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\begin{center}
\begin{tabular}{C{2.0cm} L{0.19\linewidth} L{0.19\linewidth} L{0.19\linewidth} L{0.19\linewidth}}

& \textbf{A} & \textbf{B} & \textbf{C} & \textbf{D} \\[0.4em]

% proActiv
proActiv &
\includegraphics[width=\linewidth]{brain/proactiv/overall/overall_promoter_activity_category_percentage.pdf} &
\includegraphics[width=\linewidth]{brain/proactiv/overall/overall_promoter_activity_position_category.pdf} &
\includegraphics[width=\linewidth]{brain/proactiv/overall/overall_promoter_activity_single_multiple_category.pdf} &
\includegraphics[width=\linewidth]{brain/proactiv/overall/overall_promoter_activity_geneexpression_correlation.pdf} \\[-0.4em]

% Salmon
Salmon &
\includegraphics[width=\linewidth]{brain/salmon/overall/overall_promoter_activity_category_percentage.pdf} &
\includegraphics[width=\linewidth]{brain/salmon/overall/overall_promoter_activity_position_category.pdf} &
\includegraphics[width=\linewidth]{brain/salmon/overall/overall_promoter_activity_single_multiple_category.pdf} &
\includegraphics[width=\linewidth]{brain/salmon/overall/overall_promoter_activity_geneexpression_correlation.pdf} \\[-0.4em]

% DEXSeq
DEXSeq &
\includegraphics[width=\linewidth]{brain/dexseq/overall/overall_promoter_activity_category_percentage.pdf} &
\includegraphics[width=\linewidth]{brain/dexseq/overall/overall_promoter_activity_position_category.pdf} &
\includegraphics[width=\linewidth]{brain/dexseq/overall/overall_promoter_activity_single_multiple_category.pdf} &
\includegraphics[width=\linewidth]{brain/dexseq/overall/overall_promoter_activity_geneexpression_correlation.pdf} \\[-0.4em]

% CAGE
CAGE &
\includegraphics[width=\linewidth]{brain/cage/overall_promoter_activity_category_percentage.pdf} &
\includegraphics[width=\linewidth]{brain/cage/overall_promoter_activity_position_category.pdf} &
\includegraphics[width=\linewidth]{brain/cage/overall_promoter_activity_single_multiple_category.pdf} &
\includegraphics[width=\linewidth]{brain/cage/overall_promoter_activity_geneexpression_correlation.pdf} \\

\end{tabular}
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