X-ray radiation hardness and influence on blinking in Si and CdSe quantum dots

We study the effect of X-ray irradiation on the photoluminescence (PL) efficiency and intermittency (blinking) of single Si/SiO2 and CdSe/CdZnS quantum dots (QDs). Our results show that the PL efficiency of Si nanocrystals is not significantly altered up to a cumulative fluence of 1020 photons/m2 (corresponding to $300 kGy of absorbed dose in SiO2), while CdSe particles become completely dark already after a 17 times lower fluence. In both types of QDs, the statistical nature of blinking ON-and OFF-times remains unaltered: mono-exponential for Si and power-law for CdSe QDs. However, the evolution of the blinking parameters with absorbed dose depends on the choice of material. On average, both ON-and OFF-time constants do not vary in Si nanocrystals, highlighting their radiation hardness. Instead, the ON-time exponent increases while the OFF-time exponent decreases with the increasing dose for CdSe

Aapplication of endoscopic ultrasound probes for the morphological diagnosis of peripheral lung tumors

The objective of this study was to evaluate the effectiveness of thin ultrasonic probes to search and verification of peripheral lung tumors. Materials and Methods: In 2016, the Chelyabinsk oncologic dispensary, outpatient phase, bronchoscopy was performed 323 using the ultrasonic probe of 20 MHz with a view to finding and verifying peripheral tumors. Results: Ultrasound imaging of tumors reached 168 (52%) of the total number of the bronchoscope with a mini ultrasound probes. Histological verification was obtained in 93 (55%) patients. Conclusion: The use of ultrasound probes as a supplement routine bronchoscopy for the purpose ultrasound imaging tumors and to obtain material for histological examination is a highly informative method in 55% of cases, it allows to verify the process of outpatient.Цель исследования - оценить эффективность применения тонких ультразвуковых зондов для поиска и верификации периферических новообразований лёгких. Материалы и методы. В 2016 году в Челябинском онкологическом диспансере, на амбулаторном этапе, было выполнено 323 бронхоскопии с применением ультразвуковых 20 МГц зондов с целью поиска и верификации периферических новообразований. Результаты. Ультразвуковая визуализация новообразований достигнута и произведена биопсия новообразования лёгкого у 168 (52%) пациентов. Гистологическая верификация получена у 93 (55%) больных. Заключение. Применение ультразвуковых зондов как дополнение рутинной бронхоскопии с целью визуализации новообразования и получения материала для гистологического исследования является высокоинформативным методом и в 55 % случаев позволяет верифицировать процесс на амбулаторном этапе