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The first model

In 1981, the Journal of Theoretical Biology published The ribotype theory on the origin of life , a paper which proposed two novel ideas  [Pg.248]

The origin-of-life scenario was instrumental for the new theory of the cell, because it led to the the conclusion that the ribotype had an evolutionary priority over genotype and phenotype. More precisely, the scenario described a precellular ribotype world (not to be confused with the RNA world) where some ribosoids could act as templates (ribogenotype), others as enzymes (ribophenotype), and others as polymerising ribosoids (ribotype) that were responsible for the growth and the quasi-replication of the ribonucleoprotein systems. [Pg.248]

The ribotype cannot be given up because there is no DNA and no protein that can do the job of protein synthesis. Proteins and DNAs are two independent worlds, and only an organic code can build a bridge between them. The genetic code is that bridge, and that code [Pg.248]


There are two approaches to explain physical mechanism of the phenomenon. The first model is based on the existence of the difference between the saturated vapor pressures above two menisci in dead-end capillary. It results in the evaporation of a liquid from the meniscus of smaller curvature ( classical capillary imbibition) and the condensation of its vapor upon the meniscus of larger curvature originally existed due to capillary condensation. [Pg.616]

One of the first models to describe electronic states in a periodic potential was the Kronig-Penney model [1]. This model is commonly used to illustrate the fundamental features of Bloch s theorem and solutions of the Schrodinger... [Pg.101]

From among the many reaction classification schemes, only a few are mentioned here. The first model concentrates initially on the atoms of the reaction center and the next approach looks first at the bonds involved in the reaction center. These are followed by systems that have actually been implemented, and whose performance is demonstrated. [Pg.183]

The modeling of SMB can be addressed by simulating the system directly, taking into account its intermittent behavior, or by representing its operation in terms of a true countercurrent system. The first model represents the real SMB and considers the periodic switch of the injection and collection points. The second is developed assuming the equivalence with the TMB, where solid and fluid flow in opposite directions. [Pg.222]

The first modeling software which allowed for the optimization of nonlinear separations by SMB was presented in the early 1990s [46]. Today, numerous publications from academia allows one to have a better understanding of the SMB system [47-51]. Industry now has the practical tools for modeling SMB for quick and efficient process optimization [41, 52]. [Pg.258]

The first instantaneous water heaters which started appearing in the 1890s when gas or liquid fuels started becoming available, were un-pressurized. The first models had no automatic controls and vei"y limited safety features. Some early models were more efficient than standard modern gas-fired water heaters. [Pg.1214]

Indeed, the multi-layered model, applied to fiber reinforced composites, presented a basic inconsistency, as it appeared in previous publications17). This was its incompatibility with the assumption that the boundary layer, constituting the mesophase between inclusions and matrix, should extent to a thickness well defined by thermodynamic measurements, yielding jumps in the heat capacity values at the glass-transition temperature region of the composites. By leaving this layer in the first models to extent freely and tend, in an asymptotic manner, to its limiting value of Em, it was allowed to the mesophase layer to extend several times further, than the peel anticipated from thermodynamic measurements, fact which does not happen in its new versions. [Pg.174]

A series of models were introduced in this study, which take care of the existence of this boundary layer. The first model, the so-called three-layer, or N-layer model, introduces the mesophase layer as an extra pseudophase, and calculates the thickness of this layer in particulates and fiber composites by applying the self-consistent technique and the boundary- and equilibrium-conditions between phases, when the respective representative volume element of the composite is submitted to a thermal potential, concretized by an increase AT of the temperature of the model. [Pg.185]

The second important point is common for all charge-transfer reactions. The proton is a charged particle, and as such, interacts strongly with solvent polarization. The first model taking into account botfi tfiese points was proposed by Dogonadze et al. (1967). [Pg.658]

The TEM data have been used to simulate, in the frame of the Mie theory and Maxwell-Garnett effective medium approximation [15], the optical absorption spectra of the sample implanted with 5 x lO Au /cm. The results are reported in Figure 8(c). In the first model used to describe... [Pg.277]

RICEWQ was the first model developed for agrochemical runoff from paddy fields, incorporating aircraft application, dissipation by drift, adhesion on leaf surfaces, and dissipation from the leaf surface in addition to the processes affecting degradation and transport in sediment and paddy water. An important parameter, desorption from sediment to paddy water, is not considered, although this is not as important as other parameters in paddy fields such as sedimentation rate, behavior of SS, etc. [Pg.906]

The first model of membrane electroporation was suggested by Crowley [1]. In Crowley s model the membrane is viewed as the isotropic elastic material. The necessary background for understanding its voltage-induced instability was discussed in Section II. Crowley s approximation for the elasticity energy term in Eq. (7) is... [Pg.82]

The first equation gives the rate of gas consumption as moles of gas (n) versus time. This is the only state variable that is measured. The initial number of moles, nO is known. The intrinsic rate constant, K is the only unknown model parameter and it enters the first model equation through the Hatta number y. The Hatta number is given by the following equation... [Pg.315]

In 1899, the nickel-cadmium battery, the first alkaline battery, was invented by a Swedish scientist named Waldmar Jungner. The special feature of this battery was its potential to be recharged. In construction, nickel and cadmium electrodes in a potassium hydroxide solution, it was the first battery to use an alkaline electrolyte. This battery was commercialized in Sweden in 1910 and reached the Unites States in 1946. The first models were robust and had significantly better energy density than lead-acid batteries, but nevertheless, their wide use was limited because of the high costs. [Pg.1306]

In order to investigate the single electron donation process from a reduced flavin to a pyrimidine dimer or oxetane lesion, the photolyase model compounds 1-4 depicted in Scheme 4 were prepared [41, 42]. The first model compounds 1 and 2 contain a cyclobutane uracil (1) or thymine (2) dimer covalently connected to a flavin, which is the active electron donating subunit in photolyases. These model systems were dissolved in various solvents... [Pg.203]

The first model is more suited to dealing with mixed flow such as bubble flow and slug flow, while the second is more suited to cases where flow is separated, as in stratified and annular flow. [Pg.198]

Two distinctive models were developed in order to investigate the effectiveness of PIS operational philosophy. The first model is separated into two parts. The first part is used to determine the optimal throughput when there is zero intermediate storage available. Two situations were studied. Firstly the model was solved without the use of the PIS operational philosophy. Secondly, the model was solved with the PIS operational philosophy. In the simple example shown in this section a 50% increase in the throughput was achieved when the PIS operational philosophy was used. In both cases the models developed were a MILP, thus guaranteeing global optimality. [Pg.66]

The second part of the first model was used to determine the minimum amount of intermediate storage required to achieve the same throughput achieved when there is... [Pg.66]

In the first model, the relaxation time is still given by the Rouse form... [Pg.92]


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Application of the First Principle Model to Spacecraft Operations for Aging

The Schlogl model of first-order phase transition

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