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31.
Participatory modeling is increasingly recognized as an effective way to assist collective decision-making processes in the domain of natural resource management. This article introduces a framework for evaluating projects that have adopted a participatory modeling approach. This evaluation framework—known as the “Protocol of Canberra”—was developed through a collaboration between French and Australian researchers engaged in participatory modeling and evaluation research. The framework seeks to assess the extent to which different participatory modeling initiatives not only modify perceptions among and interactions between participants, but also contribute to collective decision-making. The article discusses the development of the framework and it’s application to three case-studies, two from Australia and one from the Pacific Island of the Republic of Kiribati. The article concludes with some comments for future use of the framework in a range of participatory modeling contexts.  相似文献   
32.

Background  

Environmental agencies have to take measures to either reduce discharges and emissions of nitrate or to remediate nitrate-polluted water bodies where the nitrate concentrations exceed threshold values. Isotope data can support the identification of nitrate pollution sources and natural attenuation processes of nitrate.  相似文献   
33.
The evaluation of radioactivity accidentally released into the atmosphere involves determining the radioactivity levels of rainwater samples. Rainwater scavenges atmospheric airborne radioactivity in such a way that surface contamination can be deduced from rainfall rate and rainwater radioactivity content. For this purpose, rainwater is usually collected in large surface collectors and then measured by γ-spectrometry after such treatments as evaporation or iron hydroxide precipitation. We found that collectors can be adapted to accept large surface (diameter 47 mm) cartridges containing a strongly acidic resin (Dowex AG 88) which is able to quantitatively extract radioactivity from rainwater, even during heavy rainfall. The resin can then be measured by γ-spectrometry. The detection limit is 0.1 Bq per sample of resin (80 g) for 137Cs. Natural 7Be and 210Pb can also be measured and the activity ratio of both radionuclides is comparable with those obtained through iron hydroxide precipitation and air filter measurements. Occasionally 22Na has also been measured above the detection limit. A comparison between the evaporation method and the resin method demonstrated that 2/3 of 7Be can be lost during the evaporation process. The resin method is simple and highly efficient at extracting radioactivity. Because of these great advantages, we anticipate it could replace former rainwater determination methods. Moreover, it does not necessitate the transportation of large rainwater volumes to the laboratory.  相似文献   
34.
Two thermophilic digesters were inoculated with manure and started-up under mixed and stagnant conditions. The Archaea in the mixed digester (A) were dominated by hydrogenotrophic Methanobateriaceae (61%) with most of the methane being produced via syntrophic pathways. Methanosarcinales (35%) were the only acetoclastic methanogens present. Acetate dissipation seems to depend on balanced hydrogenotrophic-to-acetotrophic abundance, which in turn was statistically correlated to free ammonia levels. Relative abundance of bacterial community was associated with the loading rate. However, in the absence of mixing (digester B), the relationship between microbial composition and operating parameters was not discernible. This was attributed to the development of microenvironments where environmental conditions are significantly different from average measured parameters. The impact of microenvironments was accentuated by the use of a non-acclimated seed that lacks adequate propionate degraders. Failure to disperse the accumulated propionate, and other organics, created high concentration niches where competitive and inhibiting conditions developed and favored undesired genera, such as Halobacteria (65% in B). As a result, digester B experienced higher acid levels and lower allowable loading rate. Mixing was found necessary to dissipate potential inhibitors, and improve stability and loading capacity, particularly when a non-acclimated seed, often lacking balanced thermophilic microflora, is used.  相似文献   
35.
36.
The saddle gall midge, Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae), has undergone a resurgence recently as a pest of cereals in Belgium and other European countries. An effective monitoring tool of saddle gall midge flights is needed to understand the enigmatic population dynamics of this pest, and to design an integrated management strategy. Therefore, volatile compounds emitted by females (alkan-2-ols and alk-2-yl butanoates) were identified, and the chirality of the emitted esters was determined to be the R absolute configuration. In field-trapping experiments, racemic non-2-yl butanoate attracted substantial numbers of H. marginata males. Thus, this compound will be useful in baited traps for monitoring seasonal flight patterns, and improving integrated management of the saddle gall midge in agricultural systems.  相似文献   
37.
Environmental Science and Pollution Research - Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using...  相似文献   
38.
In recent decades, many toxicological tests based on in vivo or in vitro models, mainly from mammalian (rat–mouse) and fish species, were used to assess the risks raised by contact or ingestion of molecules of pharmaceutical, agricultural, or natural origin. But no, or few, in vitro tests using other non-mammalian models such as bird have been explored despite their advantages: the embryonic gonads of birds have a high plasticity of development sensitive to estrogen, and sperm production is nearly two times faster than in rodents. Hence, we have established an in vitro culture of germ cells and somatic cells from chicken post-natal testis, and we have evaluated the sensitivity against the endocrine disruptor compound mono-(2-ethylhexyl) phthalate (MEHP) in comparison to previous studies using rodent and human models. After 96 h of exposure in presence of 10 μM MEHP, chicken seminiferous tubules cultures present a structural alteration, a reduction in cell proliferation and in germ cells population. Apoptosis of germ and somatic cells increases in presence of 1 μM MEHP. Furthermore, MEHP does not affect inhibin B and lactate production by Sertoli cells. These results are in accordance with previous studies using rat, mice, or human culture of testicular cells and in similar range of exposures or even better sensitivity for some “end-points” (biological parameters). In conclusion, the establishment of this postnatal testicular cells culture could be considered as an alternative method to in vivo experiments frequently used for evaluating the impact on the terrestrial wildlife species. This method could be also complementary to mammal model due to the limiting number of animals used and its elevated sensitivity.  相似文献   
39.
We present two new software implementations of the BETR Global multimedia contaminant fate model. The model uses steady-state or non-steady-state mass-balance calculations to describe the fate and transport of persistent organic pollutants using a desktop computer. The global environment is described using a database of long-term average monthly conditions on a 15° × 15° grid. We demonstrate BETR Global by modeling the global sources, transport, and removal of decamethylcyclopentasiloxane (D5).  相似文献   
40.
RASA1-related disease is a rare autosomal dominant disease characterized by capillary malformations, arteriovenous malformations (AVMs), and/or arteriovenous fistulas (AFVs). Penetrance is nearly complete and vascular malformations may cause serious complications such as organ injury due to oxygenation disorder, brain abscess, hemorrhage, and stroke. Early diagnosis is useful in order to discuss optimal management, including AVMs/AVFs embolization or surgical procedures, and try to prevent some of the complications. In this context, molecular testing of RASA1 gene mutation in relatives may help to better manage the family. All arteriovenous malformations are however not accessible to such procedures. In addition, these therapeutic procedures may result in potential side effects and complications. A couple was referred to our genetics unit and asked us for prenatal genetic testing about a RASA1 mutation. Here, we discuss about arguments that led our team to accept prenatal testing. To the best of our knowledge, no molecular prenatal diagnosis was reported until now in RASA1-related diseases. This first report of prenatal diagnosis in RASA1-related diseases may also offer perspectives for a more general discussion in the field of inherited arteriovenous malformations.  相似文献   
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