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1.
Int J Biometeorol ; 65(1): 31-44, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33236243

RESUMO

Atmospheric electric fields (AEFs) are produced by both natural processes and electrical infrastructure and are increasingly recognized to influence and interfere with various organisms and biological processes, including human well-being. Atmospheric electric fields, in particular electromagnetic fields (EMFs), currently attract a lot of scientific attention due to emerging technologies such as 5G and satellite internet. However, a broader retrospective analysis of available data for both natural and artificial AEFs and EMFs is hampered due to a lack of a semantic approach, preventing data sharing and advancing our understanding of its intrinsic links. Therefore, here we create an ontology (ENET_Ont) for existing (big) data on AEFs within the context of biological systems that is derived from different disciplines that are distributed over many databases. Establishing an environment for data sharing provided by the proposed ontology approach will increase the value of existing data and facilitate reusability for other communities, especially those focusing on public health, ecology, environmental health, biology, climatology as well as bioinformatics.


Assuntos
Eletricidade , Campos Eletromagnéticos , Humanos , Disseminação de Informação , Estudos Retrospectivos , Semântica
2.
Climacteric ; 23(6): 559-565, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32960111

RESUMO

Malabsorption due to celiac disease (CD) may contribute to postmenopausal osteoporosis. This study aimed to survey participants with CD regarding their bone density, fractures, and bone-preserving medications; to compare tolerance of bone-preserving medications in participants with and without CD; and to review the evidence for CD screening and osteoporosis therapies in the setting of CD. We recruited 131 participants with CD and 102 participants without CD. Of those with CD, 87% were diagnosed in adulthood and 40% had no recognized gastrointestinal symptoms. In 21% CD was diagnosed after the diagnosis of osteoporosis and in 9% after a fracture. No difference was found in the tolerability of bone medications between participants with CD and those without. Review of the literature found that, although monitoring of bone health is recommended for patients with CD, screening for CD is not generally accepted for patients with osteoporosis, although studies of the prevalence of CD in osteoporosis had incomplete ascertainment methods. There is a lack of well-conducted studies and therefore insufficient data for the efficacy and tolerability of bone medication in CD. In conclusion, both CD and menopause lead to bone loss. Identifying CD in postmenopausal women should lead to modification of osteoporosis management.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea , Doença Celíaca/fisiopatologia , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Celíaca/complicações , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/prevenção & controle , Fraturas por Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Adulto Jovem
3.
J Environ Radioact ; 153: 31-50, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26717350

RESUMO

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of (90)Sr, (131)I and (137)Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters.


Assuntos
Organismos Aquáticos/metabolismo , Radioisótopos de Césio/metabolismo , Radioisótopos do Iodo/metabolismo , Modelos Teóricos , Monitoramento de Radiação/métodos , Radioisótopos de Estrôncio/metabolismo , Poluentes Radioativos da Água/metabolismo , Animais , Crustáceos/metabolismo , Peixes/metabolismo , Moluscos/metabolismo , Alga Marinha/metabolismo
4.
J Environ Radioact ; 137: 198-203, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25106024

RESUMO

A multilayer perceptron artificial neural network (ANN) model for the prediction of the (7)Be behaviour in the air as the function of meteorological parameters was developed. The model was optimized and tested using (7)Be activity concentrations obtained by standard gamma-ray spectrometric analysis of air samples collected in Belgrade (Serbia) during 2009-2011 and meteorological data for the same period. Good correlation (r = 0.91) between experimental values of (7)Be activity concentrations and those predicted by ANN was obtained. The good performance of the model in prediction of (7)Be activity concentrations could provide basis for construction of models which would forecast behaviour of other airborne radionuclides.


Assuntos
Poluentes Radioativos do Ar/análise , Berílio/análise , Redes Neurais de Computação , Radioisótopos/análise , Modelos Teóricos , Monitoramento de Radiação , Sérvia , Espectrometria gama
5.
Radiat Environ Biophys ; 49(4): 625-34, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20706729

RESUMO

There is a scarcity of data on transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates for use in the assessment of radiation exposure. Although mosses and lichens have been extensively used in biomonitoring programs, the data on transfer of radionuclides to these species are limited, particularly for natural radionuclides. To enhance the available data, activity concentrations of (137)Cs, (226)Ra and (228)Ra were measured in ants, mosses and lichens and corresponding undisturbed soil collected from semi-natural ecosystems in Serbia and Montenegro and biota/soil concentration ratios (CR) calculated. Since the majority of internal dose to biota is expected to come from (40)K, the activity concentrations of this radionuclide were also determined. The mean CR values for (137)Cs, (226)Ra and (228)Ra in ants analyzed in this study were found to be 0.02, 0.06 and 0.02, respectively. The mean CR values of radionuclides in mosses were found to be 2.84 for (137)Cs, 0.19 for (226)Ra and 0.16 for (228)Ra, while those in lichens were found to be 1.08 for (137)Cs, 0.15 for (226)Ra and 0.13 for (228)Ra. The CR values obtained in this study were compared with default CR values used in the ERICA Tool database and also with those reported in other studies.


Assuntos
Briófitas/efeitos da radiação , Monitoramento Ambiental/métodos , Líquens/efeitos da radiação , Monitoramento de Radiação/métodos , Radioisótopos/análise , Animais , Formigas , Biodiversidade , Radioisótopos de Césio/análise , Ecossistema , Geografia , Humanos , Rádio (Elemento)/análise , Poluentes Radioativos do Solo
6.
Radiat Prot Dosimetry ; 140(4): 369-77, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20400775

RESUMO

The activity concentrations of (226)Ra, (232)Th and (40)K in 178 samples from 52 locations of the territory of Belgrade, the capital of Serbia, were determined by gamma-ray spectrometry. Based on the results obtained, the values of absorbed gamma dose rate at 1 m above the ground, radium equivalent activity, external hazard index, annual effective dose, annual gonadal dose and excess lifetime cancer risk were calculated. The results of the present study were compared with values reported worldwide and also with internationally recommended values. The total absorbed dose rate varied between 24.7 and 89.6 nGy h(-1) with a mean of 60.5 nGy h(-1), which is close to the world average value. Since all estimated radiological impact assessment factors were lower than the recommended values there seems to be no radiological health hazard for the population living in the investigated area.


Assuntos
Raios gama , Neoplasias Induzidas por Radiação/prevenção & controle , Radioisótopos de Potássio/análise , Radiometria/métodos , Rádio (Elemento)/análise , Tório/análise , Monitoramento Ambiental/métodos , Humanos , Doses de Radiação , Monitoramento de Radiação/métodos , Radiação Ionizante , Risco , Sérvia , Poluentes Radioativos do Solo/análise
7.
J Environ Radioact ; 101(2): 159-64, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19836864

RESUMO

There is a lack of appropriate data on transfer of some radionuclides on many terrestrial biota groups. To expand the available data concentration ratios of (238)U, (226)Ra, (232)Th, (40)K and (137)Cs in mosses are presented in this paper. The relationship between concentration ratios of radionuclides and physicochemical characteristics of the underlying soil was also investigated. The data on concentration ratios obtained here will provide a useful addition to the currently used database of transfer parameters, particularly for natural radionuclides.


Assuntos
Briófitas/metabolismo , Ecossistema , Monitoramento de Radiação , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Briófitas/química , Radioisótopos de Césio/análise , Geografia , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Sérvia , Tório/análise , Urânio/análise
8.
Environ Monit Assess ; 157(1-4): 383-90, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18850291

RESUMO

In order to assess the contribution of emission sources to the pollution of areas remote from industrial facilities, a combined approach of enrichment factor analysis and multivariate statistics was used for detecting the origin of heavy metal pollution in the Zlatibor ecosystem, in Serbia. Samples of moss (Pleurozium schreberi, Hylocomium splendens, Scleropodium purum, Hypnum cupressiforme and Thuidum delicatulum) and of topsoil (0-5 cm) were collected in 2005. The concentrations of seven heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined in moss and soil samples by atomic absorption spectrometry. The results obtained by enrichment factor analysis and two multivariate statistical methods, principal component analysis and cluster analysis, enabled discrimination of the lithologic and anthropogenic sources of heavy metals in the mosses. Enrichment factors, calculated to evaluate the contribution to the metal content in moss from anthropogenic sources, revealed pollution of the investigated area by Cd and Pb, originating from long-range transport and fossil fuel burning.


Assuntos
Briófitas/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/análise , Análise por Conglomerados , Ecossistema , Poluição Ambiental/estatística & dados numéricos , Análise Multivariada , Sérvia
9.
Chemosphere ; 72(3): 491-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18433832

RESUMO

The study is dealing with the distribution and the origin of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) in soils from a priori non-polluted areas. Positive correlations with organic matter and clay content but not with pH have been observed for most of elements analyzed in this study. Correlations of some metals (Cr, Pb and Zn) and radionuclides (238U and 137Cs) observed for analyzed soils could be explained by their common affinity for clay minerals. Enrichment factor (EF) analysis and cluster analysis (CA) highlighted the lithogenic origin of Cr, Cu, Mn, Ni, Pb and Zn and pointed out the primary input of Cd from anthropogenic sources. It also revealed the need for detailed geochemical surveys in the future in order to decrease the uncertainty of discrimination between lithogenic and anthropogenic origin of metals of interest.


Assuntos
Metais Pesados/análise , Radioisótopos/análise , Poluentes do Solo/análise , Solo/análise , Radioisótopos de Césio/análise , Monitoramento Ambiental/métodos , Análise Multivariada , Urânio/análise
10.
Radiat Prot Dosimetry ; 121(3): 297-302, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16899469

RESUMO

The gamma dose rates due to naturally occuring terrestrial radionuclides ((226)Ra, (232)Th and (40)K) were calculated based on their activities in soil samples, determined by gamma-ray spectrometry. A total of 140 soil samples from 21 different regions of Serbia and Montenegro were collected. The gamma dose rates ranged from 7.40 to 29.7 nGy h(-1) for (226)Ra, from 12.9 to 46.5 nGy h(-1) for (232)Th and from 12.5 to 37.1 nGy h(-1) for (40)K. The total absorbed gamma dose rate due to these radionuclides varied from 34.5 to 97.6 nGy h(-1) with mean of 66.8 nGy h(-1). Assuming a 20% occupancy factor, the corresponding annual effective dose varied from 4.23 x 10(-5) to 11.9 x 10(-5) Sv with mean of 8.19 x 10(-5) Sv, i.e. the dose was lower than world wide average value. According to the values of external hazard index (mean: 0.39) obtained in this study, the radiation hazard was found to be insignificant for population living in the investigated area.


Assuntos
Raios gama , Radioisótopos de Potássio/análise , Monitoramento de Radiação , Radônio/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Radiação de Fundo , Humanos , Espectrometria gama , Iugoslávia
11.
J Environ Radioact ; 77(3): 381-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15381328

RESUMO

The aim of this work was (i) to determine the activity levels of 137Cs in mosses from highland ecosystems of Serbia and Montenegro, (ii) to find out if radiocesium is associated with essential biomacromolecules, and (iii) to investigate 137Cs distribution among intracellular compartments. It was found that biomolecules of mosses do not bind significant amounts of radiocesium (2.3-3.3% of the absorbed 137Cs), a behavior that was independent of the moss species. Cellular fractionation of mosses showed that membranes are the primary 137Cs-binding sites at the cellular level. They contained 26.1-43.1% of the initial radiocesium activity. It seems that 137Cs-binding molecules in different mosses are of similar chemical nature, and their distribution between various cellular compartments is not species specific.


Assuntos
Bryopsida/química , Radioisótopos de Césio/análise , Poluentes Radioativos/análise , Bryopsida/metabolismo , Fracionamento Celular , Membrana Celular/química , Acidente Nuclear de Chernobyl , Monitoramento Ambiental , Iugoslávia
12.
Physiol Res ; 50(2): 205-14, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11522049

RESUMO

The effects of Lathyrus sativus neurotoxin were studied on the cell membrane potential and cellular cation composition in Retzius nerve cells of the leech Haemopis sanguisuga, with ion-selective microelectrodes using liquid ion-exchangers. Bath application of 10(-4) mol/l Lathyrus sativus neurotoxin for 3 min depolarized the cell membrane potential and decreased the input resistance of directly polarized membrane in Retzius neurons. At the same time the cellular Na+ activity increased and cellular K+ activity decreased with slow but complete recovery, while the intracellular Ca2+ concentration was not changed. Na+-free Ringer solutions inhibited the depolarizing effect of the neurotoxin on the cell membrane potential. Zero-Ca2+ Ringer solution or Ni2+-Ringer solution had no influence on the depolarizing effect of the neurotoxin on the cell membrane potential. It is obvious that the increase in membrane conductance and depolarization of the cell membrane potential are due to an influx of Na+ into the cell accompanied by an efflux of K+ from the cell.


Assuntos
Diamino Aminoácidos/toxicidade , Lathyrus , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Neurotoxinas/toxicidade , Animais , Cálcio/metabolismo , Eletrofisiologia , Sanguessugas , Potenciais da Membrana/efeitos dos fármacos , Microeletrodos , Potássio/metabolismo , Sódio/metabolismo
13.
Srp Arh Celok Lek ; 122(3-4): 123-5, 1994.
Artigo em Sérvio | MEDLINE | ID: mdl-17972830

RESUMO

The first written serbian medical records could be found in the Middle Ages (XIIIth century) when the serbian state was very well organized. St. Save was the son of Grand-Prince Stefan Nemanja (1171-1196), founder of the Serbian independent state and of a powerful dynasty that ruled Serbia for two centuries. At that time the first hospital service was established, and the social program which regulated the relationship between marriage and family, and the kind of therapy, was under the church and state control.


Assuntos
Educação Médica/história , Serviços de Saúde/história , Previdência Social/história , História Medieval , Humanos , Iugoslávia
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