Purpose: The detective quantum efficiency (DQE) of indirect flat panel detectors (I-FPDs) is limited at higher x-ray energies (e.g., 100-140 kVp) by low absorption in their scintillating x-ray conversion layer. While increasing the thickness of the scintillator can improve its x-ray absorption efficiency, this approach is potentially limited by reduced spatial resolution and increased noise due to depth dependence in the scintillator's response to x rays. One strategy proposed to mitigate these deleterious effects is to irradiate the scintillator through the pixel sensor in a "back-irradiation" geometry. This work directly evaluates the impact of irradiation geometry on the inherent imaging performance of I-FPDs composed with columnar CsI:Tl and powder Gd 2 O 2 S:Tb (GOS) scintillators. Methods: A "bidirectional" FPD was constructed which allows scintillator samples to be interchangeably coupled with the detector's active matrix to compose an I-FPD. Radio-translucent windows in the detector's housing permit imaging in both "front-irradiation" (FI) and "back-irradiation" (BI) geometries. This test device was used to evaluate the impact of irradiation geometry on the x-ray sensitivity, modulation transfer function (MTF), noise power spectrum (NPS), and DQE of four I-FPDs composed using columnar CsI:Tl scintillators of varying thickness (600-1000 µm) and optical backing, and a Fast Back GOS screen. All experiments used an RQA9 x-ray beam. Results: Each I-FPD's x-ray sensitivity, MTF, and DQE was greater or equal in BI geometry than in FI. The I-FPD composed with CsI:Tl (1 mm) and an optically absorptive backing had the largest variation in sensitivity (17%) between FI and BI geometries. The detector composed with GOS had the largest improvement in limiting resolution (31%). Irradiation geometry had little impact on MTF (f) and DQE(f) measurements near zero frequency, however, the difference between FI and BI measurements generally increased with spatial frequency. The CsI:Tl scintillator with optically absorptive backing (1 mm) in BI geometry had the highest spatial resolution and DQE over all frequencies.Conclusions: Back irradiation may improve the inherent x-ray imaging performance of I-FPDs composed with CsI:Tl and GOS scintillators. This approach can be leveraged to improve tradeoffs between detector dose efficiency, spatial resolution and noise for higher energy x-ray imaging.

Direct conversion x-ray image detectors offer higher spatial resolution than their indirect counterparts. Organic-inorganic hybrid perovskites are among the most sensitive x-ray photoconductors for these detectors; however, high dark currents...

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The article considers the problem of development and competitiveness of the pharmaceutical industry companies of Ukraine as one of the leading knowledge-intensive and profitable industries in the world. The importance of development of the pharmaceutical market as one of the elements of ensuring the national security of the state is emphasized. The problem of innovation and technological development of Ukrainian economy sectors is defined as central in modern economic conditions. It is noted that it is necessary to use advanced concepts, methods and management tools in order to ensure the stable development of the pharmaceutical industry. The prospects of diversification of the product portfolio with innovative developments by attracting foreign investments are investigated. The possibility of the pharmaceutical industry turn to the international standards of development, research, production and product certification is analyzed, since the possibility of innovation development is the main factor of competitiveness of such high-tech industries as pharmaceutical. The financial and economic situation of Ukraine pharmaceutical industry in the context of the main financial indicators is investigated. Despite the systemic macroeconomic downturn in industrial production across the country, data was provided confirming a steady trend towards increasing sales of domestic pharmaceuticals enterprises. The results of the analysis and determination of the possibility of providing innovation development are interpreted on the example of Farmak JSC as it is one of the leading pharmaceutical industry companies. The economic data of the company, financial-economic analysis elements and determination of the financial stability degree with the help of the fuzzy logic apparatus were used for the research. The article confirmed the idea of the importance of investing in technological innovation. Directions of potential future researches are determined.