Future research, some suggested

It has been the aim of this review to present the theories of polymer crystal growth and to compare their different assumptions. We have stressed their strengths and failings and tried to show how these are related to the underlying models. However, it is left to the reader to judge for him/herself the correctness or otherwise in each case. To conclude we first make some cautionary remarks, then summarize the models and finally suggest avenues for future research. 

How weeds produce their effect is the subject of continuing research. As rather recently defined, the negative effect of weeds on crop plants includes both competition and allelopathy (1.) and has been termed interference. Previous weed science research considered the competition component foremost and, usually, solely (e.g. 2). Allelopathy, however, has received some attention recently, with a number of symposia and reviews devoted to allelopathic effects. Some of these cover the effects of weeds on crops (3, 4, 5). In this chapter, I review the possible role of allelopathy in weed interference in crop production in the Mid-South. A second objective of this review is to indicate where research is needed and to suggest potential lines of future research, especially with respect to the developing role of conservation tillage practices in this region. 

This review has no final conclusions. The whole matter of P.E. spectra of volatile metal compounds is still under investigation the results obtained until now yield only a partial picture, and there are several fundamental problems still open, so generalized conclusions are not warranted at the present stage of research. However, some points regarding the significance of the P.E. spectroscopic technique in coordination chemistry are already self-evident. We shall try to identify open problems, lines of future research, and precautions to be taken both in the experimental research and in the interpretive work, at least in the form and to the extent suggested by the present partial stage of the development of research in this field. 

I would suggest that this emotions model or a similar one with an ethological basis could be used not only as a framework for organizing research on human behavior, but also as a heuristic device for identifying potential areas for future research. To illustrate the breadth of the emotions model, I will try to fit some examples of recent sociobiologi-cal research into it. 

TTie diversity in the type of Fe-S clusters associated with these enzymes, catalyzing apparently simple hydration and/or dehydration reactions, is striking. Taken together, these results suggest that some of the Fe-S clusters that have been assigned redox roles in various enzymes may actually be functioning as catalytic groups. Clearly the field of Fe-S proteins, which a decade ago seemed to be well understood, has developed into a dynamic and fertile area for future research endeavors. 

The goals of this paper are to discuss some of the major generalizations that can be made about allelopathic interactions, provide some examples of suggested roles, and focus on desirable future research applications. Only a few of the pertinent investigations are cited in illustrating major principles. 

Obviously these suggestions for future research in allelopathy are only a few of the large numbers that could be given. Hopefully, however, they may give some Impetus to progress in some vital areas of allelopathy. 

XI. Looking Ahead Some Suggested Priorities for Future Research... 

In sum, the ICP-MS analyses suggest that Olivella shells are subject to fairly significant post-depositional alteration as shells are exposed to midden soils over hundreds to thousands of years. While discouraging, it does not preclude the application of elemental compositional studies for shell-bead sourcing. Some elements, such as Sc, Zr, and Al, among others not discussed in detail here, remain fairly constant when taken as ratios against Ca. It is these elements that should be the subject of provenance analyses and that we will target in future research with Olivella shell. 

The use of traditional (unffactionated) heparin has therefore been replaced by LMWHs to a large extent.18,100 LMWHs are clearly safer and more convenient to their unfractionated counterparts, and these drugs have become the primary method of treating acute venous thrombosis.47,100 LMWHs are now used routinely to prevent or treat deep vein thrombosis (DVT) following various types of surgery or medical conditions (ischemic stroke, cancer).70,127 It has also been suggested that LMWHs will produce optimal effects if they are administered for more than a few days, and some patients who are at high risk for thrombosis may receive LMWHs via subcutaneous injection for several weeks or months.80 Future research will help determine the best way to use LMWHs to prevent or treat venous thrombosis in specific clinical situations. 

Each methodology has given its specific contribution and the combined use of these methodologies with other analytical tools will certainly help toward the development of this very exciting NOM research field. Also, many other new opportunities and research needs are identifiable for the future. Therefore, briefly, some suggestions are made, as possible future research opportunities ... 

In each chapter, a general overview of foundational concepts is given, together with a review of classical and recent literature related to the various topics covered. In detail, the first chapter provides a comprehensive introduction to the main topics of the book, whereas the last chapter presents some suggestions for future research activity in this field. 

Cell fractionation studies of five strains of cyanobacteria indicate that MAAs are located primarily (>90%) within the cytoplasm and not the cell sheaths, walls, or membranes.132 Extracellular placement of MAAs does occur in some cyanobacterial species that posses cellular sheath layers.134135 Extracellular MAAs are covalently bonded to oligosaccharide molecules embedded in the cyanobacterial sheath matrix and provide substantial protection to prevent photobleaching of chlorophyll within the cell. Intracellular or extracellular distributions of MAAs in eukaryotic cells have not been investigated. Based on the high MAA concentrations of Phaeocystis antarctica colonies, it has been suggested that MAAs are associated with the extracellular mucopolysaccharide matrix of the colony.125 This may be a more common phenomenon than currently recognized, and future research efforts will be necessary to further document extracellular occurrence of MAAs in cyanobacteria and algae. 

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