74 research outputs found
Composition Dependent Instabilities in Mixtures With Many Components
Understanding the phase behavior of mixtures with many components is
important in many contexts, including as a key step toward a physics-based
description of intracellular compartmentalization. Here, we study the
instabilities of a mixture model where the second virial coefficients are taken
as random Gaussian variables. Using tools from free probability theory we
obtain the exact spinodal curve and the nature of instabilities for a mixture
with an arbitrary composition, thus lifting the assumption of uniform mixture
component densities pervading previous studies. We show that, by controlling
the volume fraction of only a few components, one can systematically change the
nature of the spinodal instability and achieve demixing for realistic scenarios
by a strong {\em composition imbalance amplification}. This results from a
non-trivial interplay of entropic effects due to non-uniform composition and
complexity in the interactions. Our approach allows for the inclusion of any
finite number of structured interactions, leading to a competition between
different forms of demixing as density is varied
Хромато-масс-спектрометрическое исследование состава продуктов взаимодействия 1,3,5-три-трет-бутилбензола с 2,4,6,8-тетрабром-2,4,6,8-тетраазабицикло[3.3.0]октан-3,7-дионом
Показано, что при взаимодействии 1,3,5-три-трет-бутилбензола с 2,4,6,8-тетрабром-2,4,6,8-тетраазабицикло[3.3.0]октан-3,7-дионом в уксусной и трифторуксусной кислотах наряду с образованием продуктов электрофильного бромирования происходят процессы, ipso-замещения трет-бутильных групп, диарилирования и гидроксилирования исходного субстрата
A Study on Estimating Method of Market Structure and Consumers Behavior
The ever-increasing growth in the 20th century which continued for a long time in the second half failed, and the industrial society of Japan has entered the time when tomorrow is obtuse. In order that variances among companies have spread, the meaning in which even the same industry gets to know the tendency of the whole industry has faded. It was over at the time that consists as a corporation if you enforce a similar thing to peer companies. This means the necessity that each company has original tactics and strategics has increased. Therefore, companies have to do development of new products by knowing both consumer needs and choice behavior. For this reason, companies need to collect data widely from consumers and to analyze them scientifically and statistically. Moreover, it is also important to study the theoretical methodology of marketing. In this paper, five models are utilized to understand the market structure and consumer behavior. 1 . Conjoint Analysis 2. Entropy Model and Herniter Model 3 . Conjoint Analysis and Herniter Model 4. Huff Model 5 . Huff Model and Herniter Model The above five models would contribute to new product development, estimate of future market structures and consumers behavior. By such kinds of knowledge, manufactures or companies could have good opportunities to market new products. Finally, the results derived from this thesis are summarized and future studies are described
Candida albicans Scavenges Host Zinc via Pra1 during Endothelial Invasion
The ability of pathogenic microorganisms to assimilate essential nutrients from their hosts is critical for pathogenesis. Here we report endothelial zinc sequestration by the major human fungal pathogen, Candida albicans. We hypothesised that, analogous to siderophore-mediated iron acquisition, C. albicans utilises an extracellular zinc scavenger for acquiring this essential metal. We postulated that such a “zincophore” system would consist of a secreted factor with zinc-binding properties, which can specifically reassociate with the fungal cell surface. In silico analysis of the C. albicans secretome for proteins with zinc binding motifs identified the pH-regulated antigen 1 (Pra1). Three-dimensional modelling of Pra1 indicated the presence of at least two zinc coordination sites. Indeed, recombinantly expressed Pra1 exhibited zinc binding properties in vitro. Deletion of PRA1 in C. albicans prevented fungal sequestration and utilisation of host zinc, and specifically blocked host cell damage in the absence of exogenous zinc. Phylogenetic analysis revealed that PRA1 arose in an ancient fungal lineage and developed synteny with ZRT1 (encoding a zinc transporter) before divergence of the Ascomycota and Basidiomycota. Structural modelling indicated physical interaction between Pra1 and Zrt1 and we confirmed this experimentally by demonstrating that Zrt1 was essential for binding of soluble Pra1 to the cell surface of C. albicans. Therefore, we have identified a novel metal acquisition system consisting of a secreted zinc scavenger (“zincophore”), which reassociates with the fungal cell. Furthermore, functional similarities with phylogenetically unrelated prokaryotic systems indicate that syntenic zinc acquisition loci have been independently selected during evolution
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