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1.
The beneficial effect of a TiO2-based photocatalytic treatment on the indoor air purification of a swine farm has been evaluated in a trial performed in two identical mechanically ventilated traditional weaning units, with 391 animals lodged in each of them. One unit was used as reference, whereas the walls of the second unit (260 m2) were coated with ca. 70 g m(-2) of TiO2 and irradiated with ten UV-A lamps. The environmental parameters (i.e. the ventilation rate, the internal and external temperature and relative humidity), together with NH3, CH4, CO2 and N2O concentrations in the exhaust ducts and PM10 emissions, were monitored in the two units throughout all of the production cycle (75 days). Significant decreases in CH4 concentration (ca. 27%, P < 0.05) and PM10 emission (ca. 17%, P < 0.01) were observed, together with an increase of the piglets' productive performance in the treated unit with respect to the reference one. Indeed, the ADG (Average Daily Gain of piglets) was 424 g vs. 414 g for the piglets lodged in the two units, respectively, with a significantly better feed conversion ratio (FCR, ratio between the food ingested by the animals and their weight gain) of 2.18 vs. 2.44 (P < 0.001). Therefore, the photocatalytic treatment with TiO2 coating had positive effects not only on methane concentration and particulate matter concentration and emission, but also significantly improved the feed conversion ratio of growing piglets, very likely due to the increased quality of indoor air, with positive economic repercussions for the farmer. Internal photocatalytic treatment in swine husbandry could thus be considered as a potential Best Available Technology (BAT).  相似文献   
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The breeding system of a rare Great Lakes endemic, the lakeside daisy ( Hymenoxys acaulis var. glabra ), was investigated when plants from a remnant Illinois population produced no seeds for over 15 years. To determine if the Lakeside daisy was self-incompatible, 20 plants from two populations, Illinois and Ohio, were selfed and outcrossed. Seed/ovule ratios were compared among the different treatments and the location of the incompatibility reaction was identified. Lakeside daisy was found to be self-incompatible (sporophytic). The last Illinois population was effectively extinct because the remaining plants belonged to the same mating type ( N e = 1) and only produced seeds when outcrossed to the Ohio plants. Cross-incompatibility was also observed among Ohio plants, suggesting that within large populations, compatible mating types may be rare locally. In addition, inbreeding depression (lower seed/ovule ratios in inbred than in outcrosses) was observed after one generation of inbreeding. Small populations of self-incompatible species are vulnerable to extinction if the number of self-incompatibility alleles, either as a result of a bottleneck or of genetic drift, falls below tbe number needed for the breeding system to function. Recovery protocols based on these genetic considerations were developed and implemented in 1988 when Lakeside daisy populations were established at three Illinois nature preserves.  相似文献   
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The larval development of the newly discovered cephalocarid from Mediterranean sea, Lightiella magdalenina, was analysed using light and scanning electron microscopy. Twenty-nine larval specimens, divided into 15 metanaupliar and 2 juvenile stages of development, were found. The first six metanaupliar stages had an even number (6, 8, 10, 12, 14 and 16) of trunk segments including telson. The condition of 20 trunk segments, typical of the adult, was reached after another 4 stages by the addition of a single segment per stage. At this tenth stage, the larvae had an incomplete number of trunk limbs. Another five stages were needed to complete the cephalic appendage development, passing from the metanaupliar to the juvenile stage, characterized by loss of the naupliar enditic process of the second antenna. Trunk limbs development was completed during the last two juvenile stages. According to the ontogenetic data reported for Hutchinsoniella macracantha and Lightiella incisa, these seventeen stages probably do not represent the complete developmental series. Nevertheless, they allow us to clarify the main features of cephalocarid ontogeny and show specific differences in the development of both the trunk segments and appendages.  相似文献   
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A bench-scale pilot plant has been developed for the treatment of olive-mill water. The plant is fed in a continuous mode and implements a primary treatment (sand filtering and irradiation with UV-rays) and a secondary treatment (anoxic and aerobic biological treatment). Satisfactory results were obtained and the treated green water falls under the limits of the Italian legislation. Veratric and ferulic acid biodegradation were studied under anoxic conditions in order to verify the requirements for optimal biodegradation. Electronic Publication  相似文献   
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The dissipation of the fungicides captan, cyprodinil, fludioxonil, dithianon, and tebuconazole and of the insecticides chlorpyrifos, fenitrothion, and malathion was studied, following a single treatment of different cultivars of pears, apples, and peaches. The study was conducted in northern Italy, over two successive growing seasons (2004 and 2005). The treatments were performed by the farmers involved, in line with their usual practice. At various time intervals from treatment to harvest, representative samples of fruit were collected and analyzed for pesticide residues. In some cases, concentrations lower than the maximum residue levels (MRLs) were found immediately after treatment. In all trials a rapid decline in pesticide concentrations was observed leading to residues at harvest greatly below the MRLs.  相似文献   
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Laser Induced Breakdown Spectroscopy (LIBS) is a fast and multi-elemental analytical technique particularly suitable for the qualitative and quantitative analysis of heavy metals in solid samples, including environmental ones. Although LIBS is often recognised in the literature as a well-established analytical technique, results about quantitative analysis of elements in chemically complex matrices such as soils are quite contrasting. In this work, soil samples of various origins have been analyzed by LIBS and data compared to those obtained by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The emission intensities of one selected line for each of the five analytes (i.e., Cr, Cu, Pb, V, and Zn) were normalized to the background signal, and plotted as a function of the concentration values previously determined by ICP-OES. Data showed a good linearity for all calibration lines drawn, and the correlation between ICP-OES and LIBS was confirmed by the satisfactory agreement obtained between the corresponding values. Consequently, LIBS method can be used at least for metal monitoring in soils. In this respect, a simple method for the estimation of the soil pollution degree by heavy metals, based on the determination of an anthropogenic index, was proposed and determined for Cr and Zn.  相似文献   
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Background

Over the past 20 years, genetically modified organisms (GMOs) have raised enormous expectations, passionate political controversies and an ongoing debate on how these technologies should be assessed. Current risk assessment procedures generally assess GMOs in terms of their potential risk of negatively affecting human health and the environment. Can this risk-benefit approach deliver a robust assessment of GMOs? In this paper, we question the validity of current risk assessment from both a social and an ecological perspective, and we elaborate an alternative approach, namely in-context trajectory evaluation. This paper combines frame analysis, context analysis and ecosocial analysis to three different case studies.

Results

Applying frame analysis to Syngenta's recent campaign 'Bring plant potential to life', we first de-construct the technosocial imaginaries driving GMOs innovation, showing how the latter endorses the technological fix of socioeconomic problems whilst reinforcing the neoliberal sociopolitical paradigm. Applying context analysis to biopharming in New Zealand, we then explore local practices and knowledge, showing that particularities of context typically omitted from risk assessment processes play a key role in determining both the risks and the potential benefits of a technology. Finally, drawing from the Italian case, we outline through ecosocial analysis how the lack of long-term studies, further aggravated by current methodological deficiencies, prevent risk assessment from considering not only how GMOs affect the environmental context but also, and most importantly, the way people live in, and interact with, this context.

Conclusion

Incorporating frame analysis, context analysis and ecosocial analysis, in the form of in-context trajectory evaluation, into the assessment of GMOs can improve the social compatibility, political accountability and ecological sustainability of its outcomes.  相似文献   
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