Specimen automated

Blood and urine are most often analyzed for alcohol by headspace gas chromatography (qv) using an internal standard, eg, 1-propanol. Assays are straightforward and lend themselves to automation (see Automated instrumentation). Urine samples are collected as a voided specimen, ie, subjects must void their bladders, wait about 20 minutes, and then provide the urine sample. Voided urine samples provide the most accurate deterrnination of blood alcohol concentrations. Voided urine alcohol concentrations are divided by a factor of 1.3 to determine the equivalent blood alcohol concentration. The 1.3 value is used because urine has approximately one-third more water in it than blood and, at equiUbrium, there is about one-third more alcohol in the urine as in the blood. 

More recent developments in the rolling ball area include an automated micro viscometer, the Paar AMV 200, from Paar Physica. The specimen to be measured is introduced into a glass capillary down which a gold-covered steel ball roUs. The rolling time is measured automatically. The shear stress may be varied by changing the inclination angle of the capillary tube. The shear rate range is 10 1000, which makes the instmment useflil for... 

A fully automated microscale indentor known as the Nano Indentor is available from Nano Instmments (257—259). Used with the Berkovich diamond indentor, this system has load and displacement resolutions of 0.3 N and 0.16 nm, respectively. Multiple indentations can be made on one specimen with spatial accuracy of better than 200 nm using a computer controlled sample manipulation table. This allows spatial mapping of mechanical properties. Hardness and elastic modulus are typically measured (259,260) but time-dependent phenomena such as creep and adhesive strength can also be monitored. 

X-Ray fluorescence (XRF) analysis favorably differs from other instmmental techniques by rapidity, automation ability, selectivity, accuracy. Quality of specimen obtained from sample to be analyzed has influence to the accuracy. 

Figure 7. Configuration of the materials durability test system 1, Zymark robot arm 2, Mettler balance 3, blotting station 4, capping station 5, specimen rack 6, water bath 7, block oven 8, vacuum oven 9, freezing chamber 10, NDT station 11, automated micrometer, and 12, washing station. O, specimen holder.

The labor-intensive nature of polymer tensile and flexure tests makes them logical candidates for automation. We have developed a fully automated instrument for performing these tests on rigid materials. The instrument is comprised of an Instron universal tester, a Zymark laboratory robot, a Digital Equipment Corporation minicomputer, and custom-made accessories to manipulate the specimens and measure their dimensions automatically. Our system allows us to determine the tensile or flexural properties of over one hundred specimens without human intervention, and it has significantly improved the productivity of our laboratory. This paper describes the structure and performance of our system, and it compares the relative costs of manual versus automated testing. 

Setup an Automated Test Series. Before testing can begin the user must identify the specimen bars in the magazine and specify the test conditions. This is accomplished with setup routines which prompt the user to define the test series. At various points the user is given the opportunity to go back and correct erroneous entries. The information provided by the user is stored in a queue file to be accessed later by the data acquisition software. 

Automated flexure tests are similar. The robot moves the bottom bar from the magazine to the measuring device where its width and thickness are determined, then it places the bar on the flexure test fixture. The PDP-11/44 begins the test by putting the crosshead in motion. Data collection begins when the first load is detected, and the test continues until the specimen bar breaks, the load cell maximum force is reached, or a specified maximum strain value is reached. Then the crosshead is stopped, the specimen is ejected from the fixture, and the crosshead is returned to its initial position. This process is repeated until the test series is complete. 

Web-based data collection and management systems provide a mechanism for remote data entry, where entered data are added to a centralized database once the submit button is pressed. They can be designed to automate the various aspects of clinical trials such as eligibility evaluation, data collection, and tracking specimens. They also serve as a resource site for participating sites to access trial-specific information, facilitate communication, track data queries and their resolutions, and allow administrative management of trials [28, 29]. For these reasons, they play an important role in facilitating the conduct of international clinical trials. 

At present, calcium and magnesium are estimated almost exclusively by atomic absorption (36). Present instrumentation permits the dilution of the specimen to approximately 1 - 100 for calcium and even higher for magnesium. For many instruments, the two elements are not read out simultaneously such as is practicable for sodium and potassium with the flame photometer. The lower limit of serum volime at present, for the practical assay for calciim and magnesiim in the laboratory of Neonatology, is approximately 10 ul The instruments are very readily automated, and it is not uncommon for results to be available at the rate of 240 per hour in the routine laboratory, where a typical atomic absorption instrument such as a Perkin-Elmer has been attached to an automatic feed system. 

They employed a FIB of 30 keV Ga ions which as focused to a spot with a diameter which could be varied between 0.05 and 1 pm. The beam current varied with focus size between 13 pA and 1.2 nA, and sputter rate typically increased with beam current from 0.005 to 0.5pm3s 1. The beam control was automated, so that the major part of the specimen preparation was performed automatically, only the final high-resolution operations being carried out by manual adjustment of the milling area. Their preparation scheme was as follows ... 

Stereological methods have often been used without the advantage of a computer or video screen. Such an approach superimposes a grid of dots, lines or areas on the specimen image and counts the inclusions and intersections this grid format shows with the feature of interest within the specimen field. Such a procedure, without automation, is most laborious requiring much effort to establish statistical validity for the measurements. 

Commercial application of the dendrimer-based reagent technology has been demonstrated by the successful development of The Stratus CS STAT fluorometric analyzer [5] marketed by Dade Behring Inc. This rapid automated point of care immunoassay system provides quantitative analysis of whole blood or preprocessed plasma samples via unit use assay test packs. Up to four test packs can be introduced for each sample. All reagents [5-9] required for specimen analyses are contained within the test packs. 

In 1980 Bemhardsson et introduced an automated electrochemical method for CPT determination. The specimen is mounted as described in Section IV.2 (ii) using a stream of argon to avoid crevice corrosion and 0.02-5% sodium chloride as electrolyte. The CPT is determined by a potentiostatic test method using an instrument called the Santron CDT 400 for potential control, temperature control, and current measurements. 

As with most instruments, erroneous results may be obtained if the high resolution diffractometer is not correctly set up. In modem instmments this is greatly assisted by the manufacturers, by prealigned components, permanent alignment on installation and by automated algorithms for specimen alignment. The primary errors to be considered are... 

Immunocytochemical methods have become an integral part of the clinical laboratory, as well as the research setting (see Chapter 50). Clinically relevant specimens ranging from frozen sections and cell-touch preparations to whole-tissue samples are amenable to analysis (see Chapters 9-13). Panels of antibodies have been developed to aid in the differential diagnosis of tumors (see Chapter 51), and automated instrumentation has been designed to speed the handling of numerous specimens (see Chapter 52). 

In uremia there are present in the serum a variety of known and unknown metabolites that can produce aberrant laboratory results. Significant differences in glucose concentration have been observed in such specimens analyzed by ferricyanide (F2a) or Fe (II)-5-pyridylbenzo-diazepin-2-one reduction methods compared to glucose oxidase procedures (K7a). In a patient with elevated creatinine (15 mg/100 ml) and uric acid (10 mg/100 ml), the glucose value determined by the automated alkaline ferricyanide procedure was overestimated by 20 mg/100 ml (C4). In uremic patients undergoing chronic hemodialysis there is a decrease in transaminase activity. In 11 of 19 such patients, there was... 

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