Impact and relationship of anterior commissure and time-dose factor on the local control of T1N0 glottic cancer treated by 6 MV photons

<p>Abstract</p> <p>Background</p> <p>To evaluate prognostic factors that may influence local control (LC) of T1N0 glottic cancer treated by primary radiotherapy (RT) with 6 MV photons.</p> <p>Methods</p> <p>We retrospectively reviewed the medical records of 433 consecutive patients with T1N0 glottic cancer treated between 1983 and 2005 by RT in our institution. All patients were treated with 6 MV photons. One hundred and seventy seven (41%) patients received 52.5 Gy in 23 fractions with 2.5 Gy/fraction, and 256 (59%) patients received 66 Gy in 33 fractions with 2 Gy/fraction.</p> <p>Results</p> <p>The median follow-up time was 10.5 years. The 10-year LC rates were 91% and 87% for T1a and T1b respectively. Multivariate analysis showed LC rate was adversely affected by poorly differentiated histology (Hazard Ratio [HR]: 7.5, <it>p </it>= 0.035); involvement of anterior commissure (HR: 2.34, <it>p </it>= 0.011); fraction size of 2.0 Gy (HR: 2.17, <it>p </it>= 0.035) and tumor biologically effective dose (BED) < 65 Gy₁₅(HR: 3.38, <it>p </it>= 0.017).</p> <p>Conclusions</p> <p>The negative impact of anterior commissure involvement could be overcome by delivering a higher tumor BED through using fraction size of > 2.0 Gy. We recommend that fraction size > 2.0 Gy should be utilized, for radiation schedules with five daily fractions each week.</p

Сравнительный анализ видового состава и структуры растительных сообществ с участием жостера слабительного Rhamnus cathartica в Беларуси и в регионах среднего запада США

   Описана история преднамеренной интродукции жостера слабительного (Rhamnus cathartica L.) в регионы Среднего Запада США. Изучен видовой состав и структура растительных сообществ, в которых произрастает R. сathartica – аборигенный для Беларуси и инвазионный в США вид. Проведено сравнение изучаемых параметров (полное флористическое описание пробных площадок, полевой перечет растений жостера, средняя высота, проективное покрытие сопутствующих видов) на двух пробных площадках на территории Беларуси и трех площадках на Среднем Западе США. Полученные данные подтвердили гипотезу повышения конкурентоспособности чужеродных видов во вторичном ареале (EICA). В американских популяциях, по сравнению с белорусскими, Rhamnus cathartica имеет более крупные размеры, более высокую семенную продуктивность, более высокую численность ювенильных особей и более высокую общую численность особей в популяциях вплоть до формирования монодоминантных зарослей. Внедрение жостера в естественные сообщества США снижает число видов травяного яруса в 8 раз. В качестве мер борьбы Арборетум Миннесоты начал облысение участков, на которые вторгся жостер, удаление на них малолетних особей (возраст от года до пяти лет), подсаживание местных древесных пород.   The history of intentional introduction of Rhamnus cathartica L. into the Midwestern regions of the USA is briefly described. The species abundance and structure of plant communities, in which Rhamnus cathartica, a native species for Belarus and invasive in the USA grows, has been studied. We compared the studied parameters (floristic description of the monitoring plots, field enumeration of Rhamnus cathartica individuals, average height, projective coverage of the accompanying herb species) at two permanent sample plots in Belarus and three permanent sample plots in the Midwestern regions of the USA. The data confirmed the hypothesis of increased competitiveness of non-native species in the secondary range (EICA). In American populations, compared to Belarusian populations, Rhamnus cathartica has larger sizes, higher seed production, higher number of juvenile individuals, and higher total number of individuals in the population up to the formation of single-species thickets. Invading Rhamnus cathartica into natural plant communities in the USA reduces the number of herbaceous species 8 times! As control measures, the Minnesota Arboretum has begun balding the areas invaded by Rhamnus cathartica, removing juvenile plants (one to five years old) and replanting native tree species.   Описана история преднамеренной интродукции жостера слабительного (Rhamnus cathartica L.) в регионы Среднего Запада США. Изучен видовой состав и структура растительных сообществ, в которых произрастает R. сathartica – аборигенный для Беларуси и инвазионный в США вид. Проведено сравнение изучаемых параметров (полное флористическое описание пробных площадок, полевой перечет растений жостера, средняя высота, проективное покрытие сопутствующих видов) на двух пробных площадках на территории Беларуси и трех площадках на Среднем Западе США. Полученные данные подтвердили гипотезу повышения конкурентоспособности чужеродных видов во вторичном ареале (EICA). В американских популяциях, по сравнению с белорусскими, Rhamnus cathartica имеет более крупные размеры, более высокую семенную продуктивность, более высокую численность ювенильных особей и более высокую общую численность особей в популяциях вплоть до формирования монодоминантных зарослей. Внедрение жостера в естественные сообщества США снижает число видов травяного яруса в 8 раз. В качестве мер борьбы Арборетум Миннесоты начал облысение участков, на которые вторгся жостер, удаление на них малолетних особей (возраст от года до пяти лет), подсаживание местных древесных пород

Evaluation of dose distribution for targets near inhomogeneities in photon beam radiation therapy

Purpose. The purpose of this work was to evaluate the accuracy of the dose calculated in the presence of inhomogeneities by the top performing algorithms employed by some commercially available modern treatment planning systems for the external photon beam radiotherapy. Materials and methods. A new Fluence Map Monte Carlo (FMMC) method that can serve as a benchmark for such evaluation under certain conditions for a given linear accelerator was developed and tested. Dose perturbation on the inhomogeneities composed of high, low and very low density materials was measured with film dosimeters and calculated with various algorithms. The algorithms included general purpose Monte Carlo and FMMC methods as well as the treatment planning dose calculation algorithms such as pencil beam kernel convolution, point kernel convolution, and superposition, which is the most accurate of the three. Results. The dosimetric comparison results for high density materials obtained by FMMC, superposition, and measurement revealed that the superposition overestimates (up to 16%) of the dose downstream of the inhomogeneity. A very low density medium such as an air cavity was found to have an overestimation (up to 20%) of the dose by the superposition algorithm. The dose in a lung (low density medium) equivalent material was found to be significantly overestimated when calculated with either point kernel (up to 20%) or pencil beam kernel (up to 40%) convolution algorithms. Conclusion. Based on these findings it is recommended that a particular attention should be given to the verification of a dose calculated for the treatment of tumors located in anatomical sites where inhomogeneities are predominant. In many cases a verification process can be successfully performed with the proposed FMMC method which is shown to have a good match with the measurements

Employee and Workforce Adaptation as a Result of Artificial Intelligence Deployment

Over the last decade (2010-2020), society saw many technological advancements that significantly impacted our lives and forever changed the world and its perception. Various algorithms are now embedded in our lives and have the ability to drive consumer behaviour. Artificial Intelligence has the advantages of rapidly digesting large volumes of data, exposing trends and patterns utilized for personalization and customization, and achieving the best possible outcome. However, society lacks the understanding of the price that will be paid for the adaptation to new business models. This research investigates the current trends and predictions for labour market changes and their societal impact and provides recommendations aimed at managing and adapting the workforce to the societal changes that resulted from the wide adoption of AI-powered tools. Additionally, this study describes the consequences of AI implementation and its effects on the labour market and outlines the threats of the significant increase in the unemployment rate using qualitative analysis of the secondary data. Recent publications from industry experts are reviewed, and predictions for the labour market are synthesized.</p

Preservation, in vitro regeneration and adaptation of Paulownia 9501 hybrid (Paulownia tomentosa × Paulownia fortunei)

The article presents the results of preservation, in vitro regeneration and adaptation of Paulownia (Paulownia) hybrid 9501 (Paulownia tomentosa × Paulownia fortunei). Several types of nutrient media with different phytohormones (cytokinins) were used for regeneration and preservation. It has been shown that the most suitable medium for the preservation of paulownia in the in vitro collection is with the addition of 15 g/l of sucrose, and for micropropagation, WPM with 1 mg/l of kinetin and WPM with 1 mg/l of 6-BAP. The influence on the course of adaptation of paulownia microseedlings of different types of substrates, as well as the preliminary treatment of microseedlings with the drug "Gesinar" was studied. It is shown that the best substrates for adaptation are vermiculite and agroperlite, and "Gesinar" does not affect the adaptation of microseedlings.В статье приведены результаты сохранения, регенерации в условиях in vitro и адаптации павловнии (Paulownia) гибрида 9501 (Paulownia tomentosa × Paulownia fortunei). Для регенерации и сохранения использовались несколько видов питательных сред с разными фитогормонами (цитокининами). Показано, что наиболее пригодной средой для сохранения павловнии в коллекции in vitro является с добавление 15 г/л сахарозы, а для микроклонального размножения – WPM с 1мг/л кинетина и WPM с 1мг/л 6-БАП. Изучено влияние на ход адаптации микросаженцев павловнии разных типов субстратов, а также предварительной обработки микросаженцев препаратом «Гесинар». Показано, что лучшими субстратами для адаптации является вермикулит и агроперлит, а «Гесинар» не влияет на адаптацию микросаженцев

Dosimetric verification of the anisotropic analytical algorithm in lung equivalent heterogeneities with and without bone equivalent heterogeneities

Purpose: In this study, the authors evaluated the accuracy of dose calculations performed by the convolution∕superposition based anisotropic analytical algorithm (AAA) in lung equivalent heterogeneities with and without bone equivalent heterogeneities