) and 0.05 ± 0.06‰ (1SD).

Fatigue properties of type 316LN stainless steel in air and mercury

International Nuclear Information System (INIS)

Strizak, J.P.; Tian, H.; Liaw, P.K.; Mansur, L.K.

2005-01-01

An extensive fatigue testing program on 316LN stainless steel was recently carried out to support the design of the mercury target container for the spallation neutron source (SNS) that is currently under construction at the Oak Ridge National Laboratory in the United States. The major objective was to determine the effects of mercury on fatigue behavior. The S-N fatigue behavior of 316LN stainless steel is characterized by a family of bilinear fatigue curves which are dependent on frequency, environment, mean stress and cold work. Generally, fatigue life increases with decreasing stress and levels off in the high cycle region to an endurance limit below which the material will not fail. For fully reversed loading as well as tensile mean stress loading conditions mercury had no effect on endurance limit. However, at higher stresses a synergistic relationship between mercury and cyclic loading frequency was observed at low frequencies. As expected, fatigue life decreased with decreasing frequency, but the response was more pronounced in mercury compared with air. As a result of liquid metal embrittlement (LME), fracture surfaces of specimens tested in mercury showed widespread brittle intergranular cracking as opposed to typical transgranular cracking for specimens tested in air. For fully reversed loading (zero mean stress) the effect of mercury disappeared as frequency increased to 10 Hz. For mean stress conditions with R-ratios of 0.1 and 0.3, LME was still evident at 10 Hz, but at 700 Hz the effect of mercury had disappeared (R 0.1). Further, for higher R-ratios (0.5 and 0.75) fatigue curves for 10 Hz showed no environmental effect. Finally, cold working (20%) increased tensile strength and hardness, and improved fatigue resistance. Fatigue behavior at 10 and 700 Hz was similar and no environmental effect was observed

Fatigue properties of type 316LN stainless steel in air and mercury

Science.gov (United States)

Strizak, J. P.; Tian, H.; Liaw, P. K.; Mansur, L. K.

2005-08-01

An extensive fatigue testing program on 316LN stainless steel was recently carried out to support the design of the mercury target container for the spallation neutron source (SNS) that is currently under construction at the Oak Ridge National Laboratory in the United States. The major objective was to determine the effects of mercury on fatigue behavior. The S- N fatigue behavior of 316LN stainless steel is characterized by a family of bilinear fatigue curves which are dependent on frequency, environment, mean stress and cold work. Generally, fatigue life increases with decreasing stress and levels off in the high cycle region to an endurance limit below which the material will not fail. For fully reversed loading as well as tensile mean stress loading conditions mercury had no effect on endurance limit. However, at higher stresses a synergistic relationship between mercury and cyclic loading frequency was observed at low frequencies. As expected, fatigue life decreased with decreasing frequency, but the response was more pronounced in mercury compared with air. As a result of liquid metal embrittlement (LME), fracture surfaces of specimens tested in mercury showed widespread brittle intergranular cracking as opposed to typical transgranular cracking for specimens tested in air. For fully reversed loading (zero mean stress) the effect of mercury disappeared as frequency increased to 10 Hz. For mean stress conditions with R-ratios of 0.1 and 0.3, LME was still evident at 10 Hz, but at 700 Hz the effect of mercury had disappeared ( R = 0.1). Further, for higher R-ratios (0.5 and 0.75) fatigue curves for 10 Hz showed no environmental effect. Finally, cold working (20%) increased tensile strength and hardness, and improved fatigue resistance. Fatigue behavior at 10 and 700 Hz was similar and no environmental effect was observed.

Method and apparatus for sampling atmospheric mercury

Science.gov (United States)

Trujillo, Patricio E.; Campbell, Evan E.; Eutsler, Bernard C.

1976-01-20

A method of simultaneously sampling particulate mercury, organic mercurial vapors, and metallic mercury vapor in the working and occupational environment and determining the amount of mercury derived from each such source in the sampled air. A known volume of air is passed through a sampling tube containing a filter for particulate mercury collection, a first adsorber for the selective adsorption of organic mercurial vapors, and a second adsorber for the adsorption of metallic mercury vapor. Carbon black molecular sieves are particularly useful as the selective adsorber for organic mercurial vapors. The amount of mercury adsorbed or collected in each section of the sampling tube is readily quantitatively determined by flameless atomic absorption spectrophotometry.

Methods for dispensing mercury into devices

Science.gov (United States)

Grossman, Mark W.; George, William A.

1987-04-28

A process for dispensing mercury into devices which requires mercury. Mercury is first electrolytically separated from either HgO or Hg.sub.2 Cl.sub.2 and plated onto a cathode wire. The cathode wire is then placed into a device requiring mercury.

Streamwater fluxes of total mercury and methylmercury into and out of Lake Champlain

International Nuclear Information System (INIS)

Shanley, James B.; Chalmers, Ann T.

2012-01-01

From 2000 to 2004, we sampled for total mercury (THg) and methylmercury (MeHg) in inlet streams to Lake Champlain, targeting high flow periods to capture increases in THg and MeHg concentrations with increasing flow. We used these data to model stream THg and MeHg fluxes for Water Years 2001 through 2009. In this mountainous forested basin with a high watershed-to-lake area ratio of 18, fluvial export from the terrestrial watershed was the dominant source of Hg to the lake. Unfiltered THg and MeHg fluxes were dominated by the particulate fraction; about 40% of stream THg was in the filtered ( −2 yr −1 , or about 13% of atmospheric Hg wet and dry deposition to the basin. THg export from the lake represented only about 3% of atmospheric Hg input to the basin. - Highlights: ► We monitored total mercury and methylmercury in major tributaries to Lake Champlain. ► Mercury and methylmercury export was primarily as particulates during high flow. ► Only 13% of atmospheric total mercury input reached the lake via streams. ► Only 3% of atmospheric total mercury input reached the lake outlet. - Eighty-seven percent of total mercury deposition to the Lake Champlain basin is retained in the terrestrial basin; stream export of total and methylmercury to the lake is primarily in the particulate phase.

Histochemical demonstration of two mercury pools in trout tissues: mercury in kidney and liver after mercuric chloride exposure

DEFF Research Database (Denmark)

Baatrup, E; Nielsen, M G; Danscher, G

1987-01-01

Juvenile rainbow trout (Salmo gairdneri) were exposed to 100 ppb mercury (as HgCl2) in the water for 14 days. Concentrations of mercury in water and fish organs were monitored using radiolabeled mercury. Tissues from kidney and liver were fixed, and sections were developed by autometallography......, a method whereby accumulations of mercury sulfides and/or mercury selenides are silver amplified. In the kidney, mercury was found within lysosomes and extracellularly in the basal lamina of proximal tubules. In the liver, mercury was found within lysosomes of the hepatocytes. Additional groups of mercury......-exposed trout were subjected to selenium (as Na2SeO3), administered intraperitoneally 2 hr before fixation. Following this treatment, additional mercury could be visualized in the kidney circulatory system, including glomeruli, and in the nucleus and endoplasmic reticulum of liver cells. It is suggested...

Mercury uptake in vivo by normal and acatalasemic mice exposed to metallic mercury vapor (203Hg degrees) and injected with metallic mercury or mercuric chloride (203HgCl2)

International Nuclear Information System (INIS)

Ogata, M.; Kenmotsu, K.; Hirota, N.; Meguro, T.; Aikoh, H.

1985-01-01

Levels of mercury in the brain and liver of acatalasemic mice immediately following exposure to metallic mercury vapor or injection of metallic mercury were higher than those found in normal mice. Acatalasemic mice had decreased levels of mercury in the blood and kidneys when the levels were compared with those of normal mice, which indicated that catalase plays a role in oxidizing and taking up mercury. Thus, the brain/blood or liver/blood ratio of mercury concentration in acatalasemic mice was significantly higher than that of normal mice. These results suggest that metallic mercury in the blood easily passed through the blood-brain or blood-liver barrier. The levels of mercury distribution to the kidneys of normal and acatalasemic mice, 1 hr after injection of mercuric chloride solution, were higher than that of normal and acatalasemic mice, respectively, 1 hr after injection of metallic mercury

Target-induced formation of gold amalgamation on DNA-based sensing platform for electrochemical monitoring of mercury ion coupling with cycling signal amplification strategy

International Nuclear Information System (INIS)

Chen, Jinfeng; Tang, Juan; Zhou, Jun; Zhang, Lan; Chen, Guonan; Tang, Dianping

2014-01-01

Graphical abstract: -- Highlights: •We report a new electrochemical sensing protocol for the detection of mercury ion. •Gold amalgamation on DNA-based sensing platform was used as nanocatalyst. •The signal was amplified by cycling signal amplification strategy. -- Abstract: Heavy metal ion pollution poses severe risks in human health and environmental pollutant, because of the likelihood of bioaccumulation and toxicity. Driven by the requirement to monitor trace-level mercury ion (Hg 2+ ), herein we construct a new DNA-based sensor for sensitive electrochemical monitoring of Hg 2+ by coupling target-induced formation of gold amalgamation on DNA-based sensing platform with gold amalgamation-catalyzed cycling signal amplification strategy. The sensor was simply prepared by covalent conjugation of aminated poly-T (25) oligonucleotide onto the glassy carbon electrode by typical carbodiimide coupling. Upon introduction of target analyte, Hg 2+ ion was intercalated into the DNA polyion complex membrane based on T–Hg 2+ –T coordination chemistry. The chelated Hg 2+ ion could induce the formation of gold amalgamation, which could catalyze the p-nitrophenol with the aid of NaBH 4 and Ru(NH 3 ) 6 3+ for cycling signal amplification. Experimental results indicated that the electronic signal of our system increased with the increasing Hg 2+ level in the sample, and has a detection limit of 0.02 nM with a dynamic range of up to 1000 nM Hg 2+ . The strategy afforded exquisite selectivity for Hg 2+ against other environmentally related metal ions. In addition, the methodology was evaluated for the analysis of Hg 2+ in spiked tap-water samples, and the recovery was 87.9–113.8%

Mercury content in Hot Springs

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, R

1974-01-01

A method of determination of mercury in hot spring waters by flameless atomic absorption spectrophotometry is described. Further, the mercury content and the chemical behavior of the elementary mercury in hot springs are described. Sulfide and iodide ions interfered with the determination of mercury by the reduction-vapor phase technique. These interferences could, however, be minimized by the addition of potassium permanganate. Waters collected from 55 hot springs were found to contain up to 26.0 ppb mercury. High concentrations of mercury have been found in waters from Shimoburo Springs, Aomori (10.0 ppb), Osorezan Springs, Aomori (1.3 approximately 18.8 ppb), Gosyogake Springs, Akita (26.0 ppb), Manza Springs, Gunma (0.30 approximately 19.5 ppb) and Kusatu Springs, Gunma (1.70 approximately 4.50 ppb). These hot springs were acid waters containing a relatively high quantity of chloride or sulfate.

Diagnostic value of combined determination of serum CA19-9 and TGF-β contents in patients with pancreatic cancer

International Nuclear Information System (INIS)

Gong Zheng

2008-01-01

Objective: To study the clinical diagnostic value of combined determination of serum contents of CA19-9 and TGF-β in patients with pancreatic cancer. Methods: Serum CA19-9 (with RIA) and TGF-β (with ELISA) contents were deter- mined in 30 patients with pancreatic cancer and 35 controls. Results: The serum CA19-9 and TGF-β contents in patients with pancreatic cancer were significantly higher than those in controls (P<0.01). The diagnostic sensitivity of CA19-9 for pancreatic cancer was 70.8%, lower than that of TGF-β (80.2%, P<0.05). The diagnostic specificity of CA19-9 and TGF-β was 90.2% and 93.4% respectively. Conclusion: Both determinations of serum CA19-9 and TGF-β contents would yield high specificity for diagnosis of pancreatic cancer. Sensitity of TGF-β determination was higher than that of CA19-9 determination. Combined determination of CA19-9 and TGF-β would improve the diagnostic accuracy in patients with pancreatic cancer. (authors)

Method and apparatus for monitoring mercury emissions

Science.gov (United States)

Durham, Michael D.; Schlager, Richard J.; Sappey, Andrew D.; Sagan, Francis J.; Marmaro, Roger W.; Wilson, Kevin G.

1997-01-01

A mercury monitoring device that continuously monitors the total mercury concentration in a gas. The device uses the same chamber for converting speciated mercury into elemental mercury and for measurement of the mercury in the chamber by radiation absorption techniques. The interior of the chamber is resistant to the absorption of speciated and elemental mercury at the operating temperature of the chamber.

Clinical experience with the new tumor-associated antigen CA 19-9 compared with CEA in different neoplasms

Energy Technology Data Exchange (ETDEWEB)

Pfeiffer, R.; Dimitriadis, K.; Giesche, U.; Aulbert, E.; Hoffmann, B.; Schmidt, C.G.; Balzer, K.

1984-10-01

A new tumour-associated antigen was recently reported by Koprowski. It can be detected in human serum by a monoclonal antibody. This antigen CA 19-9 was determined in 498 patients, and simultaneous determinations of CEA were performed in 468 patients. The patients were divided into five groups: 77 non-malignant diseases of the gastrointestinal tract, 55 gastrointestinal cancer, 174 breast cancer, 101 lung cancer, and 61 other neoplasms. We found nearly the same frequency of positive CA 19-9 and CEA specimens. In the group of gastrointestinal cancer with clinically confirmed tumour 56.5% of the serum specimens were CEA positive and 54.3% were CA 19-9 positive. No patient with chronic pancreatitis (n = 11) was CA 19-9 positive, but three were CEA positive. In female breast cancer we found 48.7% CEA positive and 15.4% CA 19-9 positive, in lung cancer 40.6% CEA positive and only 11.5% CA 19-9 positive. CA 19-9 appears to be superior to CEA with respect to the discrimination of non-malignant and malignant diseases of the pancreas. The sensitivity is not sufficient for the early diagnosis of pancreatic carcinoma. In the other gastrointestinal malignomas discordant levels of both markers were detected in 10% of the patients. This means an improvement of cancer detection. The sensitivity of CA 19-9 is apparently not sufficient for breast and lung cancer.

Myocardial scintigraphy with 199Tl chloride for the assessment of antianginal effect of cardil

International Nuclear Information System (INIS)

Chernov, V.I.; Mordovin, V.F.; Vesnina, Zh.V.; Triss, S.V.; Bazilevich, I.A.; Lishmanov, Yu.B.

1995-01-01

The aim of this research was examination of myocardial perfusion in cardil therapy of twenty-two coronary patients and analysis of potentialities of load 199 Tl scintigraphy in assessment of the antianginal effect in the course of therapy of coronary patients. The findings evidence that due to short 199 Tl half life and low radiation load of the body because of this radionuclide load 199 Tl scintigraphy of the myocardium carried out in the course of therapy of coronary patients may be used as an objective test to assess myocardial perfusion under the effect of treatment. 8 refs

Return to Mercury: a global perspective on MESSENGER's first Mercury flyby.

Science.gov (United States)

Solomon, Sean C; McNutt, Ralph L; Watters, Thomas R; Lawrence, David J; Feldman, William C; Head, James W; Krimigis, Stamatios M; Murchie, Scott L; Phillips, Roger J; Slavin, James A; Zuber, Maria T

2008-07-04

In January 2008, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft became the first probe to fly past the planet Mercury in 33 years. The encounter revealed that Mercury is a dynamic system; its liquid iron-rich outer core is coupled through a dominantly dipolar magnetic field to the surface, exosphere, and magnetosphere, all of which interact with the solar wind. MESSENGER images confirm that lobate scarps are the dominant tectonic landform and record global contraction associated with cooling of the planet. The history of contraction can be related to the history of volcanism and cratering, and the total contractional strain is at least one-third greater than inferred from Mariner 10 images. On the basis of measurements of thermal neutrons made during the flyby, the average abundance of iron in Mercury's surface material is less than 6% by weight.

Mercury: Aspects of its ecology and environmental toxicity. [physiological effects of mercury compound contamination of environment

Science.gov (United States)

Siegel, S. M.

1973-01-01

A study was conducted to determine the effects of mercury pollution on the environment. The possible sources of mercury contamination in sea water are identified. The effects of mercury on food sources, as represented by swordfish, are analyzed. The physiological effects of varying concentrations of mercury are reported. Emphasis is placed on the situation existing in the Hawaiian Islands.

Axial mercury segregation in direct current operated low-pressure argon-mercury gas discharges: Part I. Experimental

International Nuclear Information System (INIS)

Gielen, John W A M; Groot, Simon de; Mullen, Joost J A M van der

2004-01-01

Due to cataphoresis, axial segregation of mercury will occur when the gas discharge of a fluorescent lamp is operated by means of a direct current. A consequence of this is a non-uniform axial luminance distribution along the lamp. To determine the degree of axial mercury segregation experimentally, axial luminance distributions have been measured which are converted into axial mercury vapour pressure distributions by an appropriate calibration method. The mercury segregation has been investigated for variations in lamp tube radius (3.6-4.8 mm), argon buffer gas pressure (200-600 Pa) and lamp current (100-250 mA) at mercury vapour pressures set at the anode in the range from 0.2 to 9.0 Pa. From the experiments it has been concluded that the mercury vapour pressure gradient at any axial position for a certain lamp tube diameter, argon pressure and lamp current depends on the local mercury vapour pressure. This observation is in contrast to assumptions made in earlier modelling publications in which one mercury vapour pressure gradient is used for all axial positions. By applying a full factorial design, an empirical relation of the mercury segregation is found for any set of parameters inside the investigated parameter ranges

Mercury Sorption onto Malt Spent Rootlets

Science.gov (United States)

Manariotis, I. D.; Anagnostopoulos, V.; Karapanagioti, H. K.; Chrysikopoulos, C.

2011-12-01

Mercury is a metal of particular concern due to its toxicity even at relatively low concentrations. The maximum permissible level for mercury in drinking water set by the European Union is 0.001 mg/L. Mercury is released into the environment via four principal pathways: (1) natural processes; i.e. a volcanic eruption, (2) incidental to some other activity; i.e. coal burning power plants, (3) accidentally during the manufacture, breakage or disposal of products that have mercury put into them deliberately, and (4) direct use in industrial settings. The present study focuses on the removal of mercury (II) from aqueous solutions via sorption onto Malt Spent Rootlets (MSR). Batch experiments were conducted employing MSR with size ranging from 0.18 to 1 mm. The effects of pH, mercury concentration, contact time, and solid to liquid ratio on mercury sorption onto MSR were investigated. The highest mercury removal from the aqueous phase, of 41%, was observed at pH of 5.

Metastatic prostate cancer with elevated serum levels of CEA and CA19-9

Directory of Open Access Journals (Sweden)

Guang-Dar Juang

2014-03-01

Full Text Available Prostate-specific antigen (PSA is well known as a specific tumor marker for prostate cancer, but carcinoembryonic antigen (CEA- and carbohydrate antigen 19-9 (CA19-9-elevating adenocarcinomas originating in the prostate gland are rare. We report a case of metastatic adenocarcinoma of the prostate gland with a high serum level of CEA and CA19-9 in a 78-year-old man in whom prostate cancer (T3N1M1 had been diagnosed 2 years ago and who was treated with androgen deprivation therapy. He visited the emergency department because of a loss of appetite and abdominal pain. The serum CEA and CA19-9 levels were increased to 218.9 ng/mL (normal, <5 ng/mL and 212 ng/mL (normal, <27 ng/mL, respectively. The serum PSA level was slightly elevated (4.41 ng/mL. Computed tomography demonstrated multiple liver metastases, para-aortic lymph node enlargement, and lung metastases. A liver biopsy was performed and the specimen showed high-grade adenocarcinoma with focal positive staining for PSA. Despite chemotherapy with docetaxel, the patient died 3 months after treatment. Based on this case and a review of the literature, an aggressive variant of prostatic carcinoma with a high serum level of CEA and CA19-9 and a low PSA level was shown to progress rapidly with a poor prognosis.

Novel methodology for the study of mercury methylation and reduction in sediments and water using 197Hg radiotracer

International Nuclear Information System (INIS)

Ribeiro Guevara, Sergio; Perez Catan, Soledad; Zizek, Suzana; Repinc, Urska; Jacimovic, Radojko; Horvat, Milena

2007-01-01

Mercury tracers are powerful tools that can be used to study mercury transformations in environmental systems, particularly mercury methylation, demethylation and reduction in sediments and water. However, mercury transformation studies using tracers can be subject to error, especially when used to assess methylation potential. The organic mercury extracted can be as low as 0.01% of the endogenous labeled mercury, and artefacts and contamination present during methylmercury (MeHg) extraction processes can cause interference. Solvent extraction methods based on the use of either KBr/H 2 SO 4 or HCl were evaluated in freshwater sediments using 197 Hg radiotracer. Values obtained for the 197 Hg tracer in the organic phase were up to 25-fold higher when HCl was used, which is due to the coextraction of 197 Hg 2+ into the organic phase during MeHg extraction. Evaluations of the production of MeHg gave similar results with both MeHg extraction procedures, but due to the higher Hg 2+ contamination of the controls, the uncertainty in the determination was higher when HCl was used. The Hg 2+ contamination of controls in the HCl extraction method showed a nonlinear correlation with the humic acid content of sediment pore water. Therefore, use of the KBr/H 2 SO 4 method is recommended, since it is free from these interferences. 197 Hg radiotracer (T 1/2 = 2.673 d) has a production rate that is about 50 times higher than that of 203 Hg (T 1/2 46.595 d), the most frequently used mercury radiotracer. Hence it is possible to obtain a similar level of performance to 203 Hg when it is used it in short-term experiments and produced by the irradiation of 196 Hg with thermal neutrons, using mercury targets with the natural isotopic composition. However, if the 0.15% natural abundance of the 196 Hg isotope is increased, the specific activity of the 197 Hg tracer can be significantly improved. In the present work, 197 Hg tracer was produced from mercury 51.58% enriched in the 196 Hg

Adjusting CA19-9 values to predict malignancy in obstructive jaundice: Influence of bilirubin and C-reactive protein

Science.gov (United States)

La Greca, Gaetano; Sofia, Maria; Lombardo, Rosario; Latteri, Saverio; Ricotta, Agostino; Puleo, Stefano; Russello, Domenico

2012-01-01

AIM: To find a possible relationship between inflammation and CA19-9 tumor marker by analyzing data from patients with benign jaundice (BJ) and malignant jaundice (MJ). METHODS: All patients admitted for obstructive jaundice, in the period 2005-2009, were prospectively enrolled in the study, obtaining a total of 102 patients. On admission, all patients underwent complete standard blood test examinations including C-reactive protein (CRP), bilirubin, CA19-9. Patients were considered eligible for the study when they presented obstructive jaundice confirmed by instrumental examinations and increased serum bilirubin levels (total bilirubin > 2.0 mg/dL). The standard cut-off level for CA19-9 was 32 U/mL, whereas for CRP this was 1.5 mg/L. The CA19-9 level was adjusted by dividing it by the value of serum bilirubin or by the CRP value. The patients were divided into 2 groups, MJ and BJ, and after the adjustment a comparison between the 2 groups of patients was performed. Sensitivity, specificity and positive predictive values were calculated before and after the adjustment. RESULTS: Of the 102 patients, 51 were affected by BJ and 51 by MJ. Pathologic CA19-9 levels were found in 71.7% of the patients. In the group of 51 BJ patients there were 29 (56.9%) males and 22 (43.1%) females with a median age of 66 years (range 24-96 years), whereas in the MJ group there were 24 (47%) males and 27 (53%) females, with a mean age of 70 years (range 30-92 years). Pathologic CA19-9 serum level was found in 82.3% of MJ. CRP levels were pathologic in 66.6% of the patients with BJ and in 49% with MJ. Bilirubin and CA19-9 average levels were significantly higher in MJ compared with BJ (P = 0.000 and P = 0.02), while the CRP level was significantly higher in BJ (P = 0.000). Considering a CA19-9 cut-off level of 32 U/mL, 82.3% in the MJ group and 54.9% in the BJ group were positive for CA19-9 (P = 0.002). A CA19-9 cut-off of 100 U/mL increases the difference between the two groups: 35.3% in

Mercury Exposure: Protein Biomarkers of Mercury Exposure in Jaraqui Fish from the Amazon Region.

Science.gov (United States)

Vieira, José Cavalcante Souza; Braga, Camila Pereira; de Oliveira, Grasieli; Padilha, Cilene do Carmo Federici; de Moraes, Paula Martin; Zara, Luiz Fabricio; Leite, Aline de Lima; Buzalaf, Marília Afonso Rabelo; Padilha, Pedro de Magalhães

2018-05-01

This study presents data on the extraction and characterization of proteins associated with mercury in the muscle and liver tissues of jaraqui (Semaprochilodus spp.) from the Madeira River in the Brazilian Amazon. Protein fractionation was carried out by two-dimensional electrophoresis (2D-PAGE). Mercury determination in tissues, pellets, and protein spots was performed by graphite furnace atomic absorption spectrometry (GFAAS). Proteins in the spots that showed mercury were characterized by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The highest mercury concentrations were found in liver tissues and pellets (426 ± 6 and 277 ± 4 μg kg -1 ), followed by muscle tissues and pellets (132 ± 4 and 86 ± 1 μg kg -1 , respectively). Mercury quantification in the protein spots allowed us to propose stoichiometric ratios in the range of 1-4 mercury atoms per molecule of protein in the protein spots. The proteins characterized in the analysis by ESI-MS/MS were keratin, type II cytoskeletal 8, parvalbumin beta, parvalbumin-2, ubiquitin-40S ribosomal S27a, 39S ribosomal protein L36 mitochondrial, hemoglobin subunit beta, and hemoglobin subunit beta-A/B. The results suggest that proteins such as ubiquitin-40S ribosomal protein S27a, which have specific domains, possibly zinc finger, can be used as biomarkers of mercury, whereas mercury and zinc present characteristics of soft acids.

The roles of serum and urinary carbohydrate antigen 19-9 in the management of patients with antenatal hydronephrosis.

Science.gov (United States)

Atar, Arda; Oktar, Tayfun; Kucukgergin, Canan; Kalelioglu, Ibrahim; Seckin, Sule; Ander, Haluk; Ziylan, Orhan; Kadioglu, Teoman Cem

2015-06-01

Serum carbohydrate antigen (CA) 19-9 has been clinically applied as a valuable tumor marker for pancreatic and gastrointestinal carcinoma. CA 19-9 is expressed in normal excretory epithelium tissues. Increased CA 19-9 has also been observed in uroepithelial tumors as well as in nonmalignant conditions including hydronephrosis secondary to ureteral stones. The purpose of this article is to evaluate the role of urinary CA 19-9 as a non-invasive biomarker in the postnatal differentiation of obstructive and non-obstructive hydronephrosis in patients with unilateral antenatal hydronephrosis. Infants with isolated renal pelvic dilatation, defined as the presence of anteroposterior pelvic diameter (APPD) equal to or greater than 7 mm based on antenatal ultrasound after 28 weeks' gestation, underwent systematic investigation for uropathies and were prospectively followed up. The pyeloplasty group consisted of 17 patients with ureteropelvic junction (UPJ) obstruction who had undergone pyeloplasty. The non-obstructive dilatation (NOD) group consisted of 17 patients with non-obstructive hydronephrosis, and the control group consisted of 21 healthy children. Commercial enzyme-linked immunosorbent assay (ELISA) kits were used to measure the urinary and serum CA 19-9 levels. In both hydronephrosis groups (pyeloplasty and non-obstructive dilatation), the correlations between urinary and serum CA 19-9 levels with the anteroposterior pelvic diameter measured at the third trimester and the postnatal initial evaluation and differential renal function were investigated. The initial median urinary CA 19-9 levels were significantly greater in children who underwent pyeloplasty than in both the non-obstructive hydronephrosis (143 ± 38 vs. 68 ± 23, respectively; p = 0.007) and the healthy control groups (143 ± 38 vs. 13 ± 3, respectively; p = 0.001) (Figure). Three months after surgery, the urinary CA 19-9 levels had decreased significantly according to the preoperative levels in the

Method for the removal and recovery of mercury

Science.gov (United States)

Easterly, Clay E.; Vass, Arpad A.; Tyndall, Richard L.

1997-01-01

The present invention is an enhanced method for the removal and recovery of mercury from mercury-contaminated matrices. The method involves contacting a mercury-contaminated matrix with an aqueous dispersant solution derived from specific intra-amoebic isolates to release the mercury from the mercury-contaminated matrix and emulsify the mercury; then, contacting the matrix with an amalgamating metal from a metal source to amalgamate the mercury to the amalgamating metal; removing the metallic source from the mercury-contaminated matrix; and heating the metallic source to vaporize the mercury in a closed system to capture the mercury vapors.

Isolation, screening and identification of mercury resistant bacteria from mercury contaminated soil

OpenAIRE

Kowalczyk Anna; Wilińska Magdalena; Chyc Marek; Bojko Monika; Latowski Dariusz

2016-01-01

New bacterial strains resistant to high concentration of mercury were obtained and character iz ed focusing on their potential application in bioremediation. The biological material was isolated from soil contaminated with mercury. The ability to removal of Hg from the liquid medium and the effect of the various pH and mercury concentrations in the environment on bacterial strains growth kinetics were tested. The selected strains were identified by analysis of the 16S ribosome subunit coding ...

Groundwater Modeling of Mercury Pollution at a Former Mercury Cell Chlor Alkali Facility in Pavlodar City, Kazakhstan

Science.gov (United States)

In northern Kazakhstan, there is a serious case of mercury pollution near the city of Pavlodar from an old mercury cell chlor-alkali plant. The soil, sediment, and water is severely contaminated with mercury and mercury compounds as a result of the industrial activity of this ch...

Structural dynamic response of target container against proton beam

International Nuclear Information System (INIS)

Kikuchi, Kenji; Ishikura, Syuichi; Futakawa, Masatoshi; Hino, Ryutaro

1997-01-01

Stress waves were analyzed for a target container of neutron science research project using a high-intensity proton accelerator that generates high energy and high current proton beam. In the mercury target, the pulsed proton beam generates intense power density in the course of spallation reaction and causes pressure wave in the mercury and stress wave in the target container due to a sudden temperature change. Structural integrity of the target container depends on the power intensity at a maximum energy deposit. A broad proton profile is favorable to the structural assessment of the container rather than narrow one. Stress wave have propagated in the target container at a speed of sound. It only takes 0.1 ms for the size of 40 cm length stainless steel container. Further assessment is necessary to optimize a geometry of the container and establish a method to evaluate a life time. (author)

Structural dynamic response of target container against proton beam

Energy Technology Data Exchange (ETDEWEB)

Kikuchi, Kenji; Ishikura, Syuichi; Futakawa, Masatoshi; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-11-01

Stress waves were analyzed for a target container of neutron science research project using a high-intensity proton accelerator that generates high energy and high current proton beam. In the mercury target, the pulsed proton beam generates intense power density in the course of spallation reaction and causes pressure wave in the mercury and stress wave in the target container due to a sudden temperature change. Structural integrity of the target container depends on the power intensity at a maximum energy deposit. A broad proton profile is favorable to the structural assessment of the container rather than narrow one. Stress wave have propagated in the target container at a speed of sound. It only takes 0.1 ms for the size of 40 cm length stainless steel container. Further assessment is necessary to optimize a geometry of the container and establish a method to evaluate a life time. (author)

Phytoremediation of Ionic and Methyl Mercury Pollution

Energy Technology Data Exchange (ETDEWEB)

Meagher, Richard B.

2004-12-01

Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems.

Genetic effects of organic mercury compounds

Energy Technology Data Exchange (ETDEWEB)

Ramel, C

1967-01-01

Organic mercury compounds have a c-mitotic effect on plant cells that cause polyploidi. Studies were performed on Allium root cells. These investigations involved methyl mercury dicyandiamide, methyl mercury hydroxide, and phenyl mercury hydroxide. The lowest concentration necessary for a cytologically observable effect was about 0.05 ppM Hg for the methyl compounds. For the phenyl compound, the value was lower. Experiments were performed on Drosophila melanogaster. The question was whether the mercury would reach the gonads. Experimental data with mercury treated larvae indicated a chromosome disjunction. Data indicated a preferential segregation at the meiotic division might be involved. Experiments are being performed on mice inbred (CBA) in order to investigate teratogenic effects and dominant lethality caused by organic mercury compounds. The mutagenic effects of these compounds are studied on Neurospora Drosophila. No conclusive data is now available.

Phytoremediation of Ionic and Methyl Mercury Pollution

Energy Technology Data Exchange (ETDEWEB)

Meagher, Richard B.

2005-06-01

Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

MERCURY IN MARINE LIFE DATABASE

Science.gov (United States)

The purpose of the Mercury in Marine Life Project is to organize information on estuarine and marine species so that EPA can better understand both the extent of monitoring for mercury and level of mercury contamination in the biota of coastal environments. This report follows a ...

Possible interferences of mercury sulfur compounds with ethylated and methylated mercury species using HPLC-ICP-MS

International Nuclear Information System (INIS)

Wilken, R.D.; Nitschke, F.; Falter, R.

2003-01-01

The HPLC-ICP-MS coupling technique is able to separate and detect methyl, ethyl and inorganic mercury isotopes specifically. An identification of ethyl mercury(+) is not possible when the widely used sodium tetraethylborate derivatisation method in combination with GC-AFS/AAS or ICP-MS techniques is performed because it contains ethyl groups. An unidentified compound with the same retention time as ethyl mercury was found in the HPLC chromatograms of industrial sewage samples and humic-rich soils of microcosm experiments after applying water vapour distillation. We also observed such unidentified peaks in samples of heavily contaminated sites in Eastern Germany, separated by HPLC fractionation only. In the experiments described, different mercury sulfur adducts were synthesised and tested for their retention times in the HPLC-ICP-MS system. It was found that the compound CH 3 -S-Hg + showed the same retention time as the ethyl mercury standard. It is therefore possible that ethyl mercury detected in chromatography by comparison of the retention time could also be due to an adduct of a sulfur compound and a mercury species. CH 3 -S-Hg + should be tested in other chromatographic mercury speciation methods for this effect. This work can also be regarded as a contribution to the discussion of artificially occurring methyl mercury in sediments during sample preparation. (orig.)

Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

Energy Technology Data Exchange (ETDEWEB)

Musich, Mark; Swanson, Michael; Dunham, Grant; Stanislowski, Joshua

2010-10-05

Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m{sup 3} (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m{sup 3} (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most

ADVANCED GASIFICATION MERCURY/TRACE METAL CONTROL WITH MONOLITH TRAPS

Energy Technology Data Exchange (ETDEWEB)

Mark A. Musich; Michael L. Swanson; Grant E. Dunham; Joshua J. Stanislowski

2010-07-31

Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m3 (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m3 (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most effective arsine

Advanced Emissions Control Development Program: Mercury Control

International Nuclear Information System (INIS)

Evans, A.P.; Redinger, K.W.; Holmes, M.J.

1997-07-01

selenium and mercury, the majority of trace elements are well controlled due to their association with the particulate phase of flue gas. Reflecting the current focus of the US EPA and state environmental agencies on mercury as a potential candidate for regulation, the project specifically targets the measurement and control of mercury species. This paper discusses the results of testing on the quantity and species distribution of mercury while firing Ohio high-sulfur coal to assess the mercury emissions control potential of conventional SO 2 and particulate control systems. Results from recent AECDP tests are presented and two alternative mercury speciation methods are compared. The AECDP results clearly show that higher total mercury control efficiency can be achieved with a wet FGD scrubber than recently reported in the interim final US EPA report on HAP emissions from fossil-fired electric utility steam generating units

AGS Spallation Target Experiment (ASTE) Collaboration

International Nuclear Information System (INIS)

Oyama, Yukio

1999-01-01

An experiment on mercury spallation target with high energy proton beam, called as the AGS Spallation Target Experiment (ASTE) Collaboration, has been performed at Alternating Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL) in USA, in cooperation among the laboratories in Japan, Europe and USA. The experimental setup, scope and preliminary results are presented in the paper. (author)

Mercury contamination in Khramulia (Capoeta capoeta) from the Cheshme Kile and Zarrin Gol Rivers in Iran and human health risk assessment.

Science.gov (United States)

Malvandi, Hassan; Sari, Abbas Esmaili; Aliabadian, Mansour

2014-10-01

Total mercury concentrations were determined in muscle tissue of Khramulia (Capoeta capoeta) captured in the Cheshme Kile and Zarrin Gol Rivers, Iran. In Cheshme Kile River, 49 fish samples were collected. The mean total mercury concentration in the muscles of C. capoeta from this area was 249 ng g(-1) dw. In Zarrin Gol River, where 62 fish samples were collected, the total mercury in muscles averaged 164 ng g(-1) dw. A significant difference was found between means of mercury in the rivers (p rivers had mean mercury concentrations below the maximum allowable limits for mercury set by the Food and Agriculture Organization, World Health Organization, Standardization Administration of China and Environmental Protection Agency. The results of this study indicate that the values of hazard target quotient and estimated weekly intake are low and represent a negligible risk for human health.

Mercury pollution in Malaysia.

Science.gov (United States)

Hajeb, Parvaneh; Jinap, S; Ismail, Ahmad; Mahyudin, Nor Ainy

2012-01-01

Although several studies have been published on levels of mercury contamination of the environment, and of food and human tissues in Peninsular Malaysia, there is a serious dearth of research that has been performed in East Malaysia (Sabah and Sarawak). Industry is rapidly developing in East Malaysia, and, hence, there is a need for establishing baseline levels of mercury contamination in environmental media in that part of the country by performing monitoring studies. Residues of total mercury and inorganic in food samples have been determined in nearly all previous studies that have been conducted; however, few researchers have analyzed samples for the presence of methlymercury residues. Because methylmercury is the most toxic form of mercury, and because there is a growing public awareness of the risk posed by methylmercury exposure that is associated with fish and seafood consumption, further monitoring studies on methylmercury in food are also essential. From the results of previous studies, it is obvious that the economic development in Malaysia, in recent years, has affected the aquatic environment of the country. Primary areas of environmental concern are centered on the rivers of the west Peninsular Malaysian coast, and the coastal waters of the Straits of Malacca, wherein industrial activities are rapidly expanding. The sources of existing mercury input to both of these areas of Malaysia should be studied and identified. Considering the high levels of mercury that now exists in human tissues, efforts should be continued, and accelerated in the future, if possible, to monitor mercury contamination levels in the coastal states, and particularly along the west Peninsular Malaysian coast. Most studies that have been carried out on mercury residues in environmental samples are dated, having been conducted 20-30 years ago; therefore, the need to collect much more and more current data is urgent. Furthermore, establishing baseline levels of mercury exposure to

Mercury Information Clearinghouse

Energy Technology Data Exchange (ETDEWEB)

Chad A. Wocken; Michael J. Holmes; Dennis L. Laudal; Debra F. Pflughoeft-Hassett; Greg F. Weber; Nicholas V. C. Ralston; Stanley J. Miller; Grant E. Dunham; Edwin S. Olson; Laura J. Raymond; John H. Pavlish; Everett A. Sondreal; Steven A. Benson

2006-03-31

The Canadian Electricity Association (CEA) identified a need and contracted the Energy & Environmental Research Center (EERC) to create and maintain an information clearinghouse on global research and development activities related to mercury emissions from coal-fired electric utilities. With the support of CEA, the Center for Air Toxic Metals{reg_sign} (CATM{reg_sign}) Affiliates, and the U.S. Department of Energy (DOE), the EERC developed comprehensive quarterly information updates that provide a detailed assessment of developments in the various areas of mercury monitoring, control, policy, and research. A total of eight topical reports were completed and are summarized and updated in this final CEA quarterly report. The original quarterly reports can be viewed at the CEA Web site (www.ceamercuryprogram.ca). In addition to a comprehensive update of previous mercury-related topics, a review of results from the CEA Mercury Program is provided. Members of Canada's coal-fired electricity generation sector (ATCO Power, EPCOR, Manitoba Hydro, New Brunswick Power, Nova Scotia Power Inc., Ontario Power Generation, SaskPower, and TransAlta) and CEA, have compiled an extensive database of information from stack-, coal-, and ash-sampling activities. Data from this effort are also available at the CEA Web site and have provided critical information for establishing and reviewing a mercury standard for Canada that is protective of environment and public health and is cost-effective. Specific goals outlined for the CEA mercury program included the following: (1) Improve emission inventories and develop management options through an intensive 2-year coal-, ash-, and stack-sampling program; (2) Promote effective stack testing through the development of guidance material and the support of on-site training on the Ontario Hydro method for employees, government representatives, and contractors on an as-needed basis; (3) Strengthen laboratory analytical capabilities through

A high-power target experiment

CERN Document Server

Kirk, H G; Ludewig, H; Palmer, Robert; Samulyak, V; Simos, N; Tsang, Thomas; Bradshaw, T W; Drumm, Paul V; Edgecock, T R; Ivanyushenkov, Yury; Bennett, Roger; Efthymiopoulos, Ilias; Fabich, Adrian; Haseroth, H; Haug, F; Lettry, Jacques; Hayato, Y; Yoshimura, Koji; Gabriel, Tony A; Graves, Van; Spampinato, P; Haines, John; McDonald, Kirk T

2005-01-01

We describe an experiment designed as a proof-of-principle test for a target system capable of converting a 4 MW proton beam into a high-intensity muon beam suitable for incorporation into either a neutrino factory complex or a muon collider. The target system is based on exposing a free mercury jet to an intense proton beam in the presence of a high strength solenoidal field.

46 CFR 199.176 - Markings on lifesaving appliances.

Science.gov (United States)

2010-10-01

... ARRANGEMENTS LIFESAVING SYSTEMS FOR CERTAIN INSPECTED VESSELS Requirements for All Vessels § 199.176 Markings on lifesaving appliances. (a) Lifeboats and rescue boats. Each lifeboat and rescue boat must be plainly marked as follows: (1) Each side of each lifeboat and rescue boat bow must be marked in block...

Mercury recycling in the United States in 2000

Science.gov (United States)

Brooks, William E.; Matos, Grecia R.

2005-01-01

Reclamation and recycling of mercury from used mercury- containing products and treatment of byproduct mercury from gold mining is vital to the continued, though declining, use of this metal. Mercury is reclaimed from mercury-containing waste by treatment in multistep high-temperature retorts-the mercury is volatized and then condensed for purification and sale. Some mercury-containing waste, however, may be landfilled, and landfilled material represents loss of a recyclable resource and a threat to the environment. Related issues include mercury disposal and waste management, toxicity and human health, and regulation of mercury releases in the environment. End-users of mercury-containing products may face fines and prosecution if these products are improperly recycled or not recycled. Local and State environmental regulations require adherence to the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation, and Liability Act to regulate generation, treatment, and disposal of mercury-containing products. In the United States, several large companies and a number of smaller companies collect these products from a variety of sources and then reclaim and recycle the mercury. Because mercury has not been mined as a principal product in the United States since 1992, mercury reclamation from fabricated products has become the main source of mercury. Principal product mercury and byproduct mercury from mining operations are considered to be primary materials. Mercury may also be obtained as a byproduct from domestic or foreign gold-processing operations. In the early 1990s, U.S. manufacturers used an annual average that ranged from 500 to 600 metric tons of recycled and imported mercury for fabrication of automobile convenience switches, dental amalgam, fluorescent lamps, medical uses and thermometers, and thermostats. The amount now used for fabrication is estimated to be 200 metric tons per year or less. Much of the data on

Quarter 9 Mercury information clearinghouse final report

Energy Technology Data Exchange (ETDEWEB)

Laudal, D.L.; Miller, S.; Pflughoeft-Hassett, D.; Ralston, N.; Dunham, G.; Weber, G.

2005-12-15

The Canadian Electricity Association (CEA) identified a need and contracted the Energy & Environmental Research Center (EERC) to create and maintain an information clearinghouse on global research and development activities related to mercury emissions from coal-fired electric utilities. A total of eight reports were completed and are summarized and updated in this final CEA quarterly report. Selected topics were discussed in detail in each quarterly report. Issues related to mercury from coal-fired utilities include the general areas of measurement, control, policy, and transformations. Specific topics that have been addressed in previous quarterly reports include the following: Quarterly 1 - Sorbent Control Technologies for Mercury Control; Quarterly 2 - Mercury Measurement; Quarterly 3 - Advanced and Developmental Mercury Control Technologies; Quarterly 4 - Prerelease of Mercury from Coal Combustion By-Products; Quarterly 5 - Mercury Fundamentals; Quarterly 6 - Mercury Control Field Demonstrations; Quarterly 7 - Mercury Regulations in the United States: Federal and State; and Quarterly 8 - Commercialization Aspects of Sorbent Injection Technologies in Canada. In this last of nine quarterly reports, an update of these mercury issues is presented that includes a summary of each topic, with recent information pertinent to advances made since the quarterly reports were originally presented. In addition to a comprehensive update of previous mercury-related topics, a review of results from the CEA Mercury Program is provided. 86 refs., 11 figs., 8 tabs.

Phytoremediation of Ionic and Methyl Mercury Pollution

Energy Technology Data Exchange (ETDEWEB)

Meagher, Richard B.

2005-06-01

Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

Minamata Convention on Mercury

Science.gov (United States)

On November 6, 2013 the United States signed the Minamata Convention on Mercury, a new multilateral environmental agreement that addresses specific human activities which are contributing to widespread mercury pollution

Intake of mercury through fish consumption

International Nuclear Information System (INIS)

Sarmani, S.B.; Kiprawi, A.Z.; Ismail, R.B.; Hassan, R.B.; Wood, A.K.; Rahman, S.A.

1995-01-01

Fish has been known as a source of non-occupational mercury exposure to fish consuming population groups, and this is shown by the high hair mercury levels. In this study, hair samples collected from fishermen and their families, and commercial marine fishes were analyzed for mercury and methylmercury by neutron activation and gas chromatography. The results showed a correlation between hair mercury levels and fish consumption patterns. The levels of mercury found in this study were similar to those reported by other workers for fish consuming population groups worldwide. (author)

Total Mercury content of skin toning creams

African Journals Online (AJOL)

Administrator

2008-04-01

Apr 1, 2008 ... used it for cosmetics (Silberberg, 1995). Mercury- ... Cosmetic preparations containing mercury com- pounds are .... mercury determination by a modified version of an open .... level mercury exposure, which could lead to a.

Can preoperative CEA and CA19-9 serum concentrations suggest metastatic disease in colorectal cancer patients?

Science.gov (United States)

Stojkovic Lalosevic, Milica; Stankovic, Sanja; Stojkovic, Mirjana; Markovic, Velimir; Dimitrijevic, Ivan; Lalosevic, Jovan; Petrovic, Jelena; Brankovic, Marija; Pavlovic Markovic, Aleksandra; Krivokapic, Zoran

2017-01-01

This study was designed to investigate the efficiency of preoperative serum carcinoembryonic antigen (CEA) and carbohydrate cancer antigen (CA19-9) levels for diagnosing synchronous liver metastases and lymph node in colorectal carcinoma (CRC) patients. A total of 300 patients with histologically diagnosed CRC were included in this study between May 2014 and March 2015. The data were obtained prospectively from patient's medical records: medical history, demographics, tumor location, differentiation (grade), depth of the tumor (T), lymph node metastases (N), distant metastases (M), lymphatics, venous and perineural invasion, and disease stage. Tumor markers were measured with an electrochemiluminescent assay and the reference value was 5ng/ml for CEA and for Ca19-9, 37u/ml. There was A high statistically significant difference in the levels of serum CEA and CA19-9 between different disease stages of CRC (PCEA (stage I 3.76±8.73; II 5.68±17.27, III 7.56±14.81, and IV 70.90±253.23) and CA 19-9 levels (stage I 9.65±11.03, II 9.83±11.09; III 19.58±36.91, and IV 228.9±985.38, respectively). The mean CEA and CA19-9 serum levels were significantly higher in patients with regional lymph nodes involvement (CEA 37.21±177.85 vs 4.79±9.90, CA19-9 119.51±687.71 VS 12.24±17.69, respectively, PCEA 86.56±277.65 vs. 5.98±12.98, and CA19-9 273.27±1073.46 vs. 4.98±3142, respectively, with PCEA and CA 19-9, 3.5 ng/mL and 7.5 U/mL, respectively. While, a cut-off value for the presence of synchronous liver metastases of these two markers was 3.5ng/mL AND 5.5 U/mL. Our study showed that tumor makers, CEA and CA19-9, can be used as diagnostic factors regarding the severity of CRC specifically to suggest metastatic disease in CRC.

Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish.

Science.gov (United States)

Ackerman, Joshua T; Kraus, Tamara E C; Fleck, Jacob A; Krabbenhoft, David P; Horwath, William R; Bachand, Sandra M; Herzog, Mark P; Hartman, C Alex; Bachand, Philip A M

2015-05-19

Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California's Sacramento-San Joaquin Delta, stocked them with mosquitofish (Gambusia affinis), and then continuously applied agricultural drainage water that was either untreated (control), or treated with polyaluminum chloride or ferric sulfate coagulants. Total mercury and methylmercury concentrations in surface waters were decreased by 62% and 63% in polyaluminum chloride treated wetlands and 50% and 76% in ferric sulfate treated wetlands compared to control wetlands. Specifically, following coagulation, mercury was transferred from the filtered fraction of water into the particulate fraction of water which then settled within the wetland. Mosquitofish mercury concentrations were decreased by 35% in ferric sulfate treated wetlands compared to control wetlands. There was no reduction in mosquitofish mercury concentrations within the polyaluminum chloride treated wetlands, which may have been caused by production of bioavailable methylmercury within those wetlands. Coagulation may be an effective management strategy for reducing mercury contamination within wetlands, but further studies should explore potential effects on wetland ecosystems.

Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish

Science.gov (United States)

Ackerman, Joshua T.; Kraus, Tamara E.C.; Fleck, Jacob A.; Krabbenhoft, David P.; Horwarth, William R.; Bachand, Sandra M.; Herzog, Mark; Hartman, Christopher; Bachand, Philip A.M.

2015-01-01

Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California’s Sacramento–San Joaquin Delta, stocked them with mosquitofish (Gambusia affinis), and then continuously applied agricultural drainage water that was either untreated (control), or treated with polyaluminum chloride or ferric sulfate coagulants. Total mercury and methylmercury concentrations in surface waters were decreased by 62% and 63% in polyaluminum chloride treated wetlands and 50% and 76% in ferric sulfate treated wetlands compared to control wetlands. Specifically, following coagulation, mercury was transferred from the filtered fraction of water into the particulate fraction of water which then settled within the wetland. Mosquitofish mercury concentrations were decreased by 35% in ferric sulfate treated wetlands compared to control wetlands. There was no reduction in mosquitofish mercury concentrations within the polyaluminum chloride treated wetlands, which may have been caused by production of bioavailable methylmercury within those wetlands. Coagulation may be an effective management strategy for reducing mercury contamination within wetlands, but further studies should explore potential effects on wetland ecosystems.

Determination of mercury in plant material

Energy Technology Data Exchange (ETDEWEB)

Pickard, J A; Martin, J T

1960-07-01

An analytical procedure used for the determination of traces of mercury in plant material is described. The conditions of combustion of organic matter are controlled to avoid loss of mercury and EDTA is used to reduce the values for apparent mercury on uncontaminated samples. Satisfactory recoveries of mercury added to apples, tomatoes and coffee are obtained. 10 references, 1 table.

[Mercury Distribution Characteristics and Atmospheric Mercury Emission Factors of Typical Waste Incineration Plants in Chongqing].

Science.gov (United States)

Duan, Zhen-ya; Su, Hai-tao; Wang, Feng-yang; Zhang, Lei; Wang, Shu-xiao; Yu, Bin

2016-02-15

Waste incineration is one of the important atmospheric mercury emission sources. The aim of this article is to explore the atmospheric mercury pollution level of waste incineration industry from Chongqing. This study investigated the mercury emissions from a municipal solid waste incineration plant and a medical waste incineration plant in Chongqing. The exhaust gas samples in these two incineration plants were obtained using USA EPA 30B method. The mercury concentrations in the fly ash and bottom ash samples were analyzed. The results indicated that the mercury concentrations of the municipal solid waste and medical waste incineration plant in Chongqing were (26.4 +/- 22.7) microg x m(-3) and (3.1 +/- 0.8) microg x m(-3) in exhaust gas respectively, (5279.2 +/- 798.0) microg x kg(-1) and (11,709.5 +/- 460.5) microg x kg(-1) in fly ash respectively. Besides, the distribution proportions of the mercury content from municipal solid waste and medical waste in exhaust gas, fly ash, and bottom ash were 34.0%, 65.3%, 0.7% and 32.3%, 67.5%, 0.2% respectively; The mercury removal efficiencies of municipal solid waste and medical waste incineration plants were 66.0% and 67.7% respectively. The atmospheric mercury emission factors of municipal solid waste and medical waste incineration plants were (126.7 +/- 109.0) microg x kg(-1) and (46.5 +/- 12.0) microg x kg(-1) respectively. Compared with domestic municipal solid waste incineration plants in the Pearl River Delta region, the atmospheric mercury emission factor of municipal solid waste incineration plant in Chongqing was lower.

The mixed waste focus area mercury working group: an integrated approach for mercury treatment and disposal

International Nuclear Information System (INIS)

Conley, T.B.; Morris, M.I.; Holmes-Burns, H.; Petersell, J.; Schwendiman, L.

1997-01-01

In May 1996, the U.S. Department of Energy (DOE) Mixed Waste Focus Area (MWFA) initiated the Mercury Work Group (HgWG), which was established to address and resolve the issues associated with mercury- contaminated mixed wastes. Three of the first four technology deficiencies identified during the MWFA technical baseline development process were related to mercury amalgamation, stabilization, and separation/removal. The HgWG will assist the MWFA in soliciting, identifying, initiating, and managing all the efforts required to address these deficiencies. The focus of the HgWG is to better establish the mercury-related treatment needs at the DOE sites, refine the MWFA technical baseline as it relates to mercury treatment, and make recommendations to the MWFA on how to most effectively address these needs. The team will initially focus on the sites with the most mercury-contaminated mixed wastes, whose representatives comprise the HgWG. However, the group will also work with the sites with less inventory to maximize the effectiveness of these efforts in addressing the mercury- related needs throughout the entire complex

Atmospheric mercury footprints of nations.

Science.gov (United States)

Liang, Sai; Wang, Yafei; Cinnirella, Sergio; Pirrone, Nicola

2015-03-17

The Minamata Convention was established to protect humans and the natural environment from the adverse effects of mercury emissions. A cogent assessment of mercury emissions is required to help implement the Minamata Convention. Here, we use an environmentally extended multi-regional input-output model to calculate atmospheric mercury footprints of nations based on upstream production (meaning direct emissions from the production activities of a nation), downstream production (meaning both direct and indirect emissions caused by the production activities of a nation), and consumption (meaning both direct and indirect emissions caused by final consumption of goods and services in a nation). Results show that nations function differently within global supply chains. Developed nations usually have larger consumption-based emissions than up- and downstream production-based emissions. India, South Korea, and Taiwan have larger downstream production-based emissions than their upstream production- and consumption-based emissions. Developed nations (e.g., United States, Japan, and Germany) are in part responsible for mercury emissions of developing nations (e.g., China, India, and Indonesia). Our findings indicate that global mercury abatement should focus on multiple stages of global supply chains. We propose three initiatives for global mercury abatement, comprising the establishment of mercury control technologies of upstream producers, productivity improvement of downstream producers, and behavior optimization of final consumers.

Evaluation of clinical value of serum CA19-9

International Nuclear Information System (INIS)

Lv Haifeng; Lin Zhiyu; Lu Xiaozhuo; Chen Yini

2003-01-01

The article is to study the clinical significance of serum CA19-9 in diagnosing malignant tumor occurred in digestive system and to select cut off values for differentiating diagnosis of a pancreatic neoplasms and pancreatitis. Using chemiluminescence immunoassay, serum CA19-9 level of below subjects were analyzed: control group (n=21); digestive system neoplasm group (n=125, with 7 cases conformed as pancreatic cancer); non-neoplastic disease group (n=387, with 15 cases conformed as pancreatitis secondary to destructive cholangitis). Receiver operating characteristic (ROC) curve was used for analyzing results and selecting cut off values. When cut off value was 18.4 kU/L, sensibility for conforming a digestive system neoplasm was 60.8%, while its related specificity against control group and non-neoplastic disease group was 95. 2% and 68.2%, respectively. Sensibility for diagnosing pancreatic neoplasm was 85.7%, while its related specificity against control group and non-pancreatic origin tumor group was 95.0% and 63.1%, respectively. When 37 kU/L was chosen as cut off value, specificity for differentiating diagnosis of pancreatic neoplasm and pancreatitis secondary to destructive cholangitis rose from 13.3% to 46.7%. Serum CA19-9 could be used as an aid in detecting digestive system neoplastic disease; it is a reliable marker for pancreatic neoplasm. Raising cut off value may help to differentiate pancreatic neoplasm and pancreatitis secondary to destructive cholangitis

Does mercury vapor exposure increase urinary selenium excretion

Energy Technology Data Exchange (ETDEWEB)

Hongo, T; Suzuki, T; Himeno, S; Watanabe, C; Satoh, H; Shimada, Y

1985-01-01

It has been reported that an increase of urinary selenium excretion may occur as a result of mercury vapor exposure. However, experimental data regarding the interaction between mercury vapor and selenium have yielded ambiguous results about the retention and elimination of selenium due to mercury vapor exposure and the decrease of selenium excretion due to mercury in the form of mercuric mercury (Hg/sup 2 +/). In this study, the authors measured urinary mercury and selenium in workers with or without exposure to mercury vapor to determine whether or not urinary selenium excretion was increased as a result of mercury vapor exposure. Urine samples were collected from 141 workers, 71 men and 70 women, whose extent of exposure to mercury vapor varied according to their job sites. Workers were divided into five groups according to their urinary mercury levels. The mercury level in group I was less than 2.8 nmol/mmol creatinine which means that this group was mostly free from mercury exposure. The average age was almost identical among the groups. For both sexes, group V (with the highest urinary mercury level) had the lowest urinary selenium level, but one-way variance analysis (ANOVA) did not reveal any significant variations of urinary selenium with urinary mercury levels; however, a weak but significant negative correlation between mercury and selenium was found in men.

Isolation, screening and identification of mercury resistant bacteria from mercury contaminated soil

Directory of Open Access Journals (Sweden)

Kowalczyk Anna

2016-01-01

Full Text Available New bacterial strains resistant to high concentration of mercury were obtained and character iz ed focusing on their potential application in bioremediation. The biological material was isolated from soil contaminated with mercury. The ability to removal of Hg from the liquid medium and the effect of the various pH and mercury concentrations in the environment on bacterial strains growth kinetics were tested. The selected strains were identified by analysis of the 16S ribosome subunit coding sequenc es as Pseudomonas syringae. The analysis of Hg concentration in liquid medium as effect of microbial metabolism demonstrated that P. syringae is able to remove almost entire metal from medium after 120 hours of incubation. Obtained results revealed new ability of the isolated strain P. syringae. Analyzed properties of this soil bacteria species able to reduce concentration of Hg ors immobi lize this metal are promising for industrial wastewater treatment and bioremediation of the soils polluted especially by mercury lamps scrapping, measuring instruments, dry batteries, detonators or burning fuels made from crude oil, which may also contain mercury. Selected bacteria strains provide efficient and relatively low-cost bioremediation of the areas and waters contaminated with Hg.

Comparison of circulating MMP-9, TIMP-1 and CA19-9 in the detection of pancreatic cancer

DEFF Research Database (Denmark)

Jørgensen, Maiken Thyregod; Brunner, Nils; Schaffalitzky de Muckadell, Ove B.

2010-01-01

, TIMP-1 and CA19-9 in detecting pancreatic ductal adenocarcinoma were 58.82%, 47.1% and 86%, respectively, with specificities of 34.6%, 69.2% and 73%. The AUCs of MMP-9, TIMP-1 and CA19-9 were 0.50, 0.64 and 0.84, respectively. Combining the three markers did not significantly improve detection......Background/Aim: The performance of the circulating tumor markers carbohydrate antigen 19-9 (CA19-9), matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) were evaluated separately and in combination for their potential value in detecting pancreatic ductal...... adenocarcinoma. PATIENTS AND METHODS: The patients had symptoms of pancreatic cancer. The discriminative strength of MMP-9 and TIMP-1 were compared to that of CA19-9 using receiver operating characteristics curves, area under the curves (AUC), specificity and sensitivity. RESULTS: The sensitivities of MMP-9...

Occupational Metallic Mercury Poisoning in Gilders

Directory of Open Access Journals (Sweden)

M Vahabzadeh

2016-04-01

Full Text Available Occupational exposure to elemental mercury vapor usually occurs through inhalation during its utilizations. This leads to a variety of adverse health effects. In some Islamic cities, this type of poisoning may occur during gilding of shrines using elemental mercury with gold. Herein, we report on three male patients aged 20–53 years, who were diagnosed with occupational metallic mercury poisoning due to gilding of a shrine. All patients presented with neuro-psychiatric disorders such as anxiety, loss of memory and concentration, and sleep disorders with high urinary mercury concentrations of 326–760 μg/L upon referring, 3–10 days after cessation of elemental mercury exposure. Following chelating therapy, the patients recovered clinically and their mercury concentrations declined to non-toxic level (<25 μg/L. Health, environmental and labor authorities, as well as the gilders should be aware of the toxicity risk of exposure to metalic mercury during gilding in closed environments and act accordingly.

Sexual differences in the distribution and retention of organic and inorganic mercury in methyl mercury-treated rats

International Nuclear Information System (INIS)

Thomas, D.J.; Fisher, H.L.; Sumler, M.R.; Marcus, A.H.; Mushak, P.; Hall, L.L.

1986-01-01

At 56 days of age, male and female Long-Evans rats received 1 μmole of 203 Hg-labeled mercuric chloride per kilogram sc and total, organic, and inorganic mercury contents and concentrations in tissues were determined for up to 98 days postdosing. When expressed on a concentration basis, the only significant sexual difference was in the higher average concentration of organic mercury in the kidneys of females. When expressed on a tissue content basis, significant male-female differences in the kinetics (sex x time interactions) of organic mercury retention were found in kidney, brain, skeletal muscle, pelt, and whole body. Significant sex x time interactions in the concentrations of organic mercury were found in kidney, skeletal muscle, and whole body. Kinetics of retention and concentration of inorganic Hg in the pelt differed significantly for males and females. Discordance of degree of statistical significance of differences in mercury contents and concentrations reflected in part differences in relative body composition of males and females. Differences in integrated exposure were estimated by the female-to-male ratio of areas under retention curves. Reconstruction of whole body organic and inorganic mercury burdens from constituent tissues indicated that integrated exposures of males and females to inorganic mercury were equal but females had a lower integrated exposure to organic mercury. Integrated exposure of liver to either form of mercury was about equal in males and females. However, the integrated exposure of the brain of females to inorganic mercury was 2.19 times that of males suggest'ing a sexual difference in accumulation or retention of inorganic mercury in the nervous system

49 CFR 40.199 - What problems always cause a drug test to be cancelled?

Science.gov (United States)

2010-10-01

... cancelled? 40.199 Section 40.199 Transportation Office of the Secretary of Transportation PROCEDURES FOR... cause a drug test to be cancelled? (a) As the MRO, when the laboratory discovers a “fatal flaw” during... specimen has been “Rejected for Testing” (with the reason stated). You must always cancel such a test. (b...

Target-induced formation of gold amalgamation on DNA-based sensing platform for electrochemical monitoring of mercury ion coupling with cycling signal amplification strategy

Energy Technology Data Exchange (ETDEWEB)

Chen, Jinfeng; Tang, Juan; Zhou, Jun; Zhang, Lan; Chen, Guonan; Tang, Dianping, E-mail: dianping.tang@fzu.edu.cn

2014-01-31

Graphical abstract: -- Highlights: •We report a new electrochemical sensing protocol for the detection of mercury ion. •Gold amalgamation on DNA-based sensing platform was used as nanocatalyst. •The signal was amplified by cycling signal amplification strategy. -- Abstract: Heavy metal ion pollution poses severe risks in human health and environmental pollutant, because of the likelihood of bioaccumulation and toxicity. Driven by the requirement to monitor trace-level mercury ion (Hg{sup 2+}), herein we construct a new DNA-based sensor for sensitive electrochemical monitoring of Hg{sup 2+} by coupling target-induced formation of gold amalgamation on DNA-based sensing platform with gold amalgamation-catalyzed cycling signal amplification strategy. The sensor was simply prepared by covalent conjugation of aminated poly-T{sub (25)} oligonucleotide onto the glassy carbon electrode by typical carbodiimide coupling. Upon introduction of target analyte, Hg{sup 2+} ion was intercalated into the DNA polyion complex membrane based on T–Hg{sup 2+}–T coordination chemistry. The chelated Hg{sup 2+} ion could induce the formation of gold amalgamation, which could catalyze the p-nitrophenol with the aid of NaBH{sub 4} and Ru(NH{sub 3}){sub 6}{sup 3+} for cycling signal amplification. Experimental results indicated that the electronic signal of our system increased with the increasing Hg{sup 2+} level in the sample, and has a detection limit of 0.02 nM with a dynamic range of up to 1000 nM Hg{sup 2+}. The strategy afforded exquisite selectivity for Hg{sup 2+} against other environmentally related metal ions. In addition, the methodology was evaluated for the analysis of Hg{sup 2+} in spiked tap-water samples, and the recovery was 87.9–113.8%.

Mercury cycling in a wastewater treatment plant treating waters with high mercury contents.

Science.gov (United States)

García-Noguero, Eva M.; García-Noguero, Carolina; Higueras, Pablo; Reyes-Bozo, Lorenzo; Esbrí, José M.

2015-04-01

The Almadén mercury mining district has been historically the most important producer of this element since Romans times to 2004, when both mining and metallurgic activities ceased as a consequence both of reserves exhaustion and persistent low prices for this metal. The reclamation of the main dump of the mine in 2007-2008 reduced drastically the atmospheric presence of the gaseous mercury pollutant in the local atmosphere. But still many areas, and in particular in the Almadén town area, can be considered as contaminated, and produce mercury releases that affect the urban residual waters. Two wastewater treatment plants (WWTP) where built in the area in year 2002, but in their design the projects did not considered the question of high mercury concentrations received as input from the town area. This communication presents data of mercury cycling in one of the WWTP, the Almadén-Chillón one, being the larger and receiving the higher Hg concentrations, due to the fact that it treats the waters coming from the West part of the town, in the immediate proximity to the mine area. Data were collected during a number of moments of activity of the plant, since April 2004 to nowadays. Analyses were carried out by means of cold vapor-atomic fluorescence spectroscopy (CV-AFS), using a PSA Millennium Merlin analytical device with gold trap. The detection limit is 0.1 ng/l. The calibration standards are prepared using the Panreac ICP Standard Mercury Solution (1,000±0,002 g/l Hg in HNO3 2-5%). Results of the surveys indicate that mercury concentrations in input and output waters in this plant has suffered an important descent since the cessation of mining and metallurgical activities, and minor reduction also after the reclamation of the main mine's dump. Since 2009, some minor seasonal variations are detected, in particular apparently related to accumulation during summer of mercury salts and particles, which are washed to the plant with the autumn's rains. Further

Maternal transfer of mercury to songbird eggs.

Science.gov (United States)

Ackerman, Joshua T; Hartman, C Alex; Herzog, Mark P

2017-11-01

We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers and collected their full clutches (n = 476 eggs) within 3 days of clutch completion. Additionally, we sampled blood and feathers from 53 tree swallow mothers and randomly collected one egg from their clutches (n = 53 eggs) during mid to late incubation (6-10 days incubated) to evaluate whether the relationship varied with the timing of sampling the mother's blood. Mercury concentrations in eggs were positively correlated with mercury concentrations in maternal blood sampled at (1) the time of clutch completion for both house wrens (R 2  = 0.97) and tree swallows (R 2  = 0.97) and (2) during mid to late incubation for tree swallows (R 2  = 0.71). The relationship between mercury concentrations in eggs and maternal blood did not differ with the stage of incubation when maternal blood was sampled. Importantly, the proportion of mercury transferred from mothers to their eggs decreased substantially with increasing blood mercury concentrations in tree swallows, but increased slightly with increasing blood mercury concentrations in house wrens. Additionally, the proportion of mercury transferred to eggs at the same maternal blood mercury concentration differed between species. Specifically, tree swallow mothers transferred 17%-107% more mercury to their eggs than house wren mothers over the observed mercury concentrations in maternal blood (0.15-1.92 μg/g ww). In contrast, mercury concentrations in eggs were not correlated with those in maternal feathers and, likewise, mercury concentrations in maternal blood were not correlated with those in feathers (all R 2  mercury concentrations from maternal blood to eggs

CA 19-9 Pancreatic Tumor Marker Fluorescence Immunosensing Detection via Immobilized Carbon Quantum Dots Conjugated Gold Nanocomposite.

Science.gov (United States)

Alarfaj, Nawal Ahmad; El-Tohamy, Maha Farouk; Oraby, Hesham Farouk

2018-04-11

The clinical detection of carbohydrate antigen 19-9 (CA 19-9), a tumor marker in biological samples, improves and facilitates the rapid screening and diagnosis of pancreatic cancer. A simple, low cost, fast, and green synthesis method to prepare a viable carbon quantum dots/gold (CQDs/Au) nanocomposite fluorescence immunosensing solution for the detection of CA 19-9 was reported. The present method is conducted by preparing glucose-derived CQDs using a microwave-assisted method. CQDs were employed as reducing and stabilizing agents for the preparation of a CQDs/Au nanocomposite. The immobilized anti-CA 19-9-labeled horseradish peroxidase enzyme (Ab-HRP) was anchored to the surface of a CQDs/Au nanocomposite by a peptide interaction between the carboxylic and amine active groups. The CA 19-9 antigen was trapped by another monoclonal antibody that was coated on the surface of microtiter wells. The formed sandwich capping antibody-antigen-antibody enzyme complex had tunable fluorescence properties that were detected under excitation and emission wavelengths of 420 and 530 nm. The increase in fluorescence intensities of the immunoassay sensing solution was proportional to the CA 19-9 antigen concentration in the linear range of 0.01-350 U mL -1 and had a lower detection limit of 0.007 U mL -1 . The proposed CQDs/Au nanocomposite immunoassay method provides a promising tool for detecting CA 19-9 in human serum.

Mercury in the environment : a primer

Energy Technology Data Exchange (ETDEWEB)

Lourie, B; Glenn, W [ed.; Ogilvie, K; Everhardus, E; Friesen, K; Rae, S

2003-06-01

This report provides an overview of the occurrence and effects of mercury in the environment and its impacts on human health. Low levels of mercury occur naturally everywhere in the environment in plants, animals, rocks and air. Incidental emissions occur when natural mercury is released to the environment through human activity. In Canada, coal burning and metal processing are the two largest point sources of atmospheric mercury emissions. Energy facilities have the option to invest in expensive control technologies for coal plants, or they can generate electricity from alternative energy sources. Energy conservation, however, offers the greatest overall benefits for the environment and the public. Mercury can also be released when products containing mercury (such as electrical switches, thermostats, dental amalgam, and thermometers) are broken while in use, or when they are crushed in garbage trucks and dumped in landfills. Source separation is the best way to reduce waste-related emissions. Once mercury is released to the natural environment, it can be transported long distances through air or watercourses. It is volatile, therefore evaporates readily to the atmosphere where it may do one of three things: it may fall out near the point where it was emitted; it may be transported long distances to some point downwind; or, it may enter the global atmospheric mercury pool where it will circle the globe for a year or more within the Earth's major weather systems before being deposited. Data from Canada's National Pollutant Release Inventory indicates that mercury releases and transfers total 28,674 kg per year. The most critical component of the mercury cycle is the conversion of inorganic forms of mercury to the organic compound methylmercury which is more toxic to humans. Most concern about mercury focuses on lakes and other aquatic ecosystems. Fish in hydroelectric reservoirs have been found to contain elevated methylmercury levels because natural mercury in the

Mercury Poisoning Linked to Skin Products

Science.gov (United States)

... Products For Consumers Home For Consumers Consumer Updates Mercury Poisoning Linked to Skin Products Share Tweet Linkedin ... and, in some situations, criminal prosecution. Dangers of Mercury Exposure to mercury can have serious health consequences. ...

Basic Information about Mercury

Science.gov (United States)

... or metallic mercury is a shiny, silver-white metal and is liquid at room temperature. It is ... releases can happen naturally. Both volcanoes and forest fires send mercury into the atmosphere. Human activities, however, ...

The fate of Mercury in Arctic regions: New understanding of atmospheric chemical processes and mercury stability in snow.

Science.gov (United States)

Steffen, A.; Ferrari, C.; Dommergue, A.; Scherz, T.; Lawson, G.; Leiatch, R.

2006-12-01

Mercury is a known toxic pollutant in the Arctic environment. Atmospheric mercury depletion events (AMDEs) have been studied in the Arctic since 1995. While advances in understanding this newly discovered cycling of mercury in the atmosphere have been made, much of the chemistry and the impact of this annually reoccurring event to the Arctic ecosystem are not well understood. Four years of continuous measurements at Alert, Canada of so-called reactive gaseous mercury (RGM) and mercury associated to particles (PHg) coupled with ongoing snow sampling have produced new information on the atmospheric chemistry and deposition of these mercury species to the Arctic. A distinct pattern during the springtime period in the distribution of these atmospheric mercury species has emerged. This pattern is characterized by the predominance of PHg concentration at the onset of the AMDEs. During the latter part of the AMDE season, there is an obvious swicth in the speciation of mercury to RGM as the main component during AMDEs. This swicth from PHg to RGM is clearly linked to a significant increase of mercury in the snow. In addition, concentrations of PHg are clearly linked with particles in the air that are primarily associated with Arctic haze. Recently, similar results have also been observed in Ny-Alesund (Svalbard). Further observations indicate that once deposited, the deposited mercury appears to evolve chemically in the snow. This change in mercury may impact the transfer of mercury to the environment during snow melt. These first time observed links between atmospheric conditions and subsequent deposition of mercury may help to ascertain the conditions throughout the Arctic as to when significant deposition of mercury will occur. It is proposed that should the concentration of atmospheric particles increase in the Arctic due to long range transport from emission sources, an increase in the deposition of mercury to this environment will increase during the springtime

Mercury

CERN Document Server

Mahoney, T J

2014-01-01

This gazetteer and atlas on Mercury lists, defines and illustrates every named (as opposed to merely catalogued) object and term as related to Mercury within a single reference work. It contains a glossary of terminology used, an index of all the headwords in the gazetteer, an atlas comprising maps and images with coordinate grids and labels identifying features listed in the gazetteer, and appendix material on the IAU nomenclature system and the transcription systems used for non-roman alphabets. This book is useful for the general reader, writers and editors dealing with astronomical themes, and those astronomers concerned with any aspect of astronomical nomenclature.

Mercury analysis in hair

DEFF Research Database (Denmark)

Esteban, Marta; Schindler, Birgit K; Jiménez-Guerrero, José A

2015-01-01

Human biomonitoring (HBM) is an effective tool for assessing actual exposure to chemicals that takes into account all routes of intake. Although hair analysis is considered to be an optimal biomarker for assessing mercury exposure, the lack of harmonization as regards sampling and analytical...... assurance program (QAP) for assessing mercury levels in hair samples from more than 1800 mother-child pairs recruited in 17 European countries. To ensure the comparability of the results, standard operating procedures (SOPs) for sampling and for mercury analysis were drafted and distributed to participating...... laboratories. Training sessions were organized for field workers and four external quality-assessment exercises (ICI/EQUAS), followed by the corresponding web conferences, were organized between March 2011 and February 2012. ICI/EQUAS used native hair samples at two mercury concentration ranges (0...

Coal fired flue gas mercury emission controls

International Nuclear Information System (INIS)

Wu, Jiang; Pan, Weiguo; Cao, Yan; Pan, Weiping

2015-01-01

Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of flue gas contents on the mercury speciation transformation process. Mercury emission control methods, such as existing APCDs (air pollution control devices) at power stations, sorbent injection, additives in coal combustion and photo-catalytic methods are introduced in detail. Lab-scale, pilot-scale and full-scale experimental studies of sorbent injection conducted by the authors are presented systematically, helping researchers and engineers to understand how this approach reduces the mercury emissions in flue gas and to apply the methods in mercury emission control at coal-fired power stations.

Coal fired flue gas mercury emission controls

Energy Technology Data Exchange (ETDEWEB)

Wu, Jiang; Pan, Weiguo [Shanghai Univ. of Electric Power (China); Cao, Yan; Pan, Weiping [Western Kentucky Univ., Bowling Green, KY (United States)

2015-05-01

Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of flue gas contents on the mercury speciation transformation process. Mercury emission control methods, such as existing APCDs (air pollution control devices) at power stations, sorbent injection, additives in coal combustion and photo-catalytic methods are introduced in detail. Lab-scale, pilot-scale and full-scale experimental studies of sorbent injection conducted by the authors are presented systematically, helping researchers and engineers to understand how this approach reduces the mercury emissions in flue gas and to apply the methods in mercury emission control at coal-fired power stations.

Flexible and Versatile as a Chameleon—Sophisticated Functions of microRNA-199a

Directory of Open Access Journals (Sweden)

Shen Gu

2012-07-01

Full Text Available Although widely studied in the past decade, our knowledge of the functional role of microRNAs (miRNAs remains limited. Among the many miRNAs identified in humans, we focus on miR-199a due to its varied and important functions in diverse models and systems. Its expression is finely regulated by promoter methylation and direct binding of transcription factors such as TWIST1. During tumorigenesis, depending on the nature of the cancer, miR-199a, especially its -3p mature form, may act as either a potential tumor suppressor or an oncogene. Its 5p mature form has been shown to protect cardiomyocytes from hypoxic damage via its action on HIF1α. It also has a functional role in stem cell differentiation, embryo development, hepatitis, liver fibrosis, etc. Though it has varied biological activities, its regulation has not been reviewed. The varied and protean functions of miR-199a suggest that efforts to generalize the action of a miRNA are problematic. This review provides a comprehensive survey of the literature on miR-199a as an example of the complexity of miRNA biology and suggests future directions for miRNA research.

Mercury emission monitoring on municipal waste combustion

International Nuclear Information System (INIS)

Braun, H.; Gerig, A.

1991-01-01

In waste incineration, mercury is the only heavy metal to be released as a gas, mostly as mercury(II) chloride, because of its high volatility. Continuous emission monitoring is possible only when mercury occurs in its elemental form. This paper reports on various possibilities of converting Hg(II) into Hg(0) that has been studied and tested on a laboratory scale and in the TAMARA refuse incineration pilot facility. Continuous mercury emission measurement appears to be possible, provided mercury is converted in the flue gas condensate precipitated. The measuring results obtained on two municipal solid waste and on one sewage treatment sludge incineration plants show that the mercury monitor is a highly sensitive and selective continuously working instrument for mercury emission monitoring

Mercury Spill Responses - Five States, 2012-2015.

Science.gov (United States)

Wozniak, Ryan J; Hirsch, Anne E; Bush, Christina R; Schmitz, Stuart; Wenzel, Jeff

2017-03-17

Despite measures to educate the public about the dangers of elemental mercury, spills continue to occur in homes, schools, health care facilities, and other settings, endangering the public's health and requiring costly cleanup. Mercury is most efficiently absorbed by the lungs, and exposure to high levels of mercury vapor after a release can cause cough, sore throat, shortness of breath, nausea, vomiting, diarrhea, headaches, and visual disturbances (1). Children and fetuses are most susceptible to the adverse effects of mercury vapor exposure. Because their organ systems are still developing, children have increased respiratory rates, and they are closer to the ground where mercury vapors are most highly concentrated (2). To summarize key features of recent mercury spills and lessons learned, five state health departments involved in the cleanup (Iowa, Michigan, Missouri, North Carolina, and Wisconsin) compiled data from various sources on nonthermometer mercury spills from 2012 to 2015. The most common sites of contamination were residences, schools and school buses, health care facilities, and commercial and industrial facilities. Children aged mercury exposure. To protect the public's health after a mercury spill, it is important that local, state, and federal agencies communicate and coordinate effectively to ensure a quick response, and to minimize the spread of contamination. To reduce the number of mercury spills that occur in the United States, public health officials should increase awareness about exchange programs for mercury-containing items and educate school and health care workers about sources of mercury and how to dispose of them properly.

Volcanic mercury in Pinus canariensis

Science.gov (United States)

Rodríguez Martín, José Antonio; Nanos, Nikos; Miranda, José Carlos; Carbonell, Gregoria; Gil, Luis

2013-08-01

Mercury (Hg) is a toxic element that is emitted to the atmosphere by both human activities and natural processes. Volcanic emissions are considered a natural source of mercury in the environment. In some cases, tree ring records taken close to volcanoes and their relation to volcanic activity over time are contradictory. In 1949, the Hoyo Negro volcano (La Palma-Canary Islands) produced significant pyroclastic flows that damaged the nearby stand of Pinus canariensis. Recently, 60 years after the eruption, we assessed mercury concentrations in the stem of a pine which survived volcano formation, located at a distance of 50 m from the crater. We show that Hg content in a wound caused by pyroclastic impacts (22.3 μg kg-1) is an order of magnitude higher than the Hg concentrations measured in the xylem before and after the eruption (2.3 μg kg-1). Thus, mercury emissions originating from the eruption remained only as a mark—in pyroclastic wounds—and can be considered a sporadic and very high mercury input that did not affect the overall Hg input in the xylem. In addition, mercury contents recorded in the phloem (9.5 μg kg-1) and bark (6.0 μg kg-1) suggest that mercury shifts towards non-living tissues of the pine, an aspect that can be related to detoxification in volcanism-adapted species.

Volcanic mercury in Pinus canariensis.

Science.gov (United States)

Rodríguez Martín, José Antonio; Nanos, Nikos; Miranda, José Carlos; Carbonell, Gregoria; Gil, Luis

2013-08-01

Mercury (Hg) is a toxic element that is emitted to the atmosphere by both human activities and natural processes. Volcanic emissions are considered a natural source of mercury in the environment. In some cases, tree ring records taken close to volcanoes and their relation to volcanic activity over time are contradictory. In 1949, the Hoyo Negro volcano (La Palma-Canary Islands) produced significant pyroclastic flows that damaged the nearby stand of Pinus canariensis. Recently, 60 years after the eruption, we assessed mercury concentrations in the stem of a pine which survived volcano formation, located at a distance of 50 m from the crater. We show that Hg content in a wound caused by pyroclastic impacts (22.3 μg kg(-1)) is an order of magnitude higher than the Hg concentrations measured in the xylem before and after the eruption (2.3 μg kg(-1)). Thus, mercury emissions originating from the eruption remained only as a mark-in pyroclastic wounds-and can be considered a sporadic and very high mercury input that did not affect the overall Hg input in the xylem. In addition, mercury contents recorded in the phloem (9.5 μg kg(-1)) and bark (6.0 μg kg(-1)) suggest that mercury shifts towards non-living tissues of the pine, an aspect that can be related to detoxification in volcanism-adapted species.

Dissolved gaseous mercury formation and mercury volatilization in intertidal sediments.

Science.gov (United States)

Cesário, Rute; Poissant, Laurier; Pilote, Martin; O'Driscoll, Nelson J; Mota, Ana M; Canário, João

2017-12-15

Intertidal sediments of Tagus estuary regularly experiences complex redistribution due to tidal forcing, which affects the cycling of mercury (Hg) between sediments and the water column. This study quantifies total mercury (Hg) and methylmercury (MMHg) concentrations and fluxes in a flooded mudflat as well as the effects on water-level fluctuations on the air-surface exchange of mercury. A fast increase in dissolved Hg and MMHg concentrations was observed in overlying water in the first 10min of inundation and corresponded to a decrease in pore waters, suggesting a rapid export of Hg and MMHg from sediments to the water column. Estimations of daily advective transport exceeded the predicted diffusive fluxes by 5 orders of magnitude. A fast increase in dissolved gaseous mercury (DGM) concentration was also observed in the first 20-30min of inundation (maximum of 40pg L -1 ). Suspended particulate matter (SPM) concentrations were inversely correlated with DGM concentrations. Dissolved Hg variation suggested that biotic DGM production in pore waters is a significant factor in addition to the photochemical reduction of Hg. Mercury volatilization (ranged from 1.1 to 3.3ngm -2 h -1 ; average of 2.1ngm -2 h -1 ) and DGM production exhibited the same pattern with no significant time-lag suggesting a fast release of the produced DGM. These results indicate that Hg sediment/water exchanges in the physical dominated estuaries can be underestimated when the tidal effect is not considered. Copyright © 2017 Elsevier B.V. All rights reserved.

Tumor markers CA19-9, CA242 and CEA in the diagnosis of pancreatic cancer: a meta-analysis.

Science.gov (United States)

Zhang, Yimin; Yang, Jun; Li, Hongjuan; Wu, Yihua; Zhang, Honghe; Chen, Wenhu

2015-01-01

Pancreatic cancer has the worst prognosis and early detection is crucial for improving patient prognosis. Therefore, we performed a meta-analysis to evaluate and compare the sensitivity and specificity of single test of CA19-9, CA242, and CEA, as well as combination test in pancreatic cancer detection. We searched PubMed, Embase, Medline, and Wanfang databases for studies that evaluated the diagnostic validity of CA19-9, CA242, and CEA between January 1990 and September 2014. Data were analyzed by Meta-Disc and STATA software. A total of 21 studies including 3497 participants, which fulfilled the inclusion criteria were considered for analysis. The pooled sensitivities for CA19-9, CA242, and CEA were 75.4 (95% CI: 73.4-77.4), 67.8 (95% CI: 65.5-70), and 39.5 (95% CI: 37.3-41.7), respectively. The pooled specificities of CA19-9, CA242, and CEA were 77.6 (95% CI: 75.4-79.7), 83 (95% CI: 81-85), and 81.3 (95% CI: 79.3-83.2), respectively. Parallel combination of CA19-9+CA242 has a higher sensitivity (89, 95% CI: 80-95) without impairing the specificity (75, 95% CI: 67-82). Our meta-analysis showed that CA242 and CA19-9 have better performance in the diagnosis of pancreatic cancer than CEA. Furthermore, parallel combination test of CA19-9+CA242 could be of better diagnostic value than individual CA242 or CA19-9 test.

CEA and CA 19-9 are still valuable markers for the prognosis of colorectal and gastric cancer patients.

Science.gov (United States)

Sisik, Abdullah; Kaya, Mustafa; Bas, Gurhan; Basak, Fatih; Alimoglu, Orhan

2013-01-01

The purpose of this study was to assess the predictive effect of preoperative CEA and CA 19-9 levels on the prognosis of colorectal and gastric cancer patients. CEA and CA 19-9 were evaluated preoperatively in patients undergoing surgery for colorectal cancer (n=116) and gastric cancer (n=49). Patients with CEA levels CEA Group 1, 5-30 ng/mL as CEA Group 2 and >30 ng/ mL were classified as CEA Group 3. Similarly the patients with a CA 19-9 level 100 U/mL as Group and 3. TNM stages and histologic grades were noted according to histopathological reports. Patients with a TNM grade 0 or 1 were classified as Group A, TNM grade 2 patients constituted Group B and TNM grade 3 and 4 patients constituted Group C. Demographic characteristics, tumor locations and blood types of the patients were all recorded and these data were compared with the preoperative CEA and CA19-9 values. A significant correlation between CA 19-9 levels (>100 U/mL) and TNM stage (in advanced stages) was determined. We also determined a significant correlation between TNM stages and positive vlaues for both CEA and CA 19-9 in colorectal and gastric cancer patients. In comparison between CEA and CA 19-9 levels and age, gender, tumor location, ABO blood group, and tumor histologic grade, no significant correlation was found. Positive levels of both CEA and CA 19-9 can be considered to indicate an advanced stage in colorectal and gastric cancer patients.

Mercury emissions from municipal solid waste combustors

Energy Technology Data Exchange (ETDEWEB)

1993-05-01

This report examines emissions of mercury (Hg) from municipal solid waste (MSW) combustion in the United States (US). It is projected that total annual nationwide MSW combustor emissions of mercury could decrease from about 97 tonnes (1989 baseline uncontrolled emissions) to less than about 4 tonnes in the year 2000. This represents approximately a 95 percent reduction in the amount of mercury emitted from combusted MSW compared to the 1989 mercury emissions baseline. The likelihood that routinely achievable mercury emissions removal efficiencies of about 80 percent or more can be assured; it is estimated that MSW combustors in the US could prove to be a comparatively minor source of mercury emissions after about 1995. This forecast assumes that diligent measures to control mercury emissions, such as via use of supplemental control technologies (e.g., carbon adsorption), are generally employed at that time. However, no present consensus was found that such emissions control measures can be implemented industry-wide in the US within this time frame. Although the availability of technology is apparently not a limiting factor, practical implementation of necessary control technology may be limited by administrative constraints and other considerations (e.g., planning, budgeting, regulatory compliance requirements, etc.). These projections assume that: (a) about 80 percent mercury emissions reduction control efficiency is achieved with air pollution control equipment likely to be employed by that time; (b) most cylinder-shaped mercury-zinc (CSMZ) batteries used in hospital applications can be prevented from being disposed into the MSW stream or are replaced with alternative batteries that do not contain mercury; and (c) either the amount of mercury used in fluorescent lamps is decreased to an industry-wide average of about 27 milligrams of mercury per lamp or extensive diversion from the MSW stream of fluorescent lamps that contain mercury is accomplished.

Mercury accumulation in native mammals of the Southeast

Energy Technology Data Exchange (ETDEWEB)

Cumbie, P.M.; Jenkins, J.H.

1974-01-01

Mercury levels in tissues of mammals collected in Georgia, Florida, and South Carolina were compared using hair mercury concentration as an index of total mercury content. Bobcats (Lynx rufus), raccoons (Procyon lotor), opossum (Didelphis marsupialis) and gray fox (Urocyon cinereoargenteus) from the Lower Coastal Plain of Georgia had higher mercury levels than specimens from the Upper Coastal Plain or Piedmont. The highest individual mercury levels in raccoons and bobcats occurred in specimens from the Georgia Lower Coastal Plain flatwoods. Skeletal muscle and liver of individual raccoons and bobcats taken in the coastal flatwoods exceeded the 0.5 ppm limit for mercury in human foodstuffs. No pattern of mercury accumulation was detected in white-tailed deer (Odocoileus virginianus). Hair analysis revealed elevated mercury levels in mammals from a region exposed to mercury pollution. Mercury levels in wildlife exhibit a pattern similar to that of certain fallout radioisotopes such as /sub 137/Cs. These observations indicate that significant biomagnification of mercury may occur in native mammals in certain southeastern habitats. 28 references, 6 tables.

Mercury in a coastal marine environment

Energy Technology Data Exchange (ETDEWEB)

Burton, J D; Leatherland, T M

1971-06-18

The problem of mercury pollution was investigated in Southampton Water and the English Channel. Mercury was determined in five specimens of the mollusk, Mercenaria mercenaria. The concentrations in whole organisms, without shell, ranged from 0.18 to 0.57 p.p.m. The amounts of mercury in the river and estuarine waters were found to be low. Yet, samples from the surface of the bottom mud in different parts of the estuary had mercury contents ranging from 0.19 to 0.64 p.p.m. The role of sediments in the transport of mercury in food chains could be significant, particularly for bottom living, suspension feeding animals. 14 references, 1 table.