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Sample records for meister stefan werner

  1. In Memoriam Werner Callebaut.

    PubMed

    Boniolo, Giovanni

    2015-12-01

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

  2. Correlations in Werner States

    NASA Astrophysics Data System (ADS)

    Luo, Shun-Long; Li, Nan

    2008-02-01

    Werner states are paradigmatic examples of quantum states and play an innovative role in quantum information theory. In investigating the correlating capability of Werner states, we find the curious phenomenon that quantum correlations, as quantified by the entanglement of formation, may exceed the total correlations, as measured by the quantum mutual information. Consequently, though the entanglement of formation is so widely used in quantifying entanglement, it cannot be interpreted as a consistent measure of quantum correlations per se if we accept the folklore that total correlations are measured (or rather upper bounded) by the quantum mutual information.

  3. Wilhelm Meister's Apprenticeship: The Paradox of a Liberating Pedagogy.

    ERIC Educational Resources Information Center

    Roosevelt, Jinx

    1980-01-01

    In analyzing the educational sequences of Goethe's novel, "Wilhelm Meister's Apprenticeship," the author suggests ways that this literary genre, the bildungsroman, which portrays an individual's development through a series of educational encounters, can provide teacher education students with material for studying the riddlelike quality of the…

  4. Stefan Meyer: Pioneer of Radioactivity

    NASA Astrophysics Data System (ADS)

    Reiter, Wolfgang L.

    2001-03-01

    Stefan Meyer was one of the pioneers in radioactivity research and director of the Vienna Radium Institute, the first institution in the world devoted exclusively to radioactivity. I give here a biographical sketch of Meyer and of some of his colleagues and an overview of the research activities at the Radium Institute.

  5. Stefan-Boltzmann Law for Massive Photons

    NASA Astrophysics Data System (ADS)

    Moreira, E. S.; Ribeiro, T. G.

    2016-08-01

    This paper generalizes the Stefan-Boltzmann law to include massive photons. A crucial ingredient to obtain the correct formula for the radiance is to realize that a massive photon does not travel at the speed of (massless) light. It follows that, contrary to what could be expected, the radiance is not proportional to the energy density times the speed of light.

  6. Werner Heisenberg (1901-1976)

    NASA Astrophysics Data System (ADS)

    Yang, Chen Ning

    2013-05-01

    Werner Heisenberg was one of the greatest physicists of all times. When he started out as a young research worker, the world of physics was in a very confused and frustrating state, which Abraham Pais has described1 as: It was the spring of hope, it was the winter of despair using Charles Dickens' words in A Tale of Two Cities. People were playing a guessing game: There were from time to time great triumphs in proposing, through sheer intuition, make-shift schemes that amazingly explained some regularities in spectral physics, leading to joy. But invariably such successes would be followed by further work which reveal the inconsistency or inadequacy of the new scheme, leading to despair...

  7. Linkage disequilibrium, haplotype analysis and Werner`s syndrome

    SciTech Connect

    Wijsman, E.M.; Goddard, K.A.B.; Martin, G.M.

    1994-09-01

    Werner`s syndrome (WS) is a rare, autosomal, recessive disorder of premature aging. Although the underlying defect is unknown, the gene for the disorder, WRN, has been mapped to the 8p11.1-21.1 region. We have assembled a sample of 30 Japanese and 24 non-Japanese (primary Caucasian) WS patients, as well as a control sample from each population. 25 of the Japanese patients and 10 of the Caucasian patients are from consanguineous marriages. We recently presented evidence from these families which places WRN in the 10.2 cM interval between D8S87 and D8S137. However, because WS is so rare and because many patients are from consanguineous marriages, fine localization of the gene by traditional meiotic mapping methods is unlikely to succeed. The existence of linkage disequilibrium is now recognized as a key piece of evidence in defining a small region (typically under 1-2 cM) containing a gene of interest. Thus an alternative approach for refining the location of WRN may be to identify linked markers which are in linkage disequilibrium with the disease. We recently suggested that WRN may be close to D8S339 and GSR in the above interval because of the presence of statistically significant evidence of linkage disequilibrium in the Japanese sample. In addition, there was evidence in both populations that a limited number of haplotypes was associated with the disease. Here we report an extension of this study to include a number of additional markers. We present additional evidence that there is linkage disequilibrium between many of these markers and WRN in both the Japanese and Caucasian samples. In addition, the additional markers do not markedly subdivide the disease haplotypes defined by D8S339 and GSR, while at the same time they introduce substantial numbers of new haplotypes into the control populations. These results suggest that the haplotypes associated with WS may be used to further define the limits of WRN.

  8. A Stefan problem on an evolving surface

    PubMed Central

    Alphonse, Amal; Elliott, Charles M.

    2015-01-01

    We formulate a Stefan problem on an evolving hypersurface and study the well posedness of weak solutions given L1 data. To do this, we first develop function spaces and results to handle equations on evolving surfaces in order to give a natural treatment of the problem. Then, we consider the existence of solutions for data; this is done by regularization of the nonlinearity. The regularized problem is solved by a fixed point theorem and then uniform estimates are obtained in order to pass to the limit. By using a duality method, we show continuous dependence, which allows us to extend the results to L1 data. PMID:26261364

  9. Eggshell conductance--Fick's or Stefan's law?

    PubMed

    Simkiss, K

    1986-08-01

    The diffusion of gases through the avian eggshell has usually been interpreted as an example of Fick's law, and this appears to be the best explanation for gas exchange through narrow long pores. Many eggshells, however, contain more elaborate pores, of which the funnel-shaped type is the most common. It is suggested that most of the resistance to diffusion through these types of pores is best explained by Stefan's law of diffusion through apertures. The implications of this theory to the understanding of pore functions are discussed.

  10. Werner coordination chemistry and neurodegeneration.

    PubMed

    Telpoukhovskaia, Maria A; Orvig, Chris

    2013-02-21

    Neurodegenerative diseases are capturing the world's attention as being the next set of diseases we must tackle collectively. Not only are the patients experiencing gradual cognitive and physical decline in most cases, but these diseases are fatal with no prevention currently available. As these diseases are progressive, providing care and symptom treatment for the ageing population is becoming both a medical and a financial challenge. This review discusses how Werner coordination chemistry plays a role in three diseases - those of Alzheimer's, Parkinson's, and prions. Metal ions are considered to be involved in these diseases in part via their propensity to cause toxic aggregation of proteins. First, the coordination of metal ions, with emphasis on copper(II), to metalloproteins that are hallmarks of these diseases - amyloid β, α-synuclein, and prion, respectively - will be discussed. We will present the current understanding of the metal coordination environments created by the amino acids of these proteins, as well as metal binding affinity. Second, a diverse set of examples of rationally designed metal chelators to outcompete this deleterious binding will be examined based on coordination mode and affinity toward bio-relevant metal ions. Overall, this review will give a general overview of protein and metal chelator coordination environments in neurodegenerative diseases.

  11. Werner deconvolution for variable altitude aeromagnetic data

    SciTech Connect

    Ostrowski, J.S. ); Pilkington, M.; Teskey, D.J. )

    1993-10-01

    The standard Werner deconvolution method is extended to include the effects of variable sensor altitude but this leads to a deconvolution algorithm that is unstable for slowly changing flight height. By expressing the sensor altitude as a linear function of horizontal position (within a specified window), the authors show that the numerical instability can be avoided. The subsequent selection and averaging of the raw solutions is controlled by three parameters that can be adjusted to specific survey data characteristics. Results for an aeromagnetic survey over Vancouver Island, British Columbia show that, in comparison with the variable altitude approach, the standard Werner method produces unacceptable errors when applied to variable altitude data.

  12. [The suicide problem in Stefan Zweig's works].

    PubMed

    Haenel, T

    1981-01-01

    The life of the Vienna-born writer Stefan Zweig, whose centenary will be on November 28th, 1981, is portrayed in the light of some external data. His works - mainly novellas - in which the theme of suicide plays a central role, are briefly presented, and his preference for describing psychological borderline and extreme states is stressed. One of his first poems and his last one - more than forty years lie between them - are discussed with reference to his depression and suicidal tendencies. Zweig, who at least since the First World war had been periodically suffering from depressions, was looked after and in a sense also treated by his first wife Friderike von Winternitz, until he had to leave his home in Salzburg in 1935. In 1939, he divorced from his wife and married his sickly secretary, Lotte Altmann, who suffered from asthma and depression. After prolonged stays in England, North and South America he settled in Petropolis near Rio de Janeiro in Brasil, where he spent the last months of his life. Zweig was the second son of a dominating, self-willed mother and a dignified, almost "motherly" father. He felt his childhood to have been constricted and hemmed in. His narcissism, which has played an essential role in relation to his suicide, has its roots in his childhood. Direct as well as indirect hints at suicide were not lacking during the last two years of Zweig's life, which were increasingly filled with depression and anxiety. The preface to his autobiography "The World of Yesterday" may be interpreted as an indirect announcement of suicide. On February 22nd, 1942, Zweig committed suicide together with his second wife in Petropolis.

  13. Immortalization of Werner syndrome and progeria fibroblasts

    SciTech Connect

    Saito, H.; Moses, R.E. )

    1991-02-01

    Human fibroblast cells from two different progeroid syndromes, Werner syndrome (WS) and progeria, were established as immortalized cell lines by transfection with plasmid DNA containing the SV40 early region. The lineage of each immortalized cell line was confirmed by VNTR analysis. Each of the immortalized cell lines maintained its original phenotype of slow growth. DNA repair ability of these cells was also studied by measuring sensitivity to killing by uv or the DNA-damaging drugs methyl methansulfonate, bleomycin, and cis-dichlorodiamine platinum. The results showed that both WS and progeria cells have normal sensitivity to these agents.

  14. Optical activity and Alfred Werner's coordination chemistry.

    PubMed

    Ernst, Karl-Heinz; Berke, Heinz

    2011-03-01

    It is widely accepted, that Pasteur's seminal discovery of the opposite optical activity of ammonium sodium tartrate enantiomorphs in solution gave the spark to organic stereochemistry and led to the development of the tetrahedron model by van't Hoff and Le Bel. The proof that chirality is inherently connected to octahedral coordination chemistry fostered greatly Werner's spatial views of metal complexes and his coordination theory. The actual proof of principle was established via separation of diastereomeric camphor sulfonate salts of racemic metal complexes. PMID:20928897

  15. 100 Years Werner Heisenberg: Works and Impact

    NASA Astrophysics Data System (ADS)

    Papenfuß, Dietrich; Lüst, Dieter; Schleich, Wolfgang P.

    2003-09-01

    Over 40 renowned scientists from all around the world discuss the work and influence of Werner Heisenberg. The papers result from the symposium held by the Alexander von Humboldt-Stiftung on the occasion of the 100th anniversary of Heisenberg's birth, one of the most important physicists of the 20th century and cofounder of modern-day quantum mechanics. Taking atomic and laser physics as their starting point, the scientists illustrate the impact of Heisenberg's theories on astroparticle physics, high-energy physics and string theory right up to processing quantum information.

  16. Quantum nondemolition measurement of the Werner state

    SciTech Connect

    Jin Jiasen; Yu Changshui; Pei Pei; Song Heshan

    2010-10-15

    We propose a theoretical scheme of quantum nondemolition measurement of two-qubit Werner state. We discuss our scheme with the two qubits restricted in a local place and then extend the scheme to the case in which two qubits are separated. We also consider the experimental realization of our scheme based on cavity quantum electrodynamics. It is very interesting that our scheme is robust against the dissipative effects introduced by the probe process. We also give a brief interpretation of our scheme finally.

  17. Determining Planetary Temperatures with the Stefan-Boltzmann Law

    ERIC Educational Resources Information Center

    LoPresto, Michael C.; Hagoort, Nichole

    2011-01-01

    What follows is a description of several activities involving the Stefan-Boltzmann radiation law that can provide laboratory experience beyond what is normally found in traditional introductory thermodynamics experiments on thermal expansion, specific heat, and heats of transformation. The activities also provide more extensive coverage of and…

  18. Chronic leg ulcers in Werner's syndrome.

    PubMed

    Yeong, E K; Yang, C C

    2004-01-01

    We report two siblings suffered from Werner's syndrome, which is a rare premature aging disorder caused by genetic mutations. They developed premature aging during adolescence with loss and graying of hair, short stature, baldness, atrophic skin, thin extremities, flat feet, 'bird' face and cataracts. Multiple chronic ulcers were noted over the feet in both patients. Healing was prolonged because of atrophic subcutaneous tissue, poor perfusion, impaired fibroblast activity and the loss of normal foot architecture. Treatment of the ulcers was challenging, as flap options were limited over the lower third of the leg and skin grafting was not easy as there was a lack of healthy granulations. However, we have successfully closed the ulcers with Integra artificial skin and ultra-thin split thickness skin grafting with the scalp as donor site. The main purpose of this paper is to alert physicians to this syndrome when treatments are being planned for patients with chronic leg ulcers.

  19. Werner's syndrome: incidental finding during pregnancy

    PubMed Central

    Hurtarte Sandoval, A R; Penate Dardón, J D; Flores Robles, B J; Porres, S

    2013-01-01

    Werner's syndrome (WS) is a rare autosomal recessive disorder, characterised by skin changes prematurely during adolescence. An unusual case of WS was found in a 27-year-old pregnant woman who presented to the hospital with a history of uncontrolled hypertension at 32 weeks of gestation. All clinical features corresponding to WS (early aging of skin, hair loss, blurred vision and diabetes type 2) appeared to match with the prospective diagnosis, which was confirmed later with genetic testing. The pregnancy became complicated due to oligohydramnios and therefore a caesarean section was carried out in order to preserve the fetus. Despite all implemented efforts, the patient died intraoperative as a result of cardiac arrest and its complications. Successfully, the newborn survived and it was further investigated to exclude this condition. PMID:24302663

  20. Reflections on My Werner H. Kirsten Student Internship | Poster

    Cancer.gov

    By Nathalie Walker, Guest Writer Editor’s note: This article represents one student’s perspective on her experiences as a Werner H. Kirsten student intern. Failure isn’t just a possibility, it is a certainty; yet failure is what leads you to success. Above all else, that is what I will retain from my experience in the Werner H. Kirsten Student Intern Program (WHK SIP).

  1. [Werner Villinger and National Socialist medical crimes].

    PubMed

    Schmuhl, H W

    2002-11-01

    The biography of the psychiatrist and neurologist Werner Villinger reflects the ambivalence of the history of German psychiatry during the first half of the twentieth century. Politically committed to the national conservatives, he was attracted by many elements of National Socialist (Nazi) ideology. Still, he joined the party rather late and reluctantly. Villinger was a eugenist by firm conviction. While he still argued against hasty legal regulation of eugenic sterilisations in the Weimar Republic, he strongly moved for translating the law on preventing hereditarily ill progeny into reality in the institution of von Bodelschwingh in Bethel. Since 1941, Villinger, who had become a professor for psychiatry and neurology in Breslau in the meantime, acted as an expert in the framework of the National Socialist "euthanasia" programme. At the same time, however, he supported the quiet diplomacy of Rev. von Bodelschwingh in his attempt to terminate the mass murder. Villinger was also involved in criminal experiments with human beings. After 1945, he successfully continued his career in the Federal Republic of Germany. He never confronted his past during the Third Reich. PMID:12430048

  2. [Werner Villinger and National Socialist medical crimes].

    PubMed

    Schmuhl, H W

    2002-11-01

    The biography of the psychiatrist and neurologist Werner Villinger reflects the ambivalence of the history of German psychiatry during the first half of the twentieth century. Politically committed to the national conservatives, he was attracted by many elements of National Socialist (Nazi) ideology. Still, he joined the party rather late and reluctantly. Villinger was a eugenist by firm conviction. While he still argued against hasty legal regulation of eugenic sterilisations in the Weimar Republic, he strongly moved for translating the law on preventing hereditarily ill progeny into reality in the institution of von Bodelschwingh in Bethel. Since 1941, Villinger, who had become a professor for psychiatry and neurology in Breslau in the meantime, acted as an expert in the framework of the National Socialist "euthanasia" programme. At the same time, however, he supported the quiet diplomacy of Rev. von Bodelschwingh in his attempt to terminate the mass murder. Villinger was also involved in criminal experiments with human beings. After 1945, he successfully continued his career in the Federal Republic of Germany. He never confronted his past during the Third Reich.

  3. [Rudolf Stefan Weigl--scientist and human being].

    PubMed

    Tylewska-Wierzbanowska, S; Zielińska, Zofia; Chmielowski, Jerzy

    2003-01-01

    Rudolf Stefan Weigl died in 1957, 45 years ago. This year we are celebrating 120 anniversary of his birthday. He was a great Polish scientist who led research on Rickettsia prowazeki and epidemic typhus. R. Weigl developed a method of R. prowazeki culture in louse gut and elaborated the technology of epidemic typhus vaccine production. He and his co-workers introduced first vaccination of medical staff, people from endemic area in Poland and missionaries working in Asia. He was an international authority on prophylactics and control of rickettsial epidemic typhus.

  4. Single-phase Stefan problem in selectively absorbing medium

    NASA Astrophysics Data System (ADS)

    Sleptsov, S. D.; Rubtsov, N. A.; Savvinova, N. A.

    2016-01-01

    The thermal state of a translucent selectively absorbing medium was studied by the methods of numerical simulation at different values of the optical properties of boundaries and heat transfer from the left surface in approximation of one-phase Stefan problem. The temperature fields and densities of resultant radiation fluxes as well as the thermal state of the left boundary and dynamics of layer reduction in the melting process were analyzed. The processes of phase transition in a flat layer of selective and gray absorbing media and emitting media were compared, and their fundamental differences were shown.

  5. Diverse dealings of the Werner helicase/nuclease.

    PubMed

    Cheng, Wen-Hsing; Bohr, Vilhelm A

    2003-08-06

    The human Werner syndrome is a model for the process of aging. The protein that is mutated in Werner syndrome, WRN, exhibits three catalytic activities: a 3'-to-5' helicase, a 3'-to-5' exonuclease, and an adenosine triphosphatase activity. WRN interacts with a variety of proteins and has been implicated in many aspects of DNA metabolism. A recent paper by Chen et al. published in the August 2003 issue of Aging Cell sheds some light on the multifunctional nature of WRN. It suggests that WRN may be considered as a structural protein, providing a plausible conceptual basis for the many WRN protein-protein interactions.

  6. Correlations and Werner states in finite spin linear arrays

    NASA Astrophysics Data System (ADS)

    Wells, P. R.; Chaves, C. M.; d'Albuquerque e Castro, J.; Koiller, Belita

    2013-10-01

    Pairwise quantum correlations in the ground state of an N-spins antiferromagnetic Heisenberg chain are investigated. By varying the exchange coupling between two neighboring sites, it is possible to reversibly drive spins from entangled to disentangled states. For even N, the two-spin density matrix is written in the form of a Werner state, allowing identification of its single parameter with the usual spin-spin correlation function. The N = 4 chain is identified as a promising system for practical demonstrations of non-classical correlations and the realization of Werner states in familiar condensed matter systems. Fabrication and measurement ingredients are within current capabilities.

  7. Deficient DNA repair in the human progeroid disorder, Werner syndrome.

    PubMed

    Bohr, Vilhelm A

    2005-09-01

    The study of how DNA repair mechanisms change with aging is central to our understanding of the aging process. Here, I review the molecular functions of a key aging protein, Werner protein (WRN), which is deficient in the premature aging disorder, Werner syndrome (WS). This protein plays a significant role in DNA repair, particularly in base excision repair and in recombination. WRN may be a key regulatory factor in these processes and may also play a role in coordinating them. WRN belongs to the RecQ helicase family of proteins, often referred to as the guardians of the genome. These proteins appear to integrate with the more classic DNA repair pathways and proteins.

  8. [Werner Leibbrand as psychiatric opponent of National Socialism].

    PubMed

    Seidel, R

    2013-09-01

    The psychiatrist and medical historian Werner Leibbrand resigned from the Berlin Medical Association after the seizure of power in protest against the exclusion of Jewish colleagues and lost both the license to practice as well as his professional position in the public health service. After the end of the war the American military authorities appointed him as expert witness for the prosecution in the Nürnberg Doctors Trial. In addition to a biographical review, Leibbrand's resolute although still undisputed attitude as ethical expert in the trials will be roughly outlined.

  9. Bayesian Nash equilibria using extended Werner-like states

    NASA Astrophysics Data System (ADS)

    Alid-Vaccarezza, M.; Soto, M. E.

    2016-10-01

    We study quantum strategies in games of incomplete information using a formalism of game theory based on multi-sector probability matrix. We analyze an extension of the well-known game of Battle of Sexes using an extended Werner-like state focusing in how its mixedness and entanglement affect the Bayesian Nash payoffs of the player. It is shown that entanglement is needed to outperform classical payoffs but not all entangled states are useful due to the presence of mixedness. A threshold for the mixedness parameter and the minimum entanglement value were found.

  10. Bayesian Nash equilibria using extended Werner-like states

    NASA Astrophysics Data System (ADS)

    Alid-Vaccarezza, M.; Soto, M. E.

    2016-07-01

    We study quantum strategies in games of incomplete information using a formalism of game theory based on multi-sector probability matrix. We analyze an extension of the well-known game of Battle of Sexes using an extended Werner-like state focusing in how its mixedness and entanglement affect the Bayesian Nash payoffs of the player. It is shown that entanglement is needed to outperform classical payoffs but not all entangled states are useful due to the presence of mixedness. A threshold for the mixedness parameter and the minimum entanglement value were found.

  11. Some explicit solutions for a class of one-phase Stefan problems

    NASA Astrophysics Data System (ADS)

    Layeni, Olawanle P.; Johnson, Jesse V.

    2012-09-01

    Salva and Tarzia, [N.N. Salva, D.A. Tarzia, J. Math. Anal. Appl. 379 (2011) 240 - 244], gave explicit solutions of a similarity type for a class of free boundary problem for a semi-infinite material. In this paper, through an elementary approach and less stringent assumption on data, we obtain more general results than those given by their central result, and thereby construct explicit solutions for a wider class of Stefan problems with a type of variable heat flux boundary conditions. Further, explicit solutions of certain forced one-phase Stefan problems are given.

  12. Absence of premature senescence in Werner's syndrome keratinocytes.

    PubMed

    Ibrahim, Badr; Sheerin, Angela N; Jennert-Burston, Katrin; Bird, Joe L E; Massala, M V; Illsley, Matthew; James, S Elizabeth; Faragher, Richard G A

    2016-10-01

    Werner's syndrome (WS) is an autosomal recessive genetic disorder caused by loss of function mutation in wrn and is a useful model of premature in vivo ageing. Cellular senescence is a plausible causal mechanism of mammalian ageing and, at the cellular level, WS fibroblasts show premature senescence resulting from a combination of telomeric attrition and replication fork stalling. Over 90% of WS fibroblast cultures achieve <20 population doublings (PD) in vitro compared to wild type human fibroblast cultures. It has been proposed that some cell types, capable of proliferation, will fail to show a premature senescence phenotype in response to wrn mutations. To test this hypothesis, human dermal keratinocytes (derived from both WS and wild type patients) were cultured long term. WS Keratinocytes showed a replicative lifespan in excess of 100 population doublings but maintained functional growth arrest mechanisms based on p16 and p53. The karyotype of the cells was superficially normal and the cultures retained markers characteristic of keratinocyte holoclones (stem cells) including p63 expression and telomerase activity. Accordingly we conclude that, in contrast to WS fibroblasts, WS keratinocytes do not demonstrate slow growth rates or features of premature senescence. These findings suggest that the epidermis is among the tissue types that do not display symptoms of premature ageing caused by loss of function of wrn. This is in support that Werner's syndrome is a segmental progeroid syndrome. PMID:27492502

  13. Podolsky electromagnetism at finite temperature: Implications on the Stefan-Boltzmann law

    SciTech Connect

    Bonin, C. A.; Bufalo, R.; Pimentel, B. M.; Zambrano, G. E. R.

    2010-01-15

    In this work we study Podolsky electromagnetism in thermodynamic equilibrium. We show that a Podolsky mass-dependent modification to the Stefan-Boltzmann law is induced and we use experimental data to limit the possible values for this free parameter.

  14. Werner Brandt legacy to PIXE: Past and present perspectives

    NASA Astrophysics Data System (ADS)

    Lapicki, Gregory

    2014-01-01

    Inner-shell ionization cross sections used in Particle-Induced X-ray Elemental (PIXE) analyses are routinely calculated in the ECPSSR [W. Brandt, G. Lapicki, Phys. Rev. A 23 (1981) 1717-1729] theory and/or semiempirical formulas scaled to that theory. Thirty years after the passing of Werner Brandt, with recognition of his seminal contributions to other research on positron physics and stopping power problems, the work and articles that progressed into the ECPSSR theory for inner-shell ionization by protons and heavier ions are recalled as Brandt's past legacy to the PIXE community. Applications of the ECPSSR and its evolution into the ECUSAR [G. Lapicki, Nucl. Instr. Meth. B 189 (2002) 8-20] theory over the last three decades are reviewed with perspectives on Brandt's present legacy.

  15. Werner Heisenberg zum 100. Geburtstag: Pionier der Quantenmechanik

    NASA Astrophysics Data System (ADS)

    Jacobi, Manfred

    2001-11-01

    Werner Heisenberg war eine der prägendsten Gestalten der Physik des 20. Jahrhunderts. Zu seinen wichtigsten Verdiensten gehören die Grundlegung der Quantenmechanik, die Formulierung der Unschärferelationen sowie die Beteiligung an der Ausarbeitung der Kopenhagener Deutung der Quantenmechanik. Darüber hinaus lieferte er Arbeiten von fundamentalem Charakter zur Theorie des Atomkerns, zur kosmischen Strahlung und zur Quantenfeldtheorie. Während des Krieges war er an den Arbeiten des Uranvereins beteiligt, der die Möglichkeit einer Entwicklung von Kernwaffen untersuchte, jedoch über Vorarbeiten zur Reaktorphysik nicht hinauskam. Wegen dieser Tätigkeit wurde er bei Kriegsende für einige Monate in England interniert. Nach seiner Rückkehr widmete er sich vor allem dem Aufbau der Physik in Deutschland, die während der NS-Zeit nahezu ihrer gesamten Substanz beraubt worden war.

  16. Werner syndrome through the lens of tissue and tumour genomics

    PubMed Central

    Tokita, Mari; Kennedy, Scott R.; Risques, Rosa Ana; Chun, Stephen G.; Pritchard, Colin; Oshima, Junko; Liu, Yan; Bryant-Greenwood, Peter K.; Welcsh, Piri; Monnat, Raymond J.

    2016-01-01

    Werner syndrome (WS) is the canonical adult human progeroid (‘premature aging’) syndrome. Patients with this autosomal recessive Mendelian disorder display constitutional genomic instability and an elevated risk of important age-associated diseases including cancer. Remarkably few analyses of WS patient tissue and tumors have been performed to provide insight into WS disease pathogenesis or the high risk of neoplasia. We used autopsy tissue from four mutation-typed WS patients to characterize pathologic and genomic features of WS, and to determine genomic features of three neoplasms arising in two of these patients. The results of these analyses provide new information on WS pathology and genomics; provide a first genomic characterization of neoplasms arising in WS; and provide new histopathologic and genomic data to test several popular models of WS disease pathogenesis. PMID:27559010

  17. Werner syndrome through the lens of tissue and tumour genomics.

    PubMed

    Tokita, Mari; Kennedy, Scott R; Risques, Rosa Ana; Chun, Stephen G; Pritchard, Colin; Oshima, Junko; Liu, Yan; Bryant-Greenwood, Peter K; Welcsh, Piri; Monnat, Raymond J

    2016-01-01

    Werner syndrome (WS) is the canonical adult human progeroid ('premature aging') syndrome. Patients with this autosomal recessive Mendelian disorder display constitutional genomic instability and an elevated risk of important age-associated diseases including cancer. Remarkably few analyses of WS patient tissue and tumors have been performed to provide insight into WS disease pathogenesis or the high risk of neoplasia. We used autopsy tissue from four mutation-typed WS patients to characterize pathologic and genomic features of WS, and to determine genomic features of three neoplasms arising in two of these patients. The results of these analyses provide new information on WS pathology and genomics; provide a first genomic characterization of neoplasms arising in WS; and provide new histopathologic and genomic data to test several popular models of WS disease pathogenesis. PMID:27559010

  18. The clinical characteristics of Werner syndrome: molecular and biochemical diagnosis

    PubMed Central

    Muftuoglu, Meltem; Oshima, Junko; von Kobbe, Cayetano; Cheng, Wen-Hsing; Leistritz, Dru F.; Bohr, Vilhelm A.

    2015-01-01

    Werner syndrome (WS) is an adult onset segmental progeroid syndrome caused by mutations in the WRN gene. The WRN gene encodes a 180 kDa nuclear protein that possesses helicase and exonuclease activities. The absence of WRN protein leads to abnormalities in various DNA metabolic pathways such as DNA repair, replication and telomere maintenance. Individuals with WS generally develop normally until the third decade of life, when premature aging phenotypes and a series of age-related disorders begin to manifest. In Japan, where a founder effect has been described, the frequency of Werner heterozygotes appears to be as high as 1/180 in the general population. Due to the relatively non-specific nature of the symptoms and the lack of awareness of the condition, this disease may be under-diagnosed in other parts of the world. Genetic counseling of WS patients follows the path of other autosomal recessive disorders, with special attention needed for cancer surveillance in relatives. Molecular diagnosis of WS is made by nucleotide sequencing and, in some cases, protein analysis. It is also of potential interest to measure WRN activities in WS patients. More than 50 different disease-causing mutations in the WRN gene have been identified in WS patients from all over the world. All but one of these cases has mutations that result in the premature termination of the protein. Here we describe the clinical, molecular and biochemical characteristics of WS for use by medical professionals in a health care setting. Additional information is available through the International Registry of WS (http://www.wernersyndrome.org). PMID:18810497

  19. Quantum Discord and Entanglement of Quasi-Werner States Based on Bipartite Entangled Coherent States

    NASA Astrophysics Data System (ADS)

    Mishra, Manoj K.; Maurya, Ajay K.; Prakash, Hari

    2016-06-01

    Present work is an attempt to compare quantum discord and quantum entanglement of quasi-Werner states formed with the four bipartite entangled coherent states (ECS) used recently for quantum teleportation of a qubit encoded in superposed coherent state. Out of these, the quasi-Werner states based on maximally ECS due to its invariant nature under local operation is independent of measurement basis and mean photon numbers, while for quasi-Werner states based on non-maximally ECS, it depends upon measurement basis as well as on mean photon number. However, for large mean photon numbers since non-maximally ECS becomes almost maximally entangled therefore dependence of quantum discord for non-maximally ECS based quasi-Werner states on the measurement basis disappears.

  20. Werner Kolhörster (1887-1945): The German pioneer of cosmic ray physics

    NASA Astrophysics Data System (ADS)

    Fick, Dieter; Hoffmann, Dieter

    2014-01-01

    Werner Kolhörster belonged to the outstanding German scholars in cosmic ray and particle astrophysics, prior to World War II. But the wide fame of Victor F. Hess overshadows largely his merits nowadays.

  1. Lattice Boltzmann scheme for electrolytes by an extended Maxwell-Stefan approach.

    PubMed

    Zudrop, Jens; Roller, Sabine; Asinari, Pietro

    2014-05-01

    This paper presents an extended multicomponent lattice Boltzmann model for the simulation of electrolytes. It is derived by means of a finite discrete velocity model and its discretization. The model recovers momentum and mass transport according to the incompressible Navier-Stokes equation and Maxwell-Stefan formulation, respectively. It includes external driving forces (e.g., electric field) on diffusive and viscous scales, concentration-dependent Maxwell-Stefan diffusivities, and thermodynamic factors. The latter take into account nonideal diffusion behavior, which is essential as electrolytes involve charged species and therefore nonideal long and short-range interactions among the molecules of the species. Furthermore, we couple our scheme to a finite element method to include electrostatic interactions on the macroscopic level. Numerical experiments show the validity of the presented model. PMID:25353917

  2. Analytical solution of two-phase spherical Stefan problem by heat polynomials and integral error functions

    NASA Astrophysics Data System (ADS)

    Kharin, Stanislav N.; Sarsengeldin, Merey M.; Nouri, Hassan

    2016-08-01

    On the base of the Holm model, we represent two phase spherical Stefan problem and its analytical solution, which can serve as a mathematical model for diverse thermo-physical phenomena in electrical contacts. Suggested solution is obtained from integral error function and its properties which are represented in the form of series whose coefficients have to be determined. Convergence of solution series is proved.

  3. Solving ball lightning—A reply to Stefan and Massey (2008)

    NASA Astrophysics Data System (ADS)

    Coleman, Peter Francis

    2009-06-01

    Comments are made on the ball lightning paper of Stephan and Massey [Stefan, K.D., Massey, N., 2008. Burning molten metallic sphere: One class of ball lightning? Journal of Atmospheric and Solar-Terrestrial Physics 70, 1589-1596] that describes their [`]welding drop' theory. An alternative theory is offered based on combustion inside an atmospheric vortex. The [`]vortex fireball' hypothesis has good explanatory capability in regard to published ball lightning properties.

  4. Research in the field of nucleic acids performed in the "Stefan S. Nicolau" Institute of Virology.

    PubMed

    Popa, L M; Repanovici, R; Iliescu, R

    1985-01-01

    A review is made of the research in the field of nucleic acids performed in the "Stefan S. Nicolau" Institute of Virology. The results obtained as regards the infectivity of viral nucleic acids, the oncogenic capacity of nucleic acids extracted from tumors, the isolation, characterization, physicochemical and biological activity of viral and cellular nucleic acids, as well as some achievements in recombinant DNA technology, are briefly presented. PMID:3907119

  5. A comparison of Fick and Maxwell-Stefan diffusion formulations in PEMFC gas diffusion layers

    NASA Astrophysics Data System (ADS)

    Lindstrom, Michael; Wetton, Brian

    2016-04-01

    This paper explores the mathematical formulations of Fick and Maxwell-Stefan diffusion in the context of polymer electrolyte membrane fuel cell cathode gas diffusion layers. The simple Fick law with a diagonal diffusion matrix is an approximation of Maxwell-Stefan. Formulations of diffusion combined with mass-averaged Darcy flow are considered for three component gases. For this application, the formulations can be compared computationally in a simple, one dimensional setting. Despite the models' seemingly different structure, it is observed that the predictions of the formulations are very similar on the cathode when air is used as oxidant. The two formulations give quite different results when the Nitrogen in the air oxidant is replaced by helium (this is often done as a diagnostic for fuel cells designs). The two formulations also give quite different results for the anode with a dilute Hydrogen stream. These results give direction to when Maxwell-Stefan diffusion, which is more complicated to implement computationally in many codes, should be used in fuel cell simulations.

  6. Leg ulcer in Werner syndrome (adult progeria): a case report.

    PubMed

    Fumo, Giuseppe; Pau, Monica; Patta, Federico; Aste, Nicola; Atzori, Laura

    2013-01-01

    Werner syndrome (WS; MIM#277700) or adult progeria, is a rare disease, associated with mutations of a single gene (RECQL2 or WRN), located on chromosome 8 (8p12). It codes a DNA-helicase, whose defects cause genomic instability. The highest incidences are reported in Japan and Sardinia (Italy). On this major island of the Mediterranean Basin, the WS cases have been observed in the northern areas. The authors describe the apparently first case reported in southern Sardinia, a 51-year-old woman, who was born in and resides in the province of Cagliari. She presented with a 9-year history of an intractable leg ulcer and other characteristic symptoms, including "bird-like" face, high-pitched voice, premature greying, short stature, abdominal obesity in contrast with thin body type, scleroderma-like legs, decreased muscle mass, diabetes, atherosclerosis, and premature menopause. A specialized genetic Institute of Research (IRCCS-IDI, Rome) confirmed the clinical diagnosis. There is no cure or specific treatment and patients must be periodically screened for an increased risk of cardiovascular and cerebrovascular disease and malignancies. Among the many findings, leg ulcers significantly affect the patient's quality of life. This problem may send the patient to the dermatologist, who finally suspects the diagnosis. Poor response to medical treatment may require aggressive repeated surgery, with poor or temporary results.

  7. Liver aging and pseudocapillarization in a Werner syndrome mouse model.

    PubMed

    Cogger, Victoria C; Svistounov, Dmitri; Warren, Alessandra; Zykova, Svetlana; Melvin, Richard G; Solon-Biet, Samantha M; O'Reilly, Jennifer N; McMahon, Aisling C; Ballard, J William O; De Cabo, Rafa; Le Couteur, David G; Lebel, Michel

    2014-09-01

    Werner syndrome is a progeric syndrome characterized by premature atherosclerosis, diabetes, cancer, and death in humans. The knockout mouse model created by deletion of the RecQ helicase domain of the mouse Wrn homologue gene (Wrn(∆hel/∆hel)) is of great interest because it develops atherosclerosis and hypertriglyceridemia, conditions associated with aging liver and sinusoidal changes. Here, we show that Wrn(∆hel/∆hel) mice exhibit increased extracellular matrix, defenestration, decreased fenestration diameter, and changes in markers of liver sinusoidal endothelial cell inflammation, consistent with age-related pseudocapilliarization. In addition, hepatocytes are larger, have increased lipofuscin deposition, more frequent nuclear morphological anomalies, decreased mitochondria number, and increased mitochondrial diameter compared to wild-type mice. The Wrn(∆hel/∆hel) mice also have altered mitochondrial function and altered nuclei. Microarray data revealed that the Wrn(∆hel/∆hel) genotype does not affect the expression of many genes within the isolated hepatocytes or liver sinusoidal endothelial cells. This study reveals that Wrn(∆hel/∆hel) mice have accelerated typical age-related liver changes including pseudocapillarization. This confirms that pseudocapillarization of the liver sinusoid is a consistent feature of various aging models. Moreover, it implies that DNA repair may be implicated in normal aging changes in the liver.

  8. [The birth of acknowledgement: Michel Foucault and Werner Leibbrand].

    PubMed

    Mildenberger, Florian

    2006-01-01

    In 1964, Werner Leibbrand (1896-1974) was the first German medical historian to present, in Sudhoffs Archiv, a review of the work of Michel Foucault (1926-1984). This paper examines some of the reasons leading to the fact that Leibbrand's own generation refused to acknowledge the importance of Foucault's ideas, while, later on, younger German medical historians, although impressed with Foucault's writings, failed to acknowledge, first, the close relationship between Leibbrand's and Foucault's world views, and, second, Leibbrand's attempts at introducing Foucault to German medical historians. Leibbrand with his Jewish wife had survived the Nazi period partly in hiding. His attempts at clearing post-war German psychiatry and medical historiography of NS-sympathizers isolated him among his colleagues, many of whom had begun their career during the Third Reich. Leibbrand enjoyed the support by the Swiss medical historian and avowed Communist Erwin Ackerknecht (1906-1988), but later turned against him, possibly because Acknerknecht had called Leibbrand's writings "unscientific". Leibbrand was unable to overcome his antagonisms with his contemporaries. At the same time, opposition to Ackerknecht made him appear a respresentative of the past in the eyes of the younger generation. Thus, when Foucault was accepted by the latter, they were not prepared to examine the work of Leibbrand and realize how close some of the ideas developed by Leibbrand and Foucault had been.

  9. Werner helicase polymorphism is not associated with Alzheimer's disease.

    PubMed

    Payão, Spencer Luiz Marques; de Labio, Roger Willian; Gatti, Luciano Lobo; Rigolin, Valdeci O S; Bertolucci, Paulo H F; Smith, Marília de A C

    2004-12-01

    Alzheimer disease (AD) is the most common neurodegenerative disorder in the elderly and is also considered a progeroid genetic syndrome. The etiology of AD is complex and the mechanisms underlying its pathophysiology remains to be clarified. Werner syndrome (WS) is a rare autosomal recessive disorder characterized as a segmental progeroid syndrome. The gene (WRN) was recently identified. Its product acts as a DNA helicase and exonuclease. This study investigates the association of AD with the WRN 1367 polymorphisms in samples of 67 DA patients, 56 elderly healthy and 66 young healthy controls. DNA was isolated from blood cells, amplified by PCR and digested with PmaCI. We observed that the genotype distributions of WRN 1367 variants were within Hardy-Weinberg equilibrium in all subject samples. Furthermore, chi-square test comparison for genotype distributions and allele frequencies did not reveal any significant difference among the three groups of subjects (P>0.05). These results support the idea that these variants are not involved as a risk factor for developing AD.

  10. Homozygosity mapping of the Werner syndrome locus (WRN)

    SciTech Connect

    Nakura, J.; Miki, T.; Kamino, K.

    1994-10-01

    Werner syndrome (WS) is an autosomal recessive disorder characterized by the early onset of several age-related diseases. The locus for this disease was recently mapped to 8p12. We studied 27 WS kindreds of mixed ethnic origins, 26 of which were consanguineous. In 24 of these families, the affected subject was given the diagnosis of {open_quotes}definite{close_quotes} WS and affected subjects in the remaining 3 pedigrees were given the diagnosis of {open_quotes}probable{close_quotes} WS. Affected subjects from each kindred were genotyped for 13 short tandem repeat polymorphic sites. Two-point linkage analysis yielded significant evidence for linkage to D8S137, D8S339, D8S87, PLAT, D8S165, and D8S166. The locus yielding a maximum lod score at the smallest recombination fraction was D8S339, suggesting that this marker is the closest to the WS gene (WRN locus) of those tested. D8S339 gave significant lod scores (Z{sub max}{>=}3.0) for both Japanese and non-Japanese (mostly Caucasian) families, demonstrating that a single locus is responsible for WS in both groups. Multipoint analysis of these markers yielded a maximum lod score of 17.05 at a distance of approximately 0.6 cM from D8S339. The combined evidence from 2-point analysis, multipoint analysis, and analysis of regions of homozygosity in subjects from inbred pedigrees indicates that the WRN locus is between D8S131 and D8S87, in an 8.3-cM interval containing D8S339. 32 refs., 1 fig., 5 tabs.

  11. Global stability of steady states in the classical Stefan problem for general boundary shapes

    PubMed Central

    Hadžić, Mahir; Shkoller, Steve

    2015-01-01

    The classical one-phase Stefan problem (without surface tension) allows for a continuum of steady-state solutions, given by an arbitrary (but sufficiently smooth) domain together with zero temperature. We prove global-in-time stability of such steady states, assuming a sufficient degree of smoothness on the initial domain, but without any a priori restriction on the convexity properties of the initial shape. This is an extension of our previous result (Hadžić & Shkoller 2014 Commun. Pure Appl. Math. 68, 689–757 (doi:10.1002/cpa.21522)) in which we studied nearly spherical shapes. PMID:26261359

  12. Alfred Werner's role in the mid-20th century flourishing of American inorganic chemistry.

    PubMed

    Labinger, Jay A

    2014-01-01

    The development of organic and physical chemistry as specialist fields, during the middle and end of the 19th century respectively, left inorganic behind as a decidedly less highly regarded subfield of chemistry. Despite Alfred Werner's groundbreaking studies of coordination chemistry in the early 20th century, that inferior status remained in place - particularly in the US - until the 1950s, when the beginnings of a resurgence that eventually restored its parity with the other subfields can be clearly observed. This paper explores the extent to which Werner's heritage - both direct, in the form of academic descendants, and indirect - contributed to those advances. PMID:24983802

  13. [Developmental conditions of medicine and spiritual culture at the time of grand Prince Stefan Nemanja].

    PubMed

    Ilić-Tasić, Slobodanka; Ravinić, Dragan; Pantović, Mihailo; Bojanić, Vladmila; Pavlović, Budimir

    2012-01-01

    Medieval medicine and pharmacy were the subjects of numerous researches. The enviable level of health culture and social care of the diseased and debilitated people of the Serbian medieval state was far advanced for the time. However, there are scarce written records of the conditions. The purpose of this paper is to point out the conditions which enabled the foundation of the first Serbian hospitals, development of scientific medicine and spiritual culture in medieval Serbian lands. Favourable conditions for the development of medieval medicine are linked with the arrival of the Nemanjić dynasty to the throne of the Serbian medieval state, i.e. Stefan Nemanja, and later with the life and work of his son Prince Rastko Nemanjić - Saint Sava. The wide field of activity of the Grand Prince Stefan Nemanja included the creation of stable and independent state ("the unifier of all Serbian lands") with a significant and shrewd political activity (vassal to Byzantine Emperor Manuel Comnenus, participation in great alliances against Byzantium), building of churches, defender of the Orthodox Christianity, foundation of the first Serbian hospital outside of borders of Serbian state in Hilandar monastery, social care about people and cultivating literary activity. PMID:22650117

  14. A particulate pulse-release system and mathematical description with the Maxwell-Stefan theory.

    PubMed

    Hartman Kok, P J; Vonk, P; Kossen, N W

    2000-05-15

    In this contribution both the development of a multi-particulate delayed release system with release properties dependent on the swelling of an UV crosslinked coating and a mathematical model to describe its release properties are presented. The formulation consists of a water-soluble core coated with a copolymer of methacrylic acid and ethyl acrylate. Incorporating a network of crosslinked pentaerythritol triacrylate decreases the water-solubility of the coating. After immersing the formulation in water the coating will take up water and subsequently swell in such a degree that the diffusion coefficient of water in the coating will increase. This makes the coating permeable to the dissolved components present in the core. The swelling kinetics of the coating are such that the formulation has a pulse-release profile, i.e. a fast release of the contents is obtained after a pre-determined lag-time. Both the coating thickness and the duration of the UV crosslinking time can be used to adjust the lag-time. The experimental results are used to estimate the Maxwell-Stefan diffusion coefficients of water in the coating. The relation between the Maxwell-Stefan diffusion coefficient and the mole fraction of water in the coating differs from results found in the literature. However, the prediction of the release time based on the presented model is in good agreement with the experimental findings.

  15. Super-resolved fluorescence microscopy: Nobel Prize in Chemistry 2014 for Eric Betzig, Stefan Hell, and William E. Moerner.

    PubMed

    Möckl, Leonhard; Lamb, Don C; Bräuchle, Christoph

    2014-12-15

    A big honor for small objects: The Nobel Prize in Chemistry 2014 was jointly awarded to Eric Betzig, Stefan Hell, and William E. Moerner "for the development of super-resolved fluorescence microscopy". This Highlight describes how the field of super-resolution microscopy developed from the first detection of a single molecule in 1989 to the sophisticated techniques of today.

  16. [Intellectual exchange between Germany and Latin America: an interview with Stefan Rinke].

    PubMed

    Rinke, Stefan; da Silva, André Felipe Cândido; Junghans, Miriam; Cavalcanti, Juliana Manzoni; de Muñoz, Pedro Felipe Neves

    2014-01-01

    Current and former students of the Casa de Oswaldo Cruz/Fiocruz interviewed German historian Stefan Rinke, of the Freie Universität Berlin, who specializes in examining the historical development of Latin America as it fits into the international context. Rinke's work uses dimensions such as economic and diplomatic relations, migratory flows, and ethnic conflict as tools in his analyses of the networks of interdependence that have tied Latin America to Europe and the USA. His lens goes beyond the Latin American continent to approach globalization as a historical process, with national and regional contexts placed within a general framework. In this interview, Rinke talks about his academic career, global and transnational history, and joint projects between Germany and Latin America.

  17. Exact solution of two phase spherical Stefan problem with two free boundaries

    NASA Astrophysics Data System (ADS)

    Kavokin, Alexey A.; Nauryz, Targyn; Bizhigitova, Nazerke T.

    2016-08-01

    Solution of the heat equation in a spherical domain with two free boundaries (two-phase Stefan problem) when one of the subdomains degenerates at the initial time is considered. The use of conventional finite-difference methods in these cases is not expedient because of the degenerate domain. The solution is found in the form of combination of Integral Error functions series, [M. Sarsengeldin, and S. Kharin, Filomat, (2016), (in Press)] and then recurrent solvability of nonlinear algebraic equations for determining the coefficients of the series is proved. Such problems are of practical interest for the simulation of laser material processing as well for the modeling of thermal effects of electric arc that ignites during the opening of electric contacts [S. N. Kharin, and M. Sarsengeldin, Influence of contact materials on phenomena in a short electrical arc, in Key Engineering Materials, Trans tech publications, Islamabad, Pakistan, 2012, pp. 321-329].

  18. WRN mutations in Werner syndrome patients: genomic rearrangements, unusual intronic mutations and ethnic-specific alterations

    PubMed Central

    Friedrich, Katrin; Lee, Lin; Leistritz, Dru F.; Nürnberg, Gudrun; Saha, Bidisha; Hisama, Fuki M.; Eyman, Daniel K.; Lessel, Davor; Nürnberg, Peter; Li, Chumei; Garcia-F-Villalta, María J.; Kets, Carolien M.; Schmidtke, Joerg; Cruz, Vítor Tedim; Van den Akker, Peter C.; Boak, Joseph; Peter, Dincy; Compoginis, Goli; Cefle, Kivanc; Ozturk, Sukru; López, Norberto; Wessel, Theda; Poot, Martin; Ippel, P. F.; Groff-Kellermann, Birgit; Hoehn, Holger; Martin, George M.; Kubisch, Christian; Oshima, Junko

    2015-01-01

    Werner syndrome (WS) is an autosomal recessive segmental progeroid syndrome caused by null mutations at the WRN locus, which codes for a member of the RecQ family of DNA helicases. Since 1988, the International Registry of Werner syndrome had enrolled 130 molecularly confirmed WS cases from among 110 worldwide pedigrees. We now report 18 new mutations, including two genomic rearrangements, a deep intronic mutation resulting in a novel exon, a splice consensus mutation leading to utilization of the nearby splice site, and two rare missense mutations. We also review evidence for founder mutations among various ethnic/geographic groups. Founder WRN mutations had been previously reported in Japan and Northern Sardinia. Our Registry now suggests characteristic mutations originated in Morocco, Turkey, The Netherlands and elsewhere. PMID:20443122

  19. 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.

  20. Simultaneous removal of acetone and ethanol from aqueous solutions by membrane distillation: prediction using the Fick's and the exact and approximate Stefan-Maxwell relations

    NASA Astrophysics Data System (ADS)

    Banat, F. A.; Al-Rub, F. A.; Shannag, M.

    The simultaneous removal of dilute acetone and ethanol from aqueous solutions by air gap membrane distillation is theoretically investigated. A combined heat and mass transfer model that includes temperature and concentration polarization effects as well as temperature and concentration variation along the module length is employed to predict the flux and selectivity of acetone and ethanol under the relevant process operating conditions. Three mass transfer solutions are considered in the model, namely; the exact Stefan-Maxwell (S-M), the approximate Stefan-Maxwell and the Fickian binary solution. Although, qualitatively, the three solutions exhibit the same trends, quantitatively some differences exist between the Fickian-based solution on one hand and the Stefan-Maxwell solutions on the other hand. The exact and approximate solutions of the Stefan-Maxwell equation showed similar capability in predicting the process performance under all process conditions. Predictions showed that acetone selectivity and flux were strongly dependent on feed conditions and air gap width.

  1. Investigations in the field of recombinant DNA technology performed in the "Stefan S. Nicolau" Institute of Virology.

    PubMed

    Popa, L M; Repanovici, R; Iliescu, R

    1984-01-01

    A brief review is provided of the investigations in the field of recombinant DNA technology started in 1979 in the Central Laboratory for Nucleic Acids within the "Stefan S. Nicolau" Institute of Virology. The research efforts have been focused on the following main objectives: optimization of vector extraction, isolation and purification of restriction enzymes and of DNA ligase T4, transformation and transfection experiments, construction of recombinant DNA. PMID:6097023

  2. Herlyn-Werner-Wunderlich and Prader-Willi syndromes: more than a coincidence?

    PubMed

    Fraga, Beatriz; Gomes, Catarina; Gouveia, Raquel; Oliveira, Graça

    2015-01-01

    A neonate with a prenatal diagnosis of left renal agenesis was born at 33 weeks gestation. A postnatal abdominal ultrasound confirmed the absence of the left kidney and revealed two non-divergent hemiuteri, consistent with the diagnosis of Herlyn-Werner-Wunderlich syndrome. During admission, significant axial hypotonia was noted, warranting additional investigations. Brain ultrasounds and MRI were normal, as were a preliminary metabolic study and comparative genomic hybridisation array. DNA methylation testing confirmed the diagnosis of Prader-Willi syndrome. The baby was discharged after 70 days, breast feeding and with modest hypotonia improvement. PMID:26491004

  3. Divergent cellular phenotypes of human and mouse cells lacking the Werner syndrome RecQ helicase

    PubMed Central

    Dhillon, Kiranjit K.; Sidorova, Julia M.; Albertson, Tina M.; Anderson, Judith B.; Ladiges, Warren C.; Rabinovitch, Peter S.; Preston, Bradley D.; Monnat, Raymond J.

    2009-01-01

    Werner syndrome (WS) is a human autosomal recessive genetic instability and cancer predisposition syndrome with features of premature aging. Several genetically determined mouse models of WS have been generated, however none develops features of premature aging or an elevated risk of neoplasia unless additional genetic perturbations are introduced. In order to determine whether differences in cellular phenotype could explain the discrepant phenotypes of Wrn−/− mice and WRN-deficient humans, we compared the cellular phenotype of newly derived Wrn−/− mouse primary fibroblasts with previous analyses of primary and transformed fibroblasts from WS patients and with newly derived, WRN-depleted human primary fibroblasts. These analyses confirmed previously reported cellular phenotypes of WRN-mutant and WRN-deficient human fibroblasts, and demonstrated that the human WRN-deficient cellular phenotype can be detected in cells grown in 5% or in 20% oxygen. In contrast, we did not identify prominent cellular phenotypes present in WRN-deficient human cells in Wrn−/− mouse fibroblasts. Our results indicate that human and mouse fibroblasts have different functional requirements for WRN protein, and that the absence of a strong cellular phenotype may in part explain the failure of Wrn−/− mice to develop an organismal phenotype resembling Werner syndrome. PMID:19896421

  4. POLD1 Germline Mutations in Patients Initially Diagnosed with Werner Syndrome.

    PubMed

    Lessel, Davor; Hisama, Fuki M; Szakszon, Katalin; Saha, Bidisha; Sanjuanelo, Alexander Barrios; Salbert, Bonnie A; Steele, Pamela D; Baldwin, Jennifer; Brown, W Ted; Piussan, Charles; Plauchu, Henri; Szilvássy, Judit; Horkay, Edit; Högel, Josef; Martin, George M; Herr, Alan J; Oshima, Junko; Kubisch, Christian

    2015-11-01

    Segmental progeroid syndromes are rare, heterogeneous disorders characterized by signs of premature aging affecting more than one tissue or organ. A prototypic example is the Werner syndrome (WS), caused by biallelic germline mutations in the Werner helicase gene (WRN). While heterozygous lamin A/C (LMNA) mutations are found in a few nonclassical cases of WS, another 10%-15% of patients initially diagnosed with WS do not have mutations in WRN or LMNA. Germline POLD1 mutations were recently reported in five patients with another segmental progeroid disorder: mandibular hypoplasia, deafness, progeroid features syndrome. Here, we describe eight additional patients with heterozygous POLD1 mutations, thereby substantially expanding the characterization of this new example of segmental progeroid disorders. First, we identified POLD1 mutations in patients initially diagnosed with WS. Second, we describe POLD1 mutation carriers without clinically relevant hearing impairment or mandibular underdevelopment, both previously thought to represent obligate diagnostic features. These patients also exhibit a lower incidence of metabolic abnormalities and joint contractures. Third, we document postnatal short stature and premature greying/loss of hair in POLD1 mutation carriers. We conclude that POLD1 germline mutations can result in a variably expressed and probably underdiagnosed segmental progeroid syndrome.

  5. POLD1 Germline Mutations in Patients Initially Diagnosed with Werner Syndrome.

    PubMed

    Lessel, Davor; Hisama, Fuki M; Szakszon, Katalin; Saha, Bidisha; Sanjuanelo, Alexander Barrios; Salbert, Bonnie A; Steele, Pamela D; Baldwin, Jennifer; Brown, W Ted; Piussan, Charles; Plauchu, Henri; Szilvássy, Judit; Horkay, Edit; Högel, Josef; Martin, George M; Herr, Alan J; Oshima, Junko; Kubisch, Christian

    2015-11-01

    Segmental progeroid syndromes are rare, heterogeneous disorders characterized by signs of premature aging affecting more than one tissue or organ. A prototypic example is the Werner syndrome (WS), caused by biallelic germline mutations in the Werner helicase gene (WRN). While heterozygous lamin A/C (LMNA) mutations are found in a few nonclassical cases of WS, another 10%-15% of patients initially diagnosed with WS do not have mutations in WRN or LMNA. Germline POLD1 mutations were recently reported in five patients with another segmental progeroid disorder: mandibular hypoplasia, deafness, progeroid features syndrome. Here, we describe eight additional patients with heterozygous POLD1 mutations, thereby substantially expanding the characterization of this new example of segmental progeroid disorders. First, we identified POLD1 mutations in patients initially diagnosed with WS. Second, we describe POLD1 mutation carriers without clinically relevant hearing impairment or mandibular underdevelopment, both previously thought to represent obligate diagnostic features. These patients also exhibit a lower incidence of metabolic abnormalities and joint contractures. Third, we document postnatal short stature and premature greying/loss of hair in POLD1 mutation carriers. We conclude that POLD1 germline mutations can result in a variably expressed and probably underdiagnosed segmental progeroid syndrome. PMID:26172944

  6. Search and Insights into Novel Genetic Alterations Leading to Classical and Atypical Werner Syndrome

    PubMed Central

    Oshima, Junko; Hisama, Fuki M.

    2014-01-01

    Segmental progeroid syndromes are a group of disorders with multiple features resembling accelerated aging. Adult-onset Werner syndrome (WS) and childhood-onset Hutchinson-Gilford progeria syndrome (HGPS) are the best known examples. The discovery of genes responsible for such syndromes has facilitated our understanding of the basic mechanisms of aging as well as the pathogenesis of other common, age-related diseases. Our International Registry of Werner Syndrome accesses progeroid pedigrees from all over the world, including those for whom we have ruled out a mutation at the WRN locus. Cases without WRN mutations are operationally categorized as “atypical WS” (AWS). In 2003, we identified LMNA mutations among a subset of AWS cases using a candidate gene approach. As of 2013, the Registry has 142 WS patients with WRN mutations, 11 AWS patients with LMNA mutations, and 49 AWS patients that have neither WRN nor LMNA mutations. Efforts are underway to identify the responsible genes for AWS with unknown genetic causes. While WS and AWS are rare disorders, the causative genes have been shown to have much wider implications for cancer, cardiovascular disease and the biology of aging. Remarkably, centenarian studies revealed WRN and LMNA polymorphic variants among those who have escaped various geriatric disorders. PMID:24401204

  7. Catalytic activities of Werner protein are affected by adduction with 4-hydroxy-2-nonenal

    PubMed Central

    Czerwińska, Jolanta; Poznański, Jarosław; Dębski, Janusz; Bukowy, Zuzanna; Bohr, Vilhelm A.; Tudek, Barbara; Speina, Elżbieta

    2014-01-01

    4-Hydroxy-2-nonenal (HNE) is a reactive α,β-unsaturated aldehyde generated during oxidative stress and subsequent peroxidation of polyunsaturated fatty acids. Here, Werner protein (WRN) was identified as a novel target for modification by HNE. Werner syndrome arises through mutations in the WRN gene that encodes the RecQ DNA helicase which is critical for maintaining genomic stability. This hereditary disease is associated with chromosomal instability, premature aging and cancer predisposition. WRN appears to participate in the cellular response to oxidative stress and cells devoid of WRN display elevated levels of oxidative DNA damage. We demonstrated that helicase/ATPase and exonuclease activities of HNE-modified WRN protein were inhibited both in vitro and in immunocomplexes purified from the cell extracts. Sites of HNE adduction in human WRN were identified at Lys577, Cys727, His1290, Cys1367, Lys1371 and Lys1389. We applied in silico modeling of the helicase and RQC domains of WRN protein with HNE adducted to Lys577 and Cys727 and provided a potential mechanism of the observed deregulation of the protein catalytic activities. In light of the obtained results, we postulate that HNE adduction to WRN is a post-translational modification, which may affect WRN conformational stability and function, contributing to features and diseases associated with premature senescence. PMID:25170083

  8. POLD1 Germline Mutations in Patients Initially Diagnosed with Werner Syndrome

    PubMed Central

    Lessel, Davor; Hisama, Fuki M.; Szakszon, Katalin; Saha, Bidisha; Sanjuanelo, Alexander Barrios; Salbert, Bonnie A.; Steele, Pamela D.; Baldwin, Jennifer; Brown, W. Ted; Piussan, Charles; Plauchu, Henri; Szilvássy, Judit; Horkay, Edit; Hoögel, Josef; Martin, George M.; Herr, Alan J.; Oshima, Junko; Kubisch, Christian

    2015-01-01

    Segmental progeroid syndromes are rare, heterogeneous disorders characterized by signs of premature aging affecting more than one tissue or organ. A prototypic example is the Werner syndrome (WS), caused by biallelic germline mutations in the Werner helicase gene (WRN). While heterozygous lamin A/C (LMNA) mutations are found in a few nonclassical cases of WS, another 10%–15% of patients initially diagnosed with WS do not have mutations in WRN or LMNA. Germline POLD1 mutations were recently reported in five patients with another segmental progeroid disorder: mandibular hypoplasia, deafness, progeroid features syndrome. Here, we describe eight additional patients with heterozygous POLD1 mutations, thereby substantially expanding the characterization of this new example of segmental progeroid disorders. First, we identified POLD1 mutations in patients initially diagnosed with WS. Second, we describe POLD1 mutation carriers without clinically relevant hearing impairment or mandibular underdevelopment, both previously thought to represent obligate diagnostic features. These patients also exhibit a lower incidence of metabolic abnormalities and joint contractures. Third, we document postnatal short stature and premature greying/loss of hair in POLD1 mutation carriers. We conclude that POLD1 germline mutations can result in a variably expressed and probably underdiagnosed segmental progeroid syndrome. PMID:26172944

  9. A numerical analysis of Stefan problems for generalized multi-dimensional phase-change structures using the enthalpy transforming model

    NASA Technical Reports Server (NTRS)

    Cao, Yiding; Faghri, Amir; Chang, Won Soon

    1989-01-01

    An enthalpy transforming scheme is proposed to convert the energy equation into a nonlinear equation with the enthalpy, E, being the single dependent variable. The existing control-volume finite-difference approach is modified so it can be applied to the numerical performance of Stefan problems. The model is tested by applying it to a three-dimensional freezing problem. The numerical results are in agreement with those existing in the literature. The model and its algorithm are further applied to a three-dimensional moving heat source problem showing that the methodology is capable of handling complicated phase-change problems with fixed grids.

  10. Aberrant DNA methylation profiles in the premature aging disorders Hutchinson-Gilford Progeria and Werner syndrome.

    PubMed

    Heyn, Holger; Moran, Sebastian; Esteller, Manel

    2013-01-01

    DNA methylation gradiently changes with age and is likely to be involved in aging-related processes with subsequent phenotype changes and increased susceptibility to certain diseases. The Hutchinson-Gilford Progeria (HGP) and Werner Syndrome (WS) are two premature aging diseases showing features of common natural aging early in life. Mutations in the LMNA and WRN genes were associated to disease onset; however, for a subset of patients the underlying causative mechanisms remain elusive. We aimed to evaluate the role of epigenetic alteration on premature aging diseases by performing comprehensive DNA methylation profiling of HGP and WS patients. We observed profound changes in the DNA methylation landscapes of WRN and LMNA mutant patients, which were narrowed down to a set of aging related genes and processes. Although of low overall variance, non-mutant patients revealed differential DNA methylation at distinct loci. Hence, we propose DNA methylation to have an impact on premature aging diseases.

  11. Active Control of Repetitive Structural Transitions between Replication Forks and Holliday Junctions by Werner Syndrome Helicase.

    PubMed

    Shin, Soochul; Lee, Jinwoo; Yoo, Sangwoon; Kulikowicz, Tomasz; Bohr, Vilhelm A; Ahn, Byungchan; Hohng, Sungchul

    2016-08-01

    The reactivation of stalled DNA replication via fork regression invokes Holliday junction formation, branch migration, and the recovery of the replication fork after DNA repair or error-free DNA synthesis. The coordination mechanism for these DNA structural transitions by molecular motors, however, remains unclear. Here we perform single-molecule fluorescence experiments with Werner syndrome protein (WRN) and model replication forks. The Holliday junction is readily formed once the lagging arm is unwound, and migrated unidirectionally with 3.2 ± 0.03 bases/s velocity. The recovery of the replication fork was controlled by branch migration reversal of WRN, resulting in repetitive fork regression. The Holliday junction formation, branch migration, and migration direction reversal are all ATP dependent, revealing that WRN uses the energy of ATP hydrolysis to actively coordinate the structural transitions of DNA.

  12. Observability, Anschaulichkeit and Abstraction: A Journey into Werner Heisenberg's Science and Philosophy

    NASA Astrophysics Data System (ADS)

    Lacki, Jan

    2003-09-01

    Werner Heisenberg was one of the greatest physicists of the 20th century. He participated as a front rank actor in the shaping of a good part of XXth century physics and directly witnessed most of the intellectual struggles which led to what he called “Wandlungen in den Grundlagen der exakten Naturwissenschaft”. This expression is borrowed from one of the many talks and writings he devoted to the analysis of the scientific and philosophical implications of his, and his fellows physicists, findings. Indeed, Heisenberg's scientific activity increasingly reflected his more general intellectual views. This makes him another magnificent representative of a glorious linage going from the remote times of modern science to Einstein, Bohr and the like. This “philosophical” vein started early in his scientific life, and got stronger with time, prompted by the highly demanding scientific, but also social and political context of his mature years.

  13. Werner states and the two-spinors Heisenberg anti-ferromagnet

    NASA Astrophysics Data System (ADS)

    Batle, J.; Casas, M.; Plastino, A.; Plastino, A. R.

    2005-08-01

    We ascertain, following ideas of Arnesen, Bose, and Vedral concerning thermal entanglement [Phys. Rev. Lett. 87 (2001) 017901] and using the statistical tool called entropic non-triviality [P.W. Lamberti, M.T. Martin, A. Plastino, O.A. Rosso, Physica A 334 (2004) 119], that there is a one-to-one correspondence between (i) the mixing coefficient x of a Werner state, on the one hand, and (ii) the temperature T of the one-dimensional Heisenberg two-spin chain with a magnetic field B along the z-axis, on the other one. This is true for each value of B below a certain critical value B. The pertinent mapping depends on the particular B-value one selects within such a range.

  14. A Werner syndrome stem cell model unveils heterochromatin alterations as a driver of human aging

    PubMed Central

    Zhang, Weiqi; Li, Jingyi; Suzuki, Keiichiro; Qu, Jing; Wang, Ping; Zhou, Junzhi; Liu, Xiaomeng; Ren, Ruotong; Xu, Xiuling; Ocampo, Alejandro; Yuan, Tingting; Yang, Jiping; Li, Ying; Shi, Liang; Guan, Dee; Pan, Huize; Duan, Shunlei; Ding, Zhichao; Li, Mo; Yi, Fei; Bai, Ruijun; Wang, Yayu; Chen, Chang; Yang, Fuquan; Li, Xiaoyu; Wang, Zimei; Aizawa, Emi; Goebl, April; Soligalla, Rupa Devi; Reddy, Pradeep; Esteban, Concepcion Rodriguez; Tang, Fuchou; Liu, Guang-Hui; Belmonte, Juan Carlos Izpisua

    2015-01-01

    Werner syndrome (WS) is a premature aging disorder caused by WRN protein deficiency. Here, we report on the generation of a human WS model in human embryonic stem cells (ESCs). Differentiation of WRN-null ESCs to mesenchymal stem cells (MSCs) recapitulates features of premature cellular aging, a global loss of H3K9me3, and changes in heterochromatin architecture. We show that WRN associates with heterochromatin proteins SUV39H1 and HP1α and nuclear lamina-heterochromatin anchoring protein LAP2β. Targeted knock-in of catalytically inactive SUV39H1 in wild-type MSCs recapitulates accelerated cellular senescence, resembling WRN-deficient MSCs. Moreover, decrease in WRN and heterochromatin marks are detected in MSCs from older individuals. Our observations uncover a role for WRN in maintaining heterochromatin stability and highlight heterochromatin disorganization as a potential determinant of human aging. PMID:25931448

  15. Robustness measure of hybrid intra-particle entanglement, discord, and classical correlation with initial Werner state

    NASA Astrophysics Data System (ADS)

    Saha, P.; Sarkar, D.

    2016-02-01

    Quantum information processing is largely dependent on the robustness of non-classical correlations, such as entanglement and quantum discord. However, all the realistic quantum systems are thermodynamically open and lose their coherence with time through environmental interaction. The time evolution of quantum entanglement, discord, and the respective classical correlation for a single, spin-1/2 particle under spin and energy degrees of freedom, with an initial Werner state, has been investigated in the present study. The present intra-particle system is considered to be easier to produce than its inter-particle counterpart. Experimentally, this type of system may be realized in the well-known Penning trap. The most stable correlation was identified through maximization of a system-specific global objective function. Quantum discord was found to be the most stable, followed by the classical correlation. Moreover, all the correlations were observed to attain highest robustness under initial Bell state, with minimum possible dephasing and decoherence parameters.

  16. Redescription Cyrtodactylus lateralis (Werner) (Squamata: Gekkonidae) and Phylogeny of the Prehensile-tailed Cyrtodactylus.

    PubMed

    Harvey, Michael B; O'connell, Kyle A; Wostl, Elijah; Riyanto, Awal; Kurniawan, Nia; Smith, Eric N; Grismer, L Lee

    2016-01-01

    We redescribe Cyrtodactylus lateralis (Werner) on the basis of new specimens. Cyrtodactylus lateralis is a prehensile-tailed species, known from scattered lowland to mid-elevation localities in northern Sumatra. The prehensile-tailed Cyrtodactylus are more speciose and have a wider distribution than previously thought. This group includes a mainland SE Asian clade consisting of C. elok, C. interdigitalis, and C. brevipalmatus and an insular clade containing C. durio, C. lateralis, C. nuaulu, C. serratus, C. spinosus, and C. stresemanni. However, a distinctive color pattern in the Wallacean and Papuan species and uncertainty surrounding the type locality of C. stresemanni raise unresolved questions about the inclusiveness of the insular clade. DNA sequence data supports a close relationship between C. elok and C. interdigitalis, but also reveals that C. lateralis and C. durio are not closely related to these species. PMID:27394838

  17. Entanglement Evolution of the Extended Werner-like State under the Influence of Different Noisy Channels

    NASA Astrophysics Data System (ADS)

    Jiang, Li-Nan; Ma, Jing; Yu, Si-Yuan; Tan, Li-Ying; Ran, Qi-Wen

    2015-02-01

    The entanglement evolution of the bipartite quantum system which is initially prepared in extended Werner-like state under the influence of independent or collective noisy channels are investigated by solving the master equation in Lindblad form. With the aid of the concurrence, we find that the initial state can preserve more entanglement in certain region when it is transmitted through the collective Pauli σ x or σ y noisy channel than the corresponding independent noisy channel. For the Pauli σ z or the depolarizing channel, however, the collective decoherence can speed up the process of entanglement decay. Meanwhile, we show that the purity of initial state has a great influence on the region which the entanglement can be preserved.

  18. [From Nobody to Nobel laureate? The case of Werner Forßmann].

    PubMed

    Hansson, N; Packy, L-M; Halling, T; Groß, D; Fangerau, H

    2015-03-01

    The surgeon and urologist Werner Forßmann (1904-1979) was awarded the Nobel Prize for Physiology or Medicine in 1956. At the time of the prize ceremony, several newspapers portrayed Forssmann as an unknown rural physician who suddenly had become an international star. Drawing on nominations and reports in the Nobel Prize Archive for Physiology or Medicine in Stockholm as well as correspondence from the private archive of the Forßmann family, this paper reconstructs why the Nobel Committee chose to award Forßmann. We show that Forssmann's work was appreciated in medical textbooks and that he enjoyed a relatively sound reputation in the international scientific community even before he became a Nobel Prize laureate. At a more general level, we use his example to explore some mechanisms of scientific recognition. PMID:25784449

  19. [From Nobody to Nobel laureate? The case of Werner Forßmann].

    PubMed

    Hansson, N; Packy, L-M; Halling, T; Groß, D; Fangerau, H

    2015-03-01

    The surgeon and urologist Werner Forßmann (1904-1979) was awarded the Nobel Prize for Physiology or Medicine in 1956. At the time of the prize ceremony, several newspapers portrayed Forssmann as an unknown rural physician who suddenly had become an international star. Drawing on nominations and reports in the Nobel Prize Archive for Physiology or Medicine in Stockholm as well as correspondence from the private archive of the Forßmann family, this paper reconstructs why the Nobel Committee chose to award Forßmann. We show that Forssmann's work was appreciated in medical textbooks and that he enjoyed a relatively sound reputation in the international scientific community even before he became a Nobel Prize laureate. At a more general level, we use his example to explore some mechanisms of scientific recognition.

  20. Herlyn Werner Wunderlich Syndrome with Hematocolpos: An Unusual Case Report of Full Diagnostic Approach and Treatment

    PubMed Central

    Bhoil, Rohit; Ahluwalia, Ajay; Chauhan, Narvir

    2016-01-01

    Herlyn-Werner-Wunderlich (HWW) syndrome is an uncommon combined müllerian duct anomalies (MDAs) and mesonephric duct malformation of female urogenital tract characterized by uterus didelphys and obstructed hemi-vagina and ipsilateral renal agenesis (OHVIRA) syndrome. We present a rare and unusual case of this syndrome in a 19 year-old female who suffered from hypomenorrhoea and abdominal pain. She had an obstructed hemi-vagina on right side which led to marked distention of ipsilateral cervix, while proximal hemi-vagina compressed the contralateral side causing its partial obstruction resulting in hypomenorrhoea. Understanding the imaging findings of this rare condition is important for early diagnosis in order to prevent complications which may lead to infertility. PMID:27123211

  1. Prematurely aged children: molecular alterations leading to Hutchinson-Gilford progeria and Werner syndromes.

    PubMed

    Domínguez-Gerpe, Lourdes; Araújo-Vilar, David

    2008-12-01

    Ageing is thought to be a polygenic and stochastic process in which multiple mechanisms operate at the same time. At the level of the individual organism ageing is associated with a progressive deterioration of health and quality of life, sharing common features such as: alopecia and grey hair, loss of audition, macular degeneration, neurodegeneration, cardiovascular diseases, osteoporosis, cataract formation, type-2 diabetes, lipodystrophies; a generally increased susceptibility to infection, autoimmune disorders and diseases such as cancer; and an impaired ability to cope with stress. Recent studies of mechanisms involved in the ageing process are contributing to the identification of genes involved in longevity. Monogenic heritable disorders causing premature ageing, and animal models have contributed to the understanding of some of the characteristic organism-level features associated with human ageing. Werner syndrome and Hutchinson-Gilford progeria syndrome are the best characterized human disorders. Werner syndrome patients have a median life expectancy of 47 years with clinical conditions from the second decade of life. Hutchinson-Gilford progeria syndrome patients die at a median age of 11-13 years with clinical conditions appearing soon after birth. In both syndromes, alterations in specific genes have been identified, with mutations in the WRN and LMNA genes respectively being the most closely associated with each syndrome. Results from molecular studies strongly suggest an increase in DNA damage and cell senescence as the underlying mechanism of pathological premature ageing in these two human syndromes. The same general mechanism has also been observed in human cells undergoing the normal ageing process. In the present article the molecular mechanisms currently proposed for explaining these two syndromes, which may also partly explain the normal ageing process, are reviewed.

  2. Genetics and aging; the Werner syndrome as a segmental progeroid syndrome.

    PubMed

    Martin, G M

    1985-01-01

    The maximum lifespan potential is a constitutional feature of speciation and must be subject to polygenic controls acting both in the domain of development and in the domain of the maintenance of macromolecular integrity. The enormous genetic heterogeneity that characterizes our own species, the complexities of numerous nature-nurture interactions, and the quantitative and qualitative variations of the senescent phenotype that are observed suggest that precise patterns of aging in each of us may be unique. Patterns of aging may also differ sharply among species (for example, semelparous vs. multiparous mammals). Some potential common denominators, however, allow one to identify progeroid syndromes in man that could lead to the elucidation of important pathways of gene action. (The suffix "-oid" means "like"; it does not mean identity.) Unimodal progeroid syndromes (eg., familial dementia of the Alzheimer type, an autosomal dominant) can help us understand the pathogenesis of a particular aspect of the senescent phenotype of man. Segmental progeroid syndromes (eg. the Werner syndrome, an autosomal recessive) may be relevant to multiple aspects of the senescent phenotype. Some results of research on the Werner syndrome may be interpreted as support for "peripheral" as opposed to "central" theories of aging; they are consistent with the view that gene action in the domain of development (adolescence, in this instance) can set the stage for patterns of aging in the adult; they point to the importance of mesenchymal cell populations in the pathogenesis of age-related disorders; finally, they underscore the role of chromosomal instability, especially in the pathogenesis of neoplasia.

  3. Genetics and aging; the Werner syndrome as a segmental progeroid syndrome.

    PubMed

    Martin, G M

    1985-01-01

    The maximum lifespan potential is a constitutional feature of speciation and must be subject to polygenic controls acting both in the domain of development and in the domain of the maintenance of macromolecular integrity. The enormous genetic heterogeneity that characterizes our own species, the complexities of numerous nature-nurture interactions, and the quantitative and qualitative variations of the senescent phenotype that are observed suggest that precise patterns of aging in each of us may be unique. Patterns of aging may also differ sharply among species (for example, semelparous vs. multiparous mammals). Some potential common denominators, however, allow one to identify progeroid syndromes in man that could lead to the elucidation of important pathways of gene action. (The suffix "-oid" means "like"; it does not mean identity.) Unimodal progeroid syndromes (eg., familial dementia of the Alzheimer type, an autosomal dominant) can help us understand the pathogenesis of a particular aspect of the senescent phenotype of man. Segmental progeroid syndromes (eg. the Werner syndrome, an autosomal recessive) may be relevant to multiple aspects of the senescent phenotype. Some results of research on the Werner syndrome may be interpreted as support for "peripheral" as opposed to "central" theories of aging; they are consistent with the view that gene action in the domain of development (adolescence, in this instance) can set the stage for patterns of aging in the adult; they point to the importance of mesenchymal cell populations in the pathogenesis of age-related disorders; finally, they underscore the role of chromosomal instability, especially in the pathogenesis of neoplasia. PMID:3909765

  4. Werner's syndrome: a review of recent research with an analysis of connective tissue metabolism, growth control of cultured cells, and chromosomal aberrations.

    PubMed

    Salk, D

    1982-01-01

    Werner's syndrome is a rare, autosomal recessive condition with multiple progeroid features, but it is an imitation of aging rather than accelerated or premature senescence. Somatic chromosome aberrations occur in multiple tissues in vivo and in vitro, and there is an increased incidence of neoplasia. Thus. Werner's syndrome can be classified in the group of chromosome instability syndromes. Recent findings provide additional support for the concept that there is an aberration of connective tissue metabolism in Werner's syndrome, but it is unclear whether this is a primary or secondary manifestation of the underlying genetic defect. Abnormal growth characteristics are observed in cultured skin fibroblast-like cells and this provides another avenue for current research. Identification of the basic genetic defect in Werner's syndrome might clarify our understanding of the normal aging process in general, or might elucidate specific aspects such as the development of neoplasia, atherosclerosis, diabetes, or osteoporosis.

  5. On the Maxwell-Stefan approach to diffusion: a general resolution in the transient regime for one-dimensional systems.

    PubMed

    Leonardi, Erminia; Angeli, Celestino

    2010-01-14

    The diffusion process in a multicomponent system can be formulated in a general form by the generalized Maxwell-Stefan equations. This formulation is able to describe the diffusion process in different systems, such as, for instance, bulk diffusion (in the gas, liquid, and solid phase) and diffusion in microporous materials (membranes, zeolites, nanotubes, etc.). The Maxwell-Stefan equations can be solved analytically (only in special cases) or by numerical approaches. Different numerical strategies have been previously presented, but the number of diffusing species is normally restricted, with only few exceptions, to three in bulk diffusion and to two in microporous systems, unless simplifications of the Maxwell-Stefan equations are considered. In the literature, a large effort has been devoted to the derivation of the analytic expression of the elements of the Fick-like diffusion matrix and therefore to the symbolic inversion of a square matrix with dimensions n x n (n being the number of independent components). This step, which can be easily performed for n = 2 and remains reasonable for n = 3, becomes rapidly very complex in problems with a large number of components. This paper addresses the problem of the numerical resolution of the Maxwell-Stefan equations in the transient regime for a one-dimensional system with a generic number of components, avoiding the definition of the analytic expression of the elements of the Fick-like diffusion matrix. To this aim, two approaches have been implemented in a computational code; the first is the simple finite difference second-order accurate in time Crank-Nicolson scheme for which the full mathematical derivation and the relevant final equations are reported. The second is based on the more accurate backward differentiation formulas, BDF, or Gear's method (Shampine, L. F. ; Gear, C. W. SIAM Rev. 1979, 21, 1.), as implemented in the Livermore solver for ordinary differential equations, LSODE (Hindmarsh, A. C. Serial

  6. On the Maxwell-Stefan approach to diffusion: a general resolution in the transient regime for one-dimensional systems.

    PubMed

    Leonardi, Erminia; Angeli, Celestino

    2010-01-14

    The diffusion process in a multicomponent system can be formulated in a general form by the generalized Maxwell-Stefan equations. This formulation is able to describe the diffusion process in different systems, such as, for instance, bulk diffusion (in the gas, liquid, and solid phase) and diffusion in microporous materials (membranes, zeolites, nanotubes, etc.). The Maxwell-Stefan equations can be solved analytically (only in special cases) or by numerical approaches. Different numerical strategies have been previously presented, but the number of diffusing species is normally restricted, with only few exceptions, to three in bulk diffusion and to two in microporous systems, unless simplifications of the Maxwell-Stefan equations are considered. In the literature, a large effort has been devoted to the derivation of the analytic expression of the elements of the Fick-like diffusion matrix and therefore to the symbolic inversion of a square matrix with dimensions n x n (n being the number of independent components). This step, which can be easily performed for n = 2 and remains reasonable for n = 3, becomes rapidly very complex in problems with a large number of components. This paper addresses the problem of the numerical resolution of the Maxwell-Stefan equations in the transient regime for a one-dimensional system with a generic number of components, avoiding the definition of the analytic expression of the elements of the Fick-like diffusion matrix. To this aim, two approaches have been implemented in a computational code; the first is the simple finite difference second-order accurate in time Crank-Nicolson scheme for which the full mathematical derivation and the relevant final equations are reported. The second is based on the more accurate backward differentiation formulas, BDF, or Gear's method (Shampine, L. F. ; Gear, C. W. SIAM Rev. 1979, 21, 1.), as implemented in the Livermore solver for ordinary differential equations, LSODE (Hindmarsh, A. C. Serial

  7. Multicomponent diffusion in molten salt NaF-ZrF4: Dynamical correlations and Maxwell-Stefan diffusivities

    NASA Astrophysics Data System (ADS)

    Baig, Mohammad Saad; Chakraborty, Brahmananda; Ramaniah, Lavanya M.

    2016-05-01

    NaF-ZrF4 is used as a waste incinerator and as a coolant in Generation IV reactors.Structural and dynamical properties of molten NaF-ZrF4 system were studied along with Onsagercoefficients and Maxwell-Stefan (MS) Diffusivities applying Green-Kubo formalism and molecular dynamics (MD) simulations. The zirconium ions are found to be 8 fold coordinated with fluoride ions for all temperatures and concentrations. All the diffusive flux correlations show back-scattering. Even though the MS diffusivities are expected to depend very lightly on the composition because of decoupling of thermodynamic factor, the diffusivity ĐNa-F shows interesting behavior with the increase in concentration of ZrF4. This is because of network formation in NaF-ZrF4. Positive entropy constraints have been plotted to authenticate negative diffusivities observed.

  8. The generalized correlation for the evaluation of the influence of the Stefan flow on the heat transfer coefficient

    NASA Astrophysics Data System (ADS)

    Baskakov, A. P.; Rakov, O. A.

    2013-11-01

    The analytical equations for the steady-state heat-and-mass transfer in the steam evaporation/condensation processes from the steam-gas mixtures on the planar and spherical surfaces are derived. The vapor flow through the motionless dry gas is considered according to the method proposed by Maxwell for the solution of the diffusion problems. The relationships for the calculation of the coefficients taking into account an increase in the mass output and an increase or a decrease in the heat emission (depending on the directions of the heat-and-mass flows) as a result of the influence of the Stefan flow are presented. The derived relationships can be used to calculate the apparatuses in which the steam evaporation or condensation from the steam-gas mixture occurs (the coolers of the vapor from deaerators, the apparatuses for the deep utilization of the heat of the combustion products, the condensation boilers, etc.).

  9. Hawking radiation and the Stefan-Boltzmann law: The effective radius of the black-hole quantum atmosphere

    NASA Astrophysics Data System (ADS)

    Hod, Shahar

    2016-06-01

    It has recently been suggested (S.B. Giddings (2016) [2]) that the Hawking black-hole radiation spectrum originates from an effective quantum "atmosphere' which extends well outside the black-hole horizon. In particular, comparing the Hawking radiation power of a (3 + 1)-dimensional Schwarzschild black hole of horizon radius rH with the familiar Stefan-Boltzmann radiation power of a (3 + 1)-dimensional flat space perfect blackbody emitter, Giddings concluded that the source of the Hawking semi-classical black-hole radiation is a quantum region outside the Schwarzschild black-hole horizon whose effective radius rA is characterized by the relation Δr ≡rA -rH ∼rH. It is of considerable physical interest to test the general validity of Giddings's intriguing conclusion. To this end, we study the Hawking radiation of (D + 1)-dimensional Schwarzschild black holes. We find that the dimensionless radii rA /rH which characterize the black-hole quantum atmospheres, as determined from the Hawking black-hole radiation power and the (D + 1)-dimensional Stefan-Boltzmann radiation law, are a decreasing function of the number D + 1 of spacetime dimensions. In particular, it is shown that radiating (D + 1)-dimensional Schwarzschild black holes are characterized by the relation (rA -rH) /rH ≪ 1 in the large D ≫ 1 regime. Our results therefore suggest that, at least in some physical cases, the Hawking emission spectrum originates from quantum excitations very near the black-hole horizon.

  10. Sowing Black Hole Seeds: Forming Direct Collapse Black Holes With Realistic Lyman-Werner Radiation Fields in Cosmological Simulations

    NASA Astrophysics Data System (ADS)

    Holley-Bockelmann, Kelly; Dunn, Glenna; Bellovary, Jillian M.; Christensen, Charlotte

    2016-01-01

    Luminous quasars detected at redshifts z > 6 require that the first black holes form early and grow to ~109 solar masses within one Gyr. Our work uses cosmological simulations to study the formation and early growth of direct collapse black holes. In the pre-reionization epoch, molecular hydrogen (H2) causes gas to fragment and form Population III stars, but Lyman-Werner radiation can suppress H2 formation and allow gas to collapse directly into a massive black hole. The critical flux required to inhibit H2 formation, Jcrit, is hotly debated, largely due to the uncertainties in the source radiation spectrum, H2 self-shielding, and collisional dissociation rates. Here, we test the power of the direct collapse model in a non-uniform Lyman-Werner radiation field, using an updated version of the SPH+N-body tree code Gasoline with H2 non-equilibrium abundance tracking, H2 cooling, and a modern SPH implementation. We vary Jcrit from 30 to 104 J21 to study the effect on seed black holes, focusing on black hole formation as a function of environment, halo mass, metallicity, and proximity of the Lyman-Werner source. We discuss the constraints on massive black hole occupation fraction in the quasar epoch, and implications for reionization, high-redshift X-ray background radiation, and gravitational waves.

  11. Partial lipodystrophy with severe insulin resistance and adult progeria Werner syndrome

    PubMed Central

    2013-01-01

    Background Laminopathies, due to mutations in LMNA, encoding A type-lamins, can lead to premature ageing and/or lipodystrophic syndromes, showing that these diseases could have close physiopathological relationships. We show here that lipodystrophy and extreme insulin resistance can also reveal the adult progeria Werner syndrome linked to mutations in WRN, encoding a RecQ DNA helicase. Methods We analysed the clinical and biological features of two women, aged 32 and 36, referred for partial lipodystrophic syndrome which led to the molecular diagnosis of Werner syndrome. Cultured skin fibroblasts from one patient were studied. Results Two normal-weighted women presented with a partial lipodystrophic syndrome with hypertriglyceridemia and liver steatosis. One of them had also diabetes. Both patients showed a peculiar, striking lipodystrophic phenotype with subcutaneous lipoatrophy of the four limbs contrasting with truncal and abdominal fat accumulation. Their oral glucose tolerance tests showed extremely high levels of insulinemia, revealing major insulin resistance. Low serum levels of sex-hormone binding globulin and adiponectin suggested a post-receptor insulin signalling defect. Other clinical features included bilateral cataracts, greying hair and distal skin atrophy. We observed biallelic WRN null mutations in both women (p.Q748X homozygous, and compound heterozygous p.Q1257X/p.M1329fs). Their fertility was decreased, with preserved menstrual cycles and normal follicle-stimulating hormone levels ruling out premature ovarian failure. However undetectable anti-müllerian hormone and inhibin B indicated diminished follicular ovarian reserve. Insulin-resistance linked ovarian hyperandrogenism could also contribute to decreased fertility, and the two patients became pregnant after initiation of insulin-sensitizers (metformin). Both pregnancies were complicated by severe cervical incompetence, leading to the preterm birth of a healthy newborn in one case, but to a

  12. The Werner's Syndrome RecQ helicase/exonuclease at the nexus of cancer and aging.

    PubMed

    Chun, Stephen G; Shaeffer, David S; Bryant-Greenwood, Peter K

    2011-03-01

    Werner's Syndrome (WS) or adult-onset progeria is an autosomal recessive disorder of accelerated aging caused by mutations of the DNA RecQ helicase/exonuclease (WRN). WRN is an ATP-dependent helicase with 3' to 5' DNA exonuclease activity that regulates the replicative potential of dividing cells, and WRN loss-of-function mutations promote cellular senescence and neoplastic transformation. These molecular findings translate clinically into adult-onset progeria manifested by premature hair graying, dermal atrophy, cardiovascular disease, and cancer predilection along with a markedly reduced life expectancy. Recently, a patient with WS who developed pancreatic adenocarcinoma was identified in Honolulu suggesting a significant prevalence of loss-of-function WRN mutations in Hawaii's Japanese-American population. Based upon the indigenous Japanese WRN loss-of-function mutation heterozygote rate of 6 per 1,000, we speculate the possibility of approximately 1,200 heterozygotes in Hawaii. Our ongoing studies aim to evaluate Hawaii's true allelic prevalence of WRN loss-of-function mutations in the Japanese-American population, and the role of WRN silencing in sporadic cancers. In summary, WRN plays a nexus-like role in the complex interplay of cellular events that regulate aging, and analysis of WRN polymorphisms in Hawaii's population will generate novel insights to advance care for age-related pathologies.

  13. Werner and Bloom helicases are involved in DNA repair in a complementary fashion.

    PubMed

    Imamura, Osamu; Fujita, Kumiko; Itoh, Chie; Takeda, Shunichi; Furuichi, Yasuhiro; Matsumoto, Takehisa

    2002-01-31

    Werner syndrome (WS) is a recessive disorder characterized by premature senescence. Bloom syndrome (BS) is a recessive disorder characterized by short stature and immunodeficiency. A common characteristic of both syndromes is genomic instability leading to tumorigenesis. WRN and BLM genes causing WS and BS, encode proteins that are closely related to the RecQ helicase. We produced WRN-/-, BLM-/- and WRN(-/-)/BLM(-/-) mutants in the chicken B-cell line DT40. WRN-/- cells showed hypersensitivities to genotoxic agents, such as 4-nitroquinoline 1-oxide, camptothecin and methyl methanesulfonate. They also showed a threefold increase in targeted integration rate of exogenous DNAs, but not in sister chromatid exchange (SCE) frequency. BLM-/- cells showed hypersensitivities to the genotoxic agents as well as ultraviolet (UV) light, in addition to a 10-fold increase in targeted integration rate and an 11-fold increase in SCE frequency. In WRN(-/-)/BLM(-/-) cells, synergistically increased hypersensitivities to the genotoxic agents were observed whereas both SCE frequencies and targeted integration rates were partially diminished compared to the single mutants. Chromosomal aberrations were also synergistically increased in WRN(-/-)/BLM(-/-) cells when irradiated with UV light in late S to G(2) phases. These results suggest that both WRN and BLM may be involved in DNA repair in a complementary fashion. PMID:11840341

  14. Gene expression profiling in Werner syndrome closely resembles that of normal aging.

    PubMed

    Kyng, Kasper J; May, Alfred; Kølvraa, Steen; Bohr, Vilhelm A

    2003-10-14

    Werner syndrome (WS) is a premature aging disorder, displaying defects in DNA replication, recombination, repair, and transcription. It has been hypothesized that several WS phenotypes are secondary consequences of aberrant gene expression and that a transcription defect may be crucial to the development of the syndrome. We used cDNA microarrays to characterize the expression of 6,912 genes and ESTs across a panel of 15 primary human fibroblast cell lines derived from young donors, old donors, and WS patients. Of the analyzed genes, 6.3% displayed significant differences in expression when either WS or old donor cells were compared with young donor cells. This result demonstrates that the WS transcription defect is specific to certain genes. Transcription alterations in WS were strikingly similar to those in normal aging: 91% of annotated genes displayed similar expression changes in WS and in normal aging, 3% were unique to WS, and 6% were unique to normal aging. We propose that a defect in the transcription of the genes as identified in this study could produce many of the complex clinical features of WS. The remarkable similarity between WS and normal aging suggests that WS causes the acceleration of a normal aging mechanism. This finding supports the use of WS as an aging model and implies that the transcription alterations common to WS and normal aging represent general events in the aging process.

  15. The Werner syndrome. A model for the study of human aging.

    PubMed

    Nehlin, J O; Skovgaard, G L; Bohr, V A

    2000-06-01

    Human aging is a complex process that leads to the gradual deterioration of body functions with time. Various models to approach the study of aging have been launched over the years such as the genetic analysis of life span in the yeast S. cerevisiae, the worm C. elegans, the fruitfly, and mouse, among others. In human models, there have been extensive efforts using replicative senescence, the study of centenerians, comparisons of young versus old at the organismal, cellular, and molecular levels, and the study of premature aging syndromes to understand the mechanisms leading to aging. One good model for studying human aging is a rare autosomal recessive disorder known as the Werner syndrome (WS), which is characterized by accelerated aging in vivo and in vitro. A genetic defect implicated in WS was mapped to the WRN locus. Mutations in this gene are believed to be associated, early in adulthood, with clinical symptoms normally found in old individuals. WRN functions as a DNA helicase, and recent evidence, summarized in this review, suggests specific biochemical roles for this multifaceted protein. The interaction of WRN protein with RPA (replication protein A) and p53 will undoubtedly direct efforts to further dissect the genetic pathway(s) in which WRN protein functions in DNA metabolism and will help to unravel its contribution to the human aging process.

  16. Physical and functional interactions between Werner syndrome helicase and mismatch-repair initiation factors

    PubMed Central

    Saydam, Nurten; Kanagaraj, Radhakrishnan; Dietschy, Tobias; Garcia, Patrick L.; Peña-Diaz, Javier; Shevelev, Igor; Stagljar, Igor; Janscak, Pavel

    2007-01-01

    Werner syndrome (WS) is a severe recessive disorder characterized by premature aging, cancer predisposition and genomic instability. The gene mutated in WS encodes a bi-functional enzyme called WRN that acts as a RecQ-type DNA helicase and a 3′-5′ exonuclease, but its exact role in DNA metabolism is poorly understood. Here we show that WRN physically interacts with the MSH2/MSH6 (MutSα), MSH2/MSH3 (MutSβ) and MLH1/PMS2 (MutLα) heterodimers that are involved in the initiation of mismatch repair (MMR) and the rejection of homeologous recombination. MutSα and MutSβ can strongly stimulate the helicase activity of WRN specifically on forked DNA structures with a 3′-single-stranded arm. The stimulatory effect of MutSα on WRN-mediated unwinding is enhanced by a G/T mismatch in the DNA duplex ahead of the fork. The MutLα protein known to bind to the MutS α–heteroduplex complexes has no effect on WRN-mediated DNA unwinding stimulated by MutSα, nor does it affect DNA unwinding by WRN alone. Our data are consistent with results of genetic experiments in yeast suggesting that MMR factors act in conjunction with a RecQ-type helicase to reject recombination between divergent sequences. PMID:17715146

  17. Ethnic differences in thermoregulatory responses during resting, passive and active heating: application of Werner's adaptation model.

    PubMed

    Lee, Joo-Young; Wakabayashi, Hitoshi; Wijayanto, Titis; Hashiguchi, Nobuko; Saat, Mohamed; Tochihara, Yutaka

    2011-12-01

    For the coherent understanding of heat acclimatization in tropical natives, we compared ethnic differences between tropical and temperate natives during resting, passive and active heating conditions. Experimental protocols included: (1) a resting condition (an air temperature of 28°C with 50% RH), (2) a passive heating condition (28°C with 50% RH; leg immersion in a hot tub at a water temperature of 42°C), and (3) an active heating condition (32°C with 70% RH; a bicycle exercise). Morphologically and physically matched tropical natives (ten Malaysian males, MY) and temperate natives (ten Japanese males, JP) participated in all three trials. The results saw that: tropical natives had a higher resting rectal temperature and lower hand and foot temperatures at rest, smaller rise of rectal temperature and greater temperature rise in bodily extremities, and a lower sensation of thirst during passive and active heating than the matched temperate natives. It is suggested that tropical natives' homeostasis during heating is effectively controlled with the improved stability in internal body temperature and the increased capability of vascular circulation in extremities, with a lower thirst sensation. The enhanced stability of internal body temperature and the extended thermoregulatory capability of vascular circulation in the extremities of tropical natives can be interpreted as an interactive change to accomplish a thermal dynamic equilibrium in hot environments. These heat adaptive traits were explained by Wilder's law of initial value and Werner's process and controller adaptation model.

  18. Identification of gene sequences overexpressed in senescent and Werner syndrome human fibroblasts.

    PubMed

    Lecka-Czernik, B; Moerman, E J; Jones, R A; Goldstein, S

    1996-01-01

    The phenotype of replicative senescence is a dominant trait in human diploid fibroblasts (HDF). Therefore, we have sought to identify overexpressed and/or newly expressed causal genes by constructing and screening a subtracted cDNA library derived from polyA+RNA of prematurely senescent Werner syndrome (WS) HDF. We have identified 15 cDNA clones that are overexpressed in senescent and WS HDF. Among them are six known sequences coding for: acid sphingomyelinase, fibronectin, SPARC, nm23-metastasis suppressor protein, and two translation factors, eIF-2 beta and EF-1 alpha. Among the 10 unknown clones are: S1-5, which encodes a secreted protein containing EGF-like domains and paradoxically stimulates DNA synthesis of young HDF in an autocrine and paracrine manner, S1-3, which encodes a protein containing "zinc finger" domains, suggesting nucleic acid binding properties; S1-15, which shows sequence similarities to human alpha 2-chimerin; and S2-6, which represents a new member of the LIM family of proteins. The other five clones do not have any significant homology to known sequences. Steady-state mRNA levels of all gene sequences thus far studied are elevated in both WS and senescent normal HDF when compared to young HDF, which suggests that senescent and WS HDF enter a final common pathway where multiple gene overexpression may generate diverse antiproliferative mechanisms and pathogenic sequelae. PMID:8706786

  19. DNA damage accumulation and TRF2 degradation in atypical Werner syndrome fibroblasts with LMNA mutations.

    PubMed

    Saha, Bidisha; Zitnik, Galynn; Johnson, Simon; Nguyen, Quyen; Risques, Rosa A; Martin, George M; Oshima, Junko

    2013-01-01

    Segmental progeroid syndromes are groups of disorders with multiple features suggestive of accelerated aging. One subset of adult-onset progeroid syndromes, referred to as atypical Werner syndrome, is caused by mutations in the LMNA gene, which encodes a class of nuclear intermediate filaments, lamin A/C. We previously described rapid telomere attrition and accelerated replicative senescence in cultured fibroblasts overexpressing mutant lamin A. In this study, we investigated the cellular phenotypes associated with accelerated telomere shortening in LMNA mutant primary fibroblasts. In early passage primary fibroblasts with R133L or L140R LMNA mutations, shelterin protein components were already reduced while cells still retained telomere lengths comparable to those of controls. There was a significant inverse correlation between the degree of abnormal nuclear morphology and the level of TRF2, a shelterin subunit, suggesting a potential causal relationship. Stabilization of the telomeres via the introduction of the catalytic subunit of human telomerase, hTERT (human telomerase reverse transcriptase), did not prevent degradation of shelterin components, indicating that reduced TRF2 in LMNA mutants is not mediated by short telomeres. Interestingly, γ-H2AX foci (reflecting double strand DNA damage) in early passage LMNA mutant primary fibroblasts and LMNA mutant hTERT fibroblasts were markedly increased in non-telomeric regions of DNA. Our results raise the possibility that mutant lamin A/C causes global genomic instability with accumulation of non-telomeric DNA damage as an early event, followed by TRF2 degradation and telomere shortening.

  20. Acetylation of Werner syndrome protein (WRN): relationships with DNA damage, DNA replication and DNA metabolic activities

    PubMed Central

    Lozada, Enerlyn; Yi, Jingjie; Luo, Jianyuan; Orren, David K.

    2014-01-01

    Loss of WRN function causes Werner Syndrome, characterized by increased genomic instability, elevated cancer susceptibility and premature aging. Although WRN is subject to acetylation, phosphorylation and sumoylation, the impact of these modifications on WRN’s DNA metabolic function remains unclear. Here, we examined in further depth the relationship between WRN acetylation and its role in DNA metabolism, particularly in response to induced DNA damage. Our results demonstrate that endogenous WRN is acetylated somewhat under unperturbed conditions. However, levels of acetylated WRN significantly increase after treatment with certain DNA damaging agents or the replication inhibitor hydroxyurea. Use of DNA repair-deficient cells or repair pathway inhibitors further increase levels of acetylated WRN, indicating that induced DNA lesions and their persistence are at least partly responsible for increased acetylation. Notably, acetylation of WRN correlates with inhibition of DNA synthesis, suggesting that replication blockage might underlie this effect. Moreover, WRN acetylation modulates its affinity for and activity on certain DNA structures, in a manner that may enhance its relative specificity for physiological substrates. Our results also show that acetylation and deacetylation of endogenous WRN is a dynamic process, with sirtuins and other histone deacetylases contributing to WRN deacetylation. These findings advance our understanding of the dynamics of WRN acetylation under unperturbed conditions and following DNA damage induction, linking this modification not only to DNA damage persistence but also potentially to replication stalling caused by specific DNA lesions. Our results are consistent with proposed metabolic roles for WRN and genomic instability phenotypes associated with WRN deficiency. PMID:24965941

  1. [Research conducted at the Stefan S. Nicolau Institute of Virology of Bucharest in the area of nucleic acids and genetic engineering].

    PubMed

    Popa, L M; Repanovici, R; Iliescu, R

    1989-01-01

    A brief review is done of some of the most important studies realised by the "Stefan S. Nicolau" Institute researchers in the field of nucleic acids. It is worth mentioning among these the investigations about interactions between nucleic acids and some biologically active substances, the recombinant DNA, as well as the most recent works on DNA-DNA hybridization in the avidine-biotine system. PMID:2699967

  2. The color of complexes and UV-vis spectroscopy as an analytical tool of Alfred Werner's group at the University of Zurich.

    PubMed

    Fox, Thomas; Berke, Heinz

    2014-01-01

    Two PhD theses (Alexander Gordienko, 1912; Johannes Angerstein, 1914) and a dissertation in partial fulfillment of a PhD thesis (H. S. French, Zurich, 1914) are reviewed that deal with hitherto unpublished UV-vis spectroscopy work of coordination compounds in the group of Alfred Werner. The method of measurement of UV-vis spectra at Alfred Werner's time is described in detail. Examples of spectra of complexes are given, which were partly interpreted in terms of structure (cis ↔ trans configuration, counting number of bands for structural relationships, and shift of general spectral features by consecutive replacement of ligands). A more complete interpretation of spectra was hampered at Alfred Werner's time by the lack of a light absorption theory and a correct theory of electron excitation, and the lack of a ligand field theory for coordination compounds. The experimentally difficult data acquisitions and the difficult spectral interpretations might have been reasons why this method did not experience a breakthrough in Alfred Werner's group to play a more prominent role as an important analytical method. Nevertheless the application of UV-vis spectroscopy on coordination compounds was unique and novel, and witnesses Alfred Werner's great aptitude and keenness to always try and go beyond conventional practice. PMID:24983805

  3. Modeling mass transfer in solid oxide fuel cell anode: I. Comparison between Fickian, Stefan-Maxwell and dusty-gas models

    NASA Astrophysics Data System (ADS)

    Bao, Cheng; Jiang, Zeyi; Zhang, Xinxin

    2016-04-01

    Fickian, Stefan-Maxwell and dusty-gas model have been widely used in modeling mass transfer in porous electrodes of solid oxide fuel cells. Suwanwarangkul et al. (J. Power Sources 122 (2003) 9-18) implement a survey for performance comparison among these models to predict the concentration overpotential of a solid oxide fuel cell anode. In their work, the flux ratio of species is calculated by Graham's law and contradictorily the equimolar counter transport is used for isobaric assumption. Focused on the flux-ratio approaches and usually neglected pressure gradient, a comparison between Fickian, Stefan-Maxwell and dusty-gas model is done again in this article. The dusty gas model combined with the 'Stoich' flux-ratio approach, i.e. the species flux is dictated by its stoichiometry of the electrochemical reaction, is validated to make the best performance. And all models by the 'Graham' flux-ratio approach, i.e. the flux of species satisfies Graham's law, underestimate the concentration overpotential when the molecular weights of species are quite different. The extended Stefan-Maxwell model is an alternative, although it generally exaggerates the role of Knudsen diffusion. The effect of pore size on the Knudsen diffusion and pressure gradient is also discussed.

  4. The 2009 Lindau Nobel Laureate Meeting: Werner Arber, Physiology or Medicine 1978

    PubMed Central

    Arber, Werner

    2010-01-01

    Swiss microbial geneticist, Werner Arber shared the 1978 Nobel Prize in Physiology or Medicine with Hamilton Smith and Daniel Nathans for their discovery of restriction endonucleases. Werner Arber was born in Granichen, Switzerland in 1929. Following a public school education, he entered the Swiss Polytechnical School in Zurich in 1949, working toward a diploma in natural sciences. There, his first research experience involved isolating and characterizing an isomer of chlorine. Following graduation in 1953, Arber joined a graduate program at the University of Geneva, taking on an assistanceship in electron microscopy (EM), in which he studied gene transfer in the bacterial virus (bacteriophage) lambda. Eventually encountering limitations with EM as a tool, he began using microbial genetics as a methodology for his studies. The study of microbial genetics had been possible for a relatively short time: DNA had been discovered to carry genetic information only a decade before he d entered the field. After earning his Ph.D. in 1958, Arber continued to develop skills in microbial genetics, working with colleagues in the United States for a short time before returning to Geneva at beginning of 1960. There, he continued working on lambda transduction in E. coli, but found that the virus would not efficiently propagate. Recalling research done seven years earlier by Joe Bertani and Jean Weigle on "host-controlled restriction-modification", he realized there must be a host-controlled modification of the invading DNA, and sought to identify the mechanism. Based on Grete Kallengerger s work that demonstrated degradation of both irradiated and non-irradiated phage lambda following injection in a host, Arber and his graduate student, Daisy Dussoix further investigated the fate of DNA, and found that restriction and modification (later determined to be postreplicative nuclotide methylation) directly affected DNA, but did not cause mutations. They also found that theses were

  5. The 2009 Lindau Nobel Laureate Meeting: Werner Arber, physiology or medicine 1978.

    PubMed

    Arber, Werner

    2010-01-01

    Swiss microbial geneticist, Werner Arber shared the 1978 Nobel Prize in Physiology or Medicine with Hamilton Smith and Daniel Nathans for their discovery of restriction endonucleases. Werner Arber was born in Granichen, Switzerland in 1929. Following a public school education, he entered the Swiss Polytechnical School in Zurich in 1949, working toward a diploma in natural sciences. There, his first research experience involved isolating and characterizing an isomer of chlorine. Following graduation in 1953, Arber joined a graduate program at the University of Geneva, taking on an assistanceship in electron microscopy (EM), in which he studied gene transfer in the bacterial virus (bacteriophage) lambda. Eventually encountering limitations with EM as a tool, he began using microbial genetics as a methodology for his studies. The study of microbial genetics had been possible for a relatively short time: DNA had been discovered to carry genetic information only a decade before he d entered the field. After earning his Ph.D. in 1958, Arber continued to develop skills in microbial genetics, working with colleagues in the United States for a short time before returning to Geneva at beginning of 1960. There, he continued working on lambda transduction in E. coli, but found that the virus would not efficiently propagate. Recalling research done seven years earlier by Joe Bertani and Jean Weigle on "host-controlled restriction-modification", he realized there must be a host-controlled modification of the invading DNA, and sought to identify the mechanism. Based on Grete Kallengerger s work that demonstrated degradation of both irradiated and non-irradiated phage lambda following injection in a host, Arber and his graduate student, Daisy Dussoix further investigated the fate of DNA, and found that restriction and modification (later determined to be postreplicative nuclotide methylation) directly affected DNA, but did not cause mutations. They also found that theses were

  6. The role of the Stefan-Boltzmann law in the thermodynamic optimization of an n-Müser engine

    NASA Astrophysics Data System (ADS)

    Ramírez-Moreno, M. A.; González-Hernández, S.; Angulo-Brown, F.

    2016-02-01

    A Müser-type engine model can be taken as a particular case of a Curzon-Ahlborn thermal cycle, when the upper thermal conductance is finite and the lower one is infinite. In addition, the upper heat exchange is given by the Stefan-Boltzmann law. That model is suitable to thermodynamically describe some aspects of energy converters as solar cells and photosynthetic systems. In the present article, we call n-Müser engine to an engine of the Müser type in which the T4 heat transfer law is substituted by a Tn-law, being n > 0 a real number. Here, we show that if we use the so-called ecological criterion of merit to optimize finite-time heat engines to compare the thermodynamic performance of the n-Müser engines under approximate terrestrial conditions (see below), we obtain that n = 4 accomplishes the best performance. This same result was obtained by using data from the rest of planets of the solar system.

  7. Multicomponent diffusion in molten salt LiF-BeF2: Dynamical correlations and Maxwell-Stefan diffusivities

    NASA Astrophysics Data System (ADS)

    Chakraborty, Brahmananda; Ramaniah, Lavanya M.

    2015-06-01

    Applying Green-Kubo formalism and equilibrium molecular dynamics (MD) simulations, we have studied the dynamic correlation, Onsager coeeficients and Maxwell-Stefan (MS) Diffusivities of molten salt LiF-BeF2, which is used as coolant in high temperature reactor. All the diffusive flux correlations show back-scattering or cage dynamics which becomes pronouced at higher temperature. Although the MS diffusivities are expected to depend very lightly on the composition due to decoupling of thermodynamic factor, the diffusivity ĐLi-F and ĐBe-F decreases sharply for higher concentration of LiF and BeF2 respectively. Interestingly, all three MS diffusivities have highest magnitude for eutectic mixture at 1000K (except ĐBe-F at lower LiF mole fraction) which is desirable from coolant point of view. Although the diffusivity for positive-positive ion pair is negative it is not in violation of the second law of thermodynamics as it satisfies the non-negative entropic constraints.

  8. Continuum Model for Decontamination of Chemical Warfare Agent from a Rubbery Polymer using the Maxwell-Stefan Formulation

    NASA Astrophysics Data System (ADS)

    Varady, Mark; Bringuier, Stefan; Pearl, Thomas; Stevenson, Shawn; Mantooth, Brent

    Decontamination of polymers exposed to chemical warfare agents (CWA) often proceeds by application of a liquid solution. Absorption of some decontaminant components proceed concurrently with extraction of the CWA, resulting in multicomponent diffusion in the polymer. In this work, the Maxwell-Stefan equations were used with the Flory-Huggins model of species activity to mathematically describe the transport of two species within a polymer. This model was used to predict the extraction of the nerve agent O-ethyl S-[2(diisopropylamino)ethyl] methylphosphonothioate (VX) from a silicone elastomer into both water and methanol. Comparisons with experimental results show good agreement with minimal fitting of model parameters from pure component uptake data. Reaction of the extracted VX with sodium hydroxide in the liquid-phase was also modeled and used to predict the overall rate of destruction of VX. Although the reaction proceeds more slowly in the methanol-based solution compared to the aqueous solution, the extraction rate is faster due to increasing VX mobility as methanol absorbs into the silicone, resulting in an overall faster rate of VX destruction.

  9. Multicomponent diffusion in molten salt LiF-BeF{sub 2}: Dynamical correlations and Maxwell–Stefan diffusivities

    SciTech Connect

    Chakraborty, Brahmananda Ramaniah, Lavanya M.

    2015-06-24

    Applying Green–Kubo formalism and equilibrium molecular dynamics (MD) simulations, we have studied the dynamic correlation, Onsager coeeficients and Maxwell–Stefan (MS) Diffusivities of molten salt LiF-BeF{sub 2}, which is used as coolant in high temperature reactor. All the diffusive flux correlations show back-scattering or cage dynamics which becomes pronouced at higher temperature. Although the MS diffusivities are expected to depend very lightly on the composition due to decoupling of thermodynamic factor, the diffusivity Đ{sub Li-F} and Đ{sub Be-F} decreases sharply for higher concentration of LiF and BeF{sub 2} respectively. Interestingly, all three MS diffusivities have highest magnitude for eutectic mixture at 1000K (except Đ{sub Be-F} at lower LiF mole fraction) which is desirable from coolant point of view. Although the diffusivity for positive-positive ion pair is negative it is not in violation of the second law of thermodynamics as it satisfies the non-negative entropic constraints.

  10. Maxwell-Stefan diffusion and dynamical correlation in molten LiF-KF: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Jain, Richa Naja; Chakraborty, Brahmananda; Ramaniah, Lavanya M.

    2016-05-01

    In this work our main objective is to compute Dynamical correlations, Onsager coefficients and Maxwell-Stefan (MS) diffusivities for molten salt LiF-KF mixture at various thermodynamic states through Green-Kubo formalism for the first time. The equilibrium molecular dynamics (MD) simulations were performed using BHM potential for LiF-KF mixture. The velocity autocorrelations functions involving Li ions reflect the endurance of cage dynamics or backscattering with temperature. The magnitude of Onsager coefficients for all pairs increases with increase in temperature. Interestingly most of the Onsager coefficients has almost maximum magnitude at the eutectic composition indicating the most dynamic character of the eutectic mixture. MS diffusivity hence diffusion for all ion pairs increases in the system with increasing temperature. Smooth variation of the diffusivity values denies any network formation in the mixture. Also, the striking feature is the noticeable concentration dependence of MS diffusivity between cation-cation pair, ĐLi-K which remains negative for most of the concentration range but changes sign to become positive for higher LiF concentration. The negative MS diffusivity is acceptable as it satisfies the non-negative entropy constraint governed by 2nd law of thermodynamics. This high diffusivity also vouches the candidature of molten salt as a coolant.

  11. Turnover of sulfated glycosaminoglycans in fibroblasts derived from patients with Werner's syndrome

    SciTech Connect

    Cowles, E.A.; Brauker, J.H.; Anderson, R.L.

    1987-02-01

    Fibroblasts derived from patients with Werner's syndrome (WS) were incubated with radioactive sulfate to study the incorporation of 35S into glycosaminoglycans (GAGs). The accumulation of cell-associated 35S radioactivity in the GAGs of WS fibroblasts was consistently higher than parallel accumulation in normal human fibroblasts, but was substantially less than in fibroblasts derived from patients with Hurler's syndrome (HS). However, when fibroblasts were labeled with 35SO4(2-), trypsinized to remove extracellular and pericellular radioactive GAGs, replated, and chased to follow the fate of the intracellular radioactivity, both WS and normal cells showed a rapid release of the intracellular 35S, while HS cells showed little or no loss of intracellular radioactivity. The radioactivity released from WS and normal cells was of low molecular weight (LMW), eluting from gel filtration columns at the same position as free sulfate. These results establish that WS cells degrade intracellular sulfated GAGs and argue against the hypothesis that a defect in GAG degradation pathways is the basis for the increased level of cell-associated GAGs. Other possible explanations for the increased cell-associated (35S)GAGs in WS cells as compared with normal cells were also considered: increased GAG sulfation; an increase in GAG chain length; an increased rate of GAG synthesis; and a decreased rate of shedding of cell surface proteoglycan into the medium. No difference between normal and WS fibroblasts in any of the above parameters was observed. These results strongly imply that the primary biochemical defect in WS fibroblasts does not involve sulfated GAG metabolism.

  12. Narrowing the position of the Werner syndrome locus by homozygosity analysis - extension of homozygosity analysis

    SciTech Connect

    Nakura, Jun; Miki, Tetsuro; Ye, Lin

    1996-08-15

    Werner syndrome (WS) is an autosomal recessive disorder characterized by the premature occurrence of many age-related features. Previously, the WS gene (WRN) was mapped between D8S131 and D8S87, in an 8.3-cM interval. In this study, regions of homozygosity in 36 WS patients from inbred families were searched for by genotyping for 35 dinucleotide repeat polymorphic markers to narrow down the W-RN critical region. The region most consistently homozygous in these patients was between the D8S1219/D8S1220 cluster and D8S278, within a 4.4-cM interval. For 16 markers mapped in this interval, 24 WS patients (22 Japanese patients and 2 Caucasian patients) in whom consanguinity failed to be proved were also genotyped, under the assumption that some of these patients might still be from consanguineous marriages. The data were analyzed by Fisher`s exact test with a 2 x 2 contingency table for the 22 Japanese patients, excluding the 2 Caucasian patients. The frequencies of homozygosity in the 22 patients at 10 of 16 markers tested were significantly higher than those detected in the general population. Analysis of homozygosity patterns indicated that the region most consistently homozygous was between D8S1445 and D8S278. Thus the WRN locus is most likely between the two markers D8S1445 and D8S278, in a 1.6-cM interval. 49 refs., 4 tabs.

  13. Inflammageing assessed by MMP9 in normal Japanese individuals and the patients with Werner syndrome

    PubMed Central

    Goto, Makoto; Chiba, Junji; Matsuura, Masaaki; Iwaki-Egawa, Sachiko; Watanabe, Yasuhiro

    2016-01-01

    Summary Age-associated minor inflammation: inflammageing may explain human ageing mechanism(s). Our previous study reported a significant increase in the serum level of highly sensitive C-reactive protein (hsCRP) with normal ageing and the patients with Werner syndrome (WS). To further study the minor inflammatory condition associated with ageing, another possible ageing biomarker: matrix metalloproteinase-9 (MMP9) was examined in the sera from 217 normal Japanese individuals aged between 1 and 100 years and 41 mutation-proven Japanese WS aged between 32 and 70 years. MMP9 was assayed by ELISA. The serum level of MMP9 was elevated significantly (p < 0.001) with normal ageing from both sexes as hsCRP. In contrast to normal ageing, the serum MMP9 level in WS decreased significantly with calendar age (p < 0.05). The MMP9 level (ng/mL) in WS (147.2 ± 28.5) was not significantly different in comparison with those from age-matched normal adult population aged between 25 and 70 years (109.1 ± 9.4), nor normal elderly population aged between 71 and 100 years (179.9 ± 16.1). Although both normal ageing and WS were associated with minor inflammation, the inflammatory parameters such as serum MMP9 and hsCRP changed differently between normal ageing and WS. The WS-specific chronic inflammation including skin ulcer and diabetes mellitus may contribute the different behavior of both ageing biomarkers from normal ageing. PMID:27195193

  14. Mutations in the consensus helicase domains of the Werner syndrome gene

    SciTech Connect

    Yu, Chang-En; Oshima, Junko; Wijsman, E.M.

    1997-02-01

    Werner syndrome (WS) is an autosomal recessive disease with a complex phenotype that is suggestive of accelerated aging. WS is caused by mutations in a gene, WRN, that encodes a predicted 1,432-amino-acid protein with homology to DNA and RNA helicases. Previous work identified four WS mutations in the 3{prime} end of the gene, which resulted in predicted truncated protein products of 1,060-1,247 amino acids but did not disrupt the helicase domain region (amino acids 569-859). Here, additional WS subjects were screened for mutations, and the intron-exon structure of the gene was determined. A total of 35 exons were defined, with the coding sequences beginning in the second exon. Five new WS mutations were identified: two nonsense mutations at codons 369 and 889; a mutation at a splice-junction site, resulting in a predicted truncated protein of 760 amino acids; a 1-bp deletion causing a frameshift; and a predicted truncated protein of 391 amino acids. Another deletion is >15 kb of genomic DNA, including exons 19-23; the predicted protein is 1,186 amino acids long. Four of these new mutations either partially disrupt the helicase domain region or result in predicted protein products completely missing the helicase region. These results confirm that mutations in the WRN gene are responsible for WS. Also, the location of the mutations indicates that the presence or absence of the helicase domain does not influence the WS phenotype and suggests that WS is the result of complete loss of function of the WRN gene product. 63 refs., 1 fig., 5 tabs.

  15. The role of cellular senescence in Werner syndrome: toward therapeutic intervention in human premature aging.

    PubMed

    Davis, Terence; Wyllie, Fiona S; Rokicki, Michal J; Bagley, Mark C; Kipling, David

    2007-04-01

    Werner syndrome (WS) is a premature aging disorder used as a model of normal human aging. WS individuals have several characteristics of normal aging, such as cataracts, hair graying, and skin aging, but manifest these at an early age. Additionally, WS individuals have high levels of inflammatory diseases, such as atherosclerosis and type 2 diabetes. The in vivo aging in WS is associated with accelerated aging of fibroblasts in culture. The cause of the accelerated senescence is not understood, but may be due to the genomic instability that is a hallmark of WS. Genome instability results in activation of stress kinases, such as p38, and the p38-specific inhibitor SB203580, prevents the accelerated senescence seen in WS fibroblasts. However, oxidative damage plays a role, as low oxygen conditions and antioxidant treatment revert some of the accelerated senescence phenotype. The effects of oxidative stress appear to be suppressible by SB203580; however, it does not appear to be transduced by p38. As SB203580 is known to inhibit other kinases in addition to p38, this suggests that more than one kinase pathway is involved. The recent development of p38 inhibitors with different binding properties, specificities, and oral bioavailability, and of new potent and selective inhibitors of JNK and MK2, will make it possible to dissect the roles of various kinase pathways in the accelerated senescence of WS cells. If this accelerated senescence is reflective of WS aging in vivo, these kinase inhibitors may well form the basis of antiaging therapies for individuals with WS.

  16. GENERAL: Entanglement for Two-Qubit Extended Werner-Like States: Effect of Non-Markovian Environments

    NASA Astrophysics Data System (ADS)

    Shan, Chuan-Jia; Liu, Ji-Bing; Chen, Tao; Chen, Wei-Wen; Liu, Tang-Kun; Huang, Yan-Xia; Li, Hong

    2010-09-01

    We investigate the sudden birth and sudden death of entanglement of two qubits interacting with un-correlated structured reservoirs. The system is initially prepared in two-qubit extended Werner-like state. We work out the dependence of the entanglement dynamics on both non-Markovian environments and the purity of initial state, and show that non-Markovian environments and the purity can control the time of the two-qubit entanglement sudden death and the reservoirs' entanglement sudden birth. Furthermore, under the conditions of different purity and initial entanglement, the revival of qubits' entanglement can manifest before, simultaneously or even after the disentanglement of their corresponding reservoirs.

  17. Diverse gene sequences are overexpressed in werner syndrome fibroblasts undergoing premature replicative senescence.

    PubMed Central

    Murano, S; Thweatt, R; Shmookler Reis, R J; Jones, R A; Moerman, E J; Goldstein, S

    1991-01-01

    Genes that play a role in the senescent arrest of cellular replication are likely to be overexpressed in human diploid fibroblasts (HDF) derived from subjects with Werner syndrome (WS) because these cells have a severely curtailed replicative life span. To identify some of these genes, a cDNA library was constructed from WS HDF after they had been serum depleted and repleted (5 days in medium containing 1% serum followed by 24 h in medium containing 20% serum). Differential screening of 7,500 colonies revealed 102 clones that hybridized preferentially with [32P]cDNA derived from RNA of WS cells compared with [32P]cDNA derived from normal HDF. Cross-hybridization and partial DNA sequence determination identified 18 independent gene sequences, 9 of them known and 9 unknown. The known genes included alpha 1(I) procollagen, alpha 2(I) procollagen, fibronectin, ferritin heavy chain, insulinlike growth factor-binding protein-3 (IGFBP-3), osteonectin, human tissue plasminogen activator inhibitor type I, thrombospondin, and alpha B-crystallin. The nine unknown clones included two novel gene sequences and seven additional sequences that contained both novel segments and the Alu class of repetitive short interspersed nuclear elements; five of these seven Alu+ clones also contained the long interpersed nuclear element I (KpnI) family of repetitive elements. Northern (RNA) analysis, using the 18 sequences as probes, showed higher levels of these mRNAs in WS HDF than in normal HDF. Five selected mRNAs studied in greater detail [alpha 1(I) procollagen, fibronectin, insulinlike growth factor-binding protein-3, WS3-10, and WS9-14] showed higher mRNA levels in both WS and late-passage normal HDF than in early-passage normal HDF at various intervals following serum depletion/repletion and after subculture and growth from sparse to high-density confluent arrest. These results indicate that senescence of both WS and normal HDF is accompanied by overexpression of similar sets of

  18. Influence of Dzyaloshinshkii-Moriya interaction on quantum correlations in two-qubit Werner states and MEMS

    NASA Astrophysics Data System (ADS)

    Sharma, Kapil K.; Pandey, S. N.

    2015-04-01

    In this paper, we study the influence of Dzyaloshinskii-Moriya (DM) interaction on quantum correlations in two-qubit Werner states and maximally entangled mixed states (MEMS). We consider our system as a closed system of a qubit pair and one auxiliary qubit, which interact with any one of the qubit of the pair through DM interaction. We show that DM interaction, taken along any direction ( x or y or z), does not affect two-qubit Werner states. On the other hand, the MEMS are affected by x and z components of DM interaction and remain unaffected by the y component. Further, we find that the state (i.e., probability amplitude) of auxiliary qubit does not affect the quantum correlations in both the states, and only DM interaction strength influences the quantum correlations. So one can avoid the intention to prepare the specific state of auxiliary qubit to manipulate the quantum correlations in both the states. We mention here that avoiding the preparation of state can contribute to cost reduction in quantum information processing. We also observe the phenomenon of entanglement sudden death in the present study.

  19. Sudden birth versus sudden death of entanglement for the extended Werner-like state in a dissipative environment

    NASA Astrophysics Data System (ADS)

    Shan, Chuan-Jia; Chen, Tao; Liu, Ji-Bing; Cheng, Wei-Wen; Liu, Tang-Kun; Huang, Yan-Xia; Li, Hong

    2010-06-01

    In this paper, we investigate the dynamical behaviour of entanglement in terms of concurrence in a bipartite system subjected to an external magnetic field under the action of dissipative environments in the extended Werner-like initial state. The interesting phenomenon of entanglement sudden death as well as sudden birth appears during the evolution process. We analyse in detail the effect of the purity of the initial entangled state of two qubits via Heisenberg XY interaction on the apparition time of entanglement sudden death and entanglement sudden birth. Furthermore, the conditions on the conversion of entanglement sudden death and entanglement sudden birth can be generalized when the initial entangled state is not pure. In particular, a critical purity of the initial mixed entangled state exists, above which entanglement sudden birth vanishes while entanglement sudden death appears. It is also noticed that stable entanglement, which is independent of different initial states of the qubits (pure or mixed state), occurs even in the presence of decoherence. These results arising from the combination of the extended Werner-like initial state and dissipative environments suggest an approach to control and enhance the entanglement even after purity induced sudden birth, death and revival.

  20. Downregulation of the Werner syndrome protein induces a metabolic shift that compromises redox homeostasis and limits proliferation of cancer cells.

    PubMed

    Li, Baomin; Iglesias-Pedraz, Juan Manuel; Chen, Leng-Ying; Yin, Fei; Cadenas, Enrique; Reddy, Sita; Comai, Lucio

    2014-04-01

    The Werner syndrome protein (WRN) is a nuclear protein required for cell growth and proliferation. Loss-of-function mutations in the Werner syndrome gene are associated with the premature onset of age-related diseases. How loss of WRN limits cell proliferation and induces replicative senescence is poorly understood. Here, we show that WRN depletion leads to a striking metabolic shift that coordinately weakens the pathways that generate reducing equivalents for detoxification of reactive oxygen species and increases mitochondrial respiration. In cancer cells, this metabolic shift counteracts the Warburg effect, a defining characteristic of many malignant cells, resulting in altered redox balance and accumulation of oxidative DNA damage that inhibits cell proliferation and induces a senescence-like phenotype. Consistent with these findings, supplementation with antioxidant rescues at least in part cell proliferation and decreases senescence in WRN-knockdown cancer cells. These results demonstrate that WRN plays a critical role in cancer cell proliferation by contributing to the Warburg effect and preventing metabolic stress.

  1. Maxwell-Stefan diffusivities in binary mixtures of ionic liquids with dimethyl sulfoxide (DMSO) and H2O.

    PubMed

    Liu, Xin; Vlugt, Thijs J H; Bardow, André

    2011-07-01

    Ionic liquids (ILs) are promising solvents for applications ranging from CO2 capture to the pretreatment of biomass. However, slow diffusion often restricts their applicability. A thorough understanding of diffusion in ILs is therefore highly desirable. Previous research largely focused on self-diffusion in ILs. For practical applications, mutual diffusion is by far more important than self-diffusion. For describing mutual diffusion in multicomponent systems, the Maxwell-Stefan (MS) approach is commonly used. Unfortunately, it is difficult to obtain MS diffusivities from experiments, but they can be directly extracted from molecular dynamics (MD) simulations. In this work, MS diffusivities were computed in binary systems containing 1-alkyl-3-methylimidazolium chloride (C(n)mimCl, n = 2, 4, 8), water, and/or dimethyl sulfoxide (DMSO) using MD. The dependence of self- and MS diffusivities on mixture composition was investigated. Our results show the following: (1) For solutions of ILs in water and DMSO, self-diffusivities decrease strongly with increasing IL concentration. For DMSO-IL, a single exponential decay is observed. (2) In both water-IL and DMSO-IL, MS diffusivities vary by a factor of 10 within the concentration range which is, however, still significantly smaller than the variation of the self-diffusion coefficients. (3) The MS diffusivities of the IL are almost independent of the alkyl chain length. (4) ILs stay in a form of isolated ions in C(n)mimCl-H2O mixtures; however, dissociation into ions is much less observed in C(n)mimCl-DMSO systems. This has a large effect on the concentration dependence of MS diffusivities. (5) Recently, we proposed a new model for predicting the MS diffusivity at infinite dilution, that is, Đ(ij)(x(k-->)1) (Ind. Eng. Chem. Res. 2011, 50, 4776-4782). This quantity describes the friction between components i and j when both are infinitely diluted in component k. In contrast to earlier empirical models, our model is based on

  2. A novel Werner Syndrome mutation: pharmacological treatment by read-through of nonsense mutations and epigenetic therapies

    PubMed Central

    Agrelo, Ruben; Sutz, Miguel Arocena; Setien, Fernando; Aldunate, Fabian; Esteller, Manel; Da Costa, Valeria; Achenbach, Ricardo

    2015-01-01

    Werner Syndrome (WS) is a rare inherited disease characterized by premature aging and increased propensity for cancer. Mutations in the WRN gene can be of several types, including nonsense mutations, leading to a truncated protein form. WRN is a RecQ family member with both helicase and exonuclease activities, and it participates in several cell metabolic pathways, including DNA replication, DNA repair, and telomere maintenance. Here, we reported a novel homozygous WS mutation (c.3767 C > G) in 2 Argentinian brothers, which resulted in a stop codon and a truncated protein (p.S1256X). We also observed increased WRN promoter methylation in the cells of patients and decreased messenger WRN RNA (WRN mRNA) expression. Finally, we showed that the read-through of nonsense mutation pharmacologic treatment with both aminoglycosides (AGs) and ataluren (PTC-124) in these cells restores full-length protein expression and WRN functionality. PMID:25830902

  3. The real identity of Leptodiranycthemera Werner, 1901 from Ecuador: a junior synonym of Oxyrhopuspetolarius (Linnaeus, 1758) (Serpentes, Dipsadidae).

    PubMed

    Costa, João Carlos Lopes; Kucharzewski, Christoph; Prudente, Ana Lúcia da Costa

    2015-01-01

    Leptodiranycthemera Werner, 1901, was described from a specimen collected in Ecuador. No information on the holotype was published after its description. In the most recent review of Leptodeira, Leptodiranycthemera was considered to be a synonym of Leptodeiraannulataannulata, although the author emphasized that the holotype was lost and did not include the pholidotic data from the original description in his account of Leptodeiraannulataannulata. Since this review, a number of authors have accepted this synonymy. Recently, analyzing specimens of Leptodeira in the Museum für Naturkunde, Berlin, Germany, we discovered the holotype of Leptodiranycthemera. This holotype is re-described here, and its correct identity is determined. Based on the analysis of meristic characters and the color of the holotype, we recognize Leptodiranycthemera as a junior synonym of Oxyrhopuspetolarius.

  4. Werner syndrome protein: functions in the response to DNA damage and replication stress in S-phase.

    PubMed

    Cheng, Wen-Hsing; Muftuoglu, Meltem; Bohr, Vilhelm A

    2007-09-01

    Werner syndrome (WS) is an excellent model system for the study of human aging. WRN, a nuclear protein mutated in WS, plays multiple roles in DNA metabolism. Our understanding about the metabolic regulation and function of this RecQ helicase has advanced greatly during the past decade, largely due to the availability of purified WRN protein, WRN knockdown cells, and WRN knockout mice. Recent biochemical and genetic studies indicate that WRN plays significant roles in DNA replication, DNA repair, and telomere maintenance. Interestingly, many WRN functions require handling of DNA ends during S-phase, and evidence suggests that WRN plays both upstream and downstream roles in the response to DNA damage. Future research should focus on the mechanism(s) of WRN in the regulation of the various DNA metabolism pathways and development of therapeutic approaches to treat premature aging syndromes such as WS.

  5. Quantum discord with weak measurement operators of quasi-Werner states based on bipartite entangled coherent states

    NASA Astrophysics Data System (ADS)

    Castro, E.; Gómez, R.; Ladera, C. L.; Zambrano, A.

    2013-11-01

    Among many applications quantum weak measurements have been shown to be important in exploring fundamental physics issues, such as the experimental violation of the Heisenberg uncertainty relation and the Hardy paradox, and have also technological implications in quantum optics, quantum metrology and quantum communications, where the precision of the measurement is as important as the precision of quantum state preparation. The theory of weak measurement can be formulated using the pre-and post-selected quantum systems, as well as using the weak measurement operator formalism. In this work, we study the quantum discord (QD) of quasi-Werner mixed states based on bipartite entangled coherent states using the weak measurements operator, instead of the projective measurement operators. We then compare the quantum discord for both kinds of measurement operators, in terms of the entanglement quality, the latter being measured using the concept of concurrence. It's found greater quantum correlations using the weak measurement operators.

  6. GENERAL: Thermal entanglement and teleportation of a thermally mixed entangled state of a Heisenberg chain through a Werner state

    NASA Astrophysics Data System (ADS)

    Huang, Li-Yuan; Fang, Mao-Fa

    2008-07-01

    The thermal entanglement and teleportation of a thermally mixed entangled state of a two-qubit Heisenberg XXX chain under the Dzyaloshinski-Moriya (DM) anisotropic antisymmetric interaction through a noisy quantum channel given by a Werner state is investigated. The dependences of the thermal entanglement of the teleported state on the DM coupling constant, the temperature and the entanglement of the noisy quantum channel are studied in detail for both the ferromagnetic and the antiferromagnetic cases. The result shows that a minimum entanglement of the noisy quantum channel must be provided in order to realize the entanglement teleportation. The values of fidelity of the teleported state are also studied for these two cases. It is found that under certain conditions, we can transfer an initial state with a better fidelity than that for any classical communication protocol.

  7. Genetic association between chromosome 8 microsatellite (MS8-134) and Werner syndrome (WRN): Chromosome microdissection and homozygosity mapping

    SciTech Connect

    Ye, Lin; Nakura, Jun; Mitsuda, Noriaki; Miki, Tetsuro

    1995-08-10

    Werner syndrome (WRN) is an autosomal recessive disorder characterized by premature aging that has been mapped to the short arm of chromosome 8, 8p11.2-p12. To refine the genetic map around the WRN region, we have isolated eight microsatellites for this region from a microdissection library. We typed members of Japanese families with WRN on the basis of homozygosity mapping analysis. There was no obligate recombination between the WRN locus and microsatellite clone, MS8-134 (D8S1055). The maximum lod score was 20.28 at {theta} = 0.00. Alleles for MS8-134 showed association with WRN in a case-control study (OR = 3.55, 95% CI 1.56-8.07, P < 0.01). Such microsatellites from a microdissection library of the definite chromosome region may be useful for positional cloning of the WRN gene. 23 refs., 1 figs., 1 tab.

  8. Aging stem cells. A Werner syndrome stem cell model unveils heterochromatin alterations as a driver of human aging.

    PubMed

    Zhang, Weiqi; Li, Jingyi; Suzuki, Keiichiro; Qu, Jing; Wang, Ping; Zhou, Junzhi; Liu, Xiaomeng; Ren, Ruotong; Xu, Xiuling; Ocampo, Alejandro; Yuan, Tingting; Yang, Jiping; Li, Ying; Shi, Liang; Guan, Dee; Pan, Huize; Duan, Shunlei; Ding, Zhichao; Li, Mo; Yi, Fei; Bai, Ruijun; Wang, Yayu; Chen, Chang; Yang, Fuquan; Li, Xiaoyu; Wang, Zimei; Aizawa, Emi; Goebl, April; Soligalla, Rupa Devi; Reddy, Pradeep; Esteban, Concepcion Rodriguez; Tang, Fuchou; Liu, Guang-Hui; Belmonte, Juan Carlos Izpisua

    2015-06-01

    Werner syndrome (WS) is a premature aging disorder caused by WRN protein deficiency. Here, we report on the generation of a human WS model in human embryonic stem cells (ESCs). Differentiation of WRN-null ESCs to mesenchymal stem cells (MSCs) recapitulates features of premature cellular aging, a global loss of H3K9me3, and changes in heterochromatin architecture. We show that WRN associates with heterochromatin proteins SUV39H1 and HP1α and nuclear lamina-heterochromatin anchoring protein LAP2β. Targeted knock-in of catalytically inactive SUV39H1 in wild-type MSCs recapitulates accelerated cellular senescence, resembling WRN-deficient MSCs. Moreover, decrease in WRN and heterochromatin marks are detected in MSCs from older individuals. Our observations uncover a role for WRN in maintaining heterochromatin stability and highlight heterochromatin disorganization as a potential determinant of human aging.

  9. Microwave-Assisted Synthesis of a MK2 Inhibitor by Suzuki-Miyaura Coupling for Study in Werner Syndrome Cells

    PubMed Central

    Bagley, Mark C.; Baashen, Mohammed; Chuckowree, Irina; Dwyer, Jessica E.; Kipling, David; Davis, Terence

    2015-01-01

    Microwave-assisted Suzuki-Miyaura cross-coupling reactions have been employed towards the synthesis of three different MAPKAPK2 (MK2) inhibitors to study accelerated aging in Werner syndrome (WS) cells, including the cross-coupling of a 2-chloroquinoline with a 3-pyridinylboronic acid, the coupling of an aryl bromide with an indolylboronic acid and the reaction of a 3-amino-4-bromopyrazole with 4-carbamoylphenylboronic acid. In all of these processes, the Suzuki-Miyaura reaction was fast and relatively efficient using a palladium catalyst under microwave irradiation. The process was incorporated into a rapid 3-step microwave-assisted method for the synthesis of a MK2 inhibitor involving 3-aminopyrazole formation, pyrazole C-4 bromination using N-bromosuccinimide (NBS), and Suzuki-Miyaura cross-coupling of the pyrazolyl bromide with 4-carbamoylphenylboronic acid to give the target 4-arylpyrazole in 35% overall yield, suitable for study in WS cells. PMID:26046488

  10. The effect of RO3201195 and a pyrazolyl ketone P38 MAPK inhibitor library on the proliferation of Werner syndrome cells.

    PubMed

    Bagley, Mark C; Dwyer, Jessica E; Baashen, Mohammed; Dix, Matthew C; Murziani, Paola G S; Rokicki, Michal J; Kipling, David; Davis, Terence

    2016-01-21

    Microwave-assisted synthesis of the pyrazolyl ketone p38 MAPK inhibitor RO3201195 in 7 steps and 15% overall yield, and the comparison of its effect upon the proliferation of Werner Syndrome cells with a library of pyrazolyl ketones, strengthens the evidence that p38 MAPK inhibition plays a critical role in modulating premature cellular senescence in this progeroid syndrome and the reversal of accelerated ageing observed in vitro on treatment with SB203580. PMID:26611938

  11. The effect of RO3201195 and a pyrazolyl ketone P38 MAPK inhibitor library on the proliferation of Werner syndrome cells.

    PubMed

    Bagley, Mark C; Dwyer, Jessica E; Baashen, Mohammed; Dix, Matthew C; Murziani, Paola G S; Rokicki, Michal J; Kipling, David; Davis, Terence

    2016-01-21

    Microwave-assisted synthesis of the pyrazolyl ketone p38 MAPK inhibitor RO3201195 in 7 steps and 15% overall yield, and the comparison of its effect upon the proliferation of Werner Syndrome cells with a library of pyrazolyl ketones, strengthens the evidence that p38 MAPK inhibition plays a critical role in modulating premature cellular senescence in this progeroid syndrome and the reversal of accelerated ageing observed in vitro on treatment with SB203580.

  12. Evaluation of comparison and proficiency test results of gamma ray spectrometry at Jožef Stefan Institute from 1986 to 2014.

    PubMed

    Glavič-Cindro, Denis; Korun, Matjaž; Nečemer, Marijan; Vodenik, Branko; Zorko, Benjamin

    2016-03-01

    One of the best ways to demonstrate the performance and capabilities of testing laboratories is to participate successfully in different international comparison schemes and proficiency tests. The overview of all results of such schemes in the field of high resolution gamma-ray spectrometry where the Laboratory for Radioactivity Measurements (LMR) of the Jožef Stefan Institute (JSI), Slovenia, participated in years 1986-2014 is presented. Different schemes are compared, strong points and drawbacks of different providers and schemes regarding evaluation procedures, determination of reference values, reporting time, sets of radionuclides included in the samples and range of activities of different radionuclides are discussed. One of the main conclusions is that the comparison and proficiency test samples normally contain substantially larger activities than are usually detected in environmental samples. Therefore the capability of determination of activities close to detection limits is usually covered only by few schemes.

  13. A Werner syndrome protein homolog affects C. elegans development, growth rate, life span and sensitivity to DNA damage by acting at a DNA damage checkpoint.

    PubMed

    Lee, Se-Jin; Yook, Jong-Sung; Han, Sung Min; Koo, Hyeon-Sook

    2004-06-01

    A Werner syndrome protein homolog in C. elegans (WRN-1) was immunolocalized to the nuclei of germ cells, embryonic cells, and many other cells of larval and adult worms. When wrn-1 expression was inhibited by RNA interference (RNAi), a slight reduction in C. elegans life span was observed, with accompanying signs of premature aging, such as earlier accumulation of lipofuscin and tissue deterioration in the head. In addition, various developmental defects, including small, dumpy, ruptured, transparent body, growth arrest and bag of worms, were induced by RNAi. The frequency of these defects was accentuated by gamma-irradiation, implying that they were derived from spontaneous or induced DNA damage. wrn-1(RNAi) worms showed accelerated larval growth irrespective of gamma-irradiation, and pre-meiotic germ cells had an abnormal checkpoint response to DNA replication blockage. These observations suggest that WRN-1 acts as a checkpoint protein for DNA damage and replication blockage. This idea is also supported by an accelerated S phase in wrn-1(RNAi) embryonic cells. wrn-1(RNAi) phenotypes similar to those of Werner syndrome, such as premature aging and short stature, suggest wrn-1-deficient C. elegans as a useful model organism for Werner syndrome. PMID:15115755

  14. Sgs1, a Homologue of the Bloom's and Werner's Syndrome Genes, Is Required for Maintenance of Genome Stability in Saccharomyces Cerevisiae

    PubMed Central

    Watt, P. M.; Hickson, I. D.; Borts, R. H.; Louis, E. J.

    1996-01-01

    The Saccharomyces cerevisiae SGS1 gene is homologous to Escherichia coli RecQ and the human BLM and WRN proteins that are defective in the cancer-prone disorder Bloom's syndrome and the premature aging disorder Werner's syndrome, respectively. While recQ mutants are deficient in conjugational recombination and DNA repair, Bloom's syndrome cell lines show hyperrecombination. Bloom's and Werner's syndrome cell lines both exhibit chromosomal instability. sgs1Δ strains show mitotic hyperrecombination, as do Bloom's cells. This was manifested as an increase in the frequency of interchromosomal homologous recombination, intrachromosomal excision recombination, and ectopic recombination. Hyperrecombination was partially independent of both RAD52 and RAD1. Meiotic recombination was not increased in sgs1Δ mutants, although meiosis I chromosome missegregation has been shown to be elevated. sgs1Δ suppresses the slow growth of a top3Δ strain lacking topoisomerase III. Although there was an increase in subtelomeric Y' instability in sgs1Δ strains due to hyperrecombination, no evidence was found for an increase in the instability of terminal telomeric sequences in a top3Δ or a sgs1Δ strain. This contrasts with the telomere maintenance defects of Werner's patients. We conclude that the SGS1 gene product is involved in the maintenance of genome stability in S. cerevisiae. PMID:8913739

  15. Tycho Brahe - Instrumentenbauer und Meister der Beobachtungstechnik

    NASA Astrophysics Data System (ADS)

    Wolfschmidt, Gudrun

    Vor der Erfindung des Fernrohrs war der dänische Astronom Tycho Brahe (1546 - 1601) der bedeutendste beobachtende Astronom. Von seinem Observatorium Uraniborg auf der - damals dänischen - Insel Hven ist heute noch der Grundriß erkennbar, von Stjerneborg sind die Fundamente erhalten, die Kuppeln in den 1950er Jahren ergänzt. In der Astronomie-Ausstellung im Deutschen Museum gibt es ein Modell der Sternwarte Uraniborg und der zugehörigen Instrumente (Maßstab 1:10); das größere Modell wurde dem Technischen Museum in Malmö geschenkt. Die Instrumente, die er in den Observatorien Uraniborg und Stjerneborg benutzte, sind nicht erhalten. Aber es gibt gute Beschreibungen der Instrumente (Halbkreis, Quadranten, Sextanten, Armillarsphären, Triquetrum, Himmelsglobus) in seinem Buch Astronomiae instauratae mechanica (Wandsbek 1598). Eine Nachbildung des großen hölzernen Quadranten kann man im Runden Turm in Kopenhagen sehen. Zwei Sextanten, hergestellt für Tycho um 1600 von Jost Bürgi und Erasmus Habermel, gibt es noch im Nationalmuseum für Technik in Prag. Ähnlichkeiten von Tychos Instrumenten mit Groß-Instrumenten aus dem islamischen Kulturkreis sind auffällig. Tycho Brahes Meßgeräte markieren einen großen Fortschritt in der Entwicklung astronomischer Instrumente und Meßtechniken und bilden die Grundlage für den weiteren Fortschritt der Positionsastronomie und der damit verbundenen Tabellenwerke. Die Nachwirkungen sind bis ins 17. und 18. Jahrhundert nachweisbar.

  16. Linkage disequilibrium and haplotype studies of chromosome 8p 11. 1-21. 1 markers and Werner syndrome

    SciTech Connect

    Yu, Chang-En; Schellenberg, G.D.; Oshima, Junko; Martin, G.M.; Goddard, K.A.B.; Wijsman, E.M. ); Miki, Tetsuro; Nakura, Jun; Ogihara, Toshio ); Poot, M.; Hoehn, H. )

    1994-08-01

    Werner syndrome (WS) is an autosomal recessive disorder, characterized as a progeroid syndrome, previously mapped to the 8p 11.2-21.1 region. Because WS is so rare, and because many patients are from consanguineous marriages, fine localization of the gene by traditional meiotic mapping methods is unlikely to succeed. Here the authors present the results of a search for a region that exhibits linkage disequilibrium with the disorder, under the assumption that identification of such a region may provide an alternative method of narrowing down the location of WRN, the gene responsible for WS. They present allele frequencies in Japanese and Caucasian cases and controls for D8S137, D8S131, D8S87, D8S278, D8S259, D8S283, fibroblast growth factor receptor 1, ankyrin 1, D8S339, and two polymorphisms in glutathione reductase (GSR), covering [approximately] 16.5 cM in total. They show that three of the markers examined - D8S339 and both polymorphisms in the GSR locus - show strong statistically significant evidence of disequilibrium with WRN in the Japanese population but not in the Caucasian population. In addition, they show that a limited number of haplotypes are associated with the disease in both populations and that these haplotypes define clusters of apparently related haplotypes that may identify as many as eight or nine independent WRN mutations in these two populations. 36 refs., 1 fig., 4 tabs.

  17. The Direct Collapse of a Massive Black Hole Seed under the Influence of an Anisotropic Lyman-Werner Source

    NASA Astrophysics Data System (ADS)

    Regan, John A.; Johansson, Peter H.; Wise, John H.

    2014-11-01

    The direct collapse model of supermassive black hole seed formation requires that the gas cools predominantly via atomic hydrogen. To this end we simulate the effect of an anisotropic radiation source on the collapse of a halo at high redshift. The radiation source is placed at a distance of 3 kpc (physical) from the collapsing object and is set to emit monochromatically in the center of the Lyman-Werner (LW) band. The LW radiation emitted from the high redshift source is followed self-consistently using ray tracing techniques. Due to self-shielding, a small amount of H2 is able to form at the very center of the collapsing halo even under very strong LW radiation. Furthermore, we find that a radiation source, emitting >1054 (~ 103 J21) photons s-1, is required to cause the collapse of a clump of M ~ 105 M ⊙. The resulting accretion rate onto the collapsing object is ~0.25 M ⊙ yr-1. Our results display significant differences, compared to the isotropic radiation field case, in terms of the H2 fraction at an equivalent radius. These differences will significantly affect the dynamics of the collapse. With the inclusion of a strong anisotropic radiation source, the final mass of the collapsing object is found to be M ~ 105 M ⊙. This is consistent with predictions for the formation of a supermassive star or quasi-star leading to a supermassive black hole.

  18. Niels Bohr's discussions with Albert Einstein, Werner Heisenberg, and Erwin Schroedinger: the origins of the principles of uncertainty and complementarity

    SciTech Connect

    Mehra, J.

    1987-05-01

    In this paper, the main outlines of the discussions between Niels Bohr with Albert Einstein, Werner Heisenberg, and Erwin Schroedinger during 1920-1927 are treated. From the formulation of quantum mechanics in 1925-1926 and wave mechanics in 1926, there emerged Born's statistical interpretation of the wave function in summer 1926, and on the basis of the quantum mechanical transformation theory - formulated in fall 1926 by Dirac, London, and Jordan - Heisenberg formulated the uncertainty principle in early 1927. At the Volta Conference in Como in September 1927 and at the fifth Solvay Conference in Brussels the following month, Bohr publicly enunciated his complementarity principle, which had been developing in his mind for several years. The Bohr-Einstein discussions about the consistency and completeness of quantum mechanics and of physical theory as such - formally begun in October 1927 at the fifth Solvay Conference and carried on at the sixth Solvay Conference in October 1930 - were continued during the next decades. All these aspects are briefly summarized.

  19. Nature of the Levantine (eastern Mediterranean) crust from multiple-source Werner deconvolution of Bouguer gravity anomalies

    NASA Astrophysics Data System (ADS)

    Khair, Kamal; Tsokas, Gregory N.

    1999-11-01

    The nature of the Levantine (eastern Mediterranean) crust has been the subject of controversy for many years, revolving around two hypotheses: the continental crust hypothesis and the oceanic crust hypothesis. The proponents of the first hypothesis suggest that the Levantine (eastern Mediterranean) basin is characterized by a thick sedimentary succession overlying thinned crust of continental origin, through which a number of aborted Mesozoic rifts were etched. However, multiple-source Werner deconvolution (MSWD) estimates and other geophysical data, integrated with earlier geological and geophysical results, provide further support to the second hypothesis (oceanic crust) and lead to the following conclusions: (1) The depth to Moho ranges from about 20 km to about 28 km below sea level, with an average crustal thickness of about 22 km. (2) The large thickness (about 10 km) of Phanerozoic section leaves only about 12 km of thickness for the igneous/metamorphic (basement) complex. (3) The northern boundary of the Levantine (easternmost Mediterranean) lithosphere is delineated by an arcuate belt of seismic activities along the southern margin of Cyprus. (4) The formation of the Phoenician and Latakia basins and the Iskenderun Bay is probably controlled by the counterclockwise rotation of the lithospheric slices southeast of Cyprus. (5) The apparent absence of magnetic anomaly lineations (reversals) is due probably to the thick Phanerozoic cover, and/or the formation of the oceanic crust during a long magnetic chron.

  20. Cellular deficiency of Werner Syndrome protein or RECQ1 promotes genotoxic potential of hydroquinone and benzo[a]pyrene exposure

    PubMed Central

    Garige, Mamatha; Sharma, Sudha

    2014-01-01

    The five known RecQ helicases in humans (RECQ1, BLM, WRN, RECQL4, and RECQ5) have demonstrated roles in diverse genome maintenance mechanisms but their functions in safeguarding the genome from environmental toxicants are poorly understood. Here, we have evaluated a potential role of WRN (mutated in Werner Syndrome) and RECQ1 (the most abundant homolog of WRN) in hydroquinone and benzo[a]pyrene-induced genotoxicity. Silencing of WRN or RECQ1 expression in HeLa cells increased their sensitivity to hydroquinone and benzo[a]pyrene but elicited distinct DNA damage response. RECQ1-depleted cells exhibited increased RPA phosphorylation, Chk1 activation, and DNA double strand breaks as compared to control or WRN-depleted cells following exposure to benzo[a]pyrene treatment. Benzo[a]pyrene-induced double strand breaks in RECQ1-depleted cells were dependent on DNA-PK activity. Notably, loss of WRN in RECQ1-depleted cells ameliorated benzo[a]pyrene toxicity. Collectively, our results provide first indication of non-redundant participation of WRN and RECQ1 in protection from the potentially carcinogenic effects of benzo[a]pyrene and hydroquinone. PMID:25228686

  1. The direct collapse of a massive black hole seed under the influence of an anisotropic Lyman-Werner source

    SciTech Connect

    Regan, John A.; Johansson, Peter H.; Wise, John H.

    2014-11-10

    The direct collapse model of supermassive black hole seed formation requires that the gas cools predominantly via atomic hydrogen. To this end we simulate the effect of an anisotropic radiation source on the collapse of a halo at high redshift. The radiation source is placed at a distance of 3 kpc (physical) from the collapsing object and is set to emit monochromatically in the center of the Lyman-Werner (LW) band. The LW radiation emitted from the high redshift source is followed self-consistently using ray tracing techniques. Due to self-shielding, a small amount of H{sub 2} is able to form at the very center of the collapsing halo even under very strong LW radiation. Furthermore, we find that a radiation source, emitting >10{sup 54} (∼ 10{sup 3} J{sub 21}) photons s{sup –1}, is required to cause the collapse of a clump of M ∼ 10{sup 5} M {sub ☉}. The resulting accretion rate onto the collapsing object is ∼0.25 M {sub ☉} yr{sup –1}. Our results display significant differences, compared to the isotropic radiation field case, in terms of the H{sub 2} fraction at an equivalent radius. These differences will significantly affect the dynamics of the collapse. With the inclusion of a strong anisotropic radiation source, the final mass of the collapsing object is found to be M ∼ 10{sup 5} M {sub ☉}. This is consistent with predictions for the formation of a supermassive star or quasi-star leading to a supermassive black hole.

  2. Stable microsatellite length but frequent allele loss in SV40-immortalized Werner syndrome and control cell lines

    SciTech Connect

    Brokks-Wilson, A.R.; Monnat, R.J. Jr.

    1994-09-01

    We have determined the mitotic stability of microsatellite alleles and allele lengths in SV40-immortalized Werner syndrome (WS) and control cell lines. The impetus for this work was presence of a mutator phenotype in WS cells and cell lines and the association between a DNA mismatch repair deficit and microsatellite length instability in a heritable human tumor syndrome. Thus the identification of microsatellite length instability in WS cells might provide a clue to the primary biochemical defect in WS and a partial explanation for the mutator phenotype and the elevated cancer risk of WS patients. Five microsatellite loci (D2S123, D10S197, D10S141, D8S255, and D8S87) were PCR genotyped in 88 independent clones derived from four SV40-immortalized fibroblast cell lines (two WS lines: WV1 and PSV811; and two control lines: GM637 and GM639). Stable allele lengths were transmitted from cell line to clones in every case. WS cell line WV1 contained a preexisting faint third D2S123 allele which was transmitted with the other two D2S123 alleles to a majority of WV1 clones. In contrast, microsatellite allele loss was common: complete absence of one of two alleles was seen in 30% of control and in 3% of WS clones. Complete allele loss likely results from a clonal population being derived from a cell lacking a microsatellite allele. Altered relative band intensities in clones compared to parental lines were very common in both WS and control backgrounds (40% of all clones). This suggests that allele loss is common and continues upon post-cloning cell culture. These allele losses are likely to be a consequence of the genetic instability that accompanies SV40 immortalization. These results indicate that SV40-immortalized cell lines are genetically heterogeneous, and that the genotypes of individual clones may incompletely represent the genomes of the primary cells from which they were derived.

  3. Metabolic and Phenotypic Differences between Mice Producing a Werner Syndrome Helicase Mutant Protein and Wrn Null Mice.

    PubMed

    Aumailley, Lucie; Garand, Chantal; Dubois, Marie Julie; Johnson, F Brad; Marette, André; Lebel, Michel

    2015-01-01

    Werner syndrome (WS) is a premature aging disorder caused by mutations in a RecQ-family DNA helicase, WRN. Mice lacking part of the helicase domain of the WRN orthologue exhibit many phenotypic features of WS, including metabolic abnormalities and a shorter mean life span. In contrast, mice lacking the entire Wrn protein (i.e. Wrn null mice) do not exhibit a premature aging phenotype. In this study, we used a targeted mass spectrometry-based metabolomic approach to identify serum metabolites that are differentially altered in young Wrn helicase mutant and Wrn null mice. An antibody-based quantification of 43 serum cytokines and markers of cardiovascular disease risk complemented this study. We found that Wrn helicase mutants exhibited elevated and decreased levels, respectively, of the anti-inflammatory cytokine IL-10 and the pro-inflammatory cytokine IL-18. Wrn helicase mutants also exhibited an increase in serum hydroxyproline and plasminogen activator inhibitor-1, markers of extracellular matrix remodeling of the vascular system and inflammation in aging. We also observed an abnormal increase in the ratio of very long chain to short chain lysophosphatidylcholines in the Wrn helicase mutants underlying a peroxisome perturbation in these mice. Remarkably, the Wrn mutant helicase protein was mislocalized to the endoplasmic reticulum and the peroxisomal fractions in liver tissues. Additional analyses with mouse embryonic fibroblasts indicated a severe defect of the autophagy flux in cells derived from Wrn helicase mutants compared to wild type and Wrn null animals. These results indicate that the deleterious effects of the helicase-deficient Wrn protein are mediated by the dysfunction of several cellular organelles. PMID:26447695

  4. Metabolic and Phenotypic Differences between Mice Producing a Werner Syndrome Helicase Mutant Protein and Wrn Null Mice

    PubMed Central

    Aumailley, Lucie; Garand, Chantal; Dubois, Marie Julie; Johnson, F. Brad; Marette, André; Lebel, Michel

    2015-01-01

    Werner syndrome (WS) is a premature aging disorder caused by mutations in a RecQ-family DNA helicase, WRN. Mice lacking part of the helicase domain of the WRN orthologue exhibit many phenotypic features of WS, including metabolic abnormalities and a shorter mean life span. In contrast, mice lacking the entire Wrn protein (i.e. Wrn null mice) do not exhibit a premature aging phenotype. In this study, we used a targeted mass spectrometry-based metabolomic approach to identify serum metabolites that are differentially altered in young Wrn helicase mutant and Wrn null mice. An antibody-based quantification of 43 serum cytokines and markers of cardiovascular disease risk complemented this study. We found that Wrn helicase mutants exhibited elevated and decreased levels, respectively, of the anti-inflammatory cytokine IL-10 and the pro-inflammatory cytokine IL-18. Wrn helicase mutants also exhibited an increase in serum hydroxyproline and plasminogen activator inhibitor-1, markers of extracellular matrix remodeling of the vascular system and inflammation in aging. We also observed an abnormal increase in the ratio of very long chain to short chain lysophosphatidylcholines in the Wrn helicase mutants underlying a peroxisome perturbation in these mice. Remarkably, the Wrn mutant helicase protein was mislocalized to the endoplasmic reticulum and the peroxisomal fractions in liver tissues. Additional analyses with mouse embryonic fibroblasts indicated a severe defect of the autophagy flux in cells derived from Wrn helicase mutants compared to wild type and Wrn null animals. These results indicate that the deleterious effects of the helicase-deficient Wrn protein are mediated by the dysfunction of several cellular organelles. PMID:26447695

  5. The DNA repair endonuclease XPG interacts directly and functionally with the WRN helicase defective in Werner syndrome

    SciTech Connect

    Trego, Kelly S.; Chernikova, Sophia B.; Davalos, Albert R.; Perry, J. Jefferson P.; Finger, L. David; Ng, Cliff; Tsai, Miaw-Sheue; Yannone, Steven M.; Tainer, John A.; Campisi, Judith; Cooper, Priscilla K.

    2011-04-20

    XPG is a structure-specific endonuclease required for nucleotide excision repair (NER). XPG incision defects result in the cancer-prone syndrome xeroderma pigmentosum, whereas truncating mutations of XPG cause the severe postnatal progeroid developmental disorder Cockayne syndrome. We show that XPG interacts directly with WRN protein, which is defective in the premature aging disorder Werner syndrome, and that the two proteins undergo similar sub-nuclear redistribution in S-phase and co-localize in nuclear foci. The co-localization was observed in mid- to late-S-phase, when WRN moves from nucleoli to nuclear foci that have been shown to contain protein markers of both stalled replication forks and telomeric proteins. We mapped the interaction between XPG and WRN to the C-terminal domains of each and show that interaction with the C-terminal domain of XPG strongly stimulates WRN helicase activity. WRN also possesses a competing DNA single-strand annealing activity that, combined with unwinding, has been shown to coordinate regression of model replication forks to form Holliday junction/chicken foot intermediate structures. We tested whether XPG stimulated WRN annealing activity and found that XPG itself has intrinsic strand annealing activity that requires the unstructured R- and C-terminal domains, but not the conserved catalytic core or endonuclease activity. Annealing by XPG is cooperative, rather than additive, with WRN annealing. Taken together, our results suggest a novel function for XPG in S-phase that is at least in part carried out coordinately with WRN, and which may contribute to the severity of the phenotypes that occur upon loss of XPG.

  6. Homologous recombination is elevated in some Werner-like syndromes but not during normal in vitro or in vivo senescence of mammalian cells.

    PubMed

    Cheng, R Z; Murano, S; Kurz, B; Shmookler Reis, R J

    1990-01-01

    Werner syndrome (WS) is a recessive genetic condition associated with markedly reduced replicative lifespans of cells in culture, high chromosomal instability in vivo and in vitro, and premature appearance of many characteristics of normal aging, including an increased incidence of cancer. We have monitored plasmid homologous recombination frequencies in diploid fibroblasts from 6 Werner or Werner-like syndrome patients, following transfection with a plasmid substrate containing 2 overlapping fragments of the TN5 Neor gene. Plasmid DNA recovered from these cells was then assayed for homologous recombination by (a) transformation of recA- bacteria to Ampr (indicating total viable plasmid) or Neor (indicating viable recombinant plasmid), and (b) by limited-cycle polymerase chain reaction (PCR) to co-amplify a recombinant fragment containing the overlap region, and a control region of the same plasmid, without bacterial transformation. Bacterial assay data indicated that recombination rates in 3 of the 6 WS strains were significantly elevated above normal controls; 4 of 6 appeared elevated by PCR assay. The highest-recombination WS strain showed evidence of reduced degradation of transfected plasmid DNA. For this small sample of WS strains, clinical severity of WS was not well correlated with recombination rate as determined by either assay (Pearson r = 0.78, not significant, for PCR assay); elevated recombination may, however, define a subset of WS at greatest risk for cancer and/or atherosclerosis. PCR assay of a hyperoxia-resistant HeLa cell line, displaying substantially increased chromosome breakage, indicated increased recombination between direct-repeat fragments. Nevertheless, elevated recombination in WS strains is unlikely to be secondary to impaired replicative capacity characteristic of WS cells, or to defective repair of chromosome damage which is increased in WS, since recombination in non-WS strains was unaffected by passage level or repeated UV

  7. Bernard Lerer: recipient of the 2014 inaugural Werner Kalow Responsible Innovation Prize in Global Omics and Personalized Medicine (Pacific Rim Association for Clinical Pharmacogenetics).

    PubMed

    Ozdemir, Vural; Endrenyi, Laszlo; Aynacıoğlu, Sükrü; Bragazzi, Nicola Luigi; Dandara, Collet; Dove, Edward S; Ferguson, Lynnette R; Geraci, Christy Jo; Hafen, Ernst; Kesim, Belgin Eroğlu; Kolker, Eugene; Lee, Edmund J D; Llerena, Adrian; Nacak, Muradiye; Shimoda, Kazutaka; Someya, Toshiyuki; Srivastava, Sanjeeva; Tomlinson, Brian; Vayena, Effy; Warnich, Louise; Yaşar, Umit

    2014-04-01

    This article announces the recipient of the 2014 inaugural Werner Kalow Responsible Innovation Prize in Global Omics and Personalized Medicine by the Pacific Rim Association for Clinical Pharmacogenetics (PRACP): Bernard Lerer, professor of psychiatry and director of the Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel. The Werner Kalow Responsible Innovation Prize is given to an exceptional interdisciplinary scholar who has made highly innovative and enduring contributions to global omics science and personalized medicine, with both vertical and horizontal (transdisciplinary) impacts. The prize is established in memory of a beloved colleague, mentor, and friend, the late Professor Werner Kalow, who cultivated the idea and practice of pharmacogenetics in modern therapeutics commencing in the 1950s. PRACP, the prize's sponsor, is one of the longest standing learned societies in the Asia-Pacific region, and was founded by Kalow and colleagues more than two decades ago in the then-emerging field of pharmacogenetics. In announcing this inaugural prize and its winner, we seek to highlight the works of prize winner, Professor Lerer. Additionally, we contextualize the significance of the prize by recalling the life and works of Professor Kalow and providing a brief socio-technical history of the rise of pharmacogenetics and personalized medicine as a veritable form of 21(st) century scientific practice. The article also fills a void in previous social science analyses of pharmacogenetics, by bringing to the fore the works of Kalow from 1995 to 2008, when he presciently noted the rise of yet another field of postgenomics inquiry--pharmacoepigenetics--that railed against genetic determinism and underscored the temporal and spatial plasticity of genetic components of drug response, with invention of the repeated drug administration (RDA) method that estimates the dynamic heritabilities of drug response. The prize goes a long way

  8. Herlyn-Werner-Wunderlich Syndrome: A Rare Cause of Pelvic Pain and High CA 19-9 Levels in an Adolescent Girl

    PubMed Central

    Unal, Emel; Sonmezer, Murat; Erkol, Hatice Gul; Fitoz, Suat

    2016-01-01

    Herlyn-Werner-Wunderlich (HWW) syndrome is a rare developmental anomaly that includes uterus didelphys with obstructed hemivagina and ipsilateral renal agenesis. A 13-year-old girl presented with chronic abdominal pain. Magnetic resonance imaging revealed uterus didelphys, hematometrocolpos and renal agenesis on the right side with imperforate hymen. Subsequently the patient was found to have Mullerian duct anomalies. CA 19-9 level was high. At laparoscopy combined with vaginoscopy hematocolpos was drained following which she improved clinically and CA 19-9 level returned to normal. PMID:26816677

  9. Herlyn-Werner-Wunderlich Syndrome: A Rare Cause of Pelvic Pain and High CA 19-9 Levels in an Adolescent Girl.

    PubMed

    Unal, Emel; Tanyildiz, Hikmet Gulsah; Sonmezer, Murat; Erkol, Hatice Gul; Fitoz, Suat

    2016-01-01

    Herlyn-Werner-Wunderlich (HWW) syndrome is a rare developmental anomaly that includes uterus didelphys with obstructed hemivagina and ipsilateral renal agenesis. A 13-year-old girl presented with chronic abdominal pain. Magnetic resonance imaging revealed uterus didelphys, hematometrocolpos and renal agenesis on the right side with imperforate hymen. Subsequently the patient was found to have Mullerian duct anomalies. CA 19-9 level was high. At laparoscopy combined with vaginoscopy hematocolpos was drained following which she improved clinically and CA 19-9 level returned to normal.

  10. Law of cooling, heat conduction and Stefan-Boltzmann radiation laws fitted to experimental data for bones irradiated by CO2 laser

    PubMed Central

    Lévesque, Luc

    2014-01-01

    The rate of cooling of domesticated pig bones is investigated within the temperature range of 20°C-320°C. Within the afore-mentioned temperature range, it was found that different behaviors in the rate of cooling were taking place. For bones reaching a temperature within the lower temperature range of 20°C-50°C, it was found that the rate of cooling is mostly governed by the empirical Newton’s law of cooling. It is also shown that a transition is taking place somewhere within 50°C-100°C, where both the heat conduction equation and Newton’s law apply. As bones can be raised at a fairly high temperature before burning, it was found that the rate of cooling within the range 125°C-320°C is mostly behaving according to the heat conduction equation and Stefan-Boltzmann radiation law. A pulsed CO2 laser was used to heat the bones up to a given temperature and the change of temperature as a function of time was recorded by non-contact infrared thermometer during the cooling period. PMID:24688807

  11. Law of cooling, heat conduction and Stefan-Boltzmann radiation laws fitted to experimental data for bones irradiated by CO2 laser.

    PubMed

    Lévesque, Luc

    2014-03-01

    The rate of cooling of domesticated pig bones is investigated within the temperature range of 20°C-320°C. Within the afore-mentioned temperature range, it was found that different behaviors in the rate of cooling were taking place. For bones reaching a temperature within the lower temperature range of 20°C-50°C, it was found that the rate of cooling is mostly governed by the empirical Newton's law of cooling. It is also shown that a transition is taking place somewhere within 50°C-100°C, where both the heat conduction equation and Newton's law apply. As bones can be raised at a fairly high temperature before burning, it was found that the rate of cooling within the range 125°C-320°C is mostly behaving according to the heat conduction equation and Stefan-Boltzmann radiation law. A pulsed CO2 laser was used to heat the bones up to a given temperature and the change of temperature as a function of time was recorded by non-contact infrared thermometer during the cooling period.

  12. Sign Crossover in All Maxwell-Stefan Diffusivities for Molten Salt LiF-BeF2: A Molecular Dynamics Study.

    PubMed

    Chakraborty, Brahmananda

    2015-08-20

    Applying Green-Kubo formalism and equilibrium molecular dynamics (MD) simulations, we have studied for the first time the dynamic correlation, Onsager coefficients, and Maxwell-Stefan (MS) diffusivities of molten salt LiF-BeF2, which is a potential candidate for a coolant in a high temperature reactor. We observe an unusual composition dependence and strikingly a crossover in sign for all the MS diffusivities at a composition of around 7% of LiF where the MS diffusivity between cation-anion pair (Đ(BeF) and Đ(LiF)) jumps from positive to negative value while the MS diffusivity between cation-cation pair (Đ(LiBe)) becomes positive from a negative value. Even though the negative MS diffusivities have been observed for electrolyte solutions between cation-cation pair, here we report negative MS diffusivity between cation-anion pair where Đ(BeF) shows a sharp rise around 66% of BeF2, reaches maximum value at 70% of BeF2, and then decreases almost exponentially with a sign change for BeF2 around 93%. For low mole fraction of LiF, Đ(BeF) follows the Debye-Huckel theory and rises with the square root of LiF mole fraction similar to the MS diffusivity between cation-anion pair in aqueous solution of electrolyte salt. Negative MS diffusivities while unusual are, however, shown to satisfy the non-negative entropy constraints at all thermodynamic states as required by the second law of thermodynamics. We have established a strong correlation between the structure and dynamics and predict that the formation of flouride polyanion network between Be and F ions and coulomb interaction is responsible for sharp variation of the MS diffusivities which controls the multicomponent diffusion phenomenon in LiF-BeF2 which has a strong impact on the performance of the reactor.

  13. Bernard Lerer: Recipient of the 2014 Inaugural Werner Kalow Responsible Innovation Prize in Global Omics and Personalized Medicine (Pacific Rim Association for Clinical Pharmacogenetics)

    PubMed Central

    Aynacıoğlu, Şükrü; Bragazzi, Nicola Luigi; Dandara, Collet; Dove, Edward S.; Ferguson, Lynnette R.; Geraci, Christy Jo; Hafen, Ernst; Kesim, Belgin Eroğlu; Kolker, Eugene; Lee, Edmund J.D.; LLerena, Adrian; Nacak, Muradiye; Shimoda, Kazutaka; Someya, Toshiyuki; Srivastava, Sanjeeva; Tomlinson, Brian; Vayena, Effy; Warnich, Louise; Yaşar, Ümit

    2014-01-01

    Abstract This article announces the recipient of the 2014 inaugural Werner Kalow Responsible Innovation Prize in Global Omics and Personalized Medicine by the Pacific Rim Association for Clinical Pharmacogenetics (PRACP): Bernard Lerer, professor of psychiatry and director of the Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel. The Werner Kalow Responsible Innovation Prize is given to an exceptional interdisciplinary scholar who has made highly innovative and enduring contributions to global omics science and personalized medicine, with both vertical and horizontal (transdisciplinary) impacts. The prize is established in memory of a beloved colleague, mentor, and friend, the late Professor Werner Kalow, who cultivated the idea and practice of pharmacogenetics in modern therapeutics commencing in the 1950s. PRACP, the prize's sponsor, is one of the longest standing learned societies in the Asia-Pacific region, and was founded by Kalow and colleagues more than two decades ago in the then-emerging field of pharmacogenetics. In announcing this inaugural prize and its winner, we seek to highlight the works of prize winner, Professor Lerer. Additionally, we contextualize the significance of the prize by recalling the life and works of Professor Kalow and providing a brief socio-technical history of the rise of pharmacogenetics and personalized medicine as a veritable form of 21st century scientific practice. The article also fills a void in previous social science analyses of pharmacogenetics, by bringing to the fore the works of Kalow from 1995 to 2008, when he presciently noted the rise of yet another field of postgenomics inquiry—pharmacoepigenetics—that railed against genetic determinism and underscored the temporal and spatial plasticity of genetic components of drug response, with invention of the repeated drug administration (RDA) method that estimates the dynamic heritabilities of drug response. The prize goes a

  14. Trapping of Li(+) Ions by [ThFn](4-n) Clusters Leading to Oscillating Maxwell-Stefan Diffusivity in the Molten Salt LiF-ThF4.

    PubMed

    Chakraborty, Brahmananda; Kidwai, Sharif; Ramaniah, Lavanya M

    2016-08-18

    A molten salt mixture of lithium fluoride and thorium fluoride (LiF-ThF4) serves as a fuel as well as a coolant in the most sophisticated molten salt reactor (MSR). Here, we report for the first time dynamic correlations, Onsager coefficients, Maxwell-Stefan (MS) diffusivities, and the concentration dependence of density and enthalpy of the molten salt mixture LiF-ThF4 at 1200 K in the composition range of 2-45% ThF4 and also at eutectic composition in the temperature range of 1123-1600 K using Green-Kubo formalism and equilibrium molecular dynamics simulations. We have observed an interesting oscillating pattern for the MS diffusivity for the cation-cation pair, in which ĐLi-Th oscillates between positive and negative values with the amplitude of the oscillation reducing as the system becomes rich in ThF4. Through the velocity autocorrelation function, vibrational density of states, radial distribution function analysis, and structural snapshots, we establish an interplay between the local structure and multicomponent dynamics and predict that formation of negatively charged [ThFn](4-n) clusters at a higher ThF4 mole % makes positively charged Li(+) ions oscillate between different clusters, with their range of motion reducing as the number of [ThFn](4-n) clusters increases, and finally Li(+) ions almost get trapped at a higher ThF4% when the electrostatic force on Li(+) exerted by various surrounding clusters gets balanced. Although reports on variations of density and enthalpy with temperature exist in the literature, for the first time we report variations of the density and enthalpy of LiF-ThF4 with the concentration of ThF4 (mole %) and fit them with the square root function of ThF4 concentration, which will be very useful for experimentalists to obtain data over a range of concentrations from fitting the formula for design purposes. The formation of [ThFn](4-n) clusters and the reduction in the diffusivity of the ions at a higher ThF4% may limit the

  15. Trapping of Li(+) Ions by [ThFn](4-n) Clusters Leading to Oscillating Maxwell-Stefan Diffusivity in the Molten Salt LiF-ThF4.

    PubMed

    Chakraborty, Brahmananda; Kidwai, Sharif; Ramaniah, Lavanya M

    2016-08-18

    A molten salt mixture of lithium fluoride and thorium fluoride (LiF-ThF4) serves as a fuel as well as a coolant in the most sophisticated molten salt reactor (MSR). Here, we report for the first time dynamic correlations, Onsager coefficients, Maxwell-Stefan (MS) diffusivities, and the concentration dependence of density and enthalpy of the molten salt mixture LiF-ThF4 at 1200 K in the composition range of 2-45% ThF4 and also at eutectic composition in the temperature range of 1123-1600 K using Green-Kubo formalism and equilibrium molecular dynamics simulations. We have observed an interesting oscillating pattern for the MS diffusivity for the cation-cation pair, in which ĐLi-Th oscillates between positive and negative values with the amplitude of the oscillation reducing as the system becomes rich in ThF4. Through the velocity autocorrelation function, vibrational density of states, radial distribution function analysis, and structural snapshots, we establish an interplay between the local structure and multicomponent dynamics and predict that formation of negatively charged [ThFn](4-n) clusters at a higher ThF4 mole % makes positively charged Li(+) ions oscillate between different clusters, with their range of motion reducing as the number of [ThFn](4-n) clusters increases, and finally Li(+) ions almost get trapped at a higher ThF4% when the electrostatic force on Li(+) exerted by various surrounding clusters gets balanced. Although reports on variations of density and enthalpy with temperature exist in the literature, for the first time we report variations of the density and enthalpy of LiF-ThF4 with the concentration of ThF4 (mole %) and fit them with the square root function of ThF4 concentration, which will be very useful for experimentalists to obtain data over a range of concentrations from fitting the formula for design purposes. The formation of [ThFn](4-n) clusters and the reduction in the diffusivity of the ions at a higher ThF4% may limit the

  16. A novel ZRS mutation leads to preaxial polydactyly type 2 in a heterozygous form and Werner mesomelic syndrome in a homozygous form.

    PubMed

    VanderMeer, Julia E; Lozano, Reymundo; Sun, Miao; Xue, Yuan; Daentl, Donna; Jabs, Ethylin Wang; Wilcox, William R; Ahituv, Nadav

    2014-08-01

    Point mutations in the zone of polarizing activity regulatory sequence (ZRS) are known to cause human limb malformations. Although most mutations cause preaxial polydactyly (PPD), triphalangeal thumb (TPT) or both, a mutation in position 404 of the ZRS causes more severe Werner mesomelic syndrome (WMS) for which malformations include the distal arm or leg bones in addition to the hands and/or feet. Of more than 15 reported families with ZRS mutations, only one homozygous individual has been reported, with no change in phenotype compared with heterozygotes. Here, we describe a novel point mutation in the ZRS, 402C>T (AC007097.4:g.105548C>T), that is transmitted through two Mexican families with one homozygous individual. The homozygous phenotype for this mutation, WMS, is more severe than the numerous heterozygous individuals genotyped from both families who have TPT and PPD. A mouse transgenic enhancer assay shows that this mutation causes an expansion of the enhancer's expression domain in the developing mouse limb, confirming its pathogenicity. Combined, our results identify a novel ZRS mutation in the Mexican population, 402C>T, and suggest that a dosage effect exists for this ZRS mutation.

  17. Improved Laboratory Values of the H{sub 2} Lyman and Werner Lines for Constraining Time Variation of the Proton-to-Electron Mass Ratio

    SciTech Connect

    Salumbides, E. J.; Khramov, A.; Wolf, A. L.; Eikema, K. S. E.; Ubachs, W.; Bailly, D.; Vervloet, M.

    2008-11-28

    Two distinct high-accuracy laboratory spectroscopic investigations of the H{sub 2} molecule are reported. Anchor lines in the EF{sup 1}{sigma}{sub g}{sup +}-X{sup 1}{sigma}{sub g}{sup +} system are calibrated by two-photon deep-UV Doppler-free spectroscopy, while independent Fourier-transform spectroscopic measurements are performed that yield accurate spacings in the B{sup 1}{sigma}{sub u}{sup +}-EF{sup 1}{sigma}{sub g}{sup +} and I{sup 1}{pi}{sub g}-C{sup 1}{pi}{sub u} systems. From combination differences accurate transition wavelengths for the B-X Lyman and the C-X Werner lines can be determined with accuracies better than {approx}5x10{sup -9}, representing a major improvement over existing values. This metrology provides a practically exact database to extract a possible variation of the proton-to-electron mass ratio based on H{sub 2} lines in high-redshift objects. Moreover, it forms a rationale for equipping a future class of telescopes, carrying 30-40 m dishes, with novel spectrometers of higher resolving powers.

  18. Increased susceptibility to oxidative stress- and ultraviolet A-induced apoptosis in fibroblasts in atypical progeroid syndrome/atypical Werner syndrome with LMNA mutation.

    PubMed

    Motegi, Sei-Ichiro; Uchiyama, Akihiko; Yamada, Kazuya; Ogino, Sachiko; Yokoyama, Yoko; Perera, Buddhini; Takeuchi, Yuko; Ishikawa, Osamu

    2016-08-01

    Atypical progeroid syndrome (APS), including atypical Werner syndrome (AWS), is a disorder of premature ageing caused by mutation of the lamin A gene, the same causal gene involved in Hutchinson-Gilford syndrome (HGS). We previously reported the first Japanese case of APS/AWS with a LMNA mutation (p.D300N). Recently, it has been reported that UVA induced abnormal truncated form of lamin A, called progerin, as well as HGS-like abnormal nuclear structures in normal human fibroblasts, being more frequent in the elderly, suggesting that lamin A may be involved in the regulation of photoageing. The objective of this study was to elucidate the sensitivity to cell damage induced by oxidative stress or UVA in fibroblasts from APS/AWS patient. Using immunofluorescence staining and flow cytometry analysis, the amount of early apoptotic cells and degree of intra-cellular reactive oxygen species (ROS) generation were higher in H2 02 - or UVA-treated APS/AWS fibroblasts than in normal fibroblasts, suggesting that repeated UV exposure may induce premature ageing of the skin in APS/AWS patients and that protecting against sunlight is possibly important for delaying the emergence of APS/AWS symptoms. In addition, we demonstrated that H2 O2 -, or UVA-induced apoptosis and necrosis in normal and APS/AWS fibroblasts were enhanced by farnesyltransferase inhibitor (FTI) treatment, indicating that FTI might not be useful for treating our APS/AWS patient. PMID:27539898

  19. Vascular access: an historical perspective from Sir William Harvey to the 1956 Nobel prize to André F. Cournand, Werner Forssmann, and Dickinson W. Richards.

    PubMed

    Sette, Piersandro; Dorizzi, Romolo M; Azzini, Anna M

    2012-01-01

    Sir William Harvey (1578-1657), who had many precursors, discovered blood circulation in 1628 after a significant number of anatomic dissection of cadavers; his studies were continued by Sir Christopher Wren and Daniel Johann Major. The first central vein catheterization was performed on a horse by Stephen Hales, an English Vicar. In 1844, a century later, the French biologist Claude Bernard attempted the first carotid artery cannulation and repeated the procedure in the jugular vein, again on a horse. He was first to report the complications now well known to be associated with this maneuver. In 1929 Werner Forssmann tried cardiac catheterization on himself, but could not investigate the procedure further since his findings were rejected and ridiculed by colleagues. His work was continued by André Frédéric Cournand and Dickinson Woodruff Richards Jr in the United States. In 1956 the three physicians shared the Nobel Prize for Medicine for their studies on vascular and cardiac systems. The genius and the perseverance of the three physicians paved the way towards peripheral and central catheter vein placement, one of the most frequently performed maneuvers in hospitals. Its history still remains unknown to most and deserves a short description. PMID:21983826

  20. Serines 440 and 467 in the Werner syndrome protein are phosphorylated by DNA-PK and affects its dynamics in response to DNA double strand breaks.

    PubMed

    Kusumoto-Matsuo, Rika; Ghosh, Deblina; Karmakar, Parimal; May, Alfred; Ramsden, Dale; Bohr, Vilhelm A

    2014-01-01

    WRN protein, defective in Werner syndrome (WS), a human segmental progeria, is a target of serine/threonine kinases involved in sensing DNA damage. DNA-PK phosphorylates WRN in response to DNA double strand breaks (DSBs). However, the main phosphorylation sites and functional importance of the phosphorylation of WRN has remained unclear. Here, we identify Ser-440 and -467 in WRN as major phosphorylation sites mediated by DNA-PK.In vitro, DNA-PK fails to phosphorylate a GST-WRN fragment with S440A and/or S467A substitution. In addition, full length WRN with the mutation expressed in 293T cells was not phosphorylated in response to DSBs produced by bleomycin. Accumulation of the mutant WRN at the site of laser-induced DSBs occurred with the same kinetics as wild type WRN in live HeLa cells. While the wild type WRN relocalized to the nucleoli after 24 hours recovery from etoposide-induced DSBs, the mutant WRN remained mostly in the nucleoplasm. Consistent with this, WS cells expressing the mutants exhibited less DNA repair efficiency and more sensitivity to etoposide, compared to those expressing wild type. Our findings indicate that phosphorylation of Ser-440 and -467 in WRN are important for relocalization of WRN to nucleoli, and that it is required for efficient DSB repair.

  1. Niels Bohr's discussions with Albert Einstein, Werner Heisenberg, and Erwin Schrödinger: The origins of the principles of uncertainty and complementarity

    NASA Astrophysics Data System (ADS)

    Mehra, Jagdish

    1987-05-01

    In this paper, the main outlines of the discussions between Niels Bohr with Albert Einstein, Werner Heisenberg, and Erwin Schrödinger during 1920 1927 are treated. From the formulation of quantum mechanics in 1925 1926 and wave mechanics in 1926, there emerged Born's statistical interpretation of the wave function in summer 1926, and on the basis of the quantum mechanical transformation theory—formulated in fall 1926 by Dirac, London, and Jordan—Heisenberg formulated the uncertainty principle in early 1927. At the Volta Conference in Como in September 1927 and at the fifth Solvay Conference in Brussels the following month, Bohr publicly enunciated his complementarity principle, which had been developing in his mind for several years. The Bohr-Einstein discussions about the consistency and completeness of qnautum mechanics and of physical theory as such—formally begun in October 1927 at the fifth Solvay Conference and carried on at the sixth Solvay Conference in October 1930—were continued during the next decades. All these aspects are briefly summarized.

  2. Toward localization of the Werner syndrome gene by linkage disequilibrium and ancestral haplotyping: Lessons learned from analysis of 35 chromosome 8p11.1-21.1 markers

    SciTech Connect

    Goddard, K.A.B.; Wijsman, E.M.; Martin, G.M.

    1996-06-01

    Werner syndrome (WS) is an autosomal recessive disorder characterized by premature onset of a number of age-related diseases. The gene for WS, WRN, has been mapped to the 8p11.1-21.1 region with further localization through linkage disequilibrium mapping. Here we present the results of linkage disequilibrium and ancestral haplotype analyses of 35 markers to further refine the location of WRN. We identified an interval in this region in which 14 of 18 markers tested show significant evidence of linkage disequilibrium in at least one of the two populations tested. Analysis of extended and partial haplotypes covering 21 of the markers studied supports the existence of both obligate and probable ancestral recombinant events which localize WRN almost certainly to the interval between DSS2196 and D8S2186, and most likely to the narrower interval between D8S2168 and D8S2186. These haplotype analyses also suggest that there are multiple WRN mutations in each of the two populations under study. We also present a comparison of approaches to performing disequilibrium tests with multiallelic markers, and show that some commonly used approximations for such tests perform poorly in comparison to exact probability tests. Finally, we discuss some of the difficulties introduced by the high mutation rate at microsatellite markers which influence our ability to use ancestral haplotype analysis to localize disease genes. 51 refs., 6 figs., 7 tabs.

  3. A missense single nucleotide polymorphism, V114I of the Werner syndrome gene, is associated with risk of osteoporosis and femoral fracture in the Japanese population.

    PubMed

    Zhou, Heying; Mori, Seijiro; Tanaka, Masashi; Sawabe, Motoji; Arai, Tomio; Muramatsu, Masaaki; Mieno, Makiko Naka; Shinkai, Shoji; Yamada, Yoshiji; Miyachi, Motohiko; Murakami, Haruka; Sanada, Kiyoshi; Ito, Hideki

    2015-11-01

    Werner syndrome is a rare autosomal recessive disorder caused by mutations in the human WRN gene and characterized by the early onset of normal aging symptoms. Given that patients with this disease exhibit osteoporosis, the present study aimed to determine whether the WRN gene contributes to the etiology of osteoporosis. A genetic association study of eight non-synonymous polymorphisms in the WRN gene and the incidence of femoral fracture was undertaken in 1,632 consecutive Japanese autopsies in which 140 patients had experienced the fracture during their lifetime. The results were validated in 251 unrelated postmenopausal Japanese women with osteoporosis and 269 non-institutionalized, community-dwelling Japanese adults. A statistically significant association was observed between rs2230009 (c.340G > A)--which results in a Val to Ile substitution--and fracture risk; the incidence of femoral fracture increased dose-dependently with the number of A alleles (p = 0.0120). Femoral neck bone and whole bone densities were lower among postmenopausal women with osteoporosis and community-dwelling adults, respectively, if they were of the AG instead of the GG genotype. The results suggest that Japanese subjects bearing at least one A allele of rs2230009 of the WRN gene are at a significantly higher risk of femoral fracture, possibly due to decreased bone density.

  4. Vascular access: an historical perspective from Sir William Harvey to the 1956 Nobel prize to André F. Cournand, Werner Forssmann, and Dickinson W. Richards.

    PubMed

    Sette, Piersandro; Dorizzi, Romolo M; Azzini, Anna M

    2012-01-01

    Sir William Harvey (1578-1657), who had many precursors, discovered blood circulation in 1628 after a significant number of anatomic dissection of cadavers; his studies were continued by Sir Christopher Wren and Daniel Johann Major. The first central vein catheterization was performed on a horse by Stephen Hales, an English Vicar. In 1844, a century later, the French biologist Claude Bernard attempted the first carotid artery cannulation and repeated the procedure in the jugular vein, again on a horse. He was first to report the complications now well known to be associated with this maneuver. In 1929 Werner Forssmann tried cardiac catheterization on himself, but could not investigate the procedure further since his findings were rejected and ridiculed by colleagues. His work was continued by André Frédéric Cournand and Dickinson Woodruff Richards Jr in the United States. In 1956 the three physicians shared the Nobel Prize for Medicine for their studies on vascular and cardiac systems. The genius and the perseverance of the three physicians paved the way towards peripheral and central catheter vein placement, one of the most frequently performed maneuvers in hospitals. Its history still remains unknown to most and deserves a short description.

  5. Cobalt(III) Werner Complexes with 1,2-Diphenylethylenediamine Ligands: Readily Available, Inexpensive, and Modular Chiral Hydrogen Bond Donor Catalysts for Enantioselective Organic Synthesis.

    PubMed

    Lewis, Kyle G; Ghosh, Subrata K; Bhuvanesh, Nattamai; Gladysz, John A

    2015-03-25

    In the quest for new catalysts that can deliver single enantiomer pharmaceuticals and agricultural chemicals, chemists have extensively mined the "chiral pool", with little in the way of inexpensive, readily available building blocks now remaining. It is found that Werner complexes based upon the D3 symmetric chiral trication [Co(en)3](3+) (en = 1,2-ethylenediamine), which features an earth abundant metal and cheap ligand type, and was among the first inorganic compounds resolved into enantiomers 103 years ago, catalyze a valuable carbon-carbon bond forming reaction, the Michael addition of malonate esters to nitroalkenes, in high enantioselectivities and without requiring inert atmosphere conditions. The title catalysts, [Co((S,S)-dpen)3](3+) ((S,S)-3 (3+)) 3X(-), employ a commercially available chiral ligand, (S,S)-1,2-diphenylethylenediamine. The rates and ee values are functions of the configuration of the cobalt center (Λ/Δ) and the counteranions, which must be lipophilic to solubilize the trication in nonaqueous media. The highest enantioselectivities are obtained with Λ and 2Cl(-)BArf (-), 2BF4 (-)BArf (-), or 3BF4 (-) salts (BArf (-) = B(3,5-C6H3(CF3)2)4 (-)). The substrates are not activated by metal coordination, but rather by second coordination sphere hydrogen bonding involving the ligating NH2 groups. Crystal structures and NMR data indicate enthalpically stronger interactions with the NH moieties related by the C3 symmetry axis, as opposed to those related by the C2 symmetry axes; rate trends and other observations suggest this to be the catalytically active site. Both Λ- and Δ-(S,S)-3 (3+) 2Cl(-)BArf (-) are effective catalysts for additions of β-ketoesters to RO2CN=NCO2R species (99-86% yields, 81-76% ee), which provide carbon-nitrogen bonds and valuable precursors to α-amino acids. PMID:27162946

  6. Werner syndrome as a hereditary risk factor for exocrine pancreatic cancer: potential role of WRN in pancreatic tumorigenesis and patient-tailored therapy.

    PubMed

    Chun, Stephen G; Yee, Nelson S

    2010-09-01

    Advanced age is considered a risk factor for pancreatic cancer, but this relationship at the molecular and genetic level remains unclear. We present a clinical case series focusing on an association between pancreatic adenocarcinoma and Werner syndrome (WS) that is an autosomal recessive genetic disorder characterized by accelerated aging and cancer predisposition, and is caused by loss-of-function mutations in the WS RecQ helicase gene (WRN). Although pancreatic adenocarcinoma mostly occurs in a sporadic fashion, a minority of cases occurs in the context of susceptible individuals with hereditary syndromes. While WS has not been previously recognized as a risk factor for developing malignant tumors of the exocrine pancreas, the clinicopathologic features of three reported patients suggest a contributory role of WRN deficiency in pancreatic carcinogenesis. Molecular genetic analyses support the role of WRN as a tumor suppressor gene, although recent evidence reveals that WRN can alternatively promote oncogenicity depending on the molecular context. Based upon the clinico-pathologic features of these patients and the role of WRN in experimental models, we propose that its loss-of-function predisposes the development of pancreatic adenocarcinoma through epigenetic silencing or loss-of-heterozygosity of WRN. To test this hypothesis, we are investigating the mechanistic role of WRN in pancreatic cancer models including a pancreatic adenocarcinoma cell line generated from a human with WS. These studies are expected to provide new insight into the relationship between aging and pancreatic tumorigenesis, and facilitate development of novel strategies for patient-tailored interventions in this deadly malignancy.

  7. ROVIBRATIONALLY RESOLVED DIRECT PHOTODISSOCIATION THROUGH THE LYMAN AND WERNER TRANSITIONS OF H{sub 2} FOR FUV/X-RAY-IRRADIATED ENVIRONMENTS

    SciTech Connect

    Gay, C. D.; Porter, R. L.; Stancil, P. C.; Abel, N. P.; Ferland, G. J.; Shaw, G.; Van Hoof, P. A. M.; Williams, R. J. R. E-mail: ryanlporter@gmail.com E-mail: npabel2@gmail.com E-mail: gargishaw@gmail.com E-mail: robin.williams@awe.co.uk

    2012-02-10

    Using ab initio potential curves and dipole transition moments, cross-section calculations were performed for the direct continuum photodissociation of H{sub 2} through the B{sup 1}{Sigma}{sup +}{sub u} <- X{sup 1}{Sigma}{sup +}{sub g} (Lyman) and C{sup 1}{Pi}{sub u} <- X{sup 1}{Sigma}{sup +}{sub g} (Werner) transitions. Partial cross-sections were obtained for wavelengths from 100 A to the dissociation threshold between the upper electronic state and each of the 301 bound rovibrational levels v''J'' within the ground electronic state. The resulting cross-sections are incorporated into three representative classes of interstellar gas models: diffuse clouds, photon-dominated regions, and X-ray-dominated regions (XDRs). The models, which used the CLOUDY plasma/molecular spectra simulation code, demonstrate that direct photodissociation is comparable to fluorescent dissociation (or spontaneous radiative dissociation, the Solomon process) as an H{sub 2} destruction mechanism in intense far-ultraviolet or X-ray-irradiated gas. In particular, changes in H{sub 2} rotational column densities are found to be as large as 20% in the XDR model with the inclusion of direct photodissociation. The photodestruction rate from some high-lying rovibrational levels can be enhanced by pumping from H Ly{beta} due to a wavelength coincidence with cross-section resonances resulting from quasi-bound levels of the upper electronic states. Given the relatively large size of the photodissociation data set, a strategy is described to create truncated, but reliable, cross-section data consistent with the wavelength resolving power of typical observations.

  8. Cobalt(III) Werner Complexes with 1,2-Diphenylethylenediamine Ligands: Readily Available, Inexpensive, and Modular Chiral Hydrogen Bond Donor Catalysts for Enantioselective Organic Synthesis

    PubMed Central

    2015-01-01

    In the quest for new catalysts that can deliver single enantiomer pharmaceuticals and agricultural chemicals, chemists have extensively mined the “chiral pool”, with little in the way of inexpensive, readily available building blocks now remaining. It is found that Werner complexes based upon the D3 symmetric chiral trication [Co(en)3]3+ (en = 1,2-ethylenediamine), which features an earth abundant metal and cheap ligand type, and was among the first inorganic compounds resolved into enantiomers 103 years ago, catalyze a valuable carbon–carbon bond forming reaction, the Michael addition of malonate esters to nitroalkenes, in high enantioselectivities and without requiring inert atmosphere conditions. The title catalysts, [Co((S,S)-dpen)3]3+ ((S,S)-33+) 3X–, employ a commercially available chiral ligand, (S,S)-1,2-diphenylethylenediamine. The rates and ee values are functions of the configuration of the cobalt center (Λ/Δ) and the counteranions, which must be lipophilic to solubilize the trication in nonaqueous media. The highest enantioselectivities are obtained with Λ and 2Cl–BArf–, 2BF4–BArf–, or 3BF4– salts (BArf– = B(3,5-C6H3(CF3)2)4–). The substrates are not activated by metal coordination, but rather by second coordination sphere hydrogen bonding involving the ligating NH2 groups. Crystal structures and NMR data indicate enthalpically stronger interactions with the NH moieties related by the C3 symmetry axis, as opposed to those related by the C2 symmetry axes; rate trends and other observations suggest this to be the catalytically active site. Both Λ- and Δ-(S,S)-33+ 2Cl–BArf– are effective catalysts for additions of β-ketoesters to RO2CN=NCO2R species (99–86% yields, 81–76% ee), which provide carbon–nitrogen bonds and valuable precursors to α-amino acids. PMID:27162946

  9. [Werner Leibbrand, Annemarie Wettley and controversies on "euthanasia" the background of medico-historical and ethical debates in the Post World War II era].

    PubMed

    Wiesinger, Christine; Frewer, Andreas

    2014-01-01

    Psychiatrists and medical historians Werner Leibbrand (1896 - 1974) and Annemarie Wettley (1913 - 1996) are amongst the most striking figures in the field of history of medicine. Leibbrand was appointed director of the "Heil- und Pflegeanstalt" in Erlangen shortly after the war. Fuelled by his own experiences of suppression and persecution during the Nazi era he promised to unearth the crimes and atrocities which had happened under watch of the Nazi regime. He was joined by Annemarie Wettley, who worked as a physician at the hospital and had developed an increasing interest in the history of medicine. In 1946 they published "Um die Menschenrechte der Geisteskranken" ("Human Rights of the Mentally Ill") about the "euthanasia" campaign of the Nazi regime. Although a number of substantial works followed, Leibbrand and Wettley failed to inform in more depth on crimes and atrocities, for instance killings of patients and forced malnutrition. Doubts and charges against Wettley regarding her role in dietary programmes at the Erlangen hospital and against Leibbrand regarding special expert's reports--both had a short-term arrest warrant--might have contributed to stagnation in their efforts. In 1953 Leibbrand accepted the offer of a chair at the University in Munich, Wettley followed and habilitated in history of medicine; in the year 1962 they married. Contacts and exchange amongst medico-historical experts shed light on developments during the post-war era; still, a critical and fundamental review of the crimes within the medical system of the Nazi regime did not take place during this time.

  10. A case of the higher-level classification of praying mantises (Mantodea) obscuring the synonymy of Majangella Giglio-Tos, 1915 (Liturgusidae, Liturgusinae) and Ephippiomantis Werner, 1922 (Hymenopodidae, Acromantinae).

    PubMed

    Svenson, Gavin J; Vollmer, William

    2014-01-01

    The praying mantis genus Majangella Giglio-Tos, 1915 is taxonomically treated with a re-description of the genus and the two included species, M. moultoni Giglio-Tos, 1915 and M. carli Giglio-Tos, 1915. The genus Ephippiomantis Werner, 1922 is newly determined to be the junior synonym of Majangella Giglio-Tos, 1915 based on morphology. The species for which the genus name Ephippiomantis was erected, E. ophirensis Werner, 1922, is re-described and now included within Majangella. This synonymy was determined herein as the direct result of erroneous higher-level placement of Majangella within the Majanginae by Giglio-Tos and was not recognized even after the genus was moved to within Liturgusidae. Action is now taken to move Majangella from within Liturgusidae to within the Hymenopodidae subfamily of Acromantinae, which is supported by morphological and molecular data. A key to the three species is provided along with habitus images, images of the head, pronotum, and foreleg, and illustrations of the male genitalia. Species distributions are presented and locality coordinates are provided in print as well as being available for download as a KML file viewable in Google Earth. PMID:24870860

  11. Genetics Home Reference: Werner syndrome

    MedlinePlus

    ... diabetes , diminished fertility, severe hardening of the arteries ( atherosclerosis ), thinning of the bones ( osteoporosis ), and some types ... most common causes of death are cancer and atherosclerosis. Related Information What does it mean if a ...

  12. Entanglement teleportation via werner states

    PubMed

    Lee; Kim

    2000-05-01

    Transfer of entanglement and information is studied for quantum teleportation of an unknown entangled state through noisy quantum channels. We find that the quantum entanglement of the unknown state can be lost during the teleportation even when the channel is quantum correlated. We introduce a fundamental parameter of correlation information which dissipates linearly during the teleportation through the noisy channel. Analyzing the transfer of correlation information, we show that the purity of the initial state is important in determining the entanglement of the replica state.

  13. [Two traditions in the scientific learning of the world. A case study of creation and reception of quantum mechanics over the period 1925-1927, on the bases of discussion between Werner Heisenberg and Albert Einstein].

    PubMed

    Krajniak, Wiktor

    2014-01-01

    The purpose of this article is the analyses of discussion between Albert Einstein and Werner Heisenberg in the period 1925-1927. Their disputes, relating to the sources of scientific knowledge, its methods and the value of knowledge acquired in this way, are part of the characteristic for the European science discourse between rationalism and empirism. On the basis of some sources and literature on the subject, the epistemological positions of both scholars in the period were reconstructed. This episode, yet poorly known, is a unique example of scientific disputes, whose range covers a broad spectrum of methodological problems associated with the historical development of science. The conducted analysis sheds some light on the source of popularity of logical empirism in the first half of the 20th century. A particular emphasis is placed on the impact of the neopositivist ideas which reflect Heisenberg's research program, being the starting point for the Copenhagen interpretation of quantum mechanics. The main assumption of logical empirism, concerning acquisition of scientific knowledge only by means of empirical procedures and logical analysis of the language of science, in view of the voiced by Einstein arguments, bears little relationship with actual testing practices in the historical aspect of the development of science. The criticism of Heisenberg's program, carried out by Einstein, provided arguments for the main critics of the neopositivist ideal and contributed to the bankruptcy of the idea of logical empirism, thereby starting a period of critical rationalism prosperity, arising from criticism of neopositivism and alluding to Einstein's ideas.

  14. Down regulation of miR-124 in both Werner syndrome DNA helicase mutant mice and mutant Caenorhabditis elegans wrn-1 reveals the importance of this microRNA in accelerated aging.

    PubMed

    Dallaire, Alexandra; Garand, Chantal; Paquel, Eric R; Mitchell, Sarah J; de Cabo, Rafael; Simard, Martin J; Lebel, Michel

    2012-09-01

    Small non-coding microRNAs are believed to be involved in the mechanism of aging but nothing is known on the impact of microRNAs in the progeroid disorder Werner syndrome (WS). WS is a premature aging disorder caused by mutations in a RecQ-like DNA helicase. Mice lacking the helicase domain of the WRN ortholog exhibit many phenotypic features of WS, including a pro-oxidant status and a shorter mean life span.Caenorhabditis elegans (C. elegans) with a nonfunctional wrn-1 DNA helicase also exhibit a shorter life span. Thus, both models are relevant to study the expression of microRNAs involved in WS. In this study, we show that miR-124 expression is lost in the liver of Wrn helicase mutant mice. Interestingly, the expression of this conserved miR-124 in whole wrn-1 mutant worms is also significantly reduced. The loss of mir-124 in C. elegans increases reactive oxygen species formation and accumulation of the aging marker lipofuscin, reduces whole body ATP levels and results in a reduction in life span. Finally, supplementation of vitamin C normalizes the median life span of wrn-1 and mir-124 mutant worms. These results suggest that biological pathways involving WRN and miR-124 are conserved in the aging process across different species.

  15. A specific mutation in the distant sonic hedgehog (SHH) cis-regulator (ZRS) causes Werner mesomelic syndrome (WMS) while complete ZRS duplications underlie Haas type polysyndactyly and preaxial polydactyly (PPD) with or without triphalangeal thumb.

    PubMed

    Wieczorek, Dagmar; Pawlik, Barbara; Li, Yun; Akarsu, Nurten A; Caliebe, Almuth; May, Klaus J W; Schweiger, Bernd; Vargas, Fernando R; Balci, Sevim; Gillessen-Kaesbach, Gabriele; Wollnik, Bernd

    2010-01-01

    Werner mesomelic syndrome (WMS) is an autosomal dominant disorder with unknown molecular etiology characterized by hypo- or aplasia of the tibiae in addition to the preaxial polydactyly (PPD) of the hands and feet and/or five-fingered hand with absence of thumbs. We show that point mutations of a specific nucleotide within the sonic hedgehog (SHH) regulatory region (ZRS) cause WMS. In a previously unpublished WMS family, we identified the causative G>A transition at position 404 of the ZRS, and in six affected family members of a second WMS family we found a 404G>C mutation of the ZRS. The 404G>A ZRS mutation is known as the "Cuban mutation" of PPD type II (PPD2). Interestingly, the index patient of that family had tibial hypoplasia as well. These data provide the first evidence that WMS is caused by a specific ZRS mutation, which leads to strong ectopic SHH expression. In contrast, we show that complete duplications of the ZRS region lead to type Haas polysyndactyly or triphalangeal thumb-polysyndactyly syndrome, but do not affect lower limb development. We suggest the term "ZRS-associated syndromes" and a clinical subclassification for the continuum of limb malformations caused by different molecular alterations of the ZRS.

  16. Hawking radiation, the Stefan-Boltzmann law, and unitarization

    NASA Astrophysics Data System (ADS)

    Giddings, Steven B.

    2016-03-01

    Where does Hawking radiation originate? A common picture is that it arises from excitations very near or at the horizon, and this viewpoint has supported the "firewall" argument and arguments for a key role for the UV-dependent entanglement entropy in describing the quantum mechanics of black holes. However, closer investigation of both the total emission rate and the stress tensor of Hawking radiation supports the statement that its source is a near-horizon quantum region, or "atmosphere," whose radial extent is set by the horizon radius scale. This is potentially important, since Hawking radiation needs to be modified to restore unitarity, and a natural assumption is that the scales relevant to such modifications are comparable to those governing the Hawking radiation. Moreover, related discussion suggests a resolution to questions regarding extra energy flux in "nonviolent" scenarios, that does not spoil black hole thermodynamics as governed by the Bekenstein-Hawking entropy.

  17. Stefan Jellinek (1871-1968): The only professor of electro-pathology.

    PubMed

    Jellinek, E H

    2016-08-01

    The exploding use of electricity in homes and industry in the second half of the 19th century was accompanied by many injuries and fatalities from electric currents. Their study by my father was the serendipitous outcome of his early work on possible blood pressure changes from electric currents in a career that started in internal medicine. It became his limited field of electro-pathology which embraced first aid, the care of the injured, histopathology and accident prevention. He was an enthusiastic teacher and collector of specimens, from tree trunks struck by lightning down to the microscopy of accidental and experimental electric lesions. PMID:24944049

  18. The 16th Werner Brandt Workshop on charged particle penetration phenomena

    SciTech Connect

    1996-05-01

    This report contains viewgraphs on the following topics: impact parameter dependence of charge transfer and energy loss; nonlinear dynamical response of the electron gas: comparison of some simple theories; stopping of ultrarelativistic ions in solids (33.2-TeV {sup 108}Pb); collective excitation in reduced dimensionality; collective states in atoms and cluster; plasmon coupling with external probes; atomic collisions with antiprotons; layer-number scaling in ultra-thin film stopping and energetics; atom-surface scattering under classical conditions; nonlinear effect of sweeping-out electrons in stopping power and electron emission in cluster impacts; electron emission from fast grazing collisions of ions with silicon surfaces; electron emission from ultra-thin carbon foils by kiV ions; Auger rates for highly charged ions in metals; Auger and plasmon assisted neutralization at surfaces; low energy (< 5eV) F{sup +} and F{sup -} ions transmission through condensed layers of water: enhancement and attenuation processes; charge transfer for H interacting with Al: atomic levels and linewidths; scattered projectile angular and charge state distributions for grazing collisions of multicharged ions with metal and insulator single crystal targets; the prolate hyperboloidat model in scanning probe microscopy; scanning probe microscopy of large biomolecules; microcantilever sensors; solution of the Fokker-Planck equation for electron transport using analytic spatial moments; and effective charge parametrization for z = 3-17 projectiles in composite targets.

  19. Extreme genetic diversity in the lizard Atlantolacerta andreanskyi (Werner, 1929): A montane cryptic species complex

    PubMed Central

    2012-01-01

    Background Atlantolacerta andreanskyi is an enigmatic lacertid lizard that, according to the most recent molecular analyses, belongs to the tribe Eremiadini, family Lacertidae. It is a mountain specialist, restricted to areas above 2400 m of the High Atlas Mountains of Morocco with apparently no connection between the different populations. In order to investigate its phylogeography, 92 specimens of A. andreanskyi were analyzed from eight different populations across the distribution range of the species for up to 1108 base pairs of mitochondrial DNA (12S, ND4 and flanking tRNA-His) and 2585 base pairs of nuclear DNA including five loci (PDC, ACM4, C-MOS, RAG1, MC1R). Results The results obtained with both concatenated and coalescent approaches and clustering methods, clearly show that all the populations analyzed present a very high level of genetic differentiation for the mitochondrial markers used and are also generally differentiated at the nuclear level. Conclusions These results indicate that A. andreanskyi is an additional example of a montane species complex. PMID:22946997

  20. Inelastic near-surface interactions. Proceedings of the Werner Brandt workshop

    SciTech Connect

    Not Available

    1985-04-01

    This workshop is one of an annual series covering penetration phenomena of charged particles in matter. This specific workshop includes electron scattering, ion and atom scattering, stopping powers, and cluster ion impacts on solids. Abstracts were prepared for individual items in the proceedings for inclusion in the data base. (GHT)

  1. [The importance of the phenomenom "imagination" in the scientific work of Werner Janzarik].

    PubMed

    Schmidt-Degenhard, M

    2004-10-01

    This paper in three parts and conclusion begins with the description of Janzarik's progression of thought, which originates in the narrowing of the gap between Jasper's descriptive phenomenology and anthropological phenomenology with its interpretive elements. Janzarik's structural-dynamic psychopathological approach has grown and differentiated from originally relatively narrow psychopathological questions to become an anthropology which aims to describe human assumptions concerning individual development/growth. The experience dimension is the focus, without suppressing interdisciplinary, objective findings, such as the inclusion of ethology. The mere clinical reconstruction of mental processes with all its heuristic risk was characterised by Janzarik as 'pure psychopathology'. In the section concerning structure and representation and their dependence on affect dynamic, we will emphasise the procedural nature of Janzarik's anthropology regarding developmental processes and its relationship to the philosopher Plessner's work in philosophy. The significance of the imagination in Janzarik's work contrasts to other philosophers who regard the imagination as ontological weakness, a deficiency, non-real, Janzarik, like Kant, sees the imagination as a constituent of reality. This will be exemplified in the characterisation of the mental field concerning the structural-dynamic model, the psychopathology of delusion as well as the oneiroid psychopathology. Finally the connection between autopraxis, Janzarik's core concept for the spontaneity of incidences and memory functions, and imagination will be described, which to a certain extent emphasises the working character of imagination for the flow of controlled mental activity. We will finish with the observation that Janzarik's work especially stresses experience and thus also the patient's individuality.

  2. Discussion of "Simple design criterion for residual energy on embankment dam stepped spillways" by Stefan Felder and Hubert Chanson

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Researchers from the University of Queensland of New South Wales provided guidance to designers regarding the hydraulic performance of embankment dam stepped spillways. Their research compares a number of high-quality physical model data sets from multiple laboratories, emphasizing the variability ...

  3. Writing Germany in Exile--The Bilingual Author as Cultural Mediator: Klaus Mann, Stefan Heym, Rudolf Arnheim and Hannah Arendt

    ERIC Educational Resources Information Center

    Jung, Verena

    2004-01-01

    This paper examines the process of self-translation undertaken by German exile writers who translated their own works, written in English, the language of their host country, back into their mother tongue, German. It postulates that the necessary precondition for self-translation is not just bilinguality but also biculturality and that it is this…

  4. Some trends of research in the domain of viral neuroinfections approached in the "Stefan S. Nicolau" Institute of Virology.

    PubMed

    Drăgănescu, N

    1985-01-01

    The main directions of research in the field of viral neuroinfections approached during 35 years in the Institute of Virology are briefly outlined. After some considerations on terminology and on the classification of viral encephalitides, mention is made of the studies in the domain of herpes infections, rabies, meningitis, encephalitis and slow virus infections of the central nervous system (subacute sclerosing panencephalitis, multiple sclerosis, amyotrophic lateral sclerosis, Creutzfeldt-Jakob disease, etc.).

  5. The master and the telescopes - the interplay between astronomy and optics in history (German Title: Der Meister und die Fernrohre - Das Wechselspiel zwischen Astronomie und Optik in der Geschichte)

    NASA Astrophysics Data System (ADS)

    Hamel, Jürgen; Keil, Inge

    The use of the telescope for astronomical observations since 1609 was one of the milestones in the celestial research. The contributions in this volume present new insights into the invention of the telescope and its relations to reading stones and spectacles, present investigations of special telescope types of early manufacturers, and analyze the telescopes of some historical observatories and the investigations carried out with them. Other contributions deal with the pictorial appearance of telescopes in baroque art, the connection of telescopes with photography, as well as the development of reflectors in the 20th century. The volume is dedicated to Rolf Riekher, an internationally established specialist ior the history of the telescope, on the occasion of his 85th birthday.

  6. Werner Complexes with ω-Dimethylaminoalkyl Substituted Ethylenediamine Ligands: Bifunctional Hydrogen-Bond-Donor Catalysts for Highly Enantioselective Michael Additions.

    PubMed

    Ghosh, Subrata K; Ganzmann, Carola; Bhuvanesh, Nattamai; Gladysz, John A

    2016-03-18

    The racemic carbonate complex [Co(en)2 O2 CO](+) Cl(-) (en=1,2-ethylenediamine) and (S)-[H3 NCH((CH2 )n NHMe2 )CH2 NH3 ](3+) 3 Cl(-) (n=1-4) react (water, charcoal, 100 °C) to give [Co(en)2 ((S)-H2 NCH((CH2 )n NHMe2 )CH2 NH2 )](4+) 4 Cl(-) (3 a-d H(4+) 4 Cl(-) ) as a mixture of Λ/Δ diastereomers that separate on chiral-phase Sephadex columns. These are treated with NaOH/Na(+) BArf (-) (BArf =B(3,5-C6 H3 (CF3 )2 )4 ) to give lipophilic Λ- and Δ-3 a-d(3+) 3 BArf (-) , which are screened as catalysts (10 mol %) for additions of dialkyl malonates to nitroalkenes. Optimal results are obtained with Λ-3 c(3+) 3 BArf (-) (CH2 Cl2 , -35 °C; 98-82 % yields and 99-93 % ee for six β-arylnitroethenes). The monofunctional catalysts Λ- and Δ-[Co(en)3 ](3+) 3 BArf (-) give enantioselectivities of <10 % ee with equal loadings of Et3 N. The crystal structure of Δ-3 a H(4+) 4 Cl(-) provides a starting point for speculation regarding transition-state assemblies. PMID:26918320

  7. VizieR Online Data Catalog: Tc IV, Tc V and Tc VI oscillator strengths (Werner+, 2015)

    NASA Astrophysics Data System (ADS)

    Werner, K.; Rauch, T.; Kucas, S.; Kruk, J. W.

    2015-01-01

    The discovery of technetium (Tc) in the atmospheres of red giants by Merrill (1952ApJ...116...21M) constituted convincing proof that s-process nucleosynthesis is indeed occurring in evolved stars. In principle, Tc should still be present in the atmospheres of hot post-AGB stars and (pre-) white dwarfs although, due to radioactive decay, it should be present in decreasing quantities along post-AGB evolution. The recent discovery of a large number of trans-iron group elements in hot white dwarfs with atomic numbers in the range A=30-56 (Zn to Ba) raises the prospect that Tc (A=43) may also be detected. However, this is currently not feasible because no atomic data exist for ionization stages beyond TcII. As an initial step, we calculated atomic energy levels and oscillator strengths of Tc IV-VI and used these data to compute non-local thermodynamic equilibrium (NLTE) model atmospheres to estimate at which minimum abundance level Tc could be detected. We show that Tc lines can be found in ultraviolet spectra of hot white dwarfs provided Tc is as abundant as other detected trans-Fe elements. We find that radiative levitation can keep Tc in large, easily detectable quantities in the atmosphere. A direct identification of Tc lines is still not feasible because wavelength positions cannot be computed with necessary precision. Laboratory measurements are necessary to overcome this problem. Our results suggest that such efforts are beneficial to the astrophysical community. (6 data files).

  8. Off the Beat. An Appreciation of Werner Heisenberg and Some Talk About How Physics Was in the Good Old Days

    ERIC Educational Resources Information Center

    Thomsen, Dietrick E.

    1976-01-01

    Presented is an insight into man's idea about physics and being a physicist in the days when Heisenberg, P. A. M. Dirac, Louis de Broglic and other famous physicists were young men. Heisenberg is compared to Newton, inventing new math as he needed it. Emphasis is placed on the fact that he was not a Nazi sympathizer. (EB)

  9. New media for classical coordination chemistry: phase transfer of Werner and related polycations into highly nonpolar fluorous solvents.

    PubMed

    Ghosh, Subrata K; Ojeda, Ann Sullivan; Guerrero-Leal, Juan; Bhuvanesh, Nattamai; Gladysz, John A

    2013-08-19

    Optimized procedures for the previously reported conversions of 1,3-diiodobenzene and perfluorohexyliodide (Rf6I; copper, DMSO, 140 °C) to 1,3-C6H4(Rf6)2 (3; 86-70%) and 3 to Br(3,5-C6H3(Rf6)2 (2; NBS, H2SO4/CF3CO2H; 88-75%) are described. The latter is converted (t-BuLi, BCl3) to the "fluorous BArf" salt NaB(3,5-C6H3(Rf6)2)4 (1 or NaBArf6; 77-70%), as given earlier. When orange aqueous solutions of [Co(en)3]Cl3 (en = ethylenediamine) are treated with perfluoro(methylcyclohexane) (PFMC) solutions of 1 (1:3 mol ratio), the aqueous phase decolorizes and [Co(en)3](BArf6)3 can be isolated from the fluorous phase (96%). Similar reactions with the trans-1,2-cyclohexanediamine analogue [Co(R,R-chxn)3]Cl3 and [Ru(bipy)3]Cl2 give [Co-(R,R-chxn)3](BArf6)3 (92%) and [Ru(bipy)3](BArf6)2 (95%). All of these salts are isolated as hydrates and exhibit toluene/PFMC partition coefficients of ≤1:≥99, establishing that the anion BArf6(-) can efficiently transport polar polycations into highly nonpolar fluorous phases. When equal volumes of CH2Cl2 and PFMC are charged with the "nonfluorous" BArf (B(3,5-C6H3-(CF3)2)4) salt [Co(en)3](BArf)3 and 3.0 equiv of the fluorous salt NaBArf6, the cobalt trication partitions predominantly into the fluorous phase (64:36). The arene 2 crystallizes in a polar space group (tetragonal, I4, Z = 8) with fluorous and nonfluorous domains and all eight bromine atoms located essentially on one face of the unit cell. PMID:23895404

  10. 78 FR 57178 - NASA Applied Sciences Advisory Committee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-17

    ...., Washington, DC 20546. FOR FURTHER INFORMATION CONTACT: Mr. Peter Meister, Science Mission Directorate, NASA...; citizenship; visa/green card information (number, type, expiration date); passport information...

  11. FAST TRACK COMMUNICATION: The Stefan Boltzmann law in a small box and the pressure deficit in hot SU(N) lattice gauge theory

    NASA Astrophysics Data System (ADS)

    Gliozzi, Ferdinando

    2007-05-01

    The blackbody radiation in a box L3 with periodic boundary conditions in thermal equilibrium at a temperature T is affected by finite-size effects. These bring about modifications of the thermodynamic functions which can be expressed in a closed form in terms of the dimensionless parameter LT. For instance, when LT ~ 4—corresponding to the value where the most reliable SU(N) gauge lattice simulations have been performed above the deconfining temperature Tc—the deviation of the free energy density from its thermodynamic limit is about 5%. This may account for almost half of the pressure deficit observed in lattice simulations at T ~ 4Tc.

  12. Synthesis, X-ray crystal structure and spectroscopy of a Werner-type host Co(II) complex, trans-bisisothiocyanatotetrakis( trans-4-styrylpyridine)cobalt(II)

    NASA Astrophysics Data System (ADS)

    Karunakaran, C.; Thomas, K. R. J.; Shunmugasundaram, A.; Murugesan, R.

    2000-05-01

    Single crystals of the title Co(II) complex, [Co(stpy) 4(NCS) 2] [stpy= trans-4-styrylpyridine] are prepared and characterized by elemental analysis, IR, and UV-visible spectroscopy and X-ray crystal structure determination. The complex crystallizes in the orthorhombic space group Pna2 1 with unit-cell parameters, a=32.058(3), b=15.362(5), c=9.818(5) Å, and Z=4. The structure consists of discrete monomeric units of [Co(stpy) 4(NCS) 2]. The equatorial positions of the Co(II) polyhedron are occupied by nitrogen atoms of the four stpy ligands and the axial positions are occupied by the nitrogen atoms of the two thiocyanate ions. The unit cell packing reveals interpenetration of styryl groups owing to conformational flexibility of phenyl and pyridyl rings in stpy ligands. Thus, it leads to efficient packing of the crystal lattice leaving no space available for guest inclusion. IR spectra reveal nitrogen coordination from stpy and terminal -NCS coordination of the thiocyanate group. The optical reflectance bands 475, 540 (shoulder) and 1022 nm suggest octahedral geometry in accordance with the X-ray data. However, the optical spectrum of acetonitrile solution shows an intense band at 615 nm and a weak shoulder at 570 nm suggesting participation of the solvent molecules in the coordination sphere. These bands indicate the presence of both tetrahedral and octahedral species in solution.

  13. ["My first encounter with German urology (1937)". Stefan Wesolowski (1908-2009) - a source in the archives of the German Society for Urology from the oldest corresponding member and promoter of Polish-German relationships].

    PubMed

    Moll, F H; Krischel, M; Zajaczkowski, T; Rathert, P

    2010-10-01

    A source in the archives of the German Society of Urology gives us a vivid insight into the situation in Berlin during the 1930s from the perspective of a young Polish doctor, and presents the situation at one of the leading urology institutions of the time in Germany. Furthermore, we learn about the social situation in hospitals as well as the discourse and networking taking place in the scientific community at that time.

  14. 76 FR 33758 - Granting of Request for Early Termination of the Waiting Period Under the Premerger Notification...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-09

    ... Equity Partners V, L.P. 05/13/2011 20110813 G Stefan Quandt; DataCard Corporation; Stefan Quandt... Silver Lake Partners III Cayman (AIV III), L.P.; Smart Modular Technologies (WWH), Inc.; Silver...

  15. Comment by J.P. Figueiredo, & Hoorn, C. on 'Late Miocene sedimentary environments in south-western Amazonia (Solimões Formation; Brazil)' by Martin Gross, Werner E. Piller, Maria Ines Ramos, Jackson Douglas da Silva Paz

    NASA Astrophysics Data System (ADS)

    Figueiredo, Jorge Jesus Picanço

    2012-04-01

    In their paper Gross et al., 2011 present an excellent description of a series of outcrops from the Eirunepe region in western Amazonia (Brazil). The authors interpret these sediments as relics of a Late Miocene anastomosing fluvial system and conclude that the paleogeography of the entire western Amazon region must have been characterized by this environmental setting. They also imply that therefore a long-lived lake system - or megawetland - never existed. We contend this assumption for some reasons, amongst them, the most important are: (1) this is an inconsistent overgeneralized conclusion; (2) The authors make references to previous scientific works we published which we consider incorrect, and therefore can mislead their readers.

  16. TOXICOLOGICAL HIGHLIGHT (REDOX REDUX: A CLOSER LOOK AT CONCEPTAL LOW MOLECULAR WEIGHT THIOLS)

    EPA Science Inventory

    Glutathione (GSH) is present as the most abundant low molecular weight thiol (LMWT) in virtually all mitochondria-bearing eucaryotic cells, often at millimolar concentrations (Meister, 1988). Functions of GSH include roles in DNA and protein synthesis, maintenance of cell membra...

  17. The Political Arithmetic of Cost-Effectiveness Analysis.

    ERIC Educational Resources Information Center

    Levin, Henry M.; And Others

    1986-01-01

    Responding to a critique of their earlier article, authors Levin and Meister, joined by Glass, attempt to clarify some of the issues and to correct implicit misunderstandings in the critique, while detailing the application of cost-effectiveness to educational interventions. Twenty footnotes are appended. (IW)

  18. Innovation for Strength. Proceedings of the Annual Accreditation and Quality Assurance Conference (Philadelphia, Pennsylvania, December 7-8, 1998).

    ERIC Educational Resources Information Center

    Commission on Higher Education, Philadelphia, PA. Middle States Association of Colleges and Schools.

    These proceedings of the annual accreditation and quality assurance conference present the following papers: "The Coming Revolution in Higher Education" (Arthur Levine); "Corporate/College Alliances" (Jeanne C. Meister); "Why Are We Educators?" (Catharine R. Stimpson); "Serving an Increasingly Adult Student Population: Lessons from Nordstrom and…

  19. Farmers' Cynicism toward Nature and Distrust of the Government: Where Does that Leave Conservation Buffer Programs?

    ERIC Educational Resources Information Center

    Gronewold, Katherine L.; Burnett, Ann; Meister, Mark

    2012-01-01

    Farmers are commonly regarded as stewards of the land. Farmers have, however, become cynical toward nature (Meister, Hest, & Burnett, 2009) and distrustful of the government (Cantrill, 2003). This study examines whether or not that cynicism and distrust is reflected in U.S. farmers' opinions of and future participation in conservation buffer…

  20. The Resolution of a Completely Inorganic Coordination Compound.

    ERIC Educational Resources Information Center

    Yasui, Takaji; And Others

    1989-01-01

    Discussed is a technique used by Alfred Werner to resolve inorganic coordination compounds. The materials, procedures and analysis necessary for undergraduates to repeat this procedure are described. (CW)

  1. The story of the Journal "Foaia Matematica" (80-years of the closing of the Journal "Foaia Matematica")

    NASA Astrophysics Data System (ADS)

    Gaina, A.

    2004-02-01

    A story of the Journal "Foaia Matematica", which issued in Basarabia during 1922-1924, is written. The scientific, technological and didactic interests of the organizers of the Journal (N.N. Codreanu, I. Apostolescu, Gh. Ganciu, I. Canitchi, Traian Maximoiu, Stefan R. Nicolae, Nicolae Profiri, Stefan Rapeanu, B. Goldenberg, Scarlat Panaitescu) are described.

  2. Of Big Hegemonies and Little Tigers: Ecocentrism and Environmental Justice

    ERIC Educational Resources Information Center

    Kopnina, Helen

    2016-01-01

    Stefan Bengtsson's commentary about policy hegemony discusses the alternative discourses of socialism, nationalism, and globalism. However, Stefan does not adequately demonstrate how these discourses can overcome the Dominant Western Worldview (DWW), which is imbued with anthropocentrism. It will be argued here that most policy choices promoting…

  3. Theories of Intelligence, Learning, and Motivation as a Basis for Praxis

    ERIC Educational Resources Information Center

    Nderu-Boddington, Eulalee

    2008-01-01

    This paper examines how Piaget, Werner, and Gardner differ regarding the roles of cognition, intelligence, and learning in the developmental process. Piaget believes in the predominance of genetic factors. Werner stresses the influence of biological factors, while Gardner proposes that the environment plays a greater influence in how intelligence…

  4. Clarification of the Hashin-Shtrikman bounds on the effective elastic moduli of polycrystals with hexagonal, trigonal, and tetragonal symmetries

    USGS Publications Warehouse

    Watt, J.P.; Peselnick, L.

    1980-01-01

    Bounds on the effective elastic moduli of randomly oriented aggregates of hexagonal, trigonal, and tetragonal crystals are derived using the variational principles of Hashin and Shtrikman. The bounds are considerably narrower than the widely used Voigt and Reuss bounds. The Voigt-Reuss-Hill average lies within the Hashin-Shtrikman bounds in nearly all cases. Previous bounds of Peselnick and Meister are shown to be special cases of the present results.

  5. Role of the superposition principle for enhancing the efficiency of the quantum-mechanical Carnot engine.

    PubMed

    Abe, Sumiyoshi; Okuyama, Shinji

    2012-01-01

    The role of the superposition principle is discussed for the quantum-mechanical Carnot engine introduced by Bender, Brody, and Meister [J. Phys. A 33, 4427 (2000)]. It is shown that the efficiency of the engine can be enhanced by the superposition of quantum states. A finite-time process is also discussed and the condition of the maximum power output is presented. Interestingly, the efficiency at the maximum power is lower than that without superposition.

  6. Living with Hearing Loss

    MedlinePlus

    ... Issues Special Section: Focus on Communication Living with Hearing Loss Past Issues / Fall 2008 Table of Contents ... family, including dad Bob, have adapted to her hearing impairment. Photo courtesy of Stefan Radtke, www.stefanradtke. ...

  7. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1982

    1982-01-01

    Describes: (1) an apparatus which provides a simple method for measuring Stefan's constant; (2) a simple phase shifting circuit; (3) a radioactive decay computer program (for ZX81); and (4) phase difference between transformer voltages. (Author/JN)

  8. Solid–Liquid Phase Change Driven by Internal Heat Generation

    SciTech Connect

    John Crepeau; Ali s. Siahpush

    2012-07-01

    This article presents results of solid-liquid phase change, the Stefan Problem, where melting is driven internal heat generation, in a cylindrical geometry. The comparison between a quasi-static analytical solution for Stefan numbers less than one and numerical solutions shows good agreement. The computational results of phase change with internal heat generation show how convection cells form in the liquid region. A scale analysis of the same problem shows four distinct regions of the melting process.

  9. Student Interns Tour Two NIH Facilities | Poster

    Cancer.gov

    Thirty-five Werner H. Kirsten student interns toured the National Library of Medicine and the National Institutes of Health Clinical Center in Bethesda in August to learn about the services and opportunities available.

  10. Recollections of Physics and of Physicists During the 1920's

    ERIC Educational Resources Information Center

    Dennison, David M.

    1974-01-01

    Presents the author's recollections of the emergence of the new quantum theory and his associations with such men as Oskar Klein, Niels Bohr, Frederick Hund, Werner Heisenberg, J. J. Thomson, and others. (GS)

  11. Why Extra Gauge Bosons Should Exist and How to Hunt Them

    NASA Astrophysics Data System (ADS)

    Leike, Arnd

    2003-09-01

    Werner Heisenberg's work is the foundation for many topics of present research. This is also true for the search for extra gauge bosons. The prospects of future colliders in this search are shortly mentioned.

  12. Colds and flus - antibiotics

    MedlinePlus

    Fashner J, Ericson K, Werner S. Treatment of the common cold in children and adults. Am Fam Physician. 2012; ... gov/pubmed/22962927 . Melio FR, Berge LR. Upper respiratory tract infections. In: Marx JA, Hockberger RS, Walls RM, et ...

  13. In-Vitro Immunology - Skylab Student Experiment ED-31

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This chart describes the Skylab student experiment In-Vitro Immunology, proposed by Todd A. Meister of Jackson Heights, New York. He suggested an in-vitro observation of the effects of zero-gravity on a presipitin-type antigen-antibody reaction, as compared with the same reaction carried out in an Earth-based laboratory. In March 1972, NASA and the National Science Teachers Association selected 25 experiment proposals for flight on Skylab. Science advisors from the Marshall Space Flight Center aided and assisted the students in developing the proposals for flight on Skylab.

  14. A finite element model for ice ball evolution in a multi-probe cryosurgery.

    PubMed

    Liu, Zhihong; Muldrew, Ken; Wan, Richard; Rewcastle, John

    2003-06-01

    The ice formation in a water body is examined for the computation of temperature field, phase change and a moving ice-water interface whose location is not known á priori. This is classically referred to as the Stefan problem [Rubinstein, L.I. (1971) The Stefan Problem (American Mathematical Society, Providence, Rhode Island 02904]. Based on the Duvaut [Duvaut, G. (1973) "Résolution d'un probléme Stefan" C.R. Acad Sci. Paris 276, 1461-1463] transformation, the governing equations for heat conduction are formulated within a variational principle that is readily amenable to a standard finite element solution without remeshing. Numerical simulation results pertaining to the freezing of tumour tissue in a multi-cryoprobe cryosurgery are presented. These results lend both quantitative and graphical support to the current empirical standards of "effective therapy" in view of refining clinical applications.

  15. [Jesuits Chemists of Hapsburg Monarchy].

    PubMed

    Južnič, Stanislav

    2016-01-01

    The achievements of the Jesuits from the Austrian and Bohemian provinces, who have published books on chemistry are focused. Their links with the area of today's Slovenia are particularly exposed. The guidelines which have enabled prompt victories of the ideas about the structure of matter of Jesuit Ru|er Bokovi are indicated. Inconceivable fast spread of Bošković's adherents in the Hapsburg monarchy is compared with a similar rapid introduction of the kinetic theories of atoms of Slovene Jožef Stefan and Ludwig Boltzmann in the same geographical area. Boltzmann was not only Stefan's best student, but he also married a half Slovenian maid. PMID:27333568

  16. [Jesuits Chemists of Hapsburg Monarchy].

    PubMed

    Južnič, Stanislav

    2016-01-01

    The achievements of the Jesuits from the Austrian and Bohemian provinces, who have published books on chemistry are focused. Their links with the area of today's Slovenia are particularly exposed. The guidelines which have enabled prompt victories of the ideas about the structure of matter of Jesuit Ru|er Bokovi are indicated. Inconceivable fast spread of Bošković's adherents in the Hapsburg monarchy is compared with a similar rapid introduction of the kinetic theories of atoms of Slovene Jožef Stefan and Ludwig Boltzmann in the same geographical area. Boltzmann was not only Stefan's best student, but he also married a half Slovenian maid.

  17. Multicomponent diffusion in polymeric liquids.

    PubMed Central

    Curtiss, C F; Bird, R B

    1996-01-01

    It is shown how the phase-space kinetic theory of polymeric liquid mixtures leads to a set of extended Maxwell-Stefan equations describing multicomponent diffusion. This expression reduces to standard results for dilute solutions and for undiluted polymers. The polymer molecules are modeled as flexible bead-spring structures. To obtain the Maxwell-Stefan equations, the usual expression for the hydrodynamic drag force on a bead, used in previous kinetic theories, must be replaced by a new expression that accounts explicitly for bead-bead interactions between different molecules. PMID:11607693

  18. The Nudity of the Ego. An Eckhartian Perspective on the Levinas/Derrida Debate on Alterity

    PubMed Central

    Roesner, Martina

    2016-01-01

    ABSTRACT The present paper examines the Eckhartian motives in Derrida's critique of Levinas’ concept of the “Other”. The focus is put on the Husserlian concept of alter ego that is at the core of the debate between Levinas and Derrida. Against Levinas, Derrida argues that alter is not an epithet that expresses a mere accidental modification of the ego, but an indicator of radical exteriority. Interestingly enough, this position is virtually identical with Meister Eckhart's interpretation of the famous proposition from Exodus 3:14 “I am who I am”. Eckhart claims that the pronoun ego denotes the absolutely simple substance of the uncreated intellect, which can, by definition, never receive any accidental determination whatsoever. The reduplication of the “I am” is by no means tautological, but expresses the intra-divine dynamic of the Father who engenders the Son as his perfect equal and alter ego. This transcendental conception of egoity also governs the relationships between human beings: the ethical encounter with the “Other” requires that we consider them not primarily in their empirical, contingent existence but in the transcendental purity of their indeclinable ego, which is identical with the incessant act in which God knows himself in the Son as his absolutely Other. Thus, Meister Eckhart's approach proves, against Levinas, that it is possible to develop an “egological” philosophy that avoids the pitfalls of a naturalistic and potentially violent ontology of the subject. PMID:27152029

  19. Race and Repression in a Dance Routine: A Response to Ramaekers and Vlieghe

    ERIC Educational Resources Information Center

    Standish, Paul

    2015-01-01

    Stefan Ramaekers and Joris Vlieghe's "Infants, childhood and language in Agamben and Cavell: education as transformation" is an insightful discussion of an important facet of educational experience. In the article, they consider a Fred Astaire dance sequence from the 1953 Vincente Minnelli film, "The Band Wagon," in combination…

  20. Teaching as a Reflective Practice: The German Didaktik Tradition. Studies in Curriculum Theory Series.

    ERIC Educational Resources Information Center

    Westbury, Ian, Ed.; Hopmann, Stefan, Ed.; Riquarts, Kurt, Ed.

    This collection of papers presents essays by German scholars and practitioners writing from within the German Didaktik tradition and interpretive essays by U.S. scholars. After an introduction, "Starting a Dialogue: A Beginning Conversation between Didaktik and the Curriculum Traditions" (Stefan Hopmann and Kurt Riquarts), there are 18 chapters in…

  1. Language Crossings: Negotiating the Self in a Multicultural World. Language and Literacy Series.

    ERIC Educational Resources Information Center

    Ogulnick, Karen, Ed.

    This book includes 25 papers in 5 parts. Part 1, "Dislocations," includes (1) "Puzzle" (Myrna Nieves); (2) "No Language To Die In" (Greta Hofmann Nemiroff); (3) "Here's Your Change 'N Enjoy the Show" (Verena Stefan); (4) "The Vagabond Years" (Elizabeth Dykman); (5) "From Bayamon to Brooklyn" (Rita E. Negron Maslanek); (6) "Writing for Effect"…

  2. Quantized space-time and its influence on two physical problems

    NASA Astrophysics Data System (ADS)

    Ma, Meng-Sen; Zhao, Hui-Hua

    2014-04-01

    Based on Snyder's idea of quantized space-time, we derive a new generalized uncertainty principle and new modified density of states. Accordingly, we discuss the influence of the modified generalized uncertainty principle on the black hole entropy and the influence of the modified density of states on the Stefan-Boltzman law.

  3. "Neverwinter Nights" in Alberta: Conceptions of Narrativity through Fantasy Role-Playing Games in a Graduate Classroom

    ERIC Educational Resources Information Center

    Gouglas, Sean; Sinclair, Stefan; Ellefson, Olaf; Sharplin, Scott

    2006-01-01

    Most humanities courses rarely require students to create the kinds of work they are studying. Sean Gouglas, Stefan Sinclair, Olaf Ellefson, and Scott Sharplin outline the value of this rare experience by describing an assignment in their graduate humanities computing course in which students examined hypermedia narratives by authoring a…

  4. Figures of Disengagement: Charles Taylor, Scientific Parenting, and the Paradox of Late Modernity

    ERIC Educational Resources Information Center

    Van den Berge, Luc; Ramaekers, Stefan

    2014-01-01

    In this essay Luc Van den Berge and Stefan Ramaekers take the idea(l) of "scientific parenting" as an example of ambiguities that are typical of our late-modern condition. On the one hand, parenting seems like a natural thing to do, which makes "scientific parenting" sound like an oxymoron; on the other hand, a disengaged…

  5. On Blackbody Radiation.

    ERIC Educational Resources Information Center

    Jain, Pushpendra K.

    1991-01-01

    The interrelationship between the various forms of the Planck radiation equation is discussed. A differential equation that gives intensity or energy density of radiation per unit wavelength or per unit frequency is emphasized. The Stefan-Boltzmann Law and the change in the glow of a hot body with temperature are also discussed. (KR)

  6. Fibrin polymerization as a phase transition wave: A mathematical model

    NASA Astrophysics Data System (ADS)

    Lobanov, A. I.

    2016-06-01

    A mathematical model of fibrin polymerization is described. The problem of the propagation of phase transition wave is reduced to a nonlinear Stefan problem. A one-dimensional discontinuity fitting difference scheme is described, and the results of one-dimensional computations are presented.

  7. Ruling Relationships in Sustainable Development and Education for Sustainable Development

    ERIC Educational Resources Information Center

    Berryman, Tom; Sauvé, Lucie

    2016-01-01

    It is from historical perspectives on more than 40 years of environment related education theories, practices, and policies that we revisit what might otherwise become a tired conversation about environmental education and sustainable development. Our contemporary critical analysis of Stefan Bengtsson's research about policy making leads us to…

  8. Simulation of laser melting and evaporation of superconducting ceramics

    SciTech Connect

    Mazhukin, V. . Inst. of Mathematical Modeling); Smurov, I. ); Dupuy, C. . Inst. de Science et de Genie des Materiaux et Procedes); Jeandel, D. )

    1994-11-01

    The peculiarities of pulsed laser melting and evaporation of the superconducting ceramics are analyzed by means of numerical simulation. The appearance of the overheated metastable states in solid and liquid phases is shown as a result of the phase front dynamics and volume nature of laser energy release. A method of dynamic adaptation for the multifront Stefan problem is proposed.

  9. Blackbody Radiation from an Incandescent Lamp

    ERIC Educational Resources Information Center

    Ribeiro, C. I.

    2014-01-01

    In this article we propose an activity aimed at introductory students to help them understand the Stefan-Boltzmann and Wien's displacement laws. It only requires simple materials that are available at any school: an incandescent lamp, a variable dc energy supply, and a computer to run an interactive simulation of the blackbody spectrum.…

  10. The drop heard round the world

    NASA Astrophysics Data System (ADS)

    Bergin, Shane D.; Hutzler, Stefan; Weaire

    2014-05-01

    When physicists at Trinity College Dublin began looking after an antique funnel full of pitch, they had no idea their humble experiment would spawn one of 2013's most “viral” news stories. Shane D Bergin, Stefan Hutzler and Denis Weaire reflect on the value of “slow science” to a hyper-connected, social-media world.

  11. A World Where All Worlds Cohabit

    ERIC Educational Resources Information Center

    Teamey, Kelly; Mandel, Udi

    2016-01-01

    In response to Stefan Bengtsson's search for alternatives to Education for Sustainable Development practices outside the mainstream of the state and its policy formulations, this response outlines how our journey, experiences, and approaches reflect a de-professionalizing encounter with autonomous places of learning emerging from indigenous…

  12. Probing Planck's Law at Home

    ERIC Educational Resources Information Center

    Bonnet, I.; Gabelli, J.

    2010-01-01

    We report on the physics around an incandescent lamp. Using a consumer-grade digital camera, we combine electrical and optical measurements to explore Planck's law of black-body radiation. This simple teaching experiment is successfully used to measure both Stefan's and Planck's constants. Our measurements lead to a strikingly accurate value for…

  13. Ice-­Ocean Thermodynamic Interface and Small-­Scale Issues

    SciTech Connect

    Turner, Adrian K.

    2012-07-02

    This presentation discusses: (1) Stefan condition, (2) lower boundary condition of mushy layers, (3) salt flux to ocean from gravity drainage, (4) distribution of salt flux in the ocean, (5) under ice melt ponds and false bottoms, and (6) basal ablation.

  14. On a Heuristic Point of View About Inertial Deconfinement of Quarks

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2009-05-01

    I propose a novel heuristic method for the deconfinement of quarks. It proceeds in two phases. Firstly, a frozen hydrogen pellet is inertially confined by the ultra-intense lasers up to a solid state density. Secondly, a solid state nano-pellet is ``punched'' by a femtosecond TeV-photon beam created in the beat wave driven free electron laser (BW-FEL), leading to the ``rapture'' (in a ``karate chop'' model) of the ``MIT Bag'' before the asymptotically free quarks move apart. The threshold ``rapture force'' of the TeV photon is 10^8N. M. Gell-Mann. The Quark and the Jaguar: Adventures in the Simple and the Complex (New York, NY: W.H. Freeman and Co., 1994) [cf. M. Gell-Mann, The Garden of Live Flowers in: V. Stefan (Editor), Physics and Society. Essays Honoring Victor Frederick Weisskopf (Springer, 1998), pp. 109-121]. V. Alexander Stefan. Beat Wave Driven Free Electron Laser (S-U-Press, 2002, La Jolla, CA)[cf. V. Stefan et. al., Bull. Am. Phys. Soc. 32, No. 9, 1713 (1987)] J. I. Friedman and H. Kendall, Viki, in: V. Stefan (Editor), Physics and Society. Essays Honoring Victor Frederick Weisskopf (Springer, 1998), pp. 103-108].

  15. Democracy and Education in the Twenty-First Century: Deweyan Pragmatism and the Question of Racism

    ERIC Educational Resources Information Center

    Neubert, Stefan

    2010-01-01

    Why is John Dewey still such an important philosopher today? Writing from the perspective of the Cologne Program of Interactive Constructivism, Stefan Neubert tries in what follows to give one possible answer to this question. Neubert notes that Cologne constructivism considers Dewey in many respects as one of the most important predecessors of…

  16. Reconstructing Deweyan Pragmatism: A Review Essay

    ERIC Educational Resources Information Center

    Neubert, Stefan

    2009-01-01

    In this essay Stefan Neubert argues that John Dewey was a philosopher of reconstruction and that the best use we can make of him today is to reconstruct his work in and for our own contexts. Neubert distinguishes three necessary and equally important components of the overall project of reconstructing Deweyan pragmatism: first, to make strong and…

  17. Finding Truth in "Lies": Nietzsche's Perspectivism and Its Relation to Education

    ERIC Educational Resources Information Center

    Jonas, Mark E.; Nakazawa, Yoshiaki M.

    2008-01-01

    In his 2001 article "Teaching to Lie and Obey: Nietzsche on Education", Stefan Ramaekers defends Nietzsche's concept of perspectivism against the charge that it is relativistic. He argues that perspectivism is not relativistic because it denies the dichotomy between the "true" world and the "seeming" world, a dichotomy central to claims to…

  18. The 2014 Nobel Prize in Chemistry: a large-scale prize for achievements on the nanoscale.

    PubMed

    Choquet, Daniel

    2014-12-17

    The 2014 Nobel Prize in Chemistry awarded to Eric Betzig, Stefan W. Hell, and William E. Moerner "for the development of superresolved fluorescence microscopy" can be seen as a combined prize for single-molecule detection and superresolution imaging. Neurons, arguably the most morphologically complex cell type, are the subject of choice for this application, now generically called "nanoscopy."

  19. Aporias, Politics of Ontology, Ethics, and "We"?

    ERIC Educational Resources Information Center

    Bengtsson, Stefan Lars

    2016-01-01

    The different responses, interpretations, and consequent critiques of Stefan Lars Bengtsson's "Hegemony and the Politics of Policy Making for Education for Sustainable Development" highlight how the various critical outlooks are framed by, seemingly, incommensurable positions, or figures of reasoning, that inform their thinking.…

  20. The 2014 Nobel Prize in Chemistry: a large-scale prize for achievements on the nanoscale.

    PubMed

    Choquet, Daniel

    2014-12-17

    The 2014 Nobel Prize in Chemistry awarded to Eric Betzig, Stefan W. Hell, and William E. Moerner "for the development of superresolved fluorescence microscopy" can be seen as a combined prize for single-molecule detection and superresolution imaging. Neurons, arguably the most morphologically complex cell type, are the subject of choice for this application, now generically called "nanoscopy." PMID:25521373

  1. Time to Reframe Politics and Practices in Correctional Education

    ERIC Educational Resources Information Center

    LoBuglio, Stefan

    2001-01-01

    In this chapter, Stefan LoBuglio discusses the politics and practices of educational programs for adults in correctional facilities. To begin, LoBuglio provides an overview of the field of corrections, including various types of facilities and correctional programs, as well as demographic and educational data on the U.S. incarcerated population…

  2. Flight experiment on acousto-optic crystal growth

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Duval, Walter M. B.

    1991-01-01

    The physical vapor transport method was used for growing mercurous chloride crystals in different convective conditions. Optical homogeneity is found to be extremely dependent on convection levels. Results of numerical studies indicate that for a gravity level of 0.001 g or less the Stefan wind drives the flow and no recirculating cells are observed.

  3. Graphic Novels in the Classroom

    ERIC Educational Resources Information Center

    Martin, Adam

    2009-01-01

    Today many authors and artists adapt works of classic literature into a medium more "user friendly" to the increasingly visual student population. Stefan Petrucha and Kody Chamberlain's version of "Beowulf" is one example. The graphic novel captures the entire epic in arresting images and contrasts the darkness of the setting and characters with…

  4. Losing Traction and the Art of Slip-Sliding Away: Or, Getting over Education for Sustainable Development

    ERIC Educational Resources Information Center

    Jickling, Bob

    2016-01-01

    This response problematizes Stefan Bengtsson's (2016) defense of education for sustainable development. He argues that sustainable development and education for sustainable development are not globalizing and hegemonic discourses, as some have claimed, and uses case-study analysis of Vietnamese policy documents to support his claims. He observes…

  5. The Invisible University? Lifelong Learning, Literary Study and the City of Bristol

    ERIC Educational Resources Information Center

    Sperlinger, Tom

    2012-01-01

    This article explores why some universities may be "invisible" to adults in their local communities. It suggests that funding changes in UK higher education, particularly those initiated by the Browne Review in 2010, may reinforce such a divide. The article draws on Stefan Collini's critiques of government policy, particularly in relation to the…

  6. Pulsed electric field processing for fruit and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This month’s column reviews the theory and current applications of pulsed electric field (PEF) processing for fruits and vegetables to improve their safety and quality. This month’s column coauthor, Stefan Toepfl, is advanced research manager at the German Institute of Food Technologies and professo...

  7. Adding Albedo and Atmospheres

    ERIC Educational Resources Information Center

    LoPresto, Michael C.

    2013-01-01

    In a previous article in this journal, we reported on a laboratory activity in which students used a derivation from the Stefan-Boltzmann law to calculate planetary temperatures and compare them to measured values from various (mostly online) sources. The calculated temperatures matched observed values very well with the exceptions of Venus and…

  8. Numerical study on freezing heat transfer in water-saturated porous media

    SciTech Connect

    Sasaki, A.; Aiba, S. ); Fukusako, S. )

    1990-01-01

    Numerical investigations have been carried out to examine the characteristics of unsteady freezing heat transfer in water-saturated porous media. Also, the effects of Stefan number and of the ratio if cooling to heating temperature are discussed for the unsteady freezing heat transfer.

  9. EDITORIAL: Focus on Cloaking and Transformation Optics

    NASA Astrophysics Data System (ADS)

    Leonhardt, Ulf; Smith, David R.

    2008-11-01

    multi-frequency cloaking Andrea Alù and Nader Engheta Electromagnetic cloaking devices for TE and TM polarizations Filiberto Bilotti, Simone Tricarico and Lucio Vegni An aberration-free lens with zero F-number D Schurig Transformational optics of plasmonic metamaterials I I Smolyaninov An acoustic metafluid: realizing a broadband acoustic cloak J B Pendry and Jensen Li On the possibility of metamaterial properties in spin plasmas G Brodin and M Marklund A homogenization route towards square cylindrical acoustic cloaks Mohamed Farhat, Sébastien Guenneau, Stefan Enoch, Alexander Movchan, Frédéric Zolla and André Nicolet Transformation optics: approaching broadband electromagnetic cloaking A V Kildishev, W Cai, U K Chettiar and V M Shalaev Generalized field-transforming metamaterials Sergei A Tretyakov, Igor S Nefedov and Pekka Alitalo Electromagnetic beam modulation through transformation optical structures Xiaofei Xu, Yijun Feng and Tian Jiang Superantenna made of transformation media Ulf Leonhardt and Tomáš Tyc Material parameters and vector scaling in transformation acoustics Steven A Cummer, Marco Rahm and David Schurig Isotropic transformation optics: approximate acoustic and quantum cloaking Allan Greenleaf, Yaroslav Kurylev, Matti Lassas and Gunther Uhlmann Transformation optical designs for wave collimators, flat lenses and right-angle bends Do-Hoon Kwon and Douglas H Werner Alternative derivation of electromagnetic cloaks and concentrators A D Yaghjian and S Maci Solutions in folded geometries, and associated cloaking due to anomalous resonance Graeme W Milton, Nicolae-Alexandru P Nicorovici, Ross C McPhedran, Kirill Cherednichenko and Zubin Jacob Finite wavelength cloaking by plasmonic resonance N-A P Nicorovici, R C McPhedran, S Enoch and G Tayeb

  10. PREFACE: Selected contributions from the 3rd Theory Meets Industry International Workshop, TMI2009 (Nagoya, Japan, 11-13 November 2009) Selected contributions from the 3rd Theory Meets Industry International Workshop, TMI2009 (Nagoya, Japan, 11-13 November 2009)

    NASA Astrophysics Data System (ADS)

    Tanaka, Isao; Hafner, Jürgen; Wimmer, Erich; Asahi, Ryoji

    2010-09-01

    . Lectures and poster presentations were thus solicited from leading international academic and industrial researchers. The large audience that attended responded to the high quality of the talks with pertinent questions and lively discussions. The third workshop, TMI2009, was held over three days from 11-13 November, 2009, at the Nagoya International Center, Nagoya, Japan. Invited talks were given by 23 speakers from 9 countries from both the academic and industry sectors. The speakers were Ryoji Asahi (Toyota Central R&D Labs, Japan), Tomas Bucko (University of Vienna, Austria), Gábor Csányi (University of Cambridge, UK), Alessandro De Vita (King's College London, UK), Bernard Delley (Paul Scherrer Institute, Switzerland), Christophe Domain (EDF, France), George Fitzgerald (Accelrys, USA), Takeo Fujiwara (University of Tokyo, Japan), Jürgen Hafner (University of Vienna, Austria), Masaya Ishida (Sumitomo Chemicals, Japan), Werner Janse Van Rensburg (Sasol Technology, South Africa), Masanori Kohyama (AIST, Japan), Takao Kotani (Tottori University, Japan), Georg Kresse (University of Vienna, Austria), Katsuyuki Matsunaga (Kyoto University, Japan), Stefan Müller (University of Erlangen-Nuremberg, Germany), Shin-ichiro Nakamura (Mitsubishi Chemicals, Japan), Fumiyasu Oba (Kyoto University, Japan), Tamio Oguchi (Hiroshima University, Japan), Pascal Raybaud (IFP, France), Isao Tanaka (Kyoto University/JFCC, Japan), Göran Wahnström (Chalmers University of Technology, Sweden), and Erich Wimmer (Materials Design Inc., USA). There were 40 poster presentations in total. The workshop was attended by approximately 120 participants with approximately 50 per cent from industry. The invited talks covered advances in ab initio solid-state calculations and their practical use in industry. Presentations outlining the progress made in treating large and complex systems, as well as more accurate and efficient calculation methods, were given from the theory side. Examples of the use of ab

  11. The Logarithmic-to-Linear Shift: One Learning Sequence, Many Tasks, Many Time Scales

    ERIC Educational Resources Information Center

    Siegler, Robert S.; Thompson, Clarissa A.; Opfer, John E.

    2009-01-01

    The relation between short-term and long-term change (also known as learning and development) has been of great interest throughout the history of developmental psychology. Werner and Vygotsky believed that the two involved basically similar progressions of qualitatively distinct knowledge states; behaviorists such as Kendler and Kendler believed…

  12. How Great Is Your Student Intern? | Poster

    Cancer.gov

    Editor’s note: We asked Werner H. Kirsten Student Internship Program (WHK SIP) mentors to tell us about the unique and diverse backgrounds of some of this year’s student interns. Alex Beall Microarray Group, Genomics Laboratory, Cancer Research Technology Program Mentors: Nicole Shrader and Stephanie Mellott, research associates

  13. Diagnostic Accuracy of the Structured Photographic Expressive Language Test: Third Edition (SPELT-3)

    ERIC Educational Resources Information Center

    Perona, Kristen; Plante, Elena; Vance, Rebecca

    2005-01-01

    Purpose: This study examined the empirical evidence for using the Structured Photographic Expressive Language Test: Third Edition (SPELT-3; Dawson, Stout, & Eyer, 2003) to diagnose language impairment in preschool children. The SPELT-3 is a revision of the SPELT-II (Werner & Kresheck, 1983), which has been proven in the past to have high levels of…

  14. Qualifications for a Changing World.

    ERIC Educational Resources Information Center

    Vocational Training, 1991

    1991-01-01

    This theme issue focuses on skills and qualifications in future world markets in general and in the Single Market within the European Community (EC). The first two articles are "Anthropocentric Production Systems: Advanced Manufacturing is Based on Skilled People" (Werner Wobbe) and "New Skills or a New Concept of 'the Job'"? (Enrique Retuerto de…

  15. 75 FR 71033 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... Linden (215) 814-2096, Region IV--Lynorae Benjamin (404) 562-9040, Region V--Andy Chang (312) 886-0258.... 2023, (617) 918-1661. Raymond Werner, Chief, Air Programs New Jersey, New York, Puerto Branch, EPA... Agency FR Federal Register FRM Federal Reference Method IQ Intelligence Quotient NAAQS National...

  16. Tunable spatial decoherers for polarization-entangled photons.

    PubMed

    Puentes, Graciana; Voigt, Dirk; Aiello, Andrea; Woerdman, J P

    2006-07-01

    We report a novel controllable source of spatial decoherence for twin photons, based upon commercially available wedge depolarizers. This allows us to convert the polarization-entangled singlet state into a tunable mixed state. A full characterization of this mixed state, by means of quantum tomography, shows that such a spatial decoherer can be used for synthesizing Werner-like states on demand.

  17. 77 FR 68775 - Notice of Proposed Administrative Settlement Pursuant to the Comprehensive Environmental Response...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-16

    ... public inspection at 1445 Ross Avenue, Dallas, Texas 75202-2733. DATES: Comments must be submitted on or... relating to the settlement are available for public inspection at 1445 Ross Avenue, Dallas, Texas 75202-2733. A copy of the proposed settlement may be obtained from Robert Werner at 1445 Ross Avenue,...

  18. 77 FR 13125 - Proposed Administrative Settlement Pursuant to the Comprehensive Environmental Response...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-05

    .... The Agency's response to any comments received will be available for public inspection at 1445 Ross... for public inspection at 1445 Ross Avenue Dallas, Texas 75202-2733. A copy of the proposed settlement may be obtained from Robert Werner, Enforcement Officer, 1445 Ross Avenue, Dallas, Texas 75202-2733...

  19. 75 FR 49914 - Meeting of the Independent Panel To Review the Judge Advocate Requirements of the Department of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-16

    ... to the public, subject to the availability of space. In keeping with the spirit of FACA, the Panel welcomes written comments concerning its work from the public at any time. Interested citizens are... for consideration by the Panel at any time prior to August 23, 2010. D. J. Werner,...

  20. More than Talk: Relations between Emotion Understanding and Positive Behaviour in Toddlers

    ERIC Educational Resources Information Center

    Ensor, Rosie; Hughes, Claire

    2005-01-01

    Background. Associations between positive behaviour, emotion understanding and verbal ability have been reported in studies of preschoolers (Cassidy, Werner, Rourke, Zubernis, & Balaraman, 2003), but have yet to be investigated in younger children. Methods. In this study the performance of 36 toddlers (17 boys and 19 girls; mean age = 29 months,…

  1. Distinguishing between Development and Change: Reviving Organismic-Developmental Theory

    ERIC Educational Resources Information Center

    Raeff, Catherine

    2011-01-01

    The goal of this paper is to contribute to the revival of Heinz Werner's organismic-developmental theory by considering some of its key claims in relation to contemporary developmental theory and research. The organismic-developmental definition of development in terms of differentiation and integration is first discussed in relation to…

  2. 75 FR 43892 - Approval and Promulgation of Implementation Plans; New York Prevention of Significant...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-27

    ... Broadway, 25th Floor, New York, New York 10007-1866. Hand Delivery: Raymond Werner, Chief, Air Programs..., regarding the Clean Air Act's PSD and Nonattainment New Source Review (NNSR) programs. 67 FR 80186... designated the New York City metropolitan area as nonattainment for the PM 2.5 standard (70 FR 944)....

  3. The Physics of "Copenhagen" for Students and the General Public.

    ERIC Educational Resources Information Center

    Bergstrom, L.; Johansson, K. E.; Nilsson, Ch.

    2001-01-01

    The play Copenhagen has attracted the attention of a large audience in several countries. The hypothetical discussion between two of the giants in physics, Niels Bohr and Werner Heisenberg, has inspired us to start a theoretical and experimental exploration of quantum physics. This theme has been used in Stockholm Science Laboratory for audiences…

  4. The "Hard Problem" and the Quantum Physicists. Part 1: The First Generation

    ERIC Educational Resources Information Center

    Smith, C. U. M.

    2006-01-01

    All four of the most important figures in the early twentieth-century development of quantum physics--Niels Bohr, Erwin Schroedinger, Werner Heisenberg and Wolfgang Pauli--had strong interests in the traditional mind--brain, or "hard," problem. This paper reviews their approach to this problem, showing the influence of Bohr's complementarity…

  5. Self-Selected Reading for Enjoyment as a College Developmental Reading Approach

    ERIC Educational Resources Information Center

    Paulson, Eric J.

    2006-01-01

    The field of college developmental reading does not have a unified, agreed-upon approach to creating effective and efficient readers at the college level, as Reynolds and Werner (2003) have pointed out. For example, Keefe and Meyer (1991) assert the appropriateness of a holistic, whole-language approach for adult readers, while Bohr (2003)…

  6. "Paideia," Then and Now.

    ERIC Educational Resources Information Center

    Keppel, Francis

    1990-01-01

    Discusses two widely practiced principles of management (protecting the rear and knowing the limits of a job) as they relate to the philosophy of education. The article examines Werner Jaeger's definition of education in his 1939 book, "Paideia," as well as other definitions that have helped shape current educational management. (SM)

  7. The Information Society in Europe: Work and Life in an Age of Globalization. Critical Media Studies: Institutions, Politics, and Culture.

    ERIC Educational Resources Information Center

    Ducatel, Ken, Ed.; Webster, Juliet, Ed.; Herrmann, Werner, Ed.

    This book takes stock of the existing socioeconomic knowledge about a range of the core social issues of the information society. Chapter 1, "Information Infrastructures or Societies?" (Ken Ducatel, Juliet Webster, Werner Herrmann), is an introduction. Part 1, "Space, Economy, and the Global Information Society" looks at the processes of economic…

  8. Good scientists and honest people

    NASA Astrophysics Data System (ADS)

    Robinson, Andrew

    2014-06-01

    In early 1948, less than three years after the end of the Second World War in Europe, Werner Heisenberg - the Nobel laureate and physicist leader of the failed German atomic bomb project - was invited to the UK as part of an attempt to repair relations between British and German physicists.

  9. New Light on Copenhagen and the German Nuclear Project

    NASA Astrophysics Data System (ADS)

    Cassidy, David C.

    The recent release of draft letters from Niels Bohr to Werner Heisenberg provides new insights into German fission research during World War II and into the reasons for its relative failure. I refute claims of deliberate failure and briefly summarize other contributing factors.

  10. Unification of Fundamental Forces

    NASA Astrophysics Data System (ADS)

    Salam, Abdus; Taylor, Foreword by John C.

    2005-10-01

    Foreword John C. Taylor; 1. Unification of fundamental forces Abdus Salam; 2. History unfolding: an introduction to the two 1968 lectures by W. Heisenberg and P. A. M. Dirac Abdus Salam; 3. Theory, criticism, and a philosophy Werner Heisenberg; 4. Methods in theoretical physics Paul Adrian Maurice Dirac.

  11. The physics of Copenhagen for students and the general public

    NASA Astrophysics Data System (ADS)

    Bergström, L.; Johansson, K. E.; Nilsson, Ch

    2001-09-01

    The play Copenhagen has attracted the attention of a large audience in several countries. The hypothetical discussion in Copenhagen between two of the giants in physics, Niels Bohr and Werner Heisenberg, has inspired us to start a theoretical and experimental exploration of quantum physics. This theme has been used in Stockholm Science Laboratory for audiences of both students and the general public.

  12. q-Deformed Minkowski Algebra and Its Space-Time Lattice

    NASA Astrophysics Data System (ADS)

    Wess, J.

    2Max-Planck-Institut für Physik (Werner-Heisenberg-Institut) Föhringer Ring 6, D-80805 MünchenAbstract. We have asked how the Heisenberg relations of space and time change if we replace the Lorentz group by a q-deformed Lorentz group (Lorek et al. 1997).

  13. Heisenberg and the critical mass

    NASA Astrophysics Data System (ADS)

    Bernstein, Jeremy

    2002-09-01

    An elementary treatment of the critical mass used in nuclear weapons is presented and applied to an analysis of the wartime activities of the German nuclear program. In particular, the work of Werner Heisenberg based on both wartime and postwar documents is discussed.

  14. Cul-de-Sac Kids

    ERIC Educational Resources Information Center

    Hochschild, Thomas R., Jr.

    2013-01-01

    Previous research indicates that adults who live on cul-de-sac streets are more likely to have positive experiences with neighbors than residents of other street types (Brown and Werner, 1985; Hochschild Jr, 2011; Mayo Jr, 1979; Willmott, 1963). The present research ascertains whether street design has an impact on children's neighborhood…

  15. Business Education and Training: A Value-Laden Process. Volume II: The Developing Professional: Maintaining Values in "Practical" Training.

    ERIC Educational Resources Information Center

    Natale, Samuel M., Ed.; Fenton, Mark B., Ed.

    This volume contains 19 papers that explore value conflicts in all professions: "Changing Student Teacher Values with Respect to Business and Industry" (Ralph P. Williams, Elizabeth J. Foster); "Admissions Processes into Canadian Master of Social Work Programs in the 1990s" (John R. Graham, Beatrice Traub-Werner); "Organizational Paradigms and…

  16. Risk, Resilience, and Recovery

    ERIC Educational Resources Information Center

    Werner, Emmy

    2012-01-01

    In 1955, the first longitudinal study of resilience began on the island of Kauai. This research continues to the present. This article presents an interview with Emmy Werner, the principal investigator. In a series of five books published over a period of thirty years, she demonstrated the remarkable ability of children from difficult backgrounds…

  17. The Role of Idiomorphs in Emergent Literacy

    ERIC Educational Resources Information Center

    Neumann, Michelle M.; Neumann, David L.

    2012-01-01

    Psycholinguistics coined the term idiomorph to describe idiosyncratic invented word-like units that toddlers use to refer to familiar objects during their early language development (Haslett & Samter, 1997; Otto, 2008; Reich, 1986; Scovel, 2004; Werner & Kaplan, 1963). Idiomorphs act as "words" because their meanings and phonetic pronunciations…

  18. WHK Interns Win Big at Frederick County Science Fair | Poster

    Cancer.gov

    Three Werner H. Kirsten student interns claimed awards at the 35th Annual Frederick County Science and Engineering Fair—and got a shot at the national competition—for imaginative projects that reached out to the rings of Saturn and down to the details of advanced cancer diagnostics.

  19. Studies in Southwestern Ethnolinguistics; Meaning and History in the Languages of the American Southwest.

    ERIC Educational Resources Information Center

    Hymes, Dell H., Ed.; Bittle, William E., Ed.

    The present festschrift honoring Harry Hoijer is prefaced by the editor, Dell Hymes, and introduced by Stanley Newman. Papers are grouped according to the following content areas and authors: (1) "Meaning in Cultural Forms": D.F. Aberle, F. Eggan, R.A. Black, and D.L. Olmsted; (2) "Meaning in Lexical Systems": S. Ervin-Tripp, H. Landar, O. Werner,…

  20. Consortial Leadership: Cooperation in a Competitive Environment. Proceedings of the Meeting of the Association of Research Libraries (130th, Albuquerque, NM, May 14-16, 1997).

    ERIC Educational Resources Information Center

    Barrett, Jaia, Ed.; Wetzel, Karen A., Ed.

    The program of the 130th meeting of the Association of Research Libraries (ARL) explored the leadership challenges posed by the juxtapositions of cooperation and competing priorities in a consortial environment. Following an opening and welcome (Gloria Werner, ARL Presiding President), and a Keynote Address, "Defining Successful Leadership" (David…

  1. The Narrative Worlds of "What Is" and "What if"

    ERIC Educational Resources Information Center

    Engel, Susan

    2005-01-01

    This paper advances the hypothesis that young children use narrative play and stories to construct two types of fiction, the worlds of "what is" and "what if." Heinz Werner's conceptualization of children's spheres of reality, in which actions, symbols, and events are constructed in particular ways, is used as a theoretical framework for…

  2. Twin-Screw Extruders in Ceramic Extrusion

    NASA Astrophysics Data System (ADS)

    Wiedmann, Werner; Hölzel, Maria

    The machines mainly used for compounding plastics, chemicals and food are co-rotating, closely intermeshing twin-screw extruders. Some 30 000 such extruders are in use worldwide, about 1/3 are ZSKs from Coperion Werner & Pfleiderer, Stuttgart. In the chemical industry more and more batch mixers are being replaced by continuous twin-screw kneaders.

  3. Physical Education and Language Arts: An Interdisciplinary Teaching Approach

    ERIC Educational Resources Information Center

    Solomon, John; Murata, Nathan M.

    2008-01-01

    Physical education is a prime content area for interdisciplinary learning. The movement components of physical education can be used as a medium through which children are provided with opportunities to practice and strengthen language skills. Cone, Werner, Cone, and Woods (1998, p. 4) agree: "interdisciplinary learning is an educational process…

  4. Visualization and Rule Validation in Human-Behavior Representation

    ERIC Educational Resources Information Center

    Moya, Lisa Jean; McKenzie, Frederic D.; Nguyen, Quynh-Anh H.

    2008-01-01

    Human behavior representation (HBR) models simulate human behaviors and responses. The Joint Crowd Federate [TM] cognitive model developed by the Virginia Modeling, Analysis, and Simulation Center (VMASC) and licensed by WernerAnderson, Inc., models the cognitive behavior of crowds to provide credible crowd behavior in support of military…

  5. The Social Relevance of Montessori in the First Plane

    ERIC Educational Resources Information Center

    Andrews, Sarah Werner

    2015-01-01

    This article represents an amazing reversal of linguistic analysis. Usually Montessori language is translated into "state" terminology. In this case, Sarah Werner Andrews puts state quality assessment terms into Montessori language. For example, domains for school readiness include 1) physical wellbeing and motor development, 2) social…

  6. Making a Difference: Innovations in Adult Education.

    ERIC Educational Resources Information Center

    Mauch, Werner, Ed.; Papen, Uta, Ed.

    This book highlights examples of innovative educational practices in the field of organized adult learning. Fifteen chapters present outcomes of collective research in the Innovations in Nonformal and Adult Education (INNAE) project. "Common Learning--Collective Research: Innovating Adult Education" (Werner Mauch, Uta Papen) describes the…

  7. Education and Canadian Multiculturalism: Some Problems and Some Solutions. Eighth Yearbook 1981 = Education et Multiculturalisme Canadien: Quelques Problemes et Solutions. Huitieme Annuaire 1981.

    ERIC Educational Resources Information Center

    Dorotich, Daniel, Ed.

    This yearbook presents a series of articles on Canadian multicultural issues. In the first article, "Panem et Circenses? Ten Years of Multicultural Policy in Canada," Werner Stephan examines criticisms of Canadian multicultural policy and suggests the country has not found a satisfactory answer to what multiculturalism is or should be, or how to…

  8. Havens of Resilience

    ERIC Educational Resources Information Center

    Henderson, Nan

    2013-01-01

    Schools are natural environments for helping all children cultivate the resilience that resides within them. Research shows that schools are filled with the conditions that promote resilience (Werner, 2003). These include caring, encouraging relationships, role models, and mentors (Theron & Engelbrecht, 2012; Thomsen, 2002; Walsh, 2012); clear…

  9. The Development of Symbolic Representation: The Case of Building Blocks.

    ERIC Educational Resources Information Center

    Reifel, Stuart

    The symbolic representational block constructions of twenty 4-year-olds and twenty 7-year-olds were analyzed from Werner and Kaplan's (1963) theoretical perspective. Each child was read a story and then asked to use the blocks to represent the story. Older children included in their representations a larger number of features that were central to…

  10. The Strategic Use of Language: A Sociolinguistic View of Communication Development.

    ERIC Educational Resources Information Center

    Nicholson, James L., III

    This study examined acquisition and development of children's social/symbolic and strategic communication abilities within a sociolinguistic model of communicative competence. The major theoretical perspective was derived from Mead's symbolic interactionism and the cognitive-developmental theories of Piaget and Werner. Role-taking was the central…

  11. Multipartite invariant states. I. Unitary symmetry

    SciTech Connect

    Chruscinski, Dariusz; Kossakowski, Andrzej

    2006-06-15

    We propose a natural generalization of bipartite Werner and isotropic states to multipartite systems consisting of an arbitrary even number of d-dimensional subsystems (qudits). These generalized states are invariant under the action of local unitary operations. We study basic properties of multipartite invariant states and present necessary and sufficient separability criteria.

  12. A Developmental Framework for Enhancing Resiliency in Adult Survivors of Childhood Abuse

    ERIC Educational Resources Information Center

    Orbke, Samantha; Smith, Heather L.

    2013-01-01

    Roughly one third of children subjected to abusive environments grow into healthy and capable adults, demonstrating remarkable resiliency, despite risks for developing maladaptive self-structures and destructive behaviors (Werner, "American Journal of Orthopsychiatry" 59:72-81 1989; Kendall-Tackett "et al.", "Psychological Bulletin" 113:164-180…

  13. Ideas from Ten North American Curriculum Thinkers.

    ERIC Educational Resources Information Center

    Short, Edmund C.

    The views and attitudes of ten North American educational policy-makers concerning curriculum development and design are presented. The theories and research of Herbert M. Kliebard, Fenwick W. English, Walter Werner, John I. Goodlad, Decker F. Walker, William A. Reid, Norman E. Gleadow, Neil Postman, Elliot W. Eisner, and Michael W. Apple are…

  14. Track Analysis of the North, Central, and South American Species of the Epicauta maculata Group (Coleoptera: Meloidae).

    PubMed

    Campos-Soldini, M P; García, M S; Safenraiter, M E

    2015-08-01

    We undertook a panbiogeographic analysis of 23 species of the Epicauta maculata group of America-Epicauta abeona Pinto, Epicauta adspersa (Klug), Epicauta andersoni Werner, Epicauta atomaria (Germar), Epicauta apache Pinto, Epicauta cavernosa (Courbon), Epicauta dilatipennis Pic, Epicauta fulvicornis (Burmeister), Epicauta horni Champion, Epicauta jeffersi Pinto, Epicauta koheleri Denier, Epicauta lizeri Denier, E. maculata (Say), Epicauta magnomaculata Martin, Epicauta minutepunctata Borchmann, Epicauta nigropunctata (Blanchard), Epicauta normalis Werner, Epicauta ocellata (Dugès), Epicauta pardalis LeConte, picauta phoenix Werner, Epicauta pluvialis Borchmann, Epicauta proscripta Werner, Epicauta rubella Denier, and Epicauta ventralis Werner-with the purpose of analyzing the distributional data for taxa, to establish patterns of distribution of an ancestral biota and areas where these groups have interacted. Based on the overlap of 20 individual tracks, four generalized tracks constituted by different numbers of species were identified; two of them are located in the Nearctic region and the Mexican transition zone (tracks "A" and "B"), and the other two are distributed in the Neotropical region and the South America transition zone ("C", "D"). Six nodes were recognized: Two of them are included in the Nearctic Region, node 'I' located in northern USA and node 'II' located in southwestern USA, both at the intersection of the tracks "A" and "B". The other four are included in the Neotropical Region at the intersection of the tracks "C" and "D": Node 'III' is located in Chaco province; node 'IV' is located in Parana Forest province; node 'V' is located in the northwest of Argentina in Puna province, and node 'VI' is located in Monte province. PMID:26174956

  15. Track Analysis of the North, Central, and South American Species of the Epicauta maculata Group (Coleoptera: Meloidae).

    PubMed

    Campos-Soldini, M P; García, M S; Safenraiter, M E

    2015-08-01

    We undertook a panbiogeographic analysis of 23 species of the Epicauta maculata group of America-Epicauta abeona Pinto, Epicauta adspersa (Klug), Epicauta andersoni Werner, Epicauta atomaria (Germar), Epicauta apache Pinto, Epicauta cavernosa (Courbon), Epicauta dilatipennis Pic, Epicauta fulvicornis (Burmeister), Epicauta horni Champion, Epicauta jeffersi Pinto, Epicauta koheleri Denier, Epicauta lizeri Denier, E. maculata (Say), Epicauta magnomaculata Martin, Epicauta minutepunctata Borchmann, Epicauta nigropunctata (Blanchard), Epicauta normalis Werner, Epicauta ocellata (Dugès), Epicauta pardalis LeConte, picauta phoenix Werner, Epicauta pluvialis Borchmann, Epicauta proscripta Werner, Epicauta rubella Denier, and Epicauta ventralis Werner-with the purpose of analyzing the distributional data for taxa, to establish patterns of distribution of an ancestral biota and areas where these groups have interacted. Based on the overlap of 20 individual tracks, four generalized tracks constituted by different numbers of species were identified; two of them are located in the Nearctic region and the Mexican transition zone (tracks "A" and "B"), and the other two are distributed in the Neotropical region and the South America transition zone ("C", "D"). Six nodes were recognized: Two of them are included in the Nearctic Region, node 'I' located in northern USA and node 'II' located in southwestern USA, both at the intersection of the tracks "A" and "B". The other four are included in the Neotropical Region at the intersection of the tracks "C" and "D": Node 'III' is located in Chaco province; node 'IV' is located in Parana Forest province; node 'V' is located in the northwest of Argentina in Puna province, and node 'VI' is located in Monte province.

  16. Renewable Energy Cost Modeling. A Toolkit for Establishing Cost-Based Incentives in the United States

    SciTech Connect

    Gifford, Jason S.; Grace, Robert C.; Rickerson, Wilson H.

    2011-05-01

    This report serves as a resource for policymakers who wish to learn more about levelized cost of energy (LCOE) calculations, including cost-based incentives. The report identifies key renewable energy cost modeling options, highlights the policy implications of choosing one approach over the other, and presents recommendations on the optimal characteristics of a model to calculate rates for cost-based incentives, FITs, or similar policies. These recommendations shaped the design of NREL's Cost of Renewable Energy Spreadsheet Tool (CREST), which is used by state policymakers, regulators, utilities, developers, and other stakeholders to assist with analyses of policy and renewable energy incentive payment structures. Authored by Jason S. Gifford and Robert C. Grace of Sustainable Energy Advantage LLC and Wilson H. Rickerson of Meister Consultants Group, Inc.

  17. Maximum-power quantum-mechanical Carnot engine.

    PubMed

    Abe, Sumiyoshi

    2011-04-01

    In their work [J. Phys. A 33, 4427 (2000)], Bender, Brody, and Meister have shown by employing a two-state model of a particle confined in the one-dimensional infinite potential well that it is possible to construct a quantum-mechanical analog of the Carnot engine through changes of both the width of the well and the quantum state in a specific manner. Here, a discussion is developed about realizing the maximum power of such an engine, where the width of the well moves at low but finite speed. The efficiency of the engine at the maximum power output is found to be universal independently of any of the parameters contained in the model.

  18. [Treatment of rabies in man in Vaud and Fribourg before Pateu: therapeutic observations of Drs. Guisan and Schaller in the 19th century].

    PubMed

    Bosson, A

    2001-01-01

    The picture showing the little Joseph Meister being treated against rabies under Louis Pasteur's eyes, on July 6, 1885, has quickly become a symbol of the triumphant progress of medicine, even though diseases with high mortality like tuberculosis or diphtheria could still not be healed with efficient therapeutic means. But before the discoveries of Pasteur, what was actually, in daily practice, the kind of response an ordinary doctor could give to human rabies? A Swiss physician, Charles-Hector Guisan, developed a therapy based on the use of sodium arsenate, which he published in the columns of the Gazette des Hôpitaux civils et militaires in 1854. This arsenic therapy was to be put into practice on a larger scale in the canton of Fribourg by Dr Jean-Louis Schaller (1816-1880), who meticulously wrote observations in a notebook on the cases of 13 persons wounded by a rabid dog in 1855. PMID:11810985

  19. Bounds and Estimates for Elastic Constants of Random Polycrystals of Laminates

    SciTech Connect

    Berryman, J G

    2004-08-25

    In order to obtain formulas providing estimates for elastic constants of random polycrystals of laminates, some known rigorous bounds of Peselnick, Meister, and Watt are first simplified. Then, some new self-consistent estimates are formulated based on the resulting analytical structure of these bounds. A numerical study is made, assuming first that the internal structure (i.e., the laminated grain structure) is not known, and then that it is known. The purpose of this aspect of the study is to attempt to quantify the differences in the predictions of properties of the same system being modeled when such internal structure of the composite medium and spatial correlation information is and is not available.

  20. Experiment on the concrete slab for floor vibration evaluation of deteriorated building

    NASA Astrophysics Data System (ADS)

    Hong, S. U.; Na, J. H.; Kim, S. H.; Lee, Y. T.

    2014-08-01

    Damages from noise and vibration are increasing every year, and most of which are noises between floors in deteriorated building caused by floor impact sound. In this study, the floor vibration of the deteriorated buildings constructed with the concrete slabs of thickness no more than 150 mm was evaluated by the vibration impact sound. This highly reliable study was conducted to assess floor vibration according with the serviceability evaluation standard of Reiher / Meister and Koch and vibration evaluation standard of ISO and AIJ. Designed pressure for the concrete slab sample of floor vibration assessment was 24MPa, and the sample was manufactured pursuant to KS F 2865 and JIS A 1440-2 with size of 3200 mm × 3200 mm × 140 mm. Tests were conducted twice with accelerometers, and Fast Fourier Transform was performed for comparative analysis by the vibration assessment criteria. The peak displacement from Test 1 was in the range of 0.00869 - 0.02540 mm; the value of peak frequency ranged from 18 to 27 Hz, and the average value was 22Hz. The peak acceleration value from Test 2 was in the range of 0.47 - 1.07 % g; the value of peak frequency was 18.5 - 22.57 Hz, and the average was 21Hz. The vibration was apparently recognizable in most cases according to the Reiher/Meister standard. In case of Koch graph for the damage assessment of the structure, the vibration was at the medium level and causes no damage to the building structure. The measured vibration results did not exceed the damage limit or serviceability limit of building according to the vibration assessment criteria of ISO and residential assessment guidelines provided by Architectural Institute of Japan (AIJ).

  1. Authigenic Carbonate Formation on the Peru Margin; New Insights from IODP Site 1230

    NASA Astrophysics Data System (ADS)

    Abdullajintakam, S.; Naehr, T. H.

    2015-12-01

    Fluid seepage of reduced organic compounds such as methane impacts the geology and biology of the seabed by inducing complex, microbially mediated biogeochemical processes. Authigenic carbonates serve as one of the few permanent records of these of dynamic biogeochemical interactions that involve methanogenesis, methanotrophy, sulfate reduction and carbonate precipitation. Meister et al. (2007) investigated deep-sea dolomite formation at Sites 1227-1229 on the Peru margin, where dolomite precipitation occurs in association with organic carbon-rich continental margin sediments. Geochemical and petrographic studies indicated episodic dolomite precipitation at a dynamic sulfate methane transition zone (SMTZ). Variations in δ13C values of these dolomites between +15‰ and -15‰ were attributed to non-steady state conditions as a result of the upward and downward migration of the SMTZ. Our study aims to better understand the biogeochemical processes associated with authigenic carbonate precipitation in this dynamic deep-sea setting. We focused our efforts on IODP Site 1230, which is a gas-hydrate-bearing site that shows sulphate consumption within the uppermost 10 m below the seafloor as well as high methane production. Using a multi proxy approach, we combined X-ray diffraction, stable isotope geochemistry, and trace metal analysis of authigenic carbonates to elucidate conditions for authigenic carbonate formation. Results from Site 1230 are compared to Sites 1227 and 1229, which lacks gas hydrates and is characterized by high pore water sulfate and low methane concentrations. This study contributes to a more comprehensive understanding of authigenic carbonate formation and associated biogeochemical processes in continental margin sediments. Meister, P., Mckenzie, J. A., Vasconcelos, C., Bernasconi, S., Frank, M., Gutjhar, M. and SCHRAG, D. P. (2007), Dolomite formation in the dynamic deep biosphere: results from the Peru Margin. Sedimentology, 54: 1007-1032.

  2. Heat Storage Characteristics of Latent-Heat Microcapsule Slurry Using Hot Air Bubbles by Direct-Contact Heat Exchange

    NASA Astrophysics Data System (ADS)

    Inaba, Hideo; Horibe, Akihiko; Kim, Myoung-Jun; Tsukamoto, Hirofumi

    This study deals with the heat storage characteristics of latent-heat microcapsule slurry consisting of a mixture of fine microcapsules packed with latent-heat storage material and water. The heat storage operation for the latent-heat microcapsules was carried out by the direct-contact heat exchange method using hot air bubbles. The latent-heat microcapsule consisted of n-paraffin as a core latent-heat storage material and melamine resin as a coating substance. The relationship between the completion time of latent-heat storage and some parameters was examined experimentally. The nondimensional correlation equations for temperature efficiency, the completion time period of the latent-heat storage process and variation in the enthalpy of air through the microcapsule slurry layer were derived in terms of the ratio of microcapsule slurry layer height to microcapsule diameter, Reynolds number for airflow, Stefan number and modified Stefan number for absolute humidity of flowing air.

  3. ITER Plasma at Electron Cyclotron Frequency Domain: Tokamak Core Plasma Diagnostics Based on the Synergy of Stimulated Raman and Brillouin Scatterings

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2012-10-01

    A novel plasma diagnostic method is proposed based on the synergy of stimulated Raman and Brillouin scatterings. A nonlinear plasma mode is excited in a 4-wave coupling,footnotetextV. Alexander STEFAN, Nonlinear Electromagnetic Radiation Plasma Interactions, (S-U-Press, 2008). leading to the appearance of suprathermal electrons and accelerated ions at the plasma edgefootnotetextV. Alexander Stefan, Abstract: D1.00018 : ITER Plasma at Electron Cyclotron Frequency Domain: Stimulated Raman Scattering off Gould-Trivelpiece Modes and Generation of Suprathermal Electrons and Energetic Ions; Bulletin of the American Physical Society APS April Meeting 2011 Volume 56, Number 4. with the parameters directly dependent on the plasma parameters in the core of tokamak. Accordingly, plasma diagnostic in the core region, (ion temperature), can be performed by the diagnostics of suprathermal electrons and accelerated ions at the edge plasma.

  4. Moving boundary problems for the Harry Dym equation and its reciprocal associates

    NASA Astrophysics Data System (ADS)

    Rogers, Colin

    2015-12-01

    Moving boundary problems of generalised Stefan type are considered for the Harry Dym equation via a Painlevé II symmetry reduction. Exact solutions of such nonlinear boundary value problems are obtained in terms of Yablonski-Vorob'ev polynomials corresponding to an infinite sequence of values of the Painlevé II parameter. The action of two kinds of reciprocal transformation on the moving boundary problems is described.

  5. Thermochromic Infrared Metamaterials.

    PubMed

    Liu, Xinyu; Padilla, Willie J

    2016-02-01

    An infrared artificial thermochromic material composed of a metamaterial emitter and a bimaterial micro-electro-mechanical system is investigated. A differential emissivity of over 30% is achieved between 623 K and room temperature. The passive metamaterial device demonstrates the ability to independently control the peak wavelength and temperature dependence of the emissivity, and achieves thermal emission following a super Stefan-Boltzmann power curve. PMID:26619382

  6. SCALE ANALYSIS OF CONVECTIVE MELTING WITH INTERNAL HEAT GENERATION

    SciTech Connect

    John Crepeau

    2011-03-01

    Using a scale analysis approach, we model phase change (melting) for pure materials which generate internal heat for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. We show the time scales in which conduction and convection heat transfer dominate.

  7. Heat transfer in damaged material

    NASA Astrophysics Data System (ADS)

    Kruis, J.

    2013-10-01

    Fully coupled thermo-mechanical analysis of civil engineering problems is studied. The mechanical analysis is based on damage mechanics which is useful for modeling of behaviour of quasi-brittle materials, especially in tension. The damage is assumed to be isotropic. The heat transfer is assumed in the form of heat conduction governed by the Fourier law and heat radiation governed by the Stefan-Boltzmann law. Fully coupled thermo-mechanical problem is formulated.

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  9. Thermochromic Infrared Metamaterials.

    PubMed

    Liu, Xinyu; Padilla, Willie J

    2016-02-01

    An infrared artificial thermochromic material composed of a metamaterial emitter and a bimaterial micro-electro-mechanical system is investigated. A differential emissivity of over 30% is achieved between 623 K and room temperature. The passive metamaterial device demonstrates the ability to independently control the peak wavelength and temperature dependence of the emissivity, and achieves thermal emission following a super Stefan-Boltzmann power curve.

  10. A direct method for calculating thermodynamic factors for liquid mixtures using the Permuted Widom test particle insertion method

    NASA Astrophysics Data System (ADS)

    Prasaad Balaji, Sayee; Schnell, Sondre K.; McGarrity, Erin S.; Vlugt, Thijs J. H.

    2013-01-01

    Understanding mass transport in liquids by mutual diffusion is an important topic for many applications in chemical engineering. The reason for this is that diffusion is often the rate limiting step in chemical reactors and separators. In multicomponent liquid mixtures, transport diffusion can be described by both generalized Fick's law and the Maxwell-Stefan theory. The Maxwell-Stefan and Fick approaches in an n-component system are related by the so-called thermodynamic factor [R. Taylor and H.A. Kooijman, Chem. Eng. Commun, 102, 87 (1991)]. As Fick diffusivities can be measured in experiments and Maxwell-Stefan diffusivities can be obtained from molecular simulations/theory, the thermodynamic factors bridge the gap between experiments and molecular simulations/theory. It is therefore desirable to be able to compute thermodynamic factors from molecular simulations. Unfortunately, presently used simulation techniques for computing thermodynamic factors are inefficient and often require numerical differentiation of simulation results. In this work, we propose a modified version of the Widom test-particle method to compute thermodynamic factors from a single simulation. This method is found to be more efficient than the conventional Widom test particle insertion method combined with numerical differentiation of simulation results. The approach is tested for binary systems consisting of Lennard-Jones particles. The thermodynamic factors computed from the simulation and from numerically differentiating the activity coefficients obtained from the conventional Widom test particle insertion method are in excellent agreement.

  11. Deconfinement of Quarks with TeV Attosecond Photon Beams

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2010-02-01

    Recently, I have proposed a novel heuristic method for the deconfinement of quarks.footnotetextM. Gell-Mann. The Quark and the Jaguar: Adventures in the Simple and the Complex (New York, NY: W.H. Freeman and Co., 1994) [cf. M. Gell-Mann, The Garden of Live Flowers in: V. Stefan (Editor), Physics and Society. Essays Honoring Victor Frederick Weisskopf (Springer, 1998), pp. 109-121]. It proceeds in two phases.footnotetextV. Alexander Stefan, On a Heuristic Point of View About Inertial Deconfinement of Quarks, American Physical Society, 2009 APS April Meeting, May 2-5, 2009, abstract #E1.038. Firstly, a frozen hydrogen pellet is inertially confined by the ultra-intense lasers up to a solid state density. Secondly, a solid state nano-pellet is ``punched'' by the photon beam created in the beat wave driven free electron laser (BW-FEL), leading to the ``rapture'' (in a ``karate chop'' model) of the ``MIT Bag''footnotetextJ. I. Friedman and H. Kendall, Viki, in: V. Stefan (Editor), Physics and Society. (Springer, 1998), pp. 103-108]. before the asymptotically free quarks move apart. Hereby, I propose TeV, a few 100s attosecond, photon beams in interaction with the nano-pellet. The threshold ``rapture force'' of the TeV attosecond photon is 10^7 N. )

  12. Laser-Neuron Interaction with Femtosecond Beat-Modulated 800-1200 nm Photon Beams, as the Treatment of Brain Cancer Tissue. Laser Neurophysics

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2011-03-01

    I propose a novel mechanism for the brain cancer tissue treatment: nonlinear interaction of ultrashort pulses of beat-photon, (ω1 -- ω2) , or double-photon, (ω1 +ω2) , beams with the cancer tissue. The multiphoton scattering is described via photon diffusion equation. The open-scull cerebral tissue can be irradiated with the beat-modulated photon pulses with the laser irradiances in the range of a few mW/cm2 , and repetition rate of a few 100s Hz generated in the beat-wave driven free electron laser. V. Stefan, B. I. Cohen, and C. Joshi, Nonlinear Mixing of Electromagnetic Waves in PlasmasScience 27 January 1989: V. Alexander Stefan, Genomic Medical Physics: A New Physics in the Making, (S-U-Press, 2008).} This highly accurate cancer tissue ablation removal may prove to be an efficient method for the treatment of brain cancer. Work supported in part by Nikola Tesla Laboratories (Stefan University), La Jolla, CA.

  13. Intervention with disadvantaged parents of sick preterm infants.

    PubMed

    Beckwith, L

    1988-08-01

    Infants born preterm are, as a group, at increased risk for a wide variety of later developmental problems (Kopp and Parmelee 1979), although many preterm infants do well (Hack et al. 1983; Saigal et al. 1984). The perinatal vulnerability, however, is amplified in disadvantaged families (Sameroff and Chandler 1975), increasing the likelihood of later emotional and cognitive difficulties (Werner and Smith 1977). A preventive intervention project was designed, therefore, that would provide and then evaluate the effectiveness of supportive home visitor services to parents of infants who were at double jeopardy, both biologically and socially--that is, sick preterm infants being reared by low-income parents. E. Baxter, K. Weiler and I hypothesized that if intervention could increase mothers' involvement and level of responsive interactions with their children, that increased maternal commitment and responsiveness to the infant would act as a protective factor ameliorating or preventing later problems in the child (Beckwith and Cohen 1984; Werner and Smith 1982).

  14. Line Overlap and Self-Shielding of Molecular Hydrogen in Galaxies

    NASA Astrophysics Data System (ADS)

    Gnedin, Nickolay Y.; Draine, Bruce T.

    2014-11-01

    The effect of line overlap in the Lyman and Werner bands, often ignored in galactic studies of the atomic-to-molecular transition, greatly enhances molecular hydrogen self-shielding in low metallicity environments and dominates over dust shielding for metallicities below about 10% solar. We implement that effect in cosmological hydrodynamics simulations with an empirical model, calibrated against the observational data, and provide fitting formulae for the molecular hydrogen fraction as a function of gas density on various spatial scales and in environments with varied dust abundance and interstellar radiation field. We find that line overlap, while important for detailed radiative transfer in the Lyman and Werner bands, has only a minor effect on star formation on galactic scales, which, to a much larger degree, is regulated by stellar feedback.

  15. Writing My Way to My Future | Poster

    Cancer.gov

    By Nathalie Walker, Guest Writer Editor’s note: This article is the second in a series describing one student’s perspective on her experiences as a Werner H. Kirsten student intern. “The future depends on what you do today.” Those wise words were spoken by Mahatma Gandhi. Before I started my Werner H. Kirsten (WHK) student internship, I did not know what I know now. I only knew what each of Gandhi’s words meant individually. I now understand the full meaning of the phrase. To me, Gandhi’s words mean that nothing in life is handed to you. You have to work hard today to get the results you want tomorrow.

  16. Dynamics of bell-nonlocality for two atoms interacting with a vacuum multi-mode noise field

    NASA Astrophysics Data System (ADS)

    Liu, Yu-Jie; Zheng, Li; Han, Dong-Mei; Lü, Huan-Lin; Zheng, Tai-Yu

    2016-06-01

    We investigate the internal-state Bell nonlocal entanglement dynamics, as measured by CHSH inequality of two atoms interacting with a vacuum multi-mode noise field by taking into account the spatial degrees of freedom of the two atoms. The dynamics of Bell nonlocality of the atoms with the atomic internal states being initially in a Werner-type state is studied, by deriving the analytical solutions of the Schrödinger equation, and tracing over the degrees of freedom of the field and the external motion of the two atoms. In addition, through comparison with entanglement as measured by concurrence, we find that the survival time of entanglement is much longer than that of the Bell-inequality violation. And the comparison of the quantum correlation time between two Werner-type states is discussed.

  17. Rovibrational States of ClHCl- Isotopomers: a Joint Theoretical and Spectroscopic Investigation

    NASA Astrophysics Data System (ADS)

    Botschwina, P.; Sebald, P.; Oswald, R.; Kawaguchi, K.

    2012-06-01

    Explicitly correlated coupled cluster theory at the CCSD(T*)-F12b level and two precise spectroscopic constants were used to construct an analytical potential energy function (PEF) for highly anharmonic ClHCl-. From variational calculations with that PEF, a large number of rovibrational energies of different isotopomers were obtained. Theory helped with assignments of lines observed by IR diode laser spectroscopy and enabled to elucidate rather complex and unusual patterns of rovibrational interactions. In addition, transition dipole moments were predicted and analyzed. T. B. Adler, G. Knizia, and H.-J. Werner, J. Chem. Phys. 127, 221106 (2007) G. Knizia, T. B. Adler, and H.-J. Werner, J. Chem. Phys. 130, 054104 (2009). K. Kawaguchi, J. Chem. Phys. 88, 4186 (1988).

  18. Line overlap and self-shielding of molecular hydrogen in galaxies

    SciTech Connect

    Gnedin, Nickolay Y.; Draine, Bruce T. E-mail: andrey@oddjob.uchicago.edu

    2014-11-01

    The effect of line overlap in the Lyman and Werner bands, often ignored in galactic studies of the atomic-to-molecular transition, greatly enhances molecular hydrogen self-shielding in low metallicity environments and dominates over dust shielding for metallicities below about 10% solar. We implement that effect in cosmological hydrodynamics simulations with an empirical model, calibrated against the observational data, and provide fitting formulae for the molecular hydrogen fraction as a function of gas density on various spatial scales and in environments with varied dust abundance and interstellar radiation field. We find that line overlap, while important for detailed radiative transfer in the Lyman and Werner bands, has only a minor effect on star formation on galactic scales, which, to a much larger degree, is regulated by stellar feedback.

  19. Revamping the Classroom Research Project

    ERIC Educational Resources Information Center

    Werner-Burke, Nanci

    2014-01-01

    Too often, students don't feel engaged in their research projects. The problem begins as early as the topic-creation stage, when students may choose from a list of teacher-selected topics that don't interest them or struggle to select a single fruitful topic on their own. Nanci Werner-Burke describes how two students in an English…

  20. Student Intern Ben Freed Competes as Finalist in Intel STS Competition, Three Other Interns Named Semifinalists | Poster

    Cancer.gov

    By Ashley DeVine, Staff Writer Werner H. Kirstin (WHK) student intern Ben Freed was one of 40 finalists to compete in the Intel Science Talent Search (STS) in Washington, DC, in March. “It was seven intense days of interacting with amazing judges and incredibly smart and interesting students. We met President Obama, and then the MIT astronomy lab named minor planets after each of us,” Freed said of the competition.  

  1. Spring Research Festival Highlighted on WHAG-TV | Poster

    Cancer.gov

    WHAG-TV (Hagerstown, Md.) visited Fort Detrick to highlight the 2015 Spring Research Festival (SRF), sponsored by the National Interagency Confederation for Biological Research (NICBR). Visit the WHAG-TV website to see the video broadcast, which aired May 6. The video was produced by WHAG Reporter Mallory Sofastaii. The video featured Linganore High School senior Rebecca Matthews, a Werner H. Kirsten student intern in the Human Retrovirus Pathogenesis Section, Vaccine Branch, NCI Center for Cancer Research; Lanessa Hill, public affairs specialist,

  2. The Strange Friendship of Pauli and Jung - When Physics Met Psychology

    SciTech Connect

    2009-12-11

    At a key time in his scientific development, Pauli was undergoing analysis by Jung. What can we learn about Pauli's discoveries of the exclusion principle and the CPT theorem, as well as his thoughts on non-conservation of parity, and his quest with Heisenberg for a unified field theory of elementary particles from Jung’s analysis of his dreams? A very different Pauli emerges, one at odds with esteemed colleagues such as Niels Bohr and Werner Heisenberg.

  3. Heisenberg Probably Slept Here: The Lives, Times, and Ideas of the Great Physicists of the 20th Century

    NASA Astrophysics Data System (ADS)

    Brennan, Richard P.

    1998-09-01

    "Here is a book I wish I had when taking physics my senior year in high school!" -Book Report A lively illumination of modern physics' marquee players, featuring: * Albert Einstein * Max Planck * Ernest Rutherford * Niels Bohr * Werner Heisenberg * Richard Feynman * Murray Gell-Mann "Brennan has a knack for explaining difficult technicalities simply. His essays give a useful summary of twentieth-century science." -Financial Times "Highly recommended to expert and layperson alike." -Choice

  4. Physikgeschichte Das Rätsel bleibt

    NASA Astrophysics Data System (ADS)

    Hoffmann, Dieter

    2002-05-01

    Die jüngst erfolgte Veröffentlichung von Dokumenten aus dem Privatarchiv der Familie Bohr [1] über den geheimnisumwitterten Besuch von Werner Heisenberg in Kopenhagen im September 1941 hat in den deutschen Medien große Resonanz gefunden [2]. Tatsächlich verraten uns die jetzt veröffentlichten Dokumente sehr viel mehr über die Zeit ihres Entstehens als über den Besuch selbst.

  5. Max-Planck-Institut für Astrophysik

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The Max-Planck-Institut für Astrophysik, now located in the town of Garching north of Munich in Germany, is one of the more than 70 autonomous research institutes of the Max-Planck-Gesellschaft. It was founded in 1958 under the direction of Ludwig Biermann as part of the Max-Planck-Institut für Physik und Astrophysik, directed at that time by Werner Heisenberg. In 1979, when the headquarters of t...

  6. The Bohr paradox

    NASA Astrophysics Data System (ADS)

    Crease, Robert P.

    2008-05-01

    In his book Niels Bohr's Times, the physicist Abraham Pais captures a paradox in his subject's legacy by quoting three conflicting assessments. Pais cites Max Born, of the first generation of quantum physics, and Werner Heisenberg, of the second, as saying that Bohr had a greater influence on physics and physicists than any other scientist. Yet Pais also reports a distinguished younger colleague asking with puzzlement and scepticism "What did Bohr really do?".

  7. Entropic Uncertainty Relation and Information Exclusion Relation for multiple measurements in the presence of quantum memory

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Zhang, Yang; Yu, Chang-Shui

    2015-06-01

    The Heisenberg uncertainty principle shows that no one can specify the values of the non-commuting canonically conjugated variables simultaneously. However, the uncertainty relation is usually applied to two incompatible measurements. We present tighter bounds on both entropic uncertainty relation and information exclusion relation for multiple measurements in the presence of quantum memory. As applications, three incompatible measurements on Werner state and Horodecki’s bound entangled state are investigated in details.

  8. Physicists and Physics in Munich

    NASA Astrophysics Data System (ADS)

    Teichmann, Jürgen; Eckert, Michael; Wolff, Stefan

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

  9. Austria in U-turn over CERN pull-out

    NASA Astrophysics Data System (ADS)

    Banks, Michael

    2009-06-01

    Austria will not be withdrawing as a member of the CERN particle-physics laboratory after its chancellor Werner Faymann overruled a decision taken by the country's science minister last month to quit the lab. Researchers in Austria were left shocked when Johannes Hahn unexpectedly announced on 8 May that the country would cut its funding for CERN, worth about €20m per year. Austria - one of the co-founders of CERN - will now remain a full member of the lab.

  10. Alumni of High School Internship Program Return for 25th Anniversary to Inspire Current Students | Poster

    Cancer.gov

    The Building 549 auditorium is often packed with high school interns eager to hear a scientific lecture. On April 22, however, the room swelled with interns spanning a wider age range. At the 25th Werner H. Kirsten Student Intern Program (WHK SIP) Anniversary Symposium, incoming, current, and former interns gathered to celebrate the program, which has provided biomedical research experience for local high school seniors.

  11. The Strange Friendship of Pauli and Jung - When Physics Met Psychology

    ScienceCinema

    None

    2016-07-12

    At a key time in his scientific development, Pauli was undergoing analysis by Jung. What can we learn about Pauli's discoveries of the exclusion principle and the CPT theorem, as well as his thoughts on non-conservation of parity, and his quest with Heisenberg for a unified field theory of elementary particles from Jung’s analysis of his dreams? A very different Pauli emerges, one at odds with esteemed colleagues such as Niels Bohr and Werner Heisenberg.

  12. WHK Interns Sweep Entire Category at Frederick County Science Fair | Poster

    Cancer.gov

    By Nancy Parrish, Staff Writer The competitors in the cellular and molecular biology category of the Frederick County Science and Engineering Fair on March 22–23 didn’t stand a chance against the Werner H. Kirsten student interns at the National Cancer Institute at Frederick. These interns swept the entire category, with Madelyne Xiao, a rising intern, winning first place; Maria Hamscher, second place; Ashley Babyak and Dahlia Kronfli tying for third place; and Maham Ahmed receiving an honorable mention.

  13. Entropic Uncertainty Relation and Information Exclusion Relation for multiple measurements in the presence of quantum memory.

    PubMed

    Zhang, Jun; Zhang, Yang; Yu, Chang-shui

    2015-01-01

    The Heisenberg uncertainty principle shows that no one can specify the values of the non-commuting canonically conjugated variables simultaneously. However, the uncertainty relation is usually applied to two incompatible measurements. We present tighter bounds on both entropic uncertainty relation and information exclusion relation for multiple measurements in the presence of quantum memory. As applications, three incompatible measurements on Werner state and Horodecki's bound entangled state are investigated in details. PMID:26118488

  14. Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    A development of quantum theory that was initiated in the 1920s by Werner Heisenberg (1901-76) and Erwin Schrödinger (1887-1961). The theory drew on a proposal made in 1925 Prince Louis de Broglie (1892-1987), that particles have wavelike properties (the wave-particle duality) and that an electron, for example, could in some respects be regarded as a wave with a wavelength that depended on its mo...

  15. Progress in Understanding the Impacts of 3-D Cloud Structure on MODIS Cloud Property Retrievals for Marine Boundary Layer Clouds

    NASA Technical Reports Server (NTRS)

    Zhang, Zhibo; Werner, Frank; Miller, Daniel; Platnick, Steven; Ackerman, Andrew; DiGirolamo, Larry; Meyer, Kerry; Marshak, Alexander; Wind, Galina; Zhao, Guangyu

    2016-01-01

    Theory: A novel framework based on 2-D Tayler expansion for quantifying the uncertainty in MODIS retrievals caused by sub-pixel reflectance inhomogeneity. (Zhang et al. 2016). How cloud vertical structure influences MODIS LWP retrievals. (Miller et al. 2016). Observation: Analysis of failed MODIS cloud property retrievals. (Cho et al. 2015). Cloud property retrievals from 15m resolution ASTER observations. (Werner et al. 2016). Modeling: LES-Satellite observation simulator (Zhang et al. 2012, Miller et al. 2016).

  16. Gravitational lensing by Reissner-Nordström black holes with topological defects

    NASA Astrophysics Data System (ADS)

    Jusufi, Kimet

    2016-01-01

    Using a new geometrical approach introduced by Gibbons and Werner we study the deflection angle by Reissner-Nordström black holes in the background spacetimes with a global monopole and a cosmic string. By calculating the corresponding optical Gaussian curvature and applying the Gauss-Bonnet theorem to the optical metric we find the leading terms of the deflection angle in the weak limit approximation. We find that the deflection angle increases due to the presence of topological defects.

  17. WHK Student Internship Enrollment, Mentor Participation Up More than 50 Percent | Poster

    Cancer.gov

    By Nancy Parrish, Staff Writer The Werner H. Kirsten Student Internship Program (WHK SIP) has enrolled the largest class ever for the 2013–2014 academic year, with 66 students and 50 mentors. This enrollment reflects a 53 percent increase in students and a 56 percent increase in mentors, compared to 2012–2013 (43 students and 32 mentors), according to Julie Hartman, WHK SIP director.

  18. Image Processing Software

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Ames digital image velocimetry technology has been incorporated in a commercially available image processing software package that allows motion measurement of images on a PC alone. The software, manufactured by Werner Frei Associates, is IMAGELAB FFT. IMAGELAB FFT is a general purpose image processing system with a variety of other applications, among them image enhancement of fingerprints and use by banks and law enforcement agencies for analysis of videos run during robberies.

  19. Entropic Uncertainty Relation and Information Exclusion Relation for multiple measurements in the presence of quantum memory.

    PubMed

    Zhang, Jun; Zhang, Yang; Yu, Chang-shui

    2015-06-29

    The Heisenberg uncertainty principle shows that no one can specify the values of the non-commuting canonically conjugated variables simultaneously. However, the uncertainty relation is usually applied to two incompatible measurements. We present tighter bounds on both entropic uncertainty relation and information exclusion relation for multiple measurements in the presence of quantum memory. As applications, three incompatible measurements on Werner state and Horodecki's bound entangled state are investigated in details.

  20. Genome wide expression profiling of angiogenic signaling and the Heisenberg uncertainty principle.

    PubMed

    Huber, Peter E; Hauser, Kai; Abdollahi, Amir

    2004-11-01

    Genome wide DNA expression profiling coupled with antibody array experiments using endostatin to probe the angiogenic signaling network in human endothelial cells were performed. The results reveal constraints on the measuring process that are of a similar kind as those implied by the uncertainty principle of quantum mechanics as described by Werner Heisenberg. We describe this analogy and argue for its heuristic utility in the conceptualization of angiogenesis as an important step in tumor formation.

  1. Regulation of WRN helicase activity in human base excision repair.

    PubMed

    Ahn, Byungchan; Harrigan, Jeanine A; Indig, Fred E; Wilson, David M; Bohr, Vilhelm A

    2004-12-17

    Werner syndrome patients are deficient in the Werner protein (WRN), which is a multifunctional nuclear protein possessing 3'-5' exonuclease and ATP-dependent helicase activities. Studies of Werner syndrome cells and biochemical studies of WRN suggest that WRN plays a role in several DNA metabolic pathways. WRN interacts with DNA polymerase beta (pol beta) and stimulates pol beta strand displacement synthesis on a base excision repair (BER) intermediate in a helicase-dependent manner. In this report, we examined the effect of the major human apurinic/apyrimidinic endonuclease (APE1) and of pol beta on WRN helicase activity. The results show that WRN alone is able to unwind several single strand break BER intermediates. However, APE1 inhibits WRN helicase activity on these intermediates. This inhibition is likely due to the binding of APE1 to nicked apurinic/apyrimidinic sites, suggesting that APE1 prevents the promiscuous unwinding of BER intermediates. This inhibitory effect was relieved by the presence of pol beta. A model involving the pol beta-mediated hand-off of WRN protein is proposed based on these results.

  2. Heisenberg: Paralleling Scientific and Historical Methods

    NASA Astrophysics Data System (ADS)

    Cofield, Calla

    2007-04-01

    Werner Heisenberg is an important historical subject within the physics community partly because his actions as a human being are discussed nearly as often as his work as a physicist. But does the scientific community establish it's historical ideas with the same methods and standards as it's scientific conclusions? I interviewed Heisenberg's son, Jochen Heisenberg, a professor of physics at UNH. Despite a great amount of literature on Werner Heisenberg, only one historian has interviewed Jochen about his father and few have interviewed Werner's wife. Nature is mysterious and unpredictable, but it doesn't lie or distort like humans, and we believe it can give ``honest'' results. But are we keeping the same standards with history that we do with science? Are we holding historians to these standards and if not, is it up to scientists to not only be keepers of scientific understanding, but historical understanding as well? Shouldn't we record history by using the scientific method, by weighing the best sources of data differently than the less reliable, and are we right to be as stubborn about changing our views on history as we are about changing our views on nature?

  3. Accelerated aging syndromes, are they relevant to normal human aging?

    PubMed

    Dreesen, Oliver; Stewart, Colin L

    2011-09-01

    Hutchinson-Gilford Progeria (HGPS) and Werner syndromes are diseases that clinically resemble some aspects of accelerated aging. HGPS is caused by mutations in theLMNA gene resulting in post-translational processing defects that trigger Progeria in children. Werner syndrome, arising from mutations in the WRN helicase gene, causes premature aging in young adults. What are the molecular mechanism(s) underlying these disorders and what aspects of the diseases resemble physiological human aging? Much of what we know stems from the study of patient derived fibroblasts with both mutations resulting in increased DNA damage, primarily at telomeres. However, in vivo patients with Werner's develop arteriosclerosis, among other pathologies. In HGPS patients, including iPS derived cells from HGPS patients, as well as some mouse models for Progeria, vascular smooth muscle (VSM) appears to be among the most severely affected tissues. Defective Lamin processing, associated with DNA damage, is present in VSM from old individuals, indicating processing defects may be a factor in normal aging. Whether persistent DNA damage, particularly at telomeres, is the root cause for these pathologies remains to be established, since not all progeroid Lmna mutations result in DNA damage and genome instability.

  4. Lack of association of the WRN C1367T polymorphism with senile cataract in the Israeli population

    PubMed Central

    Ehrenberg, M.; Dratviman-Storobinsky, O.; Avraham-Lubin, B.R.

    2010-01-01

    Purpose Werner syndrome is an autosomal recessive disease of premature aging caused by a polymorphic C1367T mutation in the Werner (WRN) gene. Although there are differences between the pathobiology of normal aging and the phenotype of Werner syndrome, the clinical age-related changes are similar. The aim of the study was to investigate the incidence of the C1367T (rs1346044) polymorphism in patients with age-related cataract. Methods The study group consisted of 81 patients with senile cataract undergoing cataract extraction surgery. Data on age, sex, and medical history of microvascular disease and cancer were obtained from the medical files. Anterior lens capsule material was collected during surgery. DNA was extracted, amplified by polymerase chain reaction, and screened for the C1367T polymorphism in WRN using restriction enzymes followed by sequencing. Results There were 33 male and 48 female patients of mean age 74.3±9 years. Genotypic frequencies were 67% for TT and 33% for TC. None of the patients had the CC genotype. Ten patients had a history of myocardial infarct, 8 cerebrovascular accident, and 8 various tumors. The distribution of these morbidities was similar in the two genotype groups. Conclusions The distribution of the C1367T WRN polymorphism in patients with senile cataract is similar to that in the normal population. Cataract formation in the elderly is not linked to a WRN mutation. PMID:20808731

  5. Minimum Error Fickian Diffusion Coefficients for Mass Diffusion in Multicomponent Gas Mixtures

    NASA Astrophysics Data System (ADS)

    Subramaniam, S.

    1999-04-01

    Mass diffusion in multicomponent gas mixtures is governed by a coupled system of linear equations for the diffusive mass fluxes in terms of thermodynamic driving forces, known as the generalized Stefan-Maxwell equation. In computations of mass diffusion in multicomponent gas mixtures, this coupling between the different components results in considerable computational overhead. Consequently, simplified diffusion models for the diffusive mass fluxes as explicit functions of the driving forces are an attractive alternative. These models can be interpreted as an approximate solution to the Stefan-Maxwell equation. Simplified diffusion models require the specification of “effective” diffusion coefficients which are usually expressed as functions of the binary diffusion coefficients of each species pair in the mixture. Current models for the effective diffusion coefficients are incapable of providing a priori control over the error incurred in the approximate solution. In this paper a general form for diagonal approximations is derived, which accounts for the requirement imposed by the special structure of the Stefan-Maxwell equation that such approximations be constructed in a reduced-dimensional subspace. In addition, it is shown that current models can be expressed as particular cases of two general forms, but not all these models correspond to the general form for diagonal approximations. A new minimum error diagonal approximation (MEDA) model is proposed, based on the criterion that the diagonal approximation minimize the error in the species velocities. Analytic expressions are derived for the MEDA model's effective diffusion coefficients based on this criterion. These effective diffusion coefficients automatically give the correct solution in two important limiting cases: for that of a binary mixture, and for the case of arbitrary number of components with identical binary diffusivities. Although these minimum error effective diffusion

  6. Modelling Sensor and Target effects on LiDAR Waveforms

    NASA Astrophysics Data System (ADS)

    Rosette, J.; North, P. R.; Rubio, J.; Cook, B. D.; Suárez, J.

    2010-12-01

    The aim of this research is to explore the influence of sensor characteristics and interactions with vegetation and terrain properties on the estimation of vegetation parameters from LiDAR waveforms. This is carried out using waveform simulations produced by the FLIGHT radiative transfer model which is based on Monte Carlo simulation of photon transport (North, 1996; North et al., 2010). The opportunities for vegetation analysis that are offered by LiDAR modelling are also demonstrated by other authors e.g. Sun and Ranson, 2000; Ni-Meister et al., 2001. Simulations from the FLIGHT model were driven using reflectance and transmittance properties collected from the Howland Research Forest, Maine, USA in 2003 together with a tree list for a 200m x 150m area. This was generated using field measurements of location, species and diameter at breast height. Tree height and crown dimensions of individual trees were calculated using relationships established with a competition index determined for this site. Waveforms obtained by the Laser Vegetation Imaging Sensor (LVIS) were used as validation of simulations. This provided a base from which factors such as slope, laser incidence angle and pulse width could be varied. This has enabled the effect of instrument design and laser interactions with different surface characteristics to be tested. As such, waveform simulation is relevant for the development of future satellite LiDAR sensors, such as NASA’s forthcoming DESDynI mission (NASA, 2010), which aim to improve capabilities of vegetation parameter estimation. ACKNOWLEDGMENTS We would like to thank scientists at the Biospheric Sciences Branch of NASA Goddard Space Flight Center, in particular to Jon Ranson and Bryan Blair. This work forms part of research funded by the NASA DESDynI project and the UK Natural Environment Research Council (NE/F021437/1). REFERENCES NASA, 2010, DESDynI: Deformation, Ecosystem Structure and Dynamics of Ice. http

  7. Effect of soil property uncertainties on permafrost thaw projections: A calibration-constrained analysis

    DOE PAGES

    Harp, Dylan R.; Atchley, Adam L.; Painter, Scott L.; Coon, Ethan T.; Wilson, Cathy J.; Romanovsky, Vladimir E.; Rowland, Joel C.

    2016-02-11

    Here, the effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21more » $$^{st}$$ century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties

  8. Effect of soil property uncertainties on permafrost thaw projections: A calibration-constrained analysis

    DOE PAGES

    Harp, D. R.; Atchley, A. L.; Painter, S. L.; Coon, E. T.; Wilson, C. J.; Romanovsky, V. E.; Rowland, J. C.

    2015-06-29

    The effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows formore » the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties, although

  9. Effect of soil property uncertainties on permafrost thaw projections: A calibration-constrained analysis

    SciTech Connect

    Harp, D. R.; Atchley, A. L.; Painter, S. L.; Coon, E. T.; Wilson, C. J.; Romanovsky, V. E.; Rowland, J. C.

    2015-06-29

    The effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties, although significant, is

  10. Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis

    NASA Astrophysics Data System (ADS)

    Harp, D. R.; Atchley, A. L.; Painter, S. L.; Coon, E. T.; Wilson, C. J.; Romanovsky, V. E.; Rowland, J. C.

    2015-06-01

    The effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties, although significant, is

  11. The future of electron microscopy

    SciTech Connect

    Zhu, Yimei; Durr, Hermann

    2015-04-01

    Seeing is believing. So goes the old adage and seen evidence is undoubtedly satisfying because it can be interpreted easily, though not always correctly. For centuries, humans have developed such instruments as telescopes that observe the heavens and microscopes that reveal bacteria and viruses. The 2014 Nobel Prize in Chemistry was awarded to Eric Betzig, Stefan Hell, and William Moerner for their foundational work on superresolution fluorescence microscopy in which they overcame the Abbe diffraction limit for the resolving power of conventional light microscopes. (See Physics Today, December 2014, page 18.) That breakthrough enabled discoveries in biological research and testifies to the importance of modern microscopy.

  12. An overview of results obtained in intercomparison exercises for determination of actinides.

    PubMed

    Benedik, L

    2013-11-01

    In recent years the Jožef Stefan Institute participated in numerous intercomparison exercises for determination of natural and man-made radionuclides. The reported values were mostly in good agreement with the resulting reference values. This paper describes an analysis of the measurement results obtained in intercomparison exercises for determination of actinides in the period from 2009 to 2011, organised by the National Physical Laboratory and the Bundesamt für Strahlenschutz. The review covers neptunium, plutonium and americium radioisotopes over this period.

  13. Binary gaseous diffusion coefficients. 5. Cyclooctane and trans-1,2-dimethylcyclohexane with helium, argon, methane, and sulfur hexafluoride at 1 atm and 313-343 K

    SciTech Connect

    Park, T.; Rettich, T.R.; Battino, R.; Emmerich, W.

    1987-04-01

    The binary gaseous diffusion coefficients for cyclooctane and trans-1,2-dimethylcyclohexane diffusing into helium, argon, methane, and sulfur hexafluoride were measured at about 313.15, 328.15, and 343.15K and atmospheric pressure by the capillary tube method of Stefan. The experimental results are compared with diffusion coefficients calculated via the first-order Chapman-Enskog approximation. For the gases, effective Lennard-Jones pair potential parameters were taken from recent literature; for the liquids they were obtained from an extended corresponding-states correlation.

  14. An Illustrated Overview of the Origins and Development of the QSCP Meetings

    NASA Astrophysics Data System (ADS)

    Maruani, Jean

    The origins and development of the QSCP meetings are recalled: from a congress organized in Paris in 1986 to honour Prof. Raymond Daudel, through Franco-Bulgarian cooperation between various teams then European contracts, in the frame of COST projects, involving a network of French, Spanish, British, Italian, Swedish, and Bulgarian scientists, till the holding of the first QSCP workshop near Pisa in 1996 to honour Prof. Stefan Christov. After that there was a meeting every year, always with proceedings published. This historical overview will be presented as an illustrated journey in picturesque cities of Western and Eastern Europe, North Africa, and North America, sprinkled with historical or philosophical anecdotes and insights.

  15. 15 Jahre Beobachtungen des aktiven Doppelsterns V505 Ser

    NASA Astrophysics Data System (ADS)

    Bernhard, Klaus; Frank, Peter; Huemmerich, Stefan

    2013-03-01

    V505 Ser (GSC 02038-00293) is a short-period eclipsing RS CVn system which was discovered by Bernhard and Frank (2006). It has been the subject of several recent studies which have established physical parameters and distribution of spots (cf. eg. Korhonen et al., 2010; Dal et al., 2012). The present paper gives an overview over recent results from the literature and presents new photometry of V505 Ser which gives further evidence to the existence of a 6-year spot cycle. Klaus Bernhard, Peter Frank and Stefan Huemmerich are member of the BAV.

  16. Tack behavior of coating solutions I.

    PubMed

    Chopra, S K; Tawashi, R

    1982-08-01

    The tackiness of various tablet coating solutions was determined using a parallel plate technique with a tensile testing machine in conjunction with an oscilloscope where the separation force was displayed as a function of time. Measurements were made at various rates of separation on liquid films of constant thickness. Results showed that the force required to split a liquid film increases with an increase in rate of separation, and that tackiness increases with an increase in viscosity. The relation between tack and viscosity was not linear, and a modified Stefan equation was proposed. PMID:7120095

  17. Optical Tracking of Anomalous Diffusion Kinetics in Polymer Microspheres

    NASA Astrophysics Data System (ADS)

    Foreman, Matthew R.; Vollmer, Frank

    2015-03-01

    In this Letter we propose the use of whispering gallery mode resonance tracking as a label-free optical means to monitor diffusion kinetics in glassy polymer microspheres. Approximate solutions to the governing diffusion equations are derived for the case of slow relaxation and small Stefan number. Transduction of physical changes in the polymer, including formation of a rubbery layer, swelling, and dissolution, into detectable resonance shifts are described using a perturbative approach. Concrete examples of poly(methyl methacrylate) and polystyrene spheres in water are considered.

  18. Nonlinear diffusion equations as asymptotic limits of Cahn-Hilliard systems

    NASA Astrophysics Data System (ADS)

    Colli, Pierluigi; Fukao, Takeshi

    2016-05-01

    An asymptotic limit of a class of Cahn-Hilliard systems is investigated to obtain a general nonlinear diffusion equation. The target diffusion equation may reproduce a number of well-known model equations: Stefan problem, porous media equation, Hele-Shaw profile, nonlinear diffusion of singular logarithmic type, nonlinear diffusion of Penrose-Fife type, fast diffusion equation and so on. Namely, by setting the suitable potential of the Cahn-Hilliard systems, all these problems can be obtained as limits of the Cahn-Hilliard related problems. Convergence results and error estimates are proved.

  19. Scale/Analytical Analyses of Freezing and Convective Melting with Internal Heat Generation

    SciTech Connect

    Ali S. Siahpush; John Crepeau; Piyush Sabharwall

    2013-07-01

    Using a scale/analytical analysis approach, we model phase change (melting) for pure materials which generate constant internal heat generation for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. The analysis also consider constant heat flux (in a cylindrical geometry).We show the time scales in which conduction and convection heat transfer dominate.

  20. Mathematical Modeling of Cation Contamination in a Proton-exchange Membrane

    SciTech Connect

    Weber, Adam; Delacourt, Charles

    2008-09-11

    Transport phenomena in an ion-exchange membrane containing both H+ and K+ are described using multicomponent diffusion equations (Stefan-Maxwell). A model is developed for transport through a Nafion 112 membrane in a hydrogen-pump setup. The model results are analyzed to quantify the impact of cation contamination on cell potential. It is shown that limiting current densities can result due to a decrease in proton concentration caused by the build-up of contaminant ions. An average cation concentration of 30 to 40 percent is required for appreciable effects to be noticed under typical steady-state operating conditions.

  1. Tack behavior of coating solutions I.

    PubMed

    Chopra, S K; Tawashi, R

    1982-08-01

    The tackiness of various tablet coating solutions was determined using a parallel plate technique with a tensile testing machine in conjunction with an oscilloscope where the separation force was displayed as a function of time. Measurements were made at various rates of separation on liquid films of constant thickness. Results showed that the force required to split a liquid film increases with an increase in rate of separation, and that tackiness increases with an increase in viscosity. The relation between tack and viscosity was not linear, and a modified Stefan equation was proposed.

  2. Boundary-layer analysis for the convection/diffusion transition in dendritic growth

    NASA Technical Reports Server (NTRS)

    Glicksman, M. E.; Huang, S. C.

    1981-01-01

    The supercooling dependence of dendritic growth kinetics under the influence of convective heat transport is investigated theoretically and experimentally with emphasis on theoretical prediction of the supercooling level at which the transition from diffusion-controlled to convection-controlled dendritic growth occurs. It is shown that the crossover between diffusive and convective transport depends on the relative thickness of the Stefan length compared with the thermal boundary layer. These lengths become equal at a supercooling which may be calculated from diffusion theory and fluid mechanics. It is also shown that the crossover supercooling varies weakly with the gravitational acceleration, melt viscosity, and the volumetric expansion coefficient.

  3. [The problem of reforms in the European medicine between 16th and 19th century in the light of selected concepts of methodology of the history of science].

    PubMed

    Plonka-Syroka, B

    1997-01-01

    The article depicts major concepts present in the contemporary historiography of medicine (positivistic and social-cultural trends) and some of the concepts of modern methodology of the history of science, reviewing the possibilities of its use in the analysis of the process of modernizing the European medicine that was implemented between the 16th and the 19th century. The author advocates the social-cultural trend that dominates the contemporary historiography of medicine. She discusses and analyzes the concepts developed by Ludwik Fleck, Samuel Kuhn, Imre Lakatos, Kurt Godl, Stefan Amsterdamski in respect of their sue to a historian of modern medicine.

  4. Conceptual Commitments of AGI Systems: Editorial, Commentaries, and Response

    NASA Astrophysics Data System (ADS)

    2013-06-01

    Editorial: Conceptual Commitments of AGI Systems Haris Dindo / James Marshall / Giovanni Pezzulo 23 General Problems of Unified Theories of Cognition, and Another Conceptual Commitment of LIDA Benjamin Angerer / Stefan Schneider 26 LIDA, Committed to Consciousness Antonio Chella 28 The Radical Interactionism Conceptual Commitment Olivier L. Georgeon / David W. Aha 31 Commitments of the Soar Cognitive Architecture John E. Laird 36 Conceptual Commitments of AGI Projects Pei Wang 39 Will (dis)Embodied LIDA Agents be Socially Interactive? Travis J. Wiltshire / Emilio J. C. Lobato / Florian G. Jentsch / Stephen M. Fiore 42 Author's Response to Commentaries Steve Strain / Stan Franklin 48

  5. Optical tracking of anomalous diffusion kinetics in polymer microspheres.

    PubMed

    Foreman, Matthew R; Vollmer, Frank

    2015-03-20

    In this Letter we propose the use of whispering gallery mode resonance tracking as a label-free optical means to monitor diffusion kinetics in glassy polymer microspheres. Approximate solutions to the governing diffusion equations are derived for the case of slow relaxation and small Stefan number. Transduction of physical changes in the polymer, including formation of a rubbery layer, swelling, and dissolution, into detectable resonance shifts are described using a perturbative approach. Concrete examples of poly(methyl methacrylate) and polystyrene spheres in water are considered.

  6. Electron-impact-induced tryptophan molecule fragmentation

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

  7. [The centennial of the Department of Microbiology Iaşi--tribute to predecessors].

    PubMed

    Buiuc, D; Pânzaru, Carmen

    2011-01-01

    1892-1913 Bacteriological investigations conducted in Iaşi's hospitals. * 1896 Up to date lectures featuring chapters on microbiology. 1899-1911 The first interim of the Department. 1 februarie 1912 Bacteriology Department de iure et facto: Alexandru Slătineanu. * 1938-39 Second intermediate period. * 1939-1942 Romanian inframicrobiology first started in Iaşi : Stefan S. Nicolau. 1942-1946 Third intermediate period. * 1946 The Bacteriology Department redivivus: Professor Petru Condrea * 1953 The Discipline of Virology: Professor Mihai Duca. PMID:21688589

  8. Slovenian-Romanian bilateral intercomparison on tritium samples.

    PubMed

    Glavič-Cindro, D; Varlam, C; Faurescu, D; Vagner, I; Logar, J Kožar

    2014-05-01

    A Slovenian laboratory from the Jožef Stefan Institute (JSI) and a Romanian laboratory from the National Research and Development Institute for Cryogenics and Isotopic Technologies (ICIT) performed bilateral intercomparisons of tritium determination in environmental samples. On the basis of the results, the measurement and analysis methods were compared. Comparability and traceability were confirmed with the results from international radioactivity proficiency test exercises organized by IAEA and NPL where both laboratories participated. New knowledge gained leads to harmonized, precise and traceable results of low level tritium environmental samples measurements.

  9. The future of electron microscopy

    DOE PAGES

    Zhu, Yimei; Durr, Hermann

    2015-04-01

    Seeing is believing. So goes the old adage and seen evidence is undoubtedly satisfying because it can be interpreted easily, though not always correctly. For centuries, humans have developed such instruments as telescopes that observe the heavens and microscopes that reveal bacteria and viruses. The 2014 Nobel Prize in Chemistry was awarded to Eric Betzig, Stefan Hell, and William Moerner for their foundational work on superresolution fluorescence microscopy in which they overcame the Abbe diffraction limit for the resolving power of conventional light microscopes. (See Physics Today, December 2014, page 18.) That breakthrough enabled discoveries in biological research and testifiesmore » to the importance of modern microscopy.« less

  10. Proton Beam Fast Ignition Fusion: Synergy of Weibel and Rayleigh-Taylor Instabilities

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2011-04-01

    The proton beam generation and focusing in fast ignition inertial confinement fusion is studied. The spatial and energy spread of the proton beam generated in a laser-solid interaction is increased due to the synergy of Weibel and Rayleigh-Taylor instabilities. The focal spot radius can reach 100 μm, which is nearly an order of magnitude larger than the optimal value. The energy spread decreases the beam deposition energy in the focal spot. Under these conditions, ignition of a precompressed DT fuel is achieved with the beam powers much higher than the values presently in consideration. Work supported in part by NIKOLA TESLA Laboratories (Stefan University), La Jolla, CA.

  11. Stem Cell Physics. Multiple-Laser-Beam Treatment of Parkinson's Disease

    NASA Astrophysics Data System (ADS)

    Stefan, V.

    2013-03-01

    A novel method for the treatment of Parkinson's disease is proposed. Pluripotent stem cells are laser cultured, using ultrashort wavelength, (around 0.1 micron-ultraviolet radiation-with intensities of a few mW/cm2) , multiple laser beams.[2] The multiple-energy laser photons[3] interact with the neuron DNA molecules to be cloned. The laser created dopaminergic substantia nigra neurons can be, (theoretically), laser transplanted, (a higher focusing precision as compared to a syringe method), into the striatum or substantia nigra regions of the brain, or both. Supported by Nikola Tesla Labs, Stefan University.

  12. Physics of the Brain: Interaction of the Optical-Fiber-Guided Multi-Ultraviolet-Photon Beams with the Epilepsy Topion, (the Seizure Onset Area)

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    A novel method for the possible prevention of epileptic seizures is proposed, based on the multi-ultraviolet-photon beam interaction with the epilepsy topion, (nonlinear coupling of an ultra high frequency mode to the brain beta phonons). It is hypothesized that epilepsy is a chaotic-dynamics phenomenon: small electrical changes in the epilepsy-topion lead, (within the 10s of milliseconds), to the onset of chaos, (seizure--excessive electrical discharge), and subsequent cascading into adjacent areas. The ultraviolet photons may control the imbalance of sodium and potassium ions and, consequently, may prove to be efficient in the prevention of epileptic seizures. Supported by Nikola Tesla Labs, Stefan University.

  13. Fast Ignition Thermonuclear Fusion: Enhancement of the Pellet Gain by the Colossal-Magnetic-Field Shells

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2013-10-01

    The fast ignition fusion pellet gain can be enhanced by a laser generated B-field shell. The B-field shell, (similar to Earth's B-field, but with the alternating B-poles), follows the pellet compression in a frozen-in B-field regime. A properly designed laser-pellet coupling can lead to the generation of a B-field shell, (up to 100 MG), which inhibits electron thermal transport and confines the alpha-particles. In principle, a pellet gain of few-100s can be achieved in this manner. Supported in part by Nikola Tesla Labs, Stefan University, 1010 Pearl, La Jolla, CA 92038-1007.

  14. The Brain Physics: Multi Laser Beam Interaction with the Brain Topions (the Brain Neurocenters)

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2015-03-01

    A novel method for the treatment of the neurological diseases is proposed. The multiple-energy laser photons (the blue scanning photons and ultraviolet focusing photons) interact with the specific DNA molecules within the topion (such as Parkinson's and Alzheimer's brain topion) via the matching of laser frequency with the oscillation eigen-frequency of a particular molecule within the DNA. In this way, the corrupt molecules (the structure of molecules) can be manipulated so as to treat (eliminate) the neurological disease. Supported by Nikola Tesla Labs, Stefan University.

  15. Evidence-based ergonomics: a model and conceptual structure proposal.

    PubMed

    Silveira, Dierci Marcio

    2012-01-01

    In Human Factors and Ergonomics Science (HFES), it is difficult to identify what is the best approach to tackle the workplace and systems design problems which needs to be solved, and it has been also advocated as transdisciplinary and multidisciplinary the issue of "How to solve the human factors and ergonomics problems that are identified?". The proposition on this study is to combine the theoretical approach for Sustainability Science, the Taxonomy of the Human Factors and Ergonomics (HFE) discipline and the framework for Evidence-Based Medicine in an attempt to be applied in Human Factors and Ergonomics. Applications of ontologies are known in the field of medical research and computer science. By scrutinizing the key requirements for the HFES structuring of knowledge, it was designed a reference model, First, it was identified the important requirements for HFES Concept structuring, as regarded by Meister. Second, it was developed an evidence-based ergonomics framework as a reference model composed of six levels based on these requirements. Third, it was devised a mapping tool using linguistic resources to translate human work, systems environment and the complexities inherent to their hierarchical relationships to support future development at Level 2 of the reference model and for meeting the two major challenges for HFES, namely, identifying what problems should be addressed in HFE as an Autonomous Science itself and proposing solutions by integrating concepts and methods applied in HFES for those problems.

  16. Conversion of UMP, an allosteric inhibitor of carbamyl phosphate synthetase, to an activator by modification of the UMP ribose moiety.

    PubMed

    Boettcher, B; Meister, A

    1981-06-25

    UMP is known to be an allosteric inhibitor of carbamyl phosphate synthetase, whereas IMP activates the enzyme. Surprisingly, dialdehyde UMP (prepared by periodate oxidation of UMP) was found to be a potent activator of the enzyme. Dialdehyde IMP, like IMP, produced activation. The corresponding dialcohol analogs of UMP and IMP (prepared by borohydride reduction of the dialdehyde analogs) had no effect on activity. These nucleotide interactions were further characterized by sedimentation velocity studies and by examination of the effects of inorganic phosphate on enzymatic activity. Although UMP promotes formation of an enzyme dimer, and IMP promotes formation of a tetramer (Powers, S. G., Meister, A., and Haschemeyer, R. H. (1980) J. Biol. Chem. 255, 1554-1558), the dialdehyde analogs of UMP and IMP both promote formation of mixed species. Low levels (less than 10 mM) of inorganic phosphate decrease the extent of activation by IMP, dialdehyde IMP, and dialdehyde UMP, but increase the extent of inhibition by UMP. The marked activation observed with dialdehyde UMP, and other considerations, suggest that the binding sites on the enzyme for IMP and UMP may overlap substantially. The findings also suggest that physiological levels of inorganic phosphate function in the modulation of the allosteric regulation of this enzyme by nucleotides. PMID:7240186

  17. TMD-Based Structural Control of High Performance Steel Bridges

    NASA Astrophysics Data System (ADS)

    Kim, Tae Min; Kim, Gun; Kyum Kim, Moon

    2012-08-01

    The purpose of this study is to investigate the effectiveness of structural control using tuned mass damper (TMD) for suppressing excessive traffic induced vibration of high performance steel bridge. The study considered 1-span steel plate girder bridge and bridge-vehicle interaction using HS-24 truck model. A numerical model of steel plate girder, traffic load, and TMD is constructed and time history analysis is performed using commercial structural analysis program ABAQUS 6.10. Results from analyses show that high performance steel bridge has dynamic serviceability problem, compared to relatively low performance steel bridge. Therefore, the structural control using TMD is implemented in order to alleviate dynamic serviceability problems. TMD is applied to the bridge with high performance steel and then vertical vibration due to dynamic behavior is assessed again. In consequent, by using TMD, it is confirmed that the residual amplitude is appreciably reduced by 85% in steady-state vibration. Moreover, vibration serviceability assessment using 'Reiher-Meister Curve' is also remarkably improved. As a result, this paper provides the guideline for economical design of I-girder using high performance steel and evaluates the effectiveness of structural control using TMD, simultaneously.

  18. DESCRIPTION OF A NEW NAVICULOID DIATOM GENUS MORENEIS GEN. NOV. (BACILLARIOPHYCEAE) FROM SAND FLATS IN KOREA(1).

    PubMed

    Park, Jinsoon; Koh, Chul-Hwan; Khim, Jong Seong; Ohtsuka, Taisuke; Witkowski, Andrzej

    2012-02-01

    This article describes a new diatom genus Moreneis from the Yellow Sea sand flats on the west coast of Korea. The new genus is characterized by a unique combination of morphological characteristics, including the shape of the plastids, which have not been previously observed in diatoms. The valve morphology resembles other genera belonging to Lyrellaceae, within which we place this genus. In terms of areolae structure, Moreneis resembles Petroneis and Placoneis; however, it differs from both genera with respect to the raphe system and plastid shape. Cells of Moreneis spp. have a single large plastid appressed to the girdle of the secondary side of the valve, with two lobes extended toward the primary side of the valve. Furthermore, the unique feature of Moreneis frustules is the raphe, which has both external central and apical endings bent in opposite directions. We differentiated four taxa, which we describe as new for science. However, based on our findings, several established species from Navicula should also be formally transferred to Moreneis, including N. alpha Cleve, N. besarensis Giffen, N. epsilon Cleve, N. menaiana Hendey, N. polae Heiden, and N. quadri-undulata F. Meister. Analysis of published data revealed that species belonging to Moreneis are numerous in tropical marine littoral waters, and in moderate climate zones, especially in the western Pacific, with only a few species occurring in the Mediterranean and Atlantic. PMID:27009663

  19. Artificial retina: the multichannel processing of the mammalian retina achieved with a neuromorphic asynchronous light acquisition device.

    PubMed

    Lorach, Henri; Benosman, Ryad; Marre, Olivier; Ieng, Sio-Hoi; Sahel, José A; Picaud, Serge

    2012-12-01

    Objective. Accurate modeling of retinal information processing remains a major challenge in retinal physiology with applications in visual rehabilitation and prosthetics. Most of the current artificial retinas are fed with static frame-based information, losing thereby the fundamental asynchronous features of biological vision. The objective of this work is to reproduce the spatial and temporal properties of the majority of ganglion cell (GC) types in the mammalian retina. Approach. Here, we combined an asynchronous event-based light sensor with a model pulling nonlinear subunits to reproduce the parallel filtering and temporal coding occurring in the retina. We fitted our model to physiological data and were able to reconstruct the spatio-temporal responses of the majority of GC types previously described in the mammalian retina (Roska et al 2006 J. Neurophysiol. 95 3810-22). Main results. Fitting of the temporal and spatial components of the response was achieved with high coefficients of determination (median R(2) = 0.972 and R(2) = 0.903, respectively). Our model provides an accurate temporal precision with a reliability of only few milliseconds-peak of the distribution at 5 ms-similar to biological retinas (Berry et al 1997 Proc. Natl Acad. Sci. USA 94 5411-16; Gollisch and Meister 2008 Science 319 1108-11). The spiking statistics of the model also followed physiological measurements (Fano factor: 0.331). Significance. This new asynchronous retinal model therefore opens new perspectives in the development of artificial visual systems and visual prosthetic devices.

  20. Bounds on Elastic Constants for Random Polycrystals of Laminates

    SciTech Connect

    Berryman, J G

    2004-04-30

    A well-known result due to Hill provides an exact expression for the bulk modulus of any multicomponent elastic composite whenever the constituents are isotropic and the shear modulus is uniform throughout. Although no precise analog of Hill's result is available for the opposite case of uniform bulk modulus and varying shear modulus, it is shown here that some similar statements can be made for shear behavior of random polycrystals composed of laminates of isotropic materials. In particular, the Hashin-Shtrikman-type bounds of Peselnick, Meister, and Watt for random polycrystals composed of hexagonal (transversely isotropic) grains are applied to the problem of polycrystals of laminates. An exact product formula relating the Reuss estimate of bulk modulus and an effective shear modulus (of laminated grains composing the system) to products of the eigenvalues for quasi-compressional and quasi-uniaxial shear eigenvectors also plays an important role in the analysis of the overall shear behavior of the random polycrystal. When the bulk modulus is uniform in such a system, the equations are shown to reduce to a simple form that depends prominently on the uniaxial shear eigenvalue - as expected from physical arguments concerning the importance of uniaxial shear in these systems. One application of the analytical results presented here is for benchmarking numerical procedures used for estimating elastic behavior of complex composites.

  1. Differential leaching of nutrients from soluble vs. controlled-release fertilizers

    NASA Astrophysics Data System (ADS)

    Alva, Ashok K.

    1992-11-01

    Extremely sandy soils and poorly distributed high annual rainfall in the state of Florida contribute to significant leaching losses of nutrients from routine fertilization practices. A leaching column experiment was conducted to evaluate the leaching losses of nutrients when using currently available N, P, K blend fertilizers for young citrus tree fertilization. Fertilizer blends included NH4NO3, Ca(NO3)2, IBDU, IBDU plus Escote, Nutralene, Osmocote, and Meister. Following leaching of 1000 ml of water through soil columns, which simulates leaching conditions with 26 cm of rainfall, the amount of NO3 and NH4 recovered in the leachate from soil columns amended with an NH4NO3 blend accounted for 37% and 88% of the respective nutrients contained in the quantity of blend per column. The corresponding values for soil columns amended with a Ca(NO3)2 blend were 48% and 100%. Leraching losses of both NO3 (<3%) and NH4 (<4%) were drastically decreased when using controlled-release fertilizers. The recoveries of P and K in 1000 ml of leachate were 1.3% and 8%, respectively, of the nutrients added as Osmocote, which contained coated P and K sources. In the case of the rest of fertilizer blends, the recoveries of P and K in 1000 ml of leachate were as high as 52%-100% and 28%-100%, respectively. Therefore, controlled-release technology offers an important capability for minimizing leaching losses of nutrients.

  2. Modeling study of the influence of mixing on the fluxes of nutrients through the water column redox-interfaces

    NASA Astrophysics Data System (ADS)

    Yakushev, E.

    2009-04-01

    In this study we used a coupled hydrophysical-biogeochemical O-N-S-P-Mn-Fe- model based on ROLM (Yakushev et al., 2007) and GOTM (Burchard et al., 2006). Processes of organic matter (OM) formation and decay, the reduction and oxidation of species of nitrogen, sulphur, manganese, iron, as well as transformation of phosphorus species are parameterized. The model considered phytoplankton, zooplankton and bacteria. The model allowed to simulate the main features of the vertically balanced biogeochemical structure of the redox interfaces (i.e observed in the Black Sea, Gotland Deep, Oslo Fjord). Numerical experiments allowed to demonstrate how the changes in vertical mixing (from Kz=10-6 m2s-1 to Kz=10-4 m2s-1) affect the distributions of the considered parameters and the rates of their transformation. The received estimates allowed to analyze the influence of the water column redox interfaces on the fluxes of nutrients, in particular phosphate, in different conditions. Burchard, H., Bolding, K., Kuehn, W., Meister, A., Neumann, T., Umlauf, L. 2006. Description of a flexible and extendable physical-biogeochemical model system for the water column. J.of Mar.Sys., 61: 180-211. Yakushev E.V., Pollehne F., Jost G. et al. 2007. Analysis of the water column oxic/anoxic interface in the Black and Baltic seas with a Redox-Layer Model. Mar. Chem., 107: 388-410.

  3. On the number density of "direct collapse" black hole seeds

    NASA Astrophysics Data System (ADS)

    Habouzit, Mélanie; Volonteri, Marta; Latif, Muhammad; Dubois, Yohan; Peirani, Sébastien

    2016-08-01

    Supermassive black holes (BHs) reside in the center of most local galaxies, but they also power active galactic nuclei and quasars, detected up to z = 7. These quasars put constraints on early BH growth and the mass of BH seeds. The scenario of "direct collapse" is appealing as it leads to the formation of large mass BH seeds, 10^4-10^6 {M_{⊙}}, which eases explaining how quasars at z = 6 - 7 are powered by BHs with masses >109 M⊙. Direct collapse, however, appears to be rare, as the conditions required by the scenario are that gas is metal-free, the presence of a strong photo-dissociating Lyman-Werner flux, and large inflows of gas at the center of the halo, sustained for 10 - 100 Myr. We performed several cosmological hydrodynamical simulations that cover a large range of box sizes and resolutions, thus allowing us to understand the impact of several physical processes on the distribution of direct collapse BHs. We identify halos where direct collapse can happen, and derive the number density of BHs. We also investigate the discrepancies between hydrodynamical simulations, direct or post-processed, and semi-analytical studies. Under optimistic assumptions, we find that for direct collapse to account for BHs in normal galaxies, the critical Lyman-Werner flux required for direct collapse must be about two orders of magnitude lower than predicted by 3D simulations that include detailed chemical models. However, when supernova feedback is relatively weak, enough direct collapse BHs to explain z = 6 - 7 quasars can be obtained for Lyman-Werner fluxes about one order of magnitude lower than found in 3D simulations.

  4. On the number density of `direct collapse' black hole seeds

    NASA Astrophysics Data System (ADS)

    Habouzit, Mélanie; Volonteri, Marta; Latif, Muhammad; Dubois, Yohan; Peirani, Sébastien

    2016-11-01

    Supermassive black holes (BHs) reside in the centre of most local galaxies, but they also power active galactic nuclei and quasars, detected up to z = 7. These quasars put constraints on early BH growth and the mass of BH seeds. The scenario of `direct collapse' is appealing as it leads to the formation of large mass BH seeds, 104-106 M⊙, which eases explaining how quasars at z = 6-7 are powered by BHs with masses >109 M⊙. Direct collapse, however, appears to be rare, as the conditions required by the scenario are that gas is metal-free, the presence of a strong photodissociating Lyman-Werner flux, and large inflows of gas at the centre of the halo, sustained for 10-100 Myr. We performed several cosmological hydrodynamical simulations that cover a large range of box sizes and resolutions, thus allowing us to understand the impact of several physical processes on the distribution of direct collapse BHs. We identify haloes where direct collapse can happen, and derive the number density of BHs. We also investigate the discrepancies between hydrodynamical simulations, direct or post-processed, and semi-analytical studies. Under optimistic assumptions, we find that for direct collapse to account for BHs in normal galaxies, the critical Lyman-Werner flux required for direct collapse must be about two orders of magnitude lower than predicted by 3D simulations that include detailed chemical models. However, when supernova feedback is relatively weak, enough direct collapse BHs to explain z = 6-7 quasars can be obtained for Lyman-Werner fluxes about one order of magnitude lower than found in 3D simulations.

  5. Retention time of rays around small lunar craters

    NASA Astrophysics Data System (ADS)

    Suzuki, S.; Honda, C.; Hirata, N.; Asada, N.; Demura, H.; Kitazato, K.; Ogawa, Y.; Terazono, J.; Moroda, T.; Ohtake, M.; Haruyama, J.; Matsunaga, T.

    2010-12-01

    Fresh lunar impact craters have rays which are bright features radially expanding from host craters. It has been suggested that the rays are erased by space weathering that modify surface materials by exposure to solar wind and micrometeorite bombardments, and by impact gardening that mixes surface materials and subsurface materials by meteorite bombardments (Wilhelms, 1987). Werner and Medvedev (2010) surveyed lunar rayed craters with Clementine UVVIS images and showed that retention time of the rays of craters larger than 5 km in diameter is 750 Myr. The purpose of this research is to estimate the retention time of rays around smaller lunar craters with high-resolution multiband images from Kaguya/MI (Multiband Imager). In our research, we surveyed rayed craters using OMAT (Optical Maturity) parameter developed by Lucey et al. (2000). The OMAT parameter is the optical index representing the degree of space weathering, which is derived from multiband images. Crater rays are not only bright, but also have larger OMAT value than the background. We conducted a survey of rayed craters from 300 m to 2 km in diameter in lunar highland with MI images and MI-OMAT data. A crater size-frequency distribution (CSFD) plot is constructed for detected small rayed craters. Our preliminary result suggest that the CSFD of the rayed craters of less than 1 km in diameter falls beneath an isochrone 750 Ma, the ray retention time for large craters estimated by Werner and Medvedev (2010). This result supports an idea that the retention time of rayes depends on the crater diameter (Werner and Medvedev, 2010). Smaller craters would show shorter ray retention times.

  6. Probabilistically Constraining Age-Depth-Models of Glaciogenic Sediments

    NASA Astrophysics Data System (ADS)

    Werner, J.; van der Bilt, W.; Tingley, M.

    2015-12-01

    Reconstructions of the late-Holocene climate rely heavily upon proxies that are assumed to be accurately dated by layer counting. All of these proxies, such as measurements of tree rings, ice cores, and varved lake sediments do carry some inherent dating uncertainty that is not always fully accounted for. Considerable advances could be achieved if time uncertainties were recognized and correctly modeled, also for proxies commonly treated as free of age model errors. Current approaches for accounting for time uncertainty are generally limited to repeating the reconstruction using each one of an ensemble of age models, thereby inflating the final estimated uncertainty - in effect, each possible age model is given equal weighting. Uncertainties can be reduced by exploiting the inferred space-time covariance structure of the climate to re-weight the possible age models. Werner and Tingley (2015) demonstrated how Bayesian hierarchical climate reconstruction models can be augmented to account for time-uncertain proxies. In their method, probabilities associated with the age models are formally updated within the Bayesian framework, thereby reducing uncertainties. Numerical experiments (Werner and Tingley 2015) show that updating the age model probabilities decreases uncertainty in the resulting reconstructions, as compared with the current de facto standard of sampling over all age models, provided there is sufficient information from other data sources in the spatial region of the time-uncertain proxy. We show how this novel method can be applied to high resolution, sub-annually sampled lacustrine sediment records to constrain their respective age depth models. The results help to quantify the signal content and extract the regionally representative signal. The single time series can then be used as the basis for a reconstruction of glacial activity. van der Bilt et al. in prep. Werner, J.P. and Tingley, M.P. Clim. Past (2015)

  7. Understanding Vascular Diseases: Lessons From Premature Aging Syndromes.

    PubMed

    Ikeda, Yuichi; Kumagai, Hidetoshi; Motozawa, Yoshihiro; Suzuki, Jun-Ichi; Akazawa, Hiroshi; Komuro, Issei

    2016-05-01

    Early human mummies examined recently by computed tomography demonstrated a high prevalence of vascular calcification, a pathognomonic sign of atherosclerosis, which was correlated with estimated age at death. Early populations had little exposure to modern-day metabolic risk factors: these observations thus suggest that humans have an inherent age-dependent predisposition to atherosclerosis. Premature aging syndromes are extremely rare genetic disorders that exhibit clinical phenotypes resembling accelerated aging, including severe atherosclerosis, but those phenotypes are usually segmental. Controversy persists, therefore, regarding the extent to which the molecular mechanisms underlying premature aging syndromes overlap with those of physiological aging. Hutchinson-Gilford progeria syndrome (HGPS) and Werner syndrome are well-characterized premature aging syndromes. HGPS is caused by gain-of-function mutations in the LMNA gene, which result in the accumulation of a mutant nuclear protein, called "progerin," at the nuclear rim. In contrast, loss-of-function mutations in Werner syndrome ATP-dependent helicase (WRN) lead to Werner syndrome. Mesenchymal stem cells (MSCs), which can differentiate into vascular cells to maintain vascular homeostasis in response to injury, are severely affected in these syndromes. Mechanistically, either aberrant expression of progerin or loss of WRN protein in MSCs alters heterochromatin structure, resulting in premature senescence and exhaustion of functional MSCs in premature aging syndromes. Surprisingly, vascular cells and MSCs in elderly healthy individuals have shown progerin expression and decreased expression levels of WRN, respectively. Studying these rare genetic disorders could thus provide valuable insights into age-related vascular diseases that occur in the general population. PMID:26948039

  8. VizieR Online Data Catalog: Infrared photometry of Galactic and MC PN (Phillips+, 2009)

    NASA Astrophysics Data System (ADS)

    Phillips, J. P.; Ramos-Larios, G.

    2015-07-01

    We have acquired photometry and mapping of a wide range of Galactic disc, Galactic bulge, and LMC PNe using data deriving from the second Galactic Legacy Infrared Mid-plane Survey Extraordinaire (GLIMPSE II) (Benjamin et al., 2003PASP..115..953B, Cat. II/293), and the program Surveying the Agents of a Galaxy.s Evolution (SAGE; Meixner et al., 2006AJ....132.2268M, Cat. J/AJ/132/2268). Both of these surveys were undertaken using the Spitzer Space Telescope (SST; Werner et al., 2004ApJS..154....1W). (3 data files).

  9. Complete genome sequence of Odoribacter splanchnicus type strain (1651/6T)

    SciTech Connect

    Goker, Markus; Gronow, Sabine; Zeytun, Ahmet; Nolan, Matt; Lucas, Susan; Lapidus, Alla L.; Hammon, Nancy; Deshpande, Shweta; Cheng, Jan-Fang; Pitluck, Sam; Liolios, Konstantinos; Pagani, Ioanna; Ivanova, N; Mavromatis, K; Ovchinnikova, Galina; Pati, Amrita; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne A.; Chen, Amy; Palaniappan, Krishna; Land, Miriam L; Hauser, Loren John; Jeffries, Cynthia; Brambilla, Evelyne-Marie; Rohde, Christine; Detter, J. Chris; Woyke, Tanja; Bristow, James; Markowitz, Victor; Hugenholtz, Philip; Eisen, Jonathan; Kyrpides, Nikos C; Klenk, Hans-Peter

    2011-01-01

    Odoribacter splanchnicus (Werner et al. 1975) Hardham et al. 2008 is the type species of the genus Odoribacter, which belongs to the family Porphyromonadaceae in the order Bacteroidales . The species is of interest because members of the Odoribacter form an isolated cluster within the Porphyromonadaceae. This is the first completed genome sequence of a member of the genus Odoribacter and the fourth sequence from the family Porphyromonadaceae. The 4,392,288 bp long genome with its 3,672 protein-coding and 74 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  10. Environment-assisted error correction of single-qubit phase damping

    NASA Astrophysics Data System (ADS)

    Trendelkamp-Schroer, Benjamin; Helm, Julius; Strunz, Walter T.

    2011-12-01

    Open quantum system dynamics of random unitary type may in principle be fully undone. Closely following the scheme of environment-assisted error correction proposed by Gregoratti and Werner [J. Mod. Opt.10.1080/09500340308234541 50, 915 (2003)], we explicitly carry out all steps needed to invert a phase-damping error on a single qubit. Furthermore, we extend the scheme to a mixed-state environment. Surprisingly, we find cases for which the uncorrected state is closer to the desired state than any of the corrected ones.

  11. [Blister dermatitis caused by Epicauta flagellaria (Erichson) (Coleoptera: Meloidae) species].

    PubMed

    Méndez, E; Sáenz, R E; Johnson, C M

    1989-09-01

    This paper is the first published report of vesicular dermatitis due to blister beetles of the family Meloidae in Panamá. A familial outbreak of bullous dermatitis caused by Epicauta flagellaria (Erichson) is described. All previous cases known in the Gorgas Memorial Laboratory were associated with E. isthmica Werner. Bullous lesions are produced when cantharidin, a vesicating toxin contained in the beetle's body, is released at the time the insect is crushed or rubbed upon the exposed skin. Rules for the treatment and prevention of this disease are indicated.

  12. Student Interns Share the Spirit of Science | Poster

    Cancer.gov

    They came for a science lesson. They left with more. The new Werner H. Kirsten student interns filed into the auditorium in Building 549 to expand their knowledge of fundamental laboratory practices, as part of the Science Skills Boot Camp. A panel of presenters instructed the attendees on skills such as reading scientific papers effectively, practicing proper research ethics, and conducting professional presentations. Scientific Program Manager Ulrike Klenke, Ph.D., NIH Office of Intramural Training and Education, started the June event by welcoming her audience and encouraging the interns to break away from their familiar groups of classmates and to socialize with others from different schools and counties.

  13. Former Intern: Skills Used For a Lifetime | Poster

    Cancer.gov

    Michelle Marcelino developed a strong interest in science as a child. The former Werner H. Kirsten student intern’s father was a physicist and often discussed with his daughters how the world works in terms of science. “I think my father instilled it in me from a very young age,” Marcelino said. “I remember being in elementary school and my father telling us colors are just wavelengths of light perceived by your eye. That’s my dad, explaining that concept in detail to a child.” 

  14. Environment-assisted error correction of single-qubit phase damping

    SciTech Connect

    Trendelkamp-Schroer, Benjamin; Helm, Julius; Strunz, Walter T.

    2011-12-15

    Open quantum system dynamics of random unitary type may in principle be fully undone. Closely following the scheme of environment-assisted error correction proposed by Gregoratti and Werner [J. Mod. Opt. 50, 915 (2003)], we explicitly carry out all steps needed to invert a phase-damping error on a single qubit. Furthermore, we extend the scheme to a mixed-state environment. Surprisingly, we find cases for which the uncorrected state is closer to the desired state than any of the corrected ones.

  15. Generalized X states of N qubits and their symmetries

    SciTech Connect

    Vinjanampathy, Sai; Rau, A. R. P.

    2010-09-15

    Several families of states such as Werner states, Bell-diagonal states, and Dicke states are useful in understanding multipartite entanglement. Here we present a (2{sup N+1}-1)-parameter family of N-qubit ''X states'' that embraces all those families, generalizing previously defined states for two qubits. We also present the algebra of the operators that characterize the states and an iterative construction for this algebra, a subalgebra of su(2{sup N}). We show how a variety of entanglement witnesses can detect entanglement in such states. Connections are also made to structures in projective geometry.

  16. Three new species of tiger beetles and new data on Cicindelina species from Angola (Coleoptera: Carabidae: Cicindelinae).

    PubMed

    Serrano, Artur R M; Capela, Rúben A; Oesterle, Andreas

    2015-10-15

    Three new species of tiger beetles, two of the genus Trichotaenia Rivalier, 1957 and one of the genus Cylindera Westwood, 1831, subgenus Ifasina Jeannel, 1946 are described from Angola. An annotated list of species of Cicindelina sampled in this country is provided also. Records for three species previously unknow from Angola are given: Ophryodera smrzi Werner, 2005, Lophyra clatharta (Dejean, 1825) and Lophyra sumlini Cassola, 1976. Some considerations on the distribution and general ecology of these beetles in Angola are also presented. Further, two dichotomic keys are made available for the identification of Trichotaenia species with marked shoulders and Cylindera (Ifasina) species of western and southwestern Africa, respectively.

  17. Orbicular granite near Jelenia Góra in southwestern Poland: the first outcrops?

    NASA Astrophysics Data System (ADS)

    Kennan, Pádhraig S.; Lorenc, Marek W.

    2008-01-01

    In 1802, Leopold von Buch described some outcrops of orbicular granite in the Karkonosze granite, Lower Silesia, Poland. In that publication, Abraham Gottlieb Werner wrote a foreword dated 1800. The Silesian discovery predates that of the well-known orbicular diorite (Napoleonite) in outcrop on Corsica and, thus, may be the first ever record of this distinctive rock type in its geological context. The characterizing, closely-packed, simple orbs comprise K-feldspar cores surrounded by rims of radiating K-feldspar and quartz. Rapid growth from a hydrous, pegmatitic melt is indicated. The Karkonosze outcrop, in the timing of its discovery, is a unique part of the geological heritage.

  18. Entangled mixed-state generation by twin-photon scattering

    SciTech Connect

    Puentes, G.; Aiello, A.; Woerdman, J. P.; Voigt, D.

    2007-03-15

    We report experimental results on mixed-state generation by multiple scattering of polarization-entangled photon pairs created from parametric down-conversion. By using a large variety of scattering optical systems we have experimentally obtained entangled mixed states that lie upon and below the Werner curve in the linear entropy-tangle plane. We have also introduced a simple phenomenological model built on the analogy between classical polarization optics and quantum maps. Theoretical predictions from such a model are in full agreement with our experimental findings.

  19. Atmospheric Radiation Measurement (ARM) Data from Steamboat Springs, Colorado, for the Storm Peak Laboratory Cloud Property Validation Experiment (STORMVEX)

    DOE Data Explorer

    In October 2010, the initial deployment of the second ARM Mobile Facility (AMF2) took place at Steamboat Springs, Colorado, for the Storm Peak Laboratory Cloud Property Validation Experiment (STORMVEX). The objective of this field campaign was to obtain data about liquid and mixed-phase clouds using AMF2 instruments in conjunction with Storm Peak Laboratory (located at an elevation of 3220 meters on Mt. Werner), a cloud and aerosol research facility operated by the Desert Research Institute. STORMVEX datasets are freely available for viewing and download. Users are asked to register with the ARM Archive; the user's email address is used from that time forward as the login name.

  20. Celebrating 25 Years of Student Mentoring | Poster

    Cancer.gov

    Most employees of NCI at Frederick have heard of the Werner H. Kirsten Student Intern Program (WHK SIP). The reason is simple—it has been wildly successful. And on Friday, April 22, the program will celebrate 25 years of mentoring and learning at the WHK SIP 25th Anniversary Symposium and Awards Ceremony. During the morning session, several former interns will talk about the impact that the WHK program has had on their lives. The afternoon session will begin with a panel of current and former mentors who will answer questions from students interested in the program and staff members interested in becoming mentors. Read more...

  1. Students Share Their Research at Student Poster Day | Poster

    Cancer.gov

    Students Share Their Research at Student Poster Day  By Ashley DeVine, Staff Writer More than 50 Werner H. Kirsten student interns and college interns presented their research at Summer Student Poster Day on August 6 in the Building 549 lobby.  Joseph Bergman, a high school intern in the Center for Cancer Research Nanobiology Laboratory, participated in the event “for the opportunity to present my summer research. It allowed me to meet people and get the experience of sharing and explaining my work.”

  2. Poster Day Showcases Student Work | Poster

    Cancer.gov

    By Nathalie Walker, Guest Writer, and Carolynne Keenan, Contributing Writer On July 31, NCI at Frederick hosted Student Poster Day, an annual event in which student interns can showcase the work they do in their various positions in NCI at Frederick labs and offices. Participating students are interns in the Student Internship Program, a program designed for undergraduate and graduate students during their summer breaks, as well as interns in the Werner H. Kirsten Student Internship Program (WHK SIP), a program for high school seniors. All the students have an opportunity to present their scientific posters.

  3. Local, nonlocal quantumness and information theoretic measures

    NASA Astrophysics Data System (ADS)

    Agrawal, Pankaj; Sazim, Sk; Chakrabarty, Indranil; Pati, Arun K.

    2016-08-01

    It has been suggested that there may exist quantum correlations that go beyond entanglement. The existence of such correlations can be revealed by information theoretic quantities such as quantum discord, but not by the conventional measures of entanglement. We argue that a state displays quantumness, that can be of local and nonlocal origin. Information theoretic measures not only characterize the nonlocal quantumness, but also the local quantumness, such as the “local superposition”. This can be a reason, why such measures are nonzero, when there is no entanglement. We consider a generalized version of the Werner state to demonstrate the interplay of local quantumness, nonlocal quantumness and classical mixedness of a state.

  4. Non-Markovian effect on the quantum discord

    SciTech Connect

    Wang Bo; Xu Zhenyu; Chen Zeqian; Feng Mang

    2010-01-15

    We study the non-Markovian effect on the dynamics of the quantum discord by exactly solving a model consisting of two independent qubits subject to two zero-temperature non-Markovian reservoirs, respectively. Considering the two qubits initially prepared in Bell-like or extended Werner-like states, we show that there is no occurrence of the sudden death, but only instantaneous disappearance of the quantum discord at some time points, in comparison to the entanglement sudden death in the same range of the parameters of interest. This implies that the quantum discord is more useful than the entanglement to describe the quantum correlation involved in quantum systems.

  5. Bell pair in a generic random matrix environment

    NASA Astrophysics Data System (ADS)

    Pineda, Carlos; Seligman, Thomas H.

    2007-01-01

    Two noninteracting qubits are coupled to an environment. Both coupling and environment are chosen as random matrices to obtain generic results. The initial state of the pair ranges from a Bell state to a product state. Decoherence of the pair is evaluated analytically in terms of purity; Monte Carlo calculations confirm these results and also yield concurrence of the pair. Entanglement within the pair accelerates decoherence. Numerics displays the relation between concurrence and purity known for Werner states. A closed albeit heuristic formula for concurrence decay ensues.

  6. The STIR sequence MRI in the assessment of extraocular muscles in thyroid eye disease.

    PubMed

    Hoh, H B; Laitt, R D; Wakeley, C; Kabala, J; Goddard, P; Potts, M J; Harrad, R A

    1994-01-01

    Nineteen patients with thyroid eye disease were examined with magnetic resonance imaging using the Short Tau Inversion Recovery (STIR) sequence and compared with normal controls. The Signal Intensity Ratio (SIR) of each of the four recti was obtained by comparison with the signal intensity of the adjacent temporalis muscle. The SIR was compared with disease activity assessed using Werner's grading system, a clinical inflammatory score, and the range of extraocular movements. Results show that a high SIR is associated with a high index of disease activity. This technique is likely to prove useful in assessing disease activity and planning the management of thyroid eye disease, particularly with respect to immunosuppression.

  7. Global quantum discord in multipartite systems

    SciTech Connect

    Rulli, C. C.; Sarandy, M. S.

    2011-10-15

    We propose a global measure for quantum correlations in multipartite systems, which is obtained by suitably recasting the quantum discord in terms of relative entropy and local von Neumann measurements. The measure is symmetric with respect to subsystem exchange and is shown to be nonnegative for an arbitrary state. As an illustration, we consider tripartite correlations in the Werner-GHZ (Greenberger-Horne-Zeilinger) state and multipartite correlations at quantum criticality. In particular, in contrast with the pairwise quantum discord, we show that the global quantum discord is able to characterize the infinite-order quantum phase transition in the Ashkin-Teller spin chain.

  8. Transcatheter intervention for the treatment of congenital cardiac defects.

    PubMed Central

    Grifka, R G

    1997-01-01

    Cardiac catheterization has an illustrious history, originating in 1929 when Werner Forsmann, a surgical resident, performed a heart catheterization on himself. Transcatheter interventional procedures have been performed since the 1960s. The 1st intracardiac procedure to become standard therapy was a balloon atrial septostomy. Skeptics attacked this innovative procedure. However, the balloon septostomy procedure soon became the standard emergency procedure for certain congenital heart defects, and was the impetus for other investigators in the field of transcatheter intervention. We will discuss transcatheter treatment for congenital vascular stenoses and vascular occlusion. Images PMID:9456482

  9. Robust state transfer in the quantum spin channel via weak measurement and quantum measurement reversal

    NASA Astrophysics Data System (ADS)

    He, Zhi; Yao, Chunmei; Zou, Jian

    2013-10-01

    Using the weak measurement (WM) and quantum measurement reversal (QMR) approach, robust state transfer and entanglement distribution can be realized in the spin-(1)/(2) Heisenberg chain. We find that the ultrahigh fidelity and long distance of quantum state transfer with certain success probability can be obtained using proper WM and QMR, i.e., the average fidelity of a general pure state from 80% to almost 100%, which is almost size independent. We also find that the distance and quality of entanglement distribution for the Bell state and the general Werner mixed state can be obviously improved by the WM and QMR approach.

  10. Geometric measure of pairwise quantum discord for superpositions of multipartite generalized coherent states

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Ahl Laamara, R.

    2012-07-01

    We give the explicit expressions of the pairwise quantum correlations present in superpositions of multipartite coherent states. A special attention is devoted to the evaluation of the geometric quantum discord. The dynamics of quantum correlations under a dephasing channel is analyzed. A comparison of geometric measure of quantum discord with that of concurrence shows that quantum discord in multipartite coherent states is more resilient to dissipative environments than is quantum entanglement. To illustrate our results, we consider some special superpositions of Weyl-Heisenberg, SU(2) and SU(1,1) coherent states which interpolate between Werner and Greenberger-Horne-Zeilinger states.

  11. Decoherence Effect on Quantum Correlation and Entanglement in a Two-qubit Spin Chain

    NASA Astrophysics Data System (ADS)

    Pourkarimi, Mohammad Reza; Rahnama, Majid; Rooholamini, Hossein

    2015-04-01

    Assuming a two-qubit system in Werner state which evolves in Heisenberg XY model with Dzyaloshinskii-Moriya (DM) interaction under the effect of different environments. We evaluate and compare quantum entanglement, quantum and classical correlation measures. It is shown that in the absence of decoherence effects, there is a critical value of DM interaction for which entanglement may vanish while quantum and classical correlations do not. In the presence of environment the behavior of correlations depends on the kind of system-environment interaction. Correlations can be sustained by manipulating Hamiltonian anisotropic-parameter in a dissipative environment. Quantum and classical correlations are more stable than entanglement generally.

  12. Finite-Temperature Entanglement Dynamics in an Anisotropic Two-Qubit Heisenberg Spin Chain

    NASA Astrophysics Data System (ADS)

    Chen, Tao; Shan, Chuanjia; Li, Jinxing; Liu, Tangkun; Huang, Yanxia; Li, Hong

    2010-07-01

    This paper investigates the entanglement dynamics of an anisotropic two-qubit Heisenberg spin chain in the presence of decoherence at finite temperature. The time evolution of the concurrence is studied for different initial Werner states. The influences of initial purity, finite temperature, spontaneous decay and Hamiltonian on the entanglement evolution are analyzed in detail. Our calculations show that the finite temperature restricts the evolution of the entanglement all the time when the Hamiltonian improves it and the spontaneous decay to the reservoirs can produce quantum entanglement with the anisotropy of spin-spin interaction. Finally, the steady-state concurrence which may remain non-zero for low temperature is also given.

  13. GENERAL: Entanglement sudden death induced by the Dzialoshinskii-Moriya interaction

    NASA Astrophysics Data System (ADS)

    Zeng, Hong-Fang; Shao, Bin; Yang, Lin-Guang; Li, Jian; Zou, Jian

    2009-08-01

    In this paper, we study the entanglement dynamics of two-spin Heisenberg XYZ model with the Dzialoshinskii-Moriya (DM) interaction. The system is initially prepared in the Werner state. The effects of purity of the initial state and DM coupling parameter on the evolution of entanglement are investigated. The necessary and sufficient condition for the appearance of the entanglement sudden death (ESD) phenomenon has been deduced. The result shows that the ESD always occurs if the initial state is sufficiently impure for the given coupling parameter or the DM interaction is sufficiently strong for the given initial state. Moreover, the critical values of them are calculated.

  14. Mathematics, Experiments, and Theoretical Physics: The Early Days of the Sommerfeld School

    NASA Astrophysics Data System (ADS)

    Eckert, Michael

    1999-10-01

    The names of his students read like a Who's Who of the pioneers in modern physics Peter Debye, Peter Paul Ewald, Wolfgang Pauli, Werner Heisenberg, Hans A. Bethe - to name only the most prominent. In retrospect, the success of Sommerfeld's school of modern theoretical physics tends to overshadow its less glorious beginnings. A century ago, theoretical physics was not yet considered as a distinct discipline. In this article I emphasize more the haphazard beginnings than the later achievements of Sommerfeld's school, which mirrored the state of theoretical physics before it became an independent discipline.

  15. VizieR Online Data Catalog: Mid-IR QSO spectral templates (Hill+, 2014)

    NASA Astrophysics Data System (ADS)

    Hill, A. R.; Gallagher, S. C.; Deo, R. P.; Peeters, E.; Richards, G. T.

    2014-11-01

    We coordinate cross matched the SDSS quasar catalogue (Schneider et al., 2010AJ....139.2360S, Cat. VII/260) with the Spitzer (Werner et al. 2004ApJS..154....1W) Infrared Spectrograph (IRS) archive, using a match radius of 2 arcsec, yielding 184 low-resolution (R~60-130) MIR spectra. We selected all data which had short-low (SL; 5.1-14.3um) and/or long-low (LL; 13.9-39.9um) modules (although not all objects necessarily had both modules), opting to keep only the low-resolution data. (2 data files).

  16. Using Xenopus skin to study cilia development and function.

    PubMed

    Werner, Michael E; Mitchell, Brian J

    2013-01-01

    Cilia are prevalent biological structures that are important for cell signaling and for generating fluid flow (or motility). Cilia are found throughout biology from single-celled organisms to vertebrates, and many model systems have been employed for their analysis. Here, we describe the use of Xenopus larval skin as a system for the study of ciliogenesis and ciliary function. In particular, we describe basic molecular and embryological manipulations and imaging techniques that have proven particularly useful for understanding the polarized beating of cilia and the generation of directed fluid flow (Werner & Mitchell, 2012). However, these same tools have the potential to benefit a large number of cilia-related biological questions.

  17. Former Intern: Amy Stull Returns to Her Roots | Poster

    Cancer.gov

    By Carolynne Keenan, Contributing Writer When Amy Stull, a 2000 graduate of Walkersville High School, began working in a laboratory at the National Cancer Institute (NCI) at Frederick, she likely did not know the role NCI would play in her career. Stull started at NCI as a Werner H. Kirsten (WHK) student intern after her junior year of high school, working in a lab as she prepared for a career in chemical engineering. The student intern program pairs rising high school seniors with laboratory scientists to encourage the students to pursue careers in both science and health care fields.

  18. First hand accounts of events in the laboratory of Prof. Eduard Pernkopf. Interviews by Seyed Hossein Aharinejad and Stephen W Carmichael.

    PubMed

    Kraus, Walter; Gisel, Alfred; Platzer, Werner

    2013-04-01

    Eduard Pernkopf was responsible for one of the best anatomy atlases of all time. He was also an active National Socialist during the Third Reich. Some have questioned whether his political affiliation influenced the procurement of anatomic specimens for his Atlas. Profs. Walter Kraus, Alfred Gisel, and Werner Platzer, who worked directly or indirectly with Pernkopf, were interviewed in 2006. We present transcripts of those interviews. The reader may evaluate their recollections in light of the political and social forces active in that period of history.

  19. Lamins: nuclear intermediate filament proteins with fundamental functions in nuclear mechanics and genome regulation.

    PubMed

    Gruenbaum, Yosef; Foisner, Roland

    2015-01-01

    Lamins are intermediate filament proteins that form a scaffold, termed nuclear lamina, at the nuclear periphery. A small fraction of lamins also localize throughout the nucleoplasm. Lamins bind to a growing number of nuclear protein complexes and are implicated in both nuclear and cytoskeletal organization, mechanical stability, chromatin organization, gene regulation, genome stability, differentiation, and tissue-specific functions. The lamin-based complexes and their specific functions also provide insights into possible disease mechanisms for human laminopathies, ranging from muscular dystrophy to accelerated aging, as observed in Hutchinson-Gilford progeria and atypical Werner syndromes.

  20. Science Skills Boot Camp Gets Interns Ready for Research | Poster

    Cancer.gov

    By Ashley DeVine, Staff Writer Summer interns learned how to read a scientific paper, present a poster, maintain a laboratory notebook, and much more, at the Science Skills Boot Camp in June. “It was a great experience, and it was a great opportunity to meet some of the other interns also working on the campus,” said Alyssa Klein, a Werner H. Kirsten student intern in the Cellular Immunology Group, Laboratory of Molecular Immunoregulation. “The boot camp covered many topics essential to being a good scientist and science researcher.”

  1. The negativity of Wigner function as a measure of quantum correlations

    NASA Astrophysics Data System (ADS)

    Siyouri, F.; El Baz, M.; Hassouni, Y.

    2016-10-01

    In this paper, we study comparatively the behaviors of Wigner function and quantum correlations for two quasi-Werner states formed with two general bipartite superposed coherent states. We show that the Wigner function can be used to detect and quantify the quantum correlations. However, we show that it is in fact not sensitive to all kinds of quantum correlations but only to entanglement. Then, we analyze the measure of non-classicality of quantum states based on the volume occupied by the negative part of the Wigner function.

  2. The 'hard problem' and the quantum physicists. Part 1: the first generation.

    PubMed

    Smith, C U M

    2006-07-01

    All four of the most important figures in the early twentieth-century development of quantum physics-Niels Bohr, Erwin Schroedinger, Werner Heisenberg and Wolfgang Pauli-had strong interests in the traditional mind-brain, or 'hard,' problem. This paper reviews their approach to this problem, showing the influence of Bohr's complementarity thesis, the significance of Schroedinger's small book, 'What is life?,' the updated Platonism of Heisenberg and, perhaps most interesting of all, the interaction of Carl Jung and Wolfgang Pauli in the latter's search for a unification of mind and matter.

  3. A quantum renaissance

    NASA Astrophysics Data System (ADS)

    Aspelmeyer, Markus; Zeilinger, Anton

    2008-07-01

    Pure curiosity has been the driving force behind many groundbreaking experiments in physics. This is no better illustrated than in quantum mechanics, initially the physics of the extremely small. Since its beginnings in the 1920s and 1930s, researchers have wanted to observe the counterintuitive properties of quantum mechanics directly in the laboratory. However, because experimental technology was not sufficiently developed at the time, people like Niels Bohr, Albert Einstein, Werner Heisenberg and Erwin Schrödinger relied instead on "gedankenexperiments" (thought experiments) to investigate the quantum physics of individual particles, mainly electrons and photons.

  4. In the name of science: don't tamper with the deceptive truth...

    PubMed

    Reis, Helton J; Mukhamedyarov, Marat A; Rizvanov, Albert A; Palotás, András

    2009-12-01

    Werner Heisenberg (1901-1976) is one of the most controversial, most ambivalent and most important figures in the history of modern science. The debate surrounding him with respect to nuclear weapons and National Socialism appears unending. Even though Heisenberg's uncertainty principle of the quantum system and his involvement in the Nazi atomic bomb project have been thoroughly discussed in various journals over the past decades, no communication has ever been published at a holistic level of his greatest Nobel-prize winning achievement in theoretical physics. In order to fill up this hole, this piece explicitly communicates the Heisenberg's paradox at all levels of science.

  5. Sessions on history of space and geophysics spark interest

    NASA Astrophysics Data System (ADS)

    Schröder, Wilfried

    Three sessions at international conferences were held in 1997 to discuss the history of space and geophysics and its different disciplines. The first session was held during the Assembly of the German Geophysical Society in March in Potsdam, Germany. Topics included the theory of relativity and gravitation in geophysics; work by Albert Abraham Michelson, Leon Foucault, and Ernst Mach; work by Hermann von Helmholtz; and the physical application and geophysical evidence of Werner Heisenberg's research. Also included were discussions relevant to the history of geophysics, aeronomy, meteor astronomy, and geodetical research, including developments in instrumentation during the last few decades.

  6. Student Intern Freed Competes at Intel ISEF, Two Others Awarded at Local Science Fair | Poster

    Cancer.gov

    Class of 2014–2015 Werner H. Kirsten (WHK) student intern Rebecca “Natasha” Freed earned a fourth-place award in biochemistry at the 2015 Intel International Science and Engineering Fair (ISEF), the largest high school science research competition in the world, according to the Society for Science & the Public’s website. Freed described the event as “transformative experience,” where she was able to present her research to “experts, including Nobel laureates, as well as members of the general community and, of course, to [other students].”

  7. Decoherence of Two-qubits Coupled with Reservoirs Studied with New Ket-Bra Entangled State Method

    NASA Astrophysics Data System (ADS)

    Ren, Yi-Chong; Fan, Hong-Yi

    2016-04-01

    For the first time we define a so-called Ket-Bra Entangled State (KBES) for two-qubits coupled with reservoirs by introduce an extra fictitious mode vector, and convert the corresponding master equation into Schrödinger-like equation by virtue of this state. Via this approach we concisely obtain the dynamic evolution of two uncoupled qubits each immersed in local thermal noise. Based on this, the decoherence evolution for the extended Werner-like states is derived and how purity and temperature influence the concurrence is analyzed. This KBES method may also be applied to tackling master equations of limited atomic level systems.

  8. Non-Markovian dynamics of multipartite open quantum systems with internal interactions

    NASA Astrophysics Data System (ADS)

    Liu, Boyang; Dai, Hong-Yi; Chen, Xi; Zhang, Ming

    2015-04-01

    How internal interactions influence the state dynamics of multipartite open quantum systems is investigated with a typical model, where two interacting qubits are coupled with a non-Markovian vacuum field environment. A general state dynamical equation containing all the internal interactions is derived and its analytical solution is presented for the system initially in an extended Werner-like state and coupled with a Lorentzian field. With a discussion of concurrence evolutions in various systems, our research indicates that the entanglement could be significantly affected by internal interactions and omitting them imprudently would lead to errors in estimating features of the system.

  9. Saving entangled photons from sudden death is a single-mode fiber --- Interplay of Decoherence and dynamical decoupling

    NASA Astrophysics Data System (ADS)

    Gupta, Manish Kumar; You, Chenglong; Dowling, Jonathan P.; Lee, Hwang

    2016-05-01

    We study the dynamics of decoherence in an optical fiber for the case of entangled photons. Such a study will allow us to increase the physical length of fiber for transmission of entangled photon from the sources such as SPDC. We analytically derive the model for Decoherence of entangled state photons in a single-mode fiber. We also show that entanglement lifetime can be increased for Bell state and Werner state with open loop control technique called Dynamical decoupling. The authors would like to acknowledge support from the Air Force Office of Scientific Research, the Army Research Office, the National Science Foundation and the Northrop Grumman Corporation.

  10. ATOMIC AND MOLECULAR PHYSICS: Quantum stereodynamics study for the reaction F + HD

    NASA Astrophysics Data System (ADS)

    Liu, Yu-Fang; Zhang, Wei; Shi, De-Heng; Sun, Jin-Feng

    2009-10-01

    This paper studies the quantum stereodynamics of the F + HD(ν = 0,j = 0) → HD + F/HF + D reaction at the collision energies of 0.52 and 0.87 kcal/mol. The quantum scattering calculations, based on Stark-Werner potential energy surfaces, show that the differential cross sections for the HF(ν' = 2) + D and DF(ν' = 3) + H channels are consistent with the recent theoretical results. Furthermore, the product rotational angular momentum orientation and alignment have been determined for some selected rovibrational states of the HF + D and DF + H channels.

  11. [Fibronectin, aging and related pathologies].

    PubMed

    Labat-Robert, J; Chevalier, X

    1991-01-01

    It could be demonstrated that plasma and tissue fibronectin (FN) increase with age. Some age dependent diseases as diabetes, osteoarthritis and Werner syndrome produce also an increase of tissue fibronectin biosynthesis. Plasma fibronectin decreases in diabetes and in breast cancer. Alternative splicing of the FN gene appears also to vary with age and in some related pathologies. Nutritional status and UV light also influence FN biosynthesis. It appears therefore that the determination of plasma FN and its isoforms as well as the study of tissue FN may be of interest for the study of chronological aging and related pathologies. PMID:1835421

  12. Light deflection with torsion effects caused by a spinning cosmic string

    NASA Astrophysics Data System (ADS)

    Jusufi, Kimet

    2016-06-01

    Using a new geometrical method introduced by Werner, we find the deflection angle in the weak limit approximation by a spinning cosmic string in the context of the Einstein-Cartan (EC) theory of gravity. We begin by adopting the String-Randers optical metric, then we apply the Gauss-Bonnet theorem to the optical geometry and derive the leading terms of the deflection angle in the equatorial plane. Calculation shows that light deflection is affected by the intrinsic spin of the cosmic string and torsion.

  13. Former WHK Intern Returns to NCI at Frederick as Earl-Stadtman Investigator | Poster

    Cancer.gov

    The Laboratory of Cell and Developmental Signaling (LCDS) recently welcomed John Brognard, Ph.D., as the new Earl-Stadtman Investigator. While Brognard is new to this role, he is not new to NCI at Frederick. In high school, Brognard was a Werner H. Kirsten Student Intern in what was formerly known as the ABL research program, where he worked under Bob Moschel, Ph.D., senior investigator, and Gary Pauly, Ph.D., currently a staff scientist in the Chemical Biology Laboratory.

  14. "...Rewritten in the skin": clues to skin biology and aging from inherited disease.

    PubMed

    Monnat, Raymond J

    2015-06-01

    The growing diversity of heritable skin diseases, a practical challenge to clinicians and dermato-nosologists alike, has nonetheless served as a rich source of insight into skin biology and disease mechanisms. I summarize below some key insights from the recent gene-driven phase of research on Werner syndrome, a heritable adult progeroid syndrome with prominent dermatologic features, constitutional genomic instability, and an elevated risk of cancer. I also indicate how new insights into skin biology, disease, and aging may come from unexpected sources.

  15. Look Forward to Take a Hike Day This Spring | Poster

    Cancer.gov

    Are you looking forward to spring? Join Occupational Health Services (OHS) and the R&W Club Frederick for the next Take a Hike Day in April. At the fall event, about 30 employees walked or jogged the 1.3-mile course around the NCI at Frederick campus during their lunch hours. The event is designed to encourage employees to engage in physical activity, according to Sarah Hooper, manager of OHS. “It was so wonderful to see employees walking to wellness,” said Emily Burnett, a Werner H. Kirsten student intern in OHS who helped plan the fall event.

  16. Ökophysik: Plaudereien über das Leben auf dem Land, im Wasser und in der Luft

    NASA Astrophysics Data System (ADS)

    Nachtigall, W.

    Prof. em. Dr. rer. nat. Werner Nachtigall, geb. 1934, war als Zoophysiologe und Biophysiker Leiter des Zoologischen Instituts der Universität des Saarlandes in Saarbrücken. In Forschung und Ausbildung hat er sich insbesondere mit Aspekten der Technischen Biologie und Bionik befasst und mit seinen Forschergruppen viele Basisdaten insbesondere zur Ökologie, Physiologie und Physik des Fliegens und Schwimmens aber auch zur Stabilität beispielsweise der Gräser erarbeitet. Lebewesen überraschen immer wieder durch ihre "Biodiversität", ihre hochspezifischen Ausgestaltungen und Anpassungen.

  17. [Blister dermatitis caused by Epicauta flagellaria (Erichson) (Coleoptera: Meloidae) species].

    PubMed

    Méndez, E; Sáenz, R E; Johnson, C M

    1989-09-01

    This paper is the first published report of vesicular dermatitis due to blister beetles of the family Meloidae in Panamá. A familial outbreak of bullous dermatitis caused by Epicauta flagellaria (Erichson) is described. All previous cases known in the Gorgas Memorial Laboratory were associated with E. isthmica Werner. Bullous lesions are produced when cantharidin, a vesicating toxin contained in the beetle's body, is released at the time the insect is crushed or rubbed upon the exposed skin. Rules for the treatment and prevention of this disease are indicated. PMID:2813877

  18. Discovery of a new PG 1159 (GW Vir) pulsator

    NASA Astrophysics Data System (ADS)

    Kepler, S. O.; Fraga, Luciano; Winget, Don Earl; Bell, Keaton; Córsico, Alejandro H.; Werner, Klaus

    2014-08-01

    We report the discovery of pulsations in the spectroscopic PG 1159 type pre-white dwarf SDSS J075415.12 + 085232.18. Analysis of the spectrum by Werner et al. indicated Teff = 120 000 ± 10 000 K, log g = 7.0 ± 0.3, mass {M}=0.52 ± 0.02 M_{⊙}, C/He = 0.33 by number. We obtained time series images with the SOAR 4.1 m telescope and 2.1 m Otto Struve telescope at McDonald Observatory and show the star is also a variable PG 1159 type star, with dominant period of 525 s.

  19. In the name of science: don't tamper with the deceptive truth...

    PubMed

    Reis, Helton J; Mukhamedyarov, Marat A; Rizvanov, Albert A; Palotás, András

    2009-12-01

    Werner Heisenberg (1901-1976) is one of the most controversial, most ambivalent and most important figures in the history of modern science. The debate surrounding him with respect to nuclear weapons and National Socialism appears unending. Even though Heisenberg's uncertainty principle of the quantum system and his involvement in the Nazi atomic bomb project have been thoroughly discussed in various journals over the past decades, no communication has ever been published at a holistic level of his greatest Nobel-prize winning achievement in theoretical physics. In order to fill up this hole, this piece explicitly communicates the Heisenberg's paradox at all levels of science. PMID:20105124

  20. Three Dimensional Periodic Table of the Elements `Elementouch'

    NASA Astrophysics Data System (ADS)

    Maeno, Yoshiteru

    2010-03-01

    A three-dimensional periodic table of the elements `Elementouch', useful in a wide variety of occasions of science education, is introduced. The element names are continuously arranged on three circular surfaces representing the electron orbits of an atom. In this way, the properties of each element in its typical ionic state can be seen more clearly than in the widely-used long period table, introduced in 1905 by Alfred Werner. The Elementouch can be readily made using the patterns downloaded from the following URL: http://www.ss.scphys.kyoto-u.ac.jp/elementouch/index-e.html .

  1. Dynamic Confinement of ITER Plasma by O-Mode Driver at Electron Cyclotron Frequency Range

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2009-05-01

    A low B-field side launched electron cyclotron O-Mode driver leads to the dynamic rf confinement, in addition to rf turbulent heating, of ITER plasma. The scaling law for the local energy confinement time τE is evaluated (τE ˜ 3neTe/2Q, where (3/2) neTe is the local plasma thermal energy density and Q is the local rf turbulent heating rate). The dynamics of unstable dissipative trapped particle modes (DTPM) strongly coupled to Trivelpiece-Gould (T-G) modes is studied for gyrotron frequency 170GHz; power˜24 MW CW; and on-axis B-field ˜ 10T. In the case of dynamic stabilization of DTPM turbulence and for the heavily damped T-G modes, the energy confinement time scales as τE˜(I0)-2, whereby I0(W/m^2) is the O-Mode driver irradiance. R. Prater et. al., Nucl. Fusion 48, No 3 (March 2008). E. P. Velikhov, History of the Russian Tokamak and the Tokamak Thermonuclear Fusion Research Worldwide That Led to ITER (Documentary movie; Stefan Studios Int'l, La Jolla, CA, 2008; E. P. Velikhov, V. Stefan.) M N Rosenbluth, Phys. Scr. T2A 104-109 1982 B. B. Kadomtsev and O. P. Pogutse, Nucl. Fusion 11, 67 (1971).

  2. Vapor Transport Within the Thermal Diffusion Cloud Chamber

    NASA Technical Reports Server (NTRS)

    Ferguson, Frank T.; Heist, Richard H.; Nuth, Joseph A., III

    2000-01-01

    A review of the equations used to determine the 1-D vapor transport in the thermal diffusion cloud chamber (TDCC) is presented. These equations closely follow those of the classical Stefan tube problem in which there is transport of a volatile species through a noncondensible, carrier gas. In both cases, the very plausible assumption is made that the background gas is stagnant. Unfortunately, this assumption results in a convective flux which is inconsistent with the momentum and continuity equations for both systems. The approximation permits derivation of an analytical solution for the concentration profile in the Stefan tube, but there is no computational advantage in the case of the TDCC. Furthermore, the degree of supersaturation is a sensitive function of the concentration profile in the TD CC and the stagnant background gas approximation can make a dramatic difference in the calculated supersaturation. In this work, the equations typically used with a TDCC are compared with very general transport equations describing the 1-D diffusion of the volatile species. Whereas no pressure dependence is predicted with the typical equations, a strong pressure dependence is present with the more general equations given in this work. The predicted behavior is consistent with observations in diffusion cloud experiments. It appears that the new equations may account for much of the pressure dependence noted in TDCC experiments, but a comparison between the new equations and previously obtained experimental data are needed for verification.

  3. Entropy density of an adiabatic relativistic Bose-Einstein condensate star

    SciTech Connect

    Khaidir, Ahmad Firdaus; Kassim, Hasan Abu; Yusof, Norhasliza

    2015-04-24

    Inspired by recent works, we investigate how the thermodynamics parameters (entropy, temperature, number density, energy density, etc) of Bose-Einstein Condensate star scale with the structure of the star. Below the critical temperature in which the condensation starts to occur, we study how the entropy behaves with varying temperature till it reaches its own stability against gravitational collapse and singularity. Compared to photon gases (pressure is described by radiation) where the chemical potential, μ is zero, entropy of photon gases obeys the Stefan-Boltzmann Law for a small values of T while forming a spiral structure for a large values of T due to general relativity. The entropy density of Bose-Einstein Condensate is obtained following the similar sequence but limited under critical temperature condition. We adopt the scalar field equation of state in Thomas-Fermi limit to study the characteristics of relativistic Bose-Einstein condensate under varying temperature and entropy. Finally, we obtain the entropy density proportional to (σT{sup 3}-3T) which obeys the Stefan-Boltzmann Law in ultra-relativistic condition.

  4. Final report on LDRD project: A phenomenological model for multicomponent transport with simultaneous electrochemical reactions in concentrated solutions

    SciTech Connect

    CHEN,KEN S.; EVANS,GREGORY H.; LARSON,RICHARD S.; NOBLE,DAVID R.; HOUF,WILLIAM G.

    2000-01-01

    A phenomenological model was developed for multicomponent transport of charged species with simultaneous electrochemical reactions in concentrated solutions, and was applied to model processes in a thermal battery cell. A new general framework was formulated and implemented in GOMA (a multidimensional, multiphysics, finite-element computer code developed and being enhanced at Sandia) for modeling multidimensional, multicomponent transport of neutral and charged species in concentrated solutions. The new framework utilizes the Stefan-Maxwell equations that describe multicomponent diffusion of interacting species using composition-insensitive binary diffusion coefficients. The new GOMA capability for modeling multicomponent transport of neutral species was verified and validated using the model problem of ternary gaseous diffusion in a Stefan tube. The new GOMA-based thermal battery computer model was verified using an idealized battery cell in which concentration gradients are absent; the full model was verified by comparing with that of Bernardi and Newman (1987) and validated using limited thermal battery discharge-performance data from the open literature (Dunning 1981) and from Sandia (Guidotti 1996). Moreover, a new Liquid Chemkin Software Package was developed, which allows the user to handle manly aspects of liquid-phase kinetics, thermodynamics, and transport (particularly in terms of computing properties). Lastly, a Lattice-Boltzmann-based capability was developed for modeling pore- or micro-scale phenomena involving convection, diffusion, and simplified chemistry; this capability was demonstrated by modeling phenomena in the cathode region of a thermal battery cell.

  5. Optimal Control of Thermo--Fluid Phenomena in Variable Domains

    NASA Astrophysics Data System (ADS)

    Volkov, Oleg; Protas, Bartosz

    2008-11-01

    This presentation concerns our continued research on adjoint--based optimization of viscous incompressible flows (the Navier--Stokes problem) coupled with heat conduction involving change of phase (the Stefan problem), and occurring in domains with variable boundaries. This problem is motivated by optimization of advanced welding techniques used in automotive manufacturing, where the goal is to determine an optimal heat input, so as to obtain a desired shape of the weld pool surface upon solidification. We argue that computation of sensitivities (gradients) in such free--boundary problems requires the use of the shape--differential calculus as a key ingredient. We also show that, with such tools available, the computational solution of the direct and inverse (optimization) problems can in fact be achieved in a similar manner and in a comparable computational time. Our presentation will address certain mathematical and computational aspects of the method. As an illustration we will consider the two--phase Stefan problem with contact point singularities where our approach allows us to obtain a thermodynamically consistent solution.

  6. A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting.

    SciTech Connect

    Dr. Zabaras, N.; Tan, L.

    2005-07-12

    A method combining features of front-tracking methods and fixed-domain methods is presented to model dendritic solidification of pure materials. To explicitly track the interface growth and shape of the solidifying crystals, a fronttracking approach based on the level set method is implemented. To easily model the heat and momentum transport, a fixed-domain method is implemented assuming a diffused freezing front where the liquid fraction is defined in terms of the level set function. The fixed-domain approach, by avoiding the explicit application of essential boundary conditions on the freezing front, leads to an energy conserving methodology that is not sensitive to the mesh size. To compute the freezing front morphology, an extended Stefan condition is considered. Applications to several classical Stefan problems and two- and three-dimensional crystal growth of pure materials in an undercooled melt including the effects of melt flow are considered. The computed results agree very well with available analytical solutions as well as with results obtained using front-tracking techniques and the phase-field method.

  7. The impact of pressure and temperature on growth rate and layer uniformity in the sublimation growth of AlN crystals

    NASA Astrophysics Data System (ADS)

    Gao, B.; Nakano, S.; Kakimoto, K.

    2012-01-01

    To effectively design a large furnace for producing large-size AlN crystals, a fully coupled compressible flow solver was developed to study the sublimation and mass transport processes in AlN crystal growth. Compressible effect, buoyancy effects, flow coupling between aluminum gas and nitrogen gas, and Stefan effect are included. Two sets of experimental data were used to validate the present solver. Simulation results showed that the distributions of Al and N 2 partial pressures are opposite along the axial direction due to constant total pressure and Stefan effect, with the Al and nitrogen partial pressures being highest at the source and seed crystals positions, respectively. The distributions of species inside the growth chamber are obviously two-dimensional, which can curve a flat crystal surface. Simulation results also showed that AlN crystal growth rate can be increased by reducing total pressure or by increasing seed temperature or by increasing source-seed temperature difference. High nitrogen pressure causes decrease in growth rate, but it is beneficial for obtaining uniform growth rate in the radial direction. Results of simulation also showed that there is an optimized temperature difference (40 °C) in the present furnace for obtaining good homogeneity of growth rate.

  8. AURORA: The Next Generation Space Weather Sensor for NPOESS

    NASA Astrophysics Data System (ADS)

    Paxton, L.; Morrison, D.; Santo, A.; Ogorzalek, B.; Goldsten, J.; Boldt, J.; Kil, H.; Zhang, Y.; Demajistre, R.; Wolven, B.; Meng, C.

    2005-12-01

    The AURORA sensor slated for flight on the NPOESS satellites represents the culmination of over 20 years of experience at JHU/APL in the design, manufacture, flight, operation and analysis of compact, cost-effective far ultraviolet sensors for space weather data collection. The far ultraviolet covers the spectral range from about 115 to 185 nm. This region is ideal for observations of the upper atmosphere because, at these wavelengths, the lower atmosphere and Earth's surface are black. AURORA will observe the mid- and low-latitude F-region ionosphere, the auroral E-region ionosphere, the day thermosphere composition, auroral energy deposition and map ionospheric irregularities. AURORA implements the flight-proven design derived from SSUSI on the DMSP Block 5D spacecraft and GUVI on the NASA TIMED spacecraft. These instruments have provided the instrument and algorithm heritage for NPOESS/AURORA. In this talk the performance capabilities of the AURORA instrument will be summarized along with the design of the instrument and algorithms. Example products will be shown for each of the measurement regimes. We acknowldge support from DMSP and NASA and the collaboration with our science colleagues at the Aerospace Corporation (Paul Straus, Jim Hecht, Dave McKenzie, and Andy Christensen) and Computational Physics (Doug Strickland, Hal Knight, and Scott Evans) and Naval Research Laboratory (Robert Meier, Mike Picone, Stefan Thonnard, Pat Dandenault, and Andy Stefan) and our colleagues at APL (Michele Weiss, Doug Holland, Bill Wood, and Jim Eichert) among others.

  9. Evidence of high-elevation amplification versus Arctic amplification.

    PubMed

    Wang, Qixiang; Fan, Xiaohui; Wang, Mengben

    2016-01-01

    Elevation-dependent warming in high-elevation regions and Arctic amplification are of tremendous interest to many scientists who are engaged in studies in climate change. Here, using annual mean temperatures from 2781 global stations for the 1961-2010 period, we find that the warming for the world's high-elevation stations (>500 m above sea level) is clearly stronger than their low-elevation counterparts; and the high-elevation amplification consists of not only an altitudinal amplification but also a latitudinal amplification. The warming for the high-elevation stations is linearly proportional to the temperature lapse rates along altitudinal and latitudinal gradients, as a result of the functional shape of Stefan-Boltzmann law in both vertical and latitudinal directions. In contrast, neither altitudinal amplification nor latitudinal amplification is found within the Arctic region despite its greater warming than lower latitudes. Further analysis shows that the Arctic amplification is an integrated part of the latitudinal amplification trend for the low-elevation stations (≤500 m above sea level) across the entire low- to high-latitude Northern Hemisphere, also a result of the mathematical shape of Stefan-Boltzmann law but only in latitudinal direction. PMID:26753547

  10. Nonlinear Interaction of the Beat-Photon Beams with the Brain Neurocenters: Laser Neurophysics

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2010-03-01

    I propose a novel mechanism for laser-brain interaction: Nonlinear interaction of ultrashort pulses of beat-photon, (φ1-- φ2), or double-photon, (φ1+φ2), footnotetextMaria Goeppert-Mayer, "Uber Elementarakte mit zwei Quantenspr"ungen, Ann Phys 9, 273, 95. (1931). beams with the corrupted brain neurocenters, causing a particular neurological disease. The open-scull cerebral tissue can be irradiated with the beat-photon pulses in the range of several 100s fs, with the laser irradiances in the range of a few mW/cm^2, repetition rate of a few 100s Hz, and in the frequency range of 700-1300nm generated in the beat-wave driven free electron laser.footnotetextV. Alexander Stefan, The Interaction of Photon Beams with the DNA Molecules: Genomic Medical Physics. American Physical Society, 2009 APS March Meeting, March 16-20, 2009, abstract #K1.276; V. Stefan, B. I. Cohen, and C. Joshi, Nonlinear Mixing of Electromagnetic Waves in Plasmas Science 27 January 1989:Vol. 243. no. 4890, pp. 494 -- 500 (January 1989). This method may prove to be an effective mechanism in the treatment of neurological diseases: Parkinson's, Lou Gehrig's, and others.

  11. New Oscillatory Instability in a Mushy Layer in a Modulated Environment during the Solidification of Binary Alloys

    NASA Astrophysics Data System (ADS)

    Srimani, P. K.; Murthy, M. Vinayaka

    2011-12-01

    In this paper, the effect of gravity modulation on a new oscillatory instability in a mushy layer is discussed. During the solidification of binary mixture from a cold boundary quite often, the planar solidification front becomes unstable due to the constitutional under cooling, resulting in a mushy layer that separates completely the liquid phase from the completely solid phase. Here, the mushy layer is a reactive porous medium, whose internal structure is composed of fine—scale crystals through which the residual melt can flow. Some of the important results of the present investigation are: (i) There exists a limit for the Stefan number, which incorporates a key balance necessary for the existence of oscillatory instability under gravity modulation. (ii) The model incorporates a complex interaction of heat transfer, modulatory convection and solidification. (iii) The steady and oscillatory modes strongly depend on seven dimensionless parameters. (iv) The oscillatory instability is driven solely from the interior of the mushy layer and exists for all wave numbers. (v) A thorough discussion of the results reveals the different transition boundaries associated with the feasible combination of the parameters. (vi) The system becomes more unstable to both real and oscillatory instabilities as the Stefan number increases for a fixed of value of the modulation parameter. (vii) Modulated convection in a mushy layer could be enhanced or suppressed by a suitable choice of the governing parameters. Finally it is observed that, the results are of practical interest.

  12. Evolution of a spherical hydrate-free inclusion in a porous matrix filled with methane hydrate.

    PubMed

    Tsiberkin, Kirill; Lyubimov, Dmitry V; Lyubimova, Tatyana P; Zikanov, Oleg

    2014-02-01

    The behavior of a small isolated hydrate-free inclusion (a gas bubble) within a porous matrix filled with methane hydrate and either water or methane gas is analyzed. Simplifying assumptions of spherical symmetry, an infinite uniform porous medium, and negligible effects of background temperature and pressure variations focus the investigation on the features of the dynamics of a single bubble determined by a phase transition. Two solutions are presented: an exact solution of the Stefan problem obtained when the effects of gas and water flow are neglected, and a numerical solution of the full problem. The solutions are in good agreement with each other and with known asymptotic dependencies, confirming that the effects of inertia and convection transport can be neglected in the case of small inclusions. It is found that, after an initial adjustment, the radius of any small bubble decreases with time following a self-similar solution of the Stefan problem. The lifetime of a bubble is evaluated as a function of initial radius and the system's physical parameters. Possible effects of such inclusions on the filtration of methane to the surface and other aspects of the dynamics of hydrate-bearing deposits are discussed. PMID:25353572

  13. The Interaction of Photon Beams with the DNA Molecules: Genomic Medical Physics

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2009-03-01

    I propose a novel method for the modification of the corrupted human DNAootnotetextJ.D. Watson and F. H. C. Crick, Nature, 171, 737-738 (1953). code that causes particular genetic disease. The method is based on the nonlinear interaction between the DNA molecule and the ``modulation photons'' generated in beat wave driven free electron laser, BW-FEL.ootnotetextV. Alexander Stefan. Beat Wave Driven Free Electron Laser (S-U-Press, 2002, La Jolla, CA)[cf. V. Stefan, et al., Bull. Am. Phys. Soc. 32, No. 9, 1713 (1987)] The BW-FEL frequency is given by ν˜γ^2nφe (γ is the free electron beam relativistic factor, n is the harmonic number of the electron Bernstein plasma mode, and φe is the electron cyclotron frequency). The meV ``carrier photons'' are focused on the area of the brain, the source-center of a genetic disease. For the BW-FEL parameters: the free electron beam guiding d.c. magnetic field ˜ 1kG, γ˜10^3, and n=10, the keV ``modulation photons'' are generated, which are easily focused on the nucleotides. By modulating the frequency of the BW-FEL, the parametric resonance with the different DNA (sub-DNA) eigen molecular oscillation-modes are achieved, leading to the ``knock-on'' of the unwanted (corrupted) nucleotides.

  14. Hydrodynamic theory of diffusion in two-temperature multicomponent plasmas

    SciTech Connect

    Ramshaw, J.D.; Chang, C.H.

    1995-12-31

    Detailed numerical simulations of multicomponent plasmas require tractable expressions for species diffusion fluxes, which must be consistent with the given plasma current density J{sub q} to preserve local charge neutrality. The common situation in which J{sub q} = 0 is referred to as ambipolar diffusion. The use of formal kinetic theory in this context leads to results of formidable complexity. We derive simple tractable approximations for the diffusion fluxes in two-temperature multicomponent plasmas by means of a generalization of the hydrodynamical approach used by Maxwell, Stefan, Furry, and Williams. The resulting diffusion fluxes obey generalized Stefan-Maxwell equations that contain driving forces corresponding to ordinary, forced, pressure, and thermal diffusion. The ordinary diffusion fluxes are driven by gradients in pressure fractions rather than mole fractions. Simplifications due to the small electron mass are systematically exploited and lead to a general expression for the ambipolar electric field in the limit of infinite electrical conductivity. We present a self-consistent effective binary diffusion approximation for the diffusion fluxes. This approximation is well suited to numerical implementation and is currently in use in our LAVA computer code for simulating multicomponent thermal plasmas. Applications to date include a successful simulation of demixing effects in an argon-helium plasma jet, for which selected computational results are presented. Generalizations of the diffusion theory to finite electrical conductivity and nonzero magnetic field are currently in progress.

  15. Crystallization of glass-forming liquids: Specific surface energy

    NASA Astrophysics Data System (ADS)

    Schmelzer, Jürn W. P.; Abyzov, Alexander S.

    2016-08-01

    A generalization of the Stefan-Skapski-Turnbull relation for the melt-crystal specific interfacial energy is developed in terms of the generalized Gibbs approach extending its standard formulation to thermodynamic non-equilibrium states. With respect to crystal nucleation, this relation is required in order to determine the parameters of the critical crystal clusters being a prerequisite for the computation of the work of critical cluster formation. As one of its consequences, a relation for the dependence of the specific surface energy of critical clusters on temperature and pressure is derived applicable for small and moderate deviations from liquid-crystal macroscopic equilibrium states. Employing the Stefan-Skapski-Turnbull relation, general expressions for the size and the work of formation of critical crystal clusters are formulated. The resulting expressions are much more complex as compared to the respective relations obtained via the classical Gibbs theory. Latter relations are retained as limiting cases of these more general expressions for moderate undercoolings. By this reason, the formulated, here, general relations for the specification of the critical cluster size and the work of critical cluster formation give a key for an appropriate interpretation of a variety of crystallization phenomena occurring at large undercoolings which cannot be understood in terms of the Gibbs' classical treatment.

  16. Local hidden-variable models for entangled quantum states

    NASA Astrophysics Data System (ADS)

    Augusiak, R.; Demianowicz, M.; Acín, A.

    2014-10-01

    While entanglement and violation of Bell inequalities were initially thought to be equivalent quantum phenomena, we now have different examples of entangled states whose correlations can be described by local hidden-variable models and, therefore, do not violate any of the Bell inequalities. We provide an up-to-date overview of the existing literature regarding local hidden-variable models for entangled quantum states, in both the bipartite and multipartite cases, and discuss some of the most relevant open questions in this context. Our review covers twenty five years of this line of research, beginning with the seminal work by Werner (1989 Phys. Rev. A 40 8), which provided the first example of an entangled state with a local model. Werner's work, in turn, appeared twenty five years after the seminal work by Bell (1964 Physics 1 195), about the impossibility of recovering the predictions of quantum mechanics using a local hidden-variable theory. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘50 years of Bell’s theorem’.

  17. The historical development of modern virus research in Germany, especially in the Kaiser-Wilhelm-/Max-Planck-Society, 1936--1954.

    PubMed

    Butenandt, A

    1977-01-01

    This is lecture on the historical development of modern virus research in Germany to introduce a symposium dedicated to Prof. Werner Schäfer, Tübingen, on the occasion of his 65th birthday. The author was set the task of relating from his memories the beginning of modern virus research in Germany. This research has, since 1936, essentially taken place in the Kaiser-Wilhelm/Max-Planck-Society and in 1954 led to the founding of the Max-Planck-Institute for Virus Research in Tübingen, an institute which to the present day owes its scientific reputation in considerable part to the activity of Werner Schäfer. Since the author personally experienced and participated in the Institute's development from 1936-1954, his remarks are predominantly influenced by personal recollections, which have been sharpended by a renewed study of old records in the 'Library and Archive of the History of the Max-Planck-Gesellschaft', Berlin-Dahlem.

  18. DNA secondary structure of the released strand stimulates WRN helicase action on forked duplexes without coordinate action of WRN exonuclease

    SciTech Connect

    Ahn, Byungchan; Bohr, Vilhelm A.

    2011-08-12

    Highlights: {yields} In this study, we investigated the effect of a DNA secondary structure on the two WRN activities. {yields} We found that a DNA secondary structure of the displaced strand during unwinding stimulates WRN helicase without coordinate action of WRN exonuclease. {yields} These results imply that WRN helicase and exonuclease activities can act independently. -- Abstract: Werner syndrome (WS) is an autosomal recessive premature aging disorder characterized by aging-related phenotypes and genomic instability. WS is caused by mutations in a gene encoding a nuclear protein, Werner syndrome protein (WRN), a member of the RecQ helicase family, that interestingly possesses both helicase and exonuclease activities. Previous studies have shown that the two activities act in concert on a single substrate. We investigated the effect of a DNA secondary structure on the two WRN activities and found that a DNA secondary structure of the displaced strand during unwinding stimulates WRN helicase without coordinate action of WRN exonuclease. These results imply that WRN helicase and exonuclease activities can act independently, and we propose that the uncoordinated action may be relevant to the in vivo activity of WRN.

  19. Ultraviolet spectroscopy of the Jovian and Saturnian auroras

    NASA Technical Reports Server (NTRS)

    Durrance, S. T.; Feldman, P. D.; Moos, H. W.

    1982-01-01

    The results of a series of IUE observations of the north polar aurora obtained during a substantial fraction of one complete rotation of Jupiter are presented. From these data a spectrum of the aurora with high signal to noise ratio, and a resolution of about 8 A was obtained, making possible the identification of many H2 Lyman and Werner bands. The spectrum is of sufficient quality to provide reliable quantative data for a comparison with the model atmosphere calculations. The lack of an observable absorption signature makes it possible to set an upper limit on the column density of CH4 and C2H6 above the auroral emissions and hence an upper limit on the primary particle energies. A comparison of this spectrum with a laboratory spectrum of discharge excited H2 shows a remarkable similarity. The results of several IUE observations of the full disk of Saturn are also examined. The exposures were of approximately 2 hours each, and the H2 Lyman and Werner bands were observed near the north pole in two of them.

  20. STS-99 / Endeavour SRTM Science Briefing and Applications from JSC

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The primary objective of the STS-99 mission was to complete high resolution mapping of large sections of the Earth's surface using the Shuttle Radar Topography Mission (SRTM), a specially modified radar system. This radar system produced unrivaled 3-D images of the Earth's Surface. This videotape shows a science press briefing. The panel members are Michael Kobrick, the SRTM Project Scientist at JPL; Thomas Henning, SRTM Program Manager at the National Imagery and Mapping Agency; Diane Evans, the Director of the Earth Sciences Program at NASA; and Marian Werner, XSAR Project Manager for the DLR, Deutschen Zentrum fur Luft- und Raumfahrt, Germany's National Aerospace Research Center. Michael Kobrick explained the mechanics of interferometric measurements of the Earth. He explained and demonstrated with a scale model the deployable mast's use. He also explained the importance of the attitude and orbit determination avionics. A brief animated video showing how four beams would give a 225 km wide swath of the Earth topography was viewed. Thomas Henning discussed some of the usage of the digital terrain elevation data for flood relief planning, cell phone station placement, military planning for command and control centers, and flight simulation. He explained that public access to the most precise data would be limited. Diane Evans described data usage in flood prediction, earthquake fault identification and archeology. Marian Werner described the German and Italian input to the project. The questions from the press concerned the time to process this data, and the reasons for the limited access to the more precise data.

  1. The spectrum of the Jovian dayglow observed at 3 A resolution with the Hopkins ultraviolet telescope

    NASA Technical Reports Server (NTRS)

    Feldman, P. D.; Mcgrath, M. A.; Moos, H. W.; Durrance, S. T.; Strobel, D. F.; Davidsen, A. F.

    1993-01-01

    Ultraviolet spectra of the Jovian equatorial dayglow in the spectral range 830-1850 A were obtained at about 3 A resolution. The observed spectrum is dominated by electron impact excitation of the H2 Lyman and Werner band systems. Solar Lyman-beta induced fluorescence in the (6, nu-double prime) Lyman band progression is clearly identified in five distinct P(1) lines, and the contribution of solar fluorescence to the total 2.3 kR slit-averaged H2 emission rate is estimated to be 17-22 percent. The electron excitation spectrum is characterized by a relative weakness of the Werner band system and the absence of cascade contributions to the Lyman system and is very similar to that of the south polar aurora. The integrated H2 emission rate in the 900-1100 A band is a factor of two lower than that measured by the Voyager UVS. Based on model calculations, photoelectron excitation does not appear able to account for the amount of observed electron-excited H2 emission.

  2. WRN translocation from nucleolus to nucleoplasm is regulated by SIRT1 and required for DNA repair and the development of chemoresistance.

    PubMed

    Lee, Sun-Young; Lee, Hyunwoo; Kim, Eun-Sun; Park, Sojin; Lee, Jiyoen; Ahn, Byungchan

    2015-04-01

    When defective or absent, Werner syndrome protein (WRN) causes a genetic premature aging disorder called Werner syndrome. Several studies have reported that defects in WRN function are responsible for not only progeria syndrome but also genomic instability via the deregulation of DNA repair, replication, recombination, and telomere stability. Given the importance of WRN in the repair process, we herein investigated the potential role of WRN in drug response by evaluating the DNA repair following exposure to cisplatin in human cancer cell lines. We found that the down-regulation of SIRT1 and inhibition of SIRT1 deacetylase activity blocked the translocation of WRN from the nucleolus to the nucleoplasm in response to genotoxic stresses. In addition, cells expressing low levels of WRN responded favorably to cisplatin, whereas cells expressing high levels responded poorly to cisplatin. The forced expression of WRN protein in chemosensitive cells resulted in an approximately two-fold increase in cell viability in response to cisplatin compared with vector controls and promoted DNA repair, while WRN-deficient cells accumulate unrepaired double-strand breaks following cisplatin exposure. These results suggest that WRN is regulated by SIRT1 and increased expression of WRN might be one of the determinants for the development of chemotherapeutic drug resistance.

  3. Mechanisms of formation of chromosomal aberrations: insights from studies with DNA repair-deficient cells.

    PubMed

    Palitti, F

    2004-01-01

    In order to understand the mechanisms of formation of chromosomal aberrations, studies performed on human syndromes with genomic instability can be fruitful. In this report, the results from studies in our laboratory on the importance of the transcription-coupled repair (TCR) pathway on the induction of chromosomal damage and apoptosis by ultraviolet light (UV) are discussed. UV61 cells (hamster homologue of human Cockayne's syndrome group B) deficient in TCR showed a dramatic increase in the induction of chromosomal aberrations and apoptosis following UV treatment. At relatively low UV doses, the induction of chromosomal aberrations preceded the apoptotic process. Chromosomal aberrations probably lead to apoptosis and most of the cells had gone through an S phase after the UV treatment before entering apoptosis. At higher doses of UV, the cells could go into apoptosis already in the G1 phase of the cell cycle. Abolition of TCR by treatment with alpha-amanitin (an inhibitor of RNA polymerase II) in the parental cell line AA8 also resulted in the induction of elevated chromosomal damage and apoptotic response similar to the one observed in UV61 cells treated with UV alone. This suggests that the lack of TCR is responsible for the increased frequencies of chromosomal aberrations and apoptosis in UV61 cells. Hypersensitivity to the induction of chromosomal damage by inhibitors of antitopoisomerases I and II in Werner's syndrome cells is also discussed in relation to the compromised G2 phase processes involving the Werner protein. PMID:15162020

  4. Cooperation of DNA-PKcs and WRN helicase in the maintenance of telomeric D-loops.

    PubMed

    Kusumoto-Matsuo, Rika; Opresko, Patricia L; Ramsden, Dale; Tahara, Hidetoshi; Bohr, Vilhelm A

    2010-05-01

    Werner syndrome is an inherited human progeriod syndrome caused by mutations in the gene encoding the Werner Syndrome protein, WRN. It has both 3'-5' DNA helicase and exonuclease activities, and is suggested to have roles in many aspects of DNA metabolism, including DNA repair and telomere maintenance. The DNA-PK complex also functions in both DNA double strand break repair and telomere maintenance. Interaction between WRN and the DNA-PK complex has been reported in DNA double strand break repair, but their possible cooperation at telomeres has not been reported. This study analyzes thein vitro and in vivo interaction at the telomere between WRN and DNA-PKcs, the catalytic subunit of DNA-PK. The results show that DNA-PKcs selectively stimulates WRN helicase but not WRN exonuclease in vitro, affecting that WRN helicase unwinds and promotes the release of the full-length invading strand of a telomere D-loop model substrate. In addition, the length of telomeric G-tails decreases in DNA-PKcs knockdown cells, and this phenotype is reversed by overexpression of WRN helicase. These results suggest that WRN and DNA-PKcs may cooperatively prevent G-tail shortening in vivo.

  5. DNA damage and repair in telomeres: relation to aging.

    PubMed Central

    Kruk, P A; Rampino, N J; Bohr, V A

    1995-01-01

    We have established a method for the detection of DNA damage and its repair in human telomeres, the natural ends of chromosomes which are necessary for replication and critical for chromosomal stability. We find that ultraviolet light-induced pyrimidine dimers in telomeric DNA are repaired less efficiently than endogenous genes but more efficiently than inactive, noncoding regions. We have also measured telomeric length, telomeric DNA damage, and its repair in relation to the progression of aging. Telomeres are shorter in fibroblasts from an old donor compared to fibroblasts from a young donor, shortest in cells from a patient with the progeroid disorder Werner syndrome, and relatively long in fibroblasts from a patient with Alzheimer disease. Telomeric DNA repair efficiency is lower in cells from an old donor than in cells from a young donor, normal in Alzheimer cells, and slightly lower in Werner cells. It is possible that this decline in telomeric repair with aging is of functional significance to an age-related decline in genomic stability. Images Fig. 1 Fig. 2 PMID:7816828

  6. A revision of Apteromantis (Mantodea: Mantidae, Amelinae): a comprehensive approach to manage old taxonomic and conservation problems .

    PubMed

    Battiston, Roberto; Ortego, Joaquín; Correas, José R; Cordero, Pedro J

    2014-01-01

    The genus Apteromantis Werner, 1931 comprises two species of wingless mantids, the Iberian A. aptera (Fuente, 1894) and the North African A. bolivari (Werner, 1929). Although A. aptera and A. bolivari have been traditionally considered as separate and valid species, their external appearance is quite similar and no comprehensive taxonomic study has analyzed their morphological and genetic characteristics. This taxonomic uncertainty has important implications for conservation because A. aptera is considered an Iberian endemic and the only praying mantis protected by international laws. In this study, we apply a comprehensive approach, including quantitative morphological and molecular analyses, to shed new light on the taxonomic and conservation status of the genus Apteromantis and the putative species. We have found that the Iberian and North African specimens analyzed herein significantly differ in female head shape, male genitalia morphology and several other traits related to body size. Molecular data suggest the presence of two main lineages, with sequence divergence rates of approximately 4 %, which are within the range reported for other well defined insect species. Overall, this study supports that A. aptera and A. bolivari are valid species despite their ecological and morphological similarity and highlights the importance of comprehensive approaches to resolve old taxonomic and conservation problems. PMID:24870858

  7. Structures and Spectroscopic Properties Calculated for C_6H_7^+ and its Complexes with Ne, Ar, N_2, or CO_2

    NASA Astrophysics Data System (ADS)

    Botschwina, P.; Oswald, R.

    2012-06-01

    Explicitly correlated coupled cluster theory at the CCSD(T)-F12x (x = a, b) level in conjunction with the double-hybrid density functional B2PLYP-D has been employed in a study of the benzenium ion (C_6H_7^+) and its complexes with simple ligands (L = Ne, Ar, N_2, or CO_2). The ground-state rotational constants of C_6H_7^+ are predicted to be A_0 = 5445 MHz, B_0 = 5313 MHz, and C_0 = 2731 MHz. For the complexes with L = Ne, Ar or N_2, the energetically most favourable structure is of π-bonded type, but for the most strongly bound complex C_6H_7^+ ... CO_2 a conformer with the CO_2 ligand lying in the ring-plane of the C_6H_7^+ moiety is slightly lower in energy. T. B. Adler, G. Knizia, and H.-J. Werner, J. Chem. Phys. 127, 221106 (2007) G. Knizia, T. B. Adler, and H.-J. Werner, J. Chem. Phys. 130, 054104 (2009). T. Schwabe and S. Grimme, Phys. Chem. Chem. Phys. 9, 3397 (2007). P. Botschwina and R. Oswald, J. Phys. Chem. A 115, 13664 (2011) P. Botschwina and R. Oswald, J. Chem. Phys. submitted.

  8. Quality of economically extractable coal beds in the Gillette coal field as compared with other Tertiary coal beds in the Powder River basin, Wyoming and Montana

    USGS Publications Warehouse

    Ellis, Margaret S.

    2002-01-01

    The Powder River Basin, and specifically the Gillette coal field, contains large quantities of economically extractable coal resources. These coal resources have low total sulfur content and ash yield, and most of the resources are subbituminous in rank. A recent U.S Geological Survey study of economically extractable coal in the Gillette coal field focused on five coal beds, the Wyodak rider, Upper Wyodak, Canyon, Lower Wyodak-Werner, and Gates/Kennedy. This report compares the coal quality of these economically extractable coal beds to coal in the Wyodak-Anderson coal zone in the Powder River Basin and in the Gillette coal field (Flores and others, 1999) and other produced coal in the Gillette coal field (Glass, 2000). The Upper Wyodak, Canyon, and Lower Wyodak/Werner beds are within the Wyodak-Anderson coal zone. Compared with all coal in the Wyodak-Anderson coal zone, both throughout the Powder River Basin and just within the Gillette coal field; the thick, persistent Upper Wyodak coal bed in the Gillette coal field has higher mean gross calorific value (8,569 Btu/lb), lower mean ash yield (5.8 percent), and lower mean total sulfur content (0.46 percent).

  9. A revision of Apteromantis (Mantodea: Mantidae, Amelinae): a comprehensive approach to manage old taxonomic and conservation problems .

    PubMed

    Battiston, Roberto; Ortego, Joaquín; Correas, José R; Cordero, Pedro J

    2014-05-21

    The genus Apteromantis Werner, 1931 comprises two species of wingless mantids, the Iberian A. aptera (Fuente, 1894) and the North African A. bolivari (Werner, 1929). Although A. aptera and A. bolivari have been traditionally considered as separate and valid species, their external appearance is quite similar and no comprehensive taxonomic study has analyzed their morphological and genetic characteristics. This taxonomic uncertainty has important implications for conservation because A. aptera is considered an Iberian endemic and the only praying mantis protected by international laws. In this study, we apply a comprehensive approach, including quantitative morphological and molecular analyses, to shed new light on the taxonomic and conservation status of the genus Apteromantis and the putative species. We have found that the Iberian and North African specimens analyzed herein significantly differ in female head shape, male genitalia morphology and several other traits related to body size. Molecular data suggest the presence of two main lineages, with sequence divergence rates of approximately 4 %, which are within the range reported for other well defined insect species. Overall, this study supports that A. aptera and A. bolivari are valid species despite their ecological and morphological similarity and highlights the importance of comprehensive approaches to resolve old taxonomic and conservation problems.

  10. On the estimation of heating effects in the atmosphere because of seismic activities

    NASA Astrophysics Data System (ADS)

    Meister, Claudia-Veronika; Hoffmann, Dieter H. H.

    2014-05-01

    The dielectric model for waves in the Earth's ionosphere is further developed and applied to possible electro-magnetic phenomena in seismic regions. In doing so, in comparison to the well-known dielectric wave model by R.O. Dendy [Plasma dynamics, Oxford University Press, 1990] for homogeneous systems, the stratification of the atmosphere is taken into account. Moreover, within the frame of many-fluid magnetohydrodynamics also the momentum transfer between the charged and neutral particles is considered. Discussed are the excitation of Alfvén and magnetoacoustic waves, but also their variations by the neutral gas winds. Further, also other current driven waves like Farley-Buneman ones are studied. In the work, models of the altitudinal scales of the plasma parameters and the electromagnetic wave field are derived. In case of the electric wave field, a method is given to calculate the altitudinal scale based on the Poisson equation for the electric field and the magnetohydrodynamic description of the particles. Further, expressions are derived to estimate density, pressure, and temperatur changes in the E-layer because of the generation of the electromagnetic waves. Last not least, formulas are obtained to determine the dispersion and polarisation of the excited electromagnetic waves. These are applied to find quantitative results for the turbulent heating of the ionospheric E-layer. Concerning the calculation of the dispersion relation, in comparison to a former work by Meister et al. [Contr. Plasma Phys. 53 (4-5), 406-413, 2013], where a numerical double-iteration method was suggested to obtain results for the wave dispersion relations, now further analytical calculations are performed. In doing so, different polynomial dependencies of the wave frequencies from the wave vectors are treated. This helped to restrict the numerical calculations to only one iteration process.

  11. [The concept of soul in the course of history. Thoughts on psyche, mind and awareness].

    PubMed

    Hinterhuber, Hartmann

    2002-10-31

    This paper seeks to convey an insight into the interrelationships between body, soul and mind and to show how the concept of "soul" has evolved through the course of history. In German the word "soul" has a confusing array of meanings today. For most of us it comprises all of man's emotions, his awareness, constructive thought, drive, state of mind and spirit. The soul thus represents the essence of a person and his relationships to those closest to him. For many people the soul was and still is the principle of life, the breath of life and the force of life. The immortal soul escapes, leaves the body, is weighed and judged. At all times in history man has doggedly pursued the mysteries of self-awareness, the ultimate truth and the soul. What he found varied, depending on the age and the place. What the Hebrew Bible and the New Testament express in deep-seated metaphors, the Greek philosophers put into clear-cut words: their concept of soul was then largely integrated into Christian thought. Meister Eckhart describes the soul in mystically transfigured passion. C.G. Jung writes of the "animus and anima." Sigmund Freud uses the term "psyche." Radical materialism denies the existence and independence of the soul's processes. The questions where we come from and where we are going, why and what for, no longer find a common answer. Psychiatry, however, takes up the intellectual call of the time and replies to the challenges of the day. Thus, the search for the "soul", a search that occupies so many people, also always involves the search for the whole person.

  12. Enhancing radiative energy transfer through thermal extraction

    NASA Astrophysics Data System (ADS)

    Tan, Yixuan; Liu, Baoan; Shen, Sheng; Yu, Zongfu

    2016-06-01

    Thermal radiation plays an increasingly important role in many emerging energy technologies, such as thermophotovoltaics, passive radiative cooling and wearable cooling clothes [1]. One of the fundamental constraints in thermal radiation is the Stefan-Boltzmann law, which limits the maximum power of far-field radiation to P0 = σT4S, where σ is the Boltzmann constant, S and T are the area and the temperature of the emitter, respectively (Fig. 1a). In order to overcome this limit, it has been shown that near-field radiations could have an energy density that is orders of magnitude greater than the Stefan-Boltzmann law [2-7]. Unfortunately, such near-field radiation transfer is spatially confined and cannot carry radiative heat to the far field. Recently, a new concept of thermal extraction was proposed [8] to enhance far-field thermal emission, which, conceptually, operates on a principle similar to oil immersion lenses and light extraction in light-emitting diodes using solid immersion lens to increase light output [62].Thermal extraction allows a blackbody to radiate more energy to the far field than the apparent limit of the Stefan-Boltzmann law without breaking the second law of thermodynamics. Thermal extraction works by using a specially designed thermal extractor to convert and guide the near-field energy to the far field, as shown in Fig. 1b. The same blackbody as shown in Fig. 1a is placed closely below the thermal extractor with a spacing smaller than the thermal wavelength. The near-field coupling transfers radiative energy with a density greater than σT4. The thermal extractor, made from transparent and high-index or structured materials, does not emit or absorb any radiation. It transforms the near-field energy and sends it toward the far field. As a result, the total amount of far-field radiative heat dissipated by the same blackbody is greatly enhanced above SσT4, where S is the area of the emitter. This paper will review the progress in thermal

  13. Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis

    NASA Astrophysics Data System (ADS)

    Harp, D. R.; Atchley, A. L.; Painter, S. L.; Coon, E. T.; Wilson, C. J.; Romanovsky, V. E.; Rowland, J. C.

    2016-02-01

    The effects of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The null-space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of predictive uncertainty (due to soil property (parametric) uncertainty) and the inter-annual climate variability due to year to year differences in CESM climate forcings. After calibrating to measured borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant predictive uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Inter-annual climate variability in projected soil moisture content and Stefan number are small. A volume- and time-integrated Stefan number decreases significantly, indicating a shift in subsurface energy utilization in the future climate (latent heat of phase change becomes more important than heat conduction). Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we quantify the relative magnitude of soil

  14. PREFACE: 6th International Workshop on Multi-Rate Processes and Hysteresis (MURPHYS2012)

    NASA Astrophysics Data System (ADS)

    Dimian, Mihai; Rachinskii, Dmitrii

    2015-02-01

    The International Workshop on Multi-Rate Processes and Hysteresis (MURPHYS) conference series focuses on multiple scale systems, singular perturbation problems, phase transitions and hysteresis phenomena occurring in physical, biological, chemical, economical, engineering and information systems. The 6th edition was hosted by Stefan cel Mare University in the city of Suceava located in the beautiful multicultural land of Bukovina, Romania, from May 21 to 24, 2012. This continued the series of biennial multidisciplinary conferences organized in Cork, Ireland from 2002 to 2008 and in Pécs, Hungary in 2010. The MURPHYS 2012 Workshop brought together more than 50 researchers in hysteresis and multi-scale phenomena from the United State of America, the United Kingdom, France, Germany, Italy, Ireland, Czech Republic, Hungary, Greece, Ukraine, and Romania. Participants shared and discussed new developments of analytical techniques and numerical methods along with a variety of their applications in various areas, including material sciences, electrical and electronics engineering, mechanical engineering and civil structures, biological and eco-systems, economics and finance. The Workshop was sponsored by the European Social Fund through Sectoral Operational Program Human Resources 2007-2013 (PRO-DOCT) and Stefan cel Mare University, Suceava. The Organizing Committee was co-chaired by Mihai Dimian from Stefan cel Mare University, Suceava (Romania), Amalia Ivanyi from the University of Pecs (Hungary), and Dmitrii Rachinskii from the University College Cork (Ireland). All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing. The Guest Editors wish to place on record their sincere gratitude to Miss Sarah Toms for the assistance she provided

  15. Plethodon cinerius (eastern red-backed salamander) movement

    USGS Publications Warehouse

    Sterrett, Sean; Brand, Adrianne; Fields, William R.; Katz, Rachel A.; Grant, Evan H. Campbell

    2015-01-01

    Lungless salamanders (family Plethodontidae) are relatively sedentary and are presumed to have limited dispersal ability (Marsh et al. 2004. Ecology 85:3396–3405). Site fidelity in Plethodontidae is high, and individuals displaced 90 m return to home territories (Kleeberger and Werner 1982. Copeia 1982:409–415). Individuals defend territories (Jaeger et al. 1982. Anim. Behav. 30:490–496) and female home ranges have been estimated to be 24.34 m2 (Kleeberger and Werner 1982, op. cit.). Females may seek out suitable subsurface habitat to oviposit eggs, yet little is known about their maximum movement distances (Petranka 1998. Salamanders of the United States and Canada. Smithsonian Institution Press, Washington. 587 pp.).On 18 September 2014, a female P. cinereus (lead back morphotype; SVL = 44.68 mm; 0.89 g) was found under a coverboard during a standard sampling event and uniquely marked using visual implant elastomer at the S.O. Conte Anadromous Fish Research Center, Massachusetts, USA (42.59280°N, 72.58070°W, datum WGS84; elev. 74 m). This individual was subsequently recaptured at ~1500 h on 8 October 2014 under a coverboard within 3 m of the original capture location and then again ~1430 h on 16 October 2014 under a log, within the same forest patch, though in a 50 x 150 m area adjacent to the original study area. Because we found the marked salamander while collecting multiple individuals for a laboratory study, the exact recapture location of the marked individual is not known. However, the distance between the 8 October capture location and the nearest edge of the 16 October search area (i.e. 50 x 150 m) was 143 m, indicating a minimum movement distance. As far as we are aware, this is the longest recorded movement for P. cinereus by more than 53 m (Kleeberger and Werner 1982, op. cit.). This finding followed a rain event of 1.63 cm within 24 h and the second largest sustained rain event during October. The movement we observed may have been due to

  16. Heat transfer in completely and partially filled spherical phase change thermal energy storage modules

    NASA Astrophysics Data System (ADS)

    Rahman, Muhammad Mustafizur

    2016-07-01

    A comprehensive investigation of heat transfer and induced fluid flow interactions during melting in a confined storage medium is reported in this paper. This study focuses on thermal characterization of a single constituent storage module rather than an entire storage system to precisely capture the energy exchange contributions of all fundamental heat transfer mechanisms during phase change process. Two-dimensional, axisymmetric, transient equations for mass, momentum and energy conservation were solved numerically by the finite volume scheme. Results report the influence of the Grashof, Stefan and Prandtl numbers on the melting dynamics of capsules with various diameters (20, 30, 40, and 50 mm). Also the effects of the shell material have been analyzed. Correlating equations for melt fraction and Nusselt number have been developed for possible general design applications.

  17. Experimental power density distribution benchmark in the TRIGA Mark II reactor

    SciTech Connect

    Snoj, L.; Stancar, Z.; Radulovic, V.; Podvratnik, M.; Zerovnik, G.; Trkov, A.; Barbot, L.; Domergue, C.; Destouches, C.

    2012-07-01

    In order to improve the power calibration process and to benchmark the existing computational model of the TRIGA Mark II reactor at the Josef Stefan Inst. (JSI), a bilateral project was started as part of the agreement between the French Commissariat a l'energie atomique et aux energies alternatives (CEA) and the Ministry of higher education, science and technology of Slovenia. One of the objectives of the project was to analyze and improve the power calibration process of the JSI TRIGA reactor (procedural improvement and uncertainty reduction) by using absolutely calibrated CEA fission chambers (FCs). This is one of the few available power density distribution benchmarks for testing not only the fission rate distribution but also the absolute values of the fission rates. Our preliminary calculations indicate that the total experimental uncertainty of the measured reaction rate is sufficiently low that the experiments could be considered as benchmark experiments. (authors)

  18. Numerical identification of boundary conditions on nonlinearly radiating inverse heat conduction problems

    NASA Technical Reports Server (NTRS)

    Murio, Diego A.

    1991-01-01

    An explicit and unconditionally stable finite difference method for the solution of the transient inverse heat conduction problem in a semi-infinite or finite slab mediums subject to nonlinear radiation boundary conditions is presented. After measuring two interior temperature histories, the mollification method is used to determine the surface transient heat source if the energy radiation law is known. Alternatively, if the active surface is heated by a source at a rate proportional to a given function, the nonlinear surface radiation law is then recovered as a function of the interface temperature when the problem is feasible. Two typical examples corresponding to Newton cooling law and Stefan-Boltzmann radiation law respectively are illustrated. In all cases, the method predicts the surface conditions with an accuracy suitable for many practical purposes.

  19. Effects of anisotropic heat conduction on solidification

    NASA Technical Reports Server (NTRS)

    Weaver, J. A.; Viskanta, R.

    1989-01-01

    Two-dimensional solidification influenced by anisotropic heat conduction has been considered. The interfacial energy balance was derived to account for the heat transfer in one direction (x or y) depending on the temperature gradient in both the x and y directions. A parametric study was made to determine the effects of the Stefan number, aspect ratio, initial superheat, and thermal conductivity ratios on the solidification rate. Because of the imposed boundary conditions, the interface became skewed and sometimes was not a straight line between the interface position at the upper and lower adiabatic walls (spatially nonlinear along the height). This skewness depends on the thermal conductivity ratio k(yy)/k(yx). The nonlinearity of the interface is influenced by the solidification rate, aspect ratio, and k(yy/k(yx).

  20. The pressure drop in a porous material layer during combustion

    SciTech Connect

    Kondrikov, B.N.

    1995-07-01

    During the combustion of a porous material layer, a manometer, which is attached to the cold end of the charge, records at the bottom of the layer a pressure reduction, which was discovered more than 20 years ago but which remains essentially unexplained up to the present. It is experimentally shown that this effect is similar to the pressure change in the cavities when a light gas (helium, hydrogen) diffuses from (or to) them under isothermal conditions and that it increases during the combustion mainly due to the accompanying Stefan type flow, and probably also as a result of the thermal diffusion. A pressure drop in the cavities is evidently made possible also by the pressure reduction in the flame which follows from the Hugoniot adiabatic theory.

  1. Detection of a flare at Fermi LAT energies during a multiwavelength campaign on Markarian 180

    NASA Astrophysics Data System (ADS)

    Sbarra, C.; Bastieri, D.; Fermi LAT Collaboration

    2012-11-01

    We present the results of the analysis of Markarian 180 (1ES 1133+704), a BL Lac object embedded in a giant elliptical galaxy, obtained for a period of 45 day, during which multi-wavelength observations were ongoing. The multi-wavelength campaign on Mrk180 was in 2008 (from 2008-10-24 to 2008-12-08) and was coordinated by Stefan Rugamer (MAGIC Collaboration). The Mrk 180 is associated with a quasar-like object whose distance can be determined unambiguously, thanks to the measurement of absorption line that gives the redshift (z=0.046; Ulrich 1978). The source was observed by the LAT of the Fermi satellite, and it was possible to discover a change of flux, at the energies 100 MeV-300 GeV, during the multi-wavelength campaign period. Results of the analysis are shown.

  2. Spreading and arrest of a molten liquid on cold substrates.

    PubMed

    Tavakoli, F; Davis, Stephen H; Kavehpour, H P

    2014-09-01

    Understanding the spreading and solidification of liquids on cold solid surfaces is a problem of fundamental importance and general utility. The physics of nonisothermal spreading followed by phase change is still a mystery. The present work focuses on the dynamics and thermal characteristics of liquid drop spreading and their subsequent arrest due to freezing. The spreading of liquid is recorded, and the evolution of the liquid spreading diameter and liquid-solid contact angle is measured from the recordings of a high-speed digital camera. After the initiation of solidification, the liquid drops are pinned to the substrate, showing fixed footprints and contact angles. A physical hypothesis using scaling is provided to explain the relationship between the arrested base diameter (D*) and arrested contact angle (θ*) with respect to the Stefan number (Ste). The experimental observations of solidified drops on cold substrates corroborate the derived physical theory. PMID:25115185

  3. Liquid helium-free cryostat and hermetically sealed cryogenic microwave cavity for hyperfine spectroscopy of antiprotonic helium.

    PubMed

    Massiczek, O; Friedreich, S; Juhász, B; Widmann, E; Zmeskal, J

    2011-12-11

    The design and properties of a new cryogenic set-up for laser-microwave-laser hyperfine structure spectroscopy of antiprotonic helium - an experiment performed at the CERN-Antiproton Decelerator (AD), Geneva, Switzerland - are described. Similar experiments for (4)He have been performed at the AD for several years. Due to the usage of a liquid helium operated cryostat and therefore necessary refilling of coolants, a loss of up to 10% beamtime occurred. The decision was made to change the cooling system to a closed-circuit cryocooler. New hermetically sealed target cells with minimised (3)He gas volume and different dimensions of the microwave resonator for measuring the (3)He transitions were needed. A new set-up has been designed and tested at Stefan Meyer Institute in Vienna before being used for the 2009 and 2010 beamtimes at the AD. PMID:22267883

  4. Cell scientist to watch--Irene Miguel-Aliaga.

    PubMed

    Miguel-Aliaga, Irene; Bobrowska, Anna

    2015-10-01

    Irene Miguel-Aliaga left sunny Barcelona to pursue a PhD at Oxford University in the laboratory of Kay Davies. She did her postdoctorate at Harvard University in Stefan Thor's lab, and briefly relocated with him to Sweden before coming back to the UK. She continued her postdoctoral work and developed her current research interests as a Marie Curie Fellow in the lab of Alex Gould at the National Institute for Medical Research in London. She established her own lab at the University of Cambridge in 2008, thanks to a Wellcome Trust Career Development Fellowship. In 2012 she moved to London and is currently a Programme Leader at the Medical Research Council Clinical Sciences Centre and a Reader at Imperial College London. Irene was elected to the EMBO Young Investigator programme and holds an ERC Starting Grant. Her lab investigates how gut cells maintain homeostasis and communicate with cells of other tissues and organs.

  5. Effects of anisotropic heat conduction on solidification

    SciTech Connect

    Weaver, J.A.; Viskanta, R.

    1989-01-01

    Two-dimensional solidfication influenced by anisotropic heat conductions has been considered. The interfacial energy balance was derived to account for the heat transfer in one direction (x or y) depending on the temperature gradient in both the x and y directions. A parametric study was made to determine the effect of Stefan number, aspect ratio, initial superheat, and thermal conductivity ratios on the solidification rate. Because of the imposed boundary conditions, the interface became skewed and sometimes was not a straight line between the interface position at the upper and lower adiabatic walls (spatially nonlinear along the height). This skewness depends on the thermal conductivity ratio k/sub yy//k/sub yx/. The nonlinearity of the interface is influenced by the solidificaton rate, aspect ratio, and k/sub yy//k/sub yx/.

  6. Geometric and Topological Methods for Quantum Field Theory

    NASA Astrophysics Data System (ADS)

    Cardona, Alexander; Contreras, Iván.; Reyes-Lega, Andrés. F.

    2013-05-01

    Introduction; 1. A brief introduction to Dirac manifolds Henrique Bursztyn; 2. Differential geometry of holomorphic vector bundles on a curve Florent Schaffhauser; 3. Paths towards an extension of Chern-Weil calculus to a class of infinite dimensional vector bundles Sylvie Paycha; 4. Introduction to Feynman integrals Stefan Weinzierl; 5. Iterated integrals in quantum field theory Francis Brown; 6. Geometric issues in quantum field theory and string theory Luis J. Boya; 7. Geometric aspects of the standard model and the mysteries of matter Florian Scheck; 8. Absence of singular continuous spectrum for some geometric Laplacians Leonardo A. Cano García; 9. Models for formal groupoids Iván Contreras; 10. Elliptic PDEs and smoothness of weakly Einstein metrics of Hölder regularity Andrés Vargas; 11. Regularized traces and the index formula for manifolds with boundary Alexander Cardona and César Del Corral; Index.

  7. Liquid helium-free cryostat and hermetically sealed cryogenic microwave cavity for hyperfine spectroscopy of antiprotonic helium.

    PubMed

    Massiczek, O; Friedreich, S; Juhász, B; Widmann, E; Zmeskal, J

    2011-12-11

    The design and properties of a new cryogenic set-up for laser-microwave-laser hyperfine structure spectroscopy of antiprotonic helium - an experiment performed at the CERN-Antiproton Decelerator (AD), Geneva, Switzerland - are described. Similar experiments for (4)He have been performed at the AD for several years. Due to the usage of a liquid helium operated cryostat and therefore necessary refilling of coolants, a loss of up to 10% beamtime occurred. The decision was made to change the cooling system to a closed-circuit cryocooler. New hermetically sealed target cells with minimised (3)He gas volume and different dimensions of the microwave resonator for measuring the (3)He transitions were needed. A new set-up has been designed and tested at Stefan Meyer Institute in Vienna before being used for the 2009 and 2010 beamtimes at the AD.

  8. Liquid helium-free cryostat and hermetically sealed cryogenic microwave cavity for hyperfine spectroscopy of antiprotonic helium

    PubMed Central

    Massiczek, O.; Friedreich, S.; Juhász, B.; Widmann, E.; Zmeskal, J.

    2011-01-01

    The design and properties of a new cryogenic set-up for laser–microwave–laser hyperfine structure spectroscopy of antiprotonic helium – an experiment performed at the CERN-Antiproton Decelerator (AD), Geneva, Switzerland – are described. Similar experiments for 4He have been performed at the AD for several years. Due to the usage of a liquid helium operated cryostat and therefore necessary refilling of coolants, a loss of up to 10% beamtime occurred. The decision was made to change the cooling system to a closed-circuit cryocooler. New hermetically sealed target cells with minimised 3He gas volume and different dimensions of the microwave resonator for measuring the 3He transitions were needed. A new set-up has been designed and tested at Stefan Meyer Institute in Vienna before being used for the 2009 and 2010 beamtimes at the AD. PMID:22267883

  9. /q-Thermostatistics and the black-body radiation problem

    NASA Astrophysics Data System (ADS)

    Martínez, S.; Pennini, F.; Plastino, A.; Tessone, C. J.

    2002-06-01

    We give an exact information-theory treatment of the n-dimensional black-body radiation process in a non-extensive scenario. We develop a q-generalization of the laws of (i) Stefan-Boltzmann, (ii) Planck, and (iii) Wien, and show that conventional, canonical results are obtained at temperatures above 1 K. Classical relationships between radiation, pressure, and internal energy are recovered (independently of the q value). Analyzing the particles’ density for q≈1, we see that the non-extensive parameter q introduces a fictitious chemical potential. We apply our results to experimental data on the cosmic microwave background and reproduce it with acceptable accuracy for different temperatures (each one associated to a particular q value).

  10. Feedback and sensitivity in an electrical circuit: An analog for climate models

    SciTech Connect

    Schwartz, S.E.

    2010-07-27

    Earth's climate sensitivity is often interpreted in terms of feedbacks that can alter the sensitivity from that of a no-feedback Stefan-Boltzmann radiator, with the feedback concept and algebra introduced by analogy to the use of this concept in the electronics literature. This analogy is quite valuable in interpreting the sensitivity of the climate system, but usage of this algebra and terminology in the climate literature is often inconsistent, with resultant potential for confusion and loss of physical insight. Here a simple and readily understood electrical resistance circuit is examined in terms of feedback theory to introduce and define the terminology that is used to quantify feedbacks. This formalism is applied to the feedbacks in an energy-balance model of Earth's climate and used to interpret the magnitude of feedback in the climate system that corresponds to present estimates of Earth's climate sensitivity.

  11. Numerical Simulation of Heat and Mass Transfer in an Ejection Apparatus

    NASA Astrophysics Data System (ADS)

    Kologrivov, M. M.; Buzovskii, V. P.

    2016-01-01

    The results of numerical simulation of heat and mass transfer in an ejection apparatus during condensation of vapor-gas mixture components on cold brine droplets are presented. The local parameters of working flows were determined by solving a system of differential heat transfer equations with account for the hydrodynamic pattern. Calculations were carried out on the assumption that the liquid spray is directed horizontally. The Stefan formula has been derived with reference to a spherical coordinate system. The results of calculation of heat and mass transfer rates with and without regard for steam condensation jointly with hydrocarbon vapors are compared and analyzed. Estimation of the effect exerted by the apparatus and drip pan walls on the general process of heat and mass transfer was carried out. The results of simulation made it possible to quantitatively estimate the influence of the adopted thickness of the diffusional boundary layer on the vapor-air mixture cooling effect.

  12. Fundamental Study of Direct Contact Cold Energy Release by Flowing Hot Air through Ice Particles Packed Layer

    NASA Astrophysics Data System (ADS)

    Aoyama, Sigeo; Inaba, Hideo

    This paper has dealt with the direct contact heat exchange characteristics between ice particles (average ice particle diameter : 3.10mm) packed in the rectangular cold energy storage vessel and flowing hot air as a heat transfer medium. The hot air bubbles ascended in the fluidized ice particles layer, and they were cooled down directly by melting ice particles. The temperature efficiency increased as Reynolds number Re increased because the hot air flowing in the layer became active. The dehumidity efficiency increased with an increase in modified Stefan number and Re, since the heat capacity of inlet air and heat transfer coefficient increased. Finally, some empirical correlations for temperature efficiency, dehumidity efficiency and the completion time of cold energy release were derived in terms of various nondimensional parameters.

  13. Cell scientist to watch--Melina Schuh.

    PubMed

    Schuh, Melina; Bobrowska, Anna

    2016-01-01

    Melina Schuh received her diploma degree in biochemistry from the University of Bayreuth, Germany, where she completed her Diploma thesis with Stefan Heidmann and Christian Lehner. She went on to do her PhD with Jan Ellenberg at the European Molecular Biology Laboratory in Heidelberg, Germany. In 2009, after a bridging postdoc with Jan, Melina started her own group at the MRC Laboratory of Molecular Biology in Cambridge, UK. Since January 2016, she is a Director at the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany, and will establish a new department focussing on meiosis. She is an EMBO Young Investigator and a recipient of the 2014 Lister Institute Research Prize, the 2014 Biochemical Society Early Career Award and the 2015 John Kendrew Young Scientist Award. Her lab is studying meiosis in mammalian oocytes, including human oocytes.

  14. Compatibility of Payload Equipment for Monitoring of the Seismoionospheric Precursors.*

    NASA Astrophysics Data System (ADS)

    Ruzhin, Yu. Ya.; Depueva, A. Kh.; Stefan, V.

    1996-11-01

    The earthquake prediction including precursors appearance and their detection on the Earth's surface and at ionospheric altitudes is a matter of high interest.^2 Present warning systems are based on ground-based monitoring data. Satellite monitoring represents, due to some well known advantages (global scale, continuous records, etc.) a significant progress in the area. It is shown that by means of one payload it is possible to monitor all main parameters of seismoionospheric precursors. The active methods and airglow imager are used for detection of anomalous plasma structure during a few days before first shock. Supported in part by Tesla Labs, Inc., La Jolla, CA 92038-2946. ^1Also with Tesla Labs, Inc., La Jolla, CA 92038-2946. ^2V. Stefan (Editor-in-Chief). Environmental Physics. Frontiers in Interdisciplinary Physics series of the La Jolla International School of Physics, The Institute for Advanced Physics Studies, La Jolla, CA (IAPS Press, La Jolla, 1996).

  15. Plunge location of sediment driven hyperpycnal river discharges considering bottom friction, lateral entrainment, and particle settling

    NASA Astrophysics Data System (ADS)

    Strom, K. B.; Bhattacharya, J.

    2012-12-01

    River discharges with very high sediment loads have the potential to develop into plunging hyperpycnal flows that transition from a river jet to a turbidity current at some location basinward of the river mouth due to the density difference between the turbid river and the receiving water body. However, even if the bulk density of the turbid river is greater than that of the receiving lake or ocean, some distance is needed for the forward inertia of the river to dissipate so that the downward gravitational pull can cause the system to collapse into a subaqueous turbidity current. This collapsing at the plunge point has been found to occur when the densimetric Froude number decreases to a value between 0.3 < Frd < 0.7 (Fang and Stefan 2000, Parker and Toniolo 2007, Dai and Garcia 2010, Lamb et al. 2010). In 2D channel flow analysis at the plunge point, this has led to the concept of a two-fold criterion for plunging. The first is simply for the need of high enough suspended sediment concentration to overcome the density difference between the river fluid and the fluid of the receiving water. The second is the need for sufficiently deep water to reduce the densimetric Froude below the critical value for plunging, which leads to dependence of plunging on the receiving water basin topography (Lamb et al. 2010). In this analysis, we expand on past work by solving a system of ODE river jet equations to account for bottom friction, lateral entrainment of ambient fluid, and particle settling between the river mouth and the plunge location. Typical entrainment and bottom friction coefficients are used and the model is tested against the laboratory density current data of Fang and Stefan (1991). A suite of conditions is solved with variable river discharge velocity, aspect ratio, suspended sediment concentration, and particle size; a range of salinity values and bottom slopes are used for the receiving water body. The plunge location is then expressed as a function of the

  16. Tritium Measurements in Slovenia - Chronology Till 2004

    SciTech Connect

    Logar, Jasmina Kozar; Vaupotic, Janja; Kobal, Ivan

    2005-07-15

    Almost all the analyses of tritium in Slovenia have been performed by the tritium laboratory at the Jozef Stefan Institute. Nearly 90 % of its measurements have been covered by two national programs, both approved by the Slovenian Nuclear Safety Administration: the radioactive monitoring program in the environs of Krsko Nuclear Power Plant (KNPP) and the program of global radioactive contamination monitoring in the environment. These programs include samples of groundwaters, surface waters, precipitation and drinking waters, as well as liquid and gaseous effluents from KNPP. Tritium was determined in some research projects and in hydrological studies of thermal waters, groundwater and coalmine waters. Tritium in the Karst region was mapped as well as the springs of entire territory of Slovenia. Around 5500 samples have been analyzed up to 2004.

  17. Thermally induced structural changes in coal combustion

    SciTech Connect

    Gavalas, G.R.; Flagan, R.C.

    1990-01-17

    The effect of particle shape on char burnout is investigated in the limit of shrinking core combustion. As a first step, the particle temperature is assumed to proceed in the shrinking core regime and under conditions of negligible Stefan flow. The problem then reduces to calculating the oxygen concentration field around a non-spherical particle with the oxidation reaction taking place on the external surface. This problem has been addressed by an analytical technique and a numerical technique. An analytical technique known as domain perturbation'' was used to examine the change due to reaction in the shape of a slightly nonspherical, but axisymmetric, particle. It was found that the aspect ratio always increases with conversion, i.e., the particle becomes less spherical. A numerical technique, based on the boundary integral'' method was developed to handle the case of an axisymmetric particle with otherwise arbitrary shape. Numerical results are presented which again show the aspect ratio to increase with conversion. 8 refs.

  18. [Inadequate burials as an important factor in plague epidemic amongst Serbs in the Habsburg monarchy by the end of the 18th century: a historical analysis].

    PubMed

    Vasin, Goran; Božanić, Snežana; Božić, Milica Kisić

    2014-01-01

    Analysis of the archaic customs of burying the deceased in Srem, primarily amongst Serbs, in the second half of the 18th century is the essential part of the paper that aims at clarifying the consequences of this negative habit onto the spreading of plague epidemic. The Austrian Empire tried to stop and prevent the epidemic with an array of legal norms, but in practice, these orders were often not upheld. Serbian Metropolitans Pavle Nenadović and Stefan Stratimirović insisted on eradicating superstition and retrograde, often uncivilized actions in burial rituals, and they partially succeeded. The example of plague in Irig and the surroundings in 1795-1796 explicitly shows the hazardous effects of the inadequate attitude towards the deceased as one of the factors in spreading the epidemic. Using primary archives, and published sources, with adequate literature, authors depict this complex historical process.

  19. Mathematical modeling of the heat treatment and combustion of a coal particle. II. drying stage

    NASA Astrophysics Data System (ADS)

    Enkhzhargal, Kh.; Salomatov, V. V.

    2011-03-01

    This article is a continuation of the previous article in which, with the aid of mathematical modeling, the regime of radiative-convective heating of a coal particle was studied in detail and which was devoted to an analysis of the stage of coal drying, very important in the general picture of coal combustion. The process of coal drying is formulated as the nonlinear Stefan problem with a moving liquid-vapor phase change interface. The rate and time of coal particle drying, the temperature distribution inside a particle, and other parameters of the process have been found approximately analytically depending on the regime of heat supply. A parametric analysis of the influence of physical and regime factors on the dynamics of drying as an integral part of heat treatment of a fuel for its ignition and combustion has been carried out.

  20. Deformation and solidification of molten particles on a substrate in thermal plasma spraying

    SciTech Connect

    Pasandideh-Fard, M.; Mostaghimi, J.

    1994-12-31

    In the present study, the flattening and simultaneous solidification of a liquid droplet upon its impingement onto a solid surface has been numerically simulated and an extensive set of results has been generated to represent this complex deformation process. The numerical solution for the complete Navier-Stokes equations is based on the modified SOLA-VOF method using rectangular mesh in axisymmetric geometry. For the solidification part of the deformation process, based on a one dimensional Stefan problem in heat conduction, a numerical procedure has been developed. The results for the complete deformation process and the effect of some important input data including impact velocity, droplet diameter, viscosity, surface tension and contact angle have been discussed. Comparing the predictions with some available data reveals a good agreement, therefore, the model may be considered to be well suited for investigating the droplet deformation.