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51.

In rural areas, depopulation is mainly due to a lack of economic and employment opportunities. In this context, the reservoirs already built can be a source of socioeconomic development based on tourism and outdoor leisure activities. The condition for this development to materialize is that reservoir management considers these activities. In Central Spain, a process of rural depopulation has been generated in the municipalities around the reservoirs at the Upper Tagus River, as water management allows water transfers from the Tagus to the Segura River without taking into account regulations that prioritize and protect donor basin users. Through the comparison of reservoir water management and demographic data of two rural areas close to the reservoirs, this article reveals the direct relationship between reservoir management that enables recreational uses with its consequent socioeconomic development and the maintenance of the population in the territory. Consequently, reservoir water management based on the socioeconomic development of reservoir banks is necessary and a priority over transfers to another basin.

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52.
Chemical composition and fatty acid profiles were determined in Caiman yacare meat originating from the neck and tail cuts of animals raised in the wild (n = 6) or in captivity (n = 6), slaughtered at a live weight of approximately 6 kg. All experimental methods were approved by the appropriate environmental protection agencies. Most chemical components were affected by the origin-cut interaction, with the tail cut of wild animals having the highest amount of intramuscular fat (19.2% of DM) and the lowest of moisture (71.8%) and protein (77.0% of DM). Yacare meat had low amounts of SFA (35.1%), which were similar (P > 0.05) in the cuts and origins studied. The total amount of PUFA was higher (P < 0.05) in wild (31.0%) than in captive animals (23.6%), and n − 3 fatty acids had means of about 5% and 2% for the same groups, respectively (P < 0.05). In general, the FA profile of intramuscular fat in yacare meat had a desirable PUFA/SFA ratio above 0.4.  相似文献   
53.
This paper reports on the steam reforming, in continuous regime, of the aqueous fraction of bio-oil obtained by flash pyrolysis of lignocellulosic biomass (sawdust). The reaction system is provided with two steps in series: i) thermal step at 200 °C, for the pyrolytic lignin retention, and ii) reforming in-line of the treated bio-oil in a fluidized bed reactor, in the range 600–800 °C, with space-time between 0.10 and 0.45 gcatalyst h (gbio-oil)−1. The benefits of incorporating La2O3 to the Ni/α-Al2O3 catalyst on the kinetic behavior (bio-oil conversion, yield and selectivity of hydrogen) and deactivation were determined. The significant role of temperature in gasifying coke precursors was also analyzed. Complete conversion of bio-oil is achieved with the Ni/La2O3-αAl2O3 catalyst, at 700 °C and space-time of 0.22 gcatalyst h (gbio-oil)−1. The catalyst deactivation is low and the hydrogen yield and selectivity achieved are 96% and 70%, respectively.  相似文献   
54.
Anisakids are a group of widely distributed nematodes which have acquired high social relevance due to their involvement in foodborne infections caused by consumption of raw or undercooked seafood. A TaqMan®-LNA probe real-time assay targeting the cytochrome oxidase subunit I (COI) was developed allowing the simultaneous detection of the most important anisakids species present in fish and seafood products.The determination of the detection limit in terms of ppm was 1 ppmFor the validation of method developed, twenty fish and cephalopod samples were experimentally contaminated with anisakid. It was checked that in cases in any anisakids species was present, it was detected because the Ct was always less than 35 and did not produce any case false negatives. The main novelty of this work lies in the fact that it can be applied to all kinds of processed products, including those undergoing intensive processes of transformation, as for instance canned foods. The proposed methodology is rapid, robust, highly sensitive and readily adaptable in routine molecular diagnostic laboratories, and can be employed as molecular screening method in order to assess the food security.  相似文献   
55.
The present paper reports the amount and estimated daily mineral intake of nine elements (Ca, Mg, K, Na, P, Fe, Mn, Cr and Ni) in commercial instant coffees and coffee substitutes (n = 49). Elements were quantified by high-resolution continuum source flame (HR-CS-FAAS) and graphite furnace (HR-CS-GFAAS) atomic absorption spectrometry, while phosphorous was evaluated by a standard vanadomolybdophosphoric acid colorimetric method.Instant coffees and coffee substitutes are rich in K, Mg and P (>100 mg/100 g dw), contain Na, Ca and Fe in moderate amounts (>1 mg/100 g), and trace levels of Cr and Ni. Among the samples analysed, plain instant coffees are richer in minerals (p < 0.001), except for Na and Cr. Blends of coffee substitutes (barley, malt, chicory and rye) with coffee (20–66%) present intermediate amounts, while lower quantities are found in substitutes without coffee, particularly in barley.From a nutritional point of view the results indicate that the mean ingestion of two instant beverages per day (total of 4 g instant powder), either with or without coffee, cannot be regarded as important sources of minerals to the human diet, although providing a supplementation of some minerals, particularly Mg and Mn in instant coffees. Additionally, and for authentication purposes, the correlations observed between some elements and the coffee percentage in the blends, with particular significance for Mg amounts, provides a potential tool for the estimation of coffee in substitute blends.  相似文献   
56.
Consumption of omega-3 fatty acids (ω-3’s), whether from fish oils, flax or supplements, can protect against cardiovascular disease. Finding plant-based sources of the essential ω-3’s could provide a sustainable, renewable and inexpensive source of ω-3’s, compared to fish oils. Our objective was to develop a rapid test to characterize and detect adulteration in sacha inchi oils, a Peruvian seed containing higher levels of ω-3’s in comparison to other oleaginous seeds. A temperature-controlled ZnSe ATR mid-infrared benchtop and diamond ATR mid-infrared portable handheld spectrometers were used to characterize sacha inchi oil and evaluate its oxidative stability compared to commercial oils. A soft independent model of class analogy (SIMCA) and partial least squares regression (PLSR) analyzed the spectral data. Fatty acid profiles showed that sacha inchi oil (44% linolenic acid) had levels of PUFA similar to those of flax oils. PLSR showed good correlation coefficients (R2 > 0.9) between reference tests and spectra from infrared devices, allowing for rapid determination of fatty acid composition and prediction of oxidative stability. Oils formed distinct clusters, allowing the evaluation of commercial sacha inchi oils from Peruvian markets and showed some prevalence of adulteration. Determining oil adulteration and quality parameters, by using the ATR-MIR portable handheld spectrometer, allowed for portability and ease-of-use, making it a great alternative to traditional testing methods.  相似文献   
57.
58.
Water Resources Management - The behavior of a rainwater harvesting system depends on some variables that cannot be controlled, such as rainfall, building roof size and water consumption. The...  相似文献   
59.
The impact of waste disposal on marsh soils was assessed in topsoil samples collected at eight randomly selected points in the salt marsh in Ramallosa (Pontevedra, Spain) at 4-month intervals for 2 years. Polluted soil samples were characterized in physico-chemical terms and their heavy metal contents determined by comparison with control, unpolluted samples. The results revealed a marked effect of waste discharges on the soils in the area, which have low contents in heavy metals under normal environmental conditions. In fact, the studied soils were found to contain substantial amounts of total and DTPA-extractable Cd, Cu, Pb and Zn. Based on the relationship of the redox potential with the DTPA-extractable Cd, Cu, Pb, and Zn contents of the soils, strongly reductive conditions raised the total contents in these elements by effect of their remaining in the soils as precipitated sulphides. Such contents, however, decreased as oxidative conditions gradually prevailed. The contents in DTPA-extractable metals increased with increasing Eh through the release of the metals in ionic form to the soil solution under oxidative conditions. The contents in heavy metals concentrating in the polluted soils were several times higher than those in the control soils (viz. 2 vs. 6 for Cd, 4 vs. 6 for Cu, 4 vs. 20 for Pb, and 2 vs. 15 for Zn, all in mg kg−1). This can be expected to influence the amounts of available heavy metals present in the soils, and hence the environmental quality of the area, in the near future. Based on its geoaccumulation index (Class ≥3 for Cd and Cu, and 1–4 for Pb and Zn), the Ramallosa marsh is highly polluted with Cd and moderately to highly polluted with Cu, Pb and Zn. The enrichment factors obtained confirm that the salt marsh is highly polluted (especially with Cd) as the primary result of anthropic activity.  相似文献   
60.
The one‐pot synthesis and properties of multifunctional hybrid mesoporous organosilica fibers with helical shapes are described. These hybrid mesoporous fibers are prepared without chiral elements and functionalized with a large variety of organic R functions (R = alkylthiols, phenylsulfonates, alkylphosphonates, dansyl, aminopropyl, fluoroalkyl, etc.). The resulting nanomaterials are thoroughly characterized by a variety of techniques. The use of a synergetic combination of achiral molecules as co‐directing structuring agents, a surfactant, and an organofunctional silica precursor R‐Si(OR)3 allows, via carefully tuning of the main synthesis parameters and processing conditions, to control the shape, which is the anisotropic factor, of the hybrid nanofibers. The functionalization of the hybrid materials with fluorescent molecules (dansyl) and gold nanoparticles opens possibilities for sensor and catalytic applications, respectively. Moreover, these hybrid nanofibers can be easily transferred in organic solvents or in a “green” solvent such as water to make stable colloidal dispersions. This tunable functionality of nanofibers also allows their transferability into a variety of polymeric hosts (PVDF, PVBu, and PVP) allowing the formation of functional homogeneous nanocomposite hybrid membranes.  相似文献   
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