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51.

We report a small hawk-like diurnal bird from the early Oligocene (30–31 million years ago) of Poland. Aviraptor longicrus, n. gen. et sp. is of a size comparable with the smallest extant Accipitridae. The new species is characterized by very long legs, which, together with the small size, suggest an avivorous (bird-eating) feeding behavior. Overall, the new species resembles extant sparrowhawks (Accipiter spp.) in the length proportions of the major limb bones, even though some features indicate that it convergently acquired an Accipiter-like morphology. Most specialized avivores amongst extant accipitrids belong to the taxon Accipiter and predominantly predate small forest passerines; the smallest Accipiter species also hunts hummingbirds. Occurrence of a possibly avivorous raptor in the early Oligocene of Europe is particularly notable because A. longicrus coexisted with the earliest Northern Hemispheric passerines and modern-type hummingbirds. We therefore hypothesize that the diversification of these birds towards the early Oligocene may have triggered the evolution of small-sized avivorous raptors, and the new fossil may exemplify one of the earliest examples of avian predator/prey coevolution.

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Public participation within environmental monitoring may contribute to increasing the knowledge on the state of the environment at the same time it promotes citizens' involvement in environmental protection. However, the use of voluntary collected data is limited due to a lack of confidence in data collection procedures. Additionally, data quality is often unknown and the data are usually dispersed and non-structured. Information and communication technologies (ICT) may promote the use of voluntary collected data through the development of a collaborative system that incorporates tools and methodologies to facilitate data collection, access and validation. Furthermore, the use of ICT may promote public involvement within environmental monitoring, since it facilitates communication among all the stakeholders. This paper analyses the role of ICT in developing a system for environmental collaborative monitoring intending to promote the use of volunteer collected data. It starts by analysing the role of volunteers within environmental monitoring and continues analysing the potential of ICT to take advantage of the benefits of using data collected by citizens. A collaborative system that allows the public to express its knowledge on the state of the environment is described. Special emphasis is given to tools that explore non-traditional types of environmental data such as images, sounds and videos in association with spatial information. To illustrate the above mentioned concepts, a case study for beach quality monitoring developed within the Senses@Watch project, is described.  相似文献   
54.
The extensive use of pesticides represents a risk to human health and to the environment. This study aimed to investigate if the exposure to atrazine and diuron, two herbicides widely used in Brazil, could induce changes in the susceptibility profile to aztreonam, colistin and polymyxin B antimicrobials in isolates of P. aeruginosa obtained from soil samples by using the determination of minimum inhibitory concentration (MIC) test. Three isolates had an increase of MIC to aztreonam after exposure to both herbicides and one isolate did not show any MIC change. The MexAB-OprM efflux pump has already been upregulated in these isolates and the herbicides atrazine and diuron did not increase MexAB-OprM overexpression. Therefore, the decrease in aztreonam susceptibility was not directly related to this pump, suggesting that probably other mechanisms should be involved.  相似文献   
55.
In semi-arid areas like the Kairouan region, salinization has become an increasing concern because of the constant irrigation with saline water and over use of groundwater resources, soils, and aquifers. In this study, a methodology has been developed to evaluate groundwater contamination risk based on the unsaturated zone hydraulic properties. Two soil profiles with different ranges of salinity, one located in the north of the plain and another one in the south of plain (each 30 m deep) and both characterized by direct recharge of the aquifer, were chosen. Simulations were conducted with Hydrus-1D code using measured precipitation data for the period 1998–2003 and calculated evapotranspiration for both chosen profiles. Four combinations of initial conditions of water content and salt concentration were used for the simulation process in order to find the best match between simulated and measured values. The success of the calibration of Hydrus-1D allowed the investigation of some scenarios in order to assess the contamination risk under different natural conditions. The aquifer risk contamination is related to the natural conditions where it increased while facing climate change and temperature increase and decreased in the presence of a clay layer. Hydrus-1D was a useful tool to predict the groundwater level and quality in the case of a direct recharge and in the absence of any information related to the soil layers except for the texture.  相似文献   
56.
The tanning industry is one of the largest environmental polluters due to high generation waste in all production processes, but the tanning is particularly worrisome due to the use of significant amounts of chromium. Cr is an element potentially toxic to both health and the environment, depending on the concentration and the oxidation state. Cr(VI) can come in contact with human skin when using leather goods, which can cause allergies and dermatitis, besides being carcinogenic. Considering that approximately 90% of the world production of leather is performed with Cr salts, the determination of this element in leather is necessary to avoid exposure to the risks that the element can provide. The main goal of this study was the development of an alternative analytical method for the determination of Cr in leathers (ovine and bovine leather tanned with Cr and vegetable tannin) using wavelength dispersive X-ray fluorescence (WDXRF) for direct solid analysis. Besides performing analysis of the chemical composition and determination of Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Ni, Pb, Sb, Sr, Ti, and Zn in leather by inductively coupled plasma optical emission spectrometry (ICP OES). Principal component analysis (PCA) was also used in the evaluation of the WDXRF and ICP OES data sets. WDXRF calibration models for Cr presented satisfactory figures of merit and the analysis of the leathers revealed an alarming concentration of total Cr in the samples reaching 21,353 mg kg?1.  相似文献   
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The present study sought to objectively demonstrate how a researcher can, in a structured way, select relevant articles about alternative heterogeneous catalysts in photocatalytic processes. Therefore, the ProKnow-C (Knowledge Development Process – Constructivist) method was used to systematize the results found, with the application bibliometric and systematic analysis techniques for the evaluation of the results. The search string adopted as criteria was: solar photocatalysis AND heterogeneous catalysts OR alternative catalysts AND effluents. The databases were Web of Science, Science Direct and Scopus. The final bibliographic portfolio obtained for the research theme was made up of 19 articles. It was possible to verify advances in the number of publications on the theme over the evaluated period, with the Journal of Photochemistry and Photobiology A: Chemistry standing out in the final portfolio. Evaluating each article in the portfolio individually, it was possible to verify that most studies use combinations of catalysts already reported to create an alternative material to those already investigated in the literature. Those that use waste as catalysts chose to source this material from treatment plants and the steel industry. Around 58% of the papers used hydrogen peroxide in their processes, while 42% chose not to use it. Finally, approximately 63% of the papers in the portfolio used synthetic effluent in their processes, while the rest (37% of the research) chose to use real effluent. The results obtained in this research by applying the method can contribute to studies related to heterogeneous photocatalysis by alternative means over the years.  相似文献   
59.
Journal of Material Cycles and Waste Management - Waste water contaminated with inorganic mercury is considered a serious environmental problem, mainly due to the hazardous effects this contaminant...  相似文献   
60.
Coconut, sisal and jute fibers were added as reinforcement materials in a biodegradable polymer matrix comprised of starch/gluten/glycerol. The content of fibers used in the composites varied from 5% to 30% by weight of the total polymers (starch and gluten). Materials were processed in a Haake torque rheometer (120 °C, 50 rpm) for 6 min. The mixtures obtained were molded by heat compression and further characterized. Addition of lignocellulosic fibers in the matrix decreased the water absorption at equilibrium. The diffusion coefficient decreased sharply around 5% fiber concentration, and further fiber additions caused only small variations. The thermogravimetric (TG) analysis revealed improved thermal stability of matrix upon addition of fibers. The Young’s modulus and ultimate tensile strength increased with fiber content in the matrix. The storage modulus increased with increasing fiber content, whereas tanδ curves decreased, confirming the reinforcing effect of the fibers. Morphology of the composites analyzed under the scanning electron microscope (SEM) exhibited good interfacial adhesion between the matrix and the added fibers. Matrix degraded rapidly in compost, and addition of increased amounts of coconut fiber in the matrix caused a slowdown the biodegradability of the matrix. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may be suitable.  相似文献   
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