https://repositorio.ufu.br/handle/123456789/18792 Mon, 12 Oct 2026 02:46:25 GMT 2026-10-12T02:46:25Z https://repositorio.ufu.br/handle/123456789/50453 Title: Aplicação da nanotecnologia teranóstica e da segurança radiológica em Física em Médica: perspectiva abrangente sobre nanopartículas de carbono obtidas por síntese verde Fri, 07 Aug 2026 00:00:00 GMT https://repositorio.ufu.br/handle/123456789/50453 2026-08-07T00:00:00Z https://repositorio.ufu.br/handle/123456789/50445 Title: Revisão da literatura sobre a avaliação das doses e seus efeitos em exames de raios X e tomografia computadorizada abdominal em crianças Abstract: This study presents a literature review on the assessment of radiation doses from abdominal X-ray and computed tomography (CT) examinations in children, with an emphasis on their potential impacts on pediatric health and on optimization strategies aimed at reducing radiation exposure. The review showed that CT, although indispensable in cases requiring greater diagnostic detail, exposes pediatric patients to significantly higher radiation doses than conventional radiography. Given children’s greater vulnerability to ionizing radiation, practices based on the principles of justification and optimization are essential to mitigate potential risks. Technological advances, such as iterative reconstruction algorithms and automatic exposure control systems, have enabled substantial reductions in radiation exposure without compromising diagnostic image quality. In addition, the customization of protocols according to the child’s body size and age, together with educational initiatives such as “Image Gently,” has played a key role in raising awareness and training healthcare professionals. The findings of this study revealed variations in effective dose among the studies analyzed. For pediatric abdominal radiography, studies reported a mean effective dose of 34.6 µSv (0.0346 mSv). For pediatric abdominal CT examinations, a Brazilian study reported a mean effective dose of 4.35 mSv. In the international literature, typical values ranging from approximately 3.7 to 5.3 mSv have been reported for pediatric patients, depending mainly on age, patient size, and the imaging protocol employed. It is concluded that the implementation of optimized practices in pediatric radiology is essential to enhance patient safety while maintaining the diagnostic effectiveness of these examinations. Thu, 06 Aug 2026 00:00:00 GMT https://repositorio.ufu.br/handle/123456789/50445 2026-08-06T00:00:00Z https://repositorio.ufu.br/handle/123456789/50398 Title: Estudo de estabilidade da microbalança de cristal de quartzo para utilização em biossensores por transdução piezoelétrica aplicados na área da saúde Abstract: Piezoelectric biosensors allow the detection of compounds based on frequency variation, which reflects the mass deposited on the sensor. Among these devices, the Quartz Crystal Microbalance (QCM) stands out for its high sensitivity, being employed in the quantification of minute masses in various contexts. In the field of oncology, early cancer diagnosis can be decisive for therapeutic success, and tumor biomarkers present in body fluids constitute promising targets for potential detection by QCM. The present study aimed to develop and validate a QCM system, evaluating the stability and precision of three microcontrollers (Teensy 3.2, ESP32-WROOM, and Arduino Nano) at different fundamental frequencies, with a view to future application in biosensors for the healthcare field. The methodology consisted of assembling the resonant circuit, measuring the frequencies, and applying the Sauerbrey equation to calculate the limit of detection (LOD). The results showed a performance hierarchy, since the Teensy presented greater stability and precision, with an LOD of 5,42.10^(-11) g for the 40 MHz crystal; the ESP32 showed variations from 16 MHz onward and inefficiency at 24 MHz; the Arduino Nano proved unsuitable for crystals above 4 MHz due to clock limitations. Oscillations were observed in the inferred masses, attributed to noise inherent to the system, but with statistical reliability of 99% within the margin of three standard deviations. It is concluded that the project is feasible and that the Teensy is the most suitable for high-sensitivity applications. Improvements in programming are recommended, especially for the ESP32, as well as tests under thermal variation and biological assays for clinical validation. The system, once improved and further studied, demonstrates potential to assist in the detection of tumor biomarkers, which may contribute to the early diagnosis of cancer. Wed, 05 Aug 2026 00:00:00 GMT https://repositorio.ufu.br/handle/123456789/50398 2026-08-05T00:00:00Z https://repositorio.ufu.br/handle/123456789/50361 Title: Fundamentos e práticas da medicina nuclear: radiofármacos, controle de qualidade e radioproteção Wed, 05 Aug 2026 00:00:00 GMT https://repositorio.ufu.br/handle/123456789/50361 2026-08-05T00:00:00Z