Molecular gigantism

The hydrothermal systems, hundreds of meters under the surface of the ocean, would have protected evolving systems from the high-energy cosmic radiation as well as from meteorite impacts. Even partial evaporation of sea water, due to gigantic impacts, could have been resisted by molecular systems present at great depths (Holm and Andersson, 1995). 

The study of protein synthesis offers another important reward a look at a world of RNA catalysts that may have existed before the dawn of life as we know it. Researchers have elucidated the structure of bacterial ribosomes, revealing the workings of cellular protein synthesis in beautiful molecular detail. And what did they find Proteins are synthesized by a gigantic RNA enzyme ... 

Exercise 29-2 Suppose a bottle of 1,3-cyclopentadiene were held at a temperature at which polymerization is rapid, but depolymerization is insignificant. Would the polymerization result in conversion of all of the 1,3-cyclopentadiene into essentially one gigantic molecule Why or why not How would you carry on the polymerization so as to favor formation of polymer molecules with high molecular weights ... 

In networks the molecular chains are connected by strong primary chemical links in fact a network is a single gigantic molecule. Networks can be formed in two different... 

Dorleans A, Knossow M, Gigant B (2007) In Zhou J (ed) Microtubule protocols (methods in molecular medicine). Humana, Totowa, NJ, p 235... 

Vesicles have molecular masses in the order of 10 -10 daltons. Van der Waals attraction between such gigantic solutes is very large. Nevertheless, vesicles do not precipitate but stay in solution, because the ultrathin membranes undulate. 

The molecular weight of a proteoglycan monomer prepared from bovine nasal septa has been reported as two to three million daltons ( ), for example. This monomer is bound to a hyaluronic acid backbone reversibly and noncovalently. The gigantic proteoglycan thus formed is stabilized by link proteins. 

Liquids vary in their rate of evaporation. Naturally in a mixture of liquids, some evaporate more rapidly than others. For example, if the solvent constituent of a lacquer evaporates more rapidly than the diluent, the limit of tolerance of the residual mixture is exceeded and gelling or precipitation occurs. As evaporation goes on, gigantic molecular reactions take place. Vast numbers of molecules change places as the new aggregates are formed. Some are... 

There is a new attitude in medicine these days personalized medicine, based on molecular diagnostics, comes into focus. This practice could not have evolved without new high-throughput screening (HTS) laboratory methods, which can detect many analytes in a very short time. On the other hand, the analysis of so many results created by HTS techniques could not be explained without the gigantic development of bioinformatics [12]. 

Even though all chemical reactions take place at the molecular scale, the gigantic number of reacting molecules allows the use of relatively simple expressions (such as the law of mass action) to describe the average kinetics at the macroscopic scale. Thus, the macroscopic kinetics of emulsion polymerization can be described in relatively undemanding terms. 

The above discussion provides summary of QSPR/QSAR approaches applied to classical, chemical compounds. However, an analysis devoted to nanomaterials having gigantic and complex molecular architecture lead to necessity of definition of new approaches for the predictive modelling, because the representation of their molecular structure by means of molecular graph and/or SMILES sometimes becomes very problematic (e.g. multi-walled carbon nanotubes [34], graphene [35]). In the first approximation, the optimal descriptors for such species should be a collector of all available data which are able to impact the physicochemical and/or biochemical behavior of nanomaterials. This concept is displayed in Fig. 12.6. 

Thus, in fact, endpoints related to traditional substances (i.e. non nanomaterials) represent phenomena basically defined by the molecular architecture which involves a modest number of atoms (e.g. less than 100). In contrast, endpoints related to nanomaterials are phenomena basically governed by many other factors besides the molecular characteristics of gigantic systems. 

Molecular Mode of Action Metabolic Effects Gigantism and Acromegaly Hypopituitarism Dwarfism... 

Petroleum feedstocks are complex hydrocarbon mixtures characterized by their intricate structural nature and composition at the molecular level. For process modeling purposes, this translates into a gigantic reaction network. 

Basically, a polymer is made up of many repeating molecular units formed by sequential addition of monomer molecules to one another. Many monomer molecules of A, say 1,000 to 1 million, can be linked to form a gigantic polymeric molecule ... 

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