940 resultados para Concept of biological evolution


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The EU intends to increase the fraction of fuels from biogenic energy sources from 2% in 2005 to 8% in 2020. This means a minimum of 30 million TOE/a of fuels from biomass. This makes technical-scale generation of syngas from high-grade biomass, e.g. straw, hay, bark, or paper/cardboard waste, and the production of synthetic fuels by Fischer-Tropsch (FT) synthesis highly attractive. The BTL concept (Biomass to Liquids) of the Karlsruhe Research Center, labeled bioliq, focuses on this challenge by locally concentrating the biomass energy content by fast pyrolysis in a coke/oil slurry followed by slurry conversion to syngas in a central entrained flow gasifier at 1200C and pressures above 4MPa. FT synthesis generates intermediate products for synthetic fuels. To prevent the sensitive catalysts from being poisoned the syngas must be free of tar and particulates. Trace concentrations of H2S, COS, CS2, HCl, NH3, and HCN must be on the order of a few ppb. Moreover, maximum conversion efficiency will be achieved by cleaning the gas above the synthesis conditions. (T>350C, P>4MPa). The concept of an innovative dry HTHP syngas cleaning process is presented. Based on HT particle filtration and suitable sorption and catalysis processes for the relevant contaminants, an overall concept will be derived, which leads to a syngas quality required for FT synthesis in only two combined stages. Results of filtration experiments on a pilot scale are presented. The influence of temperature on the separation and conversion, respectively, of particulates and gaseous contaminants is discussed on the basis of experimental results obtained on a laboratory and pilot scale. Extensive studies of this concept are performed in a scientific network comprising the Karlsruhe Research Center and five universities; funding is provided by the Helmholtz Association of National Research Centers in Germany.

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South Asians have a higher risk of type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) than white Caucasians, for a given BMI. Premature biological ageing, assessed by reduction in telomere length (TL), may be mediated by factors resulting from altered metabolic profiles associated with obesity. We hypothesise that ethnicity and metabolic status represent detrimental factors contributing to premature biological ageing. Therefore we assessed TL in two South Asian, age and BMI-matched cohorts [T2DM (n = 142) versus non-T2DM (n = 76)] to determine the effects of BMI, gender, lipid and CVD profile on biological ageing. Genomic DNA was obtained from the UKADS cohort; biochemical and anthropometric data was collected and TL was measured by quantitative real-time PCR. Our findings indicated a gender-specific effect with reduced TL in T2DM men compared with non-T2DM men (P = 0.006). Additionally, in T2DM men, TL was inversely correlated with triglycerides and total cholesterol (r = -0.419, P <0.01; r = -0.443, P <0.01). In summary, TL was reduced amongst South Asian T2DM men and correlated with triglycerides and total cholesterol. This study highlights enhanced biological ageing among South Asian, T2DM men, which appears to be tracked by changes in lipids and BMI, suggesting that raised lipids and BMI may directly contribute to premature ageing.

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The relationship between the religious and political fields in the Orthodox Church is defined by the concept of symphonia which dates back to the Byzantine Empire. The concept suggests that the religious and political authorities should work together in a symphonic agreement towards achieving the material and spiritual welfare of the faithful. This article argues that an investigation of the theory of sign and symbol offers a better understanding of symphonia and, in particular, of its relationship with the nation-building process. From this perspective, by corroborating the data provided by the European Values Survey from 1990 to 2000 with this theory, this article demonstrates that the enlargement of the European Union represents the most significant challenge to symphonia, shifting its national focus to a supranational level. © 2011 Taylor & Francis.

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Market entry decisions are some of a firm's most important long-term strategic choices. Still, the international marketing literature has not yet fully incorporated the idea of relationship marketing in general, and the customer value concept in particular, as a basis for market entry decisions. This article presents some conceptual ideas about a customer value based market selection model. The metric International Added Customer Equity (IACE), a straightforward decision criterion derived from the customer equity concept is presented as an additional decision criterion for export market selection and ultimately market entry.

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A quasi-biotic model of knowledge evolution has been applied to manufacturing technology capability development which includes product design and development and manufacturing process/workflow improvement. The concepts of “knowledge genes” and “knowledge body” are introduced to explain the evolution of technological capability. It is shown that knowledge development within the enterprise happens as a result of interactions between an enterprise’s internal knowledge and that acquired from external sources catalysed by: (a) internal mechanisms, recources and incentives, and (b) actions and policies of external agencies. A matrix specifying factors contributing to knowledge development and types of manufacturing capabilities (product design, equipment development or use, and workflow) is developed to explain technological knowledge development. The case studies of Tianjin Pipe Corporation (TPCO) and Tianjin Tianduan Press Co. are presented to illustrate the application of the matrix.

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Biological soil crusts (BSCs) are formed by aggregates of soil particles and communities of microbial organisms and are common in all drylands. The role of BSCs on infiltration remains uncertain due to the lack of data on their role in affecting soil physical properties such as porosity and structure. Quantitative assessment of these properties is primarily hindered by the fragile nature of the crusts. Here we show how the use of a combination of non-destructive imaging X-ray microtomography (XMT) and Lattice Boltzmann method (LBM) enables quantification of key soil physical parameters and the modeling of water flow through BSCs samples from Kalahari Sands, Botswana. We quantify porosity and flow changes as a result of mechanical disturbance of such a fragile cyanobacteria-dominated crust. Results show significant variations in porosity between different types of crusts and how they affect the flow and that disturbance of a cyanobacteria-dominated crust results in the breakdown of larger pore spaces and reduces flow rates through the surface layer. We conclude that the XMT–LBM approach is well suited for study of fragile surface crust samples where physical and hydraulic properties cannot be easily quantified using conventional methods.

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The human mirror neuron system (MNS) has recently been a major topic of research in cognitive neuroscience. As a very basic reflection of the MNS, human observers are faster at imitating a biological as compared with a non-biological movement. However, it is unclear which cortical areas and their interactions (synchronization) are responsible for this behavioural advantage. We investigated the time course of long-range synchronization within cortical networks during an imitation task in 10 healthy participants by means of whole-head magnetoencephalography (MEG). Extending previous work, we conclude that left ventrolateral premotor, bilateral temporal and parietal areas mediate the observed behavioural advantage of biological movements in close interaction with the basal ganglia and other motor areas (cerebellum, sensorimotor cortex). Besides left ventrolateral premotor cortex, we identified the right temporal pole and the posterior parietal cortex as important junctions for the integration of information from different sources in imitation tasks that are controlled for movement (biological vs. non-biological) and that involve a certain amount of spatial orienting of attention. Finally, we also found the basal ganglia to participate at an early stage in the processing of biological movement, possibly by selecting suitable motor programs that match the stimulus.

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Soft ionization methods for the introduction of labile biomolecules into a mass spectrometer are of fundamental importance to biomolecular analysis. Previously, electrospray ionization (ESI) and matrix assisted laser desorption-ionization (MALDI) have been the main ionization methods used. Surface acoustic wave nebulization (SAWN) is a new technique that has been demonstrated to deposit less energy into ions upon ion formation and transfer for detection than other methods for sample introduction into a mass spectrometer (MS). Here we report the optimization and use of SAWN as a nebulization technique for the introduction of samples from a low flow of liquid, and the interfacing of SAWN with liquid chromatographic separation (LC) for the analysis of a protein digest. This demonstrates that SAWN can be a viable, low-energy alternative to ESI for the LC-MS analysis of proteomic samples.

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The presentation of cultural heritage is difficult comprehensive and constantly updated topic. Researchers often focus more on the different techniques to digitize artifacts of cultural heritage. This work focuses on the overall shape and structure of future multimedia application whose specificity is determined by the topic - Odrysian kingdom. Below is presented a concept for structure and content-based information available for individual kings from Odryssae dynasty. Special attention is paid to the presentation of preserved artifacts associated with the reign of specific rulers. The main concept of multimedia application dedicated to the Odrysian kingdom, it is to be used in teaching programs related to cultural heritage and history of antiquity in universities. The aim of designers is that it can be modified easy for use in museums also.

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2002 Mathematics Subject Classification: 62F35, 62F15.

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Az írás a kontraszelekció és az erkölcsi kockázat információ-gazdaságtani fogalmának politikatudományi alkalmazhatósága mellett érvel. Azt kívánja bemutatni, hogy a politikai piac szereplői közti információs aszimmetria mechanizmusainak éppúgy lehetnek súlyos negatív hatásai a demokratikus politikai rendszer működésére nézve, mint ahogy a gazdasági szereplők közti információs aszimmetria - Nobel-díjas közgazdászok érvei szerint - alááshatja a piaci verseny hatékonyságát. Az írás új megvilágításba helyezi a - már Platón óta ismert - politikai kontraszelekció jelenségét, továbbá részletesen foglalkozik az erkölcsi kockázat és a megbízó-megbízott relációk megjelenésével a politikában. Érinti tovább azoknak a mechanizmusoknak - a jelzésnek és a szűrésnek - a megjelenését a politikában, melyeket a közgazdászok az információs aszimmetria csökkentésére ajánlanak. / === / The paper argues in favour of employing in political science the economic concept of information asymmetry, seeking to show that the mechanisms of information asymmetry among the players on the political market may have negative effects on the operation of a democratic political system as information asymmetry among economic actors – according to arguments of Nobel prize-winning economists – has on the efficiency of market competition. The paper sheds new light on the phenomenon of negative political selection (known since Plato's time), and goes on to deal in detail with the appearance of moral risk and client/agent relations in politics. The author touches also on the appearance in politics of mechanisms – signals and filters – that economists suggest for reducing information asymmetry.

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Technology: Infliximab and comparator biological such as adalimumab, etanercept, golimumab. Conditions: Ankylosing spondylitis (AS) Issue: Infliximab is registered to be used in patients with AS. The aim of the Report is to evaluate the clinical efficacy and safety of infliximab and comparator biologicals for the treatment of adult AS. Methods: Systematic literature review and analysis as well as meta-analysis (direct and indirect comparison) of published randomised controlled clinical trials (RCT) were performed, all relevant health economics literature were identified ad analysed. Results: Clinical efficacy of biological therapies is based on good clinical evidences regarding to all clinical efficacy endpoints (ASAS20, ASAS40, ASAS 5/6, and BASDAI 50% response). Altogether, 22 trials are included in our meta-analysis, 12 infliximab, 3 adalimumab studies, 6 etanercept and 1 golimumab. Efficacy of biological treatments for the treatment of AS has been established by clinical scientific evidences, significant improvement at all outcomes considered was confirmed. According to the results of indirect comparison, there were no significant difference between biological treatments and placebo in terms of safety and tolerability endpoints. We found no significant difference between the clinical efficacy and safety of infliximab, adalimumab, etanercept and golimumab therapies. Cost-utility analysis of adalimumab and/or infliximab, etanercept and golimumab treatment for AS were performed in the UK, Canada, The Netherlands, Germany, Spain and France. There are no cost-utility studies from Eastern Central Europe. Implications for decision making: Efficacy of infliximab and comparator biologicals for the treatment of Ankylosing Spondylitis (AS) was proved by clinical evidence, significant improvement at all outcomes considered was confirmed. We found no significant differences in efficacy and safety of different biological treatments. Health economics results suggest that biological therapies are cost-effective alternatives for the treatment of AS in group of developed high income countries. There is a lack of health economics results in Central-Eastern European countries however these data are more and more required by governments and funders as part of the company economic dossiers.

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A cikk az alig több mint öt éve született referenciapont-elméletet mutatja be, ismerteti és értékeli a témában eddig megjelent cikkeket és a nagyobb horderejű munkaanyagokat. A referenciapont-elmélet arra a kérdésre keresi a választ, hogy mi a vállalat optimális mérete, és mikor érdemesebb a termelési kooperációt nem a vállalaton belül, a különböző egységek koordinációjával megoldani, hanem külső vállalatok segítségével, a piacon keresztül megvalósítani. A referenciapont-elmélet az azonos kérdések megválaszolására törekvő hiányos szerződések elméletét ért kritika hatására született meg, és saját, újonnan megfogalmazott feltételrendszerét számos ponton ötvözi a hiányos szerződések hipotéziseivel, ugyanakkor bizonyításai során felhasználja a standard közgazdasági irányzat több eszközét is. A cikk a friss eredmények bemutatása mellett megkísérli előre becsülni a referenciapont-elmélet várható jövőbeli fejlődési irányait is. ____ The concept of reference points was established slightly more than five years ago, and it deals with the same boundary of firm related questions as the incomplete contract theory. The present review shows the most important journals and research papers in this field. Reference point theory arose out of a criticism of some of the elements of incomplete contract theory. Reference point theory combines newly- formulated hypotheses with some of the assumptions of incomplete contracts. The theory also uses some of the proving tools of standard economics. The author’s study not only shows the main results of the reference point theory, but it also tries to predict some possible future developments within the theory.