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Sample records for wilhelm konrad roentgen

  1. Konrad Bajer

    NASA Astrophysics Data System (ADS)

    2014-10-01

    These Proceedings are dedicated to our co-editor Konrad Bajer, who carried the lion's share of the work involved until his sudden and untimely death from cancer on 29th August 2014. Konrad was one of the key Organisers of the program "Topological Dynamics in the Physical and Biological Sciences" held at the Isaac Newton Institute for Mathematical Sciences in Cambridge from July to December 2012. During that time, he was on leave from the University of Warsaw, and held a Visiting Fellow Commonership at Trinity College, Cambridge. He had particular responsibility for the satellite workshop Tangled Magnetic Fields in Astro- and Plasma Physics, held at ICMS, Edinburgh, in October 2012. Konrad graduated in Physics from the University of Warsaw in 1980, and took his PhD in Fluid Dynamics at DAMTP, Cambridge, 1984-89. He was active in EUROMECH, having been a principal organiser of the European Turbulence Conference (ETC13) in Warsaw 2011, and the meeting Turbulence: the Historical Perspective that followed it. He has been equally active in IUTAM; his distinction was recognised by his very recent election to the Congress Committee of IUTAM. Konrad's research interests were in magnetohydrodynamics and vortex dynamics in classical and quantum systems; also in problems of gasifcation, in which he played a coordinating role at the University of Warsaw. He impressed all with his exceptionally warm and friendly personality, and will be greatly missed in the whole scientifc community.

  2. Roentgen Stereophotogrammetry In Orthopedics

    NASA Astrophysics Data System (ADS)

    Selvik, Goran

    1983-07-01

    A system for roentgen stereophotogrammetry has been used in Lund, Sweden, since August 1972 and by August 1982 ten thousand stereo films have been evaluated using this method. Patient investigations started March 1973 and of the more than 500 patients investigated 300 have been referred by orthopedic surgeons. The skeletal parts investigated had been permanently marked with tantalum balls 0.5 or 0.8 mm in diameter. The causes for the investigation have been bone growth disorders in the Lower extremity (134 patients), spinal fusions (35 patients), high tibial osteotomies for gonarthrosis (21 patients) and endoprosthetic replacement of the knee (68 patients) or hip (42 patients) joint. By the roentgen stereophotogrammetric analysis (RSA), information on for instance the development of angular deformities and staple loosening in the leg, the healing process of the intended fusion in the spine or at the knee, and on the migration and stability of prosthetic components have been obtained. RSA is of value both for prognostic and followup purposes, and is versatile enough in proper setting to be used as a routine clinical investigation.

  3. Konrad Repository Facing its Construction

    SciTech Connect

    Kunze, V.

    2008-07-01

    According to the German Atomic Energy Act the Federation is responsible for the construction and operation of installations for the safekeeping and disposal of radioactive waste. This duty was assigned to the Federal Office for Radiation Protection (Bundesamt fuer Strahlenschutz - BfS). In 1982, the Federal Institute of Physics and Metrology (Physikalisch Technische Bundesanstalt - PTB) as the precursor of BfS applied for a license for the disposal of radioactive waste with negligible heat generation in the Konrad iron ore mine near Salzgitter at the Ministry for Environment of Lower Saxony. After 25 years of plan approval procedure and subsequent lawsuits the license is now valid and Konrad is waiting for construction. Facing this challenge BfS has established a project team to supervise the in-house and external activities to be done. It is intended to construct the Konrad repository within a preparation period of two years and a subsequent erection phase of four years. Thus, Konrad is planned to come into operation in 2013. In this paper the development of the plan approval procedure, the technical design of the planned repository, especially with regard to safety-related aspects, and the planning for the construction will be discussed. (authors)

  4. Spectrum Roentgen Gamma

    NASA Astrophysics Data System (ADS)

    Predehl, P.; Pavlinsky, M.

    2014-07-01

    Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in 2016 into a 6-month-period halo orbit around L2. The mission lifetime is planned to be more than seven years. While the first four years of the mission are devoted to an all sky survey, the rest of the mssion will be used for pointed observations. The payload consists of two X-ray telescopes, eROSITA and ART-XC. The eROSITA sky survey will be about 30 times more sensitive than ROSAT at energies between 0.5 and 2 keV, while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters out to redshifts z>1 in order to study the large scale structure in the universe and test cosmological models including Dark Energy. ART-XC's role is to extend the energy range of eROSITA alone, thereby doubling the effective area in the critical 4-7 keV range. The harder response of ART-XC also facilitates the x-ray detection of obscured AGN. Both instruments are currently in the flight model and calibration phase.

  5. Myocardial blood flow: Roentgen videodensitometry techniques

    NASA Technical Reports Server (NTRS)

    Smith, H. C.; Robb, R. A.; Wood, E. H.

    1975-01-01

    The current status of roentgen videodensitometric techniques that provide an objective assessment of blood flow at selected sites within the coronary circulation were described. Roentgen videodensitometry employs conventional radiopaque indicators, radiological equipment and coronary angiographic techniques. Roentgen videodensitometry techniques developed in the laboratory during the past nine years, and for the past three years were applied to analysis of angiograms in the clinical cardiac catheterization laboratory.

  6. Roentgen Stereophotogrammetry In Lund, Sweden

    NASA Astrophysics Data System (ADS)

    Selvik, Goran

    1980-07-01

    Since 1972 a system for analytic roentgen stereophotogrammetry utilizing tantalum indicators has been in use in Lund, Sweden, and by 1977 more than 3000 stereo roentgenograms have been evaluated with that system. Patient investigations started March 1973, and by March 1978, 200 patients have been marked with tantalum indicators and investigated for longer or shorter periods with the method. The reasons for the investigations have been very variable but growth disturbances, craniofacial anomalies, disorders of the spine and visceral tumours have dominated. The aim has been to evaluate the effects of medical and surgical treatments. The high technical reliability and versatility of the method has led to accurate and easy to interpret results with a distinct clinical significance.

  7. The scientific achievements of Klaus Wilhelm

    NASA Astrophysics Data System (ADS)

    Huber, Martin C. E.

    2002-06-01

    We summarise and illustrate the scientific achievements of Klaus Wilhelm, starting with his diploma thesis. We also touch on his science-policy work, which he did, first, as a staff member of ESRO and, later on, as a representative of the scientific community in ESA's Solar System Working Group. We then turn to Klaus Wilhelm's influence and impact as the Principal Investigator (PI) of the SUMER (Solar Ultraviolet Measurement of Emitted Radiation) experiment on the Solar and Heliospheric Observatory, SOHO. As a distinguished collaborator of the PI in an earlier groundbreaking space experiment, namely the Halley Multicolour Camera (HMC) on ESA's Giotto probe, he was predestined to become a leading figure in the SOHO Science Working Team (SWT). The organisation of his experiment team was impeccable and he always focused his mind on the scientific and technical aims of SUMER. Personal or political issues never distracted him. Klaus Wilhelm was instrumental in achieving a reliable radiometric calibration that was traceable to a primary radiative laboratory standard. SUMER was the UV experiment on SOHO with the best, most comprehensive laboratory calibration and, thanks to integrity of design and a careful choice of materials, SUMER had a remarkably stable responsivity in orbit. Thus, Klaus Wilhelm as SUMER PI, had a decisive influence on two of the most important improvements in vacuum-ultraviolet solar spectroscopy that came with SOHO: cleanliness - in particular, with respect to condensable matter - and radiometric accuracy. Klaus Wilhelm is a scientist with sound principles. His enthusiasm, his pleasant personality, his urge to rapidly and thoroughly resolve problems when they arise and his continuous search for knowledge have led to the success of SOHO's SUMER experiment, and of this career as a scientist.

  8. Roentgen signs in diagnostic imaging. Second edition

    SciTech Connect

    Meschan, I. Farrer-Meschan, R.M. )

    1987-01-01

    This book contains 13 chapters. Some of the titles are: Radiology of the diaphragm, pleura, thoracic cage, and upper air passages; Radiology of the breasts; Radiology of nodular lesions of the lung parenchyma; Roentgen signs of abnormalities in the lung: and overview; and Special examination of the larynx.

  9. Roentgen stereophotogrammetry for analysis of cranial growth

    SciTech Connect

    Selvik, G.; Alberius, P.; Fahlman, M.

    1986-04-01

    A system of roentgen stereophotogrammetric analysis (RSA) has been developed and its value in studies of cranial growth in both man and the experimental animal (rabbit) has been delineated. This method is based on measurements from metal bone marker images on roentgenograms. Two roentgen tubes simultaneously expose the object, which is placed in one of two types of calibration cages. The object position does not need to be identical from one examination to the next. The cage, holding indicators of predetermined internal positions (in two or four planes), defines a laboratory coordinate system. Two-dimensional image coordinates are obtained by means of a highly accurate cartographic instrument. By computer reconstruction of the x-ray beams through the markers, 3-D object coordinates are calculated. For subsequent analysis of growth processes, extensive software is necessary. To control intrasegmental stability (routinely performed at each examination), a minimum of two markers is required, whereas three markers are needed in each skeletal segment for kinematic analysis using the rigid-body concept. Careful planning of marker placement before implantation minimizes implant loss and instability that otherwise might be a problem. Complications other than bone marker loosening have been nonexistent. The technical accuracy is high. Consequently, roentgen stereophotogrammetry, with the aid of metallic implants, is a superior means to obtain biometric information on cranial growth with relative ease.

  10. Wilhelm Dilthey forerunner of humanist social thought.

    PubMed

    Brown, R H

    Humanist sociology is as a meadow in the forest of positivist science. Much of this space was cleared by Wilhelm Dilthey, not only through his attack on the fundamental assumptions of positivism, but also through his formulation of a critical method by which the works of free human consciousness could be understood. The first tenet of positivism is that the world is made up of "out there" objectively knowable "facts". Dilthey undercut this notion by asserting that the subject matter of the human studies was not mere "facts" of nature, but rather objectified expressions and the human mind. The second central assumption of positivism is that these "facts" are explainable or determined by general casual laws. In contrast, Dilthey asserted that, while we can explain the natural world, human action must be understood through an interpretive rather than a casual logic. In demonstrating and specifically describing such an interpretive procedure, Dilthey provided an epistemiological and methodological grounding for a humanistic science of man. PMID:799624

  11. Wilhelm Weinberg's early contribution to segregation analysis.

    PubMed

    Stark, Alan; Seneta, Eugene

    2013-09-01

    Wilhelm Weinberg (1862-1937) is a largely forgotten pioneer of human and medical genetics. His name is linked with that of the English mathematician G. H. Hardy in the Hardy-Weinberg law, pervasive in textbooks on population genetics since it expresses stability over generations of zygote frequencies AA, Aa, aa under random mating. One of Weinberg's signal contributions, in an article whose centenary we celebrate, was to verify that Mendel's segregation law still held in the setting of human heredity, contrary to the then-prevailing view of William Bateson (1861-1926), the leading Mendelian geneticist of the time. Specifically, Weinberg verified that the proportion of recessive offspring genotypes aa in human parental crossings Aa × Aa (that is, the segregation ratio for such a setting) was indeed p=1/4. We focus in a nontechnical way on his procedure, called the simple sib method, and on the heated controversy with Felix Bernstein (1878-1956) in the 1920s and 1930s over work stimulated by Weinberg's article. PMID:24018765

  12. Sources of Wilhelm Johannsen's genotype theory.

    PubMed

    Roll-Hansen, Nils

    2009-01-01

    This paper describes the historical background and early formation of Wilhelm Johannsen's distinction between genotype and phenotype. It is argued that contrary to a widely accepted interpretation (For instance, W. Provine, 1971. The Origins of Theoretical Population Genetics. Chicago: The University of Chicago Press; Mayr, 1973; F. B. Churchill, 1974. Journal of the History of Biology 7: 5-30; E. Mayr, 1982. The Growth of Biological Thought, Cambridge: Harvard University Press; J. Sapp, 2003. Genesis. The Evolution of Biology. New York: Oxford University Press) his concepts referred primarily to properties of individual organisms and not to statistical averages. Johannsen's concept of genotype was derived from the idea of species in the tradition of biological systematics from Linnaeus to de Vries: An individual belonged to a group - species, subspecies, elementary species - by representing a certain underlying type (S. Müller-Wille and V. Orel, 2007. Annals of Science 64: 171-215). Johannsen sharpened this idea theoretically in the light of recent biological discoveries, not least those of cytology. He tested and confirmed it experimentally combining the methods of biometry, as developed by Francis Galton, with the individual selection method and pedigree analysis, as developed for instance by Louis Vilmorin. The term "genotype" was introduced in W. Johannsen's 1909 (Elemente der Exakten Erblichkeitslehre. Jena: Gustav Fischer) treatise, but the idea of a stable underlying biological "type" distinct from observable properties was the core idea of his classical bean selection experiment published 6 years earlier (W. Johannsen, 1903. Ueber Erblichkeit in Populationen und reinen Linien. Eine Beitrag zur Beleuchtung schwebender Selektionsfragen, Jena: Gustav Fischer, pp. 58-59). The individual ontological foundation of population analysis was a self-evident presupposition in Johannsen's studies of heredity in populations from their start in the early 1890s till his death in 1927. The claim that there was a "substantial but cautious modification of Johannsen's phenotype-genotype distinction" (Churchill, 1974, p. 24) from a statistical to an individual ontological perspective derives from a misreading of the 1903 and 1909 texts. The immediate purpose of this paper is to correct this reading of the 1903 monograph by showing how its problems and results grow out of Johannsen's earlier work in heredity and plant breeding. Johannsen presented his famous selection experiment as the culmination of a line of criticism of orthodox Darwinism by William Bateson, Hugo de Vries, and others (Johannsen, 1903). They had argued that evolution is based on stepwise rather than continuous change in heredity. Johannsen's paradigmatic experiment showed how stepwise variation in heredity could be operationally distinguished from the observable, continuous morphological variation. To test Galton's law of partial regression, Johannsen deliberately chose pure lines of self-fertilizing plants, a pure line being the descendants in successive generations of one single individual. Such a population could be assumed to be highly homogeneous with respect to hereditary type, and Johannsen found that selection produced no change in this type. Galton, he explained, had experimented with populations composed of a number of stable hereditary types. The partial regression which Galton found was simply an effect of selection between types, increasing the proportion of some types at the expense of others. PMID:20027784

  13. The Meaning of Disfigurement in Wilhelm Hauff's "Dwarf Nose."

    ERIC Educational Resources Information Center

    Blamires, David

    2002-01-01

    Notes that Wilhelm Hauff's fairy tale "Dwarf Nose" tells of a boy who is turned into a squirrel for seven years, then regains human form as a dwarf with a long nose before finally achieving normal adult proportions. Discusses how the story includes details that suggest a sexual interpretation. (SG)

  14. Wilhelm von Humboldt's Idea of "Bildung" and Education.

    ERIC Educational Resources Information Center

    Stubbs, Elsina

    The importance of Wilhelm von Humboldt's work in educational philosophy is little known outside of Germany and even there he is more often criticized than praised. This is unfortunate because his contributions to education and other areas had an important impact on other philosophers of his period and are well worth considering today. In his main…

  15. Roentgen therapy for infections: an historical review.

    PubMed Central

    Berk, L. B.; Hodes, P. J.

    1991-01-01

    Radiation was used extensively for the treatment of all types of infections before the advent of antibiotics. Although this mode of therapy is now in disrepute, radiation therapists of that era were firm believers in the ability of radiation to cure infections. A review of the literature suggests, but certainly does not prove, that low-dose local radiation, in the range of 75 to 300 roentgens, is an effective treatment modality for a wide variety of infections. Two then-prevailing rationales held that the effect was due either to radiation damage to the immune cells, causing stimulation of the immune response, or to the increase in local inflammation with resultant increased blood flow. Modern research has been limited but provides support for both arguments. Although there are no present indications for using radiation as therapy for infectious disease, a reasonable argument can be made from the available data that radiation is effective for the treatment of localized infections. The mechanisms of low-dose radiation as a treatment for infections remain unclear. The known and probable long-term sequelae of low-dose local irradiation preclude its common use for this condition. Nevertheless, it is hoped that this review will stimulate investigations into this relatively unexplored area of radiobiology. PMID:1750226

  16. Waldemar Wilhelm: father of oral and maxillofacial surgery in Colombia.

    PubMed

    Castro-Núñez, Jaime

    2011-01-01

    Waldemar Wilhelm (1913-1994) was honored by the Asociación Colombiana de Cirugía Oral y Maxilofacial (Colombian Association of Oral and Maxillofacial Surgery) as the Father of Oral and Maxillofacial Surgery in Colombia. Born in Karlsruhe, Germany, Wilhelm graduated as a dentist from Johann Wolfgang Goethe University in 1936. He emigrated shortly thereafter to Colombia, receiving his dental license there in 1943. He completed his oral and maxillofacial surgery training at Nordwestdeutsche Kieferklinic, under the tutelage of Prof. Dr. Dr. Karl Schuchardt in Hamburg. In 1950, he settled in Bogotá, where he joined the Universidad Nacional School of Dentistry, opened Colombia's first oral and maxillofacial surgery department at Hospital San José, and trained the first maxillofacial surgeons in Colombia in 1958. PMID:22372189

  17. Die Mondkarte von Wilhelm Beer und Johann Heinrich Mdler.

    NASA Astrophysics Data System (ADS)

    Maurer, A.

    Wilhelm Beer's and Johann Heinrich Mdler's research of the Moon's topography and above all their 1836 published map of the moon are even today of historical interest. In order to facilitate the access to relevant documents also for further research work, a systematic collection of bilbiographical sources and references to preserved or lost original drawings, as well as of information about the whereabouts of published moon map examples is compiled here.

  18. The Construction of the Konrad Repository - Status and Perspective - 13034

    SciTech Connect

    Kunze, V.

    2013-07-01

    Due to the Atomic Energy Act of Germany the Federation is responsible for the construction and operation of installations for the safekeeping and disposal of radioactive waste. The Federal Office for Radiation Protection (Bundesamt fuer Strahlenschutz - BfS) is assigned with this duty. In 1982 the abandoned iron ore mine Konrad near Salzgitter (Federal State of Lower Saxony) was proposed as a repository for low and intermediate level radioactive waste with negligible heat generation. After 20 years of plan approval procedure the license was granted by the Ministry for Environment of Lower Saxony in May 2002. This decision was finally confirmed by the Federal Administrative Court in March 2007. The construction has started, but former assumptions about the beginning of waste emplacement tuned out to be too optimistic. In the course of the preparatory work and the implementation planning it turned out that many changes need to be done. As a matter of fact most of the documents and planning originate from the 1990's and need to be revised because from that time on until now no adaptation was appropriate. The necessity to apply the state-of-the-art technology and other legal implications give rise to further changes and new licensing procedures, especially building licenses. Furthermore, the license from 2002 also includes a lot of collateral clauses that need to be fulfilled before radioactive waste can be emplaced. With this in mind, the time frame for the construction of the Konrad repository was revised in 2010. As a result, the completion of the erection before 2019 does not seem to be realistic. (authors)

  19. Wilhelm Tempel and his 10.8-cm Steinheil Telescope

    NASA Astrophysics Data System (ADS)

    Bianchi, Simone; Gasperini, Antonella; Galli, Daniele; Palla, Francesco; Brenni, Paolo; Giatti, Anna

    2010-03-01

    The German astronomer Ernst Wilhelm Leberecht Tempel (1821-1889) owed most of his successes to a 10.8-cm Steinheil refractor, which he bought in 1858. A lithographer, without an academic foundation, but with a strong passion for astronomy, Tempel had sharp eyesight and a talent for drawing, and he discovered with his telescope many celestial objects, including asteroids, comets (most notably, 9 P/Tempel 1) and the Merope Nebula in the Pleiades. Tempel carried his telescope with him throughout his moves in France and Italy. The telescope is now conserved in Florence, at the Arcetri Astrophysical Observatory, where Tempel was astronomer from 1875 until the end of his life. Using unpublished material from the Arcetri Historical Archive, as well as documents from other archives and published material, we trace the history of the telescope and its use during and after Tempel's life, and describe its recent rediscovery and status.

  20. Wilhelm Troll (1897 - 1978): idealistic morphology, physics, and phylogenetics.

    PubMed

    Rieppel, Olivier

    2011-01-01

    Idealistic morphology as articulated by the botanist Wilhelm Troll, the main target of the critique voiced by the early phylogeneticists, was firmly embedded in its contemporary scientific, cultural, and political context. Troll appealed to theoretical developments in contemporary physics in support of his research program. He understood burgeoning quantum mechanics not only to threaten the unity of physics, but also the validity of the principle of causality. Troll used this insight in support of his claim of a dualism in biology, relegating the causal-analytical approach to physiology, while rejuvenating the Goethean paradigm in comparative morphology. This embedded idealistic morphology in the völkisch tradition that characterized German culture during the Weimar Republic and its aftermath. In contrast, the contemporary phylogeneticists anchored their research program in the rise of logical positivism and in Darwin's principle of natural selection. This, in turn, brought phylogenetic systematists of the late 1930s and early 1940s into the orbit of national-socialist racial theory and eugenics. In conclusion, the early debate between idealistic morphologists and phylogenetic systematists was not only ideologically tainted, but also implied a philosophical impasse that is best characterized as a conflict between the Goethean and Newtonian paradigm of natural science. PMID:22696827

  1. Wilhelm Weinberg’s Early Contribution to Segregation Analysis

    PubMed Central

    Stark, Alan; Seneta, Eugene

    2013-01-01

    Wilhelm Weinberg (1862–1937) is a largely forgotten pioneer of human and medical genetics. His name is linked with that of the English mathematician G. H. Hardy in the Hardy–Weinberg law, pervasive in textbooks on population genetics since it expresses stability over generations of zygote frequencies AA, Aa, aa under random mating. One of Weinberg’s signal contributions, in an article whose centenary we celebrate, was to verify that Mendel’s segregation law still held in the setting of human heredity, contrary to the then-prevailing view of William Bateson (1861–1926), the leading Mendelian geneticist of the time. Specifically, Weinberg verified that the proportion of recessive offspring genotypes aa in human parental crossings Aa × Aa (that is, the segregation ratio for such a setting) was indeed p=14. We focus in a nontechnical way on his procedure, called the simple sib method, and on the heated controversy with Felix Bernstein (1878–1956) in the 1920s and 1930s over work stimulated by Weinberg’s article. PMID:24018765

  2. Trapeziometacarpal joint implants can be evaluated by roentgen stereophotogrammetric analysis.

    PubMed

    Hansen, T B; Larsen, K; Bjergelund, L; Stilling, M

    2010-07-01

    Both marker-based roentgen stereophotogrammetric analysis (RSA) and model-based RSA have been helpful evaluation tools in hip and knee arthroplasty. The purpose of this study was to test both model-based and marker-based RSA in the evaluation of total joint prostheses of the trapeziometacarpal joint. In a phantom study, the precision of marker-based RSA was tested with a cemented polyethylene cup and compared with the precision of model-based RSA in an uncemented Elektra screw cup. The precision of model-based RSA of the metacarpal stem was tested using an uncemented Elektra metacarpal stem. In a clinical study 11 patients had double stereo radiographs followed by RSA analysis. The precision of translation in both marker-based and model-based RSA was sufficient for clinical use, but rotation cannot be estimated with sufficient precision. PMID:20181771

  3. Stranded in Vienna: Wilhelm Ebert (1871-1916) (German Title: Gestrandet in Wien: Wilhelm Ebert (1871-1916))

    NASA Astrophysics Data System (ADS)

    Schnell, Anneliese

    2011-08-01

    Wilhelm Ebert, born 1871 in Leipzig, did study astronomy for a short time in Geneva and afterwards in Munich where he finished his PhD. He spent most of his scientific life in France, working on problems of latitude determination and celestial mechanics, mostly at the Bureau des Longitudes in Paris. He was member of the Astronomische Gesellschaft. Probably he used some of the regular meetings of the AG to introduce his work to German astronomers - for a rather short time he worked at the observatories of Kiel, Straßburg and Greifswald. In Greifswald he qualified for giving university lectures and he started to collect astronomical instruments to establish an observatory. M. Loewy, at that time director of Paris observatory, asked him to come back to France, first he had a position at Nice Observatory and shortly afterwards in Paris again. In 1909 he decided to live in Vienna, once more he applied for the qualification of giving university lectures; this time the procedure was easy going. He announced quite a lot of courses but nobody knows if they really took place. From February 1915 until his death in November 1916 he stayed in a psychiatric hospital in Vienna suffering from a disease which was uncurable at that time. His wife tried to get some information about his death in 1937. Already at that time he was unknown to the members of Vienna Observatory.

  4. The lunar map by Wilhelm Beer and Johann Heinrich Mdler. (German Title: Die Mondkarte von Wilhelm Beer und Johann Heinrich Mdler)

    NASA Astrophysics Data System (ADS)

    Maurer, Andreas

    Wilhelm Beer's and Johann Heinrich Mdler's research of the topography of the moon and above all their 1836 published map of the moon are even today of historical interest. In order to facilitate the access to relevant documents also for further research work, a systematic collection of bibliographical sources and references to preserved or lost original drawings, as well as of information about the whereabouts of published moon map examples is compiled here.

  5. [Roentgen rays in the Spanish-American War].

    PubMed

    Bonmatí, J

    2006-01-01

    The Spanish-American War broke out in 1898, only 28 months after Roentgen discovered some mysterious rays. It was a war of short duration in which bloody battles with numerous casualties took place in Cuba within a few days a period. In this conflict North American military physicians employed the recently discovered and poorly known rays in the study of gunshot wounds. The early use of x-rays in the first important war after their discovery reveals a great sensitivity and attention of is highest military command and an exemplary preparation of its Medical Camps to use potentially efficient modern means to achieve their goals. The use of x-rays in this brief but key war conclusively demonstrated the usefulness of this technique in the management of war wounds, brought about a revolutionary change in the methods and criteria of diagnosis and treatment, and represented an enormous benefit for this type of patient. The knowledge acquired was applied in medical and surgical environments throughout the world and profoundly transformed healthcare. This rigorous and opportune experience was a transcendental scientific advance in the field of medicine, is a landmark in the history of radiology and deserves to be well known and recognized by all, especially by those who later on made of these rays their specialty. PMID:17058372

  6. Perfecting the Individual: Wilhelm von Humboldt's Concept of Anthropology, "Bildung" and Mimesis

    ERIC Educational Resources Information Center

    Wulf, Christoph

    2003-01-01

    In the works of Wilhelm von Humboldt education took on a new quality, focusing firmly on the importance of the individual. "Bildung" was to become the principal task with a view to preparing the individual for the requirements of future life. In this article, the author investigates two aspects relating to the "Bildung" of the individual. First,…

  7. Wilhelm von Humboldt and the "Orient": On Edward W. Said's Remarks on Humboldt's Orientalist Studies

    ERIC Educational Resources Information Center

    Messling, Markus

    2008-01-01

    From an epistemological perspective, Wilhelm von Humboldt's studies on the Oriental and East Asian languages and writing systems (Egyptian hieroglyphs, Sanskrit, Chinese, Polynesian) raise the question of his position in the Orientalist discourse of his time. Said [Said, E.W., 1978. "Orientalism. Western Conceptions of the Orient, fourth ed."…

  8. [Wilhelm Liepmann (1878-1939)--the fate of a gynecologist between the Kaiser Reich and Fascism].

    PubMed

    Schneck, P

    1984-01-01

    The paper gives a bioergographical survey on the German obstetrician and gynaecologist Wilhelm Liepmann. He was Ass. Professor at the Berlin university. Later he became director of the German Women-Institute, which was founded by the Hauptverband der Krankenkassen. In 1933 Liepmann had to emigrate to Turkey, where he got the chair of gynaecology at the university of Istanbul. PMID:6388195

  9. Lumbar orthosis with unilateral hip immobilization. Effect on intervertebral mobility determined by roentgen stereophotogrammetric analysis.

    PubMed

    Axelsson, P; Johnsson, R; Strömqvist, B

    1993-06-01

    To determine the additional stabilizing effect of unilateral hip fixation on external lumbar supports, nine patients with a posterolateral lumbosacral fusion without internal fixation were examined by roentgen stereophotogrammetric analysis. The roentgen stereophotogrammetric analysis was performed with the patients in supine and erect positions 1 month after surgery, that is, before fusion consolidation. Each patient was examined without lumbar support and with a molded, rigid thoracolumbosacral orthosis with extension to one thigh, thus immobilizing one hip. The additional hip immobilization had no consistent or significant stabilizing effect on the sagittal, vertical, or transverse intervertebral translations in the lower lumbar spine. This study using roentgen stereophotogrammetric analysis gave no support for including hip immobilization when using lumbar orthoses after spinal fusion in patients adequately cooperating to minimize gross body motions. PMID:8316887

  10. [Johann Wilhelm Ritter (1776-1810) and the discovery of ultraviolet irradiation 185 years ago].

    PubMed

    Barth, J

    1987-05-01

    On 22 February 1801, Johann Wilhelm Ritter discovered UV radiation in Jena. In general, this achievement is less well known than his work on galvanism. Ritter was the creator of modern electrochemistry. Though since described as "the most brilliant physicist of the Romantic period," he was a controversial figure in his own time. His scientific work was not fully acknowledged until after his death. PMID:3301744

  11. Effect of lumbar orthosis on intervertebral mobility. A roentgen stereophotogrammetric analysis.

    PubMed

    Axelsson, P; Johnsson, R; Strömqvist, B

    1992-06-01

    To determine the stabilizing effect of external lumbar supports on the intervertebral mobility in the lower lumbar spine, seven patients with a posterolateral lumbosacral fusion without internal fixation were examined by roentgen stereophotogrammetric analysis in supine and erect positions 1 month after surgery, that is, after soft tissue healing but before fusion consolidation. Each patient was examined without lumbar support, with a molded, rigid orthosis and with a canvas corset with molded, plastic posterior support. Neither of the two types of lumbar support had any stabilizing effect on the sagittal, vertical, or transverse intervertebral translations. This study using roentgen stereophotogrammetric analysis confirms that lumbosacral orthosis has effect by restricting gross motions of the trunk rather than intervertebral mobility in the lumbar spine. PMID:1626301

  12. High Resolution Imager (HRI) for the Roentgen Satellite (ROSAT) definition study

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The design of the high resolution imager (HRI) on HEAO 2 was modified for use in the instrument complement of the Roentgen Satellite (ROSAT). Mechanical models of the front end assembly, central electronics assembly, and detector assembly were used to accurately represent the HRI envelope for both fit checks and focal plane configuration studies. The mechanical and electrical interfaces were defined and the requirements for electrical ground support equipment were established. A summary description of the ROSAT telescope and mission is included.

  13. The use of Roentgen stereophotogrammetry to study micromotion of orthopaedic implants

    NASA Astrophysics Data System (ADS)

    Valstar, Edward R.; Nelissen, Rob G. H. H.; Reiber, Johan H. C.; Rozing, Piet M.

    Roentgen stereophotogrammetry is the most accurate Roentgen technique for three-dimensional assessment of micromotion of orthopaedic implants. The reported accuracy of Roentgen Stereophotogrammetric Analysis (RSA) ranges between 0.05 and 0.5 mm for translations and between 0.15° and 1.15° for rotations. Because of the high accuracy of RSA, small patient groups are in general sufficient to study the effect on prosthetic fixation due to changes in implant design, addition of coatings, or new bone cements. By assessing micromotion of a prosthesis in a short-term (i.e. 2 years) clinical RSA study, a prediction can be made on the chance of long-term (i.e. 10 years) loosening of the prosthesis. Therefore, RSA is an important measurement tool to screen new developments in prosthetic design, and to prevent large groups of patients from being exposed to potentially inferior designs. In this article, the basics of the RSA technique are explained, and the importance of clinical RSA studies is illustrated with two examples of clinical RSA studies which RSA delivered very valuable information. Thereafter, two recent developments in RSA that have been implemented at Leiden University Medical Center are presented: digital automated measurements in RSA radiographs and model-based RSA.

  14. Les Observatoires astronomiques en Italie. An 1863 Report by Otto Wilhelm Struve.

    PubMed

    Bianchi, Simone; Galli, Daniele

    2015-01-01

    In the autumn of 1863 Otto Wilhelm Struve, director of the Pulkovo Astronomical Observatory in Russia, visited most of the observatories in Italy. The report that he wrote on this occasion provides an overview on the conditions of astronomical research in Italyjust after the unification of the country. Later Struve sent a French translation of his report to the Italian astronomer Giovan Battista Donati, who used it to promote the construction of the Arcetri Observatory in Florence, which was inaugurated in 1872. We present here a transcription of the French translation of Struve's report and the transcription of a letter written by him in support of Donati's project PMID:26495588

  15. The Nazi symbiosis: politics and human genetics at the Kaiser Wilhelm Institute.

    PubMed

    Berez, Thomas M; Weiss, Sheila Faith

    2004-12-01

    The case of the Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics (KWIA), from its inception in Weimar Republic Germany to its apogee under the rule of the Third Reich, is an example of how politics and human heredity can function as mutually beneficial resources. Whether it was a result of the Nazi bureaucrats' desire to legitimize their racial policy through science, or the KWIA personnel's desire to secure more funding for their research, the symbiotic relationship that developed between human genetics and Nazi politics could help explain why many scientists in the Third Reich undertook research projects that wholly transgressed the boundaries of morally acceptable science. PMID:15571767

  16. "My goose child Martina": the multiple uses of geese in the writings of Konrad Lorenz.

    PubMed

    Munz, Tania

    2011-01-01

    In 1935, the graylag goose Martina (1935-?) hatched from an egg in the home of the zoologist Konrad Lorenz (1903-1989). Martina imprinted on Lorenz, slept in his bedroom, mated with the gander Martin, and flew off in 1937. Over the following decades, Konrad Lorenz helped to establish the discipline of ethology, received a share of the 1973 Nobel Prize in Physiology or Medicine, and continued to write about his famous goose Martina. This essay examines the different instantiations of the geese in general, and Martina in particular, in Lorenz's writings aimed at readerships that included prewar zoologists, National Socialist psychologists, and popular audiences from the 1930s to 1980s. By developing an animal with her own biography, Lorenz created an individual whose lived and rhetorical agency made her especially well suited to perform widely divergent aspects of his evolving science. While a significant literature in the history of science has explored the standardization and stabilization of animals in science, I show how Lorenz's creation of a highly protean and increasingly public Martina was co-constitutive of the establishment of the science and public persona. PMID:22363967

  17. Replication and Pedagogy in the History of Psychology V: The Metronome and Wilhelm Wundt's Search for the Components of Consciousness

    ERIC Educational Resources Information Center

    Ayala, Christopher; Borawski, Steven; Miller, Jonathon

    2008-01-01

    Wilhelm Wundt (1832-1920) believed that consciousness was represented by the interconnection of psychical processes comprised of temporal elements and compounds. To explore these processes, Wundt used a metronome to measure the amount of information that passed into consciousness across time. The current project replicated some of his procedures,…

  18. Improved execution efficiency of model-based roentgen stereophotogrammetric analysis: simplification and segmentation of model meshes.

    PubMed

    Syu, Ci-Bin; Lin, Shang-Chih; Huang, Chung-Yi; Lai, Jiing-Yih; Shih, Kao-Shang; Chen, Kuo-Jen

    2012-01-01

    Recently, the model-based roentgen stereophotogrammetric analysis (RSA) method has been developed as an in vivo tool to estimate static pose and dynamic motion of the instrumented prostheses. The two essential inputs for the RSA method are prosthetic models and roentgen images. During RSA calculation, the implants are often reversely scanned and input in the form of meshes to estimate the outline error between prosthetic projection and roentgen images. However, the execution efficiency of the RSA iterative calculation may limit its clinical practicability, and one reason for inefficiency may be very large number of meshes in the model. This study uses two methods of mesh manipulation to improve the execution efficiency of RSA calculation. The first is to simplify the model meshes and the other is to segment and delete the meshes of insignificant regions. An index (i.e. critical percentage) of an optimal element number is defined as the trade-off between execution efficiency and result accuracy. The predicted results are numerically validated by total knee prosthetic system. The outcome shows that the optimal strategy of the mesh manipulation is simplification and followed by segmentation. On average, the element number can even be reduced to 1% of the original models. After the mesh manipulation, the execution efficiency can be increased about 75% without compromising the accuracy of the predicted RSA results (the increment of rotation and translation error: 0.06° and 0.02 mm). In conclusion, prosthetic models should be manipulated by simplification and segmentation methods prior to the RSA calculation to increase the execution efficiency and then to improve clinical applicability of the RSA method. PMID:22401491

  19. [Thorotrast deposits in the RES of the liver and spleen--a rare but characteristic roentgen diagnosis].

    PubMed

    Kegel, W

    1984-08-01

    Finely reticulated or granulated shadows of liver and spleen, as well as metal-dense shadows of abdominal lymph nodes are characteristic roentgen findings in thorotrastosis. Thorium dioxide (Thorotrast) was used as a contrast medium from 1930-1950. It yielded excellent contrast and was well tolerated, but due to its radioactivity and its long biological half-life it caused manifold late complications. The typical roentgen findings in thorotrastosis are illustrated by two cases; the importance of thorotrastosis is discussed on the basis of relevant literature. PMID:6484464

  20. The holist tradition in twentieth century genetics. Wilhelm Johannsen's genotype concept

    PubMed Central

    Roll-Hansen, Nils

    2014-01-01

    The terms ‘genotype’, ‘phenotype’ and ‘gene’ originally had a different meaning from that in the Modern Synthesis. These terms were coined in the first decade of the twentieth century by the Danish plant physiologist Wilhelm Johannsen. His bean selection experiment and his theoretical analysis of the difference between genotype and phenotype were important inputs to the formation of genetics as a well-defined special discipline. This paper shows how Johannsen's holistic genotype theory provided a platform for criticism of narrowly genocentric versions of the chromosome theory of heredity that came to dominate genetics in the middle decades of the twentieth century. Johannsen came to recognize the epoch-making importance of the work done by the Drosophila group, but he continued to insist on the incompleteness of the chromosome theory. Genes of the kind that they mapped on the chromosomes could only give a partial explanation of biological heredity and evolution. PMID:24882823

  1. Wilhelm Conrad Röntgen (1845-1923) and the 1914 affair.

    PubMed

    Isherwood, Ian

    2004-05-01

    In August 1914 the university library of Leuven (Louvain) was destroyed by the German occupying forces. In October 1914 an Appeal was addressed to "The World of Culture" by 93 German academics and artists in which they disclaimed any German responsibility--"It is not true that our troops have brutally destroyed Louvain". The Appeal had a profound, although mainly negative, effect, especially in the United States, where it almost certainly influenced that country's decision to enter the conflict. Signatories to the Appeal included Wilhelm Conrad Röntgen, the discoverer of X-rays. Why did Röntgen sign such an extraordinary and untrue statement? He claimed that he had not read it, but both the personal and political backgrounds to his action were complex and are worthy of further scrutiny. This paper explores the issue and the reception of the notorious Appeal by the British radiology community. PMID:15079167

  2. The first ascent to the volcano Cotopaxi in Ecuador by Wilhelm Reiss (1838-1908)

    NASA Astrophysics Data System (ADS)

    Pfaffl, Fritz A.; Dullo, Wolf-Christian

    2014-06-01

    The volcano Cotopaxi in South America is 5,897 m high and is one of the highest active volcanoes of the world and the second highest volcano in the Andes after the Chimborazo (6,310 m). In Ecuador, there are more than 20 volcanoes contributing to the spectacular mountain range diving this country between the western and eastern lowlands. There have been more than 50 reports of volcanic activity at Cotopaxi since 1738, among which those from the years 1744, 1768, and 1877 are the largest. During the 1877 eruption, the whole summit glacier collapsed and a huge mudflow spread out for more than 100 km and flooded the city of Latacunga. Five years prior to this catastrophic event, the German geologist Wilhelm Reiss from the University of Heidelberg ascended Cotopaxi for the first time together with his supporter Angel M. Escobar from Columbia.

  3. The holist tradition in twentieth century genetics. Wilhelm Johannsen's genotype concept.

    PubMed

    Roll-Hansen, Nils

    2014-06-01

    The terms 'genotype', 'phenotype' and 'gene' originally had a different meaning from that in the Modern Synthesis. These terms were coined in the first decade of the twentieth century by the Danish plant physiologist Wilhelm Johannsen. His bean selection experiment and his theoretical analysis of the difference between genotype and phenotype were important inputs to the formation of genetics as a well-defined special discipline. This paper shows how Johannsen's holistic genotype theory provided a platform for criticism of narrowly genocentric versions of the chromosome theory of heredity that came to dominate genetics in the middle decades of the twentieth century. Johannsen came to recognize the epoch-making importance of the work done by the Drosophila group, but he continued to insist on the incompleteness of the chromosome theory. Genes of the kind that they mapped on the chromosomes could only give a partial explanation of biological heredity and evolution. PMID:24882823

  4. Automatic model-based roentgen stereophotogrammetric analysis (RSA) of total knee prostheses.

    PubMed

    Syu, Ci-Bin; Lai, Jiing-Yih; Chang, Ren-Yi; Shih, Kao-Shang; Chen, Kuo-Jen; Lin, Shang-Chih

    2012-01-01

    Conventional radiography is insensitive for early and accurate estimation of the mal-alignment and wear of knee prostheses. The two-staged (rough and fine) registration of the model-based RSA technique has recently been developed to in vivo estimate the prosthetic pose (i.e, location and orientation). In the literature, rough registration often uses template match or manual adjustment of the roentgen images. Additionally, possible error induced by the nonorthogonality of taking two roentgen images neither examined nor calibrated prior to fine registration. This study developed two RSA methods for automate the estimation of the prosthetic pose and decrease the nonorthogonality-induced error. The predicted results were validated by both simulative and experimental tests and compared with reported findings in the literature. The outcome revealed that the feature-recognized method automates pose estimation and significantly increases the execution efficiency up to about 50 times in comparison with the literature counterparts. Although the nonorthogonal images resulted in undesirable errors, the outline-optimized method can effectively compensate for the induced errors prior to fine registration. The superiority in automation, efficiency, and accuracy demonstrated the clinical practicability of the two proposed methods especially for the numerous fluoroscopic images of dynamic motion. PMID:22093794

  5. Refracting Roentgen's rays: Propagation-based x-ray phase contrast for biomedical imaging

    SciTech Connect

    Gureyev, T. E.; Mayo, S. C.; Nesterets, Ya.; Pogany, A.; Stevenson, A. W.; Wilkins, S. W.; Myers, D. E.; Paganin, D. M.

    2009-05-15

    Absorption-contrast x-ray imaging serves to visualize the variation in x-ray attenuation within the volume of a given sample, whereas phase contrast allows one to visualize variations in x-ray refractive index. The former imaging mechanism has been well known and widely utilized since the time of Roentgen's Nobel prize winning work, whereas the latter mechanism--sought for, but not found, by Roentgen himself--has laid the foundation for a revolution in x-ray imaging which is the central topic of this review. We consider the physical imaging mechanisms underlying both absorption contrast and phase contrast, together with the associated inverse problem of how one may obtain quantitative two- or three-dimensional information regarding a sample, given one or more phase-contrast images of the same. Practical questions are considered, regarding optimized phase-contrast imaging geometries as a function of detector resolution, source size, x-ray spectrum, and dose. Experimental examples pertaining to biomedical applications are given, and prospects for the future outlined.

  6. PREFACE: The 395th Wilhelm and Else Heraeus Seminar: `Time-dependent phenomena in Quantum Mechanics'

    NASA Astrophysics Data System (ADS)

    Kleber, Manfred; Kramer, Tobias

    2008-03-01

    The 395th Wilhelm and Else Heraeus Seminar: `Time-dependent phenomena in Quantum Mechanics' took place at the Heinrich Fabri Institute in Blaubeuren, Germany, 12-16 September 2007. The conference covered a wide range of topics connected with time-dependent phenomena in quantum mechanical systems. The 20 invited talks and 15 short talks with posters at the workshop covered the historical debate between Schrödinger, Dirac and Pauli about the role of time in Quantum Mechanics (the debate was carried out sometimes in footnotes) up to the almost direct observation of electron dynamics on the attosecond time-scale. Semiclassical methods, time-delay, monodromy, variational principles and quasi-resonances are just some of the themes which are discussed in more detail in the papers. Time-dependent methods also shed new light on energy-dependent systems, where the detour of studying the time-evolution of a quantum states allows one to solve previously intractable problems. Additional information is available at the conference webpage http://www.quantumdynamics.de The organizer would like to thank all speakers, contributors, session chairs and referees for their efforts in making the conference a success. We also gratefully acknowledge the generous financial support from the Wilhelm and Else Heraeus Foundation for the conference and the production of this special volume of Journal of Physics: Conference Series. Manfred Kleber Physik Department T30, Technische Universität München, 85747 Garching, Germany mkleber@ph.tum.de Tobias Kramer Institut I: Theoretische Physik, Universität Regensburg, 93040 Regensburg, Germany tobias.kramer@physik.uni-regensburg.de Guest Editors Conference photograph Front row (from left): W Schleich, E J Heller, J B Delos, H Friedrich, K Richter, M Kleber, P Kramer, M Man'ko, A del Campo, V Man'ko, M Efremov, A Ruiz, M O Scully Middle row: A Zamora, R Aganoglu, T Kramer, J Eiglsperger, H Cruz, P Raab, I Cirac, G Muga, J Larson, V Dodonov, W Becker Back row: A Eckardt, A Siddiki, K Vafayi, M Holthaus, E Räsänen, M Rodriguez, O Kullie, D Milošević, J Briggs, A Ribeiro, (not in the picture W Zwerger)

  7. Fluoroscopic Roentgen stereophotogrammetric analysis (FRSA) to study three-dimensional stent graft dynamics.

    PubMed

    Koning, Olivier H J; Kaptein, Bart L; van der Vijver, Rozemarijn; Dias, Nuno V; Malina, Martin; Schalij, Martin J; Valstar, Edward R; van Bockel, J Hajo

    2009-08-01

    We report the clinical feasibility of fluoroscopic Roentgen stereophotogrammetric analysis (FRSA), a validated method to quantify real time three-dimensional (3D) dynamic motion of stent grafts and the first clinical results after abdominal and thoracic endovascular repair (EVAR). Stent graft motion was measured at 30 (stereo) frames per second, during the cardiac cycle and in the patient after abdominal EVAR, due to respiratory action. Translational motions of the center of mass, diameter change, and rotational and axial motion could be measured. Quantification of 3D motion was not available until now. FRSA can provide crucial information on the forces exerted on stent grafts and will, therefore, provide essential information for improvements in stent graft design. PMID:19631876

  8. Bladder tumors and aromatic amines - historical milestones from Ludwig Rehn to Wilhelm Hueper.

    PubMed

    Dietrich, Holger Georg; Golka, Klaus

    2012-01-01

    We know today that environmental factors must be regarded as a significant cause of the urinary bladder carcinoma. In Germany, the urinary bladder carcinoma is the second most common urological tumor among men and the most common among women and more than 100 occupational bladder cases are recognized and compensated per year. Scientific studies of this problem reach back to the 18th century. However it was only in 1895 that the surgeon Ludwig Rehn firstly described 3 cases of occupational bladder tumors in at most 45 fuchsine workers in Frankfurt / M. This extremely significant discovery was followed by a description of a large number of cases of urinary bladder tumors among workers in the paint industry. Nevertheless, it was impossible to induce bladder cancer in animals by aromatic amines for many years. In the 1930s, the pathologist Wilhelm C. Hueper was the first to induce bladder cancer in animal experiments, applying beta-naphthylamine to dogs. Based on these experiments and corroborated by epidemiologic studies, beta-naphthylamine was banned in Germany and many countries from the 1950s on. This review will highlight work and life of these two pioneering medical researchers. PMID:22201870

  9. From Wilhelm von Humboldt to Hitler-are prominent people more prone to have Parkinson's disease?

    PubMed

    Horowski; Horowski; Calne; Calne

    2000-10-01

    We describe Parkinsonism in prominent people, where Wilhelm von Humboldt and Adolf Hitler provide just two spectacular, opposing examples. In both of them, there is little if any evidence that the disease did influence their life ambitions, methods of achieving them or cognitive function in general. Thus, Hitler's Parkinsonism should remain a 'footnote' to history, and historians should acknowledge that in his last years, his trembling, his curbed posture, his slow walking, mask-like face and low voice did not indicate remorse, fear or depression as a consequence of his crimes, but were mere expressions of his disease which, until the end, had no impact on his intellectual skills and methods. The apparently higher incidence of Parkinsonism in prominent people may be just due to their higher visibility, or a consequence of disease-related personality traits (e.g. ambition, perfectionism, rigidity) which may contribute to becoming, e.g., a prominent authoritarian person. Perhaps even some early behaviour pattern (such as repressed emotions or acting in public-which could even increase the risk of some infection) contributes to a greater vulnerability for developing Parkinsonism. Further studying other prominent cases might lead us to better understanding of risk factors and the expression of early Parkinsonism. PMID:10900395

  10. Covariation of sea ice and methanesulphonic acid in Wilhelm II Land, East Antarctica

    NASA Astrophysics Data System (ADS)

    Foster, Annette F. M.; Curran, Mark A. J.; Smith, Barbara T.; van Ommen, Tas D.; Morgan, Vin I.

    Sea ice plays an important role in ocean-atmosphere heat exchange, global albedo and the marine ecosystem. Knowledge of variation in sea-ice extent is essential in order to understand past climates, and to model possible future climate scenarios. This paper presents results from a short firn core spanning 15 years collected from near Mount Brown, Wilhelm II Land, East Antarctica. Variations of methanesulphonic acid (MSA) at Mount Brown were positively correlated with sea-ice extent from the coastal region surrounding Mount Brown (60-120° E) and from around the entire Antarctic coast (0-360° E). Previous results from Law Dome identified this MSA-sea-ice relationship and proposed it as an Antarctic sea-ice proxy (Curran and others, 2003), with the strongest results found for the local Law Dome region. Our data provide supporting evidence for the Law Dome proxy (at another site in East Antarctica), but a deeper Mount Brown ice core is required to confirm the sea-ice decline suggested by Curran and others (2003). Results also indicate that this deeper record may also provide a more circum-Antarctic sea-ice proxy.

  11. Discovering environmental cancer: Wilhelm Hueper, post-World War II epidemiology, and the vanishing clinician's eye.

    PubMed Central

    Sellers, C

    1997-01-01

    Today, our understanding of and approach to the exogenous causes of cancer are dominated by epidemiological practices that came into widespread use after World War II. This paper examines the forces, considerations, and controversies that shaped postwar risk factor epidemiology in the United States. It is argued that, for all of the new capabilities it brought, this risk factor epidemiology has left us with less of a clinical eye for unrecognized cancer hazards, especially from limited and localized exposures in the work-place. The focus here is on Wilhelm Hueper, author of the first textbook on occupational cancer (1942). Hueper became the foremost spokesman for earlier identification practices centering on occupational exposures. The new epidemiological methods and associated institutions that arose in the 1940s and 1950s bore an unsettled relation to earlier claims and methods that some, Hueper among them, interpreted as a challenge. Hueper's critique of the new epidemiology identified some of its limitations and potentially debilitating consequences that remain with us today. Images p1825-a p1827-a p1829-a PMID:9366640

  12. Johann Wilhelm Hittorf and the material culture of nineteenth-century gas discharge research.

    PubMed

    Müller, Falk

    2011-06-01

    In the second half of the nineteenth century, gas discharge research was transformed from a playful and fragmented field into a new branch of physical science and technology. From the 1850s onwards, several technical innovations-powerful high-voltage supplies, the enhancement of glass-blowing skills, or the introduction of mercury air-pumps- allowed for a major extension of experimental practices and expansion of the phenomenological field. Gas discharge tubes served as containers in which resources from various disciplinary contexts could be brought together; along with the experimental apparatus built around them the tubes developed into increasingly complex interfaces mediating between the human senses and the micro-world. The focus of the following paper will be on the physicist and chemist Johann Wilhelm Hittorf (1824-1914), his educational background and his attempts to understand gaseous conduction as a process of interaction between electrical energy and matter. Hittorf started a long-term project in gas discharge research in the early 1860s. In his research he tried to combine a morphological exploration of gas discharge phenomena-aiming at the experimental production of a coherent phenomenological manifold--with the definition and precise measurements of physical properties. PMID:21879606

  13. Selection within organisms in the nineteenth century: Wilhelm Roux's complex legacy.

    PubMed

    Heams, Thomas

    2012-09-01

    Selectionism, or the extension of darwinian chance/selection dynamics beyond the individual level, has a long history in biological thought. It has generated important theories in immunology or neurology, and turns out to be a convincing framework to account for the intrinsic stochastic nature of core events in cellular biology. When looking back at the intellectual origins of selectionism, the essay by the German embryologist Wilhelm Roux, Der Kampf der Theile im Organismus (The Struggle of the Parts in the Organism - 1881) might be one, if not the earliest reference after the darwinian revolution. It describes the individual as a multilevel structure, where each level results from a 'darwinian' struggle of its parts (molecules, cells, tissues, organs). But Roux's theory, far from being a simple extension of natural selection, has complex and even conflictual relationships with darwinism. This essay is worth rediscovering as a subtle historical testimony of the evolutionary and developmental life sciences debates of its time. Moreover, some of its theses may also enrich some current debates among evolutionary biologists over levels of selection, and among cellular and molecular biologists over the status of determinism in biology today. PMID:22525790

  14. Carl Wilhelm Scheele, the discoverer of oxygen, and a very productive chemist.

    PubMed

    West, John B

    2014-12-01

    Carl Wilhelm Scheele (1742-1786) has an important place in the history of the discovery of respiratory gases because he was undoubtedly the first person to prepare oxygen and describe some of its properties. Despite this, his contributions have often been overshadowed by those of Joseph Priestley and Antoine Lavoisier, who also played critical roles in preparing the gas and understanding its nature. Sadly, Scheele was slow to publish his discovery and therefore Priestley is rightly recognized as the first person to report the preparation of oxygen. This being said, the thinking of both Scheele and Priestley was dominated by the phlogiston theory, and it was left to Lavoisier to elucidate the true nature of oxygen. In addition to his work on oxygen, Scheele was enormously productive in other areas of chemistry. Arguably he discovered seven new elements and many other compounds. However, he kept a low profile during his life as a pharmacist, and he did not have strong links with contemporary prestigious institutions such as the Royal Society in England or the French Académie des Sciences. He was elected to the Royal Swedish Academy of Science but only attended one meeting. Partly as a result, he remains a somewhat nebulous figure despite the critical contribution he made to the history of respiratory gases and his extensive researches in other areas of chemistry. His death at the age of 43 may have been hastened by his habit of tasting the chemicals that he worked on. PMID:25281638

  15. Physiological optics, cognition and emotion: a novel look at the early work of Wilhelm Wundt.

    PubMed

    Wassmann, Claudia

    2009-04-01

    The German physiologist Wilhelm Wundt, who later founded experimental psychology, arguably developed the first modern scientific conception of emotion. In the first edition of Vorlesungen über die Menschen- und Thierseele (Lectures on human and animal psychology), which was published in 1863, Wundt tried to establish that emotions were essential parts of rational thought. In fact, he considered them unconscious steps of decision-making that were implied in all processes of conscious thought. His early work deserves attention not only because it is the attempt to conceptualize cognition and emotion strictly from a neural point of view but also because it represents the very foundation of the debate about the nature of emotion that revolved around William James' theory of emotion during the 1890s. However, this aspect of his work is little known because scholars who have analyzed Wundt's work focused on his late career. Furthermore, historical analysis interpreted Wundt's work within a philosophical framework, rather than placing it in the context of German medical and physiological research in which it belongs. In addition, Wundt's early works are hardly available to an English speaking audience because they were never translated. PMID:18948411

  16. The relative skin movement of the foot: a 2-D roentgen photogrammetry study.

    PubMed

    Tranberg, Roy; Karlsson, Dan

    1998-01-01

    OBJECTIVE: This paper describes a validation of the relative motions of skin-mounted markers on the foot. DESIGN: The movement of a skin-mounted marker on the foot was evaluated by the use of 2-D roentgen photogrammetry. BACKGROUND: Validations of skin-mounted markers are needed in order to assess whether clinical use of motion analysis systems is accurate. METHODS: Six healthy volunteers participated in the study. Measurements were made with 2-D roentgen photogrammetry from the medial aspect of the foot. Spherical lead markers, with a diameter of 2 mm, were glued on the skin over the following landmarks: the medial malleolus, the navicular bone, the medial part of calcaneus, the base and the head of the first metatarsal bone, and the base of the fifth metatarsal bone. The foot was placed on a platform that was adjustable in three directions: horizontal, 20 degrees upward (towards dorsal flexion), and 30 degrees downward (towards plantar flexion). RESULTS: In relation to the underlying bones, the markers were found to move up to 4.3 mm. The markers with the largest movements were the ones over the medial malleolus, the navicular bone and the calcaneus. For the distally placed markers i.e. at the base and the head of the first metatarsal bone, and the base of the fifth metatarsal bone, the displacements were a maximum 1.8 mm. CONCLUSIONS: Markers mounted on the foot moved between 1.8 and 4.3 mm corresponding to the underlying bones. The most proximal attached markers demonstrated the largest movements. PMID:11415773

  17. A new type of model-based Roentgen stereophotogrammetric analysis for solving the occluded marker problem.

    PubMed

    Kaptein, B L; Valstar, E R; Stoel, B C; Rozing, P M; Reiber, J H C

    2005-11-01

    Roentgen stereophotogrammetric analysis (RSA) measures micromotion of an orthopaedic implant with respect to its surrounding bone. A problem in RSA is that the markers are sometimes overprojected by the implant itself. This study describes the so-called Marker Configuration Model-based RSA (MCM-based RSA) that is able to measure the pose of a rigid body in situations where less than three markers could be detected in both images of an RSA radiograph. MCM-based RSA is based on fitting a Marker Configuration model (MC-model) to the projection lines from the marker projection positions in the image to their corresponding Roentgen foci. An MC-model describes the positions of markers relative to each other and is obtained using conventional RSA. We used data from 15 double examinations of a clinical study of total knee prostheses and removed projections of the three tibial component markers, simulating occlusion of markers. The migration of the tibial component with respect to the bone, which should be zero, for the double examination is a measure of the accuracy of algorithm. With the new algorithm, it is possible to estimate the pose of a rigid body of which one or two markers are occluded in one of the images of the RSA radiograph with high accuracy as long as a proper MC-model of the markers in the rigid body is available. The new algorithm makes RSA more robust for occlusion of markers. This improves the results of clinical RSA studies because the number of lost RSA follow-up moments is reduced. PMID:16154422

  18. A biplane roentgen videometry system for dynamic /60 per second/ studies of the shape and size of circulatory structures, particularly the left ventricle.

    NASA Technical Reports Server (NTRS)

    Ritman, E. L.; Sturm, E.; Wood, E. H.; Heintzen, P. H.

    1971-01-01

    A roentgen-television digital-computer technique and a display system developed for dynamic circulatory structure studies are described. Details are given for a videoroentgenographic setup which is used for obtaining biplane roentgen silhouettes of a left ventricle. A 60 per sec measurement of the shape and volume of angiographically outlined cardiac chambers can be made by this technique along with simultaneous ECG, pressure, and flow measurements accessible for real-time digital computer processing and analysis.

  19. Replication and Pedagogy in the History of Psychology V: The Metronome and Wilhelm Wundt's Search for the Components of Consciousness

    NASA Astrophysics Data System (ADS)

    Ayala, Christopher; Borawski, Steven; Miller, Jonathon

    2008-05-01

    Wilhelm Wundt (1832 1920) believed that consciousness was represented by the interconnection of psychical processes comprised of temporal elements and compounds. To explore these processes, Wundt used a metronome to measure the amount of information that passed into consciousness across time. The current project replicated some of his procedures, to better understand the role of introspection and the complexity of the metronome task for experimenters and observers. The results of the replication were mixed, but the replication helped provide insights into Wundt’s procedures and their relationship to his theories.

  20. [Radiation protection. Implications for clinical practice on the new regulations governing roentgen ray irradiation and radioprotection].

    PubMed

    Nestle, U; Berlich, J

    2006-08-01

    In 2001 or 2002, the legislator made substantial alterations to the "Röntgenverordnung" [regulations governing use of roentgen ray radiation] and "Strahlenschutzverordnung" [regulations governing radiation protection]. This was done to bring German law in line with EU Directives 96/29/Euratom (basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation) and 97/43/Euratom (health protection of individuals against the dangers of ionizing radiation in relation to medical exposure). Proper use of radiation in medicine requires that those involved in its application are aware of the biological effect of radiation. When staff and others are protected good organization and appropriate technology at the workplace can achieve a great deal. In the new directives, the radiation protection for the patient is quantified and the responsibility of the physician is clearly pointed out. The most important aim is uniform quality throughout Europe in radiological diagnosis and radiation protection. PMID:17180754

  1. Image-based RSA: Roentgen stereophotogrammetric analysis based on 2D-3D image registration.

    PubMed

    de Bruin, P W; Kaptein, B L; Stoel, B C; Reiber, J H C; Rozing, P M; Valstar, E R

    2008-01-01

    Image-based Roentgen stereophotogrammetric analysis (IBRSA) integrates 2D-3D image registration and conventional RSA. Instead of radiopaque RSA bone markers, IBRSA uses 3D CT data, from which digitally reconstructed radiographs (DRRs) are generated. Using 2D-3D image registration, the 3D pose of the CT is iteratively adjusted such that the generated DRRs resemble the 2D RSA images as closely as possible, according to an image matching metric. Effectively, by registering all 2D follow-up moments to the same 3D CT, the CT volume functions as common ground. In two experiments, using RSA and using a micromanipulator as gold standard, IBRSA has been validated on cadaveric and sawbone scapula radiographs, and good matching results have been achieved. The accuracy was: |mu |< 0.083 mm for translations and |mu| < 0.023 degrees for rotations. The precision sigma in x-, y-, and z-direction was 0.090, 0.077, and 0.220 mm for translations and 0.155 degrees , 0.243 degrees , and 0.074 degrees for rotations. Our results show that the accuracy and precision of in vitro IBRSA, performed under ideal laboratory conditions, are lower than in vitro standard RSA but higher than in vivo standard RSA. Because IBRSA does not require radiopaque markers, it adds functionality to the RSA method by opening new directions and possibilities for research, such as dynamic analyses using fluoroscopy on subjects without markers and computer navigation applications. PMID:17706656

  2. Development of Mirror Modules for the ART-XC Instrument aboard the Spectrum-Roentgen-Gamma Mission

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail V.; Ramsey, Brian; O'Dell, Stephen L.; Elsner, Ronald F.; Kilaru, Kiranmayee; Atkins, Carolyn; Pavlinskiy, Mikhail N.; Tkachenko, Alexey V.; Lapshov, Igor Y.

    2013-01-01

    The Marshall Space Flight Center (MSFC) is developing x-ray mirror modules for the Astronomical Roengen Telescope- X-ray Concentrator (ART-XC) instrument on board the Spectrum-Roentgen-Gamma Mission. ART-XC will consist of seven co-aligned x-ray mirror modules with seven corresponding CdTe focal plane detectors. Each module provides an effective area of 65 sq cm at 8 keV, response out to 30 keV, and an angular resolution of 45 arcsec or better HPD. We will present a status of the ART x-ray module development at MSFC.

  3. Wilhelm Reich's self-censorship after his arrest as an enemy alien: the chilling effect of an illegal imprisonment.

    PubMed

    Bennett, Philip W

    2014-04-01

    After discussing Wilhelm Reich's place in psychoanalysis, the article explores his arrest as an 'enemy alien' in December 1941. Reich's emotional responses to his imprisonment (which was illegal and which lasted nearly a month) are explored. A number of scholars have suggested that many European radical psychoanalysts refrained from sharing their former political ideas once they emigrated to the United States. Following a brief discussion of this pattern of 'silencing,' it is argued that Reich's withholding certain documents from publication was due to a self-imposed censorship, motivated in part by the fear of further governmental interference with his life and work. This fear, however, did not extend to his discussion of his newly developed theory of orgone energy. PMID:24628260

  4. Experimental analysis of Model-Based Roentgen Stereophotogrammetric Analysis (MBRSA) on four typical prosthesis components.

    PubMed

    Seehaus, Frank; Emmerich, Judith; Kaptein, Bart L; Windhagen, Henning; Hurschler, Christof

    2009-04-01

    Classical marker-based roentgen stereophotogrammetric analysis (RSA) is an accurate method of measuring in vivo implant migration. A disadvantage of the method is the necessity of placing tantalum markers on the implant, which constitutes additional manufacturing and certification effort. Model-based RSA (MBRSA) is a method by which pose-estimation of geometric surface-models of the implant is used to detect implant migration. The placement of prosthesis markers is thus no longer necessary. The accuracy of the pose-estimation algorithms used depends on the geometry of the prosthesis as well as the accuracy of the surface models used. The goal of this study was thus to evaluate the experimental accuracy and precision of the MBRSA method for four different, but typical prosthesis geometries, that are commonly implanted. Is there a relationship existing between the accuracy of MBRSA and prosthesis geometries? Four different prosthesis geometries were investigated: one femoral and one tibial total knee arthroplasty (TKA) component and two different femoral stem total hip arthroplasty (THA) components. An experimental phantom model was used to simulate two different implant migration protocols, whereby the implant was moved relative to the surrounding bone (relative prosthesis-bone motion (RM)), or, similar to the double-repeated measures performed to assess accuracy clinically, both the prosthesis and the surrounding bone model (zero relative prosthesis-bone motion (ZRM)) were moved. Motions were performed about three translational and three rotational axes, respectively. The maximum 95% confidence interval (CI) for MBRSA of all four prosthesis investigated was better than -0.034 to 0.107 mm for in-plane and -0.217 to 0.069 mm for out-of-plane translation, and from -0.038 deg to 0.162 deg for in-plane and from -1.316 deg to 0.071 deg for out-of-plane rotation, with no clear differences between the ZRM and RM protocols observed. Accuracy in translation was similar between TKA and THA components, whereas rotational accuracy about the long axis of the hip stem THA components was worse than the TKA components. The data suggest that accuracy and precision of MBRSA seem to be equivalent to the classical marker-based RSA method, at least for the nonsymmetric implant geometries investigated in this study. The model-based method thus allows the accurate measurement of implant migration without requiring prosthesis markers, and thus presents new opportunities for measuring implant migration where financial or geometric considerations of marker placement have thus far been prohibitive factors. PMID:19275433

  5. [Capabilities of roentgen-endovascular surgery in conditions of the central multi-field clinical hospital union].

    PubMed

    Beliakin, S A; Ivanov, V A; Shklovskiĭ, B L; Ivanov, A V

    2013-05-01

    Spanning 45 years team of the Vishnevsky Central Military Clinical Hospital N 3 has achieved high results and made the Vishnevsky Central Military Clinical Hospital N 3 one of the best medical centers of Russia providing state-of-the art care for patients with cardiovascular diseases. Nowadays the Center of interventional radiology and treatment provides all methods of roentgen-endovascular interventions on coronary, peripheral, cerebral vasculature, veins and bile ducts. The center has modern diagnostic and treatment equipment: digital angiography system with 3-dimensional angiography, 3D-navigation and CT angiography. Annually, about 1500 diagnostic coronarography and about 500 percutaneous coronary interventions are performed in the hospital. More than a half of peripheral arterial intervention is endovascular. The examples of such operations as single-step iliac artery stenting, inferior vena cava thrombectomy, embolization of a dural arteriovenous fistula of the posterior cranial fossa, percutaneous transhepatic paracentetic cholangiostomy are given. PMID:24000616

  6. Comparison of the model-based and marker-based roentgen stereophotogrammetry methods in a typical clinical setting.

    PubMed

    Hurschler, Christof; Seehaus, Frank; Emmerich, Judith; Kaptein, Bart L; Windhagen, Henning

    2009-06-01

    Roentgen stereophotogrammetric analysis (RSA) is an established method for the precise measurement of implant migration. Model-based RSA (MBRSA) alleviates the need to attach tantalum markers to the prosthesis, which has prevented wider application of RSA. The goal of this study was to investigate the equivalence of both methods for the clinical measurement of implant migration. Tibial component migration was measured in 24 patients using both methods from the same set of radiographs. The maximum agreement interval, mean (+/-2 standard deviations), of the difference between both methods was modest, at 0.002 mm (0.144 mm) and -0.078 degrees (0.782 degrees ). The results suggest that MBRSA can be used interchangeably with the marker-based method and that the advantages of MBRSA do not come at the cost of a loss in accuracy. PMID:18676114

  7. Histrionicotoxins: roentgen-ray analysis of the novel allenic and acetylenie spiroalkaloids isolated from a Colombian frog, Dendrobates histrionicus.

    PubMed

    Daly, J W; Karle, I; Myers, C W; Tokuyama, T; Waters, J A; Witkop, B

    1971-08-01

    The structures and absolute configuration of two unique alkaloids isolated from the Colombian frog, Dendrobates histrionicus, have been elucidated by Roentgen-ray (x-ray) crystallography. Histrionicotoxin is (2pR, 6S, 7pS, 8aS)-7-(cis-1-buten-3-ynyl)-8-hydroxy-2-(cis-2-penten-4- ynyl)-1-azaspiro[5.5] undecane, while in dihydro-isohistrionicotoxin the acetylenic 2-pentenynyl side chain is replaced by an allenic 2-(3,4 pentadienyl) substituent. Dendrobates histrionicus exhibits remarkable interpopulational variations in amounts and composition of skin toxins, in behavior, and in phenotypic characters, aspects of which are illustrated in a color plate. The histrionico-toxins are the third class of alkaloids isolated from the defensive skin secretions of Neotropical (Dendrobatidae) frogs. PMID:5288773

  8. Histrionicotoxins: Roentgen-Ray Analysis of the Novel Allenic and Acetylenic Spiroalkaloids Isolated from a Colombian Frog, Dendrobates histrionicus

    PubMed Central

    Daly, John W.; Karle, Isabella; Myers, Charles W.; Tokuyama, Takashi; Waters, James A.; Witkop, Bernhard

    1971-01-01

    The structures and absolute configuration of two unique alkaloids isolated from the Colombian frog, Dendrobates histrionicus, have been elucidated by Roentgen-ray (x-ray) crystallography. Histrionicotoxin is (2pR, 6S, 7pS, 8aS)-7-(cis-1-buten-3-ynyl)-8-hydroxy-2-(cis-2-penten-4- ynyl)-1-azaspiro[5.5] undecane, while in dihydro-isohistrionicotoxin the acetylenic 2-pentenynyl side chain is replaced by an allenic 2-(3,4 pentadienyl) substituent. Dendrobates histrionicus exhibits remarkable interpopulational variations in amounts and composition of skin toxins, in behavior, and in phenotypic characters, aspects of which are illustrated in a color plate. The histrionico-toxins are the third class of alkaloids isolated from the defensive skin secretions of Neotropical (Dendrobatidae) frogs. Images PMID:5288773

  9. The many lives of experiments: Wilhelm Johannsen, selection, hybridization, and the complex relations of genes and characters.

    PubMed

    Meunier, Robert

    2016-04-01

    In addition to his experiments on selection in pure lines, Wilhelm Johannsen (1857-1927) performed less well-known hybridisation experiments with beans. This article describes these experiments and discusses Johannsen's motivations and interpretations, in the context of developments in early genetics. I will show that Johannsen first presented the hybridisation experiments as an additional control for his selection experiments. The latter were dedicated to investigating heredity with respect to debates concerning the significance of natural selection of continuous variation for evolution. In the course of the establishment of a Mendelian research program after 1900, the study of heredity gained increasing independence from questions of evolution, and focused more on the modes and mechanisms of heredity. Further to their role as control experiments, Johannsen also saw his hybridisation experiments as contributing to the Mendelian program, by extending the scope of the principles of Mendelian inheritance to quantitative characters. Towards the end of the first decade of genetics, Johannsen revisited his experiments to illustrate the many-many relationship between genes and characters, at a time when that relationship appeared increasingly complex, and the unit-character concept, accordingly, became inadequate. For the philosophy of science, the example shows that experiments can have multiple roles in a research programme, and can be interpreted in the light of questions other than those that motivated the experiments in the first place. PMID:26699626

  10. Treating Epiphora in Adults With the Wilhelm Plastic Nasolacrimal Stent: Mid-Term Results of a Prospective Study

    SciTech Connect

    Ciampi, Juan J. Lanciego, Carlos; Navarro, Sofia; Cuena, Rafael; Velasco, Javier; Perea, Miguel; Garcia-Garcia, Lorenzo

    2011-02-15

    The objective of the present study was to evaluate, in a prospective, single-center study, the effectiveness of the Wilhelm-type stent used in interventional radiology for the management of epiphora. Patients (n = 104; mean age 64 [range 25-88]; 33 male and 71 female) with severe epiphora had the stents inserted (135 stents in 115 eyes) to treat obstruction of the nasolacrimal system. The etiology of the obstruction was idiopathic in 83 cases, chronic dacryocystitis in 31, cases and postsurgical status in 1 case. The overall technical success rate of stent placement was near 94%. Resolution of epiphora was complete in 105 cases and partial in 3 cases. During a mean 13-month follow-up (range 1 week to 28 months), the median duration of primary patency was 11 months, and the percentage of patency at 6 months was 60.8%, at 1 year was 39.6%, and at 2 years was 25%. Stents malfunctioned in 54 cases, and all were easily withdrawn except in 1 case. Of these 27 cases, patency recovered spontaneously in 9 and by way of a second stent in 18. Secondary patency was 50%. Factors presdisposing to lower primary patency are inflammatory etiology and location of the obstruction. The benefit of stent deployment is clear with respect to the resolution of epiphora in candidate patients for percutaneous treatment. Technical and/or design improvements would be welcomed.

  11. The Marshall Space Flight Center Development of Mirror Modules for the ART-XC Ins1rument Aboard the Spectrum-Roentgen-Gamma Mission

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; ODell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2012-01-01

    The Spectrum-Rontgen-Gamma (SRG) mission is a Russian-German X-ray astrophysical observatory that carries two co-aligned and complementary X-ray telescope systems. The primary instrument is the German-led extended ROentgen Survey with an Imaging Telescope Array (eROSITA), a 7-module X-ray telescope system that covers the energy range from 0.2-12 keV. The complementary instrument is the Russian-led Astronomical Roentgen Telescope -- X-ray Concentrator (ART-XC or ART), a 7-module X-ray telescope system that provides higher energy coverage, up to 30 keV (with limited sensitivity above 12 keV).

  12. ["The future must look to the past"* : Prof. Dr. Abraham Aaron Buschke (1868-1943) and Wilhelm Ludwig Löwenstein (1895-1959)].

    PubMed

    Dräger, D L; Protzel, C; Hakenberg, O W

    2015-11-01

    Like many other areas of medicine, dermatology with its comparatively high proportion of Jewish physicians was also not spared from the National Socialist appointment policy with dismissals, laws on "appreciation of the people", research influenced by National Socialist policies, and persecution of Jewish physicians. Prof. Abraham Aaron Buschke and Dr. Wilhelm Ludwig Lowenstein, who were the first to describe the Buschke-Lowenstein tumor, also suffered this destiny. In March 1933, Professor Buschke was dismissed from the position of directing physician at the Virchow Hospital in Berlin and in 1934 his teaching license was revoked. Despite affidavits of his "loyalty to the regime", Dr. Lowenstein fared the same treatment. PMID:26450094

  13. Development of mirror modules for the ART-XC instrument aboard the Spectrum-Roentgen-Gamma mission

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Ramsey, B.; O'Dell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.; Atkins, C.; Zavlin, V.

    2013-09-01

    The Marshall Space Flight Center (MSFC) is developing x-ray mirror modules for the ART-XC instrument on board the Spectrum-Roentgen Gamma Mission. Four of those modules are being fabricated under a Reimbursable Agreement between NASA and the Russian Space Research Institute (IKI.) An additional three flight modules and one spare for the ART-XC Instrument are produced under a Cooperative Agreement between NASA and IKI. The instrument will consist of seven co-aligned x-ray mirror modules with seven corresponding CdTe focal plane detectors. Each module consists of 28 nested thin Ni/Co shells giving an effective area of 65 cm2 at 8 keV, response out to 30 keV, and an angular resolution of 45 arcsec or better HPD. Delivery of the first four modules is scheduled for November 2013, while the remaining three modules will be delivered to IKI in January 2014. We present a status of the ART x-ray module development at MSFC.

  14. [Radiation protection in orthopaedics: implications for clinical practice of the new regulations governing roentgen ray irradiation and radioprotection].

    PubMed

    Nestle, U; Berlich, J

    2006-05-01

    In 2001 or 2002, the legislator made substantial alterations to the "Röntgenverordnung" [regulations governing use of roentgen ray radiation] and "Strahlenschutzverordnung" [regulations governing radiation protection]. This was done to bring German law in line with EU Directives 96/29/Euratom (basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation) and 97/43/Euratom (health protection of individuals against the dangers of ionizing radiation in relation to medical exposure). Proper use of radiation in medicine requires that those involved in its application are aware of the biological effects of radiation. When staff and others are protected good organization and appropriate technology at the workplace can achieve a great deal. In the new directives, the radiation protection for the patient is quantified and the responsibility of the physician is clearly pointed out. The most important aim is uniform quality throughout Europe in radiological diagnosis and radiation protection. PMID:16622706

  15. Development of Mirror Modules for the ART-XC Instrument aboard the Spectrum-Roentgen-Gamma Mission

    NASA Technical Reports Server (NTRS)

    Gubarev, M; Ramsey, B.; O'Dell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.; Atkins, C.; Zavlin, V.

    2013-01-01

    The Marshall Space Flight Center (MSFC) is developing x-ray mirror modules for the ART-XC instrument on board the Spectrum-Roentgen Gamma Mission. Four of those modules are being fabricated under a Reimbursable Agreement between NASA and the Russian Space Research Institute (IKI.) An additional three flight modules and one spare for the ART-XC Instrument are produced under a Cooperative Agreement between NASA and IKI. The instrument will consist of seven co-aligned x-ray mirror modules with seven corresponding CdTe focal plane detectors. Each module consists of 28 nested thin Ni/Co shells giving an effective area of 65 cm2 at 8 keV, response out to 30 keV, and an angular resolution of 45 arcsec or better HPD. Delivery of the first four modules is scheduled for November 2013, while the remaining three modules will be delivered to IKI in January 2014. We present a status of the ART x-ray module development at MSFC.

  16. Comparing precision of distortion-compensated and stereophotogrammetric Roentgen analysis when monitoring fusion in the cervical spine.

    PubMed

    Leivseth, Gunnar; Kolstad, Frode; Nygaard, Oystein P; Zoega, Björn; Frobin, W; Brinckmann, P

    2006-06-01

    Two methods to measure sagittal plane segmental motion in the cervical spine are compared. Translational and rotational motion was measured in nine cervical motion segments of nine patients by distortion-compensated (DCRA) as well as by stereophotogrammetric Roentgen analysis (RSA). To compare measurement precision of the new DCRA protocol with the established RSA technique under realistic clinical conditions and to discuss advantages and disadvantages of both methods in clinical studies. RSA constitutes the most precise method available to assess segmental motion or to monitor fusion in the cervical spine. Due to the invasive nature of the procedure there is an interest in alternative, non-invasive protocols, based on conventional, lateral radiographic views. In nine patients, segmental motion of nine cervical segments with spinal surgery and fusion had previously been assessed from stereo views by RSA. From the archive radiographs, sagittal plane segmental motion was re-assessed by DCRA. Results for sagittal plane translational and rotational motion obtained by both methods are compared. With respect to RSA, sagittal plane rotation was determined by DCRA with an error of 2.4 degrees and a mean difference not significantly different from zero. Sagittal plane translation was determined by DCRA with an error of less than 0.78 mm and a mean difference not significantly different from zero. As two methods are compared, these errors represent the combined (propagated) errors of RSA and DCRA. Averaged over the cohort investigated, measurement of sagittal plane segmental motion exhibited no significant difference between DCRA and RSA. PMID:16163513

  17. Development of a model-based Roentgen stereophotogrammetric analysis system to measure polyethylene wear in unicompartmental arthroplasty.

    PubMed

    Simpson, D J; Kendrick, B J L; Kaptein, B L; Price, A J; Murray, D W; Gill, H S

    2010-11-01

    One of the most important causes of failure in unicompartmental knee replacement (UKR) is polyethylene wear. The aim of this study was to develop and assess a novel Roentgen stereophotogrammetric analysis (RSA)-based method for the measurement of linear wear suitable for UKR. Model-based RSA was used to estimate the linear wear of polyethylene bearings in UKR. A phantom was used to validate the method using in vitro measured bearing thicknesses and the linear wear of ten control bearings was estimated in vivo. Computer aided design (CAD) models for the UKRs were used in the model-based RSA system. There was no statistically significant difference between the estimated and measured bearing thicknesses using the CAD models (p = 0.386). The precision of the linear wear measurement, expressed as the standard deviation of the difference between the estimated and measured bearing thickness was 0.163 mm. The bias (mean difference) was 0.030 mm. The use of RSA to measure in vivo wear in a UKR has been shown to be accurate in a phantom, and has been verified with in vivo measured controls. The technique does not require surgical implantation of marker balls and can be used retrospectively. PMID:21218686

  18. Migration of radio-opaque markers injected into tendon grafts: a study using roentgen stereophotogrammetric analysis (RSA).

    PubMed

    Smith, Conrad Kay; Hull, M L; Howell, S M

    2005-10-01

    An increase in anterior laxity following reconstruction of the anterior cruciate ligament (ACL) can result from lengthening of the graft construct either at the sites of fixation and/or between the sites of fixation (i.e., graft substance). Roentgen stereophotogrammetric analysis (RSA), which requires that radio-opaque markers be attached to the graft, has been shown to be a useful technique in determining lengthening in these regions. Previous methods have been used for attaching radio-opaque markers to the graft, but they all have limitations particularly for single-loop grafts. Therefore, the objective of this study was to evaluate injecting markers directly into the substance of a tendon as a viable method for measuring lengthening of single-loop graft constructs by determining the maximum amount of migration after cyclic loading. Tantalum spheres of 0.8 mm diameter were used as tendon markers. Ten single-loop tendon grafts were passed through tibial tunnels drilled in calf tibias and fixed with a tibial fixation device. Two tendon markers were inserted in one tendon bundle of each graft and the grafts were cyclically loaded for 225,000 cycles from 20 N to 170 N. At specified intervals, simultaneous radiographs were obtained of the tendon markers. Marker migration was computed as the change in distance between the two tendon markers parallel to the axis of the tibial tunnel. Marker migration had a root mean square (RMS) value of less than 0.1 mm. Because the RMS value indicates the error introduced into measurements of lengthening and because this error is negligible, the method described for attaching markers to single-loop ACL grafts has the potential to be useful for determining lengthening of single-loop ACL graft constructs in in vivo studies in humans. PMID:16248321

  19. Lengthening of a single-loop tibialis tendon graft construct after cyclic loading: a study using Roentgen stereophotogrammetric analysis.

    PubMed

    Smith, Conrad Kay; Hull, M L; Howell, S M

    2006-06-01

    Although single-loop tibialis tendon allografts have increased in popularity owing to their many advantages over patellar tendon and double-loop hamstring tendon autografts, some percentage of the patient population do not have clinically stable knees following anterior cruciate ligament reconstruction with single-loop tibialis tendon allografts. Therefore, it would be advantageous to determine the causes of increased anterior laxity which ultimately must be traced to lengthening of the graft construct. One objective of this study was to demonstrate the feasibility of using Roentgen stereophotogrammetric analysis (RSA) to determine the causes of lengthening of a single-loop graft construct subjected to cyclic loading. A second objective was to determine which cause(s) contributes most to an increase in length of this graft construct. Radio-opaque markers were inserted into ten grafts to measure the lengthening at the sites of the tibial and femoral fixations and between the sites of fixation. Each graft was passed through a tibial tunnel in a calf tibia, looped around a rigid cross-pin, and fixed to the tibia with a Washerloc fixation device. The grafts were cyclically loaded for 225,000 cycles from 20 to 170 N. Prior to and at intervals during the cyclic loading, simultaneous radiographs were taken. RSA was used to determine the three-dimensional coordinates of the markers from which the lengthening at the sites of fixation and between the sites of fixation was computed at each interval. The sites of the femoral and tibial fixations were the largest contributors to the increase in length of the graft construct, with maximum average values of 0.68 and 0.55 mm, respectively, after 225,000 cycles. The graft substance between the sites of fixation contributed least to lengthening of the graft, with a maximum average value of 0.31 mm. Ninety percent of the maximum average values occurred before 100,000 cycles of loading for the largest contributors. RSA proved to be a useful method for measuring lengthening due to all three causes. Lengthening of the graft construct at the sites of both fixations is sufficiently large that the combined contributions may manifest as a clinically important increase in anterior laxity. PMID:16706593

  20. Improvement in the clinical practicability of roentgen stereophotogrammetric analysis (RSA): free from the use of the dual X-ray equipment.

    PubMed

    Shih, Kao-Shang; Lee, Chian-Her; Syu, Ci-Bin; Lai, Jiing-Yih; Chen, Kuo-Jen; Lin, Shang-Chih

    2012-10-01

    After total knee replacement, the monitoring of the prosthetic performance is often done by roentgenographic examination. However, the two-dimensional (2D) roentgen images only provide information about the projection onto the anteroposterior (AP) and mediolateral (ML) planes. Historically, the model-based roentgen stereophotogrammetric analysis (RSA) technique has been developed to predict the spatial relationship between prostheses by iteratively comparing the projective data for the prosthetic models and the roentgen images. During examination, the prosthetic poses should be stationary. This should be ensured, either by the use of dual synchronized X-ray equipment or by the use of a specific posture. In practice, these methods are uncommon or technically inconvenient during follow-up examination. This study aims to develop a rotation platform to improve the clinical applicability of the model-based RSA technique. The rotation platform allows the patient to assume a weight-bearing posture, while being steadily rotated so that both AP and ML knee images can be obtained. This study uses X-ray equipment with a single source and flat panel detectors (FPDs). Four tests are conducted to evaluate the quality of the FPD images, steadiness of the rotation platform, and accuracy of the RSA results. The results show that the distortion-induced error of the FPD image is quite minor, and the prosthetic size can be cautiously calibrated by means of the scale ball(s). The rotation platform should be placed closer to the FPD and orthogonal to the projection axis of the X-ray source. Image overlap of the prostheses can be avoided by adjusting both X-ray source and knee posture. The device-induced problems associated with the rotation platform include the steadiness of the platform operation and the balance of the rotated subject. Sawbone tests demonstrate that the outline error, due to the platform, is of the order of the image resolution (= 0.145 mm). In conclusion, the rotation platform with steady rotation, a knee support, and a handle can serve as an alternative method to take prosthetic images, without the loss in accuracy associated with the RSA method. PMID:23157078

  1. Roentgen Satellite (ROSAT)

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Objectives of NASA's participation in the ROSAT mission are to: a) measure the spatial, spectral, and temporal characteristics of discrete cosmic sources including normal stars, collapsed stellar objects, and active galactic nuclei; b) perform spectroscopic mapping of extended X-ray sources including supernova remnants, galaxies, and clusters of galaxies; and c) conduct the above observations of cosmic sources with unprecedented sensitivity and spatial resolution over the 0.1 - 2.0 keV energy band.

  2. Roentgen Satellite (ROSAT)

    NASA Technical Reports Server (NTRS)

    1986-01-01

    As result of the Challenger accident, the alternative possibility for launch of the ROSAT mission with an Atlas/Centaur launch vehicle is being considered. An overview of the problems involved in having the ROSAT flight ready for either a Shuttle or Atlas/Centaur launch is presented.

  3. Roentgen stereophotogrammetric analysis methods for determining ten causes of lengthening of a soft-tissue anterior cruciate ligament graft construct.

    PubMed

    Smith, Conrad; Hull, M L; Howell, S M

    2008-08-01

    There are many causes of lengthening of an anterior cruciate ligament soft-tissue graft construct (i.e., graft+fixation devices+bone), which can lead to an increase in anterior laxity. These causes can be due to plastic deformation andor an increase in elastic deformation. The purposes of this in vitro study were (1) to develop the methods to quantify eight causes (four elastic and four plastic) associated with the tibial and femoral fixations using Roentgen stereophotogrammetric analysis (RSA) and to demonstrate the usefulness of these methods, (2) to assess how well an empirical relationship between an increase in length of the graft construct and an increase in anterior laxity predicts two causes (one elastic and one plastic) associated with the graft midsubstance, and (3) to determine the increase in anterior tare laxity (i.e., laxity under the application of a 30 N anterior tare force) before the graft force reaches zero. Markers were injected into the tibia, femur, and graft in six cadaveric legs whose knees were reconstructed with single-loop tibialis grafts. To satisfy the first objective, legs were subjected to 1500 cycles at 14 Hz of 150 N anterior force transmitted at the knee. Based on marker 3D coordinates, equations were developed for determining eight causes associated with the fixations. After 1500 load cycles, plastic deformation between the graft and WasherLoc tibial fixation was the greatest cause with an average of 0.8+/-0.5 mm followed by plastic deformation between the graft and cross-pin-type femoral fixation with an average of 0.5+/-0.1 mm. The elastic deformations between the graft and tibial fixation and between the graft and femoral fixation decreased averages of 0.3+/-0.3 mm and 0.2+/-0.1 mm, respectively. The remaining four causes associated with the fixations were close to 0. To satisfy the remaining two objectives, after cyclic loading, the graft was lengthened incrementally while the 30 N anterior tare laxity, 150 N anterior laxity, and graft tension were measured. The one plastic cause and one elastic cause associated with the graft midsubstance were predicted by the empirical relationships with random errors (i.e., precision) of 0.9 mm and 0.5 mm, respectively. The minimum increase in 30 N anterior tare laxity before the graft force reached zero was 5 mm. Hence, each of the eight causes of an increase in the 150 N anterior laxity associated with the fixations can be determined with RSA as long as the overall increase in the 30 N anterior tare laxity does not exceed 5 mm. However, predicting the two causes associated with the graft using empirical relationships is prone to large errors. PMID:18601444

  4. Biplane roentgen videometric system for dynamic, 60/sec, studies of the shape and size of circulatory structures, particularly the left ventricle.

    NASA Technical Reports Server (NTRS)

    Ritman, E. L.; Sturm, R. E.; Wood, E. H.

    1973-01-01

    An operator interactive video system for the measurement of roentgen angiographically outlined structures is described. Left ventricular volume and three-dimensional shapes are calculated from up to 200 pairs of diameters measured from ventriculograms at the rate of 60 pairs of biplane images per second. The accuracy and reproducibility of volumes calculated by the system were established by analysis of roentgenograms of inanimate objects of known volume and by comparison of left ventricular stroke volumes calculated by the system with the stroke volumes calculated by an indicator-dilution technique and an aortic root electromagnetic flowmeter. Computer-generated display of the large amounts of data obtained by the videometry system is described.

  5. The Marshall Space Flight Center development of mirror modules for the ART-XC instrument aboard the Spectrum-Roentgen-Gamma mission

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Ramsey, B.; O'Dell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2012-09-01

    The Marshall Space Flight Center (MSFC) is developing x-ray mirror modules for the ART-XC instrument on board the Spectrum-Roentgen-Gamma Mission under a Reimbursable Agreement between NASA and the Russian Space Research Institute (IKI.) ART-XC will consist of seven co-aligned x-ray mirror modules with seven corresponding CdTe focal plane detectors. Currently, four of the modules are being fabricated by the Marshall Space Flight Center (MSFC.) Each MSFC module consist of 28 nested Ni/Co thin shells giving an effective area of 65 cm2 at 8 keV, response out to 30 keV, and an angular resolution of 45 arcsec or better HPD. Delivery of these modules to the IKI is scheduled for summer 2013. We present a status of the ART x-ray modules development at the MSFC.

  6. The Marshall Space Flight Center Development of Mirror Modules for the ART-XC Instrument aboard the Spectrum-Roentgen-Gamma Mission

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail V.; Ramsey, B.; ODell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2012-01-01

    The Marshall Space Flight Center (MSFC) is developing x-ray mirror modules for the ART-XC instrument on board the Spectrum-Roentgen Gamma Mission under a Reimbursable Agreement between NASA and the Russian Space Research Institute (IKI.) ART-XC will consist of seven co-aligned x-ray mirror modules with seven corresponding CdTe focal plane detectors. Currently, four of the modules are being fabricated by the Marshall Space Flight Center (MSFC.) Each MSFC module consist of 28 nested Ni/Co thin shells giving an effective area of 65 sq cm at 8 keV, response out to 30 keV, and an angular resolution of 45 arcsec or better HPD. Delivery of these modules to the IKI is scheduled for summer 2013. We present a status of the ART x-ray modules development at the MSFC.

  7. 'On mind-blindness (optic agnosia)', a classical clinico-pathological report, and its author Wilhelm von Stauffenberg (1879-1918).

    PubMed

    Danek, A

    1996-08-01

    Two photographs from the beginning of our century still instructively illustrate the phenomenon of visual agnosia: the perplexed face of an old lady confronted with objects clears after touching them. This patient with bilateral posterior cerebral infarction was followed for seven years at the Munich Medicine Department of Friedrich von Müller (1858-1941) who had a strong interest in neurology. His assistant Wilhelm von Stauffenberg (1879-1918) reported the case in great detail, including anatomical analysis performed under Constantin von Monakow (1853-1930). Promoted to "Privatdozent" in 1913 on the basis of this report, Stauffenberg's work included several additional, similarly extensive clinico-anatomical case studies but was not limited to problems of cerebral localisation. Under the influence of the Burghölzli group in Zürich he started to practice psychotherapy. Stauffenberg, deeply interested also in the arts and in literature, was the physician of the poet Rainer Maria Rilke (1875-1926) from 1914. He succumbed to pneumonia in 1918. PMID:11619040

  8. [Experiences with the "short arc motion" protocol for rehabilitation of extensor tendon injuries in zones E and F according to Wilhelm].

    PubMed

    Kalb, K; Prommersberger, K-J

    2008-06-01

    Rehabilitation of extensor tendon injuries in zones E and F (according to Wilhelm) is difficult because of the broad bone-tendon interface favouring adhesions. Therefore RB Evans developed the so called "short arc motion" protocol to improve the results of extensor tendon injuries in zones E and F. This protocol consists of immobilisation of the PIP and DIP joints of the injured finger interrupted by regularly performed limited active motion exercises according to the principle of "minimal active tension". Evans demonstrated superior results using this protocol compared to pure immobilisation. In this study we retrospectively evaluated our results using the "short arc motion" regime in isolated extensor tendon injuries since 2000. 10 patients could be examined with a mean follow-up of 2 years and 5 months after operative treatment of fresh extensor tendon injuries as well as one patient with an old extensor tendon lesion. According to the Strickland-Glogovac formula our patients with fresh extensor tendon lesions had 70.3 % on average which is a good result. Using the Geldmacher score these patients had a mean result of 20.7 points indicating a good result too. With regard to the PIP joint, the mean extension deficit was 8.5 degrees. So our results are good, but not as good as those from Evans. Being aware of the limitations of a retrospective study lacking a control group of patients with traditional aftercare, we will continue to use the SAM protocol in our hospital. PMID:18543159

  9. Measurement of migration of soft tissue by modified Roentgen stereophotogrammetric analysis (RSA): validation of a new technique to monitor rotator cuff tears.

    PubMed

    Cashman, P M M; Baring, T; Reilly, P; Emery, R J H; Amis, A A

    2010-04-01

    The purpose of this study was to develop a technique to use Roentgen stereophotogrammetric analysis (RSA) to measure migration of soft-tissue structures after rotator cuff repair. RSA stereo films were obtained; images were analysed using a semi-automatic software program allowing 3D viewing of results. RSA imaging experiments were performed to validate the technique, using a glass phantom with implanted RSA beads and an animal model with steel sutures as RSA markers which were moved known distances. Repeated measurements allowed assessment of inter- and intra-observer variability at a maximum of 1.06 mm. RSA analysis of the phantom showed a variation up to 0.22 mm for static and 0.28 mm for dynamic studies. The ovine tissue specimen demonstrated that using steel sutures as RSA markers in soft tissue is feasible, although less accurate than when measuring bone motion. This novel application of RSA to measure soft tissue migration is practicable and can be extended to in vivo studies. PMID:20143960

  10. A new technique using roentgen stereophotogrammetry to measure changes in the spatial conformation of bovine hind claws in response to external loads.

    PubMed

    Ouweltjes, W; Gussekloo, S W S; Spoor, C W; van Leeuwen, J L

    2016-02-01

    Claw and locomotion problems are widespread in ungulates. Although it is presumed that mechanical overload is an important contributor to claw tissue damage and impaired locomotion, deformation and claw injury as a result of mechanical loading has been poorly quantified and, as a result, practical solutions to reduce such lesions have been established mostly through trial and error. In this study, an experimental technique was developed that allowed the measurement under controlled loading regimes of minute deformations in the lower limbs of dissected specimens from large ungulates. Roentgen stereophotogrammetric analysis (RSA) was applied to obtain 3D marker coordinates with an accuracy of up to 0.1 mm with optimal contrast and to determine changes in the spatial conformation. A force plate was used to record the applied forces in three dimensions. The results obtained for a test sample (cattle hind leg) under three loading conditions showed that small load-induced deformations and translations as well as small changes in centres of force application could be measured. Accuracy of the order of 0.2-0.3 mm was feasible under practical circumstances with suboptimal contrast. These quantifications of claw deformation during loading improve understanding of the spatial strain distribution as a result of external loading and the risks of tissue overload. The method promises to be useful in determining load-deformation relationships for a wide variety of specimens and circumstances. PMID:26654846

  11. Does highly cross-linked polyethylene wear less than conventional polyethylene in total hip arthroplasty? A double-blind, randomized, and controlled trial using roentgen stereophotogrammetric analysis.

    PubMed

    Glyn-Jones, Sion; Isaac, Sherif; Hauptfleisch, Jennifer; McLardy-Smith, Peter; Murray, David W; Gill, Harinderjit Singh

    2008-04-01

    A prospective double-blind, randomized, and controlled trial was conducted using roentgen stereophotogrammetric analysis; 54 total hip arthroplasty patients were randomized to receive either highly cross-linked polyethylene (HXLPE) or standard ultra-high-molecular-weight polyethylene (UHMWPE) liners. The 3-dimensional penetration of the liner was determined over 2 years. For the first 3 months, both polyethylene types had a rapid penetration rate (HXLPE: 0.22 mm, SD = 0.17 mm; UHMWPE: 0.21 mm, SD = 0.15 mm; P = .78). After 3 months, the HXLPE penetration rate (0.06 mm/y, SD = 0.06 mm/y) was significantly lower than the UHMWPE penetration rate (0.10 mm/y, SD = 0.07 mm/y; P = .04). The penetration in the first 3 months was probably caused by creep or bedding in; from 3 months onward, much of the penetration was probably caused by wear. We conclude that HXLPE has a 40% lower wear rate as compared with UHMWPE, suggesting that it will perform better in the long term. PMID:18358369

  12. Soft x-ray calibration of the Co/C multilayer mirrors for the Objective Crystal Spectrometer on the Spectrum Roentgen-Gamma satellite

    NASA Astrophysics Data System (ADS)

    Abdali, Salim; Tarrio, Charles; Christensen, Finn E.; Schnopper, Herbert W.

    1996-07-01

    The objective crystal spectrometer (OXS) on the forthcoming Spectrum-Roentgen-Gamma satellite is designed to carry three kinds of crystals: LiF(220), Si(111) and RAP(001), placed in front of the SODART telescope. Thirty six super polished (RMS roughness < 0.1nm) Si(111) substrates were coated with 65-80 periods of Co/C multilayers using electron beam evaporation deposition combined with ion polishing for the metal layers. These crystals are to be used in the energy band immediately below the C-K absorption edge of 0.284 keV. Because the crystals are to be assembled as one crystal on the OXS, the reflectivity performance as a function of energy and angle of incidence of all crystals has been measured using line radiation from an x-ray tube which provides 1.487 keV and 0.277 keV and using synchrotron radiation from 0.16 keV to 0.28 keV at the Synchrotron Ultraviolet Radiation electron storage ring a t the National Institute of Standards and Technology. The results from these measurements are discussed.

  13. [The alphabet of nature and the alphabet of culture in the eighteenth century. botany, diplomatics, and ethno-linguistics according to Carl von Linné, Johann Christoph Gatterer, and Christian Wilhelm Büttner : Botany, Diplomatics, and ethno-linguistics according to Carl von Linné, Johann Christoph Gatterer, and Christian Wilhelm Büttner].

    PubMed

    Gierl, Martin

    2010-01-01

    In the middle of the eighteenth century, Carl von Linné, Johann Christoph Gatterer, and Christian Wilhelm Büttner attempted to realize the old idea of deciphering the alphabet of the world, which Francis Bacon had raised as a general postulate of science. This article describes these attempts and their interrelations. Linné used the model of the alphabet to classify plants according to the characters of this fruiting body. Gatterer, one of the leading German historians during the Enlightenment, adopted the botanical method of classification by genus and species to classify the history of scripts. He used the forms of the alphabetic characters to measure the age of manuscripts and to map the process of history as a genealogy of culture. Gatterer collaborated closely with Büttner, the first Göttingen professor of natural history. Büttner constructed a general alphabet of languages which connected the phonetics of language with the historically known alphabets. Early on, diplomatics and ethnography combined the natural order of natural history and the cultural order of the alphabet with the attempt to register development and to document development by the evolution of forms. Based on the shared model of the alphabet and on the common necessity to classify their empirical material, natural history and the description of culture were related attempts in the middle of the eighteenth century to comprehend the alphabetically organized nature and a naturally ordered culture. PMID:20665241

  14. [The search for "od." Karl Ludwig Freiheer von Reichenbach (1788-1869) and Karl Wilhelm Mayrhofer (1806-1853), two joined against Justus von Liebig].

    PubMed

    Habacher, M

    1980-05-01

    The author describes the controversy between Justus von Liebig on one side and Reichenbach and Mayrhofer on the other side. It is a controversy about problems of science and medicine which are characteristic for the late 18th and the first half of the 19th century, when Mesmerism and similar ideas of occultic and comparative phenomenona were discussed and often refused as being "not scientific". Justus von Liebig and Karl Ludwig Freiherr von Reichenbach were both chemists, both interested in scientific progress and working in this field. They were friends in the years 1830 to 1848. But later on this friendship ended when Reichenbach--who in the mean time moved to Vienna--became more and more interested in phenomenons seen by sensitive persons concerning effects of light. Although Reichenbach himself was not able to recognize the phenomenons he was sure that other persons had this ability. He had the impression that there is a special force floating through the universe, and this force he called "od". Liebig, who was not able to follow this theory and rejected it has speculation, turned against Reichenbach in 1852-3. So the controversy began and their old friendship came to an end. Reichenbach's theory of the "od", characteristic for the time of the romanticism and leading back to Mesmerism was accepted and supported by the Austrian physician Dr. Karl Wilhelm Mayrhofer who had aroused his interest by describing similar phenomenos some of this patients had. The letters of both men, the chemist and the doctor, which are well preserved (Technical Museum of Vienna) and discussed here, give a good impression of Reichenbach's ideas concerning his theory of the "od" and his philosophical ideas. As Reichenbach tried to find a philosophy corresponding to his theory and as he meant to have found this in the philosophy of Friedrich Eduard Beneke his remarks in those letters give a good information about Beneke's discussion of Reichenbach's theory. Mayrhofer, on the other hand, following Reichenbach's theory of the "od", rejected Beneke's philosophy because he himself joined another philisophy on the basis of the christian religion. However, when Reichenbach's latest book on these problems appeared in 1854, Beneke and Mayrhofer had died shortly before and no further discussion was possible. But Reichenbach's theory, based on the ideas of Mesmerism, and the controversial discussion about new explanations of the phenomenona seen by sensitive persons are characteristic for this time and also for our time as such perceptions are not entirely denied but thought over in a new way. PMID:6156792

  15. Wer war Heinrich Wilhelm Dove? [Who was Heinrich Wilhelm Dove?

    NASA Astrophysics Data System (ADS)

    Posch, Thomas

    2005-09-01

    Heinrich W. Dove was born in Liegnitz (Legnica) in 1803 and died in 1879 in Berlin. In the early 1820s, he studied in Breslau (Wroclaw) and Berlin. He also studied with the famous philosopher G. W. F. Hegel. In 1845, Dove became full professor of physics in Berlin. Dove was one of the founders of meteorology and weather forecast. The present article presents a summary of his life and his works.

  16. Predicting 3D pose in partially overlapped X-ray images of knee prostheses using model-based Roentgen stereophotogrammetric analysis (RSA).

    PubMed

    Hsu, Chi-Pin; Lin, Shang-Chih; Shih, Kao-Shang; Huang, Chang-Hung; Lee, Chian-Her

    2014-12-01

    After total knee replacement, the model-based Roentgen stereophotogrammetric analysis (RSA) technique has been used to monitor the status of prosthetic wear, misalignment, and even failure. However, the overlap of the prosthetic outlines inevitably increases errors in the estimation of prosthetic poses due to the limited amount of available outlines. In the literature, quite a few studies have investigated the problems induced by the overlapped outlines, and manual adjustment is still the mainstream. This study proposes two methods to automate the image processing of overlapped outlines prior to the pose registration of prosthetic models. The outline-separated method defines the intersected points and segments the overlapped outlines. The feature-recognized method uses the point and line features of the remaining outlines to initiate registration. Overlap percentage is defined as the ratio of overlapped to non-overlapped outlines. The simulated images with five overlapping percentages are used to evaluate the robustness and accuracy of the proposed methods. Compared with non-overlapped images, overlapped images reduce the number of outlines available for model-based RSA calculation. The maximum and root mean square errors for a prosthetic outline are 0.35 and 0.04 mm, respectively. The mean translation and rotation errors are 0.11 mm and 0.18°, respectively. The errors of the model-based RSA results are increased when the overlap percentage is beyond about 9%. In conclusion, both outline-separated and feature-recognized methods can be seamlessly integrated to automate the calculation of rough registration. This can significantly increase the clinical practicability of the model-based RSA technique. PMID:25293422

  17. Can markers injected into a single-loop anterior cruciate ligament graft define the axes of the tibial and femoral tunnels? A cadaveric study using roentgen stereophotogrammetric analysis.

    PubMed

    Smith, Conrad; Hull, M L; Howell, S M

    2008-08-01

    Lengthening of a soft-tissue anterior cruciate ligament (ACL) graft construct over time, which leads to an increase in anterior laxity following ACL reconstruction, can result from relative motions between the graft and fixation devices and between the fixation devices and bone. To determine these relative motions using Roentgen stereophotogrammetry (RSA), it is first necessary to identify the axes of the tibial and femoral tunnels. The purpose of this in vitro study was to determine the error in using markers injected into the portions of a soft-tissue tendon graft enclosed within the tibial and femoral tunnels to define the axes of these tunnels. Markers were injected into the tibia, femur, and graft in six cadaveric legs the knees of which were reconstructed with single-loop tibialis grafts. The axes of the tunnels were defined by marker pairs that were injected into the bones on lines parallel to the walls of the tibial and femoral tunnels (i.e., standard). By using marker pairs injected into the portions of the graft enclosed within the tibial and femoral tunnels and the marker pairs aligned with the tunnel axes, the directions of vectors were determined by using RSA, while a 150 N anterior force was transmitted at the knee. The average and standard deviations of the angle between the two vectors were 5.5+/-3.3 deg. This angle translates into an average error and standard deviation of the error in lengthening quantities (i.e., relative motions along the tunnel axes) at the sites of fixation of (0.6+/-0.8)%. Identifying the axes of the tunnels by using marker pairs in the graft rather than marker pairs in the walls of the tunnels will shorten the surgical procedure by eliminating the specialized tools and time required to insert marker pairs in the tunnel walls and will simplify the data analysis in in vivo studies. PMID:18601465

  18. Beer, Wilhelm (1797-1850)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Berlin banker and amateur astronomer, collaborated with JOHANN MDLER in a map of the Moon, in its organization following closely the plan laid out by the less well known selenographer W G LOHRMANN. Suggested with Mdler in 1837 the advantages of an observatory on the Moon (continuous observation over a 14 day lunar night, for example: they did not know that there is no lunar atmosphere so that s...

  19. A new tibial coordinate system improves the precision of anterior-posterior knee laxity measurements: a cadaveric study using Roentgen stereophotogrammetric analysis.

    PubMed

    Roos, P J; Neu, C P; Hull, M L; Howell, S M

    2005-03-01

    Roentgen stereophotogrammetric analysis (RSA) can be used to measure changes in anterior-posterior (A-P) knee laxity after anterior cruciate ligament (ACL) reconstruction. Previous measurements of A-P knee laxity using RSA have employed a tibial coordinate system with the origin placed midway between the tips of the tibial-eminences. However, the precision in measuring A-P knee laxity might be improved if the origin was placed on the flexion-extension axis of rotation of the knee. The purpose of this study was to determine whether a center-of-rotation tibial coordinate system with the origin placed midway between the centers of the posterior femoral condyles, which closely approximates the flexion-extension center-of-rotation of the knee, improves the precision in measuring A-P knee laxity compared to the tibial-eminence-based coordinate system. A-P knee laxity was measured using each coordinate system six times in three human cadaveric knees implanted with 0.8-mm diameter tantalum markers. For each laxity measurement, the knee was placed in a custom loading apparatus and biplanar radiographs were obtained while the knee resisted a 44 N posterior shear force and 136 N anterior shear force. A-P knee laxity was determined from the change in position of the tibia, with respect to the femur, resulting from the posterior and anterior shear forces. The precision for each coordinate system was calculated as the pooled standard deviation of A-P knee laxity measurements. The precision of the center-of-rotation coordinate system was 0.33 mm, which was about a factor of 2 better than the 0.62 mm precision of the tibial-eminence coordinate system (p=0.006). The 0.33 mm precision with the center-of-rotation coordinate system suggests that an observed change of either 0.56 mm (i.e. 1.7 standard deviations) or greater in A-P knee laxity over time is a real change and not due to measurement error when the new tibial coordinate system is used and other factors contributing to variability are controlled as was done in this study. Accordingly, clinicians and researchers should consider the use of this alternate tibial coordinate system when making serial measurements of A-P knee laxity using RSA because the improved precision allows for the observation of smaller differences. PMID:15734244

  20. Neuropathological research at the "Deutsche Forschungsanstalt fuer Psychiatrie" (German Institute for Psychiatric Research) in Munich (Kaiser-Wilhelm-Institute). Scientific utilization of children's organs from the "Kinderfachabteilungen" (Children's Special Departments) at Bavarian State Hospitals.

    PubMed

    Steger, Florian

    2006-09-01

    During National Socialism, the politically motivated interest in psychiatric genetic research lead to the founding of research departments specialized in pathological-anatomical brain research, the two Kaiser Wilhelm-Institutes (KWI) in Berlin and Munich. The latter was indirectly provided with brain material by Bavarian State Hospitals, to three of which "Kinderfachabteilungen" (Special Pediatric Units) were affiliated. As children became victims of the systematically conducted child "euthanasia" in these Special Pediatric Units, this paper will address the question whether and to which extent the organs from victims of child "euthanasia" were used for (neuro-) pathological research at the KWI in Munich. By means of case studies and medical histories (with focus on the situation in Kaufbeuren-Irsee), I will argue that pediatric departments on a regular base delivered slide preparations, that the child "euthanasia" conduced in these departments systematically contributed to neuropathological research and that slide preparations from victims of child "euthanasia" were used in scientific publications after 1945. PMID:16887759

  1. ["... that progress in anatomy is most likely to occur when its problems include the study of growth and function, as well as of structure". about the anatomy and physiology of Ernst Heinrich Weber (794-1878 and Wilhelm His (1831-1904) his successor in the department of anatomy at the University of Leipzig].

    PubMed

    Hildebrand, Reinhard

    2005-11-01

    The Leipzig anatomist and physiologist Ernst Heinrich Weber had introduced physiological thinking in anatomy and exact methods of mathematical physics to the study of the functioning of the body making him the founder of a physically orientated physiology. But he would not have been that excellent physiologist without being a nonetheless distinguished anatomist since he solved his physiological problems usually following function in close relation to structure. Together with his brother Wilhelm Eduard Weber (1804-1891), who later was to become a famous physicist, in their theory of waves he laid the basis for an exact analysis of the movements of fluids in elastic tubes und was the first to apply the basic laws of hydrodynamics to the circulation of the blood. In collaboration with his youngest brother Eduard Friedrich Wilhelm Weber (1806-1871), who worked as a prosector at his institute and together with Wilhelm Weber had studied the mechanics of the walking apparatus, he demonstrated the inhibiting effect of the vagus nerve on the action of the heart. Ernst Heinrich Weber's approach to consider an organ as a whole not neglecting the study of its function set him apart from most of his contemporaries and has characterized the work of the Leipzig anatomists and physiologists since his time. Among those was Wilhelm His from Basle who succeeded him in the chair of anatomy in 1872. On the basis of a systematic analysis of human embryos by means of serial sections and plastic reconstruction His completely reformed the field of embryology and was the first to present a comprehensive treatise on human embryology. The making of modern human embryology was, above all, his achievement. He did not confine himself to mere description but wanted to gain deeper insight into the causal events by developmental-mechanical conceptions. With his detection of the neuroblasts and that they give rise to an axon and later to dendrites His provided the developmental foundations for the neuron-theory. PMID:16320825

  2. The Alphabet of Nature and the Alphabet of Culture in the Eighteenth Century. Botany, Diplomatics, and Ethno-Linguistics according to Carl von Linné, Johann Christoph Gatterer, and Christian Wilhelm Büttner

    PubMed Central

    2010-01-01

    In the middle of the eighteenth century, Carl von Linné, Johann Christoph Gatterer, and Christian Wilhelm Büttner attempted to realize the old idea of deciphering the alphabet of the world, which Francis Bacon had raised as a general postulate of science. This article describes these attempts and their interrelations. Linné used the model of the alphabet to classify plants according to the characters of this fruiting body. Gatterer, one of the leading German historians during the Enlightenment, adopted the botanical method of classification by genus and species to classify the history of scripts. He used the forms of the alphabetic characters to measure the age of manuscripts and to map the process of history as a genealogy of culture. Gatterer collaborated closely with Büttner, the first Göttingen professor of natural history. Büttner constructed a general alphabet of languages which connected the phonetics of language with the historically known alphabets. Early on, diplomatics and ethnography combined the natural order of natural history and the cultural order of the alphabet with the attempt to register development and to document development by the evolution of forms. Based on the shared model of the alphabet and on the common necessity to classify their empirical material, natural history and the description of culture were related attempts in the middle of the eighteenth century to comprehend the alphabetically organized nature and a naturally ordered culture. PMID:20665241

  3. Olbers, Heinrich Wilhelm (1758-1840)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Doctor, astronomer, born in Arbergen, Germany, enthusiast for astronomy. He discovered several comets. In 1800 he joined the team of 24 `celestial police', organized by FRANZ VON ZACH, who were to patrol a share of the zodiac looking for the planet missing (according to BODE's law) between Mars and Jupiter. On New Year's Day 1801 PIAZZI discovered Ceres, and, in March 1802, Olbers discovered Pall...

  4. Crystallography: To Infinity and Beyond

    ERIC Educational Resources Information Center

    Bond, Charles

    2014-01-01

    William Henry Bragg moved from Cambridge in Britain to South Australia to take up a professorship at the University of Adelaide in 1885. He brought with him a broad interest in many areas of physics, but when Wilhelm Roentgen discovered X-rays in the 1890s, Bragg's interest was stimulated. William's Australian-born son, Lawrence (WL

  5. Radiation in the universe

    NASA Astrophysics Data System (ADS)

    Stuhlinger, Ernst; Truemper, Joachim; Weisskopf, Martin

    When Wilhelm Conrad Roentgen discovered radiation one hundred years ago, it seemed that what was discovered was one of the rarest and most volatile members of the family of the basic modules of our natural world. Today cosmologists report that a substantial part of the universe's radiation energy consists of X-rays, which travel through cosmic space with the speed of light.

  6. Crystallography: To Infinity and Beyond…

    ERIC Educational Resources Information Center

    Bond, Charles

    2014-01-01

    William Henry Bragg moved from Cambridge in Britain to South Australia to take up a professorship at the University of Adelaide in 1885. He brought with him a broad interest in many areas of physics, but when Wilhelm Roentgen discovered X-rays in the 1890s, Bragg's interest was stimulated. William's Australian-born son, Lawrence (WL…

  7. Radiation in the universe

    NASA Technical Reports Server (NTRS)

    Stuhlinger, Ernst; Truemper, Joachim; Weisskopf, Martin

    1992-01-01

    When Wilhelm Conrad Roentgen discovered radiation one hundred years ago, it seemed that what was discovered was one of the rarest and most volatile members of the family of the basic modules of our natural world. Today cosmologists report that a substantial part of the universe's radiation energy consists of X-rays, which travel through cosmic space with the speed of light.

  8. Validation of a new method for finding the rotational axes of the knee using both marker-based roentgen stereophotogrammetric analysis and 3D video-based motion analysis for kinematic measurements.

    PubMed

    Roland, Michelle; Hull, M L; Howell, S M

    2011-05-01

    In a previous paper, we reported the virtual axis finder, which is a new method for finding the rotational axes of the knee. The virtual axis finder was validated through simulations that were subject to limitations. Hence, the objective of the present study was to perform a mechanical validation with two measurement modalities: 3D video-based motion analysis and marker-based roentgen stereophotogrammetric analysis (RSA). A two rotational axis mechanism was developed, which simulated internal-external (or longitudinal) and flexion-extension (FE) rotations. The actual axes of rotation were known with respect to motion analysis and RSA markers within ± 0.0006 deg and ± 0.036 mm and ± 0.0001 deg and ± 0.016 mm, respectively. The orientation and position root mean squared errors for identifying the longitudinal rotation (LR) and FE axes with video-based motion analysis (0.26 deg, 0.28 m, 0.36 deg, and 0.25 mm, respectively) were smaller than with RSA (1.04 deg, 0.84 mm, 0.82 deg, and 0.32 mm, respectively). The random error or precision in the orientation and position was significantly better (p=0.01 and p=0.02, respectively) in identifying the LR axis with video-based motion analysis (0.23 deg and 0.24 mm) than with RSA (0.95 deg and 0.76 mm). There was no significant difference in the bias errors between measurement modalities. In comparing the mechanical validations to virtual validations, the virtual validations produced comparable errors to those of the mechanical validation. The only significant difference between the errors of the mechanical and virtual validations was the precision in the position of the LR axis while simulating video-based motion analysis (0.24 mm and 0.78 mm, p=0.019). These results indicate that video-based motion analysis with the equipment used in this study is the superior measurement modality for use with the virtual axis finder but both measurement modalities produce satisfactory results. The lack of significant differences between validation techniques suggests that the virtual sensitivity analysis previously performed was appropriately modeled. Thus, the virtual axis finder can be applied with a thorough understanding of its errors in a variety of test conditions. PMID:21599094

  9. [Roentgen findings following incorporation of metallic mercury].

    PubMed

    Lange, H; Schadeberg, A; Hiller, U

    1987-05-01

    In the light of own cases and the present literature the different possibilities of the incorporation of metallic mercury are indicated, the radiological findings explained and the possible consequences of the proof discussed. PMID:3630295

  10. Roentgen Findings in Occipital Pole Tumors

    PubMed Central

    Bilodeau, Larry; Hanafee, William

    1967-01-01

    The arteriographic findings of occipital pole tumors consist of the following: 1. Anterior displacement and elevation of the middle cerebral group. 2. Accordioning of the anterior choroidal artery. 3. Anterior displacement of the lateral branch of the posterior choroidal artery. 4. Local stretching of vessels about the tumor. 5. Onion skinning of the pial vessels. 6. Anterior displacement of the vein of the occipital horn. 7. Greater displacement of the internal cerebral vein than of the anterior cerebral artery. Air studies require precise radiographic technique lest the subtle displacements of the occipital horn and trigone area be missed. ImagesFigure 1.Figure 2.Figure 3.Figure 4. PMID:6044288

  11. Investigation relative to the Roentgen Satellite (ROSAT)

    NASA Technical Reports Server (NTRS)

    Elvis, Martin S.; Primini, Francis A.; Fabbiano, Guiseppina; Harris, Daniel E.; Jones-Foreman, Christine; Trinchieri, Ginevra; Golub, Leon; Bookbinder, Jay; Seward, Frederick D.; Zombeck, Martin V.

    1994-01-01

    Reports include: High Resolution Observations of the Central Region of M31; The X-ray Emission of Low-X-ray-Luminosity Early-Type Galaxies: Gas Versus Compact Sources; Interaction Between Cluster Gas and Radio Features of Cygnus A; Hot Gas and Dark Halos in Early-Type Galaxies; A Gravitational Lens in X-rays - 0957+461; How Massive are Early-Type Galaxies?; Three Crab-Like SNR in the Large Magellanic Cloud; and Soft X-ray Emission from Boundary Layers in Cataclysmic Variables. Papers submitted to the Astrophysical Journal are attached.

  12. Hermann Wilhelm Abich im Kaukasus: Zum zweihundertsten Geburtstag

    NASA Astrophysics Data System (ADS)

    Seibold, Ilse; Seibold, Eugen

    2006-11-01

    Hermann Abich was born in 1806 in Berlin and died in 1886 in Graz. He grew up in a wealthy family which had friendly relations with famous scientists like Alexander von Humboldt, Leopold von Buch or Carl Ritter. After his studies in Heidelberg and Berlin he turned to extended fieldwork at the volcanoes of Italy. In 1833 1834 he published excellent petrological/chemical results and got soon a good scientific reputation. Thus he was nominated as Professor for Geology and Mineralogy of the prestigious Russian University in Dorpat (now Tartu, Esthonia) in 1842. In 1844 he was sent to Armenia by the Russian authorities. For the next three decades his fieldwork with about 190 publications was concentrated on the Great and Lesser Caucasus. This was a period of Russian expansion to the South with long-lasting regional fights. But he enjoyed the support of powerful governors. He was an indefatigable and enthusiastic explorer and a precise observer and designer. His interests covered many fields: morphology, glaciology, structural geology, volcanology with Thermal Springs, mineral resources from hydrocarbons, coal, salt to ores, stratigraphy and paleontology as a base for geological maps. But he also gave advice for practical problems, and he was active in meteorology, botany and archaeology. Alltogether he became “the Father of Caucasus Geology”. The following sketch stresses only on three aspects of his activities. He was one of the first pioneers in hydrocarbon exploration, especially around the anticlines with the mud volcanoes near Baku. In many respects, however, his fundamental ideas were erronous. He explained the structure of the Great Caucasus by the traditional theories of Leopold von Buch and Elie de Beaumont. The Caucasus anticline “was elevated by forces acting from beneath”. Following them he tried to discover regularities in the strike of mountain chains. Similarily he treated volcanism like Alexander von Humboldt and Leopold von Buch with their two groups of phenomena: voluminous, mostly basaltic “elevation craters” versus isolated, mostly trachytic and relatively small cones of “true volcanoes”. In spite of the isolation of the Caucasus region he had cultivated continuously contacts with leading geologists in Europe and was honoured by many institutions. He left Russia in 1876 for Vienna planning to write there the final monograph volumes about his investigations but he died before he could complete them.

  13. [Are conventional roentgen technics for tbc diagnosis still acceptable?].

    PubMed

    Stender, H S; Saure, D

    1991-11-01

    Image quality in chest radiography has to be high enough that even subtle pulmonary abnormalities can be easily visualised. Conventional screen/film radiographs obtained with 200 to 400 speed systems fulfil this requirement well enough. Large screen and slit beam image intensifier systems that have replaced fluoroscopy screens, yield equivalently good results. The amber system and storage phosphor digital radiography systems are efficient alternatives. Radiation exposure is generally low and decreased further if image intensifiers are used. Conventional technique with highly sensitive film/screen combinations has been approved for diagnosis of pulmonary tuberculosis. PMID:1837343

  14. [Roentgen diagnosis of body packers--radiological and forensic considerations].

    PubMed

    Hierholzer, J; Tantow, H; Cordes, M; Mäurer, J; Keske, U; Koch, E; Felix, R

    1995-05-01

    The diagnostic value of abdominal ultrasonography and plain abdominal radiographs for the detection or exclusion of body smugglers was investigated prospectively. Both methods showed equally high sensitivity and specificity in the detection of swallowed drug packages. Possibilities for misinterpretation of physiological abdominal contents are illustrated. In addition to the radiological aspects, the legal implications of the subject are discussed. PMID:7605812

  15. SMPTE Test Pattern For Certification Of Medical Diagnostic Display Devices

    NASA Astrophysics Data System (ADS)

    Lisk, Kenneth G.

    1984-08-01

    Since the invention of x-rays by Wilhelm Conrad Roentgen, rapid advances have been made in the radiological detection of body abnormalities. This was very evident in the 1960's and 70's when the marriage of computers to radiology gave birth to a new generation of imaging modalities such as computerized tomography, ultrasound, digital radiographic imaging, nuclear medicine, and nuclear magnetic resonance. Many of these devices employ digital computer techniques for signal manipulation, and the resultant analog diagnostic images are displayed on television monitors for viewing and on imaging cathode-ray tubes for a photographic hard copy.

  16. [Wilhelm Reich--Arthur Janov--a comparison of their work].

    PubMed

    Sprengler, M

    1984-01-01

    Although he does not always mention it, A. Janov agrees with many of W. Reich's opinions on theoretical-philosophical foundations and the theory of neurosis and other illnesses; from their criticism of society both of them develop the demand for prophylaxis of neurosis as a prerequisit for their common utopia of a selfregulated society. Primal therapy and Orgon therapy are two different forms of the "New Body Therapies" group. The authors disagree with their views of the physiological nature of Pain (A. Janov) and blokked orgon, the "function of the orgasm" and "orgastic potency", concepts that were considered by Reich to be his most important. Possible reasons for the discrepancies are given. PMID:6523964

  17. [Wilhelm Conrad Röntgen: 100 years of the discovery of X-rays].

    PubMed

    Arruda, W O

    1996-09-01

    One hundred years after its discovery, one can hardly conceive the medical practice without the existence of X rays. A brief account of X rays discovery and about it notable discoverer is presented. PMID:9110002

  18. Philosophical Anthropology and Educational Change: Wilhelm Von Humbolt and the Prussian Reforms

    ERIC Educational Resources Information Center

    Thomas, Carla R.

    1973-01-01

    After the defeat by Napoleon, Prussia endeavored to rebuild its war torn country by instituting sweeping social and educational reforms. This effort marked one of the few instances in which philosophical anthropology formed the explicit basis of a successful program of social change. (Author/KM)

  19. [Wilhelm Conrad Röntgen and the discovery of X-rays].

    PubMed

    Tubiana, M

    1996-01-01

    W.C. Röntgen reported the discovery of X-rays in December 1895 after seven weeks of assiduous work during which he had studied the properties of this new type of radiation able to go through screens of notable thickness. He named them X-rays to underline the fact that their nature was unknown. The news of this discovery immediately aroused an immense interest in the public and also initiated intense research in several directions. Physicians and physicists began as early as January 1896 to use X-rays on patients to investigate the skeleton and subsequently the lung and other organs. This was the birth or radiology. Rapidly they observed skin erythema, which led to the idea of using X-rays against a variety of lesions. In June 1896 the first patient was treated by radiotherapy. J.J. Thomson (Cambridge, U.K.) showed that X-rays were able to ionize gaz and the study of this phenomenon led to the discovery of electrons in 1897. In order to understand the emission of X-rays, H. Becquerel (Paris) investigated the role of the phosphorescence of the glass of the tube and while doing so discovered radioactivity in March 1896. X-rays and radioactivity were at the origin of the scientific revolution at the end of the 19th and the beginning of the 20th centuries. Research on radioactive materials demonstrated the existence of atoms which had been till then only a convenient hypothesis for explaining chemical reactions, but whose reality was considered as dubious by most physicists. Moreover, interaction of particles emitted by radionuclides and atoms enabled first the study of the structure of the atom and subsequently its nucleus. Matter, elements which were thought to be immutable were found to be transmutable, and eventually to disintegrate. The origin of the energy transferred to the radiation which was emitted appeared as a mystery and in order to explain it the physicist had to accept that matter could convert energy. In 1903 Einstein established the equivalence between matter and energy. Matter, energy, electricity, light which were formerly considered as continuous quantities were found to be discrete: there are particles of matter (elementary particles), energy (quanta, Planck 1905), electricity (electron), light (photons). Radioactive decay, particle interactions imposed a probabilistic physics which progressively replaced classic deterministic physics. Radioactivity can be used as a clock to measure time in the universe. Datations were made for fossils, art masterpieces and also for the earth, the solar system and universe. X-rays diffraction proved to be a powerful tool for studying crystals and molecules, in particular protein, and in 1953 enabled to demonstrate the DNA double helix. Hence X-rays and radioactivity originated a revolution in physics and science and in the vision of nature. The imperceptible and yet so powerful rays demonstrated the deficiencies of our senses. Mathematical entities and instrumentation must complement our sensations. The huge increment in our knowledge is accompanied by a divorce between the scientist and the layman who now often has great difficulties understanding new concepts not only in physics but also in biology. PMID:8696882

  20. FINAL DISPOSAL OF RADIOACTIVE WASTE IN GERMANY: PLAN APPROVAL PROCESS OF KONRAD MINE AND ACCEPTANCE REQUIREMENTS

    SciTech Connect

    Bandt, Gabriele; Posnatzki, Britta; Beckers, Klaus-Arno

    2003-02-27

    Currently no final repository for any type of radioactive waste is operated in Germany. Preliminary Final Storage Acceptance Requirements for radioactive waste packages were published in 1995. Up to now these are the basis for treatment of radioactive waste in Germany. After licensing of the final repository these preliminary waste acceptance requirements are completed with licensing conditions. Some of these conditions affect the preliminary waste acceptance requirements, e. g. behavior of chemo-toxic substances in case of accidents in the final repository or the allowed maximum concentration of fissile material. The presented examples of radioactive waste conditioning campaigns demonstrate that no difficulties are expected in management, characterization and quality assurance of radioactive wastes due to the licensing conditions.

  1. The Progress of Physics

    NASA Astrophysics Data System (ADS)

    Schuster, Arthur

    2015-10-01

    Introduction; 1. Scope of lectures. State of physics in 1875. Science of energy. Theory of gases. Elastic solid theory of light. Maxwell's theory of electricity. Training of students. Maxwell's view. Accurate measurement and discovery of Argon. German methods. Kirchhoff's laboratory. Wilhelm Weber's laboratory. The two laboratories of Berlin. Laboratory instruction at Manchester. Position of physics in mathematical tripos at Cambridge. Todhunter's views. The Cavendish laboratory. Spectrum analysis. The radiometer. Theory of vortex atom; 2. Action at a distance. Elastic solid of theory of light. Maxwell's theory of electrical action. Electro-magnetic theory. Verification of electromagnetic theory by Hertz. Electro-magnetic waves. Wireless telegraphy. First suggestion of molecular structure of electricity. Early experiments in the electric discharge through gases. Kathode rays. Works of Goldstein and Crookes. Hittorf's investigations. Own work on the discharge through gases. Ionization of gases. Magnetic deflexion of kathode rays. J. J. Thomson's experiments. Measurement of atomic charge; 3. Roentgen's discovery. Theories of Roentgen rays. Ionizing power of Roentgen rays. Conduction of electricity through ionized gases. Discovery of radio-activity. Discovery of radium. Magnetic deflexion of rays emitted by radio-active bodies. Discovery of emanations. Theory of radio-active change. Decay of the atom. Connexion between helium and the a ray. Helium produced by radium. Strutt's researches on helium accumulated in rocks. Electric inertia. Constitution of atom. J. J. Thomson's theory of Roentgen radiation. The Michelson-Morley experiment. Principle of relativity. The Zeeman effect. Other consequences of electron theory. Contrast between old and modern school of physics; 4. Observational sciences. Judgment affected by scale. Terrestrial magnetism. Existence of potential. Separation of internal and external causes. Diurnal variation. Magnetic storms. Their causes. Solar influence. Theories of secular variation. Atmospheric electricity. Negative charge of Earth. Ionization of air. Origin of atmospheric electricity. Electric charge of rain. Ebert's theory. Cause of thunderstorms. The age of the Earth. Rigidity of Earth. Displacement of axis. Gravitation. Identity of molecules of the same kind; Index.

  2. Radiation and health*

    PubMed Central

    Lindell, B.

    1987-01-01

    Radiation has been a source of fascination and concern ever since Wilhelm Konrad Röntgen discovered X-rays on 8 November 1895. Over the years, health workers as well as the public have been concerned about medical uses of X-rays, the presence of radon in buildings, radioactive waste from nuclear power stations, fallout from nuclear test explosions, radioactive consumer products, microwave ovens, and many other sources of radiation. Most recently, the tragic accident at the Chernobyl nuclear power station in the USSR, and the subsequent contamination over most of Europe, has again wakened interest and concern and also reminded us about a number of misconceptions about radiation. This article describes the essentials about radiation (especially ionizing radiation) and its health effects. PMID:3496982

  3. The capability of fluoroscopic systems to determine differential Roentgen-ray absorption

    NASA Technical Reports Server (NTRS)

    Baily, N. A.; Crepeau, R. L.

    1975-01-01

    A clinical fluoroscopic unit used in conjunction with a TV image digitization system was investigated to determine its capability to evaluate differential absorption between two areas in the same field. Fractional contrasts and minimum detectability for air, several concentrations of Renografin-60, and aluminum were studied using phantoms of various thicknesses. Results showed that the videometric response, when treated as contrast, shows a linear response with absorber thickness up to considerable thicknesses.

  4. The Teaching of Roentgen Anatomy to Medical Students: A Self-Instructional Approach

    ERIC Educational Resources Information Center

    Tegtmeyer, Charles J.; And Others

    1974-01-01

    This multidisciplinary approach necessitates the involvement of radiology that is suited for inclusion in an anatomy course since it is an ideal instrument for teaching anatomic principles. (Author/PG)

  5. Total hip replacement with a zirconium oxide ceramic femoral head: a randomised roentgen stereophotogrammetric study.

    PubMed

    von Schewelov, T; Sanzén, L; Onsten, I; Carlsson, A; Besjakov, J

    2005-12-01

    We investigated the wear characteristics and clinical performance of four different total hip joint articulations in 114 patients. Wear and migration was measured by roentgenstereophotogrammetric analysis at five years or at the last follow-up. The mean annual wear was 0.11 mm for a stainless steel/Enduron articulation, 0.34 mm for stainless steel/Hylamer cup, 0.17 mm for zirconium oxide ceramic/Enduron and 0.40 mm for zirconium oxide ceramic/Hylamer. The difference between the groups was significant (p < 0.008) except for stainless steel/Hylamer vs zirconium oxide ceramic/Hylamer (p = 0.26). At present, 12 patients have undergone a revision procedure, four at five years and eight thereafter. No patient who received a stainless steel/Enduron articulation at their primary replacement required revision. Conflicting results have been reported about the performance of the zirconium oxide ceramic femoral head, but our findings suggest that it should not be used with a polymethylmethacrylate acetabular component. Hylamer has already been withdrawn from the market. PMID:16326875

  6. [Use of roentgen-television film for the analysis of physical exercises].

    PubMed

    Kotel'nikova, E G; Istomin, I V

    1975-03-01

    Biochemical investigation of movements of man is based on precise registration of movements of body links in space and time. The popular method of filming is almost unsuitable for studying exact movements in small joints, rotation movements and movements performed simultaneously in several joints. The use of rentgen-television filming of movement in the joints broadens the possibilities of biomechanical investigations of movements of man. PMID:1156177

  7. [Complex treatment of hypertrophic scars using long-wave roentgen radiation].

    PubMed

    Protsenko, T V

    1984-02-01

    The paper is concerned with a therapeutic method for hypertrophic scars including Bucky rays, pyrogenal, vitamins A, E, B12, sodium salicylate and dimexide ointment. Multimodality treatment of hypertrophic scars is effective, well tolerated and can be widely used in out-patient clinics. It makes it possible to reduce the period of therapy by 2-3 mos., and the summary dose by 2000-3000 rad (18.6-27.9 Gy) as compared to common therapy with Bucky rays only. Changes in the connective structure of scars in the process of multimodality therapy are nonspecific and account for some mechanisms of scar regression and reaffirm the efficacy of this therapeutic method. PMID:6700392

  8. Celebrating the First One Hundred Years of The American Physical Society

    NASA Astrophysics Data System (ADS)

    Merzbacher, Eugen

    1998-11-01

    In the past few years physicists have had the occasion to observe a number of centennials: the one hundredth anniversaries of the discoveries of x rays, the electron, and radioactivity, and other milestones. The first Nobel Prize in Physics was given to Wilhelm Conrad Roentgen in 1901. The first meeting of The American Physical Society was held on 20 May 1899 at 10:30 a.m. The centenary of the Society will be celebrated at an extraordinary meeting on 20-26 March, 1999, in Atlanta. All units of the APS - Divisions, Topical Groups, Forums, as well as Sections - will contribute special symposia and exhibits, highlighting the achievements of physicists and the role played by the Society in this century. The Centennial Meeting and the concurrent Festival of Physics in the City of Atlanta are intended to appeal to the entire physics community and to the students, who will carry the torch of science into the next century.

  9. A triboelectric closed loop band system for the generation of x-rays

    NASA Astrophysics Data System (ADS)

    Van Cleve, E.; Lucas, B.; Ganlieli, Z.; Wong, E. W.; Cortes, P.; Mehta, N.; Cuadra, D.; Fong, J.; Hansen, S.; Kotowski, A.; Camara, C. G.

    2015-08-01

    X-ray have been commercially produced using the same basic design since their discovery by Wilhelm Roentgen in 1895, for which he was awarded the first Nobel prize in physics. This technology requires high voltage elements, ultra high vacuum tubes, and high voltage electronics. The vacuum and high voltage drive up the price of x-ray technology and in order to bring down the cost, a brand new way to produce x-rays is needed. In 2008 Carlos Camara, Juan Escobar, Jonathan R. Hird, and Seth Putterman1 discovered that by pealing scotch tape in a vacuum you could create enough x-rays to take an x-ray radiograph of a finger. This lead to the formation of Tribogenics and the development of the rod and band x-ray architecture.

  10. Early victims of X-rays: a tribute and current perception

    PubMed Central

    Sansare, K; Khanna, V; Karjodkar, F

    2011-01-01

    X-rays were discovered in 1895 and since then much has been written about Wilhelm Roentgen and the events surrounding the discovery. However, there have been only scattered references in the literature about the early workers who dedicated their life, and death, to X-rays. Radiology has come of age since then. Large exposure times have been reduced to milliseconds and there has been a change from analogue to digital. The advent of new and rapidly developing modalities and the ubiquitous presence of cone beam CT (CBCT) highlight the need to remember the early victims of X-rays, especially with the lack of universal guidelines for taking a CBCT scan. The aim of this article is to alert the oral radiologist to exposing patients irrespective of need, and to pay respect to the victims on the 116th anniversary of the discovery of X-rays. PMID:21239576

  11. Geological cycles and a two-stage history of the Continental Crust (Robert Wilhelm Bunsen Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Hawkesworth, Chris J.; Cawood, Peter A.; Dhuime, Bruno

    2014-05-01

    The continental crust is the archive of Earth history, and the apparently cyclical nature of geological evolution is a feature of the geological record. The advent of radiometric ages has highlighted that the spatial and temporal distribution of the Earth's record of rock units and events is heterogeneous with distinctive peaks and troughs in the distribution of ages of igneous crystallization, metamorphism, continental margins and mineralization. It is argued that the temporal distribution largely reflects the different preservation potential of rocks generated in different tectonic settings, rather than fundamental pulses of activity, and the peaks of ages are linked to the timing of supercontinent assembly. In contrast there are other signals, such as the Sr isotope ratios of seawater, mantle temperatures, and redox conditions on the Earth, where the records are regarded as primary because they are not sensitive to the numbers of samples of different ages that have been analysed. Models based on the U-Pb, Hf and O isotope ratios of detrital zircons suggest that at least ~60-70% of the present volume of the continental crust had been generated by 3 Ga. The sedimentary record is biased by preferential sampling of relatively young material in their source terrains. The implication is that there were greater volumes of continental crust in the Archaean than might be inferred from the compositions of detrital zircons and sediments. The growth of continental crust was a continuous rather than an episodic process, but the rates of continental growth were significantly higher before 3 Ga than subsequently. The time-integrated Rb/Sr ratios, and the average SiO2 contents, indicate that new continental crust was largely mafic over the first 1.5 Ga of Earth's evolution, and that significant volumes of pre-3 Ga crust may have been associated with intraplate magmatism. Since ~3 Ga there has been an increase in Rb/Sr, SiO2, and the inferred thickness of new crust, consistent with an increase of continental input into the oceans and the onset of plate tectonics. The 60-70% of the present volume of the continental crust estimated to have been present at 3 Ga, contrasts markedly with the <10% of crust of that age apparently still preserved and it requires ongoing destruction (recycling) of early formed crust and subcontinental mantle lithosphere back into the mantle through processes such as subduction and delamination.

  12. [Ferdinand Albert Wilhelm von Brunn (1849-1895): Rostock's contribution to urology at the end of the 19th century].

    PubMed

    Dräger, D L; Protzel, C; Hakenberg, O W

    2015-05-01

    While the biographies of other prominent anatomists of the 19th century have been described in detail, little is known about Albert von Brunn. His most important scientific contributions were the description of the embryology and histology of the adrenal glands and of the Brunn epithelial nests of the urothelium which are considered pathognomonic for cystitis cystica. PMID:25875930

  13. [Considerations concerning the award of the first Nobel Prize in Physics to Wilhelm Conrad Röntgen].

    PubMed

    Luberti, R F; Bagur, D B; Ponticelli, R; Brezina, A J

    1998-11-01

    By the end of the 19th century, the quantity of scientists of great value was so big that selecting one for the top prize was not easy at all. Opinions were divided, giving rise to the personal controversy depicted in this article. PMID:11639041

  14. Travelogue of Konrad Keilhack (1858-1944), Geologist from Berlin, attending the International Geological Congress 1897 in St. Petersburg (Russia)

    NASA Astrophysics Data System (ADS)

    Pfaffl, Fritz A.; Dullo, Wolf-Christian

    2015-09-01

    Keilhack reported his impressions from his participation at the International Geological Congress in Russia in 1897 in several consecutive articles. In the more than 100 years since that time, a lot has changed. Apart from the totally different style of scientific presentations, with almost no illustrations, except maps, being shown during a talk, field trips were also a very special event, involving huge amounts of logistics. More than 200 people were transported to very remote areas of the European part of Russia. As well as organizing transportation by coaches and horses, places to stay overnight had to be found in large numbers and special regulations had to be issued by the government to allow access to various outcrops. Keilhacks visit of the oil-producing sites around Baku are of special interest, since they belonged obviously to the most productive ones on the globe at that time.

  15. Thorium induced hepatic hemangioendothelioma. Roentgen-angiographic findings in two additional cases with clinical "inform and consent" problems.

    PubMed

    Curry, J L; Johnson, W G; Feinberg, D H; Updegrove, J H

    1975-11-01

    1. Two additional cases of presumed, thorium-induced hemangioendothelioma of the liver are reported. 2. The angiographic pattern of large venous lakes conforms closely to the pathologic descriitions of this malignancy. 3. To our knowledge, angiography of the thorotrast (and vinyl chloride) liver, before the clinical evolution of malignancy, has not been recorded and may provide information of prognostic and therapeutic value. 4. Incidental identification of thorium deposits in the tissues of clinically healthy patients creates perplexing "inform and consent" problems. Presumably, these must be solved on an individual basis. 5. Because the use of thorotrast has been discontinued since the early 1950s, all physicians reviewing chest and abdominal roentgenograms should be aware of the characteristic appearance of human thorotrast deposits, especially in the liver, spleen and celiac lymph nodes. 6. The number of living thorotrast "carriers" and previous deaths from thorotrast related malignancy seems highly uncertain at this time. PMID:1202981

  16. Development of Mirror Modules for the ART-XC Instrument aboard the Spectrum-Roentgen-Gamma Mission

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; O'Dell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Atkins, C.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2013-01-01

    MSFC is developing eight x-ray mirror modules for the ART-XC instrument on board the SRG Mission. The Engineering Unit tests are successful. MSFC is on schedule to deliver flight units in the November of 2013 and January 2014.

  17. [New developments in parameter-oriented roentgen densitometry perfusion analysis within the scope of heart catheter studies].

    PubMed

    Haude, M; Caspari, G; Baumgart, D; Spiller, P; Heusch, G; Erbel, R

    1997-04-01

    X-ray densitometric evaluation of digital subtraction coronary arteriograms allows a qualitative and quantitative detection of contrast medium propagation through the epicardial coronary arteries, the capillary system and the coronary venous system. So-called "time-density-curves" (TDCs) can be generated following Lambert-Beer's law similar to indicator dilution curves by using contrast medium as the indicator. Several time and density parameters can be derived from these TDCs, which are related to local myocardial perfusion. Different animal validation studies have shown the applicability of this concept for in-vivo evaluation of coronary blood flow and myocardial perfusion. Nevertheless, absolute measurement of volumetric coronary blood flow or myocardial perfusion failed. Therefore, relative changes in coronary blood flow or myocardial perfusion in response to pharmacologically induced maximum hyperemia were measured and coronary or myocardial perfusion reserve was calculated as the ratio of hyperemic flow or perfusion divided by baseline values. Despite theoretical attractions for an application during routine cardiac catheterization, this densitometric approach did not get a wide acceptance. Primary reason for this limited use in specialized centers was the time consuming process of densitometric evaluation of the subtraction coronary arteriograms, which require digital cine angiography and necessitates enormous computer hard ware. This main limitation has been overcome since more powerful computer hard ware (processor speed, hard disk space, digitization boards) has become rapidly available during the last years at more moderate pricing and digital techniques today are state of the art in cardiac catheterization laboratories. In addition, soft ware program packages allowed an automatization of the digitization and densitometric evaluation process. These programs include ECG triggered cine image digitization with improved temporal resolution, semiautomatic definition of regions-of-interest including definition of reference regions-of-interest for the detection of background density changes and quality-controlled densitometric parameter analysis. This progress made an application during routine cardiac catheterization feasible. In animal validation studies this improved X-ray densitometric approach for evaluation of local myocardial perfusion was validated versus colour-coded microsphere techniques. The time parameter "rise time", defined as the time from the start of local contrast medium induced density change to its maximum revealed a close correlation (r2 = 0.965) to the results of the microsphere technique over a wide range of perfusion. We have applied this technique before and after coronary interventions such as balloon angioplasty and stenting. Results documented an improvement of poststenotic myocardial perfusion reserve immediately after coronary balloon angioplasty and an additional improvement after adjunct coronary stenting. Only after stenting but usually not after coronary balloon angioplasty alone poststenotic myocardial perfusion reserve gained the intraindividual reference level, measured in a perfusion bed supplied by an epicardial coronary artery without stenoses. These results documented the functional benefit of coronary stenting on poststenotic myocardial perfusion in addition to the well known morphologic benefit with the creation of a larger and more circular conduit. PMID:9206707

  18. The thermal control system of the x-ray telescope eROSITA on Spektrum-Roentgen-Gamma

    NASA Astrophysics Data System (ADS)

    Fürmetz, Maria; Eder, Josef; Pfeffermann, Elmar; Predehl, Peter; Tiedemann, Lars

    2012-09-01

    The X-ray telescope eROSITA is the main instrument besides the Russian ART-XC on the Spektrum-Rontgen-Gamma mission. Starting from 2014, an all-sky survey will be performed in the range between 0.3-10keV, followed by pointed observations. The main objective of thismission is the detection of 100 0000 galaxy clusters in order to constrain cosmological parameters, amongst others the density distribution and evolution of dark energy. Due to the minimum lifetime of seven years the thermal control system has to be completely passive without any consumables. With the ideal operational temperature of the CCD cameras being between 173K and 183K, this requires a very effective heat rejection system, consisting of a complex heat pipe system and a good thermal insulation. Simultaneously, a very sensitive temperature control via variable conductance heat pipes is implemented. For special outgassing requirements at the betinning of the mission these heat pipes are not working after launch but can be switched on any time. On the other hand the mirror moduules have to be tempered at room temperature and more than 200W of the electronics have to be dissipated without affecting the surrounding components or the satellite structure. The thermal control system has to be able to keep up the required temperature range and has to guarantee the optimum working conditions for all parts of the instrument. Calculations and verification tests validated the thermal concept.

  19. Markerless Roentgen Stereophotogrammetric Analysis for in vivo implant migration measurement using three dimensional surface models to represent bone.

    PubMed

    Seehaus, Frank; Olender, Gavin D; Kaptein, Bart L; Ostermeier, Sven; Hurschler, Christof

    2012-05-11

    Recent studies have shown that model-based RSA using implant surface models to detect in vivo migration is as accurate as the classical marker-based RSA method. Use of bone surface models would be a further advancement of the model-based method by decreasing complications arising from marker insertion. The aim of this pilot investigation was to assess the feasibility of a "completely markerless" model-based RSA in detecting migration of an implant using bone surface models instead of bone markers. A total knee arthroplasty (TKA) was performed on a human cadaver knee, which was subsequently investigated by repeated RSA measurements performed by one observer. The cadaver knee was CT scanned prior to implantation of the TKA. Tibia-fibular surface models were created using two different commercially available software packages to investigate the effect of segmentation software on the accuracy of repeated migration measures of zero displacement by one observer. Reverse engineered surface models of the TKA tibial component were created. The analysis of the RSA images was repeated 10 times by one individual observer. For the markerless method, the greatest apparent migration observed about the three anatomical axes investigated was between -2.08 and 1.35 mm (SD ≤ 0.88) for z-axis translation, and -4.57° to 7.86° (SD ≤ 3.17) for R(y)-axis rotation, which were well beyond out of the range of what is typically considered adequate for clinically relevant RSA measurements. Use of tibia-fibular surface models of the bone instead of markers could provide practical advantages in evaluating implant migration. However, we found the accuracy and precision of the markerless approach to be lower than that of marker-based RSA, to a degree which precludes the use of this method for measuring implant migration in its present form. PMID:22465625

  20. German-American Cultural Interaction in the Jacksonian Era: Six Unpublished Letters by Francis Lieber and John Pickering to Wilhelm von Humboldt.

    ERIC Educational Resources Information Center

    Mueller-Vollmer, Kurt

    1998-01-01

    Letters by German-American writer and political scientist Francis Lieber and American lawyer and linguist John Pickering to Wilhem von Humboldt in Berlin, published here for the first time, give insight into the cultural interaction between Germany and the United States during the Jacksonian era, and may open new perspectives for German-American…

  1. How Wilhelm Dilthey Influenced Popular Science Writing: Kurd Laßwitz's "Homchen. Ein Tiermärchen aus der oberen Kreide"

    NASA Astrophysics Data System (ADS)

    Azzouni, Safia

    In the second half of the nineteenth century, popularization of science appeared to be a necessity of the time. Scientists and politicians discussed the pros and cons of making scientific knowledge accessible to the public. The question of how and by whom popularization should be done was a common topic in newspapers and magazines of the time. Even though museums as well as zoological and botanical gardens played an important role in disseminating knowledge, it can be said that the popularization of science basically was (and probably still is) a "language-based event".1

  2. A Brazilian in the Reich of Wilhelm II: Henrique da Rocha Lima, Brazil-Germany relations and the Instituto Oswaldo Cruz, 1901-1909.

    PubMed

    Silva, André Felipe Cândido da

    2013-03-01

    This article follows the career of the Brazilian physician Henrique da Rocha Lima, one of the first to join the group of young researchers working at the Instituto Soroterápico de Manguinhos (Instituto Oswaldo Cruz). It describes his first voyage to Germany where he specialized in microbiology and pathological anatomy, training that shaped his subsequent professional identity. The tensions and dilemmas experienced by Rocha Lima provide an insight into what it meant to dedicate oneself to a scientific career in Brazil at the start of the twentieth century. They also reveal the importance of the relations with the German-speaking world for the experimental medicine that became established under the leadership of Oswaldo Cruz. PMID:23559048

  3. The State of the Art of Medical Imaging Technology: from Creation to Archive and Back

    PubMed Central

    Gao, Xiaohong W; Qian, Yu; Hui, Rui

    2011-01-01

    Medical imaging has learnt itself well into modern medicine and revolutionized medical industry in the last 30 years. Stemming from the discovery of X-ray by Nobel laureate Wilhelm Roentgen, radiology was born, leading to the creation of large quantities of digital images as opposed to film-based medium. While this rich supply of images provides immeasurable information that would otherwise not be possible to obtain, medical images pose great challenges in archiving them safe from corrupted, lost and misuse, retrievable from databases of huge sizes with varying forms of metadata, and reusable when new tools for data mining and new media for data storing become available. This paper provides a summative account on the creation of medical imaging tomography, the development of image archiving systems and the innovation from the existing acquired image data pools. The focus of this paper is on content-based image retrieval (CBIR), in particular, for 3D images, which is exemplified by our developed online e-learning system, MIRAGE, home to a repository of medical images with variety of domains and different dimensions. In terms of novelties, the facilities of CBIR for 3D images coupled with image annotation in a fully automatic fashion have been developed and implemented in the system, resonating with future versatile, flexible and sustainable medical image databases that can reap new innovations. PMID:21915232

  4. Fritz Reiche and German Refugee Scientists

    NASA Astrophysics Data System (ADS)

    Bederson, Benjamin

    2003-04-01

    Fritz Reiche (1883-1969) was a distinguished theoretical physicist, a student and colleague of Wilhelm Roentgen, Max Planck, Fritz Haber, Rudolf Ladenburg, James Franck, Max Born, Max von Laue and other early luminaries. He was coauthor of the famous Thomas-Reiche-Kuhn sum rule, and author of the seminal book The Quantum Theory, first published in 1920. He was one of the last Jewish physicists to leave Germany during the Nazi period, in 1941. In his book "Heisenberg's War" Thomas Powers relates that Reiche bore news of German work on nuclear fission, in a message from Friedrich Houtermans to Wigner and others in Princeton, where Reiche lived in Einstein's home during the summer of 1941. Reiche's son Hans later claimed that this incident played a significant role in convincing Einstein to write that letter to President Roosevelt. In this talk I will relate the difficulties Reiche experienced, first in leaving Germany and then in reestablishing his physics career in the US. He finally obtained an adjunct position at NYU where he served until his retirement. The role played by the renowned Emergency Committee in Aid of Displaced Foreign Scholars will be discussed. The particular role played by Ladenburg, who was instrumental in obtaining a small grant for Reiche permitting him to obtain a US visa, in helping many physicists leave Nazi Germany and occupied countries, will also be described.

  5. Evolution of Medical Imaging and Computational Demands

    NASA Astrophysics Data System (ADS)

    Deans, Stanley R.

    2000-11-01

    The first medical images produced using x-rays appeared less than a year after the discovery of x-rays by Wilhelm Roentgen in 1895. For over a century x-ray projection radiography has been and continues to be the most widely used diagnostic imaging modality. For over seventy years mathematics and computational methods were used in a general way for image processing and analysis. The really challenging mathematical and computational problems did not emerge until the 1970s with the beginning of computed tomography (CT) to produce images popularly known as CAT (computer-assisted tomography) scans. This was followed rapidly by positron-emission tomography (PET) and single photon emission computed tomography (SPECT). Magnetic resonance imaging (MRI) emerged in the 1980s and is in many ways the most informative medical imaging methodology. Computer-based mathematical methods are fundamental to the success of these imaging modalities, and are increasingly important in several other novel imaging techniques. The technologies involved in each modality are competely different, have varying diagnostic value, and are described by different fundamental equations. The common underlying theme is that of the reconstruction of important characteristics of medical interest from indirect measurements. Several of these methodologies for visualizing internal body anatomy and function will be discussed and related to the evolution of computational capabilities. This brings out aspects of these biomedical imaging technologies where a deeper understanding is needed, and to frontiers where future advances are likely to come from continued research in physics jointly with the mathematical sciences.

  6. The state of the art of medical imaging technology: from creation to archive and back.

    PubMed

    Gao, Xiaohong W; Qian, Yu; Hui, Rui

    2011-01-01

    Medical imaging has learnt itself well into modern medicine and revolutionized medical industry in the last 30 years. Stemming from the discovery of X-ray by Nobel laureate Wilhelm Roentgen, radiology was born, leading to the creation of large quantities of digital images as opposed to film-based medium. While this rich supply of images provides immeasurable information that would otherwise not be possible to obtain, medical images pose great challenges in archiving them safe from corrupted, lost and misuse, retrievable from databases of huge sizes with varying forms of metadata, and reusable when new tools for data mining and new media for data storing become available. This paper provides a summative account on the creation of medical imaging tomography, the development of image archiving systems and the innovation from the existing acquired image data pools. The focus of this paper is on content-based image retrieval (CBIR), in particular, for 3D images, which is exemplified by our developed online e-learning system, MIRAGE, home to a repository of medical images with variety of domains and different dimensions. In terms of novelties, the facilities of CBIR for 3D images coupled with image annotation in a fully automatic fashion have been developed and implemented in the system, resonating with future versatile, flexible and sustainable medical image databases that can reap new innovations. PMID:21915232

  7. [Video-roentgen cinematographic evaluation of pharyngeal phase disorders during swallowing in patients after partial laryngectomy due to localized supraglottic cancer].

    PubMed

    Strek, P; Urbanik, A; Rero?, E; Modrzejewski, M; Sk?adzie?, J; Belowska, J; Kitli?ski, Z; Groty?ska, M; Chrzan, R

    2001-01-01

    Videorentgenocinematographic examinations of swallowing were conducted on 81 patients after partial laryngectomy and on 35 subjects being a control group. Resection of piriform recess, a part of base of the tongue, the hyoid bone or its part is the factor that causes intensified difficulty during swallowing and increase in the frequency of the occurrence of aspiration. The results of videorentgenocinematographic examinations indicate that the shape and mobility of the tongue and the mobility of remaining after the surgery parts of the larynx have the greatest influence on the efficient swallowing in patients who have undergone partial laryngectomy due to cancer initially located in the supraglottic area. The larynx mobility is closely related to the remaining of the hyoid bone. The importance of remaining the possibly non-deformed structure and mobility of the tongue during partial laryngectomy involves the issue of reconstruction of defects occurred during the surgery. Videorentgenocinematographic examinations confirm the effectiveness of the method involving reconstruction of defects in a part of the base of the tongue with a vascular pedicle flap of the submandibular gland. PMID:11355477

  8. Overview of the Chandra X-Ray Observatory Facility

    NASA Technical Reports Server (NTRS)

    Weisskopf, M. C.; Six, N. Frank (Technical Monitor)

    2002-01-01

    The Chandra X-Ray Observatory (originally called the Advanced X-Ray Astrophysics Facility - AXAF) is the X-Ray component of NASA's "Great Observatory" Program. Chandra is a NASA facility that provides scientific data to the international astronomical community in response to scientific proposals for its use. The Observatory is the product of the efforts of many organizations in the United States and Europe. The Great Observatories also include the Hubble Space Telescope for space-based observations of astronomical objects primarily in the visible portion of the electromagnetic spectrum, the now defunct Compton Gamma- Ray Observatory that was designed to observe gamma-ray emission from astronomical objects, and the soon-to-be-launched Space Infrared Telescope Facility (SIRTF). The Chandra X-Ray Observatory (hereafter CXO) is sensitive to X-rays in the energy range from below 0.1 to above 10.0 keV corresponding to wavelengths from 12 to 0.12 nanometers. The relationship among the various parts of the electromagnetic spectrum, sorted by characteristic temperature and the corresponding wavelength, is illustrated. The German physicist Wilhelm Roentgen discovered what he thought was a new form of radiation in 1895. He called it X-radiation to summarize its properties. The radiation had the ability to pass through many materials that easily absorb visible light and to free electrons from atoms. We now know that X-rays are nothing more than light (electromagnetic radiation) but at high energies. Light has been given many names: radio waves, microwaves, infrared, visible, ultraviolet, X-ray and gamma radiation are all different forms. Radio waves are composed of low energy particles of light (photons). Optical photons - the only photons perceived by the human eye - are a million times more energetic than the typical radio photon, whereas the energies of X-ray photons range from hundreds to thousands of times higher than that of optical photons. Very low temperature systems (hundreds of degrees below zero Celsius) produce low energy radio and microwave photons, whereas cool bodies like our own (about 30 degrees Celsius) produce infrared radiation. Very high temperatures (millions of degrees Celsius) are one way of producing X-rays.

  9. 77 FR 51606 - Culturally Significant Objects Imported for Exhibition Determinations: Extravagant Inventions...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ... Furniture of the Roentgens,'' Formerly Titled ``Seductive Luxury and Innovation: The Furniture of Abraham... State pertaining to the exhibition ``Seductive Luxury and Innovation: The Furniture of Abraham and David... Inventions: The Princely Furniture of the Roentgens'' and to include additional objects as part of...

  10. The Question of Teaching Vocabulary: Which Words? In What Ways?

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D., Ed.

    2013-01-01

    Recognizing the importance of vocabulary for comprehension, Wilhelm asks two key questions: "which words do I teach and how should I teach them?" Through years of trial and error, Wilhelm has adopted these principles to answer "which words": teach "important" words students will see and use again; words necessary to conceptual understanding; words…

  11. Considering Hermeneutics and Education: Hermes, Teachers, and Intellectualism.

    ERIC Educational Resources Information Center

    Boyles, Deron Robert

    Teacher roles in contemporary American schools should be more closely aligned to hermeneutics as the study of meaning (interpretation/understanding). A marriage between Platonic notions of interpretation and the quest for meaning with the interpretive theories of Friedrich Schleiermacher, Wilhelm von Humboldt, Wilhelm Dilthey, and Hans-Georg…

  12. Delta II

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Delta II expendable launch vehicle with the ROSAT (Roentgen Satellite), cooperative space X-ray astronomy mission between NASA, Germany and United Kingdom, was launched from the Cape Canaveral Air Force Station on June 1, 1990.

  13. Calibration of the ART-XC/SRG X-ray Mirror Modules

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; Zavlin, V.; Swartz, D.; Kolodziejczak, J.; Elsner, R.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2014-01-01

    Seven x-ray mirror modules are being fabricated at the Marshall Space Flight Center (MSFC) for the Astronomical Roentgen Telescope (ART) instrument to be launched on board of the Spektrum Roentgen Gamma (SRG) Mission. As they are completed, the modules are tested and calibrated at the MSFC's 104-m Stray Flight Facility. The results of these calibration measurements and comparisons with theoretical models will be presented.

  14. In the footsteps of astronomers in Bremen and Lilienthal. (German Title: Auf den Spuren von Astronomen in Bremen und Lilienthal)

    NASA Astrophysics Data System (ADS)

    Langkavel, Arno

    When Bremen and Lilienthal are mentioned, people interested in the history of astronomy will first of all remember Wilhelm Olbers (1785-1840) and Johann Hieronymus Schroeter (1745-1816). In addition to them, Friedrich Wilhelm Bessel (1784-1846) and Carl Friedrich Gauß (1777-1855) have also left their traces. Two walks describe the main memorial sites, which are all outdoors and easily accessible to the general public.

  15. Physicists and Physics in Munich

    NASA Astrophysics Data System (ADS)

    Teichmann, Jürgen; Eckert, Michael; Wolff, Stefan

    We give a tour of Munich and some outlying sites that focuses on the lives and work of the most prominent physicists who lived in the city, Count Rumford, Joseph Fraunhofer, Georg Simon Ohm, Max Planck, Ludwig Boltzmann, Albert Einstein, Wilhelm Conrad Röntgen, Wilhelm Wien, Arnold Sommerfeld, Max von Laue, and Werner Heisenberg. We close with a self-guided tour that describes how to reach these sites in Munich.

  16. Nature, Human Nature, and Solutions to Problems.

    ERIC Educational Resources Information Center

    Pedrini, D. T.; Pedrini, B. C.

    This paper promotes an undergraduate course that would discuss the great ideas of Plato, St. Paul, Karl Marx, Sigmund Freud, Jean Paul Sartre, B. F. Skinner, and Konrad Lorenz. This course would help students understand human values and behaviors while focusing on historical, world, and national problems. Tentative solutions would then be…

  17. Some Issues Concerning Aggression and Violence in Human Beings.

    ERIC Educational Resources Information Center

    Ponton, Elizabeth

    1986-01-01

    Examines aggression and violence from an interdisciplinary perspective. Humanistic psychologist Rollo May sees violence as the end product of power deprivation. Anthropologists Konrad Lorenz and Robert Ardrey regard aggression as an innate biological drive. Anthropologist Richard Leakey views it as a learned, culturally determined response.…

  18. Caveat Lector: Reviewing Popular Social Science.

    ERIC Educational Resources Information Center

    Hixson, Vivian Scott

    1981-01-01

    Discusses problems with reviews and criticisms of popular social science books: the quality and background of reviewers, the difficulty of distinguishing between fact and opinion, and the scarcity of competent reviewers. Analyzes reviews of Robert Ardrey's "African Genesis" and "The Territorial Imperative," Konrad Lorenz's "On Aggression," and…

  19. Nature, Human Nature, and Solutions to Problems.

    ERIC Educational Resources Information Center

    Pedrini, D. T.; Pedrini, B. C.

    This paper promotes an undergraduate course that would discuss the great ideas of Plato, St. Paul, Karl Marx, Sigmund Freud, Jean Paul Sartre, B. F. Skinner, and Konrad Lorenz. This course would help students understand human values and behaviors while focusing on historical, world, and national problems. Tentative solutions would then be

  20. Some reflections on the influence of Chinese thought on Jung and his psychological theory.

    PubMed

    Stein, Murray

    2005-04-01

    Jung claimed that Richard Wilhelm, whose masterful translations of Chinese wisdom literature into a European language (German) and thence into Western consciousness have brought Chinese modes of thinking to so many, was one of the most important influences on his own life and work. The contacts between the two men, which took place from the early 1920's until Wilhelm's death in 1930, were few but intense and for Jung decisive in several ways. Wilhelm's translations of the I Ching and The Secret of the Golden Flower opened new avenues for Jung that had far-reaching consequences on his research and writing after 1930. The latter opened the door to the study of alchemy as a key to the archetypal process of individuation as rooted in the collective unconscious. 'Synchronicity' is a term that grew out of his contact with Chinese thought, in particular with the I Ching. From his contact with Chinese thought, additionally, he received confirmation of the view, independently arrived at, that adult psychological development is not linear but rather circular and spiral-like. The letters between Jung and Wilhelm illuminate the great importance Jung ascribed to Wilhelm's contribution toward bridging East and West and the potential value of Chinese philosophy for psychotherapy. PMID:15817043

  1. Osteolysis of the clavicle

    SciTech Connect

    Ahmad, A.

    1988-12-02

    A letter to the editor and reply from the author are presented dealing with a radiology case-of-the-month. The superficial location of the clavicle makes it more prone to radiation effects only if low-energy roentgen rays or an electron beam is used. Since the case history does not describe the equipment used. The letter writer was not certain if the superficial location of the clavicle was a factor. If high-energy roentgen rays are used, the superficial location of the clavicle was a factor. If high-energy roentgen rays are used, the superficial location of the clavicle is advantageous since it will absorb a lesser dose compared with the deeper tissues.

  2. ART-XC/SRG: status of the x-ray optics development

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Ramsey, B.; Elsner, R.; O'Dell, S.; Kolodziejczak, J.; McCracken, J.; Zavlin, V.; Swartz, D.; Kilaru, K.; Atkins, C.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2014-07-01

    The Astronomical Roentgen Telescope (ART) instrument is a hard-x-ray instrument with energy response up to 30 keV that is to be launched on board of the Spectrum Roentgen Gamma (SRG) Mission. The instrument consists of seven identical mirror modules coupled with seven CdTe strip focal-plane detectors. The mirror modules are being developed at the Marshall Space Flight Center (MSFC.) Each module has ~65 sq. cm effective area and an on-axis angular resolution of 30 arcseconds half power diameter (HPD) at 8 keV. The current status of the mirror module development and testing will be presented.

  3. Flight programs and X-ray optics development at MSFC

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Ramsey, B.; O'Dell, S.; Elsner, R.; Kilaru, K.; Atkins, C.; Swartz, D.; Gaskin, J.; Weisskopf, M.

    The X-ray astronomy group at the Marshall Space Flight Center (MSFC) is developing electroformed nickel/cobalt x-ray optics for suborbital and orbital experiments. Suborbital instruments include the Focusing X-ray Solar Imager (FOXSI) and Micro-X sounding rocket experiments and the HEROES balloon payload. Our current orbital program is the fabrication of mirror modules for the Astronomical Roentgen Telescope (ART) to be launched on board the Russian-German Spectrum Roentgen Gamma Mission (SRG). A second component of our work is the development of fabrication techniques and optical metrology to improve the angular resolution of thin-shell optics to the arcsecond-level.

  4. Roentgenstructural analysis of Cristalline Cobalt II with 1,10- fenatrolin and tiosemicarbazid acetic acid.

    NASA Astrophysics Data System (ADS)

    Kon, Aviv Yu.

    The author has reported his long years research in the area of structure and Roentgen analysis of Cristalls. The talk concerns Roentgen analysis, Its first steps in Kishinev during the finish of 40-th and the beginning of 50-th. Some concerns was given to prof. T.I. Malinovskij,a graduated from the Yassy University one of the first Assistants Proff. at the Kishinev State Pedagogical Institute and later a leading scientist in the area of cristalls research in the Soviet Moldavia. Particularly, the actual talk was dedicated to interaction of acids with cristals of 1,10 fenatrolin.

  5. ART-XC/SRG: Status of the X-ray Optics Development

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; Elsner, R.; O'Dell, S.; Kolodziejczak, J.; McCracken, J.; Zavlin, V.; Swartz, D.; Kilaru, K.; Atkins, C.; Pavlinskiy, M.; Tkachenko, A.; Lapshov, I.

    2014-01-01

    The Astronomical Roentgen Telescope (ART) instrument is a hard-x-ray instrument with energy response up to 30 keV that is to be launched on board of the Spectrum Roentgen Gamma (SRG) Mission. The instrument consists of seven identical mirror modules coupled with seven CdTe strip focal-plane detectors. The mirror modules are being developed at the Marshall Space Flight Center (MSFC.) Each module has approx. 65 sq. cm effective area and an on-axis angular resolution of 30 arcseconds half power diameter (HPD) at 8 keV. The current status of the mirror module development and testing will be presented.

  6. Development and Calibration of the ART-XC Mirror Modules for the Spectrum Rontgen Gamma Mission

    NASA Technical Reports Server (NTRS)

    Ramsey, B.; Gubarev, M.; Elsner, R.; Kolodziejczak, J.; Odell, S.; Swartz, D.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2013-01-01

    The Spectrum-Röntgen-Gamma (SRG) mission is a Russian-lead X-ray astrophysical observatory that carries two co-aligned X-ray telescope systems. The primary instrument is the German-led extended ROentgen Survey with an Imaging Telescope Array (eROSITA), a 7-module X-ray telescope system that covers the energy range from 0.2-12 keV. The complementary instrument is the Astronomical Roentgen Telescope -- X-ray Concentrator (ART-XC or ART), a 7-module Xray telescope system that provides higher energy coverage, up to 30 keV.

  7. ART-XC/SRG: Status of the X-ray Optics Development

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; Zavlin, V.; Swartz, D.; Elsner, R. F.; ODell, S.; Kilaru, K.; Atkins, C.; McCracken, J.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2014-01-01

    The Astronomical Roentgen Telescope (ART) instrument is a hard x-ray instrument with energy response up to 30 keV that is to be launched on board of the Spectrum Roentgen Gamma (SRG) Mission. The instrument consists of seven identical mirror modules coupled with seven CdTe strip focal-plane detectors. The mirror modules are being developed at the Marshall Space Flight Center (MSFC.) Each module has approximately 65 sq. cm effective area and an on-axis angular resolution of 30 arcseconds half power diameter (HPD) at 8 keV. The current status of the mirror module development and testing will be presented.

  8. ART-XC/SRG: Status of the X-ray Optics Development

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; Elsner, R.; O'Dell, S.; Kolodziejczak, J.; McCracken, J.; Zavlin, V.; Swartz, D.; Kilaru, K.; Atkins, C.; Pavlinskiy, M.; Tkachenko, A.; Lapshov, I.

    2014-01-01

    The Astronomical Roentgen Telescope (ART) instrument is a hard-x-ray instrument with energy response up to 30 keV that is to be launched on board of the Spectrum Roentgen Gamma (SRG) Mission. The instrument consists of seven identical mirror modules coupled with seven CdTe strip focal-plane detectors. The mirror modules are being developed at the Marshall Space Flight Center (MSFC.) Each module has approximately 65 sq. cm effective area and an on-axis angular resolution of 30 arcseconds half power diameter (HPD) at 8 keV. The current status of the mirror module development and testing will be presented.

  9. Rosenman's "Serendipity and Scientific Discovery" Revisited: Toward Defining Types of Chance Events.

    ERIC Educational Resources Information Center

    Diaz de Chumaceiro, Cora L.; Yaber O., Guillermo E.

    1994-01-01

    The role of serendipity or "chance in all its forms" in scientific discovery is considered. The need to differentiate between purely accidental events and Rothenberg's "articulations of error" when discussing scientific discoveries is stressed. Examples of articulations of errors are noted, including Fleming (penicillin), Roentgen (X-ray effect),…

  10. [Causes of removal of kidney allotransplants].

    PubMed

    Rozental', R L; Il'inskiĭ, I M; Tikhomirova, T E; Bitsans, Ia B; Luse, L Ia

    1983-07-01

    The most frequent causes of cessation of the functioning of 60 kidney transplants was an acute rejection reaction and thrombosis of main vessels of the transplanted kidney. The authors believe the attraction of the cytological analysis of the urine, instrumental and roentgen-radiological examinations as well as biochemical data to improve the diagnosis of pathological changes in the transplant. PMID:6353738

  11. Atomic Pioneers, Book 2, From the Mid-19th to the Early 20th Century. A World of the Atom Series Booklet.

    ERIC Educational Resources Information Center

    Hiebert, Ray; Hiebert, Roselyn

    This booklet is concerned with the last half of the 19th and the beginning of the 20th century when a great surge of knowledge vital to atomic science took place, as illustrated by work by Faraday, Mendeleev, Roentgen, Becquerel and the Curies. Each succeeding discovery brought atomic science closer to the great breakthrough that marked the close…

  12. Tinea corporis overlying the thyroid gland after radioiodine (131I) treatment of Graves' disease

    SciTech Connect

    Moreno, A.J.; Hartshorne, M.F.; Yedinak, M.A.; Crooks, L.A.; Fox, B.J.

    1986-04-01

    A case of tinea corporis involving the skin overlying the thyroid gland is described in a 36-year-old man who had received radioiodine treatment for Graves' disease. The dermatophytosis mimicked a delayed roentgen erythema. Radiation to the dermis may have locally altered the cell-mediated immunity and predisposed this patient to the dermatophytosis.

  13. Study of a Solar X-Ray Telescope

    NASA Astrophysics Data System (ADS)

    Golub, Leon

    1997-05-01

    The highly structured nature of the outer solar atmosphere seems to be intimately linked to the presence, at the solar surface, of magnetic fields that have been generated inside the Sun and have emerged to the surface. The corona is brightest (and also hottest) at just those locations where the magnetic field has emerged from inside the Sun. Dynamo theory predicts that strong magnetic fields will be generated deep in the solar interior and that bundles or 'ropes' of magnetic flux will float to the surface. When this happens, a magnetically bipolar region will become visible, extending above the surface in a three-dimensional structure. The field lines penetrate through the surface, showing two magnetic poles, and also exhibit a three-dimensional structure above the surface. The structure created by the field emergence is rooted in the (relatively) cool photosphere and extends through the chromosphere and transition region to the corona. Thus, the magnetic field creates a region, called an active region, which contains portions at temperatures from less than 104 K to greater than 106 K, and is therefore visible at wavelengths from the infrared through x-rays. The locations where the magnetic field leaves and reenters the visible surface are called the 'footpoints' of the coronal structures associated with the magnetic field. The magnetic fields themselves are not directly visible. However, the hot coronal plasma is, for the most part, constrained to follow the direction of the magnetic field lines in the atmosphere. Now, 100 years after the discovery of x-rays by Wilhelm Roentgen in 1896, we can routinely make observations of the solar corona from outside the Earth's atmosphere in this region of the electromagnetic spectrum. As shown by comparing x-ray images with magnetograms, the bright corona over these bipolar magnetic regions consists of closed structures that seem to follow the orientation of the magnetic field. Although we can see down to the photosphere at x-ray wavelengths when observing the disk of the Sun, this part of the solar atmosphere emits so little that far from the peak of its Planck curve it appears dark in x-ray images. This impression of hot plasma following the magnetic field direction is further strengthened by quantitative studies that calculate coronal magnetic field strength and direction based on photospheric measurements and compare them with the observed brightness and location of the x-ray emitting structures. Such comparisons make it clear that, for the most part, the hot plasma conforms to the geometry of the magnetic field and that the coronal brightness is strongly linked to the strength of the magnetic fields which have erupted to the solar surface from the interior. It is also the case that the larger-scale, fainter corona, as well as coronal holes, are strongly influenced by the large-scale solar magnetic field. We may get a small hint of the reason that the coronal plasma outlines the direction of B by examining the thermal conductivity of a hot plasma in the presence of a magnetic field. This quantity has enormously different values in the directions parallel and perpendicular to the field for a coronal temperature of 106 K, a particle density of 109/cu cm and a magnetic field strength of 100 G, the conductivity along the field is approximately 13 orders of magnitude greater than that perpendicular to the field. It is therefore not surprising that a parcel of plasma which is locally heated would conduct that heat preferentially in the direction of the field. We also note that the thermal conductivity parallel to the magnetic field increases with temperature T, while the perpendicular conductivity decreases. To the extent that the loop aspect ratio, i.e., the ratio of loop length to loop width, is determined by the thermal conductivity, we would expect that higher temperature loops are longer and thinner than cooler ones. However, if the loop width becomes smaller than the spatial resolution of the observing instrument, this effect will not be directly observable. For organizational purposes, we provide a listing of some scientific objectives for a Solar-B x-ray telescope, arranged in terms of identifiable features in the corona.

  14. Study of a Solar X-Ray Telescope

    NASA Technical Reports Server (NTRS)

    Golub, Leon

    1997-01-01

    The highly structured nature of the outer solar atmosphere seems to be intimately linked to the presence, at the solar surface, of magnetic fields that have been generated inside the Sun and have emerged to the surface. The corona is brightest (and also hottest) at just those locations where the magnetic field has emerged from inside the Sun. Dynamo theory predicts that strong magnetic fields will be generated deep in the solar interior and that bundles or 'ropes' of magnetic flux will float to the surface. When this happens, a magnetically bipolar region will become visible, extending above the surface in a three-dimensional structure. The field lines penetrate through the surface, showing two magnetic poles, and also exhibit a three-dimensional structure above the surface. The structure created by the field emergence is rooted in the (relatively) cool photosphere and extends through the chromosphere and transition region to the corona. Thus, the magnetic field creates a region, called an active region, which contains portions at temperatures from less than 10(exp 4) K to greater than 10(exp 6) K, and is therefore visible at wavelengths from the infrared through x-rays. The locations where the magnetic field leaves and reenters the visible surface are called the 'footpoints' of the coronal structures associated with the magnetic field. The magnetic fields themselves are not directly visible. However, the hot coronal plasma is, for the most part, constrained to follow the direction of the magnetic field lines in the atmosphere. Now, 100 years after the discovery of x-rays by Wilhelm Roentgen in 1896, we can routinely make observations of the solar corona from outside the Earth's atmosphere in this region of the electromagnetic spectrum. As shown by comparing x-ray images with magnetograms, the bright corona over these bipolar magnetic regions consists of closed structures that seem to follow the orientation of the magnetic field. Although we can see down to the photosphere at x-ray wavelengths when observing the disk of the Sun, this part of the solar atmosphere emits so little that far from the peak of its Planck curve it appears dark in x-ray images. This impression of hot plasma following the magnetic field direction is further strengthened by quantitative studies that calculate coronal magnetic field strength and direction based on photospheric measurements and compare them with the observed brightness and location of the x-ray emitting structures. Such comparisons make it clear that, for the most part, the hot plasma conforms to the geometry of the magnetic field and that the coronal brightness is strongly linked to the strength of the magnetic fields which have erupted to the solar surface from the interior. It is also the case that the larger-scale, fainter corona, as well as coronal holes, are strongly influenced by the large-scale solar magnetic field. We may get a small hint of the reason that the coronal plasma outlines the direction of B by examining the thermal conductivity of a hot plasma in the presence of a magnetic field. This quantity has enormously different values in the directions parallel and perpendicular to the field for a coronal temperature of 10(exp 6) K, a particle density of 10(exp 9)/cu cm and a magnetic field strength of 100 G, the conductivity along the field is approximately 13 orders of magnitude greater than that perpendicular to the field. It is therefore not surprising that a parcel of plasma which is locally heated would conduct that heat preferentially in the direction of the field. We also note that the thermal conductivity parallel to the magnetic field increases with temperature T, while the perpendicular conductivity decreases. To the extent that the loop aspect ratio, i.e., the ratio of loop length to loop width, is determined by the thermal conductivity, we would expect that higher temperature loops are longer and thinner than cooler ones. However, if the loop width becomes smaller than the spatial resolution of the observing instrument, this effect will not be directly observable. For organizational purposes, we provide a listing of some scientific objectives for a Solar-B x-ray telescope, arranged in terms of identifiable features in the corona.

  15. 76 FR 37029 - Margin and Capital Requirements For Covered Swap Entities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... RAD (202) 874-3978, Kurt Wilhelm, Director, Financial Markets Group (202) 874-4479, Jamey Basham... variation margin requirements on all non-cleared swaps and non-cleared security-based swaps. In recognition... that the public comment period would close on June 24, 2011.\\3\\ \\1\\ See 76 FR 27564. \\2\\...

  16. Photothermal Therapy: Cancer Cell Internalization of Gold Nanostars Impacts Their Photothermal Efficiency In Vitro and In Vivo: Toward a Plasmonic Thermal Fingerprint in Tumoral Environment (Adv. Healthcare Mater. 9/2016).

    PubMed

    Espinosa, Ana; Silva, Amanda K A; Sánchez-Iglesias, Ana; Grzelczak, Marek; Péchoux, Christine; Desboeufs, Karine; Liz-Marzán, Luis M; Wilhelm, Claire

    2016-05-01

    Because the ultimate target for photothermal therapy is the cancer cell, heating performances must be evaluated intracellularly. On page 1040 C. Wilhelm and team provide the first in vitro and in vivo photothermal measurements in cancer cells with gold nanostars. They demonstrate that once nanostars are internalized within endosomes, heat generation can change significantly. PMID:27166618

  17. Literacy and Neuroplasticity: Transforming Our Perspectives and Ourselves

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D.

    2010-01-01

    Wilhelm applies two of his core beliefs--that anyone can learn the next appropriate concept or process if they are provided with a meaningful situation and proper assistance, and that literacy and the kinds of texts we call literature provide a unique and powerful way of knowing and of transforming the self--to a look at how recent research on the…

  18. The Doubling Moment: Resurrecting Edgar Allan Poe

    ERIC Educational Resources Information Center

    Minnick, J. Bradley; Mergil, Fernando

    2008-01-01

    This article expands upon Jeffrey Wilhelm's and Brian Edmiston's (1998) concept of a doubling of viewpoints by encouraging middle level students to use dramatization to take on multiple perspectives, to pose interpretive questions, and to enhance critical inquiry from inside and outside of texts. The doubling moment is both the activation of

  19. Proceedings of the Annual Conference of the Western Regional Home Management-Family Economics Educators (25th, Scottsdale, Arizona, November 6-8, 1985).

    ERIC Educational Resources Information Center

    Berry, Ruth E., Ed.

    These proceedings consist of 12 presentations, most of which are followed by responses or comments. The papers include: "Integrating Family Economics and Family Counseling" (Hogan; discussants Schnittgrund, Wilhelm); "A Test of the Deacon-Firebaugh Management Model" (Gage, Schmid); "Perceived Income Adequacy and Selected Financial Management

  20. Hard-luck Scheele

    NASA Astrophysics Data System (ADS)

    Gibb, Bruce C.

    2015-11-01

    Carl Wilhelm Scheele had a hand in the discovery of at least six elements and contributed to the early development of chemistry in numerous other ways. Bruce Gibb looks into Scheele's story and considers why he doesn't get the credit that he deserves.

  1. The Rhetoric in Mathematics: Newton, Leibniz, the Calculus, and the Rhetorical Force of the Infinitesimal

    ERIC Educational Resources Information Center

    Reyes, G. Mitchell

    2004-01-01

    This essay investigates the rhetoric surrounding the appearance of the concept of the infinitesimal in the seventeenth-century Calculus of Sir Isaac Newton and Gottfried Wilhelm Leibniz. Although historians often have positioned rhetoric as a supplemental discipline, this essay shows that rhetoric is the "material" out of which a new and powerful

  2. Creating "Third Spaces": Promoting Learning through Dialogue

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D.

    2010-01-01

    Wilhelm offers us a definition of "third spaces" as "more democratic and dialogic spaces than a classroom, as well as a metaphor for a space in which new, hybrid, and challenging discourses and real-world knowledge and applications are created." With helpful background and examples, he urges us to create such spaces for our students, adamant that

  3. The Great War and the Shaping of the Twentieth Century.

    ERIC Educational Resources Information Center

    Baggett, Blaine; And Others

    1996-01-01

    Traces the convoluted alliances and diplomatic blundering that resulted in World War I. Places a large degree of the blame on Kaiser Wilhelm II who almost singlehandedly dismantled or ruptured the alliances and treaties of imperial chancellor Otto von Bismarck. Includes photos, paintings, and diary entries. (MJP)

  4. Astronomical dilettante or misunderstood genius? On Johann Hieronymus Schroeter's image in the history of science. (German Title: Astronomischer Dilettant oder verkanntes Genie? Zum Bild Johann Hieronymus Schroeters in der Wissenschaftsgeschichte)

    NASA Astrophysics Data System (ADS)

    Oestmann, Günther

    The paper deals with contemporary assessments of Johann Hieronymus Schroeter's (1745-1816) astronomical works - especially by Wilhelm Olbers and Carl Friedrich Gauß - and also later judgements of the scientific importance and significance of his observations voiced by astronomers and historians.

  5. Profile Measurements During Cavitation

    NASA Technical Reports Server (NTRS)

    Walchner, O.

    1944-01-01

    One of the problems of modern cavitation research is the experimental determination of the wing loads on airfoils during cavitation. Such experiments were made on various airfoils with the support of the naval ministry at the Kaiser Wilhelm Institute for Flow Research at Goettingen.

  6. History of experimental psychology from an Estonian perspective.

    PubMed

    Allik, Jüri

    2007-11-01

    A short review of the development of experimental psychology from an Estonian perspective is presented. The first rector after the reopening of the University of Dorpat (Tartu) in 1802, Georg Friedrich Parrot (1767-1852) was interested in optical phenomena which he attempted to explain by introducing the concept of unconscious inferences, anticipating a similar theory proposed by Herman von Helmholtz 20 years later. One of the next rectors, Alfred Wilhelm Volkmann (1800-1878) was regarded by Edwin Boring as one of the founding fathers of the experimental psychology. Georg Wilhelm Struve (1793-1864) played an essential part in solving the problem of personal equations. Arthur Joachim von Oettingen (1836-1920) developed a theory of music harmony, which stimulated his student Wilhelm Friedrich Ostwald (1853-1932) to study colour harmony. Emil Kraepelin (1856-1926), the founder of modern psychiatry, is by far the most important experimental psychologist who has worked in Estonia. His successor Wladimir von Tchisch (1855-1922), another student of Wilhelm Wundt, continued Kraepelin's work in experimental psychology. The lives of Wolfgang Köhler (1887-1967), who was born in Reval (Tallinn), and Oswald Külpe (1862-1915), who graduated from the University of Dorpat, extended the link between the history of experimental psychology and Estonia. Karl Gustav Girgensohn (1875-1925), the founder of the Dorpat School of the psychology of religion, stretched the use of experimental methods to the study of religious experience. PMID:16639614

  7. The Doubling Moment: Resurrecting Edgar Allan Poe

    ERIC Educational Resources Information Center

    Minnick, J. Bradley; Mergil, Fernando

    2008-01-01

    This article expands upon Jeffrey Wilhelm's and Brian Edmiston's (1998) concept of a doubling of viewpoints by encouraging middle level students to use dramatization to take on multiple perspectives, to pose interpretive questions, and to enhance critical inquiry from inside and outside of texts. The doubling moment is both the activation of…

  8. Next Steps in the Journey: Learning to Listen to Student Voices: Teaching with Our Mouths Shut

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D.

    2011-01-01

    According to Wilhelm, a teacher's power lies in learning to work "with" students, starting with listening. He recommends setting up conditions and mechanisms that help you learn from your students what they are learning, what challenges they are facing, and how best to teach them. Through inquiry, the classroom can become a vital and engaging…

  9. Drifting from Slow to "D'oh!": Working Memory Capacity and Mind Wandering Predict Extreme Reaction Times and Executive Control Errors

    ERIC Educational Resources Information Center

    McVay, Jennifer C.; Kane, Michael J.

    2012-01-01

    A combined experimental, individual-differences, and thought-sampling study tested the predictions of executive attention (e.g., Engle & Kane, 2004) and coordinative binding (e.g., Oberauer, Suss, Wilhelm, & Sander, 2007) theories of working memory capacity (WMC). We assessed 288 subjects' WMC and their performance and mind-wandering rates during…

  10. Development and Self-Identity: Hegel's Concept of Education.

    ERIC Educational Resources Information Center

    Vincent, A. W.; George, Michael

    1982-01-01

    This essay draws together various ideas on education that appear in the works of Georg Wilhelm Friedrich Hegel and demonstrates how these ideas relate to Hegel's total philosophy. Education, by retracing the path of the mind's self-realization, raises the individual's subjective consciousness to recognition of the rationality underlying social…

  11. [A note on the technical debate between Reich/Fenichel and Theodor Reik (1932-1936)].

    PubMed

    Schröter, Michael

    2005-01-01

    Wilhelm Reich's technical emphasis on the "systematic analysis of defenses" was controversial even before 1933. His main opponent in this field was Reik who expressed his criticism several times from 1932 to 1935. For Reik, the analytical process was essentially open, dependent on surprise. Fenichel, Reich's ally, defended a "scientific" approach, as opposed to "intuition", but later adopted a mediatory position. PMID:17152763

  12. The Humboldt Legacy: Reflections on the Past, Present, and Future of the European University.

    ERIC Educational Resources Information Center

    Nybom, Thorsten

    2003-01-01

    Discusses the uses and distortions that have been made over the years to the ideas about the university that Wilhelm von Humboldt advocated. Points out, however, that there remains much of value in the ideas articulated by Humboldt and his brother Alexander. (SLD)

  13. Learning to Play the Literacy and Learning Games--A Question of Enculturation

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D., Ed.

    2007-01-01

    Understanding that learning must be relevant and purposeful to be effective and engaging, Wilhelm emphasizes the value of teaching students "how to participate in meaningful activity in ways that make them increasingly expert in creating culture and . . . cultural meanings." He offers bullet points that suggest starting with students' experiences,

  14. How Principals Cultivate Shared Leadership

    ERIC Educational Resources Information Center

    Wilhelm, Terry

    2013-01-01

    Do teacher leaders in your school mainly fill the traditional roles of department chair or grade-level representative? Or do they lead their peers in collaborative teams whose primary focus is improving student learning? Terry Wilhelm, director of the School Leadership Center for Riverside County Office of Education in California, says that…

  15. Alphabet Soup: ERP, CT, and ACT for OCD

    ERIC Educational Resources Information Center

    Tolin, David F.

    2009-01-01

    The present article comments on the case conference presented in this issue, namely, Himle and Franklin's (Himle & Franklin, 2009) exposure and response prevention (ERP); Chosak and colleagues' (Chosak, Marques, Fama, Renaud, & Wilhelm, 2009) cognitive therapy (CT); and (Twohig, 2009) Acceptance and Commitment Therapy (ACT). Two questions are

  16. The International Relations of the Struves

    NASA Astrophysics Data System (ADS)

    Dick, W. R.

    At least 10 astronomers in 5 generations belonged to the Struve dynasty, a family having its origin in Holstein and living in Germany, Russia, the USA and other countries. The best known astronomers among them were Wilhelm (1793-1864), Otto Wilhelm (1819-1905), Hermann (1854-1920), Ludwig (1858-1920), Georg (1886-1933) and Otto Ludwig Struve (1897-1963). After a short account of the family's history, its international relations will be regarded, with emphasis on the following aspects: Nationality/citizenship, places of living and work, personal relations to other astronomers including correspondence and cooperation, travels, languages of publications. Although a comparison of the different members of the family is possible only to a certain degree due to their different role and importance in astronomy, some changes which developed over 150 years can be traced: E.g., Wilhelm Struve published in German, Latin, French, Russian and English, whereas his grandsons and great-grandsons wrote their papers mainly in one language -- German or English. Wilhelm had relatively close relations with French astronomers, whereas his great-grandson Georg was the author of verbal assaults on French scientists. Georg published also heavy criticism of the International Astronomical Union, whereas his cousin Otto Luwig later became IAU's President.

  17. A Teacher is Forever: The Legacy of Harry Kirke Wolfe (1858-1918).

    ERIC Educational Resources Information Center

    Benjamin, Ludy T. Jr.

    1987-01-01

    This article traces the career of Harry Kirke Wolfe, Nebraska educator and one of the earliest U.S. psychologists to earn a doctorate in psychology from Wilhelm Wundt at Leipzig. Emphasis is placed on Wolfe's blending of psychology and pedagogy, and his qualities as a teacher. (Author/JDH)

  18. Creating "Third Spaces": Promoting Learning through Dialogue

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D.

    2010-01-01

    Wilhelm offers us a definition of "third spaces" as "more democratic and dialogic spaces than a classroom, as well as a metaphor for a space in which new, hybrid, and challenging discourses and real-world knowledge and applications are created." With helpful background and examples, he urges us to create such spaces for our students, adamant that…

  19. Academic Freedom: In Justification of a Universal Ideal

    ERIC Educational Resources Information Center

    Karran, Terence

    2009-01-01

    This article examines the justification for, and benefits of, academic freedom to academics, students, universities and the world at large. It surveys the development of the concept of academic freedom within Europe, more especially the impact of the reforms at the University of Berlin instigated by Wilhelm von Humboldt. Following from this, the…

  20. Meeting the Demand: Teaching "Soft" Skills.

    ERIC Educational Resources Information Center

    Wilhelm, William J.; Logan, Joyce; Smith, Sheila M.; Szul, Linda F.

    This document contains four papers (and an introduction by William Wilhelm) on teaching "soft" skills in business education programs. "The Skill Building Challenge: Preparing a Bridge for the Workforce Skills Gap" (Sheila M. Smith) examines the following topics: the workforce skills gap; the importance of academic and behavioral skills; and public…

  1. Alphabet Soup: ERP, CT, and ACT for OCD

    ERIC Educational Resources Information Center

    Tolin, David F.

    2009-01-01

    The present article comments on the case conference presented in this issue, namely, Himle and Franklin's (Himle & Franklin, 2009) exposure and response prevention (ERP); Chosak and colleagues' (Chosak, Marques, Fama, Renaud, & Wilhelm, 2009) cognitive therapy (CT); and (Twohig, 2009) Acceptance and Commitment Therapy (ACT). Two questions are…

  2. Hermeneutics and the Study of Communication.

    ERIC Educational Resources Information Center

    Grossberg, Lawrence; Christians, Clifford G.

    The manner in which hermeneutics (the study of the interpretive process) has treated the phenomenon of interpretation is examined in this paper. Following a historical review of hermeneutics from its Hellenic roots through the phase of traditional hermeneutics to the major reformulation of the field by Friedrich Schleiermacher and Wilhelm Dilthey…

  3. Reading Motivation: Exploring the Elementary Gender Gap

    ERIC Educational Resources Information Center

    Marinak, Barbara A.; Gambrell, Linda B.

    2010-01-01

    In an attempt to more clearly understand the erosion of motivation in some readers, a number of researchers (Mohr, 2006; Smith & Wilhelm, 2002) and organizations (The Education Alliance, 2007) have called for the investigation of gender differences in all readers, including young children. Consequently, this study focused on younger, average…

  4. Bildung as a Powerful Tool in Modern University Teaching

    ERIC Educational Resources Information Center

    Olesen, Mogens Noergaard

    2009-01-01

    In this paper we will demonstrate how powerful "Bildung" is as a tool in modern university teaching. The concept of "Bildung" was originally introduced by the German philosopher Immanuel Kant (Kant 1787, 1798, 1804) and the Prussian lawyer and politician Wilhelm von Humboldt (Humboldt 1792, Bohlin 2008). From 1810 "Bildung" was a key concept in…

  5. Reading Motivation: Exploring the Elementary Gender Gap

    ERIC Educational Resources Information Center

    Marinak, Barbara A.; Gambrell, Linda B.

    2010-01-01

    In an attempt to more clearly understand the erosion of motivation in some readers, a number of researchers (Mohr, 2006; Smith & Wilhelm, 2002) and organizations (The Education Alliance, 2007) have called for the investigation of gender differences in all readers, including young children. Consequently, this study focused on younger, average

  6. Aromatic Interactions in Organocatalyst Design: Augmenting Selectivity Reversal in Iminium Ion Activation.

    PubMed

    Holland, Mareike C; Metternich, Jan Benedikt; Daniliuc, Constantin; Schweizer, W Bernd; Gilmour, Ryan

    2015-07-01

    Invited for the cover of this issue is the group of Ryan Gilmour at the Westfälische Wilhelms-Universität Münster. The image depicts how the modes of stereoinduction differ for- N-methylpyrrole to- N-methylindole. Read the full text of the article at 10.1002/chem.201500270. PMID:25980976

  7. The Origin of the Mole Concept

    ERIC Educational Resources Information Center

    Jensen, William B.

    2004-01-01

    German Chemist, August Wilhelm Hofmann first introduced the term "molar" (from the Latin moles, meaning "a large mass") into chemistry, around 1865. The particular use of the term molar gained currency in the physics literature, where it was in common use at least through the 1940s.

  8. How Principals Cultivate Shared Leadership

    ERIC Educational Resources Information Center

    Wilhelm, Terry

    2013-01-01

    Do teacher leaders in your school mainly fill the traditional roles of department chair or grade-level representative? Or do they lead their peers in collaborative teams whose primary focus is improving student learning? Terry Wilhelm, director of the School Leadership Center for Riverside County Office of Education in California, says that

  9. MERCURY IN PETROLEUM AND NATURAL GAS: ESTIMATION OF EMISSIONS FROM PRODUCTION PROCESSING, AND COMBUSTION: PROJECT REPORT/SUMMARY

    EPA Science Inventory

    NRMRL-RTP-221 Wilhelm, S.M. Mercury in Petroleum and Natural Gas: Estimation of Emissions from Production Processing, and Combustion. 07/19/2001 The report gives results of an examination of mercury (Hg) in liquid and gaseous hydrocarbons that are produced and/or processed i...

  10. Determiner Syntax in Middle Low German: Evidence from the "Luebecker Ratsurteile"

    ERIC Educational Resources Information Center

    Gougeon, Elliott E.

    2012-01-01

    In this dissertation, I take a look at Middle Low German nominal phrases as evidenced in the Lubecker Ratsurteile, a collection of court proceedings published by Wilhelm Ebel in 1955, which cover the years 1421-1550. By digitizing the corpus, I was able to perform a corpus analysis on noun phrases, where I concentrated on determiner use and form,…

  11. "Bildung" and Intercultural Understanding

    ERIC Educational Resources Information Center

    Bohlin, Henrik

    2013-01-01

    The concept of "Bildung", sometimes translated as self-cultivation, is located at the core of an influential tradition of educational thought. A key question concerns the relationship between "Bildung" and interculturality. Drawing on Wilhelm von Humboldt and Hans-Georg Gadamer, and on the so-called transformative learning

  12. Rontgen's Discovery of X Rays

    ERIC Educational Resources Information Center

    Thumm, Walter

    1975-01-01

    Relates the story of Wilhelm Conrad Rontgen and presents one view of the extent to which the discovery of the x-ray was an accident. Reconstructs the sequence of events that led to the discovery and includes photographs of the lab where he worked and replicas of apparatus used. (GS)

  13. EDITORIAL RESPONSE SOME THOUGHTS ON PERENNIAL GRAINS AND POLYCULTURES TO THE NECESSITY AND POSSIBILITY OF PERENNIAL GRAIN PRODUCTION SYSTEMS BY JERRY GLOVER RENEWABLE AGRICULTURE AND FOOD SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Editorial response by Wallace Wilhelm: Some thoughts on perennial grains and polycultures The paper by DeHaan et al. in this issue highlights advantages of perennial grain systems from the standpoint of environmental integrity and soil, water and air quality. They discuss some of the complexity of ...

  14. Zum Ausgleich von generativer und energetischer Sprachbetrachtung (A Comparison of the "Generative" and "Energetic" Views of Language)

    ERIC Educational Resources Information Center

    Weisgerber, Leo

    1972-01-01

    Discussion of two basic conceptions: Wilhelm von Humboldt's idea of language as energeia'' existing within and without man, and Noam Chomsky's idea of language generated by the speaker according to an innate apparatus. Revised version of lectures presented at the University of Bonn, West Germany in August 1971. (RS)

  15. Using Irony in Teaching the History of Psychology.

    ERIC Educational Resources Information Center

    Thorne, B. Michael

    1999-01-01

    Examines historical ironies and stories with surprise endings about Rene Descartes and Wilhelm Wundt that can enliven history of psychology lectures and make certain concepts more memorable. Explains that this approach does not trivialize psychology's history but adds humor to a subject that students sometimes find dull. (CMK)

  16. Proceedings of the Annual Conference of the Western Regional Home Management-Family Economics Educators (25th, Scottsdale, Arizona, November 6-8, 1985).

    ERIC Educational Resources Information Center

    Berry, Ruth E., Ed.

    These proceedings consist of 12 presentations, most of which are followed by responses or comments. The papers include: "Integrating Family Economics and Family Counseling" (Hogan; discussants Schnittgrund, Wilhelm); "A Test of the Deacon-Firebaugh Management Model" (Gage, Schmid); "Perceived Income Adequacy and Selected Financial Management…

  17. Speaking Personally--With Borje Holmberg

    ERIC Educational Resources Information Center

    American Journal of Distance Education, 2011

    2011-01-01

    Borje Holmberg is Swedish and has been active in distance education as a theorist and practitioner for more than fifty years. He is the former president of the Wilhelm-Buchner Hochschule, a distance teaching university in Germany. Here, Holmberg is interviewed by William C. Diehl, the Interviews Editor for "The American Journal of Distance…

  18. Explorations in Regional Variation: A Variational Pragmatic Perspective

    ERIC Educational Resources Information Center

    Barron, Anne

    2015-01-01

    The present article introduces the Special Issue entitled "A Variational Pragmatic Approach to Regional Variation in Language," a collection of papers which celebrates the work of Klaus P. Schneider (Rheinische Friedrich-Wilhelms-Universität Bonn, Germany) on the occasion of his 60th birthday.

  19. Drifting from Slow to "D'oh!": Working Memory Capacity and Mind Wandering Predict Extreme Reaction Times and Executive Control Errors

    ERIC Educational Resources Information Center

    McVay, Jennifer C.; Kane, Michael J.

    2012-01-01

    A combined experimental, individual-differences, and thought-sampling study tested the predictions of executive attention (e.g., Engle & Kane, 2004) and coordinative binding (e.g., Oberauer, Suss, Wilhelm, & Sander, 2007) theories of working memory capacity (WMC). We assessed 288 subjects' WMC and their performance and mind-wandering rates during

  20. The Rhetoric in Mathematics: Newton, Leibniz, the Calculus, and the Rhetorical Force of the Infinitesimal

    ERIC Educational Resources Information Center

    Reyes, G. Mitchell

    2004-01-01

    This essay investigates the rhetoric surrounding the appearance of the concept of the infinitesimal in the seventeenth-century Calculus of Sir Isaac Newton and Gottfried Wilhelm Leibniz. Although historians often have positioned rhetoric as a supplemental discipline, this essay shows that rhetoric is the "material" out of which a new and powerful…

  1. The "Magic" of Music: Archaic Dreams in Romantic Aesthetics and an Education in Aesthetics

    ERIC Educational Resources Information Center

    Kertz-Welzel, Alexandra

    2005-01-01

    The main intent of this article is to describe some opportunities for an education in aesthetics by referring to similarities between intensive experiences of music in the individual life and in the history of aesthetics. Here, the author discusses Romanticism through the writings of Wilhelm Heinrich Wackenroder. Among other things, she discusses…

  2. Academic Freedom: In Justification of a Universal Ideal

    ERIC Educational Resources Information Center

    Karran, Terence

    2009-01-01

    This article examines the justification for, and benefits of, academic freedom to academics, students, universities and the world at large. It surveys the development of the concept of academic freedom within Europe, more especially the impact of the reforms at the University of Berlin instigated by Wilhelm von Humboldt. Following from this, the

  3. Sisyphus at Work: The Leibniz Edition, The Kaiserreich and Divided Germany

    ERIC Educational Resources Information Center

    Poser, Hans

    2004-01-01

    Despite several attempts, the prolific writings of Gottfried Wilhelm Leibniz have not yet been brought together in a single edition. Efforts have been hampered by the sheer volume and diversity of the Leibniz estate, and also by changing political circumstances. This paper traces the history of the Leibniz edition as a long-term project of the

  4. The Academy and the Engineering Sciences: An Unwelcome Royal Gift

    ERIC Educational Resources Information Center

    Konig, Wolfgang

    2004-01-01

    On 19 March 1900, at the bicentenary celebrations of the Prussian Academy of Sciences, Kaiser Wilhelm II established three new fellowships in engineering sciences. This was in many aspects an unwanted gift, and one which tested the Academy's relationship between pure and applied science. In the context of contemporary struggles between traditional

  5. Proactivity vs Reactivity: Preparing Students for Success with CCSS

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D., Ed.

    2012-01-01

    Wilhelm has studied the Common Core State Standards and come away with a generally positive opinion. His concern is that now that the Standards are written, we let professional teachers mold them into the best possible practices for teaching their students. With specific advice for working with students--developing background knowledge, making…

  6. Integrating Fiction and Nonfiction Reading into the Business Classroom

    ERIC Educational Resources Information Center

    Fiene, Judy; Pedersen, Erin

    2013-01-01

    One goal of high school teachers is to help students appreciate that reading does not end when they leave the classroom. When students find reading meaningful, they are more likely to see themselves as readers and choose to read long after they leave the classroom setting (Hinchman, Alvermann, Boyd, Brozo, & Vacca, 2003-2004; Wilhelm, 2001).…

  7. "Bildung" and Intercultural Understanding

    ERIC Educational Resources Information Center

    Bohlin, Henrik

    2013-01-01

    The concept of "Bildung", sometimes translated as self-cultivation, is located at the core of an influential tradition of educational thought. A key question concerns the relationship between "Bildung" and interculturality. Drawing on Wilhelm von Humboldt and Hans-Georg Gadamer, and on the so-called transformative learning…

  8. "The Lengthened Shadow of One Man": The Public Intellectual and the Founding of Universities.

    ERIC Educational Resources Information Center

    Wyatt, John

    1998-01-01

    Identifies five intellectuals who made distinctive contributions to the founding of new universities in England, Germany, and the United States. Institutional and individual biographies profile: Thomas Jefferson (University of Virginia); Wilhelm von Humboldt (University of Berlin); Lord Brougham (University College, University of London); A.D.…

  9. A Poetic Journey: The Transfer and Transformation of German Strategies for Moral Education in Late Eighteenth-Century Dutch Poetry for Children

    ERIC Educational Resources Information Center

    Parlevliet, Sanne; Dekker, Jeroen J. H.

    2013-01-01

    One of the most popular Dutch educational enlightenment authors was Hieronymus van Alphen. His three volumes of "Little Poems for Children" published in 1778 and 1782 were extremely successful, both in the Netherlands and abroad. Inspired by the German poets Christian Felix Weisse and Gottlob Wilhelm Burmann, Van Alphen brought about an…

  10. Einleitung

    NASA Astrophysics Data System (ADS)

    Walther-Klaus, Ellen

    Deutschland hat sich in den letzten Jahrzehnten den internationalen Ruf erworben, auf dem Gebiet der Technologie fhrend zu sein. Groe, weitreichende Erfindungen sind in Deutschland gemacht worden. Viele Nobelpreise gehen nach Deutschland: Robert Bosch, Nikolaus Otto und Konrad Zuse gehren genauso zu den groen Erfindern, wie Melitta Bentz und Emmy Noether. 85 % aller Nobelpreise, die seit 1901 nach Deutschland gingen, sind in den Kategorien Chemie, Physik und Medizin vergeben worden. Allein im Jahr 2007 wurden in Deutschland fast 50.000 Patente angemeldet.

  11. Saturn V Dedication

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Members of the original Von Braun german rocket team participate in the Saturn V replica didication ceremony at the U. S. Space and Rocket Center in Huntsville, AL. Pictured are (L/R): Walter Jacobi, Konrad Dannenberg, Apollo 14's Edgar Mitchell, NASA Administrator Dan Goldin, Apollo 12's Dick Gordon, Gerhard Reisig, Werner Dahm, MSFC Director Art Stephenson, Director of the U. S. Space and Rocket Center Mike Wing, Walter Haeusserman, and Ernst Stuhlinger.

  12. In Memoriam Werner Callebaut.

    PubMed

    Boniolo, Giovanni

    2015-12-01

    The article contains some recollections on Werner Callebaut highlighting his personal character and his role in the community of historians, philosophers and sociologists of the life sciences. Werner Callebaut (1952-2014) was a real European philosopher. He was the Scientific Director of the Konrad Lorenz Institute for Evolution and Cognition Research (KLI, Klosterneuburg, Austria) and the President of the International Society for the History, Philosophy, and Social Studies of Biology. PMID:26350077

  13. Regulatory misconception muddies the ethical waters: challenges to a qualitative study.

    PubMed

    Yee, Kimberly M; Ford, Paul J

    2012-01-01

    In "Potential Subjects' Responses to an Ethics Questionnaire in a Phase I Study of Deep-Brain Stimulation in Early Parkinson's Disease," Finder, Bliton, Gill, Davis, Konrad, and Charles undertake informed consent research on what they describe as a Phase I trial of deep brain stimulation (DBS) for Parkinson's disease. We argue that the authors should have more carefully characterized the nature of the DBS study at the start of their clinical study. PMID:23256401

  14. Comment on ``The First Accurate Description of an Aurora''

    NASA Astrophysics Data System (ADS)

    Silverman, Sam

    2007-11-01

    Schröder [2006] discusses Das Buch der Natur (The Book of Nature), written by Konrad von Megenberg between 1348 and 1350. The Buch was the first encyclopedia of natural phenomena written in German. (For a contemporary German translation, see Schulz [1897] for definitions of Megenberg's astronomical terminology, see Deschler [1977]). Megenberg translated the Liber de Natura Rerum, written by Thomas of Cantimpré between 1225 and 1240.

  15. [Virchow and the cancer of Frederick III].

    PubMed

    Nordlander, N B

    2001-01-01

    Friedrich Wilhelm, born 1831, was the eldest son of Wilhelm I, king of Prussia 1861 and the first German emperor 1871. He was educated in European culture and decided liberal in his political way of thinking and came in opposition to his father, the soldier-king and to the "iron-chancellor" Bismarck, who had the dominant influence over his father and over German politics. One of Friedrich Wilhelms political sympathizer was Rudolf Virchow, the great pathologist, who was also a liberal member of parliament in Prussia and later in Germany. He opposed Bismarcks war-policy, argued in favour of a peaceful unifying of Germany and fought for parliamentary influence on politics and the responsibility of ministers to parliament. Friedrich Wilhelm was doomed to remain crown prince without influence for most of his life, since his father lived unto 91 years of age. The year before he succeeded his father as emperor Friedrich III, he became hoarse and the doctors i.e., the English laryngologist Mackenzie inspected his vocal cords and took a biopsy, which Virchow diagnosed as a benignant inflammatory reaction. Later on it became apparent that the crown prince suffered from cancer. He declined a radical operation as too risky but was soon compelled to have a tracheotomy performed, when he was on the point of being choked by the cancer. During his 99 days as emperor he could only communicate by writing, and he had not power enough left to fulfill his intention to dismiss Bismarck and initiate a liberal policy, including friendship with England - his beloved wife was the eldest daughter of queen Victoria. After his death his son, emperor Wilhelm II, took a quite different course, that led to World War I. If Friedrich III had been a less intensive smoker and not developed cancer, world history might have taken a different course. PMID:11824411

  16. Flight Programs and X-ray Optics Development at MSFC

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; O'Dell, S. L.; Elsner, R.; Kilaru, K.; Atkins, C.; Swartz, D.; Gaskin, J.; Weisskopf, Martin

    2012-01-01

    The X-ray astronomy group at the Marshall Space Flight Center is developing electroformed nickel/cobalt x-ray optics for suborbital and orbital experiments. Suborbital instruments include the Focusing X-ray Solar Imager (FOXSI) and Micro-X sounding rocket experiments and the HERO balloon payload. Our current orbital program is the fabrication of a series of mirror modules for the Astronomical Roentgen Telescope (ART) to be launched on board the Russian-German Spectrum Roentgen Gamma Mission (SRG.) The details and status of these various programs are presented. A second component of our work is the development of fabrication techniques and optical metrology to improve the angular resolution of thin shell optics to the arcsecond-level. The status of these x-ray optics technology developments is also presented.

  17. Teleradiotherapy of joints in rheumatoid arthritis: lack of efficacy

    PubMed Central

    Graninger, M; Handl-Zeller, L; Hohenberg, G; Staudenherz, A; Kainberger, F; Graninger, W

    2005-01-01

    Objective: To determine if the local application of x rays to inflamed joints in rheumatoid arthritis (RA) affects the signs and symptoms of inflammation. Methods: In a randomised, controlled, double blind study, roentgen irradiation was administered in a total dose of 20 Gy during 2 weeks to single joints in six patients with RA who were receiving constant and stable pharmacological treatment with DMARDs and NSAIDs. Single inflamed joints on the contralateral side of the body were used as controls and received sham irradiation. Swelling and tenderness was assessed by blinded investigators before and until 3 months after the irradiation; general disease activity and pain scales were included in the assessment. Results: No change in the scores for tenderness, swelling, pain, or disease activity was seen. The trial was stopped for ethical reasons. Conclusion: Local roentgen treatment of RA at a substantial dose of 20 Gy was ineffective in this pilot trial. PMID:15608312

  18. Prospects for AGN Science using the ART-XC on the SRG Mission

    NASA Technical Reports Server (NTRS)

    Swartz, Douglas A.; Elsner, Ronald F.; Gubarev, Mikhail V.; O'Dell, Stephen L.; Ramsey, Brian D.; Bonamente, Massimiliano

    2012-01-01

    The enhanced hard X-ray sensitivity provided by the Astronomical Roentgen Telescope to the Spectrum Roentgen Gamma mission facilitates the detection of heavily obscured and other hard-spectrum cosmic X-ray sources. The SRG all-sky survey will obtain large, statistically-well-defined samples of active galactic nuclei (AGN) including a significant population of local heavily-obscured AGN. In anticipation of the SRG all-sky survey, we investigate the prospects for refining the bright end of the AGN luminosity function and determination of the local black hole mass function and comparing the spatial distribution of AGN with large-scale structure defined by galaxy clusters and groups. Particular emphasis is placed on studies of the deep survey Ecliptic Pole regions.

  19. Certainty and uncertainty in radiation research

    SciTech Connect

    Kellerer, A.M.

    1996-12-31

    Roentgen`s discovery of x rays marked the end of most of the familiar concepts of physics. A few months later radioactivity was discovered; after a few years quantum theory evolved; and subsequently observations and conclusions were reached that destored the familiar concepts of space, time and even causality. A deterministic world had changed into a shadow world of probabilities. The paradox of determinism and inderminism, certainty and uncertainty, is still central to radiation biology and equally to radiation protection. One task of this paper is to trace this idea from target theory to present problems. The other task is a reassessment of the practical issues; the aims and problems of radiation protection. This issue includes topics of greater dimension: liabilities arising from the weapons production and safeguarding weapons material. 45 refs., 4 figs.

  20. The calibration of flight mirror modules for the ART-XC instrument on board the SRG mission

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Ramsey, B.; Kolodziejczak, J. J.; O'Dell, S. L.; Elsner, R.; Zavlin, V.; Swartz, D.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

    2014-07-01

    MSFC is fabricating x-ray optics for the Astronomical Roentgen Telescope - X-Ray Concentrator (ART-XC or ART for short) instrument under agreements with the Russian Space Research Institute (IKI). ART-XC is one of two instruments that will be launched on the Russian-German Spectrum-Roentgen-Gamma (SRG) Mission to be launched in 20161. Delivery of the flight optics for ART-XC (7 mirror modules) is currently scheduled for summer/fall of 20142. MSFC has to date completed assembly of four modules and has performed extensive calibration on two of these. These calibrations show that the modules meet effective area requirements and greatly exceed the angular resolution requirements. Details of the calibration procedure and an overview of the results obtained to date are presented here.

  1. Tibial bone mineral distribution as influenced by calcium, phosphorus, and vitamin D feeding levels in the growing turkey

    NASA Technical Reports Server (NTRS)

    Spurrell, F. A.; Brenes, J.; Waibel, P.

    1974-01-01

    Roentgen signs, subperiosteal, endosteal, and trabecular bone growth are evaluated in turkeys fed phosphorus at the 0.5, 0.56, 0.68, 0.90, and 2.70 percent levels. Calcium levels of 0.30, 0.40, 0.60, 1.2, and 3.60 percent were also tested. Vitamin D levels of 0, 100, 300, 900 and 27,000 I.U. per day were likewise evaluated. Roentgen signs, bone mineral as measured by T-125 gamma ray absorption, and bone mineral growth patterns as shown by radiograph area projection are correlated with calcium, phosphorus, and vitamin D feeding levels. Differences in bone growth at the various feeding levels were observed which were not reflected by differences in other studied parameters.

  2. The Advanced Photon Source: A national synchrotron radiation research facility at Argonne National Laboratory

    SciTech Connect

    1995-10-01

    The vision of the APS sprang from prospective users, whose unflagging support the project has enjoyed throughout the decade it has taken to make this facility a reality. Perhaps the most extraordinary aspect of synchrotron radiation research, is the extensive and diverse scientific makeup of the user community. From this primordial soup of scientists exchanging ideas and information, come the collaborative and interdisciplinary accomplishments that no individual alone could produce. So, unlike the solitary Roentgen, scientists are engaged in a collective and dynamic enterprise with the potential to see and understand the structures of the most complex materials that nature or man can produce--and which underlie virtually all modern technologies. This booklet provides scientists and laymen alike with a sense of both the extraordinary history of x-rays and the knowledge they have produced, as well as the potential for future discovery contained in the APS--a source a million million times brighter than the Roentgen tube.

  3. Nils Gustav Dalén, the Unknown Nobel Prize Winner

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2009-01-01

    Hanging on the wall of my museum is a large "Map of Physics" published by the Central Scientific Company in 1938. On it is a list of the Nobel Prizes in physics, starting with Roentgen in 1901 and ending with Fermi in 1938. I can recognize every name except the one for 1912: Nils Gustav Dalén. Perhaps you have had the same experience when looking through the updated list.

  4. The premature failure of the Charnley Elite-Plus stem: a confirmation of RSA predictions.

    PubMed

    Hauptfleisch, J; Glyn-Jones, S; Beard, D J; Gill, H S; Murray, D W

    2006-02-01

    We performed a clinical and radiological study to determine the rate of failure of the Charnley Elite-Plus femoral component. Our aim was to confirm or refute the predictions of a previous roentgen stereophotogrammetric analysis study in which 20% of the Charnley Elite-Plus stems had shown rapid posterior head migration. It was predicted that this device would have a high early rate of failure.We examined 118 patients at a mean of nine years after hip replacement, including the 19 patients from the original roentgen stereophotogrammetric study. The number of revision procedures was recorded and clinical and radiological examinations were performed. The rate of survival of the femoral stems at ten years was 83% when revision alone was considered to be a failure. It decreased to 59% when a radiologically loose stem was also considered to be a failure. All the patients previously shown in the roentgen stereophotogrammetric study to have high posterior head migration went on to failure. There was a highly significant difference (p = 0.002) in posterior head migration measured at two years after operation between failed and non-failed femoral stems, but there was no significant difference in subsidence between these two groups. Our study has shown that the Charnley Elite-Plus femoral component has an unacceptably high rate of failure. It confirms that early evaluation of new components is important and that roentgen stereophotogrammetric is a good tool for this. Our findings have also shown that rapid posterior head migration is predictive of premature loosening and a better predictor than subsidence. PMID:16434520

  5. Contributions to the History of Astronomy, Vol. 9; (German Title: Beiträge zur Astronomiegeschichte, Band 9)

    NASA Astrophysics Data System (ADS)

    Dick, Wolfgang R.; Duerbeck, H. W.; Hamel, Jürgen

    The contributions deal with astronomical events of the past 1000 years. We elucidate the person of the single European observer of the supernova of 1006, and the views of Christoph Scheiner and Otto von Guericke on the structure and substance of the cosmos. A study of the development of the Copernican and the cosmological principles conclude this group of themes. Biographical investigations were carried out on the clockmaker Nikolaus Lilienfeld, the astronomers Johann Wurzelbau, Friedrich Wilhelm Toennies and Boris Karpov as well as the “panbabylonist” Alfred Jeremias. Astronomers can be active also in poetry and fiction. This is shown in the studies of Johann Leonard Rost and Friedrich Wilhelm Bessel. Finally, Johannes Hevelius' Observatory in Danzig/Gdansk, destroyed by a fire in 1679, is reconstructed by means of printed sources, old maps and photographs. The book concludes by short communications, obituaries and book reviews.

  6. [Auguste Böhner's death. Chronicle of a medical scandal, its background and its historical significance].

    PubMed

    Wiesing, U

    1989-01-01

    When the 15-year-old Auguste Böhmer, daughter of Caroline Schlegel and stepdaughter of August Wilhelm Schlegel, died on 12th July 1800, Friedrich Wilhelm Joseph Schelling was accused of being responsible for this tragic event, because he tried to treat her according to the medical system of John Brown. The ensuing scandal became a symbol for the danger of every progressive movement of that time: the Romantic literature, the natural philosophy of Schelling and Brownianism in its German version, represented by Andreas Röschlaub. An attempt is made to analyse the social and political background of the scandal and to argue the historical meaning as a fight against a fundamental reform of medicine. PMID:2700022

  7. The role of tone sensation and musical stimuli in early experimental psychology.

    PubMed

    Klempe, Sven Hroar

    2011-01-01

    In this article, the role of music in early experimental psychology is examined. Initially, the research of Wilhelm Wundt is considered, as tone sensation and musical elements appear as dominant factors in much of his work. It is hypothesized that this approach was motivated by an understanding of psychology that dates back to Christian Wolff 's focus on sensation in his empirical psychology of 1732. Wolff, however, had built his systematization of psychology on Gottfried Wilhelm von Leibniz, who combined perception with mathematics,and referred to music as the area in which sensation is united with numerical exactitude. Immanuel Kant refused to accept empirical psychology as a science, whereas Johann Friedrich Herbart reintroduced the scientific basis of empirical psychology by, among other things, referring to music. PMID:21462196

  8. A note on the history of the Norwegian Psychoanalytic Society from 1933 to 1945.

    PubMed

    Anthi, Per; Haugsgjerd, Svein

    2013-08-01

    The Norwegian analysts, who were trained in Berlin before 1933, were drawn into a struggle against fascism, informed by politically leftist analysts who worked at the Berlin Institute. The Norwegian group, including the analysts Wilhelm Reich and Otto Fenichel, were committed to Marxist or social democratic ideologies in order to fight down fascism and Nazism. They were a source of inspiration but also of conflict. After the war the leadership of the IPA was sceptical about the Norwegian group because of its former connections with Die Linke, as well as its relations with Wilhelm Reich. This paper in part considers the courageous efforts of Nic Waal, whom Ernest Jones used as a delegate and courier to solve problems for the IPA and who was unjustly treated after the war. PMID:23924331

  9. Otto Hahn: Responsibility and Repression

    NASA Astrophysics Data System (ADS)

    Walker, Mark

    2006-05-01

    The role that Otto Hahn (1879 1968) played in the discovery of nuclear fission and whether Lise Meitner (1878 1968) should have shared the Nobel Prize for that discovery have been subjects of earlier studies, but there is more to the story. I examine what Hahn and the scientists in his Kaiser Wilhelm Institute for Chemistry in Berlin-Dahlem did during the Third Reich, in particular, the significant contributions they made to the German uranium project during the Second World War. I then use this as a basis for judging Hahn’s postwar apologia as the last president of the Kaiser Wilhelm Society and first president of its successor, the Max Planck Society.

  10. The Politics of Memory: Otto Hahn and the Third Reich

    NASA Astrophysics Data System (ADS)

    Sime, Ruth Lewin

    2006-03-01

    As President of the Kaiser Wilhelm Society and its successor, the Max Planck Society, from 1946 until 1960, Otto Hahn (1879 1968) sought to portray science under the Third Reich as a purely intellectual endeavor untainted by National Socialism. I outline Hahn’s activities from 1933 into the postwar years, focusing on the contrast between his personal stance during the National Socialist period, when he distinguished himself as an upright non-Nazi, and his postwar attitude, which was characterized by suppression and denial of Germany’s recent past. Particular examples include Hahn’s efforts to help Jewish friends; his testimony for colleagues involved in denazification and on trial in Nuremberg; his postwar relationships with émigré colleagues, including Lise Meitner; and his misrepresentation of his wartime work in the Kaiser Wilhelm Institute for Chemistry.

  11. Hufeland's interest in plant movements.

    PubMed

    Aschoff, J

    1991-01-01

    Christoph Wilhelm Hufeland (1762-1836) was one of the eminent physicians at the time of Goethe. When only 21 years old, he followed his father as a medical practitioner in Weimar. In 1793 he became Professor of Medicine at the University of Jena, from where he moved, in 1801, to Berlin as the physician in ordinary to king Friedrich Wilhelm III, council of state, and Professor at the leading hospital, the Charité. Hufeland pioneered in what today would be called public hygiene. Many of his lectures and publications were addressed to the educated laymen. In his most read book, the 'Makrobiotik', he emphasizes the importance of the 24-h periodicity as a basic unit of biological chronometry. In view of this, Hufeland has become a kind of 'patron saint' to modern chronobiologists. PMID:1760962

  12. Jewish gynecologists in Germany in the first half of the twentieth century.

    PubMed

    Rudloff, Udo; Ludwig, Hans

    2005-10-01

    The political changes in Germany of 1933 led to discrimination, expulsion and emigration of Jewish doctors. This article addresses the memory of gynecologists who were eminent physicians or made fundamental discoveries. Short biographies of Ludwig Fraenkel, Selmar Aschheim, Bernhard Zondek, Ludwig Adler, Robert Meyer and Paul Ferdinand Strassmann highlight their work and their links to the Gynecological Society in Berlin and to the German Society of Gynecology, the foundation of the latter being inspired by Wilhelm Alexander Freund from Strasbourg. PMID:16086229

  13. Bone remodelling: should we cry Wolff?

    PubMed

    Lee, T C; Taylor, D

    1999-01-01

    Wolff's Law describes the relationship between the structure and function of bone. Julius Wolff based his law on a comparison of the stress trajectories in Culmann's crane with the pattern of trabecular bone in the femoral neck. However, his analysis was based on a misinterpretation of mechanical data and a rejection of bone resorption. Wilhelm Roux was the first to accurately describe the adaptation of bone to altered load, so Roux's Law would be a more accurate eponym. PMID:10422387

  14. [Historical development of anthropology in Basel].

    PubMed

    Bay, R

    1986-12-01

    The author reports on the history of physical anthropology in Basel (Switzerland). The anthropological research activities of Carl Gustav Jung (1794-1864), Wilhelm His-Vischer (1831-1904), Ludwig Rütimeyer (1825-1895), Julius Kollmann (1834-1918), Paul and Fritz Sarasin (P.: 1856-1924; F.: 1859-1942), Felix Speiser (1880-1949) and the author himself (b. 1909) are described in detail. PMID:3548583

  15. Introductory talk

    NASA Astrophysics Data System (ADS)

    Siegbahn, Kai

    1996-01-01

    A brief historical review is given of the discovery of x-rays by Wilhelm Conrad Röntgen in Würzburg in 1895 and the time following the discovery. X-ray spectroscopy was during the twenties and thirties a flourishing field of research at the institute of physics in Uppsala. During the time after the second world war the research has been redirected to fields which are connected to the original discovery of the X-radiation.

  16. The first 50 years of military radiology 1895-1945.

    PubMed

    Thomas, Adrian M K

    2007-08-01

    Following the discovery of X-rays in 1895 by Wilhelm Röntgen the value to the military surgeon of the new technique was soon realised. The localisation of retained bullets by radiography avoided inappropriate exploration of the wound. The X-rays were first used on casualties from the Abyssinian War of 1896 and the developing radiological technology was progressively applied to military surgery. In addition the needs of warfare stimulated the development of all aspects of radiology. PMID:17629432

  17. An unprecedented sensation-public reaction to the discovery of X-rays

    NASA Astrophysics Data System (ADS)

    Schedel, A.

    1995-11-01

    Since discoveries in physics are usually spread via technical journals, they are rarely the focus of public interest. It was different with Wilhelm Rontgen`s preliminary communication, On a new kind of rays. On 5 January 1896 a report in the Vienna Presse succeeded in bringing the Wurzburg X-rays to the attention of popular newspapers, magazines and finally to the experts as well.

  18. Olbers studies. With three unpublished manuscripts by Olbers.

    NASA Astrophysics Data System (ADS)

    Jaki, S. L.

    The name of Wilhelm Olbers (1758 - 1840), a physician-astronomer from Bremen, suddenly moved into the focus of cosmological awareness in the late 1940s. The first to probe into the reason of this development was the author of these studies, by a series of essays on Olbers, most of which have so far appeared only in German, and which are presented in translation here. This volume also publishes for the first time in English three papers left by Olbers in manuscript.

  19. History of the Oral and Maxillofacial Surgery Residency Program at Universidad el Bosque, Bogotá, Colombia.

    PubMed

    Castro-Núñez, Jaime

    2012-01-01

    The formal training of oral and maxillofacial surgeons in Colombia started in 1958 at Hospital Sanjos6, thanks to the titanic work of Waldemar Wilhelm, a German-born surgeon who settled in BogotA in 1950. Today there are seven institutions in Colombia that offer residency programs in oral and maxillofacial surgery. The aim of this article is to describe the history of the Oral and Maxillofacial Surgery Residency Program at Universidad El Bosque in Bogota. PMID:22916408

  20. A neutron scattering study of the crystal and magnetic structure of Sr2CrOsO6

    NASA Astrophysics Data System (ADS)

    Krockenberger, Y.; Reehuis, M.; Tovar, M.; Mogare, K.; Jansen, M.; Alff, L.

    2007-03-01

    Recently, the new osmium-based ferrimagnetic double perovskite Sr2CrOsO6 has been reported to have the highest Curie temperature (˜725 K) within this material class [Y. Krockenberger, K. Mogare, M. Reehuis, M. Tovar, M. Jansen, G. Vaitheeswaran, V. Kanchana, A. Delin, F. Wilhelm, A. Rogalev, A. Winkler, L. Alff, preprint, 2006]. Here, we report details about the crystal and magnetic structure of Sr2CrOsO6 as obtained by neutron powder diffraction.

  1. Clinical imprinting: the impact of early clinical learning on career long professional development in nursing.

    PubMed

    Andrew, Nicola

    2013-05-01

    The literature recognises a relationship between clinical experience and a successful undergraduate experience in nursing; however what constitutes an effective approach remains the subject of debate, particularly in relation to first year of learning. There is evidence from a biological standpoint that early experience impacts on the behavioural development of animals, described by Konrad Lorenz (1903-1989) as 'imprinting'. The concept of imprinting has resonance for nursing. In this article the importance of 'getting it right at the beginning' is explored and what, if anything, Lorenz's theory tells us about the impact of early clinical learning on subsequent professional development. PMID:22975293

  2. The first accurate description of an aurora

    NASA Astrophysics Data System (ADS)

    Schröder, Wilfried

    2006-12-01

    As technology has advanced, the scientific study of auroral phenomena has increased by leaps and bounds. A look back at the earliest descriptions of aurorae offers an interesting look into how medieval scholars viewed the subjects that we study.Although there are earlier fragmentary references in the literature, the first accurate description of the aurora borealis appears to be that published by the German Catholic scholar Konrad von Megenberg (1309-1374) in his book Das Buch der Natur (The Book of Nature). The book was written between 1349 and 1350.

  3. PREFACE: Preface

    NASA Astrophysics Data System (ADS)

    Moffatt, Keith; Kephart, Thomas

    2014-10-01

    This online volume contains a selection of papers arising from two workshops organised within the six-month programme Topological Dynamics in the Physical and Biological Sciences held at the Isaac Newton Institute for Mathematical Sciences, Cambridge, from July to December 2012. The first of these was a 'satellite workshop' held at the International Centre for Mathematical Sciences (ICMS), Edinburgh, 15-19 October 2012, under the title Tangled Magnetic Fields in Astro- and Plasma Physics, and with Scientific Organising Committee: Konrad Bajer (Warsaw), Mitchell Berger (Exeter), Steve Cowley (Culham Centre for Fusion Energy), Andrew Gilbert (Exeter), Gunnar Hornig (Dundee), and Clare Parnell (St Andrews). The second was the workshop Quantised Flux in Tightly Knotted and Linked Systems held at the Newton Institute, 3- 7 December 2012, with Scientific Organising Committee: Natalia Berloff (DAMTP, Cambridge), Anne-Christine Davis (DAMTP, Cambridge), Jason Cantarella (University of Georgia), Thomas Kephart (Vanderbilt University), Paul Sutcliffe (Durham University), and Tanmay Vachaspati (Arizona State University). Videos of the lectures given at this second workshop can be viewed at http://www.newton.ac.uk/webseminars. The papers published here follow a natural progression through the following topics: helicity and related invariants of magnetic fields in ideal MHD; relaxation under topological constraints; lower bounds on magnetic energy; current and vortex filaments; applications in the solar corona, tokamak plasmas, and cyclone dynamics; higher-order invariants; topology of curves and surfaces, and energy measures; tight knots; applications to Bose-Einstein condensates, QCD, and cosmic superstring theory. Some of the papers span more than one of these areas. We owe a great debt of gratitude to Konrad Bajer, who was one of the guiding spirits behind the whole Newton Institute program, and who took particular responsibility for the Satellite Workshop at ICMS, Edinburgh. Konrad fell seriously ill in June 2014, having completed much of the editorial work for these Proceedings. Following an operation at the end of July, he remained optimistic of a complete recovery, but sadly this was not to be, and he died from a particularly malignant form of cancer on 29th August. The funeral was held in Warsaw on 5th September. Konrad's warmth of personality and generosity of spirit will be remembered by all who participated in these workshops and in the wider Newton Institute program. The Isaac Newton Institute provided an ideal environment for informal interactions before and after both these workshops. We wish to express our thanks to the Director and staff of the Institute for their tireless efforts to ensure the success of the whole program; also to the staff of ICMS, Edinburgh, for their expert hosting of the satellite workshop.

  4. Disposal of LLW and ILW in Germany - Characterisation and Documentation of Waste Packages with Respect to the Change of Requirements

    SciTech Connect

    Bandt, G.; Spicher, G.; Steyer, St.; Brennecke, P.

    2008-07-01

    Since the 1998 termination of LLW and ILW emplacement in the Morsleben repository (ERAM), Germany, the treatment, conditioning and documentation of radioactive waste products and packages have been continued on the basis of the waste acceptance requirements as of 1995, prepared for the Konrad repository near Salzgitter in Lower Saxony, Germany. The resulting waste products and packages are stored in interim storage facilities. Due to the Konrad license issued in 2002 the waste acceptance requirements have to be completed by additional requirements imposed by the licensing authority, e. g. for the declaration of chemical waste package constituents. Therefore, documentation of waste products and packages which are checked by independent experts and are in parts approved by the responsible authority (Office for Radiation Protection, BfS) up to now will have to be checked again for fulfilling the final waste acceptance requirements prior to disposal. In order to simplify these additional checks, databases are used to ensure an easy access to all known facts about the waste packages. A short balance of the existing waste products and packages which are already checked and partly approved by BfS as well as an overview on the established databases ensuring a fast access to the known facts about the conditioning processes is presented. (authors)

  5. Radiation physics and applications in therapeutic medicine

    NASA Astrophysics Data System (ADS)

    Oldham, Mark

    2001-11-01

    Radiation therapy is an example of the successful application of advanced physics to the treatment of human disease leading to improved quality of life and even cure for many patients. The German physicist William Roentgen (1845-1923), who discovered x-rays in 1895 and pioneered early x-ray applications, would likely be astonished if he could see the breadth and depth of their application in the modern hospital setting. This article gives an overview of some modern applications of high energy radiation beams in therapeutic medicine and the underlying physics which forms the basis of their curative effects.

  6. Medical physics: some recollections in diagnostic X-ray imaging and therapeutic radiology.

    PubMed

    Gray, J E; Orton, C G

    2000-12-01

    Medical physics has changed dramatically since 1895. There was a period of slow evolutionary change during the first 70 years after Roentgen's discovery of x rays. With the advent of the computer, however, both diagnostic and therapeutic radiology have undergone rapid growth and changes. Technologic advances such as computed tomography and magnetic resonance imaging in diagnostic imaging and three-dimensional treatment planning systems, stereotactic radiosurgery, and intensity modulated radiation therapy in radiation oncology have resulted in substantial changes in medical physics. These advances have improved diagnostic imaging and radiation therapy while expanding the need for better educated and experienced medical physics staff. PMID:11110920

  7. Design and performance of the 1. 5 MV injector for FXR

    SciTech Connect

    Kulke, B.; Ravenscroft, D.S.; Vogtlin, G.E.

    1981-03-04

    The new flash x-ray machine (FXR) at LLNL is scheduled for completion in late 1981. This is a 54 module, linear induction accelerator, designed to deliver 500 Roentgen at 1 m as bremsstrahlung from a 20 MeV, 4 kA, 60 ns pulsed electron beam. The 1.5 MV, cold cathode injector makes use of six accelerator modules as voltage sources. High voltage testing of the accelerator modules and their associated pulse forming lines and Marx banks has been completed, and beam tests of the complete injector assembly are in progress. Design information and preliminary test results are presented.

  8. Forty years of Galilean Electromagnetism (1973-2013)

    NASA Astrophysics Data System (ADS)

    Rousseaux, Germain

    2013-08-01

    We review Galilean Electromagnetism since the 1973 seminal paper of Jean-Marc Lévy-Leblond and Michel Le Bellac and we explain for the first time all the historical experiments of Rowland, Vasilescu Karpen, Roentgen, Eichenwald, Wilson, Wilson and Wilson, which were previously interpreted in a Special Relativistic framework by showing the uselessness of the latter for setups involving slow motions of a part of the apparatus. Galilean Electromagnetism is not an alternative to Special Relavity but is precisely its low-velocity limit in Classical Electromagnetism.

  9. Evaluation of adsorbed dose in mammography: Monte Carlo simulation studies

    SciTech Connect

    Doi, K.; Chan, H.P.

    1980-04-01

    Computer programs for calculation of the backscatter factor and absorbed dose in breast phantoms are developed based on Monte Carlo simulation. Rad/roentgen conversion factors are calculated for water, fat, a mixture of 50% water and 50% fat, and lucite irradiated with monoenergetic and polyenergetic x rays from a tungsten or molybdenum anode x-ray tube. These factors can be used to estimate skin dose, average depth dose, or average inegral dose in a breast when the beam quality, exposure in air at the skin position, and composition of the breast are known. Calculated backscatter factors are considerably greater than measured values reported previously.

  10. What can be Learned from X-ray Spectroscopy Concerning Hot Gas in Local Bubble and Charge Exchange Processes?

    NASA Technical Reports Server (NTRS)

    Snowden, Steve

    2007-01-01

    What can be learned from x-ray spectroscopy in observing hot gas in local bubble and charge exchange processes depends on spectral resolution, instrumental grasp, instrumental energy band, signal-to-nose, field of view, angular resolution and observatory location. Early attempts at x-ray spectroscopy include ROSAT; more recently, astronomers have used diffuse x-ray spectrometers, XMM Newton, sounding rocket calorimeters, and Suzaku. Future observations are expected with calorimeters on the Spectrum Roentgen Gamma mission, and the Solar Wind Charge Exchange (SWCX). The Geospheric SWCX may provide remote sensing of the solar wind and magnetosheath and remote observations of solar CMEs moving outward from the sun.

  11. A simulation environment for estimation of the performance of RSA cages.

    PubMed

    Gammuto, M; Martelli, S; Trozzi, C; Bragonzoni, L; Russo, A

    2008-09-01

    Roentgen stereophotogrammetric analysis (RSA) is an important technique for in vivo evaluation of joint kinematics and surgical outcome. However, its accuracy is highly affected by the experimental set-up. In this paper we present a new software environment for assessing the impact of calibration cage design on the accuracy of the reconstruction of 3D points, which can be easily used for preliminary evaluations also by non-expert users. The paper presents methods of the simulator and preliminary results in a clinical standard and custom environment. The software was realized using MATLAB and developed for the PC/Windows operating system. It is freeware under request to authors. PMID:18752797

  12. Effect of varying ventricular function by extrasystolic potentiation on closure of the mitral valve.

    NASA Technical Reports Server (NTRS)

    Vandenberg, R. A.; Williams, J. C. P.; Sturm, R. E.; Wood , E. H.

    1971-01-01

    Mitral regurgitant indexes were measured by roentgen videodensitometry in anesthetized dogs without thoracotomy before, during and after extrasystolic potentiation of ventricular contraction while the atria and ventricles were driven in normal temporal sequence simultaneously or in such a way as to induce atrial fibrillation. Small amounts of mitral reflux were observed with simultaneous atrial and ventricular driving and with atrial fibrillation in the control measurements before initiation of extrasystolic potentiation. Reflux became negligible during extrasystolic potentiation and increased beyond control levels after termination of extrasystolic potentiation.

  13. A soft X-ray image of the moon

    NASA Technical Reports Server (NTRS)

    Schmitt, J. H. M. M.; Aschenbach, B.; Hasinger, G.; Pfeffermann, E.; Snowden, S. L.

    1991-01-01

    A soft X-ray image of the moon obtained by the Roentgen Observatory Satellite ROSAT clearly shows a sunlit crescent, demonstrating that the moon's X-ray luminosity arises from backscattering of solar X-rays. The moon's optically dark side is also X-ray dark, and casts a distinct shadow on the diffuse cosmic X-ray background. Unexpectedly, the dark side seems to emit X-rays at a level about one percent of that of the bright side; this emission very probably results from energetic solar-wind electrons striking the moon's surface.

  14. A review of pre-clinical testing of femoral stem subsidence and comparison with clinical data.

    PubMed

    Gheduzzi, S; Miles, A W

    2007-01-01

    Immediate postoperative stability of femoral stems is one of the key factors for the long-term success of total hip replacement. The need to develop a reliable technique to assess in vitro implant stability under physiological loading conditions is widely recognized. A critical review of the in vitro techniques developed for the assessment of implant stability is presented. In vitro predictions of subsidence are compared to in vivo clinical data available from Roentgen stereophotogrammetric analysis (RSA) studies. Limited correlation between in vitro predictions of stability and clinical measurements of subsidence obtained through RSA data was found even though similar migration patterns could be distinguished. PMID:17315767

  15. Accurate assessment of patellar tracking using fiducial and intensity-based fluoroscopic techniques.

    PubMed

    Tang, T S Y; MacIntyre, N J; Gill, H S; Fellows, R A; Hill, N A; Wilson, D R; Ellis, R E

    2004-09-01

    Accuracies of a point-based and an intensity-based fluoroscopic methods of assessing patella tracking were determined by comparing the pattern of patellar motion with respect to orientation (flexion, internal rotation, and lateral tilt) and translation (lateral, proximal, and anterior) with the pattern of patellar motion measured using Roentgen stereophotogrammetric analysis in three cadaver knee specimens. Each pose in the patellar motion could be obtained from single as well as multiple calibrated fluoroscopic images. The errors using the intensity-based method were slightly higher than those of the point-based method, but they appear to be sufficiently low to detect clinically significant differences in patellar kinematics. PMID:15450227

  16. eROSITA - Nearby Young Stars in X-rays

    NASA Astrophysics Data System (ADS)

    Robrade, J.

    2016-01-01

    X-ray surveys are well suited to detect, identify and study young stars based on their high levels of magnetic activity and thus X-ray brightness. The eROSITA instrument onboard the Spectrum-Roentgen-Gamma (SRG) satellite will perform an X-ray all-sky survey that surpasses existing data by a sensitivity increase of more than an order of magnitude. The 4 yr survey is expected to detect more than half a million stars and stellar systems in X-rays.

  17. Wundt, Vygotsky and Bandura: a cultural-historical science of consciousness in three acts.

    PubMed

    Ferrari, Michel; Robinson, David K; Yasnitsky, Anton

    2010-01-01

    This article looks at three historical efforts to coordinate the scientific study of biological and cultural aspects of human consciousness into a single comprehensive theory of human development that includes the evolution of the human body, cultural evolution and personal development: specifically, the research programs of Wilhelm Wundt, Lev Vygotsky and Albert Bandura. The lack of historical relations between these similar efforts is striking, and suggests that the effort to promote cultural and personal sources of consciousness arises as a natural foil to an overemphasis on the biological basis of consciousness, sometimes associated with biological determinism. PMID:21033206

  18. On an early proposal for a unified system of units

    NASA Astrophysics Data System (ADS)

    Mendelson, Kenneth S.

    2015-02-01

    In the present SI system, the units of length and time are related by defining the speed of light as exactly 299,792,458 m/s. In 1857, Wilhelm Weber and Rudolf Kohlrausch proposed a system of units in which the units of length and time were also related by defining a speed, although not the speed of light. The system was extended to include a unit of mass. The Weber-Kohlrausch system was impractical and was apparently never adopted. Nevertheless, it remains of historical interest as an early attempt at a systematic treatment of physical units.

  19. Vienna University Observatory and Bruno Thüring (German Title: Die Wiener Universitätssternwarte und Bruno Thüring )

    NASA Astrophysics Data System (ADS)

    Kerschbaum, Franz; Posch, Thomas; Lackner, Karin

    We investigate Bruno Thüring's political attitude during the time of National Socialism, based on material from the Vienna Observatory archive, and on statements by his contemporaries. The contribution focuses on the filling of astronomy positions in Vienna, and also on the expulsion of Kasimir Graff. A central role is played by Wilhelm Führer, Obersturmführer der Waffen-SS (Senior Storm Leader of the Armed Protection Squad) and chief civil servant in the Reich science ministry. The transcription of an original letter of 1939 by Führer, addressed to Thüring, is given.

  20. Production of Penicillic Acid and Ochratoxin A on Poultry Feed by Aspergillus ochraceus: Temperature and Moisture Requirements

    PubMed Central

    Bacon, C. W.; Sweeney, J. G.; Robbins, J. D.; Burdick, D.

    1973-01-01

    A strain of Aspergillus ochraceus Wilhelm, isolated from poultry feed, produced both penicillic acid and ochratoxin A. Studies demonstrating the ability of this fungus to colonize poultry feed and produce these two mycotoxins under various temperatures and moistures indicated that the interaction was complex. The optimal temperature for conidial development did not vary with moisture, but accumulation of both toxins did. A combination of low temperature, 15 or 22 C, and low moisture favored the production of penicillic acid, whereas high temperature, 30 C, and high moisture favored the production of ochratoxin A. PMID:4795527

  1. Max Bielschowsky (1869-1940).

    PubMed

    Stahnisch, F W

    2015-03-01

    Berlin neurologist and neurohistologist Max Bielschowsky counts among the most innovative microanatomical researchers at the beginning of the twentieth century. Although being quite underrated in the history of neurology today, Bielschowsky contributed substantially to the understanding of neurohereditary pathologies, such as Alzheimer's disease, Parkinsonism, and Huntington's chorea, as well as the assessment of structural changes in several movement disorders. Working with other leading research neurologists, such as Oskar and Cecile Vogt or Korbinian Brodmann at the newly founded Kaiser Wilhelm Institute for Brain Research in Berlin-Buch, he also pioneered neurohistological work on de- and regeneration processes in the Central Nervous System along with new morphological definitions of "nervous trauma." PMID:25346063

  2. Bach and His.

    PubMed

    Beasley, Wyn

    2014-12-01

    This paper examines the career of Johann Sebastian Bach (1685-1750) and the role played by Wilhelm His I (who was, with Albert von Haller, a noted pioneer of physiology) in the exhumation of Bach's remains in 1894. His's examination of these remains allowed the sculptor Carl Seffner to produce the celebrated statue of Bach which stands outside the church of St Thomas in Leipzig, where the composer was employed from 1723 until his death. Modern forensic techniques have recently enabled Bach's image to be reconstructed in even more spectacular detail. PMID:24405850

  3. Hyphenated history: Erb-Duchenne brachial plexus palsy.

    PubMed

    Schmitt, Carrie; Mehlman, Charles T; Meiss, A Ludwig

    2008-07-01

    Throughout history, the discoveries of their predecessors have led physicians to revolutionary advances in the understanding and practice of medicine. The result is a plethora of hyphenated eponyms paying tribute to individuals connected through time by a common interest. The history of Guillaume Duchenne de Boulogne, the "father of electrotherapy and electrodiagnosis," and Wilhelm Heinrich Erb, the "father of neurology," offers insight into the personal and professional lives of these astute clinicians and their collaborative medical breakthrough in the area of neurologic paralysis affecting the upper limbs. PMID:18795182

  4. Eugen von Gothard and His X-Ray Experiments

    NASA Astrophysics Data System (ADS)

    Vincze, Ildikó J.; Jankovics, István

    2010-03-01

    Eugen von Gothard (1857-1909) made significant contributions to astrophysics and founded the Astrophysical Observatory in Herény, Hungary, in 1881. He also was a gifted instrument maker who designed and produced the apparatus and equipment he needed to carry out his researches, which enabled him to respond immediately to Wilhelm Conrad Röntgen’s astonishing discovery of X rays. Von Gothard took his first X-ray photograph on January 23, 1896, thus inaugurating his first series of experiments, which ended on May 26, 1896. He carried out a second series of experiments on June 21-22, 1905, four years before his premature death at age 51.

  5. A Special Sort of Forgetting: Negation in Freud and Augustine.

    PubMed

    Rosengart, Daniel

    2016-04-01

    The development from a positive, dualistic theory of memory and forgetting to a concept of memory that includes forgetting as a variety of remembering is traced in two thinkers. Freud's concept of repression is discussed as a complex negation of both remembering and forgetting, and the development of this construct is shown in his letters to Wilhelm Fliess. A close reading of Augustine of Hippo's Confessions shows a similar concept of a special sort of forgetting, in which what is forgotten is remembered nonetheless. Finally, the limits of the comparison are discussed, and a reading of Freud's "Negation" reveals ways in which the unconscious is fundamentally unlike Augustine's interiority. PMID:27009296

  6. Geologic Map of Part of the Western Hellas Planitia, Mars

    USGS Publications Warehouse

    Moore, Jeffrey M.; Wilhelms, Don E.

    2007-01-01

    Introduction Rock units were deposited on Mars by meteorite impact, volcanism, wind, flowing water, standing water, and ice, acting separately or in concert. Hellas Planitia, the deepest tract on Mars, is a broad depression lying within the high-rimmed, approximately 2,300-km-wide Hellas impact basin. The basin and the planitia are centered about 250 km east of the southeast corner of the map area. Like other stratigraphy-based planetary mapping (Wilhelms, 1990), we suggest the most likely origins for age relations and morphologies visible in the map area.

  7. Recent notes on Tycho Brahe's library

    NASA Astrophysics Data System (ADS)

    Gingerich, Owen

    Wilhelm Norlind lists 216 books presumed to have been in Tycho's library, but the actual count must have been much higher. The largest block of surviving books are in the Clementinum in Prague, just over 50 volumes but nearly 100 titles. Tycho tried to acquire books in many ways, and particularly by buying the library of Paul Wittich after the death of this one-time visitor to Hven. This talk will also describe two annotated volumes from Tycho's library that have recently come onto the antiquarian market: Apianus' Astronomicum Caesareum (Ingolstadt, 1540) and Cornelius Gemma's De naturae divinis characterismis (Antwerp, 1575).

  8. [The I.G. Farben laboratory at the Günzburg mental hospital. Epilepsy research during the NS-regime and the postwar period].

    PubMed

    Söhner, Felicitas; Winckelmann, Hans-Joachim; Becker, Thomas

    2015-01-01

    The purpose of this study is to evaluate the activities of the I.G. Farben laboratory at the former "Heil- und Pflegeanstalt" Günzburg. This laboratory was established to test the newly developed epilepsy drug "Citrullamon" and its derivatives. Specifically, the type and manner of the various experiments were examined to determine whether the suspicions of unethical human experimentation could be identified. The commercial and medical activities between I.G. Farben and the Heil- und Pflegeanstalt, including the specific roles of the senior physician Wilhelm Leinisch and the I.G. Farben chemist Arno Grosse, are reviewed. PMID:26536788

  9. [The Malady of Emperor Frederick III. and Virchow's diagnostic role].

    PubMed

    Sedivy, Roland

    2015-04-01

    Crownprince Frederick Wilhelm of Prussia was once the hope of the liberal movement in Germany. He embodied and lived a humanistic ideal based on the spirit of the enlightenment. Starting in January 1887 the passionate pipe smoker suffered on an unusual long hoarseness. A polyp of the vocal cord was diagnosed. Although this diagnosis seemed harmless, an odyssee was launched that made history. Rudolf Virchow-the foremost pathologist of that time-was involved in the following histological diagnosis. His role and that of the sprouting histopathology will be presented in this essay. PMID:25925224

  10. Three new species of Kerevata (Braconidae: Rogadinae: Clinocentrini) from mainland Papua New Guinea.

    PubMed

    Butcher, Buntika Areekul; Quicke, Donald L J

    2014-01-01

    Three new species of the distinctive, cyclostome, braconid wasp genus Kerevata (viz. Kerevata jamesmayi sp. nov., K. clarksoni sp. nov. and K. hammondi sp. nov.) from Mt Wilhelm, Madang Province, Papua New Guinea are described and illustrated, and a key provided to enable their identification and separation from the only other species described to date, K. pacifica, from New Britain in the Bismark Archipelago off the S. E. coast of New Guinea. Characters used to differentiate Kerevata from the related Confusocentrus are modified. PMID:24943171

  11. The onset of labour: an alternative theory.

    PubMed

    Jones, P

    1996-02-01

    This article, based mainly on the theories and discoveries of Wilhelm Reich (1897-1957), puts forward the bio-energetic theory of the onset of labour, which assumes it to be one of many examples of bio-energetic pulsation in the organism. It suggests that chronic muscular tension ('armouring') interferes with this spontaneous pulsation and may account for many of the difficulties experienced by women in labour. A form of psychotherapy ('orgone-therapy') based on these theories may prove helpful in childbirth education, in the non-intrusive induction of labour, and in labour itself. A research project to test this hypothesis is suggested. PMID:9439268

  12. [Habitus, capital and fields: the search for an acting head of the Hamburg Asylum Friedrichsberg in 1897].

    PubMed

    Sammet, Kai

    2005-01-01

    In 1897 Hamburg was in search of an Oberarzt for the asylum Friedrichsberg who should function as the acting head of the head Wilhelm Reye (1833-1912). This search was part of the intended reformation of the outmoded psychiatric care in Hamburg. During this application procedure the Hamburg Physikus John Wahncau examined all possible candidates and applicants. The article explores the election process by using some sociological categories developed by Pierre Bourdieu (habitus, capital, field). The author argues that not only meritocratic attributes led to the choice of one candidate, but also his functional "fitting" into the field in Hamburg. PMID:16201321

  13. A structural and intertextual reading of Freud's "On Dreams".

    PubMed

    Mahlendorf, U

    2000-04-01

    By using the framework of a "quest" narrative based on literary allusions to Virgil's Aeneid and Goethe's Wilhelm Meister's Apprenticeship, Freud transformed the 500 pages of The Interpretation of Dreams into some fifty pages entitled "On Dreams." This paper elucidates the narrative means by which Freud achieved the feat of turning a highly complex, lengthy theoretical work into an engaging narrative. Its main plot, provided by a specimen dream, reveals Freud's working through of the personal and professional conflicts of his life up to 1901, and serves as a practical demonstration of and paradigm for the process of working through in psychoanalysis. PMID:10824322

  14. Position-specific behaviors and their impact on crew performance: Implications for training

    NASA Technical Reports Server (NTRS)

    Law, J. Randolph

    1993-01-01

    The present study was motivated by results from a preliminary report documenting the impact of specific crewmembers on overall crew performance (Wilhelm & Law, 1992), and a cross-airline cross-fleet project investigating human factors behaviors of commercial aviation flightcrews (Helmreich, Butler, Whilhelm, & Lofaro, 1992). The purpose of the current investigation is to study how position-specific behaviors impact flightcrew performance, and how these position-specific behaviors differ between two airlines and two flying environments. Implications for training will also be addressed.

  15. [In Process Citation].

    PubMed

    Granada, Miguel A; Lenke, Nils; Roudet, Nicolas

    2014-01-01

    We report on a newly discovered letter by Christoph Rothmann, dated July 1st 1584, and addressed to Johann Ernst of Anhalt. The letter supports the earlier assumption that Johann Ernst recommended Rothmann to Landgrave Wilhelm of Hesse, as Rothmann asks for Johann Ernst's help on the matter in this new source. More importantly Rothmann refers to his attempts to make Copernicus' calculations compatible with the Ptolomean model, which demonstrates that already at this stage of his career he was working on such a compromise, and not only after being influenced by Raimarus Ursus or Tycho Brahe, as has been argued by some authors. PMID:25942771

  16. Astro-Dynasty

    NASA Astrophysics Data System (ADS)

    Belkora, Leila

    2001-05-01

    Four generations of Struves directed eight observatories over two centuries. The first, Wilhelm Struve moved to Estonia from northern Germany to escape Napoleon's military conscription. He pursued university studies and ended up running an observatory for 20 years. Raising his family at the observatory in isolated conditions encouraged his offspring to follow his career path. The last, Otto Struve, was the first director of McDonald Observatory. The Struves were winners of several Gold Medals from Britain's Royal Astronomical Society for their research.

  17. The eROSITA All-Sky Survey and its spectroscopic follow-up

    NASA Astrophysics Data System (ADS)

    Salvato, Mara

    2015-08-01

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian/German Spektrum-Roentgen-Gamma (SRG) mission which is current scheduled for launch in 2016. In the soft band (0.5-2 keV), the deep All-sky survey will be 30 times more sensitive than the previous ROSAT All-sky survey, while the first ever true all-sky survey will be mapped in the hard band (2-8 keV).The design driving science is the detection of large samples of galaxy clusters to redshifts z > 1, in order to study the large scale structure in the Universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of around 3 million active galactic nuclei, which is bound to revolutionize our view of the evolution of supermassive black holes and their impact on the process of structure formation in the Universe.I will review the main characteristics of eROSITA All-sky survey, with an eye also on the planned spectroscopic follow-up of the sources with SDSS-IV/SPIDERS and ESO/4MOST.

  18. eROSITA - Mapping the X-ray universe

    NASA Astrophysics Data System (ADS)

    Predehl, P.

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian/German Spektrum-Roentgen-Gamma (SRG) mission which is currently scheduled for launch late 2015/early 2016. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5-2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters to redshifts {z > 1} in order to study the large scale structure in the universe and test cosmological models including dark energy. In addition, eROSITA is expected to yield a sample of a few million active galactic nuclei, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including X-ray binaries, active stars, and diffuse emission within the Galaxy. eROSITA is currently (Jan 2014) in its flight model and calibration phase. All seven flight mirror modules (plus one spare) have been delivered and measured in X-rays. The first camera including the complete electronics has been extensively tested. So far, all subsystems and components are well within the expected performance.

  19. eROSITA

    NASA Astrophysics Data System (ADS)

    Predehl, Peter; Nandra, Kirpal; eRosita Collaboration

    2012-09-01

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian Spektrum-Roentgen-Gamma (SRG) mission which is current scheduled for launch in 2014. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5-2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters to redshifts z > 1 in order to study the large scale structure in the Universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of around 3 million AGN, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including X-ray binaries, active stars and diffuse emission within the Galaxy.

  20. Tolerance data of Gd-DTPA: a review.

    PubMed

    Niendorf, H P; Dinger, J C; Haustein, J; Cornelius, I; Alhassan, A; Clauss, W

    1991-01-01

    Gd-DTPA is the first paramagnetic contrast agent approved for clinical use in cranial and spinal MRI in the F.R.G., U.S.A., Japan and several other countries. After submission 13,439 patients were enrolled in standardized protocolled clinical trials. The observed adverse drug reactions (ADRs) after i.v. injection of Gd-DTPA were comparable to those after administration of iodinated non-ionic roentgen contrast media (CM). However, the overall incidence of ADRs after intravenous injection of 0.1 or 0.2 mmol/kg body weight Gd-DTPA was found to be even lower. Adverse events were observed in only 1.46% of the patients - or 1.14% if localized warmth is excluded. None of them was critical. There was no correlation between patient age and the incidence of ADRs. In patients with a known history of allergy the incidence of ADRs was increased by a factor 3-4, which is still lower than the incidence reported after intravenous administration of iodinated non-ionic roentgen CM to patients without known allergy. Good renal tolerance was seen in all patients, irrespective of pre-existing renal impairment. Fast bolus injections of Gd-DTPA were tolerated without added risk. The favorable safety profile is also reflected in the post marketing surveillance reports since Gd-DTPA became available as a commercial drug. PMID:1889423

  1. The correlation between immediate radiolucent lines and early implant migration in cemented acetabular components.

    PubMed

    Kneif, Damaris; Downing, Martin Richard; Ashcroft, George Patrick; Knight, David J; Ledingham, William M; Gibson, Peter H; Hutchison, James D

    2006-02-01

    Periacetabular radiolucent lines (RLLs) on postoperative radiographs have been associated with early loosening of the acetabular component. It has also been shown that excessive migration of an implant corresponds to an increased incidence of later clinical failure. This study relates RLLs on anterior-posterior hip radiographs taken 10 days and 6 months postoperatively to implant migration detected by roentgen stereophotogrammetric analysis. We have shown that RLLs in DeLee and Charnley zone III in the first week postoperatively as well as at 6 months are positively and significantly (P < .05) associated with migration detected by roentgen stereophotogrammetric analysis. No significant association was found for zone I or II at either 10 days or at 6 months. Considering the limitations in observing RLLs, their presence in zone III appears to reflect on the mechanical stability of the acetabular cup from the beginning. This indicates that zone III, which represents the inferomedial aspect of the acetabulum, might have to receive special attention when preparing the acetabulum and implanting the acetabular cup. PMID:16520209

  2. A constrained acetabular component for recurrent dislocation.

    PubMed

    Khan, R J K; Fick, D; Alakeson, R; Haebich, S; de Cruz, M; Nivbrant, B; Wood, D

    2006-07-01

    We treated 34 patients with recurrent dislocation of the hip with a constrained acetabular component. Roentgen stereophotogrammetric analysis was performed to assess migration of the prosthesis. The mean clinical follow-up was 3.0 years (2.2 to 4.8) and the radiological follow-up was 2.7 years (2.0 to 4.8). At the latest review six patients had died and none was lost to follow-up. There were four acetabular revisions, three for aseptic loosening and one for deep infection. Another acetabular component was radiologically loose with progressive radiolucent lines in all Gruen zones and was awaiting revision. The overall rate of aseptic loosening was 11.8% (4 of 34). Roentgen stereophotogrammetric analysis in the non-revised components confirmed migration of up to 1.06 mm of translation and 2.32 degrees of rotation at 24 months. There was one case of dislocation and dissociation of the component in the same patient. Of the 34 patients, 33 (97.1%) had no further episodes of dislocation. The constrained acetabular component reported in our study was effective in all but one patient with instability of the hip, but the rate of aseptic loosening was higher than has been reported previously and requires further investigation. PMID:16798987

  3. eROSITA: Status and Scientific Prospects

    NASA Astrophysics Data System (ADS)

    Becker, Werner; eROSITA Team

    2016-06-01

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian Spektrum-Roentgen-Gamma (SRG) mission which is currently scheduled for launch in 2017. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5-2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters to redshifts z > 1 in order to study thelarge scale structure in the Universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of a few million AGN, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including neutron stars and pulsars, X-ray binaries, activestars and diffuse emission from supernova remnants. The talk reports on the status of eROSITA and its scientific prospects.

  4. eROSITA on SRG

    SciTech Connect

    Predehl, Peter; Boehringer, Hans; Brunner, Hermann; Brusa, Marcella; Burwitz, Vadim; Cappelluti, Nico; Dennerl, Konrad; Freyberg, Michael; Friedrich, Peter; Meidinger, Norbert; Muehlegger, Martin; Strueder, Lothar; Churazov, Evgeniy; Sunyaev, Rashid; Hasinger, Guenther; Kendziorra, Eckhard; Kreykenbohm, Ingo; Schmid, Christian; Santangelo, Andrea; Tenzer, Chris

    2010-07-15

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian Spektrum-Roentgen-Gamma (SRG) mission which is scheduled for launch in late 2012. eROSITA is fully approved and funded by the German Space Agency DLR and the Max-Planck-Society.The design driving science is the detection of 50-100 thousands Clusters of Galaxies up to redshift z{approx}1.3 in order to study the large scale structure in the Universe and test cosmological models, especially Dark Energy. This will be accomplished by an all-sky survey lasting for four years plus a phase of pointed observations. eROSITA consists of seven Wolter-I telescope modules, each equipped with 54 Wolter-I shells having an outer diameter of 360 mm. This would provide and effective area at 1.5 keV of {approx}1500 cm{sup 2} and an on axis PSF HEW of 15'' which would provide an effective angular resolution of 25''-30''. In the focus of each mirror module, a fast frame-store pn-CCD will provide a field of view of 1 deg. in diameter for an active FOV of {approx}0.83 deg{sup 2}. At the time of writing the instrument development is currently in phase C/D.

  5. Cost accounting of radiological examinations. Cost analysis of radiological examinations of intermediate referral hospitals and general practice.

    PubMed

    Lääperi, A L

    1996-01-01

    The purpose of this study was to analyse the cost structure of radiological procedures in the intermediary referral hospitals and general practice and to develop a cost accounting system for radiological examinations that takes into consideration all relevant cost factors and is suitable for management of radiology departments and regional planning of radiological resources. The material comprised 174,560 basic radiological examinations performed in 1991 at 5 intermediate referral hospitals and 13 public health centres in the Pirkanmaa Hospital District in Finland. All radiological departments in the hospitals were managed by a specialist in radiology. The radiology departments at the public health care centres operated on a self-referral basis by general practitioners. The data were extracted from examination lists, inventories and balance sheets; parts of the data were estimated or calculated. The radiological examinations were compiled according to the type of examination and equipment used: conventional, contrast medium, ultrasound, mammography and roentgen examinations with mobile equipment. The majority of the examinations (87%) comprised conventional radiography. For cost analysis the cost items were grouped into 5 cost factors: personnel, equipment, material, real estate and administration costs. The depreciation time used was 10 years for roentgen equipment, 5 years for ultrasound equipment and 5 to 10 years for other capital goods. An annual interest rate of 10% was applied. Standard average values based on a sample at 2 hospitals were used for the examination-specific radiologist time, radiographer time and material costs. Four cost accounting versions with varying allocation of the major cost items were designed. Two-way analysis of variance of the effect of different allocation methods on the costs and cost structure of the examination groups was performed. On the basis of the cost analysis a cost accounting program containing both monetary and nonmonetary variables was developed. In it the radiologist, radiographer and examination-specific equipment costs were allocated to the examinations applying estimated cost equivalents. Some minor cost items were replaced by a general cost factor (GCF). The program is suitable for internal cost accounting of radiological departments as well as regional planning. If more accurate cost information is required, cost assignment employing the actual consumption of the resources and applying the principles of activity-based cost accounting is recommended. As an application of the cost accounting formula the average costs of the radiological examinations were calculated. In conventional radiography the average proportion of the cost factors in the total material was: personnel costs 43%, equipment costs 26%, material costs 7%, real estate costs 11%, administration and overheads 14%. The average total costs including radiologist costs in the hospitals were (FIM): conventional roentgen examinations 188, contrast medium examinations 695, ultrasound 296, mammography 315, roentgen examinations with mobile equipment 1578. The average total costs without radiologist costs in the public health centres were (FIM): conventional roentgen examinations 107, contrast medium examinations 988, ultrasound 203, mammography 557. The average currency rate of exchange in 1991 was USD 1 = FIM 4.046. The following formula is proposed for calculating the cost of a radiological examination (or a group of examinations) performed with a certain piece of equipment during a period of time (e.g. 1 year): a2/ sigma ax*ax+ b2/ sigma bx*bx+ d1/d5*dx+ e1 + [(c1+ c2) + d4 + (e2 - e3) + f5 + g1+ g2+ i]/n. PMID:8804226

  6. Structure and Dynamics of the Quiet Solar Chromosphere

    NASA Technical Reports Server (NTRS)

    Kalkofen, Wolfgang; Wagner, William (Technical Monitor)

    2003-01-01

    For the meeting of the AAS/SPD in Albuquerque, NM, I organized a Topical Session of the AAS on Structure and Dynamics of Chromospheres. The grant support was used to bring to the US two of the speakers from abroad. I had invited them for presentations at the Session: Dr. Klaus Wilhelm, the former PI of the SUMER instrument on SOHO, from the Max-Planck Institut in Lindau, Germany, and Dr. Sirajul Hasan, from the Indian Institute of Astrophysics in Bangalore, India. Both speakers preceded their trip to the AAS meeting with a stay at the Smithsonian Astrophysical Observatory, where they interacted with members of the Solar and Stellar Physics division. The highlights of the visits were the talks at the AAS/SPD meeting, in which six invited speakers told the audience of astronomers about current problems in solar physics and their relation to stellar problems. An important result of the visits is a paper by Dr. Wilhelm and me on 'Observations of the upper solar chromosphere with SUMER on SOHO', which has been submitted to Astronomy and Astrophysics for publication.

  7. The place of the 17th century in Jung's encounter with China.

    PubMed

    Cambray, Joe

    2005-04-01

    After recounting several dreams and related alchemical interests of Jung's tied to the 17(th) century, a contextualizing look at select scientific and philosophical developments of that century is presented. Several precursors of the contemporary debates on the mind/body relation are noted, with special reference to the work of Antonio Damasio. This in turn leads to a reconsideration of the work of the 17(th) century polymath Gottfried Wilhelm Leibniz, which Jung read as a major precursor to his formulation of synchronicity (via Leibniz's concept of 'pre-established harmony'). Leibniz was the first philosopher to articulate the mind/body relationship in terms of supervenience, sharing an accord with those contemporary philosophers and scientists who see the mind as being an emergent property of the body-brain. Similarly, these ideas are also consistent with a reformulation of synchronicity in terms of emergence. Tracing Leibniz's interest in China reveals another set of links to Jung and to emergentism. Jung's use of Taoist concepts in developing the synchronicity principle is well known. According to scholars, Leibniz was the first major Western intellect to study the I-Ching, through the assistance of a Jesuit missionary in Beijing, Fr. Joachim Bouvet. Some details of the Leibniz-Bouvet correspondence are discussed here. Despite Helmut Wilhelm's presenting aspects of this correspondence at an Eranos conference, Jung does not appear to have integrated it into his writing on synchronicity--a possible reason for this omission is suggested. PMID:15817042

  8. Understanding and Explanation in France: From Maine de Biran's Méthode Psychologique to Durkheim's Les Formes Élémentaires de la vie Religieuse

    NASA Astrophysics Data System (ADS)

    Schmaus, Warren

    My task here is to compare the ways in which the relations between the human and the natural sciences were conceived in late nineteenth and early twentieth century France and Germany. Historical generalization may be a mug's game. But if I had to generalize, I would say that the French distinguished the human or cultural sciences from the natural sciences only in terms of their subject matters, while the Germans were more likely to try to distinguish them in terms of their goals, methods, foundations, and normative content as well. Although we may be able to find many philosophical positions among the French that resemble certain aspects of the thought of Wilhelm Dilthey, Wilhelm Windelband, or Heinrich Rickert, no one in France held exactly the same combination of philosophical views concerning the human sciences as that held by any of these German thinkers. In particular, no one in France tried to distinguish the human from the natural sciences in terms of understanding versus explanation in the way that Dilthey did. Thus, although there were other disputes in France in regard to the human sciences, such as that between Émile Durkheim and Gabriel Tarde over the role of psychology in sociological explanation, or that between sociologists and philosophers over the methods of ethics, there was no controversy analogous to the conflict among Dilthey, Windelband, and Rickert over the best way to distinguish the human from the natural sciences.

  9. Dilemmas of 19th-century Liberalism among German Academic Chemists: Shaping a National Science Policy from Hofmann to Fischer, 1865-1919.

    PubMed

    Johnson, Jeffrey Allan

    2015-04-01

    This paper's primary goal is to compare the personalities, values, and influence of August Wilhelm Hofmann and Emil Fischer as exemplars and acknowledged leaders of successive generations of the German chemical profession and as scientists sharing a 19th-century liberal, internationalist outlook from the German wars of unification in the 1860s to Fischer's death in 1919 in the aftermath of German defeat in World War I. The paper will consider the influence of Hofmann and Fischer on the shaping of national scientific institutions in Germany, from founding of the German Chemical Society in 1867 to the first institutes of the Kaiser Wilhelm Society founded in 1911, their academic leadership in other areas including the shaping of a successful academic-industrial symbiosis in organic chemistry, and finally their response to war as a force disruptive of scientific internationalism. All of these developments posed serious dilemmas, exacerbated by emerging strains of nationalism and anti-Semitism in German society. Whereas Hofmann's lifework came to a relatively successful end in 1892, Fischer was not so fortunate, as the war brought him heavy responsibilities and terrible personal losses, but with no German victory and no peace of reconciliation--a bleak end for Fischer and the 19th-century liberal ideals that had inspired him. PMID:26104166

  10. A Diversity of Divisions: Tracing the History of the Demarcation between the Sciences and the Humanities.

    PubMed

    Bouterse, Jeroen; Karstens, Bart

    2015-06-01

    Throughout history, divides between the sciences and the humanities have been drawn in many different ways. This essay shows that the notion of a divide became more urgent and pronounced in the second half of the nineteenth century. While this shift has several causes, the essay focuses on the rise of the social sciences, which is interpreted as posing a profound challenge to the established disciplines of the study of humankind. This is demonstrated by zooming in on linguistics, one of the key traditional disciplines of the humanities. Through the assumption of a correspondence between mental and linguistic categories, psychology became of central importance in the various conceptions of linguistics that emerged in the nineteenth century. Both linguistics and psychology were very much engaged in a process of discipline formation, and opinions about the proper directions of the fields varied considerably. Debates on these issues catalyzed the construction of more radical divisions between the sciences and the humanities. Both Wilhelm Dilthey's dichotomy between understanding and explanation and Wilhelm Windelband's dichotomy between nomothetic and idiographic sciences respond to these debates. While their constructions are often lumped together, the essay shows that they actually meant very different things and have to be treated accordingly. PMID:26353439

  11. Corrosion behavior of nodular cast iron casks for low and intermediate level wastes

    SciTech Connect

    Hauser, W.; Koester, R.

    1986-01-01

    In applying new conditioning methods dehydrated wastes (e.g. concentrates, ion exchange resins) from operation of nuclear power plants and wastes from decommissioning (e.g., highly-activated core components) are conditioned using high integrity nodular cast iron casks without further solidification. Therefore more stringent requirements have to be made for the packaging material. The objective of the investigations was to evaluate the corrosion resistance of the cask material. For this purpose chemical corrosion tests were made applying corrosion media actually considered or postulated in accident scenarios during interim storage or after disposal in the abandoned iron ore mine Konrad or in a salt formation. The conclusion from the corrosion experiments, which have been performed up to now for the basic packaging material, indicates that nodular cast iron casks with wall thicknesses about 200 mm seem to ensure good protection for wastes especially from nuclear power plants with relatively short-lived radionuclides.

  12. Public and political issues in radioactive waste management in the Federal Republic of Germany

    SciTech Connect

    Neis, A.

    1993-12-31

    The Federal Government`s radioactive waste management concept and regulations governing formal public participation in licensing procedures for radioactive waste management facilities are presented. The paper focuses on public and political issues arising from widely diverging views in different social groups on nuclear energy and on radioactive waste management. The resulting conflict between Federal and Laender (Federal constituent states) authorities and the actual course of public participation in a licensing procedure are illustrated with the example of planned final disposal of radioactive waste in the Konrad mine. Major national efforts to overcome the unsatisfying present situation are presented and the role of international consensus is briefly touched. Concluding remarks will particularly justify admissibility and emphasize the need to discuss and eventually decide on radioactive waste management issues regardless of diverging views on nuclear energy.

  13. Baby schema modulates the brain reward system in nulliparous women

    PubMed Central

    Glocker, Melanie L.; Langleben, Daniel D.; Ruparel, Kosha; Loughead, James W.; Valdez, Jeffrey N.; Griffin, Mark D.; Sachser, Norbert; Gur, Ruben C.

    2009-01-01

    Ethologist Konrad Lorenz defined the baby schema (“Kindchenschema”) as a set of infantile physical features, such as round face and big eyes, that is perceived as cute and motivates caretaking behavior in the human, with the evolutionary function of enhancing offspring survival. The neural basis of this fundamental altruistic instinct is not well understood. Prior studies reported a pattern of brain response to pictures of children, but did not dissociate the brain response to baby schema from the response to children. Using functional magnetic resonance imaging and controlled manipulation of the baby schema in infant faces, we found that baby schema activates the nucleus accumbens, a key structure of the mesocorticolimbic system mediating reward processing and appetitive motivation, in nulliparous women. Our findings suggest that engagement of the mesocorticolimbic system is the neurophysiologic mechanism by which baby schema promotes human caregiving, regardless of kinship. PMID:19451625

  14. Heritage Gallery

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Marshall Space Flight Center's (MSFC's) building 4200 hosts a new spaceflight history museum referred to as the Heritage Gallery, allowing employees and visitors alike to have the opportunity to experience history first hand. On display are many models of launch vehicles and spacecraft that have made the center famous. It features a full-scale mockup of the lunar roving vehicle, three built-in multimedia displays, a large theater screen, and two glass cases that house memorabilia such as personal items belonging to Wernher von Braun, MSFC's first Center Director. The new Heritage Gallery features the accomplishments of several past and present members of the Marshall team. Attending the ribbon cutting ceremony are: (left to right) Gerhard Reisig; Cort Durocher, executive director of the American Institute of Aeronautics and Astronautics; Ernst Stuhlinger; Konrad Darnenburg; Werner Dahm; Walter Jacobi; and host of event, Center Director Art Stephenson.

  15. Freud, his illness, and ourselves.

    PubMed

    Haynal, Andr

    2008-06-01

    The history of Freud's illness shows that he tried to avoid confrontation with it, and to treat it as unimportant. In his personal letters, the ill body remains outside-as another person, "Konrad," not he himself-and it is not taken into account. Particularly in Freud's correspondence with Ferenczi, we realize to what extent certain phenomena, especially depressive ones, he considered somatic, with a tendency to dismiss them, and this despite important occasional insights, such as about the role played by hate in psychosomatic illnesses. In the post-Freudian development, these topics have been more and more integrated in the dialogue, in the discourse between the analyst and the analysand. PMID:18509365

  16. Darwin as a student of behavior.

    PubMed

    Thierry, Bernard

    2010-02-01

    In The Expression of the Emotions, Charles Darwin documents evolutionary continuity between animals and humans, emphasizing the universality of expressions in man. Most of the book addresses human behavior, and its influence on the study of animal behavior has been weak. The issue of natural selection is remarkably absent from this book, which relies on the inheritance of acquired characters rather than on a genuine Darwinian logic. Yet Konrad Lorenz considered Darwin to be a forerunner of behavioral biology. The reason was to be found in The Descent of Man and chapter VIII of The Origin of Species, where Darwin provides an explanation of behavior through selection, stating that the same mechanisms explaining morphological changes also account for gradual improvements in instincts. He assessed the accuracy of his evolutionary theory by directly studying animal behavior, hence laying the foundations of behavioral research for the next century. PMID:20338536

  17. The evolution of Harry Harlow: from the nature to the nurture of love.

    PubMed

    Vicedo, Marga

    2010-06-01

    Harlow deserves a place in the early history of evolutionary psychiatry but not, as he is commonly presented, because of his belief in the instinctual nature of the mother-infant dyad. Harlow's work on the significance of peer relationships led him to appreciate the evolutionary significance of separate affectional systems. Over time, Harlow distanced himself from the ideas of John Bowlby and Mary Ainsworth as well as from Konrad Lorenz's views about imprinting and instincts. Harlow's work did not lend support to Bowlby's belief in an innate need for mother love and his thesis that the mother was the child's psychic organizer. Nor did Harlow agree with Lorenz's view of instincts as biological, unmodifiable innate needs, unaffected by learning. PMID:21877372

  18. Baby schema modulates the brain reward system in nulliparous women.

    PubMed

    Glocker, Melanie L; Langleben, Daniel D; Ruparel, Kosha; Loughead, James W; Valdez, Jeffrey N; Griffin, Mark D; Sachser, Norbert; Gur, Ruben C

    2009-06-01

    Ethologist Konrad Lorenz defined the baby schema ("Kindchenschema") as a set of infantile physical features, such as round face and big eyes, that is perceived as cute and motivates caretaking behavior in the human, with the evolutionary function of enhancing offspring survival. The neural basis of this fundamental altruistic instinct is not well understood. Prior studies reported a pattern of brain response to pictures of children, but did not dissociate the brain response to baby schema from the response to children. Using functional magnetic resonance imaging and controlled manipulation of the baby schema in infant faces, we found that baby schema activates the nucleus accumbens, a key structure of the mesocorticolimbic system mediating reward processing and appetitive motivation, in nulliparous women. Our findings suggest that engagement of the mesocorticolimbic system is the neurophysiologic mechanism by which baby schema promotes human caregiving, regardless of kinship. PMID:19451625

  19. LL/ILW: Post-Qualification of Old Waste through Non-Destructive Extraction of Barrels from Cement Shields - 13535

    SciTech Connect

    Oehmigen, Steffen; Ambos, Frank

    2013-07-01

    Currently there is a large number of radioactive waste drums entombed in cement shields at German nuclear power plants. These concrete containers used in the past for the waste are not approved for the final repository. Compliance with current acceptance criteria of the final repository has to be proven by qualification measures on the waste. To meet these criteria, a new declaration and new packing is necessary. A simple non-destructive extraction of about 2000 drums from their concrete shields is not possible. So different methods were tested to find a way of non-destructive extraction of old waste drums from cement shields and therefore reduce the final repository volume and final repository costs by using a container accepted and approved for Konrad. The main objective was to build a mobile system to offer this service to nuclear plant stations. (authors)

  20. A century of endodontics: from Philadelphia to Boston.

    PubMed

    Millstein, Charles B

    2010-01-01

    While Dr. Grossman was in Rostock with a letter of introduction from Dr. Prinz, he visited several distinguished dentists in Berlin. One was the aged Dr. Otto Walkoff, who, with the help of a physicist while in Wurzberg, was the first dentist to capture the image of a tooth soon after the discovery of radiology by Roentgen in 1895. At his home, Dr. Walkoff passed the X-ray tube head that had taken the historic film to Dr. Grossman, who then held this treasured artifact in his hands. This transfer of culture from Germany to the United States marked the beginning of modern endodontics. Similarly, when Dr. Goldman gave Dr. Schilder his backing by sending him to study under Dr. Grossman at the University of Pennsylvania, the progress of endodontic excellence moved forward, ensuring a Century of Endodontics. PMID:20806701

  1. X-Ray Phase-Contrast Imaging with Three 2D Gratings

    PubMed Central

    Jiang, Ming; Wyatt, Christopher Lee; Wang, Ge

    2008-01-01

    X-ray imaging is of paramount importance for clinical and preclinical imaging but it is fundamentally restricted by the attenuation-based contrast mechanism, which has remained essentially the same since Roentgen's discovery a century ago. Recently, based on the Talbot effect, groundbreaking work was reported using 1D gratings for X-ray phase-contrast imaging with a hospital-grade X-ray tube instead of a synchrotron or microfocused source. In this paper, we report an extension using 2D gratings that reduces the imaging time and increases the accuracy and robustness of phase retrieval compared to current grating-based phase-contrast techniques. Feasibility is demonstrated via numerical simulation. PMID:18401460

  2. FORMATION BY IRRADIATION OF AN EXPANDED, CELLULAR, POLYMERIC BODY

    DOEpatents

    Charlesby, A.; Ross, M.

    1958-12-01

    The treatment of polymeric esters of methacrylic acid having a softening polnt above 40 icient laborato C to form an expanded cellular mass with a smooth skin is discussed. The disclosed method comprises the steps of subjecting the body at a temperature below the softenpoint to a dose of at least 5 x lO/sup 6/ roentgen of gamma radiation from cobalt-60 source until its average molecular weight is reduced to a value within the range of 3 x lO/sup 5/ to 10/sup 4/, and heating at a temperature within the range of 0 to lO icient laborato C above its softening point to effect expansion.

  3. ROSAT observations of z greater than 3 quasars

    NASA Technical Reports Server (NTRS)

    Pickering, T. E.; Impey, C. D.; Foltz, C. B.

    1994-01-01

    Successful pointed observations using the Roentgen Satellite (ROSAT) Position Sensitive Proportional Counter (PSPC) were made of seven z greater than 3 optically selected quasars from the Large Bright Quasar Survey (LBQS). Four detections and three 3 sigma upper limits resulted. Combining these data with the heterogeneous sample of Avni & Tananbaum (1986) confirms their conclusion that the ratio of x-ray to optical luminosity is correlated with optical luminosity and probably not correlated with redshift. This suggests that x-ray luminosity evolves more slowly than optical luminosity. These results are then used in conjunction with the LBQS database to estimate the contribution to the 2 keV x-ray background of bright, optically selected quasars with m(sub B(sub J)) less than 18.85; the result is about 5%.

  4. Bone mass determination from microradiographs by computer-assisted videodensitometry. II. Aluminium as a reference substance.

    PubMed

    Kälebo, P; Strid, K G

    1988-01-01

    Aluminium was evaluated as a reference substance in the assessment of rabbit cortical bone by microradiography followed by videodensitometry. Ten dense, cortical-bone specimens from the same tibia diaphysis were microradiographed using prefiltered 27 kV roentgen radiation together with aluminium step wedges and bone simulating phantoms for calibration. Optimally exposed and processed plates were analysed by previously described computer-assisted videodensitometry. For comparison, the specimens were analysed by physico-chemical methods. A strict proportionality was found between the 'aluminium equivalent mass' and the ash weight of the specimens. The total random error was low with a coefficient of variation within 1.5 per cent. It was concluded that aluminium is an appropriate reference material in the determination of cortical bone, which it resembles in effective atomic number and thus x-ray attenuation characteristics. The 'aluminium equivalent mass' is suitably established as the standard of expressing the results of bone assessment by microradiography. PMID:3166886

  5. Postirradiation sarcoma (malignant fibrous histiocytoma) in the inguinal region.

    PubMed

    Tanaka, T; Miwa, H; Orita, K; Hiraki, Y; Yamamoto, M; Hashimoto, K; Yumoto, T

    1982-01-01

    A female patient who died of apparent postirradiation sarcoma at the age of 39 was reported. Following a traffic accident, she developed squamous cell carcinoma at the injured right heel 20 years later, and also metastasis to both inguinal and popliteal lymph nodes. During the period from September 1966 to May 1968, she had received Co60 irradiation to the right inguinal and para-aortic areas, 9,600 and 6,600 Roentgen, respectively. Ten years later, she manifested a huge tumor in the inguinal region which extended further to the retroperitoneum; light and electron microscopic examinations proved to be a malignant fibrous histiocytoma. She died of massive pulmonary metastasis two years later. Histological differentiation of the tumor and relationship between irradiation and sarcoma induction were briefly discussed, and the necessity of reevalution of soft part sarcomas was emphasized. PMID:6280439

  6. Research and technology, 1990: Goddard Space Flight Center

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Goddard celebrates 1990 as a banner year in space based astronomy. From above the Earth's obscuring atmosphere, four major orbiting observatories examined the heavens at wavelengths that spanned the electromagnetic spectrum. In the infrared and microwave, the Cosmic Background Explorer (COBE), measured the spectrum and angular distribution of the cosmic background radiation to extraordinary precision. In the optical and UV, the Hubble Space Telescope has returned spectacular high resolution images and spectra of a wealth of astronomical objects. The Goddard High Resolution Spectrograph has resolved dozens of UV spectral lines which are as yet unidentified because they have never before been seen in any astronomical spectrum. In x rays, the Roentgen Satellite has begun returning equally spectacular images of high energy objects within our own and other galaxies.

  7. The evolution of the quasar continuum

    NASA Technical Reports Server (NTRS)

    Elvis, M.

    1992-01-01

    We now have in hand a large data base of Roentgen Satellite (ROSAT), optical, and IR complementary data. We are in the process of obtaining a large amount of the International Ultraviolet Explorer (IUE) data for the same quasar sample. For our complementary sample at high redshifts, where the UV was redshifted into the optical, we have just had approved large amounts of observing time to cover the quasar continuum in the near-IR using the new Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) array spectrographs. Ten micron, optical, and VLA radio, data also have approved time. An ISO US key program was approved to extend this work into the far-IR, and the launch of ASTRO-D (early in 1993) promises to extend it to higher energy X-rays.

  8. Spinal X-ray screening of high performance fighter pilots.

    PubMed

    Andersen, H T; Wagstaff, A S; Sverdrup, H U

    1991-12-01

    Neck pain and neck injury are common complaints among military aviators flying high performance (HPF) aircraft. Since all candidates for military flying training with the Royal Norwegian Air Force have to meet HPF medical standards, medical selection procedures include a radiological examination of the spine. Nine films of the vertebral column are made with emphasis put on cervical structures. Among 232 applicants, 527 deviations from normal conditions were described--anomalies, degenerative changes and deviations of posture--which average 2.27 diagnoses per spine X-rayed. Of the candidates, 80 were considered entirely within normal limits; 20 were rejected due to the roentgen findings; and five candidates were excluded on final evaluation, their radiological diagnoses contributing to the decision. Although most changes are slight, many significant conditions are demonstrated among young healthy individuals. Since the population is highly selected, the figures we present may be minimum numbers in a western industralized society. PMID:1755799

  9. An aerial radiological survey of the project Rio Blanco and surrounding area

    SciTech Connect

    Singman, L.V.

    1994-11-01

    A team from the Remote Sensing Laboratory in Las Vegas, Nevada, conducted an aerial radiation survey of the area surrounding ground zero of Project Rio Blanco in the northwestern section of Colorado in June 1993. The object of the survey was to determine if there were man-made radioisotopes on or near the surface resulting from a nuclear explosion in 1972. No indications of surface contamination were found. A search for the cesium-137 radioisotope was negative. The Minimum Detectable Activity for cesium-137 is presented for several detection probabilities. The natural terrestrial exposure rates in units of Roentgens per hour were mapped and are presented in the form of a contour map over-laid on an aerial photograph. A second team made independent ground-based measurements in four places within the survey area. The average agreement of the ground-based with aerial measurements was six percent.

  10. New horizons for study of the cardiopulmonary and circulatory systems. [image reconstruction techniques

    NASA Technical Reports Server (NTRS)

    Wood, E. H.

    1976-01-01

    The paper discusses the development of computer-controlled three-dimensional reconstruction techniques designed to determine the dynamic changes in the true shape and dimensions of the epi- and endocardial surfaces of the heart, along with variable time base (stop-action to real-time) displays of the transmural distribution of the coronary microcirculation and the three-dimensional anatomy of the macrovasculature in all regions of the body throughout individual cardiac and/or respiratory cycles. A technique for reconstructing a cross section of the heart from multiplanar videoroentgenograms is outlined. The capability of high spatial and high temporal resolution scanning videodensitometry makes possible measurement of the appearance, mean transit and clearance of roentgen opaque substances in three-dimensional space through the myocardium with a degree of simultaneous anatomic and temporal resolution not obtainable by current isotope techniques. The distribution of a variety of selected chemical elements or biologic materials within a body portion can also be determined.

  11. X-ray emission from the historical supernovae in the spiral galaxy NGC 6946: SN 1980K and SN 1968D recovered ?

    NASA Technical Reports Server (NTRS)

    Schlegel, Eric M.

    1994-01-01

    This paper describes a study of the Roentgen Satellite (ROSAT) Position Sensitive Proportional Counter (PSPC) observation of the spiral galaxy NGC 6946 to search for x-ray emission from the six historical supernovae that have occurred in that galaxy. At the age of these supernovae, all could be emitting x rays due to circumstellar interactions. Supernova (SN) 1980K may be present based upon the hardness ratio and the coincidence of an x-ray source with the optical position. Its luminosity agrees with a recent prediction by Chevalier & Fransson. The situation for SN 1968D, apparently recovered in Very Large Array (VLA) data, is less clear due to source confusion, but suggests SN 1968D has not been recovered. Only upper limits are available for the remaining four supernovae that have occurred in this galaxy.

  12. Relevant signs of stable and unstable thoracolumbar vertebral column trauma

    SciTech Connect

    Gehweiler, J.A.; Daffner, R.H.; Osborne, R.L.

    1981-12-01

    One-hundred and seventeen patients with acute thoracolumbar vertebral column fracture or fracture-dislocations were analyzed and classified into stable (36%) and unstable (64%). Eight helpful roentgen signs were observed that may serve to direct attention to serious underlying, often occult, fractures and dislocations. The changes fall into four principal groups: abnormal soft tissues, abnormal vertebral alignment, abnormal joints, and widened vertebral canal. All stable and unstable lesions showed abnormal soft tissues, while 70% demonstrated kyphosis and/or scoliosis, and an abnormal adjacent intervertebral disk space. All unstable lesions showed one or more of the following signs: displaced vertebra, widened interspinous space, abnormal apophyseal joint(s), and widened vertebral canal.

  13. Large pleural effusion necessitates chest tube drainage in a patient with Kawasaki disease.

    PubMed

    Yavuz, Taner; Nisli, Kemal; Yilmaz, Ceren; Dindar, Aygun

    2007-03-01

    An 11-month-old Turkish boy was hospitalised with clinical and roentgen graphic evidence of large pleural effusion on the third day of fever and misdiagnosed as parapneumonic effusion. Due to worsening respiratory distress chest tube drainage was performed. Four days later the classic signs of Kawasaki disease appeared. His clinical condition improved gradually and fever subsided after intravenous gammaglobulin and aspirin treatment. A mild transient dilatation of the right coronary artery was seen and returned to the normal diameter within a few weeks. To our knowledge, large pleural effusion in a case of Kawasaki disease, in which chest tube drainage was needed, has not been reported. We describe here a patient with complete Kawasaki disease whose initial presentation mimicked a parapneumonic effusion. PMID:17316197

  14. [A comparative assessment between transrectal echography, venous urography, CAT and morphology in patients with prostatic carcinoma].

    PubMed

    Mladenov, D; Tsvetkov, M; Topov, Ia; Kumanov, Kh

    1994-01-01

    By incidence rate prostate gland carcinoma ranks second among all neoplastic diseases. As all tumorous neoformations, it is conspicuous for its progressive character. Clinical, laboratory and roentgen methods, thus far routinely used in practice, are hardly in a position to establish correct and accurate diagnosis alone. The diagnostic potentials of transrectal ultrasound examination, intravenous urography, CAT and morphological patterns are comparatively studied in patients presenting prostate gland carcinoma. The obtained results point to a greater diagnostic relevance of transrectal ultrasound examination, by comparison with CAT and intravenous urography. It is a matter of a noninvasive and highly effective procedure for primary diagnosis of the neoplastic process. Emphasis is laid on the necessity to confirm the echographic diagnosis in all instances by performing morphological study in conjunction with the remaining diagnostic methods. PMID:7474720

  15. Lymphoid cell kinetics under continuous low dose-rate gamma irradiation: A comparison study

    NASA Technical Reports Server (NTRS)

    Foster, B. R.

    1975-01-01

    The mechanism of cell proliferation is studied in the lymphoid tissue of the mouse spleen under the stress of continuous irradiation at a dose-rate of 10 roentgens per day for 105 days. Autoradiography and specific labeling with tritiated thymidine were utilized. It was found that at least four compensatory mechanisms maintained a near-steady state of cellular growth: (1) an increase in the proportion of PAS-positive cells which stimulate mitotic activity, (2) maturation arrest of proliferating and differentiating cells which tend to replenish the cells damaged or destroyed by irradiation, (3) an increase in the proportion of cells proliferating, and (4) an increase in the proportion of precursor cells. The results are compared to previous findings observed in the thymus.

  16. Lymphoid cell kinetics under continuous low dose-rate gamma irradiation: A comparison study

    NASA Technical Reports Server (NTRS)

    Foster, B. R.

    1975-01-01

    A comparison study was conducted of the effects of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue (white pulp) of the mouse spleen with findings as they relate to the mouse thymus. Experimental techniques employed included autoradiography and specific labeling with tritiated thymidine (TdR-(h-3)). The problem studied involved the mechanism of cell proliferation of lymphoid tissue of the mouse spleen and thymus under the stress of continuous irradiation at a dose rate of 10 roentgens (R) per day for 105 days (15 weeks). The aim was to determine whether or not a steady state or near-steady state of cell population could be established for this period of time, and what compensatory mechanisms of cell population were involved.

  17. Biomedical technology transfer. Applications of NASA science and technology

    NASA Technical Reports Server (NTRS)

    Harrison, D. C.

    1980-01-01

    Ongoing projects described address: (1) intracranial pressure monitoring; (2) versatile portable speech prosthesis; (3) cardiovascular magnetic measurements; (4) improved EMG biotelemetry for pediatrics; (5) ultrasonic kidney stone disintegration; (6) pediatric roentgen densitometry; (7) X-ray spatial frequency multiplexing; (8) mechanical impedance determination of bone strength; (9) visual-to-tactile mobility aid for the blind; (10) Purkinje image eyetracker and stabilized photocoalqulator; (11) neurological applications of NASA-SRI eyetracker; (12) ICU synthesized speech alarm; (13) NANOPHOR: microelectrophoresis instrument; (14) WRISTCOM: tactile communication system for the deaf-blind; (15) medical applications of NASA liquid-circulating garments; and (16) hip prosthesis with biotelemetry. Potential transfer projects include a person-portable versatile speech prosthesis, a critical care transport sytem, a clinical information system for cardiology, a programmable biofeedback orthosis for scoliosis a pediatric long-bone reconstruction, and spinal immobilization apparatus.

  18. Initial performance parameters on FXR

    SciTech Connect

    Kulke, B.; Innes, T.G.; Kihara, R.; Scarpetti, R.D.

    1982-06-11

    Construction of the new flash x-ray induction LINAC (FXR) at Lawrence Livermore National Laboratory has been completed. Initial tuning of the machine has produced stable current pulses in excess of 2 kA at the design energy of 20 MeV, with an 80 ns FWHM pulse width, producing single-pulse radiation doses near 500 Roentgen at one meter from the target. The electronic spot size on the bremsstrahlung target is estimated at 3 to 5 mm. In this paper we will discuss the basic FXR design; running-in and tuning of the machine; emittance measurements; beam stability; switch gap synchronization; and measurements of the radiation dose and angular distribution.

  19. Recent performance improvements on FXR

    SciTech Connect

    Kulke, B.; Kihara, R.

    1983-01-01

    The FXR machine is a nominal 4-kA, 20-MeV, linear-induction, electron accelerator for flash radiography at LLNL. The machine met its baseline requirements in March 1982. Since then, the performance has been greatly improved. We have achieved stable and repeatable beam acceleration and transport, with over 80% transmission to the tungsten bremsstrahlung target located some 35 m downstream. For best stability, external-beam steering has been eliminated almost entirely. We regularly produce over 500 Roentgen at 1 m from the target (TLD measurement), with a radiographic spot size of 3 to 5 mm. Present efforts are directed towards the development of a 4-kA tune, working interactively with particle-field and beam transport code models. A remaining uncertainty is the possible onset of RF instabilities at the higher current levels.

  20. What can be Learned from X-Ray Spectroscopy Concerning Hot Gas in the Local Bubble and Charge Exchange Processes

    NASA Technical Reports Server (NTRS)

    Snowden, Steven L.

    2007-01-01

    Solar wind charge exchange produces diffuse X-ray emission with a variable surface brightness comparable to that of the cosmic background. While the temporal variation of the charge exchange emission allows some separation of the components, there remains a great deal of uncertainty as to the zero level of both. Because the production mechanisms of the two components are considerably different, their spectra would provide critical diagnostics to the understanding of both. However, current X-ray observatories are very limited in both spectral resolution and sensitivity in the critical soft X-ray (less than 1.0 keV) energy range. Non-dispersive high-resolution spectrometers, such as the calorimeter proposed for the Spectrum Roentgen Gamma mission, will be extremely useful in distinguishing the cascade emission of charge exchange from the spectra of thermal bremsstrahlung cosmic plasmas.

  1. A comparison of the 3D kinematic measurements obtained by single-plane 2D-3D image registration and RSA.

    PubMed

    Muhit, Abdullah A; Pickering, Mark R; Ward, Tom; Scarvell, Jennie M; Smith, Paul N

    2010-01-01

    3D computed tomography (CT) to single-plane 2D fluoroscopy registration is an emerging technology for many clinical applications such as kinematic analysis of human joints and image-guided surgery. However, previous registration approaches have suffered from the inaccuracy of determining precise motion parameters for out-of-plane movements. In this paper we compare kinematic measurements obtained by a new 2D-3D registration algorithm with measurements provided by the gold standard Roentgen Stereo Analysis (RSA). In particular, we are interested in the out-of-plane translation and rotations which are difficult to measure precisely using a single plane approach. Our experimental results show that the standard deviation of the error for out-of-plane translation is 0.42 mm which compares favourably to RSA. It is also evident that our approach produces very similar flexion/extension, abduction/adduction and external knee rotation angles when compared to RSA. PMID:21097358

  2. Research of nanocomposite structure of boron nitride at proton radiation

    NASA Astrophysics Data System (ADS)

    Borodin, Y. V.; Ermolaev, D. S.; Pak, V.; Zhang, K.

    2016-02-01

    Using roentgen diffraction and electron microscopy, the influence of nanosecond irradiation by ion beams of high energy on forming of self-organized nanoblocks in near surface's layers of boron nitride (BN) has been studied. It was shown that low temperature transitions from hexagonal to wrutz boron nitrides is associated with changes of shape and sizes of self-organized particles consisting the nanoblocks. We have calculated the parameters of nanoblocks using the meanings of interplane distances and properties of subreflexes orders. The collective shifting deformations of layers in nanoblocks provides phase transition under the screen and forming the set of nanotubes with escaping of five order axes of symmetry. It has been realized that pentagons and stars arranged in points of entrance of five order axis of symmetry are associated with peculiarity of self-organization of the spiral-cyclic structures.

  3. Development of Mirror Modules for the ART-XC Instrument

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; O'Dell, S. L.; Elsner, R.; Kilaru, K.; McCracken, J.; Pavlinsky, M.; Lapshov, I.

    2012-01-01

    The Marshall Space Flight Center (MSFC) is developing x-ray mirror modules for the ART -XC instrument on board the Spectrum-Roentgen-Gamma Mission under a Reimbursable Agreement between NASA and the Russian Space Research Institute (IKI.) ART-XC will consist of seven co-aligned x-ray mirror modules with seven corresponding CdTe focal plane detectors. Currently, four of the modules are being fabricated by the Marshall Space Flight Center (MSFC.) Each MSFC module provides an effective area of 65 cm2 at 8 keV, response out to 30 keV, and an angular resolution of 45 arcsec or better HPD. We will present a status of the ART x-ray module development at MSFC.

  4. Laboratory x-ray spectroscopy experiments in support of NASA`s x-ray satellite missions

    SciTech Connect

    Kahn, S. M., Columbia University

    1998-05-22

    With support from NASA, we are performing a series of laboratory astrophysics investigations designed to address fundamental uncertainties in basic atomic physics processes relevant to the interpretation of discrete X-ray spectra of cosmic plasmas. Moderate resolution spectra acquired by the ASCA Observatory already demonstrate the inadequacy of currently available spectral modelling codes for this wavelength band. With the upcoming launches of AXAF, XMM, ASTRO E, and Spektrum Roentgen-Gamma, the demand for significant advances in this field will increase dramatically. Our program is based on the exploitation of the Electron Beam Ion Trap facility at the Lawrence Livermore National Laboratory, and a unique set of spectrometers and experimental techiques specifically developed for this purpose. Recent experiments have been devoted to definitive measurements of line emissivities for iron L-shell ions in optically thin, collisional plasmas.

  5. Movement patterns of the C-stem femoral component: an RSA study of 33 primary total hip arthroplasties followed for two years.

    PubMed

    Sundberg, M; Besjakov, J; von Schewelow, T; Carlsson, A

    2005-10-01

    We used roentgen stereophotogrammetric analysis to follow 33 C-stem femoral components for two years after primary total hip arthroplasty. All components migrated distally and posteriorly within the cement mantle. The mean distal migration was 1.35 mm (sd 0.62) at two years and the mean posterior migration was 1.35 mm (sd 0.69) at two years. All the femoral components rotated into retroversion with a mean rotation at two years of 1.9 degrees (sd 1.1). For all other directions, the prosthesis was stable up to two years. Compared with other tapered prostheses, the distal migration of the C-stem is the same, but posterior rotation and posterior migration are greater. PMID:16189306

  6. Disc Height and Sagittal Alignment in Operated and Non-Operated Levels in the Lumbar Spine at Long-Term Follow-Up: A Case-Control Study

    PubMed Central

    Froholdt, Anne; Brox, Jens Ivar; Reikerås, Olav; Leivseth, Gunnar

    2013-01-01

    Purpose: To compare lumbar disc degeneration at 9-year follow-up in patients with chronic low back pain who had instrumented lumbar fusion or no fusion. Material and methodology: The main outcomes were disc height and sagittal alignment measured by Distortion Compensated Roentgen Analysis (DCRA). Secondary outcome included the Oswestry Disability Index and VAS back pain. Results: Forty-eight patients with baseline and 9-year radiographs from L2- S1 were included. Twenty-three had lumbar fusion and 25 had no fusion. Disc height was reduced at all levels independent of fusion. No difference in disc height and sagittal alignment was observed between patients fused and not fused. There were weak correlations, ranging from 0.04 to 0.36, between clinical and radiological parameters. Conclusion: Lumbar disc degeneration increased at all measured levels independent of fusion and correlated poorly with clinical outcome. PMID:23961300

  7. Recognition of distinctive patterns of gallium-67 distribution in sarcoidosis

    SciTech Connect

    Sulavik, S.B.; Spencer, R.P.; Weed, D.A.; Shapiro, H.R.; Shiue, S.T.; Castriotta, R.J. )

    1990-12-01

    Assessment of gallium-67 ({sup 67}Ga) uptake in the salivary and lacrimal glands and intrathoracic lymph nodes was made in 605 consecutive patients including 65 with sarcoidosis. A distinctive intrathoracic lymph node {sup 67}Ga uptake pattern, resembling the Greek letter lambda, was observed only in sarcoidosis (72%). Symmetrical lacrimal gland and parotid gland {sup 67}Ga uptake (panda appearance) was noted in 79% of sarcoidosis patients. A simultaneous lambda and panda pattern (62%) or a panda appearance with radiographic bilateral, symmetrical, hilar lymphadenopathy (6%) was present only in sarcoidosis patients. The presence of either of these patterns was particularly prevalent in roentgen Stages I (80%) or II (74%). We conclude that simultaneous (a) lambda and panda images, or (b) a panda image with bilateral symmetrical hilar lymphadenopathy on chest X-ray represent distinctive patterns which are highly specific for sarcoidosis, and may obviate the need for invasive diagnostic procedures.

  8. [Morphofunctional changes of coccyx area in posttraumatic coccygodynia].

    PubMed

    Brusko, A T; Nosov, A T; Shevchuk, A V

    2004-01-01

    For definition of a pathogenesis ofposttraumatic coccygodynia, a study of morpho-functional changes of the structures of coccyx's area was organized. The preparations of coccyx, removed during operative intervention from 23 different-aged patients with manifestations of disease were analyzed by roentgen, histological technique and a submicroscopy. In a cartilaginous tissue from patients with posttraumatic coccygodynia, dystrophic changes of chondrocytes down to their atrophy, a destruction of the basic material with partial replacement of a fibrillar cartilaginous tissue with a hyaline cartilage were observed with a different degree of manifestation. Vessels and sacrococcygeal nervous plexus were subjected to pathological changes. Increased post-traumatic mobility, alterations in the process of ossification, deceleration of physiological joining of coccyx vertebras and sacrococcygeal joint alter biomechanical properties of coccyx at sitting. These alterations lead to the long-lasting traumatization with degenerative - dystrophic changes, reinforcement of pain syndrome and manifestation of dysfunctions of organs of pelvis. PMID:15732768

  9. Food Irradiation Is Done in Grays, not Rads

    SciTech Connect

    Strom, Daniel J.

    2002-07-01

    One federal agency has chosen to use exclusively modern SI units of radiation dose in its regulations: the FDA. While not exactly hot news, this bold move by a U.S. government agency on November 26, 1997, should be noted by those who wish to encourage the switch from curies, working level months, rads, rems, and roentgens to becquerels, joule hours per cubic meter, grays, sieverts, and coulombs per kilogram. The regulation is 21 CFR 179, Irradiation in the Production, Processing, and Handling of Food. Specifically, 21 CFR 179.26 (b) 8. permits meat irradiation up to 4.5 kGy for refrigerated meat and 7.0 kGy for frozen meat. Prior to the 1997 addition, radiation doses had been quoted in grays (kGy) with rad (Mrad) values in parentheses. In the 1997 addition, the Mrads disappeared.

  10. Synthesis of europium- or terbium-activated calcium tungstate phosphors

    NASA Astrophysics Data System (ADS)

    Forgaciu, Flavia; Popovici, Elisabeth-Jeanne; Ungur, Laura; Vadan, Maria; Vasilescu, Marilena; Nazarov, Mihail

    2001-06-01

    Utilization of luminescent substances in various optoelectronic devices depends on their luminescent properties and sensitivity to various excitation radiation as well as on particle size distribution and crystalline structure of luminous powders. Calcium tungstate phosphors are well excited with roentgen radiation, so that they are largely used for manufacture of x-ray intensifying screens. Being sensitive to short UV-radiation as well, they could be utilized in Plasma Display Panels or in advertising signs fluorescent tubes. In order to diversify the utilization possibilities of this tungstate class, luminescent powders based on CaWO4:Eu3+ and CaWO4:Tb3+ were synthesized and characterized. As compared with the starting self-activated phosphor, larger excitation wavelength domain and emission colors from blue-to-green-to- yellow-to-red were obtained. The good UV excitability and variable luminescence color recommend these phosphors for optoelectronic device manufacture.

  11. The Nature of the Unidentified EUV Sources: Accreting Isolated Neutron Stars?

    NASA Technical Reports Server (NTRS)

    Madau, Piero

    1999-01-01

    The aims of this project were: (1) to investigate the nature of the EUVE (Extreme Ultraviolet Explorer Satellite) 'NOID' sources, objects detected in the EUV bandpass but with no previous identification at optical or other energies; (2) to study the possible association of NOID sources with nearby, isolated neutron stars among the 1e9 predicted to exist in the Galaxy. These dead radio pulsars have not been detected so far in large numbers, but accretion from the interstellar medium can make them bright at EUV wavelengths; and (3) to use the EUVE data to set constraints on neutron star evolution, accretion physics and population properties. The original objectives of our program remain relevant. Indeed, the level of research in this area has increased substantially since our proposal was submitted as a result of new data from the ROSAT (Roentgen Satellite).

  12. An intelligent ground operator support system

    NASA Technical Reports Server (NTRS)

    Goerlach, Thomas; Ohlendorf, Gerhard; Plassmeier, Frank; Bruege, Uwe

    1994-01-01

    This paper presents first results of the project 'Technologien fuer die intelligente Kontrolle von Raumfahrzeugen' (TIKON). The TIKON objective was the demonstration of feasibility and profit of the application of artificial intelligence in the space business. For that purpose a prototype system has been developed and implemented for the operation support of the Roentgen Satellite (ROSAT), a scientific spacecraft designed to perform the first all-sky survey with a high-resolution X-ray telescope and to investigate the emission of specific celestial sources. The prototype integrates a scheduler and a diagnosis tool both based on artificial intelligence techniques. The user interface is menu driven and provides synoptic displays for the visualization of the system status. The prototype has been used and tested in parallel to an already existing operational system.

  13. The axis of rotation of the ankle joint.

    PubMed

    Lundberg, A; Svensson, O K; Németh, G; Selvik, G

    1989-01-01

    The axis of the talo-crural joint was analysed by roentgen stereophotogrammetry in eight healthy volunteers. Examinations were performed at 10 degrees increments of flexion and pronation/supination of the foot as well as medial and lateral rotation of the leg. Results indicate that the talo-crural joint axis changes continuously throughout the range of movement. In dorsiflexion it tended to be oblique downward and laterally. In rotation of the leg, the axis took varying inclinations between horizontal and vertical. All axes in each subject lay close to the midpoint of a line between the tips of the malleoli. Our study indicates that the talo-crural joint axis may alter considerably during the arc of motion and differ significantly between individuals. This prompts caution in the use of hinge axes in orthoses and prostheses for the ankle. PMID:2915016

  14. DETECTION OF SMALL LESIONS OF THE LARGE BOWELBarium Enema Versus Double Contrast

    PubMed Central

    Robinson, J. Maurice

    1954-01-01

    Roentgen study with the so-called opaque barium enema with some modifications is superior to double contrast study as the primary means of demonstrating polyps in the colon as well as other lesions. The method described combines fluoroscopy, high kilovoltage radiography, fluoroscopically aimed spot films taken with compression, suction and evacuation studies. In this way unsuspected as well as suspected polyps can be demonstrated, particularly if attention is directed to the region where polyps are most likely to be foundnamely, the distal third of the large bowel. Double contrast study is quite valuable as a supplement to the modified single contrast barium enema, but it has not been sufficiently perfected to replace the modified opaque barium enema as a primary procedure. In many instances a combination of methods will, of course, be required. PMID:13209360

  15. The attosecond nonlinear optics of bright coherent X-ray generation

    NASA Astrophysics Data System (ADS)

    Popmintchev, Tenio; Chen, Ming-Chang; Arpin, Paul; Murnane, Margaret M.; Kapteyn, Henry C.

    2010-12-01

    The frequency doubling of laser light was one of the first new phenomena observed following the invention of the laser over 50 years ago. Since then, the quest to extend nonlinear optical upconversion to ever-shorter wavelengths has been a grand challenge in laser science. Two decades of research into high-order harmonic generation has recently uncovered several feasible routes for generating bright coherent X-ray beams using small-scale femtosecond lasers. The physics of this technique combines the microscopic attosecond science of atoms driven by intense laser fields with the macroscopic extreme nonlinear optics of phase matching, thus essentially realizing a coherent, tabletop version of the Roentgen X-ray tube.

  16. Delayed effects of external radiation exposure: A brief history

    SciTech Connect

    Miller, R.W.

    1995-11-01

    Within months of Roentgen`s discovery of X rays, severe adverse effects were reported, but not well publicized. As a result, over the next two decades, fluoroscope operators suffered lethal skin carcinomas. Later, case reports appeared concerning leukemia in radiation workers, and infants born with severe mental retardation after their mothers had been given pelvic radiotherapy early in pregnancy. Fluoroscopy and radiotherapy for benign disorders continued to be used with abandon until authoritative reports were published on the adverse effects of ionizing radiation by the U.S. NAS-NRC and the UK MRC in 1956. Meanwhile, exposure to the atomic bombs in Japan had occurred and epidemics of delayed effects began to be recognized among the survivors: cataracts, leukemia and severe mental retardation among newborn infants after intra-uterine exposure. No statistically significant excess of germ-cell genetic effects was detected by six clinical measurements, the F{sub 1} mortality, cytogenetic studies or biochemical genetic studies. Somatic cell effects were revealed by long-lasting chromosomal aberrations in peripheral lymphocytes, and somatic cell mutations were found at the glycophorin A locus in erythrocytes. Molecular biology is a likely focus of new studies based on the function of the gene for ataxia telangiectasia, a disorder in which children have severe, even lethal acute radiation reactions when given conventional doses of radiotherapy for lymphoma, to which they are prone. The tumor registries in Hiroshima and Nagasaki now provide incidence data that show the extent of increases in eight common cancers and no increase in eight others. The possibility of very late effects of A-bomb exposure is suggested by recent reports of increased frequencies of hyperparathyroidism, parathyroid cancers and certain causes of death other than cancer. 88 refs., 1 fig.

  17. eROSITA on SRG

    NASA Astrophysics Data System (ADS)

    Predehl, Peter; Andritschke, Robert; Becker, Werner; Bornemann, Walter; Bräuninger, Heinrich; Brunner, Hermann; Boller, Thomas; Burwitz, Vadim; Burkert, Wolfgang; Clerc, Nicolas; Churazov, Evgeniy; Coutinho, Diogo; Dennerl, Konrad; Eder, Josef; Emberger, Valentin; Eraerds, Tanja; Freyberg, Michael J.; Friedrich, Peter; Fürmetz, Maria; Georgakakis, Antonis; Grossberger, Christoph; Haberl, Frank; Hälker, Olaf; Hartner, Gisela; Hasinger, Günther; Hoelzl, Johannes; Huber, Heinrich; von Kienlin, Andreas; Kink, Walter; Kreykenbohm, Ingo; Lamer, Georg; Lomakin, Ilya; Lapchov, Igor; Lovisari, Lorenzo; Meidinger, Norbert; Merloni, Andrea; Mican, Benjamin; Mohr, Joseph; Müller, Siegfried; Nandra, Kirpal; Pacaud, Florian; Pavlinsky, Mikhail N.; Perinati, Emanuele; Pfeffermann, Elmar; Pietschner, Daniel; Reiffers, Jonas; Reiprich, Thomas; Robrade, Jan; Salvato, Mara; Santangelo, Andrea E.; Sasaki, Manami; Scheuerle, Hartmut; Schmid, Christian; Schmitt, Jürgen; Schwope, Axel D.; Sunyaev, Rashid; Tenzer, Christoph; Tiedemann, Lars; Xu, Weizong; Yaroshenko, Valeri; Walther, Sabine; Wille, Michael; Wilms, Jörn; Zhang, Yu-Ying

    2014-07-01

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian/German Spektrum-Roentgen-Gamma (SRG) mission which is now officially scheduled for launch on March 26, 2016. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5-2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters to redshifts z < 1 in order to study the large scale structure in the universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of a few million AGN, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including X-ray binaries, active stars and diffuse emission within the Galaxy. eROSITA is currently (June 2014) in its flight model and calibration phase. All seven flight mirror modules (+ 1 spare) have been delivered and measured in X-rays. The first camera including the complete electronics has been extensively tested (vacuum + X-rays). A pre-test of the final end-toend test has been performed already. So far, all subsystems and components are well within their expected performances.

  18. Pixel detectors for x-ray imaging spectroscopy in space

    NASA Astrophysics Data System (ADS)

    Treis, J.; Andritschke, R.; Hartmann, R.; Herrmann, S.; Holl, P.; Lauf, T.; Lechner, P.; Lutz, G.; Meidinger, N.; Porro, M.; Richter, R. H.; Schopper, F.; Soltau, H.; Strüder, L.

    2009-03-01

    Pixelated semiconductor detectors for X-ray imaging spectroscopy are foreseen as key components of the payload of various future space missions exploring the x-ray sky. Located on the platform of the new Spectrum-Roentgen-Gamma satellite, the eROSITA (extended Roentgen Survey with an Imaging Telescope Array) instrument will perform an imaging all-sky survey up to an X-ray energy of 10 keV with unprecedented spectral and angular resolution. The instrument will consist of seven parallel oriented mirror modules each having its own pnCCD camera in the focus. The satellite born X-ray observatory SIMBOL-X will be the first mission to use formation-flying techniques to implement an X-ray telescope with an unprecedented focal length of around 20 m. The detector instrumentation consists of separate high- and low energy detectors, a monolithic 128 × 128 DEPFET macropixel array and a pixellated CdZTe detector respectively, making energy band between 0.5 to 80 keV accessible. A similar concept is proposed for the next generation X-ray observatory IXO. Finally, the MIXS (Mercury Imaging X-ray Spectrometer) instrument on the European Mercury exploration mission BepiColombo will use DEPFET macropixel arrays together with a small X-ray telescope to perform a spatially resolved planetary XRF analysis of Mercury's crust. Here, the mission concepts and their scientific targets are briefly discussed, and the resulting requirements on the detector devices together with the implementation strategies are shown.

  19. Imaging the renal mass: a historical review.

    PubMed

    McClennan, Bruce L

    2014-11-01

    A matter of months after Roentgen's landmark discovery in 1895, Roentgen's rays were focused on diseases and disorders of the urinary tract, specifically the kidney. At the dawn of the 20th century, urologists in the United States and around the world quickly recognized that by using a variety of metal stylets and radiopaque contrast agents, such as silver salts, the upper urinary tract, namely the ureter, pelvis, and calyces, could be depicted with radiography. Renal cysts and tumors were diagnosed on the basis of deformities in the kidney. Retrograde pyelography dominated the imaging evaluation of the kidney until the discovery of a safe intravenous method for urinary tract imaging (ie, intravenous pyelography). Pioneers and pathfinders in the field of contrast media development and radiologic procedures helped give radiologists the lead role in the work-up of renal masses, an area where urologists once held forth. The subspecialty of uroradiology was born in the middle of the 20th century. Intravenous urography, nephrotomography, and diagnostic angiography with pharmacologic manipulation followed by cyst or mass puncture and biopsy yielded unrivaled specificity for the diagnosis and staging of benign and malignant renal masses. The advent of cross-sectional and multiplanar imaging and the profound effects they had and continue to have on the discovery and characterization of renal masses has been detailed in the pages of Radiology since the 1920s. Ultrasonography, nuclear imaging, computed tomographic scanning, magnetic resonance imaging, and positron emission tomography each have made a claim to a part of the imaging algorithm of modern uroradiologic practice. PMID:25340433

  20. The evolution of and challenges for industrial radiation processing2012

    NASA Astrophysics Data System (ADS)

    Berejka, A. J.; Cleland, M. R.; Walo, M.

    2014-01-01

    The evolution of industrial radiation processing is traced from Roentgen's discovery of X-radiation in 1895 by following the development of high current, electron beam accelerators (EB) throughout the twentieth century. Although Becquerel soon followed Roentgen with his discovery of what became to be known as radioactivity, electrical sources for ionizing radiation dominate industrial processing with there being more than ten times as many industrial installations using high current EB equipment than the facilities relying upon large concentrations of radioactive isotopes. In the 1950s, the discovery that ionizing radiation would enhance the value of what has become the world's largest volume commodity plastic, polyethylene (PE), opened the way for full scale commercial use of high current EB equipment. While the crosslinking of the PE insulation on wire became one of the first major industrial applications, other uses of EB processing soon followed. In the 1970s, low-energy, self-shielded EB equipment made the surface curing of inks, coatings and adhesives more industrially viable. In the early part of the twenty-first century, new market applications involving the low-energy EB surface decontamination of packaging materials emerged. This new area poses challenges for the metrology needed to control industrial processes, in that there is limited EB penetration into what have been used as dosimeters by industry. Major industrial use of radiation process is now over 50 years old. Because of the diversity of end-uses and the fact that the use of ionizing radiation in industry is a process technique, it is hard to quantify the value-added to numerous commercial products that benefit from this energy efficient process. It may be in excess of a trillion Euros in value-added to articles of commerce. In this milieu, there are some broad-based opportunities for research which are noted.

  1. Latitude and Longitude Patterns of Soft X-Rays Emitted from the Earth's Upper Atmosphere as Observed with the Coronas-F Spacecraft

    NASA Astrophysics Data System (ADS)

    Gusev, Anatoly; Spjeldvik, Walther; Martin, Inacio

    Long-term monitoring during 2001 through 2005 of the low energy 3-8 keV X-ray emission was carried out with CdTe solid state detector on Low Earth Orbit CORONAS-F spacecraft. Care was taken to exclude the sections of the spacecraft orbit where direct or scattered solar X-ray fluxes would reach the detector. We have found definite patterns as well as irregularities in these soft X-rays emanating from the upper Earth atmosphere. In the northern hemisphere we have found latitudinal distributions extending over +/- 10 degrees latitude centered on the middle latitudes and extending over half of the Earth latitude range. We report that the X-ray intensity is up to 10 kW in this soft X-ray band. Luminosity of the whole the Earth’s globe at altitude of 500 km amounts to several tens kW. The radiation possesses the seasonal variations; it intensity significantly depends on solar activity level. We reason that these X-ray fluxes can not be scattering solar roentgen ones as these photons are observed on night side of the Earth, and we note that solar roentgen emission has a little lower energy, typically less than about 2 keV. We surmise that the observed emission is mostly the result from Bremsstrahlung radiation due to magnetospheric electrons precipitating from the Earth’s radiation belts being influenced by electromagnetic disturbances of different origin (e.g., persistent ELF and VLF plasma waves in the inner magnetosphere, possible ducted lightning electromagnetic emissions, electromagnetic pulses in earthquakes, enhancement of plasma waves geomagnetic storms and/or substorms, etc.).

  2. Münsterberg's nightmare: psychology and history in fin-de-siècle Germany and America.

    PubMed

    Stoffers, Manuel

    2003-01-01

    This article demonstrates that Hugo Münsterberg's presidential address "Psychology and History," delivered to the American Psychological Association in 1898, should be understood in the German context of the 1890s. It constituted a response to a central feature of fin-de-siècle culture in Europe, the revolt against positivism. To be more precise, Münsterberg reacted against a new intellectual trend that was arising in Germany in the middle 1890s: the call for a historically oriented social psychology put forward by Wilhelm Dilthey-who was explicitly attacking Münsterberg's physiological conception of psychology-and new cultural historians like Karl Lamprecht and others who seemed to be putting Dilthey's program into practice. PMID:12720325

  3. Students explore history of the Göttingen Institute of Geophysics

    NASA Astrophysics Data System (ADS)

    Ritter, Joachim R. R.

    The Institute of Geophysics at the University of Gottingen, Germany has a long tradition that began long before its official founding in January 1898. Its history goes back to at least 1756, to the work on geophysical problems by Tobias Meyer, Carl-Friedrich GauS, and Wilhelm Weber. At the beginning of the 20th century, the first director of the institute, Emil Wiechert, established a seismological working group that was a worldwide leader in this type of research for the next 10 to 12 years. In those golden years of seismology at Gottingen, famous students and co-workers of Wiechert such as G. H. Angenheister, L. Geiger, B. Gutenberg, L. Mintrop, and K. Zoeppritz made fundamental discoveries.

  4. A history of erotic philosophy.

    PubMed

    Soble, Alan

    2009-01-01

    This essay historically explores philosophical views about the nature and significance of human sexuality, starting with the Ancient Greeks and ending with late 20th-century Western philosophy. Important figures from the history of philosophy (and theology) discussed include Sappho, Plato, Aristotle, St. Augustine, St. Jerome, the Pelagians, St. Thomas Aquinas, Michel de Montaigne, Rene Descartes, Thomas Hobbes, David Hume, Immanuel Kant, Søren Kierkegaard, Arthur Schopenhauer, Jeremy Bentham, John Stuart Mill, Karl Marx, Friedrich Engels, Sigmund Freud, Jean-Paul Sartre, Simone de Beauvoir, Wilhelm Reich, and Herbert Marcuse. Contemporary philosophers whose recent work is discussed include Michel Foucault, Thomas Nagel, Roger Scruton, Karol Wojtyla (Pope John Paul II), Catharine MacKinnon, Richard Posner, and John Finnis. To show the unity of the humanities, the writings of various literary figures are incorporated into this history, including Mark Twain, Arthur Miller, James Thurber, E. B. White, Iris Murdoch, and Philip Roth. PMID:19308838

  5. Elevational gradient of Hemiptera (Heteroptera, Auchenorrhyncha) on a tropical mountain in Papua New Guinea

    PubMed Central

    Wilson, Stephen W.; Soulier-Perkins, Adeline

    2015-01-01

    Malaise trap sampling of Hemiptera (Heteroptera; Auchenorrhyncha) was conducted at 500 m intervals along an elevational gradient from 200 m to 3,700 m on the east slope of Mount Wilhelm, Madang Province, Papua New Guinea. Hemiptera had a decrease in morphospecies richness and overall abundance with increasing elevation, however, the Heteroptera did not exhibit either pattern. A few species were relatively abundant at each elevation, whereas the majority of species were represented by ≤5 specimens. Morphospecies richness of Auchenorrhyncha, Cicadomorpha, Fulgoromorpha, Cicadellidae, Cixiidae, and Derbidae also decreased with increasing elevation but abundance decline was not significant due to the large number of specimens captured at 200 m relative to those captured at higher elevations. The percentage of Cicadomorpha specimens decreased with increasing elevation relative to that of the Fulgoromorpha which increased with increasing elevation. Environmental factors that may influence patterns of species richness along the elevational gradient are discussed. PMID:26056617

  6. ["Could not therefore the earth globe also be a large tourmaline?" A crystal, Lichtenberg and the polarity discussion before 1800].

    PubMed

    Wiesenfeldt, Gerhard; Breidbach, Olaf

    2012-01-01

    This paper focuses on the debate on one particular phenomenon of the research into electrical charge distribution prior to 1800: the description and interpretation of polarities observed on the tourmaline. We show that in the second half of the eighteenth century this crystal became a model to distinguish and categorize different qualities of charges (electric and magnetic fluids). It will become clear that the polarity detected on the tourmaline became a key concept for eighteenth century natural philosophy, which relied on analogizing operations. We illustrate this concentrating on Lichtenbergs first lecture at the Göttingen academy of science in 1778. Thus the concept of polarity is already a central ordering category before the beginnings of the speculative enterprise of idealistic Naturphilosophy. Consequently, the physicist Johann Wilhelm Ritter, who can be positioned in that context, consciously adheres to the experimental research tradition of polarities portrayed in this paper. PMID:23155759

  7. The blood from Auschwitz and the silence of the scholars.

    PubMed

    Müller-Hill, B

    1999-01-01

    The Kaiser Wilhelm Institute for Anthropology, Human Genetics and Eugenics in Berlin-Dahlem was the centre of scientific racism in Nazi Germany. Its bad history culminated in a research project to analyse the molecular basis of racial differences in the susceptibility to various infectious diseases such as tuberculosis. Josef Mengele, a former postdoc of the director of the institute, Otmar von Verschuer, collected blood samples and other material in Auschwitz from families and twins of Jews and Gypsies. The blood samples were analysed by Günther Hillmann in the Berlin laboratory of Nobel Prize winner Adolf Butenandt. Butenandt had just moved to Tübingen. The project was paid for by the Deutsche Forschungsgemeinschaft. Butenandt, Hillmann and von Verschuer made scientific careers in the Federal Republic. To the present day this past has not been acknowledged by the Max-Planck-Gesellschaft as part of its history. PMID:11197188

  8. Withstanding trauma: the significance of Emma Eckstein's circumcision to Freud's Irma dream.

    PubMed

    Bonomi, Carlo

    2013-07-01

    The author considers the medical rationale for Wilhelm Fliess's operation on Emma Eckstein's nose in February 1895 and interprets the possible role that this played in Freud's dream of Irma's injection five months later. The author's main argument is that Emma likely endured female castration as a child and that she therefore experienced the surgery to her nose in 1895 as a retraumatization of her childhood trauma. The author further argues that Freud's unconscious identification with Emma, which broke through in his dream of Irma's injection with resistances and apotropaic defenses, served to accentuate his own "masculine protest". The understanding brought to light by the present interpretation of Freud's Irma dream, when coupled with our previous knowledge of Freud, allows us to better grasp the unconscious logic and origins of psychoanalysis itself.(1.) PMID:23824652

  9. [On the road to a new humanity: the reception of psychoanalysis in the early Kinderladen movement].

    PubMed

    Kauders, Anthony D

    2014-01-01

    In the late 1960s a group of students in West Germany founded the so-called Kinderläden (day care centers) in order to experiment with new forms of early childhood education. Members of the early Kinderladen movement in particular pursued a radically utopian approach that, they hoped, would engender new human beings. With the aid of psychoanalytic writings, especially those of Wilhelm Reich, they sought to create subjects that would overcome repressive bourgeois norms and live out their sexuality freely. This reliance on Reich entailed a new interpretation of the "base", as psychoanalytic drive theory supplanted Marxist theory. As such, the early Kinderladen ac- tivists regarded the "basis" of society in biological, psychological, and pedagogic rather than economic terms. PMID:25872313

  10. Images and Meaning-Making in a World of Resemblance: The Bavarian-Saxon Kidney Stone Affair of 1580

    PubMed Central

    Stein, Claudia

    2015-01-01

    This article de-constructs and re-constructs the dynamic of a sixteenth-century political dispute between the Catholic Bavarian Duke Wilhelm V and the Protestant Saxon Elector August I. By focusing on the visual imagery which ignited the dispute, the paper explores sixteenth-century ‘ways of seeing’ and the epistemic role realistic images played in the production of knowledge about the natural world. While the peculiar dynamic of the affair is based on a specific understanding of the evidential role of images, the paper also argues that the wider socio-cultural context, in particular certain strategies of truth-telling, provide further clues as to the dynamic and closure of the affair. PMID:26290618

  11. Physics, ballistics, and psychology: a history of the chronoscope in/as context, 1845-1890.

    PubMed

    Schmidgen, Henning

    2005-02-01

    In Wilhelm Wundt's (1832-1920) Leipzig laboratory and at numerous other research sites, the chronoscope was used to conduct reaction time experiments. The author argues that the history of the chronoscope is the history not of an instrument but of an experimental setup. This setup was initially devised by the English physicist and instrument maker Charles Wheatstone (1802-1875) in the early 1840s. Shortly thereafter, it was improved by the German clockmaker and mechanic Matthäus Hipp (1813-1893). In the 1850s, the chronoscope was introduced to ballistic research. In the early 1860s, Neuchâtel astronomer Adolphe Hirsch (1830-1901) applied it to the problem of physiological time. The extensions and variations of chronoscope use within the contexts of ballistics, physiology, and psychology presented special challenges. These challenges were met with specific attempts to reduce the errors in chronoscopic experiments on shooting stands and in the psychological laboratory. PMID:16021765

  12. [Ophthalmologists in the proximity of Adolf Hitler].

    PubMed

    Rohrbach, J M

    2012-10-01

    Adolf Hitler met or at least knew about 5 ophthalmologists. The chair of ophthalmology in Berlin, Walther Löhlein, personally examined Hitler's eyes at least two times. The chair of ophthalmology in Breslau, Walter Dieter, developed "air raid protection spectacles" with the aid of high representatives of the NS-system and probably Adolf Hitler himself. Heinrich Wilhelm Kranz became rector of the universities of Giessen and Frankfurt/Main. He was known as a very strict advocate of the NS-race hygiene. Werner Zabel made plans for Hitler's diet and tried to interfere with Hitler's medical treatment. Finally, Hellmuth Unger was an influential representative of the medical press and a famous writer. Three of his novels with medical topics were made into a film which Hitler probably saw. Hitler had, so to say, a small "ophthalmological proximity" which, however, did not play a significant role for himself or the NS-state. PMID:22664943

  13. Plant breeding on the front: imperialism, war, and exploitation.

    PubMed

    Elina, Olga; Heim, Susanne; Roll-Hansen, Nils

    2005-01-01

    This paper examines the development of plant-breeding science in the context of the booming genetic research and autarky policy of the 1930s as well as during World War II in National Socialist-occupied Europe. Soviet scientists, especially Nikolai Vavilov and his VIR institute, had a leading position in the international plant-breeding science of the 1920s. During World War II, German scientists, namely experts from the Kaiser Wilhelm Institute for Plant Breeding, usurped Soviet institutes and valuable seed collections. In contrast, plant-breeding research in occupied Scandinavia continued with relatively little disturbance. The paper compares behavior of German, Soviet, and Norwegian plant-breeding scientists under the Nazi regime. PMID:20503762

  14. The linguistic repudiation of Wundt.

    PubMed

    Nerlich, B; Clarke, D D

    1998-08-01

    Wilhelm Wundt's influence on the development of linguistics and psychology was pervasive. The foundations for this web of influence on the sciences of mind and language were laid down in Wundt's own research program, which was quite different from other attempts at founding a new psychology, as it was deeply rooted in German philosophy. This resulted in certain gaps in Wundt's conception of mind and language. These gaps provoked a double repudiation of Wundt's theories, by linguists and psychologists. The psychological repudiation has been studied by historians of psychology, and the linguistic repudiation has been studied by historians of linguistics. The intent of this article is to bring the linguistic repudiation to the attention of historians of psychology, especially the one outlined by two important figures in the history of psychology: Karl Buhler and George Mead. PMID:11620314

  15. Kant and the development of the human and cultural sciences.

    PubMed

    Makkreel, Rudolf A

    2008-12-01

    Starting with Kant's doubts about psychology as a natural science capable of explaining human behavior, several alternative attempts to conceive of human life, culture and history are examined. Kant proposes an anthropology that will be a commonly useful human science rather than a universally valid natural science. This anthropology relates to philosophy as a mode of world-cognition. Special attention is given to how Kant's theory of right can help define our appropriate place in a communal world. The different ways in which Wilhelm Dilthey and Hermann Cohen respond to Kant's idea of legitimate appropriation are also considered. The various tasks that descriptive elucidation, explanation, reflective understanding, characterization and interpretation can perform for the human and cultural sciences are examined throughout the essay. PMID:19391373

  16. Nursing knowledge and human science: ontological and epistemological considerations.

    PubMed

    Mitchell, G J; Cody, W K

    1992-01-01

    This article examines the meaning of human science in relation to extant nursing knowledge. The origins of the human science tradition are traced to the philosopher Wilhelm Dilthey, who challenged the dominance of the positivist perspective for generating knowledge of the human lifeworld. Specific ontological and epistemological criteria for human science are proposed. Four nursing frameworks, Paterson and Zderad's humanistic nursing, Newman's model of health as expanding consciousness, Watson's human science and human care, and Parse's theory of human becoming, are found to have consistencies and inconsistencies with the human science tradition. It is proposed that the human science perspective is present in and will continue to be reflected in the evolution of nursing science. PMID:1584506

  17. [Psychiatry as cultural science: considerations following Max Weber].

    PubMed

    Bormuth, M

    2010-11-01

    Psychiatry can be seen as a natural and cultural science. According to this the postulate of freedom is its strong value judgment. Since the times of enlightenment it has been described metaphorically by the myth of the expulsion from Paradise. Following Max Weber and Wilhelm Dilthey, Karl Jaspers has introduced this perspective into psychiatry. His strict dichotomy between explaining and understanding has later been critically revised by Werner Janzarik and Hans Heimann. Their concepts of structure dynamic, of pathography and of anthropology are closer to Max Weber who connected natural and cultural sciences in a much stronger way. Especially the pathographic example of Nietzsche allows to demonstrate the differences between Jaspers and the later psychopathologists of the Heidelberg and Tübingen schools. PMID:20676601

  18. Does Cometary Panspermia Falsify Dark Energy?

    NASA Astrophysics Data System (ADS)

    Gibson, Carl H.

    2011-10-01

    The 2011 Nobel Prize for physics has been awarded to Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess "for the discovery of the accelerating expansion of the Universe through observations of distant supernovae", judged to be the "most important discovery or invention within the field of physics" (Excerpt from the will of Alfred Nobel). Are we forced by this claimed discovery to believe the universe is dominated by anti- gravitational dark energy? Can the discovery be falsified? Because life as we observe it on Earth is virtually impossible by the standard ΛCDMHC model, extraterrestrial life and cometary panspermia may provide the first definitive falsification of a Nobel Prize in Physics since its first award in 1901 to Wilhelm Röntgen for his discovery of X-rays.

  19. X-rays for medical use

    NASA Astrophysics Data System (ADS)

    Hessenbruch, A.

    1995-11-01

    1995 is the centenary of the discovery of X-rays by the German physicist Wilhelm C Rontgen. In the past hundred years, the new rays have developed from being unknown to finding application in many walks of life, not least in medicine. This is so much so that in common speech the word `x-ray` refers not to a form of radiation but to an X-ray photograph taken for the purposes of diagnosis (as in: `I had an X-ray done to see if my leg was broken`). X-rays are now used routinely, and they are used both for diagnosis and for therapy. This paper will give an outline of the use of X-rays in medicine throughout our present century.

  20. Since 1895, orthopaedic surgery relies on x-ray imaging: a historical overview from discovery to computed tomography.

    PubMed

    Van Tiggelen, R

    2001-10-01

    The first application of x-ray techniques to human beings was made in Germany by Wilhelm Conrad Röntgen in November 1895. From this first use, different groups became interested in creating and improving the technical devices. Focusing on Germany, in honour of the centenary of the awarding of the first Nobel Prize in Physics to Röntgen in 1901, we present some of the milestones in x-ray imaging, from the first pioneer's approach on glass plates, cathode x-ray tubes, fluoroscopy, earlier communications leading to x-ray films and screens, rotating x-ray tubes, tomography and CT, classic textbooks, radioprotection aspects, as well as some contributions in radiological techniques and orthopedic pathology. PMID:11725562

  1. The use of hormonal therapy with radiotherapy for prostate cancer: analysis of prospective randomised trials.

    PubMed

    Gottschalk, A R; Roach, M

    2004-03-01

    In 1901, Wilhelm Conrad Röntgen won the Nobel prize in Physics for his discovery of the Röntgen rays or, as he himself called them, X-rays. In 1966, Dr Charles Brenton Higgins won the Nobel Prize in Medicine for his breakthroughs concerning hormonal treatment of prostatic cancer. After 31 years, in 1997, the first prospective randomised trials of the combination of hormonal therapy and radiation therapy were published, showing increased survival when compared to radiation therapy alone for patients with prostate cancer. Since 1997, many investigators have published trials combining hormonal and radiation therapy for prostate cancer. This minireview will address the largest and most influential of these trials, and attempt to guide physicians in selecting the appropriate patients for this combined approach. PMID:14997188

  2. Since 1895, orthopaedic surgery needs X-ray imaging: a historical overview from discovery to computed tomography.

    PubMed

    Van Tiggelen, R

    2001-01-01

    The first application of X-ray techniques to human beings was made in Germany by Wilhelm Conrad Röntgen in November 1895. From this first use, different groups became interested in creating and improving the technical devices. Focusing on Germany, in honour of the centenary of the awarding of the first Nobel Prize in Physics to Röntgen in 1901, we present some of the milestones in X-ray imaging, from the first pioneer's approach on glass plates, cathode X-ray tubes, fluoroscopy, earlier communications leading to X-ray films and screens, rotating xray tubes, tomography and CT, classic textbooks, radioprotection aspects, as well as some contributions in radiological techniques and orthopedic pathology. PMID:11757678

  3. [Precarious matters. The radium economy, episteme of risk and the emergence of tracer technique in national socialism].

    PubMed

    von Schwerin, Alexander

    2009-01-01

    Following the traces of radioactive material is--as scholars have recently shown--a valuable historical approach in order to evaluate the material 'factor' of science in action. Even though the origins of materials like radium and artificial isotopes are quite different, their circulation is interconnected. A material pathway can be drawn from the radium industry to the scientific rise of artificial isotopes as indicator substances in the 1930s, continuing to the building of networks by German scientists working for the war efforts. Also, this pathway reveals the role of radiation protection in establishing that material culture. Finally, the dynamics of material traces and institutional linkages is shown by the tracer work of biophysicists and radiation biologists working at the Genetic Department of the Kaiser Wilhelm Institute for Brain Research in Berlin and at the Institut de Chimie Nucléaire at Paris, which at that time was occupied by German troops. PMID:19831247

  4. Back to the future for wound care?

    PubMed

    Kirkpatrick, J J; Curtis, B; Naylor, I L

    1996-01-01

    The European Renaissance was a time of enormous change and rapid progress in the arts, sciences, and medicine. A glimpse of wound care in the last phase of the European Renaissance is provided by the analysis of work by Wilhelm Fabry, the "father of German surgery," as provided in his book De Combustionibus ("Burns") which details his range of treatments for the burn wound, as well as his approach to the later problems of scarring and contracture. We describe some of the historic events which may have stimulated Fabry's writings, in particular, the influences passed down from the medical school of Padua which thereby advanced the cause of wound care and surgery. Finally, we briefly explore the potential of such an approach to the works of our medical forefathers. PMID:17177728

  5. [From the history of Roger commentators].

    PubMed

    Karpp, Gerhard; Riha, Ortrun

    2015-01-01

    The biblical manuscript A 12, preserved in Duesseldorf's Federal and University Library (Universitaets- und Landesbibliothek Duesseldorf), dates from the mid-13th century. In the course of its scholarly analysis, a piece of parchment was found in the interior board, where a fragment of a surgical text is written on. Judging from the writing, the original manuscript came from southern France (Montpellier) and dates from the late 13th century. Several pas- sages quote "M[agister] W[ilhelmus] de Congenis", but the text bears only a vague resem- blance to Pagel's (1891) and Sudhoff s (1918) editions. Upon the other hand, the author was guided by Roger Frugardi's 'Chirurgia', which presumably gave the structure for Wilhelm's lectures. The edition of the fragmentary text presents a yet unknown example of student notes referring to William of Congenis and illustrates the complex history of Roger commentaries. PMID:26427163

  6. Purges in comparative perspective: Rules for exclusion and inclusion in the scientific community under political pressure.

    PubMed

    Beyler, Richard; Kojevnikov, Alexei; Wang, Jessica

    2005-01-01

    During the intense political upheaval that dominated the middle decades of the twentieth century, modern states intensified their drives to discipline broad sectors of society and ensure their political reliability. Subjected to such pressures, scientific institutions faced the challenge of admitting new, officially mandated criteria into the regulation of scientific life. We examine the effects of these policies on the Kaiser Wilhelm Society in National Socialist Germany, the Max Planck Society in occupied Germany after 1945, the USSR Academy of Sciences throughout the Stalin era, and the National Academy of Sciences in early cold war America. In all these cases, while academic elites largely accepted the required radical changes in the rules for membership in the scientific community, they also sought to manipulate the process to their own institutional advantage. PMID:20503757

  7. Elevational gradient of Hemiptera (Heteroptera, Auchenorrhyncha) on a tropical mountain in Papua New Guinea.

    PubMed

    Le Cesne, Maxime; Wilson, Stephen W; Soulier-Perkins, Adeline

    2015-01-01

    Malaise trap sampling of Hemiptera (Heteroptera; Auchenorrhyncha) was conducted at 500 m intervals along an elevational gradient from 200 m to 3,700 m on the east slope of Mount Wilhelm, Madang Province, Papua New Guinea. Hemiptera had a decrease in morphospecies richness and overall abundance with increasing elevation, however, the Heteroptera did not exhibit either pattern. A few species were relatively abundant at each elevation, whereas the majority of species were represented by ≤5 specimens. Morphospecies richness of Auchenorrhyncha, Cicadomorpha, Fulgoromorpha, Cicadellidae, Cixiidae, and Derbidae also decreased with increasing elevation but abundance decline was not significant due to the large number of specimens captured at 200 m relative to those captured at higher elevations. The percentage of Cicadomorpha specimens decreased with increasing elevation relative to that of the Fulgoromorpha which increased with increasing elevation. Environmental factors that may influence patterns of species richness along the elevational gradient are discussed. PMID:26056617

  8. Summary and Outlook

    NASA Astrophysics Data System (ADS)

    Poprawe, Reinhart

    Wilhelm von Humboldt (1767-1835) recognized the necessity of the coherence of research and education about 200 years ago. Today we see a third component coming in simultaneously: innovation. Not that this third aspect gained key importance only recently, but the demands for handling the increasing complexity of innovation have grown dramatically. Innovations need vertically structured processes, i.e., from simultaneous consideration of the product definition, the market, and recognition of relevant technologies all the way to the related fundamental research. The deeper the consideration, the greater the sustainability of the innovation. By definition, an innovation is first of all something new. There is still no scale to measure innovation, but it seems reasonable to define an innovation as any new process, technology, or product that leads to a quantitative economical benefit.

  9. Jung's quest for the Aurora consurgens.

    PubMed

    Haaning, Aksel

    2014-02-01

    The paper focuses on the year 1929 when Jung published 'A European commentary' to Richard Wilhelm's German translation of the Taoist text The Secret of the Golden Flower. This shows that Jung had already started on the track of European alchemy by following up Conrad Waldkirch's preface in Artis Auriferae (1593); and it raises the question of whether this could be the possible missing link to Jung's subsequent research in Alchemy and Hermetic Philosophy in the years to come. It is argued that here was the beginning of Jung's quest for the Aurora consurgens, the publication of which concludes the Mysterium Conuinctionis more than twenty years later. It is further maintained that this choice of the Aurora is a profound expression of Jung's ambition to revitalize the past from within the individual, and helps explain Jung's deep concern with the welfare and future of modern society. PMID:24467350

  10. Hilpoltstein at Johann Christoph Sturm's times (German Title: Hilpoltstein zu Zeiten Johann Christoph Sturms)

    NASA Astrophysics Data System (ADS)

    Platz, Kai Thomas

    After an overview on the foundations of research, the conditions inside the town of Hilpoltstein in the first half of the 17th century are described. Since Hilpoltstein was situated at the road from Nuremberg to Munich, and thus at one of the most important north-south trading routes of medieval times, the town florished in economic terms at the beginning of the 17th century. Afterwards, however, the inhabitants had to suffer religious troubles, since the count palatine Wolfgang Wilhelm converted to catholicism. We collect the traces of the Sturm family in Hilpoltstein that still exist today, and complete the picture by giving an overview of the architectural, commercial and social conditions of those times.

  11. Scientific Psychology in the 18th Century: A Historical Rediscovery.

    PubMed

    Schwarz, Katharina A; Pfister, Roland

    2016-05-01

    As early as 1783, the almost forgotten philosopher, metaphysicist, and psychologist Ferdinand Ueberwasser (1752-1812) designated himself "Professor für empirische Psychologie und Logik" (professor of empirical psychology and logic) at the University of Münster, Germany. His position was initiated and supported by the minister and educational reformer Franz von Fürstenberg (1729-1810), who considered psychology a core scientific discipline that should be taught at each school and university. At the end of the 18th century, then, psychology seems to have been on the verge of becoming an independent academic discipline, about 100 years before Wilhelm Wundt founded the discipline's first official laboratory. It seems surprising that Ueberwasser's writings-including a seminal textbook on empirical psychology-have been almost entirely overlooked in most historical accounts. We focus on this important founding moment of psychological science and on the circumstances that eventually brought this seminal development to a halt. PMID:27217252

  12. Production and properties of the heaviest elements. Status and perspectives

    NASA Astrophysics Data System (ADS)

    Backe, H.; Heßberger, F. P.; Sewtz, M.; Türler, A.

    2007-10-01

    This article reviews the following topics which were discussed at the 375th Wilhelm and Else Heraeus-Seminar Workshop on the Atomic Properties of the Heaviest Elements held from September 25 27, 2006 at the Abtei Frauenwörth im Chiemsee, Germany: (i) the recent progress in the production of the heaviest elements, the investigation of their nuclear structure, and prospects for direct mass measurements in Penning traps. (ii) Recent studies of their chemical properties with the aid of volatile species and single-atom aqueous-phase chemistry; (iii) the current status and future prospects for the investigation of atomic and ionic properties such as optical spectroscopy in gas cells and ion traps, including fully relativistic calculations of the atomic level structure with predictions for the element nobelium; and (iv) ionic charge radii measurements in buffer gas filled drift cells, and ion chemical reactions in the gas phase.

  13. Instead of Erklären and Verstehen: William James on Human Understanding

    NASA Astrophysics Data System (ADS)

    Leary, David E.

    Perhaps more than any other American psychologist and philosopher, William James (1842-1910) was intimately familiar with contemporary European thought and debate, including the discussion of Erklären and Verstehen advanced by Wilhelm Dilthey (1833-1911) and others around the turn of the twentieth century. Even before this discussion was initiated, James had been dealing with related issues, pondering alternative solutions, and formulating his own original views on human understanding. These views coalesced in a distinctive approach to cognition. Fundamental to this approach was a belief in possibility and probability as innate features of the physical as well as mental manifestations of the universe. Also fundamental was a conviction that understanding is understanding, regardless of its viewpoint, object, or label as either "descriptive" or "explanatory."

  14. Social Science Between Neo-Kantianism and Philosophy of Life: The Cases of Weber, Simmel, and Mannheim

    NASA Astrophysics Data System (ADS)

    Šuber, Daniel

    In recent years, a group of social scientists have credited Wilhelm Dilthey with the status of a "classical sociological theorist" (Bakker 1999) and a key figure with regard to the establishment of the social sciences since the last decades of the nineteenth century.1 Such evaluations stand in distinct contrast to Dilthey's reputation as a firm critic of sociology on the one hand and his dubious standing within his proper field, philosophy, on the other, where he is perceived as a failed epistemologist. Generally, his influence on social and cultural science is associated with his notion of Erleben and understanding as fundamental categories for the interpretive sciences and their unique relatedness to their particular subject. On the basis of this starting point, he eventually established a division between Verstehen and Erklären and, correspondingly, human and natural sciences.

  15. [The "diagnosis" in the light of Charles S. Peirce, Sherlock Holmes, Sigmund Freud and modern neurobiology].

    PubMed

    Adler, R H

    2006-05-10

    A diagnostic hypothesis is a causa ficta. It is an assumption, suitable to explain phenomena, which are not yet proven to be the only and valid explanation of the observed. One of Wilhelm Hauff's faitales illustrates how a hypothesis is generated. It is based on the interpretation of signs. Signs are of an ikonic, an indexical or a symbolic nature. According to S. Peirce, a hypothesis is created by abduction, to Conan Doyle's Sherlock Holmes by immersion into thoughts, and to S. Freud by free floating attention. The three procedures are alike. Neurobiological structures and functions, which correspond to these processes, are described; especially the emotional-implicite memory. The technique of hypothesis-generation is meaningful to clinical medicine. PMID:16722205

  16. "Cosmomorphistic geometry" in the unconscious geometry of Johannes Kepler

    NASA Astrophysics Data System (ADS)

    Adam, Adolf

    Some mathematical aspects of the Music theory by Johannes Kepler are discussed, paying a special attention to the book "De harmonice mundi". Other scientists interested in Music theory are mentioned throughout the paper: The Pythagorean school, Klaudios Ptolemaios, Leonard Euler, Gottfried Wilhelm Leibniz, Christian von Goldbach, Hermann Ludwig Ferdinand von Helmholz, Karl Friedrich Gauss. The relation with the ancient chinese schools of cosmography has been discussed: From the the Pythagorean to the ancient Chinese schools of cosmography we find arithmo-geometrical applications of numbers which are emblematic, hold meaning or represent the essence of things, the author writes. It was Johannes Kepler who taught us this "transconstructive method" of forming classical and ancient begginings of structuralistic thinking into a system from which deductions can readily be made.

  17. Hermann von Helmholtz and his students

    NASA Astrophysics Data System (ADS)

    Mulligan, Joseph F.

    1989-01-01

    During the years 1871-1888, when Hermann von Helmholtz was professor of physics at the University of Berlin, physicists from all over the world flocked to Berlin to study and do research with him. Among these were the German physicists Max Planck, Heinrich Kayser, Eugen Goldstein, Wilhelm Wien, and Heinrich Hertz, and Americans Henry Rowland, A. A. Michelson, and Michael Pupin. Examples of Helmholtz's scientific and personal interactions with these students and research associates show why he is justly considered the outstanding physics mentor of the 19th century. Both his ideas and his students played a major role in the development of physics in the late 19th and early 20th centuries.

  18. Contributions to the History of Astronomy, Vol. 8 (German Title: Beiträge zur Astronomiegeschichte, Band 8)

    NASA Astrophysics Data System (ADS)

    Dick, Wolfgang R.; Hamel, Jürgen

    The contributions span a time interval of more than 450 years. There are biographical investigations on Georg Joachim Rheticus, C.W.A. von Wahl and K.F. Heym, investigation on a reprint of a chapter of the principal work of Nicolaus Copernicus, on Christoph Scheiner and the "camera obscura", and, with respect to the history of timekeeping, on the "big Nuremberg clock". 19th century topics are: a contribution on the honorary doctorate of Joseph Fraunhofer, and on the construction of a lunar globe by Wilhelmine Witte, while the report on Friedrich Wilhelm Bessel and the cholera pandemia in Königsberg in the year 1831 gives a view into everyday life of scientists. 20th century topics are: the contributions on Bruno Thüring in Vienna and his relations with national socialism, as well as on Arthur Beer, Albert Einstein and the Warburg library. The book concludes by short communications, obituaries and book reviews.

  19. August Rauber (1841-1917): from the primitive streak to Cellularmechanik.

    TOXLINE Toxicology Bibliographic Information

    Brauckmann S

    2006-01-01

    In the early 19th century Karl Ernst von Baer initiated a new research program searching for the mechanisms by which an egg transforms itself into an embryo. August Rauber (1841-1917) took up this challenge. He considered the phylogenetic principle as the right tool to explain the similitude of embryogenetic processes. In extending Baer's approach, he combined comparative embryology and histology in his studies of avian and mammalian embryos. His earlier work demonstrated that the two-layered chick embryo is a modified gastrula and not a "disc" as Wilhelm His had claimed. From the 1880s onwards, he concentrated on the issue of how the development of germ layers is related to tissue differentiation. To address this, he studied the blastopore, epiblast, primitive streak, teratology and the relative importance of nucleus and cytoplasm in heredity. This paper reconstructs some of Rauber's work and concludes that his observations and reflections constituted a new approach combining embryology and histology with "phylogenetic" reasoning.

  20. Gradiva: freud, fetishism, and Pompeian Fantasy.

    PubMed

    Fletcher, John

    2013-10-01

    This paper is a critical reconsideration of Freud's analysis (1907) of Wilhelm Jensen's novella Gradiva: A Pompeian Fantasy (1903). Freud's interest was aroused by the parallels between Jensen's presentation of dreams and Freud's model of dream formation just published in The Interpretation of Dreams (1900). Freud also acclaims Jensen's presentation of the formation and "cure" of his protagonist's delusion about a marble bas-relief of a woman walking. This paper argues for the centrality of the phenomenon of fetishism, briefly considered but excluded from Freud's analysis. The fantasy of Gradiva as "the necessary conditions for loving" (Freud 1910, pp. 165-166) is also a key thesis of the essay, which makes use of the newly translated Freud-Jensen correspondence contained in this article's Appendix. PMID:24194488

  1. The Politics of Forgetting: Otto Hahn and the German Nuclear-Fission Project in World War II

    NASA Astrophysics Data System (ADS)

    Sime, Ruth Lewin

    2012-03-01

    As the co-discoverer of nuclear fission and director of the Kaiser Wilhelm Institute for Chemistry, Otto Hahn (1879-1968) took part in Germany`s nuclear-fission project throughout the Second World War. I outline Hahn's efforts to mobilize his institute for military-related research; his inclusion in high-level scientific structures of the military and the state; and his institute's research programs in neutron physics, isotope separation, transuranium elements, and fission products, all of potential military importance for a bomb or a reactor and almost all of it secret. These activities are contrasted with Hahn's deliberate misrepresentations after the war, when he claimed that his wartime work had been nothing but "purely scientific" fundamental research that was openly published and of no military relevance.

  2. The tragic and the metaphysical in philosophy and psychoanalysis.

    PubMed

    Stolorow, Robert D; Atwood, George E

    2013-06-01

    This article elaborates a claim, first introduced by Wilhelm Dilthey, that metaphysics represents an illusory flight from the tragedy of human finitude. Metaphysics, of which psychoanalytic metapsychologies are a form, transforms the unbearable fragility and transience of all things human into an enduring, permanent, changeless reality, an illusory world of eternal truths. Three "clinical cases" illustrate this thesis in the work and lives of a philosopher and two psychoanalytic theorists: Friedrich Nietzsche and his metaphysical doctrine of the eternal return of the same, Sigmund Freud and his dual instinct theory, and Heinz Kohut and his theoretical language of the self. It is contended that the best safeguard against the pitfalls of metaphysical illusion lies in a shared commitment to reflection on the constitutive contexts of all our theoretical ideas. PMID:23638662

  3. Barrow, Leibniz and the geometrical proof of the fundamental theorem of the calculus.

    PubMed

    Nauenberg, Michael

    2014-07-01

    In 1693, Gottfried Wilhelm Leibniz published in the Acta Eruditorum a geometrical proof of the fundamental theorem of the calculus. It is shown that this proof closely resembles Isaac Barrow's proof in Proposition 11, Lecture 10, of his Lectiones Geometricae, published in 1670. This comparison provides evidence that Leibniz gained substantial help from Barrow's book in formulating and presenting his geometrical formulation of this theorem. The analysis herein also supports the work of J. M. Child, who in 1920 studied the early manuscripts of Leibniz and concluded that he had frequently copied his diagrams from Barrow's book, but without acknowledgement. It is also shown that the diagram of Leibniz associated with his 1693 proof has often been reproduced with errors that make some aspects of his text difficult to comprehend. PMID:24908795

  4. [Schelling and experiential science].

    PubMed

    Breidbach, Olaf

    2004-01-01

    Schelling's philosophy of nature is shown to be part of the scientific discussions of his day, not set apart from it. His terminology describing the potentialities and polarities of nature was formed during Schelling's collaboration with the physicist Johann Wilhelm Ritter. This scientist adopted the schema Schelling had developed for the categorization of natural phenomena to describe the peculiar facts that interested him in his area of research. Thus Ritter was able to develop a classification of the various phenomena of animal galvanism. Thus it can be shown that the idealistic "Naturphilosophie" was part of the scientific culture of about 1800. It is to be interpreted as philosophy of science and has to be evaluated not only in a philosophically systematic way but in particular in its influence on the way scientific categories were ordered at the time. Thereby it can be shown that the idealistic vocabulary had close correspondence to French morphology and English Natural Theology. PMID:15730143

  5. The origin of the vertebrate skeleton

    NASA Astrophysics Data System (ADS)

    Pivar, Stuart

    2011-01-01

    The anatomy of the human and other vertebrates has been well described since the days of Leonardo da Vinci and Vesalius. The causative origin of the configuration of the bones and of their shapes and forms has been addressed over the ensuing centuries by such outstanding investigators as Goethe, Von Baer, Gegenbauer, Wilhelm His and D'Arcy Thompson, who sought to apply mechanical principles to morphogenesis. However, no coherent causative model of morphogenesis has ever been presented. This paper presents a causative model for the origin of the vertebrate skeleton, based on the premise that the body is a mosaic enlargement of self-organized patterns engrained in the membrane of the egg cell. Drawings illustrate the proposed hypothetical origin of membrane patterning and the changes in the hydrostatic equilibrium of the cytoplasm that cause topographical deformations resulting in the vertebrate body form.

  6. Aerodynamics and mathematics in National Socialist Germany and Fascist Italy: a comparison of research institutes.

    PubMed

    Epple, Moritz; Karachalios, Andreas; Remmert, Volker R

    2005-01-01

    The article is concerned with the mathematical sciences in National Socialist Germany and Fascist Italy, with special attention to research important to the war effort. It focuses on three institutional developments: the expansion of the Kaiser Wilhelm Institute for Fluid Dynamics in Göttingen, the foundation of the Reich Institute for Mathematics in Oberwolfach (Black Forest), and the work of the Istituto Nazionale per le Applicazioni del Calcolo in Rome. All three developments are embedded in the general political background, thus providing a basis for comparative conclusions about the conditions of the mathematical sciences and military-related research in Germany and Italy. It turns out that in both countries, the increasing demand for mathematical knowledge in modern warfare led to the establishment of "extra-university" national institutions specifically devoted to mathematical research. PMID:20503761

  7. Redescription of Jenkina articulata Brøndsted from the deep Eckström Shelf, E-Weddell Sea, Antarctica and a comment on the possible mass occurrence of this species

    NASA Astrophysics Data System (ADS)

    Janussen, Dorte; Tore Rapp, Hans

    2011-10-01

    This paper reports on an unexpected large catch of the rare calcareous sponge species Jenkina articulataBrøndsted, 1931, taken in the Antarctic Weddell Sea during the ANT XXIV/2-SYSTCO expedition in January 2008. This species is only known from the original description from two specimens collected from the type locality off Wilhelm II-Land. During the SYSTCO expedition more than 60 specimens were collected using an Agassiz trawl at 600 m depth on the Eckström Shelf, Eastern Weddell Sea. Based on this collection, we give a redescription of the incompletely known species, place the locality of catch in a major context, and discuss possible explanations for the rich occurrence of this species in the sponge-ground fauna.

  8. The first demonstration of lactic acid in human blood in shock by Johann Joseph Scherer (1814–1869) in January 1843

    PubMed Central

    Jansen, T. C.; van der Hoven, B.; Bakker, J.

    2007-01-01

    Lactic acid was first found and described in sour milk by Karl Wilhelm Scheele (1742–1786) in 1780. The German physician–chemist Johann Joseph Scherer (1841–1869) demonstrated the occurrence of lactic acid in human blood under pathological conditions in 1843 and 1851. In this article we honour the forgotten observations by Scherer and describe the influence of Scherer's finding on further research on lactic acid at the end of the 19th century. We conclude that Scherer's 1843 case reports should be cited as the first description of lactic acid in human blood after death and also as the first demonstration of lactic acid as a pathological finding in septic and haemorrhagic shock. Carl Folwarczny was, in 1858, the first to demonstrate lactic acid in blood in a living patient. PMID:17661014

  9. [Conception of the history of science in the interpretation of Bogdan Suchodolski].

    PubMed

    Lietz, Natalia

    2011-01-01

    In the article is presented the conception of the history of science in the interpretation of Bogdan Suchodolski. Having described the conception of the history of science created by George Sarton (1884-1956), whose thought was influenced by positivistic philosophy of August Comte, the idea of the history of science of Johan Nordstr6m (1891-1967), who was inspired by the system of Wilhelm Dilthey, and the materialistic conception of the history of science, which was represented, among others, by John Desmond Bernal (1901-1971), the author is making an attempt at revealing to what extent Bogdan Suchodolski was inspired by the above-mentioned visions of the history of science. Having defined the history of science as the history of scientific activity of people and their consciousness formed by the activity, Bogdan Suchodolski applied in the field of his own conception of the history of science the ideas that were put forward by German thinkers and philosophers, and were connected with a way of understanding culture as the constant development of national awareness, which can be exemplified with different dimensions of culture. Undoubtedly, identifying the history of Polish science with constitutive element of the history of national culture and paying attention to the conceptions tending not only to explaining, but also understanding phenomena, B. Suchodolski was influenced by Alfred Vierkandt's and Wilhelm Dilthey's thought. The present article includes several reflections on the conception of the history of science, which was created by B. Suchodolski. Among others, we can find here detailed information on how B. Suchodolski understood: the history of science, its subject, aim and methodology; its status in modern social consciousness and as the history of truth; relations between history of science and theory of science and scientific policy, history of science and the problem of unity and diversity of scientific thinking, history of science and ideas, history of culture and technology, and sources of scientific progress. PMID:21675045

  10. The I Ching and the psyche-body connection.

    PubMed

    Ma, Shirley S Y

    2005-04-01

    Carl G. Jung's fateful meeting with Richard Wilhelm in 1929 has helped to build a bridge of depth psychological understanding between the East and the West. When Jung emerged from his 'confrontation with the unconscious', he felt validated by Wilhelm in his discovery of the healing power of medieval alchemical symbolism for the European psyche. Analytical psychology however offers a scientific, psychological understanding of Chinese wisdom as contained in the I Ching and Taoist alchemy. The Taoist alchemical tradition (also known as the Inner Elixir tradition of which 'The Secret of the Golden Flower' is a sample text) is based on the premise that psychological experience of the Tao can be achieved through mental and physiological means such as breathing and meditative techniques, gymnastics, dietary regimens such as fasting, consumption of medicinal herbs and minerals, and special sexual practices. This tradition incorporates the I Ching and traditional Chinese medicine in the alchemical opus. Taoist alchemy assumes the primacy of the physical body in the process of self-realization. The psychological and cosmic forces of the trigrams of the I Ching are stored in the internal organs of the body and are the basic material for the experience of Tao. The internal organs are the foundation of the material and subtle bodies and through cultivation, the body becomes spiritualized as the spirits are embodied. The body as a reflection of the entire cosmos becomes the residence of the gods. The realization of a new consciousness is symbolized by the hexagram Fu, meaning rebirth. The Chinese notion of Tao coincides with Jung's postulation of the unus mundus, the unity of existence which underlies the duality of psyche and matter, the psycho-physical background of existence. In this light, in the world of inner experience, East and West follow similar paths symbolically. PMID:15817045

  11. Lunar Impact Basins: Stratigraphy, Sequence and Ages from Superposed Impact Crater Populations Measured from Lunar Orbiter Laser Altimeter (LOLA) Data

    NASA Technical Reports Server (NTRS)

    Fassett, C. I.; Head, J. W.; Kadish, S. J.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2012-01-01

    Impact basin formation is a fundamental process in the evolution of the Moon and records the history of impactors in the early solar system. In order to assess the stratigraphy, sequence, and ages of impact basins and the impactor population as a function of time, we have used topography from the Lunar Orbiter Laser Altimeter (LOLA) on the Lunar Reconnaissance Orbiter (LRO) to measure the superposed impact crater size-frequency distributions for 30 lunar basins (D = 300 km). These data generally support the widely used Wilhelms sequence of lunar basins, although we find significantly higher densities of superposed craters on many lunar basins than derived by Wilhelms (50% higher densities). Our data also provide new insight into the timing of the transition between distinct crater populations characteristic of ancient and young lunar terrains. The transition from a lunar impact flux dominated by Population 1 to Population 2 occurred before the mid-Nectarian. This is before the end of the period of rapid cratering, and potentially before the end of the hypothesized Late Heavy Bombardment. LOLA-derived crater densities also suggest that many Pre-Nectarian basins, such as South Pole-Aitken, have been cratered to saturation equilibrium. Finally, both crater counts and stratigraphic observations based on LOLA data are applicable to specific basin stratigraphic problems of interest; for example, using these data, we suggest that Serenitatis is older than Nectaris, and Humboldtianum is younger than Crisium. Sample return missions to specific basins can anchor these measurements to a Pre-Imbrian absolute chronology.

  12. Jung, Evans-Wentz and various other gurus.

    PubMed

    McGuire, William

    2003-09-01

    How did Jung become deeply concerned with Asian religions and particularly with the Tibetan Buddhism of a Welshman from Trenton, New Jersey? Could that man be considered one of Jung's gurus? This essay begins six years after Jung, at twenty, was admitted to the medical school of Basel University and became a member of the Zofingiaverein, a student society. The next year he gave the first of a series of lectures on the interpretation of Christ as the model of the 'god-man', like the Apostle Paul, Confucius, Zoroaster and the Buddha, who was 'drummed into the Hindu boy'. (Jung's Zofingia Lectures were discovered only after his death, in 1961, and were published in English in 1983). The present essay discusses Jung's early Buddhist interest as displayed in The Psychology of the Unconscious (finally, in a revision, entitled Symbols of Transformation), in Psychological Types and later in his foreword of the Wilhelm translation of the I Ching. Jung was influenced by the gurus Richard Wilhelm and his son Hellmut, the scholar J. W. Hauer (with whom he later broke off relations because of Hauer's Nazi politics), the indologist Heinrich Zimmer, and the Zen master D. T. Suzuki. Walter Yeeling Wentz was born in Trenton in 1878 and brought up in his family's theosophist faith. The Wentzes moved to San Diego in 1900, and Walter added his mother's Celtic surname, Evans, to the German Wentz. He was educated at Stanford University and travelled in Europe, studying Celtic folklore, and widely in the Near East, Tibet, India, and Oxford--studying religions everywhere and editing Tibetan books. He lived his last decades in San Diego and conducted a correspondence with Jung, while living in a cheap hotel, or in an ashram. PMID:14513477

  13. Innovative Conditioning Procedures for the Generation of Radioactive Waste Products which are Stable for Intermediate Storage or Repository-Independent in Final Storage

    SciTech Connect

    Steinmetz, H.J.; Heimbach, H.; Odoj, R.; Pruesse, R.; Wartenberg, W.

    2006-07-01

    The German Federal Government aims at a future final storage site for all kinds of radioactive waste within 30 years. Existing and newly-produced radioactive waste therefore has to be stored in interim storage facilities over very long periods of time. At present, most German radioactive waste or waste packages are produced and qualified according to the acceptance criteria of the projected final repository KONRAD. [1] Nevertheless, conditioning strategies for crude radioactive waste have to take into account the open question of the future repository site as well as requirements for long-term interim storage. The Quality Control Group for Radioactive Waste (in German: Produktkontrollstelle fuer radioaktive Abfaelle - PKS) works as an independent expert organisation for the quality checking of radioactive waste packages as well as evaluating conditioning procedures for waste containers suitable for final storage on behalf of the Federal Office for Radiation Protection (in German: Bundesamt fuer Strahlenschutz - BfS). The Institute for Safety Research and Reactor Technology (in German: Institut fuer Sicherheitsforschung and Reaktortechnik - ISR) of the Research Centre Juelich investigates scientific/technical problems of nuclear disposal, especially in the field of waste treatment. In this context, ISR and PKS investigated and/or evaluated innovative procedures, by means of which radioactive waste flows may be minimized and rendered inert. QSA Global (formerly: AEA Technology QSA) conditions radioactive waste of German users from the fields of medicine, research and industry as well as from its own radioactive source production and operates an intermediate storage facility for radioactive waste containers. This poster deals with the characteristics and possible applications of new waste fixation media on the basis of organic and inorganic mineral polymers; with the approach of producing inherently safe waste forms for various geological formations. Plasma technology and inorganic additives produce volume reduced glasses. Organic polymers evaluated are polysiloxane compounds with additives like barium sulfate, lead dioxide or others, depending on the specific requirements. As a counterpart to organic polymers, mineral polymers are based on silica and alumina, exhibiting better mechanical and thermal properties, as well as higher durability, compared with concrete. Thus QSA Global uses mineral polymers for packing radioactive waste containers, if high safety requirements have to be fulfilled like the waste acceptance criteria for the KONRAD repository. (Plasma products so far generated in experiments resemble natural obsidian, a highly inert and stable volcanic glass). (authors)

  14. Mechanistic modelling of Middle Eocene atmospheric carbon dioxide using fossil plant material

    NASA Astrophysics Data System (ADS)

    Grein, Michaela; Roth-Nebelsick, Anita; Wilde, Volker; Konrad, Wilfried; Utescher, Torsten

    2010-05-01

    Various proxies (such as pedogenic carbonates, boron isotopes or phytoplankton) and geochemical models were applied in order to reconstruct palaeoatmospheric carbon dioxide, partially providing conflicting results. Another promising proxy is the frequency of stomata (pores on the leaf surface used for gaseous exchange). In this project, fossil plant material from the Messel Pit (Hesse, Germany) is used to reconstruct atmospheric carbon dioxide concentration in the Middle Eocene by analyzing stomatal density. We applied the novel mechanistic-theoretical approach of Konrad et al. (2008) which provides a quantitative derivation of the stomatal density response (number of stomata per leaf area) to varying atmospheric carbon dioxide concentration. The model couples 1) C3-photosynthesis, 2) the process of diffusion and 3) an optimisation principle providing maximum photosynthesis (via carbon dioxide uptake) and minimum water loss (via stomatal transpiration). These three sub-models also include data of the palaeoenvironment (temperature, water availability, wind velocity, atmospheric humidity, precipitation) and anatomy of leaf and stoma (depth, length and width of stomatal porus, thickness of assimilation tissue, leaf length). In order to calculate curves of stomatal density as a function of atmospheric carbon dioxide concentration, various biochemical parameters have to be borrowed from extant representatives. The necessary palaeoclimate data are reconstructed from the whole Messel flora using Leaf Margin Analysis (LMA) and the Coexistence Approach (CA). In order to obtain a significant result, we selected three species from which a large number of well-preserved leaves is available (at least 20 leaves per species). Palaeoclimate calculations for the Middle Eocene Messel Pit indicate a warm and humid climate with mean annual temperature of approximately 22°C, up to 2540 mm mean annual precipitation and the absence of extended periods of drought. Mean relative air humidity was probably rather high, up to 77%. The combined results of the three selected plant taxa indicate values for atmospheric carbon dioxide concentration between 700 and 1100 ppm (probably about 900 ppm). Reference: Konrad, W., Roth-Nebelsick, A., Grein, M. (2008). Modelling of stomatal density response to atmospheric CO2. Journal of Theoretical Biology 253(4): 638-658.

  15. The Texas High-Precision Radial-Velocity Program

    NASA Astrophysics Data System (ADS)

    Cochran, W. D.; Hatzes, A. P.

    The University of Texas program for the measurement of high precision stellar radial velocity variations has expanded considerably during the past few years, and now comprises four separate efforts: 1) The McDonald Observatory Planet Search (MOPS) program, using the coude spectrograph of the 2.7m Harlan Smith Telescope, now has eleven years of data. In addition to the companion to 16 Cygni B, several of the program stars are showing interesting variations, and may eventually be shown to have substellar companions. 2) The ESO Planet Search (ESOPS), using an I2 collaboration with Martin Kurster, Konrad Dennerl and Stefan Dobereiner, was the first high precision Southern Hemisphere radial velocity survey. This program now has accumulated five years of data on 37 target stars. Results on interesting objects, such as Proxima Centauri, will be shown. 3) In 1996 we started a search for substellar companions to Hyades dwarfs, using the Keck 1 HIRES spectrograph and I2 cell. The Hyades provide a homogeneous sample of stars formed at the same time with the same composition. The goal of this program is to determine the dependence of planet formation on the one remaining independent variable in the sample, the stellar mass. 4) The Hobby Eberly Telescope is now in the middle of its scientific commissioning. Its high resolution spectrograph will be installed in the fall of 1998. This queue scheduled telescope is an ideal facility to use for a detailed survey of a broad sample of stars in the solar neighborhood.

  16. Reconstruction of the mass distribution of galaxy clusters from the inversion of the thermal Sunyaev-Zel'dovich effect

    NASA Astrophysics Data System (ADS)

    Majer, C. L.; Meyer, S.; Konrad, S.; Sarli, E.; Bartelmann, M.

    2016-05-01

    This paper continues a series in which we intend to show how all observables of galaxy clusters can be combined to recover the two-dimensional, projected gravitational potential of individual clusters. Our goal is to develop a non-parametric algorithm for joint cluster reconstruction taking all cluster observables into account. For this reason we focus on the line-of-sight projected gravitational potential, proportional to the lensing potential, in order to extend existing reconstruction algorithms. In this paper, we begin with the relation between the Compton-y parameter and the Newtonian gravitational potential, assuming hydrostatic equilibrium and a polytropic stratification of the intracluster gas. Extending our first publication (Konrad et al. 2013) we now consider a spheroidal rather than a spherical cluster symmetry. We show how a Richardson-Lucy deconvolution can be used to convert the intensity change of the CMB due to the thermal Sunyaev-Zel'dovich effect into an estimate for the two-dimensional gravitational potential. We apply our reconstruction method to a cluster based on an N-body/hydrodynamical simulation processed with the characteristics (resolution and noise) of the ALMA interferometer for which we achieve a relative error of ≲ 20 per cent for a large fraction of the virial radius. We further apply our method to an observation of the galaxy cluster RXJ1347 for which we can reconstruct the potential with a relative error of ≲ 20 per cent for the observable cluster range.

  17. Reconstruction of palaeoatmospheric carbon dioxide using stomatal densities of various beech plants (Fagaceae): testing and application of a mechanistic model

    NASA Astrophysics Data System (ADS)

    Grein, M.; Roth-Nebelsick, A.; Konrad, W.

    2006-12-01

    A mechanistic model (Konrad &Roth-Nebelsick a, in prep.) was applied for the reconstruction of atmospheric carbon dioxide using stomatal densities and photosynthesis parameters of extant and fossil Fagaceae. The model is based on an approach which couples diffusion and the biochemical process of photosynthesis. Atmospheric CO2 is calculated on the basis of stomatal diffusion and photosynthesis parameters of the considered taxa. The considered species include the castanoid Castanea sativa, two quercoids Quercus petraea and Quercus rhenana and an intermediate species Eotrigonobalanus furcinervis. In the case of Quercus petraea literature data were used. Stomatal data of Eotrigonobalanus furcinervis, Quercus rhenana and Castanea sativa were determined by the authors. Data of the extant Castanea sativa were collected by applying a peeling method and by counting of stomatal densities on the digitalized images of the peels. Additionally, isotope data of leaf samples of Castanea sativa were determined to estimate the ratio of intercellular to ambient carbon dioxide. The CO2 values calculated by the model (on the basis of stomatal data and measured or estimated biochemical parameters) are in good agreement with literature data, with the exception of the Late Eocene. The results thus demonstrate that the applied approach is principally suitable for reconstructing palaeoatmospheric CO2.

  18. Baby Schema in Infant Faces Induces Cuteness Perception and Motivation for Caretaking in Adults

    PubMed Central

    Glocker, Melanie L.; Langleben, Daniel D.; Ruparel, Kosha; Loughead, James W.; Gur, Ruben C.; Sachser, Norbert

    2012-01-01

    Ethologist Konrad Lorenz proposed that baby schema (‘Kindchenschema’) is a set of infantile physical features such as the large head, round face and big eyes that is perceived as cute and motivates caretaking behavior in other individuals, with the evolutionary function of enhancing offspring survival. Previous work on this fundamental concept was restricted to schematic baby representations or correlative approaches. Here, we experimentally tested the effects of baby schema on the perception of cuteness and the motivation for caretaking using photographs of infant faces. Employing quantitative techniques, we parametrically manipulated the baby schema content to produce infant faces with high (e.g. round face and high forehead), and low (e. g. narrow face and low forehead) baby schema features that retained all the characteristics of a photographic portrait. Undergraduate students (n = 122) rated these infants’ cuteness and their motivation to take care of them. The high baby schema infants were rated as more cute and elicited stronger motivation for caretaking than the unmanipulated and the low baby schema infants. This is the first experimental proof of the baby schema effects in actual infant faces. Our findings indicate that the baby schema response is a critical function of human social cognition that may be the basis of caregiving and have implications for infant–caretaker interactions. PMID:22267884

  19. The challenge of reducing scientific complexity for different target groups (without losing the essence) - experiences from interdisciplinary audio-visual media production

    NASA Astrophysics Data System (ADS)

    Hezel, Bernd; Broschkowski, Ephraim; Kropp, Jürgen

    2013-04-01

    The Climate Media Factory originates from an interdisciplinary media lab run by the Film and Television University "Konrad Wolf" Potsdam-Babelsberg (HFF) and the Potsdam Institute for Climate Impact Research (PIK). Climate scientists, authors, producers and media scholars work together to develop media products on climate change and sustainability. We strive towards communicating scientific content via different media platforms reconciling the communication needs of scientists and the audience's need to understand the complexity of topics that are relevant in their everyday life. By presenting four audio-visual examples, that have been designed for very different target groups, we show (i) the interdisciplinary challenges during the production process and the lessons learnt and (ii) possibilities to reach the required degree of simplification without the need for dumbing down the content. "We know enough about climate change" is a short animated film that was produced for the German Agency for International Cooperation (GIZ) for training programs and conferences on adaptation in the target countries including Indonesia, Tunisia and Mexico. "Earthbook" is a short animation produced for "The Year of Science" to raise awareness for the topics of sustainability among digital natives. "What is Climate Engineering?". Produced for the Institute for Advanced Sustainability Studies (IASS) the film is meant for an informed and interested public. "Wimmelwelt Energie!" is a prototype of an iPad application for children from 4-6 years of age to help them learn about different forms of energy and related greenhouse gas emissions.

  20. Recent international developments in low-level waste disposal

    SciTech Connect

    Mitchell, S.J.; Lakey, L.T.; Harmon, K.M.

    1986-11-01

    Recent international developments in low-level waste (LLW) disposal have included a move away from ocean dumping and a trend towards engineered and deeper dispoosal. Siting efforts have accelerated as interim storage facilities and existing sites reach capacity. The suspension of ocean dumping by the London Dumping Conventions of 1983 and 1985 has affected the LLW disposal practices of several countries, including the United Kingdom, Belgium, the Netherlands, Switzerland, and Japan. Their plans now include disposal in trenches, shallow concrete pits, deep mines, sub-seabed caverns, horizontal mountain tunnels, and long-term storage facilities. Other recent developments include selection of the semi-desert Vaalputs site in South Africa, licensing activities for the Konrad mine site in the Federal Republic of Germany, design of at-reactor sites in Finland, and construction of a Baltic Sea site in Sweden. Also, the French have recently selected the Aube site for engineered disposal in monoliths and tumuli, now used at the La Manche site.

  1. Patients with Obstructive Sleep Apnea at Altitude.

    PubMed

    Bloch, Konrad E; Latshang, Tsogyal D; Ulrich, Silvia

    2015-06-01

    Bloch, Konrad E., Tsogyal D. Latshang, and Silvia Ulrich. Patients with obstructive sleep apnea at altitude. High Alt Med Biol 16:110-116, 2015.--Obstructive sleep apnea (OSA) is highly prevalent in the general population, in particular in men and women of older age. In OSA patients sleeping near sea level, the apneas/hypopneas associated with intermittent hypoxemia are predominantly due to upper airway collapse. When OSA patients stay at altitudes above 1600 m, corresponding to that of many tourist destinations, hypobaric hypoxia promotes frequent central apneas in addition to obstructive events, resulting in combined intermittent and sustained hypoxia. This induces strong sympathetic activation with elevated heart rate, cardiac arrhythmia, and systemic hypertension. There are concerns that these changes expose susceptible OSA patients, in particular those with advanced age and co-morbidities, to an excessive risk of cardiovascular and other adverse events during a stay at altitude. Based on data from randomized trials, it seems advisable for OSA patients to use continuous positive airway pressure treatment with computer controlled mask pressure adjustment (autoCPAP) in combination with acetazolamide during an altitude sojourn. If CPAP therapy is not feasible, acetazolamide alone is better than no treatment at all, as it improves oxygenation and sleep apnea and prevents excessive blood pressure rises of OSA patients at altitude. PMID:25973669

  2. Organisms in their milieu: Alfred Giard, his pupils, and early ethology, 1870-1930.

    PubMed

    De Bont, Raf

    2010-03-01

    This essay tells the story of early French ethology--"the science dealing with the habits of living beings and their relations, both with each other and with the cosmic environment." The driving force behind this "ethological movement" was the biologist Alfred Giard (1846-1908). The essay discusses how the ethological viewpoint of Giard and his pupils developed in a period in which the current disciplines of field biology were not yet crystallized. It also shows how concepts and research interests could travel within Giard's network from one working context to another, even from one discipline to another. By studying this traveling process, the essay reveals that, unlike the modern ethology of Konrad Lorenz and Niko Tinbergen, Giard's ethology was not a discipline at all but, rather, a scientific attitude. This scientific attitude triggered a reappraisal of fieldwork, but at the same time Giard's ethology was never limited to the field alone. It also found its way to the laboratory, the museum, and the zoo. PMID:20575488

  3. [Peace policy by accusations of heresy against Johannes Crato (1519-1585) and denunciation of Paracelcius followers as Arians].

    PubMed

    Bröer, Ralf

    2002-01-01

    Since 1563 the Paracelsians were publicly denounced as Arians who denied the full divinity of Christ. A work of Alexander von Suchten, who was personal physician of the Polish King, triggered the polemic. The "Propositiones" of Suchten outlined a doctrine of salvation based on chemistry and medicine. As can be proved the pamphlet was influenced by heterodox christologies and doctrines of justification. But there are no indications of contacts between Suchten and Polish antitrinitarians of his time. Actually the public denunciation of the Paracelsians as Arians was a clever political move of the Emperor's personal physician Johannes Crato who aimed at the reformation of medicine in a humanistic sense. This aim was threatened by the fundamental opposition of the Paracelsians, exactly as his irenic religious policy was jeopardized by the growing confessional dogmatism. In this situation Crato used the instrument of denunciation as a means to dissociate himself from medical and theological extremists. The Zurich naturalist Konrad Gessner supplied him with the basic idea. Thomas Erastus, medical professor in Heidelberg, worked out the accusation in detail. PMID:12522916

  4. “Advice to the medical students in my service”: the rediscovery of a golden book by Jean Hamburger, father of nephrology and of medical humanities

    PubMed Central

    2013-01-01

    Jean Hamburger (1909–1992) is considered the founder of the concept of medical intensive care (réanimation médicale) and the first to propose the name Nephrology for the branch of medicine dealing with kidney diseases. One of the first kidney grafts in the world (with short-term success), in 1953, and the first dialysis session in France, in 1955, were performed under his guidance. His achievements as a writer were at least comparable: Hamburger was awarded several important literary prizes, including prix Femina, prix Balzac and the Cino del Duca prize (1979), awarded, among others, to Jorge Luis Borges and Konrad Lorenz. Here we would like to offer a selected reading of a “golden” book, “Conseils aux étudiants en medicine de mon service” (“Advice to the Medical Students in my Service”), the first book dedicated to patient-physician relationship in Nephrology, written when dialysis and transplantation were becoming clinical options (1963). The themes include: the central role of the patient, who should be known by name, profession, life style, and not by disease; the importance of the setting of the care; the need for truth-telling and for leaving hope; the role of research not only in the progression of science, but also in the daily clinical practice. PMID:23497662

  5. "Advice to the medical students in my service": the rediscovery of a golden book by Jean Hamburger, father of nephrology and of medical humanities.

    PubMed

    Barbara, Piccoli Giorgina

    2013-01-01

    Jean Hamburger (1909-1992) is considered the founder of the concept of medical intensive care (réanimation médicale) and the first to propose the name Nephrology for the branch of medicine dealing with kidney diseases. One of the first kidney grafts in the world (with short-term success), in 1953, and the first dialysis session in France, in 1955, were performed under his guidance. His achievements as a writer were at least comparable: Hamburger was awarded several important literary prizes, including prix Femina, prix Balzac and the Cino del Duca prize (1979), awarded, among others, to Jorge Luis Borges and Konrad Lorenz.Here we would like to offer a selected reading of a "golden" book, "Conseils aux étudiants en medicine de mon service" ("Advice to the Medical Students in my Service"), the first book dedicated to patient-physician relationship in Nephrology, written when dialysis and transplantation were becoming clinical options (1963). The themes include: the central role of the patient, who should be known by name, profession, life style, and not by disease; the importance of the setting of the care; the need for truth-telling and for leaving hope; the role of research not only in the progression of science, but also in the daily clinical practice. PMID:23497662

  6. Geospatial assessment of ecological functions and flood-related risks on floodplains along major rivers in the Puget Sound Basin, Washington

    USGS Publications Warehouse

    Konrad, Christopher P.

    2015-01-01

    Ecological functions and flood-related risks were assessed for floodplains along the 17 major rivers flowing into Puget Sound Basin, Washington. The assessment addresses five ecological functions, five components of flood-related risks at two spatial resolutions—fine and coarse. The fine-resolution assessment compiled spatial attributes of floodplains from existing, publically available sources and integrated the attributes into 10-meter rasters for each function, hazard, or exposure. The raster values generally represent different types of floodplains with regard to each function, hazard, or exposure rather than the degree of function, hazard, or exposure. The coarse-resolution assessment tabulates attributes from the fine-resolution assessment for larger floodplain units, which are floodplains associated with 0.1 to 21-kilometer long segments of major rivers. The coarse-resolution assessment also derives indices that can be used to compare function or risk among different floodplain units and to develop normative (based on observed distributions) standards. The products of the assessment are available online as geospatial datasets (Konrad, 2015; http://dx.doi.org/10.5066/F7DR2SJC).

  7. From lanosterol to cholesterol: structural evolution and differential effects on lipid bilayers.

    PubMed

    Miao, Ling; Nielsen, Morten; Thewalt, Jenifer; Ipsen, John H; Bloom, Myer; Zuckermann, Martin J; Mouritsen, Ole G

    2002-03-01

    Cholesterol is an important molecular component of the plasma membranes of mammalian cells. Its precursor in the sterol biosynthetic pathway, lanosterol, has been argued by Konrad Bloch (Bloch, K. 1965. Science. 150:19-28; 1983. CRC Crit. Rev. Biochem. 14:47-92; 1994. Blonds in Venetian Paintings, the Nine-Banded Armadillo, and Other Essays in Biochemistry. Yale University Press, New Haven, CT.) to also be a precursor in the molecular evolution of cholesterol. We present a comparative study of the effects of cholesterol and lanosterol on molecular conformational order and phase equilibria of lipid-bilayer membranes. By using deuterium NMR spectroscopy on multilamellar lipid-sterol systems in combination with Monte Carlo simulations of microscopic models of lipid-sterol interactions, we demonstrate that the evolution in the molecular chemistry from lanosterol to cholesterol is manifested in the model lipid-sterol membranes by an increase in the ability of the sterols to promote and stabilize a particular membrane phase, the liquid-ordered phase, and to induce collective order in the acyl-chain conformations of lipid molecules. We also discuss the biological relevance of our results, in particular in the context of membrane domains and rafts. PMID:11867458

  8. [Sheehan's syndrome--a forgotten disease with 100 years' history].

    PubMed

    Krysiak, Robert; Okopień, Bogusław

    2015-01-01

    Although named after Harold Sheehan, postpartum ischemic pituitary necrosis was reported for the first time 100 years ago in Przeglad Lekarski by Leon Konrad Gliński. In the majority of cases, the syndrome is a consequence of severe postpartum bleeding episode resulting in severe hypotension or hemorrhagic shock. The frequency of Sheehan's syndrome has decreased in developed countries as a result of improved obstetrical care, but this clinical entity remains a common cause of hypopituitarism in developing countries. The syndrome is characterized by varying degrees of anterior pituitary dysfunction resulting from the deficiency of multiple pituitary hormones. The order of frequency of hormone loss has generally been found to be growth hormone and prolactin, gonadotropins, ACTH and thyrotropin. Women with Sheehan's syndrome exhibit a variety of signs and symptoms including failure to lactate or resume menses, loss of genital and axillary hair, and often occurring long after delivery clinical manifestations of central hypothyroidism and secondary adrenal insufficiency. Diagnosis is based on laboratory studies, including hormone levels and hormone stimulation tests. Treatment of Sheehan's syndrome involves hormone replacement therapy. The aim of this study is to review current knowledge on clinically relevant aspects of this clinical entity and to provide the reader with recommendations concerning its diagnosis and treatment. PMID:26817341

  9. Imaging shocked sapphire in the 20--40 GPa range: The effect of crystal orientation on optical emission

    NASA Astrophysics Data System (ADS)

    Hare, David E.; Holmes, N. C.

    1999-06-01

    We have taken short exposure gated images (<= 50ns) of 20--40 GPa shock loaded, single crystal sapphire windows of the c-cut (0001), r-cut (1,-1,0,2), and a-cut (1,1,-2,0) orientations. We find that the c-cut and a-cut windows show evidence of intense emission in randomly distributed localized regions, whereas the r-cut windows were remarkably free of this effect and showed sparse emission. We interpret this effect in terms of slip band heating as previously demonstrated for α-quartz (Shock-induced luminescence from x-cut quartz and z-cut lithium niobate, P.J. Brannon, R.W. Morris, C.H. Konrad and J.R. Asay, Shock waves in condensed matter - 1983), Asay, Graham, Straub eds., Elsevier Science Publishers 1984 and discuss the potential impact of these results on the usage of sapphire as a window for optical experiments on shock-loaded materials in which the Al_2O3 windows are shocked above the Hugoniot elastic limit.

  10. [An image of Saint Ottilia with reading stones].

    PubMed

    Daxecker, F; Broucek, A

    1995-01-01

    Reading stones to facilitate reading in cases of presbyopia are mentioned in the literature, for example in the works of the Middle High German poet Albrecht and of Konrad of Wrzburg. Most representations of the abbess, Saint Ottilia, show her holding a book with a pair of eyes in her hands. A gothic altarpiece (1485-1490), kept in the museum of the Premonstratensian Canons of Wilten in Innsbruck, Tyrol, shows a triune representation of St. Anne, the mother of the Virgin, with Mary and Jesus and St. Ursula with her companions. St. Ottilia is depicted on the edge of the painting. Two lenses, one on either side of the open book in her hand, magnify the letters underneath. As the two lenses are not held together by bows or similar devices, they are probably a rare representation of reading stones. The alter showing scenes of the life of St. Mary and St. Ursula was done by Ludwig Konraiter. A panel on the same alter, depicting the death of the Virgin, shows an apostle with rivet spectacles. PMID:8851062

  11. Nuclear Rocket Facility Decommissioning Project: Controlled Explosive Demolition of Neutron-Activated Shield Wall

    SciTech Connect

    Michael R. Kruzic

    2008-06-01

    Located in Area 25 of the Nevada Test Site (NTS), the Test Cell A (TCA) Facility (Figure 1) was used in the early to mid-1960s for testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program, to further space travel. Nuclear rocket testing resulted in the activation of materials around the reactors and the release of fission products and fuel particles. The TCA facility, known as Corrective Action Unit 115, was decontaminated and decommissioned (D&D) from December 2004 to July 2005 using the Streamlined Approach for Environmental Restoration (SAFER) process, under the Federal Facility Agreement and Consent Order. The SAFER process allows environmental remediation and facility closure activities (i.e., decommissioning) to occur simultaneously, provided technical decisions are made by an experienced decision maker within the site conceptual site model. Facility closure involved a seven-step decommissioning strategy. First, preliminary investigation activities were performed, including review of process knowledge documentation, targeted facility radiological and hazardous material surveys, concrete core drilling and analysis, shield wall radiological characterization, and discrete sampling, which proved to be very useful and cost-effective in subsequent decommissioning planning and execution and worker safety. Second, site setup and mobilization of equipment and personnel were completed. Third, early removal of hazardous materials, including asbestos, lead, cadmium, and oil, was performed ensuring worker safety during more invasive demolition activities. Process piping was to be verified void of contents. Electrical systems were de-energized and other systems were rendered free of residual energy. Fourth, areas of high radiological contamination were decontaminated using multiple methods. Contamination levels varied across the facility. Fixed beta/gamma contamination levels ranged up to 2 million disintegrations per minute (dpm)/100 centimeters squared (cm2) beta/gamma. Removable beta/gamma contamination levels seldom exceeded 1,000 dpm/100 cm2, but, in railroad trenches on the reactor pad containing soil on the concrete pad in front of the shield wall, the beta dose rates ranged up to 120 milli-roentgens per hour from radioactivity entrained in the soil. General area dose rates were less than 100 micro-roentgens per hour. Prior to demolition of the reactor shield wall, removable and fixed contaminated surfaces were decontaminated to the best extent possible, using traditional decontamination methods. Fifth, large sections of the remaining structures were demolished by mechanical and open-air controlled explosive demolition (CED). Mechanical demolition methods included the use of conventional demolition equipment for removal of three main buildings, an exhaust stack, and a mobile shed. The 5-foot (ft), 5-inch (in.) thick, neutron-activated reinforced concrete shield was demolished by CED, which had never been performed at the NTS.

  12. Holocene geological records of flood regime in French Alps

    NASA Astrophysics Data System (ADS)

    Arnaud, Fabien; Wilhelm, Bruno; Giguet-Covex, Charline; Jenny, Jean-Philippe; Fouinat, Laurent; Sabatier, Pierre; Debret, Maxime; Révillon, Sidonie; Chapron, Emmanuel; Revel, Marie

    2014-05-01

    In this paper we present a review of a ca. 10-years research effort (1-9) aiming at reconstructing floods dynamics in in French Alps through the Holocene, based on lake sediment records. We will particularly discuss how such geological records can be considered as representative of past climate. This implies a wise interpretation of data in order to really understand "what does the core really says". Namely, we showed that different lake systems record different types of flood events. Low altitude lakes, fed by large-scale catchment areas are more sensitive to regional heavy rainfall events (2-5), whereas high altitude small lakes record local extreme rainfall events (6). Moreover, human societies' development must be taken into account as it is susceptible to modulate the climate-geological record relationship (7). Altogether our data permit the establishment of a Holocene-long perspective upon both regional heavy rainfall and torrential activities in high elevation sites. We hence show that both types of events frequency co-evolve in Northern as well as Southern French Alps where Holocene colder spells generally present higher flood frequencies (6-9). On the other hand, intensities of torrential events present a North-South opposite pattern: during warm spells (e.g. the Medieval Warm Period or nowadays), northern Alps are subject to rare but extremely intense heavy rainfall events, whereas in the southern Alps torrential floods are both rare and weak. During cold spells (e.g. the Little Ice Age), the inverse pattern is observed: torrential floods are more frequent everywhere and above-average intensity in Southern Alps. This point is particularly important for risk management in mountain areas in a context of global warming. Our results point out how complex can be the response of regional system to global climate changes. We are hence far from completely understanding this complexity which is moreover imperfectly simulated by climate models. As geological records represent the only way to reconstruct long-term trends in flood regimes, more efforts must still be pursued to get a more complete image of this complexity and further improve climate models. 1. Chapron et al. The Holocene 12, 177-185 (2002) 2. Arnaud et al. Quat. Sci. Rev. 51, 81-92 (2012) 3. Debret et al. Quat. Sci. Rev. 29, 2185-2200 (2010) 4. Arnaud et al. The Holocene 15, 420-428 (2005) 5. Revel-Rolland et al. Chem. Geol. 224, 183-200 (2005) 6. Wilhelm et al. Clim. Change 113, 563-581 (2012) 7. Giguet-Covex et al. Quat. Res. 77, 12-22 (2012) 8. Wilhelm et al. Quat. Res. 78, 1-12 (2012) 9. Wilhelm et al. J. Quat. Sci. 28, 189-199 (2013)

  13. Investigation of Micro-mechanical Causes of Density Inversion in Polar Firn

    NASA Astrophysics Data System (ADS)

    Breton, D. J.; Keegan, K. M.; Albert, M. R.

    2011-12-01

    The densification of polar firn is a microstructure dependent process (Alley et al., 1982) which plays an important role both in interpretation of paleoclimate records in ice cores and in the remote sensing evaluation of ice sheet volume changes over time. Density inversion results from prolonged differential compaction rates between different microstructure types: low density, coarse grained firn (CGF) tends to compact faster than the high density, fine grained firn (FGF). Eventually, the relative density of the two firn types "inverts", that is, CGF becomes more dense than FGF at some depth (Gerland et al., 1999; Freitag et al., 2010). This process continues beyond the point where CGF and FGF densities are equal, suggesting that some parameter other than bulk density determines the densification rate (Hörhold et al, 2011). Recent work in granular physics (Phillippe et al., 2002; Richard et al., 2005 ; Ribière et al., 2007), have shown that particle size distribution, shape and friction play important roles in determining the both the maximum density of random close packed ensembles, and the magnitude of density difference between the initial state (random loose packed) and final state (random close packed) particle ensembles. We explore the consequences of these granular effects on the densification of polar firn using discrete element modeling of ice particle rearrangement mediated by grain boundary sliding processes (Alley, 1987). Because sintering rate is greatly reduced for pairs of large particles and particle pairs with large size differences (Colbeck, 2001), we expect that CGF will experience enhanced grain boundary sliding compared to the well bonded and highly coordinated particles in FGF. By simulating uni-axial compression on particle ensembles with varying size, shape and frictional properties, we hope to demonstrate that CGF densifies faster than FGF via enhanced grain boundary sliding, and can achieve a higher final density than FGF at the end of particle rearrangment due to the aspherical shape of CGF particles. REFERENCES - Alley, R., Firn densification by grain-boundary sliding: a first model, J. Phys. Coll., 1987, 48, p. 249-256. - Alley, R., Bolzan, J. & Whillans, I., Polar firn densification and grain growth, Ann. Glac., 1982, 3, p. 7-11. - Colbeck, S.C., Sintering of unequal grains, J. Appl. Phys., 2001, 89, p. 4612. - Freitag, J., Wilhelms, F. & Kipfstuhl, S., Microstructure-dependent densification of polar firn derived from X-ray microtomography, J. Glac., 2004, 50, p. 243-250. - Gerland, S., Oerter, H.; Kipfstuhl, J.; Wilhelms, F.; Miller, H. & Miners, W., Density log of a 181 m long ice core from Berkner Island, Antarctica, Ann. Glac., 1999, 29, p. 215-219. - Hörhold, M., Kipfstuhl, S.; Wilhelms, F.; Freitag, J. & Frenzel, A., The densification of layered polar firn, J. Geophys. Res., 2011, 116, F01001. - Philippe, P. & Bideau, D., Compaction dynamics of a granular medium under vertical tapping, Europhys. Lett., 2002, 60, p. 677. - Ribière, P., Richard, P., Bideau, D., Delannay, R.: Experimental compaction of anisotropic granular media. Euro. Phys. J. E, 2005, 16, p. 415-420. - Richard, P., Nicodemi, M.; Delannay, R.; Ribière, P. & Bideau, D., Slow relaxation and compaction of granular systems, Nat. Mat., 2005, 4, p. 121-128.

  14. Foreword

    NASA Astrophysics Data System (ADS)

    Farle, Michael; Wende, Heiko; Arvanitis, Dimitri

    2003-02-01

    Photograph of Participants Many magnetic phenomena in nanoscale structures are strongly influenced by the interaction of orbital magnetic moments and spin moments. For example, anisotropic magnetoresistance, magnetostriction, the magnitude and anisotropy of magnetic moments, and the overall magnetic anisotropy energy of ferromagnets are intrinsically related to this interaction. In today's low dimensional magnetic structures, spin-orbit influenced phenomena become even more important, since the well known quenching of the orbital magnetic momentum encountered in bulk systems is lifted. Furthermore, magnetic systems may be prepared with highly strained crystallographic structures in phases that do not occur naturally in the bulk. In order to characterize the real space and magnetic structure of such novel low dimensional magnets, x-ray, neutron and electron based techniques are commonly used. Very often discrepancies are found in the results not only with theory but also between various experimental probes, highlighting the difficulty of the problem and the need for a comprehensive dialogue between experimentalists and theoreticians. The purpose of this 281 Wilhelm und Else Heraeus Seminar was the gathering of leading experts from different fields of solid state physics to discuss the different approaches of calculating and measuring spin-orbit influenced phenomena in magnetic low dimensional systems and nanostructures. 70 participants from Germany, France, Italy, Japan, Poland, Romania, Sweden, Ukraine and the USA attended the four day workshop and heard 24 invited lectures and saw 35 poster presentations. The results of the lectures and lively discussions which ended often late at night are summarized in the contributions to this special volume. We feel that the authors have accomplished the difficult task of combining a tutorial type of introduction to their specific research area with an excellent presentation of their latest results. The interested reader will find contributions discussing the results obtained by a rich variety of experimental techniques such as photoemission, magnetic and natural x-ray dichroism, paramagnetic and ferromagnetic resonance, neutron scattering and reflectometry, magneto-optics and femtosecond spectroscopy. The numerous experimental results covering aspects of the g-tensor analysis in magnetic monolayers, exchange-coupling, spin-orbit splitting in electronic band structure and excited crystal field states were complemented by state of the art theoretical presentations of, for example, the magnetic susceptibility and orbital and spin magnetic moments obtained from ab-initio calculations. We would like to thank the authors for their excellent contributions and the chairpersons and participants for making the 281 Wilhelm und Else Heraeus Seminar such a high-level event in terms of scientific output and lively interactions.

  15. Historical perspective on developmental concepts and terminology.

    PubMed

    Opitz, John M; Neri, Giovanni

    2013-11-01

    In their ontogeny and phylogeny all living beings are historical entities. The revolution in biology of the 18th and 19th centuries that did away with the scala naturae according to which we humans, the acme of creation, "made a little lower than the angels," also led to the gradual realization that a humble one-celled protist ("protoctist"), such as Entamoeba histolytica of ill repute [Margulis and Chapman, ] has the same 4-billion-year phylogeny as that of Homo sapiens, vivid testimony to common ancestry and the relatedness of all living beings on earth. The group of medical geneticists who assembled at the NIH, Bethesda, MD this January to address terms pertaining to human ontogeny, did so in the long tradition of Sydenham, Linnaeus, Meckel, Geoffroy St-Hilaire père et fils, Wilhelm His and so many others before who had over the previous two centuries wrestled as earnestly as they could with concepts of "classification" and nomenclature of developmental anomalies. The prior massive need for classification per se in medical morphology has diminished over the years in favor of ever more sophisticated understanding of pathogenesis and cause through experimental biology and genetics; however, in the winter of 2013 it was still found prudent to respect terminological precedent on general terms while recognizing recent advances in developmental pathology requiring clarification and definition of special terms. Efforts along similar lines instigated by the German Society of Anatomists at their first meeting in Leipzig in 1887 culminated, after intense years of work by hundreds of experts and consultants under the goad of Wilhelm His, in the Basel Nomina Anatomica [BNA, His (1895)]. His, himself, stated prefatorily that the BNA had no legislative weight, only an evanescent consensus of many to be amended in the future as needed and indicated. Without hubris, no one before or after will do the same. The more substantial the consensus the more permanent the structure. After some 120 years the BNA is alive and flourishing. Now retitled Terminologia Anatomica, it has been amended and added to many times, is still in Latin but now with synonyms in English, the new lingua franca of science, for every anatomical, histological and embryological term. May our successors be equally effective. PMID:24123982

  16. Paperless or vanishing society

    NASA Astrophysics Data System (ADS)

    Turner Luke, Joy

    2002-06-01

    In the 1940s color photography became available and within a few years, extremely popular. As people switched from black and white photographs made with the old metallic silver process to the new color films, pictures taken to record their lives and families began a slow disappearing act. The various color processes, coupled with the substrates they were printed on, affected their longevity, but many color photographs taken from the late 1950s through the 1970s, and even into the 1980s, faded not only when exposed to the light, but also when stored in the dark. Henry Wilhelm's excellent book 'The Permanence and Care of Color Photographs' documents this history in detail. Today we are making another transition in the storage of pictures and information. There are questions about the longevity of different types of digital storage, and also of the images printed by various types of inkjet printers, or by laser printers using colored toners. Very expensive and very beautiful works of art produced on Iris printers are appearing in art exhibitions. Some of these are referred to as Giclee prints and are offered on excellent papers. Artists are told the prints will last a lifetime; and if by change they don't it is only necessary to make another print. Henry Wilhelm has begun to test and rate these images for lightfastness; however, his test method was developed for examining longevity in colored photographs. It is of interest to find out how these prints will hold up in the tests required for fine art materials. Thus far companies producing digital inks and printers have not invested the time and money necessary to develop an American Society for Testing and Materials (ASTM) standard method for evaluating the lightfastness of digital prints. However, it is possible to use ASTM D 5383, Standard Practice for Visual Determination of the Lightfastness of Art Materials by Art Technologists, to pinpoint colors that will fade in a short time, even though the test is not as severe as ASTM D 4303, which is used to rate the lightfastness of artists's paint.

  17. Solar gamma-ray spectrometer GRIS onboard the International Space Station

    NASA Astrophysics Data System (ADS)

    Kotov, Yu. D.; Yurov, V. N.; Trofimov, Yu. A.; Lupar, E. E.; Glyanenko, A. S.; Faradzhaev, R. M.

    2015-10-01

    GRIS (Gamma and Roentgen Irradiation of the Sun) is a scientific instrument for detection of hard X-rays and gamma-rays of solar flares with the energies from 50 keV to 200 MeV and for registration of solar neutrons with energies above 30 MeV. The experiment will be performed since 2019 onboard the International Space Station. The instrument includes two spectrometers: the low energy spectrometer based on a fast scintillator with high energy resolution 3.5-4.5% at 662 keV (LaBr3(Ce) or CeBr3) and dimensions ø7.62 × 7.62 cm, and the high energy spectrometer based on CsI(Tl) scintillator ø12 × 15 cm (which is also intended for neutron registration). The apparatus will be mounted on the oriented platform outside the Zvezda service module in 2019. Simulated response of the detectors to background radiation and to solar flares of different magnitudes and compositions obtained with GEANT4 toolkit confirms the instrument's possibility to measure different components of the solar flares spectra: narrow gamma lines, pion decay component, etc. with a sufficient confidence due to the usage of two types of detectors.

  18. Prospective five-year subsidence analysis of a cementless fully hydroxyapatite-coated femoral hip arthroplasty component.

    PubMed

    Clauss, Martin; Van Der Straeten, Catherine; Goossens, Marc

    2014-01-01

    Early subsidence >1.5 mm is considered to be a predictive factor for later aseptic loosening of the femoral component following total hip arthroplasty (THA). The aim of this study was to assess five-year subsidence rates of the cementless hydroxyapatite-coated twinSys stem (Mathys Ltd., Bettlach, Switzerland).This prospective single-surgeon series examined consecutive patients receiving a twinSys stem at Maria Middelares Hospital, Belgium. Patients aged >85 years or unable to come to follow-up were excluded. Subsidence was assessed using Ein Bild Roentgen Analyse--Femoral Component Analysis (EBRA-FCA). Additional clinical and radiographic assessments were performed. Follow-ups were prospectively scheduled at two, five, 12, 24, and 60 months.In total, 218 THA (211 patients) were included. At five years, mean subsidence was 0.66 mm (95% CI: 0.43-0.90). Of the 211 patients, 95.2% had an excellent or good Harris Hip Score. There were few radiological changes. Kaplan-Meier analysis indicated five-year stem survival to be 98.4% (95% CI: 97.6-100%).Subsidence levels of the twinSys femoral stem throughout the five years of follow-up were substantially lower than the 1.5 mm level predictive of aseptic loosening. This was reflected in the high five-year survival rate. PMID:24474406

  19. Image-assisted non-invasive and dynamic biomechanical analysis of human joints

    NASA Astrophysics Data System (ADS)

    Muhit, Abdullah A.; Pickering, Mark R.; Scarvell, Jennifer M.; Ward, Tom; Smith, Paul N.

    2013-07-01

    Kinematic analysis provides a strong link between musculoskeletal injuries, chronic joint conditions, treatment planning/monitoring and prosthesis design/outcome. However, fast and accurate 3D kinematic analysis still remains a challenge in order to translate this procedure into clinical scenarios. 3D computed tomography (CT) to 2D single-plane fluoroscopy registration is a promising non-invasive technology for biomechanical examination of human joints. Although this technique has proven to be very precise in terms of in-plane translation and rotation measurements, out-of-plane motion estimations have been a difficulty so far. Therefore, to enable this technology into clinical translation, precise and fast estimation of both in-plane and out-of-plane movements is crucial, which is the aim of this paper. Here, a fast and accurate 3D/2D registration technique is proposed to evaluate biomechanical/kinematic analysis. The proposed algorithm utilizes a new multi-modal similarity measure called ‘sum of conditional variances’, a coarse-to-fine Laplacian of Gaussian filtering approach for robust gradient-descent optimization and a novel technique for the analytic calculation of the required gradients for out-of-plane rotations. Computer simulations and in vitro experiments showed that the new approach was robust in terms of the capture range, required significantly less iterations to converge and achieved good registration and kinematic accuracy when compared to existing techniques and to the ‘gold-standard’ Roentgen stereo analysis.

  20. Imaging, Navigation, and Robotics in Spine Surgery.

    PubMed

    Johnson, Norbert

    2016-04-01

    Spinal technology involves imaging, navigation, and robotics-collectively known as "image-guided therapy." Imaging coupled with navigation enhances visualization of irregular anatomy, enabling less invasive procedures. With robotics surgeons can perform quicker and safer hand movements with increased accuracy. In the 1890s, X-rays were invented by Roentgen. The first piece of X-ray equipment, the Cryptoscope, would take an image for 15 minutes, with the surgeon placing his hand in front of the beam to guide calibration; radiation exposure for both surgeon and patient was extreme. In the 1950s, fluoroscopy (C-arm) was invented. In the 1970s, computer-assisted tomography (CAT), known as CAT scan, became available; magnetic resonance imaging had its beginnings in the 1980s, and in 1985, the first robotic surgery was performed to obtain a neurosurgical biopsy specimen. The concept of navigation was introduced in the 1990s, and today's niche products for navigation came onto the market in the 2000s. PMID:27015071

  1. Digital Subtraction Arteriography: Now And The Future

    NASA Astrophysics Data System (ADS)

    Crummy, Andrew B.

    1982-12-01

    Roentgen discovered x-rays in late 1895 and published his first paper on the subject December 28, 1895. Almost immediately it was recognized that blood and surrounding tissues provided similar x-ray attenuation and that studies of the cardiovascular system would require the use of some intravascular contrast medium. The first arteriogram was reported in January, 1896, by Haschek and Lindenthal who injected the arteries of a cadaver forearm with a medium that was largely calcium carbonate. It was not until 1927 that Moniz of Portugal reported the first successful arteriograms in patients. He studied the intracranial vasculature with iodinated contrast material which was injected by means of a needle placed in a surgically exposed carotid artery. In 1929, Dos Santos and his colleagues performed aortography with the contrast agent injected into the aorta by way of a translumbar approach. The same group also used one of the earliest pressure injections to ensure rapid delivery of the contrast material. These workers were using iodine as the atom which was incorporated into the contrast medium. Iodine has good biological compatibility and shows an abrupt increase in its x-ray attenuation coefficient at 33 kiloelectron volts and in the energy range commonly used in diagnostic x-ray images it is more efficient in producing x-ray shadows than lead. Iodine remains the contrast atom of choice.

  2. The calibration and testing of the eROSITA X-ray mirror assemblies

    NASA Astrophysics Data System (ADS)

    Burwitz, Vadim; Predehl, Peter; Friedrich, Peter; Bräuninger, Heinrich; Eder, Josef; Pfeffermann, Elmar; Burkert, Wolfgang; Dennerl, Konrad; Hartner, Gisela; Menz, Benedikt; Fürmetz, Maria; Valsecchi, Giuseppe; Marioni, Fabio; Grisoni, Gabriele

    2014-07-01

    In 2016 the X-ray Survey Telescope eROSITA, designed and built at MPE, will be launched on the Russian Spektr- Roentgen-Gamma Mission. A compact bundle of 7 co-aligned mirror modules with a focal length of 1600 mm and 54 nested mirror shells each form the X-ray telescope. The sensitivity of the telescope in terms of effective area, field-ofview (61'), and angular resolution (~16" HEW on-axis) will yield a high grasp of about 1000 cm2 deg2 around 1 keV with an average angular resolution of ~26" HEW over the field-of-view (30" including optical and spacecraft error contributions). All flight mirror modules including a flight spare have been completed and passed their acceptance tests in December 2013. The mirror modules now have all been mated with their corresponding X-ray baffles to form mirror assemblies and the passed rigorous environmental vibration and thermal cycling tests. Here we report on the results of these measurements and on the calibration measurements planned for the completed flight mirror assemblies.

  3. Auroral X-ray Emission at Jupiter

    NASA Astrophysics Data System (ADS)

    Jager, N. O.; Cravens, T. E.; Schultz, D. R.; Stancil, P. C.; Kharchenko, V.; Dalgarno, A.

    2008-12-01

    Auroral emissions from Jupiter have been observed across the electromagnetic spectrum including ultraviolet and X-ray emissions. X-ray emissions with a total power of about 1GW were observed by the Einstein Observatory, the Roentgen satellite (ROSAT), Chandra X-ray Observatory (CXO), and XMM-Newton. Previous studies (Cravens et al. 1995, Kharchenko et al. 1998, 2006, and Liu and Schultz 1999) have shown that precipitating energetic sulfur and oxygen ions can produce the observed X-rays. Sulfur and oxygen ions in the outer magnetosphere are presumably accelerated by field-aligned potentials before they precipitate into the atmosphere (Cravens et al. 2003). Collisions with atmospheric neutrals remove most of the incident ions' orbital electrons and subsequent charge transfer collisions produce X-rays. This study theoretically models the ion precipitation using cross sections for these charge exchange processes and an empirical stopping power. X-ray luminosities are determined for several monoenergetic beams. Our model also shows the altitude dependence of the X-ray photons produced and accounts for the change in observed X-ray power due to opacity effects.

  4. Quantitative X-Ray Imaging of Intraplaque Hemorrhage in Aortas of ApoE-/-/LDL-/- Double Knockout Mice

    SciTech Connect

    Langheinrich,A.; Michniewicz, A.; Sedding, D.; Lai, B.; Jorgensen, S.; Bohle, R.; Ritman, E.

    2007-01-01

    Objectives: To determine if hemorrhage into an arterial wall can be detected in CT images by virtue of the iron content. Materials and Methods: Aortas from male apoE-/-/LDL-/- mice (n = 31) were infused in situ with contrast agent, for micro-CT scanning and histology. Roentgen-opacities within the aortic walls were identified by histology and micro-x-ray fluorescence to be iron or calcium. Dual-energy scanning was performed at 2 energy levels using synchrotron-based micro-CT [(2 {mu}m)3 voxels, 16 and 20 keV] and 64-slice CT (0.4 x 0.4 x 0.6 mm voxels, 80 and 120 kVp). Results: Opacities were identified as hemorrhage-related clusters of multiple punctate deposits, containing both Fe (0.48 x 10-12 g/voxel) and Ca (3.18 x 10-2 g/voxel), or as isolated confluent accumulations of exclusively calcium. Subtraction of the dual-energy CT scans discriminated iron from calcium deposits. Conclusion: Detection and quantification of iron deposits in hemorrhaged atherosclerotic lesions is feasible by dual-energy CT imaging.

  5. Computer assisted versus conventional cemented total knee prostheses alignment accuracy and micromotion of the tibial component

    PubMed Central

    van Strien, Thisbe; van der Linden-van der Zwaag, Enrike; Kaptein, Bart; van Erkel, Arjan; Valstar, Edward

    2008-01-01

    We evaluated the influence of CT-free or CT-based computer assisted orthopaedic surgery (CAOS) on the alignment of total knee prostheses (TK) and micromotion of tibial components. This randomised study compared 19 CT-free, 17 CT-based CAOS TK, and a matched control group of 21 conventionally placed TK. Using Roentgen stereophotogrammetric analysis (RSA) the migration was measured. The alignment and component positions were measured on radiographs. No significant difference in leg and tibial component alignment was present between the three groups. A significant difference was found for micromotion in subsidence, with the conventional group having a mean of 0.16 mm, compared to the CT-free group at 0.01 mm and the CT-based group at −0.05 mm. No clinical significant difference in alignment was found between CAOS and conventionally operated TK. More subsidence of the tibial component was seen in the conventional group compared to both CAOS groups at two year follow-up. PMID:18758777

  6. The carbon-based structures synthesized through nuclear reactions in helium at 1.1 kbar pressure under irradiation with braking γ-rays of 10 MeV threshold energy

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wisniewski, R.; Wilczynska-Kitowska, T.

    2015-01-01

    A helium high-pressure chamber (HeHPC), made from beryllium bronze, filled with gaseous helium at an initial pressure of about 1.1 kbar was irradiated by braking γ-rays of 10 MeV threshold energy during 1.0×105 \\text{s} at an electron beam current 22\\text-24 μ \\text{A} . Before opening of the chamber, the residual pressure inside was equal to 430 bar. Synthesized foils of black colour and other multiple objects were found inside the HeHPC at the inner surfaces of the reaction chamber made of high-purity copper, at the entrance window for γ-rays of beryllium bronze, and at the copper collector of nuclear and chemical reaction products. The element analysis using scanning electron microscopy (SEM) and microprobe roentgen analysis (MPRA) allowed us to establish that the foils were predominantly made of carbon and smaller quantities of other elements from carbon to iron. The developed approach agrees well with a series of studies carried out by the authors where dense hydrogen and deuterium gases are acted on by γ-rays in the presence or absence of metals in the reaction chamber.

  7. Clinical management of a fused upper premolar with supernumerary tooth: a case report.

    PubMed

    Cho, Kyu-Min; Jang, Ji-Hyun; Park, Sang-Hyuk

    2014-11-01

    In dentistry, the term 'fusion' is used to describe a developmental disorder of dental hard tissues. In the permanent dentition, fusion of a normal tooth and a supernumerary tooth usually involves the incisors or canines. However, a few cases of fusion involving premolars have also been reported to date. We present a rare case in which fusion of the maxillary left second premolar and a supernumerary tooth in a 13-year-old girl was diagnosed using cone beam computed tomography (CBCT, Alphard-3030, Asahi Roentgen Ind. Co., Ltd.). The tooth was bicuspidized after routine nonsurgical root canal treatment, and the separated teeth underwent appropriate restoration procedures. The second premolar and supernumerary tooth remained asymptomatic without any signs of inflammation after a follow-up period of 9 years. Identification of anatomical anomalies is important for treatment in cases involving fusion with supernumerary tooth, and therefore the microscopic examinations and CBCT are essential for the diagnosis. Fused teeth can be effectively managed by the comprehensive treatment which includes both endodontic and periodontal procedures. PMID:25383352

  8. Estimated skin exposure as an indicator for comparing radiovisiography (RVG) versus conventional Ektaspeed Plus dental radiography.

    PubMed

    Jones, G A; Schuman, N J; Woods, M A

    1998-01-01

    An Everest 3000 Radiovisiography (RVG) Video system (Trophy USA Inc., Fredericksburg, VA 22402) was compared with conventional radiography using Ektaspeed Plus film (Eastman Kodak Co., Rochester, NY 14650). Previous studies of the RVG system with a special computer controlled x-ray timer (Trophy USA, Inc.) claimed a significant reduction in radiation. Trophy has also claimed that the RVG system can provide diagnostic quality images utilizing existing conventional x-ray generators. This study used a conventional timer and generator. Since it would be logical to assume that many practitioners would use the equipment "in place" rather than invest in new, unfamiliar equipment. Estimated Skin Exposure (air) was used as the primary criteria for comparative purposes. Exposure has been defined as "a measure of radiation quantity, the capacity of ionize air. The roentgen (R), is the traditional unit of radiation exposure measured in air"; The results indicate that the RVG system when combined with a standard conventional timer actually generated greater radiation exposure than does standard, routine radiography. PMID:9643185

  9. The composition and structure of white dwarf atmospheres revealed by extreme ultraviolet spectroscopy

    NASA Technical Reports Server (NTRS)

    Barstow, Martin A.; Hubeny, Ivan; Lanz, Thierry; Holberg, Jay B.; Sion, Edward M.

    1995-01-01

    The ROentgen SATellite (ROSAT) and Extreme UltraViolet Explorer (EUVE) all-sky surveys have resulted in an important change in our understanding of the general composition of hydrogen-rich DA white dwarf atmospheres, with the photospheric opacity dominated by heavy elements rather than helium in the hottest stars (T > 40, 000 K). Most stars cooler than 40,000 K have more or less pure H atmospheres. However, one question, which has not been resolved, concerned the specific nature of the heavy elements and the role of helium in the hottest white dwarfs. One view of white dwarf evolution requires that H-rich DA stars form by gravitational settling of He from either DAO or He-rich central stars of planetary nebulae. In this case, the youngest (hottest) DA white dwarfs may still contain visible traces of He. Spectroscopic observations now available with EUVE provide a crucial test of these ideas. Analysis of data from the EUVE Guest Observer programme and EUVE public archive allows quantitative consideration of the sources of EUV opacity and places limits on the abundance of He which may be present.

  10. The Most Distant X-Ray Clusters

    NASA Technical Reports Server (NTRS)

    Dickinson, Mark

    1999-01-01

    In this program we have used ROSAT (Roentgen Satellite Mission) to observe X-ray emission around several high redshift radio galaxies in a search for extended, hot plasma which may indicate the presence of a rich galaxy cluster. When this program was begun, massive, X-ray emitting galaxy clusters were known to exist out to to z=0.8, but no more distant examples had been identified. However, we had identified several apparently rich clusters around 3CR radio galaxies at z greater than 0.8, and hoped to use ROSAT to confirm the nature of these structures as massive, virialized clusters. We have written up our results and submitted them as a paper to the Astrophysical Journal. This paper has been refereed and requires some significant revisions to accommodate the referees comments. We are in the process of doing this, adding some additional analysis as well. We will resubmit the paper early in 2000, and hopefully will meet with the referee's approval. We are including three copies of the submitted paper here, although it has not yet been accepted for publication.

  11. Microcontrolled pyro-electric instrument for measuring X-ray intensity in mammography.

    PubMed

    de Paula, M H; de Carvalho, A A; Brassalotti, A L; Alter, A J; Sakamoto, W K; Malmonge, J A; de Almeida, A

    2005-11-01

    A novel instrument for measurement of X-ray intensity from mammography consists of a sensitive pyro-electric detector, a high-sensitivity, low-noise current-to-voltage converter, a microcontroller and a digital display. The heart of this device, and what makes it unique is the pyro-electric detector, which measures radiation by converting heat from absorbed incident X-rays into an electric current. This current is then converted to a voltage and digitised. The detector consists of a ferro-electric crystal; two types were tested: lithium tantalate and lithium niobate. X-ray measurement in mammography is challenging because of its relatively low photon energy range, from 11 keV to 15 keV equivalent mean energy, corresponding to a peak tube potential from 22 to 36 kV. Consequently, energy fluence rate or intensity is low compared with that of common diagnostic X-ray. The instrument is capable of measuring intensities as low as 0.25 mW m(-2) with precision greater than 99%. Not only was the instrument capable of performing in the clinical environment, with high background electromagnetic interference and vibration, but its performance was not degraded after being subjected to 140 roentgen (3.6 x 10(-2) C kg(-2) air) as measured by piezo-electric (d33) or pyro-electric coefficients. PMID:16594302

  12. 100-DR-1 radiological surveys

    SciTech Connect

    Naiknimbalkar, N.M.

    1994-01-28

    This report summarizes and documents the results of the radiological surveys conducted over the surface of the 100-DR-1 Operable Unit, Hanford Site, Richland, Washington. In addition, this report explains the survey methodology using the Ultrasonic Ranging and Data System (USRADS). The 100-DR-1 radiological survey field task consisted of two activities: characterization of the operable unit-specific background conditions and the radiological survey of the operable unit surface area. The survey methodology was based on utilization of USRADS for automated recording of the gross gamma radiation levels at or near 6 in. and at 3 ft from the surface soil. The purpose of the survey is to identify the location of unidentified subsurface radioactive material areas and any surface contamination associated with these areas. The radiological surveys were conducted using both a digital count rate meter with a NaI detector reporting in counts per minute (CPM) and a dose rate meter reporting micro-Roentgen per hour (uR) connected to a CHEMRAD Tennessee Corp. Series 2000 USRADS. The count rate meter was set for gross counting, i.e., Window ``out``. The window setting allows detection of low, intermediate, and high energy photons. The USRADS equipment is used to record the detector readings verses the location of the readings, generate a map of the survey area, and save the data on computer storage media.

  13. Multi-scale visual words for hierarchical medical image categorisation

    NASA Astrophysics Data System (ADS)

    Markonis, Dimitrios; Seco de Herrera, Alba G.; Eggel, Ivan; Müller, Henning

    2012-02-01

    The biomedical literature published regularly has increased strongly in past years and keeping updated even in narrow domains is difficult. Images represent essential information of their articles and can help to quicker browse through large volumes of articles in connection with keyword search. Content-based image retrieval is helping the retrieval of visual content. To facilitate retrieval of visual information, image categorisation can be an important first step. To represent scientific articles visually, medical images need to be separated from general images such as flowcharts or graphs to facilitate browsing, as graphs contain little information. Medical modality classification is a second step to focus search. The techniques described in this article first classify images into broad categories. In a second step the images are further classified into the exact medical modalities. The system combines the Scale-Invariant Feature Transform (SIFT) and density-based clustering (DENCLUE). Visual words are first created globally to differentiate broad categories and then within each category a new visual vocabulary is created for modality classification. The results show the difficulties to differentiate between some modalities by visual means alone. On the other hand the improvement of the accuracy of the two-step approach shows the usefulness of the method. The system is currently being integrated into the Goldminer image search engine of the ARRS (American Roentgen Ray Society) as a web service, allowing concentrating image search onto clinically relevant images automatically.

  14. Soft proton scattering efficiency measurements on x-ray mirror shells

    NASA Astrophysics Data System (ADS)

    Diebold, Sebastian; Tenzer, Chris; Perinati, Emanuele; Santangelo, Andrea; Freyberg, Michael; Friedrich, Peter; Jochum, Josef

    2015-06-01

    In-orbit experience has shown that soft protons are funneled more efficiently through focusing Wolter-type optics of X-ray observatories than simulations predicted. These protons can degrade the performance of solid-state X-ray detectors and contribute to the instrumental background. Since laboratory measurements of the scattering process are rare, an experiment for grazing angles has been set up at the accelerator facility of the University of Tübingen. Systematic measurements at incidence angles ranging from 0.3° to 1.2° with proton energies around 250 keV, 500 keV, and 1 MeV have been carried out. Parts of spare mirror shells of the eROSITA (extended ROentgen Survey with an Imaging Telescope Array) instrument have been used as scattering targets. This publication comprises a detailed description of the setup, the calibration and normalization methods, and the scattering efficiency and energy loss results. A comparison of the results with a theoretical scattering description and with simulations is included as well.

  15. Induction of transpositions of MGE Dm412 by {gamma}-radiation in an isogenic line of Drosophila melanogaster

    SciTech Connect

    Zabanov, S.A.; Vasil`eva, L.A.; Ratner, V.A. |

    1995-06-01

    In an isogenic line of Drosophila, transpositions of mobile genetic elements (MGE) Dm412 were induced by {gamma}-radiation at doses of 300, 800, and 1300 R. The rates of induced transpositions were (for each dose, respectively) 3.9 x 10{sup {minus}3}, 1.0 x 10{sup {minus}2}, and 1.87 x 10{sup {minus}2} events per occupied site per haploid genome of the isogenic line per generation. Thus, the transposition rate increased linearly with the radiation dose. The specific rate of {gamma}-radiation-induced transpositions was (1.3 {+-} 0.6) x 10{sup {minus}5} per occupied site per haploid genome of the isogenic line per Roentgen per generation. {gamma}-Radiation-induced hot transposition sites and haplotypes, very similar to those induced by heat shock, were found. It was suggested that the mechanism of induction by {gamma}-radiation involves the heat shock system. Thus, it is more similar to the mechanism of temperature induction than to the direct mutational effect of {gamma}-radiation. Estimates of induced transposition rates per genome for each dose were calculated as 1.1, 3.0, and 5.6 events, respectively, per genome per generation. This level probably corresponds to the subthreshold level of genomes near the {open_quotes}catastrophic border of transpositional losses.{close_quotes} 21 refs., 1 fig., 4 tabs.

  16. Global Studies of Molecular Clouds in the Galaxy, The Magellanic Clouds, and M31

    NASA Technical Reports Server (NTRS)

    Thaddeus, Patrick

    1999-01-01

    Over the course of this grant we used various spacecraft surveys of the Galaxy and M31 in conjunction with our extensive CO spectral line surveys to address central problems in galactic structure and the astrophysics of molecular clouds. These problems included the nature of the molecular ring and its relation to the spiral arms and central bar, the cosmic ray distribution, the origin of the diffuse X-ray background, the distribution and properties of x-ray sources and supernova remnants, and the Galactic stellar mass distribution. For many of these problems, the nearby spiral M31 provided an important complementary perspective. Our CO surveys of GMCs (Galactic Molecular Clouds) were crucial for interpreting Galactic continuum surveys from satellites such as GRO (Gamma Ray Observatory), ROSAT (Roentgen Satellite), IRAS (Infrared Astronomy Satellite), and COBE (Cosmic Background Explorer Satellite) because they provided the missing dimension of velocity or kinematic distance. GMCs are a well-defined and widespread population of objects whose velocities we could readily measure throughout the Galaxy. Through various emission and absorption mechanisms involving their gas, dust, or associated Population I objects, GMCs modulate the galactic emission in virtually every major wavelength band. Furthermore, the visibility. of GMCs at so many wavelengths provided various methods of resolving the kinematic distance ambiguity for these objects in the inner Galaxy. Summaries of our accomplishments in each of the major wavelength bands discussed in our original proposal are given

  17. X-ray Variability in the Hot Supergiant zgr Orionis.

    PubMed

    Berghöfer, T W; Schmitt, J H

    1994-09-16

    Hot massive stars represent only a small fraction of the stellar population of the galaxy, but their enormous luminosities make them visible over large distances. Therefore, they are ideal standard candles, used to determine distances of near galaxies. Their mass loss due to supersonic winds driven by radiation pressure contributes significantly to the interstellar medium and thus to the chemical evolution of galaxies. All hot stars are soft x-ray sources; in contrast to the sun with its highly variable x-ray flux, long time scale x-ray variability is not common among hot stars. An analysis is presented here of an unusual increase in x-ray flux observed with the roentgen observatory satellite during a period of 2 days for the hot supergiant zeta Orionis, the only episode of x-ray variability that has been found in a hot star. These observations provide the most direct evidence so far for the scenario of shock-heated gas in the winds of hot stars. PMID:17770897

  18. [SURGICAL TREATMENT OF POSTOPERATIVE STRICTURE OF ANAL CHANNELL].

    PubMed

    Shevchuk, I M; Sadoviy, I Ya; Novytskiy, O V

    2015-09-01

    The results of treatment of 50 patients, suffering postoperative stricture of anal channell (SACH), who were treated in Proctology Department of Ivano-Frankivskiy Rural Clinical Hospital in 2006-2014 yrs, were analyzed. After conduction of hemorrhoidectomy in accordance to Milligan-Morgan method for chronic hemorrhoids grades III-IV a SACH have occurred in 46 (92%) patients, excision of a chronic anal fissura was performed in 3 (6%) and excision of perianal pointed condylomas--in 1 patient. In 2006-2007 yrs 11 (22%) patients were operated in accordance to approaches, which were conventional at that time (comparison group). In 2008 - 2014 yrs 39 (78%) patients were admitted to hospital (main group), in whom new approaches for diagnosis, conservative and surgical treatment were applied, 30 (76.9%) of them were operated. The proposed method on isolated roentgen contrast investigation of anal channell have permitted to determine objectively a form, diameter and grade of the anal channel stricture, and it may be applied as a screening procedure, as additional objective criterion while choosing a surgical tactic. Application of the improved operative technique for SACH have permitted to lower its occurrence rate from 45.4 to 6.7%. PMID:26817078

  19. Status of ART-XC/SRG instrument

    NASA Astrophysics Data System (ADS)

    Pavlinsky, M.; Akimov, V.; Levin, V.; Lapshov, I.; Tkachenko, A.; Semena, N.; Buntov, M.; Glushenko, A.; Arefiev, V.; Yaskovich, A.; Sunyaev, R.; Churazov, E.; Gilfanov, M.; Grebenev, S.; Sazonov, S.; Revnivtsev, M.; Lutovinov, A.; Molkov, S.; Kudelin, M.; Drozdova, T.; Garanin, S.; Grigorovich, S.; Litvin, D.; Lazarchuk, V.; Roiz, I.; Garin, M.; Babyshkin, V.; Lomakin, I.; Menderov, A.; Moskvinov, D.; Gubarev, M.; Ramsey, B.; Kilaru, K.; O'Dell, S. L.; Kolodziejczak, J.; Elsner, R.

    2014-07-01

    Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in March 2016 from Baikonur, by a Zenit rocket with a Fregat booster and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopes - a softx- ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules. The NASA Marshall Space Flight Center (MSFC) is fabricating the flight mirror modules for the ART-XC/SRG. Each mirror module will be aligned with a focal plane CdTe double-sided strip detector which will operate over the energy range of 6-30 keV, with an angular resolution of <1', a field of view of ~34' and an expected energy resolution of about 10% at 14 keV.

  20. Status of ART-XC / SRG instrument

    NASA Astrophysics Data System (ADS)

    Pavlinsky, M.; Akimov, V.; Levin, V.; Krivchenko, A.; Rotin, A.; Kuznetsova, M.; Lapshov, I.; Tkachenko, A.; Semena, N.; Buntov, M.; Glushenko, A.; Arefiev, V.; Yaskovich, A.; Grebenev, S.; Sazonov, S.; Revnivtsev, M.; Lutovinov, A.; Molkov, S.; Krivonos, R.; Serbinov, D.; Kudelin, M.; Drozdova, T.; Voronkov, S.; Sunyaev, R.; Churazov, E.; Gilfanov, M.; Babyshkin, V.; Lomakin, I.; Menderov, A.; Gubarev, M.; Ramsey, B.; Kilaru, K.; O'Dell, S. L.; Kolodziejczak, J.; Elsner, R.; Zavlin, V.; Swartz, D.

    2015-09-01

    Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in beginning 2017 from Baikonur and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopes - a soft-x-ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules. The ART-XC flight mirror modules has been developed and fabricated at the NASA Marshall Space Flight Center (MSFC). Each mirror module will be aligned with a focal plane CdTe double-sided strip detector which will operate over the energy range of 6-30 keV, with an angular resolution of <1', a field of view of ~34' and an expected energy resolution of about 12% at 14 keV. The current status of the ART-XC/SRG instrument will be present.

  1. Virtual modeling of robot-assisted manipulations in abdominal surgery

    PubMed Central

    Berelavichus, Stanislav V; Karmazanovsky, Grigory G; Shirokov, Vadim S; Kubyshkin, Valeriy A; Kriger, Andrey G; Kondratyev, Evgeny V; Zakharova, Olga P

    2012-01-01

    AIM: To determine the effectiveness of using multidetector computed tomography (MDCT) data in preoperative planning of robot-assisted surgery. METHODS: Fourteen patients indicated for surgery underwent MDCT using 64 and 256-slice MDCT. Before the examination, a specially constructed navigation net was placed on the patient’s anterior abdominal wall. Processing of MDCT data was performed on a Brilliance Workspace 4 (Philips). Virtual vectors that imitate robotic and assistant ports were placed on the anterior abdominal wall of the 3D model of the patient, considering the individual anatomy of the patient and the technical capabilities of robotic arms. Sites for location of the ports were directed by projection on the roentgen-positive tags of the navigation net. RESULTS: There were no complications observed during surgery or in the post-operative period. We were able to reduce robotic arm interference during surgery. The surgical area was optimal for robotic and assistant manipulators without any need for reinstallation of the trocars. CONCLUSION: This method allows modeling of the main steps in robot-assisted intervention, optimizing operation of the manipulator and lowering the risk of injuries to internal organs. PMID:22816028

  2. BeppoSAX Observations of MKN 110

    NASA Technical Reports Server (NTRS)

    Nicastro, Fabrizio; Oliversen, Ronald J. (Technical Monitor)

    2002-01-01

    Mkn 110 is a bright, nearby Seyfert 1 galaxy, which underwent a long optical monitoring campaign, during the past 12 years. Optical observations show that Mkn 110 vary, both in flux and spectral shape. The intensity and width of its Broad Emission Lines (BELs) also vary, from typical Seyfert 1, to typical Narrow Line Seyfert 1 (NLSyl) values, so suggesting that this could be the first supermassive black holes where accretion state related transitions, as frequently observed in stellar-size black holes, have finally been observed. To verify these suggestions we asked to monitor Mkn 110 with BeppoSAX with three 50 ksec observations six months apart. The goal of the proposal was to observe spectral variations in X-ray, already suggested by previous, existing ROSAT (Roentgen Satellite) and ASCA (Advanced Satellite for Cosmology and Astrophysics) observations of the same source. The first of these three SAX (Satellite per Astronomia X) observations was taken on May 2000, and lacks the Low-Energy instrument (0.1-2 keV is the band in which NLSy1 and Sy1 X-ray spectra differ most).

  3. The eROSITA/SRG All-Sky Survey: A new era of large-scale structure studies with AGN

    NASA Astrophysics Data System (ADS)

    Kolodzig, A.; Gilfanov, M.; H"utsi, G.; Sunyaev, R.

    2014-07-01

    The four-year X-ray all-sky survey (eRASS) of the eROSITA telescope aboard the Spektrum-Roentgen-Gamma (SRG) satellite will detect ˜3 million active galactic nuclei (AGN) with a median redshift of z≈1 and typical luminosity of L_{0.5-2.0keV}˜10^{44} erg s^{-1}. We show that this unprecedented AGN sample, complemented with redshift information, will supply us with outstanding opportunities for large-scale structure research. For the first time with a sample of X-ray selected AGN, it will become possible to perform detailed redshift- and luminosity-resolved studies of the linear bias factor. These studies will dramatically improve our understanding of AGN environment, triggering mechanisms, growth of super-massive black holes and their co-evolution with dark matter halos. The eROSITA AGN sample will become a powerful cosmological probe. It will become possible to convincingly detect baryonic acoustic oscillations (BAOs) with ˜8σ confidence in the 0.8

  4. Evolution of urological imaging.

    PubMed

    Bueschen, Anton J; Lockhart, Mark E

    2011-02-01

    The evolution of urological imaging has had a major impact on the diagnosis and treatment of urological diseases since the discovery of the X-ray by Roentgen in 1895. Early developments included plain films of the abdomen, retrograde urographic techniques, development of contrast media, excretory urography, renal mass puncture, renal angiography, cystography and nuclear medicine procedures. These procedures led to the maturation of the specialties of diagnostic radiology and urology, and the development of the subspecialties of pediatric urology and urological radiology during the first seven decades of the 20th century. Subsequently, many imaging advances have occurred leading to changes in diagnosis and management of urological patients. Ultrasound and cross-sectional imaging technologies (computed tomography and magnetic resonance imaging) are increasingly applied in urological evaluation, treatment and surveillance. Current developments include dual energy computed tomography, positron emission tomography computed tomography, renal donor and renal transplant imaging, prostate magnetic resonance imaging, and microbubble contrast enhanced ultrasound. Imaging advances will continue. It is the responsibility of all physicians to assess the advantages of new developments while weighing those advantages against the additional radiation exposure and the costs associated with new procedures. PMID:21114686

  5. [The role of neurovisualization methods in diagnosis and verification of vertigo etiology].

    PubMed

    Alekseeva, N S; Krotenkova, M V; Konovalov, R N; Kirichenko, I M; Baev, A A; Petrova, E I

    2006-01-01

    Roentgen computed tomography (RCT) and MR-imaging (MRI) were used in investigation of vertigo etiology and affection of the cochleovestibular analyzer in 130 patients aged 28 to 74 years with recurrent systemic rotatory vertigo or its other symptoms. All the patients have undergone comprehensive otoneurological examination, RCT and MRI which showed that peripheral cochleovestibular syndromes (PCVS) caused by arterial hypertension (AH), atherosclerosis (AS), vascular dystonia (VD) are rarely characterized by focal alterations in the brain. PCVS comparison with blood flow in the vertebral arteries (VA) detected most frequently anomalies and asymmetries of the diameters. MR-angiography plays an important role in verification of pathology of intracranial VA. In central cochleovestibular syndrome (CCVS) with AH, AS, VD, principal pathological changes were registered in the brain trunk and cerebellum by MRI. Vestibulometry and otoneurological method detect not only vascular cochleovestibular peripheral and central syndromes but also to make differential diagnosis. RCT and MRI verify cochleovestibular syndromes in patients with multiple encephalomyelitis, VIII nerve neurinoma and tumors of the posterior cranial fossa. PMID:16482004

  6. X-ray-induced changes in growth of Mozambique tilapia

    SciTech Connect

    Jana, B.B.; Basu, M.

    1995-01-01

    Early fry (30 d postfertilization) and 7-8-week-old Mozambique tilapias (Tilapia mossambica) were exposed to X rays in dosages of 50, 100, 200, 300, 400 or 500 roentgens and reared in outdoor culture tanks between May 1981 and October 1988. Fish of either sex that were irradiated as fry grew faster than controls at all test X-ray doses. Among fish irradiated at 7-8 weeks, males grew significantly faster, but females grew significantly slower, than controls at all test doses. X-ray-induced changes in growth were dose-dependent: growth rates of fry (both sexes) and of juvenile males rose relative to those of controls with increased radiation dose. The growth increase per unit of radiation dose was higher for fry than for older juveniles. The length-weight regression was steeper for irradiated males than for controls. The average weights of F{sub 1} offspring of irradiated fish were greatly reduced as compared with controls, which suggests the transfer of the detrimental effects of X rays from irradiated parents to their offspring. 39 refs., 3 figs., 3 tabs.

  7. Repeat validation of a method to measure in vivo three dimensional hip kinematics using computed tomography and fluoroscopy.

    PubMed

    Hossain, Md Mowrin; Alam, Md Jahangir; Pickering, Mark R; Ward, Thomas; Perriman, Diana; Scarvell, Jennie M; Smith, Paul N

    2014-01-01

    Total hip arthroplasty or THA is a surgical procedure for the relief of significant disabling pain caused by osteoarthritis or hip fracture. Knowledge of the 3D kinematics of the hip during specific functional activities is important for THA component design. In this paper we compare kinematic measurements obtained by a new 2D-3D registration algorithm with measurements provided by the gold standard roentgen stereo analysis (RSA). The study validates a promising method for investigating the kinematics of some pathologies, which involves fitting three dimensional patient specific 3D CT scans to dynamic fluoroscopic images of the hip during functional activities. This is the first study in which single plane fluoroscopy has been used for kinematic measurements of natural hip bones. The main focus of the study is on the out-of-plane translation and rotation movements which are difficult to measure precisely using a single plane approach. From our experimental results we found that the precision of our proposed approach compares favourably with that of the most recent dual plane fluoroscopy approach. PMID:25571375

  8. Absorbed dose to water: Standards and traceability for radiation oncology

    SciTech Connect

    Almond, P.R.

    1995-12-31

    Although the need for appropriate quantities and units for ionizing radiation has existed since shortly after discovery of X-rays, the quantities and units in general use today were not completely formalized until about 15 years ago. The development of appropriate national and international standards have also been ongoing. For many years the quantity, exposure, measured in units of roentgen was the national standard and they were also the quantity and units in which radiotherapy was described. With the introduction of megavoltage X-ray and electron-beam equipment and the adoption of the quantity {open_quotes}absorbed-dose{close_quotes} measured in units of rad (or gray) different approaches to calibrating these beams were needed. This was especially the case since the national standard in terms of exposure at a maximum photon energy for {sup 60}Co gamma rays was only available. Since the late 1960s various machine calibration protocols have been published. These protocols have to accommodate changes in modality, energy, quantities and units between the national standard and the user. Because of this, a new definition of traceability is proposed to accommodate the present system. By recording all intercomparisons and parameters used, an auditable calibration chain can be maintained. Even with the introduction of calibration protocols based upon national absorbed dose standards, the proposed traceability definition will still be needed.

  9. The particle background of the Rosat PSPC. [Position Sensitive Proportional Counter

    NASA Technical Reports Server (NTRS)

    Snowden, S. L.; Plucinsky, P. P.; Briel, U.; Hasinger, G.; Pfeffermann, E.

    1992-01-01

    In order to permit quantitative studies of the diffuse cosmic X-ray background and of extended X-ray sources, the particle induced background of the Roentgen Satellite, Rosat, Position Sensitive Proportional Counter (PSPC) is parameterized. Data collected during 210,000 s of PSPC operation have been analyzed and the temporal, spectral, and spatial distributions investigated. About 77 percent of the residual events originate within the detector while the remainder enter through the counter window. During typical conditions, the count rate of the residual events is well correlated with the Master Veto (MV) count rate. The spectrum of these events is well described by a flat component plus a soft power law and an Al K-alpha line at 1.5 keV. Also during typical conditions, the ratio between the power law and flat components remains constant to +/- 4 while the relative Al K-alpha contribution increases with increasing MV count rate. The distribution of the counts over the field of view is uniform except for a slight radial dependence and shadowing caused by blockage of the externally produced component by the window support structure.

  10. Entire litters developed from transferred eggs in whole body x-irradiated female mice

    SciTech Connect

    Lin, T.P.

    1980-07-01

    The sensitivity of mouse eggs to sublethal x-irradiation was determined in vitro and in vivo with regard to the development of donor litters in foster mothers. One thousand seven hundred fifty-eight unfertilized eggs of agouti dark-eyed donor mice were transferred into 293 unirradiated or x-irradiated, mated female pink-eyed mice. Two hundred thirty-nine recipients became pregnant; of these 35 produced litters containing solely dark-eyed fetuses. Sublethal doses of x-radiation administered to donor eggs in vitro before transferring into unirradiated recipients did not influence significantly the number of litters of exclusively dark-eyed fetuses produced. However, recipients irradiated by 250 roentgens (r) produced more solely dark-eyed litters than did those irradiated with 100 r. In 21 pregnant females irradiated by 100 r, only 3 (14%) developed solely dark-eyed fetuses as compared to 22 pregnant females irradiated by 250 r, of which 13 (59%) developed solely dark-eyed fetuses, all from unirradiated, transferred eggs. Of another group of 22 pregnant females which received 250 r body irradiation and subsequently received eggs also irradiated by 250 r, only 7 (32%) produced litters of dark-eyed fetuses. No one female of these three groups carried native fetuses. Such radiation-induced infertility resulting from damage of native eggs rather than loss of mother's ability to carry a pregnancy, is frequently remedied by egg transfer.

  11. The ART-XC Instrument on Board the SRG Mission

    NASA Technical Reports Server (NTRS)

    Pavlinksy, M.; Akimov, V.; Levin, V.; Lapshov, I.; Tkachenko, A.; Semena, N.; Buntov, M.; Glushenko, A.; Arefiev, V.; Yaskovish, A.; Sunyaeve, R.; Churazov, E.; Sazonov, S.; Revnivtsev, M.; Lutovinov, A.; Molkov, S.; Kudelin, M.; Garanin, S.; Grigorovich, S.; Litvin, D.; Gubarev, M.; Ramsey, B.; Kilaru, K.; ODell, S. L.; Elsner, R.

    2012-01-01

    Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in 2014 from Baikonur, by a Zenit rocket with a Fregat booster and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopes . a soft-x-ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules with seven corresponding cadmium-telluride focal plane detectors. Each will operate over the approximate energy range of 6- 30 keV, with an angular resolution of <1 ', a field of view of 30 ' and an energy resolution about 10% at 14 keV. The NASA Marshall Space Flight Center (MSFC) will fabricate some of the mirror modules, to complement others fabricated by VNIIEF in Russia.

  12. Status of ART-XC/SRG Instrument

    NASA Technical Reports Server (NTRS)

    Pavlinsky, M.; Akimov, V.; Levin, V.; Lapshov, I.; Tkachenko, A.; Semena, N.; Buntov, M.; Glushenko, A.; Arefiev, V.; Yaskovich, A.; Sunyaev, R.; Churazov, E.; Gilfanov, M.; Grebenev, S.; Sazonov, S.; Revnivtsev, M.; Lutovinov, A.; Molkov, S.; Kudelin, M.; Drozdova, T.; Garanin, S.; Grigorovich, S.; Litvin, D.; Lazarchuk, V.; Roiz, I.; Garin, M.; Babyshkin, V.; Lomakin, I.; Menderov, A.; Moskvinov, D.; Gubarev, M.; Ramsey, B.; Kilaru, K.; ODell, S. L.; Kolodziejczak, J.; Elsner, R.

    2014-01-01

    Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in March 2016 from Baikonur, by a Zenit rocket with a Fregat booster and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopes - a soft-x-ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules. The NASA Marshall Space Flight Center (MSFC) is fabricating the flight mirror modules for the ART-XC/SRG. Each mirror module will be aligned with a focal plane CdTe double-sided strip detectors which will operate over the energy range of 6-30 keV, with an angular resolution of less than 1', a field of view of approximately 34' and an expected energy resolution of about 10 percent at 14 keV.

  13. Scintillation Counters

    NASA Astrophysics Data System (ADS)

    Bell, Zane W.

    Scintillators find wide use in radiation detection as the detecting medium for gamma/X-rays, and charged and neutral particles. Since the first notice in 1895 by Roentgen of the production of light by X-rays on a barium platinocyanide screen, and Thomas Edison's work over the following 2 years resulting in the discovery of calcium tungstate as a superior fluoroscopy screen, much research and experimentation have been undertaken to discover and elucidate the properties of new scintillators. Scintillators with high density and high atomic number are prized for the detection of gamma rays above 1 MeV; lower atomic number, lower-density materials find use for detecting beta particles and heavy charged particles; hydrogenous scintillators find use in fast-neutron detection; and boron-, lithium-, and gadolinium-containing scintillators are used for slow-neutron detection. This chapter provides the practitioner with an overview of the general characteristics of scintillators, including the variation of probability of interaction with density and atomic number, the characteristics of the light pulse, a list and characteristics of commonly available scintillators and their approximate cost, and recommendations regarding the choice of material for a few specific applications. This chapter does not pretend to present an exhaustive list of scintillators and applications.

  14. Expectations and outcome of a scientifically developed hip prosthesis in 170 hips with a follow-up of 5-12 years.

    PubMed

    Van de Groes, Sebastiaan; Ypma, Jan; Spierings, Pieter; Verdonschot, Nico

    2012-10-01

    Roentgen stereophotogrammetric analysis (RSA) is commonly used to assess prosthetic stability as a predictor of the long-term clinical outcome of new total hip systems. Although the RSA technique is very accurate, it may not be trivial to interpret migration rates into clinical outcome, as critical migration rates depend heavily on the design of the prosthesis. In the present study we describe the clinical results of the Scientific Hip Prosthesis (SHP), which had unexpectedly high migration values in a clinical RSA study. We evaluated the clinical results of a single surgeon study consisting of 170 hips with a follow-up of 5-12 years (mean: 83 years). The survival rate was 98.8% at ten years for aseptic loosening of the stem. This study therefore indicates that a prosthetic design may function clinically rather well although relatively high migration rates have been reported. The prediction of clinical survival of new prosthetic components remains a challenging task and the interpretation of migration rates with new designs should be considered with much caution. PMID:23162959

  15. Early E-modulus of healing Achilles tendons correlates with late function: similar results with or without surgery.

    PubMed

    Schepull, T; Kvist, J; Aspenberg, P

    2012-02-01

    Non-operative treatment of Achilles tendon ruptures is associated with an increased risk of rerupture. We hypothesized that this is due to inferior mechanical properties during an early phase of healing, and performed a randomized trial, using a new method to measure the mechanical properties. Tantalum markers were inserted in the tendon stumps, and tendon strain at different loadings was measured by stereo-radiography (Roentgen stereophotogrammetric analysis) at 3, 7 and 19 weeks and 18 months after injury. Thirty patients were randomized to operative or non-operative treatment. The primary out-come variable was an estimate for the modulus of elasticity at 7 weeks. Strain per force, cross-sectional area and tendon elongation were also measured. The functional outcome variable was the heel-raise index after 18 months. There was no difference in the mean modulus of elasticity or other mechanical or functional variables between operative and non-operative treatments at any time-point, but strain per force at 7 and 19 weeks had a significantly larger variation in the non-operative group. This group, therefore, might contain more outliers with poor healing. The modulus of elasticity at 7 weeks correlated with the heel-raise index after 18 months in both treatment groups (r(2) =0.75; P=0.0001). This correlation is an intriguing finding. PMID:20673250

  16. Initial stability of tibial components in primary knee arthroplasty. A cadaver study comparing cemented and cementless fixation techniques.

    PubMed

    Efe, Turgay; Figiel, Jens; Danek, Susanna; Tibesku, Carsten O; Paletta, Jürgen R J; Skwara, Adrian

    2011-06-01

    The purpose of this roentgen stereophotogrammetric analysis (RSA) study was to evaluate the initial stability of cemented and cementless tibial components in vitro. Twenty tibia specimens were matched into two groups. In the first group, the tibial trays were cemented superficially and in the second group cementless fixation with stem and screws was performed. An axial load of 2000 N for 1000 and 10,000 cycles was applied onto the specimens and RSA was performed. The experimental results after 1000 cycles showed a higher migration with significant differences for the parameters maximum lift off (p = 0.011) and maximum total point motion (p = 0.002) in the cementless group. After 10,000 cycles, the migration in the cementless group increased significantly for maximum lift off (p = 0.043), maximum subsidence (p = 0.045) and maximum total point motion (p = 0.013). The higher migration rates in the cementless group demonstrate a lower initial mechanical stability of cementless tibial components which can cause an early component loosening. PMID:21845999

  17. Computer assisted versus conventional cemented total knee prostheses alignment accuracy and micromotion of the tibial component.

    PubMed

    van Strien, Thisbe; van der Linden-van der Zwaag, Enrike; Kaptein, Bart; van Erkel, Arjan; Valstar, Edward; Nelissen, Rob

    2009-10-01

    We evaluated the influence of CT-free or CT-based computer assisted orthopaedic surgery (CAOS) on the alignment of total knee prostheses (TK) and micromotion of tibial components. This randomised study compared 19 CT-free, 17 CT-based CAOS TK, and a matched control group of 21 conventionally placed TK. Using Roentgen stereophotogrammetric analysis (RSA) the migration was measured. The alignment and component positions were measured on radiographs. No significant difference in leg and tibial component alignment was present between the three groups. A significant difference was found for micromotion in subsidence, with the conventional group having a mean of 0.16 mm, compared to the CT-free group at 0.01 mm and the CT-based group at -0.05 mm. No clinical significant difference in alignment was found between CAOS and conventionally operated TK. More subsidence of the tibial component was seen in the conventional group compared to both CAOS groups at two year follow-up. PMID:18758777

  18. Fixation of total knee arthroplasty improved by mobile-bearing design.

    PubMed

    Russo, Alessandro; Montagna, Luisa; Bragonzoni, Laura; Zampagni, Maria Luisa; Marcacci, Maurilio

    2005-08-01

    We examined the in vivo displacement of mobile-bearing polyethylene and its effect on prosthesis-bone fixation. Thirty-five patients with the Interax ISA mobile platform total knee arthroplasties were examined by roentgen stereophotogrammetric analysis. Our protocol included weightbearing to measure the range of motion of the mobile platform in relation to the tibial component. We also studied the micromotions of the tibial component in relation to the tibia during a 2-year followup. The analysis of micromotion (maximum total motion mean, 0.5 mm; subsidence mean, 0.15 mm) showed this mobile platform design is stable and improves fixation at the prosthesis-bone interface. Longitudinal rotations of the mobile platform occurred in all patients and followed a homogeneous pattern of motion, depending on the examination. However, anteroposterior translations did not show any patterns with specific examination. This suggests the meniscal movement adapts itself to different weightbearing conditions. We measured the in vivo mobile-bearing displacement under static loading conditions. We also observed improved fixation at the bone-prosthesis interface. PMID:16056048

  19. Long-term implant-bone fixation of the femoral component in total knee replacement.

    PubMed

    Cristofolini, L; Affatato, S; Erani, P; Leardini, W; Tigani, D; Viceconti, M

    2008-04-01

    Success of total knee replacement (TKR) depends on the prosthetic design. Aseptic loosening of the femoral component is a significant failure mode that has received little attention. Despite the clinical relevance of failures, no protocol is available to test long-term implant-bone fixation of TKR in vitro. The scope of this work was to develop and validate a protocol to assess pre-clinically the fixation of TKR femoral components. An in vitro protocol was designed to apply a simplified but relevant loading profile using a 6-degrees-of-freedom knee simulator for 1,000000 cycles. Implant-bone inducible micromotions and permanent migrations were measured at three locations throughout the test. After test completion, fatigue damage in the cement was quantified. The developed protocol was successfully applied to a commercial TKR. Additional tests were performed to exclude artefacts due to swelling or creep of the composite femur models. The components migrated distally; they tilted towards valgus in the frontal plane and in extension in the sagittal plane. The migration patterns were consistent with clinical roentgen-stereophotogrammetric recordings with TKR. Additional indicators were proposed that could quantify the tendency to loosen/stabilize. The type and amount of damage found in the cement, as well as the migration patterns, were consistent with clinical experience with the specific TKR investigated. The proposed pre-clinical test yielded repeatable results, which were consistent with the clinical literature. Therefore, its relevance and reliability was proved. PMID:18491701

  20. Primary stability of tibial components in TKA: in vitro comparison of two cementing techniques.

    PubMed

    Skwara, Adrian; Figiel, J; Knott, T; Paletta, J R J; Fuchs-Winkelmann, S; Tibesku, C O

    2009-10-01

    In spite of improvements in cementing technique, migration of tibial component remains a problem in total knee arthroplasty. This study compares the primary stability of tibial components using two different cementing techniques with roentgen stereophotogrammetric analysis (RSA) in vitro. A total of 20 tibia specimens were matched into two groups, 10 specimens per group. Cementing technique was randomized to each group. In the first group only the base and in the second group the base and stem were cemented. The implants and the tibial metaphysis were marked with markers for the RSA analysis. All specimens were tested with an axial load of 2,000 N for 1,000 and 10,000 cycles and RSA analysis was performed. Endpoints for radiosterometric analysis were maximum total point motion, maximum subsidence, lift off, rotation and translation along the x-, y-, and z-axes. After 1,000 and 10,000 cycles, no significant differences could be found, but two tibial components of the surface cementing group showed a migration of more than 2 mm defined as failure compared to six failed tibial components in the full cementing group (P = 0.068). This higher number of failed arthroplasties in the fully cemented prosthesis group demonstrates a disadvantageous load distribution in the tibia apophysis which can cause an early component loosening. PMID:19572121

  1. The stability of the cemented tibial component of total knee arthroplasty: posterior cruciate-retaining versus posterior-stabilized design.

    PubMed

    Catani, Fabio; Leardini, Alberto; Ensini, Andrea; Cucca, Giuseppe; Bragonzoni, Laura; Toksvig-Larsen, Soren; Giannini, Sandro

    2004-09-01

    Micromotion of the tibial component in 40 knee arthroplasties for gonarthrosis was studied using Roentgen stereophotogrammetric analysis. The stability of this component was assessed for 2 years' postoperatively. In all arthroplasties, an attempt was made to reconstruct the preoperative posterior slope. Posterior cruciate-retaining (CR) and posterior-stabilized (PS) components showed at 2 years a maximum total point motion of 0.6 +/- 0.4 mm and 0.7 +/- 0.5 mm, respectively. Whereas 92.5% of the implants were determined to be stable, 1 of the CR group and 2 of the PS group displayed migration between the first and the second year of at least 0.2 mm. A negative correlation between subsidence of the tibial component at 2 years of follow-up and the difference between preoperative and postoperative tibial slope was found. Consequently, we suggest that restoring the original posterior slope of the tibial plateau must be a goal of tibial component implantation. PMID:15343540

  2. Accuracy and initial stability of open- and closed-wedge high tibial osteotomy: a cadaveric RSA study.

    PubMed

    Gaasbeek, Robert D A; Welsing, Roy T C; Verdonschot, Nico; Rijnberg, Willard J; van Loon, Corné J M; van Kampen, Albert

    2005-11-01

    We analyzed the difference in angle-correction accuracy and initial stability between open-wedge (OWO) and closed-wedge tibial valgus osteotomy (CWO). Five fresh-frozen pairs of human cadaver lower limbs were used; their bone mineral density (BMD) was measured with DEXA and a planned 7 degrees valgus osteotomy was performed, either with an open (right knees) or closed (left knees) technique. All knees for osteotomy were fixed with a rigid locked plate. In OWO, tricalcium phosphate (TCP) wedges were inserted. The knees were subjected to an increasing cyclic axial load until failure, while measuring the relative displacement of the bony segments with roentgen stereophotogrammetric analysis. The mean postoperative valgus correction angle was 9.5 degrees +/-2.8 degrees for CWO (over-correction of 2.5 degrees ) and 6.2 degrees +/-2.0 degrees for OWO (under-correction of 0.8 degrees ) (P =0.08). The data of displacement under load bearing showed no significant differences in rotations and translations in any direction. No significant correlation between BMD and the moment of failure was found (P =0.27). This study has shown that both methods gave an acceptable correction with a high variation of postoperative correction angles. There was a tendency for over-correction in the CWO group but no significant difference was found. There was no difference in initial stability between CWO and OWO with a rigid locked-plate fixation. PMID:15702355

  3. Measurement of laxity in the anterior cruciate ligament-deficient knee: a comparison of three different methods in vitro.

    PubMed

    Khan, R T; Lie, D T; Cashman, P M; Thomas, R W; Amis, A A

    2007-08-01

    The aim of this study was to compare in-vitro measurements of anteroposterior laxity in the anterior cruciate ligament (ACL)-deficient knee using three different methods: an Instron materials-testing machine, then a KT-2000 arthrometer, and finally by Roentgen stereophotogrammetric analysis (RSA). Eight ACL-deficient human cadaver knees were used. Total displacement was measured between 90 N anterior and 90 N posterior tibiofemoral drawer forces at both 20 degrees and 90 degrees knee flexion. Laxity ranged from 11.5 to 27.6 mm at 20 degrees and from 8.7 to 23.9 mm at 90degrees. A statistically significant difference was not found between the mean RSA and KT-2000 measurements. However, the mean Instron measurements of laxity were significantly (3-4 mm) higher than both RSA and KT-2000 measurements. The clinical methods of RSA and the KT-2000 measurements agreed well but appeared to underestimate tibiofemoral anteroposterior laxity compared with the materials-testing machine. These findings may be helpful in the future comparison of different studies. PMID:17937204

  4. Ten-year in vivo wear measurement of a fully congruent mobile bearing unicompartmental knee arthroplasty.

    PubMed

    Price, A J; Short, A; Kellett, C; Beard, D; Gill, H; Pandit, H; Dodd, C A F; Murray, D W

    2005-11-01

    Polyethylene particulate wear debris continues to be implicated in the aetiology of aseptic loosening following knee arthroplasty. The Oxford unicompartmental knee arthroplasty employs a spherical femoral component and a fully congruous meniscal bearing to increase contact area and theoretically reduce the potential for polyethylene wear. This study measures the in vivo ten-year linear wear of the device, using a roentgenstereophotogrammetric technique. In this in vivo study, seven medial Oxford unicompartmental prostheses, which had been implanted ten years previously were studied. Stereo pairs of radiographs were acquired for each patient and the films were analysed using a roentgen stereophotogrammetric analysis calibration and a computer-aided design model silhouette-fitting technique. Penetration of the femoral component into the original volume of the bearing was our estimate of linear wear. In addition, eight control patients were examined less than three weeks post-insertion of an Oxford prosthesis, where no wear would be expected. The control group showed no measured wear and suggested a system accuracy of 0.1 mm. At ten years, the mean linear wear rate was 0.02 mm/year. The results from this in vivo study confirm that the device has low ten-year linear wear in clinical practice. This may offer the device a survival advantage in the long term. PMID:16260665

  5. Investigation into the detection of marker movement by biplanar RSA.

    PubMed

    Montagna, Luisa; Bragonzoni, Laura; Zampagni, Maria Luisa; Russo, Alessandro; Motta, Mario; Albisinni, Ugo; Marcacci, Maurilio

    2005-10-01

    Roentgen Stereophotogrammetric Analysis (RSA) is the most accurate technique to measure micromotion between rigid bodies and it has been widely used in the orthopedic field to investigate lower limb prostheses. The aim of this paper was to investigate the factors affecting the accuracy of measurements performed on the knee joint by the biplanar RSA system. Errors were assessed by means of a test object. A particular goal was to verify the reliability of the system when the patient cannot stand in the ideal position during the examination, i.e. in the centre of the calibration space. Results showed that detection of micromotion is not correlated to the position of markers inside the calibration space. The influence of different materials able to simulate human tissues, both hard and soft, on the data acquisition phase was also investigated. This additional exam was performed to assess whether the results obtained were similar also under as close as possible conditions to the clinical trials. Different experimental conditions were shown to not affect the acquisition phase of RSA procedure; markers were acquired with equal accuracy independently of tissues examined. Since the acquisition procedure is often performed by different operators, the difference between acquisitions made by different operators was compared. This study confirms the reliability of RSA and its accuracy, also in non-standard clinical setup and acquisition procedures. PMID:16139762

  6. Magnetic resonance imaging for in vivo assessment of three-dimensional patellar tracking.

    PubMed

    Fellows, R A; Hill, N A; Gill, H S; MacIntyre, N J; Harrison, M M; Ellis, R E; Wilson, D R

    2005-08-01

    We have developed a non-invasive measurement technique which can ultimately be used to quantify three-dimensional patellar kinematics of human subjects for a range of static positions of loaded flexion and assessed its accuracy. Knee models obtained by segmenting and reconstructing one high-resolution scan of the knee were registered to bone outlines obtained by segmenting fast, low-resolution scans of the knee in static loaded flexion. We compared patellar tracking measurements made using the new method to measurements made using Roentgen stereophotogrammetric analysis in three cadaver knee specimens loaded through a range of flexion in a test rig. The error in patellar spin and tilt measurements was less than 1.02 degrees and the error in lateral patellar shift was 0.88 mm. Sagittal plane scans provided more accurate final measurements of patellar spin and tilt, whereas axial plane scans provided more accurate measurements of lateral translation and patellar flexion. Halving the number of slices did not increase measurement error significantly, which suggests that scan times can be reduced without reducing accuracy significantly. The method is particularly useful for multiple measurements on the same subject because the high-resolution bone-models need only be created once; thus, the potential variability in coordinate axes assignment and model segmentation during subsequent measurements is removed. PMID:15958222

  7. Effect of skin movement artifact on knee kinematics during gait and cutting motions measured in vivo.

    PubMed

    Benoit, Daniel L; Ramsey, Dan K; Lamontagne, Mario; Xu, Lanyi; Wretenberg, Per; Renström, Per

    2006-10-01

    Eight healthy male subjects had intra-cortical bone-pins inserted into the proximal tibia and distal femur. Three reflective markers were attached to each bone-pin and four reflective markers were mounted on the skin of the tibia and thigh, respectively. Roentgen-stereophotogrammetric analysis (RSA) was used to determine the anatomical reference frame of the tibia and femur. Knee joint motion was recorded during walking and cutting using infrared cameras sampling at 120Hz. The kinematics derived from the bone-pin markers were compared with that of the skin-markers. Average rotational errors of up to 4.4 degrees and 13.1 degrees and translational errors of up to 13.0 and 16.1mm were noted for the walk and cut, respectively. Although skin-marker derived kinematics could provide repeatable results this was not representative of the motion of the underlying bones. A standard error of measurement is proposed for the reporting of 3D knee joint kinematics. PMID:16260140

  8. Migration of the humeral component of the Souter-Strathclyde elbow prosthesis: a long-term RSA study.

    PubMed

    van der Lugt, J C T; Valstar, E R; Witvoet-Braam, S W; Nelissen, R G H H

    2010-02-01

    Mechanical loosening which begins with early-onset migration of the prosthesis is the major reason for failure of the Souter-Strathclyde elbow replacement. In a prospective study of 18 Souter-Strathclyde replacements we evaluated the patterns of migration using roentgen stereophotogrammetric analysis. We had previously reported the short-term results after a follow-up of two years which we have now extended to a mean follow-up of 8.2 years (1 to 11.3). Migration was assessed along the co-ordinal axes and overall micromovement was expressed as the maximum total point movement. The alignment of the prosthesis and the presence of radiolucent lines were examined on conventional standardised radiographs. All the humeral components showed increased and variable patterns of migration at the extended follow-up and four humeral components were revised. The maximum total point movement at two years in the revised prostheses was 1.8 mm (sd 1.0) and in the non-revised 0.7 mm (sd 0.5, p = 0.01). Most humeral components migrated into external rotation resulting in an anterior and varus tilt. The ulnar components remained stable. PMID:20130315

  9. Recurrence of varus/valgus deformity after TKR at 3 years' follow-up.

    PubMed

    Russo, Alessandro; Bragonzoni, Laura; Trozzi, Claudia; Zaffagnini, Stefano; Neri, Maria Pia; Bruni, Danilo; Marcacci, Maurilio

    2008-01-01

    We assessed 30 patients with a cemented TKR implant (Interax ISA, Stryker Orthopaedics) at 1 and 3 years follow-up. We wanted to ascertain whether knee alignment was maintained during the critical period of follow-up in meniscal-bearing PCL-retaining TKR patients and test if correlations exist between alignment variations in the coronal plane and preoperative varus/valgus deformity or tibial component position and migration with respect to the tibia. Lower limb alignment was evaluated by measuring the angle between the tibia and femur anatomical axis directly from the antero-posterior radiographs and the tibial component position with respect to the tibial anatomical axis. The tibial component varus/valgus migration in the tibia was measured by roentgen stereophotogrammetric analysis. The results showed that at 3 years follow-up 40% of patients presented an alignment variation of over 3 degrees . The recurrent deformity was not correlated with the preoperative deformity, nor with the tibial component position with respect to the tibial shaft nor with its migration. After total knee arthroplasty coronal axial variation is a common finding and it depends on the overall limb muscles and ligaments adaptation to prosthetic constraints. PMID:18053725

  10. The effect of coordinate system choice and segment reference on RSA-based knee translation measures.

    PubMed

    Beardsley, Christina L; Paller, David J; Peura, Glenn D; Brattbakk, Bjarne; Beynnon, Bruce D

    2007-01-01

    Roentgen stereophotogrammetric analysis (RSA) can be utilized to accurately describe joint kinematics, but even when measuring small displacements within radiographically discernible structures, standardized reference frames are imperative for useful comparison across patients and across studies. In the current paper, accurately controlled laboratory models demonstrated the considerable influence that a mere 1.9-cm offset of the origin of the coordinate system from the rotation axes could exert on translation measures when rotations were occurring. In addition, the use of two different coordinate systems to gauge translation on a radiographic anterior-posterior (A-P) knee laxity exam resulted in a significant correlation (R(2)=0.562) between the two systems; however, differences of up 9.28 mm were found between corresponding measurements. This implies that clinical conclusions can potentially be upheld or refuted, based on the same data set, subject to coordinate system definition. Although the data analyzed presently involved the knee joint, similar issues surround the RSA motion analysis of other joints as well. PMID:16797021

  11. In vivo measurement of volumetric wear of a total knee replacement.

    PubMed

    Gill, H S; Waite, J C; Short, A; Kellett, C F; Price, A J; Murray, D W

    2006-08-01

    A new Roentgen Stereophotogrammetric Analysis (RSA) system is reported; it can measure penetration of the metallic femoral component of a Total Knee Replacement (TKR) prosthesis into the polyethylene bearing on the tibial component. This system was used to analyse a study group of six Anatomic Graduated Components (AGC) knee prostheses more than 6 years post-implantation, and to compare with a control group of six newly implanted AGC prostheses. The volumetric loss of polyethylene was estimated by imaging each prosthesis at a series of different knee flexion angles. The mean difference between the RSA measured polyethylene bearing thickness and the manufacturer's quoted values for the control group was -0.03 mm (SD 0.17). The estimated linear penetration at 6.4 years in this prosthesis was determined to be 0.1 mm/year. Volumetric wear was estimated to be 600-700 mm(3)/year at 6.4 years, equating to approximately 100 mm(3)/year. This does not appear to be clinically significant amount of wear as this prosthesis has excellent survival at 10 years. PMID:16784859

  12. Influence of cement viscosity and cement mantle thickness on migration of the Exeter total hip prosthesis.

    PubMed

    Nelissen, Rob G H H; Garling, Eric H; Valstar, Edward R

    2005-06-01

    The effect of bone cement viscosity and cement mantle thickness on the migration of the Exeter total hip prosthesis was studied in a prospective, randomized, double-blind clinical Roentgen Stereophotogrammetric Analysis study. Forty-one cemented total hip arthroplasty in 39 patients were included and randomized into a low/medium Simplex P cement group and a high-viscosity Simplex AF cement group. At time of stem introduction, 5 minutes after mixing, the Simplex AF was more viscous than Simplex P. No statistical difference existed between the 2 cement groups, for neither translation nor rotation migration data. Subsidence of the stem at 2-year follow-up was 1.1 +/- 0.56 mm for Simplex AF cement and 1.5 +/- 1.00 mm for Simplex P cement. The mean rotation of the acetabular components about the sagittal axis was 1.7 degrees +/- 3.8 degrees in the Simplex AF group and 0.7 degrees +/- 2.1 degrees for the Simplex P group. No effect of cement mantle thickness on migration of neither the acetabular cups nor the femoral stems was found. Although there were no differences in migration data for the cups and the stems, 2 acetabular cups in the Simplex AF group (almost 10%) were revised because of mechanical loosening. Because of these findings, we suggest caution before using this new high-viscosity bone cement for fixation of acetabular components. PMID:16124971

  13. Articular contact at the tibiotalar joint in passive flexion.

    PubMed

    Corazza, Federico; Stagni, Rita; Castelli, Vincenzo Parenti; Leardini, Alberto

    2005-06-01

    The knowledge of the contact areas at the tibiotalar articulating surfaces during passive flexion is fundamental for the understanding of ankle joint mobility. Traditional contact area reports are limited by the invasive measuring techniques used and by the complicated loading conditions applied. In the present study, passive flexion tests were performed on three anatomical preparations from lower leg amputation. Roentgen Stereophotogrammetric Analysis was used to accurately reconstruct the position of the tibia and the talus at a number of unconstrained flexion positions. A large number of points was collected on the surface of the tibial mortise and on the trochlea tali by a 3-D digitiser. Articular surfaces were modelled by thin plate splines approximating these points. Relative positions of these surfaces in all the flexion positions were obtained from corresponding bone position data. A distance threshold was chosen to define contact areas. A consistent pattern of contact was found on the articulating surfaces. The area moved anteriorly on both articular surfaces with dorsiflexion. The average position of the contact area centroid along the tibial mortise at maximum plantarflexion and at maximum dorsiflexion was respectively 58% posterior and 40% anterior of the entire antero-posterior length. For increasing dorsiflexion, the contact area moved from medial to lateral in all the specimens. PMID:15863104

  14. Technical factors affecting cup stability in bone impaction grafting.

    PubMed

    Bolder, S B T; Verdonschot, N; Schreurs, B W

    2007-01-01

    Favourable long-term clinical results can be achieved by the bone impaction technique in bone stock deficient acetabuli. Originally, firm impaction of manually prepared bone grafts using a rongeur was performed. An alternative technique for producing bone grafts is reaming from the pelvic wall or femoral head, which produces smaller-sized slurry bone grafts. These slurry grafts can be manually compressed in the bone defect using an acetabular reamer en reverse. In an artificial acetabular cavitary defect model both reconstruction techniques were compared in combination with a cemented cup. Mechanical testing was performed with a sequentially increasing dynamic load. Roentgen stereophotogrammetric analysis was used to determine initial cup stability. At all testing levels the initial stability of the cups reconstructed with slurry grafts and reversed reaming was significantly less in comparison to the original impaction technique. The original technique with firm impaction with a hammer and impactors of relatively large-sized bone grafts provides optimal initial stability. The reversed reaming technique of slurry grafts cannot be recommended for bone grafting of acetabular defects. PMID:17315771

  15. Accuracy of model-based RSA contour reduction in a typical clinical application.

    PubMed

    Hurschler, Christof; Seehaus, Frank; Emmerich, Judith; Kaptein, Bart L; Windhagen, Henning

    2008-08-01

    Marker-based roentgen stereophotogrammetric analysis (RSA) is an accurate method for measuring in vivo implant migration, which requires attachment of tantalum markers to the implant. Model-based RSA allows migration measurement without implant markers; digital pose estimation, which can be thought of as casting a shadow of a surface model of the implant into the stereoradiographs, is used instead. The number of surface models required in a given clinical study depends on the number of implanted sizes and design variations of prostheses. Contour selection can be used to limit pose estimation to areas of the prosthesis that do not vary with design, reducing the number of surface models required. The effect of contour reduction on the accuracy of the model-based method was investigated using three different contour selection schemes on tibial components in 24 patients at 3 and 6 month followup. The agreement interval (mean +/- 2 standard deviations), which bounds the differences between the marker-based and model-based methods with contour reduction was smaller than -0.028 +/- 0.254 mm. The data suggest that contour reduction does not result in unacceptable loss of model-based RSA accuracy, and that the model-based method can be used interchangeably with the marker-based method for measuring tibial component migration. PMID:18509712

  16. Changes in knee motion over the first 3 years with a mobile-bearing prosthesis.

    PubMed

    Russo, Alessandro; Montagna, Luisa; Bragonzoni, Laura; Visani, Andrea; Marcacci, Maurilio

    2006-08-01

    The present work aims to evaluate the mobility of the polyethylene bearing in 25 patients implanted with a mobile-bearing PCL-retaining TKR (Interax ISA, Striker Howmedica) under in vivo, weight-bearing conditions over 3 years' follow-up. We compared the bearing motion in response to specific tests in two consecutive follow-ups with Roentgen Stereophotogrammetric Analysis (RSA). Results showed that polyethylene continued to displace on the tibial baseplate over time: longitudinal rotations and medio-lateral translations tended to increase at the second follow-up (mean increases 0.7+/-2.5 degrees and 0.34+/-1.08 mm, respectively), while sagittal translations did not show any relevant change. Longitudinal rotations and AP translations were preserved when present at both follow-ups. Nevertheless, no statistical evidence of repeatable pattern of motion was found, since bearings frequently reversed their pattern of motion between the two follow-ups. The unconstrained polyethylene mobility resulted in an unrepeatable, erratic pattern of bearing motion intra-patient and over time. The changes in knee motion were found not to affect the clinical results over the first 3 years of follow-up. As in a fixed-bearing design, mobile-bearing design was not able to reproduce normal knee kinematics. PMID:16797995

  17. Status of ART-XC/SRG instrument

    NASA Astrophysics Data System (ADS)

    Pavlinsky, Mikhail

    Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in 2015 from Baikonur, by a Zenit rocket with a Fregat booster and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopes - a soft-x-ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules. The NASA Marshall Space Flight Center (MSFC) is fabricating the flight mirror modules for the ART-XC/SRG. Each mirror module will aligned with a focal plane CdTe double-sided strip detectors which will operate over the energy range of 6-30 keV, with an angular resolution of <1', a field of view of 34' and the expected energy resolution about 10% at 14 keV.

  18. The cooling concept of the x-ray telescope eROSITA

    NASA Astrophysics Data System (ADS)

    Fürmetz, Maria; Pfeffermann, Elmar; Predehl, Peter; Rohé, Christian; Tiedemann, Lars

    2008-07-01

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument of the Russian SRG satellite which will be launched in 2011 into an orbit of 600 km height and 30° inclination. It is being developed by the Max-Planck-Institute fur extraterrestrische Physik (MPE) in Garching, Germany. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The seven eROSITA CCD cameras require a stable operating temperature of about (-80+/-0,5)°C. Therefore the thermal control system is vitally important. The cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. By reason of the low-earth-orbit and the special scan geometry it is impossible for one radiator to look into the cold space at all times. The cameras and the radiators are connected by variable conductance heat pipes which can be cut off when a radiator gets too warm. A novel "latent cold storage unit" guarantees an absolute constant temperature without any further control mechanism.

  19. X-ray optic developments at NASA's MSFC

    NASA Astrophysics Data System (ADS)

    Atkins, C.; Ramsey, B.; Kilaru, K.; Gubarev, M.; O'Dell, S.; Elsner, R.; Swartz, D.; Gaskin, J.; Weisskopf, M.

    2013-05-01

    NASA's Marshall Space Flight Center (MSFC) has a successful history of fabricating optics for astronomical x-ray telescopes. In recent years optics have been created using electroforming replication for missions such as the balloon payload HERO (High energy replicated optics) and the rocket payload FOXSI (Focusing Optics x-ray Solar Imager). The same replication process is currently being used in the creation seven x-ray mirror modules (one module comprising of 28 nested shells) for the Russian ART-XC (Astronomical Rontgen Telescope) instrument aboard the Spectrum-Roentgen-Gamma mission and for large-diameter mirror shells for the Micro-X rocket payload. In addition to MSFC's optics fabrication, there are also several areas of research and development to create the high resolution light weight optics which are required by future x-ray telescopes. Differential deposition is one technique which aims to improve the angular resolution of lightweight optics through depositing a filler material to smooth out fabrication imperfections. Following on from proof of concept studies, two new purpose built coating chambers are being assembled to apply this deposition technique to astronomical x-ray optics. Furthermore, MSFC aims to broaden its optics fabrication through the recent acquisition of a Zeeko IRP 600 robotic polishing machine. This paper will provide a summary of the current missions and research and development being undertaken at NASA's MSFC.

  20. eROSITA in-orbit calibration strategy and plan: from the ground to the science

    NASA Astrophysics Data System (ADS)

    Freyberg, Michael J.; Dennerl, Konrad

    2012-09-01

    eROSITA is a German X-ray astronomical observatory on-board Spectrum-Roentgen-Gamma (SRG) with an expected launch in 2014 and operation at libration point L2. It consists of 7 identical mirror modules with 7 identical CCD cameras as focal plane instrumentation. It will observe the X-ray sky in the 0.25 - 10 keV range (4 yr all-sky survey, then pointed observations). Another instrument aboard SRG, ART-XC, will extend the spectral range to higher energies. We describe how the on-ground calibration is planned for the PANTER and PUMA X-ray test facilities, with respect to maximum scientific exploitation, in combination with an in-orbit calibration. This will be performed within one module and between the 7 eROSITA modules. If XMM-Newton will still be operational, a dedicated cross-calibration campaign is envisaged. The selection of the celestial targets and the procedure of the measurements with the internal Fe-55 calibration source are outlined.