diff --git a/apps/BioModelCalc/BioModelCmdLineParser.cpp b/apps/BioModelCalc/BioModelCmdLineParser.cpp
index 68261aa..30c65ef 100644
--- a/apps/BioModelCalc/BioModelCmdLineParser.cpp
+++ b/apps/BioModelCalc/BioModelCmdLineParser.cpp
@@ -1,122 +1,122 @@
 #include "BioModelCmdLineParser.h"
 
 namespace rttb
 {
 	namespace apps
 	{
 		namespace bioModelCalc
 		{
 
 			BioModelCmdLineParser::BioModelCmdLineParser(int argc, const char** argv, const std::string& name,
 				const std::string& version, bool virtuosSupport) :
 				CmdLineParserBase(name, version), _virtuosSupport(virtuosSupport)
 			{
 				addOption<std::string>(OPTION_DOSE_FILE, OPTION_GROUP_REQUIRED,
 				                       "The name of the dose file. Can be omitted if used as "
 				                       "positional argument (see above).", 'd', true);
 				addOption<std::string>(OPTION_OUTPUT_FILE, OPTION_GROUP_REQUIRED,
 				                       "The name of the output file. Can be omitted if used as "
 				                       "positional argument (see above).", 'o', true);
 				addPositionalOption(OPTION_DOSE_FILE, 1);
 				addPositionalOption(OPTION_OUTPUT_FILE, 1);
 				addOptionWithDefaultValue<std::string>(OPTION_MODEL, OPTION_GROUP_REQUIRED,
-				                                       "The used radiobiological model the dose should be analyzed with. Available models are:\n \"LQ\"",
+				                                       "The used radiobiological model the dose should be analyzed with. Available models are:\n \"LQ\", Formula: exp(-(alpha * D + beta * D^2/n))",
 				                                       "LQ", "LQ", 'm');
 				addOption<std::vector<double> >(OPTION_MODEL_PARAMETERS, OPTION_GROUP_OPTIONAL,
 				                                "The parameters for the radiobiological model.", 'p', false, true);
                 addOption<std::vector<std::string> >(OPTION_MODEL_PARAMETER_MAPS, OPTION_GROUP_OPTIONAL,
                     "The parameters maps as itk readable image files for the radiobiological model.", 'a', false, true);
 				addOptionWithDefaultValue<double>(OPTION_DOSE_SCALING, OPTION_GROUP_REQUIRED,
 				                                  "Dose scaling that should be applied.", 1.0, "1.0", 'e');
                 addOption<unsigned int>(OPTION_N_FRACTIONS, OPTION_GROUP_OPTIONAL,
-                    "Dose scaling that should be applied.", 'f');
+                    "The number of fractions (n in the formula).", 'f');
 				std::vector<std::string> defaultLoadingStyle;
 				defaultLoadingStyle.push_back("itk");
 
 				std::string doseLoadStyleDescription = "The loading style for the dose. Available styles are:\n"
 				                                       "\"dicom\": normal dicom dose\n"
 				                                       "\"itk\": use itk image loading\n"
 				                                       "\"helax\": load a helax dose (choosing this style, the dose path should only be a directory).";
 
 
 				if (_virtuosSupport)
 				{
 					doseLoadStyleDescription += "\n"
 					                            "\"virtuos\": load of a virtuos dose (This style is a multi argument. The second argument specifies the virtuos plan file, e.g. : \"--"
 					                            + OPTION_LOAD_STYLE + " virtuos myFavorite.pln\")";
 				}
 
 
 				addOptionWithDefaultValue<std::vector<std::string> >(OPTION_LOAD_STYLE, OPTION_GROUP_REQUIRED, doseLoadStyleDescription,
 				        defaultLoadingStyle, defaultLoadingStyle.at(0),
 				        't', true, true);
                 addOptionWithDefaultValue<std::vector<std::string> >(OPTION_LOAD_STYLE_PARAMETER_MAPS, OPTION_GROUP_OPTIONAL, doseLoadStyleDescription,
                     defaultLoadingStyle, defaultLoadingStyle.at(0),
                     'u', true, true);
 
 				parse(argc, argv);
 			}
 
 			void BioModelCmdLineParser::validateInput() const
 			{
 				std::string model = get<std::string>(OPTION_MODEL);
 
 				if (model != "LQ")
 				{
 					throw cmdlineparsing::InvalidConstraintException("Unknown model: " + model +
 					        ".\nPlease refer to the help for valid models.");
 				}
 				else
 				{
                     if (!isSet(OPTION_MODEL_PARAMETERS) && !isSet(OPTION_MODEL_PARAMETER_MAPS)){
                         throw cmdlineparsing::InvalidConstraintException("Either the model parameters or model parameter maps must be specified!");
                     }
 
                     if ((isSet(OPTION_MODEL_PARAMETERS) && get<std::vector<double> >(OPTION_MODEL_PARAMETERS).size() != 2) || (isSet(OPTION_MODEL_PARAMETER_MAPS) && get<std::vector<std::string> >(OPTION_MODEL_PARAMETER_MAPS).size() != 2))
 					{
 						throw cmdlineparsing::InvalidConstraintException("The LQ Model requires two parameters or parameter maps!");
 					}
 				}
 
 				std::vector<std::string> loadStyle = get<std::vector<std::string> >(OPTION_LOAD_STYLE);
 				std::string loadStyleAbbreviation = loadStyle.at(0);
 
 				if (loadStyleAbbreviation != "dicom" && (!_virtuosSupport || loadStyleAbbreviation != "virtuos")
 				    && loadStyleAbbreviation != "itk"
 				    && loadStyleAbbreviation != "helax")
 				{
 					throw cmdlineparsing::InvalidConstraintException("Unknown load style: " + loadStyleAbbreviation +
 					        ".\nPlease refer to the help for valid loading style settings.");
 				}
 				else if (_virtuosSupport && loadStyleAbbreviation == "virtuos")
 				{
 					if (loadStyle.size() < 2)
 					{
 						throw cmdlineparsing::InvalidConstraintException("Cannot load virtuos dose. Plan file is missing. Specify plan file as 2nd io style argument.");
 					}
 				}
 
 				double doseScaling = get<double>(OPTION_DOSE_SCALING);
 
 				if (doseScaling <= 0)
 				{
 					throw cmdlineparsing::InvalidConstraintException("Negative dose scaling is not allowed. Dose scaling has to be >0.");
 				}
 			}
 
 			void BioModelCmdLineParser::printHelp() const
 			{
 				cmdlineparsing::CmdLineParserBase::printHelp();
 				std::cout << "Example:" << std::endl << std::endl;
 				std::cout << m_programName <<
 				          " dose.mhd result.mhd -m LQ -p 0.2 0.02" <<
 				          std::endl << std::endl;
 				std::cout <<
 				          "This will calculate the Linear quadratic (LQ) BioModel from  \"dose.mhd\" and will write the result to \"result.mhd\". "
 				          "The alpha and beta parameters for the LQ model are 0.2 and 0.02, respectively."
 				          << std::endl;
 			}
 
 		}
 	}
 }