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Sample records for friedrich aumayr hannspeter

  1. Dedication to Professor Hannspeter Winter (1941 2006): Dedication to Professor Hannspeter Winter (1941 2006)

    NASA Astrophysics Data System (ADS)

    McCullough, Bob

    2007-03-01

    Professor H Winter. It was with great sadness that we learnt of the death of colleague and friend Professor Hannspeter Winter in Vienna on the 8 November 2006. In memory of him and the contribution he made both to our conference and to the field of the physics of highly charged ions we dedicate these proceedings. Hannspeter was one of our distinguished invited speakers at HCI2006 and gave a talk on the status of the ITER programme. His invited paper on the subject is included in these proceedings. Hannspeter will be particularly remembered for his pioneering work on ion-surface interactions that, together with his colleagues at the Vienna University of Technology (TUW), has stimulated a worldwide experimental and theoretical interest in this field. He was appointed Director of the Institut fuer Allgemeine Physik at TUW in 1987 and using both his scientific and management skills has made it one of the leading university physics laboratories in the world. His research publications, of which there are 270, have inspired many others to work in the field of atomic and plasma physics. He was also a great European playing a major role in the EURATOM fusion programme, the European Physical Society and the International Union of Pure and Applied Physics and was an evaluator and advisory board member for many national and international institutions. Hannspeter was also an interesting and friendly social companion with interests in current affairs, music and fine wines and will be greatly missed both on a scientific and social level. Our condolences go to his wife Renate, son Dorian and his relatives. R W McCullough Co-chair HCI2006

  2. Carl Friedrich Gauss

    ERIC Educational Resources Information Center

    Rice, Kathryn; Scott, Paul

    2005-01-01

    This article presents a brief biography of Johann Carl Friedrich Gauss. Gauss was born on April 30, 1777, in the German city of Braunschweig (Brunswick). He was the only child of Gebhard Dietrich Gauss and Dorothea Benze. Neither of Gauss's parents had much education, his father could read and write, but earned his living doing menial jobs such as…

  3. Educational Theory as Topological Rhetoric: The Concepts of Pedagogy of Johann Friedrich Herbart and Friedrich Schleiermacher

    ERIC Educational Resources Information Center

    Kenklies, Karsten

    2012-01-01

    The debate concerning the relation of the theory of education and the practice of education is not new. In Germany, these discussions are an integral part of the development of educational science in the eighteenth century which is closely connected to Johann Friedrich Herbart and Friedrich Schleiermacher. Their concepts illustrate different…

  4. Friedrich Miescher and the discovery of DNA.

    PubMed

    Dahm, Ralf

    2005-02-15

    Over the past 60 years, DNA has risen from being an obscure molecule with presumed accessory or structural functions inside the nucleus to the icon of modern bioscience. The story of DNA often seems to begin in 1944 with Avery, MacLeod, and McCarty showing that DNA is the hereditary material. Within 10 years of their experiments, Watson and Crick deciphered its structure and yet another decade on the genetic code was cracked. However, the DNA story has already begun in 1869, with the young Swiss physician Friedrich Miescher. Having just completed his education as a physician, Miescher moved to Tübingen to work in the laboratory of biochemist Hoppe-Seyler, his aim being to elucidate the building blocks of life. Choosing leucocytes as his source material, he first investigated the proteins in these cells. However, during these experiments, he noticed a substance with unexpected properties that did not match those of proteins. Miescher had obtained the first crude purification of DNA. He further examined the properties and composition of this enigmatic substance and showed that it fundamentally differed from proteins. Due to its occurrence in the cells' nuclei, he termed the novel substance "nuclein"--a term still preserved in today's name deoxyribonucleic acid.

  5. Obituary: Ludwig Friedrich Oster, 1931-2003

    NASA Astrophysics Data System (ADS)

    Sofia, Sabatino; Altschuler, Martin D.

    2003-12-01

    Ludwig Friedrich Oster died at the Anchorage Nursing and Rehabilitation Center in Salisbury, MD on 28 February 2003, of complications from advanced Alzheimer's disease. He is survived by his wife Cheryl M. (Oroian) and his two children by a previous marriage, Ulrika and Mattias Oster. He had a distinguished career both as a researcher in solar physics and as a science administrator in the National Science Foundation. Ludwig was born on 8 March 1931 in Konstanz, Germany and emigrated to the U.S. in 1958, acquiring American citizenship in 1963. His mother and father were Emma Josefine (Schwarz) and Ludwig Friedrich Oster. He got a BS degree in physics at the University of Freiburg under the guidance of Prof. K. O. Kiepenheuer in 1951, and a MS (1954) and PhD from the University of Kiel in 1956 under the guidance of Prof. A. Unsold. From 1956 to 1958 he was a Fellow of the German Science Council at Kiel and, upon his arrival to the US in 1958, he became a Postdoctoral Research Associate in the Physics Department of Yale University. He became an Assistant Professor of Physics and Astrophysics at Yale in 1960 and five years later he was promoted to Associate Professor. In 1967 he became an Associate Professor of Physics and Astrophysics at the University of Colorado and a Fellow of the Joint Institute for Laboratory Astrophysics; he was promoted to Full Professor in 1970. In 1981 he was a Visiting Professor at Johns Hopkins University, and shortly thereafter became a National Research Council Senior Associate at NASA/Goddard Space Flight Center in Greenbelt, MD, where he worked on solar variability. He joined the National Science Foundation in 1983, where he became the Program Manager for the National Radio Astronomy Observatory in the Division of Astronomical Sciences of the Foundation; he remained there until his retirement in 1996. His early work, started in Germany and continued at Yale, concerned radiation mechanisms related to solar phenomena. His works on

  6. ["Item as Kaiser Friedrich's foot was amputated". The leg amputation of Kaiser Friedrich III on 8 June 1493 in Linz].

    PubMed

    Pangerl, Daniel Carlo

    2010-01-01

    The article deals with the amputation of emperor Friedrich III's left leg, which took place in Linz (Upper Austria) on June 8th 1493. This is one of the most famous and best documented surgical operations of the whole Middle Ages. The article offers a study about the two most important sources, i.e., the description of the amputation by the doctor Hans Seyff (Stuttgart, Württembergische Landesbibliothek, Cod. med. et phys. 20 8, fol. 71V-72V) and an anonymous painting (Wien, Graphische Sammlung Albertina, Min. 22475), followed by a detailed analysis of the amputation and an overview about the different types of doctors working at Friedrich's court.

  7. Stereotyping in "Damals war es Friedrich" and "Brandstiftung."

    ERIC Educational Resources Information Center

    Moffit, Gisela

    2000-01-01

    Discusses the use of young adult books in teaching high school and college-level German, particularly "Damals war es Friedrich" and "Brandstiftung." The didactic intentions of these books are to inform younger adults about the Nazi periods of the past and the Neo-nazi resurgence of the present, encourage them to confront the issues, and to take a…

  8. [God is dead--Friedrich Nietzsche's Oedipus complex].

    PubMed

    Wilkes, J

    1997-04-01

    The early psychoanalysts were influenced by the philosophical ideas of FRIEDRICH NIETZSCHE. The work of SIGMUND FREUD was partly based on NIETZSCHE'S literary world. Just before his mental disaster NIETZSCHE radically destroyed once precious ideals. The roots of this provocative development will be elucidated by analyzing NIETZSCHE'S childhood. A main aspect is NIETZSCHES close mother-tie and especially his father's early death. The father-image of NIETZSCHE'S late years is an essential of this paper. PMID:9206788

  9. Friedrich Nietzsche and his illness: a neurophilosophical approach to introspection.

    PubMed

    Perogamvros, Lampros; Perrig, Stephen; Bogousslavsky, Julien; Giannakopoulos, Panteleimon

    2013-01-01

    There are some arguments that Friedrich Nietzsche suffered from the autosomal dominant vascular microangiopathy: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL). Here, a hypothesis is formulated supporting that CADASIL presenting with symptoms of bipolar disorder and Gastaut-Geschwind syndrome would contribute to the increased insight and creativity of a philosopher whose perceptions and intuitions often bear out the results of modern neuroscience. Alterations of the brain default and reward networks would account for such an increased level of introspection and creativity. A new framework on approaching illness is proposed, which, in conformity with Nietzsche's positive view, outlines the enabling aspects of some otherwise highly disabling neuropsychiatric disorders.

  10. Friedrich Schwab: variable stars and bugs in Transylvania

    NASA Astrophysics Data System (ADS)

    Zsoldos, Endre

    2001-10-01

    Friedrich Schwab was born in Marburg and moved to Klausenburg, Transylvania when he was 21 years old (1879). He observed variable stars there, interrupted only to participate in the German transit-of-Venus expedition to Punta Arenas in the Strait of Magellan. Returning to Transylvania he became the University mechanic in Klausenburg, and continued the observations of variables. He left his post in 1891, and possibly went back to Germany. He is last heard of in 1918, when he was working in the Technische Schule in Ilmenau.

  11. Friedrich Möglich - sein Beitrag zum Aufbau der Physik in der DDR. Friedrich Möglich - langjähriger Mitherausgeber und Chefredakteur der Annalen der Physik

    NASA Astrophysics Data System (ADS)

    Rompe, Robert

    Friedrich Möglich, ein Schüler von Max von Laue und Erwin Schrödinger, übernahm 1947 die Chefredaktion der Annalen der Physik.Translated AbstractFriedrich Möglich - His Contributions to the Formation of Physics in GDRFriedrich Möglich a student of Max von Laue and Erwin Schrödinger took over as editor in chief of Annalen der Physik in 1947.

  12. [Space and medical market: Johann Friedrich Glaser's practice in Suhl].

    PubMed

    Schilling, Ruth

    2012-01-01

    The diary of the town and state physician Johann Friedrich Glaser (1707-1789) of Suhl enables us to reconstruct the area where he recruted his patients. A stream of visitors consulted him regularly. They often came from places where they had to travel at least two days in order to consult the physician. A visit in his house was therefore a decision consciously planned. A comparison of the sphere of Glaser's influence as a practitioner with the spheres of influence where his relatives (executioners and barber surgeons) lived shows how narrowly both were connected. Glaser's position on the medical market was very much influenced by his family network. The same picture can be obtained by analyzing the social spectrum of Glaser's patients, which is as manifold as the topographical indications, which one can draw from his diary. These do not give a systematic picture of the clients, which Glaser tried to gain, but are following communication channels established by his family network.

  13. Friedrich Nietzsche: the wandering and learned neuropath under Dionisius.

    PubMed

    Gomes, Marleide da Mota

    2015-11-01

    Friedrich Nietzsche (1844-1900) was a remarkable philologist-philosopher while remaining in a condition of ill-health. Issues about his wandering/disruptive behavior that might be a consequence and/or protection against his cognitive decline and multifaceted disease are presented. The life complex that raises speculations about its etiology is constituted by: insight, creativity and wandering behavior besides several symptoms and signs of disease(s), mainly neurological one. The most important issue to be considered at the moment is not the disease diagnosis (Lissauer's general paresis or CADASIL, e.g.), but the probable Nietzsche's great cognitive reserve linked to the multifactorial etiology (genetic and environmental), and shared characteristics both to creativity and psychopathology. This makes any disease seems especial regarding Nietzsche, and whichever the diagnostic hypothesis has to consider the Nietzsche's unique background to express any disease(s).

  14. Albert Einstein and Friedrich Dessauer: Political Views and Political Practice

    NASA Astrophysics Data System (ADS)

    Goenner, Hubert

    In this case study I compare the political views of the physicists Albert Einstein and Friedrich Dessauer between the first and second world wars, and I investigate their translation into concrete political practice. Both departed from their roles as experts in physics in favor of political engagement. The essence of Einstein's political practice seems to have been a form of political participation in exerting moral influence on people and organizations through public declarations and appeals in isolation from political mass movements. Dessauer exerted political influence both through public office (as a member of Parliament for the Catholic Center Party) and by acquiring a newspaper. The different political practice of both Einstein and Dessauer were unsuccessful in thwarting the Nazi takeover.

  15. Karl Friedrich Zollner and the historical dimension of astronomical photometry

    NASA Astrophysics Data System (ADS)

    Sterken, C.; Staubermann, K. B.

    This book results from presentations and discussions of a group of astronomers and historians during a one-day workshop held at Archenhold Observatory, Berlin-Treptow, on April 4, 1997. This meeting was the first forum in a series dedicated to historical aspects of observational astrophysics in the nineteenth and early twentieth century. The basic principle of these meetings is to reflect during one or more days on the work and personality of a single individual or of a group of persons, at the same time avoiding the really dominant figures that typify the age. By focusing on key people who epitomize a way of thinking and working that has formed many of the ideas by which we do astrophysical research today, we also attempt to evoke the scientific spirit of the era under consideration. In 1858, the German physicist Karl Friedrich Zoellner introduced a new type of astronomical photometer which became a bestseller in the second half of the nineteenth century and which led him to the first German professorship in astrophysics. His type of photometer allowed most accurate photometric measurements and was used at several observatories for almost half a century. This book outlines four major themes. The first part describes the observing instruments that were used by Zoellner and his contemporaries: photometers and spectrographs that complemented his original design, but also competed with his most versatile prototype photometer. The description also includes an account of technical aspects associated with the replication of such a photometer today. The second part analyses the astrophysical data that were obtained with Zoellner's tools, and extracts information hidden in the published data --- scientific information as well as diverse aspects related to the observer himself. These nineteenth-century data are now published for the first time on a modern magnitude scale and are directly accessible in tabular form, and are thus fully applicable to archeophotometric studies

  16. [Carl Friedrich von Weizsäcker - physicist and philosopher].

    PubMed

    Drieschner, Michael

    2014-01-01

    The subject of this paper is the philosopher Carl Friedrich von weizsäcker, especially under the aspect of the relation between physics and philosophy in his works. The decisive role of time in physics as well as in philosophy is described, and thereof is derived the comprehension of probability as a predicted relative frequency. Consequently quantum mechanics is interpreted as a theory of probability that uses "quantum logic" instead of classical propositional logic that is used in "normal" probability. The philosophical fruit of that is the interpretation of potentiality as the modality of the future. Weizsäcker's proposals for a justification of physics a priori are dealt with as well as his approach to a theory of "ur-objects", which are atoms in the strictest sense: q-bits.--Questions of Weizsäcker's personality are addressed: His role in the development of the nuclear reactor and atomic bomb in Nazi time, his enthusiasm and his religiousness as well as his efforts towards world peace.

  17. [Friedrich Mauz: T4 assessor and military psychiatrist].

    PubMed

    Silberzahn-Jandt, G; Schmuhl, H-W

    2012-03-01

    Friedrich Mauz is one of the medical perpetrators of the second tier whose biography is difficult to comprehend. Autobiographies from three different political systems exist - Weimar Republic, the Third Reich, and postwar Germany in which he constantly reinvented himself. While after 1933 he suddenly emphasized his participation in the civil war turmoil during the early period of the Weimar Republic and his patriotism, he then depicted himself after 1945 as an apolitical person characterized by Württemberg pietism who inwardly rejected the Nazi State but had found himself prepared to accept "all sorts of humiliating concessions." He claimed that he had always remained true to his scientific code of conduct and had distanced himself from psychiatric genetics. In point of fact, Mauz was among those exonerated in the denazification trial in 1946 and was able to pursue his career in the Federal Republic of Germany. However, if the sources are read against the grain, a different picture emerges. Mauz's career stalled in the 1930s, not because he had been politically offensive, but because his scientific work was flimsy and considered lacking originality, particularly since he had chosen constitution research and psychotherapy as his main fields of interest, which were overshadowed by research in genetic psychiatry in the 1930s. Mauz tendered his services to the Nazi policy of genetic health, served as a medical assessor in proceedings based on the "Law for the Prevention of Genetically Diseased Offspring," permitted himself to be recruited for the T4 program as a medical expert, even participated in the deliberations on a future "Law on Euthanasia," and as a consulting psychiatrist for the German Armed Forces contributed to military medicine. PMID:22399061

  18. Friedrich Wilhelm Bessel (1784-1846) and the Russian Astronomy

    NASA Astrophysics Data System (ADS)

    Ichsanova, Vera N.

    In the first half of the 19th century the foundations of stellar astronomy were established thanks to the German astronomer, geodeticist and mathematician Friedrich Wilhelm Bessel. Internationally estimed and in close relationship with scientists in many countries, especially in Russia, Bessel (although not yet 30 years old) in 1814 became a foreign member of the Petersburg Academy of Sciences. Wilhelm Struve, director of the Dorpat observatory, was in close contact with him. Together they discussed problems of observational procedures and the use of instruments. In 1817 Struve bought the same Reichenbach meridian circle as Bessel used in Königsberg. Both ordered their refractors from the famous Fraunhofer workshop in Munich. %(9-inch for Dorpat). Bessel was also involved in the high precision Russian geodetic survey which started in 1816 and which succeeded in connecting the Russian and western European triangulation networks. Struve tried to measure parallaxes using the bright star Vega (α Lyrae); his results were published in 1837. Also in 1837 Bessel, using his Fraunhofer heliometer and the star 61 Cygni, found a result close to modern values, later acknowledged with the Gold Medal of the Royal Astronomical Society. In 1834 Struve was named director of the new Russian observatory in Pulkovo, St. Petersburg. Struve discussed the plans with Bessel and both acquired a Repsold meridian circle. The next aim, begun in the 1840s -- after the first determination of stellar distances -- was the distribution of stars in space (in the Milky Way). For this, catalogues with not only accurate stellar positions but also brightnesses were necessary. Thanks to Bessel's thorough reformation of measuring and reduction methods, making possible high accuracy telescopic observations, Struve was able to produce important results in stellar astronomy.

  19. [Friedrich Mauz: T4 assessor and military psychiatrist].

    PubMed

    Silberzahn-Jandt, G; Schmuhl, H-W

    2012-03-01

    Friedrich Mauz is one of the medical perpetrators of the second tier whose biography is difficult to comprehend. Autobiographies from three different political systems exist - Weimar Republic, the Third Reich, and postwar Germany in which he constantly reinvented himself. While after 1933 he suddenly emphasized his participation in the civil war turmoil during the early period of the Weimar Republic and his patriotism, he then depicted himself after 1945 as an apolitical person characterized by Württemberg pietism who inwardly rejected the Nazi State but had found himself prepared to accept "all sorts of humiliating concessions." He claimed that he had always remained true to his scientific code of conduct and had distanced himself from psychiatric genetics. In point of fact, Mauz was among those exonerated in the denazification trial in 1946 and was able to pursue his career in the Federal Republic of Germany. However, if the sources are read against the grain, a different picture emerges. Mauz's career stalled in the 1930s, not because he had been politically offensive, but because his scientific work was flimsy and considered lacking originality, particularly since he had chosen constitution research and psychotherapy as his main fields of interest, which were overshadowed by research in genetic psychiatry in the 1930s. Mauz tendered his services to the Nazi policy of genetic health, served as a medical assessor in proceedings based on the "Law for the Prevention of Genetically Diseased Offspring," permitted himself to be recruited for the T4 program as a medical expert, even participated in the deliberations on a future "Law on Euthanasia," and as a consulting psychiatrist for the German Armed Forces contributed to military medicine.

  20. Carl Friedrich Gauss - General Theory of Terrestrial Magnetism - a revised translation of the German text

    NASA Astrophysics Data System (ADS)

    Glassmeier, K.-H.; Tsurutani, B. T.

    2014-02-01

    This is a translation of the Allgemeine Theorie des Erdmagnetismus published by Carl Friedrich Gauss in 1839 in the Resultate aus den Beobachtungen des Magnetischen Vereins im Jahre 1838. The current translation is based on an earlier translation by Elizabeth Juliana Sabine published in 1841. This earlier translation has been revised, corrected, and extended. Numerous biographical comments on the scientists named in the original text have been added as well as further information on the observational material used by Carl Friedrich Gauss. An attempt is made to provide a readable text to a wider scientific community, a text laying the foundation of today's understanding of planetary magnetic fields.

  1. The Neo-Humanistic Concept of "Bildung" Going Astray: Comments to Friedrich Schiller's Thoughts on Education

    ERIC Educational Resources Information Center

    Vinterbo-Hohr, Aagot; Hohr, Hansjorg

    2006-01-01

    Friedrich Schiller (1759-1805), German poet, dramatist, philosopher and publisher, was a prominent contributor to the educational neo-humanistic concept of Bildung at the threshold to Romanticism. Schiller assigns a pivotal role to the aesthetic education arguing that aesthetic activity reconciles sensuousness and reason and thereby creates the…

  2. A Reflective Conversation with Terry Friedrichs on Teaching Academics to Gifted Students with Asperger Syndrome

    ERIC Educational Resources Information Center

    Friedrichs, Terence Paul; Shaughnessy, Michael F.

    2015-01-01

    In this reflective interview with Terry Friedrichs--a hands-on academic-learning specialist and researcher with gifted students with Asperger Syndrome--he defines these pupils, describes their "straightforward" and confusing traits, and recounts his initial and later instructional experiences with them over several decades. The piece…

  3. "Dancing Cannot Start Too Soon": Spiritual Education in the Thought of Jean Paul Friedrich Richter

    ERIC Educational Resources Information Center

    Pridmore, John

    2004-01-01

    Johann Paul Friedrich Richter (1763-1825) adopted the pen-name "Jean Paul" in honour of Jean Jaques Rousseau. His "Levana or the doctrine of education" ("Levana oder Erziehlehre") was once a standard text and required reading in teacher education. Outside Germany the name of Jean Paul is now little known and the seminal educational text for which…

  4. Two Rival Conceptions of Vocational Education: Adam Smith and Friedrich List.

    ERIC Educational Resources Information Center

    Winch, Christopher

    1998-01-01

    Examines and discusses two views of political economy: (1) the classical model of Adam Smith; and (2) the social capitalist model associated with Friedrich List. Explores two varieties of vocational education and training that emerge from a comparison of Smith's and List's ideas. (CMK)

  5. Friedrich Froebel's Gifts: Connecting the Spiritual and Aesthetic to the Real World of Play and Learning

    ERIC Educational Resources Information Center

    Provenzo, Eugene F., Jr.

    2009-01-01

    Friedrich Froebel, the German educator and founder of the Kindergarten Movement, developed a series of play materials including geometric building blocks and pattern activity blocks designed to teach children about forms and relationships found in nature. Froebel's notions about using activity and play in preschool education complement many…

  6. [Friedrich Nietzsche: history of his illness. On the 100th anniversary of the death of the poet-philosopher].

    PubMed

    Wilkes, J

    2000-04-01

    The philosopher Friedrich Nietzsche was one of the most famous patients in the psychiatric hospital Jena. Between 1889 and 1890, Otto Binswanger und Theodor Ziehen treated the progressive paralysis of Friedrich Nietzsche whose 100th anniversary of death is on 25th August 2000. After Nietzsche's death, an animated discussion about his disease arose. Many objected against the syphilitic diagnosis of the disease. Nietzsche's medical fill became a popular object of science, although it ended as a very odd story.

  7. [Carl Friedrich von Weizsäcker's philosophy of the mind].

    PubMed

    Lyre, Holger

    2014-01-01

    The paper deals with Carl Friedrich von Weizsäcker's position within the philosophy of mind. It turns out that Weizsäcker's ontology is based on an unorthodox conception both in the philosophy of physics and in the philosophy of mind. His quantum information theoretic reductionism is based on a subtle combination of atomism and holism, his philosophy of mind connected to this is a neutral monism, which proposes a bold intertwining of mind, matter, and space.

  8. [Carl Friedrich von Weizsäcker's philosophy of the mind].

    PubMed

    Lyre, Holger

    2014-01-01

    The paper deals with Carl Friedrich von Weizsäcker's position within the philosophy of mind. It turns out that Weizsäcker's ontology is based on an unorthodox conception both in the philosophy of physics and in the philosophy of mind. His quantum information theoretic reductionism is based on a subtle combination of atomism and holism, his philosophy of mind connected to this is a neutral monism, which proposes a bold intertwining of mind, matter, and space. PMID:24974603

  9. Werner Heisenberg and Carl Friedrich Freiherr von Weizsäcker: A Fifty-Year Friendship*

    NASA Astrophysics Data System (ADS)

    Cassidy, David C.

    2015-03-01

    This paper follows Werner Heisenberg and Carl Friedrich von Weizsäcker during their fifty-year friendship from 1926, when they first met in Copenhagen, to Heisenberg's death in Munich in 1976. The relationship underwent profound changes during that period, as did physics, philosophy, and German society and politics, all of which exerted important influences on their lives, work, and interactions with each other. The nature of these developments and their impact are explored in this paper.

  10. ["Living with the bomb" - Carl Friedrich von Weizsäcker's path from physics to politics].

    PubMed

    Walker, Mark

    2014-01-01

    Carl Friedrich von Weizsäcker spanned a spectrum from physics to politics, with philosophy in-between. This chapter surveys the most controversial part of his career, including his work on nuclear weapons and participation in cultural propaganda during the Second World War, his subsequent active political engagement during the postwar Federal German Republic, in particular the role of nuclear weapons, and his participation in myths surrounding Hitler's Bomb".

  11. [Friedrich Trendelenburg 1844-1924: a tribute on his 150th birthday].

    PubMed

    Schwokowski, C F

    1994-01-01

    Life and scientific work of Friedrich Trendelenburg are gratefully appreciated on the occasion of his 150th birthday. The education by his parents, the great impressions gained during a visit in Scotland as a young man and the molding influence of his academic teacher v. Langenbeck are presented. There was only a short time when he was the head of the surgical department of the Friedrichhain Hospital in Berlin, because his real aim was an academic career. In the presented paper his famous merits in science and practical work as well as his enormous aura as the director of the surgical departments of the universities of Rostock, Bonn and Leipzig are described. Trendelenburg was an always strictly scientifically acting surgeon. His technical inventions and new operative procedures were of high value with a worldwide acknowledgement. Objectivity, modesty and human grandeur were the eminent characteristics of this hero of surgery who never looked for personal appreciation but always got it.

  12. [Carl Friedrich von Weizsäcker's design of a unity of physics].

    PubMed

    Görnitz, Thomas

    2014-01-01

    As I learned in many conversations with Carl Friedrich von Weizsäcker, he saw his place in the history of science deriving from his "Theory of Urs". This theory will establish the unity of science on the basis of quantum bits. Any attempts to find some "fundamental bricks"--of whatever kind--must fail because of the antinomies of atomism. An abstract quantum bit is a structure quantum that cannot be conceived as a particle in space and time. However, it is clear, solely for logical reasons, that a quantum bit is an ultimate and indecomposable entity. Weizsäcker's revolutionary goal was--already 50 years ago--to unite quantum theory with cosmology and, on these grounds, proceed to a theory of elementary particles. The article gives a short overview of Weizsäcker's approach to the unity of physics, ending with a brief summary of what has been achieved in that endeavour up to now.

  13. Vital forces and organization: philosophy of nature and biology in Karl Friedrich Kielmeyer.

    PubMed

    Gambarotto, Andrea

    2014-12-01

    The historical literature on German life science at the end of the 18th century has tried to rehabilitate eighteenth century vitalism by stressing its difference from Naturphilosophie. Focusing on the work of Karl Friedrich Kielmeyer this paper argues that these positions are based on a historiographical bias and that the clear-cut boundary between German vitalism and Naturphilosophie is historically unattested. On the contrary, they both belong to the process of conceptual genealogy that contributed to the project of a general biology. The latter emerged as the science concerned with the laws that regulate the organization of living nature as a whole. The focus on organization was, at least partially, the result of the debate surrounding the notion of "vital force", which originated in the mid-eighteenth century and caused a shift from a regulative to a constitutive understanding of teleology. PMID:25168014

  14. [Friedrich Trendelenburg 1844-1924: a tribute on his 150th birthday].

    PubMed

    Schwokowski, C F

    1994-01-01

    Life and scientific work of Friedrich Trendelenburg are gratefully appreciated on the occasion of his 150th birthday. The education by his parents, the great impressions gained during a visit in Scotland as a young man and the molding influence of his academic teacher v. Langenbeck are presented. There was only a short time when he was the head of the surgical department of the Friedrichhain Hospital in Berlin, because his real aim was an academic career. In the presented paper his famous merits in science and practical work as well as his enormous aura as the director of the surgical departments of the universities of Rostock, Bonn and Leipzig are described. Trendelenburg was an always strictly scientifically acting surgeon. His technical inventions and new operative procedures were of high value with a worldwide acknowledgement. Objectivity, modesty and human grandeur were the eminent characteristics of this hero of surgery who never looked for personal appreciation but always got it. PMID:7846962

  15. [Carl Friedrich von Weizsäcker and the Bethe-Weizsäcker cycle].

    PubMed

    Wiescher, Michael

    2014-01-01

    The Carbon- or Bethe-Weizsäcker Cycle plays an important role in astrophysics as one of the most important energy sources for a quiescent and explosive hydrogen burning in stars. This paper presents the historical background and the contributions by Carl Friedrich von Weizsäcker and Hans Bethe who provided the first predictions of the cycle. Furthermore, it discussed the experimental verification of the predicted process in the following decades. Also discussed is the extension of the initial Carbon cycle to the CNO multi-cycles and the hot CNO cycles which followed from the detailed experimental studies of the associated nuclear reactions. Finally discussed is the impact of the experimental and theoretical results on our present understanding of hydrogen burning in different stellar environments and on our understanding of the chemical evolution of our universe. PMID:24974598

  16. [Friedrich Nietzsche: life and work in the struggle against his suffering].

    PubMed

    Kaiser, Otto

    2005-01-01

    This paper examines the connection between the life, sense of mission and suffering in the work of Friedrich Nietzsche. It shows that, as early as his Basel years, he wanted to become a philosopher who was willing to transmit without fear what he considered to be true to everybody, even if he would have to suffer and remain unappreciated. He was afflicted with increasing numbers of headaches and bouts of nausea from the mid-1870s and was further handicapped by constantly deteriorating vision. The ten years before his breakdown were spent as a traveller searching for a place where his suffering could be eased. The isolation imposed on him by the illness gave him the inner freedom to break the old certainties and to offer a new myth as an alternative. His failure as a writer was compensated by an intensified and, finally, gross sense of mission which ended in mental derangement in early January 1889.

  17. [Carl Friedrich von Weizsäcker and the Bethe-Weizsäcker cycle].

    PubMed

    Wiescher, Michael

    2014-01-01

    The Carbon- or Bethe-Weizsäcker Cycle plays an important role in astrophysics as one of the most important energy sources for a quiescent and explosive hydrogen burning in stars. This paper presents the historical background and the contributions by Carl Friedrich von Weizsäcker and Hans Bethe who provided the first predictions of the cycle. Furthermore, it discussed the experimental verification of the predicted process in the following decades. Also discussed is the extension of the initial Carbon cycle to the CNO multi-cycles and the hot CNO cycles which followed from the detailed experimental studies of the associated nuclear reactions. Finally discussed is the impact of the experimental and theoretical results on our present understanding of hydrogen burning in different stellar environments and on our understanding of the chemical evolution of our universe.

  18. Professor Bernhard Pollack (1865-1928) of Friedrich Wilhelm University, Berlin: neurohistologist, ophthalmologist, pianist.

    PubMed

    Triarhou, Lazaros C

    2012-01-01

    This article highlights the life and work of Bernhard Pollack (1865-1928), a pioneer neurohistologist, ophthalmologist, and world-class pianist. In 1897, Pollack published the first standard manual on staining methods for the nervous system. Born into a Prussian-Jewish family, he received his piano education from the composer Moritz Moszkowski and his pathology education from Carl Weigert. Pollack worked in the Institutes of Wilhelm Waldeyer (anatomy), Emanuel Mendel (neuropsychiatry), the later Nobel laureate Robert Koch (infectious diseases), and the Eye Policlinic of Paul Silex (ophthalmology), becoming a Professor of Ophthalmology at Berlin's Friedrich-Wilhelms-Universität in 1919. The study also chronicles the founding by Pollack of the Berlin Doctors' Orchestra in 1911. PMID:22572721

  19. Carl Friedrich Richard Foerster (1825-1902) - the inventor of perimeter and photometer.

    PubMed

    Grzybowski, Andrzej; Sobolewska, Bianka

    2015-09-01

    Carl Friedrich Richard Foerster (1825-1902) was a German who was born in the Polish city Leszno. He studied medicine at the Medical Faculty of Breslau (now Wroclaw, Poland) University, and later in Heidelberg and Berlin. From 1855, he worked in Breslau, where he established in 1857 the first ophthalmology clinic. Later, he became a professor in ophthalmology, the first director of the Department of Ophthalmology at the University of Breslau, and even the rector of this University. Forster did many pioneering works on visual fields, invented a photometer and the first perimeter, known for many years as the Foerster perimeter. Moreover, he studied night blindness, visual field changes due to different pathologies, and many eye diseases, including glaucoma, cataract, retinal and choroidal diseases.

  20. Vital forces and organization: philosophy of nature and biology in Karl Friedrich Kielmeyer.

    PubMed

    Gambarotto, Andrea

    2014-12-01

    The historical literature on German life science at the end of the 18th century has tried to rehabilitate eighteenth century vitalism by stressing its difference from Naturphilosophie. Focusing on the work of Karl Friedrich Kielmeyer this paper argues that these positions are based on a historiographical bias and that the clear-cut boundary between German vitalism and Naturphilosophie is historically unattested. On the contrary, they both belong to the process of conceptual genealogy that contributed to the project of a general biology. The latter emerged as the science concerned with the laws that regulate the organization of living nature as a whole. The focus on organization was, at least partially, the result of the debate surrounding the notion of "vital force", which originated in the mid-eighteenth century and caused a shift from a regulative to a constitutive understanding of teleology.

  1. Floquet resonant states and validity of the Floquet-Magnus expansion in the periodically driven Friedrichs models

    NASA Astrophysics Data System (ADS)

    Mori, Takashi

    2015-02-01

    The Floquet eigenvalue problem is analyzed for periodically driven Friedrichs models on discrete and continuous space. In the high-frequency regime, there exists a Floquet bound state consistent with the Floquet-Magnus expansion in the discrete Friedrichs model, while it is not the case in the continuous model. In the latter case, however, the bound state predicted by the Floquet-Magnus expansion appears as a metastable state whose lifetime diverges in the limit of large frequencies. We obtain the lifetime by evaluating the imaginary part of the quasienergy of the Floquet resonant state. In the low-frequency regime, there is no Floquet bound state and instead the Floquet resonant state with exponentially small imaginary part of the quasienergy appears, which is understood as the quantum tunneling in the energy space.

  2. [Carl Friedrich von Weizsäcker's language, rhetoric and habitus].

    PubMed

    Hentschel, Klaus

    2014-01-01

    Carl Friedrich von Weizsäcker was not only an exceptional physicist, philosopher and peace scholar, but also a skilled and articulate speaker and a highly successful author. Dozens of his books were published in tens of thousands of copies despite their highly nontrivial content. This wide impact was only possible--this at least is one of the claims made in this paper--because of his sophisticated style and rhetorics. The analysis here is based on hand-picked samples from all kinds of Weizsäcker texts (talks, scientific and popular papers and books, poems and Limericks). Strangely enough, this interesting stylistic and rhetorical facet of his oeuvre has hitherto not been analyzed in any detail despite its crucial importance in the broad impact on his multifarious audience. My paper starts out from a collection of striking features of his language and structural specialties in his published talks and speeches, and explore findings from sound recordings and film tapes which offer further insight into his manner of emphasis, usage of pauses and intonation. On the basis of these stylistic traits and their often subcutaneous, but nevertheless clever rhetorics, I close with a few remarks on the habitus of this scholar and his positioning within the ensemble of German-speaking physicists of that generation.

  3. Vitalism and synthesis of urea. From Friedrich Wöhler to Hans A. Krebs.

    PubMed

    Kinne-Saffran, E; Kinne, R K

    1999-01-01

    In 1828, Friedrich Wöhler, a German physician and chemist by training, published a paper that describes the formation of urea, known since 1773 to be a major component of mammalian urine, by combining cyanic acid and ammonium in vitro. In these experiments the synthesis of an organic compound from two inorganic molecules was achieved for the first time. These results weakened significantly the vitalistic hypothesis on the functioning of living cells, although Wöhler, at that time, was more interested in the chemical consequences of isomerism than in the philosophical implications of his finding. However, the chemical synthesis observed by Wöhler does not represent the reaction which is employed in the mammalian liver for urea synthesis. The mechanism of this process was elucidated by the German physician Hans A. Krebs and his medical student Kurt Henseleit in 1932 and was shown to include the ornithine cycle. This 'urea cycle' is only observed in living cells; this apparently vitalistic phenomenon is caused by the compartmentalization of the various enzymatic reactions in mitochondria and cytosol, respectively. PMID:10213830

  4. Model building with wind and water: Friedrich Ahlborn's photo-optical flow analysis.

    PubMed

    Hinterwaldner, Inge

    2015-02-01

    Around 1900, several experimenters investigated turbulences in wind tunnels or water basins by creating visualizations. One of them, the German zoologist Friedrich Ahlborn (1858-1937), was familiar with the works by his contemporaries but he struck a new path. He combined three different kinds of photographs taken at the same time and showed the same situation in his water trough-but each in a different way. With this first basic operation, Ahlborn heuristically opened up a previously non-existent space for experimentation, analysis, and recombination. He generated an astonishing diversity of information by adopting the tactics of 'inversions' in which he interpreted one part of the experimental setup, or its results, in different ways. Between the variants of the 'autographs' which he developed, he defined areas of intersection to be able to translate results from individual records into each other. To this end, Ahlborn created other sets of visual artifacts such as drawn diagrams, three-dimensional wire frame constructions, and clay reliefs. His working method can be described as a cascading array of successive modeling steps, as elaborated by Eric Winsberg (1999), or of inscriptions in Bruno Latour's words (Latour, 1986). By examining Ahlborn's procedures closely we propose conceptualizations for the experimenter's various operations. PMID:26109406

  5. [Carl Friedrich von Weizsäcker and the interpretations of quantum theory].

    PubMed

    Stöckler, Manfred

    2014-01-01

    What are 'interpretations' of quantum theory? What are the differences between Carl Friedrich von Weizsäkcker's approach and contemporary views? The various interpretations of quantum mechanics give diverse answers to questions concerning the relation between measuring process and standard time development, the embedding of quantum objects in space ('wave-particle-dualism'), and the reference of state vectors. Does the wave function describe states in the real world or does it refer to our knowledge about nature? First, some relevant conceptions in Weizsäcker's book The Structure of Physics (Der Aufbau der Physik, 1985) are introduced. In a second step I point out why his approach is not any longer present in contemporary debates. One reason is that Weizsäcker is mainly affected by classical philosophy (Platon, Aristoteles, Kant). He could not esteem the philosophy of science that was developed in the spirit of logical empiricism. So he lost interest in disputes with Anglo-Saxon philosophy of quantum mechanics. Especially his interpretation of probability and his analysis of the collapse of the state function as change in knowledge differ from contemporary standard views. In recent years, however, epistemic interpretations of quantum mechanics are proposed that share some of Weizsäcker's intuitions.

  6. Friedrich Albert Lange on neo-Kantianism, socialist Darwinism, and a psychology without a soul.

    PubMed

    Teo, Thomas

    2002-01-01

    Friedrich Albert Lange was a German philosopher, political theorist, educator, and psychologist who outlined an objective psychology in the 1860s. This article shows how some of the most important worldviews of the nineteenth century (Kantianism, Marxism, and Darwinism) were combined creatively in his thought system. He was crucial in the development of neo-Kantianism and incorporated psycho-physiological research on sensation and perception in order to defend Kant's epistemological idealism. Based on a critique of phrenology and philosophical psychology of his time, Lange developed a program of a psychology without a soul. He suggested that only those phenomena that can be observed and controlled should be studied, that psychology should focus on actions and speech, and that for each psychological event the corresponding physical or physiological processes should be identified. Lange opposed introspection and subjective accounts and promoted experiments and statistics. He also promoted Darwinism for psychology while developing a socialist progressive-democratic reading of Darwin in his social theory. The implications of socialist Darwinism on Lange's conceptualization of race are discussed and his prominence in nineteenth century philosophy and psychology is summarized.

  7. [Carl Friedrich von Weizsäcker's language, rhetoric and habitus].

    PubMed

    Hentschel, Klaus

    2014-01-01

    Carl Friedrich von Weizsäcker was not only an exceptional physicist, philosopher and peace scholar, but also a skilled and articulate speaker and a highly successful author. Dozens of his books were published in tens of thousands of copies despite their highly nontrivial content. This wide impact was only possible--this at least is one of the claims made in this paper--because of his sophisticated style and rhetorics. The analysis here is based on hand-picked samples from all kinds of Weizsäcker texts (talks, scientific and popular papers and books, poems and Limericks). Strangely enough, this interesting stylistic and rhetorical facet of his oeuvre has hitherto not been analyzed in any detail despite its crucial importance in the broad impact on his multifarious audience. My paper starts out from a collection of striking features of his language and structural specialties in his published talks and speeches, and explore findings from sound recordings and film tapes which offer further insight into his manner of emphasis, usage of pauses and intonation. On the basis of these stylistic traits and their often subcutaneous, but nevertheless clever rhetorics, I close with a few remarks on the habitus of this scholar and his positioning within the ensemble of German-speaking physicists of that generation. PMID:24974596

  8. Vitalism and synthesis of urea. From Friedrich Wöhler to Hans A. Krebs.

    PubMed

    Kinne-Saffran, E; Kinne, R K

    1999-01-01

    In 1828, Friedrich Wöhler, a German physician and chemist by training, published a paper that describes the formation of urea, known since 1773 to be a major component of mammalian urine, by combining cyanic acid and ammonium in vitro. In these experiments the synthesis of an organic compound from two inorganic molecules was achieved for the first time. These results weakened significantly the vitalistic hypothesis on the functioning of living cells, although Wöhler, at that time, was more interested in the chemical consequences of isomerism than in the philosophical implications of his finding. However, the chemical synthesis observed by Wöhler does not represent the reaction which is employed in the mammalian liver for urea synthesis. The mechanism of this process was elucidated by the German physician Hans A. Krebs and his medical student Kurt Henseleit in 1932 and was shown to include the ornithine cycle. This 'urea cycle' is only observed in living cells; this apparently vitalistic phenomenon is caused by the compartmentalization of the various enzymatic reactions in mitochondria and cytosol, respectively.

  9. [Carl Friedrich von Weizsäcker and the interpretations of quantum theory].

    PubMed

    Stöckler, Manfred

    2014-01-01

    What are 'interpretations' of quantum theory? What are the differences between Carl Friedrich von Weizsäkcker's approach and contemporary views? The various interpretations of quantum mechanics give diverse answers to questions concerning the relation between measuring process and standard time development, the embedding of quantum objects in space ('wave-particle-dualism'), and the reference of state vectors. Does the wave function describe states in the real world or does it refer to our knowledge about nature? First, some relevant conceptions in Weizsäcker's book The Structure of Physics (Der Aufbau der Physik, 1985) are introduced. In a second step I point out why his approach is not any longer present in contemporary debates. One reason is that Weizsäcker is mainly affected by classical philosophy (Platon, Aristoteles, Kant). He could not esteem the philosophy of science that was developed in the spirit of logical empiricism. So he lost interest in disputes with Anglo-Saxon philosophy of quantum mechanics. Especially his interpretation of probability and his analysis of the collapse of the state function as change in knowledge differ from contemporary standard views. In recent years, however, epistemic interpretations of quantum mechanics are proposed that share some of Weizsäcker's intuitions. PMID:24974602

  10. Model building with wind and water: Friedrich Ahlborn's photo-optical flow analysis.

    PubMed

    Hinterwaldner, Inge

    2015-02-01

    Around 1900, several experimenters investigated turbulences in wind tunnels or water basins by creating visualizations. One of them, the German zoologist Friedrich Ahlborn (1858-1937), was familiar with the works by his contemporaries but he struck a new path. He combined three different kinds of photographs taken at the same time and showed the same situation in his water trough-but each in a different way. With this first basic operation, Ahlborn heuristically opened up a previously non-existent space for experimentation, analysis, and recombination. He generated an astonishing diversity of information by adopting the tactics of 'inversions' in which he interpreted one part of the experimental setup, or its results, in different ways. Between the variants of the 'autographs' which he developed, he defined areas of intersection to be able to translate results from individual records into each other. To this end, Ahlborn created other sets of visual artifacts such as drawn diagrams, three-dimensional wire frame constructions, and clay reliefs. His working method can be described as a cascading array of successive modeling steps, as elaborated by Eric Winsberg (1999), or of inscriptions in Bruno Latour's words (Latour, 1986). By examining Ahlborn's procedures closely we propose conceptualizations for the experimenter's various operations.

  11. [The Great European Georg Friedrich Nicolai: physician and pacifist. Berlin, Germany, 1874 - Santiago, Chile, 1964].

    PubMed

    Cabello C, Felipe

    2013-04-01

    Georg Friedrich Nicolai (1874-1964) was a German physician and physiologist whose pacifism during the First World War led him in 1914 to cosign with W. J. Foerster, A. Einstein and O. Bueck a "Manifesto to the Europeans" against the entry of Germany into the war and the invasion of Belgium. As a result of this appeal and his strong pacifism, Nicolai lost his positions as cardiologist to the German royal family, professor at the University of Berlin and chief of laboratory at the Charite hospital also in Berlin, and was sent as a garrison physician in Graundenz, in today's Poland. There he began to write his book, The Biology of War. It managed to avoid censorship and was published in Leipzig in 1916. He was court-martialed in Danzig in 1916 but escaped to Denmark. Nicolai was reinstated to his faculty positions by the Weimar Republic after the war but was subsequently forced to emigrate from Germany to South America by the pressure of right wing student groups who accused him of being a deserter and a traitor. From 1922 to 1932 Nicolai lived in Argentina, and from 1932 until his death in 1964, in Chile. In this later country Nicolai was professor in the University of Chile and interacted with members of the Chilean intelligentsia, including the poets Vicente Huidobro, Gonzalo Rojas and Pablo Neruda. Through his friendship with Chilean psychiatrist Agustin Tellez, Nicolai influenced the development of phenomenological psychiatric school in Chile. The Chilean novelist Fernando Alegria compared him favorably with Robert J. Oppenheimer and Linus Pauling. PMID:23900377

  12. [Carl Friedrich von Weizsäcker: nuclear disarmament and the search for freedom].

    PubMed

    Neuneck, Götz

    2014-01-01

    Carl Friedrich von Weizsäcker's comprehensive contributions to nuclear disarmament and arms control, as well as his peace policy impulses are to be understood primarily in the context of his family origin, his comprehensive thinking and the historical circumstances of the emerging nuclear age. They have a scientific, political and a strong philosophical-moral component. Beside the factual problems (nuclear energy, military strategy) he was interested in political power issues and their ambivalence and perception. His actual work is not only based on general academic knowledge, but also serve the immediate political influence on a scientific basis. Weizsäcker was not committed to nuclear disarmament or arms control per se, but about creating a lasting peace policy in the nuclear age. The paper discusses in chronological order of Weizsäcker's work within the policy field peace and disarmament. Family origin, study and work on the nuclear programme by Nazi-Germany laid the foundations for his later career. As a young physicist, he was directly involved in the political and ethical dilemma of the military and civilian use of nuclear energy. After the war, in Göttingen and Hamburg the reflections of the Nazi phase and the discussion of ways out of the dangers of the Cold War followed. The Max-Planck Institute in Starnberg dealt with the science-based treatment of global world problems, including the dangers of nuclear proliferation. Finally, Weizsäcker initiated a Peace Council in 1985. He urged both the perception of the moral responsibility of scientists as well as an ethics of the scientific-technological age. According to him, a general and profound change in the consciousness of humankind is needed to solve the existing power problems and the problem of war.

  13. [The Great European Georg Friedrich Nicolai: physician and pacifist. Berlin, Germany, 1874 - Santiago, Chile, 1964].

    PubMed

    Cabello C, Felipe

    2013-04-01

    Georg Friedrich Nicolai (1874-1964) was a German physician and physiologist whose pacifism during the First World War led him in 1914 to cosign with W. J. Foerster, A. Einstein and O. Bueck a "Manifesto to the Europeans" against the entry of Germany into the war and the invasion of Belgium. As a result of this appeal and his strong pacifism, Nicolai lost his positions as cardiologist to the German royal family, professor at the University of Berlin and chief of laboratory at the Charite hospital also in Berlin, and was sent as a garrison physician in Graundenz, in today's Poland. There he began to write his book, The Biology of War. It managed to avoid censorship and was published in Leipzig in 1916. He was court-martialed in Danzig in 1916 but escaped to Denmark. Nicolai was reinstated to his faculty positions by the Weimar Republic after the war but was subsequently forced to emigrate from Germany to South America by the pressure of right wing student groups who accused him of being a deserter and a traitor. From 1922 to 1932 Nicolai lived in Argentina, and from 1932 until his death in 1964, in Chile. In this later country Nicolai was professor in the University of Chile and interacted with members of the Chilean intelligentsia, including the poets Vicente Huidobro, Gonzalo Rojas and Pablo Neruda. Through his friendship with Chilean psychiatrist Agustin Tellez, Nicolai influenced the development of phenomenological psychiatric school in Chile. The Chilean novelist Fernando Alegria compared him favorably with Robert J. Oppenheimer and Linus Pauling.

  14. [Carl Friedrich von Weizsäcker: nuclear disarmament and the search for freedom].

    PubMed

    Neuneck, Götz

    2014-01-01

    Carl Friedrich von Weizsäcker's comprehensive contributions to nuclear disarmament and arms control, as well as his peace policy impulses are to be understood primarily in the context of his family origin, his comprehensive thinking and the historical circumstances of the emerging nuclear age. They have a scientific, political and a strong philosophical-moral component. Beside the factual problems (nuclear energy, military strategy) he was interested in political power issues and their ambivalence and perception. His actual work is not only based on general academic knowledge, but also serve the immediate political influence on a scientific basis. Weizsäcker was not committed to nuclear disarmament or arms control per se, but about creating a lasting peace policy in the nuclear age. The paper discusses in chronological order of Weizsäcker's work within the policy field peace and disarmament. Family origin, study and work on the nuclear programme by Nazi-Germany laid the foundations for his later career. As a young physicist, he was directly involved in the political and ethical dilemma of the military and civilian use of nuclear energy. After the war, in Göttingen and Hamburg the reflections of the Nazi phase and the discussion of ways out of the dangers of the Cold War followed. The Max-Planck Institute in Starnberg dealt with the science-based treatment of global world problems, including the dangers of nuclear proliferation. Finally, Weizsäcker initiated a Peace Council in 1985. He urged both the perception of the moral responsibility of scientists as well as an ethics of the scientific-technological age. According to him, a general and profound change in the consciousness of humankind is needed to solve the existing power problems and the problem of war. PMID:24974615

  15. A combined tvd-lax-friedrichs scheme and its application in multi-streamer structure solar wind modeling

    NASA Astrophysics Data System (ADS)

    Feng, X.; Wei, F.; Wu, S.; Fan, Q.

    By employing a modified Lax-Friedrichs scheme for the fluid part and MacCormack II scheme for the magnetic induction part in MHD equations and taking consideration of large-scale structure of solar-terrestrial simulation, a combined TVD type numerical model is introduced for solar wind m deling. To show theo validation of this new model, its ability of modeling solar wind background with multi-streamer structures is investigated here, showing strong robustness and stability without any artificial diffusion added. Numerical results are in agreement with former widely accepted ones by giving fine structures.

  16. Convergence of Lax-Friedrichs and Godunov schemes for a nonstrictly hyperbolic system of conservation laws arising in oil recovery

    NASA Astrophysics Data System (ADS)

    Djoufedie, George Noel; Felaco, Elisabetta; Rubino, Bruno; Sampalmieri, Rosella

    2016-03-01

    This paper is devoted to the compactness framework and the convergence theorem for the Lax-Friedrichs and Godunov schemes applied to a {2 × 2} system of non-strictly hyperbolic nonlinear conservation laws that arises from mathematical models for oil recovery. The presence of a degeneracy in the hyperbolicity of the system requires a careful analysis of the entropy functions, whose regularity is necessary to obtain the result. For this purpose, it is necessary to combine the classical techniques referring to a singular Euler-Poisson-Darboux equation with the compensated compactness method.

  17. "A talented young man" - The short life of Friedrich Wilhelm Tönnies, 1796-1817; (German Title: "Ein talentvoller junger Mann" - Das kurze Leben des Friedrich Wilhelm Tönnies, 1796-1817)

    NASA Astrophysics Data System (ADS)

    Schwemin, Friedhelm

    Friedrich Wilhelm Tönnies' name is hardly found in the major histories of astronomy. This is not surprising since he died before the age of twenty-one. Nevertheless, and perhaps because he knew at heart that not much time was granted to him, he left an astonishingly prolific oeuvre which indicates his rich talents. His contemporaries also testify that this son af a wealthy textile merchant had a great talent. But it is idle to speculate whether he would have become a second Bessel, or just an inconspicuous high school teacher in some remote Prussian province. He experienced a decisive career advancement by the Berlin astronomer J.E. Bode, obtained his Ph.D. already at the age of nineteen, published, among other things, about the large solar eclipse of November 19, 1816, and corresponded with several professional astronomers, before he succumbed to a pulmonary disease.

  18. [A failed experiment - Carl Friedrich von Weizsäcker, Jürgen Habermas and the Max-Planck Society].

    PubMed

    Leendertz, Ariane

    2014-01-01

    From 1970 to 1980 Carl Friedrich von Weizsäcker headed the Max-Planck-lnstitut zur Erforschung der Lebensbedingungen der wissenschaftlich-technischen Welt (MPI for the study of the living conditions of the world of science and technology) in Starnberg, jointly with Jürgen Habermas since 1971. From the start, the Max Planck Society regarded the new institute as an experiment that might perhaps be aborted a few years later. This is exactly what happened. With the retirement of Weizsäcker, his section was closed and the whole institute was renamed. In 1981. Habermas resigned, and then the institute was closed. This paper focusses on some of the problem constellations within the institute that partly explain its development and eventual closure: its birth out of the idea of scientific policy advice, the debates within the Max Planck Society and the complex relationship between Weizsäcker and Jürgen Habermas.

  19. [Encounters and re-encounters - philosophy and religion of the physicist Carl Friedrich von Weizsäcker].

    PubMed

    Meyer-Abich, Michael

    2014-01-01

    (1) Quantum theory deals not just with reality but with the physical (scientific) reality of its objects. Carl Friedrich von Weizsäcker understood this to imply that scientific knowledge of objects converges with philosophical knowledge of their objectivity but did not succeed in rounding off physics. (2) We are actors as well as spectators not only in scientific knowledge but in political processes as well, particularly by means of science. It is, therefore, not justified to deny political responsibility even in 'basic research'. Carl Friedrich von Weizsacker identified classical physics as the venture of knowledge without love but believed that this boundary could be transcended. The apparent neutrality of science must not be tolerated by the churches, however. (3) In religion Weizsäcker felt most at home in Buddhist spirituality, this being akin to Christian spirituality which has been more or less lost by the Christian churches. Yet he tried to support his church and to participate in its actions. (4) Lack of love corresponds to an excess of power in the religious critique of science. In both respects Weizsäcker presented the mirror to industrial society but people in general did not recognize their image. The Max-Planck-Society, however, shut up Weizsäcker's "Institute for the study of the conditions of life in the modern world" (Starnberg 1970-1980) as soon as possible. (5) Weizsäcker always refrained from exerting any power except that of reason or truth. According to Lao Tse this is the power least perceived as such. In politics he generally followed the mainstream after once having been tempted to action in 1941/42. His influence on German society was based on his charismatic spirituality.

  20. Animal Magnetism, Psychiatry and Subjective Experience in Nineteenth-Century Germany: Friedrich Krauß and his Nothschrei

    PubMed Central

    Brückner, Burkhart

    2016-01-01

    Friedrich Krauß (1791–1868) is the author of Nothschrei eines Magnetisch-Vergifteten [Cry of Distress by a Victim of Magnetic Poisoning] (1852), which has been considered one of the most comprehensive self-narratives of madness published in the German language. In this 1018-page work Krauß documents his acute fears of ‘mesmerist’ influence and persecution, his detainment in an Antwerp asylum and his encounter with various illustrious physicians across Europe. Though in many ways comparable to other prominent nineteenth-century first-person accounts (eg. John Thomas Perceval’s 1838 Narrative of the Treatment Experienced by a Gentleman or Daniel Paul Schreber’s 1903 Memoirs of my Nervous Illness), Krauß’s story has received comparatively little scholarly attention. This is especially the case in the English-speaking world. In this article I reconstruct Krauß’s biography by emphasising his relationship with physicians and his under-explored stay at the asylum. I then investigate the ways in which Krauß appropriated nascent theories about ‘animal magnetism’ to cope with his disturbing experiences. Finally, I address Krauß’s recently discovered calligraphic oeuvre, which bears traces of his typical fears all the while showcasing his artistic skills. By moving away from the predominantly clinical perspective that has characterised earlier studies, this article reveals how Friedrich Krauß sought to make sense of his experience by selectively appropriating both orthodox and non-orthodox forms of medical knowledge. In so doing, it highlights the mutual interaction of discourses ‘from above’ and ‘from below’ as well as the influence of broader cultural forces on conceptions of self and illness during that seminal period. PMID:26651186

  1. Animal Magnetism, Psychiatry and Subjective Experience in Nineteenth-Century Germany: Friedrich Krauß and his Nothschrei.

    PubMed

    Brückner, Burkhart

    2016-01-01

    Friedrich Krauß (1791-1868) is the author of Nothschrei eines Magnetisch-Vergifteten [Cry of Distress by a Victim of Magnetic Poisoning] (1852), which has been considered one of the most comprehensive self-narratives of madness published in the German language. In this 1018-page work Krauß documents his acute fears of 'mesmerist' influence and persecution, his detainment in an Antwerp asylum and his encounter with various illustrious physicians across Europe. Though in many ways comparable to other prominent nineteenth-century first-person accounts (eg. John Thomas Perceval's 1838 Narrative of the Treatment Experienced by a Gentleman or Daniel Paul Schreber's 1903 Memoirs of my Nervous Illness), Krauß's story has received comparatively little scholarly attention. This is especially the case in the English-speaking world. In this article I reconstruct Krauß's biography by emphasising his relationship with physicians and his under-explored stay at the asylum. I then investigate the ways in which Krauß appropriated nascent theories about 'animal magnetism' to cope with his disturbing experiences. Finally, I address Krauß's recently discovered calligraphic oeuvre, which bears traces of his typical fears all the while showcasing his artistic skills. By moving away from the predominantly clinical perspective that has characterised earlier studies, this article reveals how Friedrich Krauß sought to make sense of his experience by selectively appropriating both orthodox and non-orthodox forms of medical knowledge. In so doing, it highlights the mutual interaction of discourses 'from above' and 'from below' as well as the influence of broader cultural forces on conceptions of self and illness during that seminal period.

  2. [Encounters and re-encounters - philosophy and religion of the physicist Carl Friedrich von Weizsäcker].

    PubMed

    Meyer-Abich, Michael

    2014-01-01

    (1) Quantum theory deals not just with reality but with the physical (scientific) reality of its objects. Carl Friedrich von Weizsäcker understood this to imply that scientific knowledge of objects converges with philosophical knowledge of their objectivity but did not succeed in rounding off physics. (2) We are actors as well as spectators not only in scientific knowledge but in political processes as well, particularly by means of science. It is, therefore, not justified to deny political responsibility even in 'basic research'. Carl Friedrich von Weizsacker identified classical physics as the venture of knowledge without love but believed that this boundary could be transcended. The apparent neutrality of science must not be tolerated by the churches, however. (3) In religion Weizsäcker felt most at home in Buddhist spirituality, this being akin to Christian spirituality which has been more or less lost by the Christian churches. Yet he tried to support his church and to participate in its actions. (4) Lack of love corresponds to an excess of power in the religious critique of science. In both respects Weizsäcker presented the mirror to industrial society but people in general did not recognize their image. The Max-Planck-Society, however, shut up Weizsäcker's "Institute for the study of the conditions of life in the modern world" (Starnberg 1970-1980) as soon as possible. (5) Weizsäcker always refrained from exerting any power except that of reason or truth. According to Lao Tse this is the power least perceived as such. In politics he generally followed the mainstream after once having been tempted to action in 1941/42. His influence on German society was based on his charismatic spirituality. PMID:24974621

  3. ["... and of course my views have become more independent"--Friedrich Ratzel's letters to Ernst Haeckel, his mentor and academic colleague].

    PubMed

    Zigman, Peter M

    2009-01-01

    This article for the first time provides an edition and commentary of the letters of Friedrich Ratzel to his older colleague, teacher and mentor, Ernst Haeckel, which are kept in the archive of the Ernst-Haeckel-House (memorial museum) in Jena. Altogether fifteen letters and one postcard are presented. Haeckel's letters to Ratzel are considered to be lost. The edition is prefaced with a detailed description of Ratzel's life, career and work, as a part of the edition. PMID:20509448

  4. ["... and of course my views have become more independent"--Friedrich Ratzel's letters to Ernst Haeckel, his mentor and academic colleague].

    PubMed

    Zigman, Peter M

    2009-01-01

    This article for the first time provides an edition and commentary of the letters of Friedrich Ratzel to his older colleague, teacher and mentor, Ernst Haeckel, which are kept in the archive of the Ernst-Haeckel-House (memorial museum) in Jena. Altogether fifteen letters and one postcard are presented. Haeckel's letters to Ratzel are considered to be lost. The edition is prefaced with a detailed description of Ratzel's life, career and work, as a part of the edition.

  5. [Friedrich Berthold Reinke (1862-1919) : Rostock anatomist and describer of Reinke's crystals in the testis and Reinke's space in the larynx].

    PubMed

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

    2014-08-01

    The 95th anniversary of the anatomist Friedrich Berthold Reinke's death is 19 May 2014. This an excellent moment to remember his anatomical research. Two structures which he discovered and first described continue to be associated with his name: Reinke crystals of testicular Leydig cells and Reinke's space in the larynx. Reinke's crystals are crystalline protein aggregates within interstitial Leydig cells which are probably associated with testosterone production. They are pathognomonic for Leydig cell tumours.

  6. Human and animal health on three continents--a biography of the early life of Karl Friedrich Meyer (1884-1974).

    PubMed

    Pospischil, Andreas

    2015-08-01

    Karl Friedrich Meyer (KF) was born and educated as a veterinarian in Europe; he researched infectious diseases in Europe, South Africa and the United States. He is one of the true forefathers of the 'one health-one medicine' concept. The broad scope of his research covered botulism, leptospirosis, brucellosis, plague, ornithosis, Western equine encephalitis, mussel poisoning and clostridia. This manuscript adds some more details of his early biography.

  7. KARL FRIEDRICH ZOELLNER and the historical dimension of astronomical photometry A collection of papers on the History of Photometry

    NASA Astrophysics Data System (ADS)

    Sterken, C.; Staubermann, K. B.

    This book results from presentations and discussions of a group of astronomers and historians during a one-day workshop held at Archenhold Observatory, Berlin-Treptow, on April 4, 1997. This meeting was the first forum in a series dedicated to historical aspects of observational astrophysics in the nineteenth and early twentieth century. The basic principle of these meetings is to reflect during one or more days on the work and personality of a single individual or of a group of persons, at the same time avoiding the really dominant figures that typify the age. By focusing on key people who epitomize a way of thinking and working that has formed many of the ideas by which we do astrophysical research today, we also attempt to evoke the scientific spirit of the era under consideration. In 1858, the German physicist Karl Friedrich Zoellner introduced a new type of astronomical photometer which became a bestseller in the second half of the nineteenth century and which led him to the first German professorship in astrophysics. His type of photometer allowed most accurate photometric measurements and was used at several observatories for almost half a century. This book outlines four major themes. The first part describes the observing instruments that were used by Zoellner and his contemporaries: photometers and spectrographs that complemented his original design, but also competed with his most versatile prototype photometer. The description also includes an account of technical aspects associated with the replication of such a photometer today. The second part analyses the astrophysical data that were obtained with Zoellner's tools, and extracts information hidden in the published data --- scientific information as well as diverse aspects related to the observer himself. These nineteenth-century data are now published for the first time on a modern magnitude scale and are directly accessible in tabular form, and are thus fully applicable to archeophotometric studies

  8. [A utopian episode - Carl Friedrich von Weizsäcker in the networks of the Max-Planck Society].

    PubMed

    Kant, Horst; Renn, Jürgen

    2014-01-01

    Carl Friedrich von Weizsäcker was a key figure in the history of the Max Planck Society (MPS). This essay contextualises his work with the development of the MPS, highlighting the institutional and personal networks upon which it was based. Some of the stations addressed in the following are his role in the German Uranium Project, in preparing the Mainau Declaration, the Göttingen Manifesto, and the Memorandum of Tübingen as well as his involvement in the foundation of the Max Planck Institute (MPI) for Human Development and his own MPI for the Research of Living Conditions in the Modern World located in Starnberg. The relationship between Weizsäcker and Hellmut Becker, long-time friend and founding director of the MPI for Human Development, will be of particular interest. Another issue broached here is the connection between natural science and the humanities in Weizsäcker's work, and subsequently the relation between these two science cultures in the MPS. Finally, we look at the challenges Weizsäcker's work could present to the MPS today.

  9. [Living with responsibility: Max Born and Carl Friedrich von Weizsäcker as philosophers with distance].

    PubMed

    Schirrmacher, Arne

    2014-01-01

    Both Carl Friedrich von Weizsäcker und Max Born belong to the most active scientists, which have raised their voice for peace in the 1950s. While Born, senior to Weizsäcker by one generation, engaged in peace movements at an early stage, which was also due to his emigration, and was a driving force for the Einstein-Russell memorandum, Weizsäcker entered the stage essentially with the Göttingen declaration but quickly dominated the discourse. The comparison of their different engagements for peace sheds new light on Weizsäcker. Unlike the German emigrant with a British passport, who was mainly influenced by EInstein and Russell as well as some socialist thoughts he had encountered at an early age, the son of a noble diplomat and the physicist, who was saved from military duties because of his work in the German wartime nuclear project, had quite a different perspective on the postwar atomic threat. The relation of Born and Weizsäcker remained marked by a certain distance even when both took up very similar roles of 'public scientists' active for peace, be it as delegates at Pugwash conferences, on the air, or as speakers in the Frankfurt Paulskirche.

  10. 'Tipping the Balance': Karl Friedrich Meyer, Latent Infections, and the Birth of Modern Ideas of Disease Ecology.

    PubMed

    Honigsbaum, Mark

    2016-04-01

    The Swiss-born medical researcher Karl Friedrich Meyer (1884-1974) is best known as a 'microbe hunter' who pioneered investigations into diseases at the intersection of animal and human health in California in the 1920s and 1930s. In particular, historians have singled out Meyer's 1931 Ludwig Hektoen Lecture in which he described the animal kingdom as a 'reservoir of disease' as a forerunner of 'one medicine' approaches to emerging zoonoses. In so doing, however, historians risk overlooking Meyer's other intellectual contributions. Developed in a series of papers from the mid-1930s onwards, these were ordered around the concept of latent infections and sought to link microbial behavior to broader bio-ecological, environmental, and social factors that impact hostpathogen interactions. In this respect Meyer-like the comparative pathologist Theobald Smith and the immunologist Frank Macfarlane Burnet-can be seen as a pioneer of modern ideas of disease ecology. However, while Burnet's and Smith's contributions to this scientific field have been widely acknowledged, Meyer's have been largely ignored. Drawing on Meyer's published writings and private correspondence, this paper aims to correct that lacuna while contributing to a reorientation of the historiography of bacteriological epidemiology. In particular I trace Meyer's intellectual exchanges with Smith, Burnet and the animal ecologist Charles Elton, over brucellosis, psittacosis and plague-exchanges that not only showed how environmental and ecological conditions could 'tip the balance' in favor of parasites but which transformed Meyer thinking about resistance to infection and disease.

  11. [Living with responsibility: Max Born and Carl Friedrich von Weizsäcker as philosophers with distance].

    PubMed

    Schirrmacher, Arne

    2014-01-01

    Both Carl Friedrich von Weizsäcker und Max Born belong to the most active scientists, which have raised their voice for peace in the 1950s. While Born, senior to Weizsäcker by one generation, engaged in peace movements at an early stage, which was also due to his emigration, and was a driving force for the Einstein-Russell memorandum, Weizsäcker entered the stage essentially with the Göttingen declaration but quickly dominated the discourse. The comparison of their different engagements for peace sheds new light on Weizsäcker. Unlike the German emigrant with a British passport, who was mainly influenced by EInstein and Russell as well as some socialist thoughts he had encountered at an early age, the son of a noble diplomat and the physicist, who was saved from military duties because of his work in the German wartime nuclear project, had quite a different perspective on the postwar atomic threat. The relation of Born and Weizsäcker remained marked by a certain distance even when both took up very similar roles of 'public scientists' active for peace, be it as delegates at Pugwash conferences, on the air, or as speakers in the Frankfurt Paulskirche. PMID:24974612

  12. [A utopian episode - Carl Friedrich von Weizsäcker in the networks of the Max-Planck Society].

    PubMed

    Kant, Horst; Renn, Jürgen

    2014-01-01

    Carl Friedrich von Weizsäcker was a key figure in the history of the Max Planck Society (MPS). This essay contextualises his work with the development of the MPS, highlighting the institutional and personal networks upon which it was based. Some of the stations addressed in the following are his role in the German Uranium Project, in preparing the Mainau Declaration, the Göttingen Manifesto, and the Memorandum of Tübingen as well as his involvement in the foundation of the Max Planck Institute (MPI) for Human Development and his own MPI for the Research of Living Conditions in the Modern World located in Starnberg. The relationship between Weizsäcker and Hellmut Becker, long-time friend and founding director of the MPI for Human Development, will be of particular interest. Another issue broached here is the connection between natural science and the humanities in Weizsäcker's work, and subsequently the relation between these two science cultures in the MPS. Finally, we look at the challenges Weizsäcker's work could present to the MPS today. PMID:24974604

  13. Triple differential cross sections for the ionization of water by electron impact

    NASA Astrophysics Data System (ADS)

    Tóth, Istvan; Nagy, Ladislau; Campeanu, Radu I.

    2014-12-01

    Calculated triple differential cross sections are presented for the ionization of the 3a1 orbital of water by electron impact. The cross sections are determined for symmetric coplanar and non-coplanar geometrical arrangements. The obtained results show reasonable agreement with experimental data for both geometries. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Stefan Matejcik, John Tanis and Kurt H. Becker.

  14. [The German physician and pacifist Georg Friedrich Nicolai (1874-1964) as a pupil of the Russian physiologist Ivan Petrovic Pavlov (1849-1936)].

    PubMed

    Kästner, Ingrid

    2005-01-01

    In 1906, Dr. med. Georg Friedrich Nicolai, a young specialist in the field of electrocardiography from the university of Berlin, spent some months in the laboratory of Pavlov, where he was one of the first German visitors. Two letters written by Nicolai to Pavlov are a mirror of Nicolai's admiration for the brilliant Russian Nobel prize winner, but also of Nicolai's remarkable insight into the perspectives of Pavlov's physiological method for "objective" psychological investigations. Nicolai regarded himself a pupil of Pavlov until his death in South America, where he was forced to emigrate after World War I due to his pacifist activities.

  15. Friedrich Nietzsche (1844-1900): a classical case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome?

    PubMed

    Koszka, Christiane

    2009-08-01

    Friedrich Nietzsche was one of the most influential and profound German philosophers. After prolonged illness, he died at the age of 55 in Weimar, Germany. The interest in his medical biography has always been strong while the cause of his illness and death has remained a mystery, intriguing philosophers as well as physicians. The diagnosis of syphilis proposed in the 19th century has been controversial until today and many other diagnoses have been discussed. This paper suggests that Nietzsche suffered from mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes syndrome.

  16. [The German physician and pacifist Georg Friedrich Nicolai (1874-1964) as a pupil of the Russian physiologist Ivan Petrovic Pavlov (1849-1936)].

    PubMed

    Kästner, Ingrid

    2005-01-01

    In 1906, Dr. med. Georg Friedrich Nicolai, a young specialist in the field of electrocardiography from the university of Berlin, spent some months in the laboratory of Pavlov, where he was one of the first German visitors. Two letters written by Nicolai to Pavlov are a mirror of Nicolai's admiration for the brilliant Russian Nobel prize winner, but also of Nicolai's remarkable insight into the perspectives of Pavlov's physiological method for "objective" psychological investigations. Nicolai regarded himself a pupil of Pavlov until his death in South America, where he was forced to emigrate after World War I due to his pacifist activities. PMID:17153304

  17. ["The hard core". Science between politics and philosophy by Carl Friedrich von Weizsäcker and in the finalization theory].

    PubMed

    Krohn, Wolfgang

    2014-01-01

    In the Starnberg Max-Planck Institute one of the working groups was concerned with science as the formative condition--or "hard core"--of societal modernity, and with science as potential resource for solving social problems and addressing future goals. More precisely, the group intended to differentiate between phases in which scientific disciplines predominantly care for their own paradigmatic completion and those allowing their theoretical potential resonate with external needs. The conceptual model was coined "finalization in science". It soon provoked a heated controversy on the dangers of social control of science. The paper analyses Carl Friedrich von Weizsäcker's views on the relation between philosophy and policy of science including his interpretation of Thomas Kuhn and reconstructs the impact of his ideas on the finalization model. It finally reflects on the relationship between science development and change of consciousness in the context of scientific responsibility for (the use of) research outcomes.

  18. [The "utopian" national socialism - a mutual dispute in the philosophy of Martin Heidegger and Carl Friedrich von Weizsäcker?].

    PubMed

    Schäfer, Wolf

    2014-01-01

    In a letter to his wife from October 14, 1943, Werner Heisenberg describes a fierce clash with Carl Friedrich von Weizsäcker. The sudden conflict raises numerous questions, two of which are tackled here. First: How is now the friendly relationship between Heisenberg and Weizsäcker in the postwar years to be understood? The answer is: as a strategic performance. Second: How are the radical opinions to be explained that Weizsäcker expressed at the time? A thorough reconstruction of the lifelong connection that Weizsäcker maintained with Martin Heidegger and Heidegger's philosophy gives the answer: the young Weizsäcker was fired up by the "utopian" National Socialism with which Heidegger trumped the real existing. PMID:24974620

  19. [The "utopian" national socialism - a mutual dispute in the philosophy of Martin Heidegger and Carl Friedrich von Weizsäcker?].

    PubMed

    Schäfer, Wolf

    2014-01-01

    In a letter to his wife from October 14, 1943, Werner Heisenberg describes a fierce clash with Carl Friedrich von Weizsäcker. The sudden conflict raises numerous questions, two of which are tackled here. First: How is now the friendly relationship between Heisenberg and Weizsäcker in the postwar years to be understood? The answer is: as a strategic performance. Second: How are the radical opinions to be explained that Weizsäcker expressed at the time? A thorough reconstruction of the lifelong connection that Weizsäcker maintained with Martin Heidegger and Heidegger's philosophy gives the answer: the young Weizsäcker was fired up by the "utopian" National Socialism with which Heidegger trumped the real existing.

  20. [Medicine and natural sciences in the Dessau cultural district of the 18th century. On the 250th anniversary of the birth of Leopold Friedrich Franz (1740-1817) of Anhalt-Dessau].

    PubMed

    Kaiser, W

    1990-08-01

    The 250th anniversary of the birthday of Prince Leopold Friedrich Franz of Anhalt-Dessau gives occasion to the appreciation of the progressive achievements of this representative of an enlightened absolutism, taking into particular consideration medicine and natural sciences. Under his reign a public health was established which was exemplarily organized by Dessau community physicians, the benefit of which the whole population of the country enjoyed.

  1. [Medicine and natural sciences in the Dessau cultural district of the 18th century. On the 250th anniversary of the birth of Leopold Friedrich Franz (1740-1817) of Anhalt-Dessau].

    PubMed

    Kaiser, W

    1990-08-01

    The 250th anniversary of the birthday of Prince Leopold Friedrich Franz of Anhalt-Dessau gives occasion to the appreciation of the progressive achievements of this representative of an enlightened absolutism, taking into particular consideration medicine and natural sciences. Under his reign a public health was established which was exemplarily organized by Dessau community physicians, the benefit of which the whole population of the country enjoyed. PMID:2247994

  2. [Living without atomic power? Carl Friedrich von Weizsäcker as expert in the nuclear energy debate of the 1970's].

    PubMed

    Seefried, Elke

    2014-01-01

    Carl Friedrich von Weizsäcker crossed the boundaries separating science, politics and the public sphere. In this he was led by the conviction that scientists in the modern 'technical age' are responsible for consequences resulting from their applied knowledge. Weizsäcker tried to introduce his knowledge into the policy process by advising politicians or by using the public sphere, thus applying pressure on politics. This was not only true for the 'Göttinger Erklärung' in 1957 but also for his engagement in the nuclear energy debate of the 1970s. Influenced by the 'Limits to Growth' discourse, Weizsäcker more and more gravitated towards an ecological world view and increasingly questioned material growth as well as a techno-scientific based understanding of progress. Weizsäcker thought about risks of the technical age in general and of the use of nuclear energy in particular. In the light of a growing fragmentation of scientific authority, Weizsäcker revealed uncertainty as he became fully aware that expertise cannot be based on scientific reason and cannot code the problems in terms of truth, but is inextricably linked with value spheres and contingencies. Nevertheless, his expertise was utilized as he encouraged parts of the Social Democratic Party (SPD) around Erhard Eppler to think about alternatives in energy policy. PMID:24974614

  3. ["World domestic policy" as a way to eternal peace? Carl Friedrich von Weizsäcker's realistic idealism as theory of a sustainable policy].

    PubMed

    Bartosch, Ulrich

    2014-01-01

    The intention of this article is to show the suitability of "Weltinnenpolitik" (world domestic policy) as an analytic and programmatic view on contemporary policy. A full reconstruction or comparison of Carl Friedrich von Weizsäcker's concept is not at the focus. As mentioned in other contributions to this volume, Weizsäcker did not refer to the disciplinary discourses in detail. His approach is particularly 'unique' since he set about in 1963 to study the conditions of peace in a very general way. By doing so, he was able to circumscribe the conditions of peace realistically: those valid for us today and apparently also in the future. Weizsäcker probably did underestimate the complexity of the transformation to sustainable politics for preventing climate change. Vice versa one should hope that we today do not discount the prevention of atomic war as a sine qua non for sustainable climate-saving policy. Both could mark the quintessential conditions for peace. PMID:24974610

  4. [Living without atomic power? Carl Friedrich von Weizsäcker as expert in the nuclear energy debate of the 1970's].

    PubMed

    Seefried, Elke

    2014-01-01

    Carl Friedrich von Weizsäcker crossed the boundaries separating science, politics and the public sphere. In this he was led by the conviction that scientists in the modern 'technical age' are responsible for consequences resulting from their applied knowledge. Weizsäcker tried to introduce his knowledge into the policy process by advising politicians or by using the public sphere, thus applying pressure on politics. This was not only true for the 'Göttinger Erklärung' in 1957 but also for his engagement in the nuclear energy debate of the 1970s. Influenced by the 'Limits to Growth' discourse, Weizsäcker more and more gravitated towards an ecological world view and increasingly questioned material growth as well as a techno-scientific based understanding of progress. Weizsäcker thought about risks of the technical age in general and of the use of nuclear energy in particular. In the light of a growing fragmentation of scientific authority, Weizsäcker revealed uncertainty as he became fully aware that expertise cannot be based on scientific reason and cannot code the problems in terms of truth, but is inextricably linked with value spheres and contingencies. Nevertheless, his expertise was utilized as he encouraged parts of the Social Democratic Party (SPD) around Erhard Eppler to think about alternatives in energy policy.

  5. [Friedrich Panse: well established in all systems. Psychiatrist in the Weimar Republic, in the Third Reich, and in the Federal Republic of Germany].

    PubMed

    Forsbach, R

    2012-03-01

    The psychiatrist Friedrich Panse (1899-1973) was a T4 assessor during the Nazi era who sent mentally disabled and mentally ill people to their deaths. In the German Armed Forces he used higher galvanic currents to cure "war neurotics" and expose "malingerers." As a National Socialist he was a committed teacher of racial hygiene. Nonetheless, after the end of the Nazi regime many supporters quickly surfaced who were prepared to exonerate Panse. Panse himself was not among those who indignantly repudiated the accusation of any contact with the Nazi Party. He did not deny that he had openly embraced the Nazi measures for preserving the genetic integrity of the populace, but he did let it be known that he had suffered incredibly under the heavy burden. The State Government of North Rhine-Westphalia refused to allow Panse to continue in his capacity as an extraordinary professor. Panse successfully contested this decision at the State Administrative Court in Düsseldorf. He became the Director of the Institution in Düsseldorf-Grafenberg, the Psychiatric Clinic in Düsseldorf, a member of the German Council of Medical Advisors for questions regarding care for war victims of the German Federal Ministry of Labor, and President of the German Society for Psychiatry and Neurology. PMID:22399062

  6. [Friedrich Panse: well established in all systems. Psychiatrist in the Weimar Republic, in the Third Reich, and in the Federal Republic of Germany].

    PubMed

    Forsbach, R

    2012-03-01

    The psychiatrist Friedrich Panse (1899-1973) was a T4 assessor during the Nazi era who sent mentally disabled and mentally ill people to their deaths. In the German Armed Forces he used higher galvanic currents to cure "war neurotics" and expose "malingerers." As a National Socialist he was a committed teacher of racial hygiene. Nonetheless, after the end of the Nazi regime many supporters quickly surfaced who were prepared to exonerate Panse. Panse himself was not among those who indignantly repudiated the accusation of any contact with the Nazi Party. He did not deny that he had openly embraced the Nazi measures for preserving the genetic integrity of the populace, but he did let it be known that he had suffered incredibly under the heavy burden. The State Government of North Rhine-Westphalia refused to allow Panse to continue in his capacity as an extraordinary professor. Panse successfully contested this decision at the State Administrative Court in Düsseldorf. He became the Director of the Institution in Düsseldorf-Grafenberg, the Psychiatric Clinic in Düsseldorf, a member of the German Council of Medical Advisors for questions regarding care for war victims of the German Federal Ministry of Labor, and President of the German Society for Psychiatry and Neurology.

  7. ["World domestic policy" as a way to eternal peace? Carl Friedrich von Weizsäcker's realistic idealism as theory of a sustainable policy].

    PubMed

    Bartosch, Ulrich

    2014-01-01

    The intention of this article is to show the suitability of "Weltinnenpolitik" (world domestic policy) as an analytic and programmatic view on contemporary policy. A full reconstruction or comparison of Carl Friedrich von Weizsäcker's concept is not at the focus. As mentioned in other contributions to this volume, Weizsäcker did not refer to the disciplinary discourses in detail. His approach is particularly 'unique' since he set about in 1963 to study the conditions of peace in a very general way. By doing so, he was able to circumscribe the conditions of peace realistically: those valid for us today and apparently also in the future. Weizsäcker probably did underestimate the complexity of the transformation to sustainable politics for preventing climate change. Vice versa one should hope that we today do not discount the prevention of atomic war as a sine qua non for sustainable climate-saving policy. Both could mark the quintessential conditions for peace.

  8. Electron-impact-induced tryptophan molecule fragmentation

    NASA Astrophysics Data System (ADS)

    Tamuliene, Jelena; Romanova, Liudmila G.; Vukstich, Vasyl S.; Papp, Alexander V.; Snegursky, Alexander V.

    2015-01-01

    The fragmentation of a gas-phase tryptophan molecule by a low-energy (<70 eV) electron impact was studied both experimentally and theoretically. Various positively charged fragments were observed and analyzed. A special attention was paid to the energy characteristics of the ionic fragment yield. The geometrical parameters of the initial molecule rearrangement were also analyzed. The fragmentation observed was due to either a simple bond cleavage or more complex reactions involving molecular rearrangements. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Stefan Matejcik, John Tanis and Kurt H. Becker.

  9. Two-electron exchange interaction between polar molecules and atomic ions — Asymptotic approach

    NASA Astrophysics Data System (ADS)

    Karbovanets, Oleksandr M.; Karbovanets, Myroslav I.; Khoma, Mykhaylo V.; Lazur, Volodymyr Yu.

    2015-05-01

    We have described the asymptotic approach for calculation of the two-electron exchange interaction between atomic ion and polar molecule responsible for direct double electron transfer processes. The closed analytic expression for matrix element of exchange interaction has been obtained in the framework of the semiclassical version of the asymptotic theory and point-dipole approximation for description of the polar molecule. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Štefan Matejčik, John Tanis and Kurt H. Becker.

  10. [Friedrich Wilhelm I and porphyria].

    PubMed

    Pierach, C A; Jennewein, E

    1999-01-01

    Historical evidence has been collected attempting to diagnose members of royal houses, perhaps most publicized by Macalpine and Hunter (1969) for George III and his assumed porphyria, claiming that his insanity was a classic case of thereof. This rare metabolic disease presents with a variety of signs and symptoms: skin disease, abdominal pain, tachycardia, and neuro-psychiatric findings. The porphyrias are hereditary and since George III and Frederick William I share ancestors it seemed reasonable to investigate if the latter may also have suffered from porphyria. The pathography of both kings is meticulous, showing for both that abdominal pain, erratic behavior, restlessness, and discolored urine were frequently observed and complete recovery interictally was common. Intercurrent illnesses, fasting, alcohol and even tobacco smoking have been shown to be inducers of attacks and these risk factors are well documented in royal history.--The diagnosis of porphyria was not recognized then and other names were used, such as Cachexia hypochondriaca, Asthma spasmodico flatulentum, dolores arthritici.--We propose that Frederick William I suffered from an inducible porphyria.

  11. [Friedrich Nietzsche's last lucid year].

    PubMed

    Figueroa, Gustavo

    2007-05-01

    As an outstanding philosopher Nietzsche poses the question whether his creativeness persisted in spite of his deteriorating disease or appeared, among other features, as a consequence of his illness. A thorough psychopathological understanding of his last lucid year is attempted. He had an exaggerated self-esteem and grandiose sense of confidence and achievements. But his lack of insight did not lead him to engage in activities that could harm himself or his loved ones. Between January 1888 and until his ultimate deterioration in January 1889, Nietzsche was exceedingly productive. During this period, polar changes along with moderately overlapping periods appeared.

  12. [Carl Friedrich von Weizsäcker - supporter of the concept of the East German movement in favor of self-organization during the political turning point 1989/90].

    PubMed

    Gebhardt, Gerd

    2014-01-01

    The luminosity of Carl Friedrich von Weizsäcker's holistic thinking in the former German Democratic Republic (DDR) is reviewed. Broad-minded academics sought, in accordance with the modern paradigm of self-organization, beyond the ideological template for ways out of the dead end of incrustations of society and innovation blockages under the constraints of a dictatorship. Right after the fall of the wall, Weizsäcker willingly backed a "community of free researchers for self-organization" (Freie Forschungsgemeinschaft Selbstorganisation, FFGSO). This group, conceived as a nonpartisan "think tank" of civil activism, is also discussed. At a number of its meetings Weizsäcker debated the dangers of ideologically influenced science. The effectiveness of the dual leadership at his own Starnberg Institute, for instance, was stymied by the tensions arisen out of such conflicting aims. Against the voluntaristic anticipations of the mainstream in sociology, precisely that system proved to be more viable that was meant to be overcome: faulty and purportedly futureless capitalism. Weizsäcker repudiated social prognoses made in the absence of rules for their falsification resp. verification. Weizsäcker acted as a leading figure at the FFGSO's Potsdam conference, opened on 30 Mar. 1990, on the "DDR--and afterwards?". Its intention was in order to trigger a nationwide discussion of scientific scenarios in designing German unification in the face of gross practical disparities between East and West Germany. The Trust Agency inspired by the FFGSO at the Round Table between opposition and old government was supposed to transfer the national public property "Volkseigentum" of the DDR into private property of the East German citizens, to enable them to realize a role as subject through self-organization. At the group's request, Weizsäcker mediated the readiness by the Lutheran World Federation to assume the role of ombudsman in anticipation of conflicts of interest within the

  13. [Carl Friedrich von Weizsäcker - supporter of the concept of the East German movement in favor of self-organization during the political turning point 1989/90].

    PubMed

    Gebhardt, Gerd

    2014-01-01

    The luminosity of Carl Friedrich von Weizsäcker's holistic thinking in the former German Democratic Republic (DDR) is reviewed. Broad-minded academics sought, in accordance with the modern paradigm of self-organization, beyond the ideological template for ways out of the dead end of incrustations of society and innovation blockages under the constraints of a dictatorship. Right after the fall of the wall, Weizsäcker willingly backed a "community of free researchers for self-organization" (Freie Forschungsgemeinschaft Selbstorganisation, FFGSO). This group, conceived as a nonpartisan "think tank" of civil activism, is also discussed. At a number of its meetings Weizsäcker debated the dangers of ideologically influenced science. The effectiveness of the dual leadership at his own Starnberg Institute, for instance, was stymied by the tensions arisen out of such conflicting aims. Against the voluntaristic anticipations of the mainstream in sociology, precisely that system proved to be more viable that was meant to be overcome: faulty and purportedly futureless capitalism. Weizsäcker repudiated social prognoses made in the absence of rules for their falsification resp. verification. Weizsäcker acted as a leading figure at the FFGSO's Potsdam conference, opened on 30 Mar. 1990, on the "DDR--and afterwards?". Its intention was in order to trigger a nationwide discussion of scientific scenarios in designing German unification in the face of gross practical disparities between East and West Germany. The Trust Agency inspired by the FFGSO at the Round Table between opposition and old government was supposed to transfer the national public property "Volkseigentum" of the DDR into private property of the East German citizens, to enable them to realize a role as subject through self-organization. At the group's request, Weizsäcker mediated the readiness by the Lutheran World Federation to assume the role of ombudsman in anticipation of conflicts of interest within the

  14. Argelander, Friedrich Wilhelm August (1799-1875)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Astronomer, born in Memel, East Prussia. Director of the Bonn Observatory, where he organized a survey of the position of all 324 198 stars of the northern hemisphere above the ninth magnitude, published as the star charts and catalogs of the Bonner Durchmusterung (BD). His assistant, Eduard Schönfeld (1828-91), made the extension (BDE) into the southern sky. It is staggering to think about this ...

  15. The Lee-Friedrichs Model: Continuous Limit and Decoherence

    NASA Astrophysics Data System (ADS)

    Laura, Roberto; Castagnino, Mario

    2007-09-01

    We analyze the thermodynamic limit of the Hamiltonian, states and observables, of a system containing an oscillator interacting with a thermal bath We use the results to a compare environment and self induced decoherence.

  16. An unrecognized renal physiologist: Friedrich Wöhler.

    PubMed

    Richet, G

    1995-01-01

    Wöhler, in 1828, was the first chemist to synthesize urea. In 1824, towards the end of his medical studies, he had already published an important article on the renal excretion of some 41 substances administered orally or parenterally and on the links between their renal excretion and their metabolism: salts of potassium are excreted either reduced or oxidized, urine can be acidic when the blood is alkaline, the rate of water excretion is influenced by the rate of substances excreted in the same form as they are administered. He adumbrated the general concepts on the role of the kidney in the maintenance of the composition of the body. Had he continued in this direction, Wöhler would have been recognized not only as a remarkable chemist but also as a great physiologist. PMID:8546178

  17. An unrecognized renal physiologist: Friedrich Wöhler.

    PubMed

    Richet, G

    1995-01-01

    Wöhler, in 1828, was the first chemist to synthesize urea. In 1824, towards the end of his medical studies, he had already published an important article on the renal excretion of some 41 substances administered orally or parenterally and on the links between their renal excretion and their metabolism: salts of potassium are excreted either reduced or oxidized, urine can be acidic when the blood is alkaline, the rate of water excretion is influenced by the rate of substances excreted in the same form as they are administered. He adumbrated the general concepts on the role of the kidney in the maintenance of the composition of the body. Had he continued in this direction, Wöhler would have been recognized not only as a remarkable chemist but also as a great physiologist.

  18. Martin Bartels als Lehrer von Carl Friedrich Gauß.

    NASA Astrophysics Data System (ADS)

    Dick, W. R.

    The role of the young Martin Bartels (1769 - 1836), later professor of mathematics at Kazan and Dorpat, as a teacher of C. F. Gauß is discussed on the basis of his autobiographic notes and of reminiscences by the astronomer Otto Struve, the son of Bartel's son-in-law Wilhelm Struve.

  19. Friedrich Wilhelm Bessel - the astronomer as a poet; (German Title: Friedrich Wilhelm Bessel - der Astronom als Poet)

    NASA Astrophysics Data System (ADS)

    Fürst, Dietmar

    This contribution illuminates a hitherto unknown side of the famous astronomer Bessel: his delight in occasionally writing poetry. These poems were thought to be of private use only, in particular as rhymed answers to his intimate correspondent Heinrich Christian Schumacher.

  20. Electron-induced ionization and dissociative ionization of iron pentacarbonyl molecules

    NASA Astrophysics Data System (ADS)

    Lacko, Michal; Papp, Peter; Wnorowski, Karol; Matejčík, Štefan

    2015-03-01

    Electron ionization (EI) and dissociative ionization (DI) of Iron pentacarbonyl molecule (Fe(CO)5) was studied using a crossed molecular and electron beam mass spectrometry technique. Positive ions FeO(CO)+, FeC(CO)2+ and CO+ of Fe(CO)5 were detected for the first time. We have determined the experimental appearance energies of positive ions, the thresholds for dissociative reactions, the experimental bond dissociation energies for (CO)nFe+-CO bond breaks (for n = 4,..., 0) and their average value for Fe-C bond energy 1.25 eV in Fe(CO)5+. We have performed extensive density functional theory (DFT) studies of the ground states of neutral molecule and fragments 1 A1' Fe(CO)5, 3B1 Fe(CO)4, 3A1Fe(CO)3, 3∑g Fe(CO)2, 3 ∑FeCO as well as positive ions 2A1 Fe(CO)5+, 4A1 Fe(CO)4+, 4A1 Fe(CO)3+, 4∑g Fe(CO)2+ and 4 ∑ FeCO+. The structures and energies of the states have beendetermined and the calculated bond dissociation energies (BDEs) were compared with present experiments as well as with previous works. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Stefan Matejick, John Tanis and Kurt H. Becker.

  1. Dissociative excitation study of iron pentacarbonyl molecule

    NASA Astrophysics Data System (ADS)

    Ribar, Anita; Danko, Marián; Országh, Juraj; Ferreira da Silva, Filipe; Utke, Ivo; Matejčík, Štefan

    2015-04-01

    The processes of dissociative excitation (DE) and dissociative ionisation with excitation (DIE) of iron pentacarbonyl, Fe(CO)5, have been studied using a crossed electron-molecule beam experimental apparatus (Electron Induced Fluorescence Apparatus, EIFA). Using EIFA we were able to record the emission spectrum of the molecule in the UV-VIS range, as well as the photon efficiency curves initiated by electron impact. The emission spectrum of Fe(CO)5 initiated by impact of 50 eV electrons was recorded in the spectral range between 200 nm and 470 nm. It shows a high density of emission lines and bands (mainly iron lines and carbonyl bands). Additionally, we have measured photon efficiency curves (PECs) as a function of the electron impact energy for several lines and bands. On the basis of the PECs we have discussed the reaction mechanism and the energetics of the reactions associated with the DE and DIE processes. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Štefan Matejčík, John Tanis and Kurt H. Becker.

  2. Photoionization dynamics of the C2+ ion in Rydberg states

    NASA Astrophysics Data System (ADS)

    Stancalie, Viorica

    2014-11-01

    The goal of this work is to examine in detail the ionization dynamics of Be-like C ion in Rydberg states. An initial calculation has been done to output the lifetime due to spontaneous decay for unperturbed 1s22sns (1Se) Rydberg states using the multi-configuration Dirac-Fock (MCDF) method with configuration interaction option implemented in the general-purpose relativistic atomic structure package (GRASP). Both the C2+ ground state and the C3+ target state energies have been carefully calculated. We report results from a detailed and systematic study of the behaviour of complex photoionization amplitudes, the lifetime due to spontaneous decay for unperturbed 1s22sns (1Se) Rydberg states, the `resonant' phase shift and the rapidly increasing of this shift from well below to well above the resonance position. The sum-over-state method is used to calculate the static dipole polarizability, while the frequency-dependent polarizability values of C2+ ion in these Rydberg states are obtained from two-state model calculation results. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Stefan Matejcik, John Tanis and Kurt H. Becker.

  3. Childhood, Philosophy and Play: Friedrich Schiller and the Interface between Reason, Passion and Sensation

    ERIC Educational Resources Information Center

    Weber, Barbara

    2011-01-01

    Philosophy for Children claims to foster not only critical thinking, but also creative and caring thinking. However, its theoretical foundations draw mainly on the analytic and pragmatist philosophical tradition. Consequently, and made evident by the choice of the terms "caring thinking" and "creative thinking", it seem to reduce these concepts…

  4. Does Beauty Matter in Education? Friedrich Schiller's Neo-Humanistic Approach

    ERIC Educational Resources Information Center

    Hohr, Hansjorg

    2002-01-01

    At the end of the 18th and the beginning of the 19th century, representatives of the politically oppressed middle class in a politically fragmented Germany began to look to education in search for a means of emancipation, with the pedagogical concept of "Bildung" as their central focus. The attractiveness of the concept was also a response to…

  5. My favorite aromatic compounds--a tribute to friedrich August Kekulé.

    PubMed

    Hopf, Henning

    2014-10-01

    [For a discussion of this picture, please see the Editor's postscript at the end of the paper] Note from the Editor: We are all collectors. All one needs to do is explore a flea market, an antique fair or especially a weekend street market to understand the range of human collections. Tetsuo Nozoe, whom this project celebrates, collected autographs as well as the friendship of those who signed his books! What we collect doesn't necessarily have to be tangible. We all collect memories, stories, and anecdotes. We chemists are particularly privileged: we also collect molecules and reactions. In the essay that follows, Professor Henning Hopf shares with us his collection of favorite aromatic compounds. Hopf is the perfect chemist to have undertaken this sharing, for he has been active in the field of novel aromatic compounds for over four decades. Furthermore, Hopf is a deeply philosophical scientist. I very much admire his 2008 paper with Roald Hoffmann, "Learning from Molecules in Distress" published in Angewandte Chemie, a journal from the same pubilshers as The Chemical Record. As you read the paper that follows, imagine that Professor Hopf has just welcomed you to his home and is giving you a tour of his artwork. The walls are covered with works of Boekelheide, Cram, Fittig, Hückel, Kuck, Müllen, Newman, Scott, and Willstätter among others. Oh, yes, there's a Hopf or two! Enjoy your time in this very special museum. -Jeffrey I. Seeman Guest Editor University of Richmond Richmond, Virginia 23173, USA E-mail: jseeman@richmond.edu.

  6. Going to School with Friedrich Nietzsche: The Self in Service of Noble Culture

    ERIC Educational Resources Information Center

    Yacek, Douglas W.

    2014-01-01

    To understand Nietzsche's pedagogy of self-overcoming and to determine its true import for contemporary education, it is necessary to understand Nietzsche's view of the self that is to be overcome. Nevertheless, previous interpretations of self-overcoming in the journals of the philosophy of education have lacked serious engagement with…

  7. [The symptomatic psychosis of Friedrich Nietzsche, made evident by his last attempt at an autobiography].

    PubMed

    Peters, U H

    1990-01-01

    Nietzsche's autobiography gestates neither conflicts, nor life problems, nor matter suppressed from his subconscious, nor are the speech distortions of the schizophrenic patient to be found. In all, analysis allows with certainty the conclusion that is was written by a sick person suffering from a psycho-organic disorder of the kind Bonhoeffer referred to by the general term "symptomatic psychosis".

  8. What Friedrich Nietzsche Cannot Stand about Education: Toward a Pedagogy of Self-Reformulation.

    ERIC Educational Resources Information Center

    Bingham, Charles

    2001-01-01

    Examines Nietzsche's rejection of mass education, arguing that it was based on his desire for education to be more self- reformulative than he thought possible, and concluding that education in schools is beneficial because it can foster radical forms of selfhood. This process can begin by listening to Nietzsche's philosophy while ignoring his…

  9. My favorite aromatic compounds--a tribute to friedrich August Kekulé.

    PubMed

    Hopf, Henning

    2014-10-01

    [For a discussion of this picture, please see the Editor's postscript at the end of the paper] Note from the Editor: We are all collectors. All one needs to do is explore a flea market, an antique fair or especially a weekend street market to understand the range of human collections. Tetsuo Nozoe, whom this project celebrates, collected autographs as well as the friendship of those who signed his books! What we collect doesn't necessarily have to be tangible. We all collect memories, stories, and anecdotes. We chemists are particularly privileged: we also collect molecules and reactions. In the essay that follows, Professor Henning Hopf shares with us his collection of favorite aromatic compounds. Hopf is the perfect chemist to have undertaken this sharing, for he has been active in the field of novel aromatic compounds for over four decades. Furthermore, Hopf is a deeply philosophical scientist. I very much admire his 2008 paper with Roald Hoffmann, "Learning from Molecules in Distress" published in Angewandte Chemie, a journal from the same pubilshers as The Chemical Record. As you read the paper that follows, imagine that Professor Hopf has just welcomed you to his home and is giving you a tour of his artwork. The walls are covered with works of Boekelheide, Cram, Fittig, Hückel, Kuck, Müllen, Newman, Scott, and Willstätter among others. Oh, yes, there's a Hopf or two! Enjoy your time in this very special museum. -Jeffrey I. Seeman Guest Editor University of Richmond Richmond, Virginia 23173, USA E-mail: jseeman@richmond.edu. PMID:25205433

  10. Controlling Vision - The Photometry of Karl Friedrich Zoellner PhD Thesis, with an Appendix with photographic illustrations

    NASA Astrophysics Data System (ADS)

    Staubermann, K. B.

    Using my training as an astronomer and drawing on resources such as museums, instrument collections, and archives, I have rebuilt Zoellner's astro-photometer designed by Zoellner in the late 1850s when he was working for his doctoral thesis at Basel University. The photometer was designed to compare an artificial star with a real star by means of a half-transparent screen which allowed simultaneously observation of the two together. The brightness and colour of the artificial star could be matched those of the real star by means of polarisation. After completing his instrument Zoellner observed with it at Berlin for almost two years. I have both replicated the instrument and carried out observations following Zoellner's own records. The replication of the instrument included all its optical components, the brass and wooden parts and the town gas used to produce the artificial star. This dissertation will follow the line of investigation of historical practice. The beginnings of nineteenth-century photometry will be presented, followed by a description of the Zoellner photometer, its replication and the observations carried out with the replica. I will contextualize my work based on my insights with the photometer, and then trace its career through the second half of the nineteenth century.

  11. [The "secret book" of Dr Friedrich Benjamin Osiander: anonymous births in the Göttingen Accouchierhaus, 1794-1819].

    PubMed

    Schlumbohm, Jürgen

    2014-01-01

    The problem of anonymous or confidential deliveries, a subject of current controversy, has a long history. Some maternity hospitals offered the possibility for "clandestine" births as early as the 18th and 19th century. A recently emerged source about the maternity clinic of Göttingen University allows insight into the motives that led to keeping a birth secret and the consequences of such a clandestine birth for mother, father and child. The director of the institution, a professor of obstetrics, wrote case reports on the women, who paid a handsome sum for his help and the in-patient care they received. In return, these women could be admitted under a pseudonym, and thus falsify their child's birth certificate; moreover they were not used as teaching material for medical students and midwife apprentices, whereas "regular" patients had to give their names and, in return for being treated free of charge, be available for teaching purposes. The ten cases that have been painstakingly investigated reveal that the reasons that led the women and men to opt for an anonymous birth were manifold, that they used this offer in different ways and with different consequences. All of these pregnancies were illegitimate, of course. In one case the expectant mother was married. In several cases it would be the father who was married. Most of the women who gave birth secretly seem to have given the professor their actual details and he kept quiet about them--with the exception of one case where he revealed the contents of the case report many years later in an alimony suit. Only one of the men admitted paternity openly, but many revealed their identity implicitly by registering the pregnant woman or by accompanying her to the clinic. If the birth was to be kept secret the child needed to be handed over to foster parents. By paying a lump sum that covered the usual fourteen years of parenting, one mother was able to avoid any later contact with her son. In most cases contact seems to have been limited to the payment of this boarding money. One of the couples married later and took in the twins that had been born clandestinely out of wedlock. One mother kept close contact with her son through intermediaries. All of the women who gave birth in this clandestine fashion received practical as well as financial support, often from the child's father or from a relative. Few of them came by themselves. In those days, only women who used the maternity hospital free of charge would have been as isolated in the difficult perinatal period as are women today who choose to deliver their babies anonymously.

  12. [The "secret book" of Dr Friedrich Benjamin Osiander: anonymous births in the Göttingen Accouchierhaus, 1794-1819].

    PubMed

    Schlumbohm, Jürgen

    2014-01-01

    The problem of anonymous or confidential deliveries, a subject of current controversy, has a long history. Some maternity hospitals offered the possibility for "clandestine" births as early as the 18th and 19th century. A recently emerged source about the maternity clinic of Göttingen University allows insight into the motives that led to keeping a birth secret and the consequences of such a clandestine birth for mother, father and child. The director of the institution, a professor of obstetrics, wrote case reports on the women, who paid a handsome sum for his help and the in-patient care they received. In return, these women could be admitted under a pseudonym, and thus falsify their child's birth certificate; moreover they were not used as teaching material for medical students and midwife apprentices, whereas "regular" patients had to give their names and, in return for being treated free of charge, be available for teaching purposes. The ten cases that have been painstakingly investigated reveal that the reasons that led the women and men to opt for an anonymous birth were manifold, that they used this offer in different ways and with different consequences. All of these pregnancies were illegitimate, of course. In one case the expectant mother was married. In several cases it would be the father who was married. Most of the women who gave birth secretly seem to have given the professor their actual details and he kept quiet about them--with the exception of one case where he revealed the contents of the case report many years later in an alimony suit. Only one of the men admitted paternity openly, but many revealed their identity implicitly by registering the pregnant woman or by accompanying her to the clinic. If the birth was to be kept secret the child needed to be handed over to foster parents. By paying a lump sum that covered the usual fourteen years of parenting, one mother was able to avoid any later contact with her son. In most cases contact seems to have been limited to the payment of this boarding money. One of the couples married later and took in the twins that had been born clandestinely out of wedlock. One mother kept close contact with her son through intermediaries. All of the women who gave birth in this clandestine fashion received practical as well as financial support, often from the child's father or from a relative. Few of them came by themselves. In those days, only women who used the maternity hospital free of charge would have been as isolated in the difficult perinatal period as are women today who choose to deliver their babies anonymously. PMID:25134255

  13. Friedrich Miescher Prize awardee lecture review. A conserved family of nuclear export receptors mediates the exit of messenger RNA to the cytoplasm.

    PubMed

    Izaurralde, E

    2001-07-01

    The distinguishing feature of eukaryotic cells is the segregation of RNA biogenesis and DNA replication in the nucleus, separate from the cytoplasmic machinery for protein synthesis. As a consequence, messenger RNAs (mRNAs) and all cytoplasmic RNAs from nuclear origin need to be transported from their site of synthesis in the nucleus to their final cytoplasmic destination. Nuclear export occurs through nuclear pore complexes (NPCs) and is mediated by saturable transport receptors, which shuttle between the nucleus and cytoplasm. The past years have seen great progress in the characterization of the mRNA export pathway and the identification of proteins involved in this process. A novel family of nuclear export receptors (the NXF family), distinct from the well-characterized family of importin beta-like proteins, has been implicated in the export of mRNA to the cytoplasm.

  14. Knowledge Management to Exploit Agrarian Resources as Part of Late-Eighteenth-Century Cultures of Innovation: Friedrich Casimir Medicus and Franz Von Paula Schrank

    ERIC Educational Resources Information Center

    Popplow, Marcus

    2012-01-01

    This essay contributes to a recent strain of research that questions clear-cut dichotomies between "scientists" and "artisans" in the early modern period. With a focus on the exploitation of agrarian resources, it argues for the appreciation of a more complex panorama of intersecting knowledge systems spanning from botany as part of natural…

  15. Friedrich Miescher Prize awardee lecture review. A conserved family of nuclear export receptors mediates the exit of messenger RNA to the cytoplasm.

    PubMed

    Izaurralde, E

    2001-07-01

    The distinguishing feature of eukaryotic cells is the segregation of RNA biogenesis and DNA replication in the nucleus, separate from the cytoplasmic machinery for protein synthesis. As a consequence, messenger RNAs (mRNAs) and all cytoplasmic RNAs from nuclear origin need to be transported from their site of synthesis in the nucleus to their final cytoplasmic destination. Nuclear export occurs through nuclear pore complexes (NPCs) and is mediated by saturable transport receptors, which shuttle between the nucleus and cytoplasm. The past years have seen great progress in the characterization of the mRNA export pathway and the identification of proteins involved in this process. A novel family of nuclear export receptors (the NXF family), distinct from the well-characterized family of importin beta-like proteins, has been implicated in the export of mRNA to the cytoplasm. PMID:11529502

  16. PREFACE: 31st European Physical Society Conference on Plasma Physics

    NASA Astrophysics Data System (ADS)

    Dendy, Richard

    2004-12-01

    Universiteit Eindhoven, Netherlands Dr Martin Lampe Naval Research Laboratory, Washington DC, USA Dr Jo Lister Centre de Recherches en Physique des Plasmas, Lausanne, Switzerland Dr Paola Mantica Istituto di Fisica del Plasma, Milan, Italy Professor Tito Mendonca Instituto Superior Tecnico, Lisbon, Portugal Dr Patrick Mora École Polytechnique, Palaiseau, France Professor Lennart Stenflo Umeå Universitet, Sweden Professor Paul Thomas CEA Cadarache, Saint-Paul-lez-Durance, France Professor Friedrich Wagner Max-Planck-Institut fr Plasmaphysik, Garching, Germany Professor Hannspeter Winter Technische Universität Wien, Austria

  17. Neuronal Spoken Word Recognition: The Time Course of Processing Variation in the Speech Signal

    ERIC Educational Resources Information Center

    Schild, Ulrike; Roder, Brigitte; Friedrich, Claudia K.

    2012-01-01

    Recent neurobiological studies revealed evidence for lexical representations that are not specified for the coronal place of articulation (PLACE; Friedrich, Eulitz, & Lahiri, 2006; Friedrich, Lahiri, & Eulitz, 2008). Here we tested when these types of underspecified representations influence neuronal speech recognition. In a unimodal…

  18. When One Biographer "Borrows" from Another, the Dispute Gets Philosophical

    ERIC Educational Resources Information Center

    Shea, Christopher

    2012-01-01

    Mark Anderson, a professor of philosophy at Belmont University, publishes an account of Nietzsche's life and work. He remembered liking "Friedrich Nietzsche" (Overlook Press, 2005), by the late independent scholar Curtis Cate, so he started rereading that one. But then he had second thoughts. After all, "Friedrich Nietzsche: A Philosophical…

  19. Struve family

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Struve, Friedrich Georg Wilhelm (1793-1864); Struve, Otto Wilhelm (1819-1905), son of Friedrich; Struve, Karl Hermann (1854-1920), elder son of Otto Wilhelm, brother of Gustav; Struve, Gustav Wilhelm Ludwig (1858-1920), younger son of Otto Wilhelm, brother of Karl; Struve, Otto (1897-1963) [Otto Struve II], son of Gustav....

  20. A chemist's legacy

    NASA Astrophysics Data System (ADS)

    Ebach, Malte C.

    2016-09-01

    Although Friedrich Stromeyer is best remembered for writing one of the founding works in plant geography -- the forerunner to modern-day biogeography -- his contributions to chemistry should not be underestimated, argues Malte C. Ebach.

  1. Killing Initial Data on spacelike conformal boundaries

    NASA Astrophysics Data System (ADS)

    Paetz, Tim-Torben

    2016-08-01

    We analyze Killing Initial Data on Cauchy surfaces in conformally rescaled vacuum space-times satisfying Friedrich's conformal field equations. As an application, we derive the KID equations on a spacelike ℐ-.

  2. The Black Forest in a Bamboo Garden: Missionary Kindergartens in Japan, 1868-1912.

    ERIC Educational Resources Information Center

    Wollons, Roberta

    1993-01-01

    Traces the history of kindergartens in Japan. Maintains that the Japanese government embraced the concept and modified it to encourage modernization. Includes 10 photographs of wood block prints showing how Friedrich Froebel's moral lessons were replicated in Japanese settings. (CFR)

  3. Aesthetic Bildung in Vocational Education: The Biographical Case of Bookbinding Master Wolfgang B. and His Apprenticeship

    ERIC Educational Resources Information Center

    Tyson, Ruhi

    2014-01-01

    In the present article I will be discussing the importance attributed to aesthetic experiences in the vocational education of bookbinding master Wolfgang B. using the philosophy of Friedrich Schiller both to understand what constitutes these processes and to examine Schiller's thoughts in the light of his recollections. By doing this I hope…

  4. Parts of Antarctica's King George Island are littered with trash

    NASA Astrophysics Data System (ADS)

    Kumar, Mohi

    2013-02-01

    A report released 7 February by ecologists from Germany's Friedrich Schiller University Jena reveals that parts of King George Island, a logistical hub for international research in Antarctica, are home to open pits of trash, decaying field huts, and other forms of pollution.

  5. Konkordanz zu Schillers aesthetischen und philosophischen Schriften (Concordance of Schiller's Aesthetic and Philosophical Writings).

    ERIC Educational Resources Information Center

    Sanford, Gerlinde Ulm

    This document provides a computer-based concordance of the vocabulary used in Friedrich von Schiller's "Aesthetic and Philosophical Writings" as they appear in Volumes 20 and 21 of Schiller's "Werke," 1967 edition, edited by Benno von Wiese. The first section includes the entire text, each sentence numbered for research purposes. The second…

  6. None So Blind: Early Childhood Education and Care--The Connective Tissue

    ERIC Educational Resources Information Center

    Gammage, Philip

    2007-01-01

    The author makes sense of the story of his professional life through the eyes of several important writers and teachers on education and says that, for him, Bridget Plowden ranks alongside John Dewey, Friedrich Froebel, Ben Morris and A.S. Neill.

  7. Instinct & Imagination: Froebel's Principal of Self-Activity in Turn-of-the-Century Song Books.

    ERIC Educational Resources Information Center

    Alper, Clifford D.

    1985-01-01

    Children's natural endeavors that enable them to attain self-realization and fulfillment were given the name "self-activity" by the German philosopher Friedrich Froebel. Discussed are components traceable to the self-activity principle that appear in early childhood song materials published around the turn of the century. (RM)

  8. Mental Maps and Ethnocentrism: Geographic Characterizations in the Past.

    ERIC Educational Resources Information Center

    Elliott, Harold M.

    1979-01-01

    Reexamines geographic thought regarding ethnocentrism as expressed in the writings including Ellen Churchill Semple, Hendrick Willem Van Loon, Ellsworth Huntington, Roswell C. Smith, J. Olney, Henry Thomas Buckle, Georg Friedrich Hegel, Johann Gottfried Von Herder, Charles de Montesquieu, Ibn Khaldun, and Hippocrates. (DB)

  9. Marxisms as Utopias: Evolving Ideologies.

    ERIC Educational Resources Information Center

    Wallerstein, Immanuel

    1986-01-01

    Contends that there have been three stages or eras of social science: the philosophic, the scientific, and the as yet unnamed present era. Maintains that the three eras match, in chronological development, the successive periods of Marxian thought and the three different views of utopia offered by Thomas More, Friedrich Engels, and Karl Mannheim.…

  10. Marxism and Communication.

    ERIC Educational Resources Information Center

    Daley, Patrick J.; Soloski, John

    Karl Marx and Friedrich Engels had little to say specifically about communication and language, but their works hint at the direction their critique of communication might have taken. Language and consciousness are conditioned by specific means of production and sociopolitical circumstances and are therefore ideological. The domain of ideology…

  11. 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.

  12. Reprint Series: Memorable Personalities in Mathematics: Nineteenth Century. RS-11.

    ERIC Educational Resources Information Center

    Schaaf, William L., Ed.

    This is one in a series of SMSG supplementary and enrichment pamphlets for high school students. This series makes available expository articles which appeared in a variety of mathematical periodicals. Topics covered include: (1) Laplace; (2) Carl Friedrich Gauss; (3) Wolfgang and Johann Bolyai; (4) Evariste Galois; and (5) Josiah Willard Gibbs.…

  13. Validating a Psychology as a Helping Profession Scale

    ERIC Educational Resources Information Center

    Gervasio, Amy Herstein; Wendorf, Craig A.; Yoder, Natalie F.

    2010-01-01

    We developed an 11-item Psychology as a Helping Profession (PHP) scale that measured aspects of personal growth/helping skills and applied helping. The scale was only weakly correlated with Friedrich's (1996) Psychology as Science (PAS) scale, implying that the 2 scales measure different conceptions of the nature of psychology. Psychology majors…

  14. "Like Sending Coals to Newcastle": Impressions from and of the Anglo-American Kindergarten Movements

    ERIC Educational Resources Information Center

    Nawrotzki, Kristen D.

    2007-01-01

    Developed by the German pedagogue Friedrich Froebel (1782-1852), the Kindergarten offered a revolutionary educational program for young children. In the mid-nineteenth century, after several decades of limited success in the German states, Froebel's Kindergarten began to be transplanted to other countries, including the USA and England. The…

  15. Kafka: A Collection of Critical Essays. Twentieth Century Views Series.

    ERIC Educational Resources Information Center

    Gray, Ronald, Ed.

    One of a series of works aimed at presenting contemporary critical opinion on major authors, this collection includes essays by Ronald Gray, Edwin Muir, Friedrich Beissner, R. O. C. Winkler, Johannes Pfeiffer, Caroline Gordon, Idris Parry, Edmund Wilson, Erich Heller, Austin Warren, Eliseo Vivas, Albert Camus, Martin Buber, and H. S. Reiss--all…

  16. "Their Little Wooden Bricks": A History of the Material Culture of Kindergarten in the United States

    ERIC Educational Resources Information Center

    Prochner, Larry

    2011-01-01

    This article explores the material culture of kindergarten in the United States in relation to the production and consumption of materials and kindergarten theory and pedagogy. The focus is on Friedrich Froebel's building gifts as they were manufactured and sold by the Milton Bradley Company from 1869 to 1939. A review of trade catalogues over the…

  17. Kindergarten.

    ERIC Educational Resources Information Center

    Hill, Patty Smith

    This reprint of an encyclopedia article describes the history of kindergarten education through approximately 1940. Kindergarten is defined as "a specialized school adapted to the nature and needs of young children from the fourth to the sixth year." Kindergarten was originated by Friedrich Froebel in Germany around 1840. Froebel's predecessors…

  18. Love and Ruin(s): Robert Frost on Moral Repair

    ERIC Educational Resources Information Center

    Frank, Jeff

    2011-01-01

    This essay begins where Alasdair MacIntyre's "After Virtue" begins: facing a moral world in ruin. MacIntyre argues that this predicament leaves us with a choice: we can follow the path of Friedrich Nietzsche, accepting this moral destruction and attempting to create lives in a rootless, uncertain world, or the path of Aristotle, working to reclaim…

  19. A Study of the Holocaust, Student Readings. Third Edition.

    ERIC Educational Resources Information Center

    Des Moines Public Schools, IA.

    This book of student readings is intended to provide factual information on the Holocaust and help students understand the importance of individual choice and responsibility for the people of a free society. Topics covered include: (1) "Racism and Anti-Semitism in Germany"; (2) an excerpt from "Friedrich" by Hans Peter Richter (Holt, Rinehart &…

  20. Learning through Literature: Historical Fiction, Autobiography, and the Holocaust.

    ERIC Educational Resources Information Center

    Short, Geoffrey

    1997-01-01

    Argues against the common-sense view that children's literature dealing with the Jews in Nazi Germany is necessarily useful as an aid to studying the Holocaust. Finds a number of significant issues overlooked in the classroom. Discusses the novel "Friedrich" by H.P. Richter. (PA)

  1. The Origin of the s, p, d, f Orbital Labels

    ERIC Educational Resources Information Center

    Jensen, William B.

    2007-01-01

    The theory of s, p, d and f dealing with the line spectra of the alkali metals during the period 1881 based on analogies with the harmonic ratios of sound is described. Friedrich Hund followed Bohr's practice of labelling the various shells and subshells by replacing the secondary quantum number with the series notations (s, p, d, and f), which…

  2. Teachers Unions at Risk of Losing "Agency Fees"

    ERIC Educational Resources Information Center

    Antonucci, Mike

    2016-01-01

    For 50 years, American education policy has often danced to the tune of labor realities. "Friedrichs v. California Teachers Association" is a case that awaits hearing by the U.S. Supreme Court that could dramatically change this picture. The case, if decided for the plaintiffs, could end the practice of "agency" fees--money…

  3. Changing Images of Childhood. Issues in Education.

    ERIC Educational Resources Information Center

    Goellner, Lydia A.

    2000-01-01

    Examines the changing images of childhood throughout history, focusing on how changes are reflected in beliefs and educational and social practices toward children with special needs. Describes impact of a painful childhood on Friedrich Froebel and actor Cary Grant. Suggests ways to enhance children's lives, including government subsidized…

  4. LAYER DEPENDENT ADVECTION IN CMAQ

    EPA Science Inventory

    The advection methods used in CMAQ require that the Courant-Friedrichs-Lewy (CFL) condition be satisfied for numerical stability and accuracy. In CMAQ prior to version 4.3, the ADVSTEP algorithm established CFL-safe synchronization and advection timesteps that were uniform throu...

  5. Froebel Is Dead; Long Live Froebel! The National Froebel Foundation and English Education

    ERIC Educational Resources Information Center

    Nawrotzki, Kristen D.

    2006-01-01

    The German pedagogue Friedrich Froebel lived from 1782 to 1852. The pedagogy that made Froebel famous was encompassed in his Kindergarten, a set of strictly defined methods and activities for the education of young children, which he developed and refined in the second quarter of the nineteenth century. Froebel's Kindergarten reached England in…

  6. Making College More Expensive: The Unintended Consequences of Federal Tuition Aid. Policy Analysis. No. 531

    ERIC Educational Resources Information Center

    Wolfram, Gary

    2005-01-01

    As Congress debates the reauthorization of the Higher Education Act (HEA), it should heed Friedrich Hayek's warning that democracy is "peculiarly liable, if not guided by accepted common principles, to produce over-all results that nobody wanted." One result of the federal government's student financial aid programs is higher tuition costs at the…

  7. Art, Water, and the Environment: Hundertwasser and Ukiyo-e

    ERIC Educational Resources Information Center

    Stephens, Pam

    2005-01-01

    This brief article explores the work of Friedrich Stowasser (1928-2000), an Austrian artist who modified his name throughout his career, eventually settling upon the invented name of Friedensreich Hundertwasser. Both Hundertwasser's original Slavic surname and his invented surname mean about the same: hundred waters. Both names illustrate the…

  8. 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…

  9. European Influences on the Theory and Philosophy of Viktor Lowenfeld.

    ERIC Educational Resources Information Center

    Michael, John A.; Morris, Jerry W.

    1985-01-01

    Discusses how the work of art theorists, art educators, psychologists, and anthropologists who were predecessors or contemporaries of Viktor Lowenfeld influenced Lowenfeld's philosophy and theory of art education. Included are Friedrich Froebel, James Sully, Franz Cizek, Siegfried Levinstein, Max Verworn, Walter Krotzsch, George Luquet, and Karl…

  10. Discussions on Some Educational Issues III. Research Report 94.

    ERIC Educational Resources Information Center

    Kansanen, Pertti, Ed.

    This publication consists of eight articles in which contributors discuss the following educational issues: (1) "Prospects for Schooling" (Friedrich W. Busch); (2) "Broadcasting, Education and Active Citizenship" (Brian Groombridge); (3) "On the Role of Mother-tongue Education in Multilingual Societies" (Wilfried Hartmann); (4) "Theory, Practice…

  11. The Froebelian Kindergarten as an International Movement.

    ERIC Educational Resources Information Center

    Hewes, Dorothy W.

    This paper presents an overview of the educational principles of Friedrich Froebel and indicates how the Froebelian approach was introduced into Israel. The modern aspects of Froebel's ideas are emphasized as well as scientistic distortions in their implementation. Recommendations to practitioners for improving early childhood education are…

  12. Those First Good Years of Indian Education: 1894-1898.

    ERIC Educational Resources Information Center

    Hewes, Dorothy W.

    1981-01-01

    As Superintendent of Indian Schools from 1894 through 1897, William Hailmann incorporated into the curriculum his "New Education," a system based on the philosophy of Friedrich Froebel and similar to modern "open education" and to some current model programs in Indian education. (CM)

  13. Child-Centered Education for Pacific-Rim Cultures?

    ERIC Educational Resources Information Center

    Jackson, Peter W.

    1998-01-01

    Argues for a cautious approach to transplanting theory from one culture to another, particularly considering the case for applying Friedrich Froebel's child-centered theory to early childhood education in Pacific Rim cultures. Uses a historical approach to distinguish three distinct versions of the theory, the Christian, the Progressive, and the…

  14. Sisterhood and Sentimentality: Americas's Earliest Preschool Centers.

    ERIC Educational Resources Information Center

    Hewes, Dorothy W.

    1995-01-01

    Describes how America's oldest child-care centers began during a period of economic growth and intellectual turbulence in the late 1800s, when women from all walks of American life united to promote the kindergarten movement inspired by the German Friedrich Froebel. Chronicles the movement from a women's history perspective. (ET)

  15. Neue Lautzeichen im Advanced Learners Dictionary (ALD). Stellungnahmen zum Pro und Kontra (New Sound Symbols in the Advanced Learners Dictionary [ALD]. Considerations Pro and Con)

    ERIC Educational Resources Information Center

    Zielsprache Englisch, 1976

    1976-01-01

    The phonetic symbols in the "Advanced Learners Dictionary" (Oxford University Press, London) are discussed critically in articles by L. Alfes, H. Arndt, E. Bauch, G. Dahlmann-Resing, W. Friedrich, E. Germer, B. Haycraft, H. P. Kelz. Reference is made to an earlier article "Neue Zeichen", by H. G. Hoffmann. (Text is in German.) (IFS/WGA)

  16. The Kindergarten in Germany and the United States, 1840-1914: A Comparative Perspective

    ERIC Educational Resources Information Center

    Allen, Ann Taylor

    2006-01-01

    Kindergarten pedagogy, which was based on educational play and cognitive development, was designed by the German Friedrich Frobel in the 1840s to train the future citizens of the new state that liberals aspired to create. It created a professional role for women, whom Frobel believed were innately gifted teachers of young children. German…

  17. Burke, Nietzsche, Lacan: Three Perspectives on the Rhetoric of Order.

    ERIC Educational Resources Information Center

    Thomas, Douglas

    1993-01-01

    Examines the complex relationship between rhetoric and order in the works of Kenneth Burke, Friedrich Nietzsche, and Jacques Lacan. Argues for three differing, yet complementary, views of rhetoric and order, each having a corresponding epistemology and axiology. Concludes with an analysis of the construction of order in Thomas Hobbe's "Leviathan."…

  18. The First Treatise in Comparative Education Rediscovered

    ERIC Educational Resources Information Center

    Lenhart, Volker

    2016-01-01

    The Latin essay "De re Scholastica Anglica cum Germanica Comparata" (English and German school education compared) published in 1795-1798 by the Freiberg/Saxony grammar school principal Friedrich August Hecht is the first treatise in comparative education. The rediscovery of the text, its earlier mentioning in the history of comparative…

  19. Violence.

    ERIC Educational Resources Information Center

    Council of Europe Forum, 1985

    1985-01-01

    Highlighting the issue of violence, this Forum issue contains 12 essays. Titles and authors are: "Passivity in the Face of Violence" (Henri Laborit); "Democratisation without Violence?" (Friedrich Hacker); "Ritualised Violence in Sport" (Christian Bromberger); "Violence in Prisons" (Luige Daga); "Racial Aggression" (Geoffrey Bindman); "Violence in…

  20. Schopenhauer, Nietzsche, and the Aesthetically Sublime

    ERIC Educational Resources Information Center

    Vandenabeele, Bart

    2003-01-01

    Much has been written on the relationship between Arthur Schopenhauer and Friedrich Nietzsche. Much remains to be said, however, concerning their respective theories of the sublime. In this article, the author first argues against the traditional, dialectical view of Schopenhauer's theory of the sublime that stresses the crucial role the sublime…

  1. A (R)evaluation of Nietzsche's Anti-Democratic Pedagogy: The Overman, Perspectivism, and Self-Overcoming

    ERIC Educational Resources Information Center

    Jonas, Mark E.

    2009-01-01

    In this paper, I argue that Friedrich Nietzsche's concept of self-overcoming has been largely misinterpreted in the philosophy of education journals. The misinterpretation partially stems from a misconstruction of Nietzsche's perspectivism, and leads to a conception of self-overcoming that is inconsistent with Nietzsche's educational ideals. To…

  2. The madness of Nietzsche: a misdiagnosis of the millennium?

    PubMed

    Cybulska, E M

    2000-08-01

    This article represents a personal discussion about Nietzsche's mental illness, which formed part of a larger paper 'The masks of Nietzsche and eternal return of the repressed'. This was presented at the 6th Annual Conference of The Friedrich Nietzsche Society, September 1996, Manchester UK, as reported by Nussbaumer-Benz (1998).

  3. Taking Up Space: Museum Exploration in the Twenty-First Century

    ERIC Educational Resources Information Center

    Sutton, Tiffany

    2007-01-01

    Museums have become a crucible for questions of the role that traditional art and art history should play in contemporary art. Friedrich Nietzsche argued in the nineteenth century that museums can be no more than mausoleums for effete (fine) art. Over the course of the twentieth century, however, curators dispelled such blanket pessimism by…

  4. On the Need for Dionysian Education in Schools Today

    ERIC Educational Resources Information Center

    Steel, Sean

    2014-01-01

    Although much has been written about Friedrich Nietzsche's views on education over the years, and much has also been written about Dionysus, god of wine and ecstasy, very little attention has been given to the meaning of, and need for, Dionysian education. In this article, Sean Steel attempts to begin that project. Drawing Nietzsche's…

  5. Montaigne, Nietzsche, and the Mnemotechnics of Student Agency

    ERIC Educational Resources Information Center

    Bingham, Charles

    2007-01-01

    This essay explores the educational implications of the thought of Michel de Montaigne and Friedrich Nietzsche on the subject of memory. It explores the sorts of cultural memory practices that Nietzsche has called "mnemotechnics", that is, the aspects of memory use that allow human beings to live life more fully. Nietzsche and Montaigne's work is…

  6. The Politics of Encyclopaedias

    ERIC Educational Resources Information Center

    Fozooni, Babak

    2012-01-01

    The paper assesses the political credibility of three encyclopaedias (Encyclopaedia Britannica, Encyclopedia of Marxism and Wikipedia) in relation to three chosen topics (Friedrich Engels's biography; the political philosophy of fascism; and, the discipline of social psychology). I was interested in discerning how entries are represented and…

  7. Quasioptimality of some spectral mixed methods

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, Jayadeep; Demkowicz, L. F. Leszek F.

    2004-05-01

    In this paper, we construct a sequence of projectors into certain polynomial spaces satisfying a commuting diagram property with norm bounds independent of the polynomial degree. Using the projectors, we obtain quasioptimality of some spectral mixed methods, including the Raviart-Thomas method and mixed formulations of Maxwell equations. We also prove some discrete Friedrichs type inequalities involving curl.

  8. The Potentiation of Meaning through Translative Reading: Poetic Translation and the Case of Gottfried Benn

    ERIC Educational Resources Information Center

    Morgan, Ian Egon

    2009-01-01

    The theory of literary translation has been plagued by a disregard of the comprehensive aspect of the task since its inception, largely focusing on the challenges of the expressive aspect instead. This development throughout the history of translation--with the notable exceptions of Martin Luther and Friedrich Schleiermacher--has led to…

  9. Writing with Light: Jacob Riis's Ambivalent Exposures

    ERIC Educational Resources Information Center

    Carter, Christopher

    2008-01-01

    The current interest in multimodal rhetoric was anticipated by Jacob Riis's social documentary texts and presentations during the late nineteenth and early twentieth centuries. In contrast with the socialist urban critiques presented by Friedrich Engels, Riis's work demonstrated profound ambivalence toward the city's poor. While calling for reform…

  10. "Groundhog Day, Deja Vu," and the Myth of the Eternal Recurrence.

    ERIC Educational Resources Information Center

    Voeltz, Richard A.

    1998-01-01

    Reveals that through the use of the movie "Groundhog Day," students in humanities courses can grasp Friedrich Nietzsche's myth of eternal recurrence; the myth addresses the question of what if everything that occurred in one's life occurred again just as it happened before. Discusses the similarities between Nietzsche's myth and the movie. (CMK)

  11. Payback Time? Discourses of Lack, Debt and the Moral Regulation of Teacher Education

    ERIC Educational Resources Information Center

    Beighton, Chris

    2016-01-01

    This paper analyses recent policy and discourse in the UK lifelong learning sector to identify a tension in discourse which positions teacher educators as essential to the knowledge economy while simultaneously insisting on the deficits they represent. Drawing on critical analyses from Friedrich Nietzsche, Maurizio Lazzarato and Gilles Deleuze, I…

  12. Revitalising "Bildsamkeit"?

    ERIC Educational Resources Information Center

    Saeverot, Herner

    2016-01-01

    In the book "Forgotten Connections. On Culture and Upbringing," originally from 1983, the late German educator Klaus Mollenhauer interprets Johann Friedrich Herbart's educational concept of "Bildsamkeit", i.e., the ability and willingness to be educated. Furthermore, Mollenhauer conceives "Bildsamkeit" as growing out…

  13. The "Encounter" as an "Event of Truth" in Education: An Anthropological-Pedagogical Approach

    ERIC Educational Resources Information Center

    Pantazis, Vasileios E.

    2012-01-01

    In this essay, Vasileios Pantazis examines how two philosophers having different orientations acknowledge and study the phenomenon of the "encounter" ("Begegnung") and its fundamental importance to human life and education. On the one hand, Otto Friedrich Bollnow drew on existential philosophy and philosophical anthropology in his analysis of the…

  14. A Reflection on Educating College Students about the Value of Public-Sector Unions

    ERIC Educational Resources Information Center

    Mooney, Christine; Volchok, Edward

    2016-01-01

    This year, labor unions got a reprieve: The Supreme Court deadlocked in a much-anticipated case that could have turned almost every state into Wisconsin, where partisan interests have crippled union power. The case, "Friedrichs vs. California Teachers Association," addressed a previous case, "Abood v. Detroit Board of…

  15. An English Course in Science and Humanities.

    ERIC Educational Resources Information Center

    Reno, Robert P.

    1979-01-01

    One way in which changing attitudes toward scientific knowledge and technology can be made the focus of attention in a college literature course is suggested by this analysis of Christopher Marlowe's "Doctor Faustus," Mary Shelley's "Frankenstein," and Friedrich Durrenmatt's "The Physicists." (JMD)

  16. "We create chemistry for a sustainable future": chemistry creates sustainable solutions for a growing world population.

    PubMed

    Kreimeyer, Andreas; Eckes, Peter; Fischer, Christian; Lauke, Harald; Schuhmacher, Peter

    2015-03-01

    On April 6, 1865, Friedrich Engelhorn founded the company "Badische Anilin- & Sodafabrik" in Mannheim, Germany. This Essay, commemorating the 150th anniversary of BASF, introduces several outstanding examples of innovation from the history of BASF and highlights how chemical and technical competencies developed in the past still play an essential role in current projects.

  17. The "Hard Problem" and the Quantum Physicists. Part 2: Modern Times

    ERIC Educational Resources Information Center

    Smith, C. U. M.

    2009-01-01

    This is the second part of a review of the work of quantum physicists on the "hard part" of the problem of mind. After an introduction which sets the scene and a brief review of contemporary work on the neural correlates of consciousness (NCC) the work of four prominent modern investigators is examined: J.C. Eccles/Friedrich Beck; Henry Stapp;…

  18. Burckhard F. Kommerell and Kommerell's Diverticulum

    PubMed Central

    van Son, Jacques A.M.; Konstantinov, Igor E.

    2002-01-01

    Burckhard Friedrich Kommerell's scholarly description of the aortic diverticulum that bears his name was published in 1936. In the international literature, however, the name of Kommerell survives only as an eponym. We present biographical information about Kommerell, as supplied by family members, and comment on the surgical relevance of his 1936 report. (Tex Heart Inst J 2002;29:109–12) PMID:12075866

  19. Froebel and the Rise of Educational Theory in the United States

    ERIC Educational Resources Information Center

    Baader, Meika Sophia

    2004-01-01

    This contribution compares entries on Friedrich Froebel and the kindergarten in German and United States' histories of education from 1857 to 1933. In the American histories, Froebel appears as the great "hero" of education of the 19th century, whereas in the German histories, Pestalozzi is the "hero." This difference in the perspectives goes back…

  20. Reuniting Art and Nature in the Life of the Child

    ERIC Educational Resources Information Center

    Strauch-Nelson, Wendy

    2012-01-01

    Sometimes looking at the history of education can be a bit frustrating. Examination of the past is necessary, however, if people are to move forward responsibly for the sake of the child. In this article, the author examines the common ancestry of the kindergarten, art, and nature study. As the founder of the kindergarten, Friedrich Froebel played…

  1. Impossible Geometric Constructions: A Calculus Writing Project

    ERIC Educational Resources Information Center

    Awtrey, Chad

    2013-01-01

    This article discusses a writing project that offers students the opportunity to solve one of the most famous geometric problems of Greek antiquity; namely, the impossibility of trisecting the angle [pi]/3. Along the way, students study the history of Greek geometry problems as well as the life and achievements of Carl Friedrich Gauss. Included is…

  2. Sand Face: Humanism after Antihumanism

    ERIC Educational Resources Information Center

    Arcilla, René V.

    2015-01-01

    Have the critiques of humanism of the 1960s and 1970s buried this idea once and for all? Or is there a way that humanism can absorb some of this antihumanist thinking and thereby renew itself? Drawing on writings of Michel Foucault, Charles Taylor, Friedrich Nietzsche, and Martin Heidegger in order to illuminate artworks by Robert Smithson and…

  3. Froebel and Early Childhood Education in America.

    ERIC Educational Resources Information Center

    Sniegoski, Stephen J.

    The idea of a special type of education for young children emerged in the United States in the mid-nineteenth century, with the kindergarten movement. The kindergarten was created by Friedrich Froebel, the German educator whose ideas, although no longer popular, can be traced to contemporary early childhood education. Froebel explicitly rejected…

  4. Rediscovering Froebel: A Call to Re-Examine His Life and Gifts

    ERIC Educational Resources Information Center

    Manning, John P.

    2005-01-01

    This article examines the life of Friedrich Froebel, the founder of the kindergarten movement and his first 10 "gifts to children." The author suggests that Froebel's philosophy of German Romanticism caused the waning use of his methods. He continues to state that Froebel's development of instructional material and structured play-based curricula…

  5. "Translated, It Is: …"--An Ethics of Transreading

    ERIC Educational Resources Information Center

    Zhang, Huiwen

    2014-01-01

    Inspired by Friedrich Nietzsche's idea of philology and William Gass's concept of transreading, Huiwen (Helen) Zhang employs "transreader" to suggest the integration of four roles in one: reader, translator, writer, and scholar. "Transreader" recognizes that close reading, literary translation, creative writing, and…

  6. Lifestyle and Landscapes: The Element of Culture in Geography

    ERIC Educational Resources Information Center

    Ballas, Donald J.

    1978-01-01

    Addressing the study of man/land relationships, this article discusses the following: cultural geography, environmental determinism (a la Friedrich Ratzel), "possibilism" (a la Paul Vidal de la Balche), cultural landscapes (a distinction is made between cultural and natural landscapes), and environmental perception. (JC)

  7. Meeting Standards in the Changing Landscape of Today's Kinder"garden"

    ERIC Educational Resources Information Center

    McLennan, Deanna Pecaski

    2011-01-01

    First conceptualized by Friedrich Froebel as a "children's garden," kindergarten classrooms in Canada today emphasize play and exploration as the primary methods of learning and development. This garden provides multiple opportunities for children to become lost in spontaneous play and creative interactions with peers. Kindergarten has slowly…

  8. If We Knew What Spirituality Was, We Would Teach for It

    ERIC Educational Resources Information Center

    Yob, Iris M.

    2011-01-01

    Two extraordinary recent experiences that the author would call highly "spiritual" are explored against the background of ideas provided by writers such as Friedrich Schleiermacher, Rudolf Otto, Paul Tillich, and Abraham Maslow to unpack what spirituality is, with particular attention to the emotions and the insights involved in spirituality. The…

  9. The Riemann Zeta Zeros from an Asymptotic Perspective

    ERIC Educational Resources Information Center

    Grant, Ken

    2015-01-01

    In 1859, on the occasion of being elected as a corresponding member of the Berlin Academy, Bernard Riemann (1826-66), a student of Carl Friedrich Gauss (1777-1855), presenteda lecture in which he presented a mathematics formula, derived from complex integration, which gave a precise count of the primes on the understanding that one of the terms in…

  10. Political "Bildung" in the Context of Discipline, Instruction, and Moral Guidance

    ERIC Educational Resources Information Center

    Rucker, Thomas

    2014-01-01

    Johann Friedrich Herbart (1776-1841) is considered the founding father of the science of education. In this article, I will try to show that Herbart sees the promotion of political "Bildung" as the task of discipline, instruction, and moral guidance, and that his work presents important components of a theory of political…

  11. Chickens across the Curriculum: An Experiment in Experiential Learning.

    ERIC Educational Resources Information Center

    Poulsen, Kristin; And Others

    This paper describes: (1) the experiences of a class of 6- and 7-year-old students as they designed and built a small farm on the Laboratory School grounds at Berry College (Georgia); (2) the understanding that comes with the relevant and meaningful experience of building a farm and raising animals; (3) the infusion of Friedrich Froebel's…

  12. [Considering all facets of man].

    PubMed

    Quentin, Bertrand

    2012-01-01

    Michel Foucault and Erving Goffman, through their works, questioned the notion of mental illness as well as traditional psychiatry. However, Friedrich Hegel, in reference to Philippe Pinel and to "human treatment" is opposed to any unilateral model which would tend to exclude the institution, insanity and therefore the patient.

  13. Between Knowledge and "Plagiarism," or, How the Chinese Language Was Studied in the West

    ERIC Educational Resources Information Center

    Tong, Q. S.

    2008-01-01

    This article looks at descriptions of the Chinese language in Western intellectual writings as indicative of a particular process of knowledge formation and reproduction. Beginning with the first systematic account produced by Matteo Ricci (1552-1610), it charts views offered by John Wilkins (1614-1672), James Beattie (1735-1803), Friedrich von…

  14. [Schiller and the history of medicine].

    PubMed

    Schäfer, Daniel; Neuhausen, Karl August

    2014-01-01

    Friedrich Schiller (1759-1805), one of the most renowned German poets, also received a professional training (1776-80) as surgeon at the military academy at Stuttgart. It is almost unknown that Schiller received a formal education in medical history during the first year of his academic curriculum. His exam in medical history included the public defense of 38 Latin theses presenting historical interpretations, philological criticism and an evaluation of 18th century medicine side by side. These theses had been compiled by his teacher Johann Friedrich Consbruch, who recommended an eclectic use of contemporary knowledge and was an adherent of Haller's experimental medicine. This paper presents a thorough examination of these doctrines in historical perspective. As our investigation shows, at Schiller's time medical history as an academic discipline was primarily used to emphasize medicine's significance as a healing art and to ascertain the practicing physician's professional identity.

  15. Wide-Field Plate Archive of the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Poghosyan, A. V.; Pfau, W.; Tsvetkova, K. P.; Mugrauer, M.; Tsvetkov, M. K.; Hambaryan, V. V.; Neuhäuser, R.

    We present the archive of the wide-field plate observations obtained at the University Observatory Jena, which is stored at the Astrophysical Institute of the Friedrich Schiller University Jena. The archive contains plates taken in the period February 1963 to December 1982 with the 60/90/180-cm Schmidt telescope of the university observatory. A computer-readable version of the plate metadata catalogue (for 1257 plates), the logbooks, as well as the digitized Schmidt plates in low and high resolution are now accessible to the astronomical community.This paper describes the properties of the archive, as well as the processing procedure of all plates in detail. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich Schiller University.

  16. [Clinical dermatology at the Central Hospital Sankt-Jürgen-Strasse in Bremen.. A 110-year history].

    PubMed

    Bahmer, F A

    2001-08-01

    The history of clinical dermatology in Bremen began in 1891 with a dermatology unit founded in the main building of the then so-called "Big Hospital", nowadays Central Hospital Sankt-Juergen-Street. Friedrich B. Hahn became the first director and served in this position for more than four decades. In 1913, the dermatology wards moved to a new building, still home to the Dermatologic Clinic today. In 1933, the son of F.B. Hahn, Carl F. Hahn, became director until 1938, when the state officials named Konrad Burchardi as head of the department. Immediately after World War II, Friedrich Fölsch replaced K. Burchardi. He served as director until his retirement in 1964, when Joachim J. Herzberg became his successor until 1979. Wolfgang P. Herrmann then directed the clinic until 1994, when the author of this article was elected.

  17. 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.

  18. FIASCO: A new spectrograph at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.; Avila, G.

    2009-05-01

    A new spectrograph (FIASCO) is in operation at the 0.9 m telescope of the University Observatory Jena. This article describes the characterization of the instrument and reports its first astronomical observations, among those lithium (6708 Å) detection in the atmosphere of young stars, and the simultaneous photometric and spectroscopic monitoring of variable stars. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  19. CTK: A new CCD Camera at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.

    2009-05-01

    The Cassegrain-Teleskop-Kamera (CTK) is a new CCD imager which is operated at the University Observatory Jena since begin of 2006. This article describes the main characteristics of the new camera. The properties of the CCD detector, the CTK image quality, as well as its detection limits for all filters are presented. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  20. [Critical mass, explosive participation at the Max-Planck Institute about research of the living conditions of the scientific-technical world in Starnberg].

    PubMed

    Sonntag, Philipp

    2014-01-01

    Reviewers of the Max-Planck-Institut zur Erforschung der Lebensbedingungen der wissenschaftlich-technischen Welt (MPIL) did focus upon an abundance of vague reports of evaluative commissions, of benchmarking, of scientific modes. Thus it remained rather neglected, what staff actually had researched. An example: Progression and end of project AKR (Work-Consumption-Assessment) does display all kinds of related emotions at MPIL, and the sensitive guidance by Carl Friedrich von Weizsäcker.

  1. The Magnetic Observatory Buildings at the Royal Observatory, Cape

    NASA Astrophysics Data System (ADS)

    Glass, I. S.

    2015-10-01

    During the 1830s there arose a strong international movement, promoted by Carl Friedrich Gauss and Alexander von Humboldt, to characterise the earth's magnetic field. By 1839 the Royal Society in London, driven by Edward Sabine, had organised a "Magnetic Crusade" - the establishment of a series of magnetic and meteorological observatories around the British Empire, including New Zealand, Australia, St Helena and the Cape. This article outlines the history of the latter installation, its buildings and what became of them.

  2. [Christian Andreas Cothenius (1708-1789). A pro-memoria on the occasion of the 200th anniversary of his death].

    PubMed

    Völker, A

    1990-04-01

    The 200th anniversary of the death of Christian Andreas Cothenius gave occasion to appreciate life and work of this personage of a physician. Cothenius maintained manifold connections to Halle, of which the golden doctorate and the heritage of the pharmaceutic enterprises of his teacher Friedrich Hoffmann were treated in this place. The picture of the local relations was supplemented by the history of the Cothenius medal which is today awarded by the Leopoldina of Halle.

  3. Multiphase flow modeling based on the hyperbolic thermodynamically compatible systems theory

    SciTech Connect

    Romenski, E.

    2015-03-10

    An application of the theory of thermodynamically compatible hyperbolic systems to design a multiphase compressible flow models is discussed. With the use of such approach the governing equations are derived from the first principles, formulated in a divergent form and can be transformed to a symmetric hyperbolic system in the sense of Friedrichs. A usage of the proposed approach is described for the development of multiphase compressible fluid models, including two-phase flow models.

  4. Furious Frederich: Nietzsche's neurosyphilis diagnosis and new hypotheses.

    PubMed

    André, Charles; Rios, André Rangel

    2015-12-01

    The causes of Friedrich Nietzsche's mental breakdown in early 1889 and of the subsequent slow decay to end-stage dementia along ten years will possibly remain open to debate. The diagnosis of syphilitic dementia paralytica, based only on medical anamnesis and physical examination, was considered indisputable by Otto Binswanger. On the other hand, taking into account recently described diseases, selectively collected evidence lend some support to alternative hypotheses: basal forebrain meningioma, CADASIL, MELAS and frontotemporal dementia.

  5. Spin-driven inflation

    NASA Astrophysics Data System (ADS)

    Obukhov, Yuri N.

    1993-11-01

    Following recent studies of Ford, we suggest - in the framework of general relativity - an inflationary cosmological model with self-interacting spinning matter. A generalization of the standard fluid model is discussed and estimates of the physical parameters of the evolution are given. I would like to thank Professor Friedrich W. Hehl for the careful reading of the manuscript and useful advice. This research was supported by the Alexander von Humboldt Foundation (Bonn).

  6. Furious Frederich: Nietzsche's neurosyphilis diagnosis and new hypotheses.

    PubMed

    André, Charles; Rios, André Rangel

    2015-12-01

    The causes of Friedrich Nietzsche's mental breakdown in early 1889 and of the subsequent slow decay to end-stage dementia along ten years will possibly remain open to debate. The diagnosis of syphilitic dementia paralytica, based only on medical anamnesis and physical examination, was considered indisputable by Otto Binswanger. On the other hand, taking into account recently described diseases, selectively collected evidence lend some support to alternative hypotheses: basal forebrain meningioma, CADASIL, MELAS and frontotemporal dementia. PMID:26465288

  7. The design of an improved endwall film-cooling configuration

    SciTech Connect

    Friedrichs, S.; Hodson, H.P.; Dawes, W.N.

    1999-10-01

    The endwall film-cooling cooling configuration investigated by Friedrichs et al. (1196, 1997) had in principle sufficient cooling flow for the endwall, but in practice, the redistribution of this coolant by secondary flows left large endwall areas uncooled. This paper describes the attempt to improve upon this datum cooling configuration by redistributing the available coolant to provide a better coolant coverage on the endwall surface, while keeping the associated aerodynamic losses small. The design of the new, improved cooling configuration was based on the understanding of endwall film-cooling described by Friedrichs et al. (1996, 1997). Computational fluid dynamics were used to predict the basic flow and pressure field without coolant ejection. Using this as a basis, the above-described understanding was used to place cooling holes so that they would provide the necessary cooling coverage at minimal aerodynamic penalty. The simple analytical modeling developed by Friedrichs et al. (1997) was then used to check that the coolant consumption and the increase in aerodynamic loss lay within the limits of the design goal. The improved cooling configuration was tested experimentally in a large-scale, low-speed linear cascade. An analysis of the results shows that the redesign of the cooling configuration has been successful in achieving an improved coolant coverage with lower aerodynamic losses, while using the same amount of coolant as in the datum cooling configuration. The improved cooling configuration has reconfirmed conclusions from Friedrichs et al. (1996, 1997): First, coolant ejection downstream of the three-dimensional separation lines on the endwall does not change the secondary flow structures: second, placement of holes in regions of high static pressure helps reduce the aerodynamic penalties of platform coolant ejection: finally, taking account of secondary flow can improve the design of endwall film-cooling configurations.

  8. Non linear effects in ferrite tuned cavities

    SciTech Connect

    Goren, Y.; Mahale, N.; Walling, L.; Enegren, T.; Hulsey, G. ); Yakoviev, V.; Petrov, V. )

    1993-05-01

    The phenomenon of dependence of the resonance shape and frequency on the RF power level in perpendicular biased ferrite-tuned cavities has been observed by G. Hulsey and C. Friedrichs in the SSC test cavity experiment. This paper presents a theoretical as well as numerical analysis of this phenomenon and compares the results with experimental data. The effect of this nonlinearity on the SSC low energy booster prototype cavity is discussed.

  9. [The history of medical physics and biophysics at the Humboldt University in Berlin].

    PubMed

    Schneck, P

    2001-01-01

    The present Institute of Medical Physics and Biophysics (former Institute of Radiation Research) was established on September 1st in 1923 by Walter Friedrich (1883-1968). It was after the Institute in Frankfurt A.M. (founded by Friedrich Dessauer in 1921) - the second Institute of its kind in Germany. As a physicist who wrote his dissertation under Wilhelm Conrad Röntgen, he did research together with a Gynecologist in Friedburg on problems of radiation therapy and the prevention of radiation injuries. Thus Friedrich became one of the first German Biomedical Physicists and was appointed to a professorship at the university of Berlin and its faculty of medicine. The paper gives a survey of the history of the Institute of Radiation Research in the twenties, in the time of Nazi-rule, the period after the World War II and in the era of GDR until 1990 and up to the present time. The succession of directorship of the Institute and the main research subjects in medical physics and biophysics have been sketched.

  10. Nonlinear stability of discrete shocks for systems of conservation laws

    NASA Astrophysics Data System (ADS)

    Liu, Jian-Guo; Xin, Zhouping

    1993-09-01

    In this paper we study the asymptotic nonlinear stability of discrete shocks for the Lax-Friedrichs scheme for approximating general m×m systems of nonlinear hyperbolic conservation laws. It is shown that weak single discrete shocks for such a scheme are nonlinearly stable in the L p-norm for all p ≧ 1, provided that the sums of the initial perturbations equal zero. These results should shed light on the convergence of the numerical solution constructed by the Lax-Friedrichs scheme for the single-shock solution of system of hyperbolic conservation laws. If the Riemann solution corresponding to the given far-field states is a superposition of m single shocks from each characteristic family, we show that the corresponding multiple discrete shocks are nonlinearly stable in L p (P ≧ 2). These results are proved by using both a weighted estimate and a characteristic energy method based on the internal structures of the discrete shocks and the essential monotonicity of the Lax-Friedrichs scheme.

  11. Low energy singly and multiply charged ion irradiation of astrophysical ices

    NASA Astrophysics Data System (ADS)

    Dawes, A.; Holtom, P. D.; Mukerji, R. J.; Davis, M. P.; Sivaraman, B.; McCullough, R. W.; Williams, I.; Mason, N. J.

    Ion induced processes play an important role in the chemical modification of astrophysical ices, both on the surfaces of satellites in the outer solar system and in the depths of dark molecular clouds where few photons penetrate. To date many laboratory studies have been developed to study energetic singly charged ion interactions with astrophysical ice analogues (e.g. Mennella, et al 2004; Strazzulla, Baratta & Palumbo 2001; Gerakines, Moore, & Hudson 2000) and have been found to produce new chemical species and cause significant effects on ice morphology (Palumbo 2005). However, the effects of low energy and multiply charged ions have not yet been investigated. Such ions are prevalent in many astrophysical environments: as primary and secondary particles generated by cosmic ray bombardment and as constituents of planetary magnetospheres (e.g. Jupiter and Saturn). These ions comprise a rich variety of reactive species in a variety of charge states with typical kinetic energies of few keV. The effect of slow, multiply charged ions (MCIs) with the surfaces of astrophysical ices and their possible effect on chemical processing is unclear. However, studies of MCI impacts with insulator surfaces suggest that they may play an important role due to surplus potential energy imparted at the surface of the target (Winter & Aumayr 2001). We have developed a research program to study ion interactions with astrophysical ices using an Electron Cyclotron Resonance (ECR) ion source at Queens University Belfast. Such a source can produce different species of ions with variable energy and different charge states. Ices are prepared in situ by depositing gas onto a cold infrared transmitting window. Samples are analysed using FTIR spectroscopy during irradiation. We have conducted a series of experiments to investigate the effects of ion charge state (potential vs. kinetic energy effects), ion energy (nuclear vs. electronic stopping processes) and sample temperature. In this poster

  12. Fire in the Sea

    NASA Astrophysics Data System (ADS)

    Friedrich, Walter L.

    2000-05-01

    The legend of the lost city of Atlantis has captivated the human imagination for centuries. Did this city actually exist, and, if so, what happened to it? Was it destroyed in the greatest cataclysmic event of the Bronze Age? While the truth behind the legend of Atlantis may never be known, Fire in the Sea tells the story of one of the largest and most devastating natural disasters of classical history that may also hold vital clues to the possible existence and fate of the lost city. In vivid prose, author Walter L. Friedrich describes the eruption of the Greek island of Santorini, or Thera, sometime in the 17th or 16th century BC. This eruption, perhaps one of the largest explosions ever witnessed by humankind, sent a giant cloud of volcanic ash into the air that eventually covered settlements on the island. Friedrich relates how this event forever altered the course of civilization in the region, and inspired a mystery that has fired humanity's imagination ever since. More than 160 elegant, full-color photographs and vivid prose capture the beauty, the geology, archaeology, history, peoples and environmental setting of Santorini. Fire in the Sea will readily appeal to the general reader interested in natural catastrophies as well as the beauty of the region. It will also enchant anyone who has ever dreamt about uncovering the mystery of the legend of Atlantis. Walter Friedrich is currently an associate professor at the Department of Earth Sciences, University of Aarhus, Denmark. He has visited Santorini at least 35 times since 1975 and has published numerous scientific articles in such international journals as Nature, Lethaia, Spektrum der Wissenschaft, and other publications.

  13. Some Historical Points of Interest in Göttingen

    NASA Astrophysics Data System (ADS)

    Hentschel, Klaus

    The Georgia Augusta University of Göttingen, founded in 1737, was a child of the Enlightenment, and the new sciences have always played a major role here.1 Among the teachers of physics, physical chemistry, astronomy, and related subjects we find Johann Christian Polykarp Erxleben, Georg Christoph Lichtenberg, Johann Tobias Mayer, Carl Friedrich Gauss, Johann B. Listing, Wilhelm Eduard Weber, Woldemar Voigt, Friedrich Kohlrausch, Eduard Riecke, Walther Nernst and Peter Debye — the last two subsequently moved on to Berlin. In the 1920s, physics students were jestingly referred to as “Frankierte, Bornierte und Polierte” (loosely translated as stamped, limited and polished), in allusion to their teachers, the theoretical physicist Max Born and the experimentalists James Franck and Robert Wichard Pohl, the first two being important figures in the history of quantum theory, the third, one of the founding fathers of experimental solid state physics.2 The National Socialist’s rise to power had a devastating effect on this world-renowned center for physics and mathematics. Most of its high-caliber scientists either were dismissed on the basis of the racist “Law for the Restoration of the Professional Civil Service” or themselves felt compelled to emigrate: About a dozen members of the physics faculty, including Born and Franck, and ten from the mathematics faculty left Göttingen.3 After the war, Richard Becker, who in 1936 had received a compulsory order to take the chair for theoretical physics vacant since Born’s emigration, and Friedrich Hund, who was also an enthusiastic historian of science, distinguished themselves as physics teachers there but the university as a whole never recovered its international standing of before 1933 (see Figs. 1 and 2).

  14. Late Pleistocene oscillations of the Drau Glacier (southern Austria)

    NASA Astrophysics Data System (ADS)

    Karnitschar, Christina; Reitner, Jürgen; Draganits, Erich

    2016-04-01

    The Drau Glacier was the largest Pleistocene glacier in the southeastern part of the Alps and significantly shaped the landscape in this region. The study area is located at the termination of the Drau Glacier in the southern part of Austria (Carinthia). The investigation aims to decipher glacial dynamics during the Late Pleistocene glacial advance, stabilisation and final recession of this glacier based on geological/geomorphological mapping, interpretation of airborne laser scan (ALS) topographic data and lithostratigraphic investigations of glacial and periglacial sediments. Special emphasis is laid on the reconstruction of the maximum extent of the glaciation (LGM). Based on previous mapping by Bobek (1959) and Ucik (1996-1998) more details have been gained for the paleogeographic reconstruction based on glacial and non-glacial erosion and accumulation features. These include traces of pre-Upper Pleistocene glaciation, drumlins, terminal moraines and kettle holes. Paleogeographic reconstruction was done with correlation of different outcrops based on lithostratigraphy and ALS topography. Sequences of gravel related to glacial advance covered by till, followed by periglacial sediments allowed detailed reconstruction of the glacial sequence in this area and the complex succession of various extents of the Drau Glacier. References Bobek, Hans. 1959: Der Eisrückgang im östlichen Klagenfurter Becken. In: Mitteilungen der österreichischen geographischen Gesellschaft, Wien. Ucik, Friedrich Hans. 1996: Bericht über geologische Aufnahmen im Quartär auf Blatt 204 Völkermarkt, Jb. Geol. B.-A., 141, S. 340, Wien. Ucik, Friedrich Hans. 1997: Bericht über geologische Aufnahmen im Quartär auf Blatt 204 Völkermarkt, Jb. Geol. B.-A., 141, S. 325-326, Wien. Ucik, Friedrich Hans. 1998: Bericht über geologische Aufnahmen im Quartär auf Blatt 204 Völkermarkt, Jb. Geol. B.-A., 142, S. 333-334, Wien.

  15. Variability of young stars: Determination of rotational periods of weak-line T Tauri stars in the Cepheus-Cassiopeia star-forming region

    NASA Astrophysics Data System (ADS)

    Koeltzsch, A.; Mugrauer, M.; Raetz, St.; Schmidt, T. O. B.; Roell, T.; Eisenbeiss, T.; Hohle, M. M.; Vaňko, M.; Ginski, Ch.; Marka, C.; Moualla, M.; Schreyer, K.; Broeg, Ch.; Neuhäuser, R.

    2009-05-01

    We report on observation and determination of rotational periods of ten weak-line T Tauri stars in the Cepheus-Cassiopeia star-forming region. Observations were carried out with the Cassegrain-Teleskop-Kamera (CTK) at University Observatory Jena between 2007 June and 2008 May. The periods obtained range between 0.49 d and 5.7 d, typical for weak-line and post T Tauri stars. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  16. CTK-II & RTK: The CCD-cameras operated at the auxiliary telescopes of the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.

    2016-03-01

    The Cassegrain-Teleskop-Kamera (CTK-II) and the Refraktor-Teleskop-Kamera (RTK) are two CCD-imagers which are operated at the 25 cm Cassegrain and 20 cm refractor auxiliary telescopes of the University Observatory Jena. This article describes the main characteristics of these instruments. The properties of the CCD-detectors, the astrometry, the image quality, and the detection limits of both CCD-cameras, as well as some results of ongoing observing projects, carried out with these instruments, are presented. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  17. STK: A new CCD camera at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.; Berthold, T.

    2010-04-01

    The Schmidt-Teleskop-Kamera (STK) is a new CCD-imager, which is operated since begin of 2009 at the University Observatory Jena. This article describes the main characteristics of the new camera. The properties of the STK detector, the astrometry and image quality of the STK, as well as its detection limits at the 0.9 m telescope of the University Observatory Jena are presented. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  18. Mineral resource of the month: cadmium

    USGS Publications Warehouse

    Tolcin, Amy C.

    2012-01-01

    The element cadmium was discovered in 1817 by Friedrich Stromeyer, a professor of chemistry at the University of Göttingen in Germany. Stromeyer noticed that a yellowish glow would occur when heat was applied to certain samples of calamine, a zinc-carbonate. This was unusual as the reaction was expected to be colorless. After further testing, Stromeyer deduced that an unknown metallic impurity in the carbonate caused the color change. He called the new metal "cadmium" after "kadmeia," the Greek word for calamine.

  19. [Poet-physicians in German literature].

    PubMed

    Perels, C

    1991-12-17

    Starting with standards arising from the relationship between medicine and art in classical antiquity, biblical tradition and teutonic-pagan antiquity, this article roams through german literature from the Middle Ages up to the 20th century, from Hildegard of Bingen to Gottfried Benn and Alfred Döblin, guided by the question, how strongly medical knowledge and medical practise are reflected in the poetry of writing physicians. Individual dispositions and epoque-specific features are discussed. Special attention is given to Paul Fleming and Angelus Silesius, Albrecht von Haller and Friedrich Schiller, romanticism and Georg Büchner. PMID:1754781

  20. LETTER TO THE EDITOR: The terminating of doubly excited 1,3Po resonances in H- below the n = 2 H threshold

    NASA Astrophysics Data System (ADS)

    Chen, Ming-Keh

    1999-09-01

    We examine the possibility of the resonances of an H- 1,3Po dipole series being formed below the n = 2 hydrogen threshold. Including the relativistic and QED corrections as first-order perturbations, the series will be terminated after the third resonance for 1Po symmetry and the fourth resonance for 3Po symmetry. The total angular momentum, J, is shown to be 0 for the fourth resonance of a 3Po series. This figure is in disagreement with that of Purr and Friedrich. The present resonant energies and widths were calculated by the saddle-point complex rotation method with B-spline functions.

  1. On conformal variational problems and free boundary continua

    NASA Astrophysics Data System (ADS)

    Marsland, Stephen; McLachlan, Robert I.; Modin, Klas; Perlmutter, Matthew

    2014-04-01

    We develop a framework for deriving governing partial differential equations for variational problems on spaces of conformal mappings. The main motivation is to obtain differential equations for the conformal motion of free boundary continua, of interest in image and shape registration. A fundamental tool in the paper, the Hodge-Morrey-Friedrichs decompositions of differential forms on manifolds with boundaries, is used to identify the orthogonal complement of the subspace of conformal mappings. A detailed presentation of these decompositions is included in the paper.

  2. 'Shooting at the sun god Apollo': the Apollonian-Dionysian balance of the TimeSlips Storytelling Project.

    PubMed

    George, Daniel R

    2013-09-01

    In The Birth of Tragedy, Friedrich Nietzsche celebrated the dueling forces of reason and emotion as personified by the ancient Greek gods Apollo and Dionysus. A subtle Apollonian-Dionysian balance can be observed in TimeSlips, a group-based creative storytelling activity developed in the 1990s and increasingly used in dementia care settings worldwide. This article explains how the Apollonion-Dionysian aspects of TimeSlips are beneficial not only for persons with dementia, but also for their carers. Narrative data from medical students at Penn State College of Medicine who participated in TimeSlips at a local retirement community are shared.

  3. 10. Photocopy of an engraving of a stained glass window ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photocopy of an engraving of a stained glass window design by Johann Friedrich Overbeck (1789-1869) on which two of the chancel windows in the Church of the Holy Cross are thought to have been based. This copy is of a photocopy obtained from the Treasury of Notre Dame de Paris, Paris, France, by the late Mrs. Walter C. White of Stateburg, South Carolina. Mrs. White's photocopy is in the possession of Mrs. Richard K. Anderson of the Borough House at Stateburg. - Church of the Holy Cross, State Route 261, Stateburg, Sumter County, SC

  4. Axes, planes and tubes, or the geometry of embryogenesis.

    PubMed

    Brauckmann, Sabine

    2011-12-01

    The paper presents selected figures of chick embryogenesis as depicted in the classic studies of Caspar Friedrich Wolff (1734-1794), Christian Heinrich Pander (1794-1865) and Karl Ernst von Baer (1792-1786). My main objective here is (1) to demonstrate how the imagery of Wolff, Pander and Baer attempted to project an image of a 3-dimensional rotating body into static figures on paper by means of linear contours, and (2) to ponder on the efficacy and pervasiveness of dots, lines and arrows for depicting embryogenesis. PMID:22035710

  5. Chladni Patterns on Drumheads: A ``Physics of Music'' Experiment

    NASA Astrophysics Data System (ADS)

    Worland, Randy

    2011-01-01

    In our "Physics of Music" class for non-science majors, we have developed a laboratory exercise in which students experiment with Chladni sand patterns on drumheads. Chladni patterns provide a kinesthetic, visual, and entertaining way to illustrate standing waves on flat surfaces and are very helpful when making the transition from one-dimensional systems, such as string and wind instruments, to the two-dimensional membranes and plates of the percussion family. Although the sand patterns attributed to Ernst Florens Friedrich Chladni (1756-1827) are often demonstrated for this purpose using metal plates,2-4 the use of drumheads offers several pedagogical and practical advantages in the lab.

  6. The discrete one-sided Lipschitz condition for convex scalar conservation laws

    NASA Technical Reports Server (NTRS)

    Brenier, Yann; Osher, Stanley

    1986-01-01

    Physical solutions to convex scalar conservation laws satisfy a one-sided Lipschitz condition (OSLC) that enforces both the entropy condition and their variation boundedness. Consistency with this condition is therefore desirable for a numerical scheme and was proved for both the Godunov and the Lax-Friedrichs scheme--also, in a weakened version, for the Roe scheme, all of them being only first order accurate. A new, fully second order scheme is introduced here, which is consistent with the OSLC. The modified equation is considered and shows interesting features. Another second order scheme is then considered and numerical results are discussed.

  7. ["Dr Breuer will care for him with utmost attention." A plan for Nietzsche's neuropathological treatment in Vienna].

    PubMed

    Müller-Buck, Renate

    2007-01-01

    This essay is about a plan for the treatment of Friedrich Nietzsche by Josef Breuer in the spring of 1878. The plan was developed by Siegfried Lipiner, a philosphy student from Galicia and an admirer of Nietzsche, who was acquainted with Breuer as well as with Freud. Lipiner was convinced that Nietzsche could be treated by the Viennese specialists and tried his best to arrange this. However all his endeavors were frustrated by the opposition of Nietzsche's advisors in Basel, as well as his docters, and ultimately of Nietzsche himself who preferred the cold-water therapy in Baden-Baden.

  8. Rotational and rotationless states of weakly bound molecules

    SciTech Connect

    Lemeshko, Mikhail; Friedrich, Bretislav

    2009-05-15

    By making use of the quantization rule of Raab and Friedrich [Phys. Rev. A 78, 022707 (2008)], we derive simple and accurate formulae for the number of rotational states supported by a weakly bound vibrational level of a diatomic molecule and the rotational constants of any such levels up to the threshold, and provide a criterion for determining whether a given weakly bound vibrational level is rotationless. The results depend solely on the long-range part of the molecular potential and are applicable to halo molecules.

  9. Fractional Feynman-Kac equation for non-brownian functionals.

    PubMed

    Turgeman, Lior; Carmi, Shai; Barkai, Eli

    2009-11-01

    We derive backward and forward fractional Feynman-Kac equations for the distribution of functionals of the path of a particle undergoing anomalous diffusion. Fractional substantial derivatives introduced by Friedrich and co-workers [Phys. Rev. Lett. 96, 230601 (2006)10.1103/PhysRevLett.96.230601] provide the correct fractional framework for the problem. For applications, we calculate the distribution of occupation times in half space and show how the statistics of anomalous functionals is related to weak ergodicity breaking.

  10. The Tortured History of Gauss's Law

    NASA Astrophysics Data System (ADS)

    Spencer, Ross

    2009-10-01

    American physics textbooks contain the following equation, which is called Gauss's law: E .d S = qenclosed ɛ0 It is odd, however, that biographies of Karl Friedrich Gauss (1777-1855) contain no mention of this law. A brief history of this important result will be presented in which it will be shown that what we call Gauss's law today was originally guessed at by Joseph Priestly (1733-1804) after he read a letter from Benjamin Franklin (1706-1790), then was derived, forgotten, and re-derived several times in two different contexts by many of the luminaries of physics in the eighteenth and nineteenth centuries.

  11. A composite scheme for gas dynamics in Lagrangian coordinates

    SciTech Connect

    Shashkov, M.; Wendroff, B.

    1999-04-10

    One cycle of a composite finite difference scheme is defined as several time steps of an oscillatory scheme such as Lax-Wendroff followed by one step of a diffusive scheme such as Lax-Friedrichs. The authors apply this idea to gas dynamics in Lagrangian coordinates. They show numerical results in two dimensions for Noh`s infinite strength shock problem and the Sedov blast wave problem, and for several one-dimensional problems including a Riemann problem with a contact discontinuity. For Noh`s problem the composite scheme produces a better result than that obtained with a more conventional Lagrangian code.

  12. Axes, planes and tubes, or the geometry of embryogenesis.

    PubMed

    Brauckmann, Sabine

    2011-12-01

    The paper presents selected figures of chick embryogenesis as depicted in the classic studies of Caspar Friedrich Wolff (1734-1794), Christian Heinrich Pander (1794-1865) and Karl Ernst von Baer (1792-1786). My main objective here is (1) to demonstrate how the imagery of Wolff, Pander and Baer attempted to project an image of a 3-dimensional rotating body into static figures on paper by means of linear contours, and (2) to ponder on the efficacy and pervasiveness of dots, lines and arrows for depicting embryogenesis.

  13. Dual Variational Principles for 3-D Navier-Stokes Equations

    NASA Astrophysics Data System (ADS)

    Liu, G. L.

    Just recently the exact variational principles (VP) of the full 3-D Navier-Stokes equations of viscous flow have been successfully established for the first time by the present author by means of a systematic reversed deduction method via the undetermined function. As a continuation and further development of that - a pair of new dual (reciprocal)VP is generated herein by means of the Friedrichs involutory transformation. These VP have the advantage over the previous ones that they possess apparent physical meaning of energy, providing a new rigorous theoretical basis for the finite element analysis of 3-D viscous flow.

  14. Ontogeny recapitulates phylogeny: comparative immunology in Germany.

    PubMed

    Cooper, E L; Bosch, T C

    2000-01-01

    The innate immune system is in the spot light of modern immunology. Whenever protists, invertebrates and vertebrates are threatened by pathogens, they rapidly activate highly effective antimicrobial defense reactions. Because this young field develops very dynamically, it is important to ask what we really know about the mechanisms governing the innate immune defense system. This was the topic of a recent meeting entitled 'The Evolution of the Immune System', held at the Friedrich Schiller University in Jena, Germany. Leading scientists in the field of innate immunity presented their latest data in a historical and friendly setting.

  15. 'Shooting at the sun god Apollo': the Apollonian-Dionysian balance of the TimeSlips Storytelling Project.

    PubMed

    George, Daniel R

    2013-09-01

    In The Birth of Tragedy, Friedrich Nietzsche celebrated the dueling forces of reason and emotion as personified by the ancient Greek gods Apollo and Dionysus. A subtle Apollonian-Dionysian balance can be observed in TimeSlips, a group-based creative storytelling activity developed in the 1990s and increasingly used in dementia care settings worldwide. This article explains how the Apollonion-Dionysian aspects of TimeSlips are beneficial not only for persons with dementia, but also for their carers. Narrative data from medical students at Penn State College of Medicine who participated in TimeSlips at a local retirement community are shared. PMID:23722245

  16. Analysis of 2-spar cantilever wings with special reference to torsion and load transference

    NASA Technical Reports Server (NTRS)

    Kuhn, Paul

    1936-01-01

    This report deals with the analysis of 2-spar cantilever wings in torsion, taking cognizance of the fact that the spars are not independent, but are interconnected by ribs and other structural members. The principles of interaction are briefly explained, showing that the mutual relief action occurring depends on the "pure torsional stiffness" of the wing cross section. Various practical methods of analysis are outlined. The "Friedrichs-Von Karman equations" are shown to require the least amount of labor. Numerical examples by the several methods of analysis are given and the agreement between the calculation and experiment is shown.

  17. A mixed system modeling two-directional pedestrian flows.

    PubMed

    Goatin, Paola; Mimault, Matthias

    2015-04-01

    In this article, we present a simplified model to describe the dynamics of two groups of pedestrians moving in opposite directions in a corridor. The model consists of a 2 x 2 system of conservation laws of mixed hyperbolic-elliptic type. We study the basic properties of the system to understand why and how bounded oscillations in numerical simulations arise. We show that Lax-Friedrichs scheme ensures the invariance of the domain and we investigate the existence of measure-valued solutions as limit of a subsequence of approximate solutions. PMID:25811441

  18. [Weizsäcker's concept of time from the current viewpoint].

    PubMed

    Kiefer, Claus

    2014-01-01

    Carl Friedrich von Weizsäcker's concept of time is deeply based on the asymmetry between past and future, which he considers as a fundamental aspect of Nature. I review these ideas and their philosophical back ground and confront them with a presentation of the concept of time in modern physics. I argue that the observed irreversibility of our world can be understood from fundamental laws which are invariant under time reversal. I conclude with an outlook on the expected theory of quantum gravity. PMID:24974601

  19. A critique of Bernstein's beyond objectivism and relativism: science, hermeneutics, and praxis.

    PubMed

    Matusitz, Jonathan; Kramer, Eric

    2011-06-01

    This analysis comments on Bernstein's lack of clear understanding of subjectivity, based on his book, Beyond Objectivism and Relativism: Science, Hermeneutics, and Praxis. Bernstein limits his interpretation of subjectivity to thinkers such as Gadamer and Habermas. The authors analyze the ideas of classic scholars such as Edmund Husserl and Friedrich Nietzsche. Husserl put forward his notion of transcendental subjectivity and phenomenological ramifications of the relationship between subjectivity and objectivity. Nietzsche referred to subjectivity as "perspectivism," the inescapable fact that any and all consciousnesses exist in space and time. Consciousness is fundamentally constituted of cultural, linguistic, and historical dimensions.

  20. Historical Examples of Misrepresentation, Innovation, and Morality in Physical Science and Technology

    NASA Astrophysics Data System (ADS)

    Buchwald, Jed

    2016-03-01

    The pressures of publication, the desire to be first in innovation, and moral convictions have long been at work in the history of science and technology. Historians think and argue best through stories, so I've chosen three examples that exemplify one or more of these aspects. The first involves the discovery of electric waves by Heinrich Hertz in 1888; the second concerns the controlled production of electromagnetic radiation by Marconi and Fleming in the early 1900s; our final case involves a bitter controversy between the physicist Hermann von Helmholtz and the astronomer Friedrich Zöllner in the 1890s.

  1. Towards the Right Hamiltonian for Singular Perturbations via Regularization and Extension Theory

    NASA Astrophysics Data System (ADS)

    Neidhardt, Hagen; Zagrebnov, Valentin

    For singular potentials in quantum mechanics it can happen that the Schrödinger operator is not esssentially self-adjoint on a natural domain, i.e., each self-adjoint extension is a candidate for the right physical Hamiltonian. Traditional way to single out this Hamiltonian is the removing cut-offs for regularizing potential. Connecting regularization and extension theory we develop an abstract operator method to treat the problem of the right Hamiltonian. We show that, using the notion of the maximal (with respect to the perturbation) Friedrichs extension of unperturbed operator, one can classify the above problem as wellposed or ill-posed depending on intersection of the quadratic form domain of perturbation and deficiency subspace corresponding to restriction of unperturbed operator to stability domain. If this intersection is trivial, then the right Hamiltonian is unique: it coincides with the form sum of perturbation and the Friedrich extension of the unperturbed operator restricted to the stability domain. Otherwise it is not unique: the family of “right Hamiltonians” can be described in terms of symmetric extensions reducing the ill-posed problem to the well-posed problem.

  2. Digital learning programs - competition for the classical microscope?

    PubMed

    Schmidt, Peter

    2013-01-01

    The development of digital media has been impressive in recent years which is also among the reason for their increasing use in academic teaching. This is especially true for teaching Anatomy and Histology in the first two years in medical and dental curricula. Modern digital technologies allow for efficient, affordable and easily accessible distribution of histological images in high quality. Microscopy depends almost exclusively on such images. Since 20 years numerous digital teaching systems have been developed for this purpose. Respective developments have changed the ways students acquire knowledge and prepare for exams. Teaching staff should adapt lectures, seminars and labs accordingly. As a first step, a collection of high resolution digital microscopic slides was made available for students at the Friedrich-Schiller-University in Jena. The aim of the present study was to evaluate the importance of conventional light microscopy and related technologies in current and future medical and dental education aswell. A survey was done among 172 medical and dental students at the Friedrich-Schiller-University Jena. 51% of students use now frequently new digital media for learning histology in contrast to 5% in the year 2000 [1]. Digital media including Internet, CD- based learning combined with social networks successfully compete with classical light microscopy.

  3. Analysis and algorithms for a regularized Cauchy problem arising from a non-linear elliptic PDE for seismic velocity estimation

    SciTech Connect

    Cameron, M.K.; Fomel, S.B.; Sethian, J.A.

    2009-01-01

    In the present work we derive and study a nonlinear elliptic PDE coming from the problem of estimation of sound speed inside the Earth. The physical setting of the PDE allows us to pose only a Cauchy problem, and hence is ill-posed. However we are still able to solve it numerically on a long enough time interval to be of practical use. We used two approaches. The first approach is a finite difference time-marching numerical scheme inspired by the Lax-Friedrichs method. The key features of this scheme is the Lax-Friedrichs averaging and the wide stencil in space. The second approach is a spectral Chebyshev method with truncated series. We show that our schemes work because of (1) the special input corresponding to a positive finite seismic velocity, (2) special initial conditions corresponding to the image rays, (3) the fact that our finite-difference scheme contains small error terms which damp the high harmonics; truncation of the Chebyshev series, and (4) the need to compute the solution only for a short interval of time. We test our numerical scheme on a collection of analytic examples and demonstrate a dramatic improvement in accuracy in the estimation of the sound speed inside the Earth in comparison with the conventional Dix inversion. Our test on the Marmousi example confirms the effectiveness of the proposed approach.

  4. Zeit im Wandel der Zeit.

    NASA Astrophysics Data System (ADS)

    Aichelburg, P. C.

    Contents: Einleitung(P. C. Aichelburg). 1. Über Zeit, Bewegung und Veränderung (Aristoteles). 2. Ewigkeit und Zeit (Plotin). 3. Was ist die Zeit? (Augustinus). 4. Von der Zeit (Immanuel Kant). 5. Newtons Ansichten über Zeit, Raum und Bewegung (Ernst Mach). 6. Über die mechanische Erklärung irreversibler Vorgänge (Ludwig Boltzmann). 7. Das Maß der Zeit (Henri Poincaré). 8. Dauer und Intuition (Henri Bergson). 9. Die Geschichte des Unendlichkeitsproblems (Bertrand Russell). 10. Raum und Zeit (Hermann Minkowski). 11. Der Unterschied von Zeit und Raum (Hans Reichenbach). 12. Newtonscher und Bergsonscher Zeitbegriff (Norbert Wiener). 13. Die Bildung des Zeitbegriffs beim Kinde (JeanPiaget).14. Eine Bemerkung über die Beziehungen zwischen Relativitätstheorie und der idealistischen Philosophie (Kurt Gödel). 15. Der zweite Hauptsatz und der Unterschied von Vergangenheit und Zukunft (Carl Friedrich v. Weizsäcker). 16. Zeit als physikalischer Begriff (Friedrich Hund). 17. Zeitmessung und Zeitbegriff in der Astronomie (Otto Heckmann). 18. Kann die Zeit rückwärts gehen? (Martin Gardner). 19. Zeit und Zeiten (Ilya Prigogine, Isabelle Stengers). 20. Zeit als dynamische Größe in der Relativitätstheorie (P. C. Aichelburg).

  5. [The Helvetius dynasty].

    PubMed

    Van Heiningen, Teunis Willem

    2014-01-01

    The Helvetius dynasty originates from the Principality of Anhalt, in Germany. George Vigelius, one of its ancestors, was born in the Palatinate (Germany) and studied theology in the town of Basel (Switzerland), after which he was given the surname Swietser. In 1649, his eldest son, Johann Friedrich Swietser, moved to the United Provinces and changed his name into Johan Frederik Helvétius. In 1656, he took his doctorate of medicine at the university of Harderwyck Guelderland). He settled in Amsterdam and moved later to The Hague, where he had a lightning career. Three of his four sons studied medicine in Leyden: Jean-Balthasar, Philippe-Maximilien, and Joseph-Jean. Jean-Adrien, the second son of Johann-Friedrich, settled in Paris and took his doctorate of medicine at the university of Reims, using the pseudonym of Christian-Lebrecht Helvétius. He had a prosperous career. He was the father of Jean-Claude-Adrien Helvétius, who became also a successful physician and first physician to the queen of France. His grandson was Claude-Adrien Helvétius, who became a leading philosopher and writer. PMID:25962212

  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.

  7. [150 years of the "Handbook of Plastic Surgery"--in memory of Eduard Zeis (1807-1868)].

    PubMed

    Sebastian, G

    1989-01-01

    Even before Joseph Lister (1827-1912) discovered and adopted the concept of antisepsis in 1867, pioneering work in the field of plastic surgery had already begun in Germany very early in the nineteenth century. The best known surgeons working in this field at that time were Karl Ferdinand von Graefe (1787-1840) and Johann Friedrich Dieffenbach (1794-1847) in Berlin and Philipp Franz von Walther (1782-1849) in Bonn and Munich. Three early plastic surgeons who were active in Dresden can and should be compared to them. These are, in chronological order, Johann August Wilhelm Hedenus (the elder; 1760-1834), Friedrich August von Ammon (1799-1861) and Eduard Zeis (1807-1868); Zeis' career is reviewed briefly here with the accent on Dresden. Born in Dresden on 1 October 1807, after finishing his training in 1932 he set up in general practice in his home town. Here he wrote his epoch-making "Handbuch der plastischen Chirurgie" (Handbook of Plastic Surgery; published in 1838), thus establishing the term "plastische Chirurgie", which has been adopted and assimilated into different languages all over the world. The best wishes of his friends went with him when Zeis went to take up the professorship in Marburg. This position did not live up to his expectations, however. In 1849 he returned to Dresden, where he worked until his death as senior medical officer in the newly established municipal hospital in Dresden-Friedrichstadt.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Karl Knorre - First Astronomer of the Nicolaev Observatory

    NASA Astrophysics Data System (ADS)

    Petrov, G.; Pinigin, G.

    Karl Friedrich Knorre was born 28th March 1801 in family of the professor of astronomy of Dorpat university Ernst Knorre. During education in the Dorpat university he got acquantance with the future director of Pulkovo observatory Wilhelm Struve. According passion of K. Knorre for astronomy W. Struwe recommended him to the director position of planned naval observatory in Nikolaev. From the foundation of Nikolaev naval and later astronomical observatory in 1821 K. Knorre was a first director. He made star position observations with the meridian circle, worked as a teacher of astronomy for sea navigators, compiled the fifth page of star map of the Berlin Academy of sciences and headed by all hydrographic determinations on the sea of Asov and Black sea. After 50 years K. Knorre retired 1871 from the Directorship of the Nikolaev observatory and moved to Berlin. Nikolaev astronomical observatory arranges the international scientific conference devoted to the 180 anniversary of NAO and 200's birthday of Karl Friedrich Knorre in 2001.

  9. Discontinuous Galerkin Method with Numerical Roe Flux for Spherical Shallow Water Equations

    NASA Astrophysics Data System (ADS)

    Yi, T.; Choi, S.; Kang, S.

    2013-12-01

    In developing the dynamic core of a numerical weather prediction model with discontinuous Galerkin method, a numerical flux at the boundaries of grid elements plays a vital role since it preserves the local conservation properties and has a significant impact on the accuracy and stability of numerical solutions. Due to these reasons, we developed the numerical Roe flux based on an approximate Riemann problem for spherical shallow water equations in Cartesian coordinates [1] to find out its stability and accuracy. In order to compare the performance with its counterpart flux, we used the Lax-Friedrichs flux, which has been used in many dynamic cores such as NUMA [1], CAM-DG [2] and MCore [3] because of its simplicity. The Lax-Friedrichs flux is implemented by a flux difference between left and right states plus the maximum characteristic wave speed across the boundaries of elements. It has been shown that the Lax-Friedrichs flux with the finite volume method is more dissipative and unstable than other numerical fluxes such as HLLC, AUSM+ and Roe. The Roe flux implemented in this study is based on the decomposition of flux difference over the element boundaries where the nonlinear equations are linearized. It is rarely used in dynamic cores due to its complexity and thus computational expensiveness. To compare the stability and accuracy of the Roe flux with the Lax-Friedrichs, two- and three-dimensional test cases are performed on a plane and cubed-sphere, respectively, with various numbers of element and polynomial order. For the two-dimensional case, the Gaussian bell is simulated on the plane with two different numbers of elements at the fixed polynomial orders. In three-dimensional cases on the cubed-sphere, we performed the test cases of a zonal flow over an isolated mountain and a Rossby-Haurwitz wave, of which initial conditions are the same as those of Williamson [4]. This study presented that the Roe flux with the discontinuous Galerkin method is less

  10. Causes and consequences of hypoxia on the Western Black Sea Shelf

    NASA Astrophysics Data System (ADS)

    Friedrich, Jana; Gomoiu, Marian-Trajan; Naeher, Sebastian; Secrieru, Dan; Teaca, Adrian

    2013-04-01

    The Black Sea, containing the world's largest natural anoxic basin since ca 7500 years (Jones & Gagnon 1994), suffers from combined effects of anthropogenic eutrophication, overfishing and climate variability (Oguz & Gilbert 2007). We discuss causes for hypoxia in western shelf waters. Freshwater runoff by the large rivers Danube, Dniester and Dnieper results in strong thermohaline stratification that limits bottom water ventilation on the north-western shelf during warm seasons. This makes the western shelf generally prone to oxygen deficiency. During autumn and winter, the thermohaline stratification is eroded by frequent storms and the water column is re-oxygenated. The causal chain of anthropogenic eutrophication since the 1970s led to seasonal hypoxia on the western shelf for more than 20 years causing the catastrophic decline of key shelf habitats (Mee et al. 2005). More frequent and intense algal blooms, red tides (i.e. Noctiluca, Prorocentrum cordatum) and changes in species composition in phytoplankton resulted in deposition of surplus organic matter on the seafloor increasing the oxygen demand, with serious consequences for pelagic and benthic ecosystem structure and functioning. During hypoxia, release of reduced substances like ammonia and phosphate from the sediment to the water fuelled eutrophication internally (Friedrich et al. 2002). The combination of existing data with those gained during EU FP7 HYPOX on the Romanian shelf enables to assess the development of bottom water hypoxia and changes in benthic community and hence, the current state and trends in recovery of the Romanian Black Sea shelf ecosystem. Mud worms are the winners of eutrophication and hypoxia, whereas filter feeders like Mytilus galloprovincialis and Acanthocardia paucicostata are the losers. The western shelf benthic ecosystem showed a significant reduction in species diversity, a reduction of biofilter strength due to the loss of filter-feeder populations and flourishing of

  11. [Intraocular Inflammation: Autoimmune or Infectious?].

    PubMed

    Auw-Hädrich, C; Heinzelmann, S; Coupland, S

    2016-07-01

    Presentation of 3 cases of intraocular inflammation: 1. 47-year old female patient with severe necrotising scleritis and uveitis with underlying granulomatous polyangiitis (formerly known as Wegener granulomatosis, in honour of the German pathologist Friedrich Wegener), known for 10 years. 2. 48-year old male patient with longstanding bilateral uveitis and granulomatous polyangiitis for 2 years. In the histopathological examination of the enucleation specimen, a retrolental tumour turned out to be a granuloma. 3. 57-year old male patient in status post renal transplantation with intraocular cellular infiltration suspicious for lymphoma, which surprisingly proved to be Toxoplasma gondii-associated uveitis. The clinical course and characteristic histological signs and therapeutic options are discussed. PMID:27468098

  12. Follow-up observations of Comet 17P/Holmes after its extreme outburst in brightness end of October 2007

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.; Hohle, M. M.; Ginski, C.; Vanko, M.; Freistetter, F.

    2009-05-01

    We present follow-up observations of comet 17/P Holmes after its extreme outburst in brightness, which occurred end of October 2007. We obtained 58 V-band images of the comet between October 2007 and February 2008, using the Cassegrain-Teleskop-Kamera (CTK) at the University Observatory Jena. We present precise astrometry of the comet, which yields its most recent Keplerian orbital elements. Furthermore, we show that the comet's coma expands quite linearly with a velocity of about 1650 km/s between October and December 2007. The photometric monitoring of comet 17/P Holmes shows that its photometric activity level decreased by about 5.9 mag within 105 days after its outburst. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  13. The Swelling of Olympic Gels

    NASA Astrophysics Data System (ADS)

    Lang, Michael; Fischer, Jakob; Werner, Marco; Sommer, Jens-Uwe

    2014-03-01

    The swelling equilibrium of Olympic gels is studied by Monte Carlo Simulations. We observe that gels consisting of flexible cyclic molecules of a higher degree of polymerization N show a smaller equilibrium swelling degree Q ~N - 0 . 28φ0- 0 . 72 for the same monomer volume fraction φ0 at network preparation. This observation is explained by a disinterpenetration process of overlapping non-concatenated polymers upon swelling. In the limit of a sufficiently large number of concatenations per cyclic molecule we expect that the equilibrium degree of swelling becomes proportional to φ0- 1 / 2 independent of N. Our results challenge current textbook models for the equilibrium degree of swelling of entangled polymer networks. Now at: Bio Systems Analysis Group, Jena Centre for Bioinformatics (JCB) and Department for Mathematics and Computer Sciences, Friedrich Schiller University of Jena, 07743 Jena, Germany.

  14. Photometric study of the OB star clusters NGC 1502 and NGC 2169 and mass estimation of their members at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Hohle, M. M.; Eisenbeiss, T.; Mugrauer, M.; Freistetter, F.; Moualla, M.; Neuhäuser, R.; Raetz, St.; Schmidt, T. O. B.; Tetzlaff, N.; Vaňko, M.

    2009-05-01

    In this work we present detailed photometric results of the trapezium like galactic nearby OB clusters NGC 1502 and NGC 2169 carried out at the University Observatory Jena. We determined absolute BV RI magnitudes of the mostly resolved components using Landolt standard stars. This multi colour photometry enables us to estimate spectral type and absorption as well as the masses of the components, which were not available for most of the cluster members in the literature so far, using models of stellar evolution. Furthermore, we investigated the optical spectrum of the components ADS 2984A and SZ Cam of the sextuple system in NGC 1502. Our spectra clearly confirm the multiplicity of these components, which is the first investigation of this kind at the University Observatory Jena. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  15. Photometric analysis of the eclipsing binary 2MASS 19090585+4911585

    NASA Astrophysics Data System (ADS)

    Raetz, St.; Vaňko, M.; Mugrauer, M.; Schmidt, T. O. B.; Roell, T.; Eisenbeiss, T.; Hohle, M. M.; Koeltzsch, A.; Ginski, Ch.; Marka, C.; Moualla, M.; Tetzlaff, N.; Broeg, Ch.; Neuhäuser, R.

    2009-05-01

    We report on observations of the eclipsing binary 2MASS 19090585+4911585 with the 25 cm auxiliary telescope of the University Observatory Jena. We show that a nearby brighter star (2MASS 19090783+4912085) was previously misclassified as the eclipsing binary and find 2MASS 19090585+4911585 to be the true source of variation. We present photometric analysis of V RI light curves. The system is an overcontact binary of W UMa type with an orbital period of (0.288374 ± 0.000010) d. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University Jena.

  16. 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

  17. Optimal time step for incompressible SPH

    NASA Astrophysics Data System (ADS)

    Violeau, Damien; Leroy, Agnès

    2015-05-01

    A classical incompressible algorithm for Smoothed Particle Hydrodynamics (ISPH) is analyzed in terms of critical time step for numerical stability. For this purpose, a theoretical linear stability analysis is conducted for unbounded homogeneous flows, leading to an analytical formula for the maximum CFL (Courant-Friedrichs-Lewy) number as a function of the Fourier number. This gives the maximum time step as a function of the fluid viscosity, the flow velocity scale and the SPH discretization size (kernel standard deviation). Importantly, the maximum CFL number at large Reynolds number appears twice smaller than with the traditional Weakly Compressible (WCSPH) approach. As a consequence, the optimal time step for ISPH is only five times larger than with WCSPH. The theory agrees very well with numerical data for two usual kernels in a 2-D periodic flow. On the other hand, numerical experiments in a plane Poiseuille flow show that the theory overestimates the maximum allowed time step for small Reynolds numbers.

  18. Child sexual behavior inventory: a comparison between Latino and normative samples of preschoolers.

    PubMed

    Kenny, Maureen C; Wurtele, Sandy K

    2013-01-01

    There is a relative dearth of research examining normative sexual behavior in Latino preschool children, despite an increased presence of Latinos as a minority population in the United States. To meet this need, a sample of Latino mothers were asked to complete the Child Sexual Behavior Inventory (CSBI; Friedrich et al., 1992 ) on their preschool-aged children (3 to 5 years old; n = 188). When their children's scores were compared to CSBI normative data, significant differences emerged. Compared to the normative sample, Latino boys and girls scored significantly higher on the sexual abuse specific items subscale, and Latino girls scored significantly higher on the developmentally related sexual behavior subscale. Possible cultural explanations for these elevations are explored.

  19. [Stahl, Leibniz, Hoffmann and breathing].

    PubMed

    Carvallo, Sarah

    2006-01-01

    At the beginning of the XVIII th century, Wilhelm Gottfried Leibniz and Friedrich Hoffmann criticize Georg Ernst Stahl's medical theory. They differenciate between unsound and true reasonings. Namely, they validate Stahl's definition of breath but extracting it from its animist basis and placing it in an epistemology obeying to the principle of sufficient reason and to the mechanical model. The stahlian discovery consists in understanding breath as a calorific ventilation against the ancient conception; the iatromechanists recognize its accuracy, but they try then to transpose it to a mechanical model of ventilation. Using it in a different epistemological context implies that they analyze the idea of discovery "true" in its contents, but "wrong" in its hypothesis. It impels to examine the epistemology of medical knowledge, as science and therapeutics, and in its links with the other scientific theories. Thus, if Leibniz as philosopher and Hoffmann as doctor consider Stahl's animism so important, it is because its discoveries question the fundamental principles of medicine.

  20. PHURBAS: AN ADAPTIVE, LAGRANGIAN, MESHLESS, MAGNETOHYDRODYNAMICS CODE. II. IMPLEMENTATION AND TESTS

    SciTech Connect

    McNally, Colin P.; Mac Low, Mordecai-Mark; Maron, Jason L. E-mail: jmaron@amnh.org

    2012-05-01

    We present an algorithm for simulating the equations of ideal magnetohydrodynamics and other systems of differential equations on an unstructured set of points represented by sample particles. The particles move with the fluid, so the time step is not limited by the Eulerian Courant-Friedrichs-Lewy condition. Full spatial adaptivity is required to ensure the particles fill the computational volume and gives the algorithm substantial flexibility and power. A target resolution is specified for each point in space, with particles being added and deleted as needed to meet this target. We have parallelized the code by adapting the framework provided by GADGET-2. A set of standard test problems, including 10{sup -6} amplitude linear magnetohydrodynamics waves, magnetized shock tubes, and Kelvin-Helmholtz instabilities is presented. Finally, we demonstrate good agreement with analytic predictions of linear growth rates for magnetorotational instability in a cylindrical geometry. This paper documents the Phurbas algorithm as implemented in Phurbas version 1.1.

  1. Woman astronomers in Berlin and Potsdam. (German Title: Astronominnen in Berlin und Potsdam)

    NASA Astrophysics Data System (ADS)

    Vogt, Annette

    This article examines the role of women astronomers in the region of Berlin-Potsdam. Were there any women astronomers? When and where were they employed? What were the training conditions for these women astronomers? And where can one find traces of their work? The article discusses the situation for women astronomers from the 18th century. It also offers an overview about all women who received their doctorates in astronomy, geophysics, and meteorology at the Berlin University (Friedrich-Wilhelms-Universitat zu Berlin) between 1899 and 1945. Finally, the article deals with the emergence of two patterns of women scientists. Both patterns are examples of different strategies used by women scientists to obtain positions in classical fields of male dominance and to illustrate the range of the reception of women scientists in the first half of the 20th century.

  2. 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.

  3. Hands of beauty, hands of horror: fear and Egyptian art at the Fin de Siècle.

    PubMed

    Briefel, Aviva

    2008-01-01

    This essay examines the gothicization of Egyptian manual productions in late-Victorian mummy narratives. These narratives often isolate the mummy's hand as a signifier of craftsmanship, a troubling object for a culture that was mourning the figurative loss of its artisans' hands to mechanized production. Focusing on Bram Stoker's 1903 novel, The Jewel of Seven Stars, I contend that the horror of the mummy's hand emanates from its ambiguous position as an artifact that is itself a means of production. It displaces Friedrich Engels's conception of the Western hand as a self-creating appendage into the atavistic domain of a long-lost Egyptian tradition, and in doing so, it forces the English observer to recognize the irrecoverable nature of aesthetic craftsmanship. Brought into violent contact with the creative potential of the mummy's hand, the characters in Stoker's novel try to disassociate the mummy from manual production but only succeed in confirming their own status as products of a mechanized age.

  4. Hilbert's axiomatic method and Carnap's general axiomatics.

    PubMed

    Stöltzner, Michael

    2015-10-01

    This paper compares the axiomatic method of David Hilbert and his school with Rudolf Carnap's general axiomatics that was developed in the late 1920s, and that influenced his understanding of logic of science throughout the 1930s, when his logical pluralism developed. The distinct perspectives become visible most clearly in how Richard Baldus, along the lines of Hilbert, and Carnap and Friedrich Bachmann analyzed the axiom system of Hilbert's Foundations of Geometry—the paradigmatic example for the axiomatization of science. Whereas Hilbert's axiomatic method started from a local analysis of individual axiom systems in which the foundations of mathematics as a whole entered only when establishing the system's consistency, Carnap and his Vienna Circle colleague Hans Hahn instead advocated a global analysis of axiom systems in general. A primary goal was to evade, or formalize ex post, mathematicians' 'material' talk about axiom systems for such talk was held to be error-prone and susceptible to metaphysics.

  5. A three-sphere swimmer for flagellar synchronization

    NASA Astrophysics Data System (ADS)

    Polotzek, Katja; Friedrich, Benjamin M.

    2013-04-01

    In a recent letter (Friedrich et al 2012 Phys. Rev. Lett. 109 138102), a minimal model swimmer has been proposed that propels itself at low Reynolds numbers by the revolving motion of a pair of spheres. The motion of the two spheres can synchronize by virtue of a hydrodynamic coupling that depends on the motion of the swimmer, but is rather independent of direct hydrodynamic interactions. This novel synchronization mechanism could account for the synchronization of a pair of flagella, e.g. in the green algae Chlamydomonas. In this paper, we discuss in detail how swimming and synchronization depend on the geometry of the model swimmer and compute the swimmer design for optimal synchronization. Our analysis highlights the role of broken symmetries in swimming and synchronization.

  6. A method for modeling oxygen diffusion in an agent-based model with application to host-pathogen infection

    SciTech Connect

    Plimpton, Steven J.; Sershen, Cheryl L.; May, Elebeoba E.

    2015-01-01

    This paper describes a method for incorporating a diffusion field modeling oxygen usage and dispersion in a multi-scale model of Mycobacterium tuberculosis (Mtb) infection mediated granuloma formation. We implemented this method over a floating-point field to model oxygen dynamics in host tissue during chronic phase response and Mtb persistence. The method avoids the requirement of satisfying the Courant-Friedrichs-Lewy (CFL) condition, which is necessary in implementing the explicit version of the finite-difference method, but imposes an impractical bound on the time step. Instead, diffusion is modeled by a matrix-based, steady state approximate solution to the diffusion equation. Moreover, presented in figure 1 is the evolution of the diffusion profiles of a containment granuloma over time.

  7. The Sargasso Sea Eel Expedition 1979

    NASA Astrophysics Data System (ADS)

    Tesch, F.-W.

    1982-09-01

    The background and aims of the Sargasso Sea Expedition for exploring the reproduction of the eel ( Anguilla spp.) in the North Atlantic are described. The ships used for the investigations in the Sargasso Sea and during transects across the North Atlantic were F. R. V. “Anton Dohrn” and R. V. “Friedrich Heincke”, provided by the Federal Republic of Germany. Their technical and scientific equipment and their staffs are described. The courses of the cruises are mapped and the geographical positions of the investigations as well as the different instruments employed are tabulated as a source of basic data for more specialized papers published in this issue or elsewhere. Reference is also given to relevant papers which have been published elsewhere. Important but unpublished preliminary results are mentioned. Suggestions for future research needs are made.

  8. A minimum entropy principle in the gas dynamics equations

    NASA Technical Reports Server (NTRS)

    Tadmor, E.

    1986-01-01

    Let u(x bar,t) be a weak solution of the Euler equations, governing the inviscid polytropic gas dynamics; in addition, u(x bar, t) is assumed to respect the usual entropy conditions connected with the conservative Euler equations. We show that such entropy solutions of the gas dynamics equations satisfy a minimum entropy principle, namely, that the spatial minimum of their specific entropy, (Ess inf s(u(x,t)))/x, is an increasing function of time. This principle equally applies to discrete approximations of the Euler equations such as the Godunov-type and Lax-Friedrichs schemes. Our derivation of this minimum principle makes use of the fact that there is a family of generalized entrophy functions connected with the conservative Euler equations.

  9. Three-dimensional analysis of heat flow, segregation, and interface shape of gradient-freeze crystal growth in a centrifuge

    NASA Astrophysics Data System (ADS)

    Lan, C. W.; Tu, C. Y.

    2001-06-01

    Three-dimensional (3D) heat flow, dopant segregation, and interface shape during crystal growth by a gradient freeze technique in a centrifuge are analyzed by a finite volume method. The basic flow patterns for a fixed geometry (with a concave interface) at different configurations agree well with the previous report (Friedrich et al., J. Crystal Growth 167 (1996) 45). However, the self-consistent analysis allows us for the first time to further investigate the role of the Coriolis force and centrifugal acceleration on the heat and mass transfer and the interface, simultaneously. Furthermore, the rotation speed found for the weakest convection, where the Coriolis force balances the gravitational and centrifugal forces, turns out to have larger radial segregation, despite having a larger effective segregation coefficient. Rotation about the growth axis is also investigated. For this configuration, it is found that both axial and radial segregation could be reduced under certain conditions.

  10. Baron Münchhausen and the syndrome which bears his name: history of an endearing personage and of a strange mental disorder.

    PubMed

    Olry, Régis

    2002-06-01

    Munchausen syndrome, a mental disorder, was named in 1951 by Richard Asher after Karl Friedrich Hieronymus, Baron Münchhausen (1720-1797), whose name had become proverbial as the narrator of false and ridiculously exaggerated exploits. The first edition of Münchhausen's tales appeared anonymously in 1785 (Baron Münchausen's narrative of his marvelous travels and campaigns in Russia), and was wrongly attributed to German poet Gottfried August Bürger who actually edited the first German version the following year. The real author, Rudolph Erich Raspe, never claimed his rights over the successive editions of this book. This paper reviews the extraordinary personality of Baron Münchhausen, and the circumstances which led Rudolph Erich Raspe, Gottfried August Bürger, and Richard Asher to pay homage to this very endearing personage.

  11. Historical and literary roots of Münchhausen syndromes: as intriguing as the syndromes themselves.

    PubMed

    Olry, Régis; Haines, Duane E

    2013-01-01

    Hieronymus Carl Friedrich Freiherr von Münchhausen (1720-1797) was a famous eighteenth-century teller of extravagant stories. In 1785, Rudolph Erich Raspe anonymously published the first book-form edition of Münchhausen's Tales, and a German translation was made available by Gottfried August Bürger the following year. Since that time, these adventures remained a best seller, and the name of the Baron was twice referred to in psychiatric terminology: "Münchhausen syndrome" coined by Richard Asher in 1951 and "Münchhausen syndrome by proxy" coined by Roy Meadow in 1977. This chapter examines the legitimacy of these terms in the light of historical and literary records and analyzes the synonyms or clinical types as found in medical publications. PMID:24290479

  12. "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.

  13. Pulmonary Alveolar Microlithiasis “Stone Lungs”: A Case of Clinico-Radiological Dissociation

    PubMed Central

    Shaharyar, Sameer; Chokshi, Binna; Bhardwaj, Nikhil

    2016-01-01

    Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by deposition of spherical calcium phosphate microliths called calcospherites within the alveoli. PAM was first described by Friedrich in 1856 and then by Harbitz in 1918. The disease pathogenesis is based on mutations in the SLC34A2 gene that encodes for the Type IIb sodium-phosphate cotransporter. The majority of the patients are diagnosed at an early age, usually between the ages of 20 and 40 years. The hallmark of this disease is a striking dissociation between the radiological findings and the mild clinical symptoms.  We report a case of 35-year-old woman who presented post-motor vehicle accident with back pain and with minimal dyspnea on exertion. The final diagnosis was made after computed tomography and lung biopsy. The present case exhibits the remarkable clinico-radiological dissociation with complete calcification of the lungs on radiographic images with a relatively mild clinical presentation.

  14. [Fatal diseases and "imaginary" suffering. "Hypochondria" and "consumption" in the correspondence between Jean Paul and Johann Bernhard Hermann, with a perspective on Jean Paul's literature and aesthetics].

    PubMed

    Meier, Monika

    2007-01-01

    The German writerJean Paul (Johann Paul Friedrich Richter, 1763-1825) and his friendJohann Bernhard Hermann (1761-1790) became acquainted with the thoughts of late Enlightenment at the University of Leipzig. They particularly appreciated the anthropology of Ernst Platner, who taught philosophy and aesthetics as well as medicine. Their confidential correspondence contains reflections on their respective situation and well being. Both write about feeling ill and label their illness "hypochondria". In the course of the correspondence Jean Paul's understanding of hypochondria evolves from an illness of the entrails as he follows Hermann, who supports the modern concept of hypochondria as an illness of the nerves. Two important themes from this correspondence recur in Jean Paul's novels and tales: firstly, his way of expressing comfort is related to his aesthetics, and secondly, the satirical way of portraying at least certain aspects of illness as imaginary reappears in his first successful novel "The Invisible Lodge" (1793).

  15. The composite finite volume method on unstructured meshes for the two-dimensional shallow water equations

    NASA Astrophysics Data System (ADS)

    Jiwen, Wang; Ruxun, Liu

    2001-12-01

    A composite finite volume method (FVM) is developed on unstructured triangular meshes and tested for the two-dimensional free-surface flow equations. The methodology is based on the theory of the remainder effect of finite difference schemes and the property that the numerical dissipation and dispersion of the schemes are compensated by each other in a composite scheme. The composite FVM is formed by global composition of several Lax-Wendroff-type steps followed by a diffusive Lax-Friedrich-type step, which filters out the oscillations around shocks typical for the Lax-Wendroff scheme. To test the efficiency and reliability of the present method, five typical problems of discontinuous solutions of two-dimensional shallow water are solved. The numerical results show that the proposed method, which needs no use of a limiter function, is easy to implement, is accurate, robust and is highly stable. Copyright

  16. A semi-Lagrangian approximation in the Navier-Stokes equations for the gas flow around a wedge

    NASA Astrophysics Data System (ADS)

    Shaydurov, V.; Liu, Tiegang; Shchepanovskaya, G.; Yakubovich, M.

    2015-10-01

    In the paper, a semi-Lagrangian approximation is presented for the numerical solution of the two-dimensional time-dependent Navier-Stokes equations for viscous heat-conducting gas. In each equation, a combination of three first-order derivatives describing the transfer of a corresponding substance (density, velocity components, or internal energy) along trajectories is interpreted as the "transfer derivative" in the transfer direction. The other terms of the equations are written in the Euler form. On the sought-for time level, the standard conforming finite element method is realized for them with the linear elements on triangles and the bilinear ones on rectangles. The stencil adaptation along trajectories enables us to avoid the Courant-Friedrichs-Lewy upper limit which describes the dependence of the time step on the mesh-size of the space triangulation. At the end of the paper, a numerical example illustrates the implementation of the described algorithms.

  17. The birth and development of the DNA theory of inheritance: sixty years since the discovery of the structure of DNA.

    PubMed

    Portin, Petter

    2014-04-01

    The development of the DNA theory of inheritance culminated in the publication of the molecular structure of DNA 60 years ago. This paper describes this development, beginning with the discovery of DNA as a chemical substance by Friedrich Miescher in 1869, followed by its basic chemical analysis and demonstration of its participation in the structure of chromosomes. Subsequently it was discovered by Oswald Avery in 1944 that DNA was the genetic material, and then Erwin Chargaff showed that the proportions of the bases included in the structure of DNA followed a certain law. These findings, in association with the biophysical studies of Maurice Wilkins and Rosalind Franklin with Raymond Gosling, led James Watson and Francis Crick to the discovery of the double-helical structure of DNA in 1953. The paper ends with a short description of the development of the DNA theory of inheritance after the discovery of the double helix.

  18. [DNA: from Miescher to Venter and beyond].

    PubMed

    Gabryelska, Marta M; Szymański, Maciej; Barciszewski, Jan

    2009-01-01

    DNA, one of the most famous molecules is 140-years-old. Its history has engaged three centuries of experiments, leading us to a point, where the Homo sapiens genome sequence is known. The "DNA breakthrough" is dated on 1953, when James Watson and Francis Crick proposed the model of molecular structure of DNA. But the origin of that great achievement goes back to 1869 and early efforts of Friedrich Miescher, the Swiss doctor, who isolated DNA (than termed nuclein) for the first time. Since that time wealth information on "nuclein", its functions, structure and usage has been collected and formed a basis for modern molecular biology, chemical biology and biotechnology. This article describes the events and circumstances of the most important DNA discoveries since its first isolation up to completing the human genome project and deep DNA sequencing techniques application.

  19. The Lenticular Process of the Incus

    PubMed Central

    Graboyes, Evan M.; Hullar, Timothy E.; Chole, Richard A.

    2011-01-01

    17th century anatomists, including Franciscus Sylvius, identified a small bony structure between the distal end of the incus and the stapes that they believed was a separate and thus additional ossicle. The existence of the ossicle at the distal portion of the long process of the incus was controversial for the next two hundred years. In the 19th century, anatomists including Johann Friedrich Blumenbach, Henry Jones Shrapnell, Eduard Hagenbach, and Joseph Hyrtl provided numerous arguments to demonstrate why the so-called additional ossicle was actually attached to the incus by a thin strut, and thus not a separate bone. Since then, the ovoid end of the incus has been referred to as the “lenticular process” of the incus. The best nomenclature for the bony connection between the lenticular process and the rest of the incus remains uncertain, but the term “lenticular process” should not include its connecting pedicle. PMID:21986927

  20. 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

  1. Solution of two-phase reacting flow in liquid thrust chambers

    NASA Astrophysics Data System (ADS)

    Dang, Anthony; Navaz, Homayun K.; Gross, Klaus W.

    1991-10-01

    A comprehensive Navier-Stokes code was developed for liquid rocket engine thrust chamber performance prediction. The code features multiple phases for liquid fuel and oxidizer droplets, group combustion effects, atomization models, full finite rate chemistry and the Chien low Reynolds number turbulence model. The multiple phase equations were cast in an Eulerian-Eulerian framework, which is essential for the treatment of dense spray. The discretization scheme is fully implicit and is based on the Lax-Friedrichs Total Variation Diminishing (TVD) scheme, which is accurate, very efficient and capable of handling steep gradients and stiff chemistry. The efficiency of the numerical scheme is essential for this application since the set of governing equations can be quite large (typically about forty in number). Preliminary results were obtained for the Space Shuttle Main Engine (SSME) and compared favorably with existing codes such as TDK and VIPER.

  2. [Occult medicine in the 20th century: pharmacotherapy by Demeter Georgievitz-Weitzer, known as Surya (1873 - 1949)].

    PubMed

    Helmstädter, Axel

    2011-01-01

    Demeter Georgievitz-Weitzer (1873-1949), called "Surya", Sanskrit for "sun", was an important representative of medical occultism in the first half of the 20th century. He worked as a journal editor and published a 13-volume book series about occult medicine, mainly written by himself. His hypotheses were closely related to the "Lebensreform" movement around 1900. Regarding diagnostics, he relied on astrology, cheiromancy, and clairvoyance, while therapeutics were dominated by diet and spagyric remedies according to Cesare Mattei (1809-1896) and Carl-Friedrich Zimpel (1801-1879). In his later years, he developed his own healing system, initially comprising eight, later only two preparations. Surya remedies were commercially available until the end of the 20th century,

  3. From the archives of scientific diplomacy: science and the shared interests of Samuel Hartlib's London and Frederick Clodius's Gottorf.

    PubMed

    Keller, Vera; Penman, Leigh T I

    2015-03-01

    Many historians have traced the accumulation of scientific archives via communication networks. Engines for communication in early modernity have included trade, the extrapolitical Republic of Letters, religious enthusiasm, and the centralization of large emerging information states. The communication between Samuel Hartlib, John Dury, Duke Friedrich III of Gottorf-Holstein, and his key agent in England, Frederick Clodius, points to a less obvious but no less important impetus--the international negotiations of smaller states. Smaller states shaped communication networks in an international (albeit politically and religiously slanted) direction. Their networks of negotiation contributed to the internationalization of emerging science through a political and religious concept of shared interest. While interest has been central to social studies of science, interest itself has not often been historicized within the history of science. This case study demonstrates the co-production of science and society by tracing how period concepts of interest made science international. PMID:26027306

  4. Zöllner's Universe

    NASA Astrophysics Data System (ADS)

    Kragh, Helge

    2012-12-01

    The idea that space is not Euclidean by necessity, and that there are other kinds of "curved" spaces, diffused slowly to the physical and astronomical sciences. Until Einstein's general theory of relativity, only a handful of astronomers contemplated a connection between non-Euclidean geometry and real space. One of them, the German astrophysicist Johann Carl Friedrich Zöllner (1834-1882), suggested in 1872 a remarkable cosmological model describing a finite universe in closed space. I examine Zöllner's little-known contribution to cosmology and also his even more unorthodox speculations of a four-dimensional space including both physical and spiritual phenomena. I provide an overview of Zöllner's scientific work, of his status in the German scientific community, and of the controversies caused by his polemical style of science. Zöllner's cosmology was effectively forgotten, but there is no reason why it should remain an unwritten chapter in the history of science.

  5. [The case of Sefeloge: a contribution to the history of forensic psychiatry].

    PubMed

    Haack, K; Herpertz, S C; Kumbier, E

    2007-05-01

    In 1850 the mentally disordered Sergeant Maximilian Joseph Sefeloge (1821-1859) tried to assassinate the Prussian King Friedrich Wilhelm IV (1795-1861). Besides clarification of the political background to the assassination, the question of the delinquent's criminal responsibility has been posed from the very beginning. For the first time Sefeloge's case is examined from a medicohistorical perspective. Due to the importance of the circumstances, a forensic scientist and three well-known psychiatrists made this forensic examination. These medical professionals seemed particularly competent because of their common experience with psychiatric patients. This unique case from nineteenth century Germany is exemplary in that the psychiatrist was generally accepted as an expert witness to evaluate crimes in the context of unclear mental conditions. From there the development of forensic psychiatry could proceed without hindrance.

  6. Scalar field probes of power-law space-time singularities

    NASA Astrophysics Data System (ADS)

    Blau, Matthias; Frank, Denis; Weiss, Sebastian

    2006-08-01

    We analyse the effective potential of the scalar wave equation near generic space-time singularities of power-law type (Szekeres-Iyer metrics) and show that the effective potential exhibits a universal and scale invariant leading inverse square behaviour ~ x-2 in the ``tortoise coordinate'' x provided that the metrics satisfy the strict Dominant Energy Condition (DEC). This result parallels that obtained in [1] for probes consisting of families of massless particles (null geodesic deviation, a.k.a. the Penrose Limit). The detailed properties of the scalar wave operator depend sensitively on the numerical coefficient of the x-2-term, and as one application we show that timelike singularities satisfying the DEC are quantum mechanically singular in the sense of the Horowitz-Marolf (essential self-adjointness) criterion. We also comment on some related issues like the near-singularity behaviour of the scalar fields permitted by the Friedrichs extension.

  7. 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.

  8. Freud's "bad conscience": The case of Nietzsche's Genealogy.

    PubMed

    Greer, Scott

    2002-01-01

    This article develops the argument that Friedrich Nietzsche influenced several aspects of Freud's later writings by illustrating, in particular, the impact of Nietzsche's On the Genealogy of Morals on Freud's Civilization and its Discontents. The theoretical and conceptual schemes represented in Freud's Discontents are found to bear a remarkable similarity to Nietzsche's Genealogy on a number of highly specific points. It is suggested that "DAS ES," "Uber-ich," and "bad conscience," concepts central to Freud's moral theory of mind, are at least partly derived from Nietzsche. Moreover, Freud's phylogenetic theory of guilt is based upon premises found in Nietzsche, as are specific details relating to ideas on human prehistory and the ancestral family. Based on this evidence, a re-examination of the moral and social dimensions of Freud's "structural" model may be in order.

  9. [The psychology of compassion. An analysis of the 100th anniversary of the death of Fredrich Nietzsche].

    PubMed

    Wilkes, J

    2000-06-01

    Friedrich Nietzsche is supposed to have been one of the harshest critics of compassion. Many of his publications try to unmask its failings and to expose its true motives. From an ardent admirer of Schopenhauers's ethics of compassion, Nietzsche turned into a vigorous despiser of compassionate feelings. It is shown that this change was above all caused by overwhelming personal experiences of compassion due to illness and death in his family and, later on, with his first aid activities in military hospitals during the German-French war in 1870. Combined with that, Nietzsche suffered from feelings of passivity and helplessness, which gave him the impression of compassion being a negative and--in the end--loathed emotion.

  10. Nietzsche, autobiography, history: mourning and Martin and John.

    PubMed

    Champagne, J

    1998-01-01

    How might gay and lesbian literature be read not as a mimetic representation of homosexuality, but as an activity linked to problems of subjectivity and historiography? Reading Dale Peck's novel Martin and John alongside passages from Friedrich Nietzsche's "On the Uses and Disadvantages of History for Life" and Sigmund Freud's "Mourning and Melancholia," this essay argues for an understanding of Peck's text as an attempt to link two apparently different processes of import to contemporary gay male subjects in particular: the writing of what Nietzsche terms "critical history," and the mourning of those lost to HIV disease. It concludes by linking Martin and John to feminist critiques of identity and traditional historiography, as well as noting the connection between these two critiques.

  11. Mitochondrial metals as a potential therapeutic target in neurodegeneration

    PubMed Central

    Grubman, A; White, A R; Liddell, J R

    2014-01-01

    Transition metals are critical for enzyme function and protein folding, but in excess can mediate neurotoxic oxidative processes. As mitochondria are particularly vulnerable to oxidative damage due to radicals generated during ATP production, mitochondrial biometal homeostasis must therefore be tightly controlled to safely harness the redox potential of metal enzyme cofactors. Dysregulation of metal functions is evident in numerous neurological disorders including Alzheimer's disease, stroke, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and Friedrich's ataxia. This review describes the mitochondrial metal defects in these disorders and highlights novel metal-based therapeutic approaches that target mitochondrial metal homeostasis in neurological disorders. Linked Articles This article is part of a themed issue on Mitochondrial Pharmacology: Energy, Injury & Beyond. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2014.171.issue-8 PMID:24206195

  12. Darwin, Engels und die Rolle der Arbeit in der biologischen und kulturellen Evolution des Menschen

    NASA Astrophysics Data System (ADS)

    Reichholf, Josef H.

    Im Jahre 1876, 5 Jahre nach Erscheinen von Darwins Buch über die Evolution des Menschen und die sexuelle Selektion (Darwin 1871), veröffentlichte Friedrich Engels den berühmt gewordenen Essay "Anteil der Arbeit an der Menschwerdung des Affen“ (Engels 1876). Die Kernfrage darin lautet in Kurzform: Warum hat der Mensch eigentlich ein Bedürfnis nach Arbeit? Engels Antwort wird nachfolgend näher betrachtet und vom gegenwärtigen Kenntnisstand aus beurteilt. Wie sich zeigen wird, beantworten seine Überlegungen die Frage nicht wirklich. Sie ist weiterhin offen. Es können lediglich einige zusätzliche Anhaltspunkte zur Diskussion gestellt werden. Angesichts des drängenden Problems millionenfacher Arbeitslosigkeit und der Forderungen nach einem "Grundrecht auf Arbeit“ kommt den Überlegungen zum möglichen Ursprung des Bedürfnisses nach Arbeit mehr als nur akademisches Interesse zu.

  13. The first measurement of the deflection of the vertical in longitude. The figure of the earth in the early 19th century

    NASA Astrophysics Data System (ADS)

    Schrimpf, Andreas

    2014-09-01

    During the summer of 1837 Christian Ludwig Gerling, a former student of Carl Friedrich Gauß's, organized the world wide first determination of the deflection of the vertical in longitude. From a mobile observatory at the Frauenberg near Marburg (Hesse) he measured the astronomical longitude difference between C.F. Gauß's observatory at Göttingen and F.G.B. Nicolai's observatory at Mannheim within an error of 0.̋4. To achieve this precision he first used a series of light signals for synchronizing the observatory clocks and, second, he very carefully corrected for the varying reaction time of the observers. By comparing these astronomical results with the geodetic-determined longitude differences he had recently measured for the triangulation of Kurhessen, he was able to extract a combined value of the deflection of the vertical in longitude of Göttingen and Mannheim. His results closely agree with modern vertical deflection data.

  14. A method for modeling oxygen diffusion in an agent-based model with application to host-pathogen infection

    DOE PAGES

    Plimpton, Steven J.; Sershen, Cheryl L.; May, Elebeoba E.

    2015-01-01

    This paper describes a method for incorporating a diffusion field modeling oxygen usage and dispersion in a multi-scale model of Mycobacterium tuberculosis (Mtb) infection mediated granuloma formation. We implemented this method over a floating-point field to model oxygen dynamics in host tissue during chronic phase response and Mtb persistence. The method avoids the requirement of satisfying the Courant-Friedrichs-Lewy (CFL) condition, which is necessary in implementing the explicit version of the finite-difference method, but imposes an impractical bound on the time step. Instead, diffusion is modeled by a matrix-based, steady state approximate solution to the diffusion equation. Moreover, presented in figuremore » 1 is the evolution of the diffusion profiles of a containment granuloma over time.« less

  15. Vectorization of the time-dependent Boltzmann transport equation: Application to deep penetration problems

    NASA Astrophysics Data System (ADS)

    Cobos, Agustín C.; Poma, Ana L.; Alvarez, Guillermo D.; Sanz, Darío E.

    2016-10-01

    We introduce an alternative method to calculate the steady state solution of the angular photon flux after a numerical evolution of the time-dependent Boltzmann transport equation (BTE). After a proper discretization the transport equation was converted into an ordinary system of differential equations that can be iterated as a weighted Richardson algorithm. As a different approach, in this work the time variable regulates the iteration process and convergence criteria is based on physical parameters. Positivity and convergence was assessed from first principles and a modified Courant-Friedrichs-Lewy condition was devised to guarantee convergence. The Penelope Monte Carlo method was used to test the convergence and accuracy of our approach for different phase space discretizations. Benchmarking was performed by calculation of total fluence and photon spectra in different one-dimensional geometries irradiated with 60Co and 6 MV photon beams and radiological applications were devised.

  16. Aerodynamic characteristics of a Sparrow 3 missile model in the flow field of a generalized parent body at Mach 2.86

    NASA Technical Reports Server (NTRS)

    Stallings, R. L., Jr.

    1984-01-01

    Longitudinal aerodynamic characteristics of a Sparrow 3 wing control missile model were measured through a range of separation distances relative to a flat plate surface that represented the parent-body configuration. Measurements were obtained with and without two dimensional circular arc protuberances attached to the flat plate surface. The tests were conducted at a Mach number of 2.86 and a Reynolds number per meter of 6.56 million. The behavior of these longitudinal characteristics with varying separation distance in the flow field created by the flat plate and protuberance was generally as would be expected on the basis of flow field boundaries determined from the second order approximation of Friedrich. In general, varying roll angle from 0 deg to 45 deg caused no significant effect on the store separation characteristics.

  17. Communications: When diffraction rules the stereodynamics of rotationally inelastic collisions

    NASA Astrophysics Data System (ADS)

    Lemeshko, Mikhail; Jambrina, Pablo G.; de Miranda, Marcelo P.; Friedrich, Bretislav

    2010-04-01

    Following upon our recent work on vector correlations in the Ar-NO collisions [Lemeshko and Friedrich, Phys. Chem. Chem. Phys. 12, 1038 (2010)], we compare model results with close-coupling calculations for a range of channels and collision energies for the He-NO system. The striking agreement between the model and exact polarization moments indicates that the stereodynamics of rotationally inelastic atom-molecule collisions at thermal energies is governed by diffraction of matter waves from a two-dimensional repulsive core of the atom-molecule potential. Furthermore, the model polarization moments characterizing the He-NO, He-O2, He-OH, and He-CaH stereodynamics are found to coalesce into a single, distinctive pattern, which can serve as a "fingerprint" to identify diffraction-driven stereodynamics in future work.

  18. From the archives of scientific diplomacy: science and the shared interests of Samuel Hartlib's London and Frederick Clodius's Gottorf.

    PubMed

    Keller, Vera; Penman, Leigh T I

    2015-03-01

    Many historians have traced the accumulation of scientific archives via communication networks. Engines for communication in early modernity have included trade, the extrapolitical Republic of Letters, religious enthusiasm, and the centralization of large emerging information states. The communication between Samuel Hartlib, John Dury, Duke Friedrich III of Gottorf-Holstein, and his key agent in England, Frederick Clodius, points to a less obvious but no less important impetus--the international negotiations of smaller states. Smaller states shaped communication networks in an international (albeit politically and religiously slanted) direction. Their networks of negotiation contributed to the internationalization of emerging science through a political and religious concept of shared interest. While interest has been central to social studies of science, interest itself has not often been historicized within the history of science. This case study demonstrates the co-production of science and society by tracing how period concepts of interest made science international.

  19. Hansteen's magnetometer and the origin of the magnetic crusade.

    PubMed

    Enebakk, Vidar

    2014-12-01

    In the early nineteenth century, Norwegian mathematician and astronomer Christopher Hansteen (1784-1873) contributed significantly to international collaboration in the study of terrestrial magnetism. In particular, Hansteen was influential in the origin and orientation of the magnetic lobby in Britain, a campaign which resulted in a global network of fixed geomagnetic observatories. In retrospect, however, his contribution was diminished, because his four-pole theory in Untersuchungen der Magnetismus der Erde (1819) was ultimately refuted by Carl Friedrich Gauss in Allgemeine Theorie des Erdmagnetismus (1839). Yet Hansteen's main contribution was practical rather than theoretical. His major impact was related to the circulation of his instruments and techniques. From the mid-1820s, 'Hansteen's magnetometer' was distributed all over the British Isles and throughout the international scientific community devoted to studying terrestrial magnetism. Thus in the decades before the magnetic crusade, Hansteen had established an international system of observation, standardization and representation based on measurements with his small and portable magnetometers. PMID:25546997

  20. Dual Rationality and Deliberative Agents

    NASA Astrophysics Data System (ADS)

    Debenham, John; Sierra, Carles

    Human agents deliberate using models based on reason for only a minute proportion of the decisions that they make. In stark contrast, the deliberation of artificial agents is heavily dominated by formal models based on reason such as game theory, decision theory and logic—despite that fact that formal reasoning will not necessarily lead to superior real-world decisions. Further the Nobel Laureate Friedrich Hayek warns us of the ‘fatal conceit’ in controlling deliberative systems using models based on reason as the particular model chosen will then shape the system’s future and either impede, or eventually destroy, the subtle evolutionary processes that are an integral part of human systems and institutions, and are crucial to their evolution and long-term survival. We describe an architecture for artificial agents that is founded on Hayek’s two rationalities and supports the two forms of deliberation used by mankind.

  1. 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.

  2. Three-dimensional efficient dispersive alternating-direction-implicit finite-difference time-domain algorithm using a quadratic complex rational function.

    PubMed

    Kim, E-K; Ha, S-G; Lee, J; Park, Y B; Jung, K-Y

    2015-01-26

    Efficient unconditionally stable FDTD method is developed for the electromagnetic analysis of dispersive media. Toward this purpose, a quadratic complex rational function (QCRF) dispersion model is applied to the alternating-direction-implicit finite-difference time-domain (ADI-FDTD) method. The 3-D update equations of QCRF-ADI-FDTD are derived using Maxwell's curl equations and the constitutive relation. The periodic boundary condition of QCRF-ADI-FDTD is discussed in detail. A 3-D numerical example shows that the time-step size can be increased by the proposed QCRF-ADI-FDTD beyond the Courant-Friedrich-Levy (CFL) number, without numerical instability. It is observed that, for refined computational cells, the computational time of QCRF-ADI-FDTD is reduced to 28.08 % of QCRF-FDTD, while the L2 relative error norm of a field distribution is 6.92 %.

  3. Nietzsche, autobiography, history: mourning and Martin and John.

    PubMed

    Champagne, J

    1998-01-01

    How might gay and lesbian literature be read not as a mimetic representation of homosexuality, but as an activity linked to problems of subjectivity and historiography? Reading Dale Peck's novel Martin and John alongside passages from Friedrich Nietzsche's "On the Uses and Disadvantages of History for Life" and Sigmund Freud's "Mourning and Melancholia," this essay argues for an understanding of Peck's text as an attempt to link two apparently different processes of import to contemporary gay male subjects in particular: the writing of what Nietzsche terms "critical history," and the mourning of those lost to HIV disease. It concludes by linking Martin and John to feminist critiques of identity and traditional historiography, as well as noting the connection between these two critiques. PMID:9505231

  4. Liquid-crystal science from 1888 to 1922: building a revolution.

    PubMed

    Mitov, Michel

    2014-05-19

    The saga of liquid crystals started with their discovery in 1888 by the botanist Friedrich Reinitzer, who unexpectedly observed "two melting points" for crystals extracted from the root of a carrot. At the end of the nineteenth century, most scientists did not believe in the existence of "liquid crystals" as promoted by the crystallographer Otto Lehmann. The controversies were very vivid; to the point that the recognition of mesomorphic states of matter by the scientific community required more than two decades. In the end, liquid crystals have changed our vision of matter by shattering the three-state paradigm. Since the mid-1970s, liquid crystals have revolutionized the worldwide information-display industry and now play a host of key roles in various technologies.

  5. Variational theorems for superimposed motions in elasticity, with application to beams

    NASA Technical Reports Server (NTRS)

    Doekmeci, M. C.

    1976-01-01

    Variational theorems are presented for a theory of small motions superimposed on large static deformations and governing equations for prestressed beams on the basis of 3-D theory of elastodynamics. First, the principle of virtual work is modified through Friedrichs's transformation so as to describe the initial stress problem of elastodynamics. Next, the modified principle together with a chosen displacement field is used to derive a set of 1-D macroscopic governing equations of prestressed beams. The resulting equations describe all the types of superimposed motions in elastic beams, and they include all the effects of transverse shear and normal strains, and the rotatory inertia. The instability of the governing equations is discussed briefly.

  6. A Posteriori Analysis for Hydrodynamic Simulations Using Adjoint Methodologies

    SciTech Connect

    Woodward, C S; Estep, D; Sandelin, J; Wang, H

    2009-02-26

    This report contains results of analysis done during an FY08 feasibility study investigating the use of adjoint methodologies for a posteriori error estimation for hydrodynamics simulations. We developed an approach to adjoint analysis for these systems through use of modified equations and viscosity solutions. Targeting first the 1D Burgers equation, we include a verification of the adjoint operator for the modified equation for the Lax-Friedrichs scheme, then derivations of an a posteriori error analysis for a finite difference scheme and a discontinuous Galerkin scheme applied to this problem. We include some numerical results showing the use of the error estimate. Lastly, we develop a computable a posteriori error estimate for the MAC scheme applied to stationary Navier-Stokes.

  7. Non-oscillatory central differencing for hyperbolic conservation laws

    NASA Technical Reports Server (NTRS)

    Nessyahu, Haim; Tadmor, Eitan

    1988-01-01

    Many of the recently developed high resolution schemes for hyperbolic conservation laws are based on upwind differencing. The building block for these schemes is the averaging of an appropriate Godunov solver; its time consuming part involves the field-by-field decomposition which is required in order to identify the direction of the wind. Instead, the use of the more robust Lax-Friedrichs (LxF) solver is proposed. The main advantage is simplicity: no Riemann problems are solved and hence field-by-field decompositions are avoided. The main disadvantage is the excessive numerical viscosity typical to the LxF solver. This is compensated for by using high-resolution MUSCL-type interpolants. Numerical experiments show that the quality of results obtained by such convenient central differencing is comparable with those of the upwind schemes.

  8. Hansteen's magnetometer and the origin of the magnetic crusade.

    PubMed

    Enebakk, Vidar

    2014-12-01

    In the early nineteenth century, Norwegian mathematician and astronomer Christopher Hansteen (1784-1873) contributed significantly to international collaboration in the study of terrestrial magnetism. In particular, Hansteen was influential in the origin and orientation of the magnetic lobby in Britain, a campaign which resulted in a global network of fixed geomagnetic observatories. In retrospect, however, his contribution was diminished, because his four-pole theory in Untersuchungen der Magnetismus der Erde (1819) was ultimately refuted by Carl Friedrich Gauss in Allgemeine Theorie des Erdmagnetismus (1839). Yet Hansteen's main contribution was practical rather than theoretical. His major impact was related to the circulation of his instruments and techniques. From the mid-1820s, 'Hansteen's magnetometer' was distributed all over the British Isles and throughout the international scientific community devoted to studying terrestrial magnetism. Thus in the decades before the magnetic crusade, Hansteen had established an international system of observation, standardization and representation based on measurements with his small and portable magnetometers.

  9. Reply to "Comment on `Self-assembly of magnetic balls: From chains to tubes' "

    NASA Astrophysics Data System (ADS)

    Messina, René; Stanković, Igor

    2015-05-01

    The authors of the Comment [Phys. Rev. E 91, 057201 (2015), 10.1103/PhysRevE.91.057201] propose compact round clusters as, energetically, better candidates than stacked rings found in Messina et al. [Phys. Rev. E 89, 011202 (2014), 10.1103/PhysRevE.89.011202] (forming open tubes) at a pretty large number of constitutive magnets, typically for N ≳1300 . Our new findings show that elongated rodlike structures can even outmatch the reported structures in Friedrich et al. [Phys. Rev. E 91, 057201 (2015), 10.1103/PhysRevE.91.057201] and in Messina et al. [Phys. Rev. E 89, 011202 (2014), 10.1103/PhysRevE.89.011202] from typically N ≳460 .

  10. Parallax: The Race to Measure the Cosmos

    NASA Astrophysics Data System (ADS)

    Hirshfeld, A. W.

    2001-05-01

    The new book "Parallax: The Race to Measure the Cosmos" chronicles the centuries-long struggle to secure the first distance to a star through detection of stellar parallax. Beginning with the naked-eye attempts of Tycho Brahe and proceeding through the telescopic studies of Robert Hooke, James Bradley, and William Herschel, all three of whom employed observational strategies suggested by Galileo, the effort to measure stellar parallax gained momentum in the early 19th century with dramatic improvements in telescope technology by German craftsmen such as Joseph Fraunhofer. Three near-contemporaneous announcements of stellar parallaxes were made in the late 1830s by Thomas Henderson (Alpha Centauri), Wilhelm Struve (Vega), and Friedrich Bessel (61 Cygni). By consensus of the astronomical community, Bessel was credited with the first successful measurement of a star's distance. With its biographical focus, "Parallax: The Race to Measure the Cosmos" highlights the human dimensions of scientific achievement.

  11. Non-oscillatory central differencing for hyperbolic conservation laws

    NASA Technical Reports Server (NTRS)

    Nessyahu, Haim; Tadmor, Eitan

    1990-01-01

    Many of the recently developed high resolution schemes for hyperbolic conservation laws are based on upwind differencing. The building block for these schemes is the averaging of an appropriate Godunov solver; its time consuming part involves the field-by-field decomposition which is required in order to identify the direction of the wind. Instead, the use of the more robust Lax-Friedrichs (LxF) solver is proposed. The main advantage is simplicity: no Riemann problems are solved and hence field-by-field decompositions are avoided. The main disadvantage is the excessive numerical viscosity typical to the LxF solver. This is compensated for by using high-resolution MUSCL-type interpolants. Numerical experiments show that the quality of results obtained by such convenient central differencing is comparable with those of the upwind schemes.

  12. On a fourth order accurate implicit finite difference scheme for hyperbolic conservation laws. I - Nonstiff strongly dynamic problems

    NASA Technical Reports Server (NTRS)

    Harten, A.; Tal-Ezer, H.

    1981-01-01

    An implicit finite difference method of fourth order accuracy in space and time is introduced for the numerical solution of one-dimensional systems of hyperbolic conservation laws. The basic form of the method is a two-level scheme which is unconditionally stable and nondissipative. The scheme uses only three mesh points at level t and three mesh points at level t + delta t. The dissipative version of the basic method given is conditionally stable under the CFL (Courant-Friedrichs-Lewy) condition. This version is particularly useful for the numerical solution of problems with strong but nonstiff dynamic features, where the CFL restriction is reasonable on accuracy grounds. Numerical results are provided to illustrate properties of the proposed method.

  13. [Occult medicine in the 20th century: pharmacotherapy by Demeter Georgievitz-Weitzer, known as Surya (1873 - 1949)].

    PubMed

    Helmstädter, Axel

    2011-01-01

    Demeter Georgievitz-Weitzer (1873-1949), called "Surya", Sanskrit for "sun", was an important representative of medical occultism in the first half of the 20th century. He worked as a journal editor and published a 13-volume book series about occult medicine, mainly written by himself. His hypotheses were closely related to the "Lebensreform" movement around 1900. Regarding diagnostics, he relied on astrology, cheiromancy, and clairvoyance, while therapeutics were dominated by diet and spagyric remedies according to Cesare Mattei (1809-1896) and Carl-Friedrich Zimpel (1801-1879). In his later years, he developed his own healing system, initially comprising eight, later only two preparations. Surya remedies were commercially available until the end of the 20th century, PMID:22822609

  14. A history of multiple sclerosis investigations in Canada between 1850 and 1950.

    PubMed

    Ganesh, Aravind; Stahnisch, Frank W

    2014-05-01

    The medical profession's modern quandaries with Multiple Sclerosis (MS) largely began in 1849, with Friedrich von Frerichs' (1819-1885) early description of the clinical and pathological features of what he termed Hirnsklerose ("brain sclerosis"). This manuscript is an overview of the century of research (1850-1950) that followed the emergence of this clinical entity, with a focus on the hitherto under-explored English Canadian perspective. Using journal articles, reviews, and case studies, this historiographical paper reviews what may be some of the earliest recorded cases of MS in Canada, and outlines the diagnostic challenges that confronted early Canadian physicians in their encounters with MS. Early Canadian attempts to characterize the aetiology and epidemiology of MS and treat it are also discussed. These activities were influenced by developments in the field in Europe and the United States, and helped set the stage for the modern era of immunologic and therapeutic research on MS.

  15. [Heinrich Hoffmann's Der Struwwelpeter (1845/1859): a parody on the romantic cult of childhood].

    PubMed

    Wesseling, Lies

    2006-01-01

    This article analyzes the cultural dynamics of the construction and deconstruction of childhood images, by means of a case study of Heinrich Hoffmann's classic picture book, Der Struwwelpeter (1845/1859). Childhood images are the joint product of sciences (especially anthropology, pedagogy and developmental psychology) and arts (especially painting, photography and (children's) literature). These images are historically variable, because childhood is the permanent target of idealization and demystification. This article interprets Der Struwwelpeter as a demystication of Romantic idealizations of childhood as propounded by Romantic Naturphilosophie and, more specifically, the pedagogy of Friedrich Fröbel (1772-1852). In my view, this picture book satirizes the developmentalism and the pastoryl idyll which informed the Romantic image of childhood, through its verbal and visual components. As I argue at length, this satire directly bears upon leading scientific and political controversies of Hoffmann's time.

  16. Crystallography from Haüy to Laue: controversies on the molecular and atomistic nature of solids.

    PubMed

    Kubbinga, Henk

    2012-01-01

    The history of crystallography has been assessed in the context of the emergence and spread of the molecular theory. The present paper focuses on the 19th century, which saw the emancipation of crystallography as a science sui generis. Around 1800, Laplace's molecularism called the tune in the various sciences (physics, chemistry, biology, crystallography). In crystallography, two schools opposed each other: that of Weiss, in Berlin, and that of Haüy, in Paris. Symmetry proved essential. It will be shown how the lattice theory arose in an essentially molecular framework and how group theory imposed itself. The salt hydrates suggested the idea of (two or more) superimposed molecular lattices. Gradually it became clear that an ultimate lattice theory ought to be atomic. The experiments of Laue, Friedrich and Knipping confirmed that atomic basis.

  17. 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.

  18. 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

  19. Part I: Houtermans

    NASA Astrophysics Data System (ADS)

    Frenkel, Victor Ya.

    The following sections are included: * PROFESSOR FRIEDRICH HOUTERMANS: WORKS, LIFE, FATE * Introduction * Beginnings * Göttingen * Berlin * 1933 * London * Impressions of Kharkov * Kharkov: 1935-1937 * Arrests * Last Months in the USSR (From Charlotte Houtermans' Diary) * Descent into the Prisons: 1937-39 * From Desperation to Hope (Continuation of Charlotte Houtermans' Diary) * Fighting for Freedom * Descent into the Prisons: 1939-40 * The Bridge over the River Bug * On the Other Shore * Back in Berlin * The Plutonium Report * "They should Accelerate!" * Back in Kharkov * Kharkov Trace (What Happened at the Session of the Academy of Sciences) * Who are Beck and Godin? * War's End * The Age of the Earth * Friends on Houtermans * Chronology * Appendices (Compiled by the Editor) * Last Diary * Odessa 1930 * Chronological Report of my Life in Russian Prisons * Alexander Weissberg's Letter * After the War

  20. The Pulkovo Observatory on the Centuries' Borderline

    NASA Astrophysics Data System (ADS)

    Abalakin, Viktor K.

    The present paper deals with the development of astrophysical research at the Pulkovo Observatory (now: the Central (Pulkovo) Astronomical Observatory of the Russian Academy of Sciences) at adjacent time periods separated by the threshold between the 19th and the 20th centuries. The Pulkovo Observatory had been inaugurated in 1839. Its traditional field of research work was astrometry. The confirmation of light absorption phenomenon in interstellar space by Friedrich Georg Wilhelm Struve marked the turn of the Observatory's research programs toward astrophysics. New tendencies in the development of contemporaneous astronomy in Russia were pointed out by Otto Struve in his paper “About the Place of Astrophysics in Astronomy” presented in 1866 to the Saint-Petersburg Academy of Sciences. Wide-scale astrophysical studies were performed at Pulkovo Observatory around 1900 during the directorships of Theodore Bredikhin, Oscar Backlund and Aristarchos Belopolsky.

  1. Zach's impact on the sciences

    NASA Astrophysics Data System (ADS)

    Brosche, Peter

    We recall Zach's direct contributions to various sciences, such as his involvement in the search for the first minor planets, the measurement of the Earth at small and large scales - including the deviation of the plumb line - and the development of instruments. Apart from these highlights, he shouldered a fair share of the more tedious but basic parts of the labour involved: the observations for and construction of solar tables, star catalogues and nutation tables. He was a sought-after expert for the founding and equipment of observatories (Gotha, Marseille, Naples, Marlia), a teacher who introduced practical astronomy for young scientists (such as Carl Friedrich Gauss and Carl Burckhardt) and encouraged, advised and supervised many scientific travellers (Alexander v. Humboldt, Karsten Niebuhr, Eduard Rüuppell). Beyond that, he promoted communication amongst astronomers in a most outstanding and productive manner, by his specialized journals and by the first astronomical meeting in 1798.

  2. [On natural history museums and their purpose. A lecture given by Leopold von Buch (1774-1853) in April 1838].

    PubMed

    Kröger, Björn

    2011-12-01

    A manuscript of a lecture by the Prussian geologist Leopold von Buch given at the Berlin Society of the Friends of the Humanity was discovered at the Museum für Naturkunde, Berlin. The text is a raw version of a passionate plea for the formation of natural history collections as science places, with a partly biting humor. Based on until now unknown anecdotes about naturalists like Kaspar Maria Graf Sternberg (1761-1838) and Friedrich Wilhelm Hoeninghaus (1771-1854) Leopold von Buch argues with von Sternberg for the scientific value of natural history collections. The repeating references to the works of Goethe and an extensive addendum of various Dante translations into German are striking. The lecture manuscript complements our knowledge about the thinking of this important geologist, and provides new insights into the science policy of his time.

  3. Gasturbinen-Kraftwerke

    NASA Astrophysics Data System (ADS)

    Zahoransky, Richard; Allelein, Hans-Josef; Bollin, Elmar; Oehler, Helmut; Schelling, Udo

    Stationäre Gasturbinen-Kraftwerke zur Stromerzeugung wurden zuerst von Holzwarth Anfang des 20. Jahrhunderts zur kommerziellen Reife entwickelt und bis zum 2. Weltkrieg hergestellt. Hierbei handelte es sich um Verpuffungs-Gasturbinen mit isochorer Wärmezufuhr [6.1]. 1939 präsentierte die Firma BBC auf der Zürcher Landesausstellung die erste stationäre Gasturbine mit isobarer Wärmezufuhr, nach deren Prinzip die heutigen Gasturbinen aufgebaut sind. Diese 4 MW Maschine ist noch heute in Neuchâtel betriebsbereit. Friedrich Stolze gilt als Erfinder dieser Gasturbinen-Bauweise. Seine erste, schon 1904 bei BBC gebaute Anlage erbrachte wegen zu geringer Maschinenwirkungsgrade und zu geringer Turbineneintrittstemperatur jedoch keine Nutzleistung [6.2].

  4. PREFACE: 15th International Conference on the Physics of Highly Charged Ions

    NASA Astrophysics Data System (ADS)

    Zou, Yaming; Hutton, Roger

    2011-07-01

    , under the Chairmanship of Professors Thomas Stoehlker and Joachim Ullrich. We wish them all the best with their plans and look forward to meeting you all again in 2012. Committees, Exhibitors and Sponsors HCI2010 International Advisory Committee F Aumayr (Austria) T Azuma (Japan) P Beiersdorfer (USA) J Burgdoerfer (Austria) A Cassimi (France) H Cederquist (Sweden) J Costello (Ireland) F Currell (UK) R Hoekstra (Holland) X Ma (China) F Martín (Spain) A Mueller (German) N Nakamura (Japan) M Pajek (Poland) R Rivarola (Argentina) Z Rudzikas (Lithuania) V Shabaev (Russia) R Schuch (Sweden) T Stoehlker (Germany) J Tanis (USA) L Tribedi (India) K Tokési (Hungary) J Ullrich (Germany) D Vernhet (France) Y Zou (China) T Zouros (Greece) HCI2010 Local Organizing Committee Co-chairs: Yaming Zou and Roger Hutton (Fudan university) Secretaries: Baoren Wei and Yunqing Fu (Fudan University) Treasurers: Xiuqing Xu and Daoli Xu (Shanghai Nuclear Society) Members Chongyang Chen (Shanghai) Jianmin Yuan (Changsha) Jun Yan (Beijing) Chenzhong Dong (Lanzhou) Xiaohong Cai (Lanzhou) Xinwen Ma (Lanzhou) Xuru Duan (Sichuan) Baohan Zhang (Sichuan) Exhibitors Andor Technology andor.com Shanghai Kelin Technology Development Co. Ltd chnkelin.com Varian Inc. varianinc.com Sponsors Natural Science Foundation of China International Union of Pure and Applied Physics (IUPAP) Fudan University

  5. Tree ring and ice core time scales around the Santorini eruption

    NASA Astrophysics Data System (ADS)

    Löfroth, Elin; Muscheler, Raimund; Aldahan, Ala; Possnert, Göran; Berggren, Ann-Marie

    2010-05-01

    When studying cosmogenic radionuclides in ice core and tree ring archives around the Santorini eruption a ~20 year discrepancy was found between the records (Muscheler 2009). In this study a new 10Be dataset from the NGRIP ice core is presented. It has a resolution of 7 years and spans the period 3752-3244 BP (1803-1295 BC). The NGRIP 10Be record and the previously published 10Be GRIP record were compared to the IntCal datasets to further investigate the discrepancy between the ice core and tree ring chronologies. By modelling the 14C production rate based on atmospheric 14C records a comparison could be made to the 10Be flux which is assumed to represent the 10Be production rate. This showed a time shift of ~23 years between the records. The sensitivity of the results to changes in important model parameters was evaluated. Uncertainties in the carbon cycle model cannot explain a substantial part of the timing differences. Potential influences of climate and atmospheric processes on the 10Be deposition were studied using δ18O from the respective cores and GISP2 ice core ion data. The comparison to δ18O revealed a small but significant correlation between 10Be flux and δ18O when the 14C-derived production signal was removed from the 10Be curves. The ion data, as proxies for atmospheric circulation changes, did not show any correlations to the 10Be record or the 10Be/14C difference. When including possible data uncertainties there is still a minimum discrepancy of ~10 years between the 10Be ice core and the 14C tree ring record. Due to lack of alternative explanations it is concluded that the ice core and/or the tree ring chronologies contains unaccounted errors in this range. This also reconciles the radiocarbon 1627-1600 BC (Friedrich et al., 2006) and ice core 1642±5 BC (Vinther et al., 2006) datings of the Santorini eruption. Friedrich, W.L., Kromer, B., Friedrich, M., Heinemeier, J., Pfeiffer, T., & Talamo, S., 2006: Santorini eruption radiocarbon dated to

  6. Experimental and numerical investigations of the effects of incident turbulence on the flow over a surface-mounted prism

    NASA Astrophysics Data System (ADS)

    El-Okda, Yasser Mohamed

    The issue of the effects of free stream turbulence on the flow field over a surface-mounted prism is examined through experimental and numerical investigations. In the experimental studies, particle image velocimetry measurements are conducted in the ESM water tunnel at Reynolds number of 9,600 and under two cases of turbulent inflow conditions. The results show that the mean flow separation, reattachment and parameters such as mean velocity, root mean square, Reynolds stresses and turbulent kinetic energy are affected by the turbulence characteristics of the incident flow. The instantaneous dynamics of the interactions between the separating shear layer and the solid wall and between the shear layer and the turbulence in the incident flow are detailed. In the numerical studies, large eddy simulations of the flow over a surface-mounted prism under two inflow conditions; namely, smooth inflow and isotropic homogeneous turbulence inflow, are performed. The use of a fifth-order scheme (CUD-II-5), which is a member of a family of Compact Upwind Difference schemes, in large eddy simulations of this flow is assessed. The performance of this scheme is validated by comparing the rate of temporal decay of isotropic turbulence with available experimental measurements for grid-generated turbulence. The results show that the spectra are sensitive to the method of flux vector splitting needed for the implementation of the upwind scheme. With van Leer splitting, the CUD-II-5 scheme is found to be too dissipative. On the other hand, using the Lax-Friedrichs vector splitting yields good agreement with experiments by controlling the level of artificial dissipation. This led us to recommend a new procedure, we denote by C6CUD5 scheme, that combines a compact sixth-order scheme with the CUD-II-5 scheme for large eddy simulation of complex flows. The simulation results, including flow patterns, pressure fields and turbulence statistics show that the CUD-II-5 scheme, with Lax-Friedrichs

  7. Parameterisation of clastic sediments including benthic structures

    NASA Astrophysics Data System (ADS)

    Bobertz, B.; Harff, J.; Bohling, B.

    2009-02-01

    The sediment transport processes in the south-western Baltic Sea are predicted by means of a numerical model in the project DYNAS. There are two sediment parameters that influence the results of modelling remarkably: critical shear stress velocity and bottom roughness. This paper presents the way how to parameterise these factors and extrapolate them into the investigation area. The critical shear stress velocity is parameterised basing on grain size data, combining approximations after Hjulström [Hjulström, F., 1935: Studies in the morphological activity of rivers as illustrated by the river Fyris. Geological Institution of University of Uppsala: Bulletin (25): 221-528.], Shields [Shields, A., 1936: Anwendung der Ähnlichkeits-Mechanik und der Turbulenzforschung auf die Geschiebebewegung. Mitteilungen der Preussischen Versuchsanstalt für Wasserbau und Schiffahrt (26): 26 pp.] and Bohling [Bohling, B., 2003: Untersuchungen zur Mobilität natürlicher und anthropogener Sedimente in der Mecklenburger Bucht. unpublished doctoral thesis, Mathematisch-Naturwissenschaftliche Fakultät, Ernst-Moritz-Arndt-Universität Greifswald/Germany, 156 pp.]. The roughness length, in the case of absence of macro zoo-benthos and their structures, is parameterised basing on grain size too employing Soulsby [Soulsby, R.L., 1997: Dynamics of Marine Sands: a Manual for Practical Applications. London, Thomas Telford Publications. 249 pp.], Nielsen [Nielsen, P., 1983: Analytical determination of nearshore wave height variation due to refraction shoaling and friction. Coastal Engineering 7, 233-251.] and Yalin [Yalin, M.S., 1977: Mechanics of Sediment Transport. Pergamon Press, New York. 298 pp.]. No equivalent simple parameterisations for biologically caused bed roughness exist. Here, findings of Friedrichs [Friedrichs, M., 2004: Flow-induced effects of macro zoo-benthic structures on the near-bed sediment transport. Dissertation, Universität Rostock, 80 S.] and estimations by the DYNAS

  8. IRI, an International Standard for the Ionosphere

    NASA Astrophysics Data System (ADS)

    Bilitza, D.; Reinisch, B.; Triskova, L.; Friedrich, M.

    2003-04-01

    The International Reference Ionosphere (IRI) is a data-based model of the ionosphere that has been steadily improved and updated by a joint working group of the Committee on Space Research and the International Union of Radio Science. We will report about the most recent IRI workshops and the improvements and additions planned for the next version of the model. In particular new models will be included for the D-region electron density (Friedrich et al., 2002), and for the ion densities (Triskova et al., 2003) the latter based on Atmosphere Explorer C, D, E and Intercosmos 24 data. A correction term will be introduced in the topside electron density model to alleviate problems at high solar activities and high altitudes (Bilitza, 2002). A special IRI task groups is working on an occurrence probability model for spread-F (Abdu et al., 2003) for inclusion in IRI. A quantitative description of ionospheric variability (standard deviation from monthly mean) is the goal of a special IRI task force activity at the International Center for Theoretical Physics (Radicella 2002). We will also report about activities to update IRI with actual measurements and thus obtain a more accurate description of the actual ionosphere. A proposal to make the IRI model the ISO standard for the ionosphere is now pending before the International Standardization Organization (ISO). The IRI homepage is at http://nssdc.gsfc.nasa.gov/space/model/ionos/iri.html and a web-interface for computing and plotting IRI parameters can be found at http://nssdc.gsfc.nasa.gov/space/model/models/iri.html . Abdu, M. A., J. R de Souza, I. S. Batista, and J. H. A. Sobral, Equatorial Spread F statistics and their empirical modeling for the IRI: A regional model for the Brazilian longitude sector, Adv. Space Res., in press, 2003. Triskova, L., V. Truhlik and J. Smilauer, An empirical model of ion composition in the outer ionosphere, Adv. Space Res., in press, 2003 Bilitza, D., A Correction for the IRI Topside

  9. RBIS - An Environmental Information System

    NASA Astrophysics Data System (ADS)

    Zander, F.; Kralisch, S.

    2012-04-01

    The River Basin Information System (RBIS) developed at the Department of Geoinformatics at the Friedrich Schiller University of Jena provides a modular structured and web-based platform for environmental data management and data sharing (http://www.rbis.uni-jena.de). The system is used in several multidisciplinary research projects and provides user-friendly functions for the management, analysis, visualization and presentation of different types of data. These types of data include time series data (e.g. hydrological, climatologically …), geodata, documents and more domain specific modules for example related to soil, vegetation, scenarios, simulation models or indicators. One main focus lies on the maintenance on meta-data to make sure information about data provenance and responsible parties are preserved. Furthermore the fine grained user and permission management of RBIS take care about the access and manipulation rights of all stored data. For an easy data exchange of time series data and other data types RBIS provides several interfaces. One example is a prototypical implementation using OGC standards (Sensor Observation Service (SOS) and WaterML2.0). Since RBIS is used for data in research regions located in different countries (e.g. Brazil, Vietnam, Angola, Chile, Germany) a Multilanguage support was added to address not only research project partners but also local stakeholder and public. We will present the structure, modules, main functions, permission management and interfaces for data exchange of RBIS together with selected examples of RBIS instances.

  10. FLECHAS - A new échelle spectrograph at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.; Avila, G.; Guirao, C.

    The new échelle spectrograph FLECHAS (Fibre Linked ECHelle Astronomical Spectrograph) is in operation at the Nasmyth-focus of the 0.9 m telescope of the University Observatory Jena. FLECHAS is equipped with a sensitive back-illuminated and midband coated CCD-detector, as well as with a calibration unit for flatfield and wavelength-calibration. The spectrograph covers the spectral range between about 3900 and 8100 Åand exhibits a resolving power of R˜9300. In this article all technical characteristics of FLECHAS are described and examples of the first astronomical observations obtained with the new instrument in July 2013 at the University Observatory Jena are presented, among them the first light spectra taken with FLECHAS, simultaneous imaging and spectroscopic observations, the determination of the detection limit of the instrument, the spectroscopy of stars of different spectral types and of faint extended objects, as well as the Li-line detection in the spectra of young solar-like stars. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  11. A computational approach to negative priming

    NASA Astrophysics Data System (ADS)

    Schrobsdorff, H.; Ihrke, M.; Kabisch, B.; Behrendt, J.; Hasselhorn, M.; Herrmann, J. Michael

    2007-09-01

    Priming is characterized by a sensitivity of reaction times to the sequence of stimuli in psychophysical experiments. The reduction of the reaction time observed in positive priming is well-known and experimentally understood (Scarborough et al., J. Exp. Psycholol: Hum. Percept. Perform., 3, pp. 1-17, 1977). Negative priming—the opposite effect—is experimentally less tangible (Fox, Psychonom. Bull. Rev., 2, pp. 145-173, 1995). The dependence on subtle parameter changes (such as response-stimulus interval) usually varies. The sensitivity of the negative priming effect bears great potential for applications in research in fields such as memory, selective attention, and ageing effects. We develop and analyse a computational realization, CISAM, of a recent psychological model for action decision making, the ISAM (Kabisch, PhD thesis, Friedrich-Schiller-Universitat, 2003), which is sensitive to priming conditions. With the dynamical systems approach of the CISAM, we show that a single adaptive threshold mechanism is sufficient to explain both positive and negative priming effects. This is achieved by comparing results obtained by the computational modelling with experimental data from our laboratory. The implementation provides a rich base from which testable predictions can be derived, e.g. with respect to hitherto untested stimulus combinations (e.g. single-object trials).

  12. Planetary transit observations at the University Observatory Jena: TrES-2

    NASA Astrophysics Data System (ADS)

    Raetz, St.; Mugrauer, M.; Schmidt, T. O. B.; Roell, T.; Eisenbeiss, T.; Hohle, M. M.; Koeltzsch, A.; Vaňko, M.; Ginski, Ch.; Marka, C.; Moualla, M.; Tetzlaff, N.; Seifahrt, A.; Broeg, Ch.; Koppenhoefer, J.; Raetz, M.; Neuhäuser, R.

    2009-05-01

    We report on observations of several transit events of the transiting planet TrES-2 obtained with the Cassegrain-Teleskop-Kamera at the University Observatory Jena. Between March 2007 and November 2008 ten different transits and almost a complete orbital period were observed. Overall, in 40 nights of observation 4291 exposures (in total 71.52 h of observation) of the TrES-2 parent star were taken. With the transit timings for TrES-2 from the 34 events published by the TrES-network, the Transit Light Curve project and the Exoplanet Transit Database plus our own ten transits, we find that the orbital period is P=(2.470614± 0.000001) d, a slight change by ˜ 0.6 s compared to the previously published period. We present new ephemeris for this transiting planet. Furthermore, we found a second dip after the transit which could either be due to a blended variable star or occultation of a second star or even an additional object in the system. Our observations will be useful for future investigations of timing variations caused by additional perturbing planets and/or stellar spots and/or moons. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University Jena and the 80cm telescope of the Wendelstein Observatory of the Ludwig-Maximilians-University Munich.

  13. Photometric monitoring of the young star Par 1724 in Orion

    NASA Astrophysics Data System (ADS)

    Neuhäuser, R.; Koeltzsch, A.; Raetz, St.; Schmidt, T. O. B.; Mugrauer, M.; Young, N.; Bertoldi, F.; Roell, T.; Eisenbeiss, T.; Hohle, M. M.; Vaňko, M.; Ginski, C.; Rammo, W.; Moualla, M.; Broeg, C.

    2009-05-01

    We report new photometric observations of the ˜ 200 000 year old naked weak-line run-away T Tauri star Par 1724, located north of the Trapezium cluster in Orion. We observed in the broad band filters B, V, R, and I using the 90 cm Dutch telescope on La Silla, the 80 cm Wendelstein telescope, and a 25 cm telescope of the University Observatory Jena in Großschwabhausen near Jena. The photometric data in V and R are consistent with a ˜ 5.7 day rotation period due to spots, as observed before between 1960ies and 2000. Also, for the first time, we present evidence for a long-term 9 or 17.5 year cycle in photometric data (V band) of such a young star, a cycle similar to that to of the Sun and other active stars. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University; a telescope of the University Observatory Munich on Mount Wendelstein, the 0.9m ESO-Dutch telescope on La Silla, Chile, and with the All Sky Automated Survey (ASAS) project (www.astrouw.edu.pl/asas).

  14. New brown dwarf candidates in the Pleiades

    NASA Astrophysics Data System (ADS)

    Eisenbeiss, T.; Moualla, M.; Mugrauer, M.; Schmidt, T. O. B.; Raetz, St.; Neuhäuser, R.; Ginski, Ch.; Hohle, M. M.; Koeltzsch, A.; Marka, C.; Rammo, W.; Reithe, A.; Roell, T.; Vaňko, M.

    2009-05-01

    We have performed deep, wide-field imaging on a ˜ 0.4 deg2 field in the Pleiades (Melotte 22). The selected field was not yet target of a deep search for low mass stars and brown dwarfs. Our limiting magnitudes are R˜22 mag and I˜20 mag, sufficient to detect brown dwarf candidates down to 40 MJ. We found 197 objects, whose location in the (I, R-I) color magnitude diagram is consistent with the age and the distance of the Pleiades. Using CTK R and I as well as JHK photometry from our data and the 2MASS survey we were able to identify 7 new brown dwarf candidates. We present our data reduction technique, which enables us to resample, calibrate, and co-add many images by just two steps. We estimate the interstellar extinction and the spectral type from our optical and the NIR data using a two-dimensional χ2 fitting. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich- Schiller-University. Table A3 is available at the CDS via http://cdsarc.u-strasbg.fr/pub/cats/J/AN/330/439

  15. Planetary transit observations at the University Observatory Jena: XO-1b and TrES-1

    NASA Astrophysics Data System (ADS)

    Raetz, St.; Mugrauer, M.; Schmidt, T. O. B.; Roell, T.; Eisenbeiss, T.; Hohle, M. M.; Tetzlaff, N.; Vaňko, M.; Seifahrt, A.; Broeg, Ch.; Koppenhoefer, J.; Neuhäuser, R.

    2009-05-01

    We report on observations of transit events of the transiting planets XO-1b and TrES-1 with a 25 cm telescope of the University Observatory Jena. With the transit timings for XO-1b from all 50 available XO, SuperWASP, Transit Light Curve (TLC)-Project- and Exoplanet Transit Database (ETD)-data, including our own I-band photometry obtained in March 2007, we find that the orbital period is P=(3.941501± 0.000001) d, a slight change by ˜3 s compared to the previously published period. We present new ephemeris for this transiting planet. Furthermore, we present new R-band photometry of two transits of TrES-1. With the help of all available transit times from literature this allows us to refine the estimate of the orbital period: P=(3.0300722± 0.0000002) d. Our observations will be useful for future investigations of timing variations caused by additional perturbing planets and/or stellar spots and/or moons. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University Jena.

  16. Constraints on a Second Planet in the WASP-3 System

    NASA Astrophysics Data System (ADS)

    Maciejewski, G.; Niedzielski, A.; Wolszczan, A.; Nowak, G.; Neuhäuser, R.; Winn, J. N.; Deka, B.; Adamów, M.; Górecka, M.; Fernández, M.; Aceituno, F. J.; Ohlert, J.; Errmann, R.; Seeliger, M.; Dimitrov, D.; Latham, D. W.; Esquerdo, G. A.; McKnight, L.; Holman, M. J.; Jensen, E. L. N.; Kramm, U.; Pribulla, T.; Raetz, St.; Schmidt, T. O. B.; Ginski, Ch.; Mottola, S.; Hellmich, S.; Adam, Ch.; Gilbert, H.; Mugrauer, M.; Saral, G.; Popov, V.; Raetz, M.

    2013-12-01

    There have been previous hints that the transiting planet WASP-3b is accompanied by a second planet in a nearby orbit, based on small deviations from strict periodicity of the observed transits. Here we present 17 precise radial velocity (RV) measurements and 32 transit light curves that were acquired between 2009 and 2011. These data were used to refine the parameters of the host star and transiting planet. This has resulted in reduced uncertainties for the radii and masses of the star and planet. The RV data and the transit times show no evidence for an additional planet in the system. Therefore, we have determined the upper limit on the mass of any hypothetical second planet, as a function of its orbital period. Partly based on (1) observations made at the Centro Astronómico Hispano Alemán (CAHA), operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC), (2) data collected with telescopes at the Rozhen National Astronomical Observatory, and (3) observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  17. Transit timing variation in exoplanet WASP-3b

    NASA Astrophysics Data System (ADS)

    Maciejewski, G.; Dimitrov, D.; Neuhäuser, R.; Niedzielski, A.; Raetz, St.; Ginski, Ch.; Adam, Ch.; Marka, C.; Moualla, M.; Mugrauer, M.

    2010-10-01

    Photometric follow-ups of transiting exoplanets may lead to discoveries of additional, less massive bodies in extrasolar systems. This is possible by detecting and then analysing variations in transit timing of transiting exoplanets. We present photometric observations gathered in 2009 and 2010 for exoplanet WASP-3b during the dedicated transit-timing-variation campaign. The observed transit timing cannot be explained by a constant period but by a periodic variation in the observations minus calculations diagram. Simplified models assuming the existence of a perturbing planet in the system and reproducing the observed variations of timing residuals were identified by three-body simulations. We found that the configuration with the hypothetical second planet of mass ~, located close to the outer 2:1 mean-motion resonance, is the most likely scenario reproducing observed transit timing. We emphasize, however, that more observations are required to constrain better the parameters of the hypothetical second planet in the WASP-3 system. For final interpretation not only transit timing but also photometric observations of the transit of the predicted second planet and high-precision radial velocity data are needed. This paper is based on observations made with the 60-cm telescope of the Rozhen National Astronomical Observatory, which is operated by the Institute of Astronomy, Bulgarian Academy of Sciences, and the 90-cm telescope of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich Schiller University. E-mail: gm@astro.uni-jena.de

  18. Interaction of Deep and Shallow Fluids in the Thuringian Basin, Germany

    NASA Astrophysics Data System (ADS)

    Kukowski, N.; Kley, J.; Totsche, K.

    2012-12-01

    To unriddle the coupled dynamics of near surface and deep fluids in a sedimentary basin on various scales, ranging from pore scale to the extent of a whole basin, is a fundamental goal of INFLUINS (INtegrated FLuid dynamics IN Sedimentary basins), a research initiative of several groups from Friedrich-Schiller University of Jena and their partners. This research association is focusing on the Thuringian basin, Germany, as a natural geo laboratory. In a multidisciplinary approach, embracing different fields of geophysics like seismic reflection profiling or airborne geomagnetics, structural geology, sedimentology, hydrogeology and hydrology, remote sensing, and mineralogy, among others, and including both, field-based and computer-based research, an integral INFLUINS topic is the potential interaction of aquifers within the basin and at its rims. The Thuringian basin is particularly suited to undertake such research as it is of relative small size, about 50 to 100 km, easily accessible, and quite well known from previous studies, and therefore also a perfect candidate for deep drilling. Here we report on first key results of the INLFLUINS initiative including basin architecture and development, geophysical surveying and imaging as well as the nature of actual and paleo fluids. After extensive reflection seismic acquisition had been done in 2011, now carefully chosen areas are geomagnetically surveyed using a full tensor airborne magnetic SQUID gradiometer. Much of this is undertaken in preparation for km-deep drilling which will take place at the end of this year.

  19. Finite-volume component-wise TVD schemes for 2D shallow water equations

    NASA Astrophysics Data System (ADS)

    Lin, Gwo-Fong; Lai, Jihn-Sung; Guo, Wen-Dar

    Four finite-volume component-wise total variation diminishing (TVD) schemes are proposed for solving the two-dimensional shallow water equations. In the framework of the finite volume method, a proposed algorithm using the flux-splitting technique is established by modifying the MacCormack scheme to preserve second-order accuracy in both space and time. Based on this algorithm, four component-wise TVD schemes, including the Liou-Steffen splitting (LSS), van Leer splitting, Steger-Warming splitting and local Lax-Friedrichs splitting schemes, are developed. These schemes are verified through the simulations of the 1D dam-break, the oblique hydraulic jump, the partial dam-break and circular dam-break problems. It is demonstrated that the proposed schemes are accurate, efficient and robust to capture the discontinuous shock waves without any spurious oscillations in the complex flow domains with dry-bed situation, bottom slope or friction. The simulated results also show that the LSS scheme has the best numerical accuracy among the schemes tested.

  20. A Class of TVD Type Combined Numerical Scheme for MHD Equations With a Survey About Numerical Methods in Solar Wind Simulations

    NASA Astrophysics Data System (ADS)

    Feng, Xueshang; Wu, S. T.; Wei, Fengsi; Fan, Quanlin

    2003-04-01

    It has been believed that three-dimensional, numerical, magnetohydrodynamic (MHD) modelling must play a crucial role in a seamless forecasting system. This system refers to space weather originating on the sun; propagation of disturbances through the solar wind and interplanetary magnetic field (IMF), and thence, transmission into the magnetosphere, ionosphere, and thermosphere. This role comes as no surprise to numerical modelers that participate in the numerical modelling of atmospheric environments as well as the meteorological conditions at Earth. Space scientists have paid great attention to operational numerical space weather prediction models. To this purpose practical progress has been made in the past years. Here first is reviewed the progress of the numerical methods in solar wind modelling. Then, based on our discussion, a new numerical scheme of total variation diminishing (TVD) type for magnetohydrodynamic equations in spherical coordinates is proposed by taking into account convergence, stability and resolution. This new MHD model is established by solving the fluid equations of MHD system with a modified Lax-Friedrichs scheme and the magnetic induction equations with MacCormack II scheme for the purpose of developing a combined scheme of quick convergence as well as of TVD property. To verify the validation of the scheme, the propagation of one-dimensional MHD fast and slow shock problem is discussed with the numerical results conforming to the existing results obtained by the piece-wise parabolic method (PPM). Finally, some conclusions are made.

  1. Current considerations about Merkel cells.

    PubMed

    Lucarz, Annie; Brand, Gerard

    2007-05-01

    Since the discovery of Merkel cells by Friedrich S. Merkel in 1875, knowledge of their structure has increased with the progression of new technologies such as electron and laser microscopy, and immunohistochemical techniques. For most vertebrates, Merkel cells are located in the basal layer of the epidermis and characterized by dense-core granules that contain a variety of neuropeptides, plasma membrane spines and cytoskeletal filaments consisting of cytokeratins and desmosomes. The presence of the two latter structures would suggest that Merkel cells originate from the epidermis rather than from the neural crest, even though such a hypothesis is not unanimously accepted. The function of the Merkel cell is also very controversial. For a long time, it has been accepted that Merkel cells with associated nerve terminals act as mechanoreceptors although the transduction mechanism has not yet been elucidated. Merkel cells that do not make contact with nerve terminals have an endocrine function. The present review aims to shed new and comparative light on this field with an attempt to investigate the stimuli that Merkel cells are able to perceive.

  2. Demographische Entwicklung in der Metropolregion Berlin-Brandenburg

    NASA Astrophysics Data System (ADS)

    Beyer, Wolf; Bluth, Friedrich

    〝Denn eins ist sicher: Die Rente.`` Der vielzitierte Satz des früheren Arbeits- und Sozialministers Norbert Blüm klingt heute vielen wie Hohn. Der Altersaufbau der deutschen Bevölkerung erinnert grafisch immer mehr an einen Baum auf dünnem Stämmchen als an eine Pyramide. Angesichts dessen rücken demographische Entwicklungen mehr und mehr in den Fokus der Öffentlichkeit. Besonders die neuen Bundesländer sind massiv von Abwanderung und einem nie dagewesenen Geburtenrückgang betroffen.DIPL.-GEOGR. UTE C. BAUERsprach mitFRIEDRICH BLUTHundWOLF BEYERüber die Besonderheiten der demographischen Prozesse in Berlin und Brandenburg. Beyer leitete bis Anfang 2004 das brandenburgische Referat für Raumbeobachtung. Seine Aufgabe bestand darin, Planungsgrundlagen für die Gemeinsame Landesplanung Berlin-Brandenburg(GL) zu schaffen. Dazu zählen auch Bevölkerungsprognosen für die Kreise und Städte Brandenburgs. Bluth ist in der Senatsverwaltung für Stadtentwicklung Berlin beschäftigt und leitet dort die Gruppe 〝Stadtwissen, Stadtentwicklungsmonitoring, Bevölkerungsprognose.``

  3. Representation of quantum mechanical resonances in the Lax-Phillips Hilbert space

    SciTech Connect

    Strauss, Y.; Horwitz, L. P.; Eisenberg, E.

    2000-01-01

    We discuss the quantum Lax-Phillips theory of scattering and unstable systems. In this framework, the decay of an unstable system is described by a semigroup. The spectrum of the generator of the semigroup corresponds to the singularities of the Lax-Phillips S-matrix. In the case of discrete (complex) spectrum of the generator of the semigroup, associated with resonances, the decay law is exactly exponential. The states corresponding to these resonances (eigenfunctions of the generator of the semigroup) lie in the Lax-Phillips Hilbert space, and therefore all physical properties of the resonant states can be computed. We show that the Lax-Phillips S-matrix is unitarily related to the S-matrix of standard scattering theory by a unitary transformation parametrized by the spectral variable σ of the Lax-Phillips theory. Analytic continuation in σ has some of the properties of a method developed some time ago for application to dilation analytic potentials. We work out an illustrative example using a Lee-Friedrichs model for the underlying dynamical system.

  4. PHURBAS: AN ADAPTIVE, LAGRANGIAN, MESHLESS, MAGNETOHYDRODYNAMICS CODE. I. ALGORITHM

    SciTech Connect

    Maron, Jason L.; McNally, Colin P.; Mac Low, Mordecai-Mark E-mail: cmcnally@amnh.org

    2012-05-01

    We present an algorithm for simulating the equations of ideal magnetohydrodynamics and other systems of differential equations on an unstructured set of points represented by sample particles. Local, third-order, least-squares, polynomial interpolations (Moving Least Squares interpolations) are calculated from the field values of neighboring particles to obtain field values and spatial derivatives at the particle position. Field values and particle positions are advanced in time with a second-order predictor-corrector scheme. The particles move with the fluid, so the time step is not limited by the Eulerian Courant-Friedrichs-Lewy condition. Full spatial adaptivity is implemented to ensure the particles fill the computational volume, which gives the algorithm substantial flexibility and power. A target resolution is specified for each point in space, with particles being added and deleted as needed to meet this target. Particle addition and deletion is based on a local void and clump detection algorithm. Dynamic artificial viscosity fields provide stability to the integration. The resulting algorithm provides a robust solution for modeling flows that require Lagrangian or adaptive discretizations to resolve. This paper derives and documents the Phurbas algorithm as implemented in Phurbas version 1.1. A following paper presents the implementation and test problem results.

  5. 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.

  6. The 'chemistry of space': the sources of Hermann Grassmann's scientific achievements.

    PubMed

    Petsche, Hans-Joachim

    2014-10-01

    Albert Lewis's article (Annals of Science, 1977) analysing the influence of Friedrich Schleiermacher on Hermann Grassmann, stimulated many different studies on the founder of n-dimensional outer algebra. Following a brief outline of the various, sometimes diverging, analyses of Grassmann's creative thinking, new research is presented which confirms Lewis's original contribution and widens it considerably. It will be shown that: i. Grassmann, although a self-taught mathematician, was at the centre of a hitherto understated intellectual trend, which was defining for Germany. Initiated by Pestalozzi's concept of elementary mathematical education and culminating in the modern mathematics of the late 19th Century, it was reflected in the contributions of Grassmann, Riemann, Jacobi and Eisenstein. ii. Hermann Grassmann, his father Justus, and his brother Robert were all demonstrably influenced by Schleiermacher's dialectic; however the two brothers responded to it in very different ways. iii. Whilst the more philosophical parts of Hermann's 1844 Extension Theory are characterised by the influence of Schleiermacher and also by the mathematical knowledge of his father, the entire development of this work is the unfolding of a single idea based on the father's interpretation of combinatorial multiplication as a 'chemical conjunction', which was developed largely dialectically by Hermann. PMID:25470887

  7. The 'chemistry of space': the sources of Hermann Grassmann's scientific achievements.

    PubMed

    Petsche, Hans-Joachim

    2014-10-01

    Albert Lewis's article (Annals of Science, 1977) analysing the influence of Friedrich Schleiermacher on Hermann Grassmann, stimulated many different studies on the founder of n-dimensional outer algebra. Following a brief outline of the various, sometimes diverging, analyses of Grassmann's creative thinking, new research is presented which confirms Lewis's original contribution and widens it considerably. It will be shown that: i. Grassmann, although a self-taught mathematician, was at the centre of a hitherto understated intellectual trend, which was defining for Germany. Initiated by Pestalozzi's concept of elementary mathematical education and culminating in the modern mathematics of the late 19th Century, it was reflected in the contributions of Grassmann, Riemann, Jacobi and Eisenstein. ii. Hermann Grassmann, his father Justus, and his brother Robert were all demonstrably influenced by Schleiermacher's dialectic; however the two brothers responded to it in very different ways. iii. Whilst the more philosophical parts of Hermann's 1844 Extension Theory are characterised by the influence of Schleiermacher and also by the mathematical knowledge of his father, the entire development of this work is the unfolding of a single idea based on the father's interpretation of combinatorial multiplication as a 'chemical conjunction', which was developed largely dialectically by Hermann. PMID:25508514

  8. Heights integrated model as instrument for simulation of hydrodynamic, radiation transport, and heat conduction phenomena of laser-produced plasma in EUV applications.

    SciTech Connect

    Sizyuk, V.; Hassanein, A.; Morozov, V.; Sizyuk, T.; Mathematics and Computer Science

    2007-01-16

    The HEIGHTS integrated model has been developed as an instrument for simulation and optimization of laser-produced plasma (LPP) sources relevant to extreme ultraviolet (EUV) lithography. The model combines three general parts: hydrodynamics, radiation transport, and heat conduction. The first part employs a total variation diminishing scheme in the Lax-Friedrich formulation (TVD-LF); the second part, a Monte Carlo model; and the third part, implicit schemes with sparse matrix technology. All model parts consider physical processes in three-dimensional geometry. The influence of a generated magnetic field on laser plasma behavior was estimated, and it was found that this effect could be neglected for laser intensities relevant to EUV (up to {approx}10{sup 12} W/cm{sup 2}). All applied schemes were tested on analytical problems separately. Benchmark modeling of the full EUV source problem with a planar tin target showed good correspondence with experimental and theoretical data. Preliminary results are presented for tin droplet- and planar-target LPP devices. The influence of three-dimensional effects on EUV properties of source is discussed.

  9. An Act of Scientific Creativity: Meitner, Frisch, and Nuclear Fission

    NASA Astrophysics Data System (ADS)

    Stuewer, Roger H.

    2002-04-01

    The dominant event that lay in the background to Werner Heisenberg's fateful meeting with Niels Bohr in occupied Copenhagen in September 1941 was the discovery and interpretation of nuclear fission three years earlier. Michael Frayn has explored that meeting in his play "Copenhagen" in an act of extraordinary literary creativity. In this talk I will explore Lise Meitner's and Otto Robert Frisch's interpretation of nuclear fission as an act of extraordinary scientific creativity. My aim is to understand historically how it was possible for Meitner and Frisch, and only Meitner and Frisch, to arrive at their interpretation as they talked and walked in the snow in the small Swedish village of Kungälv over the Christmas holidays in December 1938. This will require us to examine the history of the liquid-drop model of the nucleus over the preceding decade, from George Gamow's conception of that model in 1928, through Heisenberg and Carl Friedrich von Weizsäcker's extension of it between 1933 and 1936, and finally through Bohr's use of it in his theory of the compound nucleus between 1936 and 1938. We will see how Meitner and Frisch combined their different knowledge of these developments creatively to arrive at their momentous interpretation of nuclear fission.

  10. On the number of eigenvalues of a model operator in fermionic Fock space

    NASA Astrophysics Data System (ADS)

    Muminov, Zahriddin; Ismail, Fudziah; Eshkuvatov, Zainidin

    2013-04-01

    We consider a model describing a truncated operator H (truncated with respect to the number of particles) acting in the direct sum of zero-, one-, and two-particle subspaces of a fermionic Fock space Script Fa(L2(Bbb T3)) over L2(Bbb T3). We admit a general form for the "kinetic" part of the hamiltonian H, which contains a parameter γ to distinguish the two identical particles from the third one. In this note: (i) We find a critical value γ* for the parameter γ that allows or forbids the Efimov effect (infinite number of bound states if the associated generalized Friedrichs model has a threshold resonance) and we prove that only for γ < γ* the Efimov effect is absent, while this effect exists for any γ > γ*. (ii) In the case γ > γ* we also establish the following asymptotics for the number N(z) of eigenvalues z below Emin, the lower limit of the essential spectrum of H:

  11. THE NEOLIBERAL TURN IN AMERICAN HEALTH CARE.

    PubMed

    Gaffney, Adam

    2015-01-01

    Leaving millions both uninsured and underinsured, the Affordable Care Act does not create a system of universal health care in the United States. To understand its shortcomings, we have to understand it as part of a historic shift in the political economy of American health care. This "neoliberal turn" began as a reaction against the welfare state as it expanded during the New Deal and post-World War II period. What began as a movement associated with philosophers like Friedrich Hayek ultimately had a powerful impact via the attraction of powerful corporate sponsors and political supporters, and it was to historically transform American health care thought and organization. In health policy circles, for example, it can be seen in a rising emphasis on "moral hazard," overuse, and cost sharing above a concern with universalism and equity. It was likewise manifested by the corporatization of the health maintenance organization and the rise of the "consumer-driven" health care movement. By the time of the health care reform debate, the influence of corporate "stakeholders" was to prove predominant. These developments, however, must be construed as connected parts of a much larger political transformation, reflected in rising inequality and privatization, occurring both domestically and internationally. PMID:26460446

  12. Vision loss and hearing loss in painting and musical composition.

    PubMed

    Marmor, Michael F

    2014-07-01

    This article considers the impact of vision and hearing loss on great painters and musical composers. The visual work of Mary Cassatt, Georgia O'Keeffe, Edgar Degas, and Claude Monet all showed alterations as their vision failed. In contrast, Gabriel Fauré, Bedřich Smetana, and Ludwig von Beethoven wrote many of their best compositions while totally deaf, and Georg Friedrich Handel and Frederick Delius struggled to compose late in life when they lost their vision (although their hearing remained excellent). There are 2 major distinctions between the role of vision and hearing for these artistic disciplines. First, there is a surrogate means of "hearing" music, through the musical score, which allows composers to write and edit music while totally deaf. The greatest problem with deafness for a skilled composer is interference from internal noise (tinnitus). There is no surrogate for vision to allow a painter to work when the subject is a blur or the colors on the canvas cannot be distinguished. Second, although the appreciation of art is visual and that of music is auditory, the transcription of both art and musical composition is visual. Thus, visual loss does pose a problem for a composer accustomed to working with good sight, because it disrupts habitual methods of writing and editing music.

  13. [The influence of music on pictorial expression of young women--a comparative study of different music styles].

    PubMed

    Schiltz, L; Maugendre, M; Brytek-Matera, A

    2010-01-01

    Questing one's personal identity and developing a coherent representation of oneself, the other and the world are major tasks in adolescence. Research showed that a satisfactory resolution of the crisis of adolescence can be favoured by psychological counselling based on artistic mediations. The objective of this study consisted in exploring the effect of music on the pictorial expression of a non clinical sample of female adolescents (N=157) aged from 17 to 28 years. We analysed free drawings realised by the test group with the help of a rating scale constructed in a phenomenological and structural perspective (Schiltz, 2006). The adolescents painted under musical induction. We proposed three different styles of music, i.e. baroque music (Georg Friedrich Händel and Johann Sebastian Bach), classical music (Wolfgang Amadeus Mozart and Ludwig van Beethoven) and polish ethnical music (Kapela ze Wsi Warszawa-Warsaw Village Band). By using non parametric inferential and multi dimensional statistics, we could show that structural characteristics of music styles lead to differences in formal and content variables on the rating scales for the pictures. The results of our exploratory study open some tracks for future research. It would be pertinent to enlarge the population to other categories of age and to investigate the influence of gender.

  14. Schlemm, the body snatcher?

    PubMed

    Winkelmann, Andreas

    2008-01-01

    Friedrich Schlemm (1795-1858) is well known for his original description of the scleral venous sinus, known since as Schlemm's canal. He grew up in a village in the Duchy of Braunschweig (Brunswick). As his family could not afford higher education, he was apprenticed to a barber-surgeon in Braunschweig. This gave him the opportunity to study anatomy and surgery at the local Anatomico-Surgical Institute. Recently discovered archival sources demonstrate that, in June of 1816, Schlemm and a fellow student disinterred the body of a deceased woman late at night in a Braunschweig churchyard to bring the body to this Institute and study the effects of rickets on the woman's bones. They were caught and sentenced to 4 weeks of prison. Subsequently, Schlemm left Braunschweig and found work as a low-rank army surgeon in Berlin. Professor Rudolphi, the director of the Berlin Institute of Anatomy, took note of Schlemm's manual dexterity in anatomical dissection and supported his impressive career. Schlemm eventually became full professor of anatomy in 1833 and spent his remaining 25 years in Berlin with a focus on teaching students and training surgeons. As historical background information is largely lacking in this regard, it is impossible to decide whether Schlemm's episode of grave robbing was a solitary instance or a more common method of acquiring bodies for anatomical instruction in early 19th century Germany. PMID:18396022

  15. Relativistic Flows Using Spatial And Temporal Adaptive Structured Mesh Refinement. I. Hydrodynamics

    SciTech Connect

    Wang, Peng; Abel, Tom; Zhang, Weiqun; /KIPAC, Menlo Park

    2007-04-02

    Astrophysical relativistic flow problems require high resolution three-dimensional numerical simulations. In this paper, we describe a new parallel three-dimensional code for simulations of special relativistic hydrodynamics (SRHD) using both spatially and temporally structured adaptive mesh refinement (AMR). We used method of lines to discrete SRHD equations spatially and used a total variation diminishing (TVD) Runge-Kutta scheme for time integration. For spatial reconstruction, we have implemented piecewise linear method (PLM), piecewise parabolic method (PPM), third order convex essentially non-oscillatory (CENO) and third and fifth order weighted essentially non-oscillatory (WENO) schemes. Flux is computed using either direct flux reconstruction or approximate Riemann solvers including HLL, modified Marquina flux, local Lax-Friedrichs flux formulas and HLLC. The AMR part of the code is built on top of the cosmological Eulerian AMR code enzo, which uses the Berger-Colella AMR algorithm and is parallel with dynamical load balancing using the widely available Message Passing Interface library. We discuss the coupling of the AMR framework with the relativistic solvers and show its performance on eleven test problems.

  16. The Wolffian roots of Kant's teleology.

    PubMed

    van den Berg, Hein

    2013-12-01

    Kant's teleology as presented in the Critique of Judgment is commonly interpreted in relation to the late eighteenth-century biological research of Johann Friedrich Blumenbach. In the present paper, I show that this interpretative perspective is incomplete. Understanding Kant's views on teleology and biology requires a consideration of the teleological and biological views of Christian Wolff and his rationalist successors. By reconstructing the Wolffian roots of Kant's teleology, I identify several little known sources of Kant's views on biology. I argue that one of Kant's main contributions to eighteenth-century debates on biology consisted in demarcating biology from metaphysics. Kant rejected Wolffian views on the hierarchy of sciences, according to which propositions specifying the functions of organisms are derived from theological truths. In addition, Kant argued that organic self-organization necessitates a teleological description in order to show that self-organization does not support materialism. By demarcating biology and metaphysics, Kant made a small yet important contribution to establishing biology as a science. PMID:23932232

  17. [The influence of music on pictorial expression of young women--a comparative study of different music styles].

    PubMed

    Schiltz, L; Maugendre, M; Brytek-Matera, A

    2010-01-01

    Questing one's personal identity and developing a coherent representation of oneself, the other and the world are major tasks in adolescence. Research showed that a satisfactory resolution of the crisis of adolescence can be favoured by psychological counselling based on artistic mediations. The objective of this study consisted in exploring the effect of music on the pictorial expression of a non clinical sample of female adolescents (N=157) aged from 17 to 28 years. We analysed free drawings realised by the test group with the help of a rating scale constructed in a phenomenological and structural perspective (Schiltz, 2006). The adolescents painted under musical induction. We proposed three different styles of music, i.e. baroque music (Georg Friedrich Händel and Johann Sebastian Bach), classical music (Wolfgang Amadeus Mozart and Ludwig van Beethoven) and polish ethnical music (Kapela ze Wsi Warszawa-Warsaw Village Band). By using non parametric inferential and multi dimensional statistics, we could show that structural characteristics of music styles lead to differences in formal and content variables on the rating scales for the pictures. The results of our exploratory study open some tracks for future research. It would be pertinent to enlarge the population to other categories of age and to investigate the influence of gender. PMID:20653187

  18. A Study on Plasma Photonic Crystals: Electromagnetic Characteristics Using ICCG-based JEC-CN-FDTD Algorithm

    NASA Astrophysics Data System (ADS)

    Song, Da-Jie; Yang, Ze-kun; Liu, Yu-Jie; Niu, Qing-Xia; Yang, Hong-Wei

    2015-10-01

    We extended the current density convolution finite-difference time-domain (JEC-FDTD) method to plasma photonic crystals using the Crank-Nicolson difference scheme and derived the one-dimensional JEC-Crank-Nicolson (CN)-FDTD iterative equation of plasma photonic crystals. The method eliminated the Courant-Friedrich-Levy (CFL) stability constraint and became completely unconditional stable form. The incomplete Cholesky conjugate gradient (ICCG) algorithm is proposed to solve the equation with a large sparse matrix in the CN-FDTD method as the ICCG method improves the speed of convergence, enhances stability, and reduces memory consumption. The JEC-CN-FDTD method is applied to study the characteristics of time domain and frequency domain in the plasma photonic crystal objects. The high accuracy and efficiency of the JEC-CN-FDTD method are confirmed by computing the characteristic parameters of plasma photonic crystals under different conditions such as the electric field distribution of electromagnetic wave, reflection coefficients, and transmission coefficients. Simulation study showed that the algorithm performed stably and could reduce memory consumption and facilitate computer programming.

  19. Numerical treatment in resonant regime for shallow water equations with discontinuous topography

    NASA Astrophysics Data System (ADS)

    Thanh, Mai Duc

    2013-02-01

    This paper deals with numerical treatments for the shallow water equations with discontinuous topography when the initial data belong to both supersonic region and subsonic region. This kind of data are present in both engineering and rivers, but they are not always well-treated in existing schemes. Our goal is to improve the well-balanced scheme constructed earlier in our work by introducing a computing corrector into the construction of the scheme. First, a further study in the construction of the well-balanced scheme reveals that the errors could make the approximate states near the critical surface that ought to be in one side of the critical surface fall into the other side. This qualitative change, though small, may cause much larger errors following stationary hydraulic jumps formed from these approximate states due to the jump of the bottom. Then, we introduce a corrector in the computing algorithm that selects the equilibrium states in the construction of the well-balanced scheme such that the approximate stationary hydraulic jumps always remain in the right region. Numerical tests show that the well-balanced method using an underlying numerical flux such as Lax-Friedrichs flux, FORCE, GFORCE, or Roe fluxes can approximate very well the exact solution even when the initial data are on both supercritical region and subcritical region.

  20. Spatial distribution of 0-group eel larvae ( Anguilla sp.) in the Sargasso Sea

    NASA Astrophysics Data System (ADS)

    Schoth, M.; Tesch, F.-W.

    1982-09-01

    Both Atlantic eel species ( Anguilla anguilla and A. rostrata) were collected in the Sargasso Sea during the 1979 cruise of the F. R. V. “Anton Dohrn” and R. V. “Friedrich Heincke”. A total of 3,097 0-group larvae were caught during 80 hauls using the Isaacs Kidd Midwater Trawl (55 hauls) and the 9-fold opening and closing net MOCNESS (25 hauls). 11 hauls of the MOCNESS indicated that the larvae showed a preference for the 150 175 m water depth during daytime and for the 50 75 m depth during night. The northern distribution limit seems to coincide with the “18°C-water” at the sea surface. The Antilla current characterised by higher temperatures and salinities could have been the southern distribution limit. The north-easternmost occurrence of A. anguilla was noted at 50°W; the eastern distribution limit of this species could be farther east. The westernmost station at 69°W was positive for both species. A. anguilla, therefore, is very likely to occur beyond this area. The easternmost occurrence of A. rostrata was noted at 52°W though sporadic and with increasing abundance towards the west. At the western end of the network of stations the highest concentration of larvae from both species was recorded. Oceanographic investigations reveal that the distribution of the smaller larvae (size-groups <7 mm and <10 mm) almost coincides with the assumed spawning area.

  1. Politics, Morality, Innovation, and Misrepresentation in Physical Science and Technology

    NASA Astrophysics Data System (ADS)

    Buchwald, Jed Z.

    2016-09-01

    The pressures of politics, the desire to be first in innovation, moral convictions, and the potential dangers of error are all factors that have long been at work in the history of science and technology. Every so often, the need to reach a result may require leaving out a few steps here and there. Historians think and argue best through stories, so what follows are several tales, each of which exemplifies one or more of these aspects, though some reach back nearly two hundred years. The first concerns the depletion of the ozone layer; the second involves the discovery of electric waves by Heinrich Hertz in 1888; the third concerns the controlled production of electromagnetic radiation by Guglielmo Marconi and John Ambrose Fleming in the early 1900s; the fourth portrays the circumstances surrounding Joseph von Fraunhofer's discovery and use of the spectral lines in the 1810s; our final case involves a bitter controversy between the physicist Hermann von Helmholtz and the astronomer Friedrich Zöllner in the 1890s.

  2. General Relativity During the Great War

    NASA Astrophysics Data System (ADS)

    Trimble, Virginia L.

    2016-01-01

    Einstein's (and Hilbert's) equations saw light of day in the darkness of Berlin 1915, as is well known. Moving from this highlight to less conspicuous topics, we find Karl Schwarzschild's solution of those equations (1916) followed shortly by his death. On the observational and American front, Slipher's assemblage of galaxy radial velocities, begun in 1912 with M31, continued apace. Shapley was busily moving us out of the galactic center. Also at Mt. Wilson, Charles St. John looked for gravitational redshift in the solar spectrum in 1917 without firmly detecting it. Adams demonstrated the very low luminosities of Sirius B and 40 Eri B in 1914 (but his attempt at a redshift for the former came only in 1923). Perhaps least well known is that a handful of additional critical theoretical papers date from the war years and describe the Lense-Thirring effect, the Reissner-Nordstrom solution, and a charged solution with a cosmological constant (due to the even more obscure Friedrich Kottler). Some of these came out of neutral Holland, but Kottler served both at Ypres and on the Galician front. Interesting mixes of military service and relativistic contributions are also associated with the names of Friedmann, Le Lemaître, Weyl (of the tensor), Minkowski, Hubble, Flamm, Droste, and Kretschmann. Astronomers in neutral Denmark, Holland and (until 1917) the USA facilitated transmittal of astronomical observations and other news across the battle lines so that Schwarzschild received an obituary in Nature and Moseley one in Naturwissenschaften.

  3. High performance computing aspects of a dimension independent semi-Lagrangian discontinuous Galerkin code

    NASA Astrophysics Data System (ADS)

    Einkemmer, Lukas

    2016-05-01

    The recently developed semi-Lagrangian discontinuous Galerkin approach is used to discretize hyperbolic partial differential equations (usually first order equations). Since these methods are conservative, local in space, and able to limit numerical diffusion, they are considered a promising alternative to more traditional semi-Lagrangian schemes (which are usually based on polynomial or spline interpolation). In this paper, we consider a parallel implementation of a semi-Lagrangian discontinuous Galerkin method for distributed memory systems (so-called clusters). Both strong and weak scaling studies are performed on the Vienna Scientific Cluster 2 (VSC-2). In the case of weak scaling we observe a parallel efficiency above 0.8 for both two and four dimensional problems and up to 8192 cores. Strong scaling results show good scalability to at least 512 cores (we consider problems that can be run on a single processor in reasonable time). In addition, we study the scaling of a two dimensional Vlasov-Poisson solver that is implemented using the framework provided. All of the simulations are conducted in the context of worst case communication overhead; i.e., in a setting where the CFL (Courant-Friedrichs-Lewy) number increases linearly with the problem size. The framework introduced in this paper facilitates a dimension independent implementation of scientific codes (based on C++ templates) using both an MPI and a hybrid approach to parallelization. We describe the essential ingredients of our implementation.

  4. [Famous cases for amputation].

    PubMed

    Klimpel, Volker

    2004-01-01

    After a short historical survey 14 cases of celebrated personalities one woman and 13 men, with the grave handicap of amputation are represented. The causes of the lost limbs, once of the nose, were battle injuries (guns) or accidents. In many cases the protheseology followed the amputation, dependent on the technological level of the day. Often medical providing was bad and terrible. The introduction of anaesthesia changed the amputation technique. During different periods from renaissance to the first half of the twentieth century remarkable fates happened. Heroes as the emperor Friedrich III., the knight Goetz von Berlichingen, well known by the spectacle of Goethe, the scientist Tycho Brahe, the merchant and skipper Peter Stuyvesant, the military men Duke Christian II. of Braunschweig-Lueneburg-Wolfenbuettel, William Bayly, Admiral Lord Nelson and Earl Claus Stauffenberg, the actress Sarah Bernhard, the squadron leader of RAF Douglas R. S. Bader and other gave an excellent example for fulfilled life despite handicap. With their artificial legs, arms or hands they rode, fought, shoot, made sports etc. PMID:15633275

  5. Folding into being: early embryology and the epistemology of rhythm.

    PubMed

    Wellmann, Janina

    2015-03-01

    Historians have often described embryology and concepts of development in the period around 1800 in terms of "temporalization" or "dynamization". This paper, in contrast, argues that a central epistemological category in the period was "rhythm", which played a major role in the establishment of the emerging discipline of biology. I show that Caspar Friedrich Wolff's epigenetic theory of development was based on a rhythmical notion, namely the hypothesis that organic development occurs as a series of ordered rhythmical repetitions and variations. Presenting Christian Heinrich Pander's and Karl Ernst von Baer's theory of germ layers, I argue that Pander and Baer regarded folding as an organizing principle of ontogenesis, and that the principle's explanatory power stems from their understanding of folding as a rhythmical figuration. In a brief discussion of the notion of rhythm in contemporary music theory, I identify an underlying physiological epistemology in the new musical concept of rhythm around 1800. The paper closes with a more general discussion of the relationship between the rhythmic episteme, conceptions of life, and aesthetic theory at the end of the eighteenth century. PMID:26013433

  6. General physiology, experimental psychology, and evolutionism. Unicellular organisms as objects of psychophysiological research, 1877-1918.

    PubMed

    Schloegel, Judy Johns; Schmidgen, Henning

    2002-12-01

    This essay aims to shed new light on the relations between physiology and psychology in the late nineteenth and early twentieth centuries by focusing on the use of unicellular organisms as research objects during that period. Within the frameworks of evolutionism and monism advocated by Ernst Haeckel, protozoa were perceived as objects situated at the borders between organism and cell and individual and society. Scholars such as Max Verworn, Alfred Binet, and Herbert Spencer Jennings were provoked by these organisms to undertake experimental investigations situated between general physiology and psychology that differed from the physiological psychology advocated by Wilhelm Wundt. Some of these investigations sought to locate psychological properties in the molecular structure of protoplasm; others stressed the existence of organic and psychological individuality in protozoa. In the following decades, leading philosophers such as Friedrich Nietzsche, Charles Sanders Peirce, and Henri Bergson, as well as psychological researchers like Sigmund Freud, integrated the results of these investigations into their reflections on such problems as the nature of the will, the structure of the ego, and the holistic nature of the reactions of organisms to their environment.

  7. A k-space method for moderately nonlinear wave propagation.

    PubMed

    Jing, Yun; Wang, Tianren; Clement, Greg T

    2012-08-01

    A k-space method for moderately nonlinear wave propagation in absorptive media is presented. The Westervelt equation is first transferred into k-space via Fourier transformation, and is solved by a modified wave-vector time-domain scheme. The present approach is not limited to forward propagation or parabolic approximation. One- and two-dimensional problems are investigated to verify the method by comparing results to analytic solutions and finite-difference time-domain (FDTD) method. It is found that to obtain accurate results in homogeneous media, the grid size can be as little as two points per wavelength, and for a moderately nonlinear problem, the Courant-Friedrichs-Lewy number can be as large as 0.4. Through comparisons with the conventional FDTD method, the k-space method for nonlinear wave propagation is shown here to be computationally more efficient and accurate. The k-space method is then employed to study three-dimensional nonlinear wave propagation through the skull, which shows that a relatively accurate focusing can be achieved in the brain at a high frequency by sending a low frequency from the transducer. Finally, implementations of the k-space method using a single graphics processing unit shows that it required about one-seventh the computation time of a single-core CPU calculation.

  8. The learning type makes the difference – the interrelation of Kolb's learning styles and psychological status of preclinical medical students at the University of Erlangen

    PubMed Central

    Burger, Pascal H.; Scholz, Michael

    2014-01-01

    Theories on learning styles and types have been integral to discussions on the basics of teaching for nearly 40 years. The learning style typology of Kolb divides learners into four groups (Diverger, Assimilator, Converger and Accomodator), which differ both in terms of their learning behaviour as well as personality and preferences. We studied the sense of coherence and burnout symptoms in medical students of the preclinical semesters (1st to 4th semester) at the Friedrich-Alexander University of Erlangen within the context of the observed learning styles. A total of 530 students were interviewed in winter semester 2012/13 using standardized psychometric questionnaires. Our students showed a significant correlation between the respective learning styles and expression of a sense of coherence, as well as cognitive and emotional burnout symptoms. The learning styles of the students differed significantly within these same parameters. We also demonstrated that learning styles and types not only influence study performance, but that there are also relationships to sense of coherence and psychological ailments. A more forward-looking integration of the theory of learning types in the medical education curriculum could positively influence both the performance and psychological well-being of the students. PMID:25489342

  9. [Famous cases for amputation].

    PubMed

    Klimpel, Volker

    2004-01-01

    After a short historical survey 14 cases of celebrated personalities one woman and 13 men, with the grave handicap of amputation are represented. The causes of the lost limbs, once of the nose, were battle injuries (guns) or accidents. In many cases the protheseology followed the amputation, dependent on the technological level of the day. Often medical providing was bad and terrible. The introduction of anaesthesia changed the amputation technique. During different periods from renaissance to the first half of the twentieth century remarkable fates happened. Heroes as the emperor Friedrich III., the knight Goetz von Berlichingen, well known by the spectacle of Goethe, the scientist Tycho Brahe, the merchant and skipper Peter Stuyvesant, the military men Duke Christian II. of Braunschweig-Lueneburg-Wolfenbuettel, William Bayly, Admiral Lord Nelson and Earl Claus Stauffenberg, the actress Sarah Bernhard, the squadron leader of RAF Douglas R. S. Bader and other gave an excellent example for fulfilled life despite handicap. With their artificial legs, arms or hands they rode, fought, shoot, made sports etc.

  10. ["Fabulous things". Drug narratives about coca and cocaine in the 19th century].

    PubMed

    Wahrig, Bettina

    2009-12-01

    This contribution focuses on the history of Coca leaves and Cocaine in the second half of 19th century Europe. Even though, to date, no direct link has been established between the activities of the Milano physician Paolo Mantegazza, and the Göttingen chemist Friedrich Wöhler, it is not a mere coincidence that both published their findings in the same year, namely, 1859. Mantegazza authored the first treatise claiming that Coca had psychoactive qualities and touted its broad therapeutic faculties; he claimed that it should be introduced into European pharmacotherapy. In Wöhler's laboratory, cocaine was isolated from leaves by his pupil Alfred Niemann; later, Wilhelm Lossen refined and corrected Niemann's results. Narratives about medicinal drugs often streamline history into a story that starts with multiple meanings and impure matters and ends with well-defined substances, directed at clear-cut diseases and symptoms. In the case of Coca, however, the pure substance triggered no such process well into the 1880s, whereas the leaves continued to circulate as an exotic, pluripotent drug whose effects where miraculous and yet difficult to establish. PMID:20481059

  11. Pharmacodynamic principles of homeopathy.

    PubMed

    Widakowich, J

    2000-05-01

    Homeopathy was already known to Hippocrates and further studied by Hahnemann. However, since the discovery of the medical effects of digitalis by William Withering around 1785, and the first synthesis of an organic molecule, urea, by Friedrich Wöhler in 1828, and through the further rapid evolution of modern pharmacological chemistry and molecular biology, it has gradually been abandoned as a serious therapeutic alternative to allopathy by most practitioners of scientifically founded medicine. Because a credible scientific explanation for its mode of action has been lacking, homeopathy is regarded by many medical researchers and scientists as, at best, placebo therapy, in spite of the fact that for centuries hosts of patients have testified to its effects. It is suggested that the gulf between homeopathy and allopathy can be reconciled if one takes into consideration modern knowledge of physiology, biochemistry and the physical properties of the water used in the potentiation process. A description of the mechanisms occurring during potentiation, both inside and outside a live mammalian organism, is presented. PMID:10859675

  12. [Medicine and chemistry around the middle of the 19th century in Erlangen. Eugen Franz Freiherr von Gorup-Besanez (1817--1878) (author's transl)].

    PubMed

    Simmer, H H

    1981-07-01

    Eugen Franz Freiherr von Gorup-Besanez, born 1817 in Graz, was appointed on 28. 11. 1846 to the post of lecturer in the faculty of medicine of the University of Erlangen. He had previously studied medicine in Vienna, Padua and Munich, followed by physiological and clinical-chemical studies under Louis Andreas Buchner in Munich, and further studies in organic and analytical chemistry under Friedrich Wöhler in Göttingen. In 1849 in Erlangen he became reader in organic and analytical chemistry, then, in 1855, moved to the faculty of philosophy as professor of chemistry. Von Gorup-Besanez was one of the early representatives of clinical chemistry in Germany. He tried to help clinicians by the analysis of urine, blood and tissues. In his lectures and through his books he was an outstanding teacher. His greatest contribution was the discovery of the amino acid valine. The lack of a laboratory in the medical faculty and his dissatisfaction with what could be achieved in clinical chemistry at that time may chiefly explain his move from the medical to the philosophical faculty. The life of von Gorup-Besanez illustrates the difficulties faced by clinical chemistry and its exponents in the middle of the 19th century. PMID:7035607

  13. Discovery and development of x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Jeong, Yeuncheol; Yin, Ming; Datta, Timir

    2013-03-01

    In 1912 Max Laue at University of Munich reasoned x-rays to be short wavelength electromagnetic waves and figured interference would occur when scattered off crystals. Arnold Sommerfeld, W. Wien, Ewald and others, raised objections to Laue's idea, but soon Walter Friedrich succeeded in recording x-ray interference patterns off copper sulfate crystals. But the Laue-Ewald's 3-dimensional formula predicted excess spots. Fewer spots were observed. William Lawrence Bragg then 22 year old studying at Cambridge University heard the Munich results from father William Henry Brag, physics professor at Univ of Leeds. Lawrence figured the spots are 2-d interference of x-ray wavelets reflecting off successive atomic planes and derived a simple eponymous equation, the Bragg equation d*sin(theta) = n*lamda. 1913 onward the Braggs dominated the crystallography. Max Laue was awarded the physics Nobel in 1914 and the Braggs shared the same in 1915. Starting with Rontgen's first ever prize in 1901, the importance of x-ray techniques is evident from the four out of a total 16 physics Nobels between 1901-1917. We will outline the historical back ground and importance of x-ray diffraction giving rise to techniques that even in 2013, remain work horses in laboratories all over the globe.

  14. Complete genome sequence of Syntrophobotulus glycolicus type strain (FlGlyRT)

    SciTech Connect

    Han, Cliff; Mwirichia, Romano; Chertkov, Olga; Held, Brittany; Lapidus, Alla L.; Nolan, Matt; Lucas, Susan; Hammon, Nancy; Deshpande, Shweta; Cheng, Jan-Fang; Tapia, Roxanne; Goodwin, Lynne A.; Pitluck, Sam; Huntemann, Marcel; Liolios, Konstantinos; Ivanova, N; Pagani, Ioanna; Mavromatis, K; Ovchinnikova, Galina; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam L; Hauser, Loren John; Brambilla, Evelyne-Marie; Rohde, Manfred; Spring, Stefan; Sikorski, Johannes; Goker, Markus; Woyke, Tanja; Bristow, James; Eisen, Jonathan; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C; Klenk, Hans-Peter; Detter, J. Chris

    2011-01-01

    Syntrophobotulus glycolicus Friedrich et al. 1996 is currently the only member of the genus Syntrophobotulus within the family Peptococcaceae. The species is of interest because of its isolated phylogenetic location in the genome-sequenced fraction of tree of life. When grown in pure culture with glyoxylate as carbon source the organism utilizes glyoxylate through fermentative oxidation, whereas, when grown in syntrophic co-culture with homoacetogenic or methanogenic bacteria, it is able to oxidize glycolate to carbon dioxide and hydrogen. No other organic or inorganic carbon source is utilized by S. glycolicus. The subdivision of the family Peptococcaceae into genera does not reflect the natural relationships, particularly re- garding the genera most closely related to Syntrophobotulus. Both Desulfotomaculum and Pelotomaculum are paraphyletic assemblages, and the taxonomic classification is in signifi- cant conflict with the 16S rRNA data. S. glycolicus is already the ninth member of the family Peptococcaceae with a completely sequenced and publicly available genome. The 3,406,739 bp long genome with its 3,370 protein-coding and 69 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  15. Littre hernia: surgical anatomy, embryology, and technique of repair.

    PubMed

    Skandalakis, Panagiotis N; Zoras, Odyseas; Skandalakis, John E; Mirilas, Petros

    2006-03-01

    Littre hernia is the protrusion of a Meckel diverticulum through a potential abdominal opening. Alexis de Littre (1700) reported ileal diverticula and attributed them to traction. August Gottlieb Richter (1785) defined them as preformed, and Johann Friedrich Meckel (1809) postulated their embryologic origin. Sir Frederic Treves (1897) distinguished between Littre and Richter hernia (partial enterocele). Embryologically, Meckel diverticulum is the persistent intestinal part of the omphaloenteric duct through which the midgut communicates with the umbilical vesicle until the fifth week. It is found at the antimesenteric border of the ileum, usually located 30 to 90 cm from the ileocecal valve, measuring 3 to 6 cm in length and 2 cm in diameter. Usual sites of Littre hernia are: inguinal (50%), umbilical (20%), and femoral (20%). Meckel diverticulum may be accompanied in the sac by the ileal loop to which it is attached; rarely, it may undergo incarceration or strangulation, necrosis, and perforation. In children, it is mostly found in umbilical hernias, and the diverticulum is more prone to adhere to the sac. Repair of Littre hernia consists of resection of the diverticulum and herniorraphy; in perforated cases, care must be taken to not contaminate the hernia field.

  16. [Evaluation of a face model for surgical education].

    PubMed

    Schneider, G; Voigt, S; Rettinger, G

    2011-09-01

    The complex anatomy of the human face requires a high degree of experience and skills in surgical dressing of facial soft tissue defects. The previous education contains literature studies and supervision during surgery, according to surgical spectrum of the educating hospital. A structured education including a training of different surgical methods on a model and slow increase of complexity could improve considerably the following education related to the patient.During a cooperative project, the 3 di GmbH and the Department of Otolaryngology at the Friedrich-Schiller-University Jena developed a face model for surgical education that allows the training of surgical interventions in the face. The model was used during the 6th and 8th Jena Workshop for Functional and Aesthetic Surgery as well as a workshop for surgical suturation, and tested and evaluated by the attendees.The attendees mostly rated the work-ability of the models and the possibility to practice on a realistic face model with artificial skin very well and beneficial. This model allows a repeatable and structured education of surgical standards, and is very helpful in preparation for operating facial defects of a patient.

  17. Direct Replacement of Arbitrary Grid-Overlapping by Non-Structured Grid

    NASA Technical Reports Server (NTRS)

    Kao, Kai-Hsiung; Liou, Meng-Sing

    1994-01-01

    A new approach that uses nonstructured mesh to replace the arbitrarily overlapped structured regions of embedded grids is presented. The present methodology uses the Chimera composite overlapping mesh system so that the physical domain of the flowfield is subdivided into regions which can accommodate easily-generated grid for complex configuration. In addition, a Delaunay triangulation technique generates nonstructured triangular mesh which wraps over the interconnecting region of embedded grids. It is designed that the present approach, termed DRAGON grid, has three important advantages: eliminating some difficulties of the Chimera scheme, such as the orphan points and/or bad quality of interpolation stencils; making grid communication in a fully conservative way; and implementation into three dimensions is straightforward. A computer code based on a time accurate, finite volume, high resolution scheme for solving the compressible Navier-Stokes equations has been further developed to include both the Chimera overset grid and the nonstructured mesh schemes. For steady state problems, the local time stepping accelerates convergence based on a Courant - Friedrichs - Leury (CFL) number near the local stability limit. Numerical tests on representative steady and unsteady supersonic inviscid flows with strong shock waves are demonstrated.

  18. PubMed

    Möstl, Ute V; Erkaev, Nikolay V; Zellinger, Michael; Lammer, Helmut; Gröller, Hannes; Biernat, Helfried K; Korovinskiy, Daniil

    2011-12-01

    The Kelvin-Helmholtz instability gained scientific attention after observations at Venus by the spacecraft Pioneer Venus Orbiter gave rise to speculations that the instability contributes to the loss of planetary ions through the formation of plasma clouds. Since then, a handful of studies were devoted to the Kelvin-Helmholtz instability at the ionopause and its implications for Venus. The aim of this study is to investigate the stability of the two instability-relevant boundary layers around Venus: the induced magnetopause and the ionopause. We solve the 2D magnetohydrodynamic equations with the total variation diminishing Lax-Friedrichs algorithm and perform simulation runs with different initial conditions representing the situation at the boundary layers around Venus. Our results show that the Kelvin-Helmholtz instability does not seem to be able to reach its nonlinear vortex phase at the ionopause due to the very effective stabilizing effect of a large density jump across this boundary layer. This seems also to be true for the induced magnetopause for low solar activity. During high solar activity, however, there could occur conditions at the induced magnetopause which are in favour of the nonlinear evolution of the instability. For this situation, we estimated roughly a growth rate for planetary oxygen ions of about 7.6 × 10(25) s(-1), which should be regarded as an upper limit for loss due to the Kelvin-Helmholtz instability.

  19. [The Essen-based steel producer Alfred Krupp (1812-1887) as a reader of the flora and fauna of the Gulf of Naples. A look at the relationship of Anton Dohrn (1840-1909) to the house Krupp].

    PubMed

    Müller, Irmgard

    2015-01-01

    A unfavourable notice written by industrial magnate Alfred Krupp (1812-1887) has been discovered on the posterior cover sheet of the first volume of the monumental series Fauna und Flora des Golfes von Neapel, edited by the Zoological Station at Naples (1880) Krupp's handwritten statement affords the opportunity to discuss in more detail the intricate relationship between the founder of the first marine biology station, Anton Dohrn (1840-1909), and the owner of the greatest steel factory in Europe, the Krupp-family at Essen. Although Anton Dohrn did not know about Krupp's disapproving comment he had a fine unerring instinct for the mentality of his negotiating partner, whose way of thinking rather aimed at the practical success and completion of armament factory, preventing thus a the serious rapprochement between the two personalities. Even when the Krupp-heir, Friedrich Alfred Krupp, later devoted to questions about marine biology in his new built house at Capri, and was willing to support the Zoological Station with high sponsoring, Anton Dohrn maintained a reserved attitude towards the Krupp's offer to support the marine research financially. Likewise, he remained unimpressed, when the steel magnate was shook by the smear campaign in Capri that ultimately led to Krupp's death in November 1902. PMID:25515144

  20. High-order accurate physical-constraints-preserving finite difference WENO schemes for special relativistic hydrodynamics

    NASA Astrophysics Data System (ADS)

    Wu, Kailiang; Tang, Huazhong

    2015-10-01

    The paper develops high-order accurate physical-constraints-preserving finite difference WENO schemes for special relativistic hydrodynamical (RHD) equations, built on the local Lax-Friedrichs splitting, the WENO reconstruction, the physical-constraints-preserving flux limiter, and the high-order strong stability preserving time discretization. They are extensions of the positivity-preserving finite difference WENO schemes for the non-relativistic Euler equations [20]. However, developing physical-constraints-preserving methods for the RHD system becomes much more difficult than the non-relativistic case because of the strongly coupling between the RHD equations, no explicit formulas of the primitive variables and the flux vectors with respect to the conservative vector, and one more physical constraint for the fluid velocity in addition to the positivity of the rest-mass density and the pressure. The key is to prove the convexity and other properties of the admissible state set and discover a concave function with respect to the conservative vector instead of the pressure which is an important ingredient to enforce the positivity-preserving property for the non-relativistic case. Several one- and two-dimensional numerical examples are used to demonstrate accuracy, robustness, and effectiveness of the proposed physical-constraints-preserving schemes in solving RHD problems with large Lorentz factor, or strong discontinuities, or low rest-mass density or pressure etc.

  1. A semi-implicit gas-kinetic scheme for smooth flows

    NASA Astrophysics Data System (ADS)

    Wang, Peng; Guo, Zhaoli

    2016-08-01

    In this paper, a semi-implicit gas-kinetic scheme (SIGKS) is derived for smooth flows based on the Bhatnagar-Gross-Krook (BGK) equation. As a finite-volume scheme, the evolution of the average flow variables in a control volume is under the Eulerian framework, whereas the construction of the numerical flux across the cell interface comes from the Lagrangian perspective. The adoption of the Lagrangian aspect makes the collision and the transport mechanisms intrinsically coupled together in the flux evaluation. As a result, the time step size is independent of the particle collision time and solely determined by the Courant-Friedrichs-Lewy (CFL) condition. An analysis of the reconstructed distribution function at the cell interface shows that the SIGKS can be viewed as a modified Lax-Wendroff type scheme with an additional term. Furthermore, the addition term coming from the implicitness in the reconstruction is expected to be able to enhance the numerical stability of the scheme. A number of numerical tests of smooth flows with low and moderate Mach numbers are performed to benchmark the SIGKS. The results show that the method has second-order spatial accuracy, and can give accurate numerical solutions in comparison with benchmark results. It is also demonstrated that the numerical stability of the proposed scheme is better than the original GKS for smooth flows.

  2. Phase transitions in nonequilibrium traffic theory

    SciTech Connect

    Zhang, H.M.

    2000-02-01

    This paper uses the center difference scheme of Lax-Friedrichs to numerically solve a newly developed continuum traffic flow theory and the kinematic theory of Lighthill and Whitham, and Richards, and it studies the flow-concentration phase transitions in flow containing both shock and rarefaction waves. A homogeneous road with finite length was modeled by both theories. Numerical simulations show that both theories yield nearly identical results for two representative Riemann problems--one has a shock solution and the other a rarefaction wave solution. Their phase transition curves, however, are different: those derived from the new theory have two branches--one for acceleration flow and one for deceleration flow, whereas those derived from the LWR theory comprise a single curve--the equilibrium curve. The phase transition curves in the shock case agree well with certain experimental observations but disagree with others. This disagreement may be resolved by studying transitions among nonequilibrium states, which awaits further development of a more accurate finite difference approximation of the nonequilibrium theory.

  3. Theoretical study of the incompressible Navier-Stokes equations by the least-squares method

    NASA Technical Reports Server (NTRS)

    Jiang, Bo-Nan; Loh, Ching Y.; Povinelli, Louis A.

    1994-01-01

    Usually the theoretical analysis of the Navier-Stokes equations is conducted via the Galerkin method which leads to difficult saddle-point problems. This paper demonstrates that the least-squares method is a useful alternative tool for the theoretical study of partial differential equations since it leads to minimization problems which can often be treated by an elementary technique. The principal part of the Navier-Stokes equations in the first-order velocity-pressure-vorticity formulation consists of two div-curl systems, so the three-dimensional div-curl system is thoroughly studied at first. By introducing a dummy variable and by using the least-squares method, this paper shows that the div-curl system is properly determined and elliptic, and has a unique solution. The same technique then is employed to prove that the Stokes equations are properly determined and elliptic, and that four boundary conditions on a fixed boundary are required for three-dimensional problems. This paper also shows that under four combinations of non-standard boundary conditions the solution of the Stokes equations is unique. This paper emphasizes the application of the least-squares method and the div-curl method to derive a high-order version of differential equations and additional boundary conditions. In this paper, an elementary method (integration by parts) is used to prove Friedrichs' inequalities related to the div and curl operators which play an essential role in the analysis.

  4. Classical swine fever virus detection: results of a real-time reverse transcription polymerase chain reaction ring trial conducted in the framework of the European network of excellence for epizootic disease diagnosis and control.

    PubMed

    Hoffmann, Bernd; Blome, Sandra; Bonilauri, Paolo; Fernández-Piñero, Jovita; Greiser-Wilke, Irene; Haegeman, Andy; Isaksson, Mats; Koenen, Frank; LeBlanc, Neil; Leifer, Immanuel; Le Potier, Marie-Frederique; Loeffen, Willie; Rasmussen, Thomas Bruun; Stadejek, Tomasz; Ståhl, Karl; Tignon, Marylène; Uttenthal, Ase; van der Poel, Wim; Beer, Martin

    2011-09-01

    The current study reports on a real-time reverse transcription polymerase chain reaction (real-time RT-PCR) ring trial for the detection of Classical swine fever virus (CSFV) genomic RNA undertaken by 10 European laboratories. All laboratories were asked to use their routine in-house real-time RT-PCR protocols and a standardized protocol commonly used by the Friedrich-Loeffler-Institute (FLI) on a panel of well-characterized samples. In general, all participants produced results within the acceptable range. The FLI assay, several in-house assays, and the commercial kits had high analytical sensitivity and specificity values. Nevertheless, some in-house systems had unspecific reactions or suboptimal sensitivity with only a single CSFV genotype. Follow-up actions involved either improvement of suboptimal assays or replacement of specific laboratory assays with the FLI protocol, with or without modifications. In conclusion, the ring trial showed reliability of classical swine fever diagnosis on an international level and helped to optimize CSFV-specific RT-PCR diagnostics.

  5. Modeling Urban Flood Dynamics Using High-Resolution Topography and Bathymetry

    NASA Astrophysics Data System (ADS)

    Dwelle, M. C.; Kim, J.; Ivanov, V. Y.

    2015-12-01

    Flooding is the leading cause of death from natural disasters and poses public health and economic risks to developed and developing cities. In order to better assess these risks, models of flooding need to rely on modern, up-to-date information about urban environments. Approaches based on traditional grids are computationally expensive because of the restriction of the Courant-Friedrichs-Levy condition. This condition introduces a resolution dependency into hydrodynamic models, affecting a number of states such as velocity and water depth, and therefore may impact management and design decisions, becoming a serious weakness in real-time situations.This research links watershed processes to the urban environment by applying an upscaling method that relies on fine-scale information on elevation, roughness, land cover, and soil moisture. The benefit of this approach is that it reduces resolution dependency, allowing for the calculation of hydrodynamic variables at subgrid scales. This approach negates the need for grid refinement in complex geometries and surface conditions of the urban interface, improving the computational efficiency for simulating and predicting flooding events.

  6. Forensic psychiatry in nineteenth-century Saxony: the case of Woyzeck.

    PubMed

    Steinberg, Holger; Schmidt-Recla, Adrian; Schmideler, Sebastian

    2007-01-01

    In contrast to other areas of psychiatry, little work has been done on the history of forensic psychiatry, and such work is especially scarce regarding the first half of the 19th century, when forensic psychiatry began to develop together with the neurosciences. One newly discovered archival source bears immediate witness to the genesis of forensic psychiatry and is presented for the first time in this study. That source helps us to better understand, in particular, one of the most important cases in 19th-century German forensic psychiatry - namely, that of Johann Christian Woyzeck, the murderer who became the lead figure and the decisive model for the famous eponymous drama by German poet Georg Büchner. Duke Friedrich August, the heir to the throne of the German kingdom of Saxony, submitted a separately recorded special vote (or, very roughly speaking, a brief) that denied the criminal responsibility of the murderer since he had committed his crime out of jealousy and in an emotionally agitated state of mind that eliminated the offender's free will. Though possessing no relevant professional training, the duke applied, and argued in support of, a syndrome - partial mania - that was then the subject of ongoing controversy in general psychiatry. In that context, his vote and analysis can be seen a part of the conceptual development not only of forensic psychiatry, but also of German psychiatry and criminal law.

  7. 'Struensee's memoir on the situation of the King' (1772): Christian VII of Denmark.

    PubMed

    Schioldann, Johan

    2013-06-01

    Christian VII of Denmark (1749-1808) was insane throughout his long reign. The royal physician, Johann Friedrich Struensée (1737-72), usurped his power. In 1771 the King appointed him Privy Cabinet Minister. Struensée revolutionized the whole administration of the Danish-Norwegian kingdom and had an adulterous relationship with the Queen, Caroline Mathilda, George III's sister. In January 1772 he was arrested, sentenced to death for lese-majesty and executed. During his confinement, he wrote a memoir on the King's condition, which he considered to be caused by, or the effect of, masturbation. In 1906 Christiansen interpreted it as a case of dementia praecox, i.e. schizophrenia. It is now suggested that Christian's insanity, like that of George III (his cousin), might have been due to porphyria - the 'royal malady', possibly inherited through his mother, Princess Louise of England or his father, King Frederik V, who died from an illness which retrospectively resembles a case of porphyria.

  8. High order Godunov mixed methods on tetrahedral meshes for density driven flow simulations in porous media

    NASA Astrophysics Data System (ADS)

    Mazzia, Annamaria; Putti, Mario

    2005-09-01

    Two-dimensional Godunov mixed methods have been shown to be effective for the numerical solution of density-dependent flow and transport problems in groundwater even when concentration gradients are high and the process is dominated by density effects. This class of discretization approaches solves the flow equation by means of the mixed finite element method, thus guaranteeing mass conserving velocity fields, and discretizes the transport equation by mixed finite element and finite volumes techniques combined together via appropriate time splitting. In this paper, we extend this approach to three dimensions employing tetrahedral meshes and introduce a spatially variable time stepping procedure that improves computational efficiency while preserving accuracy by adapting the time step size according to the local Courant-Friedrichs-Lewy (CFL) constraint. Careful attention is devoted to the choice of a truly three-dimensional limiter for the advection equation in the time-splitting technique, so that to preserve second order accuracy in space (in the sense that linear functions are exactly interpolated). The three-dimensional Elder problem and the saltpool problem, recently introduced as a new benchmark for testing three-dimensional density models, provide assessments with respect to accuracy and reliability of this numerical approach.

  9. Computational techniques for high-speed flows with viscous and chemical effects

    NASA Technical Reports Server (NTRS)

    Li, C. P.

    1993-01-01

    Algorithms for solving the Euler and the Navier-Stokes equations in conjunction with chemical kinetic equations are presented. The convective flux is estimated from a quasi one dimensional interpolation procedure. Shock, contact, and expansion waves and thermochemical nonequilibrium phenomena are captured by the Lax-Friedrichs technique. Relaxation techniques were developed to enhance their effectiveness in dealing with spatial and temporal stiffness associated with the physical problems. Both explicit and implicit smoothers were implemented into the standard multigrid time stepping method. Unsteady and steady scalar problems are discussed. A perfect gas and equilibrium air shock tube problem is investigated. Numerical schemes and techniques are compared for the problems of shock and boundary layer interaction and three dimensional viscous, nonequilibrium flow encompassing an aerobrake. The results are comparable in accuracy against other high order non-oscillatory techniques. The multigrid methods are assessed using a Mach 8 flow over a complete planar body, a sphere, and a blunt delta wing at 20 deg incidence. Applying an implicit multigrid method on a nested grid of 128 by 64 nodes the reduction factor is 0.25. The central processing unit reduction factor is 2.2 after both the single and multigrid Runge-Kutta solutions converged to machine zero on a grid of 37 by 41 by 73 nodes.

  10. A high order characteristic discontinuous Galerkin scheme for advection on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Lee, D.; Lowrie, R.; Petersen, M.; Ringler, T.; Hecht, M.

    2016-11-01

    A new characteristic discontinuous Galerkin (CDG) advection scheme is presented. In contrast to standard discontinuous Galerkin schemes, the test functions themselves follow characteristics in order to ensure conservation and the edges of each element are also traced backwards along characteristics in order to create a swept region, which is integrated in order to determine the mass flux across the edge. Both the accuracy and performance of the scheme are greatly improved by the use of large Courant-Friedrichs-Lewy numbers for a shear flow test case and the scheme is shown to scale sublinearly with the number of tracers being advected, outperforming a standard flux corrected transport scheme for 10 or more tracers with a linear basis. Moreover the CDG scheme may be run to arbitrarily high order spatial accuracy and on unstructured grids, and is shown to give the correct order of error convergence for piecewise linear and quadratic bases on regular quadrilateral and hexahedral planar grids. Using a modal Taylor series basis, the scheme may be made monotone while preserving conservation with the use of a standard slope limiter, although this reduces the formal accuracy of the scheme to first order. The second order scheme is roughly as accurate as the incremental remap scheme with nonlocal gradient reconstruction at half the horizontal resolution. The scheme is being developed for implementation within the Model for Prediction Across Scales (MPAS) Ocean model, an unstructured grid finite volume ocean model.

  11. On Accuracy of Adaptive Grid Methods for Captured Shocks

    NASA Technical Reports Server (NTRS)

    Yamaleev, Nail K.; Carpenter, Mark H.

    2002-01-01

    The accuracy of two grid adaptation strategies, grid redistribution and local grid refinement, is examined by solving the 2-D Euler equations for the supersonic steady flow around a cylinder. Second- and fourth-order linear finite difference shock-capturing schemes, based on the Lax-Friedrichs flux splitting, are used to discretize the governing equations. The grid refinement study shows that for the second-order scheme, neither grid adaptation strategy improves the numerical solution accuracy compared to that calculated on a uniform grid with the same number of grid points. For the fourth-order scheme, the dominant first-order error component is reduced by the grid adaptation, while the design-order error component drastically increases because of the grid nonuniformity. As a result, both grid adaptation techniques improve the numerical solution accuracy only on the coarsest mesh or on very fine grids that are seldom found in practical applications because of the computational cost involved. Similar error behavior has been obtained for the pressure integral across the shock. A simple analysis shows that both grid adaptation strategies are not without penalties in the numerical solution accuracy. Based on these results, a new grid adaptation criterion for captured shocks is proposed.

  12. Time-stepping stability of continuous and discontinuous finite-element methods for 3-D wave propagation

    NASA Astrophysics Data System (ADS)

    Mulder, W. A.; Zhebel, E.; Minisini, S.

    2014-02-01

    We analyse the time-stepping stability for the 3-D acoustic wave equation, discretized on tetrahedral meshes. Two types of methods are considered: mass-lumped continuous finite elements and the symmetric interior-penalty discontinuous Galerkin method. Combining the spatial discretization with the leap-frog time-stepping scheme, which is second-order accurate and conditionally stable, leads to a fully explicit scheme. We provide estimates of its stability limit for simple cases, namely, the reference element with Neumann boundary conditions, its distorted version of arbitrary shape, the unit cube that can be partitioned into six tetrahedra with periodic boundary conditions and its distortions. The Courant-Friedrichs-Lewy stability limit contains an element diameter for which we considered different options. The one based on the sum of the eigenvalues of the spatial operator for the first-degree mass-lumped element gives the best results. It resembles the diameter of the inscribed sphere but is slightly easier to compute. The stability estimates show that the mass-lumped continuous and the discontinuous Galerkin finite elements of degree 2 have comparable stability conditions, whereas the mass-lumped elements of degree one and three allow for larger time steps.

  13. [Weizsäcker's cosmogony, Farm Hall and the origin of modern turbulence theory].

    PubMed

    Eckert, Michael

    2014-01-01

    The modem statistical theory of turbulence was originated by Andrey Nikolaevich Kolmogorov (1903-1987), Lars Onsager (1903-1976), Ludwig Prandtl (1875-1953), Werner Heisenberg (1901-1976) und Carl Friedrich von Weizsäcker (1912-2007). With the exception of Kolmogorovs theory which was published in 1941 but became widely known only after the war, these contributions emerged largely independently from another in a "remarkable series of coincidences" (Batchelor 1946). Heisenberg and Weizäscker developed their theories during their detention at Farm Hall. Their work was motivated by von Weizsäcker's interest in astrophysics. Weizsäcker aimed at an understanding of the role of turbulence for the motion of interstellar matter for his theory about the origin of the planetary system which he had published in 1943. Weizsäcker's work on cosmogony and turbulence illustrates an early interaction between the disciplines of astronomy and fluid mechanics that became characteristic for astrophysics in the second half of the twentieth century. PMID:24974597

  14. Pulmonary Alveolar Microlithiasis “Stone Lungs”: A Case of Clinico-Radiological Dissociation

    PubMed Central

    Shaharyar, Sameer; Chokshi, Binna; Bhardwaj, Nikhil

    2016-01-01

    Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by deposition of spherical calcium phosphate microliths called calcospherites within the alveoli. PAM was first described by Friedrich in 1856 and then by Harbitz in 1918. The disease pathogenesis is based on mutations in the SLC34A2 gene that encodes for the Type IIb sodium-phosphate cotransporter. The majority of the patients are diagnosed at an early age, usually between the ages of 20 and 40 years. The hallmark of this disease is a striking dissociation between the radiological findings and the mild clinical symptoms.  We report a case of 35-year-old woman who presented post-motor vehicle accident with back pain and with minimal dyspnea on exertion. The final diagnosis was made after computed tomography and lung biopsy. The present case exhibits the remarkable clinico-radiological dissociation with complete calcification of the lungs on radiographic images with a relatively mild clinical presentation. PMID:27688986

  15. A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS

    SciTech Connect

    Takahashi, Hiroyuki R.; Ohsuga, Ken

    2013-08-01

    We develop a numerical scheme for solving fully special relativistic, resistive radiation magnetohydrodynamics. Our code guarantees conservation of total mass, momentum, and energy. The radiation energy density and the radiation flux are consistently updated using the M-1 closure method, which can resolve an anisotropic radiation field, in contrast to the Eddington approximation, as well as the flux-limited diffusion approximation. For the resistive part, we adopt a simple form of Ohm's law. The advection terms are explicitly solved with an approximate Riemann solver, mainly the Harten-Lax-van Leer scheme; the HLLC and HLLD schemes are also solved for some tests. The source terms, which describe the gas-radiation interaction and the magnetic energy dissipation, are implicitly integrated, relaxing the Courant-Friedrichs-Lewy condition even in an optically thick regime or a large magnetic Reynolds number regime. Although we need to invert 4 Multiplication-Sign 4 matrices (for the gas-radiation interaction) and 3 Multiplication-Sign 3 matrices (for the magnetic energy dissipation) at each grid point for implicit integration, they are obtained analytically without preventing massive parallel computing. We show that our code gives reasonable outcomes in numerical tests for ideal magnetohydrodynamics, propagating radiation, and radiation hydrodynamics. We also applied our resistive code to the relativistic Petschek-type magnetic reconnection, revealing the reduction of the reconnection rate via radiation drag.

  16. Schumann's wheel tachistoscope: its reconstruction and its operation.

    PubMed

    Stock, Armin

    2014-05-01

    In the fall and winter of 1910, Max Wertheimer (1880-1943) performed his famous experiments on perceived motion, published in 1912. Besides slider experiments he mainly used a wheel tachistoscope developed by Friedrich Schumann (1863-1940) at the end of the 19th century. The Adolf-Wuerth-Center for the History of Psychology has several wheel tachistoscopes in its collection of instruments. Their provenance can be traced back to the Institute of Psychology of the University of Frankfurt and the University of Zurich. It is very plausible that Wertheimer, who performed his experiments at the Frankfurt Institute, used one of them. But the wheel tachistoscope alone is not sufficient to reconstruct Wertheimer's original experiments. As always, the devil is in the details. Wertheimer's descriptions of the necessary accessories, a prism, a viewing device, and an electric motor to move the wheel, are rather sparse. This article describes the results of a search for traces in the literature, in archives, and in literary depositories to shed some light on Wertheimer's experimental equipment. As a result, it was possible to reconstruct the entire apparatus and to obtain the same optical impressions with the reconstructed devices as Wertheimer's observers reported. In addition, one of his results was replicated with new participants exactly 100 years after its first publication. PMID:24818744

  17. Early American Strabismus Surgery: 1840-1845.

    PubMed

    Currie, Benjamin D; Feibel, Robert M

    2015-01-01

    The discovery of effective surgical therapy for strabismus was one of the outstanding triumphs of the first half of 19th-century ophthalmology, just prior to the invention of the ophthalmoscope in 1850. Although priority for the development of strabismus surgery belongs to Johann Friedrich Dieffenbach of Germany, who first reported his surgical results in 1839, 4 cases of tenotomy of the medial rectus muscle had been performed in the United States by William Gibson in 1818 but never published. By 1840, the reports of surgery in Europe had rapidly spread to America where surgeons immediately began using these procedures. The first American surgeon to perform eye muscle surgery and publish his results was John Dix of Boston, and other surgeons were soon reporting their cases as well. We discuss 8 American pioneers in this field during the time (1840-1845) of the first burst of enthusiasm for this surgery. Although these surgeons were active in performing a large number of cases and carefully reporting their experiences and results, they did not make any major advances in the field. PMID:26669424

  18. Nietzsche's aesthetic critique of Darwin.

    PubMed

    Pence, Charles H

    2011-01-01

    Despite his position as one of the first philosophers to write in the "post-Darwinian" world, the critique of Darwin by Friedrich Nietzsche is often ignored for a host of unsatisfactory reasons. I argue that Nietzsche's critique of Darwin is important to the study of both Nietzsche's and Darwin's impact on philosophy. Further, I show that the central claims of Nietzsche's critique have been broadly misunderstood. I then present a new reading of Nietzsche's core criticism of Darwin. An important part of Nietzsche's response can best be understood as an aesthetic critique of Darwin, reacting to what he saw as Darwin having drained life of an essential component of objective aesthetic value. For Nietzsche, Darwin's theory is false because it is too intellectual, because it searches for rules, regulations, and uniformity in a realm where none of these are to be found - and, moreover, where they should not be found. Such a reading goes furthest toward making Nietzsche's criticism substantive and relevant. Finally, I attempt to relate this novel explanation of Nietzsche's critique to topics in contemporary philosophy of biology, particularly work on the evolutionary explanation of culture.

  19. Friederich Nietzsche and the seduction of Occam's razor.

    PubMed

    Danesh-Meyer, Helen V; Young, Julian

    2010-08-01

    Friedrich Nietzsche developed dementia at the age of 44 years. It is generally assumed that the cause of his dementia was neurosyphilis or general pareisis of the insane (GPI). Others have proposed frontal-based meningioma as the underlying cause. We have reviewed Nietzsche's medical history and evaluated the evidence from the medical examinations he underwent by various physicians. We have viewed the possible diagnosis of GPI or meningioma in light of present neuro-ophthalmic understanding and found that Nietzsche did not have the neurological or neuro-ophthalmic symptoms consistent with a diagnosis of GPI. The anisocoria which was assumed to be Argyll Robertson pupil was present since he was six years of age. He did not have tongue tremor, lacked progressive motor features and lived at least 12 years following the onset of his neurological signs. Furthermore, the headaches that have been attributed to a frontal-based tumour were present since childhood and the pupil abnormality that has been interpreted as an "afferent pupillary defect" had the characteristics of an abnormality of the efferent pupillary innervation. None of the medical records or photographs suggest there was any ocular misalignment. We concluded that neither diagnosis of GPI nor frontal-based meningioma is convincing. It is likely that Nietzsche suffered from migraines, his blindness in his right eye was a consequence of high progressive myopia associated with retinal degeneration, his anisocoria explained by unilateral tonic pupil, and his dementia by an underlying psychiatric disease.

  20. MDLab: a molecular dynamics simulation prototyping environment.

    PubMed

    Cickovski, Trevor; Chatterjee, Santanu; Wenger, Jacob; Sweet, Christopher R; Izaguirre, Jesús A

    2010-05-01

    Molecular dynamics (MD) simulation involves solving Newton's equations of motion for a system of atoms, by calculating forces and updating atomic positions and velocities over a timestep Deltat. Despite the large amount of computing power currently available, the timescale of MD simulations is limited by both the small timestep required for propagation, and the expensive algorithm for computing pairwise forces. These issues are currently addressed through the development of efficient simulation methods, some of which make acceptable approximations and as a result can afford larger timesteps. We present MDLab, a development environment for MD simulations built with Python which facilitates prototyping, testing, and debugging of these methods. MDLab provides constructs which allow the development of propagators, force calculators, and high level sampling protocols that run several instances of molecular dynamics. For computationally demanding sampling protocols which require testing on large biomolecules, MDL includes an interface to the OpenMM libraries of Friedrichs et al. which execute on graphical processing units (GPUs) and achieve considerable speedup over execution on the CPU. As an example of an interesting high level method developed in MDLab, we present a parallel implementation of the On-The-Fly string method of Maragliano and Vanden-Eijnden. MDLab is available at http://mdlab.sourceforge.net.

  1. [Relationship between Copenhagen and Göttingen regarding earth magnetism].

    PubMed

    Reich, Karin

    2013-01-01

    Hans Christian Oersted is mostly known as the discoverer of electromagnetism and for being one of the physicists who were deeply influenced and fascinated by the romantic natural philosophy. In this article another side of Oersted is presented. What is underestimated until now is Oersted's contribution to the research of geomagnetism. Oersted stood in close contact with Carl Friedrich Gauss and Wilhelm Weber, whom he visited in 1834 in Göttingen. Oersted's aim was to learn the new developments in geomagnetism. Afterwards he was crucial in the building of a new magnetic observatory in Copenhagen as well as a second one with better equipment. Oersted formed a huge team for magnetic observations and the gathered data were sent to Gauss and Weber who published them. The correspondence between Oersted, Gauss and Weber was mostly dedicated to the transmission of these data, details about instruments and the best way of building a magnetic observatory. Unfortunately, Gauss and Weber had to stop their very successful collaboration in 1843, because Weber belonged to the Göttingen Seven and later on Oersted stopped his observations, because he had lost his partners in this research project. PMID:24195332

  2. [The history of prostate cancer from the beginning to DaVinci].

    PubMed

    Hatzinger, M; Hubmann, R; Moll, F; Sohn, M

    2012-07-01

    For hardly any other organ can the development of medicine and technical advances in the last 150 years be so clearly illustrated as for the prostate. The history of radical prostatectomy was initially characterised by the problems in approaching this relatively difficulty accessible organ. In 1867, Theodor Billroth in Vienna performed the first partial prostatectomy via a perineal access. In 1904, Hugh Hampton Young and William Stewart Halsted at the Johns Hopkins Hospital in Baltimore / USA carried out the first successful extracapsular perineal prostatectomy and opened up a new era. In Germany, Prof. Friedrich Voelcker in Halle in 1924 developed the so-called ischiorectal prostatectomy. But it was left to Terence Millin to publish in 1945 the first series of retropubic prostatectomies. In 1952, the sacroperineal approach according to Thiermann and the sacral prostatectomy according to were introduced. Finally, in 1991 another new era in prostate surgery started with the first laparoscopic prostatectomy. This development peaked in 2011 with the presentation of the laparoscopic DaVinci prostatectomy by Binder. Originally a stepchild of urological surgery that was to be avoided whenever possible due to the fear of serious complications, the prostate has progressed in the course of time to an obscure object of lust. The stepchild has become the favorite child. PMID:23035261

  3. Stability property of numerical Cherenkov radiation and its application to relativistic shock simulations

    NASA Astrophysics Data System (ADS)

    Ikeya, Naoki; Matsumoto, Yosuke

    2015-08-01

    We studied the stability property of numerical Cherenkov radiation in relativistic plasma flows employing particle-in-cell simulations. Using the implicit finite-difference time-domain method to solve the Maxwell equations, we found that nonphysical instability was greatly inhibited with a Courant-Friedrichs-Lewy (CFL) number of 1.0. The present result contrasts with recently reported results (Vay et al. 2011, J. Comp. Phys., 230, 5908; Godfrey & Vay 2013, J. Comp. Phys., 248, 33; Xu et al. 2013, Comput. Phys. Commun., 184, 2503) in which magical CFL numbers in the range 0.5-0.7 were obtained with explicit field solvers. In addition, we found employing higher-order shape functions and an optimal implicitness factor further suppressed long-wavelength modes of the instability. The findings allowed the examination of the long-term evolution of a relativistic collisionless shock without the generation of nonphysical wave excitations in the upstream. This achievement will allow us to investigate particle accelerations in relativistic shocks associated with, for example, gamma-ray bursts.

  4. From Gauß to Biermann: Highlights from the first 117 years of publications in Astronomische Nachrichten/Astronomical Notes

    NASA Astrophysics Data System (ADS)

    von Berlepsch, R.; Strassmeier, K. G.

    2009-06-01

    We present facsimiles of some of the scientifically and historically most relevant papers published in Astronomische Nachrichten/Astronomical Notes (AN) between 1821 and 1938. Almost all of these papers were written and printed in German and it is sometimes not completely straightforward to find these original works and then to cite the historically correct version, e.g. in case of a series of articles or editorial letters. It was common during the early years that many contributions were made in form of letters to the editor. We present a summary for these original works with an English translation of their titles. Among the highlights are the originals of the discovery of stellar parallaxes by Friedrich Wilhelm Bessel, the discovery of the solar cycle by Heinrich Schwabe, the discovery of the planet Neptune by Johann Gottfried Galle, the first ever measured stellar radial velocity by Hermann Vogel, the discovery of radio emission from the Sun by Wilsing and Scheiner, the first ever conducted photoelectric photometry of stars by Paul Guthnick and up to the pioneering work by Karl Schwarzschild, Ejnar Hertzsprung, Erwin Finlay Freundlich and others. As a particular gimmick we present the still world record holding shortest paper ever published; by Johannes Hartmann in AN 226, 63 (1926) on Nova Pictoris. Our focus is on contributions in the early years and published until 1938 near the verge of the second world war.

  5. [Clarification of a political assassination in 1839: statesman Johannes Hegetschweiler shot during civil unrest in Zurich].

    PubMed

    Mörgeli, C

    1992-05-26

    The death by violence of the scientist and statesman Johannes Hegetschweiler (1789-1839), M.D., constituted a double tragedy: just previously, at the instigation of his friends, he had withdrawn an already submitted petition to be relieved of all his public functions. And from the outset he declared himself an opponent to the appointment of the theologian Friedrich David Strauss to the Zurich Professorship for Dogmatics, an appointment leading to political unrest ('Züriputsch'). On September 6, 1839, Hegetschweiler dashed, as a member of the Cantonal Government, between the militia of the Government and the advancing insurrectionists with instructions to effect a cease-fire. While doing so, he was wounded in the head by a deliberately aimed discharge of a shot, succumbing after three days of suffering. The general turbulence occasioned by the Züriputsch, the unprecedented animosity among the political misdemeanors and felonies rendered any legal prosecution impossible. It is here proven that one of the insurrectionists from the Zurich Oberland is the only person who can be considered as the murderer of Hegetschweiler.

  6. Computational Modeling of Multi-Phase/Multi-Species Flows with Applications to Liquid Rocket Engines

    NASA Technical Reports Server (NTRS)

    Navaz, Homayun K.

    1996-01-01

    Accurate prediction of all physical phenomena in a combustion chamber is essential for better understanding of the system performance. Atomization, evaporation, combustion, chemical kinetics, and turbulence are those processes of great importance that need to be well understood. Processes involving the liquid phase in a combustion chamber will be further complicated under supercritical conditions. More advanced and accurate numerical techniques are required to extend our understanding of the above phenomena. A computer program for multi-species/multi-phase flow was developed for NASA/MSFC in 1992. This code, called Liquid Thrust Chamber Performance (LTCP) program takes an Eulerian- Eulerian approach and is based on the Total Variation Diminishing (TVD) technique with Lax-Friedrichs upwind method. Under the NASA/ASEE SFFP the LTCP code was used to predict the performance characteristics of several engines that were of particular interest to NASA. This code was also successful in a combustion detonation study. Converting the program to the PC platform was accomplished which extends usability and makes it available to a wider range of users. The Eulerian formulation of the liquid phase provides a suitable model that can be extended to include combustion modeling under supercritical conditions. The results have been compared against the ones of other codes and available measured data. The algorithm proved to be robust and efficient for problems with stiff source terms.

  7. Austria's Scientific Contribution to the Observation of the Venus Transit of 1874

    NASA Astrophysics Data System (ADS)

    Kopper, M.

    2004-12-01

    Already since the mid-19th century, it was a task of the Imperial-Royal Austro-Hungarian Navy not only to take part in military actions, to train sea cadets, to strengthen diplomatic relations, and to protect the coasts, the sea trade, and Austrian citizens in far countries, but also to carry out coast surveys and soundings, as well as scientific observations during their missions. On a trip around the earth, Tobias von Österreicher, commander of the corvette "Erzherzog Friedrich", was instructed to observe the Venus transit of December 8, 1874 in Yokohama. This order was only one out of many that he had to fulfill: to train the Navy cadets, to explore the possibility of the installation of a colony on the island of Borneo, to meet diplomats and consulate representatives, to carry out soundings and coast surveys to improve sea-charts, and to make meteorological observations. The "qualification list" indicates that all these tasks were fulfilled according to expectations. However, an incident on Borneo in 1875 took the life of two of his sailors. In its aftermath he did not react according to rules, he was reproached by the Navy Section of the Imperial War Ministry, and his career as a ship commander came to an end. Besides the Austrian expedition to observe the Venus transit of 1874 in Yokohama, a second one was carried out by the astronomers Eduard Weiss and Theodor Oppolzer in Jassy (Romania), which was supported by the Vienna Academy of Sciences.

  8. Craniopharyngioma: history.

    PubMed

    Barkhoudarian, Garni; Laws, Edward R

    2013-03-01

    One of the most challenging parasellar tumors, the craniopharyngioma was first described by Friedrich Albert von Zenker in 1857. Following improved understanding of pituitary gland physiology and development, Jakob Erdheim became the first to accurately describe the histopathological characteristics of a craniopharyngioma. Babinski's described the clinical presentation of these patients, with "sexual infantilism and dystrophic adiposity." The first successful surgical resection of a craniopharyngioma was performed by A. E. Halstead of Chicago of July 21st, 1909. Harvey Cushing embraced the transsphenoidal approach for the majority of his pituitary operations, but favored the transcranial approach for craniopharyngiomas. The introduction of antibiotics, corticosteroids, and microscopy significantly improved surgical outcomes. As technology improved, trans-cranial and transsphenoidal approaches were implemented depending on tumor characteristics. Adjuvant therapy, such as stereotactic radiosurgery, radioisotope brachytherapy, and intracapsular chemotherapy have improved overall tumor control rates and decreased the incidence of complications. Building on over 100 years of surgery for "the most formidable of intracranial tumors," results continue to improve. Regardless, challenges continue to remain requiring surgical insight and innovation. PMID:22744873

  9. Folding into being: early embryology and the epistemology of rhythm.

    PubMed

    Wellmann, Janina

    2015-03-01

    Historians have often described embryology and concepts of development in the period around 1800 in terms of "temporalization" or "dynamization". This paper, in contrast, argues that a central epistemological category in the period was "rhythm", which played a major role in the establishment of the emerging discipline of biology. I show that Caspar Friedrich Wolff's epigenetic theory of development was based on a rhythmical notion, namely the hypothesis that organic development occurs as a series of ordered rhythmical repetitions and variations. Presenting Christian Heinrich Pander's and Karl Ernst von Baer's theory of germ layers, I argue that Pander and Baer regarded folding as an organizing principle of ontogenesis, and that the principle's explanatory power stems from their understanding of folding as a rhythmical figuration. In a brief discussion of the notion of rhythm in contemporary music theory, I identify an underlying physiological epistemology in the new musical concept of rhythm around 1800. The paper closes with a more general discussion of the relationship between the rhythmic episteme, conceptions of life, and aesthetic theory at the end of the eighteenth century.

  10. Study of the rheological behaviour of human blood using a controlled stress rheometer.

    PubMed

    Alves, Maria M; Rocha, Cristina; Gonçalves, Maria P

    2013-01-01

    The aim of this work was to investigate the rheological behaviour of human blood, in a controlled stress rheometer, using different cone-plate and parallel plate geometries. Steady-shear (flow curves and kinetics) and oscillatory (strain, frequency and time sweeps) tests were performed at 37°C. The results demonstrated that rheological data are significantly influenced by the measuring geometry and the rheological parameters obtained from rheological models must be analysed with great caution. The Cross model provided a better fit of the flow curves and the Power Law model gave a better concordance between the rheological parameters obtained with the different measuring systems. The oscillatory measurements demonstrated a linear viscoelastic behaviour below a critical frequency and the Friedrich-Braun model described well the frequency sweeps experimental data in that region. The correlation between steady-shear and oscillatory properties (Cox-Merz rule) suggests that the two methods can be complementary and may give important information on red blood cells aggregation and deformability. Results from oscillatory time sweeps confirm a blood aggregation process in two steps.

  11. Die Deutsche Statistische Gesellschaft in der Weimarer Republik und während der Nazidiktatur

    NASA Astrophysics Data System (ADS)

    Wilke, Jürgen

    Nach anfänglichen Schwierigkeiten durch den 1. Weltkrieg erlangte die Deutsche Statistische Gesellschaft (DStatG) unter dem renommierten Statistiker und Vorsitzenden der DStatG, Friedrich Zahn, durch eine Vielzahl von Aktivitäten hohes Ansehen. Es gab Bestrebungen, Statistiker aus allen Arbeitsfeldern der Statistik in die DStatG zu integrieren, wobei die "Mathematische Statistik" nur zögerlich akzeptiert wurde (Konjunkturforschung, Zeitreihenanalyse). Nach der Machtübernahme 1933 durch Adolf Hitler geriet die DStatG in das Fahrwasser nationalsozialistischer Ideologie und Politik (Führerprinzip, Gleichschaltung des Vereinswesens). Damit war eine personelle Umstrukturierung in der DStatG verbunden. Politisch Missliebige und rassisch Verfolgte mussten die DStatG verlassen (Bernstein, Freudenberg, Gumbel u.a.). Unter den Statistikern gab es alle Abstufungen im Verhalten zum Regime von Ablehnung und zwangsweiser Anpassung über bereitwilliges Mitläufertum bis zu bewusster Täterschaft. Besonders die Bevölkerungsstatistik wurde durch die NS- Rassenpolitik auf lange Sicht diskreditiert. Im Rahmen von Wirtschaftsplanung und Aufrüstung wurden neue zukunftsträchtige statistische Modelle (Grünig, Bramstedt, Leisse) entwickelt.

  12. [Hermann Lebert (1813-1878): natural scientist, spa doctor, histopathologist and clinician in Switzerland, France and Germany].

    PubMed

    Kaiser, H

    2010-07-01

    H. Lebert was in many ways an extraordinary personality. He began is career as a scientist performing experimental research in botany and zoology. After a short period as a spa doctor--work he approached on a scientific basis--he performed one of the first microscopic tissue analyses, as well as writing two significant works with a wealth of pictures on pathophysiology and histopathology, thereby paving the way for cellular pathology. In addition to general problems relating to inflammation, he concentrated on tumors and tuberculosis. He was one of the first to recommend pre-operative histology, making him a pioneer of biopsy diagnostics.As a clinician he worked in nearly all areas of internal medicine, including neurology, and published a large number of monographs, of which the first German monograph on acute articular rheumatism was one. Rheumatology played a considerable role in both his histopathological and clinical activities.Of particular interest is the fact that Lebert frequently travelled between Switzerland, France and Germany and was applauded in all three as a great scientist, as awards from both Napoleon III and the Prussian King Friedrich Wilhelm IV can testify.

  13. Nietzche's echo--a dialogue with Thomas Altizer.

    PubMed

    Moss, David M

    2010-03-01

    Prophets provoke psychological unrest, especially when exposing accepted beliefs as profound deceptions. The biblical prophets exemplify such confrontation as do certain atheists ardently opposed to the images of God created by those seers. The German philosopher Friedrich Nietzsche dramatically illustrates this type of counterforce to the Judeo-Christian tradition. His prophet Zarathustra is intended to be a model for the modern mind, one free of superstitions inflicted by antiquated religious dogma. Nietzsche's credo "God is dead" served as a declaration for the nineteenth century. In the twentieth century, it became a theological diagnosis. As a "movement," or "tenor," the death of God or radical theology was spearheaded by Thomas Altizer, a well-published young professor center-staged during the turbulent 1960s. His work foreshadows a new strain of atheism currently represented by biologist Richard Dawkins (2006, The God delusion. New York: Houghton Mifflin), philosopher Daniel Dennett (2006, Breaking the spell. New York: Penquin), neuroscientist Sam Harris (2004, The end of faith. New York: W.W. Norton; 2008, Letter to a Christian nation. New York: Vintage), journalist Christopher Hitchens (2007, God is not great. New York: Twelve), and mathematician John Allen Paulos (Paulos 2008, Irreligion. New York: Hill & Wang). This twenty-first century crusade against belief in God is best understood as a psychodynamic ignited by Altizer's Christian atheism. The present dialogue reflects that dynamic while the prologue and epilogue reveal evidence of Providence amidst claims of God's demise in contemporary history. PMID:19399624

  14. The learning type makes the difference - the interrelation of Kolb's learning styles and psychological status of preclinical medical students at the University of Erlangen.

    PubMed

    Burger, Pascal H; Scholz, Michael

    2014-01-01

    Theories on learning styles and types have been integral to discussions on the basics of teaching for nearly 40 years. The learning style typology of Kolb divides learners into four groups (Diverger, Assimilator, Converger and Accomodator), which differ both in terms of their learning behaviour as well as personality and preferences. We studied the sense of coherence and burnout symptoms in medical students of the preclinical semesters (1(st) to 4(th) semester) at the Friedrich-Alexander University of Erlangen within the context of the observed learning styles. A total of 530 students were interviewed in winter semester 2012/13 using standardized psychometric questionnaires. Our students showed a significant correlation between the respective learning styles and expression of a sense of coherence, as well as cognitive and emotional burnout symptoms. The learning styles of the students differed significantly within these same parameters. We also demonstrated that learning styles and types not only influence study performance, but that there are also relationships to sense of coherence and psychological ailments. A more forward-looking integration of the theory of learning types in the medical education curriculum could positively influence both the performance and psychological well-being of the students.

  15. Pulmonary Alveolar Microlithiasis "Stone Lungs": A Case of Clinico-Radiological Dissociation.

    PubMed

    Chu, Andrew; Shaharyar, Sameer; Chokshi, Binna; Bhardwaj, Nikhil

    2016-01-01

    Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by deposition of spherical calcium phosphate microliths called calcospherites within the alveoli. PAM was first described by Friedrich in 1856 and then by Harbitz in 1918. The disease pathogenesis is based on mutations in the SLC34A2 gene that encodes for the Type IIb sodium-phosphate cotransporter. The majority of the patients are diagnosed at an early age, usually between the ages of 20 and 40 years. The hallmark of this disease is a striking dissociation between the radiological findings and the mild clinical symptoms.  We report a case of 35-year-old woman who presented post-motor vehicle accident with back pain and with minimal dyspnea on exertion. The final diagnosis was made after computed tomography and lung biopsy. The present case exhibits the remarkable clinico-radiological dissociation with complete calcification of the lungs on radiographic images with a relatively mild clinical presentation. PMID:27688986

  16. Quantum Chemistry in Great Britain: Developing a Mathematical Framework for Quantum Chemistry

    NASA Astrophysics Data System (ADS)

    Simões, Ana; Gavroglu, Kostas

    By 1935 quantum chemistry was already delineated as a distinct sub-discipline due to the contributions of Fritz London, Walter Heitler, Friedrich Hund, Erich Hückel, Robert Mulliken, Linus Pauling, John van Vleck and John Slater. These people are credited with showing that the application of quantum mechanics to the solution of chemical problems was, indeed, possible, especially so after the introduction of a number of new concepts and the adoption of certain approximation methods. And though a number of chemists had started talking of the formation of theoretical or, even, mathematical chemistry, a fully developed mathematical framework of quantum chemistry was still wanting. The work of three persons in particular-of John E. Lennard-Jones, Douglas R. Hartree, and Charles Alfred Coulson-has been absolutely crucial in the development of such a framework. In this paper we shall discuss the work of these three researchers who started their careers in the Cambridge tradition of mathematical physics and who at some point of their careers all became professors of applied mathematics. We shall argue that their work consisted of decisive contributions to the development of such a mathematical framework for quantum chemistry.

  17. The Cauchy-Lagrangian method for numerical analysis of Euler flow

    NASA Astrophysics Data System (ADS)

    Podvigina, O.; Zheligovsky, V.; Frisch, U.

    2016-02-01

    A novel semi-Lagrangian method is introduced to solve numerically the Euler equation for ideal incompressible flow in arbitrary space dimension. It exploits the time-analyticity of fluid particle trajectories and requires, in principle, only limited spatial smoothness of the initial data. Efficient generation of high-order time-Taylor coefficients is made possible by a recurrence relation that follows from the Cauchy invariants formulation of the Euler equation (Zheligovsky and Frisch, 2014 [44]). Truncated time-Taylor series of very high order allow the use of time steps vastly exceeding the Courant-Friedrichs-Lewy limit, without compromising the accuracy of the solution. Tests performed on the two-dimensional Euler equation indicate that the Cauchy-Lagrangian method is more - and occasionally much more - efficient and less prone to instability than Eulerian Runge-Kutta methods, and less prone to rapid growth of rounding errors than the high-order Eulerian time-Taylor algorithm. We also develop tools of analysis adapted to the Cauchy-Lagrangian method, such as the monitoring of the radius of convergence of the time-Taylor series. Certain other fluid equations can be handled similarly.

  18. A world from brave to new: Talcott Parsons and the war effort at Harvard University.

    PubMed

    Gerhardt, U

    1999-01-01

    This article argues that for Parsons and some of his colleagues at Harvard, the Second World War and the post-war period provided a context in which their work contributed to the transformation from totalitarianism to democracy in Central Europe (especially Germany) and Japan. The various agendas of Parsons' work are shown, supplemented by that of three of his colleagues with whom he collaborated (Gordon W. Allport, Carl J. Friedrich, Clyde Kluckhohn). The immediate effect of this work, for Parsons, however, meant frustration rather than fame, and his eventual reputation, I maintain, came unexpectedly with the third of his three attempts in the immediate post-war period to sum up what he believed were crucial insights that the Second World War had yielded concerning the ways in which sociology could contribute to the analytical understanding of democracy. The significance of this work is that it was both political and scientific. Because of the world situation of the 1940s, when the Holocaust in Germany was the nadir of civilization, Parsons believed that social science could contribute to the cause of making the world safe for future democracy. In the 1940s, this future depended on brave citizens, or such might have been Parsons' worldview. Targets envisaged for the 1950s, then, were community and citizenship in the newly democratic societies such as (West) Germany, the land that defeated Nazism.

  19. ["Haemorrhoidal colic", "strong pills of stahl", and "quacks". Johann Gottwerth Müller, writer of the enlightenment, critic of medicine and his evils in letters and books].

    PubMed

    Ritter, Alexander

    2007-01-01

    Johann Gottwerth Müller, a so called "independent author", was one of the most successful novelists in the German Enlightenment around 1800. Educated as a scholar and trained as a physician, although not a practicing physician, Müller was sick throughout his life and constantly reflects on his diseases, and on what he considered to be an insufficient "medical system" and a socially "sick" society. This outlook is revealed by his library (in 1828: about 13300 volumes, of which 254 volumes of medical publications), his correspondence and his novels. Letters he exchanged with the publisher Friedrich Nicolai (74 letters between 1777 and 1796) about private and business affairs show that Miller uses statements about his sickness in order to win sympathy, to document his sufferings as part of an "independent" writer's identity, as a metaphor for social health, and as a means for excuses and compulsions in business connections. The didactic novels serve the author's transformation of individual suffering into the perspective of an enlightened humanitarian development of the government, the society, and the medical system within the structured society of his day. PMID:18354992

  20. Politics, Morality, Innovation, and Misrepresentation in Physical Science and Technology

    NASA Astrophysics Data System (ADS)

    Buchwald, Jed Z.

    2016-08-01

    The pressures of politics, the desire to be first in innovation, moral convictions, and the potential dangers of error are all factors that have long been at work in the history of science and technology. Every so often, the need to reach a result may require leaving out a few steps here and there. Historians think and argue best through stories, so what follows are several tales, each of which exemplifies one or more of these aspects, though some reach back nearly two hundred years. The first concerns the depletion of the ozone layer; the second involves the discovery of electric waves by Heinrich Hertz in 1888; the third concerns the controlled production of electromagnetic radiation by Guglielmo Marconi and John Ambrose Fleming in the early 1900s; the fourth portrays the circumstances surrounding Joseph von Fraunhofer's discovery and use of the spectral lines in the 1810s; our final case involves a bitter controversy between the physicist Hermann von Helmholtz and the astronomer Friedrich Zöllner in the 1890s.

  1. Validation and Simulation of ARES I Scale Model Acoustic Test -1- Pathfinder Development

    NASA Technical Reports Server (NTRS)

    Putnam, G. C.

    2011-01-01

    The Ares I Scale Model Acoustics Test (ASMAT) is a series of live-fire tests of scaled rocket motors meant to simulate the conditions of the Ares I launch configuration. These tests have provided a well documented set of high fidelity measurements useful for validation including data taken over a range of test conditions and containing phenomena like Ignition Over-Pressure and water suppression of acoustics. To take advantage of this data, a digital representation of the ASMAT test setup has been constructed and test firings of the motor have been simulated using the Loci/CHEM computational fluid dynamics software. Within this first of a series of papers, results from ASMAT simulations with the rocket in a held down configuration and without water suppression have then been compared to acoustic data collected from similar live-fire tests to assess the accuracy of the simulations. Detailed evaluations of the mesh features, mesh length scales relative to acoustic signals, Courant-Friedrichs-Lewy numbers, and spatial residual sources have been performed to support this assessment. Results of acoustic comparisons have shown good correlation with the amplitude and temporal shape of pressure features and reasonable spectral accuracy up to approximately 1000 Hz. Major plume and acoustic features have been well captured including the plume shock structure, the igniter pulse transient, and the ignition overpressure. Finally, acoustic propagation patterns illustrated a previously unconsidered issue of tower placement inline with the high intensity overpressure propagation path.

  2. Böttger stoneware from North America and Europe; are they authentic

    NASA Astrophysics Data System (ADS)

    Swann, Charles P.; Nelson, Christina H.

    2000-03-01

    In the early 18th century, Johann Friedrich Böttger, an alchemist recently arrived in Dresden, was assigned to ceramic experimentation under the orders of Augustus the Strong, Elector of Saxony and King of Poland. The Elector and his advisors hoped to discover the secret of making hard paste porcelain like the wares imported into Europe from China and Japan. In 1706-1707, Böttger produced his first ceramic body, a red stoneware similar to the wares produced in Yixing, China. The first objects were made following the forms of chinese prototypes or European metalwork of the period. Recently, the authenticity of a number of `Böttger' objects in various museums and private collections in North America and Europe has been questioned. To aide in resolving these questions several non-destructive analytical techniques have been employed, the most important being PIXE. This report is on an initial study of 25 objects with 16 elements from Al to Zr and Pb being analysed. The results strongly suggest three different groupings, one of objects from the Meissen factory during the 20th century, one from the work of Böttger himself early in the 18th century and one from an as yet unknown time period and site. The first two groups were previously identified by one of the authors (C.N.).

  3. [Techniques of mediation. Chemistry as a combination of work, teaching and research: the case of J. F. A. Göttling].

    PubMed

    Frercks, Jan

    2008-01-01

    Atypical career of a chemist in Germany around 1800 consisted of being trained as an apothecary, followed by an occupation as a professor at a university or another institution of higher education. These conditions deeply influenced the concept and the practice of chemistry as a science. Johann Friedrich August Göttling is an intriguing example for merging education and daily duties of teaching with the self-image of a scientific chemist. He linked chemical teaching, work, and research by using different hybrid media, such as the Almanach oder Taschenbuch für Scheidekünstler und Apotheker, a stove specifically designed for the narrow student's room, portable laboratories, a pharmaceutical boarding school and textbooks. This allowed him to practice three different forms of chemistry as a science. A "socio-epistemological diagram" of German chemistry around 1800 shows that these forms neatly corresponded to the then predominant three-level epistemology. In particular, the concept of a chemical fact served to link pharmaceutical practice with teaching practice, while granting only the chemistry done by professors the status of a science. PMID:19244834

  4. FIRST REPORTS OF CLINICAL PHARMACOKINETICS IN NIGERIA

    PubMed Central

    Michael, O.S.

    2015-01-01

    The German Friedrich Hartmut Dost (1910-1985) introduced the word Pharmacokinetics. Clinical pharmacokinetics is the direct application of knowledge regarding a drug's pharmacokinetics to a therapeutic situation in an individual or a population. It is the basis of therapeutic drug monitoring with the ultimate goal of keeping drugs safe. This branch of pharmacology has become the most relevant to the sub-specialty of clinical pharmacology. First reports of Clinical Pharmacokinetics in Nigeria can be credited to two gifted Nigerians, Prof Ayodele O. Iyun and Prof Lateef A. Salako, both of whom were affiliated to the great institutions- University of Ibadan (UI) and the Teaching Hospital, University College Hospital (UCH). Prof A.O Iyun was Nigeria's first home-trained Clinical Pharmacologist, while Prof L.A. Salako played a most significant role in the creation of the Department of Clinical Pharmacology, UCH. This edition of the Chronicles highlights a few of the first reports of this exciting branch of pharmacology in Nigeria. This historical review is based on publications listed on the United States National Library of Medicine database (PUBMED). PMID:26807087

  5. a Millennium of Geomagnetism

    NASA Astrophysics Data System (ADS)

    Stern, David P.

    2002-11-01

    The history of geomagnetism began around the year 1000 with the discovery in China of the magnetic compass. Methodical studies of the Earth's field started in 1600 with William Gilbert's De Magnete [Gilbert, 1600] and continued with the work of (among others) Edmond Halley, Charles Augustin de Coulomb, Carl Friedrich Gauss, and Edward Sabine. The discovery of electromagnetism by Hans Christian Oersted and André-Marie Ampére led Michael Faraday to the notion of fluid dynamos, and the observation of sunspot magnetism by George Ellery Hale led Sir Joseph Larmor in 1919 to the idea that such dynamos could sustain themselves naturally in convecting conducting fluids. From that came modern dynamo theory, of both the solar and terrestrial magnetic fields. Paleomagnetic studies revealed that the Earth's dipole had undergone reversals in the distant past, and these became the critical evidence in establishing plate tectonics. Finally, the recent availability of scientific spacecraft has demonstrated the intricacy of the Earth's distant magnetic field, as well as the existence of magnetic fields associated with other planets and with satellites in our solar system.

  6. Effect of Model Sorptive Phases on Phenanthrene Biodegradation: Molecular Analysis of Enrichments and Isolates Suggests Selection Based on Bioavailability

    PubMed Central

    Friedrich, M.; Grosser, R. J.; Kern, E. A.; Inskeep, W. P.; Ward, D. M.

    2000-01-01

    Reduced bioavailability of nonpolar contaminants due to sorption to natural organic matter is an important factor controlling biodegradation of pollutants in the environment. We established enrichment cultures in which solid organic phases were used to reduce phenanthrene bioavailability to different degrees (R. J. Grosser, M. Friedrich, D. M. Ward, and W. P. Inskeep, Appl. Environ. Microbiol. 66:2695–2702, 2000). Bacteria enriched and isolated from contaminated soils under these conditions were analyzed by denaturing gradient gel electrophoresis (DGGE) and sequencing of PCR-amplified 16S ribosomal DNA segments. Compared to DGGE patterns obtained with enrichment cultures containing sand or no sorptive solid phase, different DGGE patterns were obtained with enrichment cultures containing phenanthrene sorbed to beads of Amberlite IRC-50 (AMB), a weak cation-exchange resin, and especially Biobead SM7 (SM7), a polyacrylic resin that sorbed phenanthrene more strongly. SM7 enrichments selected for mycobacterial phenanthrene mineralizers, whereas AMB enrichments selected for a Burkholderia sp. that degrades phenanthrene. Identical mycobacterial and Burkholderia 16S rRNA sequence segments were found in SM7 and AMB enrichment cultures inoculated with contaminated soil from two geographically distant sites. Other closely related Burkholderia sp. populations, some of which utilized phenanthrene, were detected in sand and control enrichment cultures. Our results are consistent with the hypothesis that different phenanthrene-utilizing bacteria inhabiting the same soils may be adapted to different phenanthrene bioavailabilities. PMID:10877758

  7. Darwin and the linguists: the coevolution of mind and language, part 2. The language-thought relationship.

    PubMed

    Alter, Stephen G

    2008-03-01

    This paper examines Charles Darwin's idea that language-use and humanity's unique cognitive abilities reinforced each other's evolutionary emergence-an idea Darwin sketched in his early notebooks, set forth in his Descent of man (1871), and qualified in Descent's second (1874) edition. Darwin understood this coevolution process in essentially Lockean terms, based on John Locke's hints about the way language shapes thinking itself. Ironically, the linguist Friedrich Max Müller attacked Darwin's human descent theory by invoking a similar thesis, the German romantic notion of an identity between language and thought. Although Darwin avoided outright contradiction, when he came to defend himself against Müller's attacks, he undercut some of his own argumentation in favor of the coevolution idea. That is, he found it difficult to counter Müller's argument while also making a case for coevolution. Darwin's efforts in this area were further complicated by British and American writers who held a naturalistic view of speech origins yet still taught that language had been invented by fully evolved homo sapiens, thus denying coevolution.

  8. Worldwide Geomagnetic Data Collection and Management

    NASA Astrophysics Data System (ADS)

    Mandea, Mioara; Papitashvili, Vladimir

    2009-11-01

    Geomagnetic data provided by different platforms piece together a global picture of Earth's magnetic field and its interaction with geospace. Furthermore, a great diversity of the geomagnetic field changes, from secular (over decades to centuries) to short time variations (down to minutes and seconds), can be detected only through continued observations. An international effort to watch and record geomagnetic changes first began in the 1830s with a network of scientific observers organized by Karl Friedrich Gauss in Germany, and this effort has continued since then. One of the most remarkable achievements in understanding the geomagnetic field morphology and time behavior was made possible by the International Geophysical Year (IGY), an exploration and research effort that lasted for 18 months, starting on 1 July 1957. The IGY encompassed 11 geoscience disciplines, including geomagnetism. The IGY has represented a giant step forward in the quality and quantity of worldwide geomagnetic measurements, as well as in the widespread interest in magnetic measurements. A half century of probing the geomagnetic field spatial and temporal variations has produced a number of outstanding results, and the interested reader can find recent reviews on various geomagnetic field topics (from measurements to modeling) in Encyclopedia of Geomagnetism and Paleomagnetism [Gubbins and Herrero-Bervera, 2007] or Treatise on Geophysics: Geomagnetism [Kono, 2007].

  9. [Weizsäcker, Bethe and the Nobel Prize].

    PubMed

    Schaaf, Michael

    2014-01-01

    For his work on nuclear physics Carl Friedrich von Weizsäcker was twice nominated for the Nobel Prize in physics. Bethe had worked on the energy production in stars at about the same time as Weizsäcker but independently from him. The Nobel Committee valued the structural depth of BETHE'S work more than Weizsäcker's temporal priority because Bethe had described the nuclear reactions quantitatively and had shown a much deeper understanding of the nuclear processes in the centre of stars whereas Weizsäcker had worked more qualitatively. There are no reasons to believe that political resentments towards Weizsäcker played any significant role in awarding of the Nobel Prize in Physics in 1967 only to Bethe. The lives and works of Weizsäcker and Bethe show some remarkable parallels, ranging from calculating the binding energy in nuclei to the energy production in sun-like and massive stars to peace- and disarmament initiatives.

  10. Analysis and Improvement of Upwind and Centered Schemes on Quadrilateral and Triangular Meshes

    NASA Technical Reports Server (NTRS)

    Huynh, H. T.

    2003-01-01

    Second-order accurate upwind and centered schemes are presented in a framework that facilitates their analysis and comparison. The upwind scheme employed consists of a reconstruction step (MUSCL approach) followed by an upwind step (Roe's flux-difference splitting). The two centered schemes are of Lax-Friedrichs (L-F) type. They are the nonstaggered versions of the Nessyahu-Tadmor (N-T) scheme and the CE/SE method with epilson = 1/2. The upwind scheme is extended to the case of two spatial dimensions (2D) in a straightforward manner. The N-T and CE/SE schemes are extended in a manner similar to the 2D extensions of the CE/SE scheme by Wang and Chang for a triangular mesh and by Zhang, Yu, and Chang for a quadrilateral mesh. The slope estimates, however, are simplified. Fourier stability and accuracy analyses are carried out for these schemes for the standard 1D and the 2D quadrilateral mesh cases. In the nonstandard case of a triangular mesh, the triangles must be paired up when analyzing the upwind and N-T schemes. An observation resulting in an extended N-T scheme which is faster and uses only one-third of the storage for flow data compared with the CE/SE method is presented. Numerical results are shown. Other improvements to the schemes are discussed.

  11. Stability constraints for oceanic numerical models: implications for the formulation of time and space discretizations

    NASA Astrophysics Data System (ADS)

    Lemarié, F.; Debreu, L.; Madec, G.; Demange, J.; Molines, J. M.; Honnorat, M.

    2015-08-01

    Except for vertical diffusion (and possibly the external mode and bottom drag), oceanic models usually rely on explicit time-stepping algorithms subject to Courant-Friedrichs-Lewy (CFL) stability criteria. Implicit methods could be unconditionally stable, but an algebraic system must be solved at each time step and other considerations such as accuracy and efficiency are less straightforward to achieve. Depending on the target application, the process limiting the maximum allowed time-step is generally different. In this paper, we introduce offline diagnostics to predict stability limits associated with internal gravity waves, advection, diffusion, and rotation. This suite of diagnostics is applied to a set of global, regional and coastal numerical simulations with several horizontal/vertical resolutions and different numerical models. We show that, for resolutions finer that 1/2°, models with an Eulerian vertical coordinate are generally constrained by vertical advection in a few hot spots and that numerics must be extremely robust to changes in Courant number. Based on those results, we review the stability and accuracy of existing numerical kernels in vogue in primitive equations oceanic models with a focus on advective processes and the dynamics of internal waves. We emphasize the additional value of studying the numerical kernel of oceanic models in the light of coupled space-time approaches instead of studying the time schemes independently from spatial discretizations. From this study, we suggest some guidelines for the development of temporal schemes in future generation multi-purpose oceanic models.

  12. [The Essen-based steel producer Alfred Krupp (1812-1887) as a reader of the flora and fauna of the Gulf of Naples. A look at the relationship of Anton Dohrn (1840-1909) to the house Krupp].

    PubMed

    Müller, Irmgard

    2015-01-01

    A unfavourable notice written by industrial magnate Alfred Krupp (1812-1887) has been discovered on the posterior cover sheet of the first volume of the monumental series Fauna und Flora des Golfes von Neapel, edited by the Zoological Station at Naples (1880) Krupp's handwritten statement affords the opportunity to discuss in more detail the intricate relationship between the founder of the first marine biology station, Anton Dohrn (1840-1909), and the owner of the greatest steel factory in Europe, the Krupp-family at Essen. Although Anton Dohrn did not know about Krupp's disapproving comment he had a fine unerring instinct for the mentality of his negotiating partner, whose way of thinking rather aimed at the practical success and completion of armament factory, preventing thus a the serious rapprochement between the two personalities. Even when the Krupp-heir, Friedrich Alfred Krupp, later devoted to questions about marine biology in his new built house at Capri, and was willing to support the Zoological Station with high sponsoring, Anton Dohrn maintained a reserved attitude towards the Krupp's offer to support the marine research financially. Likewise, he remained unimpressed, when the steel magnate was shook by the smear campaign in Capri that ultimately led to Krupp's death in November 1902.

  13. [Evaluation of a face model for surgical education].

    PubMed

    Schneider, G; Voigt, S; Rettinger, G

    2011-09-01

    The complex anatomy of the human face requires a high degree of experience and skills in surgical dressing of facial soft tissue defects. The previous education contains literature studies and supervision during surgery, according to surgical spectrum of the educating hospital. A structured education including a training of different surgical methods on a model and slow increase of complexity could improve considerably the following education related to the patient.During a cooperative project, the 3 di GmbH and the Department of Otolaryngology at the Friedrich-Schiller-University Jena developed a face model for surgical education that allows the training of surgical interventions in the face. The model was used during the 6th and 8th Jena Workshop for Functional and Aesthetic Surgery as well as a workshop for surgical suturation, and tested and evaluated by the attendees.The attendees mostly rated the work-ability of the models and the possibility to practice on a realistic face model with artificial skin very well and beneficial. This model allows a repeatable and structured education of surgical standards, and is very helpful in preparation for operating facial defects of a patient. PMID:21913151

  14. ["A decision meaning a new foundation...": from the Kaiser Wilhelm Institute for Anthropology, Human Genetics and Eugenics to the Max Planck Institute for Molecular Genetics].

    PubMed

    Sachse, Carola

    2011-01-01

    The Max Planck Institute for Molecular Genetics (MPIMG) in Berlin-Dahlem dates its establishment to 1964. Its homepage makes no mention of its predecessor institutes, the Kaiser Wilhelm Institute for Anthropology, Human Genetics and Eugenics (KWIA) and the subsequent MPI for Comparative Genetics and Hereditary Pathology (MPIVEE). This article traces the two critical phases of transition regarding the constellations of academic staff, institutional and epistemic ruptures and continuities specific to the era. Only one of the five department heads from the final war years, Hans Nachtsheim, remained a researcher within the Max Planck Society (MPG); he nevertheless continued to advocate the pre-war and wartime eugenic agenda in the life sciences and social policy. The generational change of 1959/60 became a massive struggle within the institute, in which microbial genetics (with Fritz Kaudewitz) was pitted against human genetics (with Friedrich Vogel) and managed to establish itself after a fresh change in personnel in 1964/65. For the Dahlem institute, this involved a far-reaching reorientation of its research, but for the genetically oriented life sciences in the Max Planck Society as a whole it only meant that molecular biology, which was already being pursued in the West German institutes, gained an additional facility. With this realignment of research traditions, the Society was able to draw a line under the Nazi past without having to address it head-on.

  15. A world from brave to new: Talcott Parsons and the war effort at Harvard University.

    PubMed

    Gerhardt, U

    1999-01-01

    This article argues that for Parsons and some of his colleagues at Harvard, the Second World War and the post-war period provided a context in which their work contributed to the transformation from totalitarianism to democracy in Central Europe (especially Germany) and Japan. The various agendas of Parsons' work are shown, supplemented by that of three of his colleagues with whom he collaborated (Gordon W. Allport, Carl J. Friedrich, Clyde Kluckhohn). The immediate effect of this work, for Parsons, however, meant frustration rather than fame, and his eventual reputation, I maintain, came unexpectedly with the third of his three attempts in the immediate post-war period to sum up what he believed were crucial insights that the Second World War had yielded concerning the ways in which sociology could contribute to the analytical understanding of democracy. The significance of this work is that it was both political and scientific. Because of the world situation of the 1940s, when the Holocaust in Germany was the nadir of civilization, Parsons believed that social science could contribute to the cause of making the world safe for future democracy. In the 1940s, this future depended on brave citizens, or such might have been Parsons' worldview. Targets envisaged for the 1950s, then, were community and citizenship in the newly democratic societies such as (West) Germany, the land that defeated Nazism. PMID:10398174

  16. The Kelvin–Helmholtz instability at Venus: What is the unstable boundary?

    PubMed Central

    Möstl, Ute V.; Erkaev, Nikolay V.; Zellinger, Michael; Lammer, Helmut; Gröller, Hannes; Biernat, Helfried K.; Korovinskiy, Daniil

    2011-01-01

    The Kelvin–Helmholtz instability gained scientific attention after observations at Venus by the spacecraft Pioneer Venus Orbiter gave rise to speculations that the instability contributes to the loss of planetary ions through the formation of plasma clouds. Since then, a handful of studies were devoted to the Kelvin–Helmholtz instability at the ionopause and its implications for Venus. The aim of this study is to investigate the stability of the two instability-relevant boundary layers around Venus: the induced magnetopause and the ionopause. We solve the 2D magnetohydrodynamic equations with the total variation diminishing Lax–Friedrichs algorithm and perform simulation runs with different initial conditions representing the situation at the boundary layers around Venus. Our results show that the Kelvin–Helmholtz instability does not seem to be able to reach its nonlinear vortex phase at the ionopause due to the very effective stabilizing effect of a large density jump across this boundary layer. This seems also to be true for the induced magnetopause for low solar activity. During high solar activity, however, there could occur conditions at the induced magnetopause which are in favour of the nonlinear evolution of the instability. For this situation, we estimated roughly a growth rate for planetary oxygen ions of about 7.6 × 1025 s−1, which should be regarded as an upper limit for loss due to the Kelvin–Helmholtz instability. PMID:22347723

  17. ["Fabulous things". Drug narratives about coca and cocaine in the 19th century].

    PubMed

    Wahrig, Bettina

    2009-12-01

    This contribution focuses on the history of Coca leaves and Cocaine in the second half of 19th century Europe. Even though, to date, no direct link has been established between the activities of the Milano physician Paolo Mantegazza, and the Göttingen chemist Friedrich Wöhler, it is not a mere coincidence that both published their findings in the same year, namely, 1859. Mantegazza authored the first treatise claiming that Coca had psychoactive qualities and touted its broad therapeutic faculties; he claimed that it should be introduced into European pharmacotherapy. In Wöhler's laboratory, cocaine was isolated from leaves by his pupil Alfred Niemann; later, Wilhelm Lossen refined and corrected Niemann's results. Narratives about medicinal drugs often streamline history into a story that starts with multiple meanings and impure matters and ends with well-defined substances, directed at clear-cut diseases and symptoms. In the case of Coca, however, the pure substance triggered no such process well into the 1880s, whereas the leaves continued to circulate as an exotic, pluripotent drug whose effects where miraculous and yet difficult to establish.

  18. Pharmacodynamic principles of homeopathy.

    PubMed

    Widakowich, J

    2000-05-01

    Homeopathy was already known to Hippocrates and further studied by Hahnemann. However, since the discovery of the medical effects of digitalis by William Withering around 1785, and the first synthesis of an organic molecule, urea, by Friedrich Wöhler in 1828, and through the further rapid evolution of modern pharmacological chemistry and molecular biology, it has gradually been abandoned as a serious therapeutic alternative to allopathy by most practitioners of scientifically founded medicine. Because a credible scientific explanation for its mode of action has been lacking, homeopathy is regarded by many medical researchers and scientists as, at best, placebo therapy, in spite of the fact that for centuries hosts of patients have testified to its effects. It is suggested that the gulf between homeopathy and allopathy can be reconciled if one takes into consideration modern knowledge of physiology, biochemistry and the physical properties of the water used in the potentiation process. A description of the mechanisms occurring during potentiation, both inside and outside a live mammalian organism, is presented.

  19. [Medicine and chemistry around the middle of the 19th century in Erlangen. Eugen Franz Freiherr von Gorup-Besanez (1817--1878) (author's transl)].

    PubMed

    Simmer, H H

    1981-07-01

    Eugen Franz Freiherr von Gorup-Besanez, born 1817 in Graz, was appointed on 28. 11. 1846 to the post of lecturer in the faculty of medicine of the University of Erlangen. He had previously studied medicine in Vienna, Padua and Munich, followed by physiological and clinical-chemical studies under Louis Andreas Buchner in Munich, and further studies in organic and analytical chemistry under Friedrich Wöhler in Göttingen. In 1849 in Erlangen he became reader in organic and analytical chemistry, then, in 1855, moved to the faculty of philosophy as professor of chemistry. Von Gorup-Besanez was one of the early representatives of clinical chemistry in Germany. He tried to help clinicians by the analysis of urine, blood and tissues. In his lectures and through his books he was an outstanding teacher. His greatest contribution was the discovery of the amino acid valine. The lack of a laboratory in the medical faculty and his dissatisfaction with what could be achieved in clinical chemistry at that time may chiefly explain his move from the medical to the philosophical faculty. The life of von Gorup-Besanez illustrates the difficulties faced by clinical chemistry and its exponents in the middle of the 19th century.

  20. Hands of beauty, hands of horror: fear and Egyptian art at the Fin de Siècle.

    PubMed

    Briefel, Aviva

    2008-01-01

    This essay examines the gothicization of Egyptian manual productions in late-Victorian mummy narratives. These narratives often isolate the mummy's hand as a signifier of craftsmanship, a troubling object for a culture that was mourning the figurative loss of its artisans' hands to mechanized production. Focusing on Bram Stoker's 1903 novel, The Jewel of Seven Stars, I contend that the horror of the mummy's hand emanates from its ambiguous position as an artifact that is itself a means of production. It displaces Friedrich Engels's conception of the Western hand as a self-creating appendage into the atavistic domain of a long-lost Egyptian tradition, and in doing so, it forces the English observer to recognize the irrecoverable nature of aesthetic craftsmanship. Brought into violent contact with the creative potential of the mummy's hand, the characters in Stoker's novel try to disassociate the mummy from manual production but only succeed in confirming their own status as products of a mechanized age. PMID:19069003

  1. G. F. Parrot and the theory of unconscious inferences.

    PubMed

    Allik, Jüri; Konstabel, Kenn

    2005-01-01

    In 1839, Georg Friedrich Parrot (1767-1852) published a short note about a peculiar visual phenomenon--the diminishing of the size of external objects situated at a relatively small distance from the window of a fast-moving train. For the explanation of this illusion, Parrot proposed a concept of unconscious inferences, a very rapid syllogistic conclusion from two premises, which anticipated the revival of Alhazen's theory of unconscious inferences by Hermann von Helmholtz, Wilhelm Wundt, and John Stuart Mill. He also advanced the notion that the speed of mental processes is not infinitely high and that it can be measured by means of systematic experimentation. Although Parrot was only partly correct in the description of the movement-induced changes of the perceived size, his general intention to understand basic mechanisms of the human mind was in harmony with the founding ideas of experimental psychology: it is possible to study the phenomena of the mind in the same general way that the physical world is studied, either in terms of mechanical or mathematical laws.

  2. Dissipative Properties of Quantum Systems

    PubMed Central

    Grecos, A. P.; Prigogine, I.

    1972-01-01

    We consider the dissipative properties of large quantum systems from the point of view of kinetic theory. The existence of a nontrivial collision operator imposes restrictions on the possible collisional invariants of the system. We consider a model in which a discrete level is coupled to a set of quantum states and which, in the limit of a large “volume,” becomes the Friedrichs model. Because of its simplicity this model allows a direct calculation of the collision operator as well as of related operators and the constants of the motion. For a degenerate spectrum the calculations become more involved but the conclusions remain simple. The special role played by the invariants that are functions of the Hamiltonion is shown to be a direct consequence of the existence of a nonvanishing collision operator. For a class of observables we obtain ergodic behavior, and this reformulation of the ergodic problem may be used in statistical mechanics to study the ergodicity of large quantum systems containing a small physical parameter such as the coupling constant or the concentration. PMID:16591994

  3. Validation of a two-step quality control approach for a large-scale human urine metabolomic study conducted in seven experimental batches with LC/QTOF-MS.

    PubMed

    Demetrowitsch, Tobias J; Petersen, Beate; Keppler, Julia K; Koch, Andreas; Schreiber, Stefan; Laudes, Matthias; Schwarz, Karin

    2015-01-01

    After his study of food science at the Rheinische Friedrich-Wilhelms University of Bonn, Tobias J Demetrowitsch obtained his doctoral degree in the research field of metabolomics at the Christian-Albrechts-University of Kiel. The present paper is part of his doctoral thesis and describes an extended strategy to evaluate and verify complex or large-scale experiments and data sets. Large-scale studies result in high sample numbers, requiring the analysis of samples in different batches. So far, the verification of such LC-MS-based metabolomics studies is difficult. Common approaches have not provided a reliable validation procedure to date. This article shows a novel verification process for a large-scale human urine study (analyzed by a LC/QToF-MS system) using a two-step validation procedure. The first step comprises a targeted approach that aims to examine and exclude statistical outliers. The second step consists of a principle component analysis, with the aim of a tight cluster of all quality controls and a second for all volunteer samples. The applied study design provides a reliable two-step validation procedure for large-scale studies and additionally contains an inhouse verification procedure. PMID:25558939

  4. On Kiefer’s American Eucyclops (Copepoda, Eucyclopinae): redescriptions and comments on the historical records of E. delachauxi, E. prionophorus, E. bondi and E. leptacanthus

    PubMed Central

    Mercado-Salas, Nancy F.; Suárez-Morales, Eduardo

    2014-01-01

    Abstract The freshwater copepod genus Eucyclops contains many supposedly cosmopolitan species whose taxonomic status is still under discussion; some of them represent species complexes. The problem is not exclusive to these widespread species; there are several American Eucyclops needing a taxonomic re-evaluation. Based on the examination of Friedrich Kiefer’s collection in Karlsruhe, Germany, the type specimens of four American species of Eucyclops (E. delachauxi (Kiefer, 1926), E. prionophorus Kiefer, 1931, E. bondi Kiefer, 1934, E. leptacanthus Kiefer, 1956) were re-examined and redescribed using upgraded descriptive standards. Kiefer’s translated descriptions and unpublished original drawings of these species are also presented. Characters like the ornamentation of the antennal basis, ornamentation of intercoxal sclerites of the swimming legs 1–4, length of basipodal seta of leg 1, ornamentation of caudal rami, the presence of aesthetascs and modified setae on the antennules in male, and the structure of the male sixth leg are compared herein to aid a more accurate separation of these American species. A revision of the American records of these species confirms that some are likely to refer to undescribed species. Overall, the diversity of the American Eucyclops appears to be underestimated and certainly deserves further study. PMID:24843261

  5. High Performance Parallel Methods for Space Weather Simulations

    NASA Technical Reports Server (NTRS)

    Hunter, Paul (Technical Monitor); Gombosi, Tamas I.

    2003-01-01

    This is the final report of our NASA AISRP grant entitled 'High Performance Parallel Methods for Space Weather Simulations'. The main thrust of the proposal was to achieve significant progress towards new high-performance methods which would greatly accelerate global MHD simulations and eventually make it possible to develop first-principles based space weather simulations which run much faster than real time. We are pleased to report that with the help of this award we made major progress in this direction and developed the first parallel implicit global MHD code with adaptive mesh refinement. The main limitation of all earlier global space physics MHD codes was the explicit time stepping algorithm. Explicit time steps are limited by the Courant-Friedrichs-Lewy (CFL) condition, which essentially ensures that no information travels more than a cell size during a time step. This condition represents a non-linear penalty for highly resolved calculations, since finer grid resolution (and consequently smaller computational cells) not only results in more computational cells, but also in smaller time steps.

  6. [Relationship between Copenhagen and Göttingen regarding earth magnetism].

    PubMed

    Reich, Karin

    2013-01-01

    Hans Christian Oersted is mostly known as the discoverer of electromagnetism and for being one of the physicists who were deeply influenced and fascinated by the romantic natural philosophy. In this article another side of Oersted is presented. What is underestimated until now is Oersted's contribution to the research of geomagnetism. Oersted stood in close contact with Carl Friedrich Gauss and Wilhelm Weber, whom he visited in 1834 in Göttingen. Oersted's aim was to learn the new developments in geomagnetism. Afterwards he was crucial in the building of a new magnetic observatory in Copenhagen as well as a second one with better equipment. Oersted formed a huge team for magnetic observations and the gathered data were sent to Gauss and Weber who published them. The correspondence between Oersted, Gauss and Weber was mostly dedicated to the transmission of these data, details about instruments and the best way of building a magnetic observatory. Unfortunately, Gauss and Weber had to stop their very successful collaboration in 1843, because Weber belonged to the Göttingen Seven and later on Oersted stopped his observations, because he had lost his partners in this research project.

  7. Nietzche's echo--a dialogue with Thomas Altizer.

    PubMed

    Moss, David M

    2010-03-01

    Prophets provoke psychological unrest, especially when exposing accepted beliefs as profound deceptions. The biblical prophets exemplify such confrontation as do certain atheists ardently opposed to the images of God created by those seers. The German philosopher Friedrich Nietzsche dramatically illustrates this type of counterforce to the Judeo-Christian tradition. His prophet Zarathustra is intended to be a model for the modern mind, one free of superstitions inflicted by antiquated religious dogma. Nietzsche's credo "God is dead" served as a declaration for the nineteenth century. In the twentieth century, it became a theological diagnosis. As a "movement," or "tenor," the death of God or radical theology was spearheaded by Thomas Altizer, a well-published young professor center-staged during the turbulent 1960s. His work foreshadows a new strain of atheism currently represented by biologist Richard Dawkins (2006, The God delusion. New York: Houghton Mifflin), philosopher Daniel Dennett (2006, Breaking the spell. New York: Penquin), neuroscientist Sam Harris (2004, The end of faith. New York: W.W. Norton; 2008, Letter to a Christian nation. New York: Vintage), journalist Christopher Hitchens (2007, God is not great. New York: Twelve), and mathematician John Allen Paulos (Paulos 2008, Irreligion. New York: Hill & Wang). This twenty-first century crusade against belief in God is best understood as a psychodynamic ignited by Altizer's Christian atheism. The present dialogue reflects that dynamic while the prologue and epilogue reveal evidence of Providence amidst claims of God's demise in contemporary history.

  8. Study of the rheological behaviour of human blood using a controlled stress rheometer.

    PubMed

    Alves, Maria M; Rocha, Cristina; Gonçalves, Maria P

    2013-01-01

    The aim of this work was to investigate the rheological behaviour of human blood, in a controlled stress rheometer, using different cone-plate and parallel plate geometries. Steady-shear (flow curves and kinetics) and oscillatory (strain, frequency and time sweeps) tests were performed at 37°C. The results demonstrated that rheological data are significantly influenced by the measuring geometry and the rheological parameters obtained from rheological models must be analysed with great caution. The Cross model provided a better fit of the flow curves and the Power Law model gave a better concordance between the rheological parameters obtained with the different measuring systems. The oscillatory measurements demonstrated a linear viscoelastic behaviour below a critical frequency and the Friedrich-Braun model described well the frequency sweeps experimental data in that region. The correlation between steady-shear and oscillatory properties (Cox-Merz rule) suggests that the two methods can be complementary and may give important information on red blood cells aggregation and deformability. Results from oscillatory time sweeps confirm a blood aggregation process in two steps. PMID:23579279

  9. SENSITIVITY OF HELIOSEISMIC TRAVEL TIMES TO THE IMPOSITION OF A LORENTZ FORCE LIMITER IN COMPUTATIONAL HELIOSEISMOLOGY

    SciTech Connect

    Moradi, Hamed; Cally, Paul S.

    2014-02-20

    The rapid exponential increase in the Alfvén wave speed with height above the solar surface presents a serious challenge to physical modeling of the effects of magnetic fields on solar oscillations, as it introduces a significant Courant-Friedrichs-Lewy time-step constraint for explicit numerical codes. A common approach adopted in computational helioseismology, where long simulations in excess of 10 hr (hundreds of wave periods) are often required, is to cap the Alfvén wave speed by artificially modifying the momentum equation when the ratio between the Lorentz and hydrodynamic forces becomes too large. However, recent studies have demonstrated that the Alfvén wave speed plays a critical role in the MHD mode conversion process, particularly in determining the reflection height of the upwardly propagating helioseismic fast wave. Using numerical simulations of helioseismic wave propagation in constant inclined (relative to the vertical) magnetic fields we demonstrate that the imposition of such artificial limiters significantly affects time-distance travel times unless the Alfvén wave-speed cap is chosen comfortably in excess of the horizontal phase speeds under investigation.

  10. [Humboldt as mediator: Schleiden and Mohl contra Liebig].

    PubMed

    Werner, P

    2001-01-01

    Justus Liebig's book Die organische Chemic in ihrer Anwendung auf Agricultur und Physiologie aroused strong opposition from scientists who felt that they were being attacked. A polarization arose particularly between Hugo von Mohl (1805-1872) and Matthias Jacob Schleiden (1805-1881) on one side, and Justus von Liebig (1803-1873) and his followers on the other side. The debate did not have the character of a purely scientific controversy, however, because social aspects also played a role. Alexander von Humboldt (1769-1859), who held the esteem of both parties, was able to intervene successfully to mediate this conflict. His task appeared at first difficult, but it turned out that both groups had a common enemy, the representatives and followers of the 'Romantic philosophy of nature'. Humboldt, who self-deprecatingly called himself a 'fossil', was forced to recognize that many of his friends and acquaintances, who stood nearer to, or even belonged among the founders of Naturphilosophie, for example, Friedrich Wilhelm Joseph von Schelling (1775-1854) and Johann Bernhard Wilbrand (1779-1846), were also under attack. Although he had earlier been inspired by the concerns and ideas of Schelling's Naturphilosophie, he now distanced himself from them in order to mediate between modern, experimental scientists. PMID:12557694

  11. General physiology, experimental psychology, and evolutionism. Unicellular organisms as objects of psychophysiological research, 1877-1918.

    PubMed

    Schloegel, Judy Johns; Schmidgen, Henning

    2002-12-01

    This essay aims to shed new light on the relations between physiology and psychology in the late nineteenth and early twentieth centuries by focusing on the use of unicellular organisms as research objects during that period. Within the frameworks of evolutionism and monism advocated by Ernst Haeckel, protozoa were perceived as objects situated at the borders between organism and cell and individual and society. Scholars such as Max Verworn, Alfred Binet, and Herbert Spencer Jennings were provoked by these organisms to undertake experimental investigations situated between general physiology and psychology that differed from the physiological psychology advocated by Wilhelm Wundt. Some of these investigations sought to locate psychological properties in the molecular structure of protoplasm; others stressed the existence of organic and psychological individuality in protozoa. In the following decades, leading philosophers such as Friedrich Nietzsche, Charles Sanders Peirce, and Henri Bergson, as well as psychological researchers like Sigmund Freud, integrated the results of these investigations into their reflections on such problems as the nature of the will, the structure of the ego, and the holistic nature of the reactions of organisms to their environment. PMID:12664793

  12. Differential distribution of calpain small subunit 1 and 2 in rat brain.

    PubMed

    Friedrich, Peter; Papp, Henrietta; Halasy, Katalin; Farkas, Attila; Farkas, Bence; Tompa, Peter; Kása, Peter

    2004-04-01

    Calpains, the Ca(2+)-dependent thiol proteases, are abundant in the nervous tissue. The ubiquitous enzyme forms in mammals are heterodimers consisting of a specific, micro or m, large (catalytic) subunit and, apparently, a common small (regulatory) subunit (CSS1). Recently, however, we described a second form of small subunit (CSS2), which is of restricted occurrence [Schád, E., Farkas, A., Jékely, G., Tompa, P. & Friedrich, P. (2002) Biochem. J., 362, 383-388]. Here we analysed the distribution of immunoreactivity in various parts of rat brain against two anti-CSS1 and two anti-CSS2 antibodies by correlated light and electron microscopy. Remarkably, the antibodies showed differential distribution in various parts of rat cortex: anti-CSS1 reacted mainly with perikarya and dendrites, whereas anti-CSS2 was more prominent in axons. In serial sections CSS2 and synaptophysin gave very similar patterns, i.e. these epitopes seem to colocalize. Electron microscopy confirmed that CSS1 was mainly localized postsynaptically in dendrites and somata, whereas CSS2 was found presynaptically. The hypothesis is advanced that these distinct distributions of calpain subunits may be related to the transport of these enzymes in nerve cells. PMID:15078555

  13. Schumann's wheel tachistoscope: its reconstruction and its operation.

    PubMed

    Stock, Armin

    2014-05-01

    In the fall and winter of 1910, Max Wertheimer (1880-1943) performed his famous experiments on perceived motion, published in 1912. Besides slider experiments he mainly used a wheel tachistoscope developed by Friedrich Schumann (1863-1940) at the end of the 19th century. The Adolf-Wuerth-Center for the History of Psychology has several wheel tachistoscopes in its collection of instruments. Their provenance can be traced back to the Institute of Psychology of the University of Frankfurt and the University of Zurich. It is very plausible that Wertheimer, who performed his experiments at the Frankfurt Institute, used one of them. But the wheel tachistoscope alone is not sufficient to reconstruct Wertheimer's original experiments. As always, the devil is in the details. Wertheimer's descriptions of the necessary accessories, a prism, a viewing device, and an electric motor to move the wheel, are rather sparse. This article describes the results of a search for traces in the literature, in archives, and in literary depositories to shed some light on Wertheimer's experimental equipment. As a result, it was possible to reconstruct the entire apparatus and to obtain the same optical impressions with the reconstructed devices as Wertheimer's observers reported. In addition, one of his results was replicated with new participants exactly 100 years after its first publication.

  14. The success story of crystallography.

    PubMed

    Schwarzenbach, Dieter

    2012-01-01

    Diffractionists usually place the birth of crystallography in 1912 with the first X-ray diffraction experiment of Friedrich, Knipping and Laue. This discovery propelled the mathematical branch of mineralogy to global importance and enabled crystal structure determination. Knowledge of the geometrical structure of matter at atomic resolution had revolutionary consequences for all branches of the natural sciences: physics, chemistry, biology, earth sciences and material science. It is scarcely possible for a single person in a single article to trace and appropriately value all of these developments. This article presents the limited, subjective view of its author and a limited selection of references. The bulk of the article covers the history of X-ray structure determination from the NaCl structure to aperiodic structures and macromolecular structures. The theoretical foundations were available by 1920. The subsequent success of crystallography was then due to the development of diffraction equipment, the theory of the solution of the phase problem, symmetry theory and computers. The many structures becoming known called for the development of crystal chemistry and of data banks. Diffuse scattering from disordered structures without and with partial long-range order allows determination of short-range order. Neutron and electron scattering and diffraction are also mentioned.

  15. 'Struensee's memoir on the situation of the King' (1772): Christian VII of Denmark.

    PubMed

    Schioldann, Johan

    2013-06-01

    Christian VII of Denmark (1749-1808) was insane throughout his long reign. The royal physician, Johann Friedrich Struensée (1737-72), usurped his power. In 1771 the King appointed him Privy Cabinet Minister. Struensée revolutionized the whole administration of the Danish-Norwegian kingdom and had an adulterous relationship with the Queen, Caroline Mathilda, George III's sister. In January 1772 he was arrested, sentenced to death for lese-majesty and executed. During his confinement, he wrote a memoir on the King's condition, which he considered to be caused by, or the effect of, masturbation. In 1906 Christiansen interpreted it as a case of dementia praecox, i.e. schizophrenia. It is now suggested that Christian's insanity, like that of George III (his cousin), might have been due to porphyria - the 'royal malady', possibly inherited through his mother, Princess Louise of England or his father, King Frederik V, who died from an illness which retrospectively resembles a case of porphyria. PMID:24573261

  16. THE NEOLIBERAL TURN IN AMERICAN HEALTH CARE.

    PubMed

    Gaffney, Adam

    2015-01-01

    Leaving millions both uninsured and underinsured, the Affordable Care Act does not create a system of universal health care in the United States. To understand its shortcomings, we have to understand it as part of a historic shift in the political economy of American health care. This "neoliberal turn" began as a reaction against the welfare state as it expanded during the New Deal and post-World War II period. What began as a movement associated with philosophers like Friedrich Hayek ultimately had a powerful impact via the attraction of powerful corporate sponsors and political supporters, and it was to historically transform American health care thought and organization. In health policy circles, for example, it can be seen in a rising emphasis on "moral hazard," overuse, and cost sharing above a concern with universalism and equity. It was likewise manifested by the corporatization of the health maintenance organization and the rise of the "consumer-driven" health care movement. By the time of the health care reform debate, the influence of corporate "stakeholders" was to prove predominant. These developments, however, must be construed as connected parts of a much larger political transformation, reflected in rising inequality and privatization, occurring both domestically and internationally.

  17. The metaphor of epigenesis: Kant, Blumenbach and Herder.

    PubMed

    Helbig, Daniela; Nassar, Dalia

    2016-08-01

    Over the last few decades, the meaning of the scientific theory of epigenesis and its significance for Kant's critical philosophy have become increasingly central questions. Most recently, scholars have argued that epigenesis is a key factor in the development of Kant's understanding of reason as self-grounding and self-generating. Building on this work, our claim is that Kant appealed to not just any epigenetic theory, but specifically Johann Friedrich Blumenbach's account of generation, and that this appeal must be understood not only in terms of self-organization, but also in terms of the demarcation of a specific domain of inquiry: for Blumenbach, the study of life; for Kant, the study of reason. We argue that Kant adopted this specific epigenetic model as a result of his dispute with Herder regarding the independence of reason from nature. Blumenbach's conception of epigenesis and his separation of a domain of the living from the non-living lent Kant the tools to demarcate metaphysics, and to guard reason against Herder's attempts to naturalize it. PMID:27474190

  18. Parameter investigation with line-implicit lower-upper symmetric Gauss-Seidel on 3D stretched grids

    NASA Astrophysics Data System (ADS)

    Otero, Evelyn; Eliasson, Peter

    2015-03-01

    An implicit lower-upper symmetric Gauss-Seidel (LU-SGS) solver has been implemented as a multigrid smoother combined with a line-implicit method as an acceleration technique for Reynolds-averaged Navier-Stokes (RANS) simulation on stretched meshes. The computational fluid dynamics code concerned is Edge, an edge-based finite volume Navier-Stokes flow solver for structured and unstructured grids. The paper focuses on the investigation of the parameters related to our novel line-implicit LU-SGS solver for convergence acceleration on 3D RANS meshes. The LU-SGS parameters are defined as the Courant-Friedrichs-Lewy number, the left-hand side dissipation, and the convergence of iterative solution of the linear problem arising from the linearisation of the implicit scheme. The influence of these parameters on the overall convergence is presented and default values are defined for maximum convergence acceleration. The optimised settings are applied to 3D RANS computations for comparison with explicit and line-implicit Runge-Kutta smoothing. For most of the cases, a computing time acceleration of the order of 2 is found depending on the mesh type, namely the boundary layer and the magnitude of residual reduction.

  19. Application of Dey-Mittra conformal boundary algorithm to 3D electromagnetic modeling

    NASA Astrophysics Data System (ADS)

    Nieter, C.; Cary, John R.; Werner, Gregory R.; Smithe, David N.; Stoltz, Peter H.

    2009-11-01

    The Dey-Mittra conformal boundary conditions have been implemented for the finite-difference time-domain (FDTD) electromagnetic solver of the VORPAL plasma simulation framework and studied in the context of three-dimensional, large-scale computations. The maximum stable time step when using these boundary conditions can be arbitrarily small, due to the presence of small fractional cells inside the vacuum region. Use of the Gershgorin Circle theorem allows the determination of a rigorous criterion for exclusion of small cells in order to have numerical stability for particular values of the ratio fDM≡Δt/ΔtCFL of the time step to the Courant-Friedrichs-Lewy value for the infinite system. Application to a spherical cavity shows that these boundary conditions allow computation of frequencies with second-order error for sufficiently small fDM. However, for sufficiently fine resolution, dependent on fDM, the error becomes first order, just like the error for stair-step boundary conditions. Nevertheless, provided one does use a sufficiently small value of fDM, one can obtain third-order accuracy through Richardson extrapolation. Computations for the TESLA superconducting RF cavity design compare favorably with experimental measurements.

  20. [Weizsäcker and Indian philosophy - a new beginning in negotiating the dualism of mind and matter?].

    PubMed

    von Brück, Michael

    2014-01-01

    Carl Friedrich von Weizsäcker's thought is centred around the idea of the unity of reality. He tries to express this idea in his interpretation of quantum physics as well as on the background of neoplatonic thinking. Even his interest in Indian philosophies is based on this concept that would overcome the dualism of mind and matter as well as the dualism of subject and object. On this basis he also tries to reflect on his own inexpressible "mystical" experience in Tiruvannamalai, India, interpreting it with the help of the experience he has been told about by the Indian thinker Gopi Krishna. This is the concept of prana (vital energy) that he uses to find a common terminological ground for physical and mental events. According to Indian Advaita Vedanta, the non-dualistic interpretation of the Vedantic scriptures, reality is based on a non-dual oneness that is self-reflective, transparent and neither immanent nor transcendent but beyond any category. It is pure bliss in its self-expression. Human "mental" experience is a reflective mode of this one reality, subject and object coincide. The result is a holistic psycho-somatology. In view of these ideas Weizsäcker reformulates the notion of "matter". It is less an interaction of particles with specific mass than a non-dual net of interrelations and information, and this would correlate with a concept of mind (consciousness) that could be conceptualized as the energy of self-reflectivity in that very process.

  1. Life and work of E.F.F. Chladni

    NASA Astrophysics Data System (ADS)

    Ullmann, D.

    2007-06-01

    Ernst Florens Friedrich Chladni, the son of the rector of the University of Wittenberg, studied law and philosophy at the Universities of Wittenberg and Leipzig, wrote a dissertation in each of these disciplines and became an experimentalist concerned with sound and vibrations. Chladni's name is associated with the Chladni figures, and this is the first real effort to experimentally investigate the nature of sound. In the lecture the publications of Chladni are presented and, cursorily, his new instruments, designed and built by the physicist. Chladni began to tour half Europe in his own coach with sufficient space for his musical instruments. He gave lectures on the physics of plate and rod vibrations and included demonstrations of the figures and his musical instruments. Chladni's work has had a profound influence on the experimental advances in acoustics, room acoustics, in the verification of theories of superposition of waves, in elasticity, vibrational modes, sound velocities in various media, and much more. The lecture presents a portrait of the scientist Chladni, the times, and his contributions to experimental acoustics which influenced research for many decades.

  2. Variational energy principle for compressible, baroclinic flow. 2: Free-energy form of Hamilton's principle

    NASA Technical Reports Server (NTRS)

    Schmid, L. A.

    1977-01-01

    The first and second variations are calculated for the irreducible form of Hamilton's Principle that involves the minimum number of dependent variables necessary to describe the kinetmatics and thermodynamics of inviscid, compressible, baroclinic flow in a specified gravitational field. The form of the second variation shows that, in the neighborhood of a stationary point that corresponds to physically stable flow, the action integral is a complex saddle surface in parameter space. There exists a form of Hamilton's Principle for which a direct solution of a flow problem is possible. This second form is related to the first by a Friedrichs transformation of the thermodynamic variables. This introduces an extra dependent variable, but the first and second variations are shown to have direct physical significance, namely they are equal to the free energy of fluctuations about the equilibrium flow that satisfies the equations of motion. If this equilibrium flow is physically stable, and if a very weak second order integral constraint on the correlation between the fluctuations of otherwise independent variables is satisfied, then the second variation of the action integral for this free energy form of Hamilton's Principle is positive-definite, so the action integral is a minimum, and can serve as the basis for a direct trail and error solution. The second order integral constraint states that the unavailable energy must be maximum at equilibrium, i.e. the fluctuations must be so correlated as to produce a second order decrease in the total unavailable energy.

  3. Quantum enhancement of vibrational predissociation near the dissociation threshold

    SciTech Connect

    Cote, R.; Dashevskaya, E.I.; Nikitin, E.E.; Troe, J.

    2004-01-01

    We discuss quantum enhancement of the quasiclassical vibrational predissociation (VP) rate of an atom (A)-diatom (BC) van der Waals (vdW) complex A-BC from a state lying close to the dissociation threshold. The enhancement is due to the accumulation of a noticeable fraction of the state population near the outer turning point of the A-BC bond. For potentials behaving as power-laws at large separations, the enhancement manifests itself in the variation of the energy dependence of the VP frequency factor from the classical frequency to its quantum counterpart. We show that it is related to the complex scattering length associated with the vibrational relaxation of BC in collisions with A. We also discuss the corrected quasiclassical quantization condition for energy levels of a diatom lying very close to the dissociation threshold. Our results generalize those of J. Trost, C. Eltshka, and H. Friedrich [J. Phys. B 31, 361 (1998)] and C. Boisseau et al. [Eur. Phys. J. D 12, 199 (2000)] for the calculation of complex energy levels of an anharmonic oscillator that dissociates from highly excited states under the action of a weak high-frequency perturbation.

  4. [Bacteriological findings in materials from patients with nonspecific odontogenic infections].

    PubMed

    Oehring, V H; Schumann, D; Karl, P; Knappe, U; Gruhn, I

    1976-01-01

    The results of bacteriological studies made between 1964 and 1971 by workers at the Varia Laboratory, Institute of Medical Microbiology on 767 patients treated at the Clinic of Gnathofacial Surgery, Department of Medicine, Friedrich Schiller University at Jena, are evaluated. The testees (x=275) were included in groups with specific diagnoses, and a breakdown was made according to the detection of aerobic pus-forming germs. Gram-positive cocci were detected in 92% of the cases and their pathogenetic representatives, 76,5% of the cases. Rodshaped germs (Enterobacteriaceae, Pseudomonas) were observed only in 37,9% of the cases. Staphylococcus aureus, which accounted for 62,5%, was the most frequently observed species. It was followed, in order of frequency of detection, by greening streptococci and Staphylococcus epidermidis. Monoinfection was far more frequently observed than multi-infection. Also, the problems associated with the differentiation of streptococci are pointed out since other investigators found streptococci to be the most frequent agents producing odontogenic infections. PMID:7062

  5. BOOK REVIEW: Astronomie von Olbers bis Schwarzschild. Nationale Entwicklungen und internationale Beziehungen im 19. Jahrhundert (Acta Historica Astronomiae Vol. 16)

    NASA Astrophysics Data System (ADS)

    Sterken, C.; Dick, W. R.; Hamel, J.

    2002-12-01

    The 14th volume of the Acta Historica Astronomiae is the Proceedings of a Colloquium International Relationships in Astronomy (in German) organised by the History of Astronomy Section of the Astronomische Gesellschaft held on September 18 in Lilienthal, Germany. The book contains 13 articles on astronomical topics covering the 19th and 20th centuries. The first paper is by Guenther Oestmann and deals with contemporary assessments of Johann Hieronymus Schroeter's (1745-1816) astronomical works and with later judgements of the scientific importance and significance of his observations as seen by astronomers and historians. This report is complemented by a second article on Schroeter's 25-ft reflector in Lilienthal near Bremen. To this end, author Felix Luehning has constructed a scale model of the telescope, and shows how the building of a model brings a deeper understanding of function and handling of this instrument. This brings us to a third paper on telescope building in Lilienthal: Hans-Joachim Leue describes the cooperation of Johann Hieronymus Schroeter and Johann Gottlieb Schrader in developing a white reflecting metal alloy for use as telescope mirror. The fourth article, by Klaus Schillinger, describes on the basis of archival documents the aquisition history of the Herschel telescopes, including telescope quality check, repair and building. Memorial sites referring to Wilhelm Olbers, Johann Hieronymus Schroeter, Friedrich Wilhelm Bessel and Carl Friedrich Gauss are described by Arno Langkavel in two walks outlined in the very last paper of this book. Peter Brosche, in the fifth paper, discusses the rediscovery of Ceres in December1801, a discovery that was the result of the combined efforts of a theoretician (Gauss) and an observer (Zach). Juergen Hamel's paper is based on previously unused archival sources and discusses the outstanding role played by H. C. Schumacher (1780-1850, editor of the Astronomische Nachrichten) in the communication between

  6. No variations in transit times for Qatar-1 b

    NASA Astrophysics Data System (ADS)

    Maciejewski, G.; Fernández, M.; Aceituno, F. J.; Ohlert, J.; Puchalski, D.; Dimitrov, D.; Seeliger, M.; Kitze, M.; Raetz, St.; Errmann, R.; Gilbert, H.; Pannicke, A.; Schmidt, J.-G.; Neuhäuser, R.

    2015-05-01

    Aims: The transiting hot-Jupiter planet Qatar-1 b exhibits variations in transit times that could be perturbative. A hot Jupiter with a planetary companion on a nearby orbit would constitute an unprecedented planetary configuration, which is important for theories of the formation and evolution of planetary systems. We performed a photometric follow-up campaign to confirm or refute transit timing variations. Methods: We extend the baseline of transit observations by acquiring 18 new transit light curves acquired with 0.6-2.0 m telescopes. These photometric time series, together with data available in the literature, were analyzed in a homogenous way to derive reliable transit parameters and their uncertainties. Results: We show that the dataset of transit times is consistent with a linear ephemeris leaving no hint of any periodic variations with a range of 1 min. We find no compelling evidence of a close-in planetary companion to Qatar-1 b. This finding is in line with a paradigm that hot Jupiters are not components of compact multiplanetary systems. Based on dynamical simulations, we place tighter constraints on the mass of any fictitious nearby planet in the system. Furthermore, new transit light curves allowed us to redetermine system parameters with better precision than reported in previous studies. Our values generally agree with previous determinations. Partly based on (1) data collected with telescopes at the Rozhen National Astronomical Observatory and (2) observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.Tables of light curve data are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/577/A109

  7. Oral Histories in Meteoritics and Planetary Science—XIX: Klaus Keil

    NASA Astrophysics Data System (ADS)

    Sears, Derek W. G.

    2012-12-01

    Abstract- Klaus Keil (Fig. 1) grew up in Jena and became interested in meteorites as a student of Fritz Heide. His research for his Dr. rer. nat. became known to Hans Suess who--with some difficulty--arranged for him to move to La Jolla, via Mainz, 6 months before the borders of East Germany were closed. In La Jolla, Klaus became familiar with the electron microprobe, which has remained a central tool in his research and, with Kurt Fredriksson, he confirmed the existence of Urey and Craig's chemical H and L chondrite groups, and added a third group, the LL chondrites. Klaus then moved to NASA Ames where he established a microprobe laboratory, published his definitive paper on enstatite chondrites, and led in the development of the Si(Li) detector and the EDS method of analysis. After 5 years at Ames, Klaus became director of the Institute of Meteoritics at the University of New Mexico where he built up one of the leading meteorite research groups while working on a wide variety of projects, including chondrite groups, chondrules, differentiated meteorites, lunar samples, and Hawai'ian basalts. The basalt studies led to a love of Hawai'i and a move to the University of Hawai'i in 1990, where he has continued a wide variety of meteorite projects, notably the role of volcanism on asteroids. Klaus Keil has received honorary doctorates from Friedrich-Schiller University, Jena, and the University of New Mexico, Albuquerque. He was President of the Meteoritical Society in 1969-1970 and was awarded the Leonard Medal in 1988.

    Klaus Keil at the University of Hawai'i at Manoa, 2007.

  8. Transit timing variation and activity in the WASP-10 planetary system

    NASA Astrophysics Data System (ADS)

    Maciejewski, G.; Dimitrov, D.; Neuhäuser, R.; Tetzlaff, N.; Niedzielski, A.; Raetz, St.; Chen, W. P.; Walter, F.; Marka, C.; Baar, S.; Krejcová, T.; Budaj, J.; Krushevska, V.; Tachihara, K.; Takahashi, H.; Mugrauer, M.

    2011-02-01

    Transit timing analysis may be an effective method of discovering additional bodies in extrasolar systems that harbour transiting exoplanets. The deviations from the Keplerian motion, caused by mutual gravitational interactions between planets, are expected to generate transit timing variations of transiting exoplanets. In 2009, we collected nine light curves of eight transits of the exoplanet WASP-10b. Combining these data with those published, we have found that transit timing cannot be explained by a constant period but by a periodic variation. Simplified three-body models, which reproduce the observed variations of timing residuals, were identified by numerical simulations. We have found that the configuration with an additional planet with a mass of ˜0.1 MJ and an orbital period of ˜5.23 d, located close to the outer 5 : 3 mean motion resonance, is the most likely scenario. If the second planet is a transiter, the estimated flux drop will be ˜0.3 per cent and can be observed with a ground-based telescope. Moreover, we present evidence that the spots on the stellar surface and the rotation of the star affect the radial-velocity curve, giving rise to a spurious eccentricity of the orbit of the first planet. We argue that the orbit of WASP-10b is essentially circular. Using the gyrochronology method, the host star was found to be 270 ± 80 Myr old. This young age can explain the large radius reported for WASP-10b. Partly based on observations made with the 0.6- and 2.0-m telescopes of the Rozhen National Astronomical Observatory, which is operated by the Institute of Astronomy, Bulgarian Academy of Sciences, and the 90-cm telescope of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich Schiller University.

  9. Integrated Modeling of Satellite Gravity data of Active Plate Margins - Bridging the Gap between Geodesy and Geophysics

    NASA Astrophysics Data System (ADS)

    Hosse, M.; Pail, R.; Mahatsente, R.; Goetze, H.; Jahr, T.; Jentzsch, M.; Gutknecht, B. D.; Koether, N.; Lücke, O.; Sharma, R.; Zeumann, S.

    2011-12-01

    IMOSAGA (Integrated Modeling of Satellite and Airborne Gravity data of Active plate margins) is a joint research project of the Christian-Albrechts-Universität Kiel (Geophysics), Friedrich-Schiller-Universität Jena (Geophysics) and Technische Universität München (Geodesy). It aims to interpret the 3D density and dynamic structure of active convergent plate boundaries of the South and Central American subduction zones using satellite (GOCE, GRACE) and terrestrial gravity data. The density, dynamic and flexural rigidity models based on GOCE gravity, gravity gradients and invariants will add new dimension to the interpretation of lithospheric structure, localization of strain accumulation along plate interface and delineation of regions of high seismic moment release. These objectives shall be achieved using (1) robust data processing which makes GOCE gravity and gravity gradients suitable for geophysical modeling; and (2) well constrained geodynamic modeling of the interaction between the subducting and overriding plates. In this contribution, the impact of GOCE data in the test region of Central America shall be evaluated. GOCE (in combination with GRACE) shall be used on the one hand to validate available, but partly sparsely distributed terrestrial data, and on the other hand to be integrated in a regional combined gravity model for the test area using a collocation approach. By 3D static modeling applying the software IGMAS+, the gravity field will be used to constrain density models of the lithosphere and geodynamic processing in the test area. This provides a full closed-loop, including a source model, model gravity field functionals and actual measurements. By analyzing the results in detail, the sensitivity of GOCE observations to local density variations, and vice versa the impact of GOCE as new observation type for geophysical modeling purposes shall be quantified.

  10. [Tone psychology and music research as catalysts of experimental-scientific practice and methodology in the circle of Carl Stumpf].

    PubMed

    Klotz, Sebastian

    2008-09-01

    The study of acoustics, harmonics and of music has been providing scientific models since Greek Antiquity. Since the early modern ages, two separate cultures began to emerge out of the study of music: a technical acoustics and an aesthetically and philosophically inspired musical criticism. In the writings of Johann Friedrich Herbart (1811) a scientific approach to musical aesthetics and to music perception is taking shape that reinstalls the listening process as a highly complex and logical phenomenon. By opening music for a scientific psychological investigation, Herbart pioneered the physiologically and acoustically grounded seminal work by Hermann von Helmholtz On the sensations of tone (1863) which the author considered a prerequisite for musical aesthetics and music theory. Helmholtz in turn inspired the philosopher and psychologist Carl Stumpf to further investigate musical perception (beginning in 1883). To Stumpf, it provided a paradigm for experimental psychology as mental functions and phenomena could be studied in detail. These functions and phenomena are the actual objects of scientific study in Stumpf's inductive and descriptive psychology. Combining insights from statistics, ethnology, anthropology, psychoacoustics and the cultural history of mankind, Stumpf and his team developed a new blend of science which absorbs styles of reasoning, analytical procedures and academic convictions from natural history, the natural sciences and the humanities but at the same time identifies shortcomings of these approaches that fail to grasp the complexities of psychic functions. Despite their reliance on the quasi-objective phonograph and despite their commitment to objectivity, precision and measurement, mental phenomena relating to tonal perception and to music provided too complex a challenge to be easily articulated and shared by the scientific community after 1900. The essay illustrates these tensions against the background of a history of objectivity.

  11. Shock-capturing approach and nonevolutionary solutions in magnetohydrodynamics

    SciTech Connect

    Barmin, A.A.; Kulikovskiy, A.G.; Pogorelov, N.V.

    1996-06-01

    Shock-capturing methods have become an effective tool for the solution of hyperbolic partial differential equations. Both upwind and symmetric TVD schemes in the framework of the shock-capturing approach are thoroughly investigated and applied with great success to a number of complicated multidimensional gasdynamic problems. The extension of these schemes to magnetohydrodynamic (MHD) equations is not a simple task. First, the exact solution of the MHD Riemann problem is too multivariant to be used in regular calculations. On the other hand, the extensions of Roe`s approximate Riemann problem solvers for MHD equations in general case are nonunique and need further investigation. That is why, some simplified approaches should be constructed. In this work, the second order of accuracy in time and space high-resolution Lax-Friedrichs type scheme is suggested that gives a drastic simplification of the numerical algorithm comparing to the precise characteristic splitting of Jacobian matrices. The necessity is shown to solve the full set of MHD equations for modeling of multishocked flows, even when the problem is axisymmetric, to obtain evolutionary solutions. for the numerical example, the MHD Riemann problem is used with the initial data consisting of two constant states lying to the right and to the left from the centerline of the computational domain. If the problem is solved as purely coplanar, a slow compound wave appears in the self-similar solution obtained by any shock-capturing scheme. If the full set of MHD equations is used and a small uniform tangential disturbance is added to the magnetic field vector, a rotational jump splits from the compound wave, and it degrades into a slow shock. The reconstruction process of the nonevolutionary compound wave into evolutionary shocks is investigated. Presented results should be taken into account in the development of shock-capturing methods for MHD flows. 18 refs., 17 figs.

  12. Magneto-frictional Modeling of Coronal Nonlinear Force-free Fields. I. Testing with Analytic Solutions

    NASA Astrophysics Data System (ADS)

    Guo, Y.; Xia, C.; Keppens, R.; Valori, G.

    2016-09-01

    We report our implementation of the magneto-frictional method in the Message Passing Interface Adaptive Mesh Refinement Versatile Advection Code (MPI-AMRVAC). The method aims at applications where local adaptive mesh refinement (AMR) is essential to make follow-up dynamical modeling affordable. We quantify its performance in both domain-decomposed uniform grids and block-adaptive AMR computations, using all frequently employed force-free, divergence-free, and other vector comparison metrics. As test cases, we revisit the semi-analytic solution of Low and Lou in both Cartesian and spherical geometries, along with the topologically challenging Titov-Démoulin model. We compare different combinations of spatial and temporal discretizations, and find that the fourth-order central difference with a local Lax-Friedrichs dissipation term in a single-step marching scheme is an optimal combination. The initial condition is provided by the potential field, which is the potential field source surface model in spherical geometry. Various boundary conditions are adopted, ranging from fully prescribed cases where all boundaries are assigned with the semi-analytic models, to solar-like cases where only the magnetic field at the bottom is known. Our results demonstrate that all the metrics compare favorably to previous works in both Cartesian and spherical coordinates. Cases with several AMR levels perform in accordance with their effective resolutions. The magneto-frictional method in MPI-AMRVAC allows us to model a region of interest with high spatial resolution and large field of view simultaneously, as required by observation-constrained extrapolations using vector data provided with modern instruments. The applications of the magneto-frictional method to observations are shown in an accompanying paper.

  13. ["Fiction and Truth": Goethe's anatomical research at the University of Jena].

    PubMed

    Schäfer, H H; Sivukhina, E; Dölz, W; Oehring, H

    2012-12-01

    Johann Wolfgang von Goethe was one of the most renowned German poets of the late Age of Enlightenment. However, his engagement went far beyond literature especially relating to politics and natural science. Goethe, primarily trained as a lawyer, developed his own theory of colors and even challenged the concepts of Isaac Newton. His discovery of the human intermaxilary bone questioned all the dogmas of the religious-minded world of the 18th century. Together with the anatomy professor Justus Christian Loder, Goethe performed comparative anatomy and proved the conceptual uniformity of humans and animals on 27 March 1784. Even though, Félix Vicq d'Azyr described the intermaxilary bone simultaneously in Catholic France, Goethe's findings were politically accepted due to the liberal Protestantism of the Duchy of Weimar. Nevertheless, leading anatomists of the century (Johann Friedrich Blumenbach, Petrus Camper and Samuel Thomas v. Soemmerring) mainly rejected Goethe's postulates which led to a delayed publication in 1820; almost 36 years after writing his original manuscript. Today, Goethe's discovery is known to be a fundamental basis for the development of Charles Darwin's theory of phylogenetic evolution. Nowadays, the Department of Anatomy contains the Museum Anatomicum Jenense which was founded by the Duke of Weimar, Carl August and Goethe and entails Goethe's premaxillary bones as its main attraction. The University values the cultural heritage of Goethe's contribution to Medicine and provides access to the collection to the public and generations of medical students. Still today Goethe's legacy is noticeable in the halls of the Alma Mater Jenensis.

  14. History of the Munich-Maisach-Fürstenfeldbruck Geomagnetic Observatory

    NASA Astrophysics Data System (ADS)

    Soffel, H. C.

    2015-07-01

    The Munich-Maisach-Fürstenfeldbruck Geomagnetic Observatory is one of the observatories with the longest recordings of the geomagnetic field. It started with hourly measurements on 1 August 1840. The founder of the observatory in Munich was Johann von Lamont (1805-1879), the Director of the Royal Bavarian Astronomical Observatory. He had been stimulated to build his own observatory by the initiative of the Göttingen Magnetic Union founded in 1834 by Alexander von Humboldt (1769-1859) and Carl Friedrich Gauss (1777-1855). Before 1840 fewer than five observatories existed; the most prominent ones were those in London and Paris. At the beginning Lamont used equipment delivered by Gauss in Göttingen, but soon started to build instruments of his own design. Among them was a nonmagnetic theodolite which allowed precise geomagnetic measurements to be made also in the field. During the 1850s Lamont carried out geomagnetic surveys and produced geomagnetic maps for Germany and many other European countries. At the end of the nineteenth century accurate geomagnetic measurements in Munich became more and more disturbed by the magnetic stray fields from electric tramways and industry. During this period the quality of the data suffered and the measurements had to be interrupted several times. After a provisional solution in Maisach, a village 25 km west of Munich, a final solution could be found in the vicinity of the nearby city of Fürstenfeldbruck. Here the measurements started again on 1 January 1939. Since the 1980s the observatory has been part of INTERMAGNET, an organization providing almost real-time geomagnetic data of the highest quality.

  15. A fully implicit dynamo model for long-term evolution of the geomagnetic field

    NASA Astrophysics Data System (ADS)

    Zhan, X.; Chen, R.; Cai, X. C.; Zhang, K.

    2014-12-01

    In this work, we present a Newton-Krylov-Schwarz (NKS) based parallel implicit solver for the governing equations of Earth's dynamo. NKS is a general purpose parallel solver for nonlinear systems and has been widely applied to solve different kinds of nonlinear problems. All previously published dynamo models treat nonlinear terms of dynamo governing equations in an explicit or semi-explicit manner, consequently, the numerical schemes are constrained by the Courant-Friedrichs-Lewy (CFL) condition. To ensure numerical stability, time step sizes should be rather small, especially for high-resolution dynamo simulations, which makes it impractical to use high-resolution dynamo models to study long term evolution of the geomagnetic field, such as reversals and superchrons. To avoid the time step size constraint imposed by CFL numbers associated with fine spacial mesh sizes, we try a fully implicit method and focus on efficiently solving the large nonlinear system at each time step on large scale parallel computers. Our algorithm begins with a discretization of the governing equations on an unstructured tetrahedron mesh with a stable finite element method in space and a fully implicit backward difference scheme in time. At each time step, an inexact Newton method is employed to solve the discretized large sparse nonlinear system while in the Newton steps, a domain decomposition preconditioned Krylov method is used to solve the Jacobian system which is constructed analytically in order to obtain the desired performance. Our numerical model is tested against known standard dynamo solutions at a moderate Ekman number. Additionally, numerical experiments show that our model has super-linear scalability with over eight thousand processors for dynamo problems with tens of millions of unknowns.

  16. Magneto-frictional Modeling of Coronal Nonlinear Force-free Fields. I. Testing with Analytic Solutions

    NASA Astrophysics Data System (ADS)

    Guo, Y.; Xia, C.; Keppens, R.; Valori, G.

    2016-09-01

    We report our implementation of the magneto-frictional method in the Message Passing Interface Adaptive Mesh Refinement Versatile Advection Code (MPI-AMRVAC). The method aims at applications where local adaptive mesh refinement (AMR) is essential to make follow-up dynamical modeling affordable. We quantify its performance in both domain-decomposed uniform grids and block-adaptive AMR computations, using all frequently employed force-free, divergence-free, and other vector comparison metrics. As test cases, we revisit the semi-analytic solution of Low and Lou in both Cartesian and spherical geometries, along with the topologically challenging Titov–Démoulin model. We compare different combinations of spatial and temporal discretizations, and find that the fourth-order central difference with a local Lax–Friedrichs dissipation term in a single-step marching scheme is an optimal combination. The initial condition is provided by the potential field, which is the potential field source surface model in spherical geometry. Various boundary conditions are adopted, ranging from fully prescribed cases where all boundaries are assigned with the semi-analytic models, to solar-like cases where only the magnetic field at the bottom is known. Our results demonstrate that all the metrics compare favorably to previous works in both Cartesian and spherical coordinates. Cases with several AMR levels perform in accordance with their effective resolutions. The magneto-frictional method in MPI-AMRVAC allows us to model a region of interest with high spatial resolution and large field of view simultaneously, as required by observation-constrained extrapolations using vector data provided with modern instruments. The applications of the magneto-frictional method to observations are shown in an accompanying paper.

  17. A Class of High-Resolution Explicit and Implicit Shock-Capturing Methods

    NASA Technical Reports Server (NTRS)

    Yee, H. C.

    1994-01-01

    The development of shock-capturing finite difference methods for hyperbolic conservation laws has been a rapidly growing area for the last decade. Many of the fundamental concepts, state-of-the-art developments and applications to fluid dynamics problems can only be found in meeting proceedings, scientific journals and internal reports. This paper attempts to give a unified and generalized formulation of a class of high-resolution, explicit and implicit shock capturing methods, and to illustrate their versatility in various steady and unsteady complex shock waves, perfect gases, equilibrium real gases and nonequilibrium flow computations. These numerical methods are formulated for the purpose of ease and efficient implementation into a practical computer code. The various constructions of high-resolution shock-capturing methods fall nicely into the present framework and a computer code can be implemented with the various methods as separate modules. Included is a systematic overview of the basic design principle of the various related numerical methods. Special emphasis will be on the construction of the basic nonlinear, spatially second and third-order schemes for nonlinear scalar hyperbolic conservation laws and the methods of extending these nonlinear scalar schemes to nonlinear systems via the approximate Riemann solvers and flux-vector splitting approaches. Generalization of these methods to efficiently include real gases and large systems of nonequilibrium flows will be discussed. Some perbolic conservation laws to problems containing stiff source terms and terms and shock waves are also included. The performance of some of these schemes is illustrated by numerical examples for one-, two- and three-dimensional gas-dynamics problems. The use of the Lax-Friedrichs numerical flux to obtain high-resolution shock-capturing schemes is generalized. This method can be extended to nonlinear systems of equations without the use of Riemann solvers or flux

  18. Average-State Jacobians and Implicit Methods for Compressible Viscous and Turbulent Flows

    NASA Astrophysics Data System (ADS)

    Batten, P.; Leschziner, M. A.; Goldberg, U. C.

    1997-10-01

    Several new implicit schemes for the solution of the compressible Navier-Stokes equations are presented. These methods are derived from a hierarchy of average-state approximate solutions to the Riemann problem, ranging from the Lax-Friedrichs flux to the exact Riemann-solver flux. In contrast to linearised approximations, these methods will (with certain provisos on the signal velocities) enforce the entropy condition and preserve positivity without the need for additional corrections. The hierarchy also encompasses and explains the origin of many other upwind and centred methods, including the space-time scheme (due to Chang) and the more recent FORCE scheme (due to Toro). Based on an analysis of the above hierarchy, attention is focussed on the development of a new implicit scheme using a positivity-preserving version of Toro et al.'s HLLC scheme, which is the simplest average-state solver capable of exactly preserving isolated shock, contact, and shear waves. Solutions obtained with this method are essentially indistinguishable from those produced with an exact Riemann solver, whilst convergence to the steady state is the most rapid of all the implicit average-stage schemes considered and directly comparable to that of the unmodified Roe scheme. A new two-step implicit method is applied to various test cases, including turbulent flow with shock/boundary-layer interaction. The new time-stepping scheme is composed of two backward Euler steps, but has twice the convergence rate of the backward Euler scheme and alleviates the convergence problems that are often experienced when employing compressive limiter functions.

  19. An optimal modeling of multidimensional wave digital filtering network for free vibration analysis of symmetrically laminated composite FSDT plates

    NASA Astrophysics Data System (ADS)

    Tseng, Chien-Hsun

    2015-02-01

    The technique of multidimensional wave digital filtering (MDWDF) that builds on traveling wave formulation of lumped electrical elements, is successfully implemented on the study of dynamic responses of symmetrically laminated composite plate based on the first order shear deformation theory. The philosophy applied for the first time in this laminate mechanics relies on integration of certain principles involving modeling and simulation, circuit theory, and MD digital signal processing to provide a great variety of outstanding features. Especially benefited by the conservation of passivity gives rise to a nonlinear programming problem (NLP) for the issue of numerical stability of a MD discrete system. Adopting the augmented Lagrangian genetic algorithm, an effective optimization technique for rapidly achieving solution spaces of NLP models, numerical stability of the MDWDF network is well received at all time by the satisfaction of the Courant-Friedrichs-Levy stability criterion with the least restriction. In particular, optimum of the NLP has led to the optimality of the network in terms of effectively and accurately predicting the desired fundamental frequency, and thus to give an insight into the robustness of the network by looking at the distribution of system energies. To further explore the application of the optimum network, more numerical examples are engaged in efforts to achieve a qualitative understanding of the behavior of the laminar system. These are carried out by investigating various effects based on different stacking sequences, stiffness and span-to-thickness ratios, mode shapes and boundary conditions. Results are scrupulously validated by cross referencing with early published works, which show that the present method is in excellent agreement with other numerical and analytical methods.

  20. Grundsätze über die Anlagen neuer Sternwarten mit Beziehung auf die Sternwarte der Universität Göttingen. Von Georg Heinrich Borheck

    NASA Astrophysics Data System (ADS)

    Beuermann, Klaus; Borheck, Georg Heinrich

    Die Göttinger Sternwarte, Wirkungsstätte des berühmten Gelehrten Carl Friedrich Gauß, ist ein bedeutendes Baudenkmal. Im Jahre 2005 wird sie gemeinsam von der Georg-August-Universität und der Akademie der Wissenschaften zu Göttingen renoviert, um dann als repräsentatives Gebäude der Universität und Arbeitsstätte der Akademie zu dienen. Die Nutzung der historischen Räume für Ausstellungen macht diesen imposanten Bau erstmals der Öffentlichkeit zugänglich. Die Sternwarte war bei ihrer Errichtung vor 200 Jahren ein nach seinerzeit neuesten wissenschaftlichen Erkenntnissen konzipierter Bau, der die Universität Göttingen in eine der vordersten Stellen Europa rückte. Auch aufgrund ihrer Architektur ist sie ein großer Wurf des Göttinger Universitätsbaumeisters Georg Heinrich Borheck. Durch die Kriegswirren der Napoleonischen Zeit zerschlug sich Borhecks Versuch einer Publikation seiner Beschreibung des Baus der Göttinger Sternwarte 1805. Doch seine Schrift ist auch heute noch aktuell und wird mit diesem Band erstmals einer breiten Öffentlichkeit zugängig gemacht. Er zeigt die Grundsätze, nach denen damals öffentliche Bauten konzipiert wurden, erläutert die Bedeutung des Baus aus kunst- und wissenschaftshistorischer Sicht und informiert über die Pläne zur Restaurierung der Sternwarte in einem separaten Beitrag und im Geleitwort des Präsidenten der Georg-August Universität Prof. Dr. Dr. h. c. Kurt von Figura.

  1. A Detector Radioactive Particles Can't Evade

    SciTech Connect

    Hazi, A U

    2007-02-12

    As part of its national security mission, Lawrence Livermore develops technologies to help government agencies prevent terrorists from smuggling nuclear materials into the country. One ongoing effort is to design radiation detectors that can distinguish threat sources from legitimate sources, such as medical isotopes, and naturally occurring radiation. (See S&TR, September 2004, pp. 4-11; May 2006, pp. 4-10.) Detectors intended for use by nonspecialists must be easy to operate and require minimal maintenance. To be most effective, they also must detect both gamma and neutron energies. That may sound like a lot to ask of one instrument, but the Ultrahigh-Resolution Gamma and Neutron Spectrometer (UltraSpec) delivers all of these features. UltraSpec is so sensitive that even the minute thermal energy deposited by a single gamma ray or neutron can be detected with high precision. With this capability, the detector can identify differences in composition that help reveal a material's origin, processing history, and likely intended use. In addition to its application as a counterterrorism technology, UltraSpec can be used to protect nuclear material stored at nuclear power plants, to evaluate weapon stockpiles, and to verify material composition. UltraSpec was developed by a team of scientists and engineers from Livermore's Physics and Advanced Technologies and Engineering directorates working with VeriCold Technologies of Ismaning, Germany. The detector's design builds on a technology base established in three Laboratory Directed Research and Development projects. The UltraSpec team, which is led by Laboratory physicist Stephan Friedrich, received a 2006 R&D 100 Award for the detector's innovative design.

  2. On further generalization of the rigidity theorem for spacetimes with a stationary event horizon or a compact Cauchy horizon

    NASA Astrophysics Data System (ADS)

    Rácz, István

    2000-01-01

    A rigidity theorem that applies to smooth electrovacuum spacetimes which represent either (A) an asymptotically flat stationary black hole or (B) a cosmological spacetime with a compact Cauchy horizon ruled by closed null geodesics was given in a recent paper by Friedrich et al (1999 Commun. Math. Phys. 204 691-707). Here we enlarge the framework of the corresponding investigations by allowing the presence of other types of matter fields. In the first part the matter fields are involved merely implicitly via the assumption that the dominant energy condition is satisfied. In the second part Einstein-Klein-Gordon (EKG), Einstein-[non-Abelian]-Higgs (E[nA]H), Einstein-[Maxwell]-Yang-Mills-dilaton (E[M]YMd) and Einstein-Yang-Mills-Higgs (EYMH) systems are studied. The black hole event horizon or, respectively, the compact Cauchy horizon of the considered spacetimes is assumed to be a smooth non-degenerate null hypersurface. It is proved that there exists a Killing vector field in a one-sided neighbourhood of the horizon in EKG, E[nA]H, E[M]YMd and EYMH spacetimes. This Killing vector field is normal to the horizon, moreover, the associated matter fields are also shown to be invariant with respect to it. The presented results provide generalizations of the rigidity theorems of Hawking (for case A) and of Moncrief and Isenberg (for case B) and, in turn, they strengthen the validity of both the black hole rigidity scenario and the strong cosmic censor conjecture of classical general relativity.

  3. High-Order Space-Time Methods for Conservation Laws

    NASA Technical Reports Server (NTRS)

    Huynh, H. T.

    2013-01-01

    Current high-order methods such as discontinuous Galerkin and/or flux reconstruction can provide effective discretization for the spatial derivatives. Together with a time discretization, such methods result in either too small a time step size in the case of an explicit scheme or a very large system in the case of an implicit one. To tackle these problems, two new high-order space-time schemes for conservation laws are introduced: the first is explicit and the second, implicit. The explicit method here, also called the moment scheme, achieves a Courant-Friedrichs-Lewy (CFL) condition of 1 for the case of one-spatial dimension regardless of the degree of the polynomial approximation. (For standard explicit methods, if the spatial approximation is of degree p, then the time step sizes are typically proportional to 1/p(exp 2)). Fourier analyses for the one and two-dimensional cases are carried out. The property of super accuracy (or super convergence) is discussed. The implicit method is a simplified but optimal version of the discontinuous Galerkin scheme applied to time. It reduces to a collocation implicit Runge-Kutta (RK) method for ordinary differential equations (ODE) called Radau IIA. The explicit and implicit schemes are closely related since they employ the same intermediate time levels, and the former can serve as a key building block in an iterative procedure for the latter. A limiting technique for the piecewise linear scheme is also discussed. The technique can suppress oscillations near a discontinuity while preserving accuracy near extrema. Preliminary numerical results are shown

  4. The versatile August Bier (1861-1949), father of spinal anesthesia.

    PubMed

    Goerig, M; Agarwal, K; Schulte am Esch, J

    2000-11-01

    "A professor is a gentleman with a different point of view." This characteristic and sarcastic statement was often recited by August Bier (1861-1949) and can also be aptly applied to him. As the father of spinal and intravenous regional neural blockade, Bier had a tremendous impact on surgery and anesthesia. It took him only two years to become a senior lecturer in surgery (so-called "Habilitation") under the guidance of Friedrich von Esmarch. In 1899, he was appointed chairman of the Department of Surgery at the University of Greifswald. From there, he moved to the University of Bonn in 1903 and then succeeded Ernst von Bergmann in Berlin in 1907. Bier's interest in the philosophical theories of Hippocrates and Heraclitus had a significant influence on his outlook on medical practice. His surgical colleagues disapproved of this and his interest in homeopathy. On the other hand, he earned much respect as the co-author of a surgical textbook, i.e., Chirurgische Operationslehre (Operative Surgery). He had a remarkable breadth of nonmedical interests, including philosophy and forestry, and the ideas he expressed are viable even today. His publications on philosophical subjects are as up to date as his concepts in forestry. In 1932, Bier finally decided to retire, although by then he was no longer operating. From that time on, he lived out his days at his estate in Sauen, and he died in 1949 at the age of 88. In this paper we describe some previously unknown aspects of Bier's work in both surgery and research; anesthesiologists and their patients are the beneficiaries of two other of his inventions, namely, spinal and IV local anesthesia. Unfortunately, it is not possible to acknowledge all the innovations of this ingenious surgeon, who truly deserved the description "A professor is a gentleman with a different point of view." PMID:11137420

  5. [Fifty years ago, the double helix gave birth to molecular biology].

    PubMed

    Lunardi, J

    2003-01-01

    Fifty years ago, a paper signed by two young scientists, James Watson and Francis Crick, and reporting a model for DNA based on a double helix structure was published in the scientific review Nature in date of april 25, 1953. Although this model of striking simplicity and rare elegance was actually worked out in a few months by the two men, it was the result of quite 100 years of research aimed at the definition of the structure of the genetic material present in living organisms. The double helix was the outcome of a multidisciplinary approach initiated in the mid 19th century by the genetic laws of Gregor Mendel and the discovery of the chemical nature of the desoxyribonucleic acid by Johann Friedrich Miesher. The discovery of the DNA structure had been at the origin of major scientific progress regarding mechanisms that rule the replication and the expression of the genetic information. Theses researches have given birth to a new scientific field, molecular biology, which everyone will see very soon is actually part in a quasi symbiotic manner of all other biological fields dealing with life. The spectacular development of molecular biology during the last fifty years was in great part possible thanks to a concomitant enormous development of the different methods of investigation of the biological molecules and structure. The present rising of biotechnology applications is the direct consequence of the tremendous amount of fundamental knowledge gained during the last few decennia. They open very important and attractive perspectives both on medical or on socio-economic point of views. There is no doubt that the next fifty years will be as fruitful as the last ones.

  6. A two-column formalism for time-dependent modelling of stellar convection. I. Description of the method

    NASA Astrophysics Data System (ADS)

    Stökl, A.

    2008-11-01

    Context: In spite of all the advances in multi-dimensional hydrodynamics, investigations of stellar evolution and stellar pulsations still depend on one-dimensional computations. This paper devises an alternative to the mixing-length theory or turbulence models usually adopted in modelling convective transport in such studies. Aims: The present work attempts to develop a time-dependent description of convection, which reflects the essential physics of convection and that is only moderately dependent on numerical parameters and far less time consuming than existing multi-dimensional hydrodynamics computations. Methods: Assuming that the most extensive convective patterns generate the majority of convective transport, the convective velocity field is described using two parallel, radial columns to represent up- and downstream flows. Horizontal exchange, in the form of fluid flow and radiation, over their connecting interface couples the two columns and allows a simple circulating motion. The main parameters of this convective description have straightforward geometrical meanings, namely the diameter of the columns (corresponding to the size of the convective cells) and the ratio of the cross-section between up- and downdrafts. For this geometrical setup, the time-dependent solution of the equations of radiation hydrodynamics is computed from an implicit scheme that has the advantage of being unaffected by the Courant-Friedrichs-Lewy time-step limit. This implementation is part of the TAPIR-Code (short for The adaptive, implicit RHD-Code). Results: To demonstrate the approach, results for convection zones in Cepheids are presented. The convective energy transport and convective velocities agree with expectations for Cepheids and the scheme reproduces both the kinetic energy flux and convective overshoot. A study of the parameter influence shows that the type of solution derived for these stars is in fact fairly robust with respect to the constitutive numerical

  7. [Carl Gillmeister: the first Doctor of veterinary medicine in Mecklenburg--and in Germany (1834)].

    PubMed

    Kuhlmann, W; Schäffer, J

    2004-02-01

    German schools and faculties of veterinary medicine did not receive the sovereign right to award the degree "Doctor medicinae veterinarae" until the early twentieth century. Until then, in the nineteenth century there were two possibilities for veterinarians to earn a doctoral degree, usually referred to as the title of "Doctor": 1. On the basis of an exceptionally excellent dissertation and after very stringent examination a candidate could be awarded the degree "Dr. med." by the faculty of a medical school, or, if the candidate had studied at a philosophical faculty, the degree "Dr. phil." 2. A doctoral degree specifically in veterinary medicine could be earned only at a medical faculty. The Medical Faculty of the University of Giessen awarded the degree "Doctor in arte veterinaria" for the first time in 1832. In this study we prove that Giessen was not the first German university to award a doctorate in veterinary medicine, a priority which has never been questioned in the literature. As early as 1829, veterinarians could earn the degree "Doctor artis veterinariae" at the Medical Faculty of the University of Rostock, where three such awards are documented between 1829 and 1831. The designation "medicina" was also intially avoided in Rostock. Therefore, of particular significance is the discovery of a fourth such document from the Rostock University Archives, the doctoral diploma of Carl Jacob Friedrich Gillmeister, who at the age of 22 was awarded the degree "Doctor medicinae veterinariae" in Rostock after a successful defense. This is the earliest, but also the last archival record of the German doctoral degree in veterinary medicine in the modern sense, because after Gillmeister no veterinarian could earn a doctoral degree in Rostock further more. Gillmeisters vita sheds light on the times and the difficulties of the veterinary profession in the poor agricultural area of Mecklenburg. PMID:15032266

  8. Liver growth factor as a tissue regenerating factor in neurodegenerative diseases.

    PubMed

    Gonzalo-Gobernado, Rafael; Calatrava-Ferreras, Lucia; Perucho, Juan; Reimers, Diana; Casarejos, MarIa J; Herranz, Antonio S; Jimenez-Escrig, Adriano; Diaz-Gil, Juan J; Bazan, Eulalia

    2014-01-01

    Liver growth factor (LGF) is a hepatic mitogen purified by our group in 1986. In the following years we demonstrated its activity both in "in vivo" and "in vitro" systems, stimulating hepatocytes mitogenesis as well as liver regeneration in several models of liver injury. Furthermore, we established its chemical composition (albumin-bilirubin complex) and its mitogenic actions in liver. From 2000 onwards we used LGF as a tissue regenerating factor in several models of extrahepatic diseases. The use of Liver growth factor as a neural tissue regenerator has been recently protected (Patent No US 2014/8,642,551 B2). LGF administration stimulates neurogenesis and neuron survival, promotes migration of newly generated neurons, and induces the outgrowth of striatal dopaminergic terminals in 6-hidroxydopamine-lesioned rats. Furthermore, LGF treatment raises striatal dopamine levels and protects dopaminergic neurons in hemiparkinsonian animals. LGF also stimulates survival of grafted foetal neural stem cells in the damaged striatum, reduces rotational behaviour and improves motor coordination. Interestingly, LGF also exerts a neuroprotective role both in an experimental model of cerebellar ataxia and in a model of Friedrich´s ataxia. Microglia seem to be the cellular target of LGF in the CNS. Moreover, the activity of the factor could be mediated by the stimulation of MAPK´s signalling pathway and by regulating critical proteins for cell survival, such as Bcl-2 and phospho-CREB. Since the factor shows neuroprotective and neurorestorative effects we propose LGF as a patented novel therapeutic tool that may be useful for the treatment of Parkinson´s disease and cerebellar ataxias. Currently, our studies have been extended to other neurological disorders such as Alzheimer's disease (Patent No: US 2014/0113859 A1). PMID:25537484

  9. Diagnostic accuracy of APRI, FIB-4 and Forns for the detection of liver cirrhosis in HIV/HCV-coinfected patients.

    PubMed

    Merli, Marco; Castagna, Antonella; Salpietro, Stefania; Gianotti, Nicola; Messina, Emanuela; Poli, Andrea; Morsica, Giulia; Bagaglio, Sabrina; Cernuschi, Massimo; Bigoloni, Alba; Uberti-Foppa, Caterina; Lazzarin, Adriano; Hasson, Hamid

    2016-04-01

    Non-invasive assessment of liver fibrosis represents an appealing method to monitor liver disease in HCV-infected patients. Currently, transient elastography (TE) is the most accurate non-invasive tool to measure liver stiffness (LS), with the diagnostic accuracy increasing together with the stage of fibrosis (Friedrich Rust et al., 2008; Degos et al., 2010). Stiffness measurement is widely used in the assessment of fibrosis in patients with chronic hepatitis C given its good reproducibility (Fraquelli et al., 2007) and its association with the risk of liver-related complications and death in HIV/HCV-coinfected patients (Fernandez-Montero et al., 2013) and also in patients with compensated HCV-related liver cirrhosis (with or without concomitant HIV-coinfection) (Pérez-Latorre et al., 2014). In the last decade, direct and indirect biomarkers for predicting liver fibrosis have also been developed. Direct fibrosis biomarkers (e.g. FibroTest, FibroMeter) are calculated using serum molecules produced in the presence of liver fibrosis and released in the circulatory system while indirect biomarkers (e.g. APRI, FIB-4, Forns) result from the combination of routine blood tests. Even though indirect biomarkers had a lower diagnostic performance than direct biomarkers and especially TE (Sánchez-Conde et al., 2010; Degos et al., 2010; Castéra et al., 2014), the absence of additional costs and the ready availability make indirect biomarkers a quick and easy non-invasive method to periodically assess liver fibrosis. Since the early detection of liver cirrhosis has a significant impact on both clinical management and treatment decision regarding chronic hepatitis C, we evaluated the threshold and the diagnostic accuracy of APRI, FIB-4 and Forns for the diagnosis of liver cirrhosis in HIV/HCV-coinfected patients. PMID:27196548

  10. Mechanistic aspects of the solid-state transformation of ammonium cyanate to urea at high pressure.

    PubMed

    Méreau, Raphael; Desmedt, Arnaud; Harris, Kenneth D M

    2007-04-19

    The chemical transformation of ammonium cyanate into urea has been of interest to many generations of scientists since its discovery by Friedrich Wöhler in 1828. Although widely studied both experimentally and theoretically, several mechanistic aspects of this reaction remain to be understood. In this paper, we apply computational methods to investigate the behavior of ammonium cyanate in the solid state under high pressure, employing a theoretical approach based on the self-consistent-charges density-functional tight-binding method (SCC-DFTB). The ammonium cyanate crystal structure was relaxed under external pressure ranging from 0 to 700 GPa, leading to the identification of five structural phases. Significantly, the phase at highest pressure (above 535 GPa) corresponds to the formation of urea molecules. At ca. 25 GPa, there is a phase transition of ammonium cyanate (from tetragonal P4/nmm to monoclinic P21/m) involving a rearrangement of the ammonium cyanate molecules. This transformation is critical for the subsequent transformation to urea. The crystalline phase of urea obtained above 535 GPa also has P21/m symmetry (Z = 2). This polymorph of urea has never been reported previously. Comparisons to the known (tetragonal) polymorph of urea found experimentally at ambient pressure suggests that the new polymorph is more stable above ca. 8 GPa. Our computational studies show that the transformation of ammonium cyanate into urea is strongly exothermic (enthalpy change -170 kJ mol-1 per formula unit between 530 and 535 GPa). The proposed mechanism for this transformation involves the transfer of two hydrogen atoms of the ammonium cation toward nitrogen atoms of neighboring cyanate anions, and the remaining NH2 group creates a C-NH2 bond with the cyanate unit. PMID:17388562

  11. Abraham Pais Prize Talk: The Joy of History

    NASA Astrophysics Data System (ADS)

    Stuewer, Roger H.

    2013-04-01

    Physicists and historians of physics share a common goal, the quest for understanding, but their objects are different: Physicists attempt to understand Nature, while historians attempt to understand the past, finding both the challenge and joy of history in exploring the contingencies of historical events, their dependence on scientific, biographical, sociopolitical, cultural, and other factors, and shaping them into a coherent narrative. My first example will focus on the history of the photon concept, in particular on the work of Arthur Holly Compton between 1916 and 1922 that led to his discovery of the Compton effect, whose understanding ultimately rested on a close examination of his laboratory notebooks. I will then turn to two episodes in the history of nuclear physics. The first deals with a controversy between 1922 and 1927 between Ernest Rutherford and James Chadwick at the Cavendish Laboratory in Cambridge and Hans Pettersson and Gerhard Kirsch at the Institute for Radium Research in Vienna that involved their fundamentally different experimental observations and theoretical interpretations of the artificial disintegration of nuclei whose resolution could only be understood after uncovering crucial correspondence between the protagonists. The second episode traces George Gamow's creation and development of the liquid-drop model of the nucleus in 1928 and 1929 and its subsequent development in two stages, first by Werner Heisenberg and Carl Friedrich von Weizsäcker from 1933 to 1936, and second by Niels Bohr and Fritz Kalckar in 1936 and 1937, both of which merged in the minds of Lise Meitner and Otto Robert Frisch at the end of 1938 to yield the correct interpretation of nuclear fission, an act of creation whose understanding rested on a detailed analysis of the published literature.

  12. [The substance of genetic information--nucleic acids].

    PubMed

    Brdička, R

    2012-01-01

    If we look at the history of our knowledge of nucleic acids, we would see in the distant past of 140 years Friedrich Miescher who had identified the acidic substance within the cell nucleus, which he called nuclein. About 70 years after his initial observation, this substance was connected with genetic information. This very substantial finding happened during the World War II. This was the impulse that research of nucleic acids received to speed up continuously growing mountain of information, which is more and more difficult to understand. Another eruption of new information about our genome was the result of ten years of intensive cooperation of many manufacturers divided into two competitive blocks which offered us knowledge of nucleotide sequence of all 46 DNA molecules. The year 2000 became the landmark marking the start of the postgenomic era. It did not mean that human genome was totally explored, but the cornerstone has been settled. Since then, we could concentrate our efforts on variability; use of the project of 1,000 genomes brought many important findings, eg. copy number variability (CNV) exceeds the single nucleotide polymophisms (SNP). Also intergenomic relationships, studies on function and pathways began to be much more understandable by elucidation of the genome primary structure. NGS as a tool also accelerated the epigenetic research. All this improved molecular diagnostics by discovering many new markers playing their role in disease and treatment and allowed us to enter the field of multifactorial illnesses including cancer. The progress in diagnostic technologies which has happened during the last decade forced our research teams to include other professions - eg. bioinformatics.

  13. Pain and Poppies: The Good, the Bad, and the Ugly of Opioid Analgesics

    PubMed Central

    Al-Hasani, Ream; Salvemini, Daniela; Salter, Michael W.; Gutstein, Howard

    2015-01-01

    Treating pain is one of the most difficult challenges in medicine and a key facet of disease management. The isolation of morphine by Friedrich Sertürner in 1804 added an essential pharmacological tool in the treatment of pain and spawned the discovery of a new class of drugs known collectively as opioid analgesics. Revered for their potent pain-relieving effects, even Morpheus the god of dreams could not have dreamt that his opium tincture would be both a gift and a burden to humankind. To date, morphine and other opioids remain essential analgesics for alleviating pain. However, their use is plagued by major side effects, such as analgesic tolerance (diminished pain-relieving effects), hyperalgesia (increased pain sensitivity), and drug dependence. This review highlights recent advances in understanding the key causes of these adverse effects and explores the effect of chronic pain on opioid reward. SIGNIFICANCE STATEMENT Chronic pain is pervasive and afflicts >100 million Americans. Treating pain in these individuals is notoriously difficult and often requires opioids, one of the most powerful and effective classes of drugs used for controlling pain. However, their use is plagued by major side effects, such as a loss of pain-relieving effects (analgesic tolerance), paradoxical pain (hyperalgesia), and addiction. Despite the potential side effects, opioids remain the pharmacological cornerstone of modern pain therapy. This review highlights recent breakthroughs in understanding the key causes of these adverse effects and explores the cellular control of opioid systems in reward and aversion. The findings will challenge traditional views of the good, the bad, and the ugly of opioids. PMID:26468188

  14. ["Fiction and Truth": Goethe's anatomical research at the University of Jena].

    PubMed

    Schäfer, H H; Sivukhina, E; Dölz, W; Oehring, H

    2012-12-01

    Johann Wolfgang von Goethe was one of the most renowned German poets of the late Age of Enlightenment. However, his engagement went far beyond literature especially relating to politics and natural science. Goethe, primarily trained as a lawyer, developed his own theory of colors and even challenged the concepts of Isaac Newton. His discovery of the human intermaxilary bone questioned all the dogmas of the religious-minded world of the 18th century. Together with the anatomy professor Justus Christian Loder, Goethe performed comparative anatomy and proved the conceptual uniformity of humans and animals on 27 March 1784. Even though, Félix Vicq d'Azyr described the intermaxilary bone simultaneously in Catholic France, Goethe's findings were politically accepted due to the liberal Protestantism of the Duchy of Weimar. Nevertheless, leading anatomists of the century (Johann Friedrich Blumenbach, Petrus Camper and Samuel Thomas v. Soemmerring) mainly rejected Goethe's postulates which led to a delayed publication in 1820; almost 36 years after writing his original manuscript. Today, Goethe's discovery is known to be a fundamental basis for the development of Charles Darwin's theory of phylogenetic evolution. Nowadays, the Department of Anatomy contains the Museum Anatomicum Jenense which was founded by the Duke of Weimar, Carl August and Goethe and entails Goethe's premaxillary bones as its main attraction. The University values the cultural heritage of Goethe's contribution to Medicine and provides access to the collection to the public and generations of medical students. Still today Goethe's legacy is noticeable in the halls of the Alma Mater Jenensis. PMID:23233304

  15. The role of the surgeon in the evolution of flexible endoscopy.

    PubMed

    Morgenthal, C B; Richards, W O; Dunkin, B J; Forde, K A; Vitale, G; Lin, E

    2007-06-01

    Several cultures, including the Egyptians, Greeks, Romans, and Arabs, made attempts to view accessible human body cavities using a variety of instruments such as spatulas and specula. The first endoscope was created in 1806 when Phillip Bozzini, a German-born urologist, constructed the lichtleiter, which used concave mirrors to reflect candlelight through an open tube into the esophagus, bladder, or rectum. Maximilian Carl-Friedrich Nitze, another German urologist, produced the first usable cystoscope in 1877 by using series of lenses to increase magnification. He was also the first to place light inside the organ of interest to aid visualization. In 1880 Mikulicz made the first gastroscope using a system similar to Nitze's cystoscope. Modern endoscopy was born with the introduction of the fiberoptic endoscope in the late 1950s. Over the ensuing 50 years endoscopy revolutionized many aspects of the surgeon's practice. Endoscopy can now be used to diagnose and often treat gastrointestinal cancer, hemorrhage, obstruction, and inflammatory conditions. This review was initiated by the SAGES Flexible Endoscopy Committee to chronicle the role of the surgeon in the development and introduction of flexible endoscopy into clinical practice, historically and in contemporary surgery. Flexible endoscopy evolved out of surgeons' need to overcome diagnostic and therapeutic challenges. There have been many recent technological advances that facilitate endoluminal therapies, and flexible endoscopy is now traversing new ground. Surgeons have been major contributors in the development of all aspects of endoscopy. There is a continually expanding list of therapeutic options available to patients. The difficult questions of which procedure, on which patient, and when can be answered best by the surgeon versed in endoscopic, laparoscopic, and open surgical techniques. PMID:17180263

  16. Stability of an overland flow scheme in the framework of a fully coupled eco-hydrological model based on the Macroscopic Cellular Automata approach

    NASA Astrophysics Data System (ADS)

    Mendicino, Giuseppe; Pedace, Jessica; Senatore, Alfonso

    2015-04-01

    Cellular Automata are often used for modeling the evolution in time of environmental systems mainly because they are directly compatible with parallel programming. Nevertheless, defining the optimal time step criterion for integrating forward in time numerical processes can further enhance model computational efficiency. To this aim, a numerical stability analysis of an original overland flow model, within the framework of a fully coupled eco-hydrological system based on the Macroscopic Cellular Automata paradigm, is performed. According to the other modules of the system describing soil water flow, soil-surface-atmosphere fluxes and vegetation dynamics, overland flow model equations were derived through a direct discrete formulation (i.e. no differential equations were discretized), adopting the diffusion wave model as an approximation of the full De Saint Venant equations and including the capability of accounting for specific processes, such as the increasing roughness effects due to vegetation growth or surface-soil water exchanges. Suitable formulations of robust tools usually applied in the stability analyses, such as Courant-Friedrichs-Lewy and von Neumann conditions, were initially derived for the CA-based overland flow model. Afterwards, the theoretical stability conditions were compared to experimental time step constraints through several numerical simulations of a 5-h rain event. Specifically, adopting a constant (i.e. not adaptive) time step for simulations, and discretizing head losses in a way that increases model stability, experimental upper limits preventing numerical instability were found for 13 test cases with different slopes, precipitation intensities, vegetation densities and depths of surface depressions. Even though von Neumann condition and experimental values were well positively correlated, the latter were almost always sensibly lower, excluding cases when free surface gradients tended to zero. Therefore, based on the original method

  17. Ocean surface waves in an ice-free Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Li, Jian-Guo

    2016-08-01

    The retreat of the Arctic ice edge implies that global ocean surface wave models have to be extended at high latitudes or even to cover the North Pole in the future. The obstacles for conventional latitude-longitude grid wave models to cover the whole Arctic are the polar problems associated with their Eulerian advection schemes, including the Courant-Friedrichs-Lewy (CFL) restriction on diminishing grid length towards the Pole, the singularity at the Pole and the invalid scalar assumption for vector components defined relative to the local east direction. A spherical multiple-cell (SMC) grid is designed to solve these problems. It relaxes the CFL restriction by merging the longitudinal cells towards the Poles. A round polar cell is used to remove the singularity of the differential equation at the Pole. A fixed reference direction is introduced to define vector components within a limited Arctic part in mitigation of the scalar assumption errors at high latitudes. The SMC grid has been implemented in the WAVEWATCH III model and validated with altimeter and buoy observations, except for the Arctic part, which could not be fully tested due to a lack of observations as the polar region is still covered by sea ice. Here, an idealised ice-free Arctic case is used to test the Arctic part and it is compared with a reference case with real ice coverage. The comparison indicates that swell wave energy will increase near the ice-free Arctic coastlines due to increased fetch. An expanded Arctic part is used for comparisons of the Arctic part with available satellite measurements. It also provides a direct model comparison between the two reference systems in their overlapping zone.

  18. Evaluating the performance of the particle finite element method in parallel architectures

    NASA Astrophysics Data System (ADS)

    Gimenez, Juan M.; Nigro, Norberto M.; Idelsohn, Sergio R.

    2014-05-01

    This paper presents a high performance implementation for the particle-mesh based method called particle finite element method two (PFEM-2). It consists of a material derivative based formulation of the equations with a hybrid spatial discretization which uses an Eulerian mesh and Lagrangian particles. The main aim of PFEM-2 is to solve transport equations as fast as possible keeping some level of accuracy. The method was found to be competitive with classical Eulerian alternatives for these targets, even in their range of optimal application. To evaluate the goodness of the method with large simulations, it is imperative to use of parallel environments. Parallel strategies for Finite Element Method have been widely studied and many libraries can be used to solve Eulerian stages of PFEM-2. However, Lagrangian stages, such as streamline integration, must be developed considering the parallel strategy selected. The main drawback of PFEM-2 is the large amount of memory needed, which limits its application to large problems with only one computer. Therefore, a distributed-memory implementation is urgently needed. Unlike a shared-memory approach, using domain decomposition the memory is automatically isolated, thus avoiding race conditions; however new issues appear due to data distribution over the processes. Thus, a domain decomposition strategy for both particle and mesh is adopted, which minimizes the communication between processes. Finally, performance analysis running over multicore and multinode architectures are presented. The Courant-Friedrichs-Lewy number used influences the efficiency of the parallelization and, in some cases, a weighted partitioning can be used to improve the speed-up. However the total cputime for cases presented is lower than that obtained when using classical Eulerian strategies.

  19. Science as theater, theater as science

    NASA Astrophysics Data System (ADS)

    Lustig, Harry

    2002-04-01

    Beginning with Bertold Brecht's "Galileo" in 1942 and Friedrich Dürrenmatt's "The Physicists" in 1962, physics and other sciences have served a number of dramatists as backdrops for the exposition of existential problems, as well as the provision of entertainment. Michael Frayn's 1998 play "Copenhagen" broke new ground by giving a central role to the presentation of scientific substance and ideas and to the examination of recent controversial and emotionally charged events in the history of science and of the "real world". A rash of "science plays" erupted. How should we physicists react to this development? Surely, it can be argued, any exposure of science to the public is better than none and will help break down the barriers between the "two cultures". But what if the science or the scientists are badly misrepresented or the play is a weapon to strip science of its legitimacy and its claims to reality and truth? After reviewing a half dozen of the new plays, I conclude that "Copenhagen", though flawed, is not only the best of show, but a positive, even admirable endeavor. The contributions of Bohr, Heisenberg, Born, Schrödinger, and other scientists and their interactions in the golden years of the creation of quantum mechanics are accurately and thrillingly rendered. There may be no better non-technical exposition of complementarity and the uncertainty principle than the one that Frayn puts into the mouths of Bohr and Heisenberg. The treatment of the history of the atomic bomb and Heisenberg's role in Germany's failure to achieve a bomb is another matter. Frayn can also be criticized for applying uncertainly and complementarity to the macroscopic world and, in particular, to human interactions, thereby giving some aid and comfort to the post-modernists. These reservations aside, Copenhagen is a beautiful contribution to the appreciation of science.

  20. A unified radiative magnetohydrodynamics code for lightning-like discharge simulations

    SciTech Connect

    Chen, Qiang Chen, Bin Xiong, Run; Cai, Zhaoyang; Chen, P. F.

    2014-03-15

    A two-dimensional Eulerian finite difference code is developed for solving the non-ideal magnetohydrodynamic (MHD) equations including the effects of self-consistent magnetic field, thermal conduction, resistivity, gravity, and radiation transfer, which when combined with specified pulse current models and plasma equations of state, can be used as a unified lightning return stroke solver. The differential equations are written in the covariant form in the cylindrical geometry and kept in the conservative form which enables some high-accuracy shock capturing schemes to be equipped in the lightning channel configuration naturally. In this code, the 5-order weighted essentially non-oscillatory scheme combined with Lax-Friedrichs flux splitting method is introduced for computing the convection terms of the MHD equations. The 3-order total variation diminishing Runge-Kutta integral operator is also equipped to keep the time-space accuracy of consistency. The numerical algorithms for non-ideal terms, e.g., artificial viscosity, resistivity, and thermal conduction, are introduced in the code via operator splitting method. This code assumes the radiation is in local thermodynamic equilibrium with plasma components and the flux limited diffusion algorithm with grey opacities is implemented for computing the radiation transfer. The transport coefficients and equation of state in this code are obtained from detailed particle population distribution calculation, which makes the numerical model is self-consistent. This code is systematically validated via the Sedov blast solutions and then used for lightning return stroke simulations with the peak current being 20 kA, 30 kA, and 40 kA, respectively. The results show that this numerical model consistent with observations and previous numerical results. The population distribution evolution and energy conservation problems are also discussed.