Thin film growth and characterization of the electron- doped superconductor Sm̳2̳-x̳C̳ex̳CuO̳4̳-̳y

Sm̳2̳-x̳C̳ex̳CuO̳4̳-̳y belongs to a class of materials known as electron-doped superconductors (Ln̳2̳-x̳Mx̳CuO̳4̳-̳y;Ln = Pr, Nd, Sm, Eu; M = Ce, Th) and has a moderately high superconducting critical temperature, T̳c, of ̃ 20 K at optimal doping (x = 0.15). The trivalent rare earth site is doped with tetravalent Ce or Th; hence the name "electron-doped". Sm̳2̳-x̳C̳ex̳CuO̳4̳-̳y also exhibits a unique magnetic structure at low temperatures (T < 6 K) due to the antiferromagnetic ordering of the Sm³⁺ ions. In this study, thin films of the electron-doped superconductor Sm̳2̳-x̳C̳ex̳CuO̳4̳-̳y (SCCO) have been grown by pulsed laser deposition (PLD) for a cerium concentration range of x = 0.13 to x = 0.19. The films have been characterized through x-ray diffraction, electrical transport, and thermal transport measurements. A temperature versus cerium content (T-x) phase diagram has been constructed from the electrical transport measurements and yields a superconducting region similar to that of two of the other electron-doped superconductors Nd̳2̳-x̳C̳ex̳CuO̳4̳-̳y and Pr̳2̳- x̳C̳ex̳CuO̳4̳-̳y. Thermopower measurements were also performed on the samples and show a dramatic change from the underdoped region (x < 0.15) to the overdoped region (x < 0.15). Additionally, the standard Fisher-Fisher-Huse (FFH) vortex glass scaling model has been applied to the magnetoresistance data, as well as a modified scaling model (RRA), and the analysis yields values of the vortex glass melting temperature, T̳g, and critical exponent, v(z- 1). A magnetic field versus temperature (H-T) phase diagram has been constructed for the films with cerium content x >̲ 0.14, displaying the vortex glass melting lines. Magnetoresistance data taken as a function of angle, [theta], is also discussed in the context of the vortex glass scaling mode

Hendee's radiation therapy physics

The publication of this fourth edition, more than ten years on from the publication of Radiation Therapy Physics third edition, provides a comprehensive and valuable update to the educational offerings in this field. Led by a new team of highly esteemed authors, building on Dr Hendee’s tradition, Hendee’s Radiation Therapy Physics offers a succinctly written, fully modernised update. Radiation physics has undergone many changes in the past ten years: intensity-modulated radiation therapy (IMRT) has become a routine method of radiation treatment delivery, digital imaging has replaced film-screen imaging for localization and verification, image-guided radiation therapy (IGRT) is frequently used, in many centers proton therapy has become a viable mode of radiation therapy, new approaches have been introduced to radiation therapy quality assurance and safety that focus more on process analysis rather than specific performance testing, and the explosion in patient-and machine-related data has necessitated an increased awareness of the role of informatics in radiation therapy. As such, this edition reflects the huge advances made over the last ten years. This book: Provides state of the art content throughout Contains four brand new chapters; image-guided therapy, proton radiation therapy, radiation therapy informatics, and quality and safety improvement Fully revised and expanded imaging chapter discusses the increased role of digital imaging and computed tomography (CT) simulation The chapter on quality and safety contains content in support of new residency training requirements Includes problem and answer sets for self-test This edition is essential reading for radiation oncologists in training, students of medical physics, medical dosimetry, and anyone interested in radiation therapy physics, quality, and safety

A modified COMS plaque for iris melanoma

Melanoma of the iris is a rare condition compared to posterior ocular tumors and in this case report we presenta 51-year-old female patient with diffuse iris melanoma. Traditional COMS (Collaborative Ocular Melanoma Study)plaques are used at our institution for radiation therapy, so a novel modification of the traditional plaque was requiredto allow better conformance with placement on the cornea. The usual silastic insert was machined to dimensions incompliance with the cornea, placed without incident, and treatment delivered with excellent patient tolerance of themodified plaque