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While the member states of the Gulf Cooperation Council have economically and politically been dominated by the exploitation of fossil fuels, recent years have seen an increasing adoption of renewable energy technologies, the reasons of which are not yet sufficiently understood. This paper argues that the recent adoption of renewable energy technologies in the Gulf and its striking variation can be explained by theories of policy transfer. In addition, we find some support for the alternative hypothesis of endogenous policy development regarding political leadership. Yet there is no support for the alternative hypothesis of a strong direct influence of the international climate regime. Furthermore, the policy transfer hypothesis and political leadership stand as coexisting influences on renewable energy adoption, rather than competing ones. Based on an extensive study of primary and secondary sources, local reports and country analyses of international organizations, and personal interviews with key experts, this paper lays out in detail how transfers of renewable energy policies take place in the Gulf; their drivers; and their impacts. We also discuss the factors that lead countries to lag behind, which can be helpful for prospective research on a more extensive utilization of renewable energy in the region and beyond.

AbstractThe assignment of the crystallographic axes for the hole momentum‐space wave function maps shown in Fig. 2 of Reuter et al., phys. stat. sol. (b) 243, 3942 (2006) has been corrected. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

We present a comparison of the energy transfer between carotenoid dark states and chlorophylls for the minor complexes CP24 and CP29. To elucidate the potential involvement of certain carotenoid-chlorophyll coupling sites in fluorescence quenching of distinct complexes, varying carotenoid compositions and mutants lacking chlorophylls at specific binding sites were examined. Energy transfers between carotenoid dark states and chlorophylls were compared using the coupling parameter, [Formula: see text], which is calculated from the chlorophyll fluorescence observed after preferential carotenoid two-photon excitation. In CP24, artificial reconstitution with zeaxanthin leads to a significant reduction in the chlorophyll fluorescence quantum yield, [Formula: see text], and a considerable increase in [Formula: see text]. Similar effects of zeaxanthin were also observed in certain samples of CP29. In CP29, also the replacement of violaxanthin by the sole presence of lutein results in a significant quenching and increased [Formula: see text]. In contrast, the replacement of violaxanthin by lutein in CP24 is not significantly increasing [Formula: see text]. In general, these findings provide evidence that modification of the electronic coupling between carotenoid dark states and chlorophylls by changing carotenoids at distinct sites can significantly influence the quenching of these minor proteins, particularly when zeaxanthin or lutein is used. The absence of Chl612 in CP24 and of Chl612 or Chl603 in CP29 has a considerably smaller effect on [Formula: see text] and [Formula: see text] than the influence of some carotenoids reported above. However, in CP29 our results indicate slightly dequenching and decreased [Formula: see text] when these chlorophylls are absent. This might indicate that both, Chl612 and Chl603 are involved in carotenoid-dependent quenching in isolated CP29.

We determine which urban form generates minimal global and local emissions. To this end, we develop a spatial accounting model of a circular city consisting of six zones. Activities comprise low and high density housing, offices and industry. Spatial interactions among activities give rise to freight and passenger transport. We assess global emissions of greenhouse gases due to the direct and indirect use of coal, oil and gas by economic activities and transport. In addition, we calculate local emissions which are zone-specific. Distribution and health effects of such emissions are also taken into account. The model analyses each urban form for various scenarios of distinct shares of electric vehicles in transport and of renewable energy in electricity production. Numerical exercises allow establishing a relationship between optimal urban form and shares of electric vehicles and renewable energy. We also derive transition paths to the most desirable urban form considering minimal transition effort. This may help urban planners to design a feasible time strategy for improving urban form in terms of emissions.

Abstract Harmful SO2 largely originates from coal and oil combustions, but in some areas the biomass burning contribution could not be ignored. Here, we evaluated SO2 emissions from biomass burning (BB-SO2) with largely focusing on regional difference and temporal trends in the relative contributions of biomass burning from different sectors. Globally, the biomass burning emitted 4.26 (3.20–6.20) Tg SO2 in 2014, contributing 4.0% of the total SO2 emissions stemming from anthropogenic sources and natural open fires. But in some African and South Asian countries, biomass burning was a major source of SO2 with the contribution as high as 80–90%. Regarding sector contributions of biomass SO2, open fires contributed nearly half, followed by the residential sector (~29%) on the global scale, however, substantially different profiles were revealed across countries. Residential sector is the largest anthropogenic BB-SO2 source in the developing countries, while in the developed countries, industry and energy production were the two main anthropogenic BB-SO2sources. From 1960 to 2014, biomass SO2 emission, either the absolute amount or the relative contribution to the total, increased in the U.S. and Europe, and the contributions were over 20% in some countries. The biomass burning SO2 emission showed an increasing trend in India and a unimodal change in China, while a decreasing trend in the relative contributions were revealed in these two largest developing countries, which were 2.7% and 0.8%, respectively in 2014. With unignorable biomass burning contribution to SO2, as well as other hazardous air pollutants, in some regions, it is suggested that in assessing climate and health impacts of promoted biomass utilization when phasing out of fossil fuels, multiple components should be co-evaluated.

Abstract Fitting an equivalent current dipole (ECD) to magnetoencephalography (MEG) data is a widely used method for analyzing MEG data, especially in clinical applications. However, as is well known, the iterative fitting algorithms routinely employed can converge on a local minima far from the best fit. While a host of fitting algorithms have been proposed to remedy this problem, the simple exhaustive search optimization algorithm has not been considered in the literature — possibly because it is assumed to be too slow for routine use. Taking advantage of the speed of modern computers, it is demonstrated that using exhaustive search to fit the parameters of a single ECD to 151 MEG channels yields both robust and reproducible fits within reasonable computation times. On a high end personal computer, with a 2 mm grid spacing over the head, exhaustive search can fit 450 ECD's per hour with only an additional 5 min spent on calculating the lead fields. As the algorithm is fully automatic, it is very useful when the goal is to detect ECD's in a large dataset. Also, an interpreter can be provided with parameters from the ECD that fits for all latencies after stimulus, allowing a more informed decision of which latency to use for further analysis.

The continuous production of biohythane (mixture of biohydrogen and methane) from food waste using an integrated system of a continuously stirred tank reactor (CSTR) and anaerobic fixed bed reactor (AFBR) was carried out in this study. The system performance was evaluated for an operation period of 200days, by stepwise shortening the hydraulic retention time (HRT). An increasing trend of biohydrogen in the CSTR and methane production rate in the AFBR was observed regardless of the HRT shortening. The highest biohydrogen yield in the CSTR and methane yield in the AFBR were 115.2 (±5.3)L H2/kgVSadded and 334.7 (±18.6)L CH4/kgCODadded, respectively. The AFBR presented a stable operation and excellent performance, indicated by the increased methane production rate at each shortened HRT. Besides, recirculation of the AFBR effluent to the CSTR was effective in providing alkalinity, maintaining the pH in optimal ranges (5.0-5.3) for the hydrogen producing bacteria.

The Cretaceous-Palaeogene (K-Pg) boundary mass extinction event is related to major global environmental changes resulting from a large extraterrestrial impact. Organic-walled cyst-producing marine dinoflagellates (dinocysts) survived the K-Pg mass-extinction relatively unscathed, making them ideally suited for reconstructing these environmental changes. So far, one of the best dinocyst records available is from the K-Pg boundary Global Stratotype Section and Point (GSSP) at El Kef (NW Tunisia). There, the dinocyst record shows major fluctuations across the boundary, likely reflecting strong responses to environmental changes. These fluctuations have so far not been confirmed by other studies. Therefore, in this study we performed a high-resolution marine palynological study on a closely spaced sample set from the Elles section, some 75km south of El Kef, in order to generate a palaeoenvironmental and palaeoclimatic record across the K-Pg boundary to allow verification and refinement of earlier reported environmental changes. To better constrain the reconstructions based on qualitative biotic proxies we employed the quantitative sea surface temperature proxy TEX86. Unfortunately, the TEX86 proxy record of the studied section is compromised because of post-depositional oxidation. However, the diverse dinocyst assemblages at Elles show strong fluctuations similar to the El Kef record, therefore confirming the earlier recorded signals, showing rapid, regionally consistent changes. These records imply that the latest Cretaceous was characterized by a gradual cooling trend and the onset of relative sea level fall. Within the immediate post-extinction interval, in the first thousands of years after the impact, dinocyst assemblages reveal multiple incursions of higher-latitude dinocyst species implying repeated pulses of cooling. These results signify that the earliest Danian climatic and environmental conditions were relatively unstable across the Tunisian shelf.