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[en] Radiation oncology in Slovakia is placed in precarious position. There is shortage of technology for modern conformal radiotherapy on one side. Paradoxically, technological advances have diverted the specialty away from traditional clinical care on the other side. While technology supplementation and health care infrastructure optimization could not be readily resolved, the focus and status of this field of medicine remains in hands of radiation oncologists. (author)
[en] This is a personal recollection of the early development of modern metamaterials as seen from the perspective of my GEC-Marconi team and collaborators, listed in the references Pendry et al 1996 Phys. Rev. Lett. 76 4773, Pendry et al 1998 J. Phys.: Condens. Matter. 10 4785. (paper)
[en] This book introduces nouns, articles, verbs, infinitives, particles, gerund, adjectives, adverbs, auxiliary verbs, prepositions, and conjunctions. It especially shows in detail nouns, verbs, prepositions, and other usages. It explains by comparing a few words such as customer and client, source and origin, height and altitude, top and summit, circle and ring, evidence and proof, allow and permit, generate and develop, tie and bind, mature and ripen, hang and suspend, treat, deal with and manipulate, jump, leap, vault, spring and hop, lift and raise, above, over, on and up, and below, under, beneath and down.
[en] This book contains origin of technology and development of civilization, national philosophy and ancient science and technology, Middle Age society and accumulation of science and technology, the era of the Renaissance and science and technology, development of science revolution and experimental science, technology and Mechanistic nature view of the manufacture time, science and evolution theory of the time of enlightenment idea, science and technology of the Industrial Revolution time, Korea's science and technology, modern technique and scientific approach, science and technology of the twenty-first century, and the role of science and technology in modern society.
[en] The meanwhile established generation of 16-slice CT systems enables routine sub-millimeter imaging at short breath-hold times. Clinical progress in the development of multidetector row CT (MDCT) technology beyond 16 slices can more likely be expected from further improvement in spatial and temporal resolution rather than from a mere increase in the speed of volume coverage. We present an evaluation of a recently introduced 64-slice CT system (SOMATOM Sensation 64, Siemens AG, Forchheim, Germany), which uses a periodic motion of the focal spot in longitudinal direction (z-flying focal spot) to double the number of simultaneously acquired slices. This technique acquires 64 overlapping 0.6 mm slices per rotation. The sampling scheme corresponds to that of a 64 x 0.3 mm detector, with the goal of improved longitudinal resolution and reduced spiral artifacts. After an introduction to the detector design, we discuss the basics of z-flying focal spot technology (z-Sharp trademark). We present phantom and specimen scans for performance evaluation. The measured full width at half maximum (FWHM) of the thinnest spiral slice is 0.65 mm. All spiral slice widths are almost independent of the pitch, with deviations of less than 0.1 mm from the nominal value. Using a high-resolution bar pattern phantom (CATPHAN, Phantom Laboratories, Salem, NY), the longitudinal resolution can be demonstrated to be up to 15 lp/cm at the isocenter independent of the pitch, corresponding to a bar diameter of 0.33 mm. Longitudinal resolution is only slightly degraded for off-center locations. At a distance of 100 mm from the isocenter, 14 lp/cm can be resolved in the z-direction corresponding to a bar diameter of 0.36 mm. Spiral ''windmill'' artifacts presenting as hyper- and hypodense structures around osseous edges are effectively reduced by the z-flying focal spot technique. Cardiac scanning benefits from the short gantry rotation time of 0.33 s, providing up to 83 ms temporal resolution with 2-segment ECG-gated reconstruction. (orig.)
[en] Nuclear science is considered as a big science and also the frontier in the 20"t"h century, it developed many big scientific facilities and many technique platforms (e.g., nuclear reactor, synchrotron radiation, accelerator, etc.) Nuclear Science and Technology (NST) provide us with many unique tools such as neutron beams, electron beams, gamma rays, alpha rays, beta rays, energetic particles, etc. These are efficient and essential probes for studying many technique and scientific issues in the fields of new materials, biological sciences, environmental sciences, life sciences, medical science, etc. Nano Science and Technology (NST) is a newly emerging multidisciplinary science and the frontier in the 21"s"t century, it is expected to dominate the technological revolution in diverse aspects of our life. It involves diverse fields such as nanomaterials, nanobiological sciences, environmental nanotechnology, nanomedicine, etc. nanotechnology was once considered as a futuristic science with applications several decades in the future and beyond. But, the rapid development of nanotechnology has broken this prediction. For example, diverse types of manufactured nanomaterials or nanostructures have been currently utilized in industrial products, semiconductors, electronics, stain-resistant clothing, ski wax, catalysts, other commodity products such as food, sunscreens, cosmetics, automobile parts, etc., to improve their performance of previous functions, or completely create novel functions. They will also be increasingly utilized in medicines for purposes of clinic therapy, diagnosis, and drug delivery. In the talk, we will discuss the possibility of NST-NST integration: how to apply the unique probes of advanced radiochemical and nuclear techniques in nanoscience and nanotechnology. (authors)