RESUMEN
In this study, two kinds of Artemisia plant, Artemisia campestris L. and Artemisia herba-alba Asso., collected from different locations in Djelfa province, Algeria, were subjected to an instrumental neutron activation analysis (INAA) in order to determine their essential and toxic elements for the first time. The obtained results for both types revealed the existence of twenty-one elements, namely, As, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Na, Rb, Sb, Sc, Sm, Sr, Yb, and Zn, where, the elements K, Ca, Fe, and Na respectively showed a significant concentration. On the other hand, the tolerable daily intake (TDI) of the studied plants for an adult person per day was within the tolerance limits imposed by the World Health Organization (WHO). Hence, these findings might therefore be used to offer scientific basis for an optimum usage of the studied plants and so enriches the database of medicinal herbs.
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Artemisia , Oligoelementos , Adulto , Argelia , Humanos , Análisis de Activación de Neutrones , Sodio , Oligoelementos/análisisRESUMEN
Alpha-particle spectrometry, gamma spectrometry and neutron activation analysis techniques for determination of Th and U in environmental samples have been compared. The analytical parameters studied include detection limit, accuracy, repeatability, reproducibility and surrogate recovery. The results show that neutron activation analysis technique has the best accuracy among the studied techniques; the other two techniques were assessed relative to it. The percentage difference between the three techniques results is about [-20, 20]. In addition, U and Th concentrations are generally overestimated by gamma spectrometry and alpha-particle spectrometry in all cases except Th concentration in the former technique, which is underestimated.
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Partículas alfa , Análisis de Activación de Neutrones/métodos , Contaminantes Radiactivos/análisis , Espectrometría gamma/métodos , Torio/análisis , Uranio/análisis , Límite de Detección , Monitoreo de Radiación/métodos , Radiometría/métodos , Reproducibilidad de los Resultados , SiriaRESUMEN
The present work was conducted to obtain and highlight the first comprehensive baseline data on atmospheric deposition of trace elements and to evaluate the air quality in Georgia. A total of 120 moss samples were collected over accessible territories in Georgia in the period from 2014 to 2017. Hylocomium splendens (Hedw.) Schimp., Hypnum cupressiforme (Hedw.), and Pleurozium schreberi (Brid.) Mitt. moss species were analyzed by two complementary analytical techniques: instrumental neutron activation analysis and atomic absorption spectrometry. Concentrations of 41 elements in mg/kg were determined. The concentrations were compared with the corresponding values in the literature and are in a good agreement, except for the concentration of Mg, Al, K, Ca, Ti, and Fe, which were higher than those reported for other countries. The principal component and discriminant analyses were implemented to extract information about the similar geochemical features and to decipher the provenance of the studied elements. The analysis showed that a considerable association of crustal elements and the provenance of elements can be considered as a mixture of geogenic and anthropogenic sources. In addition, the influence of different latitudinal climate zones on the distribution of elements in the atmospheric deposition was observed. The enrichment factor shows considerable values for Th and Zr. The spatial distribution of the pollution load index identifies four zones (#12, 38, 53, and 64). The potential ecological risk index and the risk index were calculated and it does not pose significant risk except As and Cd. The data obtained can be used as the first dataset of metal characterization of air pollution in Georgia.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Oligoelementos/análisis , Contaminación del Aire/análisis , Monitoreo Biológico , Briófitas/química , Bryopsida/química , Georgia , Metales/análisis , Metales Pesados/análisis , Análisis de Activación de Neutrones , Espectrofotometría Atómica , TitanioRESUMEN
The aim of the study is to carry out elemental analysis of traditional herbs used as medicinal plants for the treatment of diseases in southern Ethiopia. The medicinal plants are those frequently used by the local/traditional healers for the treatment of gastrointestinal diseases in the southern part of the country. The instrumental neutron activation analysis (INAA) technique was deployed using irradiation and counting facilities of the Nigeria Research Reactor-1. Results were obtained for some essential elements at various concentrations for six herbal medicines. The major elements found in samples analyzed include Ca, Mg, Cl, and K, whereas Al, Na, and Fe were found to be in minor concentrations. The estimated daily intake of the analyzed elements was determined and found to be below the upper tolerable limits set by FAO/WHO. Therefore, the results obtained from the analysis of these herbal medicinal plants can be useful for the treatment of diseases and pharmaceutical purposes.
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Enfermedades Gastrointestinales , Plantas Medicinales , Oligoelementos , Etiopía , Enfermedades Gastrointestinales/tratamiento farmacológico , Análisis de Activación de Neutrones , Nigeria , Oligoelementos/análisisRESUMEN
To evaluate the daily Se intake of 3- to 5-year-old Japanese children, we used seventy-two urine samples collected from fifty-three children (twenty-seven male and twenty-six female) from two cities in Miyagi prefecture, Japan. For measuring low Se concentrations with high precision, accuracy and rapidity in the 24-h urine samples, we developed an instrumental neutron activation analysis (INAA) method, that is without any chemical separation, using the short-lived 77mSe (t1/2 = 17·4 s) nuclide. The estimated Se intake of the fifty-three children was 51·5 (sd 30·2) µg/d (geometric mean: 42·7 µg/d). Ten subjects (three male and seven female), successfully provided 24-h urine samples over two or three consecutive days; their Se intake was 37·4 (sd 5·9) µg/d. Based on the logarithmically transformed data of these ten subjects, the ratio of intra-/inter-individual variances of usual Se intake was 16·7 (28·0/1·7) and geometric mean was 27·7 µg/d. The 5th to 95th percentile of usual Se intake of these ten subjects was 17·5 to 40·4 µg/d, which ranged between the recommended dietary allowance and tolerable upper intake level of Se by the Dietary Reference Intakes for Japanese (2015).
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Estado Nutricional , Selenio/orina , Peso Corporal , Preescolar , Ingestión de Alimentos , Femenino , Humanos , Japón , Masculino , Análisis de Activación de Neutrones/métodos , Ingesta Diaria RecomendadaRESUMEN
The aim of this work was to evaluate the variability in elemental composition of seven medicinal plants and their respective soils belonging to protected and nearby unprotected sites of the Hazarganji Chiltan National Park. The medical plants under study were Achillea wilhelmsii C. Koch, Peganum harmala Linn, Sophora mollis (Royle) Baker, Perovskia atriplicifolia Benth, Seriphidium quettense (Podlech.) Ling, Hertia intermedia (Bioss) O. Ktze, and Nepeta praetervisa Rech. F. Macro (C, H, N, S, K, Ca), micro (Cl, Cu, Fe, Mn, and Zn), beneficial (Al, Co, Na), others (As, Br, Cr, Cs, Hf, Pb, Rb, Sb, Sr, Sn, V and Th) and rare earth elements (Ce, Eu, La, Lu, Nd Sc, Sm, Tb and Yb) were characterized by means of standard organic elemental and instrumental neutron activation methodologies and by flame atomic absorption spectroscopy. Results showed that, among macro nutrients, carbon concentration was the highest element in both plant and soil samples followed by H and K. Elements such as Cl, Na and Fe were detected in considerably good amounts; all the other elements were found in trace quantities. Principal component analysis (PCA) was applied to identify spatial variation in elemental composition of medicinal plants, in which 80-90% of the total variance in whole set of data was found. In particular, the findings highlighted the presence of essential and beneficial elements such as C, H, N, K, Ca, Fe, Mn and Na, in samples from protected sites, while potentially dangerous elements such as Al, As, Br and Cr were detected in samples from unprotected sites. These results emphasized on the need for rational exploitation of valuable medicinal plants and supporting protected areas as an excellent source of biodiversity conservation.
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Elementos Químicos , Plantas Medicinales/química , Suelo/química , Carbono/análisis , Cloro/análisis , Hierro/análisis , Análisis de Activación de Neutrones/métodos , Nutrientes/análisis , Pakistán , Sodio/análisis , Espectrofotometría Atómica/métodos , Oligoelementos/análisisRESUMEN
The activity concentrations of natural 40K, 232Th, and 238U in 89 soil and 84 sediment samples collected over the entire Egyptian Nile River basin including the Nile delta are reported based on the results of epithermal neutron activation analysis. The average activity concentrations of 40K, 232Th, and 238U equal to 15.3 ± 6.6, 15.6 ± 11.1 and 220 ± 31 Bq/kg, respectively, are significantly lower than those reported for the Upper Continental Crust, World Average Sediments as well as World Average Soils, suggesting the presence of a considerable portion of mafic material, most probably originating from the Ethiopian High Plateau. Their average activity concentrations are statistically the same in soil and sediments, indicating that the Nile sediments and soil material are of the same origin. The main goal of this study was not only to estimate the radiological hazards but also to show the influence of sedimentary material transportable by the Blue Nile from the Ethiopian High Plateau. The different hazard indices like the radium equivalent, gamma index, external hazard as well as the internal hazard show a low radiological exposure either on direct contact or if local mud bricks are used in the construction of dwellings.
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Sedimentos Geológicos/análisis , Radioisótopos de Potasio/análisis , Ríos , Torio/análisis , Uranio/análisis , Egipto , Sedimentos Geológicos/química , Análisis de Activación de Neutrones/métodos , Monitoreo de Radiación/métodos , Suelo/química , Contaminantes Radiactivos del Suelo/análisisRESUMEN
The quality of dog diets depends on adequate ingredients capable of providing optimal nutrition and free of contaminants, for promoting long-term health. Trace elements in 95 samples of dry food for dog puppies (n = 32) and adults (n = 63) of various brands were measured using instrumental neutron activation analysis (INAA). The mass fractions of most elements were within the permissible limits for dogs. Aluminum, antimony, and uranium presented fairly high levels in some samples, which may imply health risks. Aluminum mass fractions ranged from <21 to 11,900 mg/kg, in same brand, super-premium dog food. Antimony mass fractions ranged up to 5.14 mg/kg, with the highest values measured in six samples of dog food from the same producer. The mass fractions of uranium was found up to 4 mg/kg in commercial brands from five different producers.
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Alimentación Animal/análisis , Perros , Oligoelementos/análisis , Animales , Antimonio/análisis , Inocuidad de los Alimentos , Análisis de Activación de Neutrones , Uranio/análisisRESUMEN
PURPOSE: This study was aimed to assess selenium and zinc status in female collegiate athletes and their relationship with dietary intake. METHODS: Female collegiate athletic groups of judo and aerobics, and healthy sedentary collegiate females were recruited for this study and their serum selenium and zinc contents were measured by the neutron activation analysis (NAA) method. In addition, the dietary intake of subjects was measured using the two days 24-hour recall method. RESULTS: Serum selenium in judo athletes was 10.7 µg/dl, which was significantly lower than that of aerobic athletes (12.2 µg/dl), but not different from that of the sedentary group (11.4 µg/dl). Additionally, serum zinc levels were 96.1 µg/dl and 90.2 µg/dl in aerobic and judo athletes, respectively, which did not differ significantly. Moreover, dietary selenium and zinc intake of the athletic groups did not differ significantly from that of the sedentary female group. Overall, 33.3% of the serum selenium concentration variation was explained by the intake of vitamin E, selenium and saturated fatty acids, while 14.7% of the serum zinc level variation was explained by the intake of saturated fatty acids. The strongest dietary indicator for serum selenium and zinc levels was saturated fatty acids intake. CONCLUSION: Judo athletes appear to have lower selenium status than aerobic athletes, suggesting different body selenium status according to sport type. To maintain body selenium and zinc levels, the dietary intake of saturated fatty acids should be decreased.
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Femenino , Humanos , Atletas , Ácidos Grasos , Artes Marciales , Métodos , Análisis de Activación de Neutrones , Selenio , Deportes , Vitamina E , Vitaminas , ZincRESUMEN
This study employs thermal and epithermal neutron activation analysis (NAA) to quantitatively and specifically determine absorption dose rates to various body parts from uranium, thorium and potassium. Specifically, a case study of bauxite residue (red mud) from an industrial facility was used to demonstrate the feasibility of the NAA approach for radiological safety assessment, using small sample sizes to ascertain the activities of 235U, 238U, 232Th and 40K. This proof-of-concept was shown to produce reliable results and a similar approach could be used for quantitative assessment of other samples with possible radiological significance. 238U and 232Th were determined by epithermal and thermal neutron activation analysis, respectively. 235U was determined based on the known isotopic ratio of 238U/235U. 40K was also determined using epithermal neutron activation analysis to measure total potassium content and then subtracting its isotopic contribution. Furthermore, the work demonstrates the application of Monte Carlo Neutral-Particle (MCNP) simulations to estimate the radiation dose from large quantities of red mud, to assure the safety of humans and the surrounding environment. Phantoms were employed to observe the dose distribution throughout the human body demonstrating radiation effects on each individual organ.
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Modelos Químicos , Análisis de Activación de Neutrones , Radioisótopos de Potasio/análisis , Dosis de Radiación , Monitoreo de Radiación/métodos , Torio/análisis , Uranio/análisis , Óxido de Aluminio , Método de Montecarlo , Fantasmas de ImagenRESUMEN
Two markers of regional exchange in the Eastern Mediterranean during the first millennium BCE are the White Painted and Bichrome Wares from Cyprus's Cypro-Geometric and Cypro-Archaic periods. Although these ceramics are often assumed to be imports from Cyprus, excavations in southern Turkey at sites such as Tarsus-Gözlükule, Kilise Tepe, Sirkeli Höyük, and Kinet Höyük suggest that at least some of this pottery was produced locally, requiring a major revision of our understanding of economic interaction in the Eastern Mediterranean. We employ a combination of portable x-ray fluorescence and neutron activation analysis to investigate the White Painted and Bichrome Wares recovered from Tell Tayinat, Çatal Höyük, and Tell Judaidah, three sites in the Amuq Valley of southeastern Anatolia. Our results demonstrate that a clear geochemical distinction exists between imported and local versions of this pottery. Through comparison with legacy datasets, we locate the likely origin of the imported pottery in the Circum-Troodos sediments of central and southern Cyprus. The secondary and tertiary settlements of Çatal Höyük and Tell Judaidah had access only to this imported material. In contrast, the inhabitants of Tell Tayinat, capital city of the region, consumed both imported and locally produced White Painted and Bichrome Wares. This pattern cannot be explained in purely economic terms whereby the frequency of imports decreases as distance from the point of production increases. Instead, we suggest that elite feasting practices drove demand, resulting in either local potters producing Cypriot-style pottery or Cypriot potters settling in the vicinity of Tell Tayinat. These findings offer new insights into the relationship between historically attested Iron Age kingdoms in southern Turkey and Cyprus and complicate our understanding of exchange in the Eastern Mediterranean during the Iron Age.
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Arqueología/métodos , Cerámica/análisis , Cerámica/química , Factores Socioeconómicos/historia , Chipre , Historia Antigua , Humanos , Análisis de Activación de Neutrones , Espectrometría por Rayos X , TurquíaRESUMEN
BACKGROUND: Although Asian populations consume relatively large amounts of fish and seafood and have a high prevalence of metabolic diseases, few studies have investigated the association between chronic mercury exposure and metabolic syndrome and its effect modification by selenium. METHODS: We analyzed baseline data from the Trace Element Study of Korean Adults in the Yeungnam area. Participants included 232 men and 269 women, aged 35 years or older, who had complete data regarding demographic, lifestyle, diet, toenail mercury and selenium levels, and health. Toenail mercury and selenium concentrations were measured using instrumental neutron-activation analysis. The metabolic biomarker levels were obtained through biannual medical checkups. RESULTS: Higher toenail mercury levels were associated with habitual consumption of whale and shark meats, older age, obesity, smoking, alcohol drinking, and higher household income. Multivariable analysis showed a positive association between toenail mercury exposure and metabolic syndrome. In addition, this association was significantly stronger at lower selenium levels and was weaker at higher selenium levels. CONCLUSION: The possible harmful effects of mercury on metabolic syndrome may be attenuated by high levels of selenium. Future studies are needed to suggest optimal dietary guidelines regarding fish and selenium intakes, particularly for Asians with high levels of fish intake.
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Contaminación de Alimentos , Mercurio/análisis , Síndrome Metabólico/epidemiología , Uñas/química , Estado Nutricional , Alimentos Marinos , Selenio/análisis , Adulto , Estudios Transversales , Femenino , Abastecimiento de Alimentos , Humanos , Modelos Lineales , Modelos Logísticos , Masculino , Mercurio/efectos adversos , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/prevención & control , Persona de Mediana Edad , Análisis Multivariante , Análisis de Activación de Neutrones , Encuestas Nutricionales , Oportunidad Relativa , Prevalencia , República de Corea/epidemiología , Medición de Riesgo , Factores de Riesgo , Alimentos Marinos/efectos adversos , Factores de Tiempo , Dedos del PieRESUMEN
Several diseases can be diagnosed observing the variation of specific elements concentration in body fluids. In this study the concentration of inorganic elements in blood samples of dystrophic (Dmd(mdx)/J) and C57BL/6J (control group) mice strain were determined. The results obtained from Energy Dispersive X-ray Fluorescence (EDXRF) were compared with Neutron Activation Analysis (NAA) technique. Both analytical techniques showed to be appropriate and complementary offering a new contribution for veterinary medicine as well as detailed knowledge of this pathology.
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Análisis Químico de la Sangre/métodos , Compuestos Inorgánicos/sangre , Análisis de Activación de Neutrones/métodos , Espectrometría por Rayos X/métodos , Animales , Modelos Animales de Enfermedad , Elementos Químicos , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , Distrofia Muscular de Duchenne/sangreRESUMEN
Hand bone equivalent phantoms (250 ml) carrying selenium in various amounts were irradiated and counted for in vivo neutron activation analysis (IVNAA) by employing a 4π NaI(TI) based detection system. During the analysis of counting data, a feature at a higher energy than the gamma ray peak from (77m)Se (0.162 MeV) was observed at 0.197 MeV. Further investigations were made by preparing water phantoms containing only de-ionized water in 250 ml and 1034 ml quantities. Neutrons were produced by the (7)Li(p,n)(7)Be reaction using the high beam current Tandetron accelerator. Phantoms were irradiated at a fixed proton energy of 2.3 MeV and proton currents of 400 µA and 550 µA for 30 s and 22 s respectively. The counting data saved using the 4π NaI(TI) detection system for 10 s intervals in anticoincidence, coincidence and singles modes of detection were analyzed. Areas under gamma peaks at energies 0.197 MeV and 1.357 MeV were computed and half-lives from the number of counts for the two peaks were established. It was concluded that during neutron activation of water phantoms, oxygen-18 is activated, producing short-lived radioactive 19O having T(1/2) = 26.9 s. Induced activity from 19O may contribute spectral interference in the gamma ray spectrum. This effect may need to be taken into account by researchers while carrying out IVNAA of biological subjects.
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Análisis de Activación de Neutrones/instrumentación , Radioisótopos de Oxígeno/análisis , Fantasmas de Imagen , Agua/química , Rayos gamma , Radioisótopos de Oxígeno/química , Selenio/químicaRESUMEN
Selenium (Se) is an element that, in trace quantities, plays an important role in the normal function of a number of biological processes in humans. Many studies have demonstrated that selenium deficiency in the body may contribute to an increased risk for certain neoplastic, cardiovascular, osseous, and nervous system diseases including retardation of bone formation. However, at higher concentrations Se is cytotoxic. For these reasons it is desirable to have a means of monitoring selenium concentration in humans.This paper presents the outcome of a feasibility study carried out for measuring selenium in humans using in vivo neutron activation analysis (IVNAA). In this technique a small dose of neutrons is delivered to the organ of interest, the neutrons are readily captured by the target nuclei, and the γ-rays given off are detected outside of the body. For the present study, human hand (bone) tissue equivalent phantoms were prepared with varying amounts of Se. These were irradiated by a low energy fast neutron beam produced by the (7)Li(p,n)(7)Be reaction employing the high beam current Tandetron accelerator. The counting data saved using a 4π NaI(TI) detection system were analyzed. The selenium was detected via the neutron capture reaction, (76)Se(n,γ)(77 m)Se, whereas calcium was detected through the (48)Ca(n,γ)(49)Ca reaction for the purpose of normalization of the Se signals to the calcium signals. From the calibration lines drawn between Se/Ca concentrations and Se/Ca counts ratio, the minimum detection limits (MDLs) were computed for two sets of phantoms irradiated under different irradiation parameters.In this study the optimized MDL value was determined to be 81 ng g(-1) (Se/phantom mass) for an equivalent dose of 188 mSv to the phantom. This MDL was found at least 10 times lower than the reported data on Se concentration measured in bone tissues. It was concluded that the NAA technique would be a feasible means of performing in vivo measurements of selenium in humans. Currently the data on in vivo measurement of selenium in humans are limited; the results of the present study would greatly contribute to the present data.
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Análisis de Activación de Neutrones/métodos , Selenio/análisis , Calcio/análisis , Calibración , Estudios de Factibilidad , Huesos de la Mano , Humanos , Límite de Detección , Fantasmas de ImagenRESUMEN
This paper provides an overview of analytical methods frequently used to identify terrestrial radionuclides in samples. While radioactivity is normally measured through the ionising radiation produced during the spontaneous decay of unstable atoms, selected radionuclides or their chemical elements can be quantified with instrumental techniques based on stimulated emission or counting of atoms. The advantages and disadvantages of these analytical methods are discussed. Particular attention is paid to X-ray fluorescence analysis of materials containing uranium and thorium. It is also possible to determine the area distributions of these chemical elements in samples with the use of scanning X-ray fluorescence systems.
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Radiación de Fondo , Planeta Tierra , Radioisótopos/análisis , Radiometría/métodos , Espectrometría por Rayos X , Microanálisis por Sonda Electrónica , Semivida , Espectrometría de Masas , Análisis de Activación de Neutrones , Radioisótopos de Potasio/análisis , Espectrometría por Rayos X/instrumentación , Torio/análisis , Uranio/análisisRESUMEN
Non-invasive in vivo neutron activation analysis (NAA) was used to measure the fluorine concentration in 35 people in Hamilton, Ontario, Canada. Measurement and precision data of this second generation NAA system were determined in 2013, and the results were compared with the performance of a first generation system used in a pilot study of 33 participants from the Hamilton area in 2008. Improvements in precision in line with those predicted by phantom studies were observed, but the use of fewer technicians during measurement seemed adversely to affect performance. We compared the levels of fluorine observed in people between the two studies and found them to be comparable. The average fluorine concentration in bone was found to be 3 ± 0.3 mg and 3.5 ± 0.4 mg F/g Ca for 2013 and 2008 measurements respectively. Ten people were measured in both studies; the observed average change in bone fluorine in this subgroup was consistent with that predicted by the observation of the relationship between bone fluorine and age in the wider group. In addition, we observed differences in the relationship between bone fluorine level and age between men and women, which may be attributable either to sex or gender differences. The rate of increase in fluorine content for men was found to be 0.096 ± 0.022 mg F/g Ca per year while the rate of increase for women was found to be slightly less than half that of men, 0.041 ± 0.017 mg F/g Ca per year. A discontinuity in the rate of increase in fluorine content with age was observed in women at around age 50. Bone fluorine content was significantly lower ([Formula: see text]) in women age 50 to 59 than in women age 40 to 49, which we suggest may be attributable to bone metabolism changes associated with menopause. We also observed increased fluorine levels in tea drinkers as compared to non-tea drinkers, suggesting tea may be a significant source of exposure in Canada. The rate of increase in fluorine content of the tea drinkers and the non-tea drinkers were found to be 0.127 (± 0.029) and 0.050 (± 0.009) mg F/g Ca per year respectively. Finally, we also obtained twelve bone samples from cadavers' skulls. Neutron activation analysis was used to determine the fluorine levels in these ex vivo samples. The rate of increase of fluorine content versus age for in vivo and ex vivo measurements were found to be 0.078 ± 0.014 and 0.078 ± 0.050 mg F/g Ca per year respectively. Excellent agreement was found between the fluorine levels determined in vivo and ex vivo using the two separate systems, providing confidence in the fluorine concentration data being measured in vivo.
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Huesos/química , Flúor/análisis , Análisis de Activación de Neutrones/métodos , Adulto , Anciano , Envejecimiento , Conducta de Ingestión de Líquido , Femenino , Mano , Cabeza , Humanos , Masculino , Persona de Mediana Edad , Análisis de Activación de Neutrones/instrumentación , Ontario , Fantasmas de Imagen , Caracteres Sexuales , Encuestas y Cuestionarios , Té , Factores de Tiempo , Población Urbana , Adulto JovenRESUMEN
In order to clarify the differences between Ag, Br, Ca, Co, Cr, Fe, Hg, K, Mg, Mn, Na, Rb, Sb, Sc, Se, and Zn contents in hyperplastic (patients with benign prostate hyperplasia (BPH), n = 32) and nonhyperplastic (control group of healthy male inhabitants, n = 32) prostates, an instrumental neutron activation analysis was performed. Mean values (M ± SΕΜ) for mass fraction (mg/kg, dry mass basis) of chemical elements in glands of patients with BPH were the following: Ag, 0.0346 ± 0.0060; Br, 30.4 ± 3.6; Ca, 2030 ± 165; Co, 0.0716 ± 0.0097; Cr, 1.073 ± 0.119; Fe, 130.0 ± 7.9; Hg, 0.232 ± 0.030; K, 14,470 ± 740; Mg, 1200 ± 80; Mn, 1.19 ± 0.09; Na, 11,610 ± 870; Rb, 14.7 ± 0.8; Sb, 0.163 ± 0.025; Sc, 0.0257 ± 0.0040; Se, 1.243 ± 0.079; and Zn, 1235 ± 92. It was observed that in BPH tissue, the mass fraction of Co (p < 0.015), Cr (p < 0.0002), Hg (p < 0.000007), K (p < 0.001), Rb (p < 0.048), Sb (p < 0.0001), and Se (p < 0.000001) were significantly higher than in controls. In the sixth to eighth decades, the mass fractions of almost all chemical elements in hyperplastic prostates did not depend from age. Our finding of correlation between pairs of prostatic chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element relationships with a benign hyperplastic transformation. The results apparently confirm the disturbed homeostasis of Zn and Se and some other chemical elements in the etiology of BPH.
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Análisis de Activación de Neutrones/métodos , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Bromo/análisis , Calcio/análisis , Cromo/análisis , Cobalto/análisis , Humanos , Hierro/análisis , Magnesio/análisis , Masculino , Mercurio/análisis , Metales Pesados/análisis , Persona de Mediana Edad , Potasio/análisis , Selenio/análisis , Plata/análisis , Sodio/análisis , Zinc/análisisRESUMEN
Fossil bones are often the only materials available for chronological reconstruction of important archeological sites. However, since bone is an open system for uranium, it cannot be dated directly and therefore it is necessary to develop models for the U uptake. Hence, a radial diffusion-adsorption (RDA) model is described. Unlike the classic diffusion-adsorption (D-A) model, RDA uses a cylindrical geometry to describe the U uptake in fossil bones. The model was applied across a transverse section of a tibia of an extinct megamammal Macrauchenia patachonica from the La Paz Local Fauna, Montevideo State, Uruguay. Measurements of spatial distribution of Na, K, Ca, and Mg were also performed by neutron activation analysis (NAA). Gamma-ray spectrometric U-series dating was applied to determine the age of the bone sample. From U concentration profile, it was possible to observe the occurrence of a relatively slow and continuous uranium uptake under constant conditions that had not yet reached equilibrium, since the uranium distribution is a âª-shaped closed-system. Predictions of the RDA model were obtained for a specific geochemical scenario, indicating that the effective diffusion coefficient D/R in this fossil bone is (2.4 ± 0.6)10(-12) cm(2)s(-1). Mean values of Na, K, Ca, and Mg contents along the radial line of the fossil tibia are consistent with the expected behavior for spatial distributions of these mineral elements across a modern bone section. This result indicates that the fossil tibia may have its mineral structure preserved.
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Arqueología/métodos , Fósiles , Modelos Teóricos , Paleontología/métodos , Tibia/química , Uranio/química , Adsorción , Animales , Calcio/química , Difusión , Mamíferos , Metales Ligeros/química , Análisis de Activación de Neutrones , Espectrometría gamma , Uranio/análisisRESUMEN
A new method has been developed for separation and purification of fission (99)Mo from neutron activated uranium-aluminum alloy. Alkali dissolution of the irradiated target (100mg) results in aluminum along with (99)Mo and a few fission products passing into solution, while most of the fission products, activation products and uranium remain undissolved. Subsequent purification steps involve precipitation of aluminum as Al(OH)3, iodine as AgI/AgIO3 and molybdenum as Mo-α-benzoin oxime. Ruthenium is separated by volatilization as RuO4 and final purification of (99)Mo was carried out using anion exchange method. The radiochemical yield of fission (99)Mo was found to be >80% and the purity of the product was in conformity with the international pharmacopoeia standards.