Some Unanswered Questions

The first part of this article argued the case that biological electrochemical reactions represent the power source for all driven biological phenomena. We now examine the mechanisms that control the rate of power generation and utilization in living systems. Intimately related to this is the question of how the rate of heat production by living cells is regulated. 

Another area of considerable conceptual difficulty relates to the observation that the adult animal exists in a more-or-less steady-state, well removed from equilibrium. When observed day-to-day there is generally little variation in body composition while the animal is on a consistent diet, the mass of protein, carbohydrate, and fat remaining approximately constant. This constancy is maintained despite the rapid turnover of the body s constituents. The living system is not static but dynamic, the steady-state being maintained because synthetic reactions exactly balance degradative processes. How this balance is achieved and what governs the overall rate of metabolic flux and heat production are the main topics of this section. 

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We have learned a great deal about comets in the intervening centuries, but there still remain some unanswered questions. 

During the past few years, experiment and theory have converged to a number of explicit answers regarding the location and electronic structure of hydrogen or muonium in semiconductors. Anomalous muonium, which had remained a puzzle for many years, now appears to be well understood in terms of the bond-center model. It is, oddly enough, normal muonium that still seems to pose some unanswered questions is it located at T itself or does it tunnel among various sites How does its rapid diffusion proceed ... 

Some Unanswered Questions Opportunities for Future Studies.396... 

SOME UNANSWERED QUESTIONS OPPORTUNITIES FOR FUTURE STUDIES... 

Tearing energy can be computed by finite element analysis and Yeoh150 has applied this to some classical test piece shapes to address some unanswered questions. 

While our proposed mechanism was interesting, it left some unanswered questions. What was the nature of the catalyst complex and more importantly, why was this not behaving like a classic acid catalysis Boe [11, 12] had postulated protonation of the alkoxy species followed by SN2 attack by the alcohol nucleophile. This is consistent with the negative value that he found for p. This does not agree though with the idea of a catalyst complex, nor does it agree with the findings reported here of a positive value of p. 

Water drops in the atmosphere can contain dissolved ions and organic compounds, and solid dust can condense these drops on its surface. There are a lot of data on the climatic impact of aerosols (Kondratyev et al., 2006a), but their role in the impact on biological processes due to the long-range transport of micro-organisms was studied inadequately. In connection with this, there are some unanswered questions. 

Kamel, K. S., Oh, M. S. and Halperin, M. L. (2002). Bartter s, Gitelman s, and Gordon s syndromes. From physiology to molecular biology and back, yet still some unanswered questions. Nephron. 92(Suppl. 1), 18-27. 

However, the scheme proposed to explain the effect of Ni ions on the codeposition of Mo (Eqs. 42 and 43) leaves some unanswered questions. Equation (39) shows the interaction between two soluble ions, leading to the two-electron reduction of one of them, and the formation of a mixed-metal complex adsorbed on the surface. All these processes cannot happen in a single step, but the authors did not specify what actually is assumed to happen Is [NiCit]- first adsorbed on the surface and then acts as the catalyst for the reduction of Mo04 to M0O2 Or, perhaps, the two ions form a mixed-metal complex in solution, which is subsequently adsorbed and reduced ... 

McMillan DE. 1999. A brief history of the neurobehavioral toxicity of manganese Some unanswered questions. Neurotoxicology 20 499-508. 

The reader will have noted that some unanswered questions were left in some of our earlier sections. For example, recall Reference 34 cited in Section V. A we did not evaluate on which side the equilibrium for reaction 54 lies. Because we subsequently considered the thermochemistry of sulphonyl sulphenates, we can now provide a partial, but admittedly long-winded, answer for the Ar = Ph species (46). The reader is reminded that A Hf(g, 46) — 52 kcal mol 1 and of the finding of Turecek and coworkers34 that the heat of formation of gaseous benzenesulphenic acid (84) is —8 kcal mol-1. Likewise, the reader may recall from Section VII.D our estimation for solid benzenesulphonic acid that AH (s, 20) = — 117 kcal mol- L These data cannot be immediately combined because of the discrepancy in the state for which the three species other than H20 are known. Do we wish to consider condensed phase species, in which case we need the sublimation energy of the sulphonyl sulphenate 46 and the sulphenic acid 84, or to consider gas phase species, in which case we need the sublimation energy of the sulphonic acid 20 ... 

Unresolved Problems Against the background of above listed achievements, there are still some unanswered questions that appear in the course of the research. These include, in particular, the mechanism of condensation energy transfer from a low-volatility product to a reactant, and the influence of the symmetry of the reactant crystal structure on the composition of the gaseous decomposition products. It would be worthwhile to perform a more thorough analysis of the dependence of the t coefficient and the sizes of the condensate particles on the vapour oversaturation of the low-volatility product, as well as of the relative contributions of the condensation and self-cooling effects to the underestimation of enthalpies determined by the second-law and Arrhenius plot methods. 

Compelling evidence demonstrates that CIA targets and modulates specific components of the innate and adaptive immune system. We will review animal studies as well as pilot studies in humans and discuss some unanswered questions on immunomodulation. All of which, should be addressed through additional basic research and well-designed human intervention studies. 

The investigation of the chiroptical properties of low and higji molecular weight compounds containing aromatic chromophores are of great interest in connection with some unanswered questions in the field of synthetic and natural polymers [1]. 

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