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Sample records for alexander von humbolt

  1. [Researchers training in the context of the collaborative projects: experiences of Instituto de Medicina Tropical "Alexander von Humbolt", Universidad Peruana Cayetano Heredia].

    PubMed

    Gotuzzo, Eduardo; González, Elsa; Verdonck, Kristien

    2010-09-01

    Research is a main element for human and social development. Under this point of view, it involves particular challenges and opportunities for the so-called "developing countries". An approach for those challenges and opportunities comes from the analysis of two interrelated activities; the training of new researchers and the research development with institutions or researchers which are external to the institution ("collaborative research"). Both activities are essential for the consolidation, widening and updating of the institutional capabilities for scientific production. We present here the experiences of the Instituto de Medicina Tropical "Alexander von Humboldt" of the Universidad Peruana Cayetano Heredia, in relation to the training of new researchers, we discuss the four elements we consider key for this process; the promotion of stimulating environments for research, the proactive identification of fellows, the complementary advice and networks consolidation; and we analyze three successful models of international collaboration for the training of new researchers under different institutional approaches.

  2. Alexander von Humboldt's perceptions of colonial Spanish America.

    PubMed

    Rebok, Sandra

    2009-01-01

    This study presents an in-depth analysis of Alexander von Humboldt's descriptions and critical comments on the colonial society of the different regions he visited during his well-known expedition through the Americas (1799-1804). The criticisms of colonialism that he expressed, reflecting his personal convictions, have already been the focal point of many studies, but Humboldt also was able to offer a more differentiated assessment through comparisons of regional and local traditions and developments. This essay focuses on his personal diaries, which offer many interesting comments on colonial societies. These considerations and impressions made during the expedition are of particular scholarly value since they were not subject to censorship of any kind.

  3. [Urology and National Socialism: the fate of Alexander von Lichtenberg 1880-1949].

    PubMed

    Moll, F H; Krischel, M; Rathert, P; Fangerau, H

    2010-09-01

    Alexander von Lichtenberg (1880-1949) was one of the famous members of the German Urological Society (DGU) in pre-war Germany. He introduced excretion urography and a special TURP Instrument. In 1928 he was president of the 8th meeting held in the German capital Berlin. His Handbook of Urology, released by Ferdinand Springer publishing house, was a trendsetter in establishing urology as a specialty in Germany and bringing together the whole wisdom of all aspects of urology. He was the founder of the famous Maximilian Nitze Award of the DGU. As a Jew he-like many others-was forced to leave Nazi Germany after 1933. Even in Hungary, his native country, he again had to resist anti-Semitic hostility. Later on he lived in Mexico. Alexander von Lichtenberg has to be remembered with special focus on the exodus of German Jewish scientists during the Nazi time.

  4. Alexander von Humboldt: galvanism, animal electricity, and self-experimentation part 1: formative years, naturphilosophie, and galvanism.

    PubMed

    Finger, Stanley; Piccolino, Marco; Stahnisch, Frank W

    2013-01-01

    During the 1790s, Alexander von Humboldt (1769-1859), who showed an early interest in many facets of natural philosophy and natural history, delved into the controversial subject of galvanism and animal electricity, hoping to shed light on the basic nature of the nerve force. He was motivated by his broad worldview, the experiments of Luigi Galvani, who favored animal electricity in more than a few specialized fishes, and the thinking of Alessandro Volta, who accepted specialized fish electricity but was not willing to generalize to other animals, thinking Galvani's frog experiments flawed by his use of metals. Differing from many German Naturphilosophen, who shunned "violent" experiments, the newest instruments, and detailed measurement, Humboldt conducted thousands of galvanic experiments on animals and animal parts, as well as many on his own body, some of which caused him great pain. He interpreted his results as supporting some but not all of the claims made by both Galvani and Volta. Notably, because of certain negative findings and phenomenological differences, he remained skeptical about the intrinsic animal force being qualitatively identical to true electricity. Hence, he referred to a "galvanic force," not animal electricity, in his letters and publications, a theoretical position he would abandon with Volta's help early in the new century.

  5. Measuring the World: How theory follows observation (Alexander von Humboldt Medal)

    NASA Astrophysics Data System (ADS)

    Savenije, Hubert H. G.

    2015-04-01

    I started my professional career as a hydrologist working for the government of Mozambique. I was responsible for overseeing the hydrological network, the operational hydrology and answering specific questions related to water resources availability and the occurrence of floods. In the late 1970s and early 1980s, the use of telecommunication and computers was still very limited. We had to work with handbooks, lecture notes and consultancy reports, but mostly with our brains. The key to answering a specific question was to go into the field and observe. We measured as much as we could to understand the processes that we observed. I didn't know it at the time, but this perfectly fits in the tradition of Von Humboldt. During my time in Mozambique I surveyed during and after extreme floods, such as the 1984 flood caused by the tropical cyclone Demoina. I surveyed the geometry, hydraulics and salt intrusion of 4 major Mozambican estuaries. And I measured the quality and the quantity of the flows draining onto these estuaries. Having only limited access to the literature, it was a survey without much theoretical guidance. This maybe slowed us down a bit, and sometimes led to inefficient approaches, but scientifically it was a gold mine. Not being biased by established theories is a great advantage. One does not follow onto the well-trodden, but sometimes erroneous, paths of others. After working for 6 years in Mozambique I joined an international consultant, for whom I worked for 6 years in many different countries in Asia, Africa and South America. Although the access to literature and other people's experience was better, I continued the practice of observing before believing. These 12 years of doing hydrology in practice formed the basis for the development of my own theories on hydrological processes, salt intrusion in estuaries, tidal hydraulics and even atmospheric moisture recycling. So when I started on my PhD at the age of 38, I made a completely different start

  6. Alexander von Humboldt: galvanism, animal electricity, and self-experimentation part 2: the electric eel, animal electricity, and later years.

    PubMed

    Finger, Stanley; Piccolino, Marco; Stahnisch, Frank W

    2013-01-01

    After extensive experimentation during the 1790s, Alexander von Humboldt remained skeptical about "animal electricity" (and metallic electricity), writing instead about an ill-defined galvanic force. With his worldview and wishing to learn more, he studied electric eels in South America just as the new century began, again using his body as a scientific instrument in many of his experiments. As had been the case in the past and for many of the same reasons, some of his findings with the electric eel (and soon after, Italian torpedoes) seemed to argue against biological electricity. But he no longer used galvanic terminology when describing his electric fish experiments. The fact that he now wrote about animal electricity rather than a different "galvanic" force owed much to Alessandro Volta, who had come forth with his "pile" (battery) for multipling the physical and perceptable effects of otherwise weak electricity in 1800, while Humboldt was deep in South America. Humboldt probably read about and saw voltaic batteries in the United States in 1804, but the time he spent with Volta in 1805 was probably more significant in his conversion from a galvanic to an electrical framework for understanding nerve and muscle physiology. Although he did not continue his animal electricity research program after this time, Humboldt retained his worldview of a unified nature and continued to believe in intrinsic animal electricity. He also served as a patron to some of the most important figures in the new field of electrophysiology (e.g., Hermann Helmholtz and Emil du Bois-Reymond), helping to take the research that he had participated in to the next level.

  7. Geosciences Information for Teachers (GIFT) Workshops held in Conjunction with Alexander von Humboldt (AvH) EGU Conferences

    NASA Astrophysics Data System (ADS)

    Laj, Carlo; Cifelli, Francesca

    2015-04-01

    The Alexander von Humboldt Conference Series of the European Geosciences Union are a series of meetings held outside of Europe, in particular in South America, Africa or Asia, on selected topics of geosciences with a socio-economic impact for regions on these continents, jointly organised with the scientists and their institutes and the institutions of these regions. Given the increasing success of the GIFT workshops held in conjunction with the General Assemblies, since 2010 EGU has also developed a series of GIFT workshops held in conjunction with AvH conferences. Associated GIFT workshops were held in Merida, Yucatan, on the theme of Climate Change, Natural Hazards and Societies (March 2010), then in Penang, Malaysia (June 2011) on the theme of Ocean Acidification, in November 2012 in Cusco (Peru) on the theme of Natural Disasters, Global Change and the Preservation of World Heritage Sites, finally in Istanbul (March 2014) on "High Impact Natural Hazards Related to the Euro-Mediterranean Region. The next GIFT workshop is already planned for October 2015 in Adis Ababa (Ethiopia) on the theme "Water". In each case, the GIFT workshop was held on the last two days of the AvH conference and reunited 40-45 teachers from the nation where the AvH was held. Keynote speakers from AvH were speakers to the GIFT workshops which also included hands-on activities animated by sciences educators. These GIFT workshops represented the first workshops specifically aimed at teachers held in the country, and therefore represents a significant Earth Sciences contribution to secondary education in non European countries.

  8. Geosciences Information for Teachers (GIFT) Workshops held in Conjunction with Alexander von Humboldt (AvH) EGU Conferences.

    NASA Astrophysics Data System (ADS)

    Laj, C. E.; Cifelli, F.

    2014-12-01

    Given the increasing success of the GIFT workshops held in conjunction with the General Assemblies, since 2010 EGU has also developed a series of GIFT workshops held in conjunction with AvH conferences. The Alexander von Humboldt Conference Series of the European Geosciences Union are a series of meetings held outside of Europe, in particular in South America, Africa or Asia, on selected topics of geosciences with a socio-economic impact for regions on these continents, jointly organised with the scientists and their institutes and the institutions of these regions. Associated GIFT workshops were held in Merida, Yucatan, on the theme of Climate Change, Natural Hazards and Societies (March 2010), then in Penang, Malaysia (June 2011) on the theme of Ocean Acidification, in November 2012 in Cusco (Peru) on the theme of Natural Disasters, Global Change and the Preservation of World Heritage Sites, finally in Istanbul (March 2014) on "High Impact Natural Hazards Related to the Euro-Mediterranean Region. The next GIFT workshop is already planned for October 2015 in Adis Ababa (Ethiopia) on the theme "Water". In each case, the GIFT workshop was held on the last two days of the AvH conference and reunited 40-45 teachers from the nation where the AvH was held. Keynote speakers from AvH were speakers to the GIFT workshops which also included hands-on activities animated by sciences educators. In 3 cases of the 4 cases, these GIFT workshops represented the first workshop specifically aimed at teachers held in the country, and therefore represents a significant Earth Sciences contribution to secondary education in non European countries.

  9. Alexander Disease

    MedlinePlus

    ... mice have been engineered to produce the same mutant forms of GFAP found in individuals with Alexander ... mice have been engineered to produce the same mutant forms of GFAP found in individuals with Alexander ...

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

    ERIC Educational Resources Information Center

    Thomas, Carla R.

    1973-01-01

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

  11. Remembering Alexander Meiklejohn.

    ERIC Educational Resources Information Center

    Tussman, Joseph

    1984-01-01

    A former student of Alexander Meiklejohn, a member of the Experimental College movement on the 1930s, describes his impressions of Meiklejohn's life, leadership qualities, and personal characteristics. (MSE)

  12. Humboldt, Alexander von (1769-1859)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Naturalist, geographer, explorer, born in Tegel Palace, Berlin. The Humboldt current off the west coast of South America is named after him. He named the gegenschein. He set in train an international project organized by GAUSS to study terrestrial magnetism. His major work, Kosmos, based on lectures at Berlin University, endeavoured to provide a comprehensive physical picture of the universe. ...

  13. Alexander I. Ignatowski

    PubMed Central

    Konstantinov, Igor E.; Jankovic, Gradimir M.

    2013-01-01

    In 1908, Alexander I. Ignatowski (1875–1955) published his pioneering work that first revealed a relationship between cholesterol-rich food and experimental atherosclerosis. This early experimental work paved a way to the metabolic study of the mechanism of atherosclerosis. Herein, we present a brief account of Ignatowski's work and life. PMID:23914012

  14. Illustrated and online catalog of type specimens of freshwater fishes in the Colección de Peces Dulceacuícolas of Instituto de Investigación de Recursos Biológicos Alexander von Humboldt (IAvH-P), Colombia.

    PubMed

    Donascimiento, Carlos; Cárdenas-Bautista, Johann-Stephens; Acosta, Kevin Giancarlo Borja; González-Alvarado, Arturo; Medina, Claudia A

    2016-09-29

    The catalog of type specimens of freshwater fishes deposited in the Colección de Peces Dulceacuícolas del Instituto de Investigación de Recursos Biológicos Alexander von Humboldt (IAvH-P) is presented. This list includes 483 specimens in 65 lots representing 11 holotypes and 472 paratypes of 48 nominal species. Corrections, additions, and updating of information in the original descriptions are included in individual remarks for each catalog number entry and a gallery of pictures of holotypes or paratypes of each nominal species is also presented, which supplements some original descriptions lacking figures of their respective types. An online version of the catalog is available at http://humboldt.org.co/en/servicios/colecciones-biologicas/catalogo-de-tipos.

  15. Alexander's Law revisited.

    PubMed

    Jeffcoat, Benjamin; Shelukhin, Alexander; Fong, Alex; Mustain, William; Zhou, Wu

    2008-07-01

    Alexander's Law states that the slow-phase velocity of the nystagmus caused by unilateral vestibular lesion increases with gaze in the beat direction. Two studies have shown that this gaze effect is generalized to the nystagmus caused by unilateral cold water irrigation. This indicates that the gaze effect is not the result of central changes associated with a peripheral lesion but rather because of unilateral vestibular peripheral inhibition. In this study, we show that there is a similar gaze effect on the nystagmus produced by unilateral warm water ear irrigation. Furthermore, we examined the two hypotheses of Alexander's Law proposed in the two studies. One hypothesis is based on the gaze-dependent modulation of the vestibulo-ocular reflex (VOR) response to unbalanced canal input. The other hypothesis, however, is based on the leaky neural integrator caused by unilateral vestibular peripheral inhibition. These two hypotheses predict the same gaze effect on the nystagmus produced by cold water irrigation, but opposite gaze effects on the nystagmus produced by warm water irrigation. Our results support the first hypothesis and suggest that the second hypothesis needs to be modified.

  16. Alexander Archipelago, Southeastern Alaska

    NASA Technical Reports Server (NTRS)

    2002-01-01

    West of British Columbia, Canada, and south of the Yukon Territory, the southeastern coastline of Alaska trails off into the islands of the Alexander Archipelago. The area is rugged and contains many long, U-shaped, glaciated valleys, many of which terminate at tidewater. The Alexander Archipelago is home to Glacier Bay National Park. The large bay that has two forks on its northern end is Glacier Bay itself. The eastern fork is Muir inlet, into which runs the Muir glacier, named for the famous Scottish-born naturalist John Muir. Glacier Bay opens up into the Icy Strait. The large, solid white area to the west is Brady Icefield, which terminates at the southern end in Brady's Glacier. To locate more interesting features from Glacier Bay National Park, take a look at the park service map. As recently as two hundred years ago, a massive ice field extended into Icy Strait and filled the Glacier Bay. Since that time, the area has experienced rapid deglaciation, with many large glaciers retreating 40, 60, even 80 km. While temperatures have increased in the region, it is still unclear whether the rapid recession is part of the natural cycle of tidewater glaciers or is an indicator of longer-term climate change. For more on Glacier Bay and climate change, read an online paper by Dr. Dorothy Hall, a MODIS Associate Science Team Member. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  17. Genetics Home Reference: Alexander disease

    MedlinePlus

    ... up study of 22 Chinese children with Alexander disease and analysis of parental origin of de novo GFAP mutations. J Hum Genet. 2013 Apr;58(4):183-8. doi: 10.1038/jhg.2012.152. Epub 2013 Jan 31. Citation on ... GS. Alexander disease: ventricular garlands and abnormalities of the medulla and ...

  18. [Improvement of hygiene and the combat of epidemics as Russian state concerns during World War I: Prince Alexander von Oldenburg and the POWs of the Central Powers in Russia].

    PubMed

    Nachtigal, Reinhard

    2004-01-01

    When Russia joined the war against the Central Powers in 1914, she immediately faced problems of public health care among the masses of people who were forced to move across far distances in the country: soldiers, refugees, and prisoners of war. Because of poor organisation and the unexpectedly long duration of the war, the POWs fared worst of all war victims in Russia. Subjected to an overstrained military organisation in the rear, the fate of this broadly neglected group illustrates how and with what success Russia strove to meet its deficiencies in administrative structure during wartime. The "Evacuation and Sanitation Section" was put under the command of a member of the Imperial family, Prince Alexander of Oldenburg, a high ranking official of German origin. This amateur scientist and initiator of medical institutions was an energetic and courageous personality who became vital for the fate of millions of POWs in epidemic-stricken Russia. The role of this "silent" ally of the German and Austro-Hungarian governments has hitherto been unknown. Newly found sources in Russian archives now shed an interesting light on a weak spot of Russia's administration and a generally neglected chapter of the history of medicine, the handling of epidemics and of deficits in hygiene.

  19. Robert Alexander and His Passionate Philosophy (Profile).

    ERIC Educational Resources Information Center

    Bosseau, Remi Barclay

    1994-01-01

    Discusses the passionate philosophy of Robert Alexander, founder and director of living stage theater company and his views of art, creativity, the entire process of learning, politics, philosophy, and hope. Presents several excerpts from Alexander's presentations for artists and teachers during Living Stage residencies in cities around the…

  20. Dancers' Application of the Alexander Technique

    ERIC Educational Resources Information Center

    Fortin, Sylvie; Girard, Fernande

    2005-01-01

    This qualitative study describes the experience of professional contemporary dancers studying and applying the Alexander Technique to their dancing. This study was motivated by: 1. years of teaching both dance and somatics, 2. a strong desire to better understand how the Alexander Technique can be applied by dancers, and 3. a gap that the…

  1. The Alexander Technique: An Acting Approach.

    ERIC Educational Resources Information Center

    Barker, Sarah A.

    2002-01-01

    Notes the discrepancy between students' use of the Alexander Technique in class and on stage. Discusses three fundamental self-use objectives of the Alexander Technique: the reduction of excess physical compression and muscularity; the unification of body/voice and thought; and the expansion of the field of attention. Demonstrates how each…

  2. An unusual presentation of juvenile Alexander disease.

    PubMed

    Osorio, Maria Joana; Risen, Sarah; Alper, Gulay

    2012-04-01

    Alexander disease is a rare leukodystrophy that most often presents in infancy but also includes neonatal, juvenile, and adult variants. Juvenile Alexander disease presents primarily with bulbar symptoms between 2 and 12 years of age. The diagnosis is often suggested by the clinical course and brain magnetic resonance image pattern and then confirmed by the presence of a mutation in the glial fibrillary acidic protein gene. A young girl presented with globus sensation and magnetic resonance imaging of the brain revealed abnormalities mainly involving white matter tracts of the medulla oblongata and cerebellum. The presence of a mutation in the glial fibrillary acidic protein gene confirmed the diagnosis of juvenile Alexander disease. A high index of clinical suspicion is necessary for the diagnosis of late-onset presentations of Alexander disease.

  3. The Haunting Influence of Alexander Graham Bell

    ERIC Educational Resources Information Center

    Mitchell, Sue H.

    1971-01-01

    The article examines the significance that Alexander Graham Bell's attitude and actions had on the social and economic conditions experienced by deaf people during his lifetime and into the present. (CD)

  4. [On Alexander's pneumothorax: A critical appraisal].

    PubMed

    Delgado-García, Guillermo; Villarreal-Alarcón, Miguel Ángel; Estañol-Vidal, Bruno

    According to the testimony of Ptolemy, which we know through Arrian, it has been assumed that Alexander the Great suffered a pneumothorax during his campaign against the Malli. In general, this assumption has been interpreted as a historical fact in medical literature. We consulted the same sources and concluded that it is unlikely that Alexander's arrow wound had given him a pneumothorax. In addition, we stressed the extra-historical content of classical sources.

  5. von Karman Vortices

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Each of these swirling clouds is the result of a meteorological phenomenon known as a von Karman vortex. These vortices appeared over Alexander Selkirk Island in the southern Pacific Ocean. Rising precipitously from the surrounding waters, the island's highest point is nearly a mile (1.6 km) above sea level. As wind-driven clouds encounter this obstacle, they flow around it to form large, spinning eddies. This image was acquired by Landsat 7's Enhanced Thematic Mapper plus (ETM+) sensor on September 15, 1999. This is a false-color composite image made using shortwave infrared, infrared, and near-infrared wavelengths. Image provided by the USGS EROS Data Center Satellite Systems Branch.

  6. Alexander Graham Bell: Teacher of the Deaf.

    ERIC Educational Resources Information Center

    Bruce, Robert V.

    The lecture on Alexander Graham Bell by Dr. Robert V. Bruce, the author of a biography of Bell, focuses on Bell's association with the Clarke School for the Deaf in Massachusetts. Noted are Bell's employment by the school at 25 years of age and the preceding period during which Bell taught elocution at a boys' school in Scotland and used his…

  7. The Remarkable Journey of Lloyd Alexander

    ERIC Educational Resources Information Center

    Tunnel, Michael O.; Jacobs, James S.

    2007-01-01

    This article features Lloyd Alexander, an author who has produced some of the most elegant and powerful prose in the history of modern children's literature. Lloyd began writing seriously in high school, and though he wrote and submitted many poems and short stories, his only success was being named a finalist in the "Writer's Digest" Short Story…

  8. Alexander Böhm (1971-2012).

    PubMed

    Boos, Winfried; Parkinson, John S; Jenal, Urs; Vogel, Jörg; Søgaard-Andersen, Lotte

    2013-04-01

    On November 28, 2012 Alexander (Alex) Böhm, a bacterial geneticist, died at age 41, only a few months after taking up a position as an assistant professor at the LOEWE Center for Synthetic Microbiology in Marburg, Germany. Earlier in 2012 Alex had been diagnosed with an aggressive form of thyroid cancer that left him little time to live his scientific and personal dreams.

  9. Dr Elizabeth Alexander: First Female Radio Astronomer

    NASA Astrophysics Data System (ADS)

    Orchiston, Wayne

    2005-01-01

    During March-April 1945, solar radio emission was detected at 200 MHz by operators of a Royal New Zealand Air Force radar unit located on Norfolk Island. Initially dubbed the `Norfolk Island Effect', this anomalous radiation was investigated throughout 1945 by British-born Elizabeth Alexander, head of the Operational Research Section of the Radio Development Laboratory in New Zealand. Alexander prepared a number of reports on this work, and in early 1946 she published a short paper in the newly-launched journal, Radio & Electronics. A geologist by training, Elizabeth Alexander happened to be in the right place at the right time, and unwittingly became the first woman in the world to work in the field that would later become known as radio astronomy. Her research also led to further solar radio astronomy projects in New Zealand in the immediate post-war year, and in part was responsible for the launch of the radio astronomy program at the Division of Radiophysics, CSIRO, in Sydney.

  10. 1. Historic American Buildings Survey J. Alexander, Photographer, 1971 MASSACHUSETTS ...

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

    1. Historic American Buildings Survey J. Alexander, Photographer, 1971 MASSACHUSETTS AVENUE FACADE, 1971 - James C. Hooe House, 2230 Massachusetts Avenue Northwest, Washington, District of Columbia, DC

  11. 5. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

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

    5. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 DETAIL OF BASEMENT FIREPLACE - Indian Trading Post, Second & Merchant Streets, Sainte Genevieve, Ste. Genevieve County, MO

  12. 4. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

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

    4. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 DETAIL OF STONEWORK (WEST ELEVATION) - Indian Trading Post, Second & Merchant Streets, Sainte Genevieve, Ste. Genevieve County, MO

  13. "Most brilliant in judgment": Alexander the Great and Aristotle.

    PubMed

    Lainas, Panagiotis; Panutsopulos, Dimitrios; Skandalakis, Panagiotis N; Zoras, Odysseas; Skandalakis, John E

    2005-03-01

    From historical sources, it is evident that Alexander the Great was indebted to one of his teachers, Aristotle of Stagira. It was the teaching of Aristotle that evoked all the nascent talents of young Alexander and turned him into a great man. Alexander was extremely interested in the secrets of medicine and considered it an art. The medical knowledge he acquired from Aristotle may have saved his life and the lives of his troops on many occasions. If Alexander did not possess medical knowledge and if his everyday life had not been so greatly influenced by medicine, he might never have been able to create his empire.

  14. 6. Historic American Buildings Survey J. Alexander, Photographer, 1971 VIEW ...

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

    6. Historic American Buildings Survey J. Alexander, Photographer, 1971 VIEW FROM SITTING ROOM INTO DRAWING ROOM - Joseph Beale House, 2301 Massachusetts Avenue, Northwest, Washington, District of Columbia, DC

  15. 3. Historic American Buildings Survey J. Alexander, Photographer, 1971 DETAIL, ...

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

    3. Historic American Buildings Survey J. Alexander, Photographer, 1971 DETAIL, ENTRANCE STOOP (LION FIGURE) - Joseph Beale House, 2301 Massachusetts Avenue, Northwest, Washington, District of Columbia, DC

  16. Heterangaeus Alexander, 1925 crane flies (Diptera: Pediciidae) of Korea.

    PubMed

    Podenas, Sigitas; Podeniene, Virginija; Byun, Hye-Woo

    2015-08-25

    The Korean crane fly species of the genus Heterangaeus Alexander, 1925 (Diptera: Pediciidae) is taxonomically revised. H. gloriosus gloriosus (Alexander, 1924) is redescribed. A new species Heterangaeus koreanus n. sp., which is the first species of Pediciidae from South Korea, is described and illustrated.

  17. Von Humboldt bis Einstein. Berlin als Weltzentrum der exakten Wissenschaften.

    NASA Astrophysics Data System (ADS)

    Meschkowski, H.

    Contents: 1. Die Anfänge. 2. Die Ära Dirichlet-Jacobi. 3. Der Ausbau der experimentellen Naturwissenschaften. 4. Alexander von Humboldt. 5. Berlin wird "Weltzentrum" der Mathematik. 6. Die Ära Helmholtz. 7. Neue Arbeitsweisen der Astronomie. 8. Chemie: Forschung und Industrie. 9. Max Planck. 10. Ins technische Zeitalter. 11. Zur Mathematik der zwanziger Jahre. 12. Albert Einstein. 13. Fortschritte der Grundlagenforschung. 14. Erwin Schrödinger: Physiker, Philosoph und Poet. 15. Zum Schluß.

  18. Recognizing the Presidents: Was Alexander Hamilton President?

    PubMed

    Roediger, Henry L; DeSoto, K Andrew

    2016-05-01

    Studies over the past 40 years have shown that Americans can recall about half the U.S. presidents. Do people know the presidents even though they are unable to access them for recall? We investigated this question using the powerful cues of a recognition test. Specifically, we tested the ability of 326 online subjects to recognize U.S. presidents when presented with their full names among various types of lures. The hit rate for presidential recognition was .88, well above the proportion produced in free recall but far from perfect. Presidents Franklin Pierce and Chester Arthur were recognized less than 60% of the time. Interestingly, four nonpresidents were falsely recognized at relatively high rates, and Alexander Hamilton was more frequently identified as president than were several actual presidents. Even on a recognition test, knowledge of American presidents is imperfect and prone to error. The false alarm data support the theory that false fame can arise from contextual familiarity.

  19. 4. Historic American Buildings Survey J. Alexander, Photographer October 1968 ...

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

    4. Historic American Buildings Survey J. Alexander, Photographer October 1968 FIRST FLOOR NORTH PARLOR, FIREPLACE - Smith-Morton Row House, 3034 P Street Northwest, Washington, District of Columbia, DC

  20. 1. Historic American Buildings Survey J. Alexander, Photographer April 1969 ...

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

    1. Historic American Buildings Survey J. Alexander, Photographer April 1969 3034 P STREET (right) AND ADJOINING ROWHOUSES, LOOKING EAST - Smith-Morton Row House, 3034 P Street Northwest, Washington, District of Columbia, DC

  1. 3. Historic American Buildings Survey J. Alexander, Photographer October 1968 ...

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

    3. Historic American Buildings Survey J. Alexander, Photographer October 1968 VIEW OF SOUTH PARLOR FROM NORTH PARLOR - Smith-Morton Row House, 3034 P Street Northwest, Washington, District of Columbia, DC

  2. 1. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

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

    1. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 VIEW FROM SOUTHEAST - Jean Baptiste Valle House, 99 South Main Street (Northwest corner of Main & Market Streets), Sainte Genevieve, Ste. Genevieve County, MO

  3. 3. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

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

    3. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 VIEW FROM NORTH - Jean Baptiste Valle House, 99 South Main Street (Northwest corner of Main & Market Streets), Sainte Genevieve, Ste. Genevieve County, MO

  4. 2. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

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

    2. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 VIEW FROM SOUTHWEST - Jean Baptiste Valle House, 99 South Main Street (Northwest corner of Main & Market Streets), Sainte Genevieve, Ste. Genevieve County, MO

  5. Alexander F. Chamberlain: a life's work.

    PubMed

    Berkman, Julia M

    2005-01-01

    This article examines the life and work of Alexander Francis Chamberlain. Though he has received little attention since the early 1900s, the importance of this scholar should not be underestimated. Chamberlain made notable contributions to the body of knowledge in anthropology-a discipline that, at the time, was a combination of anthropological and psychological inquiry. His early work began with investigations into the cultures and languages of two Indian tribes indigenous to Canada and the northern United States and, within a few decades, positioned Chamberlain as the leading scholar in this domain. Beyond his ethnographic insights, Chamberlain queried the development of the child and wrote on the subject of childhood in world folklore. He concerned himself with a scope of worthwhile subjects ranging from linguistics to women's suffrage. No topic was out of range as all forms of human study addressed the need for seeing each group as a contributing force to humanity at large. Chamberlain emphasized that no single racial, ethnic, or religious group should be singled out as inherently superior to another, a belief far ahead of his time. This article is an attempt at drawing a picture of a man whose scholarly achievements and strength of character are captured in the depth and breadth of his writing.

  6. 'Mind in general' by Sir Alexander Crichton.

    PubMed

    Berrios, G E

    2006-12-01

    The history of the 'philosophies of psychiatry' can be defined as the contextualized study of past theoretical views on the nature, understanding and management of madness and related notions. The application of an hermeneutic apparatus to past psychiatric narratives gives rise to the history of psychiatry; its application to current narrative gives origin to the philosophy of psychiatry. If the latter employs off-the-shelf, ready-made, external philosophies, it follows a centripetal approach; if it starts from the inside of psychiatry and generates its own tools and meta-language, it follows a centrifugal approach. Psychiatry is burdened by intrinsic and extrinsic philosophical problems. The former result from its hybrid nature, i.e., from the fact that psychiatry unsteadily straddles the natural and human sciences. The latter are borrowed from the conceptual frames into which psychiatry has been inscribed since the 19th century. The philosophy of psychiatry may anticipate or follow empirical research. The ante rem mode is based on the idea that empirical research requires conceptual supervision, audit and guidance, for it is always ideology- and theory-laden. The post rem mode is based on the view that science is the only way to 'truth' and hence all that the philosophy of psychiatry can (or should) do is facilitate, interpret, justify, defend or glorify empirical findings. The Classic Text that follows was written by Sir Alexander Crichton at the end of the 18th century, and is a good example of the centripetal mode of philosophy-making.

  7. von Willebrand Disease

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Von Willebrand Disease? Von Willebrand disease (VWD) is a bleeding disorder. ... while hemophilia mainly affects males. Types of von Willebrand Disease The three major types of VWD are called ...

  8. Astrocytic TDP-43 pathology in Alexander disease.

    PubMed

    Walker, Adam K; Daniels, Christine M LaPash; Goldman, James E; Trojanowski, John Q; Lee, Virginia M-Y; Messing, Albee

    2014-05-07

    Alexander disease (AxD) is a rare neurodegenerative disorder characterized pathologically by the presence of eosinophilic inclusions known as Rosenthal fibers (RFs) within astrocytes, and is caused by dominant mutations in the coding region of the gene encoding glial fibrillary acidic protein (GFAP). GFAP is the major astrocytic intermediate filament, and in AxD patient brain tissue GFAP is a major component of RFs. TAR DNA binding protein of 43 kDa (TDP-43) is the major pathological protein in almost all cases of the neurodegenerative disease amyotrophic lateral sclerosis (ALS) and ∼50% of frontotemporal lobar degeneration (FTLD), designated as FTLD-TDP. In ALS and FTLD-TDP, TDP-43 becomes insoluble, ubiquitinated, and pathologically phosphorylated and accumulates in cytoplasmic inclusions in both neurons and glia of affected brain and spinal cord regions. Previously, TDP-43 was detected in RFs of human pilocytic astrocytomas; however, involvement of TDP-43 in AxD has not been determined. Here we show that TDP-43 is present in RFs in AxD patient brains, and that insoluble phosphorylated full-length and high molecular weight TDP-43 accumulates in white matter of such brains. Phosphorylated TDP-43 also accumulates in the detergent-insoluble fraction from affected brain regions of Gfap(R236H/+) knock-in mice, which harbor a GFAP mutation homologous to one that causes AxD in humans, and TDP-43 colocalizes with astrocytic RF pathology in Gfap(R236H/+) mice and transgenic mice overexpressing human wild-type GFAP. These findings suggest common pathogenic mechanisms in ALS, FTLD, and AxD, and this is the first report of TDP-43 involvement in a neurological disorder primarily affecting astrocytes.

  9. Zanvil Alexander Cohn 1926-1993

    PubMed Central

    1994-01-01

    Zanvil Alexander Cohn, an editor of this Journal since 1973, died suddenly on June 28, 1993. Cohn is best known as the father of the current era of macrophage biology. Many of his scientific accomplishments are recounted here, beginning with seminal studies on the granules of phagocytes that were performed with his close colleague and former editor of this Journal, James Hirsch. Cohn and Hirsch identified the granules as lysosomes that discharged their contents of digestive enzymes into vacuoles containing phagocytosed microbes. These findings were part of the formative era of cell biology and initiated the modern study of endocytosis and cell-mediated resistance to infection. Cohn further explored the endocytic apparatus in pioneering studies of the mouse peritoneal macrophage in culture. He described vesicular inputs from the cell surface and Golgi apparatus and documented the thoroughness of substrate digestion within lysosomal vacuoles that would only permit the egress of monosaccharides and amino acids. These discoveries created a vigorous environment for graduate students, postdoctoral fellows, and junior and visiting faculty. Some of the major findings that emerged from Cohn's collaborations included the radioiodination of the plasma membrane for studies of composition and turnover; membrane recycling during endocytosis; the origin of the mononuclear phagocyte system in situ; the discovery of the dendritic cell system of antigen-presenting cells; the macrophage as a secretory cell, including the release of proteases and large amounts of prostaglandins and leukotrienes; several defined parameters of macrophage activation, especially the ability of T cell-derived lymphokines to enhance killing of tumor cells and intracellular protozoa; the granule discharge mechanism whereby cytotoxic lymphocytes release the pore-forming protein perforin; the signaling of macrophages via myristoylated substrates of protein kinase C; and a tissue culture model in which

  10. 8. View of southwest rear and southeast side of AlexanderAlmon ...

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

    8. View of southwest rear and southeast side of Alexander-Almon House with cement block outbuilding to far left, facing north. - Alexander-Almon House, 130 Philip Almon Road, Roopville, Carroll County, GA

  11. 12. Detail view of southeast side window of AlexanderAlmon House ...

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

    12. Detail view of southeast side window of Alexander-Almon House with rain barrel at lower left and roof rafter tails at top, facing northwest. - Alexander-Almon House, 130 Philip Almon Road, Roopville, Carroll County, GA

  12. Obituary: Walter Alexander Feibelman, 1930-2004

    NASA Astrophysics Data System (ADS)

    Oergerle, William

    2005-12-01

    Walter Alexander Feibelman, 79, an astronomer who discovered the E-ring of Saturn, died of a heart attack 19 November 2004 at his home at Riderwood Village in Silver Spring, Maryland. Walter was born 30 October 1925 in Berlin, Germany to Bernard and Dora Feibelman. He came to the United States with his parents in 1941. They were some of the last German Jews to flee Nazi Germany. Years later, he reported his experiences in an account contributed to the U.S. Holocaust Memorial Museum. As a youth, he worked at a cleaning shop and as a soda jerk before taking a course in tool and die making. He worked at the Abbey Photo Corp. in New York and in a model-making firm, where he constructed models of aircraft for use in identification courses by the Army Air Forces. After high school, he attended the Carnegie Institute of Technology and received his BS degree in 1956. Until 1969, he was a research scientist at the University of Pittsburgh. While working as an assistant research professor in physics and astronomy at the University of Pittsburgh in 1967, he examined a photo of Saturn taken a year earlier at the university's Allegheny Observatory. The E-ring -- unlike the bright main rings, A, B, C, D and F -- is faint and not easily spotted. He paired his observation with calculations and announced his discovery, which remained unconfirmed until the Pioneer 11 flyby in 1979. Walter joined the Optical Astronomy Division of Goddard Space Flight Center in Greenbelt in 1969, and worked there until 2002, when he became an emeritus astronomer at NASA. He became associated with the International Ultraviolet Explorer project, and worked on developing detectors for the orbiting observatory's spectrograph. The project turned out to be one of NASA's most successful observatories, operating from 1978 to 1996. In his scientific career, he published more than 200 refereed articles, mainly on hot stars and planetary nebulae. He also wrote papers in the fields of photography, spectroscopy

  13. Obituary: Donald Alexander Macrae, 1916-2006

    NASA Astrophysics Data System (ADS)

    Seaquist, E. R.

    2007-12-01

    With the passing of Donald Alexander MacRae on 6 December 2006 at age 90, the astronomy community lost a visionary scientist and a great educator in the field. Don MacRae was born in Halifax, Nova Scotia, on 19 February 1916, to Donald Alexander and Laura Geddes (Barnstead) MacRae. His father was originally a classics scholar and preceptor of Greek and Latin at Princeton, but at the time of Don's birth in 1916 he was Dean of the Dalhousie Law School in Halifax. The family moved to Toronto, Ontario, in 1924 when his father joined the faculty of Osgoode Hall Law School in Toronto as a Professor of Law. After the family moved to Toronto, where he received most of his early education, he obtained his undergraduate degree in Mathematics and Physics in 1937 from the University of Toronto (U of T). He obtained the degree of A.M. in 1940 and of Ph.D. in 1943 from Harvard University under the mentorship of Bart Bok in the field of galactic structure. During his early career he worked briefly at the University of Pennsylvania, Cornell University, and Carbide and Chemical Corporation at Oak Ridge, Tennessee. For Don the latter work was a brief and somewhat uneasy association with the Manhattan Project. In 1946, he obtained a position at Case Institute of Technology (now Case Western Reserve University), where he worked until 1953. In 1953, he accepted a position at the U of T, replacing Ralph Williamson, who had earlier introduced Don to the emerging field of radio astronomy while they both were at Cornell. Don's primary research field was stellar spectroscopy, but his interests were much broader than this, and he possessed an abiding ability to interest students and faculty in new and emerging ideas. In the early 1960s he developed a strong interest in the nature and origin of the lunar surface, and discussed these extensively with colleagues. Many of his ideas on this subject were later confirmed by the lunar exploration program. Don's continuing interest in radio astronomy

  14. Teaching Nuclear Radiation and the Poisoning of Alexander Litvinenko

    ERIC Educational Resources Information Center

    David R. Lapp

    2008-01-01

    The recent international story about the death of the former KGB agent Alexander Litvinenko has more than just a few wondering about radiation poisoning and the sinister sounding polonium-210. I was preparing to begin a nuclear radiation unit the Monday after Thanksgiving 2006. As it turned out, Litvinenko died Thanksgiving Day after a short and…

  15. All Aboard the Engine of Reform: Lamar Alexander.

    ERIC Educational Resources Information Center

    Harrington-Lueker, Donna

    1991-01-01

    Transformation of schools is the key to America 2000, an ambitious amalgam of ideas that Secretary of Education Lamar Alexander and his advisers have developed. The program's centerpiece is the creation of 535 "New American Schools" receiving a 1-time $1 million federal grant to develop exemplary programs. A sidebar describes the…

  16. The Century-Old Wisdom of Alexander Graham Bell.

    ERIC Educational Resources Information Center

    Cornett, Orin

    1990-01-01

    This article reflects on Alexander Graham Bell's 1888 testimony before the Royal Commission of the United Kingdom on the Condition of the Deaf and Dumb, Etc. Excerpts are grouped by reference to (1) language education for the hearing impaired; (2) speechreading; (3) methods of teaching; (4) speech; and (5) sign language. (Author/PB)

  17. Journalism and the Educational Views of Alexander Meiklejohn.

    ERIC Educational Resources Information Center

    Palmer, Mack R.

    Alexander Meiklejohn, who died in 1964 at the age of 92, was a constitutional scholar whose major interest was education. Among Meiklejohn's beliefs were the following: the social good should take precedence over individual achievement; the liberal arts college is the institution best suited to carry out an affirmative reading of the First…

  18. The Making of the Liberal College: Alexander Meiklejohn at Amherst.

    ERIC Educational Resources Information Center

    Brennan, Robert Thomas

    1988-01-01

    Surveys the history and curricular changes of Amherst College from its founding in 1821 through the administration of Alexander Meiklejohn in 1912. Assesses Meiklejohn's impact upon the development of Amherst as a liberal arts college, and analyses the events surrounding his dismissal. (SLM)

  19. 46. Photocopy of photograph (Pentran file), (from Alexander Brown's Peninsula's ...

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

    46. Photocopy of photograph (Pentran file), (from Alexander Brown's Peninsula's Last Street Cars, Daily Press, January 15, 1956) photographer unknown. The first streetcar (with dignitaries) to make the run from Newport News to a new housing development named Hilton Village in September 1918. - Newport News & Old Point Railway & Electric Company, Trolley Barn & Administration Building, 3400 Victoria Boulevard, Hampton, Hampton, VA

  20. A complex-network perspective on Alexander's wholeness

    NASA Astrophysics Data System (ADS)

    Jiang, Bin

    2016-12-01

    The wholeness, conceived and developed by Christopher Alexander, is what exists to some degree or other in space and matter, and can be described by precise mathematical language. However, it remains somehow mysterious and elusive, and therefore hard to grasp. This paper develops a complex network perspective on the wholeness to better understand the nature of order or beauty for sustainable design. I bring together a set of complexity-science subjects such as complex networks, fractal geometry, and in particular underlying scaling hierarchy derived by head/tail breaks - a classification scheme and a visualization tool for data with a heavy-tailed distribution, in order to make Alexander's profound thoughts more accessible to design practitioners and complexity-science researchers. Through several case studies (some of which Alexander studied), I demonstrate that the complex-network perspective helps reduce the mystery of wholeness and brings new insights to Alexander's thoughts on the concept of wholeness or objective beauty that exists in fine and deep structure. The complex-network perspective enables us to see things in their wholeness, and to better understand how the kind of structural beauty emerges from local actions guided by the 15 fundamental properties, and in particular by differentiation and adaptation processes. The wholeness goes beyond current complex network theory towards design or creation of living structures.

  1. View west of the James and Lucy Alexander gravestone and ...

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

    View west of the James and Lucy Alexander gravestone and family plot among other demarcated family plots in the Female Union Band Cemetery. - Mount Zion Cemetery/ Female Union Band Cemetery, Bounded by 27th Street right-of-way N.W. (formerly Lyons Mill Road), Q Street N.W., & Mill Road N.W., Washington, District of Columbia, DC

  2. The alexander surgical technique for the treatment of severe burns

    PubMed Central

    Gasperoni, M.; Neri, R.; Carboni, A.; Purpura, V.; Morselli, P.G.; Melandri, D.

    2016-01-01

    Summary The extensive loss of skin in burned patients is a critical clinical condition, and the choice of an effective technique to cover and protect the damaged area has always been a challenge in the surgical field. Despite its wide clinical use, there is little data in the literature on using the Alexander technique to treat severe burns, while several studies have focused on alternative approaches. The present study aims to evaluate the effectiveness of the Alexander surgical technique on 117 patients with severe burns. The characteristics of the burned patients, factors related to etiology of burns as well as adverse prognostic factors and their incidence in discharged versus deceased patients were also taken into account. Finally, a comparison is made with an alternative surgical procedure described in the literature. Our results show a satisfactory level of survival for patients with severe burns surgically treated with the Alexander technique, accounting for 63% of all clinical cases reported here. This treatment is also less expensive and more rapid than the alternative approach we compared it with. The Alexander technique is a lifesaving method for the treatment of severe burns that provides a satisfactory chance of survival at lower cost than the alternative surgical procedure examined. PMID:28289363

  3. Alexander Meiklejohn in Search of Freedom and Dignity.

    ERIC Educational Resources Information Center

    Johnson, Tony W.

    1982-01-01

    Assesses the contributions of the philosopher/educator Alexander Meiklejohn. Discusses the influences of Jean-Jacques Rousseau, Immanuel Kant, and the U.S. Constitution on Meiklejohn's educational theories, which stressed that human freedom and dignity can be enhanced by rigorous examination of U.S. Supreme Court decisions and the meaning of…

  4. Lamar Alexander and the Politics of School Reform.

    ERIC Educational Resources Information Center

    Kaplan, George R.

    1992-01-01

    Although U.S. Education Secretary Lamar Alexander's forceful presence on the educational scene has compelled attention and eclipsed his predecessors, we are a long way from knowing whether this consummate politician and his espoused causes (such as America 2000) are destined to make a serous difference in U.S. education. (MLH)

  5. Johann von Lamont: A Pioneer in Geomagnetism

    NASA Astrophysics Data System (ADS)

    Soffel, Heinrich

    2006-06-01

    The 200th birthday of John Lamont (1805-1879, Figure 1), a pioneer in the study of geomagnetism, was marked on 13 December 2005. Lamont founded the Munich Geomagnetic Observatory in 1840 and was a member of the group of scientists including Carl Friedrich Gauss, Alexander von Humboldt, Eduard Sabine, Jonas Angstrøm, Humphret Lloyd, Adolf Kupffer, Karl Kreil, and Adolphe Quetelet who composed the Göttingen Magnetic Union. They organized an international network of geomagnetic observatories [Barraclough et al., 1992]. The present knowledge of the geomagnetic field and its secular variation is largely based on the data collected by the global network of geomagnetic observatories during the last 170 years. Lamont's talents and his dedication and enthusiasm for discovery are reflected in the depth and scope of his contributions to a broad variety of natural sciences such as astronomy, meteorology, geomagnetism, and geodesy. However, this article just touches on his merits in geomagnetism.

  6. A Darwinian mystery: fluctuations in runoff from the la Plata basin (Alexander von Humboldt Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Clarke, R. T.

    2012-04-01

    During the voyage of HMS Beagle, Charles Darwin sailed in a small boat along the River Paraná, a major tributary of the la Plata drainage system. He wrote about the occurrence of severe droughts (the latest of which had been termed the "gran seco") alternating with periods of severe flooding. From reports received, he concluded that these events appeared to be cyclic with a period "of about fifteen years". Because extended periods of low flow in Brazilian rivers are of immense economic importance, the presentation describes a search for the material which led Darwin to this conclusion. A prolonged period of low flow in another la Plata tributary - the River Paraguay - not unlike the "gran seco" reported by Darwin, has occurred more recently; if such low flows were to recur in the future, the consequences would be severe for a region where more than 70% of energy is supplied by hydropower. A priori considerations suggest the use of statistical long-memory models for predicting River Paraguay water-levels, and some preliminary results from their use are presented.

  7. Brain and aviation: on the 80th anniversary of Constantin von Economo's (1876-1931) death.

    PubMed

    Sak, Jarosław; Grzybowski, Andrzej

    2013-03-01

    2011 marks the 80th anniversary of the death of Constantin Alexander von Economo who conducted advanced research on the cytoarchitectonics of the brain. This Austrian neurologist and the pioneer of aviation described encephalitis lethargica, discovered the spindle neurons, and postulated the existence of the sleep and wakefulness centre in the brain. What is more he realized two of the biggest dreams of humankind: conquering space and getting to know the secrets of the human brain.

  8. Nitric oxide mediates glial-induced neurodegeneration in Alexander disease.

    PubMed

    Wang, Liqun; Hagemann, Tracy L; Kalwa, Hermann; Michel, Thomas; Messing, Albee; Feany, Mel B

    2015-11-26

    Glia play critical roles in maintaining the structure and function of the nervous system; however, the specific contribution that astroglia make to neurodegeneration in human disease states remains largely undefined. Here we use Alexander disease, a serious degenerative neurological disorder caused by astrocyte dysfunction, to identify glial-derived NO as a signalling molecule triggering astrocyte-mediated neuronal degeneration. We further find that NO acts through cGMP signalling in neurons to promote cell death. Glial cells themselves also degenerate, via the DNA damage response and p53. Our findings thus define a specific mechanism for glial-induced non-cell autonomous neuronal cell death, and identify a potential therapeutic target for reducing cellular toxicity in Alexander disease, and possibly other neurodegenerative disorders with glial dysfunction.

  9. Alexander the Great and West Nile Virus Encephalitis

    PubMed Central

    Marr, John S.

    2003-01-01

    Alexander the Great died in Babylon in 323 BC. His death at age 32 followed a 2-week febrile illness. Speculated causes of death have included poisoning, assassination, and a number of infectious diseases. One incident, mentioned by Plutarch but not considered by previous investigators, may shed light on the cause of Alexander’s death. The incident, which occurred as he entered Babylon, involved a flock of ravens exhibiting unusual behavior and subsequently dying at his feet. The inexplicable behavior of ravens is reminiscent of avian illness and death weeks before the first human cases of West Nile virus infection were identified in the United States. We posit that Alexander may have died of West Nile encephalitis. PMID:14725285

  10. Dr Alexander Graham Bell--audiologist and speech therapist.

    PubMed

    Chakravorty, R C

    1976-09-01

    Alexander Graham Bell is best known for his role in the invention of the telephone. However, he had a lifelong involvement in speech therapy and audiology besides many other medical investigations. He was also awarded an honorary MD degree from Heidelberg University. In this, the 100th anniversary of his invention of the telephone, his life and some of his medical interests are briefly reviewed.

  11. Theodore von Karman

    NASA Technical Reports Server (NTRS)

    1926-01-01

    Theodore von Karman. NACA: In the eyes of most aeronautical experts, the overall record of Max Munk in aerodynamic research falls short of that achieved by fellow immigrant Theodore von Karman (the short man in the double breasted coat in the middle), shown here visiting Langley in December 1926. People in the photo include Max Munk, aerodynamic researcher; Theodore von Karman; George Lewis, director of research; Henry Reid, engineer in charge; Fred Weick, PRT head; Paul Hemke; Elliott Reid, future Stanford University Professor.

  12. Living with von Willebrand Disease

    MedlinePlus

    ... from the NHLBI on Twitter. Living With von Willebrand Disease If you have von Willebrand disease (VWD), you ... that they get tested too. Pregnancy and von Willebrand Disease Pregnancy can be a challenge for women who ...

  13. >From alexander of aphrodisias to young and airy

    NASA Astrophysics Data System (ADS)

    Jackson, J. D.

    1999-10-01

    A didactic discussion of the physics of rainbows is presented, with some emphasis on the history, especially the contributions of Thomas Young nearly 200 years ago. We begin with the simple geometrical optics of Descartes and Newton, including the reasons for Alexander's dark band between the main and secondary bows. We then show how dispersion produces the familiar colorful spectacle. Interference between waves emerging at the same angle, but traveling different optical paths within the water drops, accounts for the existence of distinct supernumerary rainbows under the right conditions (small drops, uniform in size). Young's and Airy's contributions are given their due.

  14. In memoriam. Alexander Hollaender 1898-1986. [Radiobiology

    SciTech Connect

    Not Available

    1987-01-01

    Alexander Hollaender gave an early clue that there might be recovery or repair mechanisms in bacteria, although at the time the target for cell target for cell killing was not known. As one of the early investigators who used action spectra for the identification of the targets in biological systems, he was able to show that the wavelengths producing mutations were just those absorbed by nucleic acids, even though in those days nucleic acids were not known to be the genetic material. This result was the first clear indication that radiation and environmental biologists should concentrate on changes in DNA and not in proteins.

  15. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (left) and Fred W. Kelley examine a ST-100 Stellar Instrument Platform in the astrionics lab. Dr. Von Braun, then deputy associate administrator for planning, NASA, was visiting on the anniversary of the establishment of the Marshall Space Flight Center.

  16. CSF and Blood Levels of GFAP in Alexander Disease

    PubMed Central

    Jany, Paige L.; Agosta, Guillermo E.; Benko, William S.; Eickhoff, Jens C.; Keller, Stephanie R.; Köehler, Wolfgang; Mar, Soe; Naidu, Sakkubai; Marie Ness, Jayne; Renaud, Deborah L.; Salsano, Ettore; Schiffmann, Raphael; Simon, Julie; Vanderver, Adeline; Eichler, Florian; van der Knaap, Marjo S.

    2015-01-01

    Abstract Alexander disease is a rare, progressive, and generally fatal neurological disorder that results from dominant mutations affecting the coding region of GFAP, the gene encoding glial fibrillary acidic protein, the major intermediate filament protein of astrocytes in the CNS. A key step in pathogenesis appears to be the accumulation of GFAP within astrocytes to excessive levels. Studies using mouse models indicate that the severity of the phenotype correlates with the level of expression, and suppression of GFAP expression and/or accumulation is one strategy that is being pursued as a potential treatment. With the goal of identifying biomarkers that indirectly reflect the levels of GFAP in brain parenchyma, we have assayed GFAP levels in two body fluids in humans that are readily accessible as biopsy sites: CSF and blood. We find that GFAP levels are consistently elevated in the CSF of patients with Alexander disease, but only occasionally and modestly elevated in blood. These results provide the foundation for future studies that will explore whether GFAP levels can serve as a convenient means to monitor the progression of disease and the response to treatment. PMID:26478912

  17. [Alexander Borodin--physician, chemist, scientist, teacher and composer].

    PubMed

    Vik, T

    1998-12-10

    Concert programmes and CD covers suggest that the Russian composer Alexander Borodin (1833-87) was also a great scientist. In this article we examine this proposition. Borodin was born in St. Petersburg as the illegitimate son of a Russian nobleman. As a boy his talents ranged from music to chemistry and languages. Borodin studied medicine at the Medico-Surgical Academy in St. Petersburg from 1850 to 1855 and defended his doctoral thesis on the similarity between arsenic and phosphoric acid in 1858. He did not, however, feel comfortable in his role as a doctor, and soon started to work as a chemist. In 1864 he was appointed professor of chemistry at the Medico-Surgical Academy. In 1861, Borodin attended the first international congress of chemistry in Karlsruhe, and he was among the founders of the Russian Chemical Society in 1868. He published 42 articles and was a friend of Dmitri Mendeleev, the scientist who described the periodic system. In 1872, Borodin started the first medical courses for women in Russia. It seems warranted to conclude that Alexander Borodin was indeed a great scientist and university teacher, though his immortality was earned by his leisure time activities.

  18. Dr. Wernher von Braun

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Dr. von Braun is looking out from a 10th floor window of building 4200 at the Marshall Space Flight Center (MSFC). He was the first Center Director and served as the Director from July 1960 through February 1970. Following World War II, Dr. von Braun and his German colleagues arrived in the United States under the Project Paperclip (American acquisition of German rocket experts) to continue their rocket development work. In 1950, von Braun and his German Rocket Team (also called the Peenemuende Team) were transferred from Ft. Bliss, Texas to Huntsville, Alabama to work for the Army's rocket program at Redstone Arsenal and later, NASA's Marshall Space Flight Center (MSFC). Under Dr. von Braun's leadership, MSFC developed the Saturn V launch vehicle, which placed the first men, two American astronauts, on the Moon. Wernher von Braun's life was dedicated to expanding man's knowledge through the exploration of space.

  19. Kinesthetic Ventures Informed by the Work of F. M. Alexander, Stanislavski, Peirce, and Freud.

    ERIC Educational Resources Information Center

    Bouchard, Ed; Wright, Ben; Protzel, Michael, Ed.

    This book is about education harvested from self-observation. F. Matthias Alexander (1869-1955) studied the experience of self formation, working with motor habits. His method is used in performing arts training to enhance bodily and vocal expression. Like Alexander, Konstantine Stanislavski (1863-1938) and Sigmund Freud (1856-1939) studied human…

  20. 76 FR 28226 - Ndahendekire Barbara v. African Shipping; Njoroge Muhia; Alco Logistics, Llc; Brenda Alexander...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-16

    ... Ndahendekire Barbara v. African Shipping; Njoroge Muhia; Alco Logistics, Llc; Brenda Alexander; and AIR 7 Seas... ``Complainant,'' against African Shipping; Njoroge Muhia, ALCO Logistics, LLC; Brenda Alexander; and Air 7 Seas Transport Logistics, Inc.; hereinafter ``Respondents''. Complainant asserts that she is acting agent...

  1. The death of Alexander the Great--a spinal twist of fate.

    PubMed

    Ashrafian, Hutan

    2004-06-01

    Alexander the Great died in 323 B.C. from an unknown cause. Physical depictions of this historical figure reveal the likelihood of a cervical scoliotic deformity. This is substantiated with the medical history and is correlated with his untimely death. For the first time, it is concluded that Alexander's death may have ensued from the sequelae of congenital scoliotic syndrome.

  2. von Willebrand Disease.

    PubMed

    Swami, Arjun; Kaur, Varinder

    2016-01-01

    von Willebrand disease (vWD) is the most common inherited disorder of hemostasis and comprises a spectrum of heterogeneous subtypes. Significant advances have been made in understanding von Willebrand factor ( vWF) gene mutations, resultant physiologic deficits in the vWF peptide, and their correlation to clinical presentation. Diagnostic tests for this disorder are complex, and interpretation requires a thorough understanding of the underlying pathophysiology by the practicing physician. The objective of this review is to summarize our current understanding of pathophysiology, laboratory investigations, and evolving treatment paradigm of vWD with the availability of recombinant von Willebrand factor.

  3. Teaching Nuclear Radiation and the Poisoning of Alexander Litvinenko

    NASA Astrophysics Data System (ADS)

    Lapp, David R.

    2008-03-01

    The recent international story about the death of the former KGB agent Alexander Litvinenko has more than just a few wondering about radiation poisoning and the sinister sounding polonium-210. I was preparing to begin a nuclear radiation unit the Monday after Thanksgiving 2006. As it turned out, Litvinenko died Thanksgiving Day after a short and terrible three-week illness. Having the story continue to unfold throughout the next two weeks of the new unit provided a daily opportunity for students to see the relevance of what we were doing in class. My students were able to have meaningful and informed conversations with their peers and parents over an important international event. They even began to feel a bit like authorities themselves when listening to experts respond to media questions about polonium-210 and nuclear radiation in general. This paper discusses some of the ways that the story of Litvinenko was used while presenting the topic of nuclear radiation.

  4. The Astronomer Alexander I. Postoiev (1900-1976)

    NASA Astrophysics Data System (ADS)

    Dos Santos, P. M.; Matsuura, O. T.

    This is a biographical note on the life of Dr Alexander I. Postoiev, a victim of Stalin's purge of Soviet astronomers in 1936-1937 (McCutcheon, 1985). Along with his family, he left the Soviet Union in 1943, and lived in Germany as a refugee and "displaced person" until 1952, when he moved to Brazil. Then he started the second part of his professional career. Thanks to his efforts the Astronomical and Geophysical Institute (IAG) from the University of Sao Paulo (USP) was involved, for the first time, in programme of international cooperation, thus contributing to the institutional consolidation of IAG/USP as a leading centre of astronomical research and teaching today in Brazil.

  5. Silurian Gastropoda from the Alexander terrane, southeast Alaska

    USGS Publications Warehouse

    Rohr, D.M.; Blodgett, R.B.

    2008-01-01

    Gastropods are described from Ludlow-age strata of the Heceta Limestone on Prince of Wales Island, southeast Alaska. They are part of a diverse megabenthic fauna of the Alexander terrane, an accreted terrane of Siberian or Uralian affinities. Heceta Limestone gastropods with Uralian affinities include Kirkospira glacialis, which closely resembles "Pleurotomaria" lindstromi Oehlert of Chernyshev, 1893, Retispira cf. R. volgulica (Chernyshev, 1893), and Medfracaulus turriformis (Chernyshev, 1893). Medfracaulus and similar morphotypes such as Coelocaulus karlae are unknown from rocks that are unquestionably part of the North American continent (Laurentia) during Late Silurian time. Beraunia is previously known only from the Silurian of Bohemia. Pachystrophia has previously been reported only from western North American terranes (Eastern Klamath, York, and Farewell terranes) and Europe. Bathmopterus Kirk, 1928, is resurrected and is only known from the Silurian of southeast Alaska. Newly described taxa include Hecetastoma gehrelsi n. gen. and n. sp. and Baichtalia tongassensis n. gen. and n. sp. ??2008 The Geological Society of America.

  6. Adaptive autophagy in Alexander disease-affected astrocytes.

    PubMed

    Tang, Guomei; Yue, Zhenyu; Tallóczy, Zsolt; Goldman, James E

    2008-07-01

    The ubiquitin-proteasome and autophagy-lysosomal pathways are the two main routes of protein and organelle clearance in eukaryotic cells. The proteasome system is responsible for unfolded, short-lived proteins, which precludes the clearance of oligomeric and aggregated proteins, whereas macroautophagy, a process generally referred to as autophagy, mediates mainly the bulk degradation of long-lived cytoplasmic proteins, large protein complexes or organelles.(1) Recently, the autophagy-lysosomal pathway has been implicated in neurodegenerative disorders as an important pathway for the clearance of abnormally accumulated intracellular proteins, such as huntingtin, tau, and mutant and modified α-synuclein.(1-6) Our recent study illustrated the induction of adaptive autophagy in response to mutant glial fibrillary acidic protein (GFAP) accumulation in astrocytes, in the brains of patients with Alexander disease (AxD), and in mutant GFAP knock-in mouse brains.(7) This autophagic response is negatively regulated by mammalian target of rapamycin (mTOR). The activation of p38 MAPK by GFAP accumulation is responsible for mTOR inactivation and the induction of autophagy. We also found that the accumulation of GFAP impairs proteasome activity.(8) In this commentary we discuss the potential compensatory relationship between an impaired proteasome and activated autophagy, and propose that the MLK-MAPK (mixed lineage kinase-mitogen-activated protein kinase) cascade is a regulator of this crosstalk. Addendum to: Tang G, Yue Z, Talloczy, Z, Hagemann T, Cho W, Sulzer D, Messing A, Goldman JE. Alexander disease-mutant GFAP accumulation stimulates autophagy through p38 MAPK and mTOR signaling pathways. Hum Mol Genetics 2008; In press.

  7. Von Willebrand disease

    MedlinePlus

    ... done to diagnose this disease include: Bleeding time Blood typing Factor VIII level Platelet function analysis Platelet count Ristocetin cofactor test Von Willebrand factor specific tests ... invasive procedure. Blood plasma or certain factor VIII preparations may also ...

  8. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (right), Deputy Associate Administrator for planning, National Aeronautics and Space Administration, inspects the mockup of the Saturn Workshop during a visit marking the 10th anniversary of the Marshall Center. Shown with Dr. Von Braun, from left to right, are Karl Heimburg, Director of the astronautics lab; Herman K. Weidner, Director of Science and Engineering, and George Hardy of the Astronautics lab.

  9. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (right), Deputy Associate Administrator for Planning, National Aeronautics and Space Administration, inspects the mockup of the Saturn Workshop during a visit marking the 10th anniversary of the Marshall Center. Shown with Dr. Von Braun, from left to right, are Karl Heimburg, Director of the Astronautics Lab; Herman K. Weidner, Director of Science and Engineering, and George Hardy of the Astronautics Lab.

  10. The Berlin tradition in Chicago: Franz Alexander and the Chicago Institute for Psychoanalysis.

    PubMed

    Schmidt, Erika S

    2010-01-01

    Freud considered Franz Alexander, the first graduate of the Berlin Psychoanalytic Institute and an assistant in the Berlin Polyclinic, to be "one of our strongest hopes for the future." Alexander went on to become the first director of the Chicago Institute for Psychoanalysis in 1932 and modeled some of the Chicago Institute's mission on his Berlin experiences. He was also a researcher in psychosomatic medicine, a prolific writer about psychoanalysis and prominent in psychoanalytic organizations. As he proposed modifications in psychoanalytic technique, he became a controversial figure, especially in the elaboration of his ideas about brief therapy and the corrective emotional experience. This paper puts Alexander's achievements in historical context, draws connections between the Berlin and Chicago Institutes and suggests that, despite his quarrels with traditional psychoanalysis, Alexander's legacy may be in his attitude towards psychoanalysis, characterized by a commitment to scientific study, a willingness to experiment, and a conviction about the role of psychoanalysis within the larger culture.

  11. Expedition 8 Crew Interviews: Alexander Y. Kaleri - FE

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Russian cosmonaut Alexander Y. Kaleri, Flight Engineer on Expedition 8 to the International Space Station (ISS), answers interview questions on this video, either himself or with the help of an interpreter. The questions cover: 1) The goal of the expedition; 2) The place in history of Mir; 3) The reaction to the loss of Columbia in Houston; 4) Why the rewards of spaceflight are worth the risks; 5) Why he decided to become a cosmonaut; 6) His memory of Yuri Gagarin's first flight; 7) What happens on a Soyuz capsule during launch and flight; 8) Are Soyuz maneuvers automatic or manual; 8) How the ISS science mission will be advanced during his stay; 9) The responsibilities of a Flight Engineer onboard the ISS; 10) Extravehicular activity (EVA) plans at that time; 11) The Shuttle Return to Flight and his preference for a Shuttle or Soyuz landing; 12) Why the last Soyuz landing was too rough; 13) The most valueable contribution of the ISS program.

  12. Personal reflections on the life and legacy of Alexander Hollaender.

    PubMed

    Gaulden, Mary Esther; Jagger, John; White, Virginia P

    2007-01-01

    Mary Esther Gaulden presents a personal summary of the activities of Alexander Hollaender, from his days at the National Institutes of Health to his becoming Director of the Biology Division of the Oak Ridge National Laboratory in 1947. This appealing story deals with many of her reactions to his personality and organizational style. It reflects the atmosphere of science in those days, and her enthusiasm in this vibrant milieu. Next is a brief account by John Jagger of his first meeting with Dr. Hollaender, arrival in Oak Ridge in April 1956, and wedding to Mary Esther six months later at the house of the Hollaenders in Oak Ridge. The third section is an account by Virginia P. White of how she came to Oak Ridge in 1955 and became Dr. Hollaender's Laboratory Administrator. She gives a personal account of the many facets of his managerial style, as well as of the personality of his wife, Henrietta. She also describes one of Hollaender's many avocations, the collection of fossils on Sunday morning hikes in the Cumberland Mountains, accompanied by lab and visiting personnel, and finally comments on the annual research conferences in Gatlinburg TN, for which Hollaender and the lab became very well known, with some closing vignettes on his leadership style.

  13. Alexander Robertson (1834-1908): Glasgow's pioneer aphasiologist and epileptologist.

    PubMed

    Eadie, Mervyn

    2015-01-01

    Alexander Robertson (1834-1908) was a Glasgow physician whose professional career was involved mainly with institutional-based practice but who published significant insights into the anatomical background to aphasia (1867) and the mechanisms of focal epileptogenesis (1869). His aphasiology ideas, including his suggestion that disconnection between cerebral centers involved in speech was responsible for the phenomenon, made him one of the earliest members of the late-nineteenth-century school of aphasia diagram makers. His view of epileptogenesis was that contralateral convulsing arose from irritation in a local area of pathology on the surface of the cerebral cortex after the irritation spread to a cortical motor center and then down the motor pathway to the striatum, while spreading within the cortex itself caused loss of consciousness. This interpretation contains much of the essence of the present-day understanding of cortical epileptogenesis. The origin of this interpretation is often attributed to John Hughlings Jackson, but Robertson published the idea in full a year or two prior to Jackson. However, Robertson's original insights were hardly noticed at the time they were published and have since almost entirely been ignored.

  14. Alexander Forbes, Walter Cannon, and science-based literature.

    PubMed

    Garson, Justin

    2013-01-01

    The Harvard physiologists Alexander Forbes (1882-1965) and Walter Bradford Cannon (1871-1945) had an enormous impact on the physiology and neuroscience of the twentieth century. In addition to their voluminous scientific output, they also used literature to reflect on the nature of science itself and its social significance. Forbes wrote a novel, The Radio Gunner, a literary memoir, Quest for a Northern Air Route, and several short stories. Cannon, in addition to several books of popular science, wrote a literary memoir in the last year of his life, The Way of an Investigator. The following will provide a brief overview of the life and work of Forbes and Cannon. It will then discuss the way that Forbes used literature to express his views about the changing role of communications technology in the military, and his evolving view of the nervous system itself as a kind of information-processing device. It will go on to discuss the way that Cannon used literature to articulate the horrors he witnessed on the battlefield, as well as to contribute to the philosophy of science, and in particular, to the logic of scientific discovery. Finally, it will consider the historical and philosophical value of deeper investigation of the literary productions of scientists.

  15. von Willebrand factor and von Willebrand disease.

    PubMed

    Matsui, Taei; Hamako, Jiharu

    von Willebrand factor (VWF) has two major roles in hemostasis, as a form of molecular glue which functions in platelet plug formation and as a protective transporter for coagulation factor VIII (FVIII). VWF shows a multimeric chain structure composed of 270 kDa subunits containing binding domains for FVIII, platelet and collagens. Biosynthesis, storage, secretion of VWF and the cleavage process by ADAMTS13 (a disintegrin-like and metalloproteinase with thrombospondin type 1 repeats 13) regulating VWF activity have been elucidated. von Willebrand disease (VWD) is an autosomal bleeding disorder, first documented in 1926, caused by quantitative or qualitative deficiency of VWF. The classification and molecular pathogenesis of VWD have been developed during a 90-year period based on clinical laboratory analysis of VWF, and structure-function analysis of mutant VWF with amino acid substitutions (genetic changes). VWF is a unique and very large multifunctional plasma protein, the hemostatic activity of which is dynamically regulated by physiological shear stress in the blood stream.

  16. Energetische Verwertung von Biomasse

    NASA Astrophysics Data System (ADS)

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

    Etwa 0,1% der Solarenergie wandeln sich durch Photosynthese aus dem Kohlendioxid der Luft in Biomasse um. Die Biomassen sind als Festbrennstoff nutzbar oder zu gasförmigen Brennstoffen weiterverarbeitbar. Zwei Arten von Biomassen sind zu unterscheiden: Anfallende Biomasse

  17. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Shown viewing the Apollo telescope mockup are, from left to right, Charles Donlan, deputy associate administrator for manned space flight; Dr. Wernher Von Braun, Marshall Space Flight Center director; William Horton, astrionics lab; Dr. Thomas Paine, NASA deputy administrator; Warner Kuers, director of the ME lab.

  18. Increased dynamic regulation of postural tone through Alexander Technique training

    PubMed Central

    Cacciatore, TW; Gurfinkel, VS; Horak, FB; Cordo, PJ; Ames, KE

    2010-01-01

    Gurfinkel and colleagues (2006) recently found that healthy adults dynamically modulate postural muscle tone in the body axis during anti-gravity postural maintenance and that this modulation is inversely correlated with axial stiffness. Our objective in the present study was to investigate whether dynamic modulation of axial postural tone can change through training. We examined whether teachers of the Alexander Technique (AT), who undergo “long-term” (3-year) training, have greater modulation of axial postural tone than matched control subjects. In addition, we performed a longitudinal study on the effect of “short-term” (10-week) AT training on the axial postural tone of individuals with low back pain (LBP), since short term AT training has previously been shown to reduce LBP. Axial postural tone was quantified by measuring the resistance of the neck, trunk and hips to small (±10°), slow (1°/s) torsional rotation during stance. Modulation of tone was determined by the torsional resistance to rotation (peak-to-peak, phase-advance, and variability of torque) and axial muscle activity (EMG). Peak-to-peak torque was lower (~50%), while phase-advance and cycle-to-cycle variability were enhanced for AT teachers compared to matched control subjects at all levels of the axis. In addition, LBP subjects decreased trunk and hip stiffness following short-term AT training compared to a control intervention. While changes in static levels of postural tone may have contributed to the reduced stiffness observed with the AT, our results suggest that dynamic modulation of postural tone can be enhanced through long-term training in the AT, which may constitute an important direction for therapeutic intervention. PMID:21185100

  19. The life and death of Alexander Bogdanov, physician.

    PubMed

    Huestis, D W

    1996-08-01

    It was early in April in 1928 when the word went out in Moscow that Alexander Bogdanov had died. He was a controversial figure, an old Bolshevik who had left that party long before the 1917 revolution and never returned. All the same, he had had Lenin's respect as a scientist (as long as he stayed out of politics). More recently, he also had the support of the new party strong man, Stalin. Bogdanov opposed the growing despotism of the "dictatorship of the proletariat", under which slogan Communist autocracy was being developed. But he was respected as a tireless propagandist for the socialist cause, an enthusiastic teacher of the proletariat, and a writer of arcane science and philosophy. Bogdanov was held in such respect that Communist bigwigs spoke glowingly at the funeral, praising his intellect, courage, and dedication to science and humanity. They did not fail to point out that he had split with his one-time friend, Lenin, and had succumbed to ideological "errors". Indeed, he had powerful enemies in the early Soviet state. Bogdanov was a physician, economist, philosopher, natural scientist, writer of utopian science fiction, poet, teacher, politician (unsuccesful), lifelong revolutionary, forerunner of what we now call cybernetics and organizational science, and founder of the world's first institution devoted entirely to the field of blood transfusion. You could call him a Renaissance man. Although he clearly fitted the category of the late-nineteenth-century Russian intellectual revolutionary, Bogdanov differed from most of them in being no dilettante. More than just a theorist, he was an active scientist and physician. As a teacher, he firmly believed that education and indoctrination could alter people's ways of thinking and behaving, and that humanity could be perfected under socialism. Like many revolutionaries, Bogdanov tried to keep ahead of the Tsar's police by using a variety of pseudonyms, among them Riadavoy, Werner, Maximov, and Bogdanov. After

  20. Cyclicity in Silurian island-arc carbonates, Alexander terrane, Alaska

    SciTech Connect

    Kittredge, L.E.; Soja, C.M. . Dept. of Geology)

    1993-03-01

    Silurian carbonates from Alaska (Alexander terrane) record the evolution of a submarine platform during waning volcanism in an island arc. A detailed stratigraphic analysis of a 47 meter-thick sequence revealed the existence of cyclically repeated limestones: coral-stromatoporoid wackestones alternate with oncoid packstones and bioturbated, silty lime mudstones. The coral-stromatoporoid deposits are characterized by a low-diversity assemblage of dendroid corals, massive stromatoporoids, Atrypoidea brachiopods, and rare occurrences of biostromes associated with Solenopora, high-spired gastropods, and crinoids. Oncoids typically are 2-6 mm in diameter and form massive, meter-thick units. Coated grains are symmetrically developed, have a shell or algal nucleus, and are also a minor component of coral-stromatoporoid beds. These lithologic units form seven, shallowing-upwards cycles (parasequences) that range in thickness from 3-9 meters. Coral-stomatoporoid wackestones form the base of each cycle and grade upwards into oncoid packstones with silty, lime mudstones at the top. This succession of lithofacies within each cycle reflects an increase in energy levels from relatively deeper water environments to relatively shallower ones. The lack of abrasion in the corals and stromatoporoids suggests predominantly quiet-water conditions in shallow subtidal areas affected by periodic turbulence. Comparison with correlative sections in Alaska and lack of correspondence with global sea level curves suggest that the primary cause of cyclicity was tectonic perturbations with secondary eustatic effects. Cyclic deposition in peri/subtidal sites was terminated by rapid drowning of the carbonate platform during late Silurian orogenesis.

  1. Is research on soil erosion hazard and mitigation in the Global South still needed? (Alexander von Humbold Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Poesen, Jean

    2016-04-01

    Soil erosion represents a geomorphological and geological hazard that may cause environmental damage (land degradation), property damage, loss of livelihoods and services as well as social and economic disruption. Erosion not only lowers the quality of our soils on site, resulting in a drastic reduction of their ecosystem functions that play a vital role in daily life, but causes also significant sediment-related problems off site. To curb soil erosion problems, a range of soil conservation techniques and strategies have been designed and are being applied. Worldwide, ca. 62 000 research papers on soil erosion and 116 000 on soil conservation have been published (Web of Science, Dec. 2015). The number of such papers dealing with the Global South represents less than 20 % of all papers, despite the fact that many regions in this part of the world face significant soil erosion problems, aggravated by a rapidly growing population and major environmental changes. Given the large number of research papers on this topic, one might therefore conclude that we now know almost everything about the various soil erosion processes and rates, their factors and consequences as well as their control so that little new knowledge can still be added to the vast amount of available information. We refute this conclusion by pointing to some major research gaps that still need to be addressed if we want to use our soils in a more sustainable way. More specifically the following topics need more research attention: 1) improved understanding of both natural and anthropogenic soil erosion processes and their interactions, 2) scaling up soil erosion processes and rates in space and time, and 3) innovative techniques and strategies to prevent or reduce erosion rates. This will be illustrated with case studies from the Global South. If future research focuses on these research gaps, we will 1) better understand processes and their interactions operating at a range of spatial and temporal scales, their rates as well as their on-site and off-site impacts, which is crucial for better targeting erosion control measures and which is academically spoken rewarding, and 2) we will also be in a better position to select the most appropriate and effective soil erosion control techniques and strategies which are badly needed for a sustainable use of our soils in the Anthropocene and for the improvement of environmental conditions worldwide.

  2. Analyse und Entwurf von hochbitratigen Clock-and-Data-Recovery Schaltungen in CMOS-Technologie

    NASA Astrophysics Data System (ADS)

    Bremer, J.-K.; Zemko, C.; Schmackers, J.; Mathis, W.

    2007-06-01

    In dieser Arbeit wird ein neuartiges Schaltungskonzept für die Realisierung eines Phasendetektors einer Clock-and-Data-Recovery Schaltung vorgestellt. Es handelt sich hierbei um eine nichtlineare Phasendetektorarchitektur, die nach dem Verfahren von Alexander arbeitet. Um die Funktionalität des Phasendetektors im Hochfrequenzbereich zu gewährleisten, wurden in dem Design sehr schnell schaltende HLO-Flip-Flops (high-speed latching operation flip-flop) verwendet. Ein wesentliches Entwurfsziel war die Begrenzung des selbstgenerierten Jitters des Phasendetektors. Der Schaltungsentwurf wurde mit der Simulationsumgebung Cadence Spectre durchgeführt und die Funktionalität der Schaltung im GHz-Bereich anhand von ausgewählten Simulationen verifiziert. This paper presents a novel realization concept for Clock-and-Data-Recovery circuits. Our Design uses a nonlinear phase detector architecture, which is based on the Alexander phase detection method. In order to ensure circuit functionality in the RF region, we use very fast switching HLO-Flip-Flops (high-speed latching operation flip-flop) in our design. The primal goal in our design was the minimization of self induced jitter of the phase detector. The accuracy of our circuit design and the functionality in the GHz regime is confirmed by various circuit simulations executed with the SPECTRE Simulator.

  3. An adult form of Alexander disease: a novel mutation in glial fibrillary acidic protein.

    PubMed

    Ohnari, K; Yamano, M; Uozumi, T; Hashimoto, T; Tsuji, S; Nakagawa, M

    2007-10-01

    Glial fibrillary acidic protein (GFAP) mutation has been reported in Alexander disease. We report a patient with the adult form of Alexander disease who shows a novel mutation in GFAP. This case presented with progressive dysarthria, dysphagia and spastic gait on the right side. Brain and spinal cord MRI showed marked atrophy of the medulla oblongata and spinal cord. Abnormal high signal intensities in the ventral medulla oblongata were detected bilaterally. There were no white matter lesions or contrast enhancing lesions. Recently, there have been reports of patients with a juvenile form of Alexander disease presenting with atrophy or signal abnormalities of the medulla or spinal cord. Atrophy of the medulla and spinal cord have specifically been described as suggestive of Alexander disease [1]. Sequence analysis of the GFAP gene of this patient showed a heterozygous c.221T>C mutation, predicting a p.M74T amino acid change. In all patients suspected of Alexander disease on the basis of MRI findings, GFAP analysis is necessary to confirm the diagnosis.

  4. Obituary: Alexander (Andy) Franz Lubenow, 1956-2005

    NASA Astrophysics Data System (ADS)

    Buie, Marc William

    2006-12-01

    Alexander (Andy) Franz Lubenow, Program Coordinator at the Space Telescope Science Institute, was diagnosed with cancer of the gallbladder, pancreas, and liver in May 2005 and died on 29 September 2005. He was forty-nine. Andy was born to Bodo and Helen Lubenow in St. Paul, Minnesota on 4 January 1956. In 1964 at the age of eight, he moved with his family to Buenos Aires, Argentina, and attended the American Community School there until returning with his family in 1973 to St. Paul. Argentina had a big impact on Andy's future as an astronomer. He later recalled how he had observed and was puzzled by the "upside-down" appearance of the Moon in the southern hemisphere. In Argentina, he built his first telescope using a mirror he had ground himself. He never parted ways with that instrument. Andy did not follow a standard educational track. He spent two years at St. Olaf College in Northfield, Minnesota, before transferring to the University of Minnesota, where he earned his bachelor's degree and began work towards a master's degree in astrophysics. Later he transferred to the University of Illinois at Urbana-Champaign, where he remained until Dr. Peter Stockman hired him to work on the Hubble Space Telescope project. While in school, he worked as a teacher's assistant, taught night school, and gave demonstrations of stargazing. He was an excellent teacher and had a flair for writing. He later wrote articles for a sailing magazine and a pilot's magazine. Andy was a very practical, meticulous, and steady worker, attributes that he combined with an understated and dry sense of humor. He was always able to find a way through a problem, no matter how sticky. If a job required him to roll up his sleeves and get it done through hard work, he would persevere. Nevertheless, he was always on the lookout for an easier way. He had no patience for being forced to deal with stupid things for stupid reasons. At work at the Space Telescope Science Institute (STScI), Andy was

  5. Samuel Alexander Kinnier Wilson. Wilson's disease, Queen Square and neurology.

    PubMed

    Broussolle, E; Trocello, J-M; Woimant, F; Lachaux, A; Quinn, N

    2013-12-01

    This historical article describes the life and work of the British physician Samuel Alexander Kinnier Wilson (1878-1937), who was one of the world's greatest neurologists of the first half of the 20th century. Early in his career, Wilson spent one year in Paris in 1903 where he learned from Pierre-Marie at Bicêtre Hospital. He subsequently retained uninterrupted links with French neurology. He also visited in Leipzig the German anatomist Paul Flechsig. In 1904, Wilson returned to London, where he worked for the rest of his life at the National Hospital for the Paralysed and Epileptic (later the National Hospital for Nervous Diseases, and today the National Hospital for Neurology and Neurosurgery) in Queen Square, and also at Kings' College Hospital. He wrote on 'the old motor system and the new', on disorders of motility and muscle tone, on the epilepsies, on aphasia, apraxia, tics, and pathologic laughing and crying, and most importantly on Wilson's disease. The other objective of our paper is to commemorate the centenary of Wilson's most important work published in 1912 in Brain, and also in Revue Neurologique, on an illness newly recognized and characterized by him entitled "Progressive lenticular degeneration, a familial nervous disease associated with liver cirrhosis". He analyzed 12 clinical cases, four of whom he followed himself, but also four cases previously published by others and a further two that he considered in retrospect had the same disease as he was describing. The pathological profile combined necrotic damage in the lenticular nuclei of the brain and hepatic cirrhosis. This major original work is summarized and discussed in the present paper. Wilson not only delineated what was later called hepato-lenticular degeneration and Wilson's disease, but also introduced for the first time the terms extrapyramidal syndrome and extrapyramidal system, stressing the role of the basal ganglia in motility. The present historical work emphasizes the special

  6. IN MEMORIAM: In Memoriam: Alexander A Golovin and Alexei M Oparin In Memoriam: Alexander A Golovin and Alexei M Oparin

    NASA Astrophysics Data System (ADS)

    2008-10-01

    In Memoriam of Alexander A Golovin (1962-2008) Alexander (Sasha) Golovin passed away on 10 September 2008. Sasha's scientific heritage includes seminal works in different fields of physics, from Marangoni convection to self-assembly of quantum dots, and from combustion fronts to anomalous diffusion in flows and on a crystal surface. A graduate of the Moscow Institute for Physics and Technology, he had very broad scientific interests and a unique ability to identify and solve new, intellectually challenging and technologically important problems. One of the basic fields of Sasha's research was the fluid dynamics in systems with interfaces. His favorite subject was the motion of droplets, bubbles and particles in the presence of heat and mass transfer. Sasha's early works contained the discovery of the spontaneous motion of droplets due to the Marangoni effect and the investigation of the interaction between solid particles, bubbles and droplets caused by the Marangoni effect, which is a crucial factor that determines the effect of heat/mass transfer on the rate of coalescence. In both cases, Sasha's work was the first in a long sequence of papers written by different authors. Later, Sasha returned to that field when studying such fascinating subjects as levitation of droplets above the surface of an evaporating liquid and encapsulation of particles and bubbles by an advancing solidification front. The subject of interfacial hydrodynamics overlaps with another basic field of Sasha's research, the theory of pattern formation. The contribution of Sasha's work to the modern understanding of the variety of pattern formation phenomena is significant. It includes the analysis of the interaction between long-wave and short-wave instability modes in Marangoni convection, investigation of the large-scale Marangoni convection that led to the prediction of different patterns including quasipatterns, and the description of various non-potential effects in Marangoni convection

  7. Von Karman swirling flows

    NASA Astrophysics Data System (ADS)

    Zandbergen, P. J.; Dijkstra, D.

    A development history is presented for research on the problem of swirling flow infinite disks from its formulation by von Karman in 1921 through the treatments of Batchelor (1951) and Stewartson (1953) to the present, with a view to both its one-disk and two-disk forms. Attention is given to the stability of the stationary solutions for these problems, and to the case where the radii of the disks are finite. The question as to the extent to which the Karman swirling flow occurs in a finite radial geometry is noted to be of fundamental importance.

  8. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Thomas Paine, Deputy Administrator of the National Aeronautics and Space Administration, examines an ordinary man's shoe outfitted for use in the Saturn I workshop. Pictured from the left in the Saturn I workshop mockup are William Brooksbank, propulsion and vehicle engineering laboratory; Dr. Paine; Dr. Wernher Von Braun, Marshall Center director; Colonel Clare F. Farley, Executive Officer in the Office Of The Administrator; and Charles J. Donlan, Deputy Associate Administrator for Manned Space Flight, Technical. the shoe Dr. Paine is holding has a unique fastener built into the sole to allow an astronaut to move about on the workshop floor and to remain in one position if he desires.

  9. von Willebrand Disease (For Parents)

    MedlinePlus

    ... problems because the levels or functioning of these blood components needed for clotting are abnormal. continue Types of von Willebrand Disease As with many conditions, there are various forms ... of von Willebrand factor in the blood is reduced; the level of factor VIII also ...

  10. Old Age, the Ancient Military, and Alexander's Army: Positive Examples for a Graying America.

    ERIC Educational Resources Information Center

    Kebric, Robert B.

    1988-01-01

    Presents examples from ancient Greece and Rome illustrating working aged and intergenerational dependence. Describes normal active participation of elderly as officers and common soldiers in ancient military as example of their capabilities. Notes that Alexander the Great's army, in particular, depended on contributions of older men. (Author/NB)

  11. Connect the Book. Always Inventing: A Photobiography of Alexander Graham Bell

    ERIC Educational Resources Information Center

    Brodie, Carolyn S.

    2004-01-01

    Cell phones, video phones, voice messaging?one wonders what Alexander Graham Bell would have thought about the many venues today for electronic communication with one another. Bell's March 10, 1876 invention is now 128 years old, but there is no doubt that Bell's "talking machine" changed the world. This article presents a brief review of the…

  12. Friendly Letters on the Correspondence of Helen Keller, Anne Sullivan, and Alexander Graham Bell.

    ERIC Educational Resources Information Center

    Blatt, Burton

    1985-01-01

    Excerpts from the letters between Alexander Graham Bell and Anne Sullivan and Helen Keller are given to illustrate the educational and personal growth of Helen Keller as well as the educational philosophy of Bell regarding the education of the deaf blind. (DB)

  13. Alexander Cameron Rutherford: A Gentleman and a Scholar. Documents in the Classroom.

    ERIC Educational Resources Information Center

    Hodysh, Henry W.

    2000-01-01

    Provides information about Alexander Cameron Rutherford, a provincial politician. Includes a letter written by Rutherford in 1912 that provides insights into his responsibilities to the general public, information about Rutherford himself, the economic conditions of Alberta, Canada in 1912, and information about the individual to whom it was…

  14. The Doors to Home and History: Post-Colonial Identities in Meena Alexander and Bharati Mukherjee.

    ERIC Educational Resources Information Center

    Dave, Shilpa

    1993-01-01

    Examines postcolonial inquiry and studies of identity in Asians of Indian descent, focusing on the works of Meena Alexander and Bharati Mukherjee. Their commentaries on India and immigrant cultures are constantly influenced by a history dependent on Western tradition, although both authors resist the stereotypical definitions imposed by the West.…

  15. Russia's Literary Genius Alexander Pushkin: The Great-Grandson of an African Slave.

    ERIC Educational Resources Information Center

    Lounsbery, Anne

    2000-01-01

    Alexander Pushkin, Russia's most celebrated literary figure, descended from an African slave. On both parents' sides, he was related to Avram Petrovich Gannibal, who was born to an African prince and abducted to become a slave to a Russian diplomat. Pushkin chose to pride himself on both his aristocratic life and his African ancestry. (SM)

  16. 33 CFR 162.250 - Port Alexander, Alaska; speed of vessels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Port Alexander, Alaska; speed of vessels. 162.250 Section 162.250 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.250...

  17. 76 FR 54800 - Sandy Alexander, Clifton, NJ; Notice of Negative Determination on Reconsideration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Employment and Training Administration Sandy Alexander, Clifton, NJ; Notice of Negative Determination on... resulted in a negative determination based on the findings that the petitioning worker group did not meet... or the law. Conclusion After reconsideration, I affirm the original notice of negative...

  18. Progressive Pioneer: Alexander James Inglis (1879-1924) and American Secondary Education

    ERIC Educational Resources Information Center

    Wraga, William G.

    2006-01-01

    Alexander James Inglis's transformation from an academic traditionalist devoted to Latin pedagogy to an influential progressive-experimentalist and advocate of the comprehensive high school during the early twentieth century has received insufficient attention from educational and curriculum historians. A reconstruction of Inglis's career leads to…

  19. Another View of Dynamic Criteria: A Critical Reanalysis of Barrett, Caldwell, and Alexander.

    ERIC Educational Resources Information Center

    Austin, James T.; And Others

    1989-01-01

    A critical reanalysis of Barrett, Caldwell, and Alexander's (1985) critique of dynamic criteria. Summarizes and questions Barrett, et al.'s three definitions of dynamic criteria and their conclusion that reported temporal changes in criteria could be explained by methodological artifacts. A greater focus on dynamic criteria as constructs is…

  20. The Election of 1800: Alexander Hamilton and the Death of the Federalist Party.

    ERIC Educational Resources Information Center

    Holbrook-DeFeo, Gary

    1993-01-01

    Describes the significance of the election of 1800 in the development of political parties in the United States. Contends that Alexander Hamilton's view of the United States Constitution was dangerous for the new nation and led to a permanent split in the Federalist Party. Includes a resource bibliography for teachers wishing to incorporate this…

  1. Alexander Hamilton: Soldier-Statesmen of the Constitution. A Bicentennial Series No. 16.

    ERIC Educational Resources Information Center

    Army Center of Military History, Washington, DC.

    Alexander Hamilton was among the most intellectually gifted of the Founding Fathers and a brilliant political theorist, but he lacked practical political experience, and his major political contributions occurred only when his specific policies were adopted and carried forward by others with broader vision. This booklet on Hamilton is one in a…

  2. What Matters to Alexander Astin? A Conversation with Higher Education's Senior Scholar

    ERIC Educational Resources Information Center

    About Campus, 2003

    2003-01-01

    Since the mid-1960s, the work of Alexander Astin--Allan M. Cartter Professor of Higher Education at the University of California-Los Angeles and director of the Higher Education Research Institute--has served as both bellwether for and mirror of the American college and university system. He was there to study and shed light on the student…

  3. The effect of Alexander technique training program: A qualitative study of ordinary behavior application

    PubMed Central

    Kim, Soo-Yeon; Baek, Soon Gi

    2014-01-01

    The purpose of this study was to configure and apply the Alexander technique training program and assess the effect of program through physical, emotional and behavioral aspects. To achieve the research aims, qualitative research method had been conducted, subjecting 8 people, who were participating in Alexander Technique training program for this study. The study used focus group interview method for collecting date and employed for the interview method by mixing the semi-structured and unstructured questionnaire. The results were followings. First, one could develop body awareness and body consciousness through experiencing lived bodily sensation. Second, from Alexander Technique training program, people experienced psycho & physical’s equilibrium. Third, one could change not only the manner of use of body but also the attitude to the life from conscious attention to daily ordinary movement. The results provided empirical evidence of Alexander Technique training program’s functions in terms of physical, emotional and behavioral aspect through the process of consciousness control from lived body education. PMID:25610819

  4. Holocene morphogenesis of Alexander the Great's isthmus at Tyre in Lebanon

    PubMed Central

    Marriner, Nick; Morhange, Christophe; Meulé, Samuel

    2007-01-01

    In 332 B.C., Alexander the Great constructed an ≈1,000-m-long causeway to seize the offshore island of Tyre. The logistics behind this engineering feat have long troubled archaeologists. Using the Holocene sedimentary record, we demonstrate that Alexander's engineers cleverly exploited a shallow proto-tombolo, or sublittoral sand spit, to breach the offshore city's defensive impregnability. We elucidate a three-phase geomorphological model for the spit's evolution. Settled since the Bronze Age, the area's geological record manifests a long history of natural and anthropogenic forcings. (i) Leeward of the island breakwater, the maximum flooding surface (e.g., drowning of the subaerial land surfaces by seawater) is dated ≈8000 B.P. Fine-grained sediments and brackish and marine-lagoonal faunas translate shallow, low-energy water bodies at this time. Shelter was afforded by Tyre's elongated sandstone reefs, which acted as a 6-km natural breakwater. (ii) By 6000 B.P., sea-level rise had reduced the dimensions of the island from 6 to 4 km. The leeward wave shadow generated by this island, allied with high sediment supply after 3000 B.P., culminated in a natural wave-dominated proto-tombolo within 1–2 m of mean sea level by the time of Alexander the Great (4th century B.C.). (iii) After 332 B.C., construction of Alexander's causeway entrained a complete anthropogenic metamorphosis of the Tyrian coastal system. PMID:17517668

  5. Identification of metapopulation dynamics among Northern Goshawks of the Alexander Archipelago, Alaska, and Coastal British Columbia

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; McClaren, Erica L.; Doyle, Frank I.; Titus, K.; Sage, George K.; Wilson, Robert E.; Gust, Judy R.; Talbot, Sandra L.

    2012-01-01

    Northern Goshawks occupying the Alexander Archipelago, Alaska, and coastal British Columbia nest primarily in old-growth and mature forest, which results in spatial heterogeneity in the distribution of individuals across the landscape. We used microsatellite and mitochondrial data to infer genetic structure, gene flow, and fluctuations in population demography through evolutionary time. Patterns in the genetic signatures were used to assess predictions associated with the three population models: panmixia, metapopulation, and isolated populations. Population genetic structure was observed along with asymmetry in gene flow estimates that changed directionality at different temporal scales, consistent with metapopulation model predictions. Therefore, Northern Goshawk assemblages located in the Alexander Archipelago and coastal British Columbia interact through a metapopulation framework, though they may not fit the classic model of a metapopulation. Long-term population sources (coastal mainland British Columbia) and sinks (Revillagigedo and Vancouver islands) were identified. However, there was no trend through evolutionary time in the directionality of dispersal among the remaining assemblages, suggestive of a rescue-effect dynamic. Admiralty, Douglas, and Chichagof island complex appears to be an evolutionarily recent source population in the Alexander Archipelago. In addition, Kupreanof island complex and Kispiox Forest District populations have high dispersal rates to populations in close geographic proximity and potentially serve as local source populations. Metapopulation dynamics occurring in the Alexander Archipelago and coastal British Columbia by Northern Goshawks highlight the importance of both occupied and unoccupied habitats to long-term population persistence of goshawks in this region.

  6. The Language of Teaching Coordination: Suzuki Training Meets the Alexander Technique.

    ERIC Educational Resources Information Center

    Madden, Catherine

    2002-01-01

    Details an investigation of the language of Suzuki instruction and the students' interpretation of that language. Describes the Alexander Technique and Suzuki training and provides specific examples illustrating the interaction of language and coordination in this context. Proposes that teachers of movement, voice and acting can benefit from these…

  7. A Disciplinary Immigrant. Alexander Smith at the University of Chicago, 1894-1911

    ERIC Educational Resources Information Center

    Cotter, Donald

    2008-01-01

    The publication in 1906 of Alexander Smith's "Introduction to general inorganic chemistry" inaugurated a decisive change in chemical pedagogy in the US, the effects of which are still evident. The nature and extent of Smith's innovations are described through a comparison of his text to its source material and contemporaries. His…

  8. John von Neumann Birthday Centennial

    SciTech Connect

    Grcar, Joseph F.

    2004-11-12

    In celebration of John von Neumann's 100th birthday, a series of four lectures were presented on the evening of February 10, 2003 during the SIAM Conference on Computational Science and Engineering in San Diego. The venue was appropriate because von Neumann spent much of the later part of his life, in the 1950's, as an unofficial ambassador for computational science. He was then the only senior American scientist who had experience with the new computers (digital, electronic, and programmable) and a vision of their future importance. No doubt he would have relished the chance to attend a meeting such as this. The first speaker, William Aspray, described the ''interesting times'' during which computers were invented. His remarks were based on his history [1] of this period in von Neumann's life. We were honored to have John von Neumann's daughter, Marina von Neumann-Whitman, as our second speaker. Other accounts of von Neumann's life can be found in books by two of his colleagues [2] and [3]. Our third speaker, Peter Lax, provided both mathematical and international perspectives on John von Neumann's career. Finally, Pete Stewart spoke about von Neumann's numerical error analysis [4] in the context of later work; this talk did not lend itself to transcription, but readers may consult the historical notes in [5]. Our thanks to all the speakers for a remarkable evening. We are grateful to the DOE Applied Mathematical Sciences (AMS) program for partially supporting these lectures. Thanks are also due to SIAM and William Kolata, to our emcee, Gene Golub, to Paul Saylor for recording and editing, and to Barbara Lytle for the transcriptions. More about von Neumann's work can be learned from the recent American Mathematical Society proceedings [6].

  9. Von Hippel's disease in association with von Recklinghausen's neurofibromatosis.

    PubMed Central

    Thomas, J V; Schwartz, P L; Gragoudas, E S

    1978-01-01

    Ten members of a large family who showed manifestations of either von Hippel-Lindau disease or von Recklinghausen's neurofibromatosis were examined. Three of 10 members were found to have retinal angiomas which had not been present on fundus examination 3 years previously. These angiomas were associated with ocular and systemic signs of neurofibromatosis. These cases show overlapping manifestations of different phakomatoses and provide support for the concept of a common aetiology for these diseases. Images PMID:101230

  10. von Braun and German Publisher

    NASA Technical Reports Server (NTRS)

    1969-01-01

    In this photograph, Guenter Ogger of Capitol Magazine, West Germany, greets Marshall Space Flight Center Director, Dr. Wernher von Braun. Mr. Ogger interviewed the famous rocket scientist for his magazine.

  11. Von Karman and JATO Team

    NASA Technical Reports Server (NTRS)

    1940-01-01

    Dr. Theodore von Karman (black coat) sketches out a plan on the wing of an airplane as his JATO engineering team looks on. From left to right: Dr. Clark B. Millikan, Dr.Martin Summerfield, Dr. Theodore von Karman, Dr. Frank J. Malina and pilot, Capt. Homer Boushey. Captain Boushey would become the first American to pilot an airplane that used JATO (Jet Assisted Take-Off) solid propellent rockets.

  12. The Use of "Ability" Measures as Controls for Concurrent or Subsequent Achievement (Comment on Alexander et al., ASR, October 1981).

    ERIC Educational Resources Information Center

    Coleman, James S.

    1982-01-01

    Comments upon a 1981 article by Alexander, Pallas, and Cook. Discusses whether particular standardized tests measure achievement or ability and the implications of this issue for school effects research. (GC)

  13. Protein misfolding and oxidative stress promote glial-mediated neurodegeneration in an Alexander disease model

    PubMed Central

    Wang, Liqun; Colodner, Kenneth J.; Feany, Mel B.

    2011-01-01

    Although alterations in glial structure and function commonly accompany death of neurons in neurodegenerative diseases, the role glia play in modulating neuronal loss is poorly understood. We have created a model of Alexander disease in Drosophila by expressing disease-linked mutant versions of glial fibrillary acidic protein (GFAP) in fly glia. We find aggregation of mutant human GFAP into inclusions bearing the hallmarks of authentic Rosenthal fibers. We also observe significant toxicity of mutant human GFAP to glia, which is mediated by protein aggregation and oxidative stress. Both protein aggregation and oxidative stress contribute to activation of a robust autophagic response in glia. Toxicity of mutant GFAP to glial cells induces a non-cell autonomous stress response and subsequent apoptosis in neurons, which is dependent on glial glutamate transport. Our findings thus establish a simple genetic model of Alexander disease and further identify cellular pathways critical for glial-induced neurodegeneration. PMID:21414908

  14. Paleozoic paleomagnetism and northward drift of the Alexander Terrane, southeastern Alaska

    NASA Astrophysics Data System (ADS)

    van Der Voo, Rob; Jones, Meridee; Gromme, C. Sherman; Eberlein, G. Donald; Churkin, Michael, Jr.

    1980-10-01

    Paleozoic limestone, graywacke, sandstone, milestone, red beds and volcanic rocks of the Alexander terrane, southeastern Alaska, have yielded six paleomagnetic pole positions after thermal and alternating-field demagnetization. These poles are from sample groups of late Middle Ordovician, Late Ordovician, Devonian, Late Devonian, and early and late Carboniferous age. To test various tectonic models for the structural development of this part of western North America, the paleomagnetic results are compared to those for the North American craton. It is found that the observed inclination and declination values deviate significantly from the values predicted for the present-day position of the Alexander terrane (55.5N, 133.5W). Better matching can be obtained for a paleoposition of the terrane at about 40N, 120W, in the present position of western Nevada and northeastern California. In addition, an in situ 25° clockwise rotation of the terrane is required to restore it to its original position.

  15. Pennsylvanian pluton stitching of Wrangellia and the Alexander terrane, Wrangell Mountains, Alaska

    SciTech Connect

    Gardner, M.C.; Bergman, S.C.; Cushing, G.W. ); Plafker, G. ); Campbell, R.B.; Dodds, C.J. ); McClelland, W.C. ); Mueller, P.A. ); MacKevett, E.M. Jr.

    1988-11-01

    A quartz monzonite-syenite-alkali granite plutonic complex in eastern Alaska crosscuts the contact of the Alexander terrane and Wrangellia and intrudes the basement rocks of both terranes. Zircon U-Pb data indicate an intrusion age of 309 {plus minus} 5 Ma (Middle Pennsylvanian) for the pluton, and {sup 40}K-{sup 40}Ar age for hornblende separates indicate cooling to about 450 C during Middle Pennsylvanian-Early Permian time. The new field relations and age data demonstrate the Wrangellia and the Alexander terrane were contiguous during the Middle Pennsylvanian. This conclusion provides an important new constraint on paleogeographic reconstructions of the northwest Cordillera, and necessitates reassessment of stratigraphic and paleomagnetic data that were cited as evidence that the terranes evolved separately until the late Mesozoic.

  16. Clinical Experience in Late Antiquity: Alexander of Tralles and the Therapy of Epilepsy

    PubMed Central

    Bouras-vallianatos, Petros

    2014-01-01

    Alexander of Tralles, writing in the late sixth century, combined his wide-ranging practical knowledge with earlier medical theories. This article shows how clinical experience is used in Alexander’s works by concentrating on his therapeutic advice on epilepsy and, in particular, on pharmacology and the group of so-called natural remedies. I argue that clinical testing is used not only for the introduction of new medicines but also as an instrument for checking the therapeutic effect of popular healing practices. On another level, this article discusses Alexander’s role as the author of a medical compendium; it suggests that by marking the cases of clinical testing with a set of recurrent expressions, Alexander leads his audience to reflect on his medical authority and personal contribution. PMID:25045178

  17. Scaphopoda from the Alexander Terrane, Southeast Alaska-The first occurrence of Scaphopoda in the Silurian

    USGS Publications Warehouse

    Rohr, D.M.; Blodgett, R.B.; Baichtal, J.

    2006-01-01

    The scaphopods Dentalium hecetaensis n. sp. and Rhytiodentalium cf. kentuckyensis Pojeta et Runnegar, 1979, are described from Ludlow-age strata of the Heceta Limestone on Prince of Wales Island, Southeast Alaska. This is the first occurrence of Silurian scaphopods known to date. They are part of a diverse macrobenthic fauna of the Alexander terrane, an accreted southern Alaskan terrane of Siberian or Uralian affinities. ?? 2006 Nanjing Institute of Geology and Palaeontology, CAS.

  18. PLC/PRF/5 (Alexander) hepatoma cell line: further characterization and studies of infectivity.

    PubMed Central

    Daemer, R J; Feinstone, S M; Alexander, J J; Tully, J G; London, W T; Wong, D C; Purcell, R H

    1980-01-01

    The Alexander hepatoma cell line, PLC/PRF/5, was studied for evidence of hepatitis B virus markers and alpha-fetoprotein. Only hepatitis B surface antigen and alpha-fetoprotein were detected. Induction experiments with 5-iodo-2'-deoxyuridine and inoculation of chimpanzees with whole cells or tissue culture fluid did not reveal evidence of synthesis of additional hepatitis B virus markers or of production of infectious virus. Images Fig. 1 Fig. 2 Fig. 3 PMID:6160110

  19. Lithium Decreases Glial Fibrillary Acidic Protein in a Mouse Model of Alexander Disease.

    PubMed

    LaPash Daniels, Christine M; Paffenroth, Elizabeth; Austin, Elizabeth V; Glebov, Konstantin; Lewis, Diana; Walter, Jochen; Messing, Albee

    2015-01-01

    Alexander disease is a fatal neurodegenerative disease caused by mutations in the astrocyte intermediate filament glial fibrillary acidic protein (GFAP). The disease is characterized by elevated levels of GFAP and the formation of protein aggregates, known as Rosenthal fibers, within astrocytes. Lithium has previously been shown to decrease protein aggregates by increasing the autophagy pathway for protein degradation. In addition, lithium has also been reported to decrease activation of the transcription factor STAT3, which is a regulator of GFAP transcription and astrogliogenesis. Here we tested whether lithium treatment would decrease levels of GFAP in a mouse model of Alexander disease. Mice with the Gfap-R236H point mutation were fed lithium food pellets for 4 to 8 weeks. Four weeks of treatment with LiCl at 0.5% in food pellets decreased GFAP protein and transcripts in several brain regions, although with mild side effects and some mortality. Extending the duration of treatment to 8 weeks resulted in higher mortality, and again with a decrease in GFAP in the surviving animals. Indicators of autophagy, such as LC3, were not increased, suggesting that lithium may decrease levels of GFAP through other pathways. Lithium reduced the levels of phosphorylated STAT3, suggesting this as one pathway mediating the effects on GFAP. In conclusion, lithium has the potential to decrease GFAP levels in Alexander disease, but with a narrow therapeutic window separating efficacy and toxicity.

  20. Von Willebrand factor processing.

    PubMed

    Brehm, Maria A

    2017-01-31

    Von Willebrand factor (VWF) is a multimeric glycoprotein essential for primary haemostasis that is produced only in endothelial cells and megakaryocytes. Key to VWF's function in recruitment of platelets to the site of vascular injury is its multimeric structure. The individual steps of VWF multimer biosynthesis rely on distinct posttranslational modifications at specific pH conditions, which are realized by spatial separation of the involved processes to different cell organelles. Production of multimers starts with translocation and modification of the VWF prepropolypeptide in the endoplasmic reticulum to produce dimers primed for glycosylation. In the Golgi apparatus they are further processed to multimers that carry more than 300 complex glycan structures functionalized by sialylation, sulfation and blood group determinants. Of special importance is the sequential formation of disulfide bonds with different functions in structural support of VWF multimers, which are packaged, stored and further processed after secretion. Here, all these processes are being reviewed in detail including background information on the occurring biochemical reactions.

  1. Richard von Volkmann

    PubMed Central

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R.

    2008-01-01

    Richard von Volkmann (1830–1889), one of the most important surgeons of the 19th century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867–1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the “antiseptic technique” to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann’s contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children’s fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics. PMID:18196438

  2. Teachers' professional development needs and current practices at the Alexander Science Center School

    NASA Astrophysics Data System (ADS)

    Gargus, Gerald Vincent

    This investigation represents an in-depth understanding of teacher professional development at the Alexander Science Center School, a dependent charter museum school established through a partnership between the California Science Center and Los Angeles Unified School District. Three methods of data collection were used. A survey was distributed and collected from the school's teachers, resulting in a prioritized list of teacher professional development needs, as well as a summary of teachers' opinions about the school's existing professional development program. In addition, six key stakeholders in the school's professional development program were interviewed for the study. Finally, documents related to the school's professional development program were analyzed. Data collected from the interviews and documents were used to develop an understand various components of the Alexander Science Center School's professional development program. Teachers identified seven areas that had a high-priority for future professional development including developing skills far working with below-grade-level students, improving the analytical skills of student in mathematics, working with English Language Learners, improving students' overall reading ability levels, developing teachers' content-area knowledge for science, integrating science across the curriculum, and incorporating hands-on activity-based learning strategies to teach science. Professional development needs identified by Alexander Science Center School teachers were categorized based on their focus on content knowledge, pedagogical content knowledge, or curricular knowledge. Analysis of data collected through interviews and documents revealed that the Alexander Science Center School's professional development program consisted of six venues for providing professional development for teachers including weekly "banked time" sessions taking place within the standard school day, grade-level meetings, teacher support

  3. Origin of Silurian reefs in the Alexander Terrane of southeastern Alaska

    SciTech Connect

    Soja, C.M. )

    1991-04-01

    Lower to Upper Silurian (upper Llandovery-Ludlow) limestones belonging to the Heceta Formation record several episodes of reef growth in the Alexander terrane of southeastern Alaska. As the oldest carbonates of wide-spread distribution in the region, the Heceta limestones represent the earliest development of a shallow-marine platform within the Alexander arc and the oldest foundation for reef evolution. These deposits provide important insights into the dynamic processes, styles, and bathymetry associated with reef growth in tectonically active oceanic islands. Massive stromatoporoids, corals, and red algae are preserved in fragmental rudstones and represent a fringing reef that formed at the seaward edge of the incipient marine shelf. Accessory constituents in this reef include crinoids and the cyanobacterium Girvanella. Small biostromes were constructed by ramose corals and stromatoporoids on oncolitic substrates in backreef or lagoonal environments. These buildups were associated with low-diversity assemblages of brachiopods and with gastropods, amphiporids, calcareous algae and cyanobacteria. Microbial boundstones reflect the widespread encrustation of cyanobacteria and calcified microproblematica on shelly debris as stromatolitic mats that resulted in the development of a stromatactoid-bearing mud mound and a barrier reef complex. Epiphytaceans, other microbes, and aphrosalpingid sponges were the primary frame-builders of the barrier reefs. These buildups attained significant relief at the shelf margin and shed detritus as slumped blocks and debris flows into deep-water sites along the slope. The similarity of these stromatolitic-aphrosalpingid reefs to those from Siluro-Devonian strata of autochthonous southwestern Alaska suggests paleobiogeographic ties of the Alexander terrane to cratonal North America during the Silurian.

  4. The remarkable medical lineage of the Monro family: contributions of Alexander primus, secundus, and tertius.

    PubMed

    Wu, Osmond C; Manjila, Sunil; Malakooti, Nima; Cohen, Alan R

    2012-06-01

    Among the families that have influenced the development of modern medicine into what it is today, the Monro lineage stands as one of the most notable. Alexander Monro primus (1697-1767) was the first of 3 generations with the same name, a dynasty that spanned 126 years occupying the Chair of Anatomy one after the other at the University of Edinburgh. After becoming Professor of Anatomy at the University of Edinburgh in 1719, Monro primus played a principal role in the establishment of the University of Edinburgh School of Medicine and the Edinburgh Royal Infirmary. In 1726, he published The Anatomy of the Humane Bones, of which 8 editions were printed during his lifetime. His son, Alexander Monro secundus (1733-1817), arguably the most notable of the 3 men, succeeded him as Professor of Anatomy. A highly regarded lecturer and anatomist, Monro secundus studied under many great physicians, including William Hunter and Johann Friedrich Meckel the Elder, and was also teacher to other well-known figures at the time, such as Joseph Black and Thomas Trotter. His most notable contributions include his work with the lymphatic system, the interventricular foramen (of Monro), and the Monro-Kellie doctrine. Alexander Monro tertius (1773-1859), the last of the dynasty, also succeeded his father as Professor of Anatomy. His work included insights into abdominal aortic aneurysms and the anatomy of the genitourinary system. The prominent association of the Monro family with the University of Edinburgh and the effects of a tenured professorship under the concept of "Ad vitam aut culpam" over successive generations are also described. To the best of the authors' knowledge, this historical review of the Monro family is among the few published in neurosurgical literature. A vivid historical overview of the medical contributions of the most famous and influential dynasty of physicians in Edinburgh at that time is provided, with relevant excerpts from original publications.

  5. Alexander the Great: A Strategy Review in the Context of the ACSC strategy Process Model

    DTIC Science & Technology

    1984-03-01

    observe the development of both political and military strategies in support of a specific national objective. As ruler of Greece and later of a massive...was born in 356 B.C. in Macedonia (the northern part of modern Greece ), the son of Philip II, the king of Macedonia. At the age of 16 Alexander...left wing of his father’s army at the dec ive battle of Chaeronea in which Philip defeated the allied Greek forces 1 won control of Greece . Philip

  6. Familial Adult-onset Alexander Disease: Clinical and Neuroradiological Findings of Three Cases

    PubMed Central

    ELMALI, Ayşe Deniz; ÇETİNÇELİK, Ümran; IŞLAK, Civan; UZUN ADATEPE, Nurten; KARAALİ SAVRUN, Feray; YALÇINKAYA, Cengiz

    2016-01-01

    The adult-onset Alexander disease (AOAD) dramatically differs from the early onset AD with respect to clinical and neuroradiological findings. Herein we report the detailed clinical and neuroradiological findings of a Turkish family with AOAD. In all three cases, magnetic resonance imaging revealed marked atrophy of the mesencephalon, bulbus, and cervical spinal cord accompanied with signal abnormalities in the same regions along with supratentorial white matter. Basal ganglia were affected in two cases. Molecular genetic analysis revealed heterozygous mutation in the 8th exon of the glial fibrillary acidic protein gene M451I (c.1245G>A), leading to the diagnosis of AOAD in all cases. PMID:28360791

  7. Von Hippel-Lindau Disease

    MedlinePlus

    Von Hippel-Lindau disease (VHL) is a rare, genetic disease that causes tumors and cysts to grow in your body. The tumors can be either ... and, in men, their genital tract. Symptoms of VHL vary and depend on the size and location ...

  8. The ocular motor features of adult-onset alexander disease: a case and review of the literature.

    PubMed

    Pfeffer, Gerald; Abegg, Mathias; Vertinsky, A Talia; Ceccherini, Isabella; Caroli, Francesco; Barton, Jason J S

    2011-06-01

    A 51-year-old Chinese man presented with gaze-evoked nystagmus, impaired smooth pursuit and vestibular ocular reflex cancellation, and saccadic dysmetria, along with a family history suggestive of late-onset autosomal dominant parkinsonism. MRI revealed abnormalities of the medulla and cervical spinal cord typical of adult-onset Alexander disease, and genetic testing showed homozygosity for the p.D295N polymorphic allele in the gene encoding the glial fibrillary acidic protein. A review of the literature shows that ocular signs are frequent in adult-onset Alexander disease, most commonly gaze-evoked nystagmus, pendular nystagmus, and/or oculopalatal myoclonus, and less commonly ptosis, miosis, and saccadic dysmetria. These signs are consistent with the propensity of adult-onset Alexander disease to cause medullary abnormalities on neuroimaging.

  9. Trace element analysis of Alexander the Great's silver tetradrachms minted in Macedonia

    NASA Astrophysics Data System (ADS)

    Kallithrakas-Kontos, N.; Katsanos, A. A.; Touratsoglou, J.

    2000-11-01

    The coinage of Alexander the Great presents a special interest because of its international character in the frame of the ancient times. At least 31 mints (from Aigai to Babylon and from Pella to Alexandreia) operated in the vast state, which was created by Alexander in just over 10 years (334-323 BC). Impressive quantities of tetradrachms were consequently minted for the economic affairs of an expanding state. The mints continued to be active and after the premature death of the Macedonian king, producing among others and tetradrachms in his name. The elemental chemical composition of silver tetradrachms minted in Amphipolis as well as in other Macedonian Greek cities was analysed by energy dispersive X-ray fluorescence (EDXRF), and 12 elements were determined. The problem of the patina (silver corrosion layer) effects on the results was examined by analysis before and after the corrosion product removal. From the results of the chemical composition, a similar numismatic policy is deduced for all the analysed coin as well as metal provenance indications for some of the coins.

  10. Possible refugia in the Alexander Archipelago of southeastern Alaska during the late Wisconsin glaciation

    USGS Publications Warehouse

    Carrara, P.E.; Ager, T.A.; Baichtal, J.F.

    2007-01-01

    The interpretation of the extent of late Wisconsin glaciation in southeastern Alaska has varied between geologists and biologists. Maps and reports of the region prepared by geologists commonly indicated that late Wisconsin ice extended as a large uniform front west to the edge of the continental shelf. However, the distribution of plants and animals in the region has led many biologists to suggest that there may have been ice-free areas that served as refugia during the late Wisconsin. Based on analyses of aerial photographs, topographic maps, and bathymetric charts, in conjunction with a review of previous literature and reconnaissance fieldwork throughout the region, this study presents data supporting a limited ice extent in the Alexander Archipelago during the late Wisconsin and identifies possible ice-free areas that may have served as refugia. These areas include (1) the Fairweather Ground, (2) the Herbert Graves Island area, (3) the western coast of southern Baranof Island and adjacent continental shelf, (4) Coronation Island and the adjacent continental shelf, (5) the Warren Island area, (6) the continental shelf from west of Heceta Island to Forrester Island in the south, (7) parts of the west coast of southern Dall Island, and (8) lowland areas in southern Prince of Wales Island. The identification of these possible refugia has bearing on the recolonization of the Alexander Archipelago, as they could have served as centers of biotic dispersal upon regional deglaciation and as stepping stones for early humans with a maritime tradition entering the western hemisphere from Asia. ?? 2007 NRC Canada.

  11. Geohydrology and water-chemistry of the Alexander Valley, Sonoma County, California

    USGS Publications Warehouse

    Metzger, Loren F.; Farrar, Christopher D.; Koczot, Kathryn M.; Reichard, Eric G.

    2006-01-01

    This study of the geohydrology and water chemistry of the Alexander Valley, California, was done to provide an improved scientific basis for addressing emerging water-management issues, including potential increases in water demand and changes in flows in the Russian River. The study tasks included (1) evaluation of existing geohydrological, geophysical, and geochemical data; (2) collection and analysis of new geohydrologic data, including subsurface lithologic data, ground-water levels, and streamflow records; and (3) collection and analysis of new water-chemistry data. The estimated total water use for the Alexander Valley for 1999 was approximately 15,800 acre-feet. About 13,500 acre-feet of this amount was for agricultural use, primarily vineyards, and about 2,300 acre-feet was for municipal/industrial use. Ground water is the main source of water supply for this area. The main sources of ground water in the Alexander Valley are the Quaternary alluvial deposits, the Glen Ellen Formation, and the Sonoma Volcanics. The alluvial units, where sufficiently thick and saturated, comprise the best aquifer in the study area. Average recharge to the Alexander Valley is estimated from a simple, basinwide water budget. On the basis of an estimated annual average of 298,000 acre-feet of precipitation, 160,000 acre-feet of runoff, and 113,000 to 133,000 acre-feet of evapotranspiration, about 5,000 to 25,000 acre-feet per year is available for ground-water recharge. Because this estimate is based on differences between large numbers, there is significant uncertainty in this recharge estimate. Long-term changes in ground-water levels are evident in parts of the study area, but because of the sparse network and lack of data on well construction and lithology, it is uncertain if any significant changes have occurred in the northern part of the study area since 1980. In the southern half of the study area, ground-water levels generally were lower at the end of the 2002 irrigation

  12. [Was Klaus von Mantrei the teacher of Hans von Gersdorff?].

    PubMed

    Vollmuth, R

    1996-01-01

    One of the most popular representatives of surgery at the end of the middle ages and the beginning modern era is the Strassburgian surgeon Hans von Gersdorff. Still we do not know very much about his life and his surgical teachers. Only one meister Nicklaus, called Mulartzt, is mentioned as such by the remarks in Gersdorffs 'Feldbuch der Wundarznei', but till today this surgeon could not be identified in more detail. This article now holds the thesis, that meister Nicklaus is probably identical with Klaus von Matrei (Metry), a well-known surgeon of the late 15th century. That cannot be fully proved yet, but a number of coinciding characteristics between the two and some further indications, that are explained, seem so significant, that the thesis can hardly be doubted.

  13. Treatment of von Willebrand Disease.

    PubMed

    Curnow, Jennifer; Pasalic, Leonardo; Favaloro, Emmanuel J

    2016-03-01

    Congenital von Willebrand disease (VWD) and acquired von Willebrand syndrome (AVWS) reflect conditions caused by von Willebrand factor (VWF) deficiency and/or defects. VWD is the most common inherited bleeding disorder and AVWS arises from a variety of causes. Since VWF stabilizes and protects factor VIII (FVIII) in the circulation, this is also reduced in many patients with VWD. The treatment of VWD and AVWS therefore primarily entails replacement of VWF, and sometimes FVIII, to protect against bleeding. This may entail the use of VWF concentrates (currently plasma-derived) and/or FVIII concentrates (currently plasma-derived or more increasingly recombinant forms), and/or desmopressin to release endogenous VWF in subgroups of patients. For AVWS additional treatment of the underlying condition is also required. Adjunct therapies include antifibrinolytics. Globally, various formulations exist for both VWF and FVIII concentrates and are differentially available based on manufacturer marketing or regulatory approvals/clearances in different geographies. Also, guidelines for treatment of VWD vary for different localities and recombinant VWF is undergoing clinical trials. The current review provides an overview of the treatment of VWD as currently practiced in developed countries, and also provides a glimpse towards the future.

  14. Dr. von Braun Briefing Walt Disney

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Dr. von Braun began his association with Walt Disney in the 1950s when the rocket scientist appeared in three Disney television productions related to the exploration of space. Years later, Dr. von Braun invited Disney and his associates to tour the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This photograph is dated April 13, 1965. From left are R.J. Schwinghamer from the MSFC, Disney, B.J. Bernight, and Dr. von Braun.

  15. Speciation despite globally overlapping distributions in Penicillium chrysogenum: the population genetics of Alexander Fleming’s lucky fungus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eighty years ago, Alexander Fleming described the antibiotic effects of a fungus that had contaminated his bacterial culture, kick starting the antimicrobial revolution. The fungus was later ascribed to a globally distributed asexual species, Penicillium chrysogenum. Recently, the species has been...

  16. Mythorealistic Concept of "Beautiful Lady" in the Structure of the Author's Identity (Based on the Diaries of Alexander Blok)

    ERIC Educational Resources Information Center

    Minets, Diana

    2016-01-01

    The present paper deals with the diaries of Alexander Blok dated 1901-1921 reflecting the process of the writer's self-identification. During 20 years under the influence of various social and cultural situations Blok's "Self-Conception" is undergoing significant changes. The vector of these changes shows the complicated evolution of the…

  17. Growing Community: The Impact of the Stephanie Alexander Kitchen Garden Program on the Social and Learning Environment in Primary Schools

    ERIC Educational Resources Information Center

    Block, Karen; Gibbs, Lisa; Staiger, Petra K.; Gold, Lisa; Johnson, Britt; Macfarlane, Susie; Long, Caroline; Townsend, Mardie

    2012-01-01

    This article presents results from a mixed-method evaluation of a structured cooking and gardening program in Australian primary schools, focusing on program impacts on the social and learning environment of the school. In particular, we address the Stephanie Alexander Kitchen Garden Program objective of providing a pleasurable experience that has…

  18. The Four Domains of Moral Education: The Contributions of Dewey, Alexander and Goleman to a Comprehensive Taxonomy.

    ERIC Educational Resources Information Center

    Zigler, Ronald Lee

    1998-01-01

    Attempts to place a neglected dimension of John Dewey's work into its proper context. Examines the works of Dewey, F. Matthias Alexander, and Daniel Goldman to create four domains that must be addressed by a truly comprehensive model of moral education: direct external, indirect external, direct internal, and indirect internal. (DSK)

  19. History of quantum electronics at the Moscow Lebedev and General Physics Institutes: Nikolaj Basov and Alexander Prokhorov.

    PubMed

    Karlov, N V; Krokhin, O N; Lukishova, S G

    2010-09-01

    Some moments of maser and laser history in the Soviet Union are outlined, commemorating the work of Nikolaj G. Basov and Alexander M. Prokhorov, who, together with Charles H. Townes, were awarded the 1964 Nobel Prize "for fundamental work in the field of quantum electronics, which has led to the construction of oscillators and amplifiers based on the maser-laser principle."

  20. Nichtlineare Rauschmodellierung von LC Tank VCOs

    NASA Astrophysics Data System (ADS)

    Thiessen, T.; Bremer, J.-K.; Mathis, W.

    2008-05-01

    Im Rahmen dieser Arbeit wird ein alternativer Ansatz zur Phasenrauschoptimierung von LC-Tank Oszillatoren (VCOs) unter Verwendung stochastischer Differentialgleichungen vorgestellt. Zunächst werden die linearen Ansätze von Leeson, Hajimiri und Lee analysiert und bewertet. Danach wird ein Konzept vorgestellt, mit dem man die Rauscheigenschaften von VCOs auf der Grundlage stochastischer Differentialgleichungen und Fokker-Planck-Gleichungen untersuchen kann. Ziel dieser Arbeit ist eine Beschreibung des Phasenrauschens auf der Basis einer nichtlinearen Rauschmodellierung, welche Parameter eines VCOs für eine Optimierung beinhaltet. Es wurde ein Matlab-Tool erstellt und die Funktionalität anhand von Simulationen verifiziert.

  1. Alexander Gordon, puerperal sepsis, and modern theories of infection control--Semmelweis in perspective.

    PubMed

    Gould, Ian M

    2010-04-01

    Ignaz Semmelweis, a Hungarian doctor who practised in 19th century Vienna, is widely believed to be the father of modern infection control. He earned this accolade when he showed that puerperal sepsis was contagious and that it could be prevented with adequate hand hygiene. In fact, such ideas had circulated in the medical world for at least a century before Semmelweis' work. Moreover, it is well documented that Alexander Gordon, an obstetrician working in Aberdeen, UK, was the first to prove the contagious nature of puerperal sepsis. He also advocated the need for good hygiene for its prevention in a thesis published in 1795. This work described an epidemic of puerperal sepsis that began in Aberdeen in 1789. Gordon's thesis was reprinted three times in Edinburgh, Philadelphia, and London over the next 55 years, suggesting that Semmelweis (1847) could well have known of his work. Like Semmelweis, Gordon was persecuted for his findings.

  2. Finding revelation in anthropology: Alexander Winchell, William Robertson Smith and the heretical imperative.

    PubMed

    Livingstone, David N

    2015-09-01

    Anthropological inquiry has often been considered an agent of intellectual secularization. Not least is this so in the sphere of religion, where anthropological accounts have often been taken to represent the triumph of naturalism. This metanarrative, however, fails to recognize that naturalistic explanations could sometimes be espoused for religious purposes and in defence of confessional creeds. This essay examines two late nineteenth-century figures--Alexander Winchell in the United States and William Robertson Smith in Britain--who found in anthropological analysis resources to bolster rather than undermine faith. In both cases these individuals found themselves on the receiving end of ecclesiastical censure and were dismissed from their positions at church-governed institutions. But their motivation was to vindicate divine revelation, in Winchell's case from the physical anthropology of human origins and in Smith's from the cultural anthropology of Semitic ritual.

  3. Neuromusicology or Musiconeurology? “Omni-art” in Alexander Scriabin as a Fount of Ideas

    PubMed Central

    Triarhou, Lazaros C.

    2016-01-01

    Science can uncover neural mechanisms by looking at the work of artists. The ingenuity of a titan of classical music, the Russian composer Alexander Scriabin (1872–1915), in combining all the sensory modalities into a polyphony of aesthetical experience, and his creation of a chord based on fourths rather than the conventional thirds are proposed as putative points of departure for insight, in future studies, into the neural processes that underlie the perception of beauty, individually or universally. Scriabin’s “Omni-art” was a new synthesis of music, philosophy and religion, and a new aesthetic language, a unification of music, vision, olfaction, drama, poetry, dance, image, and conceptualization, all governed by logic, in the quest for the integrative action of the human mind toward a “higher reality” of which music is only a component. PMID:27014167

  4. Bryan Coast, English Coast, Alexander Island, Fallieres Coast, and Bellingshausen Sea, Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image of Antarctica shows the Bryan Coast (lower left), the English Coast (lower central), Alexander Island (middle right), the Fallieres Coast (top right), and the Bellingshausen Sea. The entire continent has been dedicated to peaceful scientific investigation since 1961, with the signing of the Antarctic Treaty.The waters surrounding Antarctica are intensely cold. Salt water freezes at -2C, allowing sea ice to form. The middle left portion of the image shows quite a lot of sea ice in the Bellingshausen Sea. During the Antarctic winter, when data for this image was acquired, Antarctica doubles in size to about 28.5 million square km (or about 11 million square miles), and temperatures in the -60C range are common.This true-color image was compiled from MODIS data gathered March 29, 2002. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  5. Silurian trace fossils in carbonate turbidites from the Alexander Arc of southeastern Alaska

    SciTech Connect

    Soja, C.M. )

    1990-05-01

    Early to Late Silurian (Wenlock-Ludlow) body and trace fossils from the Heceta Formation are preserved in the oldest widespread carbonates in the Alexander terrane of southeastern Alaska. They represent the earliest shelly benthos to inhabit a diversity of marine environments and are important indicators of the early stages in benthic community development within this ancient island arc. The trace fossils are significant because they add to a small but growing body of knowledge about ichnofaunas in deep-water Paleozoic carbonates. Proximal to medial carbonate turbidites yield a low-diversity suite of trace fossils that comprises five distinct types of biogenic structures. Bedding planes reveal simple epichnial burrows (Planolites), cross-cutting burrows (Fucusopsis), and tiny cylindrical burrows. These and other casts, including chondrites( )-like burrow clusters, represent the feeding activities (fodinichnia) of preturbidite animals. Hypichnial burrows and rare endichnial traces reflect the activities of postturbidite animals. Broken and offset traces indicate that infaunal biota commenced burrowing before slumping and subsequent soft-sediment deformation. The abundance and density of trace fossils increases offshore in the medial turbidites associated with a decrease in the size and amount of coarse particles and with an increase in mud and preserved organic material. Although diversity levels are similar in the proximal and medial turbidite facies, they are much lower than in Paleozoic siliciclastic turbidites. This may reflect unfavorable environmental conditions for infaunal biota or paleobiogeographic isolation of the Alexander terrane during the Silurian. A greater use of trace fossils in terrane analysis will help to resolve this issue and should provide new data for reconstructing the paleogeography of circum-Pacific terranes.

  6. Reflexionseigenschaften von Windenergieanlagen im Funkfeld von Funknavigations- und Radarsystemen

    NASA Astrophysics Data System (ADS)

    Sandmann, S.; Divanbeigi, S.; Garbe, H.

    2015-11-01

    Die hier behandelte Untersuchung befasst sich mit den Störungen des elektrischen Feldes einer Doppler Very High Frequency Omnidirectional Radio Range Navigationsanlage (DVOR) in der Gegenwart von Windenergieanlagen (WEA). Hierfür wird die Feldstärke auf 25 konzentrischen Kreisbahnen, sog. Orbit Flights verschiedener Höhen und mit verschiedenen Radien rund um die DVOR-Anlage numerisch simuliert. Insbesondere werden die Einflüsse diverser Parameter der WEA wie deren Anzahl, Position, Rotorwinkel, Turmhöhe und Rotordurchmesser auf die Feldverteilung herausgestellt, sowie die Anwendbarkeit der Simulationsmethode Physical Optics (PO) durch Vergleich der Simulationsergebnisse mit denen der Multi Level Fast Multipol Method (MLFMM) untersucht.

  7. Dr. Wernher Von Braun at a picnic.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun, director of the Marshall Space Flight Center, stakes claim to a table for the picnic celebrating man's first lunar landing. With Dr. Von Braun are his wife, Maria (seated, right), and son, Peter (back to camera). His daughter, Margrit, was also present, but is hidden from view by friends in this view.

  8. Dr. Wernher Von Braun greeting dignitaries.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun, left, greets vice president Spiro T. Agnew in the Launch Control Center for the Apollo 14 mission. Between Dr. Von Braun and Mr. Agnew are their Royal Highnesses, The Prince and Princess of Spain. The royal visitors greeted the launch control team in th enter after the launch of Apollo 14.

  9. Dr. von Braun Tries Out the NBS

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Marshall Space Flight Center (MSFC) Director, Dr. von Braun, is shown fitted with suit and diving equipment as he prepares for a tryout in the MSFC Neutral Buoyancy Simulator (NBS). Weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  10. Walt Disney and Dr. Wernher von Braun

    NASA Technical Reports Server (NTRS)

    1954-01-01

    Dr. Werhner von Braun, then Chief, Guided Missile Development Operation Division at Army Ballistic Missile Agency (ABMA) in Redstone Arsenal, Alabama, was visited by Walt Disney in 1954. In the 1950's, von Braun worked with Disney Studio as a technical director, making three films about space exploration for television. A model of the V-2 rocket is in background.

  11. Dr. Wernher von Braun Laid to Rest

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Dr. Wernher von Braun served as Marshall Space Flight Center's first director from July 1, 1960 until January 27, 1970, when he was appointed NASA Deputy Associate Administrator for Planning. Following World War II, Dr. von Braun and his German colleagues arrived in the United States under Project Paper Clip to continue their rocket development work. In 1950, von Braun and his rocket team were transferred from Ft. Bliss, Texas to Huntsville, Alabama to work for the Army's rocket program at Redstone Arsenal and later, NASA's Marshall Space Flight Center. Under von Braun's leadership, Marshall developed the Saturn V launch vehicle which took Apollo astronauts to the moon. Dr. von Braun died in Alexandria, Va., on June 16, 1977, seven years after his NASA appointment. This photo was taken at the site where he was laid to rest.

  12. Dr. Wernher von Braun In His Office

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Dr. Wernher von Braun served as Marshall Space Flight Center's first director from July 1, 1960 until January 27, 1970, when he was appointed NASA Deputy Associate Administrator for Planning. Following World War II, Dr. von Braun and his German colleagues arrived in the United States under Project Paperclip to continue their rocket development work. In 1950, von Braun and his rocket team were transferred from Ft. Bliss, Texas to Huntsville, Alabama to work for the Army's rocket program at Redstone Arsenal and later, NASA's Marshall Space Flight Center. Under von Braun's leadership, Marshall developed the Saturn V launch vehicle which took Apollo astronauts to the moon. This photo depicts von Braun in his office at MSFC.

  13. The dynamical behaviour of our planetary system. Proceedings. 4th Alexander von Humboldt Colloquium on Celestial Mechanics, Ramsau (Austria), 17 - 23 Mar 1996.

    NASA Astrophysics Data System (ADS)

    Dvorak, R.; Henrard, J.

    1996-03-01

    The following topics were dealt with: celestial mechanics, dynamical astronomy, planetary systems, resonance scattering, Hamiltonian mechanics non-integrability, irregular periodic orbits, escape, dynamical system mapping, fast Fourier method, precession-nutation, Nekhoroshev theorem, asteroid dynamics, the Trojan problem, planet-crossing orbits, Kirkwood gaps, future research, human comprehension limitations.

  14. Qualitative and quantitative behaviour of planetary systems; Proceedings of the 3rd Alexander von Humboldt Colloquium on Celestial Mechanics, Ramsau, Austria, Mar. 29-Apr. 4, 1992

    NASA Astrophysics Data System (ADS)

    Dvorak, R.; Henrard, J.

    1993-06-01

    Topics addressed include planetary theories, the Sitnikov problem, asteroids, resonance, general dynamical systems, and chaos and stability. Particular attention is given to recent progress in the theory and application of symplectic integrators, a computer-aided analysis of the Sitnikov problem, the chaotic behavior of trajectories for the asteroidal resonances, and the resonant motion in the restricted three-body problem. Also discussed are the second order long-period motion of Hyperion, meteorites from the asteroid 6 Hebe, and least squares parameter estimation in chaotic differential equations.

  15. Alloantibodies in von Willebrand disease.

    PubMed

    James, Paula D; Lillicrap, David; Mannucci, Pier M

    2013-08-01

    The development of alloantibodies against von Willebrand factor (VWF) represents a rare but serious complication of treatment of von Willebrand disease (VWD), occurring in ~5% to 10% of type 3 VWD patients. Affected patients can present with a range of symptoms, including lack or loss of hemostatic response to infused VWF concentrates up to anaphylactic reactions in rare cases. It is classically reported in multitransfused patients and occurs most frequently in patients with partial or complete VWF gene deletions. A positive family history of anti-VWF antibodies also appears to be a risk factor. There is a lack of standardization of laboratory methods for antibody identification and characterization. Issues of variability in laboratory approaches as well as the rarity of the complication act as a barrier to future studies. Recombinant factor VIII as well as bypassing agents and immune tolerance have been reported as effective treatments; however, aside from case reports, little exists in the literature to guide management. The imminent clinical availability of recombinant VWF has prompted a resurgence of interest in this area. Additional study is warranted to address the deficiencies in our understanding of this treatment complication.

  16. Clearance of von Willebrand factor.

    PubMed

    Denis, Cécile V; Christophe, Olivier D; Oortwijn, Beatrijs D; Lenting, Peter J

    2008-02-01

    The life cycle of von Willebrand factor (VWF) comprises a number of distinct steps, ranging from the controlled expression of the VWF gene in endothelial cells and megakaryocytes to the removal of VWF from the circulation. The various aspects of VWF clearance have been the objects of intense research in the last few years, stimulated by observations that VWF clearance is a relatively common component of the pathogenesis of type 1 von Willebrand disease (VWD). Moreover, improving the survival of VWF is now considered as a viable therapeutic strategy to prolong the half-life of factor VIII in order to optimise treatment of haemophilia A. The present review aims to provide an overview of recent findings with regard to the molecular basis of VWF clearance. A number of parameters have been identified that influence VWF clearance, including its glycosylation profile and a number of VWF missense mutations. In addition, in-vivo studies have been used to identify cells that contribute to the catabolism of VWF, providing a starting point for the identification of receptors that mediate the cellular uptake of VWF. Finally, we discuss recent data describing chemically modification of VWF as an approach to prolong the half-life of the VWF/FVIII complex.

  17. A double commutant theorem for Murray–von Neumann algebras

    PubMed Central

    Liu, Zhe

    2012-01-01

    Murray–von Neumann algebras are algebras of operators affiliated with finite von Neumann algebras. In this article, we study commutativity and affiliation of self-adjoint operators (possibly unbounded). We show that a maximal abelian self-adjoint subalgebra of the Murray–von Neumann algebra associated with a finite von Neumann algebra is the Murray–von Neumann algebra , where is a maximal abelian self-adjoint subalgebra of and, in addition, is . We also prove that the Murray–von Neumann algebra with the center of is the center of the Murray–von Neumann algebra . Von Neumann’s celebrated double commutant theorem characterizes von Neumann algebras as those for which , where , the commutant of , is the set of bounded operators on the Hilbert space that commute with all operators in . At the end of this article, we present a double commutant theorem for Murray–von Neumann algebras. PMID:22543165

  18. Indikatorenbasierte Bewertung von Entwurfsentscheidungen auf Systemebene

    NASA Astrophysics Data System (ADS)

    Freier, M.; Wenzler, A.; Mayer, T.; Gerlach, J.; Rosenstiel, W.

    2013-07-01

    Bei dem Entwurf von anwendungsspezifischen integrierten Schaltungen muss ein Entwickler zusätzliche Funktionen integrieren und die zunehmende Komplexität bewältigen. Für die Reduzierung der Kosten bleibt weiterhin die Verkürzung der benötigten Entwicklungszeit ein Ziel. Ein entscheidender Faktor dabei ist die zuverlässige Absicherung von Entwurfsentscheidungen in einer frühen Entwurfsphase. In der vorliegenden Arbeit wird eine Methode vorgestellt, die eine Bewertung von Entwurfsentscheidungen bei Systemmodellen mittels automatisch ermittelter Indikatoren ermöglichen soll. Die Systemmodelle können mit der Entwurfsumgebung MATLAB/Simulink oder in SystemC beschrieben sein.

  19. James Alexander Lindsay (1856–1931), and his clinical axioms and aphorisms

    PubMed Central

    Breathnach, Caoimhghin S; Moynihan, John B

    2012-01-01

    John Alexander Lindsay was born at Fintona, county Tyrone in 1856, and at the age of 23 he graduated in medicine at the Royal University of Ireland. After two years in London and Europe he returned to Belfast to join the staff at the Royal Victoria Hospital and in 1899 he was appointed to the professorship of medicine. He was valued by the students for his clarity and by his colleagues for his many extracurricular contributions to the medical profession in the positions entrusted to him. He published monographs on Diseases of the Lungs, and the Climatic Treatment of Consumption, but his later Medical Axioms show his deep appreciation of studied clinical observation. Although practice was changing in the new century Lindsay displayed an ability to change with the new requirements, as evidenced by his lecture on electrocardiography as president of the section of medicine of the Royal Academy of Medicine in Ireland in 1915. He was impressed by the way the string galvanometer changed attention from stenosis and incompetence of the valves to the cardiac musculature, but rightly suspected that there was more to be told about the state of the myocardium than Einthoven's three leads revealed. His death occurred in Belfast in 1931. PMID:23620615

  20. James Alexander Lindsay (1856-1931), and his clinical axioms and aphorisms.

    PubMed

    Breathnach, Caoimhghin S; Moynihan, John B

    2012-09-01

    John Alexander Lindsay was born at Fintona, county Tyrone in 1856, and at the age of 23 he graduated in medicine at the Royal University of Ireland. After two years in London and Europe he returned to Belfast to join the staff at the Royal Victoria Hospital and in 1899 he was appointed to the professorship of medicine. He was valued by the students for his clarity and by his colleagues for his many extracurricular contributions to the medical profession in the positions entrusted to him. He published monographs on Diseases of the Lungs, and the Climatic Treatment of Consumption, but his later Medical Axioms show his deep appreciation of studied clinical observation. Although practice was changing in the new century Lindsay displayed an ability to change with the new requirements, as evidenced by his lecture on electrocardiography as president of the section of medicine of the Royal Academy of Medicine in Ireland in 1915. He was impressed by the way the string galvanometer changed attention from stenosis and incompetence of the valves to the cardiac musculature, but rightly suspected that there was more to be told about the state of the myocardium than Einthoven's three leads revealed. His death occurred in Belfast in 1931.

  1. Childhood Picture of Dr. von Braun

    NASA Technical Reports Server (NTRS)

    1912-01-01

    This is a childhood picture of Dr. von Braun (center) with his brothers. Dr. Wernher von Braun was born in Wirsitz, Germany, March 23, 1912. His childhood dreams of marned space flight were fulfilled when giant Saturn rockets, developed under his direction at NASA's Marshall Space Flight Center, boosted the manned Apollo spacecraft to the Moon. His life was dedicated to expanding man's knowledge through the exploration of space.

  2. Dr. von Braun With Management Team

    NASA Technical Reports Server (NTRS)

    1961-01-01

    Dr. von Braun is shown in this photograph, which was probably taken in the early 1960s, with members of his management team. Pictured from left to right are, Werner Kuers, Director of the Manufacturing Engineering Division; Dr. Walter Haeussermarn, Director of the Astrionics Division; Dr. William Mrazek, Propulsion and Vehicle Engineering Division; Dr. von Braun; Dieter Grau, Director of the Quality Assurance Division; Dr. Oswald Lange, Director of the Saturn Systems Office; and Erich Neubert , Associate Deputy Director for Research and Development.

  3. Bathymetric gradients within a Paleozoic Island Arc, southeastern Alaska (Alexander Terrane)

    SciTech Connect

    Soja, C.M. )

    1990-05-01

    Early to Late Silurian (Wenlock-Ludlow) limestones belonging to the Heceta Formation reflect bathymetric gradients within the ancient island arc exposed in the Alexander terrane of southeastern Alaska. These rocks record the earliest occurrence of widespread carbonate deposition in the region and represent the earliest foundation for shallow-water platform development within the arc. The excellent preservation of platform, platform margin, and slope deposits contrasts with the poor preservation of many marine sediments that originated within other island arcs. Hence, these limestones provide important insights into the styles, processes, and bathymetry of carbonate deposition in island arcs. Carbonate depositional sites within the arc extended laterally from nearshore intertidal and relatively shallow subtidal zones of a marine platform, to the seaward margins of a rimmed shelf, and into deeper subtidal areas of a slope environment. Fossiliferous deposits that originated on the platform comprise a diversity of shelly benthos, including corals and stromatoporoids in growth position. Dasycladacean algae, oncoids, and Amphipora also indicate shallow-water conditions. Organic buildups and reefs were constructed by cyanobacteria, massive stromatoporoids, corals, and algae at the platform margin. Deposition beyond the seaward edge of the shelf is evident from the carbonate turbidites that consist of skeletal debris of shallow-water derivation and an absence of coarse siliciclastic detritus. Sedimentation and resedimentation along a bathymetric gradient within the arc is especially well illustrated by the carbonate breccias that are enclosed within these deep subtidal sediments. They comprise detached stromatolites and clasts of shallow-water origin that were derived from the platform and its margin during periodic slumping of the shelf edge.

  4. Death by polonium-210: lessons learned from the murder of former Soviet spy Alexander Litvinenko.

    PubMed

    McFee, Robin B; Leikin, Jerrold B

    2009-02-01

    The medical response to radiation--whether the result of radiological warfare, terrorist deployment of improvised radiation dispersal weapons, political assassination, occupational or industrial accidents or the medically radiated patient remains one of the least taught among all disciplines within medical education. In the aftermath of 9/11 among medical vulnerabilities to toxicant threats, of all the categories of weapons of mass destruction (WMD)--whether using the CBRNE (chemical, biological, radiological, nuclear, explosive) or NBC (nuclear, biological, chemical) acronym--radiation is the least taught in professional schools, responder cultures or civil preparedness organizations. To date, few health care professionals (HCP) possess the fundamental knowledge or skills to identify and diagnose, let alone treat a radiation victim; this vulnerability made even more obvious in the aftermath of the high profile assassination of former Russian agent Alexander Litvinenko. He was poisoned with Polonium210. Radioactive substances are ubiquitous with radiation sources being in or transported through virtually every region nationwide. It is essential to increase preparedness among community and rural health care facilities as well as urban and university hospitals. Managing radiation injuries effectively requires access to specialized equipment and expertise. Radiation sickness is progressive and may require acute, critical and long-term care throughout the course of illness. Regardless of the source, preparedness rests upon acknowledging a threat exists and dedicating the resources to address the risks including the enhancement of training and equipment. Mass or individual exposures to radiation present unique challenges to the entire response continuum from law enforcement, first responders and emergency medical care. Increased education about and practice in responding to radiological threats is essential to enhance preparedness.

  5. Neuromechanical interference of posture on movement: evidence from Alexander technique teachers rising from a chair

    PubMed Central

    Cacciatore, Timothy W.; Mian, Omar S.; Peters, Amy

    2014-01-01

    While Alexander technique (AT) teachers have been reported to stand up by shifting weight gradually as they incline the trunk forward, healthy untrained (HU) adults appear unable to rise in this way. This study examines the hypothesis that HU have difficulty rising smoothly, and that this difficulty relates to reported differences in postural stiffness between groups. A wide range of movement durations (1–8 s) and anteroposterior foot placements were studied under the instruction to rise at a uniform rate. Before seat-off (SO) there were clear and profound performance differences between groups, particularly for slower movements, that could not be explained by strength differences. For each movement duration, HU used approximately twice the forward center-of-mass (CoM) velocity and vertical feet-loading rate as AT. For slow movements, HU violated task instruction by abruptly speeding up and rapidly shifting weight just before SO. In contrast, AT shifted weight gradually while smoothly advancing the CoM, achieving a more anterior CoM at SO. A neuromechanical model revealed a mechanism whereby stiffness affects standing up by exacerbating a conflict between postural and balance constraints. Thus activating leg extensors to take body weight hinders forward CoM progression toward the feet. HU's abrupt weight shift can be explained by reliance on momentum to stretch stiff leg extensors. AT's smooth rises can be explained by heightened dynamic tone control that reduces leg extensor resistance and improves force transmission across the trunk. Our results suggest postural control shapes movement coordination through a dynamic “postural frame” that affects the resistive behavior of the body. PMID:25085609

  6. Project Alexander the Great: a study on the world proliferation of bioengineering/biomedical engineering education.

    PubMed

    Abu-Faraj, Ziad O

    2008-01-01

    Bioengineering/Biomedical Engineering is considered amongst the most reputable fields within the global arena, and will likely be the primer for any future breakthroughs in Medicine and Biology. Bioengineering/biomedical engineering education has evolved since late 1950s and is undergoing advancement in leading academic institutions worldwide. This paper delineates an original study on the world proliferation of bioengineering/biomedical engineering education and bears the name 'Project Alexander the Great'. The initial step of the project was to survey all 10448 universities, recognized by the International Association of Universities, spread among the 193 member states of the United Nations within the six continents. The project aims at identifying, disseminating, and networking, through the world-wide-web, those institutions of higher learning that provide bioengineering/biomedical engineering education. The significance of this project is multifold: i) the inception of a web-based 'world-map' in bioengineering/biomedical engineering education for the potential international student desiring to pursue a career in this field; ii) the global networking of bioengineering/biomedical engineering academic/research programs; iii) the promotion of first-class bioengineering/biomedical engineering education and the catalysis of global proliferation of this field; iv) the erection of bridges among educational institutions, industry, and professional societies or organizations involved in Bioengineering/Biomedical Engineering; and v) the catalysis in the establishment of framework agreements for cooperation among the identified institutions offering curricula in this field. This paper presents the results obtained from Africa and North America. The whole project is due to be completed by 2009.

  7. The origin of Rosenthal fibers and their contributions to astrocyte pathology in Alexander disease.

    PubMed

    Sosunov, Alexander A; McKhann, Guy M; Goldman, James E

    2017-03-31

    Rosenthal fibers (RFs) are cytoplasmic, proteinaceous aggregates. They are the pathognomonic feature of the astrocyte pathology in Alexander Disease (AxD), a neurodegenerative disorder caused by heterozygous mutations in the GFAP gene, encoding glial fibrillary acidic protein (GFAP). Although RFs have been known for many years their origin and significance remain elusive issues. We have used mouse models of AxD based on the overexpression of human GFAP (transgenic, TG) and a point mutation in mouse GFAP (knock-in, KI) to examine the formation of RFs and to find astrocyte changes that correlate with the appearance of RFs. We found RFs of various sizes and shapes. The smallest ones appear as granular depositions on intermediate filaments. These contain GFAP and the small heat shock protein, alphaB-crystallin. Their aggregation appears to give rise to large RFs. The appearance of new RFs and the growth of previously formed RFs occur over time. We determined that DAPI is a reliable marker of RFs and in parallel with Fluoro-Jade B (FJB) staining defined a high variability in the appearance of RFs, even in neighboring astrocytes. Although many astrocytes in AxD with increased levels of GFAP and with or without RFs change their phenotype, only some cells with large numbers of RFs show a profound reconstruction of cellular processes, with a loss of fine distal processes and the appearance of large, lobulated nuclei, likely due to arrested mitosis. We conclude that 1) RFs appear to originate as small, osmiophilic masses containing both GFAP and alphaB-crystallin deposited on bundles of intermediate filaments. 2) RFs continue to form within AxD astrocytes over time. 3) DAPI is a reliable marker for RFs and can be used with immunolabeling. 4) RFs appear to interfere with the successful completion of astrocyte mitosis and cell division.

  8. [Biology of von Willebrand factor].

    PubMed

    Girma, Jean-Pierre

    2006-01-01

    Von Willebrand factor (VWF) is a multimeric glycoprotein synthesized by megakaryocytes and endothelial cells. It is stored in platelets and endothelial cells and secreted towards subendothelium and plasma. VWF multimers consist of linear arrangements of identical subunits with a molecular weight of 270 kDa. The longest multimers reach more than 20 x 10(6) Da in storage granules. In the circulation, the multimer size is limited by the specific protease ADAMTS13. In primary hemostasis, VWF plays a key role as a molecular bridge in adhesion between platelets and subendothelium and between platelets during their aggregation. These functions, which involve the interaction with platelet glycoprotein lb, are mainly enhanced by VWF immobilization onto hydrophobic surfaces (collagen, cell membrane) and by high shear rates found in microcirculation and stenosed arteries. In these functions, the higher molecular weight forms are the most efficient. Under such hemodynamic conditions, proteolytic activity of ADAMTS13 is also optimal and limits the multimer size to about 15 x 10(6) Da as soon as their secretion. Thus ADAMTS13 appears as a key physiologic regulator of the VWF platelet functions. In the microcirculation, the lack of ADAMTS13 activity can result in the formation of VWF-rich platelet aggregates responsible for thrombotic thrombocytopenic purpura.

  9. Von Karman re-visited

    NASA Astrophysics Data System (ADS)

    McEligot, Donald M.; Nolan, Kevin P.; Walsh, Edmond J.

    2012-11-01

    A number of authors have presented extended versions of the integral momentum equation, allowing for perturbations or fluctuations in the boundary layer. ``Conventional wisdom'' is that these added terms can be neglected and one can apply the von Karman version directly. For two-dimensional turbulent boundary layers at high Reynolds numbers, experience shows this assumption to be reasonable. However, recent examination of entropy generation in bypass transition with zero pressure gradient shows a term for turbulence energy convection can be important in determining the energy dissipation coefficient [Walsh et al., JFE 2011]. The present study employs the direct numerical simulations of Zaki and Durbin [JFM 2006] for bypass transition with streamwise pressure gradients to quantify the additional normal stress term when estimating the skin friction coefficient via a momentum balance. It is found that this term becomes noticeable in the pre-transitional laminar boundary layer and can exceed forty per cent of Cf in the transition region. Thus, it should be included in such calculations. Partly supported by U. S. DoE EPSCoR office.

  10. Bokan Mountain peralkaline granitic complex, Alexander terrane (southeastern Alaska): evidence for Early Jurassic rifting prior to accretion with North America

    USGS Publications Warehouse

    Dostal, Jaroslav; Karl, Susan M.; Keppie, J. Duncan; Kontak, Daniel J.; Shellnutt, J. Gregory

    2013-01-01

    The circular Bokan Mountain complex (BMC) on southern Prince of Wales Island, southernmost Alaska, is a Jurassic peralkaline granitic intrusion about 3 km in diameter that crosscuts igneous and metasedimentary rocks of the Alexander terrane. The BMC hosts significant rare metal (rare earth elements, Y, U, Th, Zr, and Nb) mineralization related to the last stage of BMC emplacement. U–Pb (zircon) and 40Ar/39Ar (amphibole and whole-rock) geochronology indicates the following sequence of intrusive activity: (i) a Paleozoic basement composed mainly of 469 ± 4 Ma granitic rocks; (ii) intrusion of the BMC at 177 ± 1 Ma followed by rapid cooling through ca. 550 °C at 176 ± 1 Ma that was synchronous with mineralization associated with vertical, WNW-trending pegmatites, felsic dikes, and aegirine–fluorite veins and late-stage, sinistral shear deformation; and (iii) intrusion of crosscutting lamprophyre dikes at >150 Ma and again at ca. 105 Ma. The peralkaline nature of the BMC and the WNW trend of associated dikes suggest intrusion during NE–SW rifting that was followed by NE–SW shortening during the waning stages of BMC emplacement. The 177 Ma BMC was synchronous with other magmatic centres in the Alexander terrane, such as (1) the Dora Bay peralkaline stock and (2) the bimodal Moffatt volcanic suite located ~30 km north and ~100 km SE of the BMC, respectively. This regional magmatism is interpreted to represent a regional extensional event that precedes deposition of the Late Jurassic – Cretaceous Gravina sequence that oversteps the Wrangellia and Alexander exotic accreted terranes and the Taku and Yukon–Tanana pericratonic terranes of the Canadian–Alaskan Cordillera.

  11. An MRI Von Economo - Koskinas atlas.

    PubMed

    Scholtens, Lianne H; de Reus, Marcel A; de Lange, Siemon C; Schmidt, Ruben; van den Heuvel, Martijn P

    2016-12-28

    The cerebral cortex displays substantial variation in cellular architecture, a regional patterning that has been of great interest to anatomists for centuries. In 1925, Constantin von Economo and George Koskinas published a detailed atlas of the human cerebral cortex, describing a cytoarchitectonic division of the cortical mantle into over 40 distinct areas. Von Economo and Koskinas accompanied their seminal work with large photomicrographic plates of their histological slides, together with tables containing for each described region detailed morphological layer-specific information on neuronal count, neuron size and thickness of the cortical mantle. Here, we aimed to make this legacy data accessible and relatable to in vivo neuroimaging data by constructing a digital Von Economo - Koskinas atlas compatible with the widely used FreeSurfer software suite. In this technical note we describe the procedures used for manual segmentation of the Von Economo - Koskinas atlas onto individual T1 scans and the subsequent construction of the digital atlas. We provide the files needed to run the atlas on new FreeSurfer data, together with some simple code of how to apply the atlas to T1 scans within the FreeSurfer software suite. The digital Von Economo - Koskinas atlas is easily applicable to modern day anatomical MRI data and is made publicly available online.

  12. Sulfation of von Willebrand factor

    SciTech Connect

    Carew, J.A.; Browning, P.J.; Lynch, D.C. )

    1990-12-15

    von Willebrand factor (vWF) is a multimeric adhesive glycoprotein essential for normal hemostasis. We have discovered that cultured human umbilical vein endothelial cells incorporate inorganic sulfate into vWF. Following immunoisolation and analysis by polyacrylamide or agarose gel electrophoresis, metabolically labeled vWF was found to have incorporated (35S)-sulfate into all secreted multimer species. The time course of incorporation shows that sulfation occurs late in the biosynthesis of vWF, near the point at which multimerization occurs. Quantitative analysis suggests the presence, on average, of one molecule of sulfate per mature vWF subunit. Virtually all the detectable sulfate is released from the mature vWF subunit by treatment with endoglycosidases that remove asparagine-linked carbohydrates. Sulfated carbohydrate was localized first to the N-terminal half of the mature subunit (amino acids 1 through 1,365) by partial proteolytic digestion with protease V8; and subsequently to a smaller fragment within this region (amino acids 273 through 511) by sequential digestions with protease V8 and trypsin. Thus, the carbohydrate at asparagine 384 and/or 468 appears to be the site of sulfate modification. Sodium chlorate, an inhibitor of adenosine triphosphate-sulfurylase, blocks sulfation of vWF without affecting either the ability of vWF to assemble into high molecular weight multimers or the ability of vWF multimers to enter Weible-Palade bodies. The stability of vWF multimers in the presence of an endothelial cell monolayer also was unaffected by the sulfation state. Additionally, we have found that the cleaved propeptide of vWF is sulfated on asparagine-linked carbohydrate.

  13. Dr. Wernher Von Braun with Dr. Christian Barnard.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Christian Barnard Tours Marshall Space Flight Center. Shown in Dr. Von Braun's office are (left to right): Dr. Ernst Sthulinger, a representative from General Electric, Dr. Wernher Von Braun, Dr. Christian Barnard, and Dr. Eberhard Rees.

  14. Adult-onset Alexander disease: a series of eleven unrelated cases with review of the literature.

    PubMed

    Pareyson, Davide; Fancellu, Roberto; Mariotti, Caterina; Romano, Silvia; Salmaggi, Andrea; Carella, Francesco; Girotti, Floriano; Gattellaro, Grazietta; Carriero, Maria Rita; Farina, Laura; Ceccherini, Isabella; Savoiardo, Mario

    2008-09-01

    Alexander disease (AD) in its typical form is an infantile lethal leucodystrophy, characterized pathologically by Rosenthal fibre accumulation. Following the identification of glial fibrillary acidic protein (GFAP) gene as the causative gene, cases of adult-onset AD (AOAD) are being described with increasing frequency. AOAD has a different clinical and neuroradiological presentation with respect to early-onset AD, as abnormalities are mainly concentrated in the brainstem-spinal cord junction. We report detailed clinical and genetic data of 11 cases of AOAD, observed over a 4-year period, and a review of the previously reported 25 cases of genetically confirmed AOAD. In our series, onset occurred as late as age 62, and up to 71 in an affected deceased relative. Most cases appeared sporadic, but family history may be misleading. The most frequent symptoms were related to bulbar dysfunction-with dysarthria, dysphagia, dysphonia (seven patients)-, pyramidal involvement (seven patients) and cerebellar ataxia (seven patients). Four patients had palatal myoclonus. Sleep disorders were also observed (four cases). Bulbar symptoms, however, were infrequent at onset and two symptomatic patients had an almost pure pyramidal involvement. Two subjects were asymptomatic. Misdiagnosis at presentation was frequent and MRI was instrumental in suggesting the correct diagnosis by showing, in all cases, mild to severe atrophy of the medulla oblongata extending caudally to the cervical spinal cord. In ten patients, molecular studies revealed six novel missense mutations and three previously reported changes in GFAP. The last typical patient carried no definitely pathogenic mutation, but a missense variant (p.D157N), supposedly a rare polymorphism. Revision of the literature and the present series indicate that the clinical picture is not specific, but AOAD must be considered in patients of any age with lower brainstem signs. When present, palatal myoclonus is strongly suggestive

  15. Liouville-von Neumann molecular dynamics

    NASA Astrophysics Data System (ADS)

    Jakowski, Jacek; Morokuma, Keiji

    2009-06-01

    We present a novel first principles molecular dynamics scheme, called Liouville-von Neumann molecular dynamics, based on Liouville-von Neumann equation for density matrices propagation and Magnus expansion of the time-evolution operator. The scheme combines formally accurate quantum propagation of electrons represented via density matrices and a classical propagation of nuclei. The method requires a few iterations per each time step where the Fock operator is formed and von Neumann equation is integrated. The algorithm (a) is free of constraint and fictitious parameters, (b) avoids diagonalization of the Fock operator, and (c) can be used in the case of fractional occupation as in metallic systems. The algorithm is very stable, and has a very good conservation of energy even in cases when a good quality conventional Born-Oppenheimer molecular dynamics trajectories is difficult to obtain. Test simulations include initial phase of fullerene formation from gaseous C2 and retinal system.

  16. State of the art: von Willebrand disease.

    PubMed

    James, A H; Eikenboom, J; Federici, A B

    2016-07-01

    The State of the Art in von Willebrand disease (VWD) has been impacted not only by discoveries in the field of haemostasis, but also by changes in practice in other fields. The development of bleeding assessment tools has led to the clarification of bleeding symptoms and phenotype in VWD. New discoveries in the biology and genetics of von Willebrand factor (VWF) are challenging our existing diagnostics and classification(s). An improved understanding of reproductive physiology and the pathology of VWD along with changing obstetric, gynaecologic and haemostatic therapies necessitate an evolving response to the care of women with VWD. The survival of patients with autoimmune disease, malignancies and congenital heart disease along with increasing use of circulatory support devices and extracorporeal membrane oxygenation is increasing the prevalence of acquired von Willebrand syndrome. In each of these challenges, there are opportunities to improve the care of our patients with VWD.

  17. Treatment of the acquired von Willebrand syndrome.

    PubMed

    Budde, Ulrich; Scheppenheim, Sonja; Dittmer, Rita

    2015-12-01

    Acquired von Willebrand syndrome (aVWS) accounts for 22% of patients with abnormal von Willebrand factor. Most patients with known pathophysiological mechanisms suffer from cardiovascular, myeloproliferative and lymphoproliferative disorders. Less frequent associations are of autoimmune origin, due to hyperfibrinolysis, adsorption to tumor cells, reduced synthesis and prolonged circulation. The mechanisms leading to aVWS is hitherto not known in patients with liver and kidney diseases, drug use, glycogen storage disease, virus infections and at least 18 other disease entities. Diagnosis is complicated by the battery of tests needed, and their inherent rather low sensitivity and specificity for aVWS. Thus, even in acute bleeding situations it may take days until a firm diagnosis is settled and specific therapies can be initiated. The main aim is to shed more light onto this, compared with inherited von Willebrand disease, rare disease which affects at least 2-3% of the older population.

  18. Biosynthesis, processing and secretion of von Willebrand factor: biological implications.

    PubMed

    de Wit, T R; van Mourik, J A

    2001-06-01

    von Willebrand factor is a multimeric plasma glycoprotein that is required for normal haemostasis. von Willebrand factor is synthesized by endothelial cells and megakaryocytes, and originates from its precursor pro-von Willebrand factor. The endoproteolytic processing of pro-von Willebrand factor results in mature von Willebrand factor and von Willebrand factor propeptide (also known as von Willebrand Ag II). In endothelial cells, the propeptide controls the polymerization and subsequent targeting of von Willebrand factor to the storage vesicles, the so-called Weibel-Palade bodies. Upon stimulation of the endothelial cells, the Weibel-Palade bodies are translocated to the plasma membrane of the cell, and mature von Willebrand factor and its propeptide are co-secreted. After release, these polypeptides have divergent fates and serve different biological functions. Mature von Willebrand factor both controls platelet adhesion and aggregation at sites of vascular injury and acts as a chaperone protein for coagulation factor VIII. The von Willebrand factor propeptide may serve a role in modulating inflammatory processes. This still growing body of information indicates that the biological function of the von Willebrand factor gene product is more diverse than was previously thought.

  19. [Research advance in von Willebrand factor].

    PubMed

    Li, Xue-Mei; Jiang, Miao; Zhao, Yi-Ming

    2013-06-01

    von Willebrand factor (vWF) is a multimeric glycoprotein exclusively synthesized in endothelial cells and megakaryocytes. It plays important roles in the primary and secondary haemostasis. Deficiency or dysfunction of vWF may cause von Willebrand disease (vWD), and overexpression of vWF may cause thrombosis. Making an intensive study on vWF will help us to understand the pathophysiology, diagnosis and treatment of vWF-related diseases, such as vWD, TTP, venous thrombosis, stroke, and so on. In this article, the regulation of vWF activity and its relation with diseases mentioned above are reviewed.

  20. Mittelwert- und Arbeitstaktsynchrone Simulation von Dieselmotoren

    NASA Astrophysics Data System (ADS)

    Zahn, Sebastian

    Getrieben durch die immer restriktiveren Anforderungen an das Emissions- und Verbrauchsverhalten moderner Verbrennungsmotoren steigt die Komplexität von Motormanagementsystemen mit jeder Modellgeneration an. Damit geht nicht nur eine Zunahme des Softwareumfangs von Steuergeräten sondern zugleich ein deutlicher Anstieg des Applikations-, Vermessungs- und Testaufwandes einher. Zur Effizienzsteigerung des Software- und Funktionsentwicklungsprozesses haben sich daher in der Automobilindustrie sowie in Forschungsinstituten verschiedene modell- und simulationsbasierte Methoden wie die Model-in-the-Loop (MiL) Simulation, die Software-in-the-Loop (SiL) Simulation, das Rapid Control Prototyping (RCP) sowie die Hardware-in-the-Loop (HiL) Simulation etabliert.

  1. Level-Set-Segmentierung von Rattenhirn MRTs

    NASA Astrophysics Data System (ADS)

    Eiben, Björn; Kunz, Dietmar; Pietrzyk, Uwe; Palm, Christoph

    In dieser Arbeit wird die Segmentierung von Gehirngewebe aus Kopfaufnahmen von Ratten mittels Level-Set-Methoden vorgeschlagen. Dazu wird ein zweidimensionaler, kontrastbasierter Ansatz zu einem dreidimensionalen, lokal an die Bildintensität adaptierten Segmentierer erweitert. Es wird gezeigt, dass mit diesem echten 3D-Ansatz die lokalen Bildstrukturen besser berücksichtigt werden können. Insbesondere Magnet-Resonanz-Tomographien (MRTs) mit globalen Helligkeitsgradienten, beispielsweise bedingt durch Oberfiächenspulen, können auf diese Weise zuverlässiger und ohne weitere Vorverarbeitungsschritte segmentiert werden. Die Leistungsfähigkeit des Algorithmus wird experimentell an Hand dreier Rattenhirn-MRTs demonstriert.

  2. Laboratory diagnosis of von Willebrand disease.

    PubMed

    Roberts, J C; Flood, V H

    2015-05-01

    Von Willebrand disease (VWD) is considered the most common inherited bleeding disorder and may also be the most difficult to diagnose. Clinical symptoms of VWD include predominantly mild mucosal bleeding; surgical bleeding may occur with specific challenges and joint bleeding can occur in the most severe forms. A family history either of diagnosed VWD or of bleeding symptoms is typically present. Laboratory diagnosis requires a series of assays of von Willebrand factor (VWF) quantity and function, and factor VIII activity, with no single straightforward diagnostic test available to either confirm or exclude the diagnosis. Newer assays of VWF function are becoming more available and useful in determining the laboratory diagnosis of VWD.

  3. Paleomagnetism and geochronology of 23 Ma gabbroic intrusions in the Keku Strait, Alaska, and implications for the Alexander Terrane

    USGS Publications Warehouse

    Haeussler, Peter J.; Coe, Robert S.; Renne, Paul R.

    1992-01-01

    Samples of Tertiary gabbro from 24 sites in the Keku Strait, Alaska, help constrain the displacement history of the Alexander terrane. Step heating experiments on a plagioclase separate from these previously undated intrusions indicate a discordant 40Ar/39Ar age of 23.1 ± 1.7 Ma. The characteristic magnetization resides in magnetite, is easily isolated by thermal and alternating field demagnetization, and has both normal and reversed polarities. The mean paleomagnetic pole, with no structural correction, is latitude 87.1°N, longitude 141.6°E, A95 = 10.1°, with N = 20 sites. This pole indicates insignificant tectonic displacement (0.5° ± 8.2° southward) and rotation (0.6° ± 15.2° counterclockwise). We therefore conclude that any northward displacement or vertical axis rotation of the Alexander terrane, and/or tilting in the vicinity of the Keku Strait must have occurred before 23 Ma.

  4. Revision of Tipula (Yamatotipula) stackelbergi Alexander (Diptera, Tipulidae), and a short discussion on subspecies among crane flies

    PubMed Central

    Salmela, Jukka

    2012-01-01

    Abstract All available type material of Tipula stackelbergi Alexander, Tipula usuriensis Alexander and Tipula subpruinosa Mannheims were examined. Tipula (Yamatotipula) stackelbergi stat. rev. is elevated from a subspecies of Tipula (Yamatotipula) pruinosa Wiedemann to a valid species. Two new synonyms are proposed: Tipula usuriensis syn. n. proved to be a junior synonym of. Tipula (Yamatotipula) pruinosa and Tipula subpruinosa syn. n. a junior synonym of Tipula (Yamatotipula) freyana Lackschewitz. Tipula (Yamatotipula) stackelbergi is redescribed, male and female terminalia of Tipula (Yamatotipula) pruinosa are illustrated and discussed. Female terminalia of Tipula (Yamatotipula) freyana are described and illustrated for the first time. A key to both sexes of Tipula (Yamatotipula) stackelbergi and Tipula (Yamatotipula) pruinosa, and a key to females of Tipula (Yamatotipula) chonsaniana, Tipula (Yamatotipula) freyana and Tipula (Yamatotipula) moesta are provided. Subspecies are not uncommon among crane flies, but their ranges and traits are poorly known. An interdisciplinary approach (genetics, ecology, taxonomy) is suggested if subspecific ranks are to be used in tipuloid systematics. PMID:22303125

  5. The metallogeny of Late Triassic rifting of the Alexander terrane in southeastern Alaska and northwestern British Columbia

    USGS Publications Warehouse

    Taylor, C.D.; Premo, W.R.; Meier, A.L.; Taggart, J.E.

    2008-01-01

    A belt of unusual volcanogenic massive sulfide (VMS) occurrences is located along the eastern margin of the Alexander terrane throughout southeastern Alaska and northwestern British Columbia and exhibits a range of characteristics consistent with a variety of syngenetic to epigenetic deposit types. Deposits within this belt include Greens Creek and Windy Craggy, the economically most significant VMS deposit in Alaska and the largest in North America, respectively. The occurrences are hosted by a discontinuously exposed, 800-km-long belt of rocks that consist of a 200- to 800-m-thick sequence of conglomerate, limestone, marine elastic sedimentary rocks, and tuff intercalated with and overlain by a distinctive unit of mafic pyroclastic rocks and pillowed flows. Faunal data bracket the age of the host rocks between Anisian (Middle Triassic) and late Norian (late Late Triassic). This metallogenic belt is herein referred to as the Alexander Triassic metallogenic belt. The VMS occurrences show systematic differences in degree of structural control, chemistry, and stratigraphic setting along the Alexander Triassic metallogenic belt that suggest important spatial or temporal changes in the tectonic environment of formation. At the southern end of the belt, felsic volcanic rocks overlain by shallow-water limestones characterize the lower part of the sequence. In the southern and middle portion of the belt, a distinctive pebble conglomerate marks the base of the section and is indicative of high-energy deposition in a near slope or basin margin setting. At the northern end of the belt the conglomerates, limestones, and felsic volcanic rocks are absent and the belt is composed of deep-water sedimentary and mafic volcanic rocks. This northward change in depositional environment and lithofacies is accompanied by a northward transition from epithermal-like structurally controlled, discontinuous, vein- and pod-shaped, Pb-Zn-Ag-Ba-(Cu) occurrences with relatively simple mineralogy

  6. Dr. Wernher Von Braun presents a certificate

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (left), director of the Marshall Space Flight Center, presents a humorous certificate to Major General Charles W. Eifler, commanding general of Redstone Arsenal, at the close of a farewell luncheon for the general prior to General Eifler moving to a new European duty station.

  7. [The Costantin Von Economo's lethargic encefalitis

    PubMed

    Pistacchio, E.

    1998-01-01

    Starting from the Constantin Von Economo's description of a "new" disease, the lethargic encephalitis, the author delineates the history of an infectious sleeping sickness that caused epidemics in Europe from 1917 to 1928 and led to create, in Italy, the "Institutes for Encephalitis".

  8. Dr. von Braun Visits Huntsville Boys Club

    NASA Technical Reports Server (NTRS)

    1961-01-01

    Dr. von Braun, Director of Marshall Space Flight Center (MSFC) and chairman of this year's United Givers Fund (UGF) drive at MSFC, takes time out from the problems of sending a man to the Moon to talk baseball with 11-year-old Randy Smith at the Huntsville Boys Club.

  9. Dr. von Braun Discusses 'Bottle Suit' Concept

    NASA Technical Reports Server (NTRS)

    1954-01-01

    Dr. Wernher von Braun (center), then Chief of the Guided Missile Development Division at Redstone Arsenal, Alabama, discusses a 'bottle suit' model with Dr. Heinz Haber (left), an expert on aviation medicine, and Willey Ley, a science writer on rocketry and space exploration. The three men were at the Disney studios appearing in the motion picture, entitled 'Man in Space.'

  10. A note on derivations of Murray–von Neumann algebras

    PubMed Central

    Kadison, Richard V.; Liu, Zhe

    2014-01-01

    A Murray–von Neumann algebra is the algebra of operators affiliated with a finite von Neumann algebra. In this article, we first present a brief introduction to the theory of derivations of operator algebras from both the physical and mathematical points of view. We then describe our recent work on derivations of Murray–von Neumann algebras. We show that the “extended derivations” of a Murray–von Neumann algebra, those that map the associated finite von Neumann algebra into itself, are inner. In particular, we prove that the only derivation that maps a Murray–von Neumann algebra associated with a factor of type II1 into that factor is 0. Those results are extensions of Singer’s seminal result answering a question of Kaplansky, as applied to von Neumann algebras: The algebra may be noncommutative and may even contain unbounded elements. PMID:24469831

  11. Alexander Graham Bell's Patent for the Telephone and Thomas Edison's Patent for the Electric Lamp. The Constitution Community: The Development of the Industrial United States (1870-1900).

    ERIC Educational Resources Information Center

    Schur, Joan Brodsky

    In 1876 Americans held a Centennial Exhibition in Philadelphia (Pennsylvania) to celebrate the nation's birth 100 years earlier. Machinery Hall drew the most admiration and wonder. Alexander Graham Bell exhibited the first telephone, and Thomas Alva Edison presented the automatic telegraph, one of more than 1,000 inventions he would patent in his…

  12. The Question of Sign-Language and the Utility of Signs in the Instruction of the Deaf: Two Papers by Alexander Graham Bell (1898)

    ERIC Educational Resources Information Center

    Marschark, M.

    2005-01-01

    Alexander Graham Bell is often portrayed as either hero or villain of deaf individuals and the Deaf community. His writings, however, indicate that he was neither, and was not as clearly definite in his beliefs about language as is often supposed. The following two articles, reprinted from The Educator (1898), Vol. V, pp. 3?4 and pp. 38?44,…

  13. Discuss: If Essays Are Dead, Then Where Does That Leave Everything Else? A Response to: Shirley Alexander's "Buying Essays: How to Make Sure Assessment Is Authentic"

    ERIC Educational Resources Information Center

    McQueen, Kelvin

    2015-01-01

    Professor Shirley Alexander is the Deputy Vice-Chancellor and Vice-President (Teaching, Learning & Equity) at the University of Technology, Sydney. On 12 November 2014, an article of hers appeared in "The Conversation": "Buying essays: how to make sure assessment is authentic." That article traverses, in an abbreviated way,…

  14. Prevention and Early Intervention: Individual Differences as Risk Factors for the Mental Health of Children. A Festschrift for Stella Chess and Alexander Thomas.

    ERIC Educational Resources Information Center

    Carey, William B., Ed.; McDevitt, Sean C., Ed.

    This collection of essays, in honor of child psychiatry pioneers Stella Chess and Alexander Thomas, focuses on their idea that important life outcomes are the product of ongoing interactions between a child's behavioral style and the complimentarity or lack of fit of the parenting environment. Following an introduction, the remaining chapters are:…

  15. The appearance of the artist to the people: the creativity, personality and malady of Alexander Ivanov (1806-58).

    PubMed

    Lerner, Vladimir; Witztum, Eliezer

    2005-02-01

    Alexander Ivanov was an outstanding Russian painter who lived in the middle of the nineteenth century, during the romantic period. He did not accept romanticism but instead tried to create his own original style, an ambitious combination of spiritual profundity and a manner of execution unparalleled in Western European art. Ivanov's intention and style are best reflected in his major work The Appearance of Christ to the People, a picture on which he worked for over 20 years. He painted more than 400 sketches of the picture while attempting to bring his masterpiece to perfection. At the end of his life Ivanov became disillusioned, renounced his strong religious conviction and became suspicious. This study examines the influence of his background, life story and personality on the creative process. From a diagnostic perspective, Ivanov's personality featured obsessive, narcissistic and schizoid traits. In his final years he suffered from a delusional disorder.

  16. Deficits in adult neurogenesis, contextual fear conditioning, and spatial learning in a Gfap mutant mouse model of Alexander disease.

    PubMed

    Hagemann, Tracy L; Paylor, Richard; Messing, Albee

    2013-11-20

    Glial fibrillary acidic protein (GFAP) is the major intermediate filament of mature astrocytes in the mammalian CNS. Dominant gain of function mutations in GFAP lead to the fatal neurodegenerative disorder, Alexander disease (AxD), which is characterized by cytoplasmic protein aggregates known as Rosenthal fibers along with variable degrees of leukodystrophy and intellectual disability. The mechanisms by which mutant GFAP leads to these pleiotropic effects are unknown. In addition to astrocytes, GFAP is also expressed in other cell types, particularly neural stem cells that form the reservoir supporting adult neurogenesis in the hippocampal dentate gyrus and subventricular zone of the lateral ventricles. Here, we show that mouse models of AxD exhibit significant pathology in GFAP-positive radial glia-like cells in the dentate gyrus, and suffer from deficits in adult neurogenesis. In addition, they display impairments in contextual learning and spatial memory. This is the first demonstration of cognitive phenotypes in a model of primary astrocyte disease.

  17. James Sowerby: meteorites and his meteoritic sword made for the Emperor of Russia, Alexander I, in 1814

    PubMed Central

    Henderson, Paul

    2013-01-01

    James Sowerby included meteorites in his publications of British and exotic natural history and so raised interest in their nature and origins at a time of much debate and involving the President of the Royal Society, Sir Joseph Banks. The celebrations over the defeat of France in 1814 prompted Sowerby to make a sword from the Cape of Good Hope iron meteorite to present to the Russian Emperor, Alexander I, at the time of his state visit to London in June 1814 and in recognition of his achievements in bringing peace to Europe. The story of its attempted presentation, its final reception and the following response, including publications, all helped to increase interest in meteorites and their properties. The rediscovery of the sword after a lengthy disappearance probably brings an unusual saga to a fitting close.

  18. Map of glacial limits and possible refugia in the southern Alexander Archipelago, Alaska, during the late Wisconsin glaciation

    USGS Publications Warehouse

    Carrara, Paul E.; Ager, Thomas A.; Baichtal, James F.; VanSistine, D. Paco

    2003-01-01

    During the late Wisconsin glaciation (circa 26,000-13,000 carbon-14 yr BP) the Cordilleran glacier complex formed vast ice fields and large glaciers along the crest of the Coast Mountains. As these glaciers flowed west to the Pacific Ocean, they were joined by local glaciers originating on the higher reaches of the Alexander Archipelago (Mann and Hamiltion, 1995). This extensive volume of ice was channeled into deep troughs (present-day fiords) that formed major outlet glaciers, such as the glaciers that occupied Chatham Strait and Dixon Entrance. In several places along the coast, deep glacially scoured submarine troughs indicate that glaciers reached to the edge of the continental shelf. For instance, the glacier that extended into the Dixon Entrance trough is known to have extended to the edge of the continental shelf. Its retreat began sometime after 16,000-15,000 carbon-14 yr BP (Barrie and Conway, 1999).

  19. The evolution of ultrahigh carbon steels - from the Great Pyramids, to Alexander the Great, to Y2K

    SciTech Connect

    Wadsworth, J

    1999-10-01

    Hypereutectoid steels containing between about 1 and 2.1 wt%C, and now known as ultrahigh carbon steels (UHCS), have both a rich history (dating back to the time of Alexander the Great, i.e. {approximately} 300 BC) and an interesting, recent, technological period of development (from 1975 to the present). The connections between the modern UHCS and their ancient counterparts, and in particular Damascus steels, have received considerable attention. In addition to monolithic products, UHCS have also been used in both ancient and modern times in laminated composites. In the present paper, a summary of the modern development of UHCS and UHCS-containing laminates is given, and parallels are drawn with ancient materials. Also, ancient laminated composites containing other steels are described; controversial issues and a possible solution related to the age of such a laminate found in the Great Pyramid of Gizeh are discussed.

  20. A double commutant theorem for Murray-von Neumann algebras.

    PubMed

    Liu, Zhe

    2012-05-15

    Murray-von Neumann algebras are algebras of operators affiliated with finite von Neumann algebras. In this article, we study commutativity and affiliation of self-adjoint operators (possibly unbounded). We show that a maximal abelian self-adjoint subalgebra A of the Murray-von Neumann algebra A(f)(R) associated with a finite von Neumann algebra R is the Murray-von Neumann algebra A(f)(A(0)), where A(0) is a maximal abelian self-adjoint subalgebra of R and, in addition, A(0) is A Π R. We also prove that the Murray-von Neumann algebra A(f)(C) with C the center of R is the center of the Murray-von Neumann algebra A(f)(R). Von Neumann's celebrated double commutant theorem characterizes von Neumann algebras R as those for which R'' = R, where R', the commutant of R, is the set of bounded operators on the Hilbert space that commute with all operators in R. At the end of this article, we present a double commutant theorem for Murray-von Neumann algebras.

  1. Non-Euclidean Space, Movement and Astronomy in Modern Art: Alexander Calder's Mobiles and Ben Nicholson's Reliefs

    NASA Astrophysics Data System (ADS)

    Malloy, Vanja

    2013-09-01

    John Keats once wrote that `there is no such thing as time and space' rather, believing that time and space are mental constructs that are subject to a variety of forms and as diverse as the human mind. In the 1920s through the 1930s, modern physics in many ways supported this idea through the various philosophical writings on the Theory of General Relativity to the masses by scientists such as Arthur Eddington and Albert Einstein. These new concepts of modern physics fundamentally changed our understanding of time and space and had substantial philosophical implications, which were absorbed by modern artists resulting in the 1936 Dimensionist Manifesto. Seeking to internalize the developments of modern science within modern art, this manifesto was widely endorsed by the most prominent figures of the avant-garde such as Marcel Duchamp, Jean Arp, Naum Gabo, Joan Miró, László Moholy-Nagy, Wassily Kandinsky and Alexander Calder. Of particular interest to this manifesto was the new concept of the fourth-dimension, which in many ways revolutionized the arts. Importantly, its interpretation varied widely in the artistic community, ranging from a purely physical four-dimensional space, to a kinetic concept of space in which space and time are linked, to a metaphysical interest in a space that exists beyond the material realm. The impact of modern science and astronomy on avant-garde art is currently a bourgeoning area of research with considerable implications to our rethinking of substantial artistic figures of this era. Through a case study of Alexander Calder's Mobiles and Ben Nicholson's Reliefs, this paper explores how these artworks were informed by an interest in modern science.

  2. Horizontal pendulum development and the legacy of Ernst von Rebeur-Paschwitz

    NASA Astrophysics Data System (ADS)

    Fréchet, Julien; Rivera, Luis

    2012-04-01

    Horizontal pendulum development was paramount in the birth of modern instrumental seismology and solid-earth tide study. This paper presents a revised history starting in the first part of the nineteenth century and culminating with Rebeur-Paschwitz's masterpiece in its latter part. The first stage began with the invention of the horizontal pendulum by Lorenz Hengler in 1832. He was followed by several, mostly independent, inventors during the three decades from the 1850s to the 1870s, in particular Friedrich Zöllner in 1869-1872 who popularized this instrument. With the exception of an instrument designed by Alexander Gerard in 1851, all these preliminary pendulums were suspended with two wires. Slightly different forms of horizontal pendulums were invented in Japan by James Ewing and Thomas Gray in the early 1880s, based on bracket or conical suspensions. The merit of demonstrating the outstanding potential of high-sensitivity horizontal pendulums completely relies on the work of Ernst von Rebeur-Paschwitz between 1886 and 1895. He successively developed three models of pendulums, in collaboration with three different manufacturers: the Fecker pendulum in 1886, the Repsold pendulum in 1888, from which six copies were produced, and finally, the Stückrath two-component model in 1894, built in three copies. Based on the scrutiny of a large number of previously unexploited archives, the detailed chronology of Rebeur-Paschwitz's achievements is presented. Archive, and in situ explorations allowed us to discover five out of the six original copies of the first Rebeur-Paschwitz's Repsold pendulum previously unknown or thought to be lost.

  3. From the classical to the generalized von Karman and Marguerre-von Karman equations

    NASA Astrophysics Data System (ADS)

    Ciarlet, Philippe G.; Gratie, Liliana

    2006-06-01

    In this work, we describe and analyze two models that were recently proposed for modeling generalized von Karman plates and generalized Marguerre-von Karman shallow shells.First, we briefly review the "classical" von Karman and Marguerre-von Karman equations, their physical meaning, and their mathematical justification. We then consider the more general situation where only a portion of the lateral face of a nonlinearly elastic plate or shallow shell is subjected to boundary conditions of von Karman type, while the remaining portion is free. Using techniques from formal asymptotic analysis, we obtain in each case a two-dimensional boundary value problem that is analogous to, but is more general than, the classical equations.In particular, it is remarkable that the boundary conditions for the Airy function can still be determined on the entire boundary of the nonlinearly elastic plate or shallow shell solely from the data.Following recent joint works, we then reduce these more general equations to a single "cubic" operator equation, which generalizes an equation introduced by Berger and Fife, and whose sole unknown is the vertical displacement of the shell. We next adapt an elegant compactness method due to Lions for establishing the existence of a solution to this operator equation.

  4. [Molecular biology of von Willebrand disease].

    PubMed

    Melo-Nava, Brenda; Peñaloza, Rosenda

    2007-01-01

    Von Willebrand Factor (VWF) is a large multimeric glycoprotein expressed in the megakaryocytes and endothelial cells of all vertebrates. It participates fundamentally in the primary and secondary hemostasis because it induces the adhesion of platelets to vascular subendothelium and promotes aggregation of platelets when blood vessels and capillaries are damaged. In addition, VWF links to factor VIII which avoids its proteolysis. The deficiency or the inadequate synthesis of the VWF causes von Willebrand disease (VWD), which is the most common hereditary bleeding disorder in humans principally from mucous and cutaneous sites. VWD is difficult to detect with accuracy due to interrelation among VWF with different components of hemostasis, although it is performed by different tests of haemostatic system, and the basic mechanisms in VWD are herein emphasized. The diagnosis of VWD is difficult due to the heterogeneous manifestation of the disease, which also complicates its classification. This article focuses on the molecular aspects of the disease and discusses their possible clinical implications.

  5. Vascular Manifestations of von Recklinghausen's Disease

    PubMed Central

    Fye, Kenneth H.; Jacobs, Richard P.; Roe, Robert L.

    1975-01-01

    A casual relationship between von Recklinghausen's disease, or neurofibromatosis, and arteriolar abnormalities has been reported in the European literature. A patient was seen who had biopsy-proved neurofibromatosis and renovascular hypertension and retroperitoneal bleeding. An arteriographic study showed multiple small aneurysms throughout the coeliac axis, the superior mesenteric artery and in several small intrarenal vessels. Renal vein renin levels were elevated particularly in the right renal vein, supporting the diagnosis of renovascular hypertension. Both the aneurysms seen in angiographic studies and the retroperitoneal hemorrhage are probably vascular manifestations of von Recklinghausen's disease. Support for this conclusion is enhanced by the absence of clinical, laboratory or histologic data supporting the only tenable differential diagnosis, periarteritis nodosa. ImagesFigure 1.Figure 2.Figure 3.Figure 4. PMID:803743

  6. Management of the von Roos operator

    NASA Astrophysics Data System (ADS)

    Molinar-Tabares, Martin; Castro-Arce, Lamberto; Figueroa-Navarro, Carlos; Campos-Garcia, Julio

    When an electron is inside a semiconductor medium its effective mass rises from the shielding of the crystalline structure. When we have a semiconductor with a constant concentration the effective mass has a fixed value, and in this case, it can be easy to solve the Schrodinger equation of the particle, but if the concentration varies spatially, the effective mass will no longer constant and the solution can be difficult to find. The general form of the kinetic energy operator for a particle with variable mass is proposed for von Roos, this operator is characterized by some parameters whose values are subjected to a restriction. From a numerical solution of the Schrodinger equation we analyze the energies of an electron with position-dependent effective mass working with some values of the parameter of the von Roos operator. We acknowledge the support of SNI CONACYT.

  7. Herstellung von Chitosan und einige Anwendungen

    NASA Astrophysics Data System (ADS)

    Struszczyk, Marcin Henryk

    2001-05-01

    1. Die Deacetylierung von crabshell - Chitosan führte gleichzeitig zu einem drastischen Abfall der mittleren viscosimetrischen Molmasse ( Mv), insbesondere wenn die Temperatur und die Konzentration an NaOH erhöht werden. Diese Parameter beeinflussten jedoch nicht den Grad der Deacetylierung (DD). Wichtig ist jedoch die Quelle des Ausgangsmaterials: Chitin aus Pandalus borealis ist ein guter Rohstoff für die Herstellung von Chitosan mit niedrigem DD und gleichzeitig hoher mittlerer Mv, während Krill-Chitin (Euphausia superba) ein gutes Ausgangsmaterial zur Herstellung von Chitosan mit hohem DD und niedrigem Mv ist. Chitosan, das aus Insekten (Calliphora erythrocephala), unter milden Bedingungen (Temperatur: 100°C, NaOH-Konzentration: 40 %, Zeit: 1-2h ) hergestellt wurde, hatte die gleichen Eigenschaften hinsichtlich DD und Mv wie das aus Krill hergestellte Chitosan. Der Bedarf an Zeit, Energie und NaOH ist für die Herstellung von Insekten-Chitosan geringer als für crabshell-Chitosan vergleichbare Resultaten für DD und Mv. 2. Chitosan wurde durch den Schimmelpilz Aspergillus fumigatus zu Chitooligomeren fermentiert. Die Ausbeute beträgt 25%. Die Chitooligomere wurden mit Hilfe von HPLC und MALDI-TOF-Massenspektrmetrie identifiziert. Die Fermentationsmischung fördert die Immunität von Pflanzen gegen Bakterien und Virusinfektion. Die Zunahme der Immunität schwankt jedoch je nach System Pflanze-Pathogen. Die Fermentation von Chitosan durch Aspergillus fumigatus könnte eine schnelle und billige Methode zur Herstellung von Chitooligomeren mit guter Reinheit und Ausbeute sein. Eine partiell aufgereinigte Fermentationsmischung dieser Art könnte in der Landwirtschaft als Pathogeninhibitor genutzt werden. Durch kontrollierte Fermentation, die Chitooligomere in definierter Zusammensetzung (d.h. definierter Verteilung des Depolymerisationsgrades) liefert, könnte man zu Mischungen kommen, die für die jeweilige Anwendung eine optimale Bioaktivität besitzen. 3

  8. Verbesserung der Symmetrie von Hirnaufnahmen entlang der Sagittalebene

    NASA Astrophysics Data System (ADS)

    Ens, Konstantin; Wenzel, Fabian; Fischer, Bernd

    Die lokale Symmetrie von Hirnscans entlang der Sagittalebene zu ermitteln und zu modizifieren, ist für eine Reihe neurologischer Anwendungen interessant. Beispielsweise kann der voxelweise Vergleich von rechter und linker Hirnhälfte nur dann Aufschluss über die Lokalisierung von Läsionen geben, wenn durch Transformation ein Hirnscan eine möglichst hohe Symmetrie aufweist. Ein weiteres Anwendungsgebiet ist die Visualisierung von medialen Hirnschnitten, für die die Trennfläche beider Hirnhälfte möglichst eben sein sollte. Diese Arbeit stellt die Entwicklung eines Verfahrens vor, mit dessen Hilfe die Symmetrie von Hirnaufnahmen entlang der Sagittalebene verbessert werden kann. Dies geschieht unter Verwendung von aktiven Konturen, die mit Hilfe einer neuartigen Kostenfunktion gesteuert werden. Experimente am Ende der Arbeit mit strukturellen Kernspinaufnahmen demonstrieren die Leistungsfähigkeit des Verfahrens.

  9. Portrait of Dr. Von Braun with Walt Disney, 1954.

    NASA Technical Reports Server (NTRS)

    1954-01-01

    Marshall Center Director Dr. Wernher Von Braun is pictured with Walt Disney during a visit to the Marshall Space Flight Center in 1954. In the 1950s, Dr. Von Braun while working in California on the Saturn project, also worked with Disney studios as a technical director in making three films about Space Exploration for television. Disney's tour of Marshall in 1965 was Von Braun's hope for a renewed public interest in the future of the Space Program at NASA.

  10. Dr. von Braun and Army Ballistics Missile Agency (ABMA) Group

    NASA Technical Reports Server (NTRS)

    1959-01-01

    This photograph of Dr. von Braun, shown here to the left of General Bruce Medaris, was taken in the fall of 1959, immediately prior to Medaris' retirement from the Army. At the time, von Braun and his associates worked for the Army Ballistics Missile Agency in Huntsville, Alabama. Those in the photograph have been identified as Ernst Stuhlinger, Frederick von Saurma, Fritz Mueller, Hermarn Weidner, E.W. Neubert (partially hidden), W.A. Mrazek, Karl Heimburg, Arthur Rudolph, Otto Hoberg, von Braun, Oswald Lange, Medaris, Helmut Hoelzer, Hans Maus, E.D. Geissler, Hans Heuter, and George Constan.

  11. PT2385 for the Treatment of Von Hippel-Lindau Disease-Associated Clear Cell Renal Cell Carcinoma

    ClinicalTrials.gov

    2017-04-04

    VHL Gene Mutation; VHL; VHL Syndrome; VHL Gene Inactivation; Von Hippel; Von Hippel-Lindau Disease; Von Hippel's Disease; Von Hippel-Lindau Syndrome, Modifiers of; Clear Cell Renal Cell Carcinoma; Clear Cell RCC; ccRCC

  12. The Cannery Formation--Devonian to Early Permian arc-marginal deposits within the Alexander Terrane, Southeastern Alaska

    USGS Publications Warehouse

    Karl, Susan M.; Layer, Paul W.; Harris, Anita G.; Haeussler, Peter J.; Murchey, Benita L.

    2011-01-01

    cherts on both Admiralty and Kupreanof Islands contain radiolarians as young as Permian, the age of the Cannery Formation is herein extended to Late Devonian through early Permian, to include the early Permian rocks exposed in its type locality. The Cannery Formation is folded and faulted, and its stratigraphic thickness is unknown but inferred to be several hundred meters. The Cannery Formation represents an extended period of marine deposition in moderately deep water, with slow rates of deposition and limited clastic input during Devonian through Pennsylvanian time and increasing argillaceous, volcaniclastic, and bioclastic input during the Permian. The Cannery Formation comprises upper Paleozoic rocks in the Alexander terrane of southeastern Alaska. In the pre-Permian upper Paleozoic, the tectonic setting of the Alexander terrane consisted of two or more evolved oceanic arcs. The lower Permian section is represented by a distinctive suite of rocks in the Alexander terrane, which includes sedimentary and volcanic rocks containing early Permian fossils, metamorphosed rocks with early Permian cooling ages, and intrusive rocks with early Permian cooling ages, that form discrete northwest-trending belts. After restoration of 180 km of dextral displacement of the Chilkat-Chichagof block on the Chatham Strait Fault, these belts consist, from northeast to southwest, of (1) bedded chert, siliceous argillite, volcaniclastic turbidites, pillow basalt, and limestone of the Cannery Formation and the Porcupine Slate of Gilbert and others (1987); (2) greenschist-facies Paleozoic metasedimentary and metavolcanic rocks that have Permian cooling ages; (3) silty limestone and calcareous argillite interbedded with pillow basalt and volcaniclastic rocks of the Halleck Formation and the William Henry Bay area; and (4) intermediate-composition and syenitic plutons. These belts correspond to components of an accretionary complex, contemporary metamorphic rocks, forearc-basin deposits,

  13. Approximating incompatible von Neumann measurements simultaneously

    SciTech Connect

    Heinosaari, Teiko; Jivulescu, Maria Anastasia; Reitzner, Daniel; Ziman, Mario

    2010-09-15

    We study the problem of performing orthogonal qubit measurements simultaneously. Since these measurements are incompatible, one has to accept additional imprecision. An optimal joint measurement is the one with the least possible imprecision. All earlier considerations of this problem have concerned only joint measurability of observables, while in this work we also take into account conditional state transformations (i.e., instruments). We characterize the optimal joint instrument for two orthogonal von Neumann instruments as being the Lueders instrument of the optimal joint observable.

  14. [Albrecht von Haller. An illustrious ancestor].

    PubMed

    Peiper, H-J

    2008-05-01

    Albrecht von Haller (1708-1777) was one of the most famous and important men of the eighteenth century. His achievements make him comparable with Lessing and Newton. In Blumenbach's opinion he was one of the enlightenment's greatest thinkers in both versatility and depth. He contributed significantly to developments in medicine, physiology, botany, pharmacology, theology, literature, editing, chronicles, biography, geography, and during his later years in Switzerland jurisprudence and agrarian reform. On the occasion of the 300th anniversary of his birth, important scientific landmarks in his life are described, with special attention to his achievements in the fields of anatomy, physiology, surgery, and experimental research.

  15. Acquired von Willebrand syndrome: von Willebrand factor propeptide to von Willebrand factor antigen ratio predicts remission status

    PubMed Central

    Lee, Adrienne; Sinclair, Gary; Valentine, Karen; James, Paula

    2014-01-01

    We investigated a case of acquired von Willebrand syndrome (AVWS) secondary to a nonneutralizing anti-von Willebrand factor (VWF) antibody associated with an autoimmune disorder. At diagnosis, VWF activity (VWF:Act), antigen (VWF:Ag), multimers, and factor VIII coagulant activity were virtually absent. VWF propeptide (VWFpp) was elevated with an infinitely high VWFpp to VWF:Ag ratio (VWFpp:Ag) consistent with rapid VWF clearance. Immunosuppressive treatment resulted in phenotypic remission 1 with normalization of VWF/factor VIII levels and multimer pattern. However, VWFpp:Ag remained elevated (∼2× normal), consistent with ongoing VWF clearance by the remaining anti-VWF antibody still present by enzyme-linked immunosorbent assay. This suggests that increased VWF secretion was compensating for the incomplete remission state. Relapse occurred when VWFpp:Ag was again infinitely high, with associated decreased VWFpp but unchanged anti-VWF titers; switching the balance to favor VWF clearance over secretion. Complete remission with undetectable anti-VWF occurred only when VWFpp:Ag was normal. This case of relapsing-remitting AVWS demonstrates the use of VWFpp:Ag for predicting remission status. PMID:24951428

  16. Group Theoretical Interpretation of von Neumann's Theorem on Composite Systems.

    ERIC Educational Resources Information Center

    Bergia, S.; And Others

    1979-01-01

    Shows that von Neumann's mathematical theorem on composite systems acquires a transparent physical meaning with reference to a suitable physical example; a composite system in a state of definite angular momentum. Gives an outline of the theorem, and the results are restated in Dirac's notation, thus generalizing von Neumann's results which were…

  17. Virtualized Optical Network (VON) for Future Internet and Applications

    NASA Astrophysics Data System (ADS)

    Jinno, Masahiko; Tsukishima, Yukio; Takara, Hidehiko; Kozicki, Bartlomiej; Sone, Yoshiaki; Sakano, Toshikazu

    A virtualized optical network (VON) is proposed as a key to implementing increased agility and flexibility into the future Internet and applications by providing any-to-any connectivity with the appropriate optical bandwidth at the appropriate time. The VON is enabled by introducing optical transparentization and optical fine granular grooming based on optical orthogonal frequency division multiplexing.

  18. Rare liver tumor: symptomatic giant von Meyenburg complex

    PubMed Central

    Singh, Yardesh; Cawich, Shamir O.; Ramjit, Chunilal; Naraynsingh, Vijay

    2016-01-01

    von Meyenburg complexes are hamartomas that arise from intra-hepatic bile ducts. Symptomatic lesions are uncommon and giant lesions are exceedingly rare. When encountered, they should be excised because there are reports of malignant change in large, symptomatic lesions. We report a case of a symptomatic giant von Meyenburg complex. PMID:28068648

  19. Victor or Villain? Wernher von Braun and the Space Race

    ERIC Educational Resources Information Center

    O'Brien, Jason L.; Sears, Christine E.

    2011-01-01

    Set during the Cold War and space race, this historical role-play focuses on Wernher von Braun's involvement in and culpability for the use of slave laborers to produce V-2 rockets for Nazi Germany. Students will grapple with two central questions. Should von Braun have been allowed to emigrate to the United States given his affiliation with the…

  20. Dr. von Braun Tries Out the Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Marshall Space Flight Center (MSFC) Director, Dr. von Braun, submerges after spending some time under water in the MSFC Neutral Buoyancy Simulator (NBS). Weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  1. Dr. von Braun Tries Out the Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Astronaut L. Gordon Cooper checks the neck ring of a space suit worn by Marshall Space Flight Center (MSFC) Director, Dr. von Braun before he submerges into the water of the MSFC Neutral Buoyancy Simulator (NBS). Wearing a pressurized suit and weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  2. Dr. von Braun Tries Out the Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Marshall Space Flight Center (MSFC) Director, Dr. von Braun, is shown leaving the suiting-up van wearing a pressure suit prepared for a tryout in the MSFC Neutral Buoyancy Simulator (NBS). Weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  3. 2012 ARPA-E Energy Innovation Summit Keynote Presentation (Frederick W. Smith, FedEx Corporation), with Introduction by Senator Lamar Alexander (TN)

    SciTech Connect

    Smith, Frederick W.

    2012-04-24

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. Following introduction by Senator Lamar Alexander of Tennessee, Frederick W. Smith, Chairman, President, and CEO of FedEx Corporation, gave the third keynote presentation of the day.

  4. 2012 ARPA-E Energy Innovation Summit Keynote Presentation (Frederick W. Smith, FedEx Corporation), with Introduction by Senator Lamar Alexander (TN)

    ScienceCinema

    Smith, Frederick W. (FedEx Corporation, Chairman, President and CEO)

    2016-07-12

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. Following introduction by Senator Lamar Alexander of Tennessee, Frederick W. Smith, Chairman, President, and CEO of FedEx Corporation, gave the third keynote presentation of the day.

  5. Using the Alexander Collection to measure the effects of climate change on the grasshoppers of the southern Rocky Mountains of Colorado

    NASA Astrophysics Data System (ADS)

    Nufio, C. R.; Bowers, D. M.; Guralnick, R. P.

    2007-12-01

    The current study utilizes the recently curated and databased Alexander Grasshopper Collection coupled with a new resurvey program to measure the effects of climate change on grasshoppers found along an elevational gradient in the southern Rocky Mountains of Colorado. The Alexander Collection is composed of approximately 19,000 pinned grasshoppers and a series of field data notebooks from a three year 1958-1960 survey project. During these survey years, Alexander processed over 65,000 grasshoppers from repeatedly sampled sites along an elevational gradient from Boulder (1530 m elev.) to Mt Evans (3900m elev.) in the Colorado Front Range. Data from 2006 shows that at mid-elevation sites grasshoppers are becoming adults 15-28 days earlier than they did nearly a half century ago. We found no changes in the time to reach adulthood at the high elevation sites. Preliminary data from 2007 (a year with milder spring temperatures) suggests that unlike the dramatic patterns documented in 2006, that the time to reach adulthood for grasshoppers at low and high elevation sites was not much different than it was 50 years ago. In 2007, several grasshopper species at mid-elevation did become adults earlier than they had a half century ago.

  6. Wernher von Braun and Saturn IB on Launch Pad

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Dr. Wernher von Braun stands in front of a Saturn IB launch vehicle at Kennedy Space Flight Center. Dr. von Braun led a team of German rocket scientists, called the Rocket Team, to the United States, first to Fort Bliss/White Sands, later being transferred to the Army Ballistic Missile Agency at Redstone Arsenal in Huntsville, Alabama. They were further transferred to the newly established NASA/Marshall Space Flight Center (MSFC) in Huntsville, Alabama in 1960, and Dr. von Braun became the first Center Director. Under von Braun's direction, MSFC developed the Mercury-Redstone, which put the first American in space; and later the Saturn rockets, Saturn I, Saturn IB, and Saturn V. The Saturn V launch vehicle put the first human on the surface of the Moon, and a modified Saturn V vehicle placed Skylab, the first United States' experimental space station, into Earth orbit. Dr. von Braun was MSFC Director from July 1960 to February 1970.

  7. Listening to the whispers of matter through Arabic hermeticism: new studies on The Book of the Treasure of Alexander.

    PubMed

    Alfonso-Goldfarb, Ana Maria; Jubran, Safa Abou Chahla

    2008-07-01

    The Jabirian Corpus refers to the K. Thahirat Al-'Iskandar, "The Book of the Treasure of Alexander" (hereafter BTA), as one of several forgeries suggesting that alchemical secrets were hidden in inscriptions in various places. The book was neglected until 1926, when Julius Ruska discussed it in his work on the Emerald Tablet, placing the BTA within the literature related to the development of Arabic alchemy. His preliminary study became an essential reference and encouraged many scholars to work on the BTA in the following decades. Some years ago, we completed the first translation of the BTA into a Western language. The work was based on the acephalous Escorial manuscript, which we identified as a fourteenth-century copy of the BTA. This manuscript is peculiar, as part of it is encoded. After finishing our translation, we started to establish the text of the BTA. At present, the text is in process of fixation--to be followed by textual criticism--and has been the main focus of a thorough study of ours on medieval hermeticism and alchemy. A sample of the work currently in progress is presented in this paper: an analysis of the variations between different manuscripts along with a study and English translation of its alchemical chapter.

  8. Prolonged weight-shift and altered spinal coordination during sit-to-stand in practitioners of the Alexander Technique

    PubMed Central

    Cacciatore, Timothy W; Gurfinkel, Victor S; Horak, Fay B; Day, Brian L

    2011-01-01

    The Alexander Technique (AT) is used to improve postural and movement coordination and has been reported to be clinically beneficial, however its effect on movement coordination is not well-characterized. In this study we examined the sit-to-stand (STS) movement by comparing coordination (phasing, weight-shift and spinal movement) between AT teachers (n=15) and matched control subjects (n=14). We found AT teachers had a longer weight-shift (p<0.001) and shorter momentum transfer phase (p=0.01), than control subjects. AT teachers also increased vertical foot force monotonically, rather than unweighting the feet prior to seat-off, suggesting they generate less forward momentum with hip flexors. The prolonged weight-shift of AT teachers occurred over a greater range of trunk inclination, such that their weight shifted continuously onto the feet while bringing the body mass forward. Finally, AT teachers had greatly reduced spinal bending during STS (cervical, p<0.001; thoracic, p<0.001; lumbar, p<0.05). We hypothesize that the low hip joint stiffness and adaptive axial postural tone previously reported in AT teachers underlies this novel “continuous” STS strategy by facilitating eccentric contractions during weight-shift. PMID:21782443

  9. Alexander Technique Training Coupled With an Integrative Model of Behavioral Prediction in Teachers With Low Back Pain

    PubMed Central

    Kamalikhah, Tahereh; Morowatisharifabad, Mohammad Ali; Rezaei-Moghaddam, Farid; Ghasemi, Mohammad; Gholami-Fesharaki, Mohammad; Goklani, Salma

    2016-01-01

    Background Individuals suffering from chronic low back pain (CLBP) experience major physical, social, and occupational disruptions. Strong evidence confirms the effectiveness of Alexander technique (AT) training for CLBP. Objectives The present study applied an integrative model (IM) of behavioral prediction for improvement of AT training. Methods This was a quasi-experimental study of female teachers with nonspecific LBP in southern Tehran in 2014. Group A contained 42 subjects and group B had 35 subjects. In group A, AT lessons were designed based on IM constructs, while in group B, AT lessons only were taught. The validity and reliability of the AT questionnaire were confirmed using content validity (CVR 0.91, CVI 0.96) and Cronbach’s α (0.80). The IM constructs of both groups were measured after the completion of training. Statistical analysis used independent and paired samples t-tests and the univariate generalized linear model (GLM). Results Significant differences were recorded before and after intervention (P < 0.001) for the model constructs of intention, perceived risk, direct attitude, behavioral beliefs, and knowledge in both groups. Direct attitude and behavioral beliefs in group A were higher than in group B after the intervention (P < 0.03). Conclusions The educational framework provided by IM for AT training improved attitude and behavioral beliefs that can facilitate the adoption of AT behavior and decreased CLBP. PMID:28144457

  10. Growing community: the impact of the Stephanie Alexander Kitchen Garden Program on the social and learning environment in primary schools.

    PubMed

    Block, Karen; Gibbs, Lisa; Staiger, Petra K; Gold, Lisa; Johnson, Britt; Macfarlane, Susie; Long, Caroline; Townsend, Mardie

    2012-08-01

    This article presents results from a mixed-method evaluation of a structured cooking and gardening program in Australian primary schools, focusing on program impacts on the social and learning environment of the school. In particular, we address the Stephanie Alexander Kitchen Garden Program objective of providing a pleasurable experience that has a positive impact on student engagement, social connections, and confidence within and beyond the school gates. Primary evidence for the research question came from qualitative data collected from students, parents, teachers, volunteers, school principals, and specialist staff through interviews, focus groups, and participant observations. This was supported by analyses of quantitative data on child quality of life, cooperative behaviors, teacher perceptions of the school environment, and school-level educational outcome and absenteeism data. Results showed that some of the program attributes valued most highly by study participants included increased student engagement and confidence, opportunities for experiential and integrated learning, teamwork, building social skills, and connections and links between schools and their communities. In this analysis, quantitative findings failed to support findings from the primary analysis. Limitations as well as benefits of a mixed-methods approach to evaluation of complex community interventions are discussed.

  11. Crossed aphasia in a dextral: a test of the Alexander-Annett theory of anomalous organization of brain function.

    PubMed

    Osmon, D C; Panos, J; Kautz, P; Gandhavadi, B

    1998-07-01

    A case of crossed aphasia is presented in a strongly right-handed 77-year-old white female without history of familial sinistrality or prior neurological illness. She developed a right middle cerebral artery infarction documented by CT and accompanied by obvious clinical signs of a conduction aphasia with some resolution but continuing obvious language defect after 9 weeks in rehabilitation. Comprehensive neuropsychological and aphasia testing suggested anomalous lateralization of phonologic-output aspects of language, emotional prosody, motor planning and body schema modules with usual lateralization of lexical-semantic aspects of language and visuo-spatial functions. Experimental validation of the uncrossed lexical-semantic aspects of language using tachistoscope methods found support for the Alexander-Annett theory that different aspects of language can be dissociated in their lateralization. The subject had difficulty identifying a semantic associate of a picture presented to the left visual field (7 errors out of 10) relative to right visual field presentation (2 errors out of 10). Bilateral free naming errors (6 and 5 errors in the left and right visual fields, respectively) occurred consistent with the aphasic presentation, suggesting phonologic-output dysfunction from the right cerebral vascular accident. Implications of the results for aphasia classification are discussed.

  12. Report on von Willebrand Disease in Malaysia

    PubMed Central

    Periayah, Mercy Halleluyah; Halim, Ahmad Sukari; Saad, Arman Zaharil Mat; Yaacob, Nik Soriani; Karim, Faraizah Abdul

    2016-01-01

    BACKGROUND: Von Willebrand disease (vWD) is an inherited hemostatic disorder that affects the hemostasis pathway. The worldwide prevalence of vWD is estimated to be 1% of the general population but only 0.002% in Malaysia. AIM: Our present paper has been written to disclose the statistical counts on the number of vWD cases reported from 2011 to 2013. MATERIAL AND METHODS: This article is based on sociodemographic data, diagnoses and laboratory findings of vWD in Malaysia. A total of 92 patients were reported to have vWD in Malaysia from 2011 to 2013. RESULTS: Sociodemographic-analysis revealed that 60% were females, 63% were of the Malay ethnicity, 41.3% were in the 19-44 year old age group and 15.2% were from Sabah, with the East region having the highest registered number of vWD cases. In Malaysia, most patients are predominately affected by vWD type 1 (77.2%). Factor 8, von Willebrand factor: Antigen and vWF: Collagen-Binding was the strongest determinants in the laboratory profiles of vWD. CONCLUSION: This report has been done with great interest to provide an immense contribution from Malaysia, by revealing the statistical counts on vWD from 2011-2013. PMID:27275342

  13. Molecular diagnosis of von Willebrand disease.

    PubMed

    Baronciani, L; Goodeve, A; Peyvandi, F

    2017-03-01

    The role of molecular characterization in the diagnosis of von Willebrand disease (VWD) is not essential if the patients have been extensively investigated using phenotypic analysis. On the other hand, if some of these phenotype assays are not available, the identification of the mutation causing the disease could be crucial for an accurate diagnosis. Nevertheless, there are several reasons for performing molecular analysis in patients phenotypically well characterized, e.g. to identify the mutation causing VWD can be useful for patients and their family members when prenatal diagnosis is required (type 3 or severe type 2). In this manuscript, we report the techniques used for the molecular characterization of suspected VWD patients. We describe the use of online von Willebrand factor database and online single nucleotide variation databases, the former to verify whether a candidate mutation has been previously identified in other VWD patients and the latter to ascertain whether a putative mutation has been reported earlier in healthy individuals. We listed the available in silico analysis tools, to determine the predicted pathogenicity of a sequence variant and to establish its possible negative effect on the normal splicing process. We also report the strategy that can be used to identify VWD type 2 patients' mutations in subjects who have been fully characterized using the phenotype assays.

  14. Approximate von Neumann entropy for directed graphs.

    PubMed

    Ye, Cheng; Wilson, Richard C; Comin, César H; Costa, Luciano da F; Hancock, Edwin R

    2014-05-01

    In this paper, we develop an entropy measure for assessing the structural complexity of directed graphs. Although there are many existing alternative measures for quantifying the structural properties of undirected graphs, there are relatively few corresponding measures for directed graphs. To fill this gap in the literature, we explore an alternative technique that is applicable to directed graphs. We commence by using Chung's generalization of the Laplacian of a directed graph to extend the computation of von Neumann entropy from undirected to directed graphs. We provide a simplified form of the entropy which can be expressed in terms of simple node in-degree and out-degree statistics. Moreover, we find approximate forms of the von Neumann entropy that apply to both weakly and strongly directed graphs, and that can be used to characterize network structure. We illustrate the usefulness of these simplified entropy forms defined in this paper on both artificial and real-world data sets, including structures from protein databases and high energy physics theory citation networks.

  15. Two novel anti-von Willebrand factor monoclonal antibodies.

    PubMed

    Spadafora-Ferreira, M; Lopes, A A; Coelho, V; Guilherme, L; Kalil, J

    2000-01-15

    Von Willebrand Factor is a multimer produced by endothelial cells and megakaryocytes, being stored in intracellular organelles, such as the Weibel-Palade bodies and alpha-granules in endothelial cells and platelets, respectively. This molecule acts as a carrier protein for factor VIIIc, involved in the intrinsic pathway of blood coagulation maintaining its stability in circulation. Von Willebrand Factor also plays an important role in platelet aggregation and adhesion to injured vessel wall. It interacts with platelets through two distinct glycoproteins, GPIb and GPIIb/IIIa. We raised two monoclonal antibodies, ECA-3 and ECA-4, against human umbilical vascular endothelial cells that recognize and immunoprecipitate von Willebrand Factor. Interestingly, ECA-4 monoclonal antibody is able to completely inhibit platelet agglutination induced by ristocetin, suggesting that it binds to von Willebrand Factor close to platelet GPIb binding site. The use of monoclonal antibodies to identify von Willebrand Factor binding regions to factor VIII or platelets has been reported by others. In pulmonary hypertension, abnormalities have been detected on the multimeric structure of the molecule as well as on its proteolytic fragments, by using monoclonal antibodies. Moreover, monoclonal antibodies raised against specific regions of von Willebrand Factor molecule may allow studies of functional abnormalities of this protein in inherited and acquired disorders like subtypes of von Willebrand's disease.

  16. [Von Willebrand disease in the Netherlands: the WiN study].

    PubMed

    Sanders, Yvonne V; de Wee, Eva M; Meijer, Karina; Eikenboom, J; van der Bom, Jeroen G; Fijnvandraat, C J Karin; Laros-van Gorkom, Britta A P; Cnossen, Marjon H; Mauser-Bunschoten, Evelien P; Leebeek, Frank W G

    2014-01-01

    Von Willebrand disease is the most common inherited bleeding disorder and is characterised by mucocutaneous bleeding. Von Willebrand disease is caused by reduced levels or reduced function of von Willebrand factor. Depending on the cause, von Willebrand disease is distinguished into various types with their own characteristics and treatment options. The frequency and severity of bleeding in patients with von Willebrand disease is strongly determined by von Willebrand factor levels, factor VIII levels and the type of von Willebrand disease. Eighty-five percent of all adult females with von Willebrand disease reports menorrhagia. A high percentage have postpartum excessive blood loss (37% of all deliveries). The quality of life is reduced in patients with von Willebrand disease. Patients with von Willebrand disease have a reduced risk of arterial thrombosis such as a myocardial or cerebral infarction.

  17. Interactions of von Willebrand factor and ADAMTS13 in von Willebrand disease and thrombotic thrombocytopenic purpura.

    PubMed

    Budde, U; Schneppenheim, R

    2014-01-01

    The function of von Willebrand factor (VWF), a huge multimeric protein and a key factor in platelet dependent primary haemostasis, is regulated by its specific protease ADAMTS13. The ADAMTS13 dependent degradation of VWF to its proteolytic fragments can be visualized as a characteristic so-called triplet structure of individual VWF oligomers by multimer analysis. Lack of VWF high molecular weight multimers (VWF-HMWM) or their pathologically enhanced degradation underlies a particular type of von Willebrand disease, VWD type 2A with a significant bleeding tendency, and may also be observed in acquired von Willebrand syndrome due to cardiovascular disease. In these conditions multimer analysis is an obligatory and powerful tool for diagnosis of VWD. The opposite condition, the persistence of ultralarge VWF (UL-VWF) multimers may cause the microangiopathic life-threatening disorder thrombotic thrombocytopenic purpura (TTP). During the course of active TTP, UL-VWF is consumed in the hyaline thrombi formed in the microvasculature which will ultimately result in the loss of UL-VWF and VWF-HMWM. Therefore, VWF multimer analysis is not a valid tool to diagnose TTP in the active phase of disease but may be helpful for the diagnosis of TTP patients in remission.

  18. Quantenphysik Interferometrie von C70-Molekülen

    NASA Astrophysics Data System (ADS)

    Ziegler, Thomas

    2002-05-01

    Interferenzversuche mit Neutronen und schweren Atomen stellen kein großes Problem mehr dar, selbst die Welleneigenschaften von C60-und C70-Molekülen wurden bereits nachgewiesen. Allerdings stößt man bei der Realisation immer feinerer Gitter mit Gitterkonstanten von etwa 100 nm im Fall dieser Moleküle auf technische Probleme. Wissenschaftlern der Universität Wien ist es jüngst gelungen, ein so genanntes Talbot-Lau-Interferometer zu realisieren und die Welleneigenschaften von C70 mit einer bislang unerreichten Qualität nachzuweisen [1].

  19. Valence bond and von Neumann entanglement entropy in Heisenberg ladders.

    PubMed

    Kallin, Ann B; González, Iván; Hastings, Matthew B; Melko, Roger G

    2009-09-11

    We present a direct comparison of the recently proposed valence bond entanglement entropy and the von Neumann entanglement entropy on spin-1/2 Heisenberg systems using quantum Monte Carlo and density-matrix renormalization group simulations. For one-dimensional chains we show that the valence bond entropy can be either less or greater than the von Neumann entropy; hence, it cannot provide a bound on the latter. On ladder geometries, simulations with up to seven legs are sufficient to indicate that the von Neumann entropy in two dimensions obeys an area law, even though the valence bond entanglement entropy has a multiplicative logarithmic correction.

  20. Alexander Ya. Orolv - Well-Known Scientist and Recognized Organizer of Astronmoical Research. Little Known Facts of His Life

    NASA Astrophysics Data System (ADS)

    Yatskiv, Ya. S.; Vavilova, I. B.; Korsun', A. A.

    Alexander Ya. Orlov is a well-known astronomer and geophysicist as well as a worldrecognized organizer of scientific research in Russia, the USSR, and Ukraine. Orlov has formulated his main scientific ideas during the Odesa's period of life. He studied a tidal deformation of the Earth and its polar motion using the gravity and latitude observations. He has proposed new defenitions of a mean pole and a mean latitude, as wel as a new method for determing the Earth pole coordinates. To the end of 1940-ties, the Orlov's scientific ideas were implemented and stimulated a development of a research field, which is now called as Astrogeodynamics or Space Geodynamics. Among the representatives of the Orlov's scientific school are about 20 Doctors of Sciences and more than 40 Candidates of Sciences, including the members of Academy of Sciences of Ukraine and other countries. Among them are N.Stoyko-Radilenko (France), J.Witkowski (Poland), V.Zhardetsky (Yugoslavia-Austria-USA), D.Pyaskovsky, Z.Aksent'eva, E.Lavrentieva, N.Popov, E.Fedorov and A.Korol in Ukraine. The deserved followers of the Orlov's scientific ideas were also I.Androsov, I.Dyukov, K.Mansurova, B.Novopashennyj, N.V.Zimmerman in Russia and M.Bursa (Chesh Republic), who worked with him, as well as his sons, A.A.Orlov and B.A. Orlov. The Orlov's life and scientific activity were fully described in many articles. For that reason in this paper we will focus on the little-known facts of the Orlov's scientific-organizational activity, for example, the Orlov's appointments as a director of observatories in Odesa, Poltava, m.Pip-Ivan, Pulkovo, and Kyiv; interesesting facts related to his membership in the Academies of Sciences of the USSR and Ukrainian SSR; organization of a large-scale program on the latitude observations and gravimetric survey. We describe briefly his life and his astrogeodynamic scientific school.

  1. Clinical aspects and pathology of Alexander disease, and morphological and functional alteration of astrocytes induced by GFAP mutation.

    PubMed

    Yoshida, Tomokatsu; Nakagawa, Masanori

    2012-08-01

    Alexander disease (AxD) is pathologically characterized by the presence of Rosenthal fibers (RF), which are made up of GFAP, αB-crystallin and heat shock protein 27, in the cytoplasm of perivascular and subpial astrocyte endfeet. Since GFAP mutation has been confirmed in reported cases of AxD, clinical or experimental research is being conducted on the relationship between GFAP mutation and the onset pathology as well as the clinical form. We conducted a nationwide survey and a clinical study, and classified AxD into three types: cerebral AxD (type 1), which primarily has an infantile onset with presence of seizures, psychomotor developmental retardation, macrocephaly, and abnormalities in the superior frontal cerebral white matter observed in a brain MRI; bulbospinal AxD (type 2), which primarily has an adult onset with presence of muscle weakness, hyperreflexia, bulbar or pseudobulbar symptoms, signal abnormalities, and atrophy observed in an MRI of the medulla oblongata and upper cervical spinal cord; and an intermediate form (type 3) which has the characteristics of both. A research on GFAP mutations and aggregate formation concluded that GFAP mutations decreased the solubility of GFAP. According to our cell model experiment, the formation of mutant GFAP aggravates depending on the site of the GFAP mutation. Furthermore, there is a possibility that polymorphism in the GFAP promoter gene regulates the degree to which GFAP is expressed; it may have an effect on clinical heterogeneity. Recent research using cell and animal models suggests that the pathology of AxD involves not only mere functional abnormalities in intermediate filaments but also functional abnormalities in astrocytes as well as in neurons. Clarification of the glia-neuron interactions will prove the disease to be very interesting.

  2. Hermann von Helmholtz and his students

    NASA Astrophysics Data System (ADS)

    Mulligan, Joseph F.

    1989-01-01

    During the years 1871-1888, when Hermann von Helmholtz was professor of physics at the University of Berlin, physicists from all over the world flocked to Berlin to study and do research with him. Among these were the German physicists Max Planck, Heinrich Kayser, Eugen Goldstein, Wilhelm Wien, and Heinrich Hertz, and Americans Henry Rowland, A. A. Michelson, and Michael Pupin. Examples of Helmholtz's scientific and personal interactions with these students and research associates show why he is justly considered the outstanding physics mentor of the 19th century. Both his ideas and his students played a major role in the development of physics in the late 19th and early 20th centuries.

  3. Von Economo neurons in the elephant brain.

    PubMed

    Hakeem, Atiya Y; Sherwood, Chet C; Bonar, Christopher J; Butti, Camilla; Hof, Patrick R; Allman, John M

    2009-02-01

    Von Economo neurons (VENs), previously found in humans, all of the great ape species, and four cetacean species, are also present in African and Indian elephants. The VENs in the elephant are primarily found in similar locations to those in the other species. They are most abundant in the frontoinsular cortex (area FI) and are also present at lower density in the anterior cingulate cortex. Additionally, they are found in a dorsolateral prefrontal area and less abundantly in the region of the frontal pole. The VEN morphology appears to have arisen independently in hominids, cetaceans, and elephants, and may reflect a specialization for the rapid transmission of crucial social information in very large brains.

  4. Johann Philipp von Wurzelbau (1651-1725)

    NASA Astrophysics Data System (ADS)

    Gaab, Hans

    During the turn of the 17th to the 18th century, Johann Philipp von Wurzelbau was the best-known astronomer in Nuremberg. He was a trained merchant, who busied himself in his free hours with astronomy. In the 1680s he became known for his accurate observations of lunar and solar eclipses. At the end of the 1680s he left his trade, and from 1691, he was completely occupied with astronomy. To that end, he constructed a small octagonal observing tower on the roof of his house at Spitzenberg 4. He took the measurement of the solar path and determined the geographical coordinates of Nuremberg. The calendar reform also played a major role in his life.

  5. Dr. von Braun at the Manufacturing and Engineering Laboratory

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Dr. von Braun, Director of the Marshall Space Flight Center, listens attentively to a briefing on the metal forming techniques by Dr. Mathias Siebel of the Manufacturing and Engineering Laboratory at MSFC on October 17, 1967.

  6. 33. HISTORIC VIEW OF WERNHER VON BRAUN LOOKS THROUGH THE ...

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

    33. HISTORIC VIEW OF WERNHER VON BRAUN LOOKS THROUGH THE PERISCOPE FROM THE CONTROL ROOM AT TEST STAND NO. 1, PEENEMUENDE. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  7. Fletcher and von Braun at Apollo 15 launch

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Recently appointed NASA Administrator Dr. James C. Fletcher, left, and Dr. Wernher von Braun, Deputy Associate Administrator for Planning, monitor Apollo 15 prelaunch activities in Firing Room 1 of the Launch Control Center and the Kennedy Space Center, Florida.

  8. Dr. Wernher Von Braun examines a ruby crystal.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (right), director of the Marshall Space Flight Center, and Dr. Eberhard Rees (left), deputy director, technical, examine a ruby crystal used in laser experiments in the Marshall Center's Space Sciences Laboratory.

  9. 7. Historic American Buildings Survey, Charles Von Urban, Photographer June ...

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

    7. Historic American Buildings Survey, Charles Von Urban, Photographer June 23, 1936, INTERIOR-PARLOR SHOWING FIREPLACE, WINDOWN TRIM, AND CORNICE. - George Fordham House, 329 Cherry Street, New York County, NY

  10. Physik gestern und heute Von der Metallstange zum Hochenergielaser

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2002-05-01

    Im Mai 1752 wurde in Marly bei Paris auf Anregung des amerikanischen Forschers und Politikers Benjamin Franklin erstmals die elektrische Natur des Blitzes nachgewiesen. Damals beschrieb Franklin auch eine technische Vorrichtung, die als Schutz von Gebäuden vor Blitzschlägen dienen sollte: den Blitzableiter. Diese aus heutiger Sicht scheinbar triviale Vorrichtung wurde aber keineswegs unmittelbar akzeptiert. Und bis heute ist die Forschung zum Schutz von Einrichtungen vor Blitzschlägen nicht abgeschlossen.

  11. Wernher von Braun with German Officers and Others

    NASA Technical Reports Server (NTRS)

    1942-01-01

    General Erich Fellgiebel, head of the German Army Information Service during World War II, congratulates members of the von Braun rocket team from Peenemunde for their October 3, 1942 A4 flight. Pictured front center is General Erich Fellgiebel. Shaking hands are General Walter Dornberger (left) and General Janssen, commanding officer of Peenemuende with Rudolph Hermarn to their right. Picture left to right in the back row are Wernher von Braun, Captain Stoelzel, Luftwaffe, and Dr. Gerhard Reisig.

  12. Gastrointestinal angiodysplasia and bleeding in von Willebrand disease.

    PubMed

    Franchini, M; Mannucci, P M

    2014-09-02

    Von Willebrand disease (VWD), the most common genetic bleeding disorder, is characterised by a quantitative or qualitative defect of von Willebrand factor (VWF). Patients with VWD suffer from mucocutaneous bleeding, of severity usually proportional to the degree of VWF defect. In particular, gastrointestinal bleeding associated with angiodysplasia is often a severe symptom of difficult management. This review focuses on the pathophysiology, diagnosis and treatment of VWD-associated gastrointestinal angiodysplasia and related bleeding.

  13. Management of Type 2B von Willebrand Disease during Pregnancy.

    PubMed

    McLaughlin, David; Kerr, Ron

    2017-01-01

    Type 2B von Willebrand disease is a rare bleeding condition resulting in thrombocytopenia and a reduction in large VWF multimers. It usually has an autosomal dominant pattern of inheritance. We report the management of a patient with type 2B von Willebrand disease, whose diagnosis was confirmed by demonstration of a R1306W mutation, through her first pregnancy. The patient's von Willebrand factor (VWF) antigen and VWF ristocetin cofactor levels rose throughout pregnancy, with an associated drop in the platelet count. The patient was successfully managed through labour to a surgical delivery with VWF concentrate, platelet transfusions and tranexamic acid. The patient delivered a male baby who was found to have inherited type 2B von Willebrand disease and had a significant cephalhaematoma at delivery. The baby was managed with VWF concentrate and platelet transfusions and made a full recovery. There is a lack of evidence to guide the best management of pregnant patients with type 2B von Willebrand disease. We adopted a pragmatic management plan, in keeping with other published case reports. To the best of our knowledge, this is the first case report in which the child was found to have inherited type 2B von Willebrand disease and encountered bleeding problems, making this case unique amongst the published literature.

  14. The Neotropical tanyderid Araucoderus gloriosus (Alexander) (Diptera, Tanyderidae), with description of the egg, larva and pupa, redescription of adults, and notes on natural history.

    PubMed

    Madriz, R Isaí; Courtney, Gregory W

    2016-08-30

    Larvae, pupae and adults of Araucoderus gloriosus (Alexander) were collected during fieldwork in Chilean Patagonia, December 2013 and January 2014. Eggs were obtained from females that oviposited in captivity. Association of all life stages is based on co-occurrence and rearing of individual larvae to adults. A diagnosis for the genus and species is provided. Descriptions of the egg, larva and pupa and redescriptions of the male and female are completed. Eggs of A. gloriosus are the first described for Tanyderidae. Natural history characteristics for this species, including microhabitat, copulatory behavior and oviposition, are discussed.

  15. Alexander Technique Lessons, Acupuncture Sessions or usual care for patients with chronic neck pain (ATLAS): study protocol for a randomised controlled trial

    PubMed Central

    2013-01-01

    Background Chronic neck pain is a common condition in the adult population. More research is needed to evaluate interventions aiming to facilitate beneficial long-term change. We propose to evaluate the effect of Alexander Technique lessons and acupuncture in a rigorously conducted pragmatic trial with an embedded qualitative study. Methods/Design We will recruit 500 patients who have been diagnosed with neck pain in primary care, who have continued to experience neck pain for at least three months with 28% minimum cut-off score on the Northwick Park Neck Pain Questionnaire (NPQ). We will exclude patients with serious underlying pathology, prior cervical spine surgery, history of psychosis, rheumatoid arthritis, ankylosing spondylitis, osteoporosis, haemophilia, cancer, HIV or hepatitis, or with alcohol or drug dependency currently or in the last 12 months, or actively pursuing compensation or with pending litigation. The York Trials Unit will randomly allocate participants using a secure computer-based system. We will use block randomisation with allocation to each intervention arm being unambiguously concealed from anyone who might subvert the randomisation process. Participants will be randomised in equal proportions to Alexander Technique lessons, acupuncture or usual care alone. Twenty 30-minute Alexander Technique lessons will be provided by teachers registered with the Society of Teachers of the Alexander Technique and twelve 50-minute sessions of acupuncture will be provided by acupuncturists registered with the British Acupuncture Council. All participants will continue to receive usual GP care. The primary outcome will be the NPQ at 12 months, with the secondary time point at 6 months, and an area-under-curve analysis will include 3, 6 and 12 month time-points. Adverse events will be documented. Potential intervention effect modifiers and mediators to be explored include: self-efficacy, stress management, and the incorporation of practitioner advice about

  16. von Willebrand factor expression in osteosarcoma metastasis.

    PubMed

    Eppert, Kolja; Wunder, Jay S; Aneliunas, Vicky; Kandel, Rita; Andrulis, Irene L

    2005-03-01

    A number of genes are implicated in the initiation and progression of osteosarcoma; however, cytogenetic and comparative genomic hybridization studies indicate the involvement of additional unidentified genes. An examination of gene expression profiles in 22 high-grade osteosarcoma tumor specimens from 15 patients (including paired primary and metastatic samples from five patients) indicated that von Willebrand factor (vWF) mRNA expression may increase during tumor progression. vWF, a large glycoprotein previously considered to be expressed exclusively by endothelial cells and megakaryocytes, is involved in platelet aggregation and adhesion to the subendothelial matrix, processes critical to hematogenous tumor cell metastasis to the lung. Analysis of paired primary and metastatic osteosarcoma tumor samples from 10 patients revealed an increase in vWF gene expression in metastases (P=0.005). Immunohistochemistry showed that, in addition to the endothelial cells, vWF protein was also detected in osteosarcoma cells in vivo in 13 of 29 tumor specimens as well as in SAOS2, an osteosarcoma cell line. The tumor cell staining correlated positively with high vWF expression in the sample (P=0.006). Although vascular endothelial cells contribute to the vWF mRNA detected in the tumor samples, there was neither any correlation between vascular density (VD) and vWF mRNA expression nor between VD and clinical outcome. These findings suggest that vWF expression is deregulated in osteosarcoma tumors, potentially contributing to metastasis.

  17. Unwinding the von Willebrand factor strings puzzle.

    PubMed

    De Ceunynck, Karen; De Meyer, Simon F; Vanhoorelbeke, Karen

    2013-01-10

    von Willebrand factor (VWF) is amongst others synthesized by endothelial cells and stored as ultra-large (UL) VWF multimers in Weibel-Palade bodies. Although UL-VWF is proteolysed by ADAMTS13 (a disintegrin-like and metalloprotease domain with thrombospondin type-1 motif, number 13) on secretion from endothelial cells, in vitro experiments in the absence of ADAMTS13 have demonstrated that a proportion of these UL-VWF multimers remain anchored to the activated endothelium. These multimers unravel, bind platelets, and wave in the direction of the flow. These so-called VWF "strings" have also been visualized in vivo, lining the lumen of activated mesenteric veins of Adamts13(-/-) mice. Various studies have demonstrated the extraordinary length of these VWF strings, the availability of their platelet binding and ADAMTS13 cleavage sites, and the possible nature of their endothelial attachment. VWF strings are also capable of tethering leukocytes and parasite-infected red blood cells. However, the majority of studies have been performed in the absence of ADAMTS13, a condition only experienced in thrombotic thrombocytopenic purpura. A normal functional role of VWF strings in healthy persons or in other disease pathologies remains unclear. In this review, we discuss some of the puzzling characteristics of VWF strings, and we debate whether the properties of VWF strings in the absence of ADAMTS13 might be relevant for understanding (patho)physiologic mechanisms.

  18. Quantum control by von Neumann measurements

    NASA Astrophysics Data System (ADS)

    Pechen, Alexander; Il'in, Nikolai; Shuang, Feng; Rabitz, Herschel

    2006-11-01

    A general scheme is presented for controlling quantum systems using evolution driven by nonselective von Neumann measurements, with or without an additional tailored electromagnetic field. As an example, a two-level quantum system controlled by nonselective quantum measurements is considered. The control goal is to find optimal system observables such that consecutive nonselective measurement of these observables transforms the system from a given initial state into a state which maximizes the expected value of a target operator (the objective). A complete analytical solution is found including explicit expressions for the optimal measured observables and for the maximal objective value given any target operator, any initial system density matrix, and any number of measurements. As an illustration, upper bounds on measurement-induced population transfer between the ground and the excited states for any number of measurements are found. The anti-Zeno effect is recovered in the limit of an infinite number of measurements. In this limit the system becomes completely controllable. The results establish the degree of control attainable by a finite number of measurements.

  19. Exponential Size Distribution of von Willebrand Factor

    PubMed Central

    Lippok, Svenja; Obser, Tobias; Müller, Jochen P.; Stierle, Valentin K.; Benoit, Martin; Budde, Ulrich; Schneppenheim, Reinhard; Rädler, Joachim O.

    2013-01-01

    Von Willebrand Factor (VWF) is a multimeric protein crucial for hemostasis. Under shear flow, it acts as a mechanosensor responding with a size-dependent globule-stretch transition to increasing shear rates. Here, we quantify for the first time, to our knowledge, the size distribution of recombinant VWF and VWF-eGFP using a multilateral approach that involves quantitative gel analysis, fluorescence correlation spectroscopy, and total internal reflection fluorescence microscopy. We find an exponentially decaying size distribution of multimers for recombinant VWF as well as for VWF derived from blood samples in accordance with the notion of a step-growth polymerization process during VWF biosynthesis. The distribution is solely described by the extent of polymerization, which was found to be reduced in the case of the pathologically relevant mutant VWF-IIC. The VWF-specific protease ADAMTS13 systematically shifts the VWF size distribution toward smaller sizes. This dynamic evolution is monitored using fluorescence correlation spectroscopy and compared to a computer simulation of a random cleavage process relating ADAMTS13 concentration to the degree of VWF breakdown. Quantitative assessment of VWF size distribution in terms of an exponential might prove to be useful both as a valuable biophysical characterization and as a possible disease indicator for clinical applications. PMID:24010664

  20. Richard von Volkmann: surgeon and Renaissance man.

    PubMed

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R; Mubarak, Scott J

    2008-02-01

    Richard von Volkmann (1830-1889), one of the most important surgeons of the 19(th) century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867-1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the "antiseptic technique" to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann's contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children's fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics.

  1. [Determination of von Willebrand factor multimers in Mexican population].

    PubMed

    Hernández-Zamora, Edgar; Zavala-Hernández, Cesar; Viveros-Sandoval, Martha Eva; Ochoa-Rico, Angeles; Martínez-Murillo, Carlos; Reyes-Maldonado, Elba

    2014-01-01

    Antecedentes: la enfermedad de von Willebrand es un padecimiento hereditario en el que la estructura, función y concentración del factor de von Willebrand están alteradas y, en consecuencia, también la interacción plaqueta-factor de von Willebrand-endotelio. En México no hay registros epidemiológicos de la enfermedad, sólo se han efectuado algunos estudios aislados desde el punto de vista clínico y hematológico. Material y métodos: estudio retrospectivo efectuado en 155 mexicanos mestizos, 75 de ellos con diagnóstico presuntivo de enfermedad de von Willebrand, 15 con sospecha de hemofilia A y 65 donadores sanos (testigos). Se realizaron pruebas: básicas de coagulación, especiales y de clasificación: análisis de la composición multimérica. Resultados: 15 pacientes se diagnosticaron con hemofilia A; de los 75 sujetos con sospecha de enfermedad de von Willebrand se diagnosticaron 50 de la manera siguiente: tipo 1 (62%), tipo 2 (22%) [subtipos: 2A (14%), 2B (2%) y 2N (6%)] y tipo 3 (16%). Conclusión: el análisis de los multímeros del factor de von Willebrand es un método que cumple con las características adecuadas para el diagnóstico de la enfermedad de von Willebrand, por lo que es necesario implementar esta metodología para su estudio y mejorar su diagnóstico específico.

  2. Synergistic effects of the SAPK/JNK and the proteasome pathway on glial fibrillary acidic protein (GFAP) accumulation in Alexander disease.

    PubMed

    Tang, Guomei; Xu, Zhiheng; Goldman, James E

    2006-12-15

    Protein aggregates in astrocytes that contain glial fibrillary acidic protein (GFAP), small heat shock proteins, and ubiquitinated proteins are termed Rosenthal fibers and characterize Alexander disease, a leukodystrophy caused by heterozygous mutations in GFAP. The mechanisms responsible for the massive accumulation of GFAP in Alexander disease remain unclear. In this study, we show that overexpression of both wild type and R239C mutant human GFAP led to cytoplasmic inclusions. GFAP accumulation also led to a decrease of proteasome activity and an activation of the MLK2-JNK pathway. In turn, the expression of activated mixed lineage kinases (MLKs) induced JNK activation and increased GFAP accumulation, whereas blocking the JNK pathway decreased GFAP accumulation. Activated MLK also inhibited proteasome function. A direct inhibition of proteasome function pharmacologically further activated JNK. Our data suggest a synergistic interplay between the proteasome and the SAPK/JNK pathway in the context of GFAP accumulation. Feedback interactions among GFAP accumulation, SAPK/JNK activation, and proteasomal hypofunction cooperate to produce further protein accumulation and cellular stress responses.

  3. Correlation of Emkuckfaw Group metagraywackes with the Wedowee Group, Northern Piedmont, Alabama: Implications for the interpretation of the Alexander City fault

    SciTech Connect

    Bieler, D.B. . Geology Dept.)

    1993-03-01

    Recent field studies to clarify stratigraphic relationships between the Elkahatchee Quartz Diorite Gneiss and the Brevard zone lead to the interpretation that part of the Emuckfaw Group is correlative with, and probably structurally continuous with, part of the Wedowee Group. The Josie Leg formation of Bieler and Deininger (1987) is a sequence of metagraywackes and interbedded metapelites; it is here interpreted as a coarse submarine fan facies. The northwestern contact of the unit, frequently mapped as the Alexander City fault, maps into the Wadley Line in the New Site and Daviston quadrangles. The southeastern contact is a sheared contact with structurally overlying migmatitic rocks that include quartzites and calcsilicates. The Josie Leg and Wedowee rocks form a southwesterly plunging synform in which the Elkahatchee lies. Where the contact between the units is gently dipping it is mapped as the Wadley line. Where the contact has been folded and dips steeply, it is highly sheared and is mapped as the Alexander City fault. It is impossible to determine at this time how much the section has been attenuated during the shearing. Although the contact has been interpreted as structural, the data are not unambiguous. The Josie Leg/Wedowee contact may be a stratigraphic contact with the apparent structural discordance reflecting the different mechanical behavior of the contrasting lithologies.

  4. Berechnung von Nichtlinearitätsparametern von RF MOS Mischern mittels Volterra-Reihen

    NASA Astrophysics Data System (ADS)

    Susic, A.; Darrat, A. H.; Mathis, W.

    2011-07-01

    Die Nichtlinearität einer Mischerschaltung bezüglich des Informationssignals führt zu unerwünschten Spektralanteilen am Ausgang des Mischers. Da nicht alle Spektralanteile kritisch sind, müssen bei einer Nichtlinearitätsanalyse nur bestimmte Spektralanteile ermittelt werden. In dieser Arbeit wird ein Verfahren zur Bestimmung der Spektralanteile der Zustandsgrößen im Mischer mit Hilfe der Volterra-Reihe gezeigt. Das Verfahren basiert auf die Methode der nichtlinearen Stromquellen. Es wird sowohl auf nicht-schaltende als auch schaltende Mischer angewendet. Hierbei wird der erste als ein zeitinvariantes System mit zwei Eingängen und der zweite als ein periodisch zeitvariantes System mit einem Eingang modelliert. Das Verfahren wird in dem Computeralgebraprogramm MAPLE für den einfach balancierten MOS Mischer implementiert. Es ermöglicht die Herleitung von semi-symbolischen Ausdrücken für die Spektralanteile in Abhängigkeit von den Entwurfsparametern. Die numerischen Ergebnisse des Verfahrens werden gegenüber Simulationen mit SpectreRF verglichen.

  5. Recombinant von Willebrand factor: a first-of-its-kind product for von Willebrand disease.

    PubMed

    Singal, M; Kouides, P A

    2016-12-01

    von Willebrand disease (VWD) is caused by quantitative or qualitative defects in von Willebrand factor (VWF). The mainstay of therapy is desmopressin, which is, however, not useful in certain forms of VWD notwithstanding adverse events. For these patients, plasma-derived factor VIII (pdFVIII)/VWF concentrates have been available for close to three decades but have a theoretical risk of disease transmission, hypersensitivity/allergic reactions, inhibitors and thrombosis. A recombinant VWF (vonicog alfa, Vonvendi™; manufactured by Baxalta, now part of Shire) was approved by the U.S. Food and Drug Administration (FDA) in December 2015. This review will survey the literature based on a MEDLINE review on the safety, efficacy and pharmacokinetics of Vonvendi. It will also summarize the ongoing studies on Vonvendi available in the public domain. Vonvendi may have an important role in the management of VWD. However, more studies are needed, especially in special populations such as surgical patients, patients with major gastrointestinal bleeding from arteriovenous malformations and pregnant women and children, who are most likely to benefit from it.

  6. Diagnostic Value of Measuring Platelet Von Willebrand Factor in Von Willebrand Disease

    PubMed Central

    Casonato, Alessandra; Cattini, Maria Grazia; Daidone, Viviana; Pontara, Elena; Bertomoro, Antonella; Prandoni, Paolo

    2016-01-01

    Von Willebrand disease (VWD) may be caused by an impaired von Willebrand factor (VWF) synthesis, its increased clearance or abnormal function, or combinations of these factors. It may be difficult to recognize the different contributions of these anomalies. Here we demonstrate that VWD diagnostics gains from measuring platelet VWF, which can reveal a defective VWF synthesis. Measuring platelet VWF revealed that: severe type 1 VWD always coincided with significantly lower platelet and plasma VWF levels, whereas mild forms revealed low plasma VWF levels associated with low or normal platelet VWF levels, and the latter were associated with a slightly shorter VWF survival; type Vicenza (the archetype VWD caused by a reduced VWF survival) featured normal platelet VWF levels despite significantly reduced plasma VWF levels; type 2B patients could have either normal platelet VWF levels associated with abnormal multimer patterns, or reduced platelet VWF levels associated with normal multimer patterns; type 2A patients could have reduced or normal platelet VWF levels, the former associated mainly with type 2A-I, the latter with type 2A-II; plasma and platelet VWF levels were normal in type 2N, except when the defect was associated with a quantitative VWF mutation. Our findings show that measuring platelet VWF helps to characterize VWD, especially the ambiguous phenotypes, shedding light on the mechanisms underlying the disorder. PMID:27532107

  7. Locally Compact Quantum Groups. A von Neumann Algebra Approach

    NASA Astrophysics Data System (ADS)

    Van Daele, Alfons

    2014-08-01

    In this paper, we give an alternative approach to the theory of locally compact quantum groups, as developed by Kustermans and Vaes. We start with a von Neumann algebra and a comultiplication on this von Neumann algebra. We assume that there exist faithful left and right Haar weights. Then we develop the theory within this von Neumann algebra setting. In [Math. Scand. 92 (2003), 68-92] locally compact quantum groups are also studied in the von Neumann algebraic context. This approach is independent of the original C^*-algebraic approach in the sense that the earlier results are not used. However, this paper is not really independent because for many proofs, the reader is referred to the original paper where the C^*-version is developed. In this paper, we give a completely self-contained approach. Moreover, at various points, we do things differently. We have a different treatment of the antipode. It is similar to the original treatment in [Ann. Sci. & #201;cole Norm. Sup. (4) 33 (2000), 837-934]. But together with the fact that we work in the von Neumann algebra framework, it allows us to use an idea from [Rev. Roumaine Math. Pures Appl. 21 (1976), 1411-1449] to obtain the uniqueness of the Haar weights in an early stage. We take advantage of this fact when deriving the other main results in the theory. We also give a slightly different approach to duality. Finally, we collect, in a systematic way, several important formulas. In an appendix, we indicate very briefly how the C^*-approach and the von Neumann algebra approach eventually yield the same objects. The passage from the von Neumann algebra setting to the C^*-algebra setting is more or less standard. For the other direction, we use a new method. It is based on the observation that the Haar weights on the C^*-algebra extend to weights on the double dual with central support and that all these supports are the same. Of course, we get the von Neumann algebra by cutting down the double dual with this unique

  8. Biosynthesis of von Willebrand protein by human megakaryocytes.

    PubMed

    Sporn, L A; Chavin, S I; Marder, V J; Wagner, D D

    1985-09-01

    Immunofluorescence staining of buffy coat smears from a patient with chronic myelogenous leukemia in accelerated phase showed that approximately 13% of all nucleated cells contained von Willebrand protein and, therefore, appeared to be of megakaryocytic origin. This was confirmed by positive staining with antisera against platelet factor 4 and platelet glycoproteins. Short-term cultures of the buffy coat, which lacked endothelial cells, were metabolically labeled with [35S]methionine, and von Willebrand protein was immunopurified from cell lysates and culture medium. Cultures from this patient synthesized and secreted von Willebrand protein, in contrast with cultures from other patients with leukemia, who lacked circulating megakaryocytes, and from normal volunteers. The subunit composition of the megakaryocytic von Willebrand protein was very similar to that of human umbilical vein endothelial cells. The size of the processed subunit (220 kD) and of the cellular (260 kD) and secreted (275 kD) precursors from the two cell types were indistinguishable by gel electrophoresis. Furthermore, the ratio of precursor to processed subunit and the pattern of cellular and secreted nonreduced multimers were very similar. It appears, therefore, that the processing steps in biosynthesis of von Willebrand protein used by the megakaryocytes are very similar to those of umbilical vein endothelial cells.

  9. Biographical sketch: Georg Hermann von Meyer (1815-1892).

    PubMed

    Skedros, John G; Brand, Richard A

    2011-11-01

    This biographical sketch on Georg Hermann von Meyer highlights the interactions in the 1860s that von Meyer, a famous anatomist, had with Karl Culmann, a famous structural engineer and mathematician. The published papers from this interaction caught the attention of Julius Wolff and stimulated his development of the trajectorial hypothesis of bone adaptation--now called "Wolff's Law." The corresponding translations are provided: (1) von Meyer's 1867 paper that highlights the regularity of arched trabecular patterns in various human bones, and his discussions with Culmann about their possible mechanical relevance; and (2) Wolff's 1869 paper that first mentions the correspondence of stress trajectories in a solid, crane-like structure to the arched trabecular patterns in the proximal human femur. This biographical sketch on Georg Hermann von Meyer corresponds to the historic texts, The Classic: The Architecture of the Trabecular bone (by von Meyer), and The Classic: On the Significance of the Architecture of the Spongy Substance for the Question of Bone Growth. A preliminary publication (by Wolff) available at DOIs 10.1007/s11999-011-2041-5 , 10.1007/s11999-011-2042-4 .

  10. Thrombospondin-1 in von Willebrand factor function.

    PubMed

    Bonnefoy, Arnaud; Hoylaerts, Marc F

    2008-10-01

    Thrombospondin-1 (TSP1), expressed in many cells and tissues is abundantly present in platelet alpha-granules, from where it is released upon platelet activation. Murine Tsp1(-/-) platelet studies have revealed that TSP1 is redundant for platelet aggregation, but that it reinforces platelet aggregate stabilization, especially in a shear field. von Willebrand factor (VWF), synthesized by megakaryocytes and endothelial cells is stored both in platelet alpha-granules and in endothelial Weibel-Palade bodies as ultralarge multimers. When released from endothelial cells, these multimers are temporarily retained on the endothelium, to be cleaved by the plasma protease ADAMTS13 into smaller and hemostatically less reactive multimers, released in plasma. This protease shows partial sequence identity with the type 1 (TSR1) and type 2 (TSR2) repeats of TSP1 and contains 1 TSR1 and 6 TSR2 repeats. TSP1, locally released by platelets, competes with ADAMTS13 during VWF proteolysis and controls the degree of VWF multimer processing. In addition, TSP1 and VWF both interact with the platelet GPIb/V/IX membrane complex, primarily in flow. These interactions control the recruitment of platelets to (sub) endothelial VWF and TSP1, exposed to the circulation, as a consequence of vascular inflammation and endothelial injury. TSP1-VWF interactions do not strictly enhance platelet recruitment and secreted TSP1 even weakly competes with the dynamic platelet rolling and adhesion onto VWF. Hence, TSP1 and VWF show partially related hemostatic functions, the most important one being the TSP1 role in the ADAMTS13 operated VWF multimer processing, in pro-inflammatory and thrombogenic conditions.

  11. Periodisches Hitzdrahtverfahren zur Messung von Wärme- und Temperaturleitfähigkeit von geringen Stoffmengen

    NASA Astrophysics Data System (ADS)

    Griesinger, A.; Spindler, K.; Hahne, E.

    Zusammenfassung Es wird ein Meßverfahren zur gleichzeitigen Bestimmung der Wärme- und der Temperaturleitfähigkeit von geringen Stoffmengen beschrieben. Neben Messungen an hochviskosen Flüssigkeiten eignet sich das Verfahren besonders für Messungen an Pulver-Schüttungen. Das Meßverfahren basiert auf dem transienten Hitzdraht-Verfahren. In einem dünnen Platindraht fließt ein sinusförmiger Wechselstrom, der den Draht periodisch erwärmt. Es entstehen thermische Wellen, die in die umgebende Probe eindringen. Die Amplitude und die Phasenlage der thermischen Wellen in der Probe hängen von der Temperaturleitfähigkeit a und der Wärmeleitfähigkeit λ der Probe ab. Die Temperaturschwingung in der Probe wird mit Hilfe des Platindrahtes gemessen, der gleichzeitig als Widerstandsthermometer eingesetzt wird. Meßwerte von Wasser und Glycerin zeigen eine gute Übereinstimmung mit Literaturwerten. Das Meßverfahren zeichnet sich dadurch aus, daß zur Bestimmung der Wärme- und Temperaturleitfähigkeit nur 13 ml einer Probe benötigt werden. Es werden Meßwerte einer Zeolith-Schüttung unter Wasserstoffbeladung dargestellt. A measuring procedure for the simultaneous determination of the thermal conductivity and thermal diffusivity of small quantities is described. The procedure is suited for high-viscous fluids and for powdery material. The measuring principle is based on the transient hot-wire method. A sinusoidal alternating current flows through a thin platinum wire and heats up the wire periodically. This results in thermal waves, which penetrate into the surrounding sample. The amplitude and the phase shift of the thermal waves depend on the thermal diffusivity ``a'' and the thermal conductivity ``λ'' of the sample. The temperature oscillation in the sample is measured by means of the platinum wire, which is simultaneously applied as a resistance thermometer. The values measured for water and glycerine correspond well to those given in literature. Results of the

  12. Committee Opinion No.580: von Willebrand disease in women.

    PubMed

    2013-12-01

    Von Willebrand disease, the most common inherited bleeding disorder among American women, is a common cause of heavy menstrual bleeding and other bleeding problems in women and adolescent girls. Von Willebrand disease and other inherited and acquired disorders of coagulation and hemostasis should be considered in the differential diagnosis of all patients being evaluated for heavy menstrual bleeding, regardless of age. There are many treatment options available for patients with von Willebrand disease and heavy menstrual bleeding, including hormonal and nonhormonal therapies. A multidisciplinary approach to management, which involves obstetrician-gynecologists and hematologists, results in optimal treatment outcomes. Many resources exist for patients and health care providers through the National Heart, Lung, and Blood Institute; National Hemophilia Foundation; and the American Society of Hematology.

  13. The smooth entropy formalism for von Neumann algebras

    NASA Astrophysics Data System (ADS)

    Berta, Mario; Furrer, Fabian; Scholz, Volkher B.

    2016-01-01

    We discuss information-theoretic concepts on infinite-dimensional quantum systems. In particular, we lift the smooth entropy formalism as introduced by Renner and collaborators for finite-dimensional systems to von Neumann algebras. For the smooth conditional min- and max-entropy, we recover similar characterizing properties and information-theoretic operational interpretations as in the finite-dimensional case. We generalize the entropic uncertainty relation with quantum side information of Tomamichel and Renner and discuss applications to quantum cryptography. In particular, we prove the possibility to perform privacy amplification and classical data compression with quantum side information modeled by a von Neumann algebra.

  14. Henry Cavendish, Johann von Soldner, and the deflection of light

    NASA Astrophysics Data System (ADS)

    Will, Clifford M.

    1988-05-01

    The gravitational deflection of light based on Newtonian theory and the corpuscular model of light was calculated, but never published, around 1784 by Henry Cavendish, almost 20 years earlier than the first published calculation by Johann Georg von Soldner. The two results are slightly different because, while Cavendish treated a light ray emitted from infinity, von Soldner treated a light ray emitted from the surface of the gravitating body. At the first order of approximation, they agree with each other; both are one-half the value predicted by general relativity and confirmed by experiment.

  15. Endothelial dysfunction in von Willebrand disease: angiogenesis and angiodysplasia.

    PubMed

    Randi, Anna M

    2016-05-01

    In recent years, new functions for the haemostatic protein von Willebrand Factor (VWF) have emerged. Amongst these is the ability to modulate the development of new blood vessels, a process called angiogenesis. The subtle effects that VWF exerts on blood vessel formation and stability may be relevant for the small but significant fraction of patients with von Willebrand disease (VWD) who also present with vascular malformations (angiodysplasia) in the gastrointestinal tract, often responsible for intractable bleeding. This review will briefly summarise the evidence and discuss the molecular pathways involved.

  16. An Accurate von Neumann's Law for Three-Dimensional Foams

    SciTech Connect

    Hilgenfeldt, Sascha; Kraynik, Andrew M.; Koehler, Stephan A.; Stone, Howard A.

    2001-03-19

    The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with detailed simulations and experiments. The average growth rate of a bubble with F faces is shown to be proportional to F{sup 1/2} for large F , in contrast to the conjectured linear dependence. Accounting for foam disorder in the model further improves the agreement with data.

  17. The smooth entropy formalism for von Neumann algebras

    SciTech Connect

    Berta, Mario; Furrer, Fabian; Scholz, Volkher B.

    2016-01-15

    We discuss information-theoretic concepts on infinite-dimensional quantum systems. In particular, we lift the smooth entropy formalism as introduced by Renner and collaborators for finite-dimensional systems to von Neumann algebras. For the smooth conditional min- and max-entropy, we recover similar characterizing properties and information-theoretic operational interpretations as in the finite-dimensional case. We generalize the entropic uncertainty relation with quantum side information of Tomamichel and Renner and discuss applications to quantum cryptography. In particular, we prove the possibility to perform privacy amplification and classical data compression with quantum side information modeled by a von Neumann algebra.

  18. Weibel-Palade bodies: a window to von Willebrand disease.

    PubMed

    Valentijn, K M; Eikenboom, J

    2013-04-01

    Weibel-Palade bodies (WPBs) are the storage organelles for von Willebrand factor (VWF) in endothelial cells. VWF forms multimers that assemble into tubular structures in WPBs. Upon demand, VWF is secreted into the blood circulation, where it unfolds into strings that capture platelets during the onset of primary hemostasis. Numerous mutations affecting VWF lead to the bleeding disorder von Willebrand disease. This review reports the recent findings on the effects of VWF mutations on the biosynthetic pathway of VWF and its storage in WPBs. These new findings have deepened our understanding of VWF synthesis, storage, secretion, and function.

  19. Ernst von Glasersfeld's Radical Constructivism and Truth as Disclosure

    ERIC Educational Resources Information Center

    Joldersma, Clarence W.

    2011-01-01

    In this essay Clarence Joldersma explores radical constructivism through the work of its most well-known advocate, Ernst von Glasersfeld, who combines a sophisticated philosophical discussion of knowledge and truth with educational practices. Joldersma uses Joseph Rouse's work in philosophy of science to criticize the antirealism inherent in…

  20. Dr. von Braun Conferring With NASA Headquarters Officials

    NASA Technical Reports Server (NTRS)

    1961-01-01

    This photograph, dated November 13, 1961, shows Dr. von Braun conferring with two officials from NASA Headquarters. Dr. Brainered Holmes is on the left. Dr. Nicholas Golovin is in the center. Holmes was Director of NASA's Office of Marned Space Flight. Golovin was Director of Systems Engineering at Headquarters.

  1. Von Kármán between Aachen and Pasadena

    NASA Astrophysics Data System (ADS)

    Krause, Egon; Kalkmann, Ulrich

    2013-05-01

    In the Introduction the reader is referred back to the academic ceremonials held after Theodore von Kármán's death in Aachen in May 1963. His work as the first director of the Aerodynamisches Institut (Institute of Aerodynamics) of the RWTH Aachen University of Technology from 1913 on and his initiative to re-establish international cooperation after World War I, resulting in the International Union of Theoretical and Applied Mechanics (IUTAM), are commented on. The following chapter describes von Kármán's relation to his former teacher Ludwig Prandtl. Some of von Kármán's scientific contributions during his time in Aachen are briefly reviewed. Thereafter, his first contacts to the California Institute of Technology are covered. Finally, the scientific and political circumstances, which led to von Kármán's decision to leave Germany in the early thirties, are elucidated in some detail. The English translation of the titles of the Aachen papers is given in Appendix I.

  2. Dr. Wernher Von Braun near the mobile launcher.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. George Mueller, NASA associate administrator for manned space flight, and Dr. Wernher Von Braun (right), director of the Marshall Space Flight Center, are seen near the mobile launcher carrying a 363 foot tall Saturn V space launch vehicle as the rocket is rolled from the vehicle assembly building at KSC for its three mile trip to the launch pad.

  3. Wernher von Braun: Reflections on His Contributions to Space Exploration

    NASA Technical Reports Server (NTRS)

    Goldman, Arthur E.

    2012-01-01

    In 1950, Dr. Wernher von Braun and approximately 100 of his team members came to Huntsville, Alabama, to begin work with the Army on what would later become America's historic space program. He would later serve as the first director of the Marshall Space Flight Center and led the development of the Saturn V launch vehicle that launched seven crewed American mission to the moon, as well as America s first space station, Skylab. Von Braun is best known for his team s technical achievements. He realized his dream of exploring outer space by helping place humans on the moon. His engineering and managerial talent during the Apollo era had contributed to a technological revolution. He was by all accounts a good engineer, but he was only one among many. What set Von Braun apart were his charisma, his vision, and his leadership skills. He inspired loyalty and dedication in the people around him. He understood the importance of communicating his vision to his team, to political and business leaders and the public. Today, the Marshall Center continues his vision by pursuing engineering and scientific projects that will continue to open space to exploration. This presentation will discuss Von Braun's impact on Huntsville, the Marshall Center, the nation and the world and look at his contributions in context of where world space exploration is today.

  4. Current therapy in children and adolescents with von Willebrand disease.

    PubMed

    Buga-Corbu, I; Arion, C

    2014-06-15

    The article represents a review of recent data about the therapy of von Willebrand disease in children and adolescents (hereditary as well as acquired forms of the disease). The treatment of bleeding events in these patients, the indications in different subtypes, and the future lines of research are mentioned.

  5. von Braun Examines Bendix Mobility Test Article (MTA)

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Marshall Space Flight Center (MSFC) director, Wernher von Braun, and others examine one concept of a possible Lunar Roving Vehicle (LRV) built by the Bendix Corporation. The data provided by the MTA helped in designing the LRV, developed under the direction of MSFC. The LRV was designed to allow Apollo astronauts a greater range of mobility during lunar exploration missions.

  6. von Braun Examines Bendix Mobility Test Article (MTA)

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Marshall Space Flight Center (MSFC) director, Wernher von Braun, and a visitor, examine one concept of a possible Lunar Roving Vehicle (LRV) built by the Bendix Corporation. The data provided by the MTA helped in designing the LRV, developed under the direction of MSFC. The LRV was designed to allow Apollo astronauts a greater range of mobility during lunar exploration missions.

  7. Dr. von Braun With a Model of a Launch Vehicle

    NASA Technical Reports Server (NTRS)

    1950-01-01

    Dr. von Braun stands beside a model of the upper stage (Earth-returnable stage) of the three-stage launch vehicle built for the series of the motion picture productions of space flight produced by Walt Disney in the mid-1950's.

  8. Treasure in the Library Attic: Von Ranke at Syracuse.

    ERIC Educational Resources Information Center

    Coville, Bruce

    1984-01-01

    Traces history of private library of German scholar, Leopold von Ranke, which was purchased by Syracuse University in 1888. Efforts of librarian Charles W. Bennett in 1870s and Professor James Powell beginning in late 1960s, and restoration and cataloging of collection are highlighted. Items from the collection are noted. (EJS)

  9. The Influence of Field Marshal Colmar Von Der Goltz on Ottoman Military Effectiveness in Mesopotamia: December 1915 to April 1916

    DTIC Science & Technology

    2012-02-23

    the Ottoman Fifth Army was activated to defend the Dardanelles, and the Ottomans gave Limon von Sanders command. With Limon von Sanders’ move to...Fifth Army, von der Goltz took command of the First Army and the German military mission which were both previously commanded by Limon von Sanders.51

  10. Hemostatic efficacy, safety, and pharmacokinetics of a recombinant von Willebrand factor in severe von Willebrand disease

    PubMed Central

    Gill, Joan C.; Castaman, Giancarlo; Windyga, Jerzy; Kouides, Peter; Ragni, Margaret; Leebeek, Frank W. G.; Obermann-Slupetzky, Ortrun; Chapman, Miranda; Fritsch, Sandor; Pavlova, Borislava G.; Presch, Isabella

    2015-01-01

    This phase 3 trial evaluated the safety and hemostatic efficacy of a recombinant von Willebrand factor (rVWF) for treatment of bleeds in severe von Willebrand disease (VWD). rVWF was initially administered together with recombinant factor VIII (rFVIII) and subsequently alone, as long as hemostatic factor VIII activity (FVIII:C) levels were maintained. Pharmacokinetics (PK) were evaluated in a randomized cross-over design (rVWF vs rVWF:rFVIII at 50 IU VWF:ristocetin cofactor activity [RCo]/kg). Bleed control for all treated bleeds (N = 192 bleeds in 22 subjects) was rated good or excellent (96.9% excellent; 119 of 122 minor, 59 of 61 moderate, and 6 of 7 major bleeds) on a 4-point scale (4 = none to 1 = excellent). A single infusion was effective in 81.8% of bleeds. Treatment success, defined as the number of subjects with a mean efficacy rating of <2.5, was 100%. The PK profile of rVWF was not influenced by rFVIII (mean VWF:RCo terminal half-life: 21.9 hours for rVWF and 19.6 hours for rVWF:rFVIII). FVIII:C levels increased rapidly after rVWF alone, with hemostatic levels achieved within 6 hours and sustained through 72 hours after infusion. Eight adverse events (AEs; 6 nonserious AEs in 4 subjects and 2 serious AEs [chest discomfort and increased heart rate, without cardiac symptomatology] concurrently in 1 subject) were associated with rVWF. There were no thrombotic events or severe allergic reactions. No VWF or FVIII inhibitors, anti-VWF binding antibodies, or antibodies against host cell proteins were detected. These results show that rVWF was safe and effective in treating bleeds in VWD patients and stabilizes endogenous FVIII:C, which may eliminate the need for rFVIII after the first infusion. This trial was registered at www.clinicaltrials.gov as #NCT01410227. PMID:26239086

  11. Hemostatic efficacy, safety, and pharmacokinetics of a recombinant von Willebrand factor in severe von Willebrand disease.

    PubMed

    Gill, Joan C; Castaman, Giancarlo; Windyga, Jerzy; Kouides, Peter; Ragni, Margaret; Leebeek, Frank W G; Obermann-Slupetzky, Ortrun; Chapman, Miranda; Fritsch, Sandor; Pavlova, Borislava G; Presch, Isabella; Ewenstein, Bruce

    2015-10-22

    This phase 3 trial evaluated the safety and hemostatic efficacy of a recombinant von Willebrand factor (rVWF) for treatment of bleeds in severe von Willebrand disease (VWD). rVWF was initially administered together with recombinant factor VIII (rFVIII) and subsequently alone, as long as hemostatic factor VIII activity (FVIII : C) levels were maintained. Pharmacokinetics (PK) were evaluated in a randomized cross-over design (rVWF vs rVWF:rFVIII at 50 IU VWF:ristocetin cofactor activity [RCo]/kg). Bleed control for all treated bleeds (N = 192 bleeds in 22 subjects) was rated good or excellent (96.9% excellent; 119 of 122 minor, 59 of 61 moderate, and 6 of 7 major bleeds) on a 4-point scale (4 = none to 1 = excellent). A single infusion was effective in 81.8% of bleeds. Treatment success, defined as the number of subjects with a mean efficacy rating of <2.5, was 100%. The PK profile of rVWF was not influenced by rFVIII (mean VWF:RCo terminal half-life: 21.9 hours for rVWF and 19.6 hours for rVWF:rFVIII). FVIII : C levels increased rapidly after rVWF alone, with hemostatic levels achieved within 6 hours and sustained through 72 hours after infusion. Eight adverse events (AEs; 6 nonserious AEs in 4 subjects and 2 serious AEs [chest discomfort and increased heart rate, without cardiac symptomatology] concurrently in 1 subject) were associated with rVWF. There were no thrombotic events or severe allergic reactions. No VWF or FVIII inhibitors, anti-VWF binding antibodies, or antibodies against host cell proteins were detected. These results show that rVWF was safe and effective in treating bleeds in VWD patients and stabilizes endogenous FVIII : C, which may eliminate the need for rFVIII after the first infusion. This trial was registered at www.clinicaltrials.gov as #NCT01410227.

  12. Expression of abnormal von Willebrand factor by endothelial cells from a patient with type IIA von Willebrand disease.

    PubMed Central

    Levene, R B; Booyse, F M; Chediak, J; Zimmerman, T S; Livingston, D M; Lynch, D C

    1987-01-01

    Studies were conducted to characterize the biosynthesis of von Willebrand factor (vWf) by cultured endothelial cells (EC) derived from the umbilical vein of a patient with type IIA von Willebrand disease. The patient's EC, compared with those from normal individuals, produced vWf that had decreased amounts of large multimers and an increase in rapidly migrating satellite species, features characteristic of plasma vWf from patients with type IIA von Willebrand disease. The type IIA EC did produce a full spectrum of vWf multimers in both cell lysates and postculture medium, although the relative amounts of the largest species were decreased. The large multimers were degraded in conjunction with the appearance of rapidly migrating satellites that contained approximately equal to 170-kDa proteolytic fragments, suggesting that this patient's functional defect is due to abnormal proteolysis and not to a primary failure of vWf subunit oligomerization. Moreover, the observed degradation appears to result from an abnormal vWf molecule and not elevated protease levels. These results suggest that this patient's von Willebrand disease phenotype is caused by increased proteolytic sensitivity of his vWf protein. Images PMID:3306682

  13. Principles of care for the diagnosis and treatment of von Willebrand disease.

    PubMed

    Castaman, Giancarlo; Goodeve, Anne; Eikenboom, Jeroen

    2013-05-01

    Von Willebrand disease is a common autosomal inherited bleeding disorder caused by quantitative or qualitative defects of von Willebrand factor, a multi-adhesive protein that binds platelets to exposed subendothelium and carries factor VIII in circulation. As a result of von Willebrand factor deficiency or abnormality, levels of factor VIII, the protein deficient in hemophilia A, may be variably reduced. Clinical manifestations are mainly represented by mucous membrane and of soft tissue bleeding. Their severity is variable depending on the degree of von Willebrand factor and factor VIII reduction. While a clear-cut diagnosis is easy in severe von Willebrand factor reductions, the advantage of pursuing a definite diagnosis in mild or dubious cases should be weighed against the risk of over-medicalization. The aim of treatment is to correct the dual defect of hemostasis caused by the abnormal/reduced von Willebrand factor and the concomitant deficiency of factor VIII. Desmopressin is the treatment of choice for type 1 von Willebrand disease patients with factor VIII and von Willebrand factor levels of 10 U/dL or over who have proved responsive to a test-infusion with the compound. Von Willebrand factor/factor VIII concentrates are needed when desmopressin is ineffective (mainly type 2 and 3 von Willebrand disease).

  14. Altered megakaryocytopoiesis in von Willebrand type 2B disease.

    PubMed

    Nurden, A T; Federici, A B; Nurden, P

    2009-07-01

    Type 2B von Willebrand disease (VWD2B) is caused by gain-of-function amino acid substitutions in the von Willebrand factor (VWF) A1 domain. These allow facilitated binding of mutated VWF to platelet GPIbalpha with prolonged lifetimes of VWF bonds and enhanced ADAMTS-13 cleavage of large VWF multimers. A bleeding rather than prothrombotic syndrome is due to: (i) decreased large VWF multimers in plasma; (ii) limited thrombus formation; and (iii) thrombocytopenia affecting some but not all patients. Accumulating evidence points to an altered megakaryocytopoiesis in VWD2B with the production of enlarged or giant platelets showing an abnormal ultrastructure and, in a cohort of patients, the presence of circulating platelet agglutinates. In fact, evidence from in vitro cultures and marrow aspirates suggests that the upregulated VWF function can lead to abnormal VWF trafficking in megakaryocytes, a modified platelet production with interacting proplatelets, and the presence or even release of platelet agglutinates in the bone marrow.

  15. Water Experiments Related To The "Von Karman Sodium" Dynamo Project

    NASA Astrophysics Data System (ADS)

    Marie, L.; Bourgoin, M.; Petrelis, F.; Roy, J.; Burguete, J.; Chiffaudel, A.; Daviaud, F.; Fauve, S.; Odier, P.; Pinton, J.-F.

    2002-07-01

    The purpose of the "Von Karman Sodium" (V.K.S.) experiment is to study the "Dynamo Effect," namely the spontaneous generation of magnetic field in a flow of electrically conducting fluid. The device has been built at CEA / Cadarache, in collaboration with CEA / Saclay, Ecole Normale Superieure de Lyon and Ecole Normale Superieure de Paris. It consists of a cylindrical vessel, filled with liquid Sodium, in which two coaxial rotating disks induce a Von-Karman type flow. Several experimental runs have taken place since June 2000. In order to optimize the V.K.S. set-up, a half-scale water prototype has also been built. It has allowed us to measure mean velocity profiles, as well as pressure fluctuations and mechanical power dissipation. We have observed that under certain circumstances the mean component of the turbulent flow can undergo a global bifurcation.

  16. The molecular characterization of von Willebrand disease: good in parts.

    PubMed

    James, P D; Lillicrap, D

    2013-04-01

    Since the cloning of the gene that encodes von Willebrand factor (VWF), 27 years ago, significant progress has been made in our understanding of the molecular basis of the most common inherited bleeding disorder, von Willebrand disease (VWD). The molecular pathology of this condition represents a range of genetic mechanisms, some of which are now very well characterized, and others that are still under investigation. In general, our knowledge of the molecular basis of type 2 and 3 VWD is now well advanced, and in some instances this information is being used to enhance clinical management. In contrast, our understanding of the molecular pathogenesis of the most common form of VWD, type 1 disease, is still at an early stage, with preliminary evidence that this phenotype involves a complex interplay between environmental factors and the influence of genetic variability both within and outside of the VWF locus.

  17. An update on type 2B von Willebrand disease.

    PubMed

    Mikhail, Sameh; Aldin, Ehab Saad; Streiff, Michael; Zeidan, Amer

    2014-04-01

    Type 2B von Willebrand disease (VWD) accounts for fewer than 5% of all VWD patients. In this disease, mutations in the A1 domain result in increased von Willebrand factor (VWF) binding to platelet GPIbα receptors, causing increased platelet clearance and preferential loss of high molecular weight VWF multimers. Diagnosis is complicated because of significant clinical variations even among patients with identical mutations. Platelet transfusion often provides suboptimal results since transfused platelets may be aggregated by the patients' abnormal VWF. Desmopressin may cause a transient decrease in platelet count that could lead to an increased risk of bleeding. Replacement therapy with factor VIII/VWF concentrates is the most effective approach to prevention and treatment of bleeding in type 2B VWD.

  18. Marshall-Stickler phenotype associated with von Willebrand disease

    SciTech Connect

    MacDonald, M.R.; Baker, K.S.; Schaefer, G.B.

    1997-01-20

    We report on 6 individuals from three different kindreds with Marshall-Stickler (MS) phenotype, with characteristic orofacial abnormalities, arthropathy, deafness, and eye findings, all of whom were discovered to have a mild bleeding diathesis and coagulation-study findings consistent with mild von Willebrand disease (vWD). MS syndrome has been linked in some cases to the type II procollagen gene (COL2A1) on chromosome 12q, and to the collagen XI gene (COL11A2) on chromosome 6. The von Willebrand factor (vWF) is encoded by a 180-Kb gene located on the short arm of chromosome 12. This is the first reported association of these two disorders. 26 refs., 5 figs., 1 tab.

  19. Interpolatability distinguishes LOCC from separable von Neumann measurements

    SciTech Connect

    Childs, Andrew M.; Leung, Debbie; Mančinska, Laura; Ozols, Maris

    2013-11-15

    Local operations with classical communication (LOCC) and separable operations are two classes of quantum operations that play key roles in the study of quantum entanglement. Separable operations are strictly more powerful than LOCC, but no simple explanation of this phenomenon is known. We show that, in the case of von Neumann measurements, the ability to interpolate measurements is an operational principle that sets apart LOCC and separable operations.

  20. [Clemens Freiherr von Pirquet, developer of the concept of allergy].

    PubMed

    Bergmann, K C

    2006-07-20

    The pediatrician and scientist, Clemens Freiherr von Pirquet (1874-1929) was the first to coin the term "allergy". His experiments with Behring's serum, which he administered to sick children, led him to an awareness of an interaction between the human organism and pathogens. In his article published in the Müncher Medizinischen Wochenschrift in 1906, he laid the foundation stone for modern allergology.

  1. Baron von Zach's business relations with the Munich entrepreneur Joseph von Utzschneider (German Title: Geschäftsbeziehungen des Barons von Zach zu dem Münchner Unternehmer Joseph von Utzschneider)

    NASA Astrophysics Data System (ADS)

    Schneider, Ivo

    The relationship between the astronomer von Zach on the one side and the entrepreneur Joseph von Utzschneider and his partner Georg von Reichenbach on the other dates presumably from the year 1807 when Zach spent two months in Munich. Already in the same year Zach had ordered an instrument for himself and began to solicit business for the institute of Reichenbach, Utzschneider, and Liebherr, which was founded in 1804. One of the clients canvassed by Zach was the director of the observatory in Naples Zuccari. Zuccari had ordered the whole equipment for the new observatory from this institute in 1813. The instruments for Naples, which were completed in 1814, were sent accompanied by Reichenbach by land and sea to their destination where Reichenbach supervised their setup. At that time Reichenbach had separated from Utzschneider who kept the optical institute in Benediktbeuern with his new partner Joseph von Fraunhofer whereas Reichenbach became owner of the mathematical-mechanical institute in Munich. For personal and economical reasons Utzschneider began soon after to produce not only optical glass but also optical devices similar to those offered by Reichenbach. As soon as two institutes in Munich competed against each other on the market for sophisticated geodetical and astronomical instruments Zach sided with Utzschneider. Zach's main professional argument for this decision was that both competitors got the optical glass for their instruments from Utzschneider's optical institute in Benediktbeuern. This meant that Utzschneider had first choice and so the optical part of his instruments could be considered as better than that of Reichenbach`s instruments. Zach's role as an agent in Italy and France for the sale of products coming from Utzschneider's manufactories is highlighted by three of Zach's letters to Utzschneider from 1817 and 1818, two of which are reproduced here for the first time.

  2. Johann Baptist von Schweitzer: the queer Marx loved to hate.

    PubMed

    Kennedy, H

    1995-01-01

    Despite his conviction on a morals charge involving a boy, the early German Social Democrat Johann Baptist von Schweitzer went on to have a successful political career. His life furnishes the context to present remarks by his political opponents Marx and Engels, which reveal their deep-seated homophobia. It is pointed out that this has been glossed over by the translations of the recently published Marx/Engels Collected Works. Some remarks on boy-love and anarchism are appended.

  3. Dr. von Braun In Front of a Display of Missiles

    NASA Technical Reports Server (NTRS)

    1960-01-01

    In this photo, Director of the US Army Ballistic Missile Agency (ABMA) Development Operations Division, Dr. Wernher von Braun, is standing before a display of Army missiles celebrating ABMA's Fourth Open House. The missiles in the background include (left to right) a satellite on a Juno II shroud with a Nike Ajax pointing left in front of a Jupiter missile. The Lacrosse is in front of the Juno II. The Nike Hercules points skyward in front of the Juno II and the Redstone.

  4. Screening of Von Willebrand Disease in Iranian Women With Menorrhagia

    PubMed Central

    Rahbar, Nahid; Faranoush, Mohammad; Ghorbani, Raheb; Sadr Alsadat, Bahare

    2015-01-01

    Background: Menorrhagia is a common health problem in women, particularly those with bleeding disorders. Little is known about the course of menorrhagia or other bleeding symptoms in women with the most common congenital bleeding disorder, von Willebrand disease (vWD). Objectives: The aim of this study was to estimate the prevalence of vWD in women with diagnosed menorrhagia. Materials and Methods: In this cross-sectional study, a total of 460 consecutive patients, presenting menorrhagia, were analyzed. The initial screening and confirmation tests for the diagnosis of vWD included determination of prothrombin time (PT), partial thromboplastin time (PTT), bleeding time (BT), fibrinogen, factor VIII, vWF antigen, and vWF activity. A questionnaire was filled for every patient. The data were then analyzed using the SPSS software. Results: Mean age of our patients was 32.5 ± 10.6 years. The level of von Willebrand factor in 22.5% and von Willebrand activity in 19.6% of patients was abnormal. The prevalence of vWD among patients with menorrhagia was 24%. Conclusions: The high prevalence of vWD among our patients was the same as other previous reports, suggesting low awareness about this disease and under diagnosis of mild cases. PMID:25763275

  5. The British Interplanetary Society - Val Cleaver and Wernher von Braun

    NASA Astrophysics Data System (ADS)

    Willhite, I. P.

    This article is concerned with the early relationship between Wernher von Braun and the British Interplanetary Society (BIS). The BIS/Wernher von Braun/Val Cleaver correspondence files located here at the US Space & Rocket Center in Huntsville, Alabama are unparalleled. As one reads the stimulating comments between Cleaver and von Braun, the need to share their thoughts prevails. Following is an excerpt from one letter that whets ones appetite for more. 10 June 1951 Cleaver writes, “I'm so glad you enjoyed my last letter, and look forward to your promised further contribution to our discussion of the ethics of science in general and astronautics in particu- lar. As regards the one particular point on which you found yourself unable to hold your fire, I should say there are really two distinct issues at stake:. . .” This article attempts to represent the best of the letters as they goad each other on scientific principles, means to prevent wars, and other philosophic ideas.

  6. Structure of von Willebrand factor and its function in platelet adhesion and thrombus formation.

    PubMed

    Ruggeri, Z M

    2001-06-01

    The adhesive protein von Willebrand factor mediates the initiation and progression of thrombus formation at sites of vascular injury. von Willebrand factor is synthesized in endothelial cells and megakaryocytes as a very large polymer composed of identical subunits. In the plasma, it appears as a series of multimers of regularly decreasing molecular mass, from several thousand to 500 kDa. The size of circulating von Willebrand factor multimers is controlled by proteolytic cleavage carried out by a specific protease. The biological functions of von Willebrand factor are exerted through specific domains that interact with extracellular matrix components and cell membrane receptors to promote the initial tethering and adhesion of platelets to subendothelial surfaces, as well as platelet aggregation. Moreover, von Willebrand factor binds the procoagulant co-enzyme, factor VIII, contributing to its stability and, indirectly, to its function in the generation of fibrin. This chapter presents a review of current knowledge on the structure, biosynthesis and functions of von Willebrand factor.

  7. Operational Leadership: A Case of General Helmuth von Moltke (The Younger)

    DTIC Science & Technology

    2007-11-02

    makes his decision too late to have an impact. II. Historical Framework Helmuth Johannes Ludwig von Moltke, known as von Moltke (The Younger) to distin...T. N. Dupuy, A Genius for War (Englewood Cliffs, NJ: Prentis-Hall, Inc. 1977) 140. 1 Otto Friedrich , Blood and Iron: From Bismarck to Hitler the von...Press, 1996) 160. 1 Tuchman, The Guns of August, 73. 1 Friedrich , Blood and Iron, 229. 1 Holmes, “The Schlieffen Plan,” 13. ii

  8. Post-traumatic stress reactions before the advent of post-traumatic stress disorder: potential effects on the lives and legacies of Alexander the Great, Captain James Cook, Emily Dickinson, and Florence Nightingale.

    PubMed

    Mackowiak, Philip A; Batten, Sonja V

    2008-12-01

    Evidence is presented that Alexander the Great, Captain James Cook, Emily Dickinson, and Florence Nightingale each developed symptoms consistent with post-traumatic stress disorder in the aftermath of repeated potentially traumatizing events of differing character. Their case histories also varied with respect to background, premorbid personality style, risk factors, clinical presentation, and course of the illness, illustrating the pleomorphic character of the disorder, as well as the special problems in diagnosing it in historical figures.

  9. Clumping factor A, von Willebrand factor-binding protein and von Willebrand factor anchor Staphylococcus aureus to the vessel wall.

    PubMed

    Claes, J; Liesenborghs, L; Peetermans, M; Veloso, T R; Missiakas, D; Schneewind, O; Mancini, S; Entenza, J M; Hoylaerts, M F; Heying, R; Verhamme, P; Vanassche, T

    2017-02-09

    Essentials Staphylococcus aureus (S. aureus) binds to endothelium via von Willebrand factor (VWF). Secreted VWF-binding protein (vWbp) mediates S. aureus adhesion to VWF under shear stress. vWbp interacts with VWF and the Sortase A-dependent surface protein Clumping factor A (ClfA). VWF-vWbp-ClfA anchor S. aureus to vascular endothelium under shear stress.

  10. The question of sign-language and the utility of signs in the instruction of the deaf: two papers by Alexander Graham Bell (1898).

    PubMed

    Bell, Alexander Graham

    2005-01-01

    Alexander Graham Bell is often portrayed as either hero or villain of deaf individuals and the Deaf community. His writings, however, indicate that he was neither, and was not as clearly definite in his beliefs about language as is often supposed. The following two articles, reprinted from The Educator (1898), Vol. V, pp. 3-4 and pp. 38-44, capture Bell's thinking about sign language and its use in the classroom. Contrary to frequent claims, Bell does not demand "oral" training for all deaf children--even if he thinks it is the superior alternative--but does advocate for it for "the semi-deaf" and "the semi-mute." "In regard to the others," he writes, "I am not so sure." Although he clearly voices his support for oral methods and fingerspelling (the Rochester method) over sign language, Bell acknowledges the use and utility of signing in a carefully-crafted discussion that includes both linguistics and educational philosophy. In separating the language used at home from that in school and on the playground, Bell reveals a far more complex view of language learning by deaf children than he is often granted. (M. Marschark).

  11. An autopsied case of adult-onset bulbospinalform Alexander disease with a novel S393R mutation in the GFAP gene.

    PubMed

    Iwasaki, Yasushi; Saito, Yufuko; Mori, Keiko; Ito, Masumi; Mimuro, Maya; Aiba, Ikuko; Saito, Kozo; Mizuta, Ikuko; Yoshida, Tomokatsu; Nakagawa, Masanori; Yoshida, Mari

    2015-01-01

    A 50-year-old Japanese man with no apparent family history noticed diplopia. He gradually showed gait disturbance and dysuria. Abducens disorder of eye movement with nystagmus, tongue atrophy with fasciculation, spastic tetraparesis, and sensory disturbance were also observed. MRI showed severe atrophy of the medulla oblongata to the cervical cord ("tadpole appearance"). Tracheotomy and gastrostomy were performed 7 years after onset due to the development of bulbar palsy. Death occurred following respiratory failure after 11 years total disease duration. The brain weighed 1,380 g. The cerebrum, cerebellum, midbrain, and upper pons were preserved from atrophy, but the medulla oblongata to the cervical cord showed severe atrophy. A few Rosenthal fibers were observed in the cerebral white matter, basal ganglia, and cerebellum, whereas numerous Rosenthal fibers were observed in the medulla oblongata to the cervical cord. Myelin loss with relatively preserved axons was extensively observed from the middle of the pons to the spinal cord. The clinicopathological diagnosis was adult-onset bulbospinal-form Alexander disease. Glial fibrillary acidic protein (GFAP) gene analysis revealed a novel mutation of S393R. Expression patterns of S393R mutant GFAP using adrenal carcinoma-derived cells (SW13 cells) showed a decreased number of filamentous structures and abnormal aggregates.

  12. Spin torque oscillator neuroanalog of von Neumann's microwave computer.

    PubMed

    Hoppensteadt, Frank

    2015-10-01

    Frequency and phase of neural activity play important roles in the behaving brain. The emerging understanding of these roles has been informed by the design of analog devices that have been important to neuroscience, among them the neuroanalog computer developed by O. Schmitt and A. Hodgkin in the 1930s. Later J. von Neumann, in a search for high performance computing using microwaves, invented a logic machine based on crystal diodes that can perform logic functions including binary arithmetic. Described here is an embodiment of his machine using nano-magnetics. Electrical currents through point contacts on a ferromagnetic thin film can create oscillations in the magnetization of the film. Under natural conditions these properties of a ferromagnetic thin film may be described by a nonlinear Schrödinger equation for the film's magnetization. Radiating solutions of this system are referred to as spin waves, and communication within the film may be by spin waves or by directed graphs of electrical connections. It is shown here how to formulate a STO logic machine, and by computer simulation how this machine can perform several computations simultaneously using multiplexing of inputs, that this system can evaluate iterated logic functions, and that spin waves may communicate frequency, phase and binary information. Neural tissue and the Schmitt-Hodgkin, von Neumann and STO devices share a common bifurcation structure, although these systems operate on vastly different space and time scales; namely, all may exhibit Andronov-Hopf bifurcations. This suggests that neural circuits may be capable of the computational functionality as described by von Neumann.

  13. Otto von Guericke and 17th century cosmology

    NASA Astrophysics Data System (ADS)

    Knobloch, Eberhard

    Otto von Guericke's scientific method was based on reason and experimental science. His cosmology was embedded in theology and can be interpreted as a refutation of Descartes' worldview. He used Nicolaus Cusanus' theory of quantities in order to characterize space. The notion of space has to be distinguished from that of world or heaven. Forces play a crucial role in this respect described by Athanasius Kircher in his "Celestial Journey". Guericke read this work very diligently. In spite of some obvious similarities between Guericke's and Newton's scientific aims and methods there are crucial differences between the scientific convictions and results of these scholars.

  14. Nutzergerechte Entwicklung der Mensch-Maschine-Interaktion von Fahrerassistenzsystemen

    NASA Astrophysics Data System (ADS)

    König, Winfried

    Durch langjährige Forschungen bei Kfz-Herstellern, Zulieferfirmen und an Hochschulen sind umfangreiche, aber dennoch lückenhafte Erkenntnisse über das Zusammenspiel zwischen FAS und Nutzer gewonnen worden. In deutschen und internationalen Projekten wie z. B. PROMETHEUS, DRIVE, MOTIV, INVENT, RESPONSE und AKTIV haben sich Kfz-Hersteller, Zulieferfirmen, Hochschulen und weitere staatliche und private Forschungseinrichtungen zusammengefunden, um die vorwettbewerbliche Forschung für derartige Systeme voranzutreiben. Im folgenden Kapitel sollen einige der gewonnenen Kenntnisse dargelegt werden, um die Entwicklung des HMI von FAS zu erleichtern.

  15. Kernschmelze Der nachhaltige Einfluss von Nuklearwaffen auf Politik und Wirtschaft

    NASA Astrophysics Data System (ADS)

    Greiner, Bernd

    "Was sollen wir von einer Kultur halten, der die Ethik stets als wesentliches Element des menschlichen Lebens galt, die aber - außer in fachlicher oder spieltheoretischer Terminologie - nicht in der Lage war, über die Möglichkeit zu sprechen, nahezu alle Menschen zu töten?" Der Fragesteller gehört zu den berühmtesten Physikern des 20. Jahrhunderts und zu den nach wie vor Umstrittensten. über ihn wurde in den 1960er Jahren ein international viel beachtetes Theaterstück geschrieben, vor wenigen Jahren gar eine Oper.

  16. Severe hyponatraemia secondary to desmopressin therapy in von Willebrand's disease.

    PubMed

    Bertholini, D M; Butler, C S

    2000-04-01

    A 42-year-old female with von Willebrand's disease was managed with desmopressin and tranexamic acid to aid haemostasis following a vaginal hysterectomy. Severe acute hyponatraemia (134 to 108 mmol/l) developed over two days, culminating in a generalized tonic-clonic seizure and cerebral oedema. Fluid restriction, cessation of desmopressin and hypertonic saline administration led to a full recovery. Desmopressin is known to reduce free water elimination and produce hyponatraemia, but its extent and rate of development in this patient was surprising. Close monitoring of serum sodium and fluid balance is recommended in these patients.

  17. Dr. von Braun on the Mobility Test Article (MTA)

    NASA Technical Reports Server (NTRS)

    1966-01-01

    In this June 1966 photograph, Marshall Space Flight Center Director Dr. Wernher von Braun test-drives the Mobility Test Article (MTA), a developmental vehicle built by the Bendix Corporation to test lunar mobility vehicle concepts. The data provided by the MTA helped in designing the Lunar Roving Vehicle (LRV), developed under the direction of the MSFC. The LRV was designed to allow Apollo astronauts a greater range of mobility during lunar exploration missions. The LRVs were deployed during the last three Apollo missions; Apollo 15, Apollo 16, and Apollo 17.

  18. Dr. von Braun Driving the Mobility Test Article

    NASA Technical Reports Server (NTRS)

    1966-01-01

    In this June, 1966 photograph, Marshall Space Flight Center Director, Dr. Wernher von Braun test drives the Mobility Test Article (MTA), a developmental vehicle built by the Bendix Corporation to test lunar mobility concepts. The data provided by the MTA helped in designing the Lunar Roving Vehicle (LRV), developed under the direction of the Marshall Space Flight Center. The LRV was designed to allow Apollo astronauts a greater range during lunar exploration missions and served its purpose during the last three Apollo lunar missions in 1971 and 1972.

  19. The Fate of Western Civilization: G. H. von Wright's Reflections on Science, Technology, and Global Society

    ERIC Educational Resources Information Center

    Heikkero, Topi

    2004-01-01

    This article introduces the central ideas of G. H. von Wright's cultural philosophy concerning the techno-scientific form of life. Georg Henrik von Wright (1916-2003) was best known for his achievements in the field of modal logic and for his association with Ludwig Wittgenstein. However, his work also included a critical analysis of science and…

  20. 76 FR 36166 - Culturally Significant Objects Imported for Exhibition; Determinations: “Gabriel von Max: Be...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-21

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition; Determinations: ``Gabriel von Max: Be-Tailed Cousins... the exhibition ``Gabriel von Max: Be-Tailed Cousins and Phantasms of the Soul,'' imported from...

  1. An Alternative Perspective on von Winterfeldt et al.'s (1997) Test of Consequence Monotonicity

    ERIC Educational Resources Information Center

    Ho, Moon-Ho R.; Regenwetter, Michel; Niederee, Reinhard; Heyer, Dieter

    2005-01-01

    D. von Winterfeldt, N.-K. Chung, R. D. Luce, and Y. Cho (see record 1997-03378-008) provided several tests for consequence monotonicity of choice or judgment, using certainty equivalents of gambles. The authors reaxiomatized consequence monotonicity in a probabilistic framework and reanalyzed von Winterfeldt et al.'s main experiment via a…

  2. Public information needs after the poisoning of Alexander Litvinenko with polonium-210 in London: cross sectional telephone survey and qualitative analysis

    PubMed Central

    Page, Lisa; Morgan, Oliver; Pinder, Richard J; Riley, Paul; Hatch, Stephani; Maguire, Helen; Catchpole, Mike; Simpson, John; Wessely, Simon

    2007-01-01

    Objectives To identify public perceptions of the risk to health after the poisoning of Alexander Litvinenko with polonium-210 (210Po) in London and to assess the impact of public health communications. Design Cross sectional telephone survey and qualitative interviews. Setting London, United Kingdom. Participants 1000 people completed the cross sectional survey and 86 potentially exposed people completed the qualitative interviews. Main outcome measures Perception of risk to personal health after the 210Po incident. Qualitative interviews were analysed with an emphasis on information needs. Results 11.7% of the survey sample (n=117) perceived their health to be at risk. Aside from personal variables the main predictors of perceived risk to health were believing that the incident was related to terrorism (odds ratio 2.7, 95% confidence interval 1.5 to 4.6) rather than to espionage, that it was targeted at the wider public rather than one person (5.9, 3.2 to 10.9), and that it could affect people who had not been in the contaminated area (3.2, 2.1 to 5.1). Participants in the qualitative interviews were generally satisfied with the information they had received, although they would have preferred more information about their individual risk of exposure, the results of their urine tests, and the health implications of the incident. Conclusions Perceptions of the public that the 210Po incident in London in 2006 was related to espionage helped to reassure them that the risks to personal health were low. In the event of future incidents it is important to ensure that detailed, comprehensible information about the risks of any exposure is available. PMID:17975252

  3. von Baer's law for the ages: lost and found principles of developmental evolution.

    PubMed

    Abzhanov, Arhat

    2013-12-01

    In 1828, Karl Ernst von Baer formulated a series of empirically defined rules, which became widely known as the 'Law of Development' or 'von Baer's law of embryology'. This was one the most significant attempts to define the principles that connected morphological complexity and embryonic development. Understanding this relation is central to both evolutionary biology and developmental genetics. Von Baer's ideas have been both a source of inspiration to generations of biologists and a target of continuous criticism over many years. With advances in multiple fields, including paleontology, cladistics, phylogenetics, genomics, and cell and developmental biology, it is now possible to examine carefully the significance of von Baer's law and its predictions. In this review, I argue that, 185 years after von Baer's law was first formulated, its main concepts after proper refurbishing remain surprisingly relevant in revealing the fundamentals of the evolution-development connection, and suggest that their explanation should become the focus of renewed research.

  4. Karl ernst von Baer's 'Uber Entwickelungsgeschichte der Thiere II' and its unpublished drawings.

    PubMed

    Tammiksaar, Erki; Brauckmann, Sabine

    2004-01-01

    In 1828 Karl Ernst von Baer (1792-1876) published his seminal Uber Entwickelungsgeschichte der Thiere. Beobachtung und Reflexion. In the preface he announced that a second volume with one copper plate would be finished 'in a few weeks'. However, it took nine years until the unfinished second volume was released, with four copperplates. In his 'Autobiography', von Baer did not clarify the reasons why he did not finish his research program of comparative embryology. The paper attempts to elucidate them, furnished by archival documents and von Baer's unpublished embryological drawings. Our sketch of a few figures will show that (1) von Baer searched for 'analogies' (homologies) as a unifying principle and (2) explained the mechanisms of embryogenesis by physiological reasoning (electromagnetism). The main objective is to show that technical problems in illustrating and conceptual difficulties impeded von Baer's ambitious research program.

  5. Von Willebrand factor and angiogenesis: basic and applied issues.

    PubMed

    Randi, A M; Laffan, M A

    2017-01-01

    The recent discovery that von Willebrand factor (VWF) regulates blood vessel formation has opened a novel perspective on the function of this complex protein. VWF was discovered as a key component of hemostasis, capturing platelets at sites of endothelial damage and synthesized in megakaryocytes and endothelial cells (EC). In recent years, novel functions and binding partners have been identified for VWF. The finding that loss of VWF in EC results in enhanced, possibly dysfunctional, angiogenesis is consistent with the clinical observations that in some patients with von Willebrand disease (VWD), vascular malformations can cause severe gastrointestinal (GI) bleeding. In vitro and in vivo studies indicate that VWF can regulate angiogenesis through multiple pathways, both intracellular and extracellular, although their relative importance is still unclear. Investigation of these pathways has been greatly facilitated by the ability to isolate EC from progenitors circulating in the peripheral blood of normal controls and patients with VWD. In the next few years, these will yield further evidence on the molecular pathways controlled by VWF and shed light on this novel and fascinating area of vascular biology. In this article, we will review the evidence supporting a role for VWF in blood vessel formation, the link between VWF dysfunction and vascular malformations causing GI bleeding and how they may be causally related. Finally, we will discuss how these findings point to novel therapeutic approaches to bleeding refractory to VWF replacement therapy in VWD.

  6. Interaction of the von Willebrand factor with platelets and thrombosis.

    PubMed

    Perutelli, P; Mori, P G

    1997-11-01

    The human von Willebrand factor (vWf) is a multimeric glycoprotein present in plasma, platelets, endothelial cells and subendothelium and synthesized in endothelial cells and megakaryocytes. vWf plays a pivotal role in the mechanisms of blood clotting and platelet thrombus formation; quantitative and qualitative abnormalities of vWf cause the most common congenital bleeding disorder in man, the von Willebrand disease. vWf stabilizes factor VIII and interacts with subendothelial components and with platelet membrane receptors. The multimeric structure of vWf provides an array of binding sites which allows multivalent interactions with its ligands, thus supporting the formation of stable platelet aggregates at the site of vascular injury, particularly under flow conditions characterized by high shear stress. In the last years, remarkable progress has been made toward understanding the structure of vWf protein and gene, and the elucidation of many structure-function relationships, which may result in improved therapeutic intervention for vWD patients, and in the development of effective strategies for antithrombotic therapy.

  7. Von Braun Rocket Team at Fort Bliss, Texas

    NASA Technical Reports Server (NTRS)

    1940-01-01

    The German Rocket Team, also known as the Von Braun Rocket Team, poses for a group photograph at Fort Bliss, Texas. After World War II ended in 1945, Dr. Wernher von Braun led some 120 of his Peenemuende Colleagues, who developed the V-2 rocket for the German military during the War, to the United Sttes under a contract to the U.S. Army Corps as part of Operation Paperclip. During the following five years the team worked on high altitude firings of the captured V-2 rockets at the White Sands Missile Range in New Mexico, and a guided missile development unit at Fort Bliss, Texas. In April 1950, the group was transferred to the Army Ballistic Missile Agency (ABMA) at Redstone Arsenal in Huntsville, Alabama, and continued to work on the development of the guided missiles for the U.S. Army until transferring to a newly established field center of the National Aeronautic and Space Administration (NASA), George C. Marshall Space Flight Center (MSFC).

  8. von Willebrand factor, Jedi knight of the bloodstream.

    PubMed

    Springer, Timothy A

    2014-08-28

    When blood vessels are cut, the forces in the bloodstream increase and change character. The dark side of these forces causes hemorrhage and death. However, von Willebrand factor (VWF), with help from our circulatory system and platelets, harnesses the same forces to form a hemostatic plug. Force and VWF function are so closely intertwined that, like members of the Jedi Order in the movie Star Wars who learn to use "the Force" to do good, VWF may be considered the Jedi knight of the bloodstream. The long length of VWF enables responsiveness to flow. The shape of VWF is predicted to alter from irregularly coiled to extended thread-like in the transition from shear to elongational flow at sites of hemostasis and thrombosis. Elongational force propagated through the length of VWF in its thread-like shape exposes its monomers for multimeric binding to platelets and subendothelium and likely also increases affinity of the A1 domain for platelets. Specialized domains concatenate and compact VWF during biosynthesis. A2 domain unfolding by hydrodynamic force enables postsecretion regulation of VWF length. Mutations in VWF in von Willebrand disease contribute to and are illuminated by VWF biology. I attempt to integrate classic studies on the physiology of hemostatic plug formation into modern molecular understanding, and point out what remains to be learned.

  9. The von Neumann model of measurement in quantum mechanics

    SciTech Connect

    Mello, Pier A.

    2014-01-08

    We describe how to obtain information on a quantum-mechanical system by coupling it to a probe and detecting some property of the latter, using a model introduced by von Neumann, which describes the interaction of the system proper with the probe in a dynamical way. We first discuss single measurements, where the system proper is coupled to one probe with arbitrary coupling strength. The goal is to obtain information on the system detecting the probe position. We find the reduced density operator of the system, and show how Lüders rule emerges as the limiting case of strong coupling. The von Neumann model is then generalized to two probes that interact successively with the system proper. Now we find information on the system by detecting the position-position and momentum-position correlations of the two probes. The so-called 'Wigner's formula' emerges in the strong-coupling limit, while 'Kirkwood's quasi-probability distribution' is found as the weak-coupling limit of the above formalism. We show that successive measurements can be used to develop a state-reconstruction scheme. Finally, we find a generalized transform of the state and the observables based on the notion of successive measurements.

  10. von Willebrand disease: advances in pathogenetic understanding, diagnosis, and therapy.

    PubMed

    Lillicrap, David

    2013-01-01

    von Willebrand disease (VWD) is the most common autosomally inherited bleeding disorder. The disease represents a range of quantitative and qualitative pathologies of the adhesive glycoprotein von Willebrand factor (VWF). The pathogenic mechanisms responsible for the type 2 qualitative variants of VWF are now well characterized, with most mutations representing missense substitutions influencing VWF multimer structure and interactions with platelet GPIbα and collagen and with factor VIII. The molecular pathology of type 3 VWD has been similarly well characterized, with an array of different mutation types producing either a null phenotype or the production of VWF that is not secreted. In contrast, the pathogenetic mechanisms responsible for type 1 VWD remain only partially resolved. In the hemostasis laboratory, the measurement of VWF:Ag and VWF:RCo are key components in the diagnostic algorithm for VWD, although the introduction of direct GPIbα-binding assays may become the functional assay of choice. Molecular genetic testing can provide additional benefit, but its utility is currently limited to type 2 and 3 VWD. The treatment of bleeding in VWD involves the use of desmopressin and plasma-derived VWF concentrates and a variety of adjunctive agents. Finally, a new recombinant VWF concentrate has just completed clinical trial evaluation and has demonstrated excellent hemostatic efficacy and safety.

  11. Developments in the diagnostic procedures for von Willebrand disease.

    PubMed

    De Jong, A; Eikenboom, J

    2016-03-01

    Von Willebrand disease (VWD) is the most common inherited bleeding disorder but its diagnosis can be challenging due to the heterogeneity of the disease. VWD is mainly associated with mild mucocutaneous bleeding, although there are more severe phenotypes with bleeding from the gastrointestinal tract or even the joints. Also, surgical interventions and trauma may lead to critical bleeding events. These bleeding episodes are all related to quantitative or qualitative defects of von Willebrand factor (VWF), a multimeric glycoprotein produced by endothelial cells and megakaryocytes, which mediates platelet adhesion and aggregation and binds factor VIII (FVIII) in the circulation. This review describes the diagnostic procedures required for correct diagnosis. Accurate diagnosis and classification is required for proper treatment and counseling. Assessment of bleeding starts with the medical history. After a positive bleeding or family history, subsequent laboratory investigations will start with a panel of standard screening tests for hemostatic defects. Patients suspected of having VWD will be tested for plasma VWF antigen levels, the ability of VWF to bind platelets and FVIII activity. When VWD is confirmed, a set of subtyping tests can classify the patients as VWD types 1, 2 (A, B, M or N) or 3. The performance of some additional assays and analyses, such as VWF propeptide measurement or genetic analysis, may help in identifying the pathological mechanism behind certain defects or can guide in the choice of treatment.

  12. Prophylaxis in von Willebrand Disease: Coming of Age?

    PubMed

    Saccullo, Giorgia; Makris, Mike

    2016-07-01

    Although in most cases von Willebrand disease (VWD) is a mild disorder, a subgroup of patients experience frequent bleeding. In contrast to severe hemophilia in which prophylaxis is the accepted standard of care, this is less frequently used in VWD. Most type 1 VWD patients can be adequately managed with episodic desmopressin and tranexamic acid. In patients with more severe disease, especially those with type 3 VWD, joint bleeds, epistaxis, menorrhagia, and gastrointestinal bleeding are problematic and usually require treatment with von Willebrand factor/factor VIII (VWF/FVIII) concentrate. While in the past these patients were managed with on-demand VWF/FVIII concentrate, several recent reports have demonstrated the value of prophylactic treatment. Despite some uncertainties about the economic impact of treatment of severe VWD, prophylaxis with VWF concentrate should now be considered as the standard of care for the more severe end of the spectrum of affected individuals. The recent introduction of recombinant VWF concentrate is likely to improve the acceptability of prophylaxis in VWD.

  13. Acquired von Willebrand syndrome in patients with Gaucher disease.

    PubMed

    Mitrovic, Mirjana; Elezovic, Ivo; Miljic, Predrag; Suvajdzic, Nada

    2014-04-01

    Although various coagulation abnormalities occur in patients with Gaucher disease (GD), von Willebrand factor (vWF) deficiency has rarely been reported. A retrospective review of six treatment naïve cases with GD and concomitant vWF deficiency over a 12-year-period in a single center is presented. All patients had a personal history of prior hemorrhages. Based on both reduced level of vWF antigen (vWF:Ag, range 14-56%) and ristocetin cofactor activity (vWF:RCo, range 12-53%), with a vWF:RCo/Ag ratio >0.7, the diagnosis of type 1 von Willebrand disease was made in all six cases. During enzyme replacement therapy (ERT) of a 2-year duration all patients normalized their vWF:Ag levels. Based on the positive ERT effect on vWF:Ag levels, vWF deficiency was assumed to be acquired. It should be noted that beside vWF deficiency four patients with GD exhibited mild thrombocytopenia (range 81-131×10(9)/L) and three had additional hemostatic defects (reduced collagen platelet aggregation, FV, FXI and FXII deficiencies).

  14. A visit paid to Jung by Alwine von Keller.

    PubMed

    Bernardini, Riccardo; Quaglino, Gian Piero; Romano, Augusto

    2011-04-01

    In the winter of 1943-1944, Jung had suffered a coronary thrombosis which almost cost him his life. During his illness, Jung experienced a series of visions, described in his Memories, Dreams, Reflections, which were also to influence significantly the development of his theoretical thinking. On 27(th) September 1944, Alwine von Keller (1878-1965) paid a visit to Jung, while he was still convalescing, in Zurich and documented her meeting with him in a series of notes, recently discovered, which testify to the fact that, at the time of their meeting, Jung was engaged in writing the 'Salt' chapter of Mysterium coniunctionis and investigating the alchemistic symbolism of the 'sea'. This theme seems to testify to a continuity of interests on Jung's part with the seminar he held at Eranos the previous year on the cartographic art of Opicinus de Canistris (1296-c.1352). With its addition of many unpublished details, Alwine von Keller's notes supplement the report which Jung made of his visions experienced during his sickness in MDR. In particular, these attest to the fact that Jung had attributed the terrible experience which he had endured to the problem of the conjunctio, which was confronting him from the theoretical point of view in his writing of Mysterium coniunctionis.

  15. Visualizing the von Willebrand factor/glycoprotein Ib-IX axis with a platelet-type von Willebrand disease mutation.

    PubMed

    Guerrero, Jose A; Kyei, Mark; Russell, Susan; Liu, Junling; Gartner, T Kent; Storrie, Brian; Ware, Jerry

    2009-12-24

    Platelet-type von Willebrand disease (PT-VWD) is a bleeding disorder of the platelet glycoprotein Ib-IX/von Willebrand factor (VWF) axis caused by mutations in the glycoprotein Ib-IX receptor that lead to an increased affinity with VWF. In this report, platelets from a mouse expressing a mutation associated with PT-VWD have been visualized using state-of-the art image collection and processing. Confocal analysis revealed that VWF bound to the surface of single platelets and bridging micro-aggregates of platelets. Surface-bound VWF appears as a large, linear structure on the surface of 50% of the PT-VWD platelets. In vivo thrombus formation after chemical injury to the carotid artery revealed a severe impairment to occlusion as a consequence of the PT-VWD mutation. In vitro stimulation of PT-VWD platelets with adenosine diphosphate or thrombin demonstrates a significant block in their ability to bind fibrinogen. The impairment of in vivo thrombus formation and in vitro fibrinogen binding are more significant than might be expected from the observed platelet binding to VWF polymers over a small portion of the plasma membrane. Visualization of the receptor/ligand interaction and characterization of a severe antithrombotic phenotype provide a new understanding on the molecular basis of bleeding associated with the PT-VWD phenotype.

  16. Variable content of von Willebrand factor mutant monomer drives the phenotypic variability in a family with von Willebrand disease.

    PubMed

    Chen, Junmei; Hinckley, Jesse D; Haberichter, Sandra; Jacobi, Paula; Montgomery, Robert; Flood, Veronica H; Wong, Randall; Interlandi, Gianluca; Chung, Dominic W; López, José A; Di Paola, Jorge

    2015-07-09

    Von Willebrand disease (VWD) is an inherited bleeding disorder characterized by incomplete penetrance and variable expressivity. We evaluated a 24-member pedigree with VWD type 2 caused by a T>G mutation at position 3911 that predicts a methionine to arginine (M1304R) change in the platelet-binding A1 domain of von Willebrand factor (VWF). This mutation manifests as an autosomal-dominant trait, with clinical and biochemical phenotypic variability among affected individuals, including differences in bleeding tendency and VWF quantity, activity, and multimer pattern. Sequencing of all VWF coding regions in 3 affected individuals did not identify additional mutations. When expressed in heterologous cells, M1304R was secreted in lower quantities, failed to drive formation of storage granules, and was defective in multimerization and platelet binding. When cotransfected in equal quantities with the wild-type complementary DNA, the mutant complementary DNA depressed VWF secretion, although multimerization was only mildly affected. A llama nanobody (AU/VWFa-11) that detects the mutant A1 domain demonstrated highly variable binding to VWF from different affected members, indicating that the VWF contained different percentages of mutant monomers in different individuals. Thus, the observed variability in VWD phenotypes could in part be determined by the extent of mutant monomer incorporation in the final multimer structure of plasma VWF.

  17. Platelet-independent adhesion of calcium-loaded erythrocytes to von Willebrand factor

    PubMed Central

    Bierings, Ruben; Meems, Henriet; Mul, Frederik P. J.; Geerts, Dirk; Vlaar, Alexander P. J.; Voorberg, Jan; Hordijk, Peter L.

    2017-01-01

    Adhesion of erythrocytes to endothelial cells lining the vascular wall can cause vaso-occlusive events that impair blood flow which in turn may result in ischemia and tissue damage. Adhesion of erythrocytes to vascular endothelial cells has been described in multiple hemolytic disorders, especially in sickle cell disease, but the adhesion of normal erythrocytes to endothelial cells has hardly been described. It was shown that calcium-loaded erythrocytes can adhere to endothelial cells. Because sickle erythrocyte adhesion to ECs can be enhanced by ultra-large von Willebrand factor multimers, we investigated whether calcium loading of erythrocytes could promote binding to endothelial cells via ultra-large von Willebrand factor multimers. We used (immunofluorescent) live-cell imaging of washed erythrocytes perfused over primary endothelial cells at venular flow rate. Using this approach, we show that calcium-loaded erythrocytes strongly adhere to histamine-stimulated primary human endothelial cells. This adhesion is mediated by ultra-large von Willebrand factor multimers. Von Willebrand factor knockdown or ADAMTS13 cleavage abolished the binding of erythrocytes to activated endothelial cells under flow. Platelet depletion did not interfere with erythrocyte binding to von Willebrand factor. Our results reveal platelet-independent adhesion of calcium-loaded erythrocytes to endothelium-derived von Willebrand factor. Erythrocyte adhesion to von Willebrand factor may be particularly relevant for venous thrombosis, which is characterized by the formation of erythrocyte-rich thrombi. PMID:28249049

  18. Is the activated partial thromboplastin time suitable to screen for von Willebrand factor deficiencies?

    PubMed

    Lippi, Giuseppe; Franchini, Massimo; Poli, Giovanni; Salvagno, Gian Luca; Montagnana, Martina; Guidi, Gian Cesare

    2007-06-01

    The diagnostic approach to von Willebrand factor deficiencies is challenging and requires discretionary use of laboratory resources. Although extensive preoperative testing is not recommended, the activated partial thromboplastin time may be useful, especially in selected categories of patients. To establish the diagnostic sensitivity of this test to identify isolate von Willebrand factor deficiencies, 204 consecutive patients underwent a routine preoperative screening consisting of activated partial thromboplastin time, von Willebrand factor antigen, intrinsic pathway clotting factors activity, lupus anticoagulants and thrombin time. Thirty-seven patients were diagnosed with haemostasis disturbances other than von Willebrand factor deficiencies and were excluded from the evaluation. Isolated von Willebrand factor deficiency was diagnosed in 11 of the remaining 167 patients. A significant correlation was observed between von Willebrand factor antigen and activated partial thromboplastin time. Receiver operating characteristic curve analysis showed an area under the curve of 0.982 (95% confidence interval: 0.972-0.992; P < 0.001). At the 1.17 upper limit of the activated partial thromboplastin time, sensitivity and specificity were 100 and 85%, respectively, with negative and positive predictive values of 100 and 31%, respectively. These results demonstrate that activated partial thromboplastin time has an excellent diagnostic sensitivity and a satisfactory specificity for identifying isolated von Willebrand factor deficiencies.

  19. Observatoriya imeni russkogo astronoma v dalekoj Brazilii. K 100-letiyu so diya rozhdeniya Aleksandra Ivanovicha Postoeva (1900 - 1976) %t An observatory in distant Brazil named after a Russian astronomer (dedicated to Alexander Postoyev (1900 - 1976) centennial anniversary

    NASA Astrophysics Data System (ADS)

    Marques Dos Santos, P.; Matsuura, O. T.

    This is a biographical note on the life of Dr. Alexander Postoyev, a victim of Stalin's purge of Soviet astronomers in 1936 - 1937. Together with his family, he left the Soviet Union in 1943 and lived in Germany as a refugee and a "displaced person" until 1952, when he moved to Brazil. There, he started the second part of his professional career. Thanks to his efforts, the Astronomical and Geophysical Institute (IAG) of the University of Sao Paulo (USP) was for the first time included in programs of international cooperation, thus contributing to the institutional consolidation of IAG/USP as a leading center of astronomical research and teaching in Brazil now.

  20. von Willebrand factor binds to the surface of dendritic cells and modulates peptide presentation of factor VIII

    PubMed Central

    Sorvillo, Nicoletta; Hartholt, Robin B.; Bloem, Esther; Sedek, Magdalena; Brinke, Anja ten; van der Zwaan, Carmen; van Alphen, Floris P.; Meijer, Alexander B.; Voorberg, Jan

    2016-01-01

    It has been proposed that von Willebrand factor might affect factor VIII immunogenicity by reducing factor VIII uptake by antigen presenting cells. Here we investigate the interaction of recombinant von Willebrand factor with immature monocyte-derived dendritic cells using flow cytometry and confocal microscopy. Surprisingly, von Willebrand factor was not internalized by immature dendritic cells, but remained bound to the cell surface. As von Willebrand factor reduces the uptake of factor VIII, we investigated the repertoire of factor VIII presented peptides when in complex with von Willebrand factor. Interestingly, factor VIII-derived peptides were still abundantly presented on major histocompatibility complex class II molecules, even though a reduction of factor VIII uptake by immature dendritic cells was observed. Inspection of peptide profiles from 5 different donors showed that different core factor VIII peptide sequences were presented upon incubation with factor VIII/von Willebrand factor complex when compared to factor VIII alone. No von Willebrand factor peptides were detected when immature dendritic cells were pulsed with different concentrations of von Willebrand factor, confirming lack of von Willebrand factor endocytosis. Several von Willebrand factor derived peptides were recovered when cells were pulsed with von Willebrand factor/factor VIII complex, suggesting that factor VIII promotes endocytosis of small amounts of von Willebrand factor by immature dendritic cells. Taken together, our results establish that von Willebrand factor is poorly internalized by immature dendritic cells. We also show that von Willebrand factor modulates the internalization and presentation of factor VIII-derived peptides on major histocompatibility complex class II. PMID:26635035

  1. Evaluating return on investment in a school based health promotion and prevention program: the investment multiplier for the Stephanie Alexander Kitchen Garden National Program.

    PubMed

    Eckermann, Simon; Dawber, James; Yeatman, Heather; Quinsey, Karen; Morris, Darcy

    2014-08-01

    Successful health promotion and disease prevention strategies in complex community settings such as primary schools rely on acceptance and ownership across community networks. Assessing multiplier impacts from investment on related community activity over time are suggested as key alongside evidence of program health effects on targeted groups of individuals in gauging community network engagement and ownership, dynamic impacts, and program long term success and return on investment. An Australian primary school based health promotion and prevention strategy, the Stephanie Alexander Kitchen Garden National Program (SAKGNP), which has been providing garden and kitchen classes for year 3-6 students since 2008, was evaluated between 2011 and 2012. Returns on Australian Federal Government investment for school infrastructure grants up to $60,000 are assessed up to and beyond a two year mutual obligation period with: (i) Impacts on student lifestyle behaviours, food choices and eating habits surveyed across students (n = 491 versus 260) and parents (n = 300 versus 234) in 28 SAKGNP and 14 matched schools, controlling for school and parent level confounders and triangulated with SAKGNP pre-post analysis; (ii) Multiplier impacts of investment on related school and wider community activity up to two years; and (iii) Evidence of continuation and program evolution in schools observed beyond two years. SAKGNP schools showed improved student food choices (p = 0.024) and kitchen lifestyle behaviour (p = 0.019) domains compared to controls and in pre-post analysis where 20.0% (58/290) reported eating fruit and vegetables more often and 18.6% (54/290) preparing food at home more often. No significant differences were found in case control analysis for eating habits or garden lifestyle behaviour domains, although 32.3% of children helped more in the garden (91/278) and 15.6% (45/289) ate meals together more often in pre-post analysis. The multiplier impact on total

  2. [Ernst von der Porten : looking for facts before and after forced emigration].

    PubMed

    Goerig, M; Bruijn, L

    2014-10-01

    The Ernst von der Porten medal has been awarded for many years to exceptional personalities by the Alliance of German Anesthesiologists to honor the outstanding achievements of the physician Ernst von der Porten from Hamburg in the development of anesthesiology as an autonomous discipline Only recent access to hitherto inaccessible documents enabled the reconstruction of his final years. He was persecuted and excluded by the National Socialist (NS) regime due to his Jewish roots and finally forced to emigrate. Records revealed that even in the so-called safe exile, degrading treatment and humiliation continued for Ernst von der Porten and his family. He eventually evaded this situation by committing suicide.

  3. The role of von Willebrand factor in thrombus formation.

    PubMed

    Ruggeri, Zaverio M

    2007-01-01

    Von Willebrand factor (VWF) is a large multimeric glycoprotein produced in endothelial cells and megakaryocytes and present in subendothelial matrix, blood plasma and platelets. VWF mediates adhesion and aggregation of platelets at sites of vascular injury, processes that are critical for both haemostasis and thrombosis. Thrombus formation involves complex events that are influenced by different environmental conditions. Progress in understanding the structure and function of VWF and the mechanisms that underlie its interactions with platelets has led to important insight into the differentiation between normal haemostasis and pathological arterial thrombosis. The conventional view of signalling-induced platelet aggregation has recently been extended to include activation-independent aggregation. A novel mechanism has been demonstrated for initiating thrombus formation under high haemodynamic forces that involves alpha(IIb)beta(3)-independent platelet aggregation at the interface between immobilised and soluble VWF. This VWF-mediated process may be a key determinant of platelet accumulation in stenotic arteries leading to acute thrombotic occlusion.

  4. A Powerful Friendship: Theodore von Karman and Hugh L. Dryden

    NASA Technical Reports Server (NTRS)

    Gorn, Michael

    2003-01-01

    During their long personal friendship and professional association, Theodore von Karman (1882-1963) and Hugh L. Dryden (1898-1965) exercised a pivotal if somewhat elusive influence over American aeronautics and spaceflight. Both decisive figures in organizing scientists and engineers at home and abroad, both men of undisputed eminence in their technical fields, their range of contacts in government, academia, the armed forces, industry, and professional societies spanned the globe to an extent unparalleled then as now. Moreover, because they coordinated their activities closely, their combined influence far exceeded the sum of each one s individual contributions. This paper illustrates their personal origins as well as the foundations of their friendship, how their relationship became a professional alliance, and their joint impact on the world of aeronautics and astronautics during the twentieth century.

  5. Using genetic diagnostics in hemophilia and von Willebrand disease.

    PubMed

    Swystun, Laura L; James, Paula

    2015-01-01

    Most bleeding disorders encountered in clinical practice will be diagnosed, at least initially, by phenotypic assays. However, since the characterization of the genes that encode coagulation factors in the 1980s, significant progress has been made in translating this knowledge for diagnostic and therapeutic purposes. For hemophilia A and B, molecular genetic testing to determine carrier status, prenatal diagnosis, and likelihood of inhibitor development or anaphylaxis to infused coagulation factor concentrates is an established component of comprehensive clinical management. In contrast, although significant recent advances in our understanding of the molecular genetic basis of von Willebrand disease (VWD) have allowed for the development of rational approaches to genetic diagnostics, questions remain about this complex genetic disorder and how to incorporate emerging knowledge into diagnostic strategies. This article will review the state-of-the-art for molecular diagnostics for both hemophilia and VWD.

  6. Voluntarism in early psychology: the case of Hermann von Helmholtz.

    PubMed

    De Kock, Liesbet

    2014-05-01

    The failure to recognize the programmatic similarity between (post-)Kantian German philosophy and early psychology has impoverished psychology's historical self-understanding to a great extent. This article aims to contribute to recent efforts to overcome the gaps in the historiography of contemporary psychology, which are the result of an empiricist bias. To this end, we present an analysis of the way in which Hermann von Helmholtz's theory of perception resonates with Johann Gottlieb Fichte's Ego-doctrine. It will be argued that this indebtedness is particularly clear when focusing on the foundation of the differential awareness of subject and object in perception. In doing so, the widespread reception of Helmholtz's work as proto-positivist or strictly empiricist is challenged, in favor of the claim that important elements of his theorizing can only be understood properly against the background of Fichte's Ego-doctrine.

  7. Von Glaserfeld`s Radical Constructivism: A Critical Review

    NASA Astrophysics Data System (ADS)

    Hardy, Michael D.

    We explore Ernst von Glaserfelds radical constructivism, its criticisms, and our own thoughts on what it promises for the reform of science and mathematics teaching. Our investigation reveals that many criticisms of radical constructivism are unwarranted; nevertheless, in its current cognitivist form radical constructivism may be insufficient to empower teachers to overcome objectivist cultural traditions. Teachers need to be empowered with rich understandings of philosophies of science and mathematics that endorse relativist epistemologies; for without such they are unlikely to be prepared to reconstruct their pedagogical practices. More importantly, however, is a need for a powerful social epistemology to serve as a referent for regenerating the culture of science education. We recommend blending radical constructivism with Habermas theory of communicative action to provide science teachers with a moral imperative for adopting a constructivist epistemology.

  8. ADAMTS13 and von Willebrand factor in thrombotic thrombocytopenic purpura.

    PubMed

    Zheng, X Long

    2015-01-01

    Pathogenesis of thrombotic thrombocytopenic purpura (TTP) was a mystery for over half a century until the discovery of ADAMTS13. ADAMTS13 is primarily synthesized in the liver, and its main function is to cleave von Willebrand factor (VWF) anchored on the endothelial surface, in circulation, and at the sites of vascular injury. Deficiency of plasma ADAMTS13 activity (<10%) resulting from mutations of the ADAMTS13 gene or autoantibodies against ADAMTS13 causes hereditary or acquired (idiopathic) TTP. ADAMTS13 activity is usually normal or modestly reduced (>20%) in other forms of thrombotic microangiopathy secondary to hematopoietic progenitor cell transplantation, infection, and disseminated malignancy or in hemolytic uremic syndrome. Plasma infusion or exchange remains the initial treatment of choice to date, but novel therapeutics such as recombinant ADAMTS13 and gene therapy are under development. Moreover, ADAMTS13 deficiency has been shown to be a risk factor for the development of myocardial infarction, stroke, cerebral malaria, and preeclampsia.

  9. Stochastic resonance in a generalized Von Foerster population growth model

    SciTech Connect

    Lumi, N.; Mankin, R.

    2014-11-12

    The stochastic dynamics of a population growth model, similar to the Von Foerster model for human population, is studied. The influence of fluctuating environment on the carrying capacity is modeled as a multiplicative dichotomous noise. It is established that an interplay between nonlinearity and environmental fluctuations can cause single unidirectional discontinuous transitions of the mean population size versus the noise amplitude, i.e., an increase of noise amplitude can induce a jump from a state with a moderate number of individuals to that with a very large number, while by decreasing the noise amplitude an opposite transition cannot be effected. An analytical expression of the mean escape time for such transitions is found. Particularly, it is shown that the mean transition time exhibits a strong minimum at intermediate values of noise correlation time, i.e., the phenomenon of stochastic resonance occurs. Applications of the results in ecology are also discussed.

  10. Terminal platelet production is regulated by von Willebrand factor.

    PubMed

    Poirault-Chassac, Sonia; Nguyen, Kim Anh; Pietrzyk, Audrey; Casari, Caterina; Veyradier, Agnes; Denis, Cecile V; Baruch, Dominique

    2013-01-01

    It is established that proplatelets are formed from mature megakaryocytes (MK) as intermediates before platelet production. Recently, the presence of proplatelets was described in blood incubated in static conditions. We have previously demonstrated that platelet and proplatelet formation is upregulated by MK exposure to high shear rates (1800 s(-1)) on immobilized von Willebrand factor (VWF). The purpose of the present study was to investigate whether VWF is involved in the regulation of terminal platelet production in blood. To this end, Vwf (-/-) mice, a model of severe von Willebrand disease, were used to create a situation in which blood cells circulate in a vascular tree that is completely devoid of VWF. Murine platelets were isolated from Vwf (-/-) and Vwf (+/+) blood, exposed to VWF at 1800 s(-1) in a microfluidic platform, and examined by means of videomicroscopy, as well as fluorescence and activation studies. Proplatelets became visible within 5 minutes, representing 38% of all platelets after 12 minutes and 46% after 28 min. The proportion of proplatelets was 1.8-fold higher in blood from Vwf(-/-) mice than from Vwf(+/+) mice, suggesting a role of VWF in vivo. Fragmentation of these proplatelets into smaller discoid platelets was also observed in real-time. Platelets remained fully activatable by thrombin. Compensation of plasmatic VWF following hydrodynamic gene transfer in Vwf(-/-) mice reduced the percentage of proplatelets to wild-type levels. A thrombocytopenic mouse model was studied in the flow system, 7 days after a single 5-FU injection. Compared to untreated mouse blood, a 2-fold increase in the percentage of proplatelets was detected following exposure to 1800 s(-1) on VWF of samples from mice treated with 5-FU. In conclusion, VWF and shear stress together appear to upregulate proplatelet reorganization and platelet formation. This suggests a new function for VWF in vivo as regulator of bloodstream thrombopoiesis.

  11. [Reference relationships between human and animal in Hildegard von Bingen].

    PubMed

    Riethe, Peter

    2012-01-01

    In "De animalibus", the 7th book in the "Liber simplicis medicinae", Hildegard von Bingen describes the characteristics of four-footed land animals. Some of these have a special relationship with humans in that they embody moral qualities. An explanation for this is already given in the preface, which states that human intelligence recognizes these qualities, declaring that "You are this or that sort of creature". Since the relationship that animals have with nature shares a degree of similarity with that of man's, they can be regarded as symbolic representatives for particular human traits and characteristics. The article at hand presents Hildegard von Bingen's descriptions of the monkey, the lion, the bear, the rabbit, the dog, the cat, the wolf, the lynx, and the donkey. While the monkey just mimics man's behaviour and is imperfect in both settings, the lion embodies will power. The bear on the other hand stands for unbridled sexual desire, while in the rabbit the gentleness of a sheep is united with the bounce of a deer. The lynx is regarded as hedonistic, the donkey as stupid, and the wolf as surrounded by dangerous sylphs. In Hildegard's depictions, exotic and native animal species display rather extraordinary behavioural traits, and the medieval Christian world view of the author conveys unexpected relationships between humans and animals. In addition to empirical observation and experience, Hildegard also relies on folkloristic beliefs and magical practices related to explanatory models of her time. She allows largely unknown sources into her animal lore but never strays from her ultimate goal of having it serve to instruct people. In doing so, Hildegard removed herself far from the common tradition of medieval animal portraits.

  12. Acquired von Willebrand syndrome in children with aorticand pulmonary stenosis

    PubMed Central

    Binnetoğlu, Fatih Köksal; Babaoğlu, Kadir; Filiz, Şayegan Güven; Zengin, Emine; Sarper, Nazan; Altun, Gürkan; Kılıç, Suar Çakı

    2016-01-01

    Summary Introduction: This prospective study was planned to investigate the frequency and relationship of acquired von Willebrand syndrome (AVWS) with aortic and pulmonary stenosis in patients. Methods: A total of 84 children, ranging from two to 18 years of age, were enrolled in this study. Of these, 28 had isolated aortic stenosis, 32 had isolated pulmonary stenosis and 24 were healthy. Children with aortic and pulmonary stenosis associated with other congenital heart diseases were excluded. Children with hypothyroidism, renal or liver disease, malignancy or autoimmune disease were also excluded. Wholeblood count, blood group, factor VIII level, prothrombin time (PT), activated partial thromboplastin time (aPTT), von Willebrand factor antigen (VWF:Ag), ristocetin co-factor (VWF:RCo), and bleeding time using a platelet-function analyser (PFA-100) were performed in all patients. All of the children in the study underwent a detailed physical examination and echocardiographic evaluation. Results: A history of bleeding was positive in 18% of the aortic stenosis group, 9% of the pulmonary stenosis group, and 4% of the control group. Seven of 60 (12%) patients had laboratory findings that implied a diagnosis of AVWS, and two of these (28%) had a history of bleeding. The frequency of AVWS was 14% in patients with aortic stenosis and 9% in those with pulmonary stenosis. Conclusion: AVWS is not rare in stenotic obstructive cardiac diseases. A detailed history of bleeding should be taken from patients with valvular disease. Even if the history is negative, whole blood count, PT and aPTT should be performed. If necessary, PFA-100 closure time and further tests should be planned for the diagnosis of AVWS. PMID:27841910

  13. Dynamics of Diffusion Flames in von Karman Swirling Flows Studied

    NASA Technical Reports Server (NTRS)

    Nayagam, Vedha; Williams, Forman A.

    2002-01-01

    Von Karman swirling flow is generated by the viscous pumping action of a solid disk spinning in a quiescent fluid media. When this spinning disk is ignited in an oxidizing environment, a flat diffusion flame is established adjacent to the disk, embedded in the boundary layer (see the preceding illustration). For this geometry, the conservation equations reduce to a system of ordinary differential equations, enabling researchers to carry out detailed theoretical models to study the effects of varying strain on the dynamics of diffusion flames. Experimentally, the spinning disk burner provides an ideal configuration to precisely control the strain rates over a wide range. Our original motivation at the NASA Glenn Research Center to study these flames arose from a need to understand the flammability characteristics of solid fuels in microgravity where slow, subbuoyant flows can exist, producing very small strain rates. In a recent work (ref. 1), we showed that the flammability boundaries are wider and the minimum oxygen index (below which flames cannot be sustained) is lower for the von Karman flow configuration in comparison to a stagnation-point flow. Adding a small forced convection to the swirling flow pushes the flame into regions of higher strain and, thereby, decreases the range of flammable strain rates. Experiments using downward facing, polymethylmethacrylate (PMMA) disks spinning in air revealed that, close to the extinction boundaries, the flat diffusion flame breaks up into rotating spiral flames (refs. 2 and 3). Remarkably, the dynamics of these spiral flame edges exhibit a number of similarities to spirals observed in biological systems, such as the electric pulses in cardiac muscles and the aggregation of slime-mold amoeba. The tail of the spiral rotates rigidly while the tip executes a compound, meandering motion sometimes observed in Belousov-Zhabotinskii reactions.

  14. John von Neumann and Klaus Fuchs: an Unlikely Collaboration

    NASA Astrophysics Data System (ADS)

    Bernstein, Jeremy

    2010-03-01

    I discuss the origin of the idea of making a fusion (hydrogen) bomb and the physics involved in it, and then turn to the design proposed for one by the unlikely collaborators John von Neumann and Klaus Fuchs in a patent application they filed at Los Alamos in May 1946, which Fuchs passed on to the Russians in March 1948, and which with substantial modifications was tested on the island of Eberiru on the Eniwetok atoll in the South Pacific on May 8, 1951. This test showed that the fusion of deuterium and tritium nuclei could be ignited, but that the ignition would not propagate because the heat produced was rapidly radiated away. Meanwhile, Stanislaw Ulam and C.J. Everett had shown that Edward Teller’s Classical Super could not work, and at the end of December 1950, Ulam had conceived the idea of super compression, using the energy of a fission bomb to compress the fusion fuel to such a high density that it would be opaque to the radiation produced. Once Teller understood this, he invented a greatly improved, new method of compression using radiation, which then became the heart of the Ulam-Teller bomb design, which was tested, also in the South Pacific, on November 1, 1952. The Russians have freely acknowledged that Fuchs gave them the fission bomb, but they have insisted that no one gave them the fusion bomb, which grew out of design involving a fission bomb surrounded by alternating layers of fusion and fission fuels, and which they tested on November 22, 1955. Part of the irony of this story is that neither the American nor the Russian hydrogen-bomb programs made any use of the brilliant design that von Neumann and Fuchs had conceived as early as 1946, which could have changed the entire course of development of both programs.

  15. Thom, Alexander (1894-1945)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    British engineer and archaeo-astronomer, born in Scotland, became professor of engineering science at Oxford University. Accurately surveyed the megalithic sites in Britain and the megalithic lunar observatories, identifying their shapes and astronomical alignments. He claimed to have discovered in the dimensions of the circles, as apparently used by the megalithic constructors, quanta of length ...

  16. Obituary: Alexander Dalgarno (1928 - 2015)

    NASA Astrophysics Data System (ADS)

    Hartquist, Tom; Babb, James F. Babb; Loeb, Avi

    Alex Dalgarno's major contributions to the understanding of fundamental atomic and molecular processes enabled him to develop diagnostics of the physical conditions of atmospheres and astrophysical sources and to elucidate the roles of such processes in controlling those environments. He greatly influenced the research of physicists, chemists, atmospheric scientists, and astronomers, leading Sir David Bates to write, "There is no greater figure than Alex in the history of atomic physics and its applications." Alex was born and grew up in London. As a child, he enjoyed mathematical puzzles and did well at sports. He was invited to try out for the Tottenham Hotspur soccer team, but his professional sporting career ended due to an injury, which did not prevent Alex playing tennis and squash into his ninth decade. In 1945 Alex began to study Mathematics at University College London (UCL). In 1947 Sir Harrie Massey invited him to work for a PhD in Physics and suggested that Alex investigate collisions of metastable helium atoms in helium gas to determine the cross sections for excitation transfer. Richard Buckingham was Alex's immediate supervisor. After completing his graduate study in 1951, Alex became a member of staff in Applied Mathematics at the Queen's University of Belfast (QUB). He served as the Director of the Computational Laboratory after a 1954 visit to MIT, which had an electronic computer, led Alex to persuade colleagues that QUB needed one. In 1957, the poet Philip Larkin was the best man at the marriage of Alex to Barbara Kane. They had four children, Fergus, Penelope, Piers, and Rebecca, but the marriage dissolved after ten years. Alex's important work during the 1950s on the quantitative evaluation of long-range interactions underpinned his collaborations on precise scattering calculations relevant to ultra-cold collisions and the formation of atomic Bose-Einstein condensates over four decades later. He investigated the theory of atomic and molecular collisions and calculated charge transfer cross sections. Some of these proved later to be important for forming the spectra of diffuse astronomical matter surrounding high mass stars and 100 million solar mass black holes at the centers of active galaxies. In the early 1950s David Bates stimulated Alex's interest in the study of quantum processes occurring in the upper terrestrial atmosphere. Together they considered the sources of the nightglow and dayglow features and concluded that the altitudes previously inferred for them from observations were up to several hundred kilometers too large. Experiments carried on V2 rockets, like those seen by Alex in wartime London, proved him and David to be right. Alex felt that though many theorists believe that "physics is embodied in its equations," it is instead "to be found in the solutions to the equations." He was a master at developing and applying methods that simplified calculations leading to reliable solutions. Exploiting the contemporary advances in electronic computation, by the 1960s Alex and his colleagues were able to address atomic and molecular processes of increasing complexity. Their development and early applications of the S-matrix theory of molecular rotational excitation by particle impact triggered major advances in molecular physics and theoretical chemistry and in the understanding of processes important in many environments, including a wide variety of astrophysical sources. In 1967 Alex became a professor in the Harvard Department of Astronomy and a member of the staff of the Smithsonian Astrophysical Observatory. He was a team member for several Atmosphere Explorer satellite missions, which elucidated the roles of atoms and ions in the upper atmosphere and paved the way for further applications to the other planets. By 1969 Alex was publishing papers on molecular hydrogen (H2) radiative processes, including photodissociation, in which the foundations of molecular astrophysics began to emerge. H2 is the most abundant astrophysical molecule and the main constituent of the regions where stars form. Interstellar H2 was first detected directly in the following year, and data for interstellar H2 began to become abundant in 1973. Alex was well prepared and led efforts to interpret these data, from which he was able to infer the physical properties of diffuse interstellar molecular clouds. At nearly the same time he was involved in work on the ionization and energy deposition in H2 by nearly relativistic and relativistic particles called cosmic rays. The work has relevance to emission in the atmospheres of the giant planets, as well as for conditions in interstellar molecular clouds. Cosmic ray induced ionization initiates much of the basic chemistry in star forming regions, and the emissions of the product molecules control the temperatures and allow the diagnosis of the physical conditions and dynamics of the stellar nurseries. For more than four decades Alex elucidated the chemical networks governing the molecular abundances in a wide variety of astrophysical sources including star forming regions, supernova ejecta, the pregalactic universe, and extreme environments like those in the vicinities of X-ray sources powered by accretion onto black holes. The refinement of the models led to calculations predicting the existence of subsequently discovered negative ions in giant molecular clouds. One of his astrophysical interests that intrigued him late in his career was the emission of soft X-rays by comets and in the heliosphere due to charge transfer with solar wind particles, and he also worked on related processes occurring in the atmospheres of the giant planets. Alex remained very active in fundamental atomic and molecular physics, as well as for its applications to astrophysics and to terrestrial and extraterrestrial planetary atmospheres. Ultra-cold collisions and ultra-cold chemistry were major interests for Alex for much of the latest phase of his career, most recently with pioneering work on atom-molecule collisions. In the early 1980s Alex had concerns about the future of atomic, molecular, and optical (AMO) physics in the United States, where it was inadequately funded and somewhat out of fashion in many of the physics departments providing most of the physicists who became university faculty. Alex played a key role in efforts to address this issue and led a proposal to the National Science Foundation that resulted in the founding on 1 November 1988 of the Institute of Theoretical Atomic and Molecular Physics (ITAMP) at the Harvard-Smithsonian Center for Astrophysics. Alex served for five years as the first ITAMP director. A number of the former ITAMP students and postdoctoral researchers have become leading AMO physicists, and its visitor program and workshops have led to the identification and stimulation of the leading areas of AMO physics. Alex was a Fellow of the Royal Society, a member of the National Academy of Sciences, and a member (Honorary) of the Royal Irish Academy. He received many medals, including the Benjamin Franklin Medal in Physics, the Royal Society's Hughes Medal, the Royal Astronomical Society's Gold Medal, the American Geophysical Society's Fleming Medal, and the Royal Society of Chemistry's Spiers Medal. He served as the editor of the Astrophysical Journal Letters for nearly thirty years starting in 1973, as the Chair of the Harvard Department of Astronomy from 1971 to 1976, and as the Acting Director of Harvard College Observatory and then the Acting Director of the Harvard-Smithsonian Center for Astrophysics from 1971 to 1973 during a critical period of its existence. Alex was a gifted mentor who spoke and wrote with pride of his former students and postdoctoral researchers. He was able to match projects very well with the abilities of the students. He made availability to students a special priority, and despite his supply of problems would encourage students as they developed their own. Alex was very supportive of junior scientists as they developed their careers, and in addition to writing many letters of recommendation he made many visits to colleagues as they were establishing themselves elsewhere. Furthermore, Alex very graciously hosted a number of his former students when they visited. He combined quiet modesty with a confidence that reassured others, and his humor was dry, interactive, and friendly. Alex passed away peacefully on 9 April 2015 in Cambridge, Massachusetts in the company of Fern Creelan, who was his partner for 30 years.

  17. Postpartum von Willebrand factor levels in women with and without von Willebrand disease and implications for prophylaxis.

    PubMed

    James, A H; Konkle, B A; Kouides, P; Ragni, M V; Thames, B; Gupta, S; Sood, S; Fletcher, S K; Philipp, C S

    2015-01-01

    The aim of this study was to elucidate the fall in von Willebrand factor (VWF) and factor VIII activity (FVIII) after childbirth in women with and without von Willebrand disease (VWD). VWF:RCo, VWF:Ag, and FVIII were obtained in the third trimester of pregnancy, on admission for childbirth, and 10 times postpartum. Specimens were processed within 4 h and analysed centrally. Means were calculated at each time point. Forty women (40 pregnancies) without VWD and 32 women (35 pregnancies) with VWD were enrolled. 15/32 with VWD were treated (30% of those with type 1 and all of those with type 2) in 17 pregnancies. Treatments prior to delivery consisted of desmopressin (2/17), VWF concentrate (15/17) and after delivery VWF concentrate (16/17). Duration of treatment was 0-21 days (median 6). VWF levels peaked at 250% of baseline--4 h postpartum in women with VWD and 12 h postpartum in women without VWD. Thereafter, VWF levels fell rapidly, approached baseline at 1 week and reached baseline at 3 weeks. Except immediately postpartum, when the levels among treated cases were higher, levels among women with VWD appeared to parallel, but were lower than those among women without VWD. Levels were lowest among those who received treatment. VWF levels fall rapidly after childbirth. Except immediately postpartum, current treatment strategies do not raise VWF levels to the levels of women without VWD or even to the levels of women with milder, untreated VWD. Consequently, women with VWD may be at risk of postpartum haemorrhage despite treatment.

  18. Diagnostic Differentiation of von Willebrand Disease Types 1 and 2 by von Willebrand Factor Multimer Analysis and DDAVP Challenge Test.

    PubMed

    Michiels, Jan Jacques; Smejkal, Petr; Penka, Miroslav; Batorova, Angelika; Pricangova, Tatiana; Budde, Ulrich; Vangenechten, Inge; Gadisseur, Alain

    2016-01-01

    The European Clinical Laboratory and Molecular (ECLM) classification of von Willebrand disease (vWD) is based on the splitting approach which uses sensitive and specific von Willebrand factor (vWF) assays with regard to the updated molecular data on structure and function of vWF gene and protein defects. A complete set of FVIII:C and vWF ristocetine cofactor, collagen binding, and antigen, vWF multimeric analysis in low- and medium-resolution gels, and responses to desmopressin (DDAVP) of FVIII:C and vWF parameters are mandatory. The ECLM classification distinguishes recessive types 1 and 3 vWD from recessive vWD 2C due to mutations in the D1 and D2 domains and vWD 2N due to mutations in the D'-FVIII-binding domain of vWF. The ECLM classification differentiates between mild vWD type 1 with variable penetrance of bleedings from symptomatic dominant type 1 vWD secretion defect and/or clearance defect with normal vWF multimers versus vWD 1M and 2M with normal or smeary vWF multimers in low- and medium-resolution gels. High-quality multimeric analysis of vWF in medium-resolution gels based on a DDAVP challenge test clearly delineates and distinguishes each of the dominant type 2 vWDs 1/2E, 2M, 2B, 2A, and 2D caused by vWF gene mutations in the D3 multimerization domain, loss or gain-of-function mutations in the glycoprotein Ib receptor A1 domain, gene mutations in the A2 proteolytic domain, and the C-terminal dimerization domain, respectively.

  19. Dr. Wernher Von Braun leads a tour of the S-IC checkout area.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Eberhard Rees, Charles Schultze, James Webb, Elmer Staats, Comptroller General of the United States, and Dr. Wernher Von Braun tour the S-IC checkout area in the Marshall Space Flight Center quality lab.

  20. Dr. von Braun with Gen. Ostrander, Dr. Rees, and Gen. Barclay

    NASA Technical Reports Server (NTRS)

    1959-01-01

    In this 1959 photo, taken at Cape Canaveral, Florida, Dr. von Braun (2nd from left) Director of the U.S. Army Ballistic Missile Agency's (ABMA) Development Operations Division, is shown conferring with Air Force Major General Donald R. Ostrander (left), on assignment at NASA as launch vehicle director; Dr. Eberhard Rees, deputy to Dr. von Braun, and Army Brigadier General John Barclay, commander of the ABMA.

  1. Markov property and strong additivity of von Neumann entropy for graded quantum systems

    SciTech Connect

    Moriya, Hajime

    2006-03-15

    The quantum Markov property is equivalent to the strong additivity of von Neumann entropy for graded quantum systems. The additivity of von Neumann entropy for bipartite graded systems implies the statistical independence of states. However, the structure of Markov states for graded systems is different from that for tensor-product systems which have trivial grading. For three-composed graded systems we have U(1)-gauge invariant Markov states whose restriction to the marginal pair of subsystems is nonseparable.

  2. von Neumann measurement-related matrices and the nullity condition for quantum correlation

    NASA Astrophysics Data System (ADS)

    Zhao, MingJing; Ma, Teng; Zhang, TingGui; Fei, Shao-Ming

    2016-12-01

    We study von Neumann measurement-related matrices, and the nullity condition of quantum correlation. We investigate the properties of these matrices that are related to a von Neumann measurement. It is shown that these ( m 2 - 1) × ( m 2 - 1) matrices are idempotent, and have rank m - 1. These properties give rise to necessary conditions for the nullity of quantum correlations in bipartite systems. Finally, as an example we discuss quantum correlation in Bell diagonal states.

  3. Fibroblast growth factor-10 signals development of von Brunn's nests in the exstrophic bladder.

    PubMed

    Eastman, Rocky; Leaf, Elizabeth M; Zhang, Dianzhong; True, Lawrence D; Sweet, Robert M; Seidel, Kristy; Siebert, Joseph R; Grady, Richard; Mitchell, Michael E; Bassuk, James A

    2010-11-01

    von Brunn's nests have long been recognized as precursors of benign lesions of the urinary bladder mucosa. We report here that von Brunn's nests are especially prevalent in the exstrophic bladder, a birth defect that predisposes the patient to formation of bladder cancer. Cells of von Brunn's nest were found to coalesce into a stratified, polarized epithelium which surrounds itself with a capsule-like structure rich in types I, III, and IV collagen. Histocytochemical analysis and keratin profiling demonstrated that nested cells exhibited a phenotype similar, but not identical, to that of urothelial cells of transitional epithelium. Immunostaining and in situ hybridization analysis of exstrophic tissue demonstrated that the FGF-10 receptor is synthesized and retained by cells of von Brunn's nest. In contrast, FGF-10 is synthesized and secreted by mesenchymal fibroblasts via a paracrine pathway that targets basal epithelial cells of von Brunn's nests. Small clusters of 10pRp cells, positive for both FGF-10 and its receptor, were observed both proximal to and inside blood vessels in the lamina propria. The collective evidence points to a mechanism where von Brunn's nests develop under the control of the FGF-10 signal transduction system and suggests that 10pRp cells may be the original source of nested cells.

  4. Molecular and cellular biology of von Willebrand factor.

    PubMed

    Denis, Cécile V

    2002-01-01

    von Willebrand factor (VWF) is a plasma protein that performs 2 main functions in hemostasis: it mediates platelet adhesion to the injured vessel wall, and it carries and protects coagulation factor VIII. VWF is synthesized through a multistep process in endothelial cells and megakaryocytes as a very large polymer composed of identical disulfide-linked 250-kd subunits. In endothelial cells, VWF not only directs the formation of its own storage granules, the Weibel-Palade bodies, but it also acts as a chaperone molecule to direct other proteins, such as P-selectin, into these granules. Upon stimulation of the endothelium, the Weibel-Palade bodies will be translocated to the plasma membrane, and their contents will be secreted into the plasma milieu. The expression of VWF can be regulated at different levels by a number of genetic and environmental factors, resulting in control of its activity. New roles for VWF, especially in inflammatory processes, have recently been suggested, indicating that some aspects of this well-studied protein remain to be investigated.

  5. Characterization of the mouse von Willebrand factor promoter.

    PubMed

    Guan, J; Guillot, P V; Aird, W C

    1999-11-15

    Expression of the von Willebrand factor (vWF) gene is restricted to the endothelial and megakaryocyte lineages. Within the endothelium, expression of vWF varies between different vascular beds. We have previously shown that the human vWF promoter spanning a region between -2182 (relative to the start site of transcription) and the end of the first intron contains information for environmentally responsive, vascular bed-specific expression in the heart, skeletal muscle, and brain. In the present study, we cloned the mouse vWF (mvWF) promoter and studied its function in cultured endothelial cells and transgenic mice. In transient transfection assays, the mvWF gene was found to be regulated by distinct mechanisms in different endothelial cell subtypes. In independent lines of transgenic mice, an mvWF promoter fragment containing DNA sequences between -2645 and the end of the first intron directed endothelial cell-specific expression in the microvascular beds of the heart, brain, and skeletal muscle as well as the endothelial lining of the aorta. In 1 line of mice, reporter gene activity was also detected in bone marrow megakaryocytes. Taken together, these findings suggest that both the mouse and human vWF promoters are regulated by vascular bed-specific mechanisms.

  6. Functional property of von Willebrand factor under flowing blood.

    PubMed

    Sugimoto, Mitsuhiko; Miyata, Shigeki

    2002-01-01

    von Willebrand factor (vWF) is produced in megakaryocytes and endothelial cells, is stored in the alpha-granule of platelets and in the Weibel-Palade body of endothelial cells, and is present in plasma and vascular subendothelium. This huge protein with a unique multimeric structure plays a pivotal role in both hemostasis and pathological intravascular thrombosis, in which vWF contributes to both platelet adhesion/aggregation and blood coagulation through its multiple adhesive functions for the platelet membrane receptors, glycoprotein Ib-IX-V complex, integrin alphaIIbbeta3, heparin, various types of collagen, and coagulation factor VIII. Among various functions, the most characteristic feature of vWF is its determinant role on platelet thrombus formation under high-shear-rate conditions. Indeed, at in vivo rheological situations where platelets are flowing with high speed in the bloodstream, the only reaction that can initiate mural thrombogenesis is the interaction of vWF with platelet glycoprotein Ibalpha. The recent x-ray analysis of the crystal structure of various functional domains and functional studies of this protein under experimental flow conditions have rapidly advanced and revised our knowledge of the structure-function relationships of vWF, a key protein for hemostasis and arterial thrombosis.

  7. Ludwig von Bertalanffy's Organismic View on the Theory of Evolution

    PubMed Central

    Drack, Manfred

    2015-01-01

    Ludwig von Bertalanffy was a key figure in the advancement of theoretical biology. His early considerations already led him to recognize the necessity of considering the organism as a system, as an organization of parts and processes. He termed the resulting research program organismic biology, which he extended to all basic questions of biology and almost all areas of biology, hence also to the theory of evolution. This article begins by outlining the rather unknown (because often written in German) research of Bertalanffy in the field of theoretical biology. The basics of the organismic approach are then described. This is followed by Bertalanffy's considerations on the theory of evolution, in which he used methods from theoretical biology and then introduced his own, organismic, view on evolution, leading to the demand for finding laws of evolution. Finally, his view on the concept of homology is presented. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 77–90, 2015. © 2015 The Authors. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution published by Wiley Periodicals, Inc. PMID:25727202

  8. THE FINE STRUCTURE OF VON EBNER'S GLAND OF THE RAT

    PubMed Central

    Hand, Arthur R.

    1970-01-01

    The fine structure of von Ebner's gland was studied in untreated rats and rats stimulated to secrete by fasting-refeeding or injection of pilocarpine. Cytological features were similar to those reported for pancreas and parotid gland. Abundant granular endoplasmic reticulum filled the basal portion of the cell, a well-developed Golgi complex was located in the vicinity of the nucleus, and the apical portion of the cell was filled with dense secretory granules. Dense heterogeneous bodies resembling lysosomes were closely associated with the Golgi complex. Coated vesicles were seen in the Golgi region and also in continuity with the cell membrane. Granule discharge occurred by fusion of the granule membrane with the cell membrane at the secretory surface. Successive fusion of adjacent granules to the previously fused granule formed a connected string of granules in the apical cytoplasm. Myoepithelial cells were present within the basement membrane, and nerve processes were seen adjacent to acinar and myoepithelial cells. Duct cells resembled the intercalated duct cells of the major salivary glands. PMID:5411078

  9. [Hermann von Helmholtz and Carl Stumpf on consonance and dissonance].

    PubMed

    Kursell, Julia

    2008-06-01

    The article juxtaposes Hermann von Helmholtz's work in the experimental physiology of hearing and Carl Stumpf's tone psychology, focusing on the problem of consonance and dissonance in music. It argues that the experimental set-up plays a major role in the approaches to hearing of both Helmholtz and Stumpf, shaping their redefinition of the musical concepts of consonance and dissonance. Helmholtz, however, explains dissonance as resulting from the beats that are heard when sound waves interfere, while Stumpf explains consonance from the fusion (Verschmelzung) of sounds, noting that two tones, depending on their distance cannot always be recognized as two but are heard as one single tone. Helmholtz's definition of dissonance eventually threatens his own theory of hearing, which is based on the mechanical principle of resonance and considers sound to be composed of sinusoidal waves. Both the physical and the mathematical tools he uses cannot easily be brought into accordance with his experimental findings on beats, which ask for a discrimination of fast changes in intensity. Dissonance thus becomes "unrecomendable" for Helmholtz, because it overstrains the ear. Stumpf's research, in contrast, has its point of departure in the historically given set of intervals and tries to find a principle that would explain this choice. His tests with experimental subjects who have no conscious knowledge of musical harmony and prove incapable to follow or reproduce music reveals to him a difference between the unity and multiplicity of tones.

  10. [Hans von Hattingberg between psychoanalysis and National Socialism].

    PubMed

    Keifenheim, Katharina Eva

    2011-01-01

    Hans von Hattingberg (1879-1944) worked as a neurologist and psychoanalyst in Munich and Berlin from about 1910 to 1944. He was a prolific writer, but met with increasing disapproval from Freud and his circle. An advocate of the union of different psychotherapeutic schools, he was initially a marginal figure in the professional field. With Hitler's rise to power his career prospered: He was offered the position of a lecturer for psychotherapy and became head of the research department at the "Göring Institute". He came to prominence with his writings on the "Neue deutsche Seelenheilkunde" despite the fact that this was never his preferred topic. The main themes of his publications were marriage, love and female emancipation. Those works contain only little of the standard Nazi ideology of the time. Not only was Hattingberg never a member of the NSDAP (the ruling party), but in some respects he could conceivably be considered a member of the resistance. The article outlines the most important stages of Hattingberg's life and focuses on the question of how he positioned himself after 1933, when it became vital for him to reconcile psychoanalysis and National Socialism.

  11. Emperor Ashoka: Did he suffer from von Recklinghausen's diseases?

    PubMed Central

    Wig, N. N.; Sharma, Sheetal

    2015-01-01

    Emperor Ashoka is widely regarded as one of the greatest rulers of India. This paper mainly deals with his medical condition as recorded in the Buddhist texts of Sri Lanka as well as in the Buddhist texts of North India and Nepal. These sources mention his skin disorder which is described as very rough and unpleasant to touch. He is also known to have episodes of loss of consciousness at various times in his life. One of the earliest representations of Ashoka, about 100 years after his death at one of the gates of Sanchi Stupa, shows Ashoka fainting when visiting the Bodhi tree and being held by his queens. In this sculpture, Emperor Ashoka is shown as a man of short height, large head and a paunchy abdomen. In this paper, it is speculated that Emperor Ashoka was probably suffering from von Recklinghausen disease (Neurofibromatosis Type 1), which could explain his skin condition, episodes of loss of consciousness (probably epilepsy) and other bodily deformities. PMID:25657467

  12. Von recklinghausen disease: one patient – various problems

    PubMed Central

    Miziołek, B; Brzezińska-Wcisło, L

    2016-01-01

    Abstract von Recklinghausen disease (vRD), more widely known as neurofibromatosis type 1, belongs to a group of genetic disorders and it is considered to be the most common genodermatosis. The disease has an autosomal dominant pattern of inheritance that involves mutations within the NF1 gene located on chromosome 17 in locus q11.2. The product of the NF1 gene is neurofibromin and the protein is well known to be a tumor suppressor factor. This counteracts possible overactivity of RAS (protein)/MAPK (mitogen-activated protein kinase) and RAS/PI3K/AKT/mTOR (phoshatydyloinositol-3-kinase/V-akt murine thy-moma viral oncogene homologue/mammalian target of rapamycin) signaling transduction pathways, preventing from uncontrolled cell proliferation and subsequent tumor formation. A loss of proper functioning of this protein leads to a development of vRD; however, a large variability in a phenotype of the disease and the onset of cutaneous findings, not necessarily in childhood, may provide a clinical diagnosis of the disease late in adulthood. We present a 52-year-old male in whom the diagnosis of vRD was proposed in the sixth decade of life, despite of multiple nodular lesions disseminated over the skin of the whole body and different neurological disturbances, not considered for a long time as manifestations of genodermatosis. PMID:27785414

  13. Magnetohydrodynamics measurements in the von Karman sodium experiment

    NASA Astrophysics Data System (ADS)

    Bourgoin, Mickael; Marie, Louis; Petrelis, Francois; Gasquet, Cecile; Guigon, Alain; Luciani, Jean-Baptiste; Moulin, Marc; Namer, Frederic; Burguete, Javier; Chiffaudel, Arnaud; Fauve, Stephan; Odier, Philippe

    2002-09-01

    We study the magnetic induction in a confined swirling flow of liquid sodium, at integral magnetic Reynolds numbers up to 50. More precisely, we measure in situ the magnetic field induced by the flow motion in the presence of a weak external field. Because of the very small value of the magnetic Prandtl number of all liquid metals, flows with even modest Rm are strongly turbulent. Large mean induction effects are observed over a fluctuating background. As expected from the von Karman flow geometry, the induction is strongly anisotropic. The main contributions are the generation of an azimuthal induced field when the applied field is in the axial direction (an Omega effect) and the generation of axial induced field when the applied field is the transverse direction (as in a large scale alpha effect). Strong fluctuations of the induced field, due to the flow nonstationarity, occur over time scales slower than the flow forcing frequency. In the spectral domain, they display a f-1 spectral slope. At smaller scales (and larger frequencies) the turbulent fluctuations are in agreement with a Kolmogorov modeling of passive vector dynamics.

  14. Modellbasierte Segmentierung von differenzierten Lymphknoten in CT-Daten

    NASA Astrophysics Data System (ADS)

    Dornheim, Lars; Dornheim, Jana

    Für die computerbasierte Diagnoseunterstützung bei Tumorerkrankungen ist Wissen über Lage, Ausdehnung und Art der Lymphknoten für die TNM-Klassifikation nötig. Für die computergestütze Planung nachfolgender Eingriffe wie der Hals-Lymphknoten-Ausräumung, ist dieses Wissen ebenfalls von Bedeutung. Deshalb ist ein effizientes und exaktes Segmentierungsverfahren für Lymphknoten in CT-Datensätzen erforderlich, das besonders auch mit pathologisch veränderten Lymphknoten zurechtkommt. Basierend auf früheren Arbeiten präsentieren wir in dieser Arbeit ein deutlich weiterentwickeltes, modellbasiertes Segmentierungsverfahren für Lymphknoten in CT-Datensätzen, mit dem nun besonders auch vergrößerte sowie nekrotische Lymphknoten adressiert werden. Unser Verfahren wurde an 21 Lymphknoten aus 5 CT-Datensätzen getestet, darunter mehrere vergrößerte und nekrotische. Die Ergebnisse liegen im Bereich der Inter-Personen-Varianz und verbessern die Ergebnisse früherer Arbeiten noch einmal spürbar.

  15. Bifurcation analysis of an infinite array of von Karman Streets

    NASA Astrophysics Data System (ADS)

    Ghaemi Oskouei, Babak; Kanso, Eva; Newton, Paul K.

    2008-11-01

    This research investigates the behavior of an infinite array of (inverse) von Karman streets. Primary motivation is to model the wake dynamics in large fish schools. Ignoring the fish we focus on the dynamic interaction of multiple wakes. In particular, we investigate the problem of fluid transport between adjacent vortex streets for its relevance to understanding the transport of oxygen and nutrients to inner fish in large schools as well as understanding flow barriers to passive locomotion. We prove that the configuration of vortices is in relative equilibrium, meaning that the streamline pattern remains steady in the frame moving with vortices. We look at the topology of these streamline patterns plotted in the moving frame which lends insight to fluid transport through the mid-wake region. Fluid is advected along different paths depending on the distance separating two adjacent streets. When the streets are far apart, the dynamics is decoupled and fluid is transported globally between two adjacent streets. When the streets get closer to each other, the number of streets that enter into partnership in transporting fluid among themselves increases. This observation motivates a bifurcation analysis which links the distance between streets to the maximum number of streets transporting fluid among themselves.

  16. Darwin the geologist: Between Lyell and von Buch.

    PubMed

    Gohau, Gabriel

    2010-02-01

    Upon returning from his voyage on the Beagle, Darwin prepared reports of his geological observations. Together, these reveal Darwin's approach to reasoning about geology. Darwin argued that successive terraces prove a very gradual elevation of the coast that lagoon islands show a reciprocal sinking of the oceanic floor. Hence, Darwin reinforced Lyell's uniformitarian, or steady state theory. Unlike lagoon islands, the movement of erratic boulders onto the plains is evidence of forces, which do not now exist. Darwin and Lyell attributed this movement to floating icebergs. However, mountain formation remained difficult for them to explain with reference to contemporary causes. Lyell discovered uplifts in Scandinavia, which resulted from epirogenesis, whereas mountain formation is an orogenesis, which involves both folding and uplift. Darwin was more impressed by uplift than by folds. However, when in Cordillera he saw strata overturned by masses of injected rock, proving successive periods of violence, Darwin took a position, which was closer to the plutonic theories of von Buch and Humboldt than it was to Lyell's uniformitarian views.

  17. [Heinrich von Kleist--crisis and creative overcoming].

    PubMed

    Schlimme, J

    2001-07-01

    Heinrich von Kleist's life was shaken repeatedly by negative life-events, finally he committed suicide in his last life-crisis (1811). His work was mostly understood as descriptions of negative life-events and failed-being. In this article it will be shown that in at least two "crises" Kleist's work can be understood as a creative overcome of those. Kleist shows in his "Essay to Find a Sure Way to Happiness" (1799) his way of solving his "Soldier-Crisis" (1798), a depressive episode. In "The Broken Jug" (1802 - 1805) he shows the implications of a philosophical problem experienced in his "Kant-Crisis" (1801) and offers chances to overcome this particular crisis, which still seems to be an actual problem of ourselves. Though his crises must be understood as depressive episodes, at least the "Kant-Crisis" with its connections to philosophical and artistical matters seems to be more complicated than a simple depressive syndrome. Kleist formulates his basic life-experience, to be repeatedly shaken by "crises" respectively depressive episodes and the necessity to overcome each in a new way of living.

  18. [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.

  19. Keeping von Willebrand Factor under Control: Alternatives for ADAMTS13.

    PubMed

    Tersteeg, Claudia; Fijnheer, Rob; Pasterkamp, Gerard; de Groot, Philip G; Vanhoorelbeke, Karen; de Maat, Steven; Maas, Coen

    2016-02-01

    Von Willebrand factor (VWF) is one of the most important proteins of the hemostatic system. Its multimeric state is essential for its natural function to guide platelets to sites of injury. ADAMTS13 is the key protease that regulates the multimeric state of VWF. Without ADAMTS13, VWF multimers can grow to pathologically large sizes. This is a risk factor for the life-threatening condition thrombotic thrombocytopenic purpura (TTP). In this condition, VWF-rich thrombi occlude the microvasculature of various tissues. Intriguingly, a complete ADAMTS13 deficiency does not cause continuous TTP, either in patients or genetically targeted mice. Instead, TTP occurs in episodes of disease, separated by extended periods of remission. This indicates that regulating factors beyond ADAMTS13 are likely involved in this pathologic cascade of events. This raises the question of what really happens when ADAMTS13 is (temporarily) unavailable. In this review, we explore the possible role of complementary mechanisms that are capable of modifying the thrombogenic potential of VWF.

  20. Allosteric activation of ADAMTS13 by von Willebrand factor.

    PubMed

    Muia, Joshua; Zhu, Jian; Gupta, Garima; Haberichter, Sandra L; Friedman, Kenneth D; Feys, Hendrik B; Deforche, Louis; Vanhoorelbeke, Karen; Westfield, Lisa A; Roth, Robyn; Tolia, Niraj Harish; Heuser, John E; Sadler, J Evan

    2014-12-30

    The metalloprotease ADAMTS13 cleaves von Willebrand factor (VWF) within endovascular platelet aggregates, and ADAMTS13 deficiency causes fatal microvascular thrombosis. The proximal metalloprotease (M), disintegrin-like (D), thrombospondin-1 (T), Cys-rich (C), and spacer (S) domains of ADAMTS13 recognize a cryptic site in VWF that is exposed by tensile force. Another seven T and two complement C1r/C1s, sea urchin epidermal growth factor, and bone morphogenetic protein (CUB) domains of uncertain function are C-terminal to the MDTCS domains. We find that the distal T8-CUB2 domains markedly inhibit substrate cleavage, and binding of VWF or monoclonal antibodies to distal ADAMTS13 domains relieves this autoinhibition. Small angle X-ray scattering data indicate that distal T-CUB domains interact with proximal MDTCS domains. Thus, ADAMTS13 is regulated by substrate-induced allosteric activation, which may optimize VWF cleavage under fluid shear stress in vivo. Distal domains of other ADAMTS proteases may have similar allosteric properties.

  1. Von Hippel-Lindau disease involving pancreas and biliary system

    PubMed Central

    Zhi, Xu-Ting; Bo, Qi-Yu; Zhao, Feng; Sun, Dong; Li, Tao

    2017-01-01

    Abstract Rationale: Von Hippel-Lindau (VHL) disease is a rare inherited, autosomal-dominant syndrome caused by heterozygous germline mutations in the VHL gene. VHL patients are prone to develop benign and malignant tumors and cysts in multiple organ systems involving kidneys, pancreas and central nervous system (CNS). The varied and complex clinical manifestations and radiological findings of VHL are of interest. Patient concerns: We report a 38-year-old woman with a ten-year history of VHL disease involving both pancreas and biliary system. To the best of our knowledge, direct involvement of the biliary system in VHL disease has never been reported. Diagnoses: The diagnosis was established via computed tomography scan and was confirmed by genetic testing. Interventions: The patient chose to receive conservative treatment and was followed up by magnetic resonance cholangiopancreatography and magnetic resonance imaging examination. Outcomes: Renal angiomas and cysts were found during follow-up and there were no evidence of malignant change of the pancreas and biliary system. Lessons: We described the first case of VHL-associated choledochal cysts and may present new visceral manifestations of VHL disease. Gastroenterologists should be aware of the clinical presentations of this rare disease for early detection of its life-threatening manifestations. PMID:28072736

  2. Multimeric analysis of von Willebrand factor in megakaryocytes.

    PubMed

    Kupinski, J M; Miller, J L

    1985-06-15

    Von Willebrand factor (vWF) is a glycoprotein that appears to play a major role in subserving the adhesion of platelets to subendothelium during hemostasis. Endothelial cells have been shown capable of synthesizing and releasing this large, multimeric glycoprotein that normally circulates in the plasma in association with the factor VIII coagulant molecule. Megakaryocytes, the precursor cells of blood platelets, also appear to possess vWF biosynthetic capacity, since cultured guinea pig megakaryocytes have been shown to produce a polypeptide precipitable by antibody to vWF. We now report a study of the multimeric structure of vWF in the megakaryocyte, as well as a quantitative comparison of megakaryocyte vWF with that of platelets and plasma in the guinea pig. Multimeric analysis on SDS agarose gels employing 125I-emu anti-human vWF revealed striking homology between human and guinea pig vWF. Platelets and megakaryocytes from the same guinea pigs contained vWF of highly comparable multimeric composition. Moreover, megakaryocytes and platelets both contained a subset of very high molecular weight multimers not present in plasma. Quantitation of vWF in megakaryocytes and platelets was achieved with a radioimmunoassay performed on detergent (NP-40) lysates of washed cells. These measurements showed that megakaryocytes and platelets contain 0.079 and 0.069 U of vWF per mg protein, respectively. The results of these studies suggest that megakaryocytes represent the primary, if in fact not sole, source of platelet vWF.

  3. Philipp Frank, Richard von Mises, and the Frank-Mises

    NASA Astrophysics Data System (ADS)

    Siegmund-Schultze, Reinhard

    2007-01-01

    The theoretical physicist Philipp Frank (1884 1966) and the applied mathematician Richard von Mises (1883 1953) both received their university education in Vienna shortly after 1900 and became friends at the latest during the Great War.They were attached to the Vienna Circle of Logical Positivists and wrote an influential two-part work on the differential and integral equations of mechanics and physics, the Frank-Mises, of 1925 and 1927, with its second edition following in 1930 and 1935.This work originated in the lectures that the mathematician Bernhard Riemann (1826 1866) delivered on partial differential equations and their applications to physical questions at the University of Göttingen between 1854 and 1862, which were edited and published posthumously in1869 by the physicist Karl Hattendorff (1834 1882).The immediate precursor of the Frank-Mises, however, was the extensive revision of Hattendorff’s edition of Riemann’s lectures that the mathematician Heinrich Weber (1842 1913) published in two volumes, the Riemann-Weber, of 1900 and 1901, with its second edition following in 1910 and 1912. I trace this historical lineage, explore the nature and contents of the Frank-Mises, and discuss its complementary relationship to the first volume of the text that the mathematicians Richard Courant (1888 1972) and David Hilbert (1862 1943) published on the methods of mathematical physics in 1924, the Courant-Hilbert,which, when it and its second volume of 1937 were translated into English and extensively revised in 1953 and 1961, eclipsed the classic Frank-Mises.

  4. von Willebrand factor storage requires intact prosequence cleavage site.

    PubMed

    Journet, A M; Saffaripour, S; Cramer, E M; Tenza, D; Wagner, D D

    1993-02-01

    Large multimers of the adhesive glycoprotein von Willebrand factor (vWf) are stored in endothelial cells in rod-shaped granules called Weibel-Palade bodies, while small multimers are secreted constitutively. Expression of pro-vWf in other cells with a regulated pathway of secretion, results in formation of vWf-containing storage granules that have a morphology similar to Weibel-Palade bodies. vWf expressed without its prosequence is not stored. To evaluate the importance of prosequence cleavage in vWf storage, the Arg at position -1, known to be necessary for cleavage, was mutated to Gly. Transfection of this cleavage mutant into two cell lines with a regulated pathway of secretion (RIN 5F and AtT-20 cells) led to the formation of large multimers. However, treatment of the cell lysates by the enzyme endoglycosidase H (Endo-H) did not reveal significant amounts of intracellular Endo-H-resistant vWf, which indicates the absence of a pool of stored processed vWf. In addition, no Weibel-Palade body-like structure was detected in these cells by immunofluorescence labeling with anti-vWf antiserum. Electron microscopy and immunocytochemistry of RIN 5F cells expressing the pro-vWf mutant confirmed the absence of Weibel-Palade body-like structures. In addition, anti-vWf-linked gold particles were found in the ER, occasionally in rounded granules and particularly in lysosomal structures which were abundant. We conclude that the formation of large aggregates is not sufficient to induce efficient vWf storage, and that the lack of cleavage of the prosequence may direct the mutant pro-vWf molecule to a degradative pathway. Therefore, the prosequence cleavage is a requirement for vWf storage.

  5. Evaluation of von Willebrand factor in COPD patients*

    PubMed Central

    Bártholo, Thiago Prudente; da Costa, Cláudia Henrique; Rufino, Rogério

    2014-01-01

    OBJECTIVE: To compare the absolute serum von Willebrand factor (vWF) levels and relative serum vWF activity in patients with clinically stable COPD, smokers without airway obstruction, and healthy never-smokers. METHODS: The study included 57 subjects, in three groups: COPD (n = 36); smoker (n = 12); and control (n = 9). During the selection phase, all participants underwent chest X-rays, spirometry, and blood testing. Absolute serum vWF levels and relative serum vWF activity were obtained by turbidimetry and ELISA, respectively. The modified Medical Research Council scale (cut-off score = 2) was used in order to classify COPD patients as symptomatic or mildly symptomatic/asymptomatic. RESULTS: Absolute vWF levels were significantly lower in the control group than in the smoker and COPD groups: 989 ± 436 pg/mL vs. 2,220 ± 746 pg/mL (p < 0.001) and 1,865 ± 592 pg/mL (p < 0.01). Relative serum vWF activity was significantly higher in the COPD group than in the smoker group (136.7 ± 46.0% vs. 92.8 ± 34.0%; p < 0.05), as well as being significantly higher in the symptomatic COPD subgroup than in the mildly symptomatic/asymptomatic COPD subgroup (154 ± 48% vs. 119 ± 8%; p < 0.05). In all three groups, there was a negative correlation between FEV1 (% of predicted) and relative serum vWF activity (r2 = −0.13; p = 0.009). CONCLUSIONS: Our results suggest that increases in vWF levels and activity contribute to the persistence of systemic inflammation, as well as increasing cardiovascular risk, in COPD patients. PMID:25210959

  6. Effect of von Willebrand factor on clot structure and lysis.

    PubMed

    Marchi, Rita; Rojas, Héctor

    2015-07-01

    Von Willebrand Factor (vWF) is constitutively secreted by the endothelium and incorporated in the fibrin clots under slow clotting conditions. The aim of the present work was to study the effect of vWF on clot structure and lysis. Purified fibrinogen was mixed with vWF or Tris-buffered saline and clotted with thrombin - activated factor XIII. Fibrin polymerization was followed by turbidity at 350 nm during 2.5 h. After this time, plasmin was added on the top of the clots, and the optical density (OD) was read until baseline values. vWF effect on network[Combining Acute Accent]s porosity was evaluated by permeation using the same clotting conditions as for fibrin polymerization. Clot structure was visualized and analyzed by laser scanning confocal microscopy (LSCM). The rate of fibrin polymerization was 1.47 mOD/s in the presence of vWF and 0.5 mOD/s when vWF was not added (P < 0.05). The fibrin lysis rate was approximately four times faster when vWF was added to fibrinogen. The fibrin network porosity was (20.4 ± 1.6) × 10 cm with vWF and (8.3 ± 1.2) × 10 cm without external vWF (P < 0.05). The analysis of LSCM images showed that vWF increased fibrin fibers diameter and the networks[Combining Acute Accent] pores size. In conclusion, vWF covalently crosslinked to fibrin modify its structure (increases fibrin diameter and the pores filling space of the meshwork) that accelerates the fibrin lysis rate.

  7. A historical perspective: Bernhard von Langenbeck German surgeon (1810-1887).

    PubMed

    Cesmebasi, Alper; Oelhafen, Kim; Shayota, Brian J; Klaassen, Zachary; Tubbs, R Shane; Loukas, Marios

    2014-10-01

    Bernhard von Langenbeck is undeniably one of the world's greatest surgeons and inventors. The influence which he exerted upon the practice of surgery, as apparent by the numerous surgical tools and 21 operations credited to his name, represents the notable contributions of this amazing man. Despite the tools and techniques which bear his name, the establishment of a surgical journal, and his role in co-founding the German Surgical Society, many attest that Bernhard von Langenbeck's greatest contribution to the professional field was the vast knowledge he imparted on his pupils. Commonly credited with training nearly every celebrated surgical operator of his time, von Langenbeck merits posthumous acknowledgement for his vast contributions to the field of medicine and surgery.

  8. P-selectin and von Willebrand factor in bovine mesenteric lymphatics: an immunofluorescent study.

    PubMed

    Di Nucci, A; Marchetti, C; Serafini, S; Piovella, F

    1996-03-01

    P-selectin (PADGEM, GMP-140, CD62) is an integral membrane protein specific to alpha granules of platelets and Weibel-Palade bodies of blood vascular endothelial cells. The presence in lymphatic endothelial cells of numerous Weibel-Palade bodies and their positivity to immunocytochemical reaction for von Willebrand factor have previously been characterized and described. Because von Willebrand factor and P-selectin codistribute in Weibel-Palade bodies of blood vascular endothelial cells we investigated the presence of both P-selectin and von Willebrand factor in lymphatic endothelium. Lymphatic vessels expressed positive reaction to immunocytochemical assay thereby demonstrating the presence of P-selectin in the endothelium. Distribution and intensity of the reaction were similar to those observed in bovine blood vascular endothelium.

  9. An Alternative to Von Glasersfeld's Subjectivism in Science Education: Deweyan Social Constructivism

    NASA Astrophysics Data System (ADS)

    Garrison, Jim

    An influential view of constructivism in science and mathematics educational research and practice is that of Ernst von Glasersfeld. It is a peculiarly subjectivist form of constructivism that should not be attractive to science and mathematics educators concerned with retaining some sort of realism that leaves room for objectivity. The subjectivist constructivism of von Glasersfeld also becomes entangled in untenable mind/body and subject/object dualisms. Finally, these dualisms are unnecessary for social constructivism. I will provide one example of a social constructivist alternative to social constructivism, that of the pragmatic philosopher John Dewey. In presenting Dewey's position I will appeal to Ockham's razor, that is, the admonition not to multiply entities beyond necessity, to shave off the needless mentalistic and psychic entities that lead von Glasersfeld into his subjectivism and dualism.

  10. Interaction of Platelet Membrane Receptors with von Willebrand Factor, Ristocetin, and the Fc Region of Immunoglobulin G

    PubMed Central

    Moore, Anne; Ross, Gordon D.; Nachman, Ralph L.

    1978-01-01

    The agglutination of human platelets by ristocetin and von Willebrand factor was inhibited by aggregated immunoglobulin (Ig)G and by Fc fragments of IgG, but not by Fab, F(ab′)2 or pFc fragments of IgG. Because this inhibition occurred with formalin-fixed platelets as well as with normal platelets, a generalized aggregation of fluid membrane components by Fc fragments was not responsible for this inhibition of ristocetin and von Willebrand factor-induced agglutination. Reciprocal inhibition of platelet Fc receptors was produced by prior incubation of platelets with von Willebrand factor and ristocetin. Sucrose density gradient ultracentrifugation studies demonstrated that aggregated IgG did not form fluid-phase complexes with von Willebrand factor and ristocetin. Furthermore, passage of von Willebrand factor and ristocetin through a column of immobilized heat-aggregated IgG did not alter platelet agglutinating activity which indicates that aggregated IgG did not inactivate von Willebrand factor or ristocetin. Thus, it was likely that the IgG-mediated interference with platelet agglutination by ristocetin and von Willebrand factor did not occur in the fluid phase but at the platelet surface. These studies suggest that the platelet membrane Fc receptor may be either a part of, or sterically related to, the membrane glycoprotein I complex that interacts with von Willebrand factor, and that occupation of one of these surface components blocks the availability of the other. PMID:309473

  11. "'And They Lived Happily Ever After": The Fairy Tale of Radical Constructivism and Von Glasersfeld's Ethical Disengagement

    ERIC Educational Resources Information Center

    d'Agnese, Vasco

    2015-01-01

    Is von Glasersfeld's constructivism actually radical? In this article, I respond to this question by analyzing von Glasersfeld's main works. I argue that the essential theoretical move of radical constructivism--namely the assertion that reality is the construction of a human mind that only responds to the subjective perception of "what…

  12. Die Tabellen von Ulugh Beg. Die Sternkataloge des Ptolemäus, Ulugh Beg und Tycho Brahe im Vergleich

    NASA Astrophysics Data System (ADS)

    Schwan, Heiner

    2002-09-01

    Im 15. Jahrhundert schuf Ulugh Beg, der Herrscher von Samarkand (1394 - 1449), ein wichtiges Tabellenwerk. Das Kernstück dieses Werks (Zij Ulugh Beg, "Tabellen Ulugh Begs") ist ein Katalog mit 1018 Sternen, ihren Helligkeiten und Positionen. In diesem Bericht werden die Zij Ulugh Beg mit den großen Katalogen von Ptolemäus und Tycho Brahe verglichen.

  13. 78 FR 34090 - Lois Von Morganroth; Shiloh Warm Springs Ranch, LLC; Notice of Application for Transfer of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Lois Von Morganroth; Shiloh Warm Springs Ranch, LLC; Notice of Application for Transfer of License, and Soliciting Comments and Motions To Intervene On April 29, 2013, Lois Von Morganroth (transferor) and Shiloh...

  14. An Integrated Approach to von Willebrand Disease and Surgical Myocardial Revascularization

    PubMed Central

    Jiritano, Federica; Cristodoro, Lucia; Bevacqua, Egidio; Malta, Emanuele; Mastroroberto, Pasquale

    2015-01-01

    Cardiac surgery in patients with preexisting bleeding disorders can be a challenge. Cardiopulmonary bypass can lead to bleeding disorders, above all in patients with coagulopathy. We report the case of a 42-year-old woman, with type I von Willebrand disease, who underwent off-pump coronary artery bypass grafting. Beating heart surgery associated with an adequate replacement of von Willebrand factor and factor VIII levels were chosen to prevent bleeding disorders. Her postoperative course was uneventful and she was discharged home after 5 postoperative days. PMID:26693126

  15. Spontaneous haemothorax associated with von Recklinghausen's disease: review of occurrence in Japan

    PubMed Central

    Miura, H.; Taira, O.; Uchida, O.; Usuda, J.; Hirai, S.; Kato, H.

    1997-01-01

    The case history is presented of a 61 year old man with von Recklinghausen's disease who developed a spontaneous haemothorax. In spite of being asymptomatic for five days after drainage, he died as a result of fatal sudden re-bleeding. The post mortem examination showed dissection and rupture of the left subclavian artery. Microscopically, disarrangement of smooth muscle and decrease of elastic fibre was observed in the ruptured artery. Haemothorax in patients with von Recklinghausen's disease may require thoracotomy, even if the condition of the patient appears to be stable. 


 PMID:9227730

  16. (Never) Mind your p's and q's: Von Neumann versus Jordan on the foundations of quantum theory

    NASA Astrophysics Data System (ADS)

    Duncan, A.; Janssen, M.

    2013-03-01

    In 1927, in two papers entitled "On a new foundation [Neue Begründung] of quantum mechanics," Pascual Jordan presented his version of what came to be known as the Dirac-Jordan statistical transformation theory. Jordan and Paul Dirac arrived at essentially the same theory independently of one another at around the same time. Later in 1927, partly in response to Jordan and Dirac and avoiding the mathematical difficulties facing their approach, John von Neumann developed the modern Hilbert space formalism of quantum mechanics. We focus on Jordan and von Neumann. Central to the formalisms of both are expressions for conditional probabilities of finding some value for one quantity given the value of another. Beyond that Jordan and von Neumann had very different views about the appropriate formulation of problems in quantum mechanics. For Jordan, unable to let go of the analogy to classical mechanics, the solution of such problems required the identification of sets of canonically conjugate variables, i.e., p's and q's. For von Neumann, not constrained by the analogy to classical mechanics, it required only the identification of a maximal set of commuting operators with simultaneous eigenstates. He had no need for p's and q's. Jordan and von Neumann also stated the characteristic new rules for probabilities in quantum mechanics somewhat differently. Jordan and Dirac were the first to state those rules in full generality. Von Neumann rephrased them and, in a paper published a few months later, sought to derive them from more basic considerations. In this paper we reconstruct the central arguments of these 1927 papers by Jordan and von Neumann and of a paper on Jordan's approach by Hilbert, von Neumann, and Nordheim. We highlight those elements in these papers that bring out the gradual loosening of the ties between the new quantum formalism and classical mechanics. This paper was written as part of a joint project in the history of quantum physics of the Max Planck

  17. Aufnahme, Analyse und Visualisierung von Bewegungen nativer Herzklappen in-vitro

    NASA Astrophysics Data System (ADS)

    Weiß, Oliver; Friedl, Sven; Kondruweit, Markus; Wittenberg, Thomas

    Die hohe Zahl an Transplantationen von Herzklappen und viele nötige Re-Operationen machen eine detaillierte Analyse der Strömungen und Klappenbewegungen klinisch interessant. Ein neuer Ansatz ist hierbei der Einsatz von Hochgeschwindigkeitskameras um Bewegungsabl äufe der Herzklappen beobachten und auswerten zu können. Die hohen Datenraten erfordern allerdings eine möglichst automatisierte Analyse und möglichst komprimierte Darstellung des Schwingungsverhaltens. In dieser Arbeit wird ein Ansatz vorgestellt, bei dem Bewegungen nativer Herzklappen in-vitro aufgenommen, analysiert und kompakt visualisiert werden.

  18. Gastrointestinal complications of von Recklinghausen's disease: two case reports and a review of the literature.

    PubMed

    Pinsk, I; Dukhno, O; Ovnat, A; Levy, I

    2003-12-01

    There are few reports of the association between neurofibromatosis (von Recklinghausen's disease) and large, solid stromal tumours of the gastrointestinal tract. The prevalence of gastrointestinal involvement in von Recklinghausen's disease has been estimated at 11%-25%. Some associated gastrointestinal stromal tumours present clinically as bowel obstruction, perforation or gastrointestinal bleeding. We recently treated two patients with this condition who presented with gastrointestinal bleeding and were diagnosed with gastrointestinal stromal tumours. We report the unique aspects of these cases and discuss the diagnostic and management problems that are posed by this unusual association.

  19. Species of Typhlophoros von Linstow, 1906 (Nematoda: Ascaridoidea) in Old World crocodilians.

    PubMed

    Sprent, J F

    1999-07-01

    A new species of the genus Typhlophoros von Linstow, 1906, T. spratti, is described from the freshwater crocodile Crocodylus johnstoni and the saltwater crocodile C. porosus in northern Australia. Specimens of the new species could not be compared with the type-species, T. lamellaris, as no preserved specimens of the latter species are known to exist. The new species differs from the descriptions of von Linstow (1906) and Maplestone (1930) in the number of interlabial ridges, the form of the ventriculus and absence of lateral alae. The taxonomic status and affinities of Typhlophoros are discussed.

  20. Human von Willebrand factor/factor VIII concentrates in the management of pediatric patients with von Willebrand disease/hemophilia A

    PubMed Central

    Castaman, Giancarlo; Linari, Silvia

    2016-01-01

    Several plasma-derived intermediate and high-purity concentrates containing von Willebrand factor (VWF) and factor VIII (FVIII) are currently available. The main role of these products in the management of the pediatric population is represented by the replacement therapy in patients with severe or intermediate forms of von Willebrand disease, in whom other treatments are ineffective or contraindicated. Another important role of VWF/FVIII concentrates in children may be their use in immune tolerance induction (ITI) protocols. ITI is particularly recommended for hemophilia A children who have developed an inhibitor against FVIII, currently the most serious complication of substitutive treatment in hemophilia. Although recombinant concentrates may represent the preferred option in children with hemophilia A, VWF/FVIII concentrates may offer an advantage in rescuing patients who failed previous ITI. PMID:27445481

  1. On the history of Ludwig von Bertalanffy's "general systemology", and on its relationship to cybernetics - Part II: Contexts and developments of the systemological hermeneutics instigated by von Bertalanffy

    NASA Astrophysics Data System (ADS)

    Pouvreau, David

    2014-02-01

    The history of "general system theory" is investigated in order to clarify its meanings, vocations, foundations and achievements. It is characterized as the project of a science of the systemic interpretation of the "real", renamed here "general systemology". The contexts and modes of its elaboration, publication and implementation are discussed. The paper mostly focuses on the works of its instigator: Ludwig von Bertalanffy. However, general systemology was a collective project: the main contributions of other "systemologists", from the 1950s until the 1970s, are hence also considered. Its solidarity with the history of the Society for General Systems Research is notably discussed. A reconstruction of the systemological hermeneutics is undertaken on this basis. It finds out the potential systematic unity underlying the diversity of the contributions to this both scientific and philosophical project. Light is thus shed on the actual scope of von Bertalanffy's works.

  2. Human von Willebrand factor/factor VIII concentrates in the management of pediatric patients with von Willebrand disease/hemophilia A.

    PubMed

    Castaman, Giancarlo; Linari, Silvia

    2016-01-01

    Several plasma-derived intermediate and high-purity concentrates containing von Willebrand factor (VWF) and factor VIII (FVIII) are currently available. The main role of these products in the management of the pediatric population is represented by the replacement therapy in patients with severe or intermediate forms of von Willebrand disease, in whom other treatments are ineffective or contraindicated. Another important role of VWF/FVIII concentrates in children may be their use in immune tolerance induction (ITI) protocols. ITI is particularly recommended for hemophilia A children who have developed an inhibitor against FVIII, currently the most serious complication of substitutive treatment in hemophilia. Although recombinant concentrates may represent the preferred option in children with hemophilia A, VWF/FVIII concentrates may offer an advantage in rescuing patients who failed previous ITI.

  3. Experimental Bullard-von Karman dynamo: MHD saturated regimes

    NASA Astrophysics Data System (ADS)

    Miralles, Sophie; Plihon, Nicolas; Pinton, Jean-François

    2014-05-01

    The dynamo instability, converting kinetic energy into magnetic energy, creates the magnetic fields of many astrophysical bodies for which the flows are highly turbulent. Those turbulent fluctuations restricts the range of parameters of numerical and theoretical predictions. As laboratory experiments are closer from natural parameters, this approach is favored in this work. In the past decades, dynamo action has been observed in experiments involving laminar flows [1] or fully turbulent flows [2] in liquid sodium. Nevertheless, the saturation of the velocity field by the Lorentz force due to the dynamo magnetic field is weak in those experiment because the control parameter is always close to the threshold of the instability (which is not the case in astrophysical situations). The details of the mechanism of the back reaction of Lorentz force on the flow are not known. We present here an experimental semi-synthetic dynamo, for which a fluid turbulent induction mechanism ('omega' effect) is associated to an external amplification applying a current into a pair of coils. The flow, called von-Karman, is produced by the counter rotation of two coaxial propellers in a cylindrical tank filled with liquid gallium. The resulting flow is highly turbulent (Re > 10 ^ 5). The amplification, mimicking a turbulent 'alpha' effect, allow to observe the dynamo instability at low magnetic Reynolds number (Rm ~ 2), far below the threshold of natural homogeneous dynamo. This experiment reaches non linear regimes, for which the saturation is a MHD process, at control parameter several times the critical value. The instability grows through an on-off intermittent regime evolving into a full MHD saturated regime for which the Lorentz force is in balance with the inertial one. The power budget is strongly modified by the dynamo magnetic field and we give an insight of the estimated rate of conversion of kinetic energy into magnetic one from experimental data. Very rich regimes such as

  4. "The captain and canon" C. W. A. von Wahl (1760-1846) (German Title: "Der Hauptmann und Kanonikus" C. W. A. von Wahl (1760-1846) )

    NASA Astrophysics Data System (ADS)

    Brosche, Peter

    Von Wahl was an active member of the group of independent scholars, who were working in the German states within Goethe's time, and who performed astrometric and geodetic observations and calculations. Here we present some cornerstones of his life; longer intervals of it took place in Allstedt south of the Harz and in Halberstadt. Small scientific assets have been preserved at the Universitäts-Sternwarte Bonn. Therein, a lecture on secular variations of the ecliptic is of singular nature.

  5. Function of von Willebrand factor after crossed bone marrow transplantation between normal and von Willebrand disease pigs: effect on arterial thrombosis in chimeras.

    PubMed Central

    Nichols, T C; Samama, C M; Bellinger, D A; Roussi, J; Reddick, R L; Bonneau, M; Read, M S; Bailliart, O; Koch, G G; Vaiman, M

    1995-01-01

    von Willebrand factor (vWF) is essential for the induction of occlusive thrombosis in stenosed and injured pig arteries and for normal hemostasis. To separate the relative contribution of plasma and platelet vWF to arterial thrombosis, we produced chimeric normal and von Willebrand disease pigs by crossed bone marrow transplantation; von Willebrand disease (vWD) pigs were engrafted with normal pig bone marrow and normal pigs were engrafted with vWD bone marrow. Thrombosis developed in the chimeric normal pigs that showed normal levels of plasma vWF and an absence of platelet vWF; but no thrombosis occurred in the chimeric vWD pigs that demonstrated normal platelet vWF and an absence of plasma vWF. The ear bleeding times of the chimeric pigs were partially corrected by endogenous plasma vWF but not by platelet vWF. Our animal model demonstrated that vWF in the plasma compartment is essential for the development of arterial thrombosis and that it also contributes to the maintenance of bleeding time and hemostasis. Images Fig. 2 Fig. 3 PMID:7708664

  6. BOOK REVIEW: Meilensteine der Astronomie - Von Aristoteles bis Hawking

    NASA Astrophysics Data System (ADS)

    Duerbeck, H. W.; Hamel, J.

    2006-12-01

    A writer, more specific a writer on the history of astronomy, might from time to time look at the collected document folders with all the research material and reprints, and might wonder: has this been all? Especially at a time when recycling is in vogue? And, perhaps with a request or an invitation to submit something, he or she might consider re-using the material before its definitive disposal. Well, such are my feelings when I looked at Jurgen Hamel's new book Milestones of Astronomy - From Aristoteles to Hawking . A slight chance for survival of medium-sized publishers like Kosmos is to offer popular books, and a title must attract potential buyers: Aristoteles means the "old" times, and as concerns the "mad scientist" of modern times, Stephen Hawking has by now dethroned Einstein. In 1998, Hamel had published a Geschichte der Astronomie - Von den Anfangen bis zur Gegenwart (History of astronomy, from the beginnings to the present), which, of course, he could not simply copy. This time, he selected some stones from his research areas - milestones, touchstones, stumbling blocks in the long road of astronomical evolution - and put them between the covers of his new book. So let us look at these (mile)stones . The reader is informed about Aristoteles on 2 pages, but his medieval interpreter Johannes de Sacrobosco gets 8 pages! Copernicus' life and achievements are described on 9 pages, closely followed by his devotee and translator Rothmann with 8 pages; Copernicus' contemporary, Peter Apian, however, gets about 13! Bessel's and Herschel's lifes and works are described on well-deserved 13 and 15 pages, while the achievements of the two Lucasian professors, Isaac Newton and Stephen Hawking, are just outlined in a single paragraph! Thus, importance is sometimes inversely proportional to text length... But let us become serious now. Why should an active historian outline, for the hundreth time, the life of Copernicus, while there are so many interesting, and often

  7. Physik gestern und heute Suprafluidität - Von den Schwierigkeiten einer Messung

    NASA Astrophysics Data System (ADS)

    Sichau, Christian

    2003-03-01

    Der Vater der Tieftemperaturphysik, Heike Kammerlingh Onnes, benötigte zu Beginn des 20. Jahrhunderts für die Verflüssigung von wenigen Litern Heliums noch mehrere Jahre, eine riesige Apparatur und viel Geld. Heute gelingt dies routinemäßig. Die Untersuchung der Materie bei tiefen Temperaturen, insbesondere zur Suprafluidität, bietet viele Überraschungen.

  8. Generalization of von Neumann analysis for a model of two discrete halfspaces : the acoustic case.

    SciTech Connect

    Haney, Matthew M.

    2006-12-01

    Evaluating the performance of finite-difference algorithms typically uses a technique known as von Neumann analysis. For a given algorithm, application of the technique yields both a dispersion relation valid for the discrete time-space grid and a mathematical condition for stability. In practice, a major shortcoming of conventional von Neumann analysis is that it can be applied only to an idealized numerical model - that of an infinite, homogeneous whole space. Experience has shown that numerical instabilities often arise in finite-difference simulations of wave propagation at interfaces with strong material contrasts. These interface instabilities occur even though the conventional von Neumann stability criterion may be satisfied at each point of the numerical model. To address this issue, I generalize von Neumann analysis for a model of two half-spaces. I perform the analysis for the case of acoustic wave propagation using a standard staggered-grid finite-difference numerical scheme. By deriving expressions for the discrete reflection and transmission coefficients, I study under what conditions the discrete reflection and transmission coefficients become unbounded. I find that instabilities encountered in numerical modeling near interfaces with strong material contrasts are linked to these cases and develop a modified stability criterion that takes into account the resulting instabilities. I test and verify the stability criterion by executing a finite-difference algorithm under conditions predicted to be stable and unstable.

  9. Acquired von Willebrand syndrome in a patient with monoclonal gammopathy of undetermined significance.

    PubMed

    Puronen, Camille E; Josephson, Neil C; Broudy, Virginia C

    2013-06-01

    Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder that typically presents as mucocutaneous bleeding in individuals with no personal or family history of bleeding disorder. Here we present a case in which a patient presented with profound epistaxis and was found to have AVWS in the setting of monoclonal gammopathy of undetermined significance (MGUS).

  10. Physical Realization of von Neumann Lattices in Rotating Bose Gases with Dipole Interatomic Interactions

    PubMed Central

    Cheng, Szu-Cheng; Jheng, Shih-Da

    2016-01-01

    This paper reports a novel type of vortex lattice, referred to as a bubble crystal, which was discovered in rapidly rotating Bose gases with long-range interactions. Bubble crystals differ from vortex lattices which possess a single quantum flux per unit cell, while atoms in bubble crystals are clustered periodically and surrounded by vortices. No existing model is able to describe the vortex structure of bubble crystals; however, we identified a mathematical lattice, which is a subset of coherent states and exists periodically in the physical space. This lattice is called a von Neumann lattice, and when it possesses a single vortex per unit cell, it presents the same geometrical structure as an Abrikosov lattice. In this report, we extend the von Neumann lattice to one with an integral number of flux quanta per unit cell and demonstrate that von Neumann lattices well reproduce the translational properties of bubble crystals. Numerical simulations confirm that, as a generalized vortex, a von Neumann lattice can be physically realized using vortex lattices in rapidly rotating Bose gases with dipole interatomic interactions. PMID:27545446

  11. Definition of the affinity of binding between human von Willebrand factor and coagulation factor VIII.

    PubMed

    Ganz, P R; Atkins, J S; Palmer, D S; Dudani, A K; Hashemi, S; Luison, F

    1991-10-15

    Factor VIII and von Willebrand factor are two plasma proteins essential for effective hemostasis. In vivo, they form a non-covalent complex whose association appears to be metal ion dependent. However, a precise definition of the nature of the molecular forces governing their association remains to be defined, as does their binding affinity. In this paper we have determined the dissociation constant and stoichiometry for Factor VIII binding to immobilized von Willebrand factor. The data demonstrate that these proteins interact saturably and with relatively high affinity. Computer assisted analyses of the Scatchard data favour a two site binding model. The higher affinity site was found to have a Kd of 62 (+/- 13) x 10(-12) M while that of the lower affinity site was 380 (+/- 92) x 10(-12) M. The density of Factor VIII binding sites (Bmax) present on von Willebrand factor was 31 (+/- 3) pM for the high affinity binding site and 46 (+/- 6) pM for the lower site, corresponding to a calculated Factor VIII: von Willebrand factor binding ratio of 1:33 and 1:23, respectively.

  12. Space: The Long-Range Future: An Interview with Jesco von Puttkamer.

    ERIC Educational Resources Information Center

    Lawler, Andrew

    1985-01-01

    Jesco von Puttkamer manages long-range planning in NASA's Office of Space Flight. He believes that space offers the opportunity to ease global tensions, help the developing world, and create a new global culture off the planet. (Author/RM)

  13. Measurement of high-departure aspheres using subaperture stitching with the Variable Optical Null (VON)

    NASA Astrophysics Data System (ADS)

    Kulawiec, Andrew; Murphy, Paul; DeMarco, Michael

    2010-10-01

    Aspheric surfaces are proven to provide significant benefits to a wide variety of optical systems, but the ability to produce high-precision aspheric surfaces has historically been limited by the ability (or lack thereof) to measure them. Traditionally, aspheric measurements have required dedicated null optics, but the cost, lead time, and calibration difficulty of using null optics has made the use of aspheres more challenging and less attractive. In the past three years, QED has developed the Subaperture Stitching Interferometer for Aspheres (SSI-A®) to help address this limitation, providing flexible aspheric measurement capability of up to 200 waves of aspheric departure from best-fit sphere. Some aspheres, however, have thousands of waves of departure. We have recently developed Variable Optical Null (VON) technology that can null much of the aspheric departure in a subaperture. The VON is automatically configurable and is adjusted to nearly null each specific subaperture of an asphere. This ability to nearly null a local subaperture of an asphere provides a significant boost in aspheric measurement capability, enabling aspheres with up to 1000 waves of departure to be measured, without the use of dedicated null optics. We outline the basic principles of subaperture stitching and VON technology, demonstrate the extended capability provided by the VON, and present measurement results from the new Aspheric Stitching Interferometer (ASI®).

  14. A newborn with very rare von Voss-Cherstvoy syndrome: a case report

    PubMed Central

    Sharma, Deepak; Gupta, Basudev; Shastri, Sweta; Sharma, Pradeep

    2016-01-01

    Introduction von Voss-Cherstvoy syndrome is a part of a group of syndromes with radial and hematologic abnormalities, and until now approximately ten cases have been reported in the literature. This syndrome is characterized by a triad of radial ray defects, occipital encephalocele, and urogenital abnormalities. Case presentation We report a neonate from Indian ethnicity who was diagnosed with von Voss-Cherstvoy syndrome. The neonate had radial ray defect, occipital encephalocele, tetralogy of Fallot, and bilateral agenesis of kidney, ureter, and bladder. The neonate was suspected to have von Voss-Cherstvoy syndrome on the basis of clinical features, which was further confirmed by fibroblast analysis showing somatic mosaicism for del(13q). Conclusion von Voss-Cherstvoy syndrome is a very rare syndrome that can be suspected on the basis of typical clinical features and confirmed by fibroblast analysis showing somatic mosaicism for del(13q). This adds a second case of this chromosome anomaly described in this syndrome. PMID:27499650

  15. [Small bowel neurofibromatosis in Von Recklinghausen's disease. A rare cause of emergency surgery].

    PubMed

    Ben Achour, Jamel; Hani, Mohamed Aziz; Bouasker, Ibtissem; Guesmi, Fethi; Zoghlami, Ayoub; Najah, Nabil

    2003-11-01

    Two cases of small bowel neurofibromatosis in patients with Von Recklinghausen's disease are reported. Diagnosis of small bowel neurofibromatosis was made on the occasion of a complication for the two cases. We insist on the difficulty of diagnosis as well as in presence or not of complications. Treatment of these most often benign tumours remains surgical based on a segmental small bowel resection.

  16. Plexiform neurofibroma of the submandibular gland in patient with von Recklinghausen's disease

    PubMed Central

    Bisher, Hassan Al; Kant, Ravi; Aldamati, Ahmed; Badar, Aysha Ahmed

    2011-01-01

    Plexiform neurofibroma of the submandibular gland is an extremely rare tumor. Herein, we report a case of plexiform neurofibroma in a patient with a von Recklinghausen's disease (NF-1) who presented with a submandibular mass mimicking a submandibular gland tumor. Complete surgical excision provides the best treatment and final diagnosis. A neurofibroma should be considered in the differential diagnosis for submandibular mass. PMID:21464877

  17. Spontaneous haemothorax: a cause of sudden death in von Recklinghausen's disease.

    PubMed Central

    Griffiths, A. P.; White, J.; Dawson, A.

    1998-01-01

    Vasculopathy is a relatively frequent but poorly recognised manifestation of von Recklinghausen's neurofibromatosis. One of its more dramatic presentations is as spontaneous haemothorax. Clinicians and pathologists should be aware of this syndrome as a cause of sudden death in patients with neurofibromatosis. Images Figure 1 Figure 2 PMID:10197217

  18. Beyond victimhood. The struggle of Munich anatomist Titus von Lanz during National Socialism.

    PubMed

    Schütz, Mathias; Waschke, Jens; Marckmann, Georg; Steger, Florian

    2015-09-01

    The article analyzes the life and career of the anatomist Titus von Lanz (1897-1967) of Munich focusing on the period of National Socialism (NS). Von Lanz lost his position as an associate professor at the Anatomical Institute of Munich University because of his marriage to a "half-Jewish" woman in 1938. In contrast to most of his colleagues affected by National Socialist measures, von Lanz had opportunities to save his career and made extensive use of them. His story is that of a complicated struggle for the continuation of his work, involving a wide range of supporters from prestigious physicians to high-ranking National Socialist officials as well as the alienation of his colleagues at the Munich department of anatomy. The article tries to clarify these developments through the presentation of his social background, his supporters, his enemies, the research he conducted during NS and von Lanz' own remembrance of these developments from the post-war period. It aims at laying out a critical appreciation of his motives and actions, thereby contributing to the understanding of individual behavior of anatomists under NS.

  19. Dr. Wernher Von Braun on Tour With U.S. congressman Armistead Seldon

    NASA Technical Reports Server (NTRS)

    1999-01-01

    U.S. representative Armistead Seldon (D.-Al) tries on an astronaut maneuvering unit mockup during a tour of the Saturn I workshop at the Marshall Space Flight center. Explaining the unit and the workshop to Representative Seldon is Dr. Wernher Von Braun, director of the Marshall Center.

  20. von Braun and Miller in the S-IVB Orbital Workshop

    NASA Technical Reports Server (NTRS)

    1968-01-01

    During a visit to the Marshall Space Flight Center (MSFC), the Congressional House Committee on Science and Astronautics toured the S-IVB workshop. Pictured here are MSFC's Dr. Wernher von Braun (standing) and Congressman Miller, Democratic representative of California (sitting on the ergometer bicycle) inside the workshop.

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

    ERIC Educational Resources Information Center

    Messling, Markus

    2008-01-01

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

  2. Charles Darwin and other great men in correspondence with Carl Wilhelm von Naegeli.

    PubMed

    Naegeli, W; Wiedemann, H R

    1993-04-15

    The great Swiss-German botanist Carl Wilhelm von Naegeli (1817-1891) was a student of Lorenz Oken, A.P. de Candolle, and Matthias Jacob Schleiden and became a key figure in "genetic" (i.e., evolutionary-developmental) biology in the mid-late 19th century. He was an expert on the hawk-weed, Hieracium and also made important contributions to microbiology. One of his many outstanding students was Carl Correns, one of the 3 rediscoverers of Mendel's work. Naegeli was an early proponent and defender of Darwin. The correspondence preserved in the Naegeli family contains many important letters between Naegeli and his contemporaries. Those from Mendel to Naegeli have passed out of the Naegeli family and were published by Correns earlier in the century. However, exceptionally notable items still in the archives of the Naegeli family include 4 surviving letters from Darwin, 2 letters from Virchow, and 10 from Justus von Liebig. In spite of a lack of appreciation of Mendel's work, we call attention to the importance of those surviving documents from an era in which very few of the greatest naturalists and founders of modern biology--including Goethe, Darwin, Galton, Agassiz, von Humboldt, von Baer--were without "blind spots."

  3. RELATIONSHIP BETWEEN FORMAL INTRA-LIST SIMILARITY AND MAGNITUDE OF THE VON RESTORFF EFFECT.

    ERIC Educational Resources Information Center

    SAMUELS, S. JAY

    TO DETERMINE WHAT EFFECT INTRALIST SIMILARITY AND STIMULUS ISOLATION WOULD HAVE ON THE VON RESTORFF EFFECT, ISOLATED STIMULUS TERMS WERE PRESENTED IN RED AND NONISOLATED STIMULUS TERMS WERE PRESENTED IN BLACK. SUBJECTS WERE 60 FIRST GRADERS. THE PAIRED-ASSOCIATE ANTICIPATION PROCEDURE WAS USED. ACQUISITION TRIALS AND TRANSFER TESTS WERE GIVEN FOR…

  4. Dr. Wernher Von Braun greeting dignitaries at the Redstone Arsenal airfield.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. George E. Mueller, center, associate administrator for manned space flight, is flanked by Dr. Wernher Von Braun, left, and Dr. Eberhard Rees at the Redstone Arsenal airstrip. the associate adminstrator was making his annual staff visit to the Marshall Space Flight Center.

  5. Spontaneous rupture of adrenal pheochromocytoma in a patient with Von Recklinghausen's disease

    PubMed Central

    Azhough, Ramin; Barband, Ali Reza; Motayagheni, Negar; Niafar, Mitra; Pourfathi, Hojjat

    2009-01-01

    Spontaneous rupture of an adrenal pheochromocytoma is extremely rare and can be lethal because of dramatic changes in the circulation. We describe a 35-year-old Iranian female with previously diagnosed von Recklinghausen's disease who suffered spontaneous rupture of an adrenal pheochromocytoma, misdiagnosed as renal colic followed by an extensive retroperitoneal hematoma, irreversible hemodynamic shock, and death. PMID:19881191

  6. Displacements Of Brownian Particles In Terms Of Marian Von Smoluchowski's Heuristic Model

    ERIC Educational Resources Information Center

    Klein, Hermann; Woermann, Dietrich

    2005-01-01

    Albert Einstein's theory of the Brownian motion, Marian von Smoluchowski's heuristic model, and Perrin's experimental results helped to bring the concept of molecules from a state of being a useful hypothesis in chemistry to objects existing in reality. Central to the theory of Brownian motion is the relation between mean particle displacement and…

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

    ERIC Educational Resources Information Center

    Wulf, Christoph

    2003-01-01

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

  8. Untersuchung der Störwirkung von LTE auf SRD Anwendungen bei 868 MHz

    NASA Astrophysics Data System (ADS)

    Welpot, M.; Wunderlich, S.; Gaspard, I.

    2014-11-01

    Moderne Hausautomatisierungssysteme, Alarmanlagen oder auch Funk-Zugangssysteme in Haus und Automobil setzen auf frei nutzbare Frequenzen in ISM/SRD-Bändern. Die rasante Zunahme an privaten und kommerziell genutzten Applikationen im SRD-Band bei 868 MHz und der Ausbau der LTE-Mobilfunknetze im Frequenzbereich unterhalb von 1 GHz ("Digital Dividend") wirft zunehmend die Frage nach der Funkverträglichkeit dieser Systeme untereinander auf. Während die SRD-Funkmodule auf eine geringe Sendeleistung von ~ +14 dBm beschränkt sind (Ralf and Thomas, 2009), beträgt die maximale LTE-Sendeleistung im Uplink nach (ETSI-Norm, 2011) +23 dBm. Zusammen mit der Einführung von LTE im Frequenzbereich unterhalb 1 GHz als DSL-Ersatz vor allem in ländlichen Gebieten, ergibt sich damit als mögliches Störszenario, dass durch die Aussendung des LTE-Endgerätes im Bereich von ca. 850 MHz die SRD-Funkverbindungen bei 868 MHz insbesondere dann gestört werden, wenn die Antennen beider Funksysteme räumlich nahe zueinander angeordnet sind und folglich nur eine geringe zusätzliche Entkopplung der Systeme bieten. In der vorliegenden Arbeit wird das LTE-Störpotential auf SRD-Empfänger praxisnah untersucht.

  9. Von recklinghausen neurofibromatosis-pachydermatocele causing lower limb gigantism: a case report.

    PubMed

    Rekha, Arcot; Gopalan, T R

    2006-03-01

    Gigantism of the lower limb can occur because of plexiform neurofibromas. This condition is seen with café au lait patches and multiple neurofibromatosis in this case of von Recklinghausen neurofibromatosis. We report our patient and review literature of this uncommon condition.

  10. Von Steuben and the German Contribution to the American Revolution: A Selective Bibliography.

    ERIC Educational Resources Information Center

    Krewson, Margrit B.

    This Library of Congress selected bibliography highlights the efforts of Baron Friedrich Wilhelm von Steuben, other German and German-American military leaders, and the Hessian auxiliary military forces in assisting the American colonies during the Revolutionary War. The booklet is divided into five parts. Part 1 provides historical information…

  11. Dr. Wernher Von Braun at the Marshall Space Flight Center's neutral buoyancy simulator.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun, Marshall Space Flight Center director, points and asks a question about the operation of the center's neutral buoyancy facility in the Manufacturing Engineering Laboratory. The facility was used to test and evaluate hardware and operations hat were planned for Apollo applications program flights.

  12. Differential localization of P-selectin and von Willebrand factor during megakaryocyte maturation.

    PubMed

    Zingariello, M; Fabucci, M E; Bosco, D; Migliaccio, A R; Martelli, F; Rana, R A; Zetterberg, E

    2010-04-28

    An important step in megakaryocyte maturation is the appropriate assembly of at least two distinct subsets of alpha-granules. The mechanism that sorts the alpha-granule components into distinct structures and mediates their release in response to specific stimuli is now emerging. P-selectin and von Willebrand factor are two proteins present in the alpha-granules that recognize P-selectin glycoprotein ligand on neutrophils and collagen in the subendothelial matrix. These proteins may play an important role in determining the differential release of the alpha-granule contents in response to external stimuli. If P-selectin and von Willebrand factor are localized in the same or different alpha-granules is not known. To clarify this question, we analyzed by immunoelectron microscopy the localization of von Willebrand factor and P-selectin during the maturation of wild-type and Gata1(low) megakaryocytes induced in vivo by treating animals with thrombopoietin. Gata1(low) is a hypomorphic mutation that blocks megakaryocyte maturation, reduces the levels of von Willebrand factor expression and displaces P-selectin on the demarcation membrane system. The maturation block induced by this mutation is partially rescued by treatment in vivo with thrombopoietin. In immature megakaryocytes, both wild-type and Gata1(low), the two receptors were co-localized in the same cytoplasmic structures. By contrast, the two proteins were segregated to separate alpha-granule subsets as the megakaryocytes matured. These observations support the hypothesis that P-selectin and von Willebrand factor may ensure differential release of the alpha-granule content in response to external stimuli.

  13. The natural history of occult or angiodysplastic gastrointestinal bleeding in von Willebrand disease.

    PubMed

    Makris, M; Federici, A B; Mannucci, P M; Bolton-Maggs, P H B; Yee, T T; Abshire, T; Berntorp, E

    2015-05-01

    Recurrent gastrointestinal bleeding is one of the most challenging complications encountered in the management of patients with von Willebrand disease (VWD). The commonest cause is angiodysplasia, but often no cause is identified due to the difficulty in making the diagnosis. The optimal treatment to prevent recurrences remains unknown. We performed a retrospective study of VWD patients with occult or angiodysplastic bleeding within the setting of the von Willebrand Disease Prophylaxis Network (VWD PN) to describe diagnostic and treatment strategies. Centres participating in the VWD PN recruited subjects under their care with a history of congenital VWD and gastrointestinal (GI) bleeding due to angiodysplasia, or cases in which the cause was not identified despite investigation. Patients with acquired von Willebrand syndrome or those for whom the GI bleeding was due to another cause were excluded. Forty-eight patients from 18 centres in 10 countries were recruited. Seven individuals had a family history of GI bleeding and all VWD types except 2N were represented. Angiodysplasia was confirmed in 38%, with video capsule endoscopy and GI tract endoscopies being the most common methods of making the diagnosis. Recurrent GI bleeding in VWD is associated with significant morbidity and required hospital admission on up to 30 occasions. Patients were treated with multiple pharmacological agents with prophylactic von Willebrand factor concentrate being the most efficient in preventing recurrence of the GI bleeding. The diagnosis and treatment of recurrent GI bleeding in congenital VWD remains challenging and is associated with significant morbidity. Prophylactic treatment with von Willebrand factor concentrate was the most effective method of preventing recurrent bleeding but its efficacy remains to be confirmed in a prospective study.

  14. Schichtübergreifende Früherkennung von Verbindungsausfällen in drahtlosen Mesh-Netzwerken

    NASA Astrophysics Data System (ADS)

    Lindhorst, Timo

    Drahtlose Mesh-Netzwerke (WMNs) bilden aufgrund ihrer Selbstorganisation ein flexibles Kommunikationssystem. Bei der Erkennung einzelner Verbindungsausfälle, die bei der Integration mobiler Teilnehmer unvermeidbar sind, ist bei aktuellen Routingprotokollen die Kommunikation jedoch für mehrere Sekunden unterbrochen. In dieser Arbeit wird gezeigt, wie durch Nutzung von Informationen aus der MAC-Schicht ein Ausfall frühzeitig erkannt und dadurch die Anzahl der Paketverluste von mehreren Hundert auf maximal vier reduziert werden kann. Hierdurch wird die Zuverlässigkeit und Verfügbarkeit von WMNs erhöht und ihr Einsatz für Echtzeit-Anwendungen ermöglicht.

  15. Detection of the CS20 Colonization Factor Antigen in Diffuse-Adhering Escherichia coli Strains

    DTIC Science & Technology

    2010-01-01

    Savarino5 & Claudio F. Lanata4•7 ’Institute de Medicina Tropical ’Alexander von Humboldt’, Universidad Peruana Cayetano Heredia, Lima, Peru; 2Umvers1ty...de C•encias Aplicadas. Lima, Peru Abstract Correspondence: Theresa J. Ochoa, Institute de Medicina Tropical ’Alexander von Humboldt’, Universidad

  16. Versuche zur Gewinnung von katalytischen Antikörpern zur Hydrolyse von Arylcarbamaten und Arylharnstoffen. (English Title: Attempts to produce catalytic antibodies for hydrolysis of arylcarbamates and arylureas)

    NASA Astrophysics Data System (ADS)

    Werner, Deljana

    2002-05-01

    Im Rahmen dieser Arbeit gelang es, katalytische Antikörper zur Hydrolyse von Benzylphenylcarbamaten sowie zahlreiche monoklonale Antikörper gegen Haptene herzustellen. Es wurden verschiedene Hapten-Protein-Konjugate unter Verwendung unterschiedlicher Kopplungsmethoden hergestellt und charakterisiert. Zur Generierung der hydrolytisch aktiven Antikörper wurden Inzuchtmäuse mit KLH-Konjugaten von 4 Übergangszustandsanaloga (ÜZA) immunisiert. Mit Hilfe der Hybridomtechnik wurden verschiedene monoklonale Antikörper gegen diese ÜZA gewonnen. Dabei wurden sowohl verschiedene Immunisierungsschemata als auch verschiedene Inzuchtmausstämme und Fusionstechniken verwendet. Insgesamt wurden 32 monoklonale Antikörper gegen die verwendeten ÜZA selektiert. Diese Antikörper wurden in groen Mengen hergestellt und gereinigt. Zum Nachweis der Antikörper-vermittelten Katalyse wurden verschiedene Methoden entwickelt und eingesetzt, darunter immunologische Nachweismethoden mit Anti-Substrat- und Anti-Produkt-Antikörpern und eine photometrische Methode mit Dimethylaminozimtaldehyd. Der Nachweis der hydrolytischen Aktivität gelang mit Hilfe eines Enzymsensors, basierend auf immobilisierter Tyrosinase. Die Antikörper N1-BC1-D11, N1-FA7-C4, N1-FA7-D12 und R3-LG2-F9 hydrolysierten die Benzylphenylcarbamate POCc18, POCc19 und Substanz 27. Der Nachweis der hydrolytischen Aktivität dieser Antikörper gelang auch mit Hilfe der HPLC. Der katalytische Antikörper N1-BC1-D11 wurde kinetisch und thermodynamisch untersucht. Es wurde eine Michaelis-Menten-Kinetik mit Km von 210 µM, vmax von 3 mM/min und kcat von 222 min-1 beobachtet. Diese Werte korrelieren mit den Werten der wenigen bekannten Diphenylcarbamat-spaltenden Abzyme. Die Beschleunigungsrate des Antikörpers N1-BC1-D11 betrug 10. Das ÜZA Hei3 hemmte die hydrolytische Aktivität. Dies beweist, dass die Hydrolyse in der Antigenbindungsstelle stattfindet. Weiter wurde zwischen der Antikörperkonzentration und der

  17. Von Willebrand disease in sub-Saharan Africa: a first severe case reported in Cameroon.

    PubMed

    Tagny, Claude T; Balôgôg, Pauline N; Boehlen, Francoise; Mbanya, Dora

    2016-10-01

    In Cameroon, the Yaoundé Hemophilia Treatment Center (HTC) has so far recorded 121 cases of hemophilia and only 10 cases of von Willebrand disease (VWD). We report the case of a 16-year-old girl, living in the north of Cameroon. She presented with severe meno-metrorrhagia, which had increased drastically within the past 3 months, associated more recently by gum bleeding and epistaxis. The coagulation screen showed a prolonged bleeding time. The clinical profile of this young girl and the findings of less than 5% for von Willebrand factor (VWF):Ag and 10% for VWF Ristocetin cofactor suggests a type 3 VWD. Screening for VWF:Ag and other inherited bleeding disorders in Cameroon is still rudimentary, and although VWD is more common than hemophilia, we report this case to highlight some of the challenges faced in resource-limited contexts.

  18. Von Neumann stability analysis of the u- p reproducing kernel formulation for saturated porous media

    NASA Astrophysics Data System (ADS)

    Chi, Sheng-Wei; Siriaksorn, Thanakorn; Lin, Shih-Po

    2017-02-01

    This paper introduces the von Neumann method to investigate the temporal stability of the displacement-pressure (u{-}p) reproducing kernel formulation for saturated porous media. Both dynamic and quasi-static formulations are considered and the critical time steps are derived. The effect of lumped and consistent matrices on temporal stability is analyzed under explicit temporal discretization. It is shown that lumped matrices have better temporal stability than consistent matrices. The study also shows that nodal support size greatly affects the critical time step size of the formulations. For consistent matrices, larger support size results in smaller critical time step size; however, opposite relation occurs if lumped scheme is used. The numerical study shows that stabilization parameter of the stabilized nodal integration methods reduces the critical time step size. Transient analyses are performed to verify the results from von Neumann analysis.

  19. Two errors in enteric epidemiology: the stories of Austin Flint and Max von Pettenkofer.

    PubMed

    Evans, A S

    1985-01-01

    The misconceptions of two physicians, Austin Flint and Max von Pettenkofer, in interpreting epidemiologic data on the water transmission of enteric disease are reviewed. Austin Flint failed to recognize the transmission of typhoid fever from well water in an epidemic he investigated in North Boston, New York, in 1843. He later discovered and freely admitted his error. Max von Pettenkofer, who had studied cholera in the 1854 outbreak and in many subsequent outbreaks, failed to confirm John Snow's observations in England on the water transmission of cholera. Pettenkofer eventually swallowed live cholera bacilli and did not develop cholera. He remained convinced to the end of his life that cholera is not directly transmitted by drinking water.

  20. [On the Awarding of the First Nobel Prize for Physiology or Medicine to Emil von Behring].

    PubMed

    Hansson, Nils; Enke, Ulrike

    2015-12-01

    In his will of 1895, the Swedish inventor Alfred Nobel laid the foundation for prizes in physics, chemistry, physiology or medicine, literature, and peace to those who had "conferred the greatest benefit on mankind" during the last year. The Nobel Prize is today widely considered as the most prestigious international symbol of scientific excellence, but it still is an exciting research question how it gained such prestige. Drawing on files from the Emil von Behring Archive in Marburg, Germany, and the Archive of the Nobel Assembly for Physiology or Medicine in Stockholm this essay aims at shedding light on why the first Nobel Prize for Physiology or Medicine in 1901 was awarded the German immunologist Emil von Behring, and how this decision was viewed at that time. This study is part of a research project that explores mechanisms leading to scientific recognition by using the example of the Nobel Prize for Physiology or Medicine.

  1. Current controversies in the diagnosis and management of von Willebrand disease

    PubMed Central

    2015-01-01

    Von Willebrand disease (VWD) is the most common inherited bleeding disorder in the world. The spectrum of VWD spans quantitative and qualitative deficiencies of von Willebrand factor (VWF), a platelet adhesive protein. It manifests primarily as mucocutaneous bleeding, but severely affected patients may suffer soft tissue bleeding and hemarthroses. There is disagreement in the multiple guidelines published regarding diagnosis, especially of type 1 VWD, which also remains the most opaque with respect to molecular characterization. Treatment with desmopressin (DDAVP) is most effective in type 1 VWD, but regimens are not standardized. It is not clear which type 2 VWD patients with qualitative deficiencies can be treated with DDAVP and which ones should receive VWF concentrates. No guidelines stipulate which patients might benefit from prophylactic VWF infusions and how they should be dosed. These are some current controversies in VWD that are discussed in this review. PMID:26288715

  2. L'atteinte vésicale au cours de la neurofibromatose de Von Recklinghausen

    PubMed Central

    Benazzouz, Mohamed Hicham; Hajjad, Tilila; Essatara, Younes; El Sayegh, Hachem; Iken, Ali; Benslimane, Lounis; Nouini, Yassine

    2014-01-01

    La neurofibromatose de type 1 ou maladie de Von Recklinghausen est une maladie génétique autosomique dominante en rapport avec des mutations dans le gène suppresseur de tumeur NF1. L'atteinte uro-génitale au cours de cette maladie est rare et moins de 80 cas ont été rapportés à ce jour dans la littérature mondiale. Les auteurs rapportent un nouveau cas d'atteinte vésicale découverte fortuitement au cours du suivi d'une patiente atteinte de la maladie de Von Recklinghausen. A travers cette observation et une revue de la littérature les auteurs discutent également les difficultés diagnostiques, thérapeutiques ainsi que les modalités de suivi dans cette maladie. PMID:25328590

  3. Jahre Entwicklung der Instandhaltung - von der ausfallorientierten Instandhaltung zum gemeinsamen TPM und RCM

    NASA Astrophysics Data System (ADS)

    Iske, Friedhelm

    Zur Einleitung meines Beitrages möchte ich von einem Gespräch mit einem Mitarbeiter berichten, das ich als junger Vorgesetzter einer Instandhaltungsgruppe 1988 führte. Der engagierte Mitarbeiter feierte damals sein vierzigjähriges Dienstjubiläum und war stolz auf das von ihm Geleistete sowie auf den besonderen Einsatz seiner Altersgruppe, die nach dem Zweiten Weltkrieg das Werk wieder aufgebaut hatte. Auf meine Frage, was denn damals die erste Aufgabe in der Firma war, bekam ich kurz und knapp und mit einer Selbstverständlichkeit die selbstbewusste Antwort: "Unser Pferd füttern und mit dem Pferd die innerbetrieblichen Transporte erledigen“. Als junger, technisch orientierter Vorgesetzter war ich über diese Antwort sehr überrascht. Gedanklich weit entfernt war die Vorstellung, dass in der Vergangenheit Transporte mit einem Pferd erledigt wurden.

  4. Numerical study of homogeneous dynamo based on experimental von Kármán type flows

    NASA Astrophysics Data System (ADS)

    Marié, L.; Burguete, J.; Daviaud, F.; Léorat, J.

    2003-06-01

    A numerical study of the magnetic induction equation has been performed on von Kármán type flows. These flows are generated by two co-axial counter-rotating propellers in cylindrical containers. Such devices are currently used in the von Kármán sodium (VKS) experiment designed to study dynamo action in an unconstrained flow. The mean velocity fields have been measured for different configurations and are introduced in a periodic cylindrical kinematic dynamo code. Depending on the driving configuration, on the poloidal to toroidal flow ratio and on the conductivity of boundaries, some flows are observed to sustain growing magnetic fields for magnetic Reynolds numbers accessible to a sodium experiment. The response of the flow to an external magnetic field has also been studied: The results are in excellent agreement with experimental results in the single propeller case but can differ in the two propellers case.

  5. Refractory bleeding from intestinal angiodysplasias successfully treated with danazol in three patients with von Willebrand disease.

    PubMed

    Botero, Juliana Perez; Pruthi, Rajiv K

    2013-12-01

    von Willebrand disease (VWD) is associated with development of gastrointestinal (GI) vascular malformations that lead to chronic GI bleeding. Conventional management, including von Willebrand factor concentrate replacement and endoscopic ablation or bowel resection, does not consistently reduce hemorrhage. We describe three patients with VWD for whom conventional management failed to control GI bleeding. We retrospectively reviewed medical records of patients with VWD and GI bleeding. After patients began treatment with danazol, we observed long-term reductions in GI bleeding and packed red blood cell transfusion requirements. One patient had severe liver toxicity and was found to have concomitant primary biliary cirrhosis. Danazol use may be considered in patients with VWD and GI bleeding due to angiodysplasia that otherwise fails to respond to conventional treatment; the primary aim of treatment is to reduce transfusion dependence. The benefits are variable and possibly transient. Monitoring for toxicity is important when this treatment is pursued.

  6. Instrumentation for Studies of Cochlear Mechanics: From von Békésy forward

    PubMed Central

    Nuttall, Alfred L; Fridberger, Anders

    2012-01-01

    Georg von Békésy designed the instruments needed for his research. He also created physical models of the cochlea allowing him to manipulate the parameters (such as volume elasticity) that could be involved in controlling traveling waves. This review is about the specific devices that he used to study the motion of the basilar membrane thus allowing the analysis that lead to his Nobel Prize Award. The review moves forward in time mentioning the subsequent use of von Békésy’s methods and later technologies important for motion studies of the organ of Corti. Some of the seminal findings and the controversies of cochlear mechanics are mentioned in relation to the technical developments. PMID:22975360

  7. Von Willebrand Factor Abnormalities Studied in the Mouse Model: What We Learned about VWF Functions

    PubMed Central

    Casari, Caterina; Lenting, Peter J.; Christophe, Olivier D.; Denis, Cécile V.

    2013-01-01

    Up until recently, von Willebrand Factor (VWF) structure-function relationships have only been studied through in vitro approaches. A powerful technique known as hydrodynamic gene transfer, which allows transient expression of a transgene by mouse hepatocytes, has led to an important shift in VWF research. Indeed this approach has now enabled us to transiently express a number of VWF mutants in VWF-deficient mice in order to test the relative importance of specific residues in different aspects of VWF biology and functions in an in vivo setting. As a result, mice reproducing various types of von Willebrand disease have been generated, models that will be useful to test new therapies. This approach also allowed a more precise identification of the importance of VWF interaction with subendothelial collagens and with platelets receptors in hemostasis and thrombosis. The recent advances gathered from these studies as well as the pros and cons of the technique will be reviewed here. PMID:23936618

  8. Synthese von analogen Filtern auf einer rekonfigurierbaren Hardware-Architektur mittels eines Genetischen Algorithmus

    NASA Astrophysics Data System (ADS)

    Trendelenburg, S.; Becker, J.; Henrici, F.; Manoli, Y.

    2008-05-01

    Rekonfigurierbare Analog-Arrays (FPAAs) sind der Versuch, die Vorteile der aus der digitalen Welt bekannten FPGAs (Flexibilität, Entwurfsgeschwindigkeit) auch für analoge Anwendungen verfügbar zu machen. Aufgrund der Vielfalt der analogen Schaltungstechnik ist die Abbildung von vorgegebenen Schaltungskonzepten auf eine FPAA-Architektur nicht immer einfach lösbar. Diese Arbeit stellt einen neuen Ansatz für die Synthese von Filtern auf einer FPAA-Architektur für zeitkontinuierliche Analogfilter mittels eines Genetischen Algorithmus (GA) vor. Anhand eines Matlab-Modells des FPAA, das eine gute übereinstimmung mit Simulationen des FPAA auf Transistorebene aufweist, wurde gezeigt, dass eine große Vielzahl verschiedener Filterstrukturen auf dieser Architektur dargestellt werden kann. Daraufhin wurde ein Genetischer Algorithmus entwickelt, der es erlaubt, aus einer gegebenen Filterspezifikation Konfigurationsdatensätze zu synthetisieren, die den gewünschten Filter auf die FPAA-Architektur abbilden.

  9. Acquired von Willebrand disease and multiple myeloma: a case report of a breast cancer survivor.

    PubMed

    Jin, Ning; Salahuddin, Farah F; Nesbitt, John A

    2014-12-01

    Acquired von Willebrand disease (aVWD) is rare disease and is associated with a variety of underlying diseases. We report a case of aVWD in the setting of multiple myeloma. The patient was a 63-year-old female with breast cancer in remission who was admitted for symptomatic anemia. She was diagnosed with multiple myeloma. She also had subcutaneous bleeding before admission. Laboratory studies revealed isolated prolongation of the activated partial thromboplastin time, which corrected in a mixing study. Her factor VIII activity, von Willebrand factor (VWF) Ag, and VWF activity were low. VWF multimer study confirmed the patient had aVWD. The treatment of aVWD is discussed in this article, including the treatment of underlying diseases, and acute management in emergent situations. An intriguing question in this case is whether the patient's multiple myeloma is a chemotherapy-induced hematological malignancy or a second primary malignancy.

  10. Von Willebrand disease - the 'Dos' and 'Don'ts' in surgery.

    PubMed

    Miesbach, Wolfgang; Berntorp, Erik

    2017-02-01

    Von Willebrand disease (VWD) is the most common genetic bleeding disorder. VWD is caused by a deficiency or dysfunction of von Willebrand factor (VWF), a plasma protein that mediates the initial adhesion of platelets at sites of vascular injury and binds and stabilises coagulation factor VIII (FVIII) in the blood. Prophylaxis of surgical bleeding in patients with VWD requires consideration of the individual situation, including the type of procedure and the bleeding rate, before decisions about treatment type, dose, duration and adjunctive therapy with antifibrinolytics or antithrombotic prophylaxis can be made. Although desmopressin (DDAVP)-stimulated release of endogenous VWD is an effective treatment strategy in many patients, plasma concentrates containing VWF are the preferred option for most patients undergoing surgical procedures. Recommendations for the management of surgery in patients with VWD are summarised, including the severity of VWD and the type of the surgical procedure.

  11. Type 2M and Type 2A von Willebrand Disease: Similar but Different.

    PubMed

    Favaloro, Emmanuel J; Pasalic, Leonardo; Curnow, Jennifer

    2016-07-01

    Analogous to the differentiation between hemophilia A and B, respectively, reflecting deficiency in factor VIII (FVIII) and FIX, and increasing being recognized as reflecting clinically different disorders, types 2A and 2M von Willebrand disease (VWD) can also be shown to express both similarities and differences in their prevalence, genetic defects, laboratory test results, clinical features, and treatment responses. In this narrative review, we explore these two "subtypes" of type 2 VWD, identifying parallels and dissimilarities in various aspects of their presentation to clinicians and to scientists/laboratories. This differential will become increasingly important as we strive to provide personalized approaches to future management of patients with VWD, particularly in the emerging landscape of recombinant von Willebrand factor.

  12. Up to date concepts about Von Willebrand disease and the diagnose of this hemostatic disorder

    PubMed Central

    Buga-Corbu, I; Arion, C

    2014-01-01

    Abstract The authors review the current data in literature regarding the recent knowledge about hemostase, coagulation and clinical and laboratory diagnostic algorithms of hemostatic disorders. They also present the pathological classification of bleeding disorders - the basis to clinical approach of these diseases. Abbreviations: AD=autosomal dominant; Ag=antigen; DNA=deoxyribonucleic acid; ADAMTS13=serum metalloproteinase; AR=autosomal recessive; Arg=arginine; RNA=ribonucleic acid; VWD=von Willebrand disease; Cys=cysteine; C1—C9=factors of the seric complement; ELISA=enzyme linked immuno assay; FI---FXIII=plasmatic factors of coagulation; Glu=glutamines; Pg=platelet glycoprotein; HMW=high molecular weight; IL=interleukin; SLE=systemic lupus erythematosus; Met=methionine; PFA=automated study test of platelets aggregation; RCo=ristocetin cofactor; RI PA=ristocetin induced platelet aggregation; Tyr=tyrosine; VWF= von Willebrand factor PMID:25408749

  13. Instrumentation for studies of cochlear mechanics: from von Békésy forward.

    PubMed

    Nuttall, Alfred L; Fridberger, Anders

    2012-11-01

    Georg von Békésy designed the instruments needed for his research. He also created physical models of the cochlea allowing him to manipulate the parameters (such as volume elasticity) that could be involved in controlling traveling waves. This review is about the specific devices that he used to study the motion of the basilar membrane thus allowing the analysis that lead to his Nobel Prize Award. The review moves forward in time mentioning the subsequent use of von Békésy's methods and later technologies important for motion studies of the organ of Corti. Some of the seminal findings and the controversies of cochlear mechanics are mentioned in relation to the technical developments.

  14. Papillary neoplasm of the endolymphatic sac in a patient with von Hippel-Lindau disease.

    PubMed Central

    Delisle, M B; Uro, E; Rouquette, I; Yardeni, E; Rumeau, J L

    1994-01-01

    Glandular tumours involving the middle ear and the mastoid are rare, and distinguishing between adenoma and adenocarcinoma is difficult. Two distinct histopathological patterns are accepted. While their clinical presentation differs, both require primary surgical treatment and both have a high rate of local recurrence. The papillary form takes a more aggressive course and wider regional spread. This pattern occurs predominantly in women. Its microscopic appearance and clinical course have been extensively described by Heffner who considered it as "low-grade adenocarcinoma of probable endolymphatic sac origin". A few cases have been associated with von Hippel-Lindau disease. The case of a 32 year old black woman is described. It is suggested that papillary adenocarcinoma of the endolymphatic sac should be considered in the spectrum of neoplasms seen in von Hippel-Lindau disease. Images PMID:7962613

  15. Deafness due to bilateral endolymphatic sac tumours in a case of von Hippel-Lindau syndrome.

    PubMed Central

    Kempermann, G; Neumann, H P; Scheremet, R; Volk, B; Mann, W; Gilsbach, J; Laszig, R

    1996-01-01

    A case of bilateral endolymphatic sac tumours is reported. In a patient with von Hippel-Lindau syndrome, tumour growth in the right cerebellopontine angle caused deafness. The tumour was removed and classified as a metastasis from a thyroid carcinoma. However, on thyroidectomy no primary neoplasm could be found. Eight years later a similar tumour was operated on in the left petrosal bone. Histological appearance, immunocytochemical findings, and the clinical context gave evidence that the tumours had to be reclassified as endolymphatic sac tumours--extremely rare entities. The report supports the hypothesis, suggested by the few earlier case reports, that endolymphatic sac tumours could be one of the inherent tumour manifestations in von Hippel-Lindau syndrome. Images PMID:8795608

  16. A Case of Acute Generalized Pustular Psoriasis of von Zumbusch Triggered by Hypocalcemia

    PubMed Central

    Guerreiro de Moura, Carlos Antônio Gusmão; de Assis, Luiz Henrique; Góes, Paulo; Rosa, Fabiana; Nunes, Victor; Gusmão, Ítalo Magalhães; Cruz, Constança Margarida Sampaio

    2015-01-01

    Psoriasis is an autoimmune disease triggered by different conditions in genetically susceptible people. It is characterized by variable cutaneous manifestations including localized or disseminated pustules. Generalized pustular psoriasis (GPP) has two main clinical forms: von Zumbusch psoriasis, characterized by severe erythrodermia and scaling skin after the resolution of pustules, and the annular form. GPP may also present severe extracutaneous manifestations including pneumonitis, heart failure and hepatitis. Old reports showed a relationship between hypoparathyroidism and hypocalcemia as triggers for GPP highlighting the importance of adequate workup of the patient and possible therapeutic changes in acute situations. Here, we present a case of severe von Zumbusch psoriasis with life-threatening complications triggered by severe hypocalcemia secondary to hypoparathyroidism successfully treated with aggressive calcium reposition. PMID:26955330

  17. Method of characteristics for the 3D perfect plasticity problem with the von Mises yield criterion

    NASA Astrophysics Data System (ADS)

    Verveyko, N. D.; Kuptsov, A. V.

    2009-04-01

    We present a linearized system of partial differential equations for the three-dimensional perfect plasticity problem with the von Mises yield criterion. We construct the characteristics of the three-dimensional problem, obtain differential relations along the characteristic planes, and devise a consistent stable finite-difference scheme. The use of conditions on the stress discontinuity surfaces permits simultaneously solving the Cauchy, Goursat, and mixed problems.

  18. [The Graefe memorial stone--in memory of A. von Graefe's contributions in Heiden].

    PubMed

    Koelbing, H M; Speiser, P

    1990-01-01

    Between 1859 and 1869, Albrecht von Graefe used to spend some weeks in September in Heiden, a small health resort in Eastern Switzerland. During his "holidays", however, the hotel "Freihof", where he lived, was transformed into a most active unit of ophthalmic surgery. A memorial stone, rediscovered and restored thanks to the endeavour of Professor Peter Speiser of St. Gallen, remembers this episode, which was of some importance not only for local tourism, but also for the young Swiss ophthalmology of the time.

  19. A vinylic Rosenmund-von Braun reaction: practical synthesis of acrylonitriles.

    PubMed

    Pradal, Alexandre; Evano, Gwilherm

    2014-10-14

    An efficient system based on acetone cyanohydrin and catalytic amounts of copper(I) iodide and 1,10-phenanthroline is reported for the cyanation of alkenyl iodides. A wide range of polysubstituted acrylonitriles could be obtained in fair to good yields and with complete retention of the geometry of the double bond. This extension of the Rosenmund-von Braun reaction also enabled a straightforward formal synthesis of the naturally occurring acrylonitrile alliarinoside.

  20. 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.

  1. Neurofibrosarcoma of the radial nerve in von Recklinghausen's disease with metastatic angiosarcoma.

    PubMed Central

    Macaulay, R A

    1978-01-01

    A case of von Recklinghausen's disease with multiple neurofibromatosis is described in which death was caused by intracerebral haemorrhage due to metastatic angiosarcoma. The primary site was a peripheral nerve tumour which, on microscopic examination, showed both angiosarcoma and neurofibrosarcoma with transitional zones between the two. This is interpreted as another example of divergent differentiation in malignant nerve sheath tumours, and the case is compared with the two similar examples found in the literature. Images PMID:96219

  2. Tumors perturbing extracellular matrix biosynthesis. The case of von Recklinghausen's disease.

    PubMed

    Robert, L

    2014-04-01

    This is a short review of neurofibromatosis-1 or von Recklinghausen's disease, due to a loss of function mutation of the gene neurofibromin-1, which normally inhibits the Ras MAPK-pathways. Among its symptoms, the strong oversynthesis of several collagen types designates this disease as producing a deregulation of extracellular matrix biosynthesis involved in tumor formation. Up to about 40% of the skin tumors consist of collagens. A short summary of the clinical manifestations and pathological and genetic mechanisms are also described.

  3. Effects of Multiple Cylinders on the Formation of Von Karman Vortex Streets.

    DTIC Science & Technology

    1983-12-01

    crossmember which was attached to the sides of the water table structure. The lens fixture could be adjusted for focusing of the test sec- tion image (Fig. 9...80 vii List of Tables Table Page I. Nozzle/Cylinder modifications . . .. .. .... 36 II. Hot Film Measurement Test Points for Cylinder...withSpace . .. .. .. .. ...... 42 III. Hot Film Measurement Test Points for von Karma’n Vortex Street .. . .. .. .. . .47 viii List of Symbols Symbol

  4. An efficient method for calculating RMS von Mises stress in a random vibration environment

    SciTech Connect

    Segalman, D.J.; Fulcher, C.W.G.; Reese, G.M.; Field, R.V. Jr.

    1998-02-01

    An efficient method is presented for calculation of RMS von Mises stresses from stress component transfer functions and the Fourier representation of random input forces. An efficient implementation of the method calculates the RMS stresses directly from the linear stress and displacement modes. The key relation presented is one suggested in past literature, but does not appear to have been previously exploited in this manner.

  5. ["Because the mole sometimes shows itself" argumentative structures in Hildegard von Bingen 'causeae et curae'].

    PubMed

    Riha, Ortrun

    2011-01-01

    The paper examines the didactic strategies in Hildegard von Bingen's 'Causae et curae'. Based on her self-developed, complicated concept of primary qualities, elements, and body fluids, she connects cosmic processes with physical activities and disease patterns. Hildegard combines an allopathic and a homoeopathic approach and, as an attentive observer of nature, she looks upon everyday situations as signatures of healing. Hildegard's imagination in analogy and comparison constitutes a specific quality of her medical advice.

  6. Kamera-basierte Erkennung von Geschwindigkeitsbeschränkungen auf deutschen Straen

    NASA Astrophysics Data System (ADS)

    Nienhüser, Dennis; Ziegenmeyer, Marco; Gumpp, Thomas; Scholl, Kay-Ulrich; Zöllner, J. Marius; Dillmann, Rüdiger

    An Fahrerassistenzsysteme im industriellen Einsatz werden hohe Anforderungen bezüglich Zuverlässigkeit und Robustheit gestellt. In dieser Arbeit wird die Kombination robuster Verfahren wie der Hough-Transformation und Support-Vektor-Maschinen zu einem Gesamtsystem zur Erkennung von Geschwindigkeitsbeschränkungen beschrieben. Es setzt eine Farbvideokamera als Sensorik ein. Die Evaluation auf Testdaten bestätigt durch die ermittelte hohe Korrektklassifikationsrate bei gleichzeitig geringer Zahl Fehlalarme die Zuverlässigkeit des Systems.

  7. Laparoscopic partial adrenalectomy for recurrent pheochromocytoma in a boy with Von Hippel-Lindau disease.

    PubMed

    Nambirajan, Thiagarajan; Bagheri, Fairborz; Abdelmaksoud, Alaa; Leeb, Karl; Neumann, Hartmut; Graubner, Ulrike B; Janetschek, Günter

    2004-08-01

    We describe a case of a boy with Von Hippel-Lindau disease who presented with recurrent right adrenal pheochromocytoma 4.5 years after laparoscopic bilateral partial adrenalectomy. The boy had a second laparoscopic adrenal-sparing removal of the tumor. By this technique, not only the recurrent tumor was successfully removed but also the unaffected adrenal cortex could be preserved for the second time. To our knowledge, this is the first published case of its type.

  8. Differential proteolytic activation of factor VIII-von Willebrand factor complex by thrombin

    SciTech Connect

    Hill-Eubanks, D.C.; Parker, C.G.; Lollar, P. )

    1989-09-01

    Blood coagulation factor VIII (fVIII) is a plasma protein that is decreased or absent in hemophilia A. It is isolated as a mixture of heterodimers that contain a variably sized heavy chain and a common light chain. Thrombin catalyzes the activation of fVIII in a reaction that is associated with cleavages in both types of chain. The authors isolated a serine protease from Bothrops jararacussu snake venom that catalyzes thrombin-like heavy-chain cleavage but not light-chain cleavage in porcine fVIII as judged by NaDodSO{sub 4}/PAGE and N-terminal sequence analysis. Using a plasma-free assay of the ability of activated {sup 125}I-fVIII to function as a cofactor in the activation of factor X by factor IXa, they found that fVIII is activated by the venom enzyme. The venom enzyme-activated fVIII was isolated in stable form by cation-exchange HPLC. von Willebrand factor inhibited venom enzyme-activated fVIII but not thrombin-activated fVIII. These results suggest that the binding of fVIII to von Willebrand factor depends on the presence of an intact light chain and that activated fVIII must dissociate from von Willebrand factor to exert its cofactor effect. Thus, proteolytic activation of fVIII-von Willebrand factor complex appears to be differentially regulated by light-chain cleavage to dissociate the complex and heavy-chain cleavage to activate the cofactor function.

  9. ["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".

  10. [Zurich physician-pharmacist family Lavater and Johann Wolfgang von Goethe].

    PubMed

    Mannetstätter, A; Friedrich, C

    1998-01-01

    The aim of this paper is to demonstrate the connections between Johann Wolfgang von Goethe (1749-1832) and the physician and pharmacist family Lavater in Zurich. The analysis of the correspondence between Johann Bartholomäus Trommsdorff (1770-1837) and the Lavater family and between the Lavater family and the government of the duchy of Weimar shows an interesting story about a picture "Goethe in Italy".

  11. Dr. von Braun and Dr. Stuhlinger With a Model of the Nuclear-Electric Vehicles

    NASA Technical Reports Server (NTRS)

    2004-01-01

    In this photo, taken at the Walt Disney Studios in California, Dr. Wernher von Braun and Dr. Ernst Stuhlinger are shown discussing the concepts of nuclear-electric spaceships designed to undertake the mission to the planet Mars. As a part of the Disney 'Tomorrowland' series on the exploration of space, the nuclear-electric vehicles were shown in the last three television films, entitled 'Mars and Beyond,' which first aired in December 1957.

  12. [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.

  13. Changes in bleeding patterns in von Willebrand disease after institution of long-term replacement therapy: results from the von Willebrand Disease Prophylaxis Network.

    PubMed

    Holm, Elena; Abshire, Thomas C; Bowen, Joel; Álvarez, M Teresa; Bolton-Maggs, Paula; Carcao, Manuel; Federici, Augusto B; Gill, Joan Cox; Halimeh, Susan; Kempton, Christine; Key, Nigel S; Kouides, Peter; Lail, Alice; Landorph, Andrea; Leebeek, Frank; Makris, Michael; Mannucci, Pier; Mauser-Bunschoten, Eveline P; Nugent, Diane; Valentino, Leonard A; Winikoff, Rochelle; Berntorp, Erik

    2015-06-01

    Clinically, the leading symptom in von Willebrand disease (VWD) is bleeding, chiefly of mucosal type, for example, epistaxis, gingival, or gastrointestinal bleeding, and menorrhagia. In severe forms of VWD with secondary deficiency of factor VIII, spontaneous joint bleeding, resembling that observed in severe haemophilia A, may also be observed. The bleeding patterns of VWD can affect quality of life, and may be life-threatening. The von Willebrand Disease Prophylaxis Network is an international study group formed with the goal of investigating the role of prophylaxis in clinically severe VWD. The objective of the present study is to investigate the response to prophylaxis focusing primarily on epistaxis, joint bleeding, gastrointestinal bleeding, and heavy bleeding associated with menses. Data from 105 subjects, 10 enrolled in a prospective study and 95 in a retrospective study between 2008 and 2013, were available for analysis. The median annualized rate reductions in bleeding were significant for epistaxis (P < 0.0001), gastrointestinal bleeding (P = 0.0003), joint bleeding (P < 0.0001), and menorrhagia (P = 0.008). Doses on a group level were approximately the same prior to and during prophylaxis, but more patients with gastrointestinal bleeding had prophylaxis three or more times per week as well as higher dosages. Our study, which primarily used retrospective data, indicates that prospective studies are needed to better delineate the doses and dose intervals that should be used for prophylactic treatment of VWD.

  14. Characterization of the von Willebrand factor gene (VWF) in von Willebrand disease type III patients from 24 families of Swedish and Finnish origin

    SciTech Connect

    Zhang, Z.P.; Blomback, M.; Egberg, N.; Falk, G.; Anvret, M. )

    1994-05-01

    Twenty-four patients with von Willebrand disease type III were screened for mutations in the von Willebrand factor (VWF) gene using the PCR technique, followed by direct sequencing. More than 250 kb of genomic DNA were sequenced, including the promoter and coding regions (52 exons) of the VWF gene from 24 patients. In addition to the previously reported mutations of a single cytosine deletion in exon 18 and the nonsense mutations in exons 28, 32, and 45, nine new mutations were detected: two nonsense mutations in exons 15 and 16, one allele with a thymidine insertion in exon 14, one allele with a cytosine insertion in exon 28, one 20-bp deletion in exon 15, one mutation in the donor splice site of exon 43, and three missense mutations in exons 28, 49, and 51. Forty-two mutant chromosomes were identified (42/48); 11 probands are homozygous for the mutations, and 8 are compound heterozygous. In addition, a new subfamily of the Alu sequence in the promoter region and 10 new polymorphisms were identified. 15 refs., 3 figs., 3 tabs.

  15. Isoelectric focusing of human von Willebrand factor in urea-agarose gels

    SciTech Connect

    Fulcher, C.A.; Ruggeri, Z.M.; Zimmerman, T.S.

    1983-02-01

    An analytical technique has been developed for the isoelectric focusing (IEF) of plasma von Willebrand factor (vWF) in agarose gels containing urea. Under these conditions, vWF freely enters the gel and focuses without artifact. The focused vWF is visualized by staining fixed gels with /sup 125/I-labeled affinity-purified heterologous antibody. Utilizing a pH gradient of 5.0-6.5, normal vWF in plasma or purified preparations focuses into at least three bands with apparent isoelectric points (pI) between pH 5.7 and 5.9. A reproducible difference in the IEF pattern of vWF has been established between normal plasmas and those of individuals with variant von Willebrand's disease (vWd) type IIA and type IIB. In type IIA, vWF has a distinctly lower pI than normal. This difference may be related to the presence of smaller vWF multimers in IIA plasma because forms of vWF of corresponding size contained in normal cryoprecipitate supernatant have a similar pI. Type IIB von Willebrand factor has a pI intermediate between normal and IIA. Neuraminidase treatment of plasma samples before IEF results in an increase in pI in normal, type IIA, and type IIB vWF. The data suggest that none of the 16 type IIA and 9 IIB plasmas studied here contain significantly decreased amounts of sialic acid.

  16. Critical assessment of von Mises distribution and an infinite series ansatz for self-propelled particles

    NASA Astrophysics Data System (ADS)

    Kürsten, Rüdiger; Ihle, Thomas

    2017-03-01

    We consider a Vicsek model of self-propelled particles with bounded confidence, where each particle interacts only with neighbors that have a similar direction. Depending on parameters, the system exhibits a continuous or discontinuous polar phase transition from the isotropic phase to a phase with a preferred direction. In a recent paper (Lam, Schindler and Dauchot 2015 J. Stat. Mech. P10017) the von Mises distribution was proposed as an ansatz for polar ordering. In the present system the time evolution of the angular distribution can be solved in Fourier space. We compare the results of the Fourier analysis with the ones obtained by using the von Mises distribution ansatz. In the latter case the qualitative behavior of the system is recovered correctly. However, quantitatively there are serious deviations. We introduce an extended von Mises distribution ansatz such that a second term takes care of the next two Fourier modes. With the extended ansatz we find much better quantitative agreement. As an alternative approach we also use a Gaussian and a geometric series ansatz in Fourier space. The geometric series ansatz is analytically handable but fails for very weak noise, the Gaussian ansatz yields better results but it is not analytically treatable.

  17. An Alternative to Von Glasersfeld's Subjectivism in Science Education: Deweyan Social Constructivism

    NASA Astrophysics Data System (ADS)

    Garrison, Jim

    An influential view of constructivism in science and mathematics educational research and practice is that of Ernst von Glasersfeld. It is a peculiarly subjectivist form of constructivism that should not be attractive to science and mathematics educators concerned with retaining some sort of realism that leaves room for objectivity. The subjectivist constructivism of von Glasersfeld also becomes entangled in untenable mind/body and subject/object dualisms. Finally, these dualisms are unnecessary for social constructivism. I will provide one example of a social constructivist alternative to social constructivism, that of the pragmatic philosopher JohnDewey. In presenting Deweys position I will appeal to Ockhams razor, that is, the admonition not to multiply entities beyond necessity, to shave off the needless mentalistic and psychic entities that lead von Glasersfeld into his subjectivism and dualism.In outward forms, experimental science is infinitely varied. In principle, it is simple. We know an object when we knowhow it is made, and we know how it is made in the degree in which we ourselves make it.

  18. From Mill via von Kries to Max Weber: Causality, Explanation, and Understanding

    NASA Astrophysics Data System (ADS)

    Heidelberger, Michael

    In the second part of his "Critical studies in the logic of the cultural sciences" published in 1906, which carries the title "Objective possibility and adequate causation in historical explanation" (Weber 1906, 164-188/266-290)1 Max Weber (1864-1920) wrote that he feels "almost embarrassed in view of the extent to which here again, as in so much of the preceding argument, I am 'plundering' von Kries' ideas" (Weber 1906, 186/288).2 Weber thus admits a very strong influence on his approach by the physiologist, philosopher, and theoretician of probability, von Kries (1853-1928), who was for sometime his colleague in Freiburg in southwest Germany. Von Kries had suggested a legal criterion for attributing a deed to an agent that exerted a strong influence on German civil law and was also taken up by the legal system of other countries. This earned him the title of an honorary doctor of the law faculty of the University of Erlangen in 1897.

  19. Creating von Laue patterns in crystal scattering with partially coherent sources

    NASA Astrophysics Data System (ADS)

    Wang, Yangyundou; Kuebel, David; Visser, Taco D.; Wolf, Emil

    2016-09-01

    When spatially coherent radiation is diffracted by a crystalline object, the field is scattered in specific directions, giving rise to so-called von Laue patterns. We examine the role of spatial coherence in this process. Using the first-order Born approximation, a general analytic expression for the far-zone spectral density of the scattered field is obtained. This equation relates the coherence properties of the source to the angular distribution of the scattered intensity. We apply this result to two types of sources. Quasihomogeneous Gaussian Schell-model sources are found to produce von Laue spots whose size is governed by the effective source width. Delta-correlated ring sources produce von Laue rings and ellipses instead of point-like spots. In forward scattering, polychromatic ellipses are created, whereas in backscattering striking, overlapping ring patterns are formed. We show that both the directionality and the wavelength-selectivity of the scattering process can be controlled by the state of coherence of the illuminating source.

  20. How I treat type 2 variant forms of von Willebrand disease.

    PubMed

    Tosetto, Alberto; Castaman, Giancarlo

    2015-02-05

    Type 2 von Willebrand disease (VWD) includes a wide range of qualitative abnormalities of von Willebrand factor structure and function resulting in a variable bleeding tendency. According to the current classification, 4 different subtypes can be identified, each with distinctive phenotypic and therapeutic characteristics. Current available laboratory methods allow a straightforward approach to VWD subtyping, and although the precise molecular characterization remains complex, it is not required for appropriate treatment of the vast majority of cases. Desmopressin can be useful only in a few type 2 cases compared with patients with actual quantitative deficiency (type 1), most often in variants with a nearly normal multimeric pattern (type 2M). However, since no laboratory test accurately predicts response to desmopressin, a trial test should always be performed in all type 2 VWD patients, with the exception of type 2B ones. Replacement therapy with plasma-derived von Willebrand factor-factor VIII concentrates represents the safe mainstay of treatment of all patients, particularly those not responding to desmopressin or requiring a sustained hemostatic correction because of major surgery or bleeding. A significant patient bleeding history correlates with increased bleeding risk and should be considered in tailoring the optimal antihemorrhagic prophylaxis in the individual patient.