Processing of Biologies

The processing of biologies on a scale comparable to that of the previous material classes is as yet unknown, at least with regard to biomaterials for use in the human body. Most artificial biologies, both hard and soft, serve as scaffolds for the in situ manufacture of tissues that is, the human body is actually the processing center in which the raw materials it provides are used to fabricate some portion of the component (e.g., bone or skin). Even when the component is fabricated almost entirely 

Despite these observations, there are some common processing techniques that are emerging in the area of processing of biologies, as self-contained biomedical devices become more widely utilized. We examine two such areas in this section collagen processing and surface modification. 

As described in Section 1.5.3, collagen is one of the most useful and abundant substances in the human body. Both skin and tendon are composed of collagen, and in its purified form, collagen can be used for a wide variety of tissue repair applications. Let us briefly examine the processing of collagen. 

The purified collagen obtained from either of these techniques is subjected to additional processing to fabricate the materials into useful devices for specific medical applications. Some of these matrices and their medical applications are shown in Table 7.19 and will be briefly described. 

Membrane (sheet, film) Oral tissue repair wound dressings dura repair patches 

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This chapter discusses the composition, structure, and dynamic processes of biological membranes. 

Thus, in the observation of the drying process of biological materials, the water activity is at least as valuable as the water content of a material. As water activity measurements are complete in about 3 min, they represent a useful tool for control of the drying process. 

The biological cycle — that may encompass processes of biological transformation, plant uptake, bioaccumulation, soil organisms transformations and others. 

If all this is correct, then there must be some process of biological embedding wherein life experiences condition individual biological responses, which lead to systematic differences in resilience and vulnerability to disease across the range of social class experience. 

Theoretically, according to the mechanism of biological azo dye reduction, the processes of biological decolorization are oxidation-reduction reactions, in which transfer of electrons match with the proton flow by the help of coenzymes, such as NADPH/NADP+ and NADH/NAD+. The oxidation-reduction potentials of the couples of NADPH/NADP+ and NADH/NAD+ are -324 and -320 mV, respectively [25, 46]. The least AGo value of the conversion NADPH/NADP+ and NADH/NAD+ is 44 kJ [47]. Therefore, —93 mV, which is obtained from (1), could be considered as a rough limited ORP value for ordinary primary electron donors of the third mechanism of biological azo dye reduction. This was demonstrated by the results of many researches (Table 1). Hence, the observed failure of cyanocobala-min [30] and ethyl viologen [48] to act as a mediator is most probably due to their too low Ed values 530 and —480 mV, respectively. 

FUNDAMENTALS AND LIMITING PROCESSES OF BIOLOGICAL HYDROGEN PRODUCTION... 

Fundamentals and limiting Processes of Biological Hydrogen Production... 

Photodyncimics of metalloporphyrins have been extensively investigated on account of its importance in the understanding of photosynthesis and other processes of biological importance ( ). Particular atten-sion has been paid to the reason why the excited metalloporphyrins possess unique characteristics from the viewpoint of redox (2-4), energy transfer ( ), and other photodynamical processes (6,7). In comparison with the considerable knowledge accumulated on the photochemical properties of the lowest excited states, little has been known on the S2 - Sq fluorescence and Si Sq internal conversion processes which can also be regarded as unusual characters of metalloporphyrins. 

D. Jou J. E. Llebot (1990) Introduction to the Thermodynamics Processes of Biological Processes, Prentice Hall, New York. 

Low cortisol levels may impede the process of biologic recovery from stress, resulting in a cascade of alterations that lead to intrusive recollections of the event, avoidance of reminders of the event, and symptoms of hyperarousal. This failure may represent an alternative trajectory to the normal process of adaptation and recovery after a traumatic event. 

The incorporation of redox-active organometallic units within or on the periphery of dendritic structures is an especially challenging target because such molecules ate good candidates to play a key role as multielectron transfer mediators in electrocatalytic processes of biological and industrial importance. In particular, the organometallic ferrocene moiety is an attractive redox center to integrate into dendritic structures, not only because it is electrochemically well behaved in most... 

Nitrification is a vital step in the process of biological elimination of nitrogen in sewage plants. The consortium of microorganisms involved in this process is usually very sensitive to many pollutants from different industrial and agricultural sources. The rapid detection of such pollutants is essential for processing of sewage. 

Many of the problems encountered in the processing of biological materials are similar to those found in other areas of chemical engineering, and the separation processes used are frequently developments from counterparts in the chemical industry. However, biological materials frequently have rheological properties which make then difficult to handle, and the fact that their density differs little from that of water and the interfacial tensions are low can give rise to difficulties in physical separation of product. 

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