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1.
Recent paleogeographic scenarios postulate the isolation of continental Africa during the Late Cretaceous. The absence of abelisaurid theropods from Upper Cretaceous African strata was offered as support of hypothesized African isolation with the acknowledgement that the paucity of African abelisaurids may be mostly an issue of sampling. Here we report on a shed theropod tooth from the Upper Cretaceous (Maastrichtian, ∼70 Ma) Duwi Formation of Egypt. The tooth was referred to the Malagasy abelisaurid “Megalosauruscrenatissimus (=Majungasaurus crenatissimus) in 1921. A discriminant function analysis was run to test for morphological congruence between the Egyptian tooth and the dentitions of 24 theropod taxa. The analysis correctly classified 96.6% of the teeth in the sample and assigned the tooth to Majungasaurus. As current paleogeographic reconstructions posit Madagascar had attained its current position relative to Africa before the Late Cretaceous, it is unlikely that the Egyptian tooth actually pertains to Majungasaurus. Nevertheless, its classification as an abelisaurid supports its referral to the clade. This tooth thus constitutes defensible evidence of an abelisaurid from the post-Cenomanian Cretaceous of mainland Africa. Combined with recent discoveries of abelisaurids in Niger and Morocco, the result indicates that Abelisauridae was a diverse group in Africa during the Cretaceous, existing in multiple places for at least ∼25 Ma and weakens support for hypotheses of an isolated Africa during the Late Cretaceous.Electronic Supplementary Material  Supplementary material is available for this article at
Joshua B. Smith (Corresponding author)Email: Phone: +1-314-9357033Fax: +1-314-9357361
Matthew C. LamannaEmail:
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2.
Approaches to semi-synthetic minimal cells: a review   总被引:1,自引:0,他引:1  
Following is a synthetic review on the minimal living cell, defined as an artificial or a semi-artificial cell having the minimal and sufficient number of components to be considered alive. We describe concepts and experiments based on these constructions, and we point out that an operational definition of minimal cell does not define a single species, but rather a broad family of interrelated cell-like structures. The relevance of these researches, considering that the minimal cell should also correspond to the early simple cell in the origin of life and early evolution, is also explained. In addition, we present detailed data in relation to minimal genome, with observations cited by several authors who agree on setting the theoretical full-fledged minimal genome to a figure between 200 and 300 genes. However, further theoretical assumptions may significantly reduce this number (i.e. by eliminating ribosomal proteins and by limiting DNA and RNA polymerases to only a few, less specific molecular species). Generally, the experimental approach to minimal cells consists in utilizing liposomes as cell models and in filling them with genes/enzymes corresponding to minimal cellular functions. To date, a few research groups have successfully induced the expression of single proteins, such as the green fluorescence protein, inside liposomes. Here, different approaches are described and compared. Present constructs are still rather far from the minimal cell, and experimental as well as theoretical difficulties opposing further reduction of complexity are discussed. While most of these minimal cell constructions may represent relatively poor imitations of a modern full-fledged cell, further studies will begin precisely from these constructs. In conclusion, we give a brief outline of the next possible steps on the road map to the minimal cell.
Pier Luigi Luisi (Corresponding author)Email:
Francesca FerriEmail:
Pasquale StanoEmail:
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3.
Almost two decades ago, Fleischmann and Pons reported excess enthalpy generation in the negatively polarized Pd/D-D2O system, which they attributed to nuclear reactions. In the months and years that followed, other manifestations of nuclear activities in this system were observed, viz. tritium and helium production and transmutation of elements. In this report, we present additional evidence, namely, the emission of highly energetic charged particles emitted from the Pd/D electrode when this system is placed in either an external electrostatic or magnetostatic field. The density of tracks registered by a CR-39 detector was found to be of a magnitude that provides undisputable evidence of their nuclear origin. The experiments were reproducible. A model based upon electron capture is proposed to explain the reaction products observed in the Pd/D-D2O system.
Pamela A. Mosier-BossEmail:
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4.
An important aspect of present global energy scenarios is the assumption that the amount of biomass that can be grown on the available area is so limited that a scenario based on biomass as the major source of energy should be unrealistic. We have been investigating the question whether a Biomass Scenario may be realistic. We found that the global energy demand projected by the International Energy Agency in the Reference Scenario for the year 2030 could be provided sustainably and economically primarily from lignocellulosic biomass grown on areas which have been degraded by human activities in historical times. Moreover, other renewable energies will contribute to the energy mix. There would be no competition with increasing food demand for existing arable land. Afforestation of degraded areas and investment for energy and fuel usage of the biomass are not more expensive than investment in energy infrastructure necessary up to 2030 assumed in the fossil energy based Reference Scenario, probably much cheaper considering the additional advantages such as stopping the increase of and even slowly reducing the CO2 content of the atmosphere, soil, and water conservation and desertification control. Most importantly, investment for a Biomass Scenario would be actually sustainable, in contrast to investment in energy-supply infrastructure of the Reference Scenario. Methods of afforestation of degraded areas, cultivation, and energetic usage of lignocellulosic biomass are available but have to be further improved. Afforestation can be started immediately, has an impact in some few years, and may be realized in some decades. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Jürgen O. MetzgerEmail:
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5.
Climate change combined with human activities poses significant risks to people’s livelihood especially in developing countries. Adaptation at the community level is of crucial importance in enabling them to respond to the direct and indirect effects of changes in climate. In a case study of fishing communities in Chilika lagoon, India, the focus is made on understanding climate change adaptation at the community level and scaling it up into the policy perspective through application of Sustainable Livelihood Approach. This article challenges the research and policy community to encourage the identification of locally negative constraints and positive strengths toward climate resilient communities in rural areas.
Rajib ShawEmail:
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6.
While greenhouse gas (GHG) emissions are projected to rise primarily in the developing countries, the potential for developing new GHG mitigation technologies exists primarily in the industrialized countries. It is thus important, not only for predictions about future emission paths but also for climate change mitigation policies, to understand how the international diffusion of such technologies takes place and how it affects the energy infrastructure and GHG emissions in developing countries. This paper provides an overview of the channels through which these technologies diffuse and focuses on the empirical evidence pertaining to the effects these technologies have on GHG emissions in developing countries.
Sonja PetersonEmail:
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7.
Over the past decade “bicellar” lipid mixtures composed of the long-chain dimyristoyl phosphatidylcholine (DMPC) and the short-chain dihexanoyl PC (DHPC) molecules have emerged as a powerful medium for studying membrane associated, biologically relevant macromolecules and assemblies. Depending on temperature, lipid concentration and composition these lipid mixtures can assume a variety of morphologies, some of them alignable in the presence of a magnetic field. This article will examine the biophysical studies that have elucidated the various morphologies assumed by these lipid mixtures, and their use in the biochemical studies of biomolecules.
John KatsarasEmail:
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8.
Molecular topology is an application of graph theory and statistics in fields like chemistry, biology, and pharmacology, in which the molecular structure matters. Its scope is the topological characterization of molecules by means of numerical invariants, called topological indices, which are the main ingredients of the molecular topological models. These are statistical models that are instrumental in the discovery of new applications of naturally occurring molecules, as well as in the design of synthetic molecules with specific chemical, biological, or pharmacological properties. In this review, we focus on pharmacology, which is a novel field of application of molecular topology. Besides summarizing some recent developments, we also seek to bring closer this interesting biomedical application of mathematics to an interdisciplinary readership.
Vincent M. VillarEmail:
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9.
A lower molar of a haramiyoid mammal is described from the Toutunhe Formation of Liuhuanggou near Urumqi in the southern Junggar Basin, Xinjiang, China. It is referred to Eleutherodon sp., otherwise exclusively known from the Upper Bathonian of England. It is the first record of the order Haramiyida from Asia and the first Mesozoic mammal described from the southern Junggar Basin. Apart from the English specimens of Eleutherodon and Staffia from the Upper Jurassic of East Africa, it is the geologically youngest haramiyoid known. It is the first vertebrate taxon from the Toutunhe Formation that is probably not endemic and lends some support to the dating of the Formation as late Middle Jurassic, probably Bathonian.
Michael W. MaischEmail:
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10.
A full account for carbon dioxide (CO2) and other greenhouse gas balance is presented for the Dutch forest and nature areas for 1990–2002 at a Tier 2.5 level. The paper outlines how complex guidelines can be turned into a practical system, appropriate for a small country, making use of the best knowledge and data available. The net total sink of all processes of the forest and other nature terrains balance is very stable through time around an average of 1.74 million tonnes of CO2 per year. The sink is to a large extent determined by the growth of forest remaining forest, and the harvest taking place in there. Newly added processes in this new National System are significant as well, but they compensate each other. The sources from deforestation and nitrous oxide (N2O) emissions (around 900 ktonne CO2) are for two thirds compensated by the sinks from afforestation, dead wood, soil C changes due to land use changes, and trees outside the forest. The land use changes between 1990 and 2000 showed that The Netherlands has an annual deforestation of 2504 ha (0.7% of the forest area) and an afforestation of 3124 ha. Deforestation led in total over the 13 years of 1990–2002 to an emission of 11.2 million tonne CO2 compensated by only 1.9 million tonne CO2 due to afforestation.
G. J. NabuursEmail:
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11.
Internal mitigation projects have recently been proposed as an additional flexibility mechanism, particularly in the context of the European Union. Their main objective is to engage sectors not included in the European Union emissions trading scheme (EU ETS) in cost-effective emissions reductions. However, in this paper it is argued that, when assessed in terms of dynamic efficiency, the instrument is likely to be, at best, irrelevant to induce the scale of systemic technological changes which are required to tackle the climate change problem and, at worst, detrimental for this task. Insights from the Evolutionary Economics of technological change complemented with political economy considerations are used to support this claim.
Pablo del RíoEmail:
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12.
Kirschbaum (Mitig Adapt Strat Glob Change 11:1151–1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary storage of carbon in the terrestrial biosphere “achieves effectively no climate-change mitigation”. His strongly worded statement begs for a response. This paper argues that Kirschbaum’s conclusion is an artifact of the specific perspective of his analysis and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change, a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better and longer is better, but even known temporary sinks have value.
Gregg Marland (Corresponding author)Email:
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13.
This paper addresses methodological issues in estimating carbon (C) sequestration potential, baseline determination, additionality and leakage in Khammam district, Andhra Pradesh, southern part of India. Technical potential for afforestation on cultivable wastelands, fallow, and marginal croplands was considered for Eucalyptus clonal plantations. Field studies for aboveground and belowground biomass, woody litter, and soil organic carbon for baseline and project scenarios were conducted to estimate the carbon sequestration potential. The baseline carbon stock was estimated to be 45.3 t C/ha, predominately in soils. The additional carbon sequestration potential under the project scenario for 30 years is estimated to be 12.8 t C/ha/year inclusive of harvest regimes and carbon emissions due to biomass burning and fertilizer application. Considering carbon storage in harvested wood, an additional 45% carbon benefit can be accounted. The project scenario has a higher benefit/cost ratio compared to the baseline scenario. The initial investment cost requirement, however, is high and lack of access to investment is a significant barrier for adoption of agroforestry in the district.
N. H. RavindranathEmail:
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14.
The paper presents a number of ideas on how climate change policy implementation in developing countries can be supported by alternative international cooperation mechanisms that are based on stakeholder interests and policy priorities including broader economic and social development issues. It includes a brief review of current development policies, technological research and promotion efforts, and climate change that demonstrates that mutual policy initiatives undertaken by governments and the private sector actually have major positive impacts on climate change without being initiated by this global policy concern. Furthermore a number of examples are given on how future development objectives in Brazil, China, and India jointly can support economic and social goals and global climate change concerns if these goals are taken into consideration and supported by international cooperative mechanisms. The paper proposes international cooperative mechanisms that can support the implementation of integrated development and climate change policies. The mechanisms include an international sustainable development (SD) and Climate Finance Mechanism (SDCFM), technology development and transition programmes, technology standards, and other measures.
Priyadarshi Shukla (Corresponding author)Email:
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15.
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of watershed development integrating into a suitable mitigation strategy for the country is assessed.
Preety M. BhandariEmail:
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16.
This paper studies the effects of adaptation and mitigation on the impacts of sea level rise. Without adaptation, the impact of sea level rise would be substantial, almost wiping out entire countries by 2100, although the globally aggregate effect is much smaller. Adaptation would reduce potential impacts by a factor 10–100. Adaptation would come at a minor cost compared to the damage avoided. As adaptation depends on socio-economic status, the rank order of most vulnerable countries is different than the rank order of most exposed countries. Because the momentum of sea level rise is so large, mitigation can reduce impacts only to a limited extent. Stabilising carbon dioxide concentrations at 550 ppm would cut impacts in 2100 by about 10%. However, the costs of emission reduction lower the avoided impacts by up to 25% (average 10%). This is partly due to the reduced availability of resources for adaptation, and partly due to the increased sensitivity to wetland loss by adaptation.
Richard S. J. TolEmail:
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17.
Community-based vulnerability assessment has often assumed that the local is the relevant level of adaptation to climate change. This paper suggests that not only do a number of levels from the international to the regional influence which adaptations can take place locally, but the governance network that is made up by actors on different levels may to a large extent be formed in responses to globalising factors, such as internationalisation of economies and the changing role of the state. The paper presents a study of adaptation in reindeer (Rangifier tarandus) herding, forestry and fishing communities in northern Norway, Sweden, and Finland, with a focus on assessing stakeholders’ own perceptions of environmental, socio-political and economic factors that affect them. In general, the paper illustrates the integration of non-subsistence economies into large and complex interactions where local adaptation is a result of the sum of stresses impacting individual entrepreneurs, and the potential they have to adapt their practices given governance (and their access to support) on different scales.
E. Carina H. KeskitaloEmail:
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18.
This article examines possibilities for linkage between the European Union Emissions Trading System (EU ETS) and Russia, with a view to enhancing cooperation on a broader scale than the project-based approaches that have been tested thus far. Three paths for possible EU-Russia linkage are presented by which the Russian Assigned Amount under the Kyoto Protocol can be greened in order to stimulate emissions trading: 1. Joint implementation—reductions earned via individual projects in Russia; 2. Greened allowances or green investment schemes; and 3. Linked cap-and-trade systems, in which a Russian domestic emissions trading system would link with the European Union Emissions Trading System. The authors conclude that the third option, emissions trading through linked domestic emissions trading systems, offers the best opportunities at the lowest transaction costs. The authors discuss useful innovative instruments like call options and slip level arrangements on government-to-government and business-to-business levels.
Annie PetsonkEmail:
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19.
This paper uses the likelihood of flooding along Brahmaputra and Ganges Rivers in India to explore the hypothesis that adaptation and mitigation can be viewed as complements rather than sustitutes. For futures where climate change will produce smooth, monotonic and manageable effects, adopting a mitigation strategy is shown to increase the ability of adaptation to reduce the likelihood of crossing critical threshold of tolerable climate. For futures where climate change will produce variable impacts overtime, though, it is possible that mitigation will make adaptation less productive for some time intervals. In cases of exaggerated climate change, adaptation may fail entirely regardless of how much mitigation is applied. Judging the degree of complementarity is therefore an empirical question because the relative efficacy of adaptation is site specific and path dependent. It follows that delibrations over climate policy should rely more on detailed analyses of how the distributions of possible impacts of climate might change over space and time.
Gary YoheEmail:
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20.
In the coming century, modern bioenergy crops have the potential to play a crucial role in the global energy mix, especially under policies to reduce carbon dioxide emissions as proposed by many in the international community. Previous studies have not fully addressed many of the dynamic interactions and effects of a policy-induced expansion of bioenergy crop production, particularly on crop yields and human food demand. This study combines an updated agriculture and land use (AgLU) model with a well-developed energy-economic model to provide an analysis of the effects of bioenergy crops on energy, agricultural and land use systems. The results indicate that carbon dioxide mitigation policies can stimulate a large production of bioenergy crops, dependent on the level of the policy. This production of bioenergy crops can lead to several impacts on the agriculture and land use system: decreases in forestland and unmanaged land, decreases in the average yield of food crops, increases in the prices of food crops, and decreases in the level of human demand of calories.
Steven J. Smith (Corresponding author)Email:
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