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1.
BMC Public Health ; 19(1): 1615, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791296

RESUMO

BACKGROUNDS: The efforts to develop research and training on physical rehabilitation in regards to disasters is considered recent worldwide. In the late evening of the 11th up until the 12th of January of 2011, the most massive natural disaster occurred in Brazil with extremely heavy downpour, abrupt flood, as well as landslides on multiple areas of the Mountain Region of Rio de Janeiro. The objective of this research was to investigate the challenges in terms of physical rehabilitation provided by this event METHODS: The cross-sectional mixed method's study, which was conducted in the city of Nova Friburgo, used two different data sources: hospital records on traumatic injuries pre and post disaster, and interviews with key informants - victims who suffered injuries related to the disaster, professionals from rehabilitation services in the municipality, and also the city's health service management. Pearson's chi-squared test was performed to evaluate statistical significance between the week of a given incident and the type of injury. Interviews were transcribed and analysed through content analysis. RESULTS: A total of 2326 hospital records and 27 interviews were analysed. The proportion of traumatic injury in the municipal emergency service increased from 16% in the prior week, to 40% in the week post-disaster (p <  0.0001). Different injuries were identified: multiple fractures, crushing, amputation, perforation of soft tissues, inhalation of dust and establishment of chronic conditions through stress. Despite this scenario, out of the 16 health professionals interviewed, twelve did not observe an increase in the demand for outpatient rehabilitation services after the disaster. Interviews with the victims revealed that the pathways for care ran into different barriers. From 11 victims interviewed, only one received complete physiotherapy care through the public health services in the city, while all others hired additional assistance, received volunteer services, had assistance in other cities or remained without rehabilitation. CONCLUSIONS: The needs for rehabilitation increased after the disaster; however, the demand was repressed due to different barriers such as competing needs and possible lack of medical referral. Recommendations were made, including the action of performing a search of victims with rehabilitation needs.


Assuntos
Deslizamentos de Terra , Desastres Naturais , Reabilitação/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/reabilitação , Brasil/epidemiologia , Estudos Transversais , Planejamento em Desastres/organização & administração , Serviços Médicos de Emergência/estatística & dados numéricos , Inundações , Acessibilidade aos Serviços de Saúde , Administração de Serviços de Saúde/estatística & dados numéricos , Humanos , Ferimentos e Lesões/etiologia
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 198: 145-149, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29525565

RESUMO

In this work we present the analysis of dental enamel treated with an over-the-counter whitening product, bought in e-commerce at a very low cost, used without medical supervision in an abusive manner, in order to evaluate its demineralization action. Moreover, we studied the influence of renewal or non-renewal of saliva solution in which the specimens were stored throughout the study. The Degree of Demineralization was determined through the evaluation of the PO43- symmetric stretching band (~959cm-1) in Raman spectra of the specimens in different days during the course of the study. Results showed that a maximum of demineralization occurred between days 27 and 34 of application. Titration of the whitening product revealed a content of hydrogen peroxide 170-fold higher than what is allowed in Europe, according with legislation. Despite this extreme concentration of hydrogen peroxide, the demineralization was not as great as could be expected suggesting an important role of the pH of the solution in this demineralization mechanism.


Assuntos
Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Análise Espectral Raman/métodos , Clareadores Dentários/farmacologia , Humanos , Peróxido de Hidrogênio/análise , Minerais/metabolismo , Saliva , Clareadores Dentários/análise
3.
Genet Mol Res ; 16(3)2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28973749

RESUMO

The objective of this study was to evaluate the genetic diversity of soybean cultivars by adopting phenotypic traits and enzymatic markers, the relative contribution of agronomic traits to diversity, as well as diversity between the level of technology used in soybean cultivars and genetic breeding programs in which cultivars were inserted. The experiments were conducted on the field at the Center for Scientific and Technological Development in crop-livestock production and the Electrophoresis Laboratory of Lavras Federal University. The agronomic traits adopted were grain yield, plant height, first legume insertion, plant lodging, the mass of one thousand seeds, and days for complete maturation, in which the Euclidean distance, grouped by Tocher and UPGMA criteria, was obtained. After electrophorese gels for enzymatic systems, dehydrogenase alcohol, esterase, superoxide dismutase, and peroxidase were performed. The genetic similarity estimative was also obtained between genotypes by the Jaccard coefficient with subsequent grouping by the UPGMA method. The formation of two groups was shown using phenotypic characters in the genetic diversity study and individually discriminating the cultivar 97R73 RR. The character with the greatest contribution to the genetic divergence was grain yield with contribution higher than 90.0%. To obtain six different groups, individually discriminating the cultivars CG 8166 RR, FPS Jupiter RR, and BRS MG 780 RR, enzymatic markers were used. Cultivars carrying the RR technology presented more divergence than conventional cultivars and IPRO cultivars.


Assuntos
Genótipo , Glycine max/genética , Fenótipo , Polimorfismo Genético , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Esterases/genética , Esterases/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Melhoramento Vegetal/métodos , Melhoramento Vegetal/normas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas , Glycine max/enzimologia , Glycine max/crescimento & desenvolvimento , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
4.
Genet Mol Res ; 16(3)2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28973778

RESUMO

Estimating genotype x environment (GxE) parameters for quality and yield in soybean seed grown in different environments in Minas Gerais State was the goal of this study, as well as to evaluate interaction effects of GxE for soybean seeds yield and quality. Seeds were produced in three locations in Minas Gerais State (Lavras, Inconfidentes, and Patos de Minas) in 2013/14 and 2014/15 seasons. Field experiments were conducted in randomized blocks in a factorial 17 x 6 (GxE), and three replications. Seed yield and quality were evaluated for germination in substrates paper and sand, seedling emergence, speed emergency index, mechanical damage by sodium hypochlorite, electrical conductivity, speed aging, vigor and viability of seeds by tetrazolium test in laboratory using completely randomized design. Quadratic component genotypic, GXE variance component, genotype determination coefficient, genetic variation coefficient and environmental variation coefficient were estimated using the Genes software. Percentage analysis of genotypes contribution, environments and genotype x environment interaction were conducted by sites combination two by two and three sites combination, using the R software. Considering genotypes selection of broad adaptation, TMG 1179 RR, CD 2737 RR, and CD 237 RR associated better yield performance at high physical and physiological potential of seed. Environmental effect was more expressive for most of the characters related to soybean seed quality. GxE interaction effects were expressive though genotypes did not present coincidental behavior in different environments.


Assuntos
Interação Gene-Ambiente , Glycine max/genética , Característica Quantitativa Herdável , Sementes/genética , Genótipo , Germinação/genética , Modelos Genéticos , Sementes/crescimento & desenvolvimento , Glycine max/crescimento & desenvolvimento
5.
Genet Mol Res ; 16(2)2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28510255

RESUMO

This study aimed at verifying the adaptability and stability of soybean cultivars, considering the grain yield and quality of seeds, adopting univariate and multivariate approaches. The experiments were conducted in two crops, three environments, in 2013/2014 and 2014/2015 crop seasons, in the county of Inconfidentes, Lavras, and Patos de Minas, in the Minas Gerais State, Brazil. We evaluated 17 commercial soybean cultivars. For adaptability and stability evaluations, the Graphic and GGE biplot methods were employed. Previously, a selection index was estimated based on the sum of the standardized variables (Z index). The data relative to grain yield, mass of one thousand grain, uniformity test (sieve retention), and germination test were standardized (Zij) per cultivar. With the sum of Zij, we obtained the selection index for the four traits evaluated together. In the Graphic method evaluation, cultivars NA 7200 RR and CD 2737 RR presented the highest values for selection index Z. By the GGE biplot method, we verified that cultivar NA 7200 RR presented greater stability in both univariate evaluations, for grain yield, and for selection index Z.


Assuntos
Aclimatação , Grão Comestível/genética , Glycine max/genética , Melhoramento Vegetal/métodos , Grão Comestível/crescimento & desenvolvimento , Característica Quantitativa Herdável , Seleção Genética , Glycine max/crescimento & desenvolvimento
6.
Genet Mol Res ; 15(4)2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27886331

RESUMO

Forest fragmentation reduces the effective size of natural populations, isolates individuals in the landscape, and, consequently, changes species' mating systems by increasing the degree of relatedness between individuals and inbreeding. Investigating the impact of habitat degradation on forest fragments helps to assess the genetic and ecological consequences of these changes, and allows the development of effective and sustainable conservation strategies to manage the genetic resources of species living in degraded landscapes. The aim of the present study was to assess the genetic diversity of fragmented Theobroma speciosum populations using microsatellite markers. Three urban forest fragments were selected in the municipality of Alta Floresta, Mato Grosso State, Brazil, namely C/E park, J park, and Zoo Botanical park. Seventy-five individuals (25 in each fragment) were sampled by collecting their leaves for genomic DNA extraction. Polymerase chain reaction amplifications were performed using nine polymorphic simple sequence repeat primers, which amplified 84 alleles. The mean expected heterozygosity was 0.970, and it was always higher than the observed heterozygosity. Analysis of molecular variance revealed that most variability occurred within populations (64%) rather than between them (36%). The Structure software and an unweighted pair group method with arithmetic mean dendrogram revealed three distinct groups, showing that individuals were allocated to their correct populations. Genotype number 3 from C/E park, number 45 from J park, and number 51 from Zoo Botanical park could be used as stock plants in breeding programs, because they were the most dissimilar within the populations studied. The high genetic diversity levels detected in all three populations studied emphasize the importance of protecting this species in its natural habitat.


Assuntos
Cacau/genética , Variação Genética , Genoma de Planta , Genótipo , Perda de Heterozigosidade , Filogenia , Seleção Genética
7.
Talanta ; 155: 107-15, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27216663

RESUMO

In this work, a non-commercial triaxial geometry energy dispersive X-ray Fluorescence (EDXRF) setup and a benchtop µ-XRF system were used to identify postmortem contamination in buried bones. For two of the individuals, unusually high concentrations of Cu and Pb, but also Zn (in one individual) were observed. The pigments of the burial shroud coverings have been identified as the source of contamination. Accurate and precise quantitative results were obtained by nondestructive process using fundamental parameters method taking into account the matrix absorption effects. A total of 30 bones from 13 individuals, buried between the mid-XVIIIth to early XIXth centuries, were analyzed to study the elemental composition and elemental distribution. The bones were collected from a church in Almada (Portugal), called Ermida do Espírito Santo, located near the Tagus River and at the sea neighbourhood. The triaxial geometry setup was used to quantify Ca, Fe, Cu, Zn, Br, Sr and Pb of powder pressed bone pellets (n=9 for each bone). Cluster analysis was performed considering the elemental concentrations for the different bones. There was a clear association between some bones regarding Fe, Cu, Zn, Br and Pb content but not a categorization between cortical and trabecular bones. The elemental distribution of Cu, Zn and Pb were assessed by the benchtop µ-analysis, the M4 Tornado, based on a polycapillary system which provides multi-elemental 2D maps. The results showed that contamination was mostly on the surface of the bone confirming that it was related to the burial shroud covering the individuals.


Assuntos
Osso e Ossos/química , Osso e Ossos/diagnóstico por imagem , Imagem Molecular , Espectrometria por Raios X , Arqueologia , Autopsia , Humanos , Limite de Detecção
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 153: 379-85, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26344483

RESUMO

This case study illustrates the analytical characterization of 12 academic nude paintings by Veloso Salgado, made between 1883 and 1893. The study was done with in situ methods (infrared reflectography and EDXRF) and benchtop equipment (Raman and FTIR microscopes and SEM-EDS). Infrared reflectography revealed underdrawings, painting style, execution method and retouched/restored areas. Analytical techniques allowed the identification of gypsum, lead white, barium white, zinc white, yellow ochre, chrome yellow, zinc yellow, vermilion, synthetic ultramarine blue, cerulean blue, Prussian blue, viridian, green earth, Paris green, red ochre, raw umber and lamp black. These results provide valuable information on Salgado's palette and his artistic production technique and allow the distinction between palettes used in Lisbon and Paris and consequently, technical interchanges between both Academies. Finally, this study intends to start a systematic analytical study of the Faculty of Fine Arts' collection, allowing the characterization of many other authors and their influences for the development of painting methodology in this Academy.

9.
Genet Mol Res ; 14(4): 18047-58, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26782452

RESUMO

The identification of genes related to heat tolerance is fundamental for the development of high-quality seeds that are tolerant to heat stress condition. The objective of this study was to evaluate maize lineages and the gene expression involved in high temperature tolerance during germination using physiological tests, proteomics, and transcriptome analysis. Seeds from six maize lineages (30, 44, 54, 63, 64, and 91) with different levels of tolerance to high temperatures were used. Lineages 54 and 91 were observed to be more tolerant to high temperature conditions. The highest expression of α-amylase was observed in maize seeds from lineages 30 and 91 that were subjected to controlled deterioration. The highest expression of α-amylase was observed in maize seeds from lineages 30 and 91 that were subjected to controlled deterioration; with the controlled deterioration, the highest level of gene expression did not occur in the most tolerant materials; the association of lower expression of genes involved in heat-resistant protein systems was observed in seeds from lineage 44, which were more susceptible to high temperatures, and the highest gene expression of LEA D-34, ZmAN13, and AOX-1 was observed in seeds from lineage 64 when submitted to controlled deterioration.


Assuntos
Germinação/genética , Sementes/genética , Estresse Fisiológico/genética , Zea mays/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Sementes/fisiologia , Temperatura , Zea mays/fisiologia , alfa-Amilases/biossíntese
10.
Mar Pollut Bull ; 90(1-2): 115-20, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25499965

RESUMO

An experiment was carried out on an estuarine mudflat to assess impacts of inorganic nutrients used to fertilize sugar-cane fields on the surrounding aquatic ecosystem, through changes in the nematode community structure. During 118 days, nine quadrats each 4m(2) were sampled six times after the beginning of fertilizer addition. The fertilizer was introduced weekly in six areas, at two different concentrations (low and high doses), and three areas were used as control. The introduction of nutrients modified key nematode community descriptors. In general, the nematodes were negatively affected over the study period. However, Comesa, Metachromadora, Metalinhomoeus, Spirinia and Terschellingia were considered tolerant, and other genera showed different degrees of sensitivity. Nutrient input also affect the availability and quality of food, changing the nematode trophic structure. The use of inorganic fertilizer should be evaluated with care because of the potential for damage to biological communities of coastal aquatic systems.


Assuntos
Ecossistema , Eutrofização , Fertilizantes , Nematoides/fisiologia , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Estuários , Cadeia Alimentar
11.
Rev Sci Instrum ; 85(6): 063113, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24985805

RESUMO

In this work, we have built a portable X-ray fluorescence (XRF) spectrometer in a planar configuration coupled to a Raman head and a digital optical microscope, for in situ analysis. Several geometries for the XRF apparatus and digital microscope are possible in order to overcome spatial constraints and provide better measurement conditions. With this combined spectrometer, we are now able to perform XRF and Raman measurements in the same point without the need for sample collection, which can be crucial when dealing with cultural heritage objects, as well as forensic analysis. We show the capabilities of the spectrometer by measuring several standard reference materials, as well as other samples usually encountered in cultural heritage, geological, as well as biomedical studies.

12.
Neurotoxicology ; 44: 91-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24907645

RESUMO

Lead is a potent toxicant associated with adverse cardiovascular effects and hypertension in children. Yet, few studies have determined if autonomic dysfunction associated with lead exposure involves brain regions which regulate autonomic responses. Central autonomic nuclei such as the nucleus tractus solitarius (NTS) and hypothalamic defence area (HDA) may be particularly sensitive to lead infiltration because they are adjacent to ventricles and areas with semi-permeable blood-brain-barriers. To understand if autonomic nuclei are sensitive to lead accumulation Wistar rats were exposed to lead from the gestational period and lead levels were quantified in brain regions that regulate arterial pressure: the NTS and the HDA. Energy dispersive X-ray fluorescence (EDXRF) was used to quantify total brain lead levels and revealed no differences between exposed and control tissues; measured values were close to the detection limit (2µg/g). Electrothermal atomic absorption spectrometry (ETAAS) was also used, which has a greater sensitivity, to quantify lead. There was ∼2.1µg/g lead in the NTS and ∼3.1µg/g lead in the HDA of exposed rats, and no lead in the control rats. There were greater lead levels in the HDA (∼50%) as compared with the NTS. Pathology studies revealed more prominent lead granules in the HDA as compared with the NTS. Increased microglia and astrocyte activation was also noted in the NTS of lead exposed rats as compared with the HDA. Regional differences in neuro-inflammatory responses likely contribute to heterogeneous lead accumulation, with enhanced clearance of lead in the NTS. Future studies will resolve the mechanisms underpinning tissue-specific lead accumulation.


Assuntos
Hipotálamo/química , Chumbo/análise , Núcleo Solitário/química , Animais , Sistema Nervoso Autônomo/química , Química Encefálica , Feminino , Chumbo/administração & dosagem , Gravidez , Ratos , Ratos Wistar , Espectrometria por Raios X , Espectrofotometria Atômica
13.
Biol Trace Elem Res ; 159(1-3): 233-40, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24763710

RESUMO

Trace elemental content was analysed in edible tissues of Mytilus galloprovincialis collected in five different sampling areas near the mouth of river Tagus estuary in Lisbon. The concentrations of essential elements (S, K, Ca, Fe, Cu, Zn, As, Br and Sr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry, while toxic elements (Cr, Cd, Hg, Se and Pb) were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results show that the essential elements K and S are present at the highest concentrations in all the studied samples reaching 2,920 and 4,520 µg g(-1) (fresh weight), respectively. The highest levels of heavy metals found were in two areas close to the city for Pb and Cd, but below the maximum allowed values.


Assuntos
Metais Pesados/análise , Mytilus/metabolismo , Oligoelementos/análise , Animais , Cádmio/análise , Cromo/análise , Monitoramento Ambiental , Estuários , Chumbo/análise , Mercúrio/análise , Potássio/análise , Rios , Selênio/análise , Análise Espectral
14.
Appl Radiat Isot ; 82: 242-57, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24077395

RESUMO

In the illuminated foral charters commissioned by D. Manuel I, King of Portugal (1495-1521), heraldry played a prominent role. In this work, royal emblems corresponding to the third heraldic design, applied to the Charter of Couto de Teixedo, are studied by means of EDXRF, SEM-EDS, micro-Raman, micro-FTIR and HPLC-DAD to characterize the materials and techniques used to produce this masterpiece of Portuguese Renaissance. By comparing this data with the results previously obtained in other three charters, this research allows for the first time an accurate insight into the reformed manuscripts production, especially since the illuminated charters under consideration were all investigated on the basis of similar micro-spectroscopic techniques. Inks, metal coatings, pigments, organic dyes, fillers or extenders, and binding media are discussed, and their use enlightened by the politic and legal messages the foral charters had to convey. Parchment analysis allowed us to identify the animal species, and all undertaken processes along its preparation. HPLC-DAD allowed us to differentiate the gums used. CaSO4 was observed in the parchment as a degradation product of CaCO3 used in parchment production in the presence of metal sulfates coming from the ink. Pigments used in the different colors as well as some specific phases for some colors were identified. Silvering and gilding processes, metal caratage and silver oxidation compounds were also objects of the present study.

15.
Appl Radiat Isot ; 82: 60-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23954284

RESUMO

The purpose of this work is the elemental mapping of enameled terracotta samples (Zellij), produced between the 13th and 20th centuries in Morocco, collected from five different monuments from Marrakech. These pieces were analyzed by two non-destructive micro X-Ray Fluorescence (XRF) spectrometers, aiming to obtain elemental distribution and elemental composition. From the obtained spectra we have identified the main elements present in the tin-opacified lead glaze. The identification of the decoration colors is based on the different ratios between the fluorescence lines of the main component of the glaze (Pb-Lα line) and the fluorescence lines of the main components of the pigment (Co-Kα, Mn-Kα, Ni-Kα,… lines). The semi-quantitative calculations based on these ratios revealed significant differences between modern and ancient samples.

16.
Genet Mol Res ; 12(3): 2618-24, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23479147

RESUMO

The study of gene expression in plants is fundamental, and understanding the molecular mechanisms involved in important biological processes, such as biochemical pathways or signaling that are used or manipulated in improvement programs, are key for the production of high-quality soybean seeds. Reports related to gene expression of lignin in seeds are scarce in the literature. We studied the expression of the phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase, 4-hydroxycinnamate 3-hydroxylase, and cinnamyl alcohol dehydrogenase genes involved in lignin biosynthesis during the development of soybean (Glycine max L. Merrill) seeds. As the endogenous control, the eukaryotic elongation factor 1-beta gene was used in two biological replicates performed in triplicate. Relative quantitative expression of these genes during the R4, R5, R6, and R7 development stages was analyzed. Real-time polymerase chain reaction was used for the gene expression study. The analyses were carried out in an ABI PRISM 7500 thermocycler using the comparative Ct method and SYBR Green to detect amplification. The seed samples at the R4 stage were chosen as calibrators. Increased expression of the cinnamate-4-hydroxylase and PAL genes occurred in soybean seeds at the R5 and R6 development stages. The cinnamyl alcohol dehydrogenase gene was expressed during the final development phases of soybean seeds. In low-lignin soybean cultivars, the higher expression of the PAL gene occurs at development stages R6 and R7. Activation of the genes involved in the lignin biosynthesis pathway occurs at the beginning of soybean seed development.


Assuntos
Genes de Plantas , Glycine max/metabolismo , Lignina/biossíntese , Sementes/metabolismo , Transcrição Gênica , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Regulação da Expressão Gênica de Plantas , Lignina/genética , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Sementes/crescimento & desenvolvimento , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Transcinamato 4-Mono-Oxigenase/genética , Transcinamato 4-Mono-Oxigenase/metabolismo
17.
Bioelectrochemistry ; 92: 6-13, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23474690

RESUMO

The oxygen reduction due to microaerophilic biofilms grown on graphite cathodes (biocathodes) in Single Chamber Microbial Fuel Cells (SCMFCs) is proved and analysed in this paper. Pt-free cathode performances are compared with those of different platinum-loaded cathodes, before and after the biofilm growth. Membraneless SCMFCs were operating in batch-mode, filled with wastewater. A substrate (fuel) of sodium acetate (0.03 M) was periodically added and the experiment lasted more than six months. A maximum of power densities, up to 0.5 W m(-2), were reached when biofilms developed on the electrodes and the cathodic potential decreased (open circuit potential of 50-200 mV vs. SHE). The power output was almost constant with an acetate concentration of 0.01-0.05 M and it fell down when the pH of the media exceeded 9.5, independently of the Pt-free/Pt-loading at the cathodes. Current densities varied in the range of 1-5 Am(-2) (cathode area of 5 cm(2)). Quasi-stationary polarization curves performed with a three-electrode configuration on cathodic and anodic electrodes showed that the anodic overpotential, more than the cathodic one, may limit the current density in the SCMFCs for a long-term operation.


Assuntos
Fontes de Energia Bioelétrica , Biofilmes/crescimento & desenvolvimento , Aerobiose , Análise da Demanda Biológica de Oxigênio , Carbonato de Cálcio/química , Condutividade Elétrica , Técnicas Eletroquímicas , Eletrodos/microbiologia , Desenho de Equipamento , Grafite/química , Hibridização in Situ Fluorescente , Microscopia Eletrônica de Varredura , Oxirredução , Oxigênio/química , Platina/química , Bactérias Redutoras de Enxofre/crescimento & desenvolvimento , Águas Residuárias/química
18.
Talanta ; 86: 442-6, 2011 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-22063564

RESUMO

An ultrasonic assisted solid-liquid extraction method was developed to determine the level of lead in the brain and urine of rats. Lead was determined by electrothermal atomic absorption spectrometry with longitudinal-Zeeman background correction. Several analytical drawbacks were addressed and overcome, namely small brain sample mass and the formation of precipitate in the urine samples. Utrasonication provided by an ultrasonic probe succeeded in extracting lead from brain samples. Furthermore, it was demonstrated that the formation of a precipitate lowered the lead content in the liquid phase of the urine. Lead was back extracted from the precipitate to the liquid phase with the aid of ultrasonic energy and acidifying the urine with 10% v/v nitric acid. A microwave-assisted acid digestion protocol was used to check the completeness of the lead extraction. The within bath and between bath precision was 5% (n=9) and 7% (n=3) respectively. The limit of quantification was 1.05 µg g(-1) for brain samples and 2.1 µg L(-1) for urine samples. A total of 6 samples of urine and 12 samples of brain from control rats and another 6 samples of urine and 12 samples of brain from rats fed with tap water rich in lead acetate were used in this research. Lead levels in brain and urine from exposed rats ranged from 1.9 ± 0.2 µg g(-1) to 3.5 ± 0.2 µg g(-1) and from 752 ± 56 µg L(-1) to 60.9 ± 1.2 mg L(-1) respectively. Statistically significant differences of levels of lead in brain and urine were found between exposed and non exposed rats.


Assuntos
Química Encefálica , Chumbo/química , Chumbo/urina , Sonicação/métodos , Animais , Ratos , Espectrofotometria Atômica/métodos
19.
Microsc Microanal ; 17(5): 702-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21888755

RESUMO

In this work, we present the results of an analytical method developed for detailed pigment identification, stratigraphy, and degradation of the paint layers of mural paintings applied in the study of the 17th century frescoes from the Misericordia Church of Odemira (Southwest Portugal). In situ X-ray fluorescence spectrometry analyses were performed on three panels of the mural paintings and complemented by colorimetric measurements. The different color areas were also sampled as microfragments (approx. 1 mm2) that were studied as taken or mounted in epoxy resin to expose the different paint layers. The microfragments of paint layers and their cross sections were characterized by optical microscopy and scanning electron microscopy coupled with energy dispersive X-ray spectrometry. Furthermore, elemental analysis was obtained with spatially resolved confocal synchrotron radiation µ-X-ray fluorescence spectrometry performed at ANKA synchrotron FLUO beamline. Occasionally, phase analysis by µ-X-ray diffraction was also performed. Results from the different techniques allowed pigment identification and, in some cases, the evaluation of color changes due to degradation processes and, considering the Southern Portugal geology, the identification of their possible provenance. The pigments used were essentially yellow, brown and red ochres, smalt blue, copper green, and black earths, probably from local sources.

20.
Neurol Sci ; 32(6): 1223-31, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21948057

RESUMO

Urinary disorders are uncommon in the initial phases of multiple sclerosis, but increase in frequency as the disease progresses, with a negative impact on quality of life. The goal of this study was to propose a protocol for the diagnosis and treatment of urinary disorders in multiple sclerosis, based on data from the scientific literature and the experience of Italian clinical centres. In particular, the following clinical aspects were considered: what to do with patients with asymptomatic multiple sclerosis; what to do with symptomatic patients; how and when to perform a second-level diagnostic evaluation; and how to treat urinary disorders. A diagnostic-therapeutic algorithm is proposed, that can be applied in Italian clinical centres.


Assuntos
Consenso , Gerenciamento Clínico , Esclerose Múltipla/complicações , Doenças da Bexiga Urinária , Humanos , Itália , Doenças da Bexiga Urinária/diagnóstico , Doenças da Bexiga Urinária/etiologia , Doenças da Bexiga Urinária/terapia
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