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1.
Rev. biol. trop ; 71(1)dic. 2023.
Artigo em Espanhol | SaludCR, LILACS | ID: biblio-1514965

RESUMO

Introducción: La gran diversidad de especies maderables tropicales demanda el desarrollo de nuevas tecnologías de identificación con base en sus patrones o características anatómicas. La aplicación de redes neuronales convolucionales (CNN) para el reconocimiento de especies maderables tropicales se ha incrementado en los últimos años por sus resultados prometedores. Objetivo: Evaluamos la calidad de las imágenes macroscópicas con tres herramientas de corte para mejorar la visualización y distinción de las características anatómicas en el entrenamiento del modelo CNN. Métodos: Recolectamos las muestras entre el 2020 y 2021 en áreas de explotación forestal y aserraderos de Selva Central, Perú. Luego, las dimensionamos y, previo a la identificación botánica y anatómica, las cortamos en secciones transversales. Generamos una base de datos de imágenes macroscópicas de la sección transversal de la madera, a través del corte, con tres herramientas para ver su rendimiento en el laboratorio, campo y puesto de control. Resultados: Usamos tres herramientas de corte para obtener una alta calidad de imágenes transversales de la madera; obtuvimos 3 750 imágenes macroscópicas con un microscopio portátil que corresponden a 25 especies maderables. El cuchillo ''Tramontina'' es duradero, pero pierde el filo con facilidad y se necesita una herramienta para afilar, el cúter retráctil ''Pretul'' es adecuado para madera suave y dura en muestras pequeñas de laboratorio; el cuchillo ''Ubermann'' es apropiado para el campo, laboratorio y puesto de control, porque tiene una envoltura duradera y láminas intercambiables en caso de pérdida de filo. Conclusiones: La calidad de las imágenes es decisiva en la clasificación de especies maderables, porque permite una mejor visualización y distinción de las características anatómicas en el entrenamiento con los modelos de red neuronal convolucional EfficientNet B0 y Custom Vision, lo cual se evidenció en las métricas de precisión.


Introduction: The great diversity of tropical timber species demands the development of new technologies capable of identifying them based on their patterns or anatomical characteristics. The application of convolutional neural networks (CNN) for the recognition of tropical timber species has increased in recent years due to the promising results of CNNs. Objective: To evaluate the quality of macroscopic images with three cutting tools to improve the visualization and distinction of anatomical features in the CNN model training. Methods: Samples were collected from 2020 to 2021 in areas of logging and sawmills in the Central Jungle, Peru. They were later sized and, after botanical and anatomical identification, cut in cross sections. A database of macroscopic images of the cross-section of wood was generated through cutting with three different tools and observing its performance in the laboratory, field, and checkpoint. Results: Using three cutting tools, we obtained high quality images of the cross section of wood; 3 750 macroscopic images were obtained with a portable microscope and correspond to 25 timber species. We found the ''Tramontina'' knife to be durable, however, it loses its edge easily and requires a sharpening tool, the ''Pretul'' retractable cutter is suitable for cutting soft and hard wood in small laboratory samples and finally the ''Ubermann'' knife is suitable for use in the field, laboratory, and checkpoint, because it has a durable sheath and interchangeable blades in case of dullness. Conclusion: The quality of the images is decisive in the classification of timber species, because it allows a better visualization and distinction of the anatomical characteristics in training with the EfficientNet B0 and Custom Vision convolutional neural network models, which was evidenced in the precision metrics.


Assuntos
Madeira/análise , Microscopia Eletrônica , Ecossistema Tropical , Peru , Aprendizado de Máquina
2.
Ciênc. rural (Online) ; 52(10): e20200357, 2022. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1396729

RESUMO

This paper examined the regional concentration of native fuelwood production in Rio Grande do Norte, Brazil, between 1990-2017. Information on native fuelwood was gathered from forestry activities collected by the Brazilian Institute of Geography and Statistics (IBGE). This study analyzed the current situation and the spatial distribution of the state's fuelwood production by quartiles. The following indicators were used to measure market concentration: Gini Coefficient (G), Comprehensive Concentration Index (CCI), Herfindahl-Hirschman Index (HHI) and Concentration Ratio [CR(k)]. In Rio Grande do Norte, there was a -2.76% annual decrease in the production of native fuelwood, from 5,280 x10³ m³ (1990) to 777 x10³ m³ (2017). Classification of the municipalities by quartile revealed that most municipalities had low fuelwood production. The G inferred a very strong to absolute inequality for the municipalities and a weak to null inequality for the mesoregions.The CCI demonstrated no market concentration in the municipalities and a regional concentration in the mesoregions. The HHI corroborated the CCI by affirming the presence of a competitive market for the municipalities and microregions and a concentrated market in the mesoregions.The CR(k) of the four largest municipalities indicated a moderately low concentration. This study concluded that there is a competitive market structure for native fuelwood inthe state of Rio Grande do Norte.


Este artigo analisou a concentração regional da produção de lenha nativa do Rio Grande do Norte - Brasil, no período de 1990 a 2017. As informações da lenha nativa foram obtidas da produção da extração vegetal e da silvicultura, disponíveis no Instituto Brasileiro de Geografia e Estatística (IBGE). Analisou a conjuntura, a distribuição espacial da produção de lenha estadual por meio os quartis e mensurou a concentração por meio dos indicadores: Coeficiente de Gini (G), Índice de Concentração Compreensiva (CCI), Índice de Herfindahl-Hirschman (HHI) e Razão de Concentração [CR(k)]. Os resultados mostraram que houve decréscimo de -2,76% a.a. na produção de lenha nativa estadual, partindo de 5.280 x10³ m³ (1990) para 777 x10³ m³ (2017). O quartil municipal revelou que a maioria dos municípios produz pouca lenha; apesar do G ter inferido uma desigualdade muito forte a absoluta para os municípios produtores de lenha e fraca a nula para as mesorregiões, já o CCI mostrou para os municípios que é não concentrado e as mesorregiões tem concentração regional; HHI corroborou com esta afirmação mostrando um mercado altamente competitivo para os municípios e microrregiões e concentrado para as mesorregiões produtoras de lenha; o CR(k) dos quatro maiores municípios foi constatada uma concentração moderadamente baixa. Conclui-se que a lenha nativa do estado do Rio Grande do Norte possui estrutura de mercado competitiva.


Assuntos
Madeira/análise , Florestas , Agricultura Florestal/métodos , Brasil , Zona Semiárida
3.
Pak J Biol Sci ; 24(3): 374-382, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34486323

RESUMO

<b>Background and Objective:</b> <i>Trametes versicolor</i> has not only been valued in medical use but also in environmental protection. One of the major challenges currently faced in the commercial cultivation of <i>T. versicolor</i> is finding superior strains that can produce high yields. In an attempt to search for high-yield potential <i>T. versicolor</i>, two wild strains, namely VNUA and BV, were isolated and evaluated for potential cultivation. <b>Materials and Methods:</b> Optimized culture conditions were set up by one-individual factor-at-a-time. Four different kinds of culture media, including Czapek, Raper, PGA and modified Potato Dextrose Agar (PDA), were investigated to ascertain the optimal media. The efficiency of sawdust and rice grain for mother spawn production was evaluated. Different combinations of sawdust and rice husk were tested to investigate the most favorable substrate mixtures. <b>Results:</b> The ideal medium and temperature for the favorable mycelial growth of <i>T. versicolor</i> were PGA and 30°C, respectively. The optimal spawning material for upscaling of the mycelium was Treatment D (20% rice grain, 79% sawdust and 1% calcium carbonate). The strains were successfully cultivated in a basal substrate combination of sawdust and rice husk supplemented with wheat bran. Investigated strains responded differently to different substrates cultivation. Of note, compared with strain BV, strain VNUA showed a significantly higher biological efficiency (7.3%). <b>Conclusion:</b> Wild <i>T. versicolor</i> strains were successfully fructified under artificial cultivation conditions. Strain VNUA can be considered as a potential strain for commercial cultivation. The use of sawdust for the spawn production of <i>T. versicolor</i> can reduce the cost of manufacturing.


Assuntos
Polyporaceae/isolamento & purificação , Especificidade por Substrato , Madeira/análise , Micélio/crescimento & desenvolvimento , Vietnã
4.
Proc Natl Acad Sci U S A ; 116(36): 17900-17905, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31427536

RESUMO

A comparison of sequenced Agaricomycotina genomes suggests that efficient degradation of wood lignin was associated with the appearance of secreted peroxidases with a solvent-exposed catalytic tryptophan. This hypothesis is experimentally demonstrated here by resurrecting ancestral fungal peroxidases, after sequence reconstruction from genomes of extant white-rot Polyporales, and evaluating their oxidative attack on the lignin polymer by state-of-the-art analytical techniques. Rapid stopped-flow estimation of the transient-state constants for the 2 successive one-electron transfers from lignin to the peroxide-activated enzyme (k2app and k3app ) showed a progressive increase during peroxidase evolution (up to 50-fold higher values for the rate-limiting k3app ). The above agreed with 2-dimensional NMR analyses during steady-state treatments of hardwood lignin, showing that its degradation (estimated from the normalized aromatic signals of lignin units compared with a control) and syringyl-to-guaiacyl ratio increased with the enzyme evolutionary distance from the first peroxidase ancestor. More interestingly, the stopped-flow estimations of electron transfer rates also showed how the most recent peroxidase ancestors that already incorporated the exposed tryptophan into their molecular structure (as well as the extant lignin peroxidase) were comparatively more efficient at oxidizing hardwood (angiosperm) lignin, while the most ancestral "tryptophanless" enzymes were more efficient at abstracting electrons from softwood (conifer) lignin. A time calibration of the ancestry of Polyporales peroxidases localized the appearance of the first peroxidase with a solvent-exposed catalytic tryptophan to 194 ± 70 Mya, coincident with the diversification of angiosperm plants characterized by the appearance of dimethoxylated syringyl lignin units.


Assuntos
Evolução Biológica , Fungos/genética , Lignina/metabolismo , Peroxidase/genética , Plantas/metabolismo , Plantas/microbiologia , Madeira/metabolismo , Madeira/microbiologia , Catálise , Fungos/enzimologia , Hidrólise , Cinética , Lignina/análise , Oxirredução , Peroxidase/metabolismo , Plantas/genética , Madeira/análise
5.
Mar Pollut Bull ; 141: 119-126, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955716

RESUMO

The amount and composition of beach litter was assessed, during spring 2018, at 56 sites along the coast of Alicante Province, on the western Mediterranean Sea. Selected sites covered "natural" (19), "village" (17) and "urban" (20) bathing areas and a total of 10,101 litter items was counted in an area of 201,686 m2. Plastic represented the dominant material with 8345 items, i.e. 82.6% of all debris; paper and cardboard numbered 566 items (i.e. 5.6%); pottery and ceramics 348 (3.4%); metal 325 (3.2%); cloth 231 (2.3%); glass 147 (1.5%); rubber 64 (0.6%); wood 46 (0.5%) and other materials summed 29 items, i.e. 0.3% of all debris. Cigarette butts, 45.6% of total items, were observed at different coastal sites: i.e. 1028 units at natural, 1148 at village and 2431 at urban sites. Despite the efforts of local administrations, which enforced cleaning operations at most sites, litter items were essentially related to beachgoers followed by wastewater discharges and fishing activities.


Assuntos
Praias/normas , Monitoramento Ambiental/métodos , Resíduos/análise , Vidro/análise , Mar Mediterrâneo , Estações do Ano , Espanha , Águas Residuárias/análise , Madeira/análise
6.
Radiat Prot Dosimetry ; 185(3): 331-342, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30806459

RESUMO

This work evaluates the 137Cs and 90Sr content of wood pellets of the Greek energy market and additionally calculates worker exposure in Greek catering establishments (rotisseries). Wood pellets and ash samples were analysed through high resolution gamma-ray spectroscopy and liquid scintillation. Imported pellets had higher 137Cs concentrations, especially pellets that were imported in bulk. Greek pellets had very smaller 137Cs amounts. Despite the high variation in 137Cs content the 137Cs exemption levels were not exceeded in any case. However, if an enrichment factor of 300 is assumed, some ashes samples may exceed 13000 Bq/kg. The highest amounts of 90Sr were measured in ashes from pellets manufactured abroad in 2015, with up to 1060 Bq/kg. A linear regression model of the ratio of 137Cs to 90Sr activity followed our data well, and other sets of data partially. A dosimetry assessment of kitchen employees revealed that maximum possible dose intake reached 400 nSv/year.


Assuntos
Poluentes Ocupacionais do Ar/análise , Radioisótopos de Césio/análise , Exposição por Inalação/análise , Exposição Ocupacional/análise , Radiometria/métodos , Radioisótopos de Estrôncio/análise , Madeira/análise , Manipulação de Alimentos , Humanos
7.
Sci Total Environ ; 663: 170-176, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30711583

RESUMO

Increases in nitrogen (N) deposition and ultraviolet-B (UV-B) radiation play an important role in global climate change. Because coarse woody debris (CWD) represents a sizeable proportion of total carbon (C) pool in forest ecosystems, understanding the response of CWD decomposition to increased UV-B and N deposition become necessary for evaluating forest C storage under global climate change. In this study, we investigated the respiration of CWD (RCWD) in response to increased UV-B and N deposition over a two-year period for two tree species in subtropical Chinese forests: Cunninghamia lanceolata (Lamb.) Hook. (CL) and Cinnamomum camphora (L.) Presl (CC). We found that N and UV-B treatment, alone or in combination, significantly promoted RCWD, which was further magnified by increased temperature. Moreover, the combined treatment (UV-B + N) far exceeded the sum of the individual effects of N and UV-B treatments. Our results indicated that the three components of global climate change (increased UV-B, N deposition, and warming) worked interactively to accelerate CWD decomposition in forest ecosystems, suggesting that the biogeochemical cycling of subtropical forests could be altered greatly in the future, and this alteration must be considered in modelling the effects of global climate change.


Assuntos
Cinnamomum camphora , Cunninghamia , Nitrogênio/análise , Raios Ultravioleta , Madeira/análise , China , Madeira/efeitos dos fármacos , Madeira/efeitos da radiação
8.
Ann Work Expo Health ; 62(6): 674-688, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29878039

RESUMO

Sawmill workers are exposed to wood dust (a well-known carcinogen), microorganisms, endotoxins, resin acids (diterpenes), and vapours containing terpenes, which may cause skin irritation, allergy, and respiratory symptoms including asthma. The health effects of most of these exposures are poorly understood as most studies measure only wood dust. The present study assessed these exposures in the Norwegian sawmill industry, which processes predominantly spruce and pine. Personal exposures of wood dust, resin acids, endotoxin, fungal spores and fragments, mono-, and sesquiterpenes were measured in 10 departments in 11 saw and planer mills. The geometric mean (GM) and geometric standard deviation (GSD) thoracic exposures were: 0.09 mg m-3 dust (GSD 2.6), 3.0 endotoxin units (EU) m-3 (GSD 4.9), 0.4 × 105 fungal spores m-3 (GSD 4.2), 2 × 105 fungal fragments m-3 (GSD 3.2), and 1560 ng m-3 of resin acids (GSD 5.5). The GM (GSD) inhalable exposures were: 0.72 mg m-3 dust (2.6), 17 EU m-3 (4.3), 0.4 × 105 fungal spores m-3 (3.8), and 7508 ng m-3 (4.4) of resin acids. The overall correlation between the thoracic and inhalable exposure was strong for resin acid (rp = 0.84), but moderate for all other components (rp = 0.34-0.64). The GM (GSD) exposure to monoterpenes and sesquiterpenes were 1105 µg m-3 (7.8) and 40 µg m-3 (3.9), respectively. Although mean exposures were relatively low, the variance was large, with exposures regularly exceeding the recommended occupational exposure limits. The exposures to spores and endotoxins were relatively high in the dry timber departments, but exposures to microbial components and mono-and sesquiterpenes were generally highest in areas where green (undried) timber was handled. Dust and resin acid exposure were highest in the dry areas of the sawmills. Low to moderate correlation between components (rp ranging from 0.02 to 0.65) suggests that investigations of exposure-response associations for these components (both individually and combined) are feasible in future epidemiological studies.


Assuntos
Microbiologia do Ar , Poluentes Ocupacionais do Ar/análise , Poeira/análise , Exposição por Inalação/análise , Exposição Ocupacional/análise , Madeira/análise , Endotoxinas/análise , Fungos , Humanos , Indústrias , Noruega , Terpenos/análise
9.
Rev. biol. trop ; 66(2): 647-657, abr.-jun. 2018. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-977335

RESUMO

Abstract Mangroves represent an environment of great heterogeneity and low diversity of plant species that have structural and physiological adaptations linked to a high salinity environment. Laguncularia racemosa is a typical tree species in mangroves and transitional zones. This study aimed to compare the wood anatomy of L. racemosa (Combretaceae) in two different forests (mangroves and transitional forests), which have different soil conditions. For this, we obtained wood and soil samples in March 2016. We analyzed soil nutritional contents in one 15 cm deep soil sample per forest type. In addition, we selected five mangrove trees in each formation for wood anatomy analysis and took one wood sample per individual, per area. We prepared histological slides and separated materials following standard methods for wood anatomy studies. Soil analysis showed that mangrove soils had higher phosphorus, potassium and calcium contents. The transitional soil had lower pore water salinity and soil pH, probably due to high aluminum levels. Anatomical attributes differed between different forest populations. In the different wood aspects evaluated, we obtained higher values in mangrove individuals when compared to the transitional forest population: vessel elements length (375.79 mm), tangential vessels diameter (75.85 mm), frequency of vessels (11.90 mm) and fiber length (889.89 mm). Moreover, parenchyma rays height was larger in the samples of the transitional forest (392.80 mm), while the mangrove population presented wider rays (29.38 mm). The structure of the secondary xylem in the studied species apparently responds to edaphic parameters and shows variations that allow it to adjust to the environmental conditions. The population of the transitional forest showed a secondary xylem that invests more in protection than the mangrove population. Rev. Biol. Trop. 66(2): 647-657. Epub 2018 June 01.


Resumen Los manglares representan un ambiente de gran heterogeneidad y baja diversidad de especies vegetales que tienen adaptaciones estructurales y fisiológicas ligadas a un ambiente de alta salinidad. Laguncularia racemosa es una especie de árbol típico en los manglares y en zonas de transición. El objetivo de este estudio fue comparar la anatomía de la madera de L. racemosa (Combretaceae) en dos bosques distintos (manglares y bosques de transición) que tienen diferentes condiciones edáficas. Para esto se obtuvieron muestras de madera y suelo en marzo 2016. Se analizaron los contenidos nutricionales de una muestra de suelo de 15 cm de espesor por tipo de bosque. Además, se seleccionaron cinco árboles de mangle en cada formación para el análisis de la anatomía de la madera y se tomó una muestra de cada individuo por área. Se prepararon láminas histológicas y se separaron los materiales siguiendo métodos convencionales para estudios de anatomía de la madera. El análisis del suelo mostró que en el manglar hay mayor contenido de fósforo, potasio y calcio. El suelo del bosque de transición tiene menor salinidad del agua capilar y pH del suelo, probablemente debido a los altos niveles de aluminio. Los atributos anatómicos difirieron entre las distintas poblaciones de bosque. En los distintos aspectos de la madera evaluados, se obtuvieron valores más altos en los individuos del manglar comparados con los de la población del bosque de transición: longitud de los elementos de los vasos (375.79 mm), diámetro de los vasos tangenciales (75.85 mm), frecuencia de vasos (11.90 mm) y longitud de la fibra (889.89 mm). Además, la altura de los rayos de parénquima fue mayor en las muestras del bosque de transición (392.80 mm) mientras que la población de manglar presentó rayos más anchos (29.38 mm). La estructura del xilema secundario en la especie estudiada aparentemente responde a los parámetros edáficos y muestra variaciones que le permiten adecuarse a las condiciones ambientales. La población del bosque de transición mostró un xilema secundario que invierte más en protección que la población del manglar.


Assuntos
Árvores/anatomia & histologia , Madeira/análise , Estruturas Vegetais/anatomia & histologia , Áreas Alagadas , Brasil
10.
An. acad. bras. ciênc ; 90(1): 425-438, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886888

RESUMO

ABSTRACT This study evaluated the quality of heartwood and sapwood from mature trees of three species of Eucalyptus, by means of the qualification of their proportion, determination of basic and apparent density using non-destructive attenuation of gamma radiation technique and calculation of the density uniformity index. Six trees of each species (Eucalyptus grandis - 18 years old, Eucalyptus tereticornis - 35 years old and Corymbia citriodora - 28 years old) were used in the experimental program. The heartwood and sapwood were delimited by macroscopic analysis and the calculation of areas and percentage of heartwood and sapwood were performed using digital image. The uniformity index was calculated following methodology which numerically quantifies the dispersion of punctual density values of the wood around the mean density along the radius. The percentage of the heartwood was higher than the sapwood in all species studied. The density results showed no statistical difference between heartwood and sapwood. Differently from the density results, in all species studied there was statistical differences between uniformity indexes for heartwood and sapwood regions, making justifiable the inclusion of the density uniformity index as a quality parameter for Eucalyptus wood.


Assuntos
Madeira/anatomia & histologia , Eucalyptus/anatomia & histologia , Raios gama , Controle de Qualidade , Gravidade Específica , Madeira/análise , Brasil
11.
Environ Res ; 158: 431-435, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28689034

RESUMO

Over 3 billion people use solid fuels as a means of energy and heating source, and ~ 50% of households burn them in inefficient, poorly ventilated stoves. In 2010, ~ 43% of the 640 million preschool children in 220 countries suffered from a certain degree of anemia, with iron deficiency as the main cause in developed countries whereas its causes remained multifactorial in the undeveloped group. In this study, we explore the relations of country-wide variables that might affect the people's health status (from socioeconomic status to more specific variables such as water access). We found independent relationship between solid fuel use and anemia in children under five years old (p < 0.0001), taking into account the prevalence of anemia in pregnant woman and the access to improved water sources. Countries in which the population uses solid fuel the most have over three times higher anemia rates in children than countries with the lowest prevalence of solid fuels use. There is still a complex relationship between solid fuels use and anemia, as reflected in its worldwide significance (p < 0.05) controlled for measles immunization, tobacco consumption, anemia in pregnant mothers, girl's primary education, life expectancy and improved water access but not (p > 0.05) when weighing for sanitation access or income per capita.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Anemia/epidemiologia , Culinária , Calefação , Madeira/análise , Anemia/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Fatores de Risco , Fatores Socioeconômicos
12.
Environ Health Perspect ; 125(7): 077011, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28728136

RESUMO

BACKGROUND: Indoor burning of fuel for heating or cooking releases carcinogens. Little is known about the impact of indoor air pollution from wood-burning stoves or fireplaces on breast cancer risk. OBJECTIVES: In a large prospective cohort study, we evaluated the risk of breast cancer in relation to indoor heating and cooking practices. METHODS: Sister Study participants (n=50,884) were recruited from 2003­2009. Breast cancer­free women in the United States or Puerto Rico, 35­74 y old, with a sister with breast cancer were eligible. Participants completed questionnaires on indoor heating and cooking practices for both their enrollment and their longest adult residence. Cox regression was used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the association between indoor heating/cooking and breast cancer. RESULTS: A total of 2,416 breast cancer cases were diagnosed during follow-up (mean=6.4 y). Having an indoor wood-burning stove/fireplace in the longest adult residence was associated with a higher breast cancer risk [HR=1.11 (95% CI: 1.01, 1.22)]; the risk increased with average frequency of use [≥once/week, HR=1.17 (95% CI: 1.02, 1.34)] (p for trend=0.01). An elevated HR was seen for women burning wood [HR=1.09 (95% CI: 0.98, 1.21)] or natural gas/propane [HR=1.15 (95% CI: 1.00, 1.32)]. No association was observed for burning artificial fire-logs [HR=0.98 (95% CI: 0.85, 1.12)] except among women from western states [HR=1.36 (95% CI: 1.02, 1.81)]. CONCLUSIONS: In this prospective study, using an indoor wood-burning stove/fireplace in the longest adult residence at least once a week and burning either wood or natural gas/propane was associated with a modestly higher risk of breast cancer. https://doi.org/10.1289/EHP827.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Neoplasias da Mama/epidemiologia , Culinária/métodos , Calefação/métodos , Adulto , Idoso , Neoplasias da Mama/induzido quimicamente , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Gás Natural/análise , Estudos Prospectivos , Porto Rico/epidemiologia , Estados Unidos/epidemiologia , Madeira/análise
13.
Environ Pollut ; 220(Pt A): 150-158, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27650963

RESUMO

Microplastic particles are increasingly being discovered in diverse habitats and a host of species are found to ingest them. Since plastics are known to sorb hydrophobic organic contaminants (HOCs) there is a question of what risk of chemical exposure is posed to aquatic biota from microplastic-associated contaminants. We investigate bioavailability of polychlorinated biphenyls (PCBs) from polypropylene microplastic by measuring solid-water distribution coefficients, gut fluid solubilization, and bioaccumulation using sediment invertebrate worms as a test system. Microplastic-associated PCBs are placed in a differential bioavailability framework by comparing the results to several other natural and anthrogenic particles, including wood, coal, and biochar. PCB distribution coefficients for polypropylene were higher than natural organic materials like wood, but in the range of lipids and sediment organic carbon, and smaller than black carbons like coal and biochars. Gut fluid solubilization potential increased in the order: coal < polypropylene < biochar < wood. Interestingly, lower gut fluid solubilization for polypropylene than biochar infers that gut fluid micelles may have solubilized part of the biochar matrix while bioaccessibility from plastic can be limited by the solubilizing potential of gut fluids dependent on the solid to liquid ratio or renewal of fluids in the gut. Biouptake in worms was lower by 76% when PCBs were associated with polypropylene compared to sediment. The presence of microplastics in sediments had an overall impact of reducing bioavailability and transfer of HOCs to sediment-ingesting organisms. Since the vast majority of sediment and suspended particles in the environment are natural organic and inorganic materials, pollutant transfer through particle ingestion will be dominated by these particles and not microplastics. Therefore, these results support the conclusion that in most cases the transfer of organic pollutants to aquatic organisms from microplastic in the diet is likely a small contribution compared to other natural pathways of exposure.


Assuntos
Disponibilidade Biológica , Carvão Vegetal/análise , Carvão Mineral/análise , Oligoquetos/metabolismo , Plásticos/análise , Bifenilos Policlorados/análise , Polipropilenos/análise , Madeira/análise , Animais , Sedimentos Geológicos/química , Plásticos/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/análise , Madeira/química
14.
J Toxicol Environ Health A ; 79(22-23): 1070-1077, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27924719

RESUMO

Obeche wood is a prominent cause of allergic occupational asthma. To reduce the risk of immunoglobulin E (IgE)-mediated sensitization it is important to assess airborne obeche wood allergen concentrations at exposed workplaces. Therefore, a highly sensitive obeche wood allergen immunoassay was developed and applicability was proven on airborne passive dust samples in Spanish wood workshops. Obeche wood sandwich enzyme-linked immunosorbent assay (ELISA) polyclonal antibodies (pAbs) were developed. Test specificity was verified by different wood and mold extracts. Obeche wood allergen monitoring was conducted in four Spanish wood workshops, including wood-dust-exposed and nonexposed areas inside and outside the workplaces, as well as controls. Dust was collected with electrostatic dust collectors (EDC). Measuring range of the obeche wood sandwich-ELISA was between 36 pg/ml and 1.6 µg/ml. The test system showed only marginal reactivity to other hardwoods and no reactivity to softwoods and molds. Obeche allergen was detected in all EDC from workplaces. The highest concentration was measured in the workshop with the longest obeche wood exposure (geometric mean [GM]: 7548 µg/m2); shorter obeche wood processing periods resulted in lower amounts of allergen (GM: 29 µg/m2). Obeche wood allergen transfer from exposed workplaces to nonexposed areas inside and outside the workshop was assessed. In control EDC from nonexposed facilities/homes no obeche wood allergen was found. The new obeche wood sandwich-ELISA is a valid tool to quantify obeche allergen exposure. Evidence indicates it will be possible to monitor obeche allergen exposure during different processes, as well as transfer effects in nonexposed areas.


Assuntos
Alérgenos/análise , Poeira/análise , Ensaio de Imunoadsorção Enzimática/métodos , Malvaceae/química , Exposição Ocupacional , Madeira/análise , Monitoramento Ambiental/instrumentação , Humanos , Espanha
15.
Chemosphere ; 163: 313-321, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27544654

RESUMO

Wood combustion has been shown to contribute significantly to emissions of polycyclic aromatic hydrocarbons and hydroxylated polycyclic aromatic hydrocarbons, compounds with toxic and carcinogenic properties. However, only a small number of hydroxylated polycyclic aromatic hydrocarbons have been determined in particles from wood combustion, usually compounds with available reference standards. In this present study, suspect and non-target screening strategies were applied to characterize the wood smoke particles from four different wood types and two combustion conditions with respect to hydroxylated polycyclic aromatic hydrocarbons and other organic compounds. In the suspect screening, 32 peaks corresponding to 12 monohydroxylated masses were tentatively identified by elemental composition assignments and matching of isotopic pattern and fragments. More than one structure was suggested for most of the measured masses. Statistical analysis was performed on the non-target screening data in order to single out significant peaks having intensities that depend on the wood type and/or combustion condition. Significant peaks were found in both negative and positive ionization modes, with unique peaks for each wood type and combustion condition, as well as a combination of both factors. Furthermore, structural elucidation of some peaks was done by comparing the spectra in the samples with spectra found in the spectral databases. Six compounds were tentatively identified in positive ionization mode, and 19 in negative ionization mode. The results in this present study demonstrate that there are significant overall differences in the chemistry of wood smoke particles that depends on both the wood type and the combustion condition used.


Assuntos
Compostos Orgânicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Fumaça/análise , Madeira/análise , Poluentes Atmosféricos/análise , Calibragem , Cromatografia Líquida , Monitoramento Ambiental/métodos , Espectrometria de Massas , Análise de Componente Principal , Análise de Regressão , Espectrometria de Massas por Ionização por Electrospray , Temperatura
16.
Artigo em Inglês | MEDLINE | ID: mdl-27409416

RESUMO

The pollution of particulate matter (PM) is of great concern in China and many other developing countries. It is generally recognized that the toxicity of PM is source and property dependent. However, the relationship between PM properties and toxicity is still not well understood. In this study, PM samples from direct emissions of wood, straw, coal, diesel combustion, cigarette smoking and ambient air were collected and characterized for their physicochemical properties. Their expression of intracellular reactive oxygen species (ROS) and levels of inflammatory cytokines (i.e., tumor necrosis factor-α (TNF-α)) was measured using a RAW264.7 cell model. Our results demonstrated that the properties of the samples from different origins exhibited remarkable differences. Significant increases in ROS were observed when the cells were exposed to PMs from biomass origins, including wood, straw and cigarettes, while increases in TNF-α were found for all the samples, particularly those from ambient air. The most important factor associated with ROS generation was the presence of water-soluble organic carbon, which was extremely abundant in the samples that directly resulted from biomass combustion. Metals, endotoxins and PM size were the most important properties associated with increases in TNF-α expression levels. The association of the origins of PM particles and physicochemical properties with cytotoxic properties is illustrated using a cluster analysis.


Assuntos
Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental/métodos , Material Particulado/química , Material Particulado/toxicidade , Poluentes Atmosféricos/análise , China , Carvão Mineral/análise , Gasolina/análise , Gasolina/toxicidade , Metais/análise , Metais/química , Material Particulado/análise , Fumaça/análise , Poluição por Fumaça de Tabaco/efeitos adversos , Madeira/análise , Madeira/química
17.
Waste Manag ; 49: 560-570, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26724232

RESUMO

To identify a route for organic wastes utilisation, biochar made from various feedstocks (landfill pine saw dust, sewage sludge, and poultry litter) and at diverse pyrolysis conditions, were collected. These biochars were used to fabricate wood and polypropylene biocomposites with a loading level of 24 mass%. The composites were tested for their mechanical, chemical, thermal, morphological, and fire properties. The poultry litter biochar biocomposite, with highest ash content, was found to have high values of tensile/flexural strength, tensile/flexural modulus, and impact strength, compared to other composites. In general, addition of all the biochars enhanced the tensile/flexural moduli of the composites. The crystal structure of polypropylene in the composite was intact after the incorporation of all the biochars. The final chemical and crystal structure of the composite were an additive function of the individual components. The biochar particles along with wood acted as nucleating agents for the recrystallization of polypropylene in composite. Each component in the composites was found to decompose individually under thermal regime. The electron microscopy revealed the infiltration of polypropylene into the biochar pores and a general good dispersion in most composites. The poultry litter composite was found to have lower heat release rate under combustion regime.


Assuntos
Carvão Vegetal/análise , Esterco/análise , Esgotos/análise , Gerenciamento de Resíduos/métodos , Madeira/análise , Animais , Incineração , Pinus , Aves Domésticas
18.
Braz. j. biol ; 75(4): 940-947, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768214

RESUMO

Abstract Lignocellulose is the most abundant environmental component and a renewable organic resource in soil. There are some filamentous fungi which developed the ability to break down and use cellulose, hemicellulose and lignin as an energy source. The objective of this research was to analyze the effect of three nitrogen resources (ammonium sulfate, saltpetre, soybean) in the holocellulolitic activity of Lentinula edodes EF 50 using as substrate sawdust E. benthamii. An experimental design mixture was applied with repetition in the central point consisting of seven treatments (T) of equal concentrations of nitrogen in ammonium sulfate, potassium nitrate and soybean. The enzymatic activity of avicelase, carboxymetilcellulase, β-glucosidase, xylanases and manganese peroxidase was determined. The humidity, pH, water activity (aw) and qualitative analysis of mycelial growth in 8 times of cultivation were evaluated. The results showed negative effect on enzyme production in treatments with maximum concentration of ammonium sulfate and potassium nitrate. The treatments with cooked soybean flour expressed higher enzymatic activities in times of 3, 6 and 9 days of culture, except in the activity of manganese peroxidase. The highest production was observed in the treatment with ammonium sulfate, and soybean (83.86 UI.L–1) at 20 days of cultivation.


Resumo Lignocelulose é o componente mais abundante do meio ambiente e recurso orgânico renovável no solo. Alguns fungos filamentosos têm desenvolvido a habilidade de degradar e utilizar celulose, hemicelulose e lignina como fonte de energia. O objetivo deste trabalho foi analisar o efeito de três fontes de nitrogênio (sulfato de amônio, nitrato de potássio e farelo de soja) na atividade enzimática de Lentinula edodes EF 50 utilizando como substrato serragem de E. benthamii. Foi aplicado um planejamento experimental de mistura com três repetições no ponto central constituído de sete tratamentos (T) de iguais concentrações em nitrogênio de sulfato de amônia, nitrato de potássio e farinha de soja cozida. Foram determinadas a atividade enzimática da avicelase, carboximetilcelulase, β-glicosidase, xilanases e manganês peroxidase. Foram avaliados o teor de umidade, pH, atividade de água (aw) e análise qualitativa do crescimento micelial em 8 tempos de cultivo. Os resultados mostraram efeito negativo na produção das enzimas nos tratamentos com máxima concentração de sulfato de amônia e nitrato de potássio. Os tratamentos com farinha de soja cozida expressaram maiores atividades enzimáticas, nos tempos de 3, 6 e 9 dias de cultivo exceto na atividade do manganês peroxidase. A maior produção foi observada no tratamento com sulfato de amônia e farinha de soja cozida (83.86 UI.L–1) em 20 dias de cultivo.


Assuntos
Biomassa , Lignina/farmacologia , Nitrogênio/metabolismo , Cogumelos Shiitake/enzimologia , Cogumelos Shiitake/crescimento & desenvolvimento , Sulfato de Amônio/metabolismo , Eucalyptus/química , Nitratos/metabolismo , Compostos de Potássio/metabolismo , Glycine max/química , Madeira/análise
19.
Asian Pac J Cancer Prev ; 16(10): 4339-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26028096

RESUMO

Occupational exposure to wood dust is one cause of nasopharyngeal cancer (NPC); however, assessing this exposure remains problematic. Therefore, the objective of this study was to develop a semi-quantitative exposure assessment method and then utilize it to evaluate the association between occupational exposure to wood dust and the development of NPC. In addition, variations in risk by histology were examined. A case-control study was conducted with 327 newly diagnosed cases of NPC at the National Cancer Institute and regional cancer centers in Thailand with 1:1 controls matched for age, gender and geographical residence. Occupational information was obtained through personal interviews. The potential probability, frequency and intensity of exposure to wood dust were assessed on a job-by-job basis by experienced experts. Analysis was performed by conditional logistic regression and presented in odds ratio (ORs) estimates and 95% confidence intervals (CI). Overall, a non significant relationship between occupational wood dust exposure and NPC risk for all subjects was observed (ORs=1.61, 95%CI 0.99-2.59); however, the risk became significant when analyses focused on types 2 and 3 of NPC (ORs=1.62, 95%CI 1.03-2.74). The significant association was stronger for those exposed to wood dust for >10 year (ORs=2.26, 95%CI 1.10-4.63), for those with first-time exposure at age>25 year (ORs=2.07, 95%CI 1.08-3.94), and for those who had a high cumulative exposure (ORs=2.17, 95%CI 1.03-4.58) when compared with those considered unexposed. In conclusion, wood dust is likely to be associated with an increased risk of type 2 or 3 NPC in the Thai population. The results of this study show that semi-quantitative exposure assessment is suitable for occupational exposure assessment in a case control study and complements the information from self-reporting.


Assuntos
Poeira , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/patologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/patologia , Exposição Ocupacional/efeitos adversos , Madeira/toxicidade , Adulto , Estudos de Casos e Controles , Poeira/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/etiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/análise , Fatores de Risco , Tailândia/epidemiologia , Madeira/análise
20.
Waste Manag Res ; 33(4): 332-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25784689

RESUMO

Rose oil is a specific essential oil that is produced mainly for the cosmetics industry in a few selected locations around the world. Rose oil production is a water distillation process from petals of Rosa damascena Mill. Since the oil content of the rose petals of this variety is between 0.3-0.4% (w/w), almost 4000 to 3000 kg of rose petals are needed to produce 1 kg of rose oil. Rose oil production is a seasonal activity and takes place during the relatively short period where the roses are blooming. As a result, large quantities of solid waste are produced over a limited time interval. This research aims: (i) to determine the possibilities of aerobic co-composting as a waste management option for rose oil processing waste with caged layer manure; (ii) to identify effects of different carbon sources - straw or sawdust on co-composting of rose oil processing waste and caged layer manure, which are both readily available in Isparta, where significant rose oil production also takes place; (iii) to determine the effects of different C/N ratios on co-composting by the means of organic matter decomposition and dry matter loss. Composting experiments were carried out by 12 identical laboratory-scale composting reactors (60 L) simultaneously. The results of the study showed that the best results were obtained with a mixture consisting of 50% rose oil processing waste, 64% caged layer manure and 15% straw wet weight in terms of organic matter loss (66%) and dry matter loss (38%).


Assuntos
Resíduos Industriais/análise , Óleos Voláteis/química , Rosa/química , Gerenciamento de Resíduos/métodos , Aerobiose , Carbono/metabolismo , Hordeum , Esterco/análise , Nitrogênio/metabolismo , Pinus , Madeira/análise
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