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1.
Article in English | MEDLINE | ID: mdl-27898013

ABSTRACT

This study assessed the radiological health hazards to various body organs of workers working within Transnet Precinct in Richards Bay in Kwazulu-Natal, South Africa due to radionuclide content of mineral ores often stored within the facility. Thirty samples were collected from five mineral ores (rock phosphate, rutile, zircon, coal and hematite) and analyzed for 238U, 234U, 226Ra, 210Pb, 235U, 232Th, 228Ra, 228Th and 40K using delayed neutron activation analysis and low energy gamma spectroscopy. Rutile was found to be the most radioactive mineral ore within the facility with 210Pb concentration of 759.00 ± 106.00 Bq·kg-1. Effective annual dose rate in (mSv·y-1) delivered to different organs of the body: testes, bone marrow, whole body, lungs and ovaries from mineral ores were such that dose from mineral ores decreased in the order coal > rutile > rock phosphate > hematite > zircon. The organs with the highest received dose rate were the testes and this received dose was from coal. However, all of the calculated absorbed dose rates to organs of the body were below the maximum permissible safety limits.


Subject(s)
Radioisotopes/analysis , Soil Pollutants, Radioactive/analysis , Bays , Gamma Rays , Humans , Minerals/analysis , Radiation Dosage , Radiation Monitoring , South Africa
2.
Health Phys ; 94(5): 479-83, 2008 May.
Article in English | MEDLINE | ID: mdl-18403969

ABSTRACT

The Idaho Department of Environmental Quality INL Oversight Program (DEQ-INL) operates an environmental gamma radiation detection network consisting of a series of high-pressure ion chambers to provide real-time ambient radiation measurements and a series of passive environmental electret ion chambers to increase coverage area and measure cumulative dose over a calendar quarter. DEQ-INL has identified a consistent over-response of approximately 40% by the electret ion chambers with respect to co-located high-pressure ion chambers since 1998. DEQ-INL conducted a series of three investigations to quantify this over-response. The over-response is likely attributable to a number of factors, including inherent voltage loss by the electret material not due to ionization within the chamber. One aspect of the investigation verified the manufacturer's calibration factor used to convert decrease in voltage to exposure. Additional investigations were performed that identified an average electret voltage loss of 0.2 V d(-1). When this voltage correction was applied to historical environmental data, electret ion chamber response was within 10% of the co-located high-pressure ion chamber response.


Subject(s)
Environmental Monitoring/methods , Gamma Rays , Radiation Monitoring/methods , Calibration , Electric Capacitance , Electronics , Environmental Monitoring/instrumentation , Equipment Failure Analysis , Radiation Monitoring/instrumentation , Time Factors
3.
Health Phys ; 85(3): 348-56, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12938725

ABSTRACT

Atmospheric tritium monitoring involves the collection of tritiated water vapor by collecting atmospheric moisture from air that is drawn through a bed of desiccant material. This study is a comparison between molecular sieve and silica gel adsorbent media used for atmospheric moisture sampling conducted in the semi-arid climate of the Idaho National Engineering and Environmental Laboratory. Water vapor was collected simultaneously using two columns containing different desiccant materials (one column containing molecular sieve and the other containing silica gel). Data collected during air sampling periods were compared with meteorological data collected, and atmospheric moisture collection efficiencies were determined. Breakthrough of atmospheric moisture past the desiccant material was suspected with both media at elevated temperatures indicating that smaller sample volumes, lower volumetric flow rates, or longer adsorbent columns should be used during summer when ambient temperatures are elevated.


Subject(s)
Air Pollutants, Radioactive/analysis , Desiccation/instrumentation , Radiometry/instrumentation , Radiometry/methods , Tritium/analysis , Atmosphere/analysis , Desert Climate , Desiccation/methods , Environmental Monitoring/instrumentation , Environmental Monitoring/methods , Equipment Failure Analysis/methods , Idaho , Reproducibility of Results , Sensitivity and Specificity , Silicon Dioxide , Temperature , Water/analysis
4.
Health Phys ; 85(3): 371-6, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12938728

ABSTRACT

In 1999, the State of Idaho INEEL Oversight Program performed a field test to determine if electret ion chambers could be used as a replacement to soil sampling in field survey releases at a remediated radioactively contaminated site. This study compared exposure rates measured using electret ion chambers with gamma spectroscopic analysis results of soil samples collected at the remediated site. Exposure rate measurements were made in 1999 using electret ion chambers at the same locations that INEEL Oversight Program sampled soil in 1998 following MARSSIM protocol. The waste site was divided into nine survey units based upon site history including previous site surveys and physical boundaries. Exposure rate measurements at the remediation site compared well with exposure rate measurements made at reference background locations used for routine environmental monitoring by the State of Idaho indicating that the remedial action met cleanup criteria. A poor correlation between exposure rate measurements and 137Cs concentrations and other discrepancies were observed during this study with respect to measurements made during the 1998 final site survey.


Subject(s)
Environmental Monitoring/instrumentation , Radioactive Waste/analysis , Radiometry/instrumentation , Soil Pollutants, Radioactive/analysis , Biodegradation, Environmental , Electric Capacitance , Environmental Monitoring/methods , Equipment Failure Analysis/methods , Idaho , Ions , Radiation Dosage , Radiometry/methods , Reproducibility of Results , Sensitivity and Specificity
5.
Analyst ; 127(6): 748-54, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12146906

ABSTRACT

Acetyl gestagenic steroids are isolated from animal tissues such as bovine kidney fat by automated supercritical fluid extraction (SFE). After the addition of internal standards and sample pretreatment, the analytes are extracted from the matrix by supercritical CO2 and trapped directly in-line on alumina placed in the extraction vessel. The samples are analysed by liquid chromatography combined with ion-trap mass selective detection (LC-MSn). For quantification, deuterated internal standards are added and single ions of the analytes and internal standards are monitored. For confirmation of the identity of the analytes, two transition ions (one MS2 and one MS3) were monitored and the ratios between the ions were calculated and compared with those of standards. The detection capability for the multi-analyte LC-MSn analysis of megestrol acetate (MA), medroxyprogesterone acetate (MPA), chlormadinone acetate (CMA) and melengestrol acetate (MGA) is 0.5 microg kg(-1). The mean within-laboratory reproducibility ranges from 16-19% (%RSD) at a concentration level of 0.5 microg kg(-1) (n = 9). Running the SFE procedure overnight allows the analysis of 24 samples of fat per day.


Subject(s)
Drug Residues/analysis , Growth Substances/analysis , Kidney/chemistry , Melengestrol Acetate/analysis , Veterinary Drugs/analysis , Animals , Cattle , Drug and Narcotic Control
6.
Hum Factors ; 43(1): 1-11, 2001.
Article in English | MEDLINE | ID: mdl-11474755

ABSTRACT

In the crash involvement literature, it is generally assumed that archival and other "objective" criterion data are superior to self-reports of crash involvement. Using 394 participants (mean age = 36.23 years), the present study assessed the convergence of archival and self-report measures of motor vehicle crash involvement and moving violations. We also sought to determine whether predictor/criterion relationships would vary as a function of criterion type (i.e., archival vs. self-report), and if a combination of both criteria would result in better prediction than would either by itself. The degree of agreement between the two criterion sources was low, with participants self-reporting more crashes and tickets than were found in their state records. Different predictor/criterion relationships were also found for the two criterion types; stronger effects were obtained for self-report data. Combining the two criteria did not result in relationships stronger than those obtained for self-reports alone. Our findings suggest that self-report data are not inherently inferior to archival data and, furthermore, that the two sources of data cannot be used interchangeably. Actual or potential applications include choosing the appropriate criterion to use, which, as the finding of this study reveals, may depend on the purpose of the investigation.


Subject(s)
Accidents, Traffic/statistics & numerical data , Data Collection/statistics & numerical data , Accidents, Traffic/legislation & jurisprudence , Adult , Archives , Bias , Female , Humans , Male , Middle Aged , Self Disclosure , Texas
7.
J Consult Clin Psychol ; 68(5): 890-7, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11068975

ABSTRACT

This study examined whether witnessing death and injury could produce psychophysiologically responsive posttraumatic stress disorder (PTSD). Participants consisted of medication-free female Vietnam nurse veterans with a diagnosis of current PTSD (n = 17) and who never had PTSD (n = 21), related to their military service. Individualized scripts describing personal traumatic military nursing events, a standard military nursing event, and other life events were tape recorded and played back to the participant while heart rate, skin conductance, and facial electromyograms were recorded. Nurses with PTSD showed significantly larger physiologic responses than non-PTSD nurses only during imagery of military-related nursing events. The groups' self-reported emotional responses did not differ during imagery. Psychophysiologic results support the proposition that witnessing death and serious injury to others is sufficiently stressful to cause PTSD.


Subject(s)
Death , Imagery, Psychotherapy , Nurses/psychology , Stress Disorders, Post-Traumatic/physiopathology , Stress Disorders, Post-Traumatic/psychology , Veterans/psychology , Wounds and Injuries , Analysis of Variance , Case-Control Studies , Electromyography , Facial Muscles , Female , Galvanic Skin Response , Heart Rate , Humans , Mental Recall , Middle Aged , Stress Disorders, Post-Traumatic/etiology , Vietnam , Warfare
8.
J Appl Physiol (1985) ; 84(4): 1269-77, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9516193

ABSTRACT

We have previously documented the regional distribution of 70-kDa heat shock protein (HSP70) in brains of rats made hyperthermic by brief exposure to high-powered microwaves (HPM; 2.06 GHz). We now compare HSP70 expression induced by HPM exposure to that induced by exertional and/or environmental heat stress. Rats were chronically implanted with a temperature probe guide in the hypothalamic region of the brain (Tbr). After recovery, the following treatment groups were examined: HPM; sham exposed; treadmill exercise at room temperature (24 degreesC; Ex-1); treadmill exercise in a warm environment (34 degreesC; Ex-2); and sedentary groups (Sed-1 and Sed-2), in which ambient temperature was adjusted so that the Tbr mimicked the Tbr in the corresponding exercise groups. Significant HSP70 expression occurred only in the hyperthermic (Ex-2, Sed-2, and HPM) groups. The pattern of HSP70 expression was similar among Ex-2 and Sed-2 rats but differed from that in HPM rats. We conclude that 1) the pattern of HSP70 expression differs between HPM and nonmicrowave heating, and 2) exercise alone was not sufficient to induce central HSP70 expression.


Subject(s)
Central Nervous System/metabolism , HSP70 Heat-Shock Proteins/biosynthesis , Heat Exhaustion/physiopathology , Physical Exertion/physiology , Animals , Cell Nucleus/metabolism , Heat Exhaustion/metabolism , Immunohistochemistry , Male , Microwaves , Rats , Rats, Sprague-Dawley , Stereotaxic Techniques
9.
Health Phys ; 74(2): 237-41, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9450592

ABSTRACT

Factors potentially correlated with 222Rn concentrations in groundwater were evaluated using a database compiled by the U.S. Geological Survey. These included chemical and radiological factors, and both well depth and discharge rate. The 222Rn concentrations contained within this database were examined as a function of latitude and longitude. It was observed that the U.S. Geological Survey sample locations for 222Rn were not uniformly distributed throughout the state. Hence, additional samples were collected in southeastern Idaho, a region where few 222Rn in water analyses had been performed. 222Rn concentrations in groundwater, in Idaho, were found using ANOVA (alpha = 0.05) to be independent of the chemical, radiological, and well parameters thus far examined. This lack of correlation with other water quality and well parameters is consistent with findings in other geographical locations. It was observed that an inverse relationship between radon concentration and water hardness may exist.


Subject(s)
Fresh Water , Radon , Water Pollutants, Radioactive , Idaho , Temperature , Water Supply
10.
Eur J Anaesthesiol ; 5(1): 23-30, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3378553

ABSTRACT

Disagreement as to the effect of glycopyrrolate and atropine sulphate at various dosages on heart rate has been reported in the literature. Of particular interest is the question of whether small doses of glycopyrrolate cause bradycardia. Three groups of subjects were studied. The QRS complexes of the electrocardiogram were continuously recorded on a microcomputer. Group 1 consisted of 10 healthy volunteers who were given two doses of atropine sulphate 1.25 micrograms kg-1 and glycopyrrolate 0.75 micrograms kg-1, in random order at two different times, i.v. Monitoring continued until heart rate returned to baseline. Group 2 consisted of 24 women, ASA class I or II, scheduled for gynaecological operations. Each patient received fractionated i.v. doses of either atropine sulphate 2.5, 2.5 and 5 micrograms kg-1 or glycopyrrolate 1.5, 1.5 and 3.0 micrograms kg-1 at 3-min intervals. Heart rate was measured continuously for 1 h before drug injection and for 10 min after the last dose. Group 3 consisted of six volunteers given both drugs in the same dose and time schedule as Group 2, but heart rate was monitored for 180 min after the last dose. In Group 1, the incidence of bradycardia and increases in heart rate after the first dose were statistically significant for both atropine sulphate and glycopyrrolate when compared with baseline values. In Group 2, both drugs significantly increased the heart rate and had similar times to peak effect. In Group 3, bradycardia occurred only with atropine sulphate. Increases in heart rate, peak heart rate and duration of action were similar with both drugs.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Atropine/pharmacology , Glycopyrrolate/pharmacology , Heart Rate/drug effects , Pyrrolidines/pharmacology , Adult , Female , Humans , Male , Middle Aged
12.
J Immunol ; 124(5): 2063-70, 1980 May.
Article in English | MEDLINE | ID: mdl-6245133

ABSTRACT

We have investigated the minimal molecular requirements for T cell recognition of a previously described myeloma tumor (MOPC-315-EL), which reversibly alters its reactivity with T cells. Enucleation of MOPC-315 cells, either sensitive or resistant to reaction with T cells, did not alter the ability of the resulting cytoplasts to elicit or serve as targets for anti-H-2 or anti-Sendai viral cytotoxic T lymphocytes (CTL), despite the fact that there were no detectable differences in serologically defined H-2 or viral antigens on their surface. Likewise, when plasma membranes isolated from sensitive or resistant cells were tested for their ability to elicit anti-H-2 CTL, they retained the phenotype of the cells from which they were isolated. However, solubilized and partially purified H-2 antigens from both sensitive and resistant cells were able to elicit H-2-restricted anti-Sendai virus CTL when incorporated into liposomes with purified viral glycoproteins, and anti-H-2 CTL when incorporated alone into liposomes. These results suggest that a cellular surface component(s) exists that is probably not an H-2K or H-2D gene product and is responsible for the reversible variation in the reactivity of the tumor cells with T cells.


Subject(s)
Cytotoxicity, Immunologic , T-Lymphocytes/immunology , Animals , Antibodies, Viral , Cell Nucleus , Cytoplasm/immunology , Female , H-2 Antigens/immunology , Immune Sera/pharmacology , Liposomes/pharmacology , Male , Mice , Mice, Inbred A , Mice, Inbred BALB C , Mice, Inbred C57BL , Neoplasms, Experimental , Parainfluenza Virus 1, Human/immunology , Time Factors
15.
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