+\subsection{Getting Help on the Parameters for a Service}
+
+Each parameter available for a method usually has a short description, which
+Jalview will display as a tooltip, or as a text pane that can be opened under
+the parameter's controls. In the parameter shown in Figure
+\ref{clustalwparamdetail}, the description was opened by selecting the button on the left hand side. Online help for the
+service can also be accessed, by right clicking the button and selecting a URL
+from the pop-up menu that will open.
+
+\begin{figure}[htbp]
+\begin{center}
+\includegraphics[width=2.5in]{images/clustalwparamdetail.pdf}
+\caption{{\bf ClustalW parameter slider detail}. From the ClustalW {\sl Clustal $\Rightarrow$ Edit settings and run ...} dialog box. }
+\label{clustalwparamdetail}
+\end{center}
+\end{figure}
+
+\subsection{Alignment Presets}
+The different multiple alignment algorithms available from JABA vary greatly in
+the number of adjustable parameters, and it is often difficult to identify what
+are the best values for the sequences that you are trying to align. For these
+reasons, each JABA service may provide one or more presets -- which are
+pre-defined sets of parameters suited for particular types of alignment
+problem. For instance, the Muscle service provides the following presets:
+\begin{list}{$\bullet$}{}
+\item Large alignments (balanced)
+\item Protein alignments (fastest speed)
+\item Nucleotide alignments (fastest speed)
+\end{list}
+
+The presets are displayed in the JABA web services submenu, and can also be
+accessed from the parameter editing dialog box, which is opened by selecting
+the `{\sl Edit settings and run ...}' option from the web services menu. If you have used
+a preset, then it will be mentioned at the beginning of the job status file shown
+in the web service job progress window.
+
+\subsection{User Defined Presets}
+Jalview allows you to create your own presets for a particular service. To do
+this, select the `{\sl Edit settings and run ...}' option for your service,
+which will open a parameter editing dialog box like the one shown in Figure
+\ref{jwsparamsdialog}.
+
+The top row of this dialog allows you to browse the existing presets, and
+when editing a parameter set, allows you to change its nickname. As you
+adjust settings, buttons will appear at the top of the parameters dialog that
+allow you to Revert or Update the currently selected user preset with your changes, Delete the current preset, or Create a new preset, if none exists with the given name. In addition to the parameter set name, you can also provide a short
+description for the parameter set, which will be shown in the tooltip for the
+parameter set's entry in the web services menu.
+
+\subsubsection{Saving Parameter Sets}
+When creating a custom parameter set, you will be asked for a file name to save
+it. The location of the file is recorded in the Jalview user preferences in the
+same way as a custom alignment colourscheme, so when Jalview is launched again,
+it will show your custom preset amongst the options available for running the
+JABA service.
+
+%
+% \exercise{Creating and using user defined presets}{\label{createandusepreseex}
+% \exstep{Import the file at
+% \textsf{http://www.jalview.org/tutorial/fdx\_unaligned.fa} into jalview.}
+% \exstep{Use the `{\slDiscover Database Ids}' function to recover the PDB cross
+% references for the sequences.}
+% \exstep{Align the sequences using the default ClustalW parameters.}
+% \exstep{Use the `{\sl Edit and run..}'
+% option to open the ClustalW parameters dialog box, and create a new preset using
+% the following settings:
+% \begin{list}{$\bullet$}{}
+% \item BLOSUM matrix (unchanged)
+% \item Gap Opening and End Gap penalties = 0.05
+% \item Gap Extension and Separation penalties = 0.05
+% \end{list}
+%
+% As you edit the parameters, buttons will appear on the dialog box
+% allowing you revert your changes or save your settings as a new parameter
+% set.
+%
+% Before you save your settings, remeber to give them a meaningful name by editing
+% the text box at the top of the dialog box.
+% }
+% \exstep{Repeat the alignment using your new parameter set by selecting it from
+% the {\sl ClustalW Presets menu}.}
+% \exstep{These sequences have PDB structures associated with them, so it is
+% possible to compare the quality of the alignments.
+%
+% Use the {\sl View all {\bf N}
+% structures} option to calculate the superposition of 1fdn on 1fxd for both
+% alignments (refer to section \ref{superposestructs} for instructions). Which
+% alignment gives the best RMSD ? }
+% \exstep{Apply the same alignment parameter settings to the example alignment
+% (available from \textsf{http://www.jalview.org/examples/uniref50.fa}).
+%
+% Are there differences ? If not, why not ?
+% }
+% }
+
+\section{Protein Alignment Conservation Analysis}
+\label{aacons}
+The {\sl Web Service $\Rightarrow$ Conservation} menu controls the computation
+of up to 17 different amino acid conservation measures for the current alignment
+view. The JABAWS AACon Alignment Conservation Calculation Service, which is used
+to calculate these scores, provides a variety of standard measures described by
+Valdar in 2002\footnote{Scoring residue conservation. Valdar (2002) {\sl
+Proteins: Structure, Function, and Genetics} {\bf 43} 227-241.} as well as an efficient implementation of the SMERFs
+score developed by Manning et al. in 2008.\footnote{SMERFS Score Manning et al. {\sl BMC
+Bioinformatics} 2008, {\bf 9} 51 \href{http://dx.doi.org/10.1186/1471-2105-9-51}{doi:10.1186/1471-2105-9-51}}
+
+\subsection{Enabling and Disabling AACon Calculations}
+When the AACon Calculation entry in the {\sl Web Service $\Rightarrow$
+Conservation} menu is ticked, AACon calculations will be performed every time
+the alignment is modified. Selecting the menu item will enable or disable
+automatic recalculation.
+
+\subsection{Configuring which AACon Calculations are Performed}
+The {\sl Web Service $\Rightarrow$ Conservation $\Rightarrow$ Change AACon
+Settings ...} menu entry will open a web services parameter dialog for the
+currently configured AACon server. Standard presets are provided for quick and
+more expensive conservation calculations, and parameters are also provided to
+change the way that SMERFS calculations are performed.
+AACon settings for an alignment are saved in Jalview projects along with the
+latest calculation results.
+
+\subsection{Changing the Server used for AACon Calculations}
+If you are working with alignments too large to analyse with the public JABAWS
+server, then you will most likely have already configured additional JABAWS
+servers. By default, Jalview will chose the first AACon service available from
+the list of JABAWS servers available. If available, you can switch to use
+another AACon service by selecting it from the {\sl Web Service $\Rightarrow$
+Conservation $\Rightarrow$ Switch Server} submenu.
+
+\chapter{Analysis of Alignments}
+\label{alignanalysis}
+Jalview provides support for sequence analysis in two ways. A number of
+analytical methods are `built-in', these are accessed from the {\sl Calculate}
+alignment window menu. Computationally intensive analyses are run outside
+Jalview {\sl via} web services - and found under the
+{\sl Web Service} menu. In this section, we describe the built-in analysis
+capabilities common to both the Jalview Desktop and the JalviewLite applet.
+
+\section{PCA}
+Principal components analysis calculations create a spatial
+representation of the similarities within the current selection or the whole alignment if no selection has been made. After
+the calculation finishes, a 3D viewer displays each sequence as a point in
+3D `similarity space'. Sets of similar sequences tend to lie near each other in
+this space.
+Note: The calculation is computationally expensive, and may fail for very large
+sets of sequences - because the JVM has run out of memory. Memory issues, and
+how to overcome them, were discussed in Section \ref{memorylimits}.
+
+\subsubsection{What is PCA?}
+Principal components analysis is a technique for examining the structure of
+complex data sets. The components are a set of dimensions formed from the
+measured values in the data set, and the principal component is the one with the
+greatest magnitude, or length. The sets of measurements that differ the most
+should lie at either end of this principal axis, and the other axes correspond
+to less extreme patterns of variation in the data set.
+In this case, the components are generated by an eigenvector decomposition of
+the matrix formed from the sum of pairwise substitution scores at each aligned
+position between each pair of sequences. The basic method is described in the
+1995 paper by {\sl G. Casari, C. Sander} and {\sl A. Valencia} \footnote{{\sl
+Nature Structural Biology} (1995) {\bf 2}, 171-8.
+PMID: 7749921} and implemented at the SeqSpace server at the EBI.
+
+Jalview provides two different options for the PCA calculation: SeqSpace and
+Jalview mode. In SeqSpace mode, PCAs are computed using the identity matrix, and
+gaps are treated as 'the unknown residue' (this actually differs from the
+original SeqSpace paper, and will be adjusted in a future version of Jalview).
+In Jalview mode, PCAs are computed using the chosen score matrix - which for
+protein sequences, defaults to BLOSUM 62, and for nucleotides, is the
+DNA identity matrix that also treats Us and Ts as identical, to support analysis
+of both RNA and DNA alignments. The {\sl Change Parameters} allows the
+calculation method and score models to be changed.\footnote{See
+\url{http://www.jalview.org/help/html/calculations/pca.html}.}
+
+\subsubsection{The PCA Viewer}
+
+PCA analysis can be launched from the {\sl Calculate $\Rightarrow$ Principal
+Component Analysis} menu option. {\bf PCA requires a selection containing at
+least 4 sequences}. A window opens containing the PCA tool (Figure \ref{PCA}).
+Each sequence is represented by a small square, coloured by the background
+colour of the sequence ID label. The axes can be rotated by clicking and
+dragging the left mouse button and zoomed using the $\uparrow$ and $\downarrow$
+keys or the scroll wheel of the mouse (if available). A tool tip appears if the
+cursor is placed over a sequence. Sequences can be selected by clicking on them.
+[CTRL]-Click can be used to select multiple sequences.
+
+Labels will be shown for each sequence by toggling the {\sl View $\Rightarrow$
+Show Labels} menu option, and the plot background colour changed {\sl via} the
+{\sl View $\Rightarrow$ Background Colour..} dialog box. A graphical
+representation of the PCA plot can be exported as an EPS or PNG image {\sl via}
+the {\sl File $\Rightarrow$ Save As $\Rightarrow$ \ldots } submenu.
+
+\exercise{Principal Component Analysis}
+{\label{pcaex}
+\exstep{Load the alignment at
+\textsf{http://www.jalview.org/tutorial/alignment.fa}.}
+\exstep{Select the menu option {\sl Calculate $\Rightarrow$ Tree or PCA..}. in the alignment
+window and a dialogue box will open. Select the Principal Component Analysis option
+and then click the Calculate button.}
+\exstep{Move
+this window within the desktop so that the alignment and PCA viewer windows are visible.
+Try rotating the plot by clicking and dragging the mouse on the plot in the PCA window.
+Note that clicking on points in the plot will highlight the sequences on the
+alignment.}
+\exstep{Use the [ESC] key to deselect sequence selection.
+Select {\sl Calculate $\Rightarrow$ Tree or PCA..}. in the alignment window. In dialogue box select Neighbour
+Joining and in the drop-down list select BLOSUM62. Click the Calculate button
+and a tree window will open.}
+\exstep{Place the mouse cursor on the tree so that the
+tree partition divides the tree into a number of groups, each with a
+different (arbitrarily selected) colour.
+Note how the colour of the sequence ID label matches both the colour of
+the partitioned tree and the points in the PCA plot.}
+{\bf See the video at:
+\url{http://www.jalview.org/training/Training-Videos}.}
+}
+
+\begin{figure}[hbtp]
+\begin{center}
+\includegraphics[width=2in]{images/PCA1.pdf}
+\includegraphics[width=3in]{images/PCA3.pdf}
+\caption{{\bf PCA Analysis.} }
+\label{PCA}
+\end{center}
+\end{figure}
+
+
+
+\subsubsection{PCA Data Export}
+Although the PCA viewer supports export of the current view, the plots produced
+are rarely suitable for direct publication. The PCA viewer's {\sl File} menu
+includes a number of options for exporting the PCA matrix and transformed points
+as comma separated value (CSV) files. These files can be imported by tools such
+as {\bf R} or {\bf gnuplot} in order to graph the data.
+
+\section{Trees}
+\label{trees}
+Jalview can calculate and display trees, providing interactive tree-based
+grouping of sequences though a tree viewer. All trees are calculated {\sl via}
+the {\sl Calculate $\Rightarrow$ Calculate Tree $\Rightarrow$ \ldots} submenu.
+Trees can be calculated from distance matrices determined from \% identity or
+aggregate BLOSUM 62 score using either {\sl Average Distance} (UPGMA) or {\sl
+Neighbour Joining} algorithms. The input data for a tree is either the selected
+region or the whole alignment, excluding any hidden regions.
+
+On calculating a tree, a new window opens (Figure \ref{trees1}) which contains
+the tree. Various display settings can be found in the tree window {\sl View}
+menu, including font, scaling and label display options. The {\sl File
+$\Rightarrow$ Save As} submenu contains options for image and Newick file
+export. Newick format is a standard file format for trees which allows them to
+be exported to other programs. Jalview can also read in external trees in
+Newick format {\sl via} the {\sl File $\Rightarrow$ Load Associated Tree} menu
+option. Leaf names on imported trees will be matched to the associated alignment
+- unmatched leaves will still be displayed, and can be highlighted using the
+{\sl View $\Rightarrow$ Mark Unlinked Leaves} menu option.
+
+\exercise{Trees}
+{\label{treeex}
+{\sl Ensure that you have at least 1G memory available in Jalview.
+(Start with link:
+\href{http://www.jalview.org/services/launchApp?jvm-max-heap=1G}{http://www.jalview.org/services/launchApp?jvm-max-heap=1G},
+or in the table in the Development section of the Jalview web site
+(\href{http://www.jalview.org/development/development-builds}{http://www.jalview.org/development/development-builds}), go
+to ``latest official build'' row and in the ``Webstart'' column, click
+on ``2G''.)}
+
+\exstep{Open the alignment at
+\textsf{http://www.jalview.org/tutorial/alignment.fa}.}
+
+\exstep{Select {\sl Calculate $\Rightarrow$ Tree or PCA..}. in the alignment
+window and a dialogue box opens. In the tree section select Neighbour
+Joining, in the drop-down list select BLOSUM62 and click the Calculate
+button. A tree window will open.}
+
+\exstep{Click on the
+tree window, a cursor will appear. Note that placing this cursor divides the tree into a number of groups by colour.
+Place the cursor to give about 4 groups.}
+
+
+\exstep{In the tree window, select {\sl View $\Rightarrow$ Sort Alignment
+by Tree}. The sequences are reordered to match the order in the tree and groups
+ are formed implicitly. Alternatively in the alignment window, select
+{\sl Calculate $\Rightarrow$ Sort $\Rightarrow$ By Tree Order $\Rightarrow$
+ Neighbour Joining Tree using BLOSUM62 from...}.}
+
+\exstep{Select {\sl Calculate $\Rightarrow$ Tree or PCA..}. in the alignment
+window. In the dialogue box, select Average Distance and in the drop down
+list select BLOSUM62. Click the Calculate button and a new
+tree window will appear. The group colouring makes it easy to see the differences between the two
+trees calculated by the different methods.}
+
+\exstep{In the alignment window, select sequence 2 from
+column 60 to sequence 12 and column 123. Select {\sl Calculate $\Rightarrow$
+Tree or PCA..}. , in the dialogue box select Neighbour Joining and
+BLOSUM62, then click the Calculate button.
+ A tree will appear containing 11 sequences. It has been coloured
+ according to the already selected groups from the first tree and is calculated purely from the residues
+ in the selection.}
+
+Comparing the location of individual sequences between the three trees illustrates the importance of selecting appropriate regions of the
+alignment for the calculation of trees.
+
+{\bf See the video at:
+\url{http://www.jalview.org/training/Training-Videos}.}
+
+}