How to use PUNIAS

How to use PUNIAS?

PUNIAS can be used directly to analyze experimental data from a Agilent Technologies, Bruker / Veeco, Asylum Research, JPK, NT-MDT and Novascan facility.

In the case of data from an Asylum Research facility generated by using the Save to Memory option, this files are quite big since they can contain the information of several hundreds of trials, thus the data need first to be exported as an ASCII file by means of an export macro.

The first time you are launching the software the condition of use window is displayed:

You need to agree with the conditions of use after having read them in order to move further and be able to use the software.

If you accidentally click the "refuse" button, you won’t be able to use the software anymore. When you try to launch the software, the following window will be displayed:

In order to fix this problem, you will need to locate the configuration file for PUNIAS named "punias.ini" which is has been saved in the software folder and erase it.

This file contains all the configuration data the program needs (type of analysis, type of zoom, display of raw curves, display of markers…) and each time the user changes one of these configuration options by using the software this file is rewritten, saving the new options. Creating such a file has the advantage of saving the configurations the user likes so that he doesn’t need to, for example, choose the type of analysis he is used to using each time he starts up the software.

Once the configuration file has been erased you will again be able to go to thru the condition of use window.

After accepting the condition of use, the user interface will look like:

You need then to choose which kind of analysis you want to perform:

To start the analysis, a batch file can be generated and opened, the force curves opened directly, or the force curves opened through a drag & drop process.

PUNIAS will then open (one after the other) all the curves to be analyzed. After plotting the curve, as force versus extension or deformation, the computer determines the best possible baseline for the corresponding curve, and adds it to the graph. In the same way, the unfolding peaks or markers for the different calculations are determined by an algorithm and plotted on the graph. With all of these results being plotted on the graph along with the experimental curve, the user can very quickly visualize the results the computer finds, and validate them by saving the results and moving to the next file.

In case the user erroneously proceeds to the next file, he or she may go back (maximum 5 files) and re-analyze them by using the Home key. In case the user disagrees with the results of the algorithm, it is possible for the user to place a different baseline. The choice of a new baseline will discard all the unfolding peaks or markers found previously and generate a new set of results corresponding to the parameters characterized by the value of the new baseline. Once the user agrees with the setting of the baseline, it is then possible to add or discard peaks or modify the position of the markers. All the manual interactions with the software are done through the mouse and the keyboard using the arrow-keys and programmed keys.

A convenient way to obtain information on any part of the software is to use the contextual help:

The data is serialized immediately after each file is analyzed to avoid data loss.

A result file data file (extension .pic) is generated with the name of the file followed by different information depending on the type of analysis used.

All the data obtained at the end of the analysis can then be opened by different ASCII software to plot histograms and perform further analysis

Also, ASCII files can be created (if the Save ASCII Files option is activated) for each file opened to simplify the plotting of the files with spreadsheet software. These files are saved in a folder named PlotableData and contain four columns (piezo position for extension, extension curve, piezo position for retraction, retraction curve) with the data expressed in nanometers. And in the case of nano-indentation, there are additional ASCII files saved in a folder nanoIndent and containing four columns (deformation for extension and retraction in nanometer and force in pico Newton).

For any questions, suggestions, corrections, and requests for information please send a mail to: punias@free.fr.