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1.
Proc Natl Acad Sci U S A ; 121(23): e2312173121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38805287

RESUMO

The year 2021 marked a decade of holopelagic sargassum (morphotypes Sargassum natans I and VIII, and Sargassum fluitans III) stranding on the Caribbean and West African coasts. Beaching of millions of tons of sargassum negatively impacts coastal ecosystems, economies, and human health. Additionally, the La Soufrière volcano erupted in St. Vincent in April 2021, at the start of the sargassum season. We investigated potential monthly variations in morphotype abundance and biomass composition of sargassum harvested in Jamaica and assessed the influence of processing methods (shade-drying vs. frozen samples) and of volcanic ash exposure on biochemical and elemental components. S. fluitans III was the most abundant morphotype across the year. Limited monthly variations were observed for key brown algal components (phlorotannins, fucoxanthin, and alginate). Shade-drying did not significantly alter the contents of proteins but affected levels of phlorotannins, fucoxanthin, mannitol, and alginate. Simulation of sargassum and volcanic ash drift combined with age statistics suggested that sargassum potentially shared the surface layer with ash for ~50 d, approximately 100 d before stranding in Jamaica. Integrated elemental analysis of volcanic ash, ambient seawater, and sargassum biomass showed that algae harvested from August had accumulated P, Al, Fe, Mn, Zn, and Ni, probably from the ash, and contained less As. This ash fingerprint confirmed the geographical origin and drift timescale of sargassum. Since environmental conditions and processing methods influence biomass composition, efforts should continue to improve understanding, forecasting, monitoring, and valorizing sargassum, particularly as strandings of sargassum show no sign of abating.


Assuntos
Biomassa , Sargassum , Sargassum/química , Ecossistema , Jamaica , Estações do Ano , Erupções Vulcânicas
2.
Sci Total Environ ; 918: 170354, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38307276

RESUMO

The bioenergetic status of fishes has been used to study their physiological responses to temporal changes at interannual scales. We evaluated the physiological responses of swordfish at an interannual scale from the El Niño Southern Oscillation (ENSO): warm phase "El Niño" in 2015 to the cold phase "La Niña" in 2017 and under neutral conditions as well in 2019. Herein, muscle samples from females and males were analyzed to evaluate the bioenergetic status from their biochemical constituents (L: lipids, P: proteins and G: glucose, E: total energy, and FAs: fatty acid profile), elemental composition (C: carbon, N: nitrogen, H: hydrogen), and nutritional indices (L:P, C:N, DHA/C18:1n-3, DHA/C16:0 and ω3/ω6 FAs). The physiological response of swordfish showed an interaction between the year and sex. Herein, the L and E showed similar trends, with the lowest female values found in 2015 and the highest in 2019. Contrary, males showed their highest values in 2015 and lowest in 2019. FA profile differed among years and highlighted significant differences between females and males in 2019. Although the female L:P and C:N ratios were lower in 2015 than in 2017, a decreasing trend in these ratios was found from 2017 to 2019. Moreover, DHA/C18:1n-3, DHA/C16:0 and ω3/ω6 showed higher ratios in females than males in 2019. Our results coincide with the beginning of the ENSO phases; it is therefore likely that the swordfish diet changed in response to the disturbances in environmental conditions. Furthermore, the degree of individual dietary specialization found under the neutral conditions could indicate differences in the feeding behaviors of males vs. females, which may be an adaptive strategy in this species. These findings will aid in understanding the bioenergetic status of swordfish under different climatic scenarios and the current global warming, providing relevant information for the management of this resource.


Assuntos
El Niño Oscilação Sul , Perciformes , Animais , Masculino , Feminino , Oceano Pacífico , Aquecimento Global , Peixes
3.
Braz. j. biol ; 84: e270501, 2024. tab
Artigo em Inglês | VETINDEX | ID: biblio-1439666

RESUMO

Over the decades, riverine ecosystems is suffering from intense human intervention resulting in degradation and habitat loss as a consequence, many fish species become endangered, particularly in rivers where heavy demand is placed on freshwater. Wallago attu is fast growing catfish belongs to the family siluridae has good market demand having high protein content and nutritional value in it's flesh. The data was obtained for metal concentration in wet and dry body weight in wild Wallago attu. All metal was found under permissible limit as recommended by different international organizations. Calcium was found highest, while cadmium in lowest concentration. Fe, Zn, Cu, Ni, Mn, K, Na, Ca and Mg showed highly significant (P<0.001) positive correlation with wet body weight except Co and Cd showed non-significant (P>0.05) correlation. Metals such as Fe, Cu, Zn, Cd, Pb, K, Ca, Mg and Co shown negative allometric pattern with increasing body weight concentration of Cu, Fe, Zn, Ni, Pb, Mn, Na, Ca and K showed positive relationship (P<0.001) with total length (cm), except for Co and Cd, which indicated non significant correlation (P>0.05). Present Study will helpful to assess toxicity due to presence of heavy metals for researchers and different organizations from River Chenab, Punjab, Pakistan.


Ao longo das décadas, os ecossistemas ribeirinhos sofreram intensa intervenção humana, resultando em degradação e perda de habitat. Como consequência, muitas espécies de peixes tornaram-se ameaçadas, principalmente em rios onde há grande demanda de água doce. Wallago attu é um bagre de crescimento rápido pertencente à família Siluridae tem boa demanda de mercado com alto teor de proteína e valor nutricional em sua carne. Os dados foram obtidos para concentração de metal no peso corporal úmido e seco em Wallago attu selvagem. Todo o metal foi encontrado no limite permitido, conforme recomendado por diferentes organizações internacionais. O cálcio foi encontrado em maior concentração, enquanto o cádmio em menor concentração. Fe, Zn, Cu, Ni, Mn, K, Na, Ca e Mg apresentaram correlação positiva altamente significativa (P < 0,001) com o peso corporal úmido, exceto Co e Cd que apresentaram correlação não significativa (P > 0,05). Metais como Fe, Cu, Zn, Cd, Pb, K, Ca, Mg e Co apresentaram padrão alométrico negativo com o aumento do peso corporal(P < 0,001) e do comprimento total (em centímetros), exceto para Co e Cd, que indica correlação não significativa (P > 0,05). O presente estudo será útil para avaliar a toxicidade devido à presença de metais pesados para pesquisadores e diferentes organizações de River Chenab, Punjab, Paquistão.


Assuntos
Animais , Peixes-Gato , Intoxicação por Metais Pesados/veterinária , Paquistão
4.
Braz. j. biol ; 84: e259731, 2024. tab
Artigo em Inglês | VETINDEX | ID: biblio-1374692

RESUMO

Juglans regia L. are nutritious fruit bearing plants mostly found in Northern areas of Pakistan. The population of walnuts was explored from district Dir and Swat Khyber Pakhtunkhwa, Pakistan for their geographical, climatic and chemical divergence. The geographical differences such as altitude, latitude and longitude whereas climatic differences viz. soil EC, soil pH, precipitations, intensity of light, temperature and soil temperature. In both districts TPC ranged from 211.2±0.6 to 227.8±0.4 mg/100g, RSA ranged from 43.32±1.5% to 52.18±0.4%, conductivity ranged from 296.43±0.6 to 312.22±0.3 S/m and elemental composition such as iron, copper, calcium, zinc and magnesium in Dir differs from 0.312±0.032, 0.209±0.13, 20.0±0.313, 0.406±0.10 and 10.2±0.030 mg/L to 0.543±0.65, 0.698±0.82, 28.7±0.234, 0.685±0.15 and 17.6±0.015 mg/L respectively. Altitude and temperature showed a correlation with total phenolics contents and radical scavenging activity while soil pH, precipitations, soil temperature, soil Ec and light intensity indicated a weak correlation with chemical traits of walnuts. Further studies of walnuts are needed to explore their therapeutically important phytochemicals to succeed naturally pharmaceutical nutrients of the maximum significance for the health of human beings.


Juglans regia L. são plantas frutíferas nutritivas encontradas nas áreas do norte do Paquistão. A população de nozes foi explorada do distrito de Dir e Swat, Khyber Pakhtunkhwa, Paquistão por sua divergência geográfica, climática e química. As diferenças geográficas, como altitude, latitude e longitude, enquanto as diferenças climáticas viz. Ec do solo, pH do solo, precipitações, intensidade de luz, temperatura e temperatura do solo. Em ambos os distritos, o TPC variou de 211,2±0,6 a 227,8±0,4 mg/100g, o RSA variou de 43,32±1,5% a 52,18±0,4%, a condutividade variou de 296,43±0,6 a 312,22±0,3 S/m e composição elementar como ferro, cobre, cálcio, zinco e magnésio em Dir difere de 0,312±0,032, 0,209±0,13, 20,0±0,313, 0,406±0,10 e 10,2±0,030 mg/L a 0,543±0,65, 0,698±0,82, 28,7±0,234, 0,685±0,15 e 17,6±0,015 mg/L respectivamente. A altitude e a temperatura mostraram correlação com os teores de fenólicos totais e atividade de eliminação de radicais, enquanto o pH do solo, precipitações, temperatura do solo, Ec do solo e intensidade de luz indicaram uma correlação fraca com características químicas das nozes. Mais estudos de nozes são necessários para explorar seus fitoquímicos terapeuticamente importantes para obter naturalmente nutrientes farmacêuticos de máxima importância para a saúde dos seres humanos.


Assuntos
Nutrientes , Juglans/crescimento & desenvolvimento , Fitoterapia , Nozes/crescimento & desenvolvimento , Paquistão
5.
Food Res Int ; 174(Pt 1): 113491, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37986494

RESUMO

The microstructural changes in papaya tissue during calcium diffusion, the effect on drying kinetics and texture parameters were investigated. Calcium pretreatment was applied to papaya samples for 3 h, at a solution concentration of 1.5 g Ca(OH)2/100 mL H2O, and a solution temperature of 25 °C; subsequently, the samples were convectively dried at 70 °C, air flow of 1.5 m/s, and a relative humidity of 5 ± 2%. Calcium content was determined using the Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) technique, the microstructure of the samples was analyzed by High-Resolution Scanning Electron Microscopy (HR-SEM), and the elementary analysis was performed by Energy-Dispersive X-ray Spectroscopy (EDS). Effective diffusivity of calcium (DefCa) and moisture (Defw) were calculated during pretreatment and drying, respectively and texture parameters were determined by double compression using a texturometer. The transport mechanism determined during calcium pretreatment was diffusion with a DefCa = 3.10 × 10-10 m2/s. Also, branched calcium microstructures in the cell walls of tissue were observed due to the calcium effect, it was supported by elemental analysis, which showed an increase of calcium in section restructured compared to non-restructured. During drying, Defw = 1.86 × 10-9 m2/s was higher in pretreated compared to non-pretreated samples with Defw = 1.17 × 10-9 m2/s, indicating a higher drying rate and moisture loss. The texture values changed significantly (α ≤ 0.05) due to calcium pretreatment and drying; the calcium microstructures caused higher cohesiveness, springiness, gumminess, and chewiness. Calcium modifies the microstructure and composition of papaya tissue; therefore, drying kinetics and texture parameters depend on this modification.


Assuntos
Cálcio , Carica , Dessecação/métodos , Temperatura , Difusão , Cálcio da Dieta
6.
Food Res Int ; 163: 112258, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36596169

RESUMO

In this study the effect of the direct application of different concentrations of boron in grape bunches on the phytochemical composition of grapes and wine was evaluated. The experiment was carried out by direct application to the grape bunch of different concentrations (0, 1.0, 2.0, 4.0 and 8.0 g/L) of boron solution, in two consecutive vintages, 2018 and 2019. The wines were elaborated by the same microvinification method. Histological analyzes by optical microscopy and phenolic profile by HPLC-DAD were performed on the grapes. The wines were analyzed by HPLC-DAD and ICP-MS for phenolic profile and elemental composition, respectively. Histological analyzes of the grape skin showed an increase in the presence of polyphenols in the cellular tissue of grapes treated with different concentrations of boron when compared to the control samples in both vintages. The addition of boron influenced the phenolic profile of the grapes, resulting in an increase in the content of anthocyanins and flavanols. Regarding to wines, the treatment of grapes by direct application of boron significantly influenced the chemical composition of wines. In 2018, the application of 2 g/L of boron showed a significant increase in the concentration of malvidin and delphinidin in wines. The application of 1 g/L showed the highest concentration of malvidin, delphinidin and peonidin in the 2019 vintage. The boron content increased in the wine samples according to the boron concentrations applied to the grape. Thus, it is possible to produce chemically distinct wines with the direct application of boron to the grapes.


Assuntos
Vitis , Vinho , Vitis/química , Vinho/análise , Antocianinas/análise , Boro/análise , Frutas/química , Polifenóis/análise , Fenóis/análise , Compostos Fitoquímicos/análise
7.
Biol Trace Elem Res ; 201(9): 4590-4599, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36550265

RESUMO

In this work, microwave-induced plasma optical emission spectrometry was applied for multielement determination in South American wine samples. The analytes were determined after acid digestion of 47 samples of Brazilian and Argentinian wines. Then, logistic regression, support vector machine, and decision tree for exploratory analysis and comparison of these algorithms in differentiating red wine samples by region of origin were carried out. All wine samples were classified according to their geographical origin. The quantification limits (mg L-1) were P: 0.06, B: 0.08, K: 0.17, Mn: 0.002, Cr: 0.002, and Al: 0.02. The accuracy of the method was evaluated by analyzing the wine samples by ICP OES for results' comparison. The concentrations in mg L-1 found for each element in wine samples were as follows: Al (< 0.02-1.82), Cr (0.15-0.50), Mn (< 0.002-0.8), P (97-277), B (1.7-11.6), Pb (< 0.06-0.3), Na (8.84-41.57), and K (604-1701), in mg L-1.


Assuntos
Oligoelementos , Vinho , Vinho/análise , Espectrometria de Massas/métodos , Inteligência Artificial , Análise Espectral/métodos , Brasil , Oligoelementos/análise
8.
Food Res Int ; 162(Pt B): 112144, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461365

RESUMO

This work presents the enrichment of powdered dairy compounds with soy extract, and the determination of its physical properties, rehydration characteristics, multielement profile, and polyphenolic potential. Five dairy compound formulations were developed, where milk powder was replaced by 10, 20, 30, 40, and 49 % w/w of soy extract.. Multivariate analyzes using combined PCA analyzes were used to group the samples and, thus, reveal the main characteristics associated with their physicochemical properties, bioactive composition, and multi-element profile. The protein content in the samples was not significantly affected by the addition of soy extract. There was a gradual increase in the total fat as the concentration of soy extract increased. Furthermore, with the increase in the percentage of soy extract in the dairy compounds, there was an increase in the levels of total polyphenols, total flavonols, and antioxidant capacity, and of some minerals, such as Fe, Mn, P, Cu, and Mg. The DC49 sample showed the highest values for total polyphenols (178.65 mg of gallic acid (GAE)/100 g) and total flavonols (1.51 mg of catechin/100 g). The addition of soy extract promoted the enrichment of important minerals in the samples, with an increase of up to 55 times in the Fe content and up to 40 times in the Mn content. Physical properties (density and fluidity) and rehydration properties (wetting, dispersibility, and solubility) also were affected as the percentage of soy extract in the samples increased. When there was an addition of up to 20 % soy extract, the samples are still wettable. All dairy compounds showed solubility above 69 %. The use of soy extract in the polyphenolic and mineral enrichment of the dairy compounds is important to add nutritional value to powdered milk, we emphasize that this product has enormous potential to be used in diets that require mineral supplementation.


Assuntos
Fabaceae , Glycine max , Pós , Hidratação , Flavonóis , Polifenóis , Extratos Vegetais
9.
Animals (Basel) ; 12(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35739813

RESUMO

Farmed salmonids show alterations in bone structure that result in skeletal deformities during formation, repair, and regeneration processes, with loss of mineralization at the level of the axial skeleton, mainly the head and spine, affecting their quality of life and even causing death. Despite improving factors, such as farming conditions, diets, and genetics, bone alterations appear more frequently in farmed fish than in wild fish. Thus, we used SEM-EDX, and TGA-DSC to study bone mineralization in farmed and wild rainbow trouts. As expected, we found significant differences in the nutritional parameters of farmed and wild fish (p < 0.05). Microstructural analyses indicated that farmed fish have a more robust mineral structure (p < 0.05), confirming the differences in mineralization and microstructure between both groups. However, the mechanisms regulating absorption and distribution in the organism and their effect on bone mineralization remain to be known. In our study, the combined use of techniques such as SEM-EDX and TGA-DSC allows a clearer assessment and detailed characterization beneficial to understanding the relationship between diet control and bone microstructure.

10.
Food Chem ; 390: 133148, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35551027

RESUMO

This study aimed to evaluate the piperine content, essential oil composition, and multi-elemental composition of black pepper samples according to different drying methods and harvest season. Differences in essential oil composition and B, Ca, K, Mg, and S were noted according to sampling campaign, indicating secondary metabolism plant alterations. Mechanical drying resulted in essential oil composition changes due to high temperature exposure during processing. Increases in Fe and Cr contents when employing mechanical dryers with direct heating were also observed, due to direct contact with metallic structures and particulate material from the burning process. The As and Pb contents of several samples were higher than the maximum permissible limits, reaching 0.46 and 0.56 mg kg-1, respectively, thus surpassing legislation safety limitations for human consumption.


Assuntos
Óleos Voláteis , Piper nigrum , Alcaloides , Benzodioxóis , Humanos , Óleos Voláteis/química , Piper nigrum/química , Piperidinas , Alcamidas Poli-Insaturadas/química , Estações do Ano
11.
Braz. arch. biol. technol ; Braz. arch. biol. technol;65: e22210592, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364446

RESUMO

Abstract The sewage sludge (SS) use in agriculture has been limited by the Brazilian legislation to a few situations, mainly as a precautionary measure due to inorganic pollutants and pathogens. Thus, a large amount of SS has been accumulated in landfills, with no prospect of use, generating great concern for governments and society. Thermal treatment via pyrolysis has stood out as an option for SS recycling, transforming it into a carbon-rich product known as SS biochar (SSB). Biochar from SS showed good potential to be used for agricultural and environmental purposes. The present study aimed to evaluate the influence of pyrolysis at 300°C on the physical, chemical, morphological and mineralogical characteristics of SSB. In general, pyrolysis increased total carbon, total nitrogen, macro and micronutrient contents, except potassium. Pyrolysis also increased heavy metals (HMs) concentration in SSB. However, HMs values remained below the maximum limits allowed according to the legislation on SS agricultural use. X-ray analysis showed that both SS and SSB present silica (SiO2) as the main mineral. Pyrolysis also increased the SS surface area (SA) and porosity. In general, results of the present study prove showed that pyrolysis is a technological alternative to enable SS use as a sustainable input in agriculture.

12.
Acta amaz ; 52(1): 13-22, 2022. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1437340

RESUMO

Forest fires incorporate pyrogenic organic matter into the soil, affecting the characteristics of soil organic matter (SOM) due to its high aromaticity, increasing its renewal time. However, the factors that control the concentration of pyrogenic organic matter and its chemical composition and structure are still little known. Forest fragments dispersed in a savanna matrix of the northern Brazilian Amazon are frequently impacted by fires, which can affect the composition of SOM within the fragments. The aim of this study was to analyse the chemical composition of SOM in the border and interior of six forest fragments in the Roraima savanna, in the northern Brazilian Amazon. Soil samples were collected at 10-cm intervals up to 1 m in depth at the border and in the interior of each fragment. Soil organic material concentration was determined with 10% HF solution and its elemental composition, thermogravimetric index, and 13C CPMAS NMR spectroscopic analysis were determined. There was no significant difference in the aromaticity index between border and interior. The concentration of alkyl C structures between border (22 to 25%) and interior (19 to 29%) indicated the occurrence of medium-intensity fires in the study area. The thermogravimetric analysis showed no significant difference in the thermal stability of SOM between border and interior. Our results showed no pronounced difference in SOM quality up to 1 m depth between the border and the interior of the evaluated forest fragments, indicating that this compartment is stable throughout the fragments.(AU)


Incêndios florestais incorporam matéria orgânica pirogênica ao solo, afetando as características da matéria orgânica do solo (MOS), devido a sua alta aromaticidade. Porém, os fatores que controlam a composição química e a estrutura da matéria orgânica pirogência ainda são pouco conhecidos. Fragmentos florestais dispersos em uma matriz de savana na Amazônia setentrional brasileira são freqüentemente impactados por incêndios, que podem afetar a composição da MOS nos fragmentos. O objetivo deste estudo foi analisar a composição química da MOS na borda e no interior de seis fragmentos florestais situados na savana de Roraima, norte da Amazônia brasileira. Amostras de solo foram coletadas em intervalos de 10 cm até 1 m de profundidade na borda e no interior de cada fragmento. A concentração da MOS foi determinada com solução de HF a 10% e sua composição elementar, índice termogravimétrico e análise espectroscópica de 13C CPMAS RMN foram determinados. Não houve diferença significativa no índice de aromaticidade entre borda e interior. A concentração de estruturas alquil C entre a borda (22 a 25%) e o interior (19 a 29%) indicou a ocorrência de incêndios de média intensidade na área de estudo. A análise termogravimétrica não mostrou diferença significativa na estabilidade térmica da matéria orgânica do solo entre a borda e o interior. Nossos resultados não mostraram diferença pronunciada na qualidade da MOS até 1 m de profundidade entre a borda e o interior dos fragmentos florestais avaliados, indicando que este compartimento é estável ao longo dos fragmentos.(AU)


Assuntos
Qualidade do Solo , Incêndios Florestais , Matéria Orgânica , Brasil
13.
Int. j. odontostomatol. (Print) ; 15(2): 381-386, jun. 2021. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1385772

RESUMO

Los instrumentos rotatorios utilizados en el tratamiento de conductos dentales necesitan cumplir con ciertas características físicas que le confieran un uso correcto, adecuado y seguro para su uso clínico. En el mercado comercial existen una serie de instrumentos importados que dejan en duda la autenticidad de estos debido a sus bajos costos. En este estudio evaluamos física, química y morfológicamente dos kits de instrumentos rotatorios Protaper universal (Dentsply) mediante análisis de MEB, EDX, microdureza y EDS. Uno de los kits (grupo 1) se adquirió directamente de la casa comercial y otro kit importado que a simple vista no parecía cumplir con los estándares de calidad de un correcto empaquetado (grupo 2). En el análisis de MEB se observaron características morfológicas muy diferentes entre ambos kits, el grupo 2 presentó diversas irregularidades en la superficie de las limas, sin embargo, en el EDS no se encontró diferencia alguna. En cuanto al análisis de microdureza se observó una estadística estadísticamente significativa y en el EDS se observaron mayores picos de intensidad en cuanto a la aleación de Ni-Ti en el grupo 2. Estos resultados sugieren que existen instrumentos rotatorios importados que a pesar de su bajo costo pueden presentar ciertas características muy similares a los kits auténticos, sin embargo, física y químicamente pueden resultar en un riesgo para su uso clínico debido a la diferencia entre estos.


Rotatory files are instruments used in the treatment of dental canals roots. These instruments need to comply with certain physical characteristics for a correct, adequate and safe use for clinical use. In the commercial market there are a series of imported instruments that cast doubt on their authenticity due to their low costs. In this study we physically, chemically and morphologically evaluated two Protaper universal rotary instrument kits (Dentsply) using SEM, EDX, microhardness and EDS analysis. One of the kits (group 1) was purchased directly from the commercial house and another imported kit that a simple view did not seem to meet the quality standards of a correct packaging (group 2). In the SEM analysis, very different morphological characteristics were observed between both kits, group 2 presented various irregularities on the surface of the files, however, no difference was found in the EDS. Regarding the microhardness analysis, a statistically significant statistic was observed and in the EDS, higher intensity peaks were observed in terms of the Ni-Ti alloy in group 2. These results suggest that there are imported rotary instruments that despite their low cost can present characteristics very similar to authentic kits, however, physically and chemically they can result in a risk for their clinical use due to the difference between them.


Assuntos
Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/instrumentação , Instrumentos Odontológicos , Rotação , Espectrometria por Raios X , Teste de Materiais , Preparo de Canal Radicular/instrumentação , Desenho de Equipamento
14.
Environ Monit Assess ; 192(5): 313, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32333116

RESUMO

Four monitoring campaigns between the years 2009 and 2018 were conducted in Córdoba City, Argentina, to detect toxic metals in PM2.5 samples. The concentrations of As, Cd, Pb, Cu, Cr, Mn, Hg, Ni, and Zn, together with several other elements, were measured. The average metal concentrations followed the order: Zn > Cr > Cu > Mn > Pb > V > Ni > As ~ Sb > Cd > Tl > Pd > Hg > Pt. From the analysis of the temporal variation in the elemental concentration of PM2.5, results show seasonal variations that reach, in general, a maximum in the coldest seasons and a minimum in the warmer seasons. These differences could be explained by the different weather conditions during each season, the influence of the El Niño/La Niña regimen, and the presence of fires on certain sampling dates. The source apportionment analysis performed for the period 2017-2018 showed the contribution to PM2.5 of combustion of heavy fuel oil and diesel-powered vehicles, pet coke, metallurgical and nonferrous industries, paint plant factory, traffic, and natural sources like the soil and road dust. This last analysis completed the assignment of sources for the 10-year period of study. Thus, the results of this work contribute to the implementation of emission reduction strategies in order to decrease the impact of PM2.5 on the environment and the human health.


Assuntos
Poluentes Atmosféricos , Metais Pesados , Argentina , Cidades , Poeira , Monitoramento Ambiental , Humanos , Material Particulado
15.
Toxicol Res ; 36(2): 139-148, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32257926

RESUMO

Several studies have pointed to fine particulate matter (PM2.5) as the main responsible for air pollution toxic effects. Indeed, PM2.5 may not only cause respiratory and cardiovascular abnormalities but it may also affect other organs such as the liver. Be that as it may, only a few studies have evaluated the PM2.5 effects on hepatic tissue. Moreover, most of them have not analyzed the relationship between particles composition and toxicological effects. In this study, healthy rats were subjected to urban levels of PM2.5 particles in order to assess their structural and functional effects on the liver. During the exposure periods, mean PM2.5 concentrations were slightly higher than the value suggested by the daily guideline of the World Health Organization. The exposed rats showed a hepatic increase of Cr, Zn, Fe, Ba, Tl and Pb levels. This group also showed leukocyte infiltration, sinusoidal dilation, hydropic inclusions and alterations in carbohydrates distribution. These histologic lesions were accompanied by serological changes, such as increase of total cholesterol and triglycerides, as well as genotoxic damage in their nuclei. We also observed significant associations between several biomarkers and PM2.5 composition. Our results show that exposure to low levels of PM2.5 might cause histologic and serological changes in liver tissue, suggesting that PM2.5 toxicity is influenced not only by their concentration but also by their composition and the exposure frequency.

16.
Data Brief ; 29: 105121, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31993471

RESUMO

The data set presented here offers evidence of the elemental composition related to a SEM micrograph of [Mn5(PO3(OH))2(PO4)2⋅4H2O] (MnPhos) powders, known as hurealite, and synthesized by the reflux method. In addition, it contains additional information of the glass transition, melting and decomposition temperatures and their weight loss percent of coatings based on MnPhos incorporated into waterborne poly(urethane) (WPU). These data are complementing of the article "Corrosion investigation of new hybrid organic/inorganic coatings for carbon steel substrates: electrochemical and surface characterizations".

17.
Rev. bras. zootec ; 49: e20190214, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1443581

RESUMO

Our aim was to assess the mineral composition of corn silages produced in four states of Brazil: Goiás, Minas Gerais, Paraná, and Santa Catarina. In total, seventy-three samples were analyzed. Total element content was extracted by HNO3 and H2 O2 microwave-assisted digestion, and inductively coupled plasma-mass spectrometry (ICP-MS) was used to determine concentration. Of the 31 elements analyzed (Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Se, Sr, Ti, Tl, U, V, and Zn), 21 had concentrations above equipment detection limits. No elements reached the maximum tolerable concentration, but concentrations of Ca (0.14-0.15%), Cu (3.4-5.6 mg kg−1), P (0.13-0.16%), S (0.06-0.08%), and Zn (13-19 mg kg−1) were below the adequate concentration for good nutritional balance. The strong and consistent correlation observed between Fe and Ti in silage samples indicated contamination by soil. Mean concentrations of Cu, Mn, Mo, P, S, and Zn were different among states, and canonic analyses successfully discriminate samples according to their state of origin. Minerals from corn silage should be considered when formulating balanced cattle diets. To ensure silage quality, farmers must adopt strategies that reduce contamination by soil during the ensiling process.(AU)


Assuntos
Silagem/análise , Zea mays/química , Minerais/toxicidade , Brasil
18.
J Sci Food Agric ; 99(10): 4642-4650, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30895630

RESUMO

BACKGROUND: The elemental profile of the Marselan wine cycle was studied with a single ion-beam technique, namely particle-induced X-ray emission (PIXE). Samples were collected from all of the major stages involved in the wine cycle, including soil, vine plant, grape, and different stages of wine processing. RESULTS: The results show the influence of field practices on the elemental composition of leaves, branches, grapes, and soil. Mechanisms of element precipitation and elimination from the wine were identified through the changes in the elemental concentrations measured during the post-harvesting processes. The concentrations of some elements, such as Al, Si, K, and Ni, did not vary for grapes collected at different maturation stages. On the other hand, changes in the concentrations of Si, Cl, Ca, Cu, and K were observed right after the maceration and pressing processes in young wine. Finally, the reduction in the Cu concentration during the last stages of the wine cycle is related to its precipitation in the storage tanks. CONCLUSIONS: It was found that field practices and winemaking processes played distinct roles in the elemental composition of grapes and wine from different preparation stages. Moreover, PIXE proved to be a suitable analytical tool for the analysis of the whole wine cycle because it handles solid and liquid samples in a clean and straightforward manner. © 2019 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Oligoelementos/análise , Vitis/química , Vinho/análise , Frutas/química , Solo/química
19.
Food Chem ; 269: 103-110, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100411

RESUMO

This work aimed to investigate the evolution of phenolic compounds and elements during the aging of Malbec red wines from different regions of Mendoza (Argentina) and California (United States). The profiles of low molecular weight polyphenols and anthocyanins were analyzed using high-performance liquid chromatography with a diode-array detector (HPLC-DAD), and the elemental composition using microwave plasma-Atomic emission spectrometry (MP-AES). Through uni- and multivariate statistical analyses, the effects of aging time and region on wine were investigated. It was observed that aging time was a significant factor that affected the phenolic compound profile in the studied Malbec wines studied and that after five years of aging, the wines could be differentiated according to region. The results of this study may impact decisions made regarding the storage of Malbec wines in the future.


Assuntos
Antocianinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Fenóis/análise , Vitis/química , Vinho/análise , Argentina , California
20.
Artigo em Inglês | MEDLINE | ID: mdl-28644400

RESUMO

Elemental characterization of fine particulate matter was undertaken at schools and residences in three low income neighborhoods in Quito, Ecuador. The three zones were located in the northern (Cotocollao), south central (El Camal), and south east (Los Chillos) neighborhoods and were classified as zones 1-3, respectively. Forty elements were quantified via ICP-MS analysis. Amongst the geogenic elements, the concentration of Si was the most abundant followed by S, Al, and Ca. Elements with predominantly anthropogenic sources such as Zn, V, and Ni were higher in zone 3 school followed by zone 2 and zone 1 schools. Enrichment factors were calculated to study the role of crustal sources in the elemental concentrations. Geogenic elements, except K, all had values <10 and anthropogenic elements such as Ni, V, Zn, Pb, As, Cr had >10. Principal Component Analysis suggested that Ni and V concentrations were strongly attributable to pet coke and heavy oil combustion. Strong associations between As and Pb could be attributed to traffic and other industrial emissions. Resuspended dust, soil erosion, vehicular emissions (tailpipe, brake and tire wear, and engine abrasion), pet coke, heavy oil combustion, and heavy industrial operations were major contributors to air pollution.


Assuntos
Poluentes Atmosféricos/química , Poluição do Ar , Monitoramento Ambiental , Habitação , Material Particulado/química , Instituições Acadêmicas , Poluição do Ar/análise , Poeira/análise , Equador , Tamanho da Partícula , Pobreza , Análise de Componente Principal , Características de Residência , Solo , Emissões de Veículos/análise
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