133 research outputs found

    No evidence of suitability of prophylactic fluids for wildfire prevention at landscape scales

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    Yu et al. propose a viscoelastic fluid as a prophylactic fire-retardant treatment in landscapes at high risk of wildfires. We argue that, while the idea is worth exploring further, their data do not support its suitability for real landscape-scale applications.Peer reviewe

    Identificación de adulteraciones en café tostado mediante cromatografía de gases acoplada a espectrometría de masas

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    Globally, coffee is the second most commercialized product after crude oil. Nevertheless, due to its high price, this product is usually adulterated with lower-cost products. The objective of the present study was to develop a method based on the combination of solid phase microextraction (SPME) with gas chromatography coupled to mass spectrometry (GC-MS) and principal component analysis (PCA), to detect the presence of faba beans and/or barley in roasted coffee. In addition, the SPME of volatile coffee compounds was optimized using the response surface methodology. The optimized SPME conditions were 16 min as conditioning time and 35 min as extraction time. Besides, 44, 36 and 24 compounds were identified, in coffee, barley and bean, respectively. Finally, the developed method allowed detecting the probable presence of faba bean in four commercial coffee samples. To our knowledge, this is the first time that volatile compounds have been described in roasted faba bean. In addition, the presence of barley in these samples was ruled out.En el mundo, el café es el segundo producto más comercializado después del petróleo. Sin embargo, debido a su elevado precio, suele ser adulterado con materiales de menor costo. El objetivo de la presente investigación fue desarrollar un método basado en la combinación de las técnicas de microextracción de fase sólida (SPME) con la cromatografía de gases acoplado a espectrometría de masas (GC-MS) y el análisis de componentes principales (PCA), para detectar la presencia de haba y/o cebada en café tostado. Además, se optimizó la SPME de compuestos volátiles del café, mediante la metodología de superficie de respuesta. Respecto al método de extracción, se encontró que las condiciones óptimas fueron 16 y 35 min, para el tiempo de equilibrio y extracción, respectivamente. Por otra parte, se identificaron 44, 36 y 24 compuestos, en café, cebada y haba, respectivamente. De acuerdo con nuestro conocimiento, es el primer estudio respecto a la identificación de compuestos volátiles en haba tostada. Finalmente, el método desarrollado permitió detectar la probable presencia de haba en cuatro muestras comerciales de café. Además, se descartó la presencia de cebada en estas muestras

    Fire effects on soils: the human dimension

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    Soils are among the most valuable non-renewable resources on the Earth. They support natural vegetation and human agro-ecosystems, represent the largest terrestrial organic carbon stock, and act as stores and filters for water. Mankind has impacted on soils from its early days in many different ways, with burning being the first human perturbation at landscape scales. Fire has long been used as a tool to fertilize soils and control plant growth, but it can also substantially change vegetation, enhance soil erosion and even cause desertification of previously productive areas. Indeed fire is now regarded by some as the seventh soil-forming factor. Here we explore the effects of fire on soils as influenced by human interference. Human-induced fires have shaped our landscape for thousands of years and they are currently the most common fires in many parts of the world. We first give an overview of fire effect on soils and then focus specifically on (i) how traditional land-use practices involving fire, such as slash-and-burn or vegetation clearing, have affected and still are affecting soils; (ii) the effects of more modern uses of fire, such as fuel reduction or ecological burns, on soils; and (iii) the ongoing and potential future effects on soils of the complex interactions between human-induced land cover changes, climate warming and fire dynamics. This article is part of the themed issue ‘The interaction of fire and mankind’

    Weed control options in conventional and GM maize

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    En el proyecto AMIGA, que estudia los posibles efectos de los cultivos modificados genéticamente y su manejo sobre el agro-eco-sistema y la biodiversidad, se han evaluado varios tratamientos herbicidas sobre maíz Bt y maíz convencional. Se estableció un ensayo de seis hectáreas durante dos años en el que se han utilizado cinco manejos con herbicida que incluyen tratamiento convencional, reducido, glifosato y dos combinaciones de los anteriores. Se muestreó a lo largo del desarrollo del cultivo para determinar las especies de malas hierbas y artrópodos en el tiempo así como su abundancia y diversidad mediante examen visual y uso de trampas de gravedad y adhesivas amarillas. En este trabajo se presentan datos de abundancia de malas hierbas a madurez fisiológica del cultivo y del total de artrópodos en muestreo visual.Effect on weeds and arthropods In the context of AMIGA project which studies the posible effects of genetically modified crops and their management on the agro-ecosystem and biodiversity, we have studied various herbicide treatments applied on conventional and Bt A field was conducted for two years in a six ha plot. Five herbicide treatments including conventional, reduced, glyphosate and two herbicides combinations were established. We sampled along the cropping period to determine the species of weeds and arthropods over time and their abundance and diversity. The presence of arthropods was determined by visual examination and the use of pitfall and yellow sticky traps. In this work whole abundance of weeds at physiological maturity of the crop and total abundance of arthropod in visual examination are presented

    Molecular characterisation of protist parasites in human-habituated mountain gorillas (Gorilla beringei beringei), humans and livestock, from Bwindi impenetrable National Park, Uganda

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    Over 60 % of human emerging infectious diseases are zoonotic, and there is growing evidence of the zooanthroponotic transmission of diseases from humans to livestock and wildlife species, with major implications for public health, economics, and conservation. Zooanthroponoses are of relevance to critically endangered species; amongst these is the mountain gorilla (Gorilla beringei beringei) of Uganda. Here, we assess the occurrence of Cryptosporidium, Cyclospora, Giardia, and Entamoeba infecting mountain gorillas in the Bwindi Impenetrable National Park (BINP), Uganda, using molecular methods. We also assess the occurrence of these parasites in humans and livestock species living in overlapping/adjacent geographical regions

    Incidence and molecular typing of Mycobacterium kansasii in a defined geographical area in Catalonia, Spain

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    A retrospective population-based study was conducted between January 1990 and December 1998 to investigate the incidence of Mycobacterium kansasii disease and the heterogeneity of the isolates in a well-defined geographical area in Catalonia, Spain. A total of 136 patients were identified. Overall incidence and incidence in AIDS patients was 1. 5 (95% CI 1.2-1.8) and 1089.6 (95% CI 689-1330) cases/100 000 persons per year respectively, which is comparable to that reported from most of other geographical areas. Surprisingly, although 7 subtypes of M. kansasii have been consistently reported, in the present study 91 of the 93 isolates (97.8%) tested for genotype were subtype I, regardless of HIV status of the patients. In conclusion, the high rate of infection observed in the AIDS population contributes significantly to the burden of the M. kansasii disease in our area. M. kansasii disease in our geographical area was almost exclusively caused by subtype I regardless of HIV status

    Carbon sequestration potential and physicochemical properties differ between wildfire charcoals and slow-pyrolysis biochars

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    Pyrogenic carbon (PyC), produced naturally (wildfire charcoal) and anthropogenically (biochar), is extensively studied due to its importance in several disciplines, including global climate dynamics, agronomy and paleosciences. Charcoal and biochar are commonly used as analogues for each other to infer respective carbon sequestration potentials, production conditions, and environmental roles and fates. The direct comparability of corresponding natural and anthropogenic PyC, however, has never been tested. Here we compared key physicochemical properties (elemental composition, δ13C and PAHs signatures, chemical recalcitrance, density and porosity) and carbon sequestration potentials of PyC materials formed from two identical feedstocks (pine forest floor and wood) under wildfire charring- and slow-pyrolysis conditions. Wildfire charcoals were formed under higher maximum temperatures and oxygen availabilities, but much shorter heating durations than slow-pyrolysis biochars, resulting in differing physicochemical properties. These differences are particularly relevant regarding their respective roles as carbon sinks, as even the wildfire charcoals formed at the highest temperatures had lower carbon sequestration potentials than most slow-pyrolysis biochars. Our results challenge the common notion that natural charcoal and biochar are well suited as proxies for each other, and suggest that biochar’s environmental residence time may be underestimated when based on natural charcoal as a proxy, and vice versa

    Fuzzy approach for risk assessment of brominated flame retardants in aquatic ecosystems

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    Brominated flame retardants (BFR) are pollutants that represent a threat to both human health and environment due to their industrial use, their persistence and their ability to bioaccumulate and biomagnify in food chains, especially in the aquatic one. For the last ten years contamination levels for this type of compounds have been reported for European, North American and Asian human tissue, sediments and biota samples [1-3]. However, monitoring efforts into the assessment of BFRs contamination levels in Latin America are scarce. In this study, a model for the evaluation of the environmental risk of BFRs in the aquatic ecosystems has been developed. It has been based on a technical application of the Fuzzy Theory [4]. In particular, three interconnected Fuzzy Inference Systems (FIS) have been created through the use of the Fuzzy Toolbox in Matlab. In order to improve and make the model scientifically robust, several international experts have been questioned about different information required to build the fuzzy system. Information from 38 questionnaires have been collected and statistically treated.Preprin

    Molecular Detection and Characterization of Blastocystis sp. and Enterocytozoon bieneusi in Cattle in Northern Spain

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    Some enteric parasites causing zoonotic diseases in livestock have been poorly studied or even neglected. This is the case in stramenopile Blastocystis sp. and the microsporidia Enterocytozoon bieneusi in Spain. This transversal molecular epidemiological survey aims to estimate the prevalence and molecular diversity of Blastocystis sp. and E. bieneusi in cattle faecal samples (n = 336) in the province of Álava, Northern Spain. Initial detection of Blastocystis and E. bieneusi was carried out by polymerase chain reaction (PCR) and Sanger sequencing of the small subunit (ssu) rRNA gene and internal transcribed spacer (ITS) region, respectively. Intra-host Blastocystis subtype diversity was further investigated by next generation amplicon sequencing (NGS) of the ssu rRNA gene in those samples that tested positive by conventional PCR. Amplicons compatible with Blastocystis sp. and E. bieneusi were observed in 32.1% (108/336, 95% CI: 27.2-37.4%) and 0.6% (2/336, 95% CI: 0.0-1.4%) of the cattle faecal samples examined, respectively. Sanger sequencing produced ambiguous/unreadable sequence data for most of the Blastocystis isolates sequenced. NGS allowed the identification of 10 Blastocystis subtypes including ST1, ST3, ST5, ST10, ST14, ST21, ST23, ST24, ST25, and ST26. All Blastocystis-positive isolates involved mixed infections of 2-8 STs in a total of 31 different combinations. The two E. bieneusi sequences were confirmed as potentially zoonotic genotype BEB4. Our data demonstrate that Blastocystis mixed subtype infections are extremely frequent in cattle in the study area. NGS was particularly suited to discern underrepresented subtypes or mixed subtype infections that were undetectable or unreadable by Sanger sequencing. The presence of zoonotic Blastocystis ST1, ST3, and ST5, and E. bieneusi BEB4 suggest cross-species transmission and a potential risk of human infection/colonization.This research was funded by the Health Institute Carlos III (ISCIII), Ministry of Science, Innovation and Universities (Spain), grant numbers PI16CIII/00024 and USDA-ARS Project No: 8042–32000-112–00-D.S
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