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1.
Chem Commun (Camb) ; 56(65): 9324-9327, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32671368

RESUMO

To visualize the electrochemical reactivity and obtain the diffusion coefficient of the anode of lithium-ion batteries, we used scanning electrochemical cell microscopy (SECCM) in a glovebox. SECCM provided the facet-dependent diffusion coefficient on a Li4Ti5O12 (LTO) thin-film electrode and detected the metastable crystal phase of LixFePO4.


Assuntos
Fontes de Energia Elétrica , Compostos de Lítio/análise , Lítio/química , Microscopia Eletroquímica de Varredura , Nanopartículas/química , Difusão , Eletrodos , Cinética
2.
Biosens Bioelectron ; 150: 111897, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31786018

RESUMO

Flexible wearable chemical sensors are emerging tools which target diagnosis and monitoring of medical conditions. One of the potential applications of wearable chemical sensors is therapeutic drug monitoring for drugs that have a narrow therapeutic range such as lithium. We have investigated the possibility of developing a fibre-based device for non-invasive lithium drug monitoring in interstitial fluid. A flexible cotton-based lithium sensor was coupled with a carbon fibre-based reference electrode to obtain a potentiometric device. In vitro reverse iontophoresis experiments were performed to extract Li+ from under porcine skin by applying a current density of 0.4 mA cm-2 via two electrodes. Carbon fibre-based reverse iontophoresis electrodes were fabricated and used instead of a conventional silver wire-based version and comparable results were obtained. The fibre-based Li+ sensor and reference electrodes were capable of determining the Li+ concentration in samples collected via reverse iontophoresis and the results compared well to those obtained by ion chromatography. Additionally, biocompatibility of the materials used have been tested. Promising results were obtained which confirm the possibility of monitoring lithium in interstitial fluid using a wearable sensor.


Assuntos
Antidepressivos/análise , Fibra de Algodão , Monitoramento de Medicamentos/instrumentação , Compostos de Lítio/análise , Técnicas Biossensoriais/instrumentação , Linhagem Celular , Fibra de Algodão/análise , Eletrodos , Estudos de Viabilidade , Humanos , Lítio/análise , Dispositivos Eletrônicos Vestíveis
3.
Radiat Prot Dosimetry ; 184(2): 216-223, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30496554

RESUMO

In this work, the initial results of the type testing of the LiF:Mg,Cu,P (TLD-100H) whole-body personal dosemeters are presented. An assessment of reproducibility, linearity of the response, the residual signal as a function of the dose, energy and angular dependence of the response was performed. In general, the dosemeters show good reproducibility for different dose values and a linear behaviour for a range between 0.1 and 300 mSv. The detection limits obtained are lower than 50 µSv. The system presents a good energy and angular response for different radiation qualities.


Assuntos
Cobre/análise , Fluoretos/análise , Compostos de Lítio/análise , Magnésio/análise , Fósforo/análise , Monitoramento de Radiação/métodos , Dosimetria Termoluminescente/métodos , Contagem Corporal Total/métodos , Humanos , Doses de Radiação , Monitoramento de Radiação/instrumentação , Dosimetria Termoluminescente/instrumentação
4.
Fortschr Neurol Psychiatr ; 87(9): 483-491, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-30453335

RESUMO

For avoiding affective episodes, patients with bipolar disorders are treated with mood stabilizers. Under that term, the substances lithium, valproic acid, lamotrigine and carbamazepine are included. In the light of upcoming new psychiatric concepts, the use of second generation antipsychotics is also taken into consideration in pharmacological treatment. In this review, the relation between brain structure and the use of lithium in bipolar disorders is examined. Therefore, results from MRI-, DTI-, SPECT-studies assessing this relation, were included.Most of the studies are cross-sectional and examined the effects of lithium. The latter is associated with increased cortical and sub-cortical gray matter volume and ameliorative white matter microstructure. 7-lithium spectroscopy showed a significant difference in brain-lithium concentrations between remitted and non-remitted patients.There are preclinical studies reporting induction of promitotic and antiapoptotic effects by lithium. This literature underpins the hypothesis of lithium-induced neurogenesis. However, osmotic and physical effects of lithium could also explain the demonstrated volume gain in bipolar human brain.Cross-sectional design and small patient groups are typical limitations of numerous studies included in this review.Notably, with the 7-lithium spectroscopy of the central nervous system, new perspectives in clinical research to clarify pharmacokinetic differences between remitted and non-remitted bipolar patients can be established in future.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/patologia , Compostos de Lítio/uso terapêutico , Indução de Remissão , Antimaníacos/análise , Antimaníacos/química , Antimaníacos/uso terapêutico , Antipsicóticos/análise , Antipsicóticos/química , Antipsicóticos/uso terapêutico , Transtorno Bipolar/psicologia , Estudos Transversais , Humanos , Compostos de Lítio/análise , Compostos de Lítio/química
5.
Molecules ; 24(1)2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30577631

RESUMO

We built a full-dimensional analytical potential energy surface of the ground electronic state of Li2H from ca. 20,000 ab initio multi-reference configuration interaction calculations, including core⁻valence correlation effects. The surface is flexible enough to accurately describe the three dissociation channels: Li (2s ²S) + LiH (¹Σ⁺), Li2 (¹Σg⁺) + H (1s ²S) and 2Li (2s ²S) + H (1s ²S). Using a local fit of this surface, we calculated pure (J = 0) vibrational states of Li2H up to the barrier to linearity (ca. 3400 cm-1 above the global minimum) using a vibrational self-consistent field/virtual state configuration interaction method. We found 18 vibrational states below this barrier, with a maximum of 6 quanta in the bending mode, which indicates that Li2H could be spectroscopically observable. Moreover, we show that some of these vibrational states are highly correlated already ca. 1000 cm-1 below the height of the barrier. We hope these calculations can help the assignment of experimental spectra. In addition, the first low-lying excited states of each B1, B2 and A2 symmetry of Li2H were characterized.


Assuntos
Hidrogênio/análise , Hidrogênio/química , Compostos de Lítio/análise , Compostos de Lítio/química , Modelos Químicos , Algoritmos
6.
Bipolar Disord ; 19(7): 563-567, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28714553

RESUMO

OBJECTIVE: Animal data suggest that subtherapeutic doses, including micro doses, of lithium may influence mood, and lithium levels in drinking water have been found to correlate with the rate of suicide. It has never been investigated whether consumption of lithium may prevent the development of bipolar disorder (primary prophylaxis). In a nation-wide population-based study, we investigated whether long-term exposure to micro levels of lithium in drinking water correlates with the incidence of bipolar disorder in the general population, hypothesizing an inverse association in which higher long-term lithium exposure is associated with lower incidences of bipolar disorder. METHODS: We included longitudinal individual geographical data on municipality of residence, data from drinking water lithium measurements and time-specific data from all cases with a hospital contact with a diagnosis of mania/bipolar disorder from 1995 to 2013 (N=14 820) and 10 age- and gender-matched controls from the Danish population (N= 140 311). Average drinking water lithium exposure was estimated for all study individuals. RESULTS: The median of the average lithium exposure did not differ between cases with a diagnosis of mania/bipolar disorder (12.7 µg/L; interquartile range [IQR]: 7.9-15.5 µg/L) and controls (12.5 µg/L; IQR: 7.6-15.7 µg/L; P=.2). Further, the incidence rate ratio of mania/bipolar disorder did not decrease with higher long-term lithium exposure, overall, or within age categories (0-40, 41-60 and 61-100 years of age). CONCLUSION: Higher long-term lithium exposure from drinking water was not associated with a lower incidence of bipolar disorder. The association should be investigated in areas with higher lithium levels than in Denmark.


Assuntos
Transtorno Bipolar/epidemiologia , Água Potável/química , Exposição Ambiental/estatística & dados numéricos , Compostos de Lítio/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Lítio , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Adulto Jovem
7.
J Clin Psychiatry ; 78(3): e252-e256, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28394506

RESUMO

OBJECTIVE: We investigated the association between lithium level in tap water and mental health problems, including depressive symptoms, anxiety, and aggressive and suicidal behaviors, in a general population of adolescents using a large individual-level dataset. METHODS: A school-based, cross-sectional survey was conducted in Kochi Prefecture in Japan between 2008 and 2009. Students in 24 public junior high schools were asked to anonymously complete a self-report questionnaire. The main outcome measures were mental health problems, including those on the 12-item General Health Questionnaire, interpersonal violence, bullying, destructive behavior, self-harm, and suicidal ideation. Samples were collected from sources that supplied drinking water to schools, and lithium levels were measured using atomic absorption spectrophotometry. The associations of lithium levels with mental health problems were examined using a generalized linear mixed model with schools as the fixed effect. Potential confounding factors were also added into the model. RESULTS: A total of 3,040 students among 3,311 students responded to the self-report questionnaire (response rate, 91.8%). The mean lithium concentration in tap water was 0.48 µg/L (SD = 0.52; range, 0.01 to 2.10; skewness = 2.01; kurtosis = 4.04), and it was relatively low compared with previous studies. In multivariable regression analysis, lithium level in tap water had an inverse association with depressive symptoms (P = .02) and interpersonal violence (P = .02) but not with suicidal behaviors (suicidal ideation, P = .82; self-harm, P = .46). CONCLUSIONS: Lithium level in tap water was inversely associated with depressive symptoms and interpersonal violence among a general population of adolescents and may have antidepressive and antiaggressive effects.


Assuntos
Água Potável/química , Compostos de Lítio/análise , Transtornos Mentais/prevenção & controle , Poluentes Químicos da Água/efeitos adversos , Poluentes Químicos da Água/análise , Adolescente , Estudos Transversais , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/prevenção & controle , Feminino , Inquéritos Epidemiológicos , Humanos , Japão , Modelos Lineares , Compostos de Lítio/uso terapêutico , Masculino , Ideação Suicida , Inquéritos e Questionários , Violência/prevenção & controle , Violência/psicologia
8.
Radiat Prot Dosimetry ; 170(1-4): 204-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27143792

RESUMO

Wide and common applications of ionising radiation require continuous improvement of radiation safety and dosimetry methods. The thermoluminescent (TL) method is well known and very popular. Apart from its advantages, it also carries certain disadvantages. The erasure of the TL signal on detector readout and the resulting impossibility of post-readout dose reassessment is one of them. At the Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN), a method for dose reassessment based on phototransferred thermoluminescence (PTTL) has been developed. This method has been applied for dose reassessment to MTS-N (LiF:Mg, Ti) detectors used in individual whole-body dosemeters and adjusted to an automatic reader used in routine measurements. The next step was to extend and adapt this method for extremity dosemeters. With the use of the PTTL method, it is possible to reassess relatively high doses measured on individual whole-body and extremity dosemeters collected from our customers after routine use. The influence of PTTL background has greater impact in extremity dosemeters where it is only one and thinner MTS-N detector compared with four MTS-N detectors in whole-body dosemeters. The minimum dose was determined as 5 mSv for extremity dosimetry. Below 5 mSv, the impact of PTTL background is comparable to the signal, and the estimated uncertainty of reassessed dose is at the level of reassessed dose.


Assuntos
Proteção Radiológica/métodos , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/métodos , Alumínio/química , Calibragem , Dedos/efeitos da radiação , Fluoretos/análise , Humanos , Luz , Modelos Lineares , Compostos de Lítio/análise , Magnésio/análise , Exposição Ocupacional/análise , Polônia , Dosímetros de Radiação , Monitoramento de Radiação/métodos , Software , Temperatura
9.
Radiat Prot Dosimetry ; 170(1-4): 177-80, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26503857

RESUMO

Thermoluminescence dosemeters are widely used in individual and environmental monitoring. The aim of this work was to compare the thermal stability of dosemeters of the Ext-Rad and whole-body card types with LiF:Mg,Ti and LiF:Mg,Cu,P detectors stored at different temperatures and periods. The dosemeters were stored at 0°C, room temperature and 40°C for periods that lasted 8, 30, 45, 90 and 120 d. In general, TLD-100H detectors present higher TL signal stability than TLD-100 detectors. The intensity of the signal remained constant for both materials for storage periods at 0°C. At RT the same results was observed for TLD-100H. For TLD-100 detectors, a maximum variation of 22 % was registered for the longest period. At 40°C the TL signal decreased with storage time for both detectors. The TL signal of TLD-100H detectors presented maximum variations of 12 % whereas for TLD-100 detectors, larger variations of 25 % were observed.


Assuntos
Dosímetros de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/métodos , Exposição Ambiental/análise , Fluoretos/análise , Humanos , Compostos de Lítio/análise , Magnésio/análise , Variações Dependentes do Observador , Fósforo/análise , Doses de Radiação , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Temperatura , Fatores de Tempo , Titânio/análise , Contagem Corporal Total
10.
Radiat Prot Dosimetry ; 171(3): 346-350, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26359334

RESUMO

The influence of pre- and post-irradiation annealing procedures on LiF:Mg,Cu,P (trade name MCP-N) thermoluminescent detector stability was investigated. The detectors were processed in four groups, undergoing complete or incomplete preparation cycles (containing pre- and/or post-irradiation annealing in various combinations). Each cycle was repeated 10 times. The decrease in the stability was observed in groups with pre-irradiation annealing procedure, and not observed in other groups that were found to be apparently stable. The influence of the thermal history on the properties of the detectors was also investigated by swapping the chosen groups of detectors with respect to the annealing cycles. Changes in the properties of the detectors were observed after next 10 cycles of measurements too. Exponential model was proposed to describe the trends observed at two parts of the experiment. Its application for the dose corrections related to the cycle number of the readout improves the accuracy of final dose determination.


Assuntos
Cobre/química , Fluoretos/química , Compostos de Lítio/análise , Magnésio/química , Fósforo/química , Monitoramento de Radiação/métodos , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/métodos , Calibragem , Temperatura Alta , Compostos de Lítio/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
11.
Radiat Prot Dosimetry ; 168(1): 19-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25634900

RESUMO

In this research, the effect of magnesium (Mg), copper (Cu) and phosphorus (P) impurities on dosimetry response of LiF:Mg,Cu,P phosphors is studied experimentally and by the simulation procedure. In the experimental procedure, LiF:Mg,Cu,P phosphors in the powder form were synthesised by chemical co-precipitation method. After annealing at 250°C for 10 min, known amounts of powder were exposed to gamma doses from 0.2 to 1 Gy. The activation energy of the electronic traps for the dosimetric peak at 150°C in LiF:Mg,Cu,P crystalline lattice obtained was 0.69 eV. In the simulation study, the role of stated dopants on electronic and structural properties of LiF crystalline lattice is investigated with the WIEN2 K Code. The activation energies of the electronic and hole traps for the dosimetric peak at the same temperature in LiF:Mg,Cu,P crystalline lattice obtained are 0.75 and 3.1 eV, respectively. It is shown that the experimental results are in agreement with simulation results.


Assuntos
Cobre/análise , Fluoretos/análise , Compostos de Lítio/análise , Magnésio/análise , Fósforo/análise , Dosimetria Termoluminescente/métodos , Simulação por Computador , Eletrônica , Raios gama , Medições Luminescentes , Microscopia Eletrônica de Varredura , Pós , Solubilidade , Temperatura , Difração de Raios X
12.
J Chromatogr A ; 1408: 87-92, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26184708

RESUMO

A sensitive analytical method using mixed mode HPLC separation coupled with charged aerosol detection (CAD) was developed for quantitative analysis of lithium. The method is capable of separating lithium ion from different drug matrices and other ions in a single run thus eliminating the organic matrix and ionic analyte interferences without extensive sample preparation such as derivatization and extraction. The separation space and chromatographic conditions are defined by systematic studies of the retention behaviors of lithium and potential interfering ions and different type of pharmaceutical APIs (active pharmaceutical ingredients) under reversed-phase, HILIC and cation/anion exchange mechanisms. Compared to other current analytical techniques for lithium analysis, the presented method provides a new approach and demonstrates high sensitivity (0.02ng for LOD and 0.08ng for LOQ in both standard and sample solution). The method has been validated for pharmaceutical samples and can be potentially applied to biological, food and environmental samples.


Assuntos
Compostos de Lítio/análise , Aerossóis , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cromatografia de Fase Reversa , Concentração de Íons de Hidrogênio , Concentração Osmolar , Sensibilidade e Especificidade
13.
Int Clin Psychopharmacol ; 30(1): 1-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25025988

RESUMO

Suicide is a serious public health problem worldwide, and many nations are committed to developing prevention programmes to reduce the incidence of suicide. To date, several strategies have been proposed for suicide prevention, both at the population and at the individual level, some of which may be pharmacological. In particular, a substantial amount of data show that lithium significantly reduces mortality in patients with mood disorders. Initiating from this evidence, some recent studies have investigated whether a relationship might exist between levels of lithium in drinking water and mortality rates for suicide in the general population. We have systematically reviewed all the articles published on this issue to date. The available literature indicates that higher lithium levels in drinking water may be associated with reduced risk of suicide in the general population.


Assuntos
Água Potável/análise , Compostos de Lítio/análise , Prevenção ao Suicídio , Abastecimento de Água/análise , Humanos , Fatores de Proteção , Medição de Risco , Fatores de Risco , Suicídio/psicologia
14.
J Pharm Biomed Anal ; 102: 509-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25459951

RESUMO

In this study, an ionic liquids (ILs) based extraction approach has been successfully applied to the extraction of essential oil from Farfarae Flos, and the effect of lithium chloride was also investigated. The results indicated that the oil yields can be increased by the ILs, and the extraction time can be reduced significantly (from 4h to 2h), compared with the conventional water distillation. The addition of lithium chloride showed different effect according to the structures of ILs, and the oil yields may be related with the structure of cation, while the chemical compositions of essential oil may be related with the anion. The reduction of extraction time and remarkable higher efficiency (5.41-62.17% improved) by combination of lithium salt and proper ILs supports the suitability of the proposed approach.


Assuntos
Medicamentos de Ervas Chinesas/análise , Líquidos Iônicos/análise , Extração Líquido-Líquido/métodos , Compostos de Lítio/análise , Óleos Voláteis/análise , Tussilago , Medicamentos de Ervas Chinesas/química , Flores , Química Verde/métodos , Líquidos Iônicos/química , Compostos de Lítio/química , Óleos Voláteis/química
15.
BMC Pharmacol Toxicol ; 15: 49, 2014 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25193402

RESUMO

BACKGROUND: Lithium intoxication has potentially fatal neurologic and cardiac side effects. Extracorporeal removal can therefore be lifesaving. The dialysance of lithium is high as it is a small molecule. Comparable to its neighbor in the periodic table, sodium, its intracellular accumulation hampers its removal by renal replacement therapy, despite its favorable size. For this reason the combination of short intermittent and prolonged dialysis may be a beneficial approach in acute lithium intoxication, yet only a report of such a combination has been published and actual removed lithium has not been quantified. CASE PRESENTATION: We describe the first measurement of lithium in the spent total dialysate treating an acute lithium overdose of a 44 year old Caucasian patient on chronic lithium therapy, undergoing extended dialysis. Extracorporeal therapy was initiated at a lithium serum concentration of 3.24 mmol/l. With blood/dialysate flow of 350 ml/min the 1.3 m² polysulfone dialyzer exhibited a maximum lithium clearance of 177 ml/min. After 4.1 hours of treatment the lithium level was lowered to 1.25 mmol/l. In the total spent dialysate 250 mg lithium, i.e. ~ 40% of the ingested amount were found. The subsequent extended dialysis over 9.5 hours further decreased serum levels to 0.79 mmol/l. Neurological symptoms improved within the first 60 min of treatment. The patient could be transferred to a psychiatric hospital on the morning after admission. CONCLUSION: Standard intermittent hemodialysis with subsequent extended dialysis can efficiently be employed in severe lithium intoxication by combining prompt a fast decrease of lithium blood levels and preventing rebound/assuring removal of redistributed lithium.


Assuntos
Compostos de Lítio/análise , Diálise Renal , Adulto , Feminino , Humanos , Compostos de Lítio/toxicidade
16.
Radiat Prot Dosimetry ; 162(1-2): 14-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25009186

RESUMO

Outdoor gamma radiation measurements in Cluj County, Romania have been performed using solid-state thermoluminescent detectors in order to develop a high-resolution database for natural gamma dose rates. Integrated measurements have been carried out for an exposure time of minimum 3 weeks. According to European Union requirements, the territory has been divided into 69 grids of 10 × 10 km. The cells were monitored using LiF:Mg,Cu,P detectors. For two locations the results were 136 ± 7 and 150 ± 7 nGy h(-1), respectively. These results can be explained by the existent geological substrate. The values ranged from 56 ± 4 to 150 ± 7 nGy h(-1), with an average value of 91 ± 2 nGy h(-1), being in agreement with the 2008 United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) Report. A high-resolution map of gamma dose rates in Cluj County is presented for the first time.


Assuntos
Cobre/análise , Fluoretos/análise , Raios gama , Compostos de Lítio/análise , Magnésio/análise , Fósforo/análise , Monitoramento de Radiação/instrumentação , Dosimetria Termoluminescente/instrumentação , Radiação de Fundo , Humanos , Doses de Radiação , Monitoramento de Radiação/métodos , Romênia , Dosimetria Termoluminescente/métodos
17.
Radiat Prot Dosimetry ; 162(1-2): 20-3, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25009188

RESUMO

Application of whole-body personal TL dosemeters based on a high-sensitivity LiF:Mg,Cu,P (MCP-N) in mixed field beta-gamma radiation has been characterised. The measurements were carried out with (90)Sr/(90)Y, (85)Kr and (137)Cs point sources to calculate the energy response and linearity of the TLD response in a dose range of 0.1-30 mSv. From the result, calibration curves were obtained, enabling the readout of individual dose equivalent Hp(10) from gamma radiation and Hp(0.07) from beta radiation in mixed field beta-gamma. Limitation of the methodology and its application are presented and discussed.


Assuntos
Raios gama , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Dosimetria Termoluminescente/instrumentação , Contagem Corporal Total/instrumentação , Radiação de Fundo , Partículas beta , Calibragem , Radioisótopos de Césio , Cobre/análise , Fluoretos/análise , Humanos , Compostos de Lítio/análise , Magnésio/análise , Exposição Ocupacional/análise , Fósforo/análise , Doses de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Radioisótopos de Estrôncio , Dosimetria Termoluminescente/métodos , Radioisótopos de Ítrio
18.
Int J Health Geogr ; 11: 19, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22695110

RESUMO

BACKGROUND: Lithium as a substance occurring naturally in food and drinking water may exert positive effects on mental health. In therapeutic doses, which are more than 100 times higher than natural daily intakes, lithium has been proven to be a mood-stabilizer and suicide preventive. This study examined whether natural lithium content in drinking water is regionally associated with lower suicide rates. METHODS: Previous statistical approaches were challenged by global and local spatial regression models taking spatial autocorrelation as well as non-stationarity into account. A Geographically Weighted Regression model was applied with significant independent variables as indicated by a spatial autoregressive model. RESULTS: The association between lithium levels in drinking water and suicide mortality can be confirmed by the global spatial regression model. In addition, the local spatial regression model showed that the association was mainly driven by the eastern parts of Austria. CONCLUSIONS: According to old anecdotic reports the results of this study support the hypothesis of positive effects of natural lithium intake on mental health. Both, the new methodological approach and the results relevant for health may open new avenues in the collaboration between Geographic Information Science, medicine, and even criminology, such as exploring the spatial association between violent or impulsive crime and lithium content in drinking water.


Assuntos
Compostos de Lítio/análise , Suicídio/estatística & dados numéricos , Abastecimento de Água/análise , Áustria/epidemiologia , Catolicismo , Geografia , Humanos , Análise de Regressão
19.
Appl Radiat Isot ; 69(9): 1282-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21561783

RESUMO

A computerized glow curve analysis (GCA) program for handling of thermoluminescence data originating from WinREMS is presented. The MATLAB program fits the glow peaks using the first-order kinetics model. Tested materials are LiF:Mg,Ti, CaF(2):Dy, CaF(2):Tm, CaF(2):Mn, LiF:Mg,Cu,P, and CaSO(4):Dy, with most having an average figure of merit (FOM) of 1.3% or less, with CaSO(4):Dy 2.2% or less. Output is a list of fit parameters, peak areas, and graphs for each fit, evaluating each glow curve in 1.5 s or less.


Assuntos
Dosimetria Termoluminescente/métodos , Fluoreto de Cálcio/análise , Fluoreto de Cálcio/química , Fluoretos/análise , Fluoretos/química , Compostos de Lítio/análise , Compostos de Lítio/química , Medições Luminescentes/métodos , Software , Dosimetria Termoluminescente/normas
20.
Radiat Prot Dosimetry ; 144(1-4): 161-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21450701

RESUMO

The phototransferred thermoluminescence (PTTL) technique is applied to the Harshaw LiF:Mg,Cu,P material. It is demonstrated that using 254-nm UV light, dose levels as low as 0.2 mGy can be re-estimated. The PTTL efficiency was found to be ∼ 6 % in the dose range of 0.2 mGy-1 Gy, and it appears to be dose-independent. This implies that a simple calibration factor could be applied to the PTTL data for the re-estimation of dose levels. It was demonstrated that with a proper choice of the TL readout parameters, and the UV-light irradiation conditions, dose levels that are relevant to personal or environmental dosimetry can be re-estimated.


Assuntos
Cobre/análise , Fluoretos/análise , Compostos de Lítio/análise , Magnésio/análise , Fósforo/análise , Dosimetria Termoluminescente/normas , Calibragem , Relação Dose-Resposta à Radiação , Monitoramento Ambiental/métodos , Humanos , Proteção Radiológica/métodos , Radiometria/métodos , Reprodutibilidade dos Testes , Dosimetria Termoluminescente/métodos , Raios Ultravioleta
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