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61.
Resource allocation is a fundamental and challenging component of common pool resource governance, particularly transboundary fisheries. We highlight the growing importance of allocation in fisheries governance, comparing approaches of the five tuna Regional Fisheries Management Organizations (tRFMOs). We find all tRFMOs except one have defined resources for allocation and outlined principles to guide allocation based on equity, citizenship, and legitimacy. However, all fall short of applying these principles in assigning fish resources. Most tRFMOs rely on historical catch or effort, while equity principles rarely determine dedicated rights. Further, the current system of annual negotiations reduces certainty, trust, and transparency, counteracting many benefits asserted by rights-based management proponents. We suggest one means of gaining traction may be to shift conversations from allocative rights toward weighting of principles already identified by most tRFMOs. Incorporating principles into resource allocation remains a major opportunity, with important implications for current and future access to fish.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01371-3) contains supplementary material, which is available to authorized users.  相似文献   
62.
Phthalate esters (PEs) have been suspected to be environmental endocrine disruptors and the detailed mechanism remains unclear. The activities of these chemicals can be enhanced through chemical modification under the environmental conditions. We demonstrate that PEs acquire unequivocal estrogenic activity by light exposure. Through UV exposure of an aqueous PE solution, one active photoproduct, identified as 4-hydroxyPE (PE-4OH) based on its characteristic UV and mass spectra, was detected in an estrogen receptor alpha-dependent transactivation assay. PE-4OH was effectively generated by UV 290 nm. The PE-4OH production accompanied H2O2 generation in a UV dose-dependent manner. Both PE and UV irradiation were indispensable in the generation of H2O2. Addition of H2O2 to the PE solution increased PE-4OH production under UV irradiation. The PE-4OH production was also observed in the PE reaction with the Fenton reagent generating hydroxyl radical without UV irradiation. The proposed mechanism for PE-4OH production based on these results is such that by PE-mediated photosensitization H2O2 is generated from O2 and H+ and decomposed to hydroxyl radical, thus oxidizing the PE benzene ring. The PEs-4OH are remarkably active estrogenic products of PEs and would be involved in ER-mediated endocrine disruption.  相似文献   
63.
This study was aimed at investigating the injury mechanism of pedestrian chests in collisions with passenger vehicles of various frontal shapes and examining the influence of the local structural stiffness on the chest injury risk by using the headform impact test at the chest contact area of the vehicle. Three simulations of vehicle to pedestrian collisions were conducted using three validated pedestrian finite element (FE) models of three pedestrian heights of 177 (AM50th), 165 and 150 cm and three FE vehicles models representing a one-box vehicle, a minicar and a medium car. The validity of the vehicle models was evaluated by comparing the headform acceleration against the measured responses from headform impact tests. The chest impact kinematics and the injury mechanisms were analyzed in terms of the distribution of the von Mises stress of the ribcage and in terms of the chest deflections. The chest contact locations on the front panel and the bonnet top were identified in connection to the causation of rib fractures. The risk of rib fractures was predicted by using the von Mises stress distribution. The headform impact tests were carried out at the chest contact area on the front panel and bonnet to examine the safety performance with respect to pedestrian chest protection. In simulations of the one-box vehicle to pedestrian collisions, the chest was struck directly by the frontal structure at a high velocity and deformed substantially, since a shear force was generated by the stiff windshield frame. The acceleration of the headform was related to the rib deflections. The injury threshold of the ribcage deflection (42 mm) corresponded to the headform average acceleration of 68 G. In the minicar collision, the chest was struck with the bonnet top and cowl area at a low velocity, and the deformation was small due to the distributed contact force between the chest and the bonnet top. Besides, the ribcage deformation was too small for bridging a relation between the headform accelerations and rib deflections. In the medium car collision, the deformation mode of the chest was similar to that in the minicar collision. The chest collided with the bonnet top at a low velocity and deformed uniformly. The deflection of the ribs had an observable correlation with the headform accelerations measured in the headform impact tests. The frontal shape of a vehicle has a large influence on a pedestrian’s chest loadings, and the chest deformation depends on the size of the pedestrian and the stiffness of the vehicle. The one-box passenger vehicle causes a high chest injury risk. The headform impactor test can be utilized for the evaluation of the local stiffness of a vehicle’s frontal structure. The reduction of the headform acceleration is an effective measure for pedestrian chest protection for specific shapes of vehicles by efficacy in modifying the local structural stiffness.  相似文献   
64.
This paper has developed a method for forecasting the future paths of genuine savings (GS) with and without carbon dioxide (CO2) emissions constraints. GS calculations require shadow prices, which can be endogenously determined for variables and constraints in a model. However, in case of a ‘business as usual’ model (BAU), the shadow prices required for calculating GS without constraints show theoretically zero. This research derives the shadow prices required to measure GS for the BAU case as a function of several variables available in the optimal (economically efficient) case. This function is estimated from endogenously obtained variables from a model with environmental constraints. Subsequently, this function is used to calculate shadow prices with and without CO2 constraints, which are further employed to compute future paths of GS according to two methods applied in the papers by Arrow et al. We successfully estimated GS (or GSnt; GS with changes in population and technology) under the BAU case, however, suggest that GS (or GSnt) measures depend, to a great extent, on the time span under consideration (truncation year) for wealth accounting and the accounting methods by Arrows’ papers used for its estimation. In some cases, especially according to the methodology used by Arrow’s paper in 2004 using adjusted consumption in wealth accounting, the sign of GS (or GSnt) changes from negative to positive when changes in total factor productivity are taken into consideration. These aspects should be explored before measuring (un)sustainability of a particular path based on the GS (or GSnt) indicator.  相似文献   
65.
Transformation of diphenylarsinic acid in agricultural soils   总被引:1,自引:0,他引:1  
We investigated the transformation and fate of diphenylarsinic acid (DPAA) during incubation in two types of soils (Entisol and Andisol) under aerobic and anaerobic conditions. Under anaerobic conditions only, DPAA was transformed into methyldiphenylarsine oxide by methylation. Under both aerobic and anaerobic conditions, DPAA was degraded to phenylarsonic acid by dephenylation, and phenylarsonic acid was subsequently methylated to form methylphenylarsinic acid and dimethylphenylarsine oxide. The degradation of DPAA in the Andisol was less extensive than in the Entisol. In autoclaved soil under anaerobic conditions, DPAA underwent little degradation during the 24-wk incubation. In unautoclaved soils, the concentration of DPAA in soil clearly decreased after 24 wk of incubation, indicating that DPAA degradation was driven by microbial activity.  相似文献   
66.
The potential to use the results of biochemical acid potential (BAP) tests to predict the ultimate digestibility of raw and pretreated waste activated sludge (WAS) was investigated. The ultimate methane production from biochemical methane potential (BMP) tests on raw and pretreated samples which spanned a range of biodegradability proved linearly related to the volatile fatty acid (VFA) and soluble chemical oxygen demand (COD) production in corresponding BAP tests. In addition, a linear relationship between NH4-N production in the BMP and BAP tests was observed. Despite the linear nature of the relationships, the ratio of the production of methane in the BMP tests to the production of VFAs in the BAP tests varied with the biodegradability of the sludge samples. Waste Activated Sludge samples with low digestibility had ultimate yields of CH4 that were greater than the VFA yields in BAP tests, whereas sludge samples with high digestibility had lower yields of CH4 than the corresponding VFA yields. This trend contrasted with the NH4 results, in which the yields in the BAP tests were consistently less than those observed in the BMP tests. It was hypothesized that the varying relationship between CH4 and VFA yields was because of the inhibition of anaerobic oxidation of long-chain fatty acids (LCFAs) in the BAP tests. Long-chain fatty acids would be converted to CH4 in BMP tests but produced as digestion intermediates in the BAP tests and were not measured as part of the VFA yield. Hydrogen and acetate were identified as the two most likely intermediates that would accumulate in the BAP tests (which would cause inhibition). A stoichiometric model to facilitate the development of an improved understanding of the biodegradation processes in the BAP and BMP tests was assembled. When the model was applied to the BAP tests the anaerobic oxidation of LCFAs and propionate and methanogenesis were excluded from the model. The model was employed to estimate the extent of degradation of lipids, carbohydrates, and proteins in the batch tests as a function of the ultimate biodegradability of the sludge samples. On the basis of model fitting, it was determined that the degradation of lipids in BMP tests decreased, whereas the degradation of carbohydrates and proteins increased as the digestibility of the sludge samples increased. The varying ratio of lipid to protein and carbohydrate degradability with increasing digestibility of the sludge samples describes the relationship between VFA production and CH4 production in the BAP, and BMP tests, respectively.  相似文献   
67.
This study investigated the effects of hygiene indicator bacteria during the biostimulation of groundwater contaminated with chlorinated ethene. We showed the state of dechlorination activity and behavior of microbial structure by the addition of Escherichia coli (E. coli) as hygiene indicator bacteria in a contaminated groundwater sample. Dechlorination of tetrachloroethene and trichloroethene to cis-1,2-dichloroethene (cis-DCE) within 14 days took place similarly both with and without the addition of E. coli. This indicated that inhibition of against dechlorinating activity of corresponding dechlorinating bacteria was not caused by E. coli. Structural change of the bacterial community was analyzed both before and after dechlorination using a denaturing gradient gel electrophoresis (DGGE) and clone library. The result of DGGE detected E. coli only at day 0. A sample at day 14 after dechlorination detected Pseudomonas putida, Anaerosinus glycerini, and Clostridium genus but not E. coli. The result of the clone library also showed an identical profile. Detection of E. coli using desoxycholate media was decreased from 2.3 × 106 cells/ml to 6.0 × 103 cells/ml during day 14. These results suggest that biostimulation of groundwater contaminated by chlorinated ethene in the presence of hygiene bacteria caused the dechlorination without activity inhibition and decrease of dechlorinating bacteria.  相似文献   
68.
69.
Temporal and spatial variations in concentrations of particle-associated polycyclic aromatic hydrocarbons (PAHs) and their nitrated and oxygenated derivatives (nitro-PAHs and oxy-PAHs) were investigated to assess the influence of secondary formation on atmospheric occurrences of oxy-PAHs associated with particulate matter in downtown Tokyo, Japan. The daily variation in concentration of 1,8-naphthalic anhydride (1,8-NA) in summer 2007 was similar to that for 2-nitrofluoranthene (2-NF), a representative secondary formed nitro-PAH, while the variation for benzanthrone (BA) was similar to PAHs. In addition, the concentrations of polycyclic aromatic compounds (PACs) associated with airborne particulate matter decreased in the order of PAHs > BA > 9-fluorenone (9-FO) or 9,10-anthraquinone (9,10-AQ) > 1,8-NA with an increase in distance from the roadside, whereas 2-NF was constant. These results suggest that a considerable fraction of some oxy-PAHs such as 1,8-NA associated with airborne particulate matter in downtown Tokyo originates from atmospheric secondary formation.  相似文献   
70.
Bottom sediments from Nakaumi Lagoon and the Honjo Area in southwest Japan were analyzed to determine their geochemical compositions and to assess potential impacts by comparison with sediment quality guidelines. Present-day water quality was also assessed. Results showed that the water quality of Nakaumi Lagoon and the Honjo area contrasts between their upper and lower parts. Average abundances of As, Pb, Zn, Cu, Ni, and Cr in the Nakaumi sediments were 12, 25, 135, 32, 21, and 46 ppm, respectively, compared to 10, 24, 110, 26, 20, and 38 ppm in the Honjo area. All averages are greater than those of the upper continental crust. The elevated metal concentrations are probably related to the fine-grained nature of the sediments, reducing bottom conditions produced by abundant organic matter and possibly minor non-point anthropogenic sources. Trace metal contents are strongly correlated with Fe2O3, suggesting that Fe oxides play a role in controlling abundances. Metal concentrations exceed the NYSDEC lowest effect level and CCME interim sediment quality guidelines that indicate moderate impact on aquatic organisms. Average abundances of As and Zn are comparable to the Coastal Ocean Sediment Database threshold, whereas maximum concentrations exceed that value, indicating that the concentrations of these metals are potentially toxic. These enrichments suggest that regular monitoring may be desirable even where no point sources of metal pollution exist.  相似文献   
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