Editing Final Report/Thesis 2016 (section)

==Task 2 Mass Spectrometer isotope Data Analysis==
===Relative research===
1.Hair elements
Hair analysis can demonstrate the content level of the heavy mental and essential elements in human body. [19] The different value of some essential elements in hair may be correlated with nutritional status and diseases, such as calcium (Ca), chromium (Cr), zinc (Zn), copper (Cu), and selenium (Se). The high values of some elements such as lead (Pb), arsenic (As), mercury (Hg), and cadmium (Cd) in hair can indicate the intoxicating phenomenon. [19]
Using this analysis method can discover the useful information about the Somerton man healthy condition and has possibility to find the cause of death. 
2.The relation between living environment and hair elements 
The living environment can affect the content level of elements in human body. This effect not only caused by polluted water and food, but through the injury and radiation. Trace elements values in hair can reflect the source of behaviors including the diet hobbies, smoking and medication. Human absorbs pollution source by different ways such as oral, breath, injection and radiation. These contaminants stored in different body organs and tissues can affect human health. Hair is a good indicator of environment change. Normally, it shows the variation of trace element in human body as the hair growth.

=== Glass test data analysis ===
==== Data screening ====
The hair data was recorded by mass spectrometer and the data was got from glass test. There are 44 elements gained by laser ablation (shown in Table 1). Three of these elements are needed to be mentioned. The first one is sulphur (S7) which must exist in human’s hair. The value of Sulfer can be refered to the drift value of the environment. The second one is lead (Pb206), the high level of Lead is harmful for human health. The third one is strontium (Sr88). This element has high percentage in Adelaide’s soil compared with other areas. So, the analysis of the change tendency of Strontium’s value will provide useful information about Somerton man’s living environment before his death.
Table 1 Elements table for glass test

[[File:code1.jpg|thumb|500px|center|Table 1 Elements table for glass test]]
==== Element classification ====
Some recorded hair data contains toxic and heavy mental elements which are harmful for human health in high values. However, most are essential elements for human body. Table 2 shows the toxic elements and essential elements in hair. The comparison of toxic elements content in hair is an important research subject.[21]
Table 2 the Different Type Elements of Hair
[[File:somertontable2.png|center|Table 2 the Different Type Elements of Hair]]
In previous study, the hair data analysis is based on glass test result. However, the impurity material has influence on element values, thus, the data analysis mainly relies on quartz test rather than glass test in this project. Compared with glass plate, the quartz plate is a purity material composition. Table 3 shows the main composition of glass and quartz.
Table 3 The different Elements of Glass and Quartz
[[File:somertontable3.png|center|Table 3 The different Elements of Glass and Quartz]]

==== Element content comparison ====
In order to speculate the cause of death and living environment, the Somerton man hair data should be compared with control samples. In this experiment, six normal people’s hairs are selected as control samples. Then, the mass hair data is disposed by software for a visual comparison.
Excel  
At first, the hair data of Somerton man was plotted by Excel (shown in Figure 6). The X axis demonstrates the scan time of mass spectrometer. The Y axis demonstrates the relative value of elements content.
Figure 1 Somerton man’s hair data
[[File:somertontable4.png|thumb|500px|center|Figure 6 Somerton man’s hair data]]
However, only 28 elements were shown on the chart. Some data was missing due to the shortage of Excel. Besides, most elements are not clear except sodium (Na23). Some traces are out of range and not obvious, such as the elements located on the bottom of this chart. So, these troubles result in the difficulties of contrast.
The control samples hair data plotted by Excel (shown on appendix A) as well. Unfortunately, they all have the shortages as the Somerton man’s data chart.
Matlab
In order to solve these problems, Matlab can be used to plot each element’s content distribution. 44 elements comparison figures have been plotted and shown on appendix A. Some comparison figures of element value display the results clearly. However, some figures have difficulties to find the tendency. The elements figures’ classification is shown on table 4.
Table 4 Classify elements by comparison results
[[File:code5.png|thumb|500px|center|Table 4 Classify elements by comparison results]]
The quality of the results is considered below, four elements (Na23, Mg24, Si29 and Ca43) have the similar tendency. Meanwhile these four elements are all contained in glass material in previous study. This phenomenon can assume that the recorded elements values are affected by glass slice. However, the elements which do not exist in the glass will not be affected.
In table 4, the same value means that the content of elements in the Somerton man and control samples can be regarded as the same value. Different value represents a significant difference in element content, and the change trend is not similar. No tendency means that the comparison figures can’t show the law of change and the results can’t be compared. Figure 7 shows the lead (Pb206) relative value comparison between Somerton man and control samples.
Figure 7 Lead (Pb206) Value Comparison 
[[File:code6.png|thumb|500px|center|Figure 7 Lead (Pb206) Value Comparison]]
The X axis demonstrates the scan time of mass spectrometer. The Y axis demonstrates the relative value of Lead content. The mass spectrometer scans from the root of hair. Therefore, the smaller number of X axis represents the closer to death time. In Figure 2, the content of lead in control samples is very low and there is slight upward trend only in a short period of time. However, there have found a very high level of Lead in Somerton man’s hair compared with control samples especially the end of his hair. This situation of high lead content is worthy of attention. Through further studying the distribution graph of lead content, it clearly shows a tendency that the lead value has a visual reduction before his death. So, it can be affirmed that high level of lead was not the main cause of his death. In fact, the high level of lead content can be related to the living environment and the rapid decline in lead content may represents the recent replacement of the living environment. Thus, some of the geographic information in 1948 needed to research, such as solid analysis, petroleum quality, water quality and nuclear power plant location.
Figure 8 shows the mercury (Hg202) relative value comparing between Somerton man and control samples.
Figure 8 Mercury (Hg202) Value Comparison
[[File:code7.png|thumb|500px|center|Figure 8 Mercury (Hg202) Value Comparison]]
The X axis demonstrates the scan time of mass spectrometer. The Y axis demonstrates the relative value of mercury content. There have found a higher level of mercury in Somerton man’s hair compared with control samples. This value from root to the end of hair is basically the same. Through research, mercury is a highly toxic heavy metal pollutants of biologic toxicity. It is difficult to be discharged back into the organism. So it is a serious threat to human health. However, mercury is ubiquitous in nature. There are trace amounts of mercury existing in plants animals and food. Normally, human can eliminate toxins through excretion and metabolism to keep the amount that should not influence health. This is the reason for finding mercury in human’s hair. The main pollution of mercury is from chlor-alkali, plastics, batteries, electronics and other industrial emissions. The Somerton man’s higher level of mercury may be due to his living area. Thus, this should not be regarded as the cause of his death.
The strontium value between the Somerton man and control samples’ hair are obviously different. Figure 4 shows the strontium (Sr88) relative value comparing between Somerton man and control samples.
Figure 9 Strontium (Sr88) Value Comparison
[[File:code8.png|thumb|500px|center|Figure 9 Strontium (Sr88) Value Comparison]]
The X axis demonstrates the scan time of mass spectrometer. The Y axis demonstrates the relative value of strontium content. Strontium exists in mineral water. It is an essential element for human. This element can prevent hardening of the arteries. At the root of Somerton man hair, the content of strontium is significant high. This means the living area for Somerton man contains high level of strontium content before his death. In addition, the strontium value shows an increasing tendency in his last two weeks. However, strontium is not a toxic element and the increasing tendency is not the cause for the death of Somerton man. Reasonable inference is that the Somerton man changes living environment two weeks before the death and this is the same with the speculation for lead content change. 
Moving-average Filter in Matlab
Some comparison figures cannot be shown clearly by Matlab plotting. Thus, the Moving-average Filter should be applied. Firstly, selecting a window size for Filter. Then, calculating the arithmetic average of outliers within the window and make the average of the demand as outlier’s window centre point. After that, moving the window as window size and the average method is repeated until this process is complete. This method has a good inhibitory effect on periodic disturbance and makes the figure smoother. It is suitable for high frequency oscillation system. 
All of the elements content figures have been plotted by using moving-average filter and shown on appendix B. After using moving-average filter, the comparison figures have some new founds, such that more similar tendency elements are found and some clear comparison figures have been shown. The details are shown on table 5.
Table 5 Classify elements by comparison results  
[[File:code9.png|thumb|500px|center|Table 5 Classify elements by comparison results ]]
Through filtering, As75, Ag107, Cd111 are the new found toxic elements which have high level in the Somerton man’s hair. The content distribution is shown as follow: 
Figure 10 Cadmium (Cd111) Value Comparison
[[File:code10.png|thumb|500px|center|Figure 10 Cadmium (Cd111) Value Comparison ]]
Cadmium is an element present in the nickel-cadmium battery and it is a toxic element which can create poison gas when boiled. The average content value of cadmium in Somerton man is much higher than control samples especially when the scan time is 1400 seconds. However, the change trend of this element are similar with lead and content value of cadmium shows a decreasing tend for his last time. Unlike lead, cadmium is more toxic and it can be regarded as the clue for the death of Somerton man. However, this kind of battery did not appear before 60 years. That can be indicate this battery is not the source of cadmium. It can also be observed from the figure that the hair for control samples contain cadmium as well. Thus, it can assume that this kind of element may come from drinking water or food, or other frequently used items. 
Figure 11 Silver (Ag107) Value Comparison
[[File:code11.png|thumb|500px|center|Figure 11 Silver (Ag107) Value Comparison ]]
Through the observation of Figure 6，the silver content of Somerton man is higher than control samples. Besides, the value change for silver in hair of Somerton man is not obvious and the whole tends to be stable. Thus, this element should not be used for the speculation of Somerton man living condition. Besides, the element of silver is not harmful for human healthy. It can only make some colour change for skin. Thus, this element will not be researched in this project.
Figure12 Arsenic (As75) Value Comparison
[[File:code12.png|thumb|500px|center|Figure12 Arsenic (As75) Value Comparison ]]
Arsenic content level in Somerton man is increasing during the last two week. At the tip of Somerton hair, the arsenic content is similar with control samples. That means this content level is not harmful for human. Besides, the living area of Somerton can be assumed as same as control samples. However, the arsenic level is significant high at his last few days and the arsenic can be used for making toxicant. So, changing living area or being poisoned should be considered. This comparison figure can be regarded as one valuable clue.

=== Quartz test data analysis ===
==== Data screening ====
Compared with glass plate, quartz plate is more pure. So, some elements recorded in the glass experiment were not present in the quartz test and some elements have different relative atomic weight. The recorded 35 elements in quartz test are shown in Table 6.
[[File:code13.png|thumb|500px|center|Table 6 Recorded Elements on Quartz Test ]]
==== Data comparison figures ====
All of the quartz data is recorded. In order to comparison, the data of element has been classified as four sets of data: 
•	Control sample hairs: Files name are Hair02-Hair08. For control hairs, it analyzed 2 sections of each hair, each 500um in length, so there are 0.7 centimeters control sample in total. The number of samples is seven, and each person takes two hairs as the two samples.
•	Somerton Man: It analyzed 500um sections, each subsequent transect beginning where the previous finished for a total of 96 sections (4.8cm total).
•	Standards: The files named NIST612-1 to NIST612-20 (20 transects) are standards and were run to ensure that the instrument wasn’t grifting too much during the analysis, they can be used to compensate for the drift if need be as they were run at intervals during the sample acquisition. 
•	Background: Transits of 100um lengths across the quartz, files are Glue -1 to Glue–4.
For the quartz test data, each element needs to plot three comparison figures. The first comparison is the comparison of four sets of data which are control samples, Somerthon man, quartz and standards. The second one is enlarged graph for the first comparison figure. The third figure shown fourteen control samples’ hair data comparison.
Using the different colour dots to represent the four sets of data. Blue dots represent control samples, red dots represent Somerton man, yellow dots represent standards and green dots represent quartz background. The Figures (13-19) show the comparison of four sets of data. The X axis for all of the figures describes the scan times of the laser. The Y axis represents the relative value of elements in four sets of data. 
[[File:code14.png|thumb|500px|center|Figure 13a Silver (Ag107) ]]
[[File:code15.png|thumb|500px|center|Figure 13b Silver (Ag107) ]]
[[File:code16.png|thumb|500px|center|Figure 13c Silver (Ag107) ]]
The comparison result of silver (Ag107) value between four sets of data is shown in Figure 8. Yellow dots represent the drift values which are basically stable and indicate that the drift change is not significant. Thus, the recorded data is reliable. Green dots represent the silver content in quartz. As can be seen from the figure, the content of silver in the quartz is very small. Therefore, this set of data has little effect on the test data. In general, the silver element content in Somerton man’s hair is higher than the control hairs. In quartz experiment, the relative content value of silver in the hair is a table value and it is similar with the glass experiment result. 
Figure 14 Carbon (C13)
[[File:code17.png|thumb|500px|center|Figure 14a Carbon (C13) ]]
[[File:code18.png|thumb|500px|center|Figure 14b Carbon (C13) ]]
[[File:code19.png|thumb|500px|center|Figure 14c Carbon (C13) ]]
Figure 15 Sulphur (S34)
[[File:code20.png|thumb|500px|center|Figure 15a Sulphur (S34) ]]
[[File:code21.png|thumb|500px|center|Figure 15b Sulphur (S34) ]]
[[File:code22.png|thumb|500px|center|Figure 15c Sulphur (S34) ]]
Same as silver, the standard values for sulphur and carbon are constant which means the instrument wasn’t drifting too much. By comparison, the carbon and sulphur relative values are similar among Somerton man and 12 control hairs. Only two samples have significant differences and these samples come from one special person. Carbon and sulphur are essential elements in human hair. The change in the content of these two elements can be a direct indicator of a person's living environment. Based on the comparison results of the Figure 9 and 10, the living environment conditions for Somerton man and six control samples are similar but different from the special one. Thus, the living environment of Somerton man can be confirmed.
Figure 16 Calcium (Ca43)
[[File:code23.png|thumb|500px|center|Figure 16 Calcium (Ca43) ]]
Figure 17 Potassium (K39)
[[File:code24.png|thumb|500px|center|Figure 17 Potassium (K39) ]]
Figure 18 Strontium (Sr88)
[[File:code25.png|thumb|500px|center|Figure 18 Strontium (Sr88) ]]
Compared with the elements relative values between Somerton man and control samples, Figure 11, 12, and 13 have some similarities. The relative values of calcium, potassium and strontium in Somerton man’ hair are higher than most control hairs. However, the content of these three elements in two samples is close to the content of Somerton man’ hair. Moreover, these two hair samples both are from the one person. Based this result, it can be speculated that the content values of these three elements in the living environment for Somerton man and this special sample are similar. 
Figure 19 Lead (Pb206)
[[File:code26.png|thumb|500px|center|Figure 19a Lead (Pb206) ]]
[[File:code27.png|thumb|500px|center|Figure 19b Lead (Pb206) ]]
[[File:code28.png|thumb|500px|center|Figure 19c Lead (Pb206) ]]
It has mentioned in the previous chapter that lead is a toxic element, and the data obtained from the glass plate experiment show that the lead content in Somerton man’s hair is significantly higher than that in control hairs. This phenomenon still exists in the quartz plate test. Since the incomplete hair for quartz plate test, the trend of lead content value in the hair before Somerton man dying cannot be expressed. However, the content of lead in Somerton man’s hair is indeed higher than the control hairs.
The difference in lead levels does not indicate that the death of Somerton man is caused by the high level of lead in the body. The difference may be due to the fact that the lead content in human living environment is different from 60 years ago. 
Figure 20 Comparison of the relative values of some elements in control hairs
[[File:code29.png|thumb|500px|center|Figure 20a Comparison of the relative values of some elements in control hairs ]]
[[File:code30.png|thumb|500px|center|Figure 20b Comparison of the relative values of some elements in control hairs ]]
For control hairs, two sections of each hair have been analysed. There are fourteen control hairs which are from seven persons. By comparing these 14 samples, it was found that there was a difference in the elemental content between the samples, especially the first control person’s hair. Figure 15 shows the relative value of the first sample is significantly higher than the other samples. These elements are Mg, Ca, K, Mn, Na, Li, Sr. In addition, by the analysis and comparison results of several previous graphs, the values of the elemental contents of this sample are similar to those of Somerton man. From this result it can be inferred that this control sample and Somerton man have similarities in the living environment or lifestyles.

=== Two data comparison ===
==== Two tests data comparison table ====
In the glass plate test and the quartz plate test, 31 same elements were recorded and shown in table 7.
Table 7 the Same Elements in Two Data Sets
[[File:code31.png|thumb|500px|center|Table 7 the Same Elements in Two Data Sets ]]
==== Comparison of Somerton man’s two hairs ====
In the last two chapters, we compare and analyze the differences between Somerton man and the control samples in the two experimental data. Next, the two experimental results of Somerton man's two hair data will be compared. We hope to compare the two groups of experimental data to find a same trend but different values data, and then multiply a constant number with one of the test data to obtain the other test data.
Figure 21 (a) Silicon (Si) value comparison in quartz test
[[File:code32.png|thumb|500px|center|Figure 21 (a) Silicon (Si) value comparison in quartz test ]]
Figure 21 (b) Comparison of the relative values of Silicon (Si) in Somerton man hair
[[File:code33.png|thumb|500px|center|Figure 21 (b) Comparison of the relative values of Silicon (Si) in Somerton man hair]]
Figure 16(a) is a comparison of the silicon data obtained in a quartz plate experiment. The silicon content in the standard is reduced. So that the silicon content in the hair data is reduced. It is shown that the environment of test has influence on test result. From Figure 21 (b), these two hairs of Somerton man have significant different in the relative value of silicon. Besides, the trend of these two sets of data is significantly different. Thus, it cannot find the constant number from Figure 21.
The following figures that from Figure 22 to 25 are the different elements comparison results of two Somerton man’s hairs. It is hard to find the same trend from this comparison. Therefore, it is necessary to find another suitable way to compare the two sets of data.
Figure 22 Comparison of the relative values of Arsenic (As75) in Somerton man hair
[[File:code34.png|thumb|500px|center|Figure 22 Comparison of the relative values of Arsenic (As75) in Somerton man hair]]
Figure 23 Comparison of the relative values of Strontium (Sr88) in Somerton man hair
[[File:code35.png|thumb|500px|center|Figure 23 Comparison of the relative values of Strontium (Sr88) in Somerton man hair]]
Figure 24 Comparison of the relative values of Lead (Pb206) in Somerton man hair
[[File:code36.png|thumb|500px|center|Figure 24 Comparison of the relative values of Lead (Pb206) in Somerton man hair]]
Figure 25 Comparison of the relative values of Sulphur (S34) in Somerton man hair
[[File:code37.png|thumb|500px|center|Figure 25 Comparison of the relative values of Sulphur (S34) in Somerton man hair]]