Primary needs

The improvement of the quality of a design is seen as the primary need of industry, but to facilitate this we need appropriate methods for predicting quality and evaluating the long-term quality of an engineer s design (Morup, 1993 Russell and Taylor, 1995 Shah, 1998 Taguchi et al., 1989). However, there is relatively little work... 

FIGURE 23.38 The oxidative steps of the pentose phosphate pathway can be bypassed if the primary need is for ribose-5-P. 

The primary need for gas-solid separation processes is for gas cleaning the removal of dispersed finely divided solids (dust) and liquid mists from gas streams. Process gas streams must often be cleaned up to prevent contamination of catalysts or products, and to avoid damage to equipment, such as compressors. Also, effluent gas streams must be cleaned to comply with air-pollution regulations and for reasons of hygiene, to remove toxic and other hazardous materials see IChemE (1992). 

After six years of study on the problem of grain storage in 40 different countries, the writer arrives at the conclusion that the use of pesticides is one of the important phases of protection of stored products, but not the most important in the solution. The primary need is for better facilities in which to store grain or other products so that pesticides can be used effectively. If better facilities cannot be obtained, at least better management is needed before pesticides can be used satisfactorily. This is in the interest of efficient, continued, and increased use of pesticides. 

A stretch of DNA that is transcribed as a single continuous RNA strand is called a transcription unit. A unit of transcription may contain one or more sequences encoding different polypeptide chains (translational open reading frames, ORF) or cistrons. The transcription unit is sometimes termed the primary transcript, pre-messenger RNA or heterogeneous nuclear RNA (hnRNA). The primary transcript is further processed to produce mRNA in a form that is relatively stable and readily participates in translation. In order to understand the primary need for processing of this RNA, the biochemical definition of a gene must be discussed. 

The primary need of receptor modeling today is a general theory within which to operate. Each specific receptor model application should be derivable from this framework. If not, either the application of the theory is incorrect, or the theory must be changed. Throanorton and Axetell have compiled the applications. Henry J and Watson 2) have outlined the theory including some of those applications. The theory must be expanded to include them all. 

Although Vaccinia was eliminated from the international scene as recently as two decades ago, terrorism fears have generated renewed interest in the large-scale protection of an unprotected population against the disease, which has occasionally reappeared as a result of laboratory accidents and, in some cases, of deliberate dissemination of the virus. This is one example of the primary need for protection against the disease and for suitable vaccine delivery systems. 

The presentation in this chapter dwells rather heavily on the classification, measurement, and interpretation of non-Newtonian behavior. These rheological fundamentals have frequently been presented in literature which is unfamiliar to the engineer and have usually included much discussion of factors which at the present time are of minor engineering interest. Accordingly, it was felt that one of the primary needs in this field was a concise summary of these fundamentals and common definitions. It is hoped that thereby future developments may be undertaken in an orderly and rigorous manner, as contrasted to the relatively fruitless empiricism which has enveloped areas of this field in the past. 

Common heterotrophs depend on preformed organic compounds for all three primary needs. Although some carbon dioxide is fixed in heterotrophic metabolism, the het-erotrophic cell thrives at the expense of compounds formed by other cells, and is not capable of the net conversion (fixation) of carbon dioxide into organic compounds. Some bacteria referred to as photoheterotrophs are able to regenerate ATP photochemically but cannot use photochemical reactions to supply electrons to NADP+. Such organisms are like other heterotrophs in their dependence on preformed organic compounds. But because of their photochemical... 

What controls and other systems need to be put in place to ensure the customer s primary needs and objectives are met and to develop a long-term relationship with the customer ... 

Many models exist to predict the conditions within these sites (e.g., 34,35). However, if the primary need is to determine the extent of corrosion damage (e.g., the depth of corrosion penetration), these models are not sufficient. Generally, electrochemical techniques contain no spatial information, since the current measured is the sum of currents from all individual corrosion sites. In the case of pitting, this limitation is being slowly erased as scanning techniques capable of spatial resolution are being developed. However, the ability to resolve local corrosion sites within fixed occluded areas such as cracks and crevices remains minimal. 

If the roots, stem, or leaves don t receive all of the essential life-producing elements, there will be a breakdown of all the related processes because the plant functions as a whole. Failure to tend to one primary need may precipitate the breakdown of all the other processes of the plant. 

Since the evolution of traditional pharmacopeias has been predicated upon time-honored empirical testing, customary herbal remedies continue to be used by a vast majority of the world s population who depend on traditional medicine for their primary needs. Worldwide, the practice of herbalism continues to expand, and it has been estimated that the industry estimated at 60 billion today will significantly expand during this century (World Health Organization [WHO], 2004). To prove parameters of efficacy, more and more are being clinically evaluated in the context of use. Many have also been found to possess specific bioreactive compounds linked to their medical value, which in turn not only has verified their therapeutic worth, but also has led to new and significant drug discoveries (Lewis and... 

The need for fundamental and applied research on lifetime under service conditions is great. As a result, the subjects of dielectric breakdown, fatigue, wear, creep, fracture, oxidation, photodegradation, additive migration, etc., are increasingly important to the eflFective use of synthetic polymers. The development of a scientific basis for tests that predict accurately the useful service life is a primary need. 

In cases where one site is thought to give rise to a primary isotope effect - one in which bonds are being made or broken at the isotopic element - the subscripts will be used. In cases where secondary isotope effects (by definition, those that are not primary) need to be distinguished, the superscripts will be used. The middle part of Eq. (11.1) illustrates one use of the notation, as a primary H/T isotope effect measured when D occupies a secondary site. As a final example, the right-hand part of Eq. (11.1) shows a Swain-Schaad exponent r defined for a single site of isotopic substitution. The HD subscript serves to connect the exponent to the H/D isotope effect it acts on to produce the H/T isotope effect. In this example, the superscripts were omitted because there is either no second site of isotopic substitution or, in all cases, the isotope is protium. 

When energy is the primary need, glycolysis and citric acid cycle intermediates are favored products. 

It was not until the 1950s, when scientists began working in earnest on the space program, that efficient, practical fuel cells were developed. If astronauts were to fly a space shuttle, supplies of water were needed to support their lives on board and a reliable source of electricity was needed to power the shuttle s many systems. Both of these primary needs were met with the development of the hydrogen fuel cell that controls the oxidation of hydrogen and provides both electricity and water. The cell produces no by-products to require disposal or storage on a space journey. 

In hilly regions where gully formation on clay and loam soils is a common, or possible, occurrence there is often a need for catch and cover crops if these can be fitted in between main crops with very little disturbance of the soil. Of course sod crops are preferable for such soils but they may be impractical for the type of agriculture common to the region. The primary need here is to keep the soil covered with some kind of vegetation as near continuously as possible, and if a green manure crop aids in doing this, then it probably should be used. 

Nitrogen is the one element above all others that we associate with growth. As pointed out in Chapter 14, it is a constituent of proteins, enzymes, chlorophyll, deoxyribonucleic acids that make up the genetic code, amino acids and many intermediates invplved in the synthesis of plant substances. It is characteristically present in comparatively large amounts in the growing tips of plants, hut it can move about readily from one part of the plant to another to meet the primary needs at the time. 

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