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51.
Climate change presents a threat to the sustainability of cities and their societies, and must be adequately addressed. Urban environments (cities) are responsible for the creation of a significant amount of greenhouse gas emissions which are the source of climate change. Cities have been increasingly the focus of action to address climate change, yet emissions are not significantly reducing. Additionally, there a lack of integration between adaptation and mitigation. This prevents responses adequate to limit global warming to 1.5OC, and to be well adapted to anticipated changes. This paper critically analyses existing definitions and typologies of climate change actions. A definition of ‘climate change transformation’ is proposed which includes the integration of adaptation and mitigation goals to enable a new regime in which global warming is limited to 1.5OC. A new three-part typology: ‘coping, malaction and transformation,’ is presented for categorising climate change actions by the extent to which they integrate adaptation and mitigation, and define a new regime. The typology is accompanied by illustrations to demonstrate the relationship between adaptation and mitigation. The definition, typology and illustration serve to guide effective climate change decision making, and provides principles to guide application in urban environments.  相似文献   
52.
One of the main challenges of international environmental agreements is improving relevant policy actions to promote adequate environmental responses. To support the work of decision makers, recent studies have used environmental and social indicators to construct global and regional-scale indices. This study aimed to use the Ocean Health Index and the Management Ranking for Brazilian States to assess Brazil’s performance regarding the Aichi Biodiversity Targets (ABTs) for coastal and marine ecosystems. Thus, six ABTs were matched and their performance was evaluated. These ABTs focused on the following topics: pollution, fish and invertebrate stocks, pressures on coral, threatened species and their conservation, the contribution of biodiversity to carbon stocks and the national biodiversity strategy and action plan. However, although the indices used showed many pathways to explore how Brazil is performing, it is still complex to evaluate ABTs’ performance regarding coastal and marine ecosystems at a global and regional scale.  相似文献   
53.
Viral hemorrhagic septicemia virus (VHSV) and marine birnavirus (MABV) are the causative pathogens for some of the most explosive epidemics of emerging viral diseases in many Asian countries, leading to huge economic losses in aquaculture. Rapid molecular detection for surveillance or diagnosis has been a critical component in reducing the prevalence of pathogen infection. The loop-mediated isothermal amplification (LAMP) of DNA is currently one of the most commonly used molecular diagnostic tools, as it is simple, quick, and easy to amplify target DNA under isothermal conditions. In the present study, a novel and highly specific LAMP assay for the sensitive and rapid detection of VHSV and MABV infection in fish was developed. Using a set of synthesized primers matching a specific region of the genome, the efficiency and specificity of the LAMP assay were optimized in terms of the reaction temperature and DNA polymerase concentration, as they are the main determinants of the sensitivity and specificity of the LAMP assay. In particular, we demonstrated that our assay could be applied to efficient detection of VHSV and MABV infection in the wild fish, Paralichthys olivaceus. Our results demonstrate the simplicity and convenience of this method for the detection of viral infection in aquatic organisms.  相似文献   
54.
The biosorption of copper (II) from aqueous solution using different bacterial strains was studied. Copper-biosorbing bacteria were isolated from tannery effluent collected from Borg Al-Arab, Alexandria, Egypt. These isolates displayed different degrees of copper biosorption under aerobic conditions. Based on 16S rDNA gene sequence analysis, three of them (S2, S5 and S7) were identified as Chryseobacterium sp., Enterobacter sp. and Stenotrophomonas sp., respectively. Initial copper (II) ion concentrations from 25–250 mg/L at constant temperature 30 °C were studied. The residual copper (II) concentration and its toxicity effect in solution were determined using atomic absorption spectrophotometer and bioluminescent bioreporter. The bioluminescence inhibition of strain (S5) reached to 91.4 % as compared with the strain (S7) reached to 83.3 % at 225 mg/L of copper ion where the maximum biosorption efficiency for S5 and S7 were 71 % and 70.1 % correspondingly using atomic absorption. The bioluminescent bioreporter was proved to be fast and accurate technique for measurement the toxicity effect of residual copper (II) in solution.  相似文献   
55.
A brief presentation is made of the concept of the Exclusive Economic Zone (EEZ) adopted by the United Nations Conference on the Law of the Sea, and included as a major feature of the Law of the Sea. The potential of the EEZ for the small developing island countries is discussed, together with the possibility of using the EEZ to achieve a larger measure of equity among nations than the prevailing one. The role of the EEZ in obtaining improved ocean governance, more sustainable management of the marine resources and control of marine pollution is considered. The need for building an indigenous capacity to deal with the marine resources and issues is identified and the possibility of achieving this through regional cooperation. The possibilities inherent in the EEZ regime for oceanic islands are discussed, with focus on the Indian Ocean, the Mediterranean and the central Atlantic Ocean.  相似文献   
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