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The Indian Ocean Experiment (INDOEX) was an international, multiplatform field campaign to measure long-range transport of air pollution from South and Southeast Asia toward the Indian Ocean during the dry monsoon season in January to March 1999. Surprisingly high pollution levels were observed over the entire northern Indian Ocean toward the Intertropical Convergence Zone at about 6°S. We show that agricultural burning and especially biofuel use enhance carbon monoxide concentrations. Fossil fuel combustion and biomass burning cause a high aerosol loading. The growing pollution in this region gives rise to extensive air quality degradation with local, regional, and global implications, including a reduction of the oxidizing power of the atmosphere.

Corporate social performance (CSP) is assumed to have a positive impact on macroeconomic sustainability, but empirical evidence of this impact is absent in the literature. The objective of this paper is to investigate the macro impacts of CSP. We first establish a conceptual framework on the relationship between CSP at the individual business level and sustainability at the macro level. Next, we empirically test the relationship between (averaged) CSP scores and greenhouse gas emissions at the macro level for 22 countries during 20042011. We use Granger causality tests to check for Granger causality. The estimation results show that CSP reduces greenhouse gas emissions, but the long-term effect is rather modest.

Plants and cyanobacteria use the chlorophylls embedded in their photosystems to absorb photons and perform charge separation, the first step of converting solar energy to chemical energy. While oxygenic photosynthesis is primarily based on chlorophyll a photochemistry, which is powered by red light, a few cyanobacterial species can harness less energetic photons when growing in far-red light. Acclimatization to far-red light involves the incorporation of a small number of molecules of red-shifted chlorophyll f in the photosystems, whereas the most abundant pigment remains chlorophyll a. Due to its different energetics, chlorophyll f is expected to alter the excited-state dynamics of the photosynthetic units and, ultimately, their performances. Here we combined time-resolved fluorescence measurements on intact cells and isolated complexes to show that chlorophyll f insertion slows down the overall energy trapping in both photosystems. While this marginally affects the efficiency of photosystem I, it substantially decreases that of photosystem II. Nevertheless, we show that despite the lower energy output, the insertion of red-shifted chlorophylls in the photosystems remains advantageous in environments that are enriched in far-red light and therefore represents a viable strategy for extending the photosynthetically active spectrum in other organisms, including plants. However, careful design of the new photosynthetic units will be required to preserve their efficiency.

Roundtables for sustainable beef have evolved in national contexts as well as at the global level as a multi-stakeholder process to address sustainability concerns in the cattle sector. However, due to their relatively recent inception, the literature on the beef roundtables is extremely limited and very little scholarly work has traced their process or impact. We used semi-structured interviews with key informants to examine the governance, actions, and potential impacts of the roundtables for sustainable beef, and identified opportunities and challenges for achieving greater sustainability impact. We found that the beef roundtables are in different stages of development and implementation and that they have diverse approaches based on their geographic contexts. However, they have universally adopted a model of sector-wide continuous improvement, in contrast to roundtables for other commodities, which have in many cases adopted formal certification programs. Activities by the roundtables for sustainable beef have variously included working towards definitions of sustainable beef; setting sustainability principles and criteria; and creating working groups to address specific aspects of sustainability (e.g., verification, deforestation). Our interviews identified opportunities to expand the roundtables’ roles, activities, and sustainability impacts. This study provides a benchmark of the roundtables’ efforts to date, and generates hypotheses and ideas for how they could evolve in the future.

We argue that an understanding of livestock farming as normative practice clarifies how sustainability is to be understood in livestock farming. The sustainability of livestock farming is first approached by investigating its identity. We argue that the economic aspect qualifies and the formative aspect founds the livestock farming practice. Observing the normativity related to these aspects will be the first task for the livestock farmer. In addition, we can distinguish conditioning norms applicable to the livestock farming practice which should be observed for competent performance of the practice. Failing to do justice to this normativity might affect the practice’s sustainability only in the long term—this is especially the case with conditioning norms. Motives to observe normativity have, therefore, the character of an ultimate conviction regarding the flourishing of the practice. Finally, the sustainability of the livestock farming practice crucially depends on the broader food system of which it is part.

Estuaries are among the most valuable aquatic systems by their services to human welfare. However, increasing human activities at the watershed along with the pressure of climate change are fostering the co-occurrence of multiple environmental drivers, and warn of potential negative impacts on estuaries resources. At present, no clear understanding of how coastal ecosystems will respond to the non-stationary effect of multiple drivers. Here we analysed the temporal interaction among multiple environmental drivers and their changing priority on shaping phytoplankton response in the Bahía Blanca Estuary, SW Atlantic Ocean. The interaction among environmental drivers and the number of significant direct and indirect effects on chlorophyll concentration increased over time in concurrence with enhanced anthropogenic stress, changing winter climate and wind patterns. Over the period 1978-1993, proximal variables such as nutrients, water temperature and salinity, showed a dominant effect on chlorophyll, whereas in more recent years (1993-2009) climate signals (SAM and ENSO) boosted indirect effects through its influence on precipitation, wind, water temperature and turbidity. Turbidity emerged as the dominant driver of chlorophyll while in recent years acted synergistically with the concentration of dissolved nitrogen. As a result, chlorophyll concentration showed a significant negative trend and a loss of seasonal peaks reflecting a pronounced reorganisation of the phytoplankton community. We stress the need to account for the changing priority of drivers to understand, and eventually forecast, biological responses under projected scenarios of global anthropogenic change.

Electricity spot market prices are increasingly affected by an expanding amount of renewables and a growing number of market participants. In an attempt to improve forecasting accuracy, this paper evaluates the importance of 62 predictor variables to forecast the the day-ahead electricity price. These variables describe the electricity price, load, generation and weather at different times in the Netherlands, Belgium and Germany. In this study we assess the performance of four machine learning models that forecast the electricity price. Next, we rank the variables according to their importance and identify to what extent different estimators and feature selection methods affect the performance of the forecasting models. We found that Random Forest regression is the best performing model regardless of the number of features selected and the feature selection method applied. Secondly, the performance of all models was not found to improve significantly after the selection of the top 15 ranked variables. Interestingly the top ranked variables differ significantly per selection method. Moreover, the feature selection methods based on Multi-variate Linear Regression and linear kernel Support Vector Machine were found to give the best performance for all models.

The hollow-fibre oxygenator is a key component of any extracorporeal circuit used to provide cardiopulmonary bypass (CPB) during open-heart surgery. Since the oxygenator is placed downstream of the pump, the energy losses over it have a direct impact on the quality of pulsatile pressure and flow waveforms. The objective of this study was to describe the effects of hydrodynamic characteristics of the oxygenator on energy transfer during pulsatile, normothermic CPB. Twenty-three adult patients scheduled for coronary bypass surgery were divided randomly into two groups, using either an oxygenator (Group 1) with a relatively high-resistance and low-compliance (2079 ± 148 dyn.s.cm-5 and 0.00348 ± 0.00071 ml.mmHg-1, respectively) or an oxygenator (Group 2) with a relatively low-resistance and high-compliance (884 ± 464 dyn.s.cm-5 and 0.01325 ± 0.00161 ml .mmHg-1, respectively). During perfusion, pre- and post-oxygenator pressures, radial artery pressure, and blood flow were recorded simultaneously. A 32% decline of mean pressure was observed in Group 1 and a 16% decline in Group 2 (p<0.0001). Another decrease by approximately 73% in mean pressure in the rest of the perfusion system was noted in both groups. The mean radial artery pressure did not differ between the groups (74 ± 6 mmHg in Group 1 and 73 ± 6 mmHg in Group 2, p=0.608). Although lower total energy transfer indices were noticed through the low-resistance oxygenator (Group 2), both oxygenators showed a decrease of the generated pump oscillatory energy of approximately 50%. Despite the differences in resistance and compliance of the hollow-fibre oxygenators used, both oxygenators cause a comparable loss of generated oscillatory energy. Exclusion of the oxygenator downstream of the pulsatile pump would improve energy transfer during CPB.