First Stage Tests

When a culture is examined microscopically for its morphological characteristics a number of points need to be noted. The initial one is the appearance of the cells, whether they are cocci or rods, and whether the cells are arranged singly, in filaments, in groups, or in chains. In a few groups of bacteria, it may be difficult to decide whether the cells are cocci or rods. This problem may be related to the stage of the growth cycle from which the cells were taken. 

If the results show that a Gram-positive organism is present, then the first stage tests shown in Table 1 should be carried out. If the organism is Gram-negative, then all the tests shown in Table 2 should be carried out. 

If spores are present, then the organism is either from the genus Bacillus or Clostridium. These can easily be distinguished as Bacillus is aerobic and Clostridium is anaerobic. Bacillus sometimes loses the ability to sporulate. This may be permanent, but can frequently be reversed by changing medium or by growing 

Modified with permission from Cowan and Steel s Manual for the Identification of Medical Bacteria , 3rd Edn., ed. G.I. Barrow and R.K.A. Feltham, Cambridge University Press, 1993. 

---

Pharmacopeia First-Stage Testing (N=10) Second-Stage Testing (additional 20)... 

FIRST STAGE TESTS IN IDENTIFYING BACTERIAL ISOLATES... 

Table 1 Gram positive bacteria (first stage tests)... 

The first stage in any inspection is to generate a proeedure which is specific to the component being examined in many instances, such a procedure will be based on a standard such as CEN J5I/-EN1714 Non-Destructive Testing of Welds - Ultrasonic Examination of Welded Joints . CamuS incorporates a tool ProcGen to provide assistance with this task. 

A melamine laminating resin used to saturate the print and overlay papers of a typical decorative laminate might contain two moles of formaldehyde for each mole of melamine. In order to inhibit crystallization of methylo1 melamines, the reaction is continued until about one-fourth of the reaction product has been converted to low molecular weight polymer. A simple deterrnination of free formaldehyde may be used to foUow the first stage of the reaction, and the build-up of polymer in the reaction mixture may be followed by cloud-point dilution or viscosity tests. 

A much more severe test is that leading to UL-94-5V classifications. This involves two stages. In the first stage a standard 5 X 0.5 inch bar is mounted vertically and subjected to a 5 inch flame five times for 5 seconds duration with an interval of 5 seconds. To pass the specification no specimen may bum with... 

The Osprey River facility is about to undergo a revolution Osprey River has been selected for a pilot study to integrate all aspects of EHS into a single management system. This is the first stage of what will be a company-wide project. The pilot project will b e used to test the design and installation strategies and to firm up the costs and benefits of the overall project. 

In all tests, the temperature in the first- and second-stage reactors was kept within the necessary temperature limits of 288°-482°C. Because the carbon monoxide concentration was low in many of the tests, the second stage was not used to full capacity as is indicated by the temperature rise in runs 23, 24, and 27. The temperature profile shows the characteristic rise to a steady value. With the space velocities used (<5000 ft3/ft3 hr), the temperature profile is fully developed in the first stage within 30.0 in. of the top of the catalyst bed. A characteristic dip in temperature was observed over the first 8-10 in. of the catalyst bed in all runs. This temperature profile may indicate the presence of deactivated catalyst in this region, but, until the catalyst can be removed for examination, the cause of the temperature drop cannot be determined. There is no evidence that this low temperature zone is becoming progressively deeper. It is possible that an unrecorded brief upset in the purification system may have poisoned some of the top catalyst layers. 

When step (a) reaches equilibrium, both and 8 should have steady state values. To test this hypothesis, we determined the effect of exposure time on and 8 for N80 steel in 15% HC1 at 25 C and in 28% HC1 at 65 C, as shown in Figures 6 and 7, respectively. Here [octynol] = 3.5 x 10"% in 15% HC1 and 2.1 x lO"2 in 28% HC1. It is immediately apparent from these plots that neither nor 8 reaches a steady state value during the course of the experiments. Although appears to be relatively constant throughout the 15% HC1 test and during the first stage of the 28% HC1 test, it is continually increasing in both cases. 

Following a published procedure for converting substituted anilines to isatins by reaction with chloral hydrate and hydroxylamine [1], it was noticed that at the end of the first stage (formation of an isonitrosoacetanilide), the odour of hydrogen cyanide was present, and this was confirmed by a Prussian blue test [2], In related work, concentrations of 100-200 ppm of hydrogren cyanide were found [3]. A mechanism for its formation from chloral hydrate and hydroxylamine was proposed [2], and the need for appropriate precautions was stressed [2,3],... 

Apart from specifications as to origin, e.g. palm kernel oil, fats are normally supplied on the basis of established parameters. One of these is the iodine value. This reflects the tendency of iodine to react with double bonds. Thus, the higher the iodine value the more saturated the fat is. An iodine value of 86 would approximate to one double bond per chain, while an iodine value of 172 approximates to two double bonds per chain. Another parameter is the peroxide value. This attempts to measure the susceptibility of the fat or oil to free radical oxidation. The test is applied on a freshly produced oil and measures the hydroperoxides present. These hydroperoxides are the first stage of the oxidation process. Obviously, this test would not give reliable results if applied on a stale sample. 

For that purpose, interesting strains, which have been identified in the first stage of the screening system should be further analyzed not only by an in vitro test, but also by techniques which enable an exact determination of the respective in vivo activity. This... 

When a comparison of two separate replicate sets of data is required, the first stage is normally to compare their respective precisions by means of the F-test. This test uses the ratio of the variances of the two sets to establish any statistically significant difference in precision. F is calculated from... 

In the first stage in order to test the process of various types of polymer films were surface-fluorinated. From 1990 to 1994 it was shown that XeF2 could be used effectively for surface fluorination of a variety of plastics. Polyethylene film and plates,18 aromatic polysulfone,19 polyvinyltrimethylsilane,20 and polycarbonate,21 among other polymeric materials, were fluorinated successfully. 

The first stage in producing a score from a result x (a single measurement of analyte concentration in a test material) is to obtain an estimate of the bias, thus ... 

Unnecessary animal testing can be avoided by relying on in vitro studies as the first stage acute toxicity and cytocompatibility test for injectable materials (Pearce et al., 2007). Many researchers have utilized in vitro studies to screen the cellular response to CNTs (Raja et al., 2007) and to investigate the various CNT-mammalian cell interactions such as oxidative stress (Manna et al., 2005 Shvedova et al., 2003, 2007), antiproliferative effects (Cui et al., 2005 Garibaldi et al., 2006), decreased cell adhesion (Cui et al., 2005), apoptosis (Bottini et al., 2006 Cui et al., 2005 Jia et al., 2005), and necrosis (Jia et al., 2005). A summary of these in vitro studies are presented in Table 12.1. 

To test the hypothesis that the screw channels were not designed properly such that a pressure exists in the channels underneath the vent opening, the process was numerically simulated. The simulation of the first stage was performed at a rate of 461 kg/h while the second stage was at 410 kg/h. The estimated axial pressures for the process are shown in Fig. 13.13. 

---