Critical first

Corona.iy Hea.rt Disea.se, A theory for atherogenesis (120) has been developed whereby oxidation of low density Hpoprotein (LDL) within the arterial wall is the critical first step. It has been hypothesized that sufficient intake of antioxidants would prevent oxidation of LDL and reduce development of coronary heart disease (122). Interest in determining the role of antioxidants in blocking LDL oxidation has led to the development of in vitro test systems. 

In order to understand the potency of a given molecule, project scientists must first understand the nature of the measurement used to generate the potency value. If the molecule in question is from a literature report, there may be no in-house data to examine, and in that case the synthesis of the compound and the development of an assay usually becomes a critical first step to understanding the project landscape at that point. More commonly, however, the compound in question has been identified in some type of in-house screening process. These can take many forms, but they can broadly be grouped into two major categories ... 

The critical first step in the acquisition of acute bacterial meningitis is nasopharyngeal colonization of the host by the bacterial pathogen. The bacteria first attach themselves to nasopharyngeal epithelial cells and are then phagocytized into the host s bloodstream. 

Cell/substrate contacts can be located by a nonfluorescence technique completely distinct from TIRF, known as internal reflection microscopy (IRM).(1 9) Using conventional illumination sources, IRM visualizes cell/substrate contacts as dark regions. IRM has the advantage that it does not require the cells to be labeled, but the disadvantages that it contains no information about biochemical specificities in the contact regions and that it is less sensitive to changes in contact distance (relative to TIRF) within the critical first lOOnm from the surface. 

All these results are encouraging for investigators planning to use X-ray diffraction in mixed solvents at subzero temperatures and the rest of the present article will be devoted to a discussion of methods and preliminary results in this field. The methodology for cryoprotection of protein crystals, its physical-chemical basis, and the specific problems raised by the crystalline state, as well as the devices used to collect data at subzero temperatures, will be described. Limitations and perspectives of the procedure will be discussed critically. First attempts to determine the structure of productive enzyme-substrate intermediates through stop-action pictures will be described, as well as investigations showing that X-ray diffraction at selected normal and subzero temperatures can reveal protein structural dynamics. 

We have already seen that water is a much weaker base than ammonia, because oxygen is more electronegative than nitrogen and its electrons are thus less likely to be donated to a proton. Neutral oxygen bases are also generally very much weaker than nitrogen bases. Nevertheless, protonation of an oxygen atom is a critical first step in many acid-catalysed reactions. 

Production of High-Performance Nickel Alloys. In the production of high-performance alloys, the critical first step of alloying requires sophisticated equipment, stringent controls, and expertise. Several production methods are used. 

In the hypothesis, Points 5 and 8 above (alternative structures) have come under criticism, first by Skovborg et al. (1992) and then by Natarajan et al. (1994). However, Skovborg noted that alternating structures may account for some of his nucleation data. A further criticism of the labile cluster hypothesis is that the energy barrier for agglomeration of clusters is far larger than cluster disintegration (Radhakrishnan and Trout, 2002). 

The process of understanding and using this guide begins with a most critical first step. We must know how these chemical data were collected. 

As a numerical example, suppose that we run the first reactor at 325 K and the second at 350 K. The resulting design has vessel volumes of 64.5 m3 with heat transfer areas of 74.8 m2. However, the percentage of the total AT driving force in the critical first reactor decreases only to 61%. This approach appears to be less effective than lowering both reactor temperatures. 

Extraction of the pyrrolizidine alkaloids and their N-oxides from plant sources is a critical first step in LG-MS analysis. Some methods of extraction already described (Section 13.2) consist simply of treatment with aqueous methanol and, following microfiltration (0.45 p.m), immediate LC-MS analysis with no further treatment. However, the aqueous methanol treatment will extract more than just the alkaloids. 

Clearly, the process described is not sufficient to create a shared performance culture, a process which takes years of joint effort. However, it is the critical first step in defining shared directions and shared modes of interaction as the platform for future growth at the level of each individual employee. 

A clinical suspicion of an Acanthamoeba infection is the critical first therapeutic step. Acanthamoeba can be diagnosed by eye smears, culture, tissue biopsy, polymerase chain reaction, and confocal microscopy. 

Crystallization is the critical first and most important step, because good single crystals usually provide quality diffraction. Linus Paullingonce entitled one of his lectures "The Importance of Being Crystalline" (3). Unfor-... 

Accordingly, a reaction mechanism has been proposed [113] which includes one-electron transfer from the arene donor to the high-valent metal within the EDA complex as the critical first step toward mercuration or thallation, (Eq. 27) ... 

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