## 3 Results  
### LW-PLA Samples  
The results of the 1.5 cm diameter LW-PLA print jobs are illustrated in Table 2. The density of the samples printed at different temperatures and flow rates were found between 0.36 g/cm\({}^{3}\) and 1.21 g/cm\({}^{3}\) that correspond to mean HU values between \(-\)702.7 HU and +137.6 HU, respectively. Simple linear regression models were used to examine the relationships between the flow rate and density, flow rate and mean HU, and density and mean HU. These models demonstrated a strong fit to the data, as illustrated in Figure 6 (R\({}^{2}\) > 0.99).  
Figure 6: Simple linear regression models of flow rate versus mean HU obtained at printing temperatures ranging from 200 \({}^{\circ}\)C to 250 \({}^{\circ}\)C for LW-PLA samples. STD\({}_{\rm xy}\) values are illustrated in bars.  
On the other hand, Figure 7 illustrates various body parts with distinct mean HU values falling within the range achieved by the LW-PLA samples. The highest HU value achievable corresponds to the spongy bone, while the lowest corresponds to the lungs. In between, there are organs such as the heart, liver, stomach, spleen, pancreas, kidneys, and bladder, as well as adipose and muscular tissues, and glandular tissue.  
The standard deviation of the mean HU measured in the axial plane (STDxy) for the printed samples ranged from \(\pm 6.7\) to \(\pm 16.7\), with a median value of \(\pm 9.3\) HU and a third quartile value of \(\pm 11.9\) HU. Similar measurements performed on distilled water yielded an STDxy of \(\pm 7.5\) HU, and mean HU of \(-1.8\) HU. In addition to the assessment in the axial plane, the homogeneity of the samples is also evaluated along the longitudinal axis using  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \
\begin{tabular}{c} **Printing** \\ **Temperature** (°C) \\ \end{tabular} & **Flow Rate (\%)** & **Mass (g)** &
\begin{tabular}{c} **Density** \\ **(g/cm3)** \\ \end{tabular} & **Mean HU** & \(\pm\)**STDxy** & \(\pm\)**STDz** \\ \hline \multirow{4}{*}{200} & 100 & 4.22 & 1.19 & +141.4 & 7.1 & 1.1 \\ \cline{2-6}  & 90 & 3.88 & 1.10 & +17.6 & 16.7 & 9.0 \\ \cline{2-6}  & 80 & 3.52 & 1.00 & \(-119.6\) & 11.9 & 5.1 \\ \cline{2-6}  & 70 & 3.15 & 0.89 & \(-230.2\) & 9.6 & 2.3 \\ \cline{2-6}  & 60 & 2.79 & 0.79 & \(-340.7\) & 9.1 & 3.4 \\ \hline \multirow{4}{*}{210} & 100 & 4.27 & 1.21 & +137.6 & 7.3 & 2.1 \\ \cline{2-6}  & 90 & 3.86 & 1.09 & +4.0 & 14.6 & 2.2 \\ \cline{2-6}  & 80 & 3.49 & 0.99 & \(-116.3\) & 12.5 & 8.9 \\ \cline{2-6}  & 70 & 3.12 & 0.88 & \(-237.1\) & 10.9 & 4.4 \\ \cline{2-6}  & 60 & 2.77 & 0.78 & \(-346.1\) & 10.8 & 6.9 \\ \hline \multirow{4}{*}{220} & 90 & 3.85 & 1.09 & +13.5 & 10.1 & 5.1 \\ \cline{2-6}  & 80 & 3.52 & 1.00 & \(-74.2\) & 8.1 & 3.6 \\ \cline{2-6}  & 70 & 3.13 & 0.89 & \(-176.1\) & 7.6 & 7.4 \\ \cline{2-6}  & 60 & 2.75 & 0.78 & \(-296.4\) & 9.1 & 4.9 \\ \cline{2-6}  & 50 & 2.38 & 0.67 & \(-402.6\) & 11.8 & 4.9 STD\({}_{\rm z}\), which ranged from \(\pm\)1.1 HU to \(\pm\)9.0 HU. The measurements revealed a median value of \(\pm\)4.2 HU and a third quartile value of \(\pm\)5.4 HU. These results are notably higher than the corresponding finding in distilled water, which was measured as \(\pm\)0.6 HU.