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Background to the Study

In this new millennium, during which human activity will bring about unprecedented change in the natural world, ocean scientists are called upon to address a variety of important challenges. The National Research Council (1998) chose to highlight three related research areas in a report. [Pg.7]

Opportunities in Ocean Sciences Challenges on the Horizon. The focal areas selected were  [Pg.7]

This report also notes that the oceans still remain too vastly undersampled in time and space to adequately address these global-scale longterm challenges. [Pg.7]

However, this is not a recent development. A 1971 report of the Marine Chemistry Panel of the National Academy of Sciences Committee on Oceanography wrote that  [Pg.8]

The rapid advance of marine science involves the participation of [Pg.8]

All the samples here are from relatively intact young men, tall in stature, probably all from the American Northeast. A study of their collagen 5 C and 5 N isotope values, done to contribute to ascertainment of nationality, demonstrated a relatively broad range of variability (Katzenberg 1991). This variability was interpreted as being consistent with their probable origins [Pg.143]

Midshaft cross sections of all available femora (n = 23) were initially prepared for histologieal study. Most of the specimens showed a soft, chalky consistency with an intact subperiosteal layer, whieh tended to break away from the mideortieal material. There was no histologieal evidenee for fungal ingrowth from either subperiosteal or endosteal surfaces. Foci of destruction are consistent with descriptions of bacterial intrusion (Fig. 7.2, Pfeiffer 1995). [Pg.145]

Subsequent investigation into what features might distinguish the femur from Burial 8 initially foeused on the mineral fraction of a selection of Snake Hill femora. Energy dispersive x-ray microanalysis (JEOL JSM-35C SEM equipped with a TN-5500 X-ray analyzer) demonstrated consistent calcium to [Pg.145]

This outcome was consistent with a hypothesis that structural deterioration could have been a byproduct of microorganism activity. The higher lipid content in the poorly preserved tissue suggests that those lipids are primarily extrinsic, that is, that they were produced by bacteria and/or fungi. As the food source for such microorganisms, the protein within the bone may have been substantially altered in concert with the microstructure deterioration. The quantification of the changes to the organic fraction became our next focus of research. [Pg.147]

The eight samples are from burials distributed across the excavated area. In addition to these partitioned samples, bone powder that had the lipids removed was also available from three of the samples in the partitioned set (Burials 1, 8 and 20), as well as two other samples (Burial 17 and 24). These samples included bone from the entire cross-section. [Pg.148]


A 5-(methylthio)methyl-substituted derivative (cis-28) of ( + )-3-PPP has been reported [91]. The background to the study was the structural similarity between pergolide (29) and (cis-28). However, the biological testing of (cis-28) showed that it is inactive in vivo (GBL model), while an in vitro assay (inhibition of tyrosine hydroxylation) showed (cis-28) to be equipotent to racemic 3-PPP itself. These results indicate that the steric bulk in (cis-28) is not compatible with potent DA receptor interaction. However, since compound (cis-28) was not resolved, there is a possibility that one or both of the enantiomers of (cis-28) might have antagonistic properties [89]. [Pg.199]

The background to the studies described below has been discussed in earlier reviews (Reichardt, 1965 Reichardt and Dimroth, 1968 Kosower, 1968 Dack, 1970), and also in the text by Bethell and Gold (1967). [Pg.32]

This two-volume treatise is intended as an introduction for mathematicians and biologists with a mathematical background to the study of stochastic processes and their applications in medicine and biology. It is both a textbook and a survey of the most recent developments in this field. [Pg.129]

WE HAVE NOW studied the structures and typical reactions of the major types of organic functional groups. Further, we have examined the structures of carbohydrates, amino acids and proteins, nucleic acids, and lipids. Now let us apply this background to the study of the organic chemistry of metabolism. In this chapter, we study three key metabolic pathways glycolysis, the citric acid cycle, and the /3-oxidation of fatty acids. The first is a pathway by which glucose is converted to pyruvate and then to acetyl coenzyme A. The second is a pathway by which the hydrocarbon chains of fatty acids are degraded, two carbons at a time, to acetyl coenzyme A. The third is the pathway by which the carbon skeletons of carbohydrates, fatty acids, and proteins are oxidized to carbon dioxide. [Pg.700]

In Chapter VI, Ohm and Deumens present their electron nuclear dynamics (END) time-dependent, nonadiabatic, theoretical, and computational approach to the study of molecular processes. This approach stresses the analysis of such processes in terms of dynamical, time-evolving states rather than stationary molecular states. Thus, rovibrational and scattering states are reduced to less prominent roles as is the case in most modem wavepacket treatments of molecular reaction dynamics. Unlike most theoretical methods, END also relegates electronic stationary states, potential energy surfaces, adiabatic and diabatic descriptions, and nonadiabatic coupling terms to the background in favor of a dynamic, time-evolving description of all electrons. [Pg.770]

It is noteworthy that several studies exhibit contradictory results for both the mechanical and thermal characteristics of the flow. This is generally due to differences in the many parameters that characterize these studies such as the geometry, shape and surface roughness of the channels, the fluid, the boundary conditions and the measuring methodology itself. These discrepancies indicate the need for extension of the experimental base to provide the necessary background to the theoretical model. [Pg.82]

We assume that our readers have a background in science attainable by completing a university level course in introductory chemistry. We also expect our readers to be involved in one of the disciplines integral to the study of biogeochemical cycles. This includes appropriate subdisciplines of chemistry, biology, and geology, and the sciences that deal with soils, atmospheres, and oceans. [Pg.551]

The opening chapter gives some historical background to the investigation of high-energy processes. The discussions in the subsequent chapters proceed from current studies in the gas phase, to examination of liquid-phase techniques, and finally to applications in the solid state. The final chapters provide a perspective on current and future industrial applications of the field. [Pg.5]

In this chapter, we briefly discuss the theoretical background of polarized x-ray absorption spectroscopy (PXAS). Many of the recent applications of synchrotron radiation to polarized absorption edge structure and to EXAFS are discussed, with particular emphasis being given to the study of discrete molecular systems. We present here some indication of the potential applications of PXAS to systems of chemical and biological interest. [Pg.413]

In the previous chapters, the fundamental areas of thermodynamics and chemical kinetics were reviewed. These areas provide the background for the study of very fast reacting systems, termed explosions. In order for flames (deflagrations) or detonations to propagate, the reaction kinetics must be fast—that is, the mixture must be explosive. [Pg.75]

The investigator s brochure provides more detail than the protocol in relation to the background of the study, and should help to facilitate a better understanding of the rationale for the protocol and its key features. In an ideal world, the potential investigator will receive the investigator s brochure before deciding to participate in the study. The brochure should provide the investigator with sufficient information to decide if the... [Pg.246]


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The background

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