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991.
Siobhán M. Mattison Eric A. Smith Mary K. Shenk Ethan E. Cochrane 《Evolutionary anthropology》2016,25(4):184-199
Understanding how systems of political and economic inequality evolved from relatively egalitarian origins has long been a focus of anthropological inquiry. Many hypotheses have been suggested to link socio‐ecological features with the rise and spread of inequality, and empirical tests of these hypotheses in prehistoric and extant societies are increasing. In this review, we synthesize several streams of theory relevant to understanding the evolutionary origins, spread, and adaptive significance of inequality. We argue that while inequality may be produced by a variety of localized processes, its evolution is fundamentally dependent on the economic defensibility and transmissibility of wealth. Furthermore, these properties of wealth could become persistent drivers of inequality only following a shift to a more stable climate in the Holocene. We conclude by noting several key areas for future empirical research, emphasizing the need for more analyses of contemporary shifts toward institutionalized inequality as well as prehistoric cases. 相似文献
992.
Fuzzy rule‐based decision support system for evaluation of long‐established forest restoration projects 下载免费PDF全文
Although the importance of monitoring and evaluation of restoration actions is increasingly acknowledged, availability of accurate, quantitative monitoring data is very rare for most restoration areas, particularly for long‐established restoration projects. We propose using fuzzy rule‐based expert systems to evaluate the degree of success of restoration actions when available information on project results and impacts largely relies on expert‐based qualitative assessments and rough estimates of quantitative values. These systems use fuzzy logic to manage the uncertainty present in the data and to integrate qualitative and quantitative information. To illustrate and demonstrate the potential of fuzzy rule‐based systems for restoration evaluation, we applied this approach to seven forest restoration projects implemented in Spain between 1897 and 1952, using information compiled in the REACTION database on Mediterranean forest restoration projects. The information available includes both quantitative and expert‐based qualitative data, and covers a wide variety of indicators grouped into technical, structural, functional, and socioeconomic criteria. The fuzzy rule‐based system translates expert knowledge of restoration specialists and forest managers into a set of simple logic rules that integrate information on individual indicators into more general evaluation criteria. The rule‐based approach proposed here can be readily applicable to any kind of restoration project, provided that some information, even if vague and uncertain, is available for a variety of assessment indicators. The evaluation of long‐established forest restoration projects implemented in Spain revealed important asymmetries in the degree of restoration success between technical, structural, functional, and socioeconomic criteria. 相似文献
993.
《Bioorganic & medicinal chemistry》2016,24(18):4045-4055
The Oxa-Pictet–Spengler reaction of methyl 3-hydroxy-4-phenylbutanoate (8) was explored to obtain novel σ receptor ligands. 1-Acyl protected piperidone ketals 10 and 11 reacted with phenylethanol 8 to yield spirocyclic compounds. Aliphatic aldehyde acetals 19 provided 1,3-disubstituted 2-benzopyrans 20 with high cis-diastereoselectivity. The intramolecular Oxa-Pictet–Spengler reaction of 24 led to the tricyclic compound 25. The spirocyclic compounds 18 show high σ1 affinity (Ki 20–26 nM) and σ1/σ2 selectivity (>9-fold), when a large substituent (n-octyl, benzyl, phenylpropyl) is attached to the piperidine N-atom. Opening of the piperidine ring to yield aminoethyl (22, 23) or aminomethyl derivatives (21) resulted in reduced σ1 affinity and σ1/σ2 selectivity. 相似文献
994.
The present study was carried out to investigate the impact of climate change on land suitability for agricultural development in a sub-basin of Karkheh River Basin, Iran. For this, land suitability of the sub-basin was evaluated twice; once regardless of the climate change impact, and again by involving the impact of climate change. Simple Limitation Approach was used to evaluate the suitability of the sub-basin for cultivation of winter wheat. According to the results, around 22.57% (124121.16 ha) of the study area is suitable for cropping while the capability of 39.29% (216086.13 ha) of the sub-basin was evaluated to be poor/moderate for this purpose. In this research, in order to investigate the impact of climate change on farmlands, the changing trend of the four variables of maximum and minimum temperature, precipitation, and radiation were stimulated by the year 2039 using downscaled interpolation of IPCM general circulation model under three emission scenarios of A1B, A2, and B1. The stimulation was done by LARS-WG Software. The overlaying was done once more, but this time using the stimulated values. Comparing the current and stimulated land suitability maps revealed the fact that, in the most pessimistic future under A1B scenario, approximately 15.51% (85288.95 ha) of the study area will lose its capability for farming as a result of an increase of 1.3?C in temperature, and a decrease of 20.43% mm in total precipitation. The research finding emphasizes the risk of climate change on land health for farming purposes. 相似文献
995.
Solar Cells: Investigation of Charge Carrier Behavior in High Performance Ternary Blend Polymer Solar Cells (Adv. Energy Mater. 19/2016) 下载免费PDF全文
996.
Same school,different conduct: rates of multiple paternity vary within a mixed‐species breeding school of semi‐pelagic cichlid fish (Cyprichromis spp.) 下载免费PDF全文
Caleb Anderson Alexandra Werdenig Stephan Koblmüller Kristina M. Sefc 《Ecology and evolution》2016,6(1):37-45
Mating system variability is known to exist between and within species, often due to environmental influences. An open question is whether, vice versa, similar environmental conditions entail congruent mating behavior, for example in terms of multiple paternity, in species or populations sharing largely comparable breeding modes. This study employed microsatellite markers to investigate the incidence of multiple paternity in Cyprichromis coloratus and Cyprichromis leptosoma, two sympatric, closely related, mouthbrooding Lake Tanganyika cichlids with similar ecological and behavioral characteristics including the formation of open‐water schools. Mouthbrooding females of both species were collected from the same mixed‐species breeding school at the same time, minimizing environmental variation during courtship and mating. In C. coloratus, four of 12 broods had more than one sire, with a mean of 1.33 reconstructed sires per brood. C. leptosoma exhibited multiple paternity in 18 of 22 broods, with a mean of 2.59 or 2.86 reconstructed sires per brood according to the programs gerud and colony , respectively. In addition, two broods were found to contain offspring transplanted from another brood. There was no significant difference in brood size between species, but mean sire number did differ significantly. Hence, substantial similarity in reproductive behavior along with shared environmental conditions during courtship and spawning did not lead to equal rates of polyandry or sneaking in the two species. 相似文献
997.
998.
Techno‐economic analysis for incorporating a liquid–liquid extraction system to remove acetic acid into a proposed commercial scale biorefinery 下载免费PDF全文
Mitigating the effect of fermentation inhibitors in bioethanol plants can have a great positive impact on the economy of this industry. Liquid–liquid extraction (LLE) using ethyl acetate is able to remove fermentation inhibitors—chiefly, acetic acid—from an aqueous solution used to produce bioethanol. The fermentation broth resulting from LLE has higher performance for ethanol yield and its production rate. Previous techno‐economic analyses focused on second‐generation biofuel production did not address the impact of removing the fermentation inhibitors on the economic performance of the biorefinery. A comprehensive analysis of applying a separation system to mitigate the fermentation inhibition effect and to provide an analysis on the economic impact of removal of acetic acid from corn stover hydrolysate on the overall revenue of the biorefinery is necessary. This study examines the pros and cons associated with implementing LLE column along with the solvent recovery system into a commercial scale bioethanol plant. Using details from the NREL‐developed model of corn stover biorefinery, the capital costs associated with the equipment and the operating cost for the use of solvent were estimated and the results were compared with the profit gain due to higher ethanol production. Results indicate that the additional capital will add 1% to the total capital and manufacturing cost will increase by 5.9%. The benefit arises from the higher ethanol production rate and yield as a consequence of inhibitor extraction and results in a $0.35 per gallon reduction in the minimum ethanol selling price (MESP). © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:971–977, 2016 相似文献
999.
1000.
Lars Rytter 《Plant and Soil》1989,119(1):71-79
Development of below-ground biomass and biomass allocation were studied in two different stands of young grey alder stands
growing on a peat bog. Both stands were given the same fertilization and irrigation treatment. The roots were investigated
from 1) open plastic tubes enclosing the complete root systems in 1982, and 2) root cores 1984–86. Coarse roots (diameter>1
mm) were mainly found close to the trunk of the trees while fine roots (≤1 mm) were more evenly distributed in the stands.
Root nodules were intermediate in distribution. The root systems were shallow, with more than 90% of the biomass in the uppermost
9–10 cm of the soil, probably because of low oxygen availability in the peat soil. The biomass allocation to the above-ground
parts increased during the study period. 相似文献