Human-Made Variations

There are many legal medicines that use opiates or opiate-like substances. Most of the opiate-based medicines used today are not made from natural opiates, but are either synthetic or semi-synthetic. Synthetic opiate drugs are not actually opiates at all they are merely different chemicals that act like opiates. Semi-synthetics are those drugs that involve changing the chemical structure of a natural opiate. An example of this is heroin, which is a human-made variation of morphine. Morphine and codeine are the principal natural opiates used as medicines and what follows are descriptions of the other most frequently used opiate-based medicines. 

The best known example of human-made variations in the isotopic composition of a metal is that of U enrichment. Almost all natural uranium has (nearly) the same isotopic composition, with 99.27% 0.72% and 0.006% The Oklo... 

Finally, in the context of elemental assay via isotope dilution and tracer experiments using stable isotopes, an isotopically enriched spike or tracer is added to a sample wherein the element of interest typically shows the natural isotopic composition. These isotopically enriched spikes are another example of human-made variations. 

The sharp public distinction between natural (produced by evolution or created by God—which for the purposes of this story, does not matter— and human made substances is only a delusion. This assumption was once a scientific theory, it was called the vis vitalis theory and was thoroughly discredited almost two centuries ago. The modern-day variation of this theory posits that hving things add some sort of extra good nutrients to materials, which cannot be produced in any artificial way. Table 1.3 presents a set of toxicity data (given as values) on natural and artificial substances. Even a cursory look on these data will reveal that natural toxins have the distinction of being among the most poisonous substances known. 

Below we will describe some individual cases where we think that may be possible to pinpoint the cause for isotopic variations, and will try to give a general idea of human variations that can be found in Europe. The characterization will not be comprehensive, given the fact that we have only recently started analyzing and comparing isotopic data across Europe, but we hope that a start can be made with matching actually observed variations and the causes behind them. 

From the standpoint of general interest the variations in the musculature of human hands are worthy of attention, especially so since it is often supposed that the human hand is a standard piece of equipment which all normal people possess. The writer has seen a magnificently produced motion picture using a highly involved model, which showed just how every intricate movement of "the hand" is made. There was no hint, however, that hands do not all work in the same way. 

A note should be made on the dominance of a-HBCD in human samples, which is likely to occur because of a diastereomeric shift due to the preferential metabolism of p-HBCD and y-HBCD by cytochrome P450 [34]. Several studies have reported the dominance of a-HBCD in human serum [7]. In contrast, some studies reported y-HBCD to contribute to a higher percentage of the total HBCDs in human tissues [23, 26]. An increase in the percentage of y-HBCD has been reported in highly exposed population and in occupationally exposed workers, with y-HBCD making up to 40% of E-HBCDs [23, 35]. Although the reasons for the different isomer profiles in human tissues from different studies are not yet clear, it is reasonable to hypothesize that they arise from a combination of differences in external exposures (e.g., a-HBCD predominated in both dust and diet of the present study) and interindividual variations in metabolism. 

There are broadly two uses of chemometrics that interest the process chemist. The first of these is simply data display. It is a truism that the human eye is the best analytical tool, and by displaying multivariate data in a way that can be easily assimilated by eye a number of diagnostic assessments can be made of the state of health of a process, or of reasons for its failure [ 153], a process known as MSPC [154—156]. The key concept in MSPC is the acknowledgement that variability in process quality can arise not just by variation in single process parameters such as temperature, but by subtle combinations of process parameters. This source of product variability would be missed by simple control charts for the individual process parameters. This is also the concept behind the use of experimental design during process development in order to identify such variability in the minimum number of experiments. 

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