Enzyme-linked immunosorbent assay for bisphenol A: Assay optimization and its application for surface water analysis

A range of ELISAs in indirect and direct formats for the determination of bisphenol A (BPA) was developed. Bisphenol A carboxymethyl ether (BPA-CME), (BPA-CPE) and 4,4-bis(4-hydroxyphenyl)valeric acid were coupled with bovine serum albumin (BSA) (immunogens for the production of polyclonal antibodies), ovalbumin (OVA) and horseradish peroxidase. In general, the indirect assay was more sensitive and specific than the direct one. Using heterologous combinations of immunoreagents in the indirect assay allowed to increase assay sensitivity and specificity. The highest sensitivity was obtained for the antibodies produced against a conjugate of BPA-CPE with BSA and a conjugate of 4,4-bis(4-hydroxyphenyl)valeric acid with OVA. The detection limit of BPA in phosphate buffer was 0.03?ng?mL^?1. The assay developed was also the most specific towards BPA. Maximum cross-reactivity values did not exceed 11% for 4-cumylphenol, 5% for bisphenol E and 2% for bisphenol S. Finally, the developed assay was used to analyze surface water samples spiked with known amount of BPA. The assay showed good recovery values (85–109%) for surface water with mineralization level lower than 500?mg?L^?1.     

Correction to: Documenting lemming population change in the Arctic: Can we detect trends?

Ambio - In the original published article, some of the symbols in figure 1A were modified incorrectly during the typesetting and publication process. The correct version of the figure is provided...     

Estimating the potential of greenhouse gas mitigation in Kazakhstan

As part of the studies related to the obligations of the UN Framework Convention on Climate Change, the Republic of Kazakhstan started activities to inventory greenhouse gas (GHG) emissions and assess of GHG mitigation options. The objective of this paper is to present an estimate of the possibility of mitigating GHG emissions and determine the mitigation priorities. It presents a compilation of the possible options and their assessment in terms of major criteria and implementation feasibility. Taking into account the structure of GHG emissions in Kazakhstan in 1990, preliminary estimates of the potential for mitigation are presented for eight options for the energy sector and agriculture and forestry sector. The reference scenario prepared by expert assessments assumes a reduction of CO₂ emissions in 1996–1998 by about 26% from the 1990 level due to general economic decline, but then emissions increase. It is estimated that the total potential for the mitigation of CO₂ emissions for the year 2000 is 3% of the CO₂ emissions in the reference scenario. The annual reduction in methane emissions due to the estimated options can amount to 5%–6% of the 1990 level.

     

Land Degradation on Barren Hills: A Case Study in Northeast Vietnam

The term "barren hills" has been a keyword for land degradation in the uplands of Vietnam for over a decade. Nevertheless, the "barren" land is still not adequately ecologically characterized. In this work, we analyze land use-induced changes in vegetation and soil properties along a sequence of barren hills types formed on one physiotope. The study is undertaken in the Bac Kan province, one of the poorest upland regions where livestock plays an important role. A transition from an old-growth laurel forest to a sparse manmade grassland is characterized by a total of 177 species, rapid species turnover, and discrete dominants, and an overwhelming effect of disturbance history on both soil and vegetation patterning. Land degradation is most apparent in land use-induced maintenance of arrested successions, and the regeneration course is shifted towards drier formations. We hypothesize a conceptual model as an aid to understanding the process of early fallow differentiation in response to the patterned, fine-scale disturbances. The larger-scale implications of the observed trends in regeneration potentials deviation, and, in particular, the effect of water buffaloes in halting fallow successions, are discussed.     

Persistent organic pollutants in soils and sediments from James Ross Island, Antarctica

Soil and sediment samples from James Ross Island were analyzed for their PCB, OCP and PAH contents. Soil concentrations ranged between 0.51 and 1.82 ng g(-1) for seven indicator PCB congeners, between 0.49 and 1.34 ng g(-1) for HCH congeners, between 0.51 and 3.68 ng g(-1) for the sum of p,p'-DDT, DDE, and DDD, and between 34.9 and 171 ng g(-1) for the sum of 16 EPA PAHs. Sediment levels from 0.32 to 0.83 ng g(-1) were found for PCBs, from 0.14 to 0.76 ng g(-1) for HCHs, from 0.19 to 1.15 ng g(-1) for DDTs, and from 1.4 to 205 ng g(-1) for PAHs. A prevalence of low-mass PAHs, less chlorinated PCBs, and more volatile chemicals indicates that the long-range atmospheric transport from populated areas of Africa, South America, and Australia is the most probable contamination source for the solid matrices in James Ross Island.     

Assessing drivers of post-harvest losses: tangible and intangible resources’ perspective

Environment, Development and Sustainability - Many stakeholders in agro-food industry are concerned about sustainability, especially in addressing post-harvest loss (PHL). However, resources...     

核桃果皮基活性炭对甲基橙和酸性品红的吸附性能

采用氯化锌活化法制得核桃果皮基活性炭吸附甲基橙和酸性品红,考察了吸附时间,p H,吸附质初始浓度对吸附性能的影响及吸附热力学和动力学性质。结果表明,核桃果皮基活性炭是吸附甲基橙和酸性品红染料的理想材料;延长吸附时间,去除率和吸附量增加,最佳吸附时间为6 h;减小p H值,去除率和吸附量增加。p H为6时,2种染料的去除率达95%以上,吸附效果较好;增大吸附质初始浓度,去除率降低,吸附量增大,当甲基橙初始浓度为180 mg/L时,吸附基本达到饱和;甲基橙的吸附属于单层吸附,酸性品红的吸附属于多层吸附行为。准二级动力学方程均能较好地解释2种染料的吸附动力学行为。     

The Governance of the Mitigation of the Baltic Sea Eutrophication: Exploring the Challenges of the Formal Governing System

This article focuses on the governing system of the mitigation of eutrophication in the Baltic Sea. Policies and measures of the Baltic Sea coastal countries, the macro--regional (HELCOM) level, and the level of the European Union are described and governance challenges explicated. We found that the main challenges at different governance levels include: differences between coastal countries in terms of environmental conditions including environmental awareness, overlaps of policies between different levels, the lack of adequate spatial and temporal specification of policies, and the lack of policy integration. To help to meet these challenges, we suggest closer involvement of stakeholders and the public, the improvement of the interplay of institutions, and the introduction of a “primus motor” for the governance of the mitigation of eutrophication in the Baltic Sea.     

Circulation and Stream Plume Modeling in Conesus Lake

A three-dimensional hydrodynamic model that includes the effect of drag from macrophytes was applied to Conesus Lake to study the seasonal circulation and thermal structure during spring and early summer. Local weather conditions and stream flow data were used to drive the model. The drag coefficient for macrophytes was calculated as a function of leaf density. In general, the model results show good agreements with the observations, including vertical temperature profiles measured at two locations and average surface temperature derived from calibrated thermal imagery for large-scale simulations of the entire lake. Additional high-resolution simulations were carried out to understand water circulation and transport of sediment and model-generated tracer during hydrometeorological events at stream mouths for two experimental sites. The model results show that the plume development at stream mouths during storm events in Conesus Lake are site-dependent and may either be current- or wind-driven. The results also show a significant effect from the presence of macrophytes on sediment deposition near stream mouths.