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Direct Specimen Analysis

The enrichment of Salmonella from stool by cultivation overnight using a suitable selective liquid medium, inhibiting growth of other bacteria, followed by [Pg.434]

MALDI-TOF MS identification has also been reported [58], Such applications substituting the additional growth on agar plates accelerate the detection of particular microorganisms. They could also be envisioned for other samples and bacteria, for example. Streptococcus agalactiae from vaginal swabs or Listeria spp. and Campylobacter spp. from food samples. [Pg.435]


The capability of performing direct specimen analysis on whole blood and urine (nonprocessed samples)... [Pg.300]

Electrography — Electrography, introduced independently by A. Glazunov and H. Fritz, is an obsolete technique for the direct electrochemical analysis of solid materials. The principle is that a solid specimen is pressed on a paper which is soaked with an electrolyte solution. By anodic oxidation of the surface of the solid specimen the reaction products (e.g., nickel(II) ions) react with a reagent in the paper (e.g., dimethylglyoxime) to give colored reaction product (red in case of nickel(II) and dimethylglyoxime). This produces a print that clearly shows the distribution of the reactive element (nickel, in our example) on the surface of the specimen. [Pg.220]

Direct immunohistochemical analysis of prostatic tissue has become very popular since the development of AR antibodies. However, a disadvantage of this technique in quantitative analysis is that the intensity of the immunohistochemical stain is dependent on the intactness of the structure of the AR. Therefore, mutations or alterations in the structure may reduce staining intensity (T5). Biochemical and immunohistochemical studies of AR content in relation to grade or stage of disease, as well as prediction of response to endocrine therapy, has been inconsistent. Nearly all primary prostate cancer specimens positively express AR protein, as determined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) analysis as well as by immunohistochemical analysis on formalin-fixed, paraffin-embedded primary prostate tissues (D12, H14). In advanced-stage prostate cancer, immunohistochemical techniques has shown that metastases in bone, the... [Pg.109]

This angle 9 is the complementary to the take-off angle [29] defined as the angle between the specimen surface and the mean direction of analysis. [Pg.289]

In another example study, Aicher et al [2001] examined damage in softwood specimens loaded in tension in plane normal to the tangential direction. Their analysis included source locations, and they note that the source-receiver distance should not exceed 100 mm for proper analysis. They were able to relate the AE source locations to damage localization, although they note that the characteristic rapid increase in AE event rate was not accompanied by a visible change in specimen stiffness. [Pg.315]

In the very thin deposits that were strained in the [110] and [120] direction TEM analysis revealed the presence of mechanical twins that occurred only near the fmeture line. As for the thin [100] specimens there was again no homogeneous plastic deformation in the gauge length. Only thicker samples showed some homogeneous plastic deformation prior to necking and rupture. [Pg.202]

UV microspectroscopic applications may find their origin in the fact that analytical problems in synthetics production and moulding are often associated with the determination of additives in polymers while only small sample quantities are available. Examples are the determination of stabiliser distributions or the characterisation of inhomogeneities in foils. Qualitative and quantitative characterisation of such small quantities by in-polymer UV spectrophotometry requires small pinholes (0 0.085 cm). Se-han et al. [401] have described a sample holder provision to allow for distribution analysis of phenolic stabilisers in polymers by direct UV analysis. For purposes of scanning (in mm steps) a specimen holder with x, y adjustments permits determination of the stabiliser concentration in desired increments of an industrially produced foil of relatively constant path length (200 /xm). This is a way to check the distribution of substances in polymers and, if required, to optimise the manufacturing process. [Pg.520]

The format of this chapter will follow the areas identified above with sections devoted to the analysis of substrate surfaces, the forensic analysis of failed adhesive joints and organic coatings, and a final section that will look at the methods in which the interfacial chemistry can be probed directly. Specimen preparation is an important part of this last section, and the particular methods relevant to adhesion research will be considered in some detail. The tenor of this chapter is to provide the adhesion scientist with an overview of the different hierarchies of information that can be obtained using surface analysis methods, throughout which there will be illustrations of work from the author s laboratory. [Pg.211]

The plateau of the adsorption isotherm indicates the concentration(s) at which all adsorption sites for the adsorbing species are occupied, in surface chemistry terms the fractional surface coverage of the substrate by the adsorbate is unity. Such a specimen provides an ideal opportunity to probe the interfecial chemistry of adhesion directly using what is sometimes referred to as the thin film approach. As the layer of organic material, such as adhesive, is very thin (as a result of monolayer coverage) the contribution of interfacial chemistry at the interface will be maximized in the resultant XPS or ToF-SIMS spectrum. For this reason, the construction of adsorption isotherms is often used as a precursor to direct interphase analysis in this manner. [Pg.228]

The magnitude of the velocity of an ultrasonic wave travelling in a low loss test piece is related to one or more of the stiffness components and the density. All the stiffness components can be determined from a single test piece if its dimensions allow experimental measurements to be performed along a sufficient number of directions. The analysis of the results is greatly simplified if wave propagation is carried out along the symmetry axes of the specimen. In this case... [Pg.551]

At X-ray fluorescence analysis (XRF) of samples of the limited weight is perspective to prepare for specimens as polymeric films on a basis of methylcellulose [1]. By the example of definition of heavy metals in film specimens have studied dependence of intensity of X-ray radiation from their chemical compound, surface density (P ) and the size (D) particles of the powder introduced to polymer. Have theoretically established, that the basic source of an error of results XRF is dependence of intensity (F) analytical lines of determined elements from a specimen. Thus the best account of variations P provides a method of the internal standard at change P from 2 up to 6 mg/sm the coefficient of variation describing an error of definition Mo, Zn, Cu, Co, Fe and Mn in a method of the direct external standard, reaches 40 %, and at use of a method of the internal standard (an element of comparison Ga) value does not exceed 2,2 %. Experiment within the limits of a casual error (V changes from 2,9 up to 7,4 %) has confirmed theoretical conclusions. [Pg.104]

The examples discussed above suggest useful directions for future research involving trace element analysis of bones. Specifically, the effects of developmental age and other factors (e.g., porosity, mineralization) that may lead to differences in surface area of specimens should be considered. Diage-netic effects should be monitored by analysis of a suite of elements whose abundances are not controlled by dietary abundances (e.g., Mn, Zr, etc.). Finally, although alkaline elements such as Sr and Ba are most likely to reflect the Sr/Ca and Ba/Ca levels of the diet, omnivores such as humans are likely to obtain the majority of these elements from plants rather than from animals. Therefore for accmate diet reconstruction it is necessary to determine the total abundance of Ca as and the Sr/Ca and Ba/Ca ratios of the plant and animal resources that were potential dietary staples. The effects of culinary practices on elemental abundances (Burton and Wright 1995 Katzenberg et al. this volume) must also be evaluated. [Pg.167]

For threatened or endangered species, or species of special concern, it is often necessary to analyze specimens that have died of causes not directly attributable to mercury. Bird eggs that have been abandoned or flooded out may be used for analyses. However, if the eggs were pushed out of the nest by parents that are incnbating the rest of the clntch, the reason for rejection of the egg must be considered in order to properly interpret mercury residue levels. Similarly, birds killed by predators may be suitable for analysis, but the internal tissues of sick or emaciated birds should not be nsed for residue analysis because in some studies, error has resulted from remobilization of mercury (Ensor etal. 1992 Sundlof etal. 1994). [Pg.130]


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Direct analysis

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