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One of the disadvantages of photodynamic therapy is impossibility to specify the method according to biological features of malignant tumor such as a degree of blood supply, accumulation of photosensibilizator in tumorous tissue, proliferative activity and etc. The authors aimed to develop a mode of individualization of endobronchial photodynamic therapy of central non-small cell carcinoma of lung and assessment of method efficacy. The suggested method is based on fluorescent diagnostics of degree of accumulation of photosensibilizator in timorous tissue and the rate of its expenditure in process of performing of photodynamic therapy. There was made a comparison of parameters of methods and results of photodynamic therapy in 2 randomized groups. Each group consisted of 45 patients. The research method was applied in the main group and the standard method was used in the comparison group. It was found that the research method allowed significant reduction of duration of irradiation compared with conventional method (at the average from 690±65sec to 470±45sec, p=0,02), though the treatment results were the same. The suggested method allowed separation of group of patients with absence of fluorescence of timorous tissue. Performance of photodynamic therapy is unreasonable for these patients.

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Hydraulic fracturing is essential for economic production in tight gas and shale gas reservoirs due to their low permeability nature. Slickwater fracturing has been successfully performed in shales and tight gas reservoirs using low viscosity fluid, usually water, with friction reducers. Slickwater fracturing has the advantage of reducing formation damage and generally being less expensive than conventional gel. Predicting which slickwater parameters are important to successful production and which are less important has been an important but unanswered question. This research uses multivariate statistical methods to discover whether production from the Jonah Field, Wyoming, and the Barnett Shale, Texas, can be predicted using slickwater parameters and whether these parameters can provide insight into the design and analysis parameters of the slickwater treatments. Factor, cluster, and multiple regression analysis show that production data from the sampled Barnett Shale and Jonah Field databases group separately from the slickwater parameters. Multiple regression, used to predict the EUR and the cumulative produced water from the slickwater parameters in the Barnett Shale, yielded best adjusted-R²’s of 34.7% and 25.3%, respectively. Multiple regression was also used to predict the EUR from the slickwater parameters in Jonah Field resulting in the best R² of 22.9%. Multiple regression analysis established a relationship with an adjusted R² of 93.0% between the fluid pumped and the fluid recovered from the Barnett Shale treatments. Multiple regression analysis also established that the amount of proppant used for Jonah Field hydraulic fracturing operations was calculated from the total fluid pumped and the net pay. This research provides a methodology to use multivariate statistics to analyze stimulation treatments. Additionally, it opens opportunities for the analysis of different fields with more data using multivariate statistics and can aid in improving designs in an operator's current field or in understanding previous designs in a newly acquired field. Finally, it also demonstrates how "no information" can be valuable in cutting costs on commodities purchased to stimulate a well when no benefit is seen from those additional purchases.