Microscopic procedure

Microscopy (qv) plays a key role in examining trace evidence owing to the small size of the evidence and a desire to use nondestmctive testing (qv) techniques whenever possible. Polarizing light microscopy (43,44) is a method of choice for crystalline materials. Microscopy and microchemical analysis techniques (45,46) work well on small samples, are relatively nondestmctive, and are fast. Evidence such as sod, minerals, synthetic fibers, explosive debris, foodstuff, cosmetics (qv), and the like, lend themselves to this technique as do comparison microscopy, refractive index, and density comparisons with known specimens. Other microscopic procedures involving infrared, visible, and ultraviolet spectroscopy (qv) also are used to examine many types of trace evidence. 

The dehydration, embedding, and sectioning of pre-embedding electron microscopic immunocytochemistry blocks follow the standard electron microscopic procedures. However, for section staining, the time is reduced to 2-3 min to preserve the size of the silver particles. 

Hamilton and Lone applied a scanning electron microscopic procedure to understand this phenomenon [15]. Electron micrographs of razor-shaved individuals revealed frank skin cuts, the clipping of hair produced less skin trauma, and depilatory agents caused no injury to the skin. The increased infection rates observed were likely the result of compromise to the natural barrier function of the skin. 

Details on microscopic procedures are described in Section VIII. 

In the present writer s opinion, this summary of selected papers indicates that a detailed understanding of the raw feed mineralogy-particle size relationship and the effects of the temperature profile in a kiln is absolutely mandatory for continued quality control. These papers, and many others of similar subject matter, demonstrate the practicality of cement plant microscopy. The microscope, perhaps better than any other instrument of analysis, and certainly as a corroborative tool, provides the means for visual appreciation of the cement-making process. But what kind of training is necessary What are the essential microscopical observations and the "standard" microscopical procedures that one can use to help ensure a quality product Knowing the microscopical nature of the raw materials is the first step. 

After one becomes familiar with the microscopical aspects of the quarry rocks and the raw feed, evaluation of the feed with the use of burnability equations or other routine microscopical procedures can be initiated. Burnability equations help us to organize om thought about the suitability of various raw materials — that is, how easily they combine in the kiln — and can provide a basis for feed comparison and improvement, even though the equations are not used to determine free lime produced in a laboratory test. 

The antibody-coated bacteria test is another microscopic procedure that has been applied to tracheal aspirates from intubated patients. The results from one study were similar to those reported for sputa from patients not receiving ventilation, with low sensitivity in detection of pneumonia (48%-73%) but excellent specificity (98%-100%) (46). In another study, however, specificity was only 56% when compared to quantitative PSB cultures (47). It has also been suggested that a positive antibody-coated test (1) may precede a subsequent infection, (2) may be positive when quantitative culture results are low because of prior antimicrobial treatment or poor specimen handling or processing, and (3) may show antibiotic effectiveness by conversion to a negative test after treatment. 

The term biocompatible adhesive includes any natural or synthetic adhesive that interfaces with living tissues and biological fluids, and is suitable for short-/long-term biomedical applications. These surgical glues are particularly useful as replacement or support for sutures that are sometimes difficult to manipulate during laparoscopic or microscopic procedures, or... 

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