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1.
Pharmazie ; 68(1): 54-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23444781

RESUMO

The fullerene C60 is used in consumer products such as cosmetics owing to its antioxidative effects and is being developed for nanomedical applications. However, knowledge regarding the safety of fullerene C60, especially after oral administration, is sparse. Here, we examined the safety of fullerene C60 in mice after 7 d of exposure to orally administered polyvinylpyrrolidone (PVP)-wrapped fullerene C60 (PVP-fullerene C60). Mice treated with PVP-fullerene C60 showed few changes in the plasma levels of various markers of kidney and liver injury and experienced no significant hematologic effects. Furthermore, the histology of the colon of PVP-fullerene C60-treated mice was indistinguishable from that of control mice. These results suggest that PVP-fullerene C60 lacks toxicity after high-dose oral administration and indicate that PVP-fullerene C60 can be considered safe for oral medication. These data provide basic information that likely will facilitate the production of safe and effective forms of fullerene C60.


Assuntos
Fulerenos/farmacologia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/patologia , Administração Oral , Animais , Contagem de Células Sanguíneas , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colite/induzido quimicamente , Colite/patologia , Feminino , Fulerenos/administração & dosagem , Luz , Camundongos , Camundongos Endogâmicos C57BL , Povidona , Espalhamento de Radiação , Fixação de Tecidos
2.
J Neurosci Res ; 90(12): 2272-80, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22903516

RESUMO

Cellular activities within the brain display regional specificity and a neuronal and glia interdependence. Components characterizing the regional specificity of neurons have been identified. However, characterization of the astrocyte remains in question. To identify region specific features of astrocytes, we have characterized the molecular phenotype of cells derived from regions with different levels of neuronal excitability, the cortex and striatum. Astrocytes were identified in cryostat sections of adult rat brain by rapid immunostaining for glial fibrillary acidic protein (GFAP), and individual cells were collected from each region by using laser microdissection (LMD). Total RNA was isolated and subjected to DNA microarray analysis. At least eight genes showed a differential expression level. Among them, aquaporin 4 (AQP4), a water channel protein, was expressed at higher levels within the cortex compared with the striatum, as confirmed by immunohistochemistry. Primary cultured astrocytes isolated from rat cortex or striatum also showed a differential expression of AQP4. These data may reflect unique properties of astrocytes across different brain regions. However, they may also reflect the interactive demands of neurons with different activity levels. Further examination of the heterogeneous astrocyte populations within each region will lend additional support to the regional specificity of neuronal functions and neuronal-glial interactions.


Assuntos
Aquaporina 4/biossíntese , Astrócitos/metabolismo , Córtex Cerebral/metabolismo , Corpo Estriado/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Animais , Aquaporina 4/genética , Astrócitos/ultraestrutura , Células Cultivadas/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/crescimento & desenvolvimento , Corpo Estriado/citologia , Corpo Estriado/crescimento & desenvolvimento , Regulação da Expressão Gênica , Proteína Glial Fibrilar Ácida/análise , Masculino , Microscopia de Fluorescência , Proteínas do Tecido Nervoso/genética , Especificidade de Órgãos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos
3.
J Environ Monit ; 14(12): 3146-55, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23117411

RESUMO

¹³7Cs is one of the conservative tracers applied to the study of oceanic circulation processes on decadal time scales. To investigate the spatial distribution and the temporal variation of ¹³7Cs concentrations in surface seawater in the North Pacific Ocean after 1957, a technique for optimum interpolation (OI) was applied to understand the behaviour of ¹³7Cs that revealed the basin-scale circulation of Cs ¹³7Cs in surface seawater in the North Pacific Ocean: ¹³7Cs deposited in the western North Pacific Ocean from global fallout (late 1950s and early 1960s) and from local fallout (transported from the Bikini and Enewetak Atolls during the late 1950s) was further transported eastward with the Kuroshio and North Pacific Currents within several years of deposition and was accumulated in the eastern North Pacific Ocean until 1967. Subsequently, ¹³7Cs concentrations in the eastern North Pacific Ocean decreased due to southward transport. Less radioactively contaminated seawater was also transported northward, upstream of the North Equatorial Current in the western North Pacific Ocean in the 1970s, indicating seawater re-circulation in the North Pacific Gyre.


Assuntos
Radioisótopos de Césio/análise , Monitoramento de Radiação/métodos , Cinza Radioativa/análise , Água do Mar/química , Poluentes Radioativos da Água/análise , Modelos Químicos , Oceano Pacífico , Cinza Radioativa/estatística & dados numéricos , Movimentos da Água
4.
Brain Behav Immun ; 25(5): 850-62, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20833246

RESUMO

Current data suggests an association between elevations in interleukin 1 (IL-1)α, IL-1ß, and IL-6 and the proliferation of neural progenitor cells (NPCs) following brain injury. A limited amount of work implicates changes in these pro-inflammatory responses with diminished NPC proliferation observed as a function of aging. In the current study, adolescent (21day-old) and 1year-old CD-1 male mice were injected with trimethyltin (TMT, 2.3mg/kg, i.p.) to produce acute apoptosis of hippocampal dentate granule cells. In this model, fewer 5-bromo-2'-deoxyuridine (BrdU)+ NPC were observed in both naive and injured adult hippocampus as compared to the corresponding number seen in adolescent mice. At 48h post-TMT, a similar level of neuronal death was observed across ages, yet activated ameboid microglia were observed in the adolescent and hypertrophic process-bearing microglia in the adult. IL-1α mRNA levels were elevated in the adolescent hippocampus; IL-6 mRNA levels were elevated in the adult. In subgranular zone (SGZ) isolated by laser-capture microdissection, IL-1ß was detected but not elevated by TMT, IL-1a was elevated at both ages, while IL-6 was elevated only in the adult. Naïve NPCs isolated from the hippocampus expressed transcripts for IL-1R1, IL-6Rα, and gp130 with significantly higher levels of IL-6Rα mRNA in the adult. In vitro, IL-1α (150pg/ml) stimulated proliferation of adolescent NPCs; IL-6 (10ng/ml) inhibited proliferation of adolescent and adult NPCs. Microarray analysis of SGZ post-TMT indicated a prominence of IL-1a/IL-1R1 signaling in the adolescent and IL-6/gp130 signaling in the adult.


Assuntos
Hipocampo/lesões , Interleucina-1/fisiologia , Interleucina-6/fisiologia , Células-Tronco Neurais/fisiologia , Envelhecimento/fisiologia , Animais , Apoptose/fisiologia , Astrócitos/fisiologia , Proliferação de Células , Receptor gp130 de Citocina/fisiologia , Hipocampo/imunologia , Hipocampo/fisiologia , Interleucina-1alfa/fisiologia , Subunidade alfa de Receptor de Interleucina-6/fisiologia , Masculino , Camundongos , Microglia/fisiologia , Receptores Tipo I de Interleucina-1/fisiologia , Transdução de Sinais/fisiologia
5.
Poult Sci ; 89(8): 1709-15, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20634527

RESUMO

The present study investigated the cellular localization of 3 catecholamine biosynthetic enzymes, tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), and phenylethanolamine N-methyltransferase (PNMT) to identify and analyze the localization of norepinephrine (NE) and epinephrine (E) cells in the adrenal gland in the chicken using peroxidase-antiperoxidase immunohistochemical techniques. Tyrosine hydroxylase immunoreactivity (IR) was observed in almost all adrenal medullary cells of the adult chicken. Dopamine beta-hydroxylase IR coincided with that of TH. Many medullary cells also exhibited PNMT IR, but PNMT-immunonegative cells were also observed. Tyrosine hydroxylase IR was localized in the E- and NE-containing cells, but PNMT IR was localized only in the E-containing cells. Approximately 69% of medullary cells were E-containing, and the remaining were NE-containing cells. The ratio of E- and NE-containing cells between the subcapsular and central zone was statistically significant (P < 0.01). Although cortical cells of the adrenal gland did not show TH-, DBH-, or PNMT-positive reactions, ganglia close to the adrenal gland showed TH, DBH, and PNMT immunoreactivities. These findings indicated the cellular localization of 3 catecholamine-biosynthesizing enzymes in chicken adrenal medulla and suggest that the majority of medullary cell are E-containing cells. The ratio of E cells to NE cells varies among the 3 zones in the adrenal glands of the chicken.


Assuntos
Medula Suprarrenal/metabolismo , Catecolaminas/biossíntese , Galinhas/metabolismo , Medula Suprarrenal/anatomia & histologia , Medula Suprarrenal/enzimologia , Animais , Dopamina beta-Hidroxilase/metabolismo , Epinefrina/metabolismo , Feminino , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Masculino , Norepinefrina/metabolismo , Feniletanolamina N-Metiltransferase/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
6.
Opt Express ; 17(10): 7744-9, 2009 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-19434105

RESUMO

Using a partially deuterated KDP crystal for an optical parametric amplifier, we demonstrated ultrabroadband optical parametric chirped-pulse amplification of more than 250 nm bandwidth at a center wavelength of 1050 nm. We numerically show how to control the broadband phase matching conditions at different wavelengths to match center wavelengths of suitable broadband seed sources by adjusting the deuteration level in partially deuterated KDP.

7.
Rheumatol Int ; 29(11): 1367-71, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19115057

RESUMO

We report a case of Jaccoud's arthropathy with forefoot plantar callosity. The lesser toe metatarsal heads were resected and Swanson's double-stemmed flexible-hinge implant arthroplasty of the first metatarsophalangeal joint was performed. An osteolytic defect had formed around the implant after 2 years. Surgical revision comprised implant removal and synovectomy. Histology revealed a foreign-body reaction with birefringent material in multinucleated giant cells. Because the capsuloligamentous system is fragile in Jaccoud's arthropathy, we recommend resection arthroplasty or arthrodesis of the first MP joint as an initial operative approach.


Assuntos
Artroplastia de Substituição/efeitos adversos , Reação a Corpo Estranho/etiologia , Lúpus Eritematoso Sistêmico/complicações , Articulação Metatarsofalângica/anormalidades , Articulação Metatarsofalângica/cirurgia , Silicones/efeitos adversos , Adulto , Artrite Reumatoide , Artrodese , Feminino , Humanos
8.
Appl Radiat Isot ; 66(11): 1675-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18502651

RESUMO

Long-lived anthropogenic radionuclides ((137)Cs, (90)Sr, and Pu isotopes) have been determined in monthly atmospheric deposition samples collected in Japan since 1956. The maximum annual deposition occurred in 1963 after the large-scale atmospheric nuclear weapons testing of 1961-1962. In the 1980s, the fallout from the Chinese nuclear weapons tests was observed and the released radionuclides from the Chernobyl accident affected radioactive deposition in Japan until the early 1990s. Recently, the deposition rates have been boosted by the resuspension of radionuclides in deposited particles, the (239,240)Pu content of which may originate from dusts from the East Asian continent deserts and arid areas.


Assuntos
Atmosfera/análise , Exposição Ambiental/análise , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Cinza Radioativa/análise , Radioisótopos/análise , Medição de Risco/métodos , Atmosfera/química , Meia-Vida , Humanos , Internacionalidade , Japão , Doses de Radiação , Radioisótopos/química
9.
Acta Biol Hung ; 59 Suppl: 241-3, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18652398

RESUMO

Gonadotropin-releasing hormone (GnRH) is a ten-amino acid peptide hormone that plays pivotal roles in reproduction in vertebrates and octopus. Recently, six GnRH forms (t-GnRH-3-8) and four GnRH receptor subtypes (Ci-GnRHR-1-4) were identified in the protochordate, Ciona intestinalis. In this study, we show the functional modulation of Ci-GnRHR-1 via heterodimerization with the orphan receptor subtype, Ci-GnRHR-4. The dimerization between Ci-GnRHR-1 and R-4 was detected by co-immunoprecipitation and immunoblot analysis. Binding assays confirmed the binding of t-GnRHs to Ci-GnRHR-1 but not to R-4, and verified no alternation in ligand-binding affinity between Ci-GnRHR-1 homodimer and Ci-GnRHRI&4 heterodimer. The heterodimer was found to stimulate the elevation of intracellular calcium, time-extension of ERK phosphorylation, and up-regulation of cell proliferation, all in a ligand specific manner, compared with the Ci-GnRHR-1 homodimer. In combination, these results indicated that Ci-GnRHR-4 is not an inactive receptor, but a modulatory factor for Ci-GnRHR-1 in C. intestinalis.


Assuntos
Ciona intestinalis/metabolismo , Receptores LHRH/metabolismo , Animais , Cálcio/metabolismo , Proliferação de Células , Ciona intestinalis/citologia , Dimerização , Hormônio Liberador de Gonadotropina/química , Hormônio Liberador de Gonadotropina/metabolismo , Sistema de Sinalização das MAP Quinases , Modelos Biológicos , Estrutura Quaternária de Proteína , Receptores LHRH/química , Receptores LHRH/classificação , Transdução de Sinais
10.
Acta Biol Hung ; 59 Suppl: 237-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18652397

RESUMO

Ci-TK and Ci-TK-R are authentic tachykinin (TK) and TK receptor isolated from a protochordate, Ciona intestinalis. In this study, we investigated a novel function of TK as an enhancer of oocyte growth. Ci-TK-R is expressed specifically in the Ciona vitellogenic oocytes. Moreover, administration of Ci-TK to the Ciona ovary resulted in upregulation of gene expression and enzymatic activity of several proteases. Moreover, maturation of the Ciona oocytes from the vitellogenic stage to the post-vitellogenic stage was induced in the presence of Ci-TK, which was completely blocked by addition of protease inhibitors.


Assuntos
Ciona intestinalis/metabolismo , Neuropeptídeos/metabolismo , Receptores de Neuropeptídeos/metabolismo , Animais , Ciona intestinalis/genética , Evolução Molecular , Feminino , Neuropeptídeos/genética , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Receptores de Taquicininas/genética , Receptores de Taquicininas/metabolismo , Taquicininas/genética , Taquicininas/metabolismo , Vertebrados
11.
Mar Pollut Bull ; 135: 895-906, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30301112

RESUMO

The compartment model POSEIDON-R with an embedded food web model was used to assess 137Cs distributions in the Baltic and Black seas and off the Pacific coast of Japan during 1945-2020 due to the weapon testing and accidents at the Chernobyl and Fukushima Dai-ichi nuclear power plants. The results of simulations conducted with generic parameters agreed well with measurements of 137Cs concentrations in the water, bottom sediments, and in fish. In the Black and Baltic seas, salinity variations affected the transfer of 137Cs through the food web. The contamination of pelagic fish followed the water contamination with some delay, whereas demersal fish depuration was found to be related to decreasing 137Cs concentrations in the upper sediment layer. On the Pacific shelf off Japan, intensive currents and eddies caused the simulated depuration rates in fish to be one-two orders of magnitude larger than those in the semi-enclosed Black and Baltic seas.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Chernobyl , Acidente Nuclear de Fukushima , Modelos Teóricos , Poluentes Radioativos da Água/análise , Animais , Mar Negro , Simulação por Computador , Peixes , Cadeia Alimentar , Sedimentos Geológicos/análise , Japão , Oceanos e Mares , Oceano Pacífico , Monitoramento de Radiação
12.
MethodsX ; 5: 1251-1266, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364566

RESUMO

A detailed description of the advanced version of compartment model POSEIDON-R for the prediction of transport and fate of radionuclides in the marine environment is given. The equations of transfer of radionuclides in the water and bottom sediment compartments along with the dynamical food chain model are presented together with dose module to assess individual and collective doses to the population due to the regular and accidental releases of radionuclides. The method for the numerical solution of model equations is also presented. The modelling results for the northeast Atlantic shelf seas were compared with measurements of 137Cs. •The three-dimensional compartment model POSEIDON-R describes the transfer of radionuclides and their daughter products in marine environment as a results of regular or accidental releases. This includes any transfer through the water column and sediments.•The model is complemented by a dynamic food chain model for transfer of radioactivity in pelagic and benthic food webs.•The dose module in the model calculates internal and external doses for humans and non-human biota.

13.
Sci Total Environ ; 618: 80-92, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29127871

RESUMO

This paper focuses on how a community of researchers under the COMET (CO-ordination and iMplementation of a pan European projecT for radioecology) project has improved the capacity of marine radioecology to understand at the process level the behaviour of radionuclides in the marine environment, uptake by organisms and the resulting doses after the Fukushima Dai-ichi nuclear accident occurred in 2011. We present new radioecological understanding of the processes involved, such as the interaction of waterborne radionuclides with suspended particles and sediments or the biological uptake and turnover of radionuclides, which have been better quantified and mathematically described. We demonstrate that biokinetic models can better represent radionuclide transfer to biota in non-equilibrium situations, bringing more realism to predictions, especially when combining physical, chemical and biological interactions that occur in such an open and dynamic environment as the ocean. As a result, we are readier now than we were before the FDNPP accident in terms of having models that can be applied to dynamic situations. The paper concludes with our vision for marine radioecology as a fundamental research discipline and we present a strategy for our discipline at the European and international levels. The lessons learned are presented along with their possible applicability to assess/reduce the environmental consequences of future accidents to the marine environment and guidance for future research, as well as to assure the sustainability of marine radioecology. This guidance necessarily reflects on why and where further research funding is needed, signalling the way for future investigations.


Assuntos
Acidente Nuclear de Fukushima , Radioisótopos/análise , Água do Mar/análise , Poluentes Radioativos da Água/análise , Biota , Ecossistema , Japão , Monitoramento de Radiação
14.
J Radioanal Nucl Chem ; 318(3): 1587-1596, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30546185

RESUMO

Distributions of radiocaesium (134Cs and 137Cs) derived from the Tokyo Electric Power Company (TEPCO) Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident in the North Pacific Ocean in the summer of 2012 were investigated. We have estimated the radiocaesium inventory in the surface layer using the optimal interpolation analysis and the subducted amount into the central mode water (CMW) by using vertical profiles of FNPP1-134Cs and mass balance analysis as the first approach. The inventory of the 134Cs in the surface layer in the North Pacific Ocean in August-December 2012 was estimated at 5.1 ± 0.9 PBq on 1 October 2012, which corresponds to 8.6 ± 1.5 PBq when it was decay corrected to the date of the FNPP1 accident, 11 March 2011. It was revealed that 56 ± 10% of the released 134Cs into the North Pacific Ocean, which was estimated at 15.3 ± 2.6 PBq, transported eastward in the surface layer in 2012. The amount of 134Cs subducted in the CMW was estimated to be 2.5 ± 0.9 PBq based on the mass balance among the three domains of the surface layer, subtropical mode water, and CMW.

15.
Opt Express ; 15(14): 8598-602, 2007 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-19547193

RESUMO

A diode-pumped, cryogenically-cooled Yb:KYW regenerative amplifier utilizing chirped-pulse amplification and regenerative pulse shaping has been developed. An amplified pulse with an energy of 5.5 mJ and a broad bandwidth of 3.4 nm is achieved.

16.
Opt Express ; 15(8): 5018-23, 2007 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-19532750

RESUMO

We demonstrate ultra-broadband optical parametric chirpedpulse amplification of 300-nm bandwidth pumped by a broadband pulse delivered from a diode-pumped, cryogenically-cooled Yb:YLF chirped- pulse amplification laser.

17.
Sci Total Environ ; 381(1-3): 243-55, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17459459

RESUMO

The present plutonium and 137Cs concentrations in South Pacific Ocean surface waters were determined. The water samples were collected in the South Pacific mid-latitude region (32.5 degrees S) during the BEAGLE expedition conducted in 2003-04 by JAMSTEC. 239,240Pu concentrations in surface seawater of the South Pacific were in the range of 0.5 to 4.1 mBq m(-3), whereas 137Cs concentrations ranged from 0.07 to 1.7 Bq m(-3). The observed 239,240Pu and 137Cs concentrations in the South Pacific were almost of the same level as those in the North Pacific subtropical gyre. The surface 239,240Pu in the South Pacific subtropical gyre showed larger spatial variations than 137Cs, as it may be affected by physical and biogeochemical processes. The 239,240Pu/137Cs activity ratios, which reflect biogeochemical processes in seawater, were generally smaller than that observed in global fallout, except for the most eastern station. The 239,240Pu/137Cs ratios in the South Pacific tend to be higher than that in the North Pacific. The relationships between anthropogenic radionuclides and oceanographic parameters such as salinity and nutrients were examined. The 137Cs concentrations in the western South Pacific (the Tasman Sea) and the eastern South Pacific were negatively correlated with the phosphate concentration, whereas there is no correlation between the 137Cs and nutrients concentrations in the South Pacific subtropical gyre. The mutual relationships between anthropogenic radionuclides and oceanographic parameters are important for better understanding of transport processes of anthropogenic radionuclides and their fate in the South Pacific.


Assuntos
Radioisótopos de Césio/análise , Plutônio/análise , Monitoramento de Radiação , Água do Mar/química , Poluentes Radioativos da Água/análise , Oceano Pacífico , Cloreto de Sódio/análise , Movimentos da Água
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(6 Pt 2): 066404, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16906985

RESUMO

A model that solves simultaneously both the electron and atomic kinetics was used to generate a synthetic He alpha and satellite x-ray spectra to characterize a high intensity ultrashort laser driven Ar cluster target experiment. In particular, level populations were obtained from a detailed collisional-radiative model where collisional rates were computed from a time varying electron distribution function obtained from the solution of the zero-dimensional Boltzmann equation. In addition, a particle-in-cell simulation was used to model the laser interaction with the cluster target and provided the initial electron energy distribution function (EEDF) for the Boltzmann solver. This study suggests that a high density average, high, of 3.2 x 10(20) cm(-3) was held by the system for a time, delta tau, of 5.7 ps, and during this time the plasma was in a highly nonequilibrium state in both the EEDF and the ion level populations.

19.
Environ Sci Process Impacts ; 18(1): 126-36, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26662211

RESUMO

Optimal interpolation (OI) analysis was used to investigate the oceanic distributions of (134)Cs and (137)Cs released from the Tokyo Electric Power Company Fukushima Daiichi Nuclear Power Plant (FNPP1) accident. From the end of March to early April 2011, extremely high activities were observed in the coastal surface seawater near the FNPP1. The high activities spread to a region near 165°E in the western North Pacific Ocean, with a latitudinal center of 40°N. Atmospheric deposition also caused high activities in the region between 180° and 130°W in the North Pacific Ocean. The inventory of FNPP1-released (134)Cs in the North Pacific Ocean was estimated to be 15.3 ± 2.6 PBq. About half of this activity (8.4 ± 2.6 PBq) was found in the coastal region near the FNPP1. After 6 April 2011, when major direct releases ceased, the FNPP1-released (134)Cs in the coastal region decreased exponentially with an apparent half-time of about 4.2 ± 0.5 days and declined to about 2 ± 0.4 PBq by the middle of May 2011. Taking into account that the (134)Cs/(137)Cs activity ratio was about 1 just after release and was extremely uniform during the first month after the accident, the amount of (137)Cs released by the FNPP1 accident increased the North Pacific inventory of (137)Cs due to bomb testing during the 1950s and early 1960s by 20%.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Centrais Nucleares , Oceano Pacífico , Água do Mar/química , Movimentos da Água
20.
Appl Radiat Isot ; 109: 435-440, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26682891

RESUMO

Following the accident at the Fukushima Daiichi nuclear power plant, a campaign of sampling and measuring anthropogenic radionuclides in North Pacific seawater was set up. The main aim was to study natural processes using these radionuclides as tracers. Because of dilution, the activities of anthropogenic radionuclides at long range were very low and their measurement required advanced pre-concentration techniques and underground gamma-ray spectrometry. Data and metrological aspects of the measurements using HPGe-detectors are presented and discussed.


Assuntos
Bioensaio/métodos , Acidente Nuclear de Fukushima , Plâncton/química , Radioisótopos/análise , Radiometria/métodos , Água do Mar/química , Poluentes Radioativos da Água/análise , Monitoramento Ambiental/métodos , Oceano Pacífico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria gama/métodos
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