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111.
Franco JL Posser T Mattos JJ Sánchez-Chardi A Trevisan R Oliveira CS Carvalho PS Leal RB Marques MR Bainy AC Dafre AL 《Marine environmental research》2008,66(1):88-89
The aim of this study was to investigate biochemical changes in juvenile carp (Cyprinus carpio) exposed to zinc chloride (10, 30 and 100 microM) for a period of 48 h. Zinc exposure caused a concentration-dependent reduction in glutathione reductase (GR) activity in gills, liver and brain. Gill glutathione S-transferase (GST) was reduced when animals were exposed to the highest concentration of 100 microM zinc. The phosphorylation of p38(MAPK) increased in the brain of fish exposed to zinc 100 microM, while phosphorylation of the extracellular signal-regulated protein kinase 1/2 (ERK1/2) and c-Jun N-terminal protein kinase 1/2 (JNK1/2) remained unchanged. Expression of proteins HSP60 and HSP70 were not affected by zinc exposure. Considering the significant concentration-dependent inhibition of GR in all tissues analyzed, this enzyme could be a potential biomarker of exposure to zinc, which has to be confirmed. 相似文献
112.
Rethinking small-scale fisheries compliance 总被引:3,自引:1,他引:2
Fisheries compliance has been identified as key to sustainable fisheries management. However, it has been widely acknowledged that the approach by many governments worldwide to achieve compliance is largely through law enforcement efforts. Although theories of normative action have expanded compliance thinking from that of rationalist approaches, this paper takes the argument further. By drawing on criminology and security discourse, and on empirical research on small-scale fisheries in South Africa, this paper argues for a new approach to our understanding of compliance. Furthermore, it argues that rather than taking law as given, the formation of law and the power dynamics influencing such processes are critical aspects that need to be acknowledged and understood in fisheries compliance theory. 相似文献
113.
The topic of ship recycling has obtained considerable attention during the last two decades for a variety of reasons with the likelihood of the adoption of a new international convention under the auspices of the International Maritime Organization (IMO). This study applies econometric modeling to a unique data set to provide insight into the dynamics of the ship recycling market. The data set contains information on 51,112 ships over 100 gt and includes 748,621 events over a period of 29 years. The analysis confirms a negative relationship of earnings and a positive relationship of scrap prices for all locations while Bangladesh seems to be more sensitive to changes in earnings than the other locations and more likely demolishes larger and older vessels. The results for flag and ownership vary across scrapping locations with Malta and Cyprus indicating potential importance from a registry perspective. The overall safety profile of a vessel seems to be less important towards the probability of a ship being scrapped. Possible implementation of the convention at EU level will mostly likely affect Turkey while non-ratification of one of the major flags will most likely affect China or Bangladesh. 相似文献
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116.
Caroline Faria Bisola Falola Jane Henderson Rebecca Maria Torres 《The Professional geographer》2019,71(2):364-376
Despite decades of recognition and worry about diversity, our discipline remains persistently white. That is, it is dominated by white bodies and it continues to conform to norms, practices, and ideologies of whiteness. This is a loss. At best, it limits the possibilities and impact of our work as geographers. At worst, it perpetuates harmful exclusions in our discipline: its working environments, its institutions, and its knowledge production. This remains deeply concerning for many geographers, and there has been important research, commentary, and institutional activity over the years. Yet, research shows us that little meaningful progress has been made. We know that mentoring is one vital part of the journey toward change. As such, we reflect here on our experience developing a research collective built on a transformative mentoring practice. We outline the key challenges, strategies, and tentative successes of the collective in supporting women of color undergraduate, graduate, and faculty geographers, arguing that such feminist formations are a vital part of the path to intellectual racial justice in our field. Key Words: diversity, feminist geography, higher education, mentoring, race. 相似文献
117.
Pier Luigi Sacco Maria Tartari Guido Ferilli Giorgio Tavano Blessi 《Urban geography》2019,40(4):529-554
In this paper, we critically examine the role of artistic locational choices and practices in the context of gentrification processes in urban renewal contexts. We characterize gentrification as a form of domestication of space, and explore the extent to which artistic choices and practices relate to such process with reference to the deontological dilemma of legitimization within the art system vs. responsible empowerment of vulnerable local constituencies. We illustrate our argument with an analysis of the High Line Art project, and show how this can be considered as a textbook example of art-driven space domestication leading to brutal forms of gentrification. We comment on the threat that this provides to the social credibility of artistic practices as an agency of responsible social change. 相似文献
118.
Houda El Kerni Hasnaa Chennaoui Aoudjehane David Baratoux Mohammed Aoudjehane Andr Charrire Hassan Ibouh Pierre Rochette Yoann Quesnel Minoru Uehara Thomas Kenkmann Gerwin Wulf Michael Poelchau Van Binh Nguyen Maria Aboulahris Samira Makhoukhi Georges Aumaître Didier Bourls Karim Keddadouche 《Meteoritics & planetary science》2019,54(10):2483-2509
Since the discovery of shatter cones (SCs) near the village of Agoudal (Morocco, Central High Atlas Mountains) in 2013, the absence of one or several associated circular structures led to speculation about the age of the impact event, the number, and the size of the impact crater or craters. Additional constraints on the crater size, age, and erosion rates are obtained here from geological, structural, and geophysical mapping and from cosmogenic nuclide data. Our geological maps of the Agoudal impact site at the scales of 1:30,000 (6 km2) and 1:15,000 (2.25 km2) include all known occurrences of SCs in target rocks, breccias, and vertical to overturned strata. Considering that strata surrounding the impact site are subhorizontal, we argue that disturbed strata are related to the impact event. Three types of breccias have been observed. Two of them (br1‐2 and br2) could be produced by erosion–sedimentation–consolidation processes, with no evidence for impact breccias, while breccia (br1) might be impact related. The most probable center of the structure is estimated at 31°59′13.73?N, 5°30′55.14?W using the concentric deviation method applied to the orientation of strata over the disturbed area. Despite the absence of a morphological expression, the ground magnetic and electromagnetic surveys reveal anomalies spatially associated with disturbed strata and SC occurrences. The geophysical data, the structural observations, and the area of occurrence of SCs in target rocks are all consistent with an original size of 1.4–4.2 km in diameter. Cosmogenic nuclide data (36Cl) constrain the local erosion rates between 220 ± 22 m Ma?1 and 430 ± 43 m Ma?1. These erosion rates may remove the topographic expression of such a crater and its ejecta in a time period of about 0.3–1.9 Ma. This age is older than the Agoudal iron meteorite age (105 ± 40 kyr). This new age constraint excludes the possibility of a genetic relationship between the Agoudal iron meteorite fall and the formation of the Agoudal impact site. A chronolgy chart including the Atlas orogeny, the alternation of sedimentation and erosion periods, and the meteoritic impacts is presented based on all obtained and combined data. 相似文献
119.
The Swiss stone Pine (Pinus cembra L.) is an alpine species, fairly commonly occurring in the Alps and the Carpathians, close to the timberline. Natural sites of the Swiss stone pine in Poland are found exclusively in the Tatra Mountains, within the area of the Tatra National Park (TNP). In 2017, the health status of the needles of P. cembra was determined and their mycological analysis was carried out. As a result, 11 species of fungi were isolated from the needles showing disease symptoms, manifested by various shades of discoloration. The most frequently observed species was Fusarium oxysporum. It probably does not bring on disease symptoms, but may affect the development of other frequently isolated species (such as Sydowia polyspora, Lophodermium sp. and Lophodermium conigenum) that are pathogenic to Pinus spp. 相似文献
120.
Anna Belfer-Cohen 《Geoarchaeology》1996,11(5):428-436