Model topography

Bornstein et al.. Simulation of Urban Earner Effects on Polluted Urban Boundary Layers Using the Three-Dimensional URBMET TVM Model with Urban Topography, Air Pollution Proceedings, 1993. 

KD Ball, RS Beii y, RE Kunz, E-Y Li, A Proykova, DJ Wales. Erom topographies to dynamics of multidimensional potential energy surfaces of atomic clusters. Science 271 963-966, 1996. RS Berry, N Elmaci, JP Rose, B Vekhter. Linking topography of its potential surface with the dynamics of folding of a protein model. Proc Natl Acad Sci USA 94 9520-9524, 1997. Z Guo, D Thii-umalai. J Mol Biol 263 323-343, 1996. 

The tools available for site selection include climatological data, topography, population data, emission inventory data, and diffusion modeling. Climatological data are useful in relating meteorology to emission patterns. For example, elevated levels of photochemical oxidant are generally related... 

Recent revisions to the boundary conditions (ice-sheet topography and sea surface temperatures) have added uncertainty to many of the GCM calculations of the past two decades. Moreover, all of these calculations use prescriptions for at least one central component of the climate system, generally oceanic heat transport and/or sea surface temperatures. This limits the predictive benefit of the models. Nonetheless, these models are the only appropriate way to integrate physical models of diverse aspects of the Earth systems into a unified climate prediction tool. 

The results of all of these topography studies are summarized in Fig. 1. The open eircles indicate residues of the H -ATPase shown in one way or another to be located on the cytoplasmic side of the membrane and the closed circles indicate residues in membrane-embedded segments. The lines in the sequence indicate minor regions with locations as yet not established. Thus, the topographical locations of nearly all of the 919 residues in the molecule have been established. It should be emphasized that the exact points of entry and exit of the polypeptide chain into and out of the membrane are not implied in the model. 

Fig. 1. Model for the transmembrane topography of the H -ATPase. OUT and IN indicate points of reference outside and inside an intact cell, respectively. See text for additional details.

Except for the two additional membrane-spanning stretches in the second membrane-embedded segment, the proposed membrane-embedded stretches indicated in Fig. 1 are similar to those proposed for the closely related Ca -ATPase [53]. In fact, the overall topography proposed in Fig. 1 is quite similar to the Ca -ATPase model, lending additional credibility to each. 

Martel P, Makriyannis A, Mavromoustakos T, Kelly K, Jeffrey KR. Topography of tetrahydrocannabinol in model membranes using neutron diffraction. Biochim Biophys Acta 1993 1151 51-58. 

As we have seen in the previous chapter, the apparent topography and corrugation of thin oxide films as imaged by STM may vary drastically as a function of the sample bias. This will of course play an important role in the determination of cluster sizes with STM, which will be discussed in the following section. The determination of the size of the metallic nanoparticles on oxide films is a crucial issue in the investigation of model catalysts since the reactivity of the particles may be closely related to their size. Therefore, the investigation of reactions on model catalysts calls for a precise determination of the particle size. If the sizes of the metal particles on an oxidic support are measured by STM, two different effects, which distort the size measurement, have to be taken into account. 

The problems associated with the application of this (or any other) model have been discussed. Because of the form of the typical isotherm, which exhibits a broad plateau region, fitting of experimental results to the model requires that data be obtained over a very broad range of concentrations. This is often very difficult to accomplish in practice, especially when difference methods are used to determine the amount of polymer adsorbed. Evaluation of adsorption in real systems is further complicated by a lack of knowledge of the available solid surface area. The latter may be affected by particle size, shape and surface topography and by polymer bridging between particles. 

The GR15 and T42 topography originate from the ET0P05 [NOAA (1988)] data set interpolated onto the model grid. Hereby, specific topographic features, such as the important conduits of overflows and throughflows, were adjusted to observed depths [Marsland et al (2003)]. 

Profiles in the Japanese Sea are similar for model and observational data. Concentration decreases down to 1000 m and remains constant below. Surface concentrations are lower for modeled profiles, most likely due to the emission scenario, that assumes identical temporal behaviour for all source points and does not capture all emitted mass. Due to the limited horizontal resolution of models, the topography of the ocean differs from the real one. In the Southern ocean concentrations were low throughout all depths, and for the measurements often below the detection limit of 6 pg/L. 

---