Light-tissue interactions for developing portable and wearable optoelectronic devices for sensing of tissue condition, diagnostics and treatment in Photodynamic therapy (PDT)

This thesis presents the development and in-vivo applications of wearable and portable devices for the investigation of light interaction with tissue involved in Photodynamic therapy (PDT) and during contraction of muscles. A hand-held device and a clinical method were developed for time course in-vivo imaging of the fluorescence of the photosensitizer Protoporphyrin IX (PpIX) in healthy and diseased skin with the aim to guide improvement of PDT protocols. The device was used in a small clinical study on 11 healthy volunteers and 13 patients diagnosed with non-melanoma skin cancer (NMSC). Two types of PpIX precursors were administered: Ameluz gel and Metvix® cream. The fluorescence was imaged with a 10 minute time step over three hours which was the recommended metabolism time before commencing PDT treatment at Ninewells Hospital, Dundee. The fluorescence time course was calculated by integrating the areas with the highest intensity. The fluorescence continued to grow in all subjects during the three hours. The time course varied between individuals. There was no statistical significance between either healthy volunteers or patients in Ameluz vs Metvix® groups; nor was there statistical difference between the three lesions groups (Actinic keratosis (AK) Ameluz vs AK Metvix® vs Basal cell carcinoma (BCC) Metvix®). The p-value was larger than 0.05 in a two sample t-test with unequal variances for all the groups. However, there was strong body site dependence between the head & neck compared to the lower leg & feet, or the trunk & hands body site groups (p-value<0.01). One of the possible explanations for this was temperature and vasculature variation in skin at different body sites: the temperature is higher and the vasculature structure is denser at the head and the neck compared to the lower leg or the trunk. The temperature was not measured during the study. So in order to support this hypothesis, typical skin temperatures at the lesion sites were taken from the IR thermal images of healthy skin available in literature. PpIX fluorescence had a positive correlation to temperature. If this hypothesis is true, it will be highly important to PDT treatment. Increasing the temperature could speed up the metabolism and reduce the waiting time before starting the treatment; ambient temperature should be taken into account for daylight PDT; cooling air as pain management should be administered with caution. Potential improvements for wearable PDT light sources were investigated by modelling light transport in skin for the current LED-based Ambulight PDT device, a commercial OLED for future devices and a directional OLED developed in the group. The optical models were implemented in commercial optical software (with intrinsic Monte Carlo ray tracing and Henyey-Greenstein scattering approximation) which was validated on diffuse reflectance and transmittance measurements using in-house made tissue phantoms. The modelling was applied to investigate the benefits from diffusive and forward scattering properties of skin on light transmission in treatment light sources. 1 mm thick skin can only compensate approximately 10% of non-uniform irradiance. It means that uniform illumination is crucial for the treatment light sources. Forward scattering in skin showed a 10% improved light transmission from a collimated emission compared to a wide angle Lambertian emission. However, depth-dependent transmission measurements of directional vs Lambertian emission from organic light emitting films (a nano-imprinted grating was fabricated to provide directional emission in one of the films), collimated vs diffused HeNe laser light through fresh porcine skin did not show the expected improvement. This could be explained by skin roughness which was previously found to change the optical properties and may also affect light coupling. The modelling was applied to guide an optical design of another wearable device – a muscle contraction sensor. Muscle is fibrous and because of that scatters light differently in different directions. The sensor detects the change in backscattered light in parallel and perpendicular directions with respect to muscle fibres. The sensor was implemented on a wearable bandage on fully flexible substrate with flexible OLED and organic photodiodes. The major advantages of organic optoelectronic sensing compared to conventional electromyography (EMG) sensors are the ability to distinguish two types of contractions (isotonic and isometric), insensitivity to electromagnetic interference and the absence of an immune response due to non-invasive electrode-free sensing. Optical modelling was performed to understand the operation of the sensor. A 3D anisotropic optical model of scattering in muscle was created by geometrical manipulations with the standard Henyey-Greenstein scattering volumes. The penetration depth from the Super Yellow OLED was found to be 20-25 mm; the optimal separation between the source and the detector was found to be 20 mm. This distance provided a still detectable signal along with the best discrimination between the two backscatterings. When a 2 mm thick layer of skin and a 2 mm thick layer of adipose tissue were added to the model, the signal was hugely diffused. The discrimination between the two backscatterings decreased by three orders of magnitude, the penetration depth in muscle was reduced, and the intensity of the signal dropped down but was still detectable. With 5 mm thick adipose tissue and 2 mm thick skin the signal was too diffused and interacted with very shallow layers of muscle which approached the limits of the optical sensing of muscle activity

Ошибкообнаруживающая способность квазиравновесного кода

У статті отримана кількісна оцінка здатності квазірівноважного коду виявляти помилки. Ця оцінка дозволяє більш точно визначити галузі ефективного використання коду і розробити способи адаптації його параметрів до кількості помилок у каналах передачі та кінцевих пристроях розподілених автоматизованих систем. Як таку оцінку застосовують ймовірність помилки, яка не виявляється. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/27994В статье получена количественная оценка ошибкообнаруживающей способности квазиравновесного кода, которая позволяет более точно определить области его эффективного использования и разработать способы адаптации параметров кода к количеству ошибок в каналах передачи и оконечных устройствах распределенных автоматизированных систем. В качестве такой оценки используется вероятность необнаруживаемой ошибки. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/27994In the paper the quantitative evaluation of error detection ability for a quasi-constant weight code is obtained. The evaluation makes it possible to determine more accurately fields of its effective application and to develop methods of error quantity adaptation of code parameters for transmission channels and terminal units of distributed automated system. In the capacity of such an evaluation the undetected error probability is used. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2799

Пристрій стиснення інформації

Пристрій стиснення інформації містить блок синхронізації, вхід якого підключений до інформаційного входу та входу синхронізації пристрою, вхід суматора одиниць підключений до інформаційного входу пристрою та виходу блока синхронізації, вихід суматора одиниць є першим виходом пристрою. До пристрою введений лічильник нулів, вхід якого приєднаний до інформаційного входу пристрою та виходу блока синхронізації, блок розрахунку біноміальних коефіцієнтів, на вхід якого заведені виходи суматора одиниць та лічильника нулів, блок розрахунку номерів, до входу якого підключений вихід блока розрахунку біноміальних коефіцієнтів та вихід блока синхронізації. Вихід блока розрахунку номерів є другим виходом пристрою. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/2888

Optimization of a company’s capital structure based on the criterion of minimizing the level of financial risk

In the context of growing economic uncertainty, capital structure optimization is becoming a critical tool for minimizing financial risks, providing companies with the necessary stability and adaptability in modern conditions. This paper aims to develop theoretical foundations for the existing capital structure optimization methods and elaborate an optimal capital structure formation strategy to ensure companies’ financial stability and flexibility in conditions of high financial uncertainty. The article offers a stabilization-flexible approach to optimizing companies’ capital structure in financial instability and crises, making it possible to ensure the companies’ financial stability while preserving their ability to adapt to a volatile environment quickly. The main idea of the approach is the balanced use of equity capital and long-term and short-term liabilities to finance various components of assets, which helps to minimize risks and increase the efficiency of financial management. A roadmap for the implementation of the stabilization-flexible approach to optimizing the capital structure has been formed, the basis of which is the construction of a logical chain of actions, including the definition of companies’ goals, the assessment of available financial resources and risks, and the development of financing strategies, their implementation, further control and monitoring of results. The study results can be helpful for financial managers, analysts, and investors seeking to improve the efficiency of capital management and reduce the impact of external and internal risks on the financial condition of companies

ADOÇÃO DE TECNOLOGIAS DE ENSINO INOVADORAS E DAS TIC NA INVESTIGAÇÃO: OPORTUNIDADES E OBSTÁCULOS

The relevance of the research is due to the rapid development of technologies, which transforms all aspects of modern society, particularly in the field of science and education. This research aims to systematise the modern theoretical and practical aspects of integrating innovative teaching technologies and ICT into research activities. The article aims to highlight the challenges and prospects of this process, substantiate the necessity of using the latest technologies in the scientific environment, and identify optimal strategies for their implementation. General scientific research methods are used in this work: analysis of literature sources, statistical analysis, and methods of systematisation and generalisation. SWOT analysis and expert assessments were used to identify the key challenges and prospects for developing ICT in the context of education and research activities. Based on the assessments of a group of experts, consisting of 14 postgraduate students, seven associate professors, and nine professors from the Igor Sikorsky Kyiv Polytechnic Institute, a correlation analysis was conducted using the JASP program with the "Classical Correlation" tool. Recommendations for integrating ICT into research activities based on the strength-based approach were formulated. The general trend in the technological development of Ukrainian scientific institutions is the active implementation of innovative teaching technologies and ICT, mainly to improve access to scientific data (63.3%) and promote international cooperation (66.7%). However, they face technical limitations and cybersecurity threats (43.3%). Thus, the challenges and prospects for integrating ICT into research activities are complementary factors that will stimulate further technological development of education and science when practical approaches are applied.A pertinência da investigação deve-se ao rápido desenvolvimento das tecnologias, que transforma todos os aspectos da sociedade moderna, nomeadamente no domínio da ciência e da educação. Esta investigação tem por objetivo sistematizar os aspectos teóricos e práticos modernos da integração de tecnologias de ensino inovadoras e das TIC nas actividades de investigação. O artigo visa destacar os desafios e as perspectivas deste processo, fundamentar a necessidade de utilizar as tecnologias mais recentes no ambiente científico e identificar estratégias óptimas para a sua implementação. Neste trabalho, são utilizados métodos gerais de investigação científica: análise de fontes bibliográficas, análise estatística e métodos de sistematização e generalização. A análise SWOT e as avaliações de peritos foram utilizadas para identificar os principais desafios e perspectivas de desenvolvimento das TIC no contexto das actividades de ensino e investigação. Com base nas avaliações de um grupo de peritos, constituído por 14 estudantes de pós-graduação, sete professores associados e nove professores do Instituto Politécnico Igor Sikorsky Kyiv, foi efectuada uma análise de correlação utilizando o programa JASP com a ferramenta "Correlação Clássica". Foram formuladas recomendações para a integração das TIC nas actividades de investigação com base na abordagem baseada na força. A tendência geral no desenvolvimento tecnológico das instituições científicas ucranianas é a implementação ativa de tecnologias de ensino inovadoras e das TIC, principalmente para melhorar o acesso aos dados científicos (63,3%) e promover a cooperação internacional (66,7%). No entanto, estas instituições enfrentam limitações técnicas e ameaças à cibersegurança (43,3%). Assim, os desafios e as perspectivas de integração das TIC nas actividades de investigação são factores complementares que estimularão um maior desenvolvimento tecnológico da educação e da ciência quando forem aplicadas abordagens práticas

Professional Culture of Future Specialists Within the Framework of Ukraine’s Sustainable Development Concept

In an increasingly globalized world, the imperative of sustainable development underscores the pivotal role of education and professional culture in nurturing sustainability-oriented mindsets and actions. This paper aims to explore the nexus between educational practices, professional culture, and sustainable development goals, particularly within the context of the Ukrainian national educational system and professional community. Through a comprehensive review of literature and empirical analysis, the study elucidates that the integration of sustainable development into educational curricula and professional ethos fosters heightened awareness and conscientious engagement with global environmental, economic, and social challenges. It underscores the significance of organizational cultures characterized by adaptability, innovation, and collaborative learning in advancing sustainable development agendas. However, effective implementation necessitates proactive strategies adaptable to evolving societal demands. The research advocates for the augmentation of interdisciplinary educational programs coupling theoretical insights with practical applications tailored to address real-world sustainable development challenges. Furthermore, it underscores the importance of incentivizing participation in sustainable development initiatives among educators and students alike, leveraging innovative learning technologies. Future research avenues should center on assessing the efficacy of such initiatives and devising methodologies for monitoring and evaluating their societal impact, thereby advancing sustainable development objectives

Засоби кодування і перетворення інформації в електронних системах

Об’єкт досліджень:розробка цифрових пристроїв для електронних систем. Предмет досліджень: завадостійкість цифрових пристроїв та захист з їх допомогою електронних систем від несанкціонованого доступу. Мета роботи:кодування інформації займає одне з важливих місць в процесі перетворення даних в різних електронних системах: автоматизованих системах управління, системах передачі і зберігання інформації. Метою кодування є підвищення ефективності роботи різних інформаційних систем за рахунок збільшення швидкості або надійності передачі для систем зв'язку, розширення можливостей обчислювальної обробки для систем машинної арифметики. Перспективним напрямом є розвиток біноміального кодування, заснованого на використанні біноміальних систем числення. Біноміальні коди, отримані на основі біноміальних систем числення, дозволяють підвищити завадостійкість цифрових пристроїв за рахунок їх структурної надлишковості, а також вирішують задачу захисту інформації від несанкціонованого доступу. У роботі досліджені біноміальні системи числення, на основі чого пропонується ідея використання біноміальних систем числення при розробці завадостійких біноміальних цифрових пристроїв, таких як лічильники імпульсів, регістри, дешифратори, перетворювачі кодів тощо, що дозволило покращити характеристики роботи сучасних цифрових систем, а також надало можливість побудувати нову концепцію їх роботи

Исследование желаемого образа семьи молодежи, проживающей в больших, средних и малых городах

Funding: EPSRC EP/J01771X, Royal Society Wolfson Research Merit AwardBackground Topical Photodynamic therapy (PDT) is an effective treatment for superficial non-melanoma skin cancers (NMSC) and dysplasia. During PDT light activates the photosensitiser (PpIX), metabolised from a topical pro-drug. A combination of PpIX, light and molecular oxygen results in inflammation and cell death. However, the outcomes of the treatment could be better. Insufficient biosynthesis of PpIX may be one of the causes of incomplete response or recurrence. Measuring surface fluorescence is usually employed as a means of studying PpIX formation. The aim of this work was to develop a device and a method for convenient fluorescence imaging in clinical settings to gather information on PpIX metabolism in healthy skin and NMSC with a view to improving PDT regimes. Methods A handheld fluorescence camera and a time course imaging method was developed and used in healthy volunteers and patients diagnosed with basal cell carcinoma (BCC) and actinic keratosis (AK). The photosensitiser (precursor) creams used were 5-aminolaevulinic acid (ALA; Ameluz®) and methyl aminolevulinate (MAL; Metvix®). Pain was assessed using a visual analogue score immediately after the PDT. Results Fluorescence due to PpIX increases over three hours incubation in healthy skin and in lesional BCC and AK. Distribution of PpIX fluorescence varies between the lesion types and between subjects. There was no significant correlation between PpIX fluorescence characteristics and pro-drug, diagnosis or pain experienced. However, there was a clear dependence on body site. Conclusion The device and the method developed can be used to assess the characteristics of PpIX fluorescence, quantitative analysis and time course. Our findings show that body site influences PpIX fluorescence which we suggest may be due to the difference in skin temperature at different body sites.PostprintPeer reviewe