943 resultados para Photius I, Saint, Patriarch of Constantinople, ca. 820-ca. 891.
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Az elmúlt évtizedekben a gazdálkodástudomány kitüntetett figyelemmel kísért két – mind a makrogazdaság, mind az egyes vállalatok működésének sikere szempontjából meghatározó fontosságú – jelenséget, egyrészt a szolgáltatásoknak a hagyományos termeléssel szembeni egyre erőteljesebb térnyerését, másrészt a fogyasztói érték teremtése szempontjából növekvő jelentőségű ellátási láncoknak, illetve azok menedzsmentjének kérdéskörét. Ugyanakkor igen kevés elemzés, de kevés leíró jellegű munka is született a két jelenséget és menedzsmentproblémát összekapcsoló területről, azaz a szolgáltatások ellátási láncáról, ezen ellátási láncok kezelésének speciális problémáiról. A szerzők cikkükben a szolgáltatások ellátási láncának és menedzsmentjének jellegzetességeit, a klasszikus terméket előállító ellátási láncokhoz viszonyított sajátosságait foglalják össze a nemzetközi szakirodalom alapján. Ennek során bemutatják, hogy az ún. tiszta szolgáltatások széles körben ismert jellemzői hatással vannak a szolgáltatások előállítását és értékesítését végző ellátási láncok működésére is. Ezek a hatások és specialitások megjelennek az ellátásilánc-menedzsment irodalmában kiemelten tárgyalt mindhárom problémakörben, rányomják tehát bélyegüket mind az ellátási lánc felépítésére, mind az ellátási láncban együttműködő partnerek kapcsolatának kezelésére és végül, de nem utolsósorban az ellátásilánc-menedzsment folyamatok kezelésére. _________ In the last decades scholars have paid a lot of attention to both service operation and supply chain management. There is still limited research on the overlapping field of theses two management areas, on service supply chain specialties. This article gives a structured overview on the latest research results on this topic. Doing so the paper would like to draw attention of the Hungarian researchers to this field and facilitate these empirical researches. As described in the paper traditional service specialties (intangibility, perishability, inseparability, heterogeneity and the importance of human capital) create special management problems concerning (i) the structure of these supply chains, (ii) their relationship management and (iii) the management of supply chain processes.
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Cardiac troponin I (cTnI) is one of the most useful serum marker test for the determination of myocardial infarction (MI). The first commercial assay of cTnI was released for medical use in the United States and Europe in 1995. It is useful in determining if the source of chest pains, whose etiology may be unknown, is cardiac related. Cardiac TnI is released into the bloodstream following myocardial necrosis (cardiac cell death) as a result of an infarct (heart attack). In this research project the utility of cardiac troponin I as a potential marker for the determination of time of death is investigated. The approach of this research is not to investigate cTnI degradation in serum/plasma, but to investigate the proteolytic breakdown of this protein in heart tissue postmortem. If our hypothesis is correct, cTnI might show a distinctive temporal degradation profile after death. This temporal profile may have potential as a time of death marker in forensic medicine. The field of time of death markers has lagged behind the great advances in technology since the late 1850's. Today medical examiners are using rudimentary time of death markers that offer limited reliability in the medico-legal arena. Cardiac TnI must be stabilized in order to avoid further degradation by proteases in the extraction process. Chemically derivatized magnetic microparticles were covalently linked to anti-cTnI monoclonal antibodies. A charge capture approach was also used to eliminate the antibody from the magnetic microparticles given the negative charge on the microparticles. The magnetic microparticles were used to extract cTnI from heart tissue homogenate for further bio-analysis. Cardiac TnI was eluted from the beads with a buffer and analyzed. This technique exploits banding pattern on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by a western blot transfer to polyvinylidene fluoride (PVDF) paper for probing with anti-cTnI monoclonal antibodies. Bovine hearts were used as a model to establish the relationship of time of death and concentration/band-pattern given its homology to human cardiac TnI. The final concept feasibility was tested with human heart samples from cadavers with known time of death. ^
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The purpose of this study was to explore postmodern identity in the work of Chuck Palahniuk. The characters within Palahniuk's text Invisible Monsters realize the manner in which identity is a construct, and their response is to oppose and redefine it. In my research, I looked at how postmodern identity is defined by some of the leading critical thinkers in the field, and then I applied their thought to Palahniuk's characters. I showed how these characters come to understand the process by which society defines them, and with that realization, they oppose its totalizing definitions. The characters deconstruct the natural attitudes society has towards identity, and they reveal that it is in some way possible to create a unique identity that is not easily definable by the ruling discourse. I concluded that his attention to identity highlights Palahniuk's concern for the place, identity, and influence of his generation.
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Past river run-off is an important measure for the continental hydrological cycle and the as-sessment of freshwater input into the ocean. However, paleosalinity reconstructions applying different proxies in parallel often show offsets between the respective methods. Here, we compare the established foraminiferal Ba/Ca and d18OWATER salinity proxies for their capability to record the highly seasonal Orinoco freshwater plume in the eastern Caribbean. For this purpose we obtained a data set comprising Ba/Ca and d18OWATER determined on multiple spe-cies of planktonic foraminifera from core tops distributed around the Orinoco river mouth. Our findings indicate that interpretations based on either proxy could lead to different conclu-sions. In particular, Ba/Ca and d18OWATER diverge in their spatial distribution due to different governing factors. Apparently, the Orinoco freshwater plume is best tracked by Ba/Ca ratios of G. ruber (pink and sensu lato morphotypes), while d18OWATER based on the same species is more related to the local precipitation-evaporation balance overprinting the riverine freshwater contribution. Other shallow dwelling species (G. sacculifer, O. universa) show a muted response to the freshwater discharge, most likely due to their ecological and habitat prefer-ences. Extremely high Ba/Ca ratios recorded by G. ruber are attributed to Ba2+-desorption from suspended matter derived from the Orinoco. Samples taken most proximal to the freshwater source do not show pronounced Ba/Ca or d18OWATER anomalies. Here, the suspension loaded freshwater lid developing during maximum discharge suppresses foraminiferal populations. Both proxies are therefore biased towards dry season conditions at these sites, when surface salinity is only minimally reduced.
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Humanity is shaped by its relationships with microbes. From bacterial infections to the production of biofuels, industry and health often hinge on our control of microbial populations. Understanding the physiological and genetic basis of their behaviors is therefore of the highest importance. To this end I have investigated the genetic basis of plastic adhesion in Saccharomyces cerevisiae, the mechanistic and evolutionary dynamics of mixed species biofilms with Escherichia coli and S. cerevisiae, and the induction of filamentation in E. coli. Using a bulk segregant analysis on experimentally evolved populations, I detected 28 genes that are likely to mediate plastic adhesion in S. cerevisiae. With a variety of imaging and culture manipulation techniques, I found that particular strains of E. coli are capable of inducing flocculation and macroscopic biofilm formation via coaggregation with yeast. I also employed experimental evolution and microbial demography techniques to find that selection for mixed species biofilm association leads to lower fecundity in S. cerevisiae. Using culture manipulation and imaging techniques, I also found that E. coli are capable of inducing a filamentous phenotype with a secreted signal that has many of the qualities of a quorum sensing molecule.
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The occurrence of hand grindstones at the Cogotas I archaeological sites is considered to be a common feature. Given that a distant-provenance raw material is frequently involved, determination of its source is a basic factor in the search for a better understanding of resource management and for any Political Economy approach. To progress in these directions an overall study should be planned, using selected grindstones with a view to covering diverse sub-zones of the Cogotas I dispersal area, especially because of its considerable distance from the granite basement source. Such a study may today includes diverse analytical procedures combining successive geographic, petrographic, mineralogical and geochemical criteria. To check the plausibility of the proposed methodology, a preliminary test has been carried out on two granite grindstones, obtained at the archaeological excavation at the Castronuño (Valladolid) Cogotian site, which is fifty km away from an inferred source area that was presumably located at Peñausende (Zamora). The result obtained validates the proposed operational process, yielding a generalizable knowledge to other similar situations.
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[Excerpt] Overall, this book is an important contribution to the organizational studies literature. The Big-Three Model and the case studies supporting it provide new insights regarding the ways in which changes affect individuals and organizations. Further theoretical developments should build on this framework, and incorporate elements of this model into more detailed schemas of change. The authors have exposed many new research questions and provided many lessons for practitioners. I look forward to additional work from them.
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This essay focuses on the alienation experienced by Rusty-James in S.E. Hinton’s Rumble Fish (1975). It more specifically centers on the causes of his alienation and how the alienation is illustrated in the novel. The analysis shows that the alienation Rusty-James experiences is caused partly by socioeconomic factors; for example his lack of hope for the future is closely connected to the fact that he belongs to a low socioeconomic class. In addition, there are also psychological factors, for example a childhood trauma. The alienation and its causes are mainly illustrated through the symbolism of the featured Siamese fighting fish and how Rusty-James’ relationships are depicted.
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Carbonic anhydrases are enzymes that are ubiquitously found in all organisms that are engaged in catalyzing the hydration of carbon dioxide to form bicarbonate and proton and vice versa. They are crucial in the process of respiration, bone resorption, pH regulation, ion transport, and photosynthesis in plants. Out of the five classes of carbonic anhydrase α, β, γ, δ, ζ this study focused in the α carbonic anhydrases. This class of CAs constitute of 16 subfamilies in mammals that include 3 non-active enzymes known as Carbonic Anhydrase Related Proteins. The inactiveness of these enzymes is due to the loss of one or more Histidine residues in the active site. This thesis was conducted based on the aim of studying evolutionary analysis of carbonic anhydrase sequences from organisms spanning from the Cambrian age. It was carried out in two phases. The first phase was the sequence collection, which involved many biological sequence databases as a source. The scope of this segment included sequence alignments and analysis of the sequence manually and in an automated form incorporating few analysis tools. The second Phase was phylogenetic analysis and exploring the subcellular location of the proteins, which was key for the evolutionary analysis. Through the medium of the methods conducted with respect to the phases mentioned above, it was possible to accomplish the desired result. Certain thought-provoking sequences were come across and analyzed thoroughly. Whereas, Phylogenetics showed interesting results to bolster previous findings and new findings as well which lay bedrock for future intensified studies.
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The mitochondrial NADH dehydrogenase complex (complex I) is of particular importance for the respiratory chain in mitochondria. It is the major electron entry site for the mitochondrial electron transport chain (mETC) and therefore of great significance for mitochondrial ATP generation. We recently described an Arabidopsis thaliana double-mutant lacking the genes encoding the carbonic anhydrases CA1 and CA2, which both form part of a plant-specific 'carbonic anhydrase domain' of mitochondrial complex I. The mutant lacks complex I completely. Here we report extended analyses for systematically characterizing the proteome of the ca1ca2 mutant. Using various proteomic tools, we show that lack of complex I causes reorganization of the cellular respiration system. Reduced electron entry into the respiratory chain at the first segment of the mETC leads to induction of complexes II and IV as well as alternative oxidase. Increased electron entry at later segments of the mETC requires an increase in oxidation of organic substrates. This is reflected by higher abundance of proteins involved in glycolysis, the tricarboxylic acid cycle and branched-chain amino acid catabolism. Proteins involved in the light reaction of photosynthesis, the Calvin cycle, tetrapyrrole biosynthesis, and photorespiration are clearly reduced, contributing to the significant delay in growth and development of the double-mutant. Finally, enzymes involved in defense against reactive oxygen species and stress symptoms are much induced. These together with previously reported insights into the function of plant complex I, which were obtained by analysing other complex I mutants, are integrated in order to comprehensively describe 'life without complex I'.
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The chemical factors (inorganic nitrogen, phosphate, silicic acid) that potentially or actually control primary production were determined for the Bay of Brest, France, a macrotidal ecosystem submitted to high-nitrate-loaded freshwater inputs (winter nitrate freshwater concentrations >700 mu M, Si:N molar ratio as low as 0.2, i.e. among the lowest ever published). Intensive data collection and observations were carried out from February 1993 to March 1994 to determine the variations of physical [salinity, temperature, photosynthetically active radiation (PAR), freshwater discharges] and chemical (oxygen and nutrients) parameters and their impacts on the phytoplankton cycle (fluorescence, pigments, primary production). With insufficient PAR the winter stocks of nutrients were almost nonutilized and the nitrate excess was exported to the adjacent ocean, due to rapid tidal exchange. By early April, a diatom-dominated spring bloom developed (chlorophyll a maximum = 7.7 mu g l(-1); primary production maximum = 2.34 g C m(-2) d(-1)) under high initial nutrient concentrations. Silicic acid was rapidly exhausted over the whole water column; it is inferred to be the primary limiting factor responsible for the collapse of the spring bloom by mid-May. Successive phytoplankton developments characterized the period of secondary blooms during summer and fall (successive surface chlorophyll a maxima = 3.5, 1.6, 1.8 and 1.0 mu g l(-1); primary production = 1.24, 1.18 and 0.35 g C m(-2) d(-1)). Those secondary blooms developed under lower nutrient concentrations, mostly originating from nutrient recycling. Until August, Si and P most likely limited primary production, whereas the last stage of the productive period in September seemed to be N limited instead, this being a period of total nitrate depletion in almost the whole water column. Si limitation of spring blooms has become a common feature in coastal ecosystems that receive freshwater inputs with Si:N molar ratios <1. The peculiarity of Si Limitation in the Bay of Brest is its extension through the summer period.
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The dynamics of intracellular Ca⁺ is driven by random events called Ca⁺ puffs, in which Ca⁺ is liberated from intracellular stores. We show that the emergence of Ca⁺ puffs can be mapped to an escape process. The mean first passage times that correspond to the stochastic fraction of puff periods are computed from a novel master equation and two Fokker-Planck equations. Our results demonstrate that the mathematical modeling of Ca⁺ puffs has to account for the discrete character of the Ca⁺ release sites and does not permit a continuous description of the number of open channels.
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We present a bidomain threshold model of intracellular calcium (Ca⁺) dynamics in which, as suggested by recent experiments, the cytosolic threshold for Ca⁺ liberation is modulated by the Ca⁺ concentration in the releasing compartment. We explicitly construct stationary fronts and determine their stability using an Evans function approach. Our results show that a biologically motivated choice of a dynamic threshold, as opposed to a constant threshold, can pin stationary fronts that would otherwise be unstable. This illustrates a novel mechanism to stabilise pinned interfaces in continuous excitable systems. Our framework also allows us to compute travelling pulse solutions in closed form and systematically probe the wave speed as a function of physiologically important parameters. We find that the existence of travelling wave solutions depends on the time scale of the threshold dynamics, and that facilitating release by lowering the cytosolic threshold increases the wave speed. The construction of the Evans function for a travelling pulse shows that of the co-existing fast and slow solutions the slow one is always unstable.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)