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Sample records for schramm-loewner evolution sle

  1. Schramm-Loewner evolution and Liouville quantum gravity.

    Science.gov (United States)

    Duplantier, Bertrand; Sheffield, Scott

    2011-09-23

    We show that when two boundary arcs of a Liouville quantum gravity random surface are conformally welded to each other (in a boundary length-preserving way) the resulting interface is a random curve called the Schramm-Loewner evolution. We also develop a theory of quantum fractal measures (consistent with the Knizhnik-Polyakov-Zamolochikov relation) and analyze their evolution under conformal welding maps related to Schramm-Loewner evolution. As an application, we construct quantum length and boundary intersection measures on the Schramm-Loewner evolution curve itself.

  2. Left passage probability of Schramm-Loewner Evolution

    Science.gov (United States)

    Najafi, M. N.

    2013-06-01

    SLE(κ,ρ⃗) is a variant of Schramm-Loewner Evolution (SLE) which describes the curves which are not conformal invariant, but are self-similar due to the presence of some other preferred points on the boundary. In this paper we study the left passage probability (LPP) of SLE(κ,ρ⃗) through field theoretical framework and find the differential equation governing this probability. This equation is numerically solved for the special case κ=2 and hρ=0 in which hρ is the conformal weight of the boundary changing (bcc) operator. It may be referred to loop erased random walk (LERW) and Abelian sandpile model (ASM) with a sink on its boundary. For the curve which starts from ξ0 and conditioned by a change of boundary conditions at x0, we find that this probability depends significantly on the factor x0-ξ0. We also present the perturbative general solution for large x0. As a prototype, we apply this formalism to SLE(κ,κ-6) which governs the curves that start from and end on the real axis.

  3. Six-vertex model and Schramm-Loewner evolution

    Science.gov (United States)

    Kenyon, Richard; Miller, Jason; Sheffield, Scott; Wilson, David B.

    2017-05-01

    Square ice is a statistical mechanics model for two-dimensional ice, widely believed to have a conformally invariant scaling limit. We associate a Peano (space-filling) curve to a square ice configuration, and more generally to a so-called six-vertex model configuration, and argue that its scaling limit is a space-filling version of the random fractal curve SL E κ, Schramm-Loewner evolution with parameter κ , where 4 <κ ≤12 +8 √{2 } . For square ice, κ =12 . At the "free-fermion point" of the six-vertex model, κ =8 +4 √{3 } . These unusual values lie outside the classical interval 2 ≤κ ≤8 .

  4. Stochastic geometry of critical curves, Schramm-Loewner evolutions and conformal field theory

    International Nuclear Information System (INIS)

    Gruzberg, Ilya A

    2006-01-01

    Conformally invariant curves that appear at critical points in two-dimensional statistical mechanics systems and their fractal geometry have received a lot of attention in recent years. On the one hand, Schramm (2000 Israel J. Math. 118 221 (Preprint math.PR/9904022)) has invented a new rigorous as well as practical calculational approach to critical curves, based on a beautiful unification of conformal maps and stochastic processes, and by now known as Schramm-Loewner evolution (SLE). On the other hand, Duplantier (2000 Phys. Rev. Lett. 84 1363; Fractal Geometry and Applications: A Jubilee of Benot Mandelbrot: Part 2 (Proc. Symp. Pure Math. vol 72) (Providence, RI: American Mathematical Society) p 365 (Preprint math-ph/0303034)) has applied boundary quantum gravity methods to calculate exact multifractal exponents associated with critical curves. In the first part of this paper, I provide a pedagogical introduction to SLE. I present mathematical facts from the theory of conformal maps and stochastic processes related to SLE. Then I review basic properties of SLE and provide practical derivation of various interesting quantities related to critical curves, including fractal dimensions and crossing probabilities. The second part of the paper is devoted to a way of describing critical curves using boundary conformal field theory (CFT) in the so-called Coulomb gas formalism. This description provides an alternative (to quantum gravity) way of obtaining the multifractal spectrum of critical curves using only traditional methods of CFT based on free bosonic fields

  5. SLE as a Mating of Trees in Euclidean Geometry

    Science.gov (United States)

    Holden, Nina; Sun, Xin

    2018-05-01

    The mating of trees approach to Schramm-Loewner evolution (SLE) in the random geometry of Liouville quantum gravity (LQG) has been recently developed by Duplantier et al. (Liouville quantum gravity as a mating of trees, 2014. arXiv:1409.7055). In this paper we consider the mating of trees approach to SLE in Euclidean geometry. Let {η} be a whole-plane space-filling SLE with parameter {κ > 4} , parameterized by Lebesgue measure. The main observable in the mating of trees approach is the contour function, a two-dimensional continuous process describing the evolution of the Minkowski content of the left and right frontier of {η} . We prove regularity properties of the contour function and show that (as in the LQG case) it encodes all the information about the curve {η} . We also prove that the uniform spanning tree on {Z^2} converges to SLE8 in the natural topology associated with the mating of trees approach.

  6. Possible description of domain walls in two-dimensional spin glasses by stochastic Loewner evolutions

    International Nuclear Information System (INIS)

    Bernard, Denis; Le Doussal, Pierre; Middleton, A. Alan

    2007-01-01

    Domain walls for spin glasses are believed to be scale invariant; a stronger symmetry, conformal invariance, has the potential to hold. The statistics of zero-temperature Ising spin glass domain walls in two dimensions are used to test the hypothesis that these domain walls are described by a Schramm-Loewner evolution SLE κ . Multiple tests are consistent with SLE κ , where κ=2.32±0.08. Both conformal invariance and the domain Markov property are tested. The latter does not hold in small systems, but detailed numerical evidence suggests that it holds in the continuum limit

  7. SLE in self-dual critical Z(N) spin systems: CFT predictions

    International Nuclear Information System (INIS)

    Santachiara, Raoul

    2008-01-01

    The Schramm-Loewner evolution (SLE) describes the continuum limit of domain walls at phase transitions in two-dimensional statistical systems. We consider here the SLE in Z(N) spin models at their self-dual critical point. For N=2 and N=3 these models correspond to the Ising and three-state Potts model. For N≥4 the critical self-dual Z(N) spin models are described in the continuum limit by non-minimal conformal field theories with central charge c≥1. By studying the representations of the corresponding chiral algebra, we show that two particular operators satisfy a two level null vector condition which, for N≥4, presents an additional term coming from the extra symmetry currents action. For N=2,3 these operators correspond to the boundary conditions changing operators associated to the SLE 16/3 (Ising model) and to the SLE 24/5 and SLE 10/3 (three-state Potts model). We suggest a definition of the interfaces within the Z(N) lattice models. The scaling limit of these interfaces is expected to be described at the self-dual critical point and for N≥4 by the SLE 4(N+1)/(N+2) and SLE 4(N+2)/(N+1) processes

  8. SLE local martingales, reversibility and duality

    Energy Technology Data Exchange (ETDEWEB)

    Kytoelae, Kalle; Kemppainen, Antti [Department of Mathematics and Statistics, PO Box 68, FIN-00014 University of Helsinki (Finland)

    2006-11-17

    We study Schramm-Loewner evolutions (SLEs) reversibility and duality using the Virasoro structure of the space of local martingales. For both problems we formulate a setup where the questions boil down to comparing two processes at a stopping time. We state algebraic results showing that local martingales for the processes have enough in common. When one has in addition integrability, the method gives reversibility and duality for any polynomial expected value. (letter to the editor)

  9. SLE local martingales, reversibility and duality

    International Nuclear Information System (INIS)

    Kytoelae, Kalle; Kemppainen, Antti

    2006-01-01

    We study Schramm-Loewner evolutions (SLEs) reversibility and duality using the Virasoro structure of the space of local martingales. For both problems we formulate a setup where the questions boil down to comparing two processes at a stopping time. We state algebraic results showing that local martingales for the processes have enough in common. When one has in addition integrability, the method gives reversibility and duality for any polynomial expected value. (letter to the editor)

  10. Hydrodynamic Limit of Multiple SLE

    Science.gov (United States)

    Hotta, Ikkei; Katori, Makoto

    2018-04-01

    Recently del Monaco and Schleißinger addressed an interesting problem whether one can take the limit of multiple Schramm-Loewner evolution (SLE) as the number of slits N goes to infinity. When the N slits grow from points on the real line R in a simultaneous way and go to infinity within the upper half plane H, an ordinary differential equation describing time evolution of the conformal map g_t(z) was derived in the N → ∞ limit, which is coupled with a complex Burgers equation in the inviscid limit. It is well known that the complex Burgers equation governs the hydrodynamic limit of the Dyson model defined on R studied in random matrix theory, and when all particles start from the origin, the solution of this Burgers equation is given by the Stieltjes transformation of the measure which follows a time-dependent version of Wigner's semicircle law. In the present paper, first we study the hydrodynamic limit of the multiple SLE in the case that all slits start from the origin. We show that the time-dependent version of Wigner's semicircle law determines the time evolution of the SLE hull, K_t \\subset H\\cup R, in this hydrodynamic limit. Next we consider the situation such that a half number of the slits start from a>0 and another half of slits start from -a exact solutions, we will discuss the universal long-term behavior of the multiple SLE and its hull K_t in the hydrodynamic limit.

  11. Stochastic Loewner evolution as an approach to conformal field theory

    International Nuclear Information System (INIS)

    Mueller-Lohmann, Annekathrin

    2008-01-01

    The main focus on this work lies on the relationship between two-dimensional boundary Conformal Field Theories (BCFTs) and SCHRAMM-LOEWNER Evolutions (SLEs) as motivated by their connection to the scaling limit of Statistical Physics models at criticality. The BCFT approach used for the past 25 years is based on the algebraic formulation of local objects such as fields and their correlations in these models. Introduced in 1999, SLE describes the physical properties from a probabilistic point of view, studying measures on growing curves, i.e. global objects such as cluster interfaces. After a short motivation of the topic, followed by a more detailed introduction to two-dimensional boundary Conformal Field Theory and SCHRAMM-LOEWNER Evolution, we present the results of our original work. We extend the method of obtaining SLE variants for a change of measure of the single SLE to derive the most general BCFT model that can be related to SLE. Moreover, we interpret the change of the measure in the context of physics and Probability Theory. In addition, we discuss the meaning of bulk fields in BCFT as bulk force-points for the SLE variant SLE (κ, vector ρ). Furthermore, we investigate the short-distance expansion of the boundary condition changing fields, creating cluster interfaces that can be described by SLE, with other boundary or bulk fields. Thereby we derive new SLE martingales related to the existence of boundary fields with vanishing descendant on level three. We motivate that the short-distance scaling law of these martingales as adjustment of the measure can be interpreted as the SLE probability of curves coming close to the location of the second field. Finally, we extend the algebraic κ-relation for the allowed variances in multiple SLE, arising due to the commutation requirement of the infinitesimal growth operators, to the joint growth of two SLE traces. The analysis straightforwardly suggests the form of the infinitesimal LOEWNER mapping of joint

  12. Scale-invariant puddles in graphene: Geometric properties of electron-hole distribution at the Dirac point.

    Science.gov (United States)

    Najafi, M N; Nezhadhaghighi, M Ghasemi

    2017-03-01

    We characterize the carrier density profile of the ground state of graphene in the presence of particle-particle interaction and random charged impurity in zero gate voltage. We provide detailed analysis on the resulting spatially inhomogeneous electron gas, taking into account the particle-particle interaction and the remote Coulomb disorder on an equal footing within the Thomas-Fermi-Dirac theory. We present some general features of the carrier density probability measure of the graphene sheet. We also show that, when viewed as a random surface, the electron-hole puddles at zero chemical potential show peculiar self-similar statistical properties. Although the disorder potential is chosen to be Gaussian, we show that the charge field is non-Gaussian with unusual Kondev relations, which can be regarded as a new class of two-dimensional random-field surfaces. Using Schramm-Loewner (SLE) evolution, we numerically demonstrate that the ungated graphene has conformal invariance and the random zero-charge density contours are SLE_{κ} with κ=1.8±0.2, consistent with c=-3 conformal field theory.

  13. A case of brain SLE: MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Soon; Kim, Seung Min [Wonju College of Medicine, Yonsei University, Wonju (Korea, Republic of)

    1992-01-15

    Systemic lupus erythematosus(SLE) is an autoimmune disease characterized by multisystem involvement including central nervous system and various neurologic symptoms. The authors experienced a case of brain SLE and report MRI and other neuroimaging findings.

  14. Haemorrhagic SLE In A Young Male

    Directory of Open Access Journals (Sweden)

    Rajagopal R

    2002-01-01

    Full Text Available Systemic lupus erythematous (SLE is a systemic autoimmune disease that tends to occur in early adult life. The peak age of onset of the first symptom or sign in females is about 38 years and later in men, at about 44 years. Females outnumber men in this illness in a ratio of about 8 : 1. Cutaneous lesions in male have not been properly investigated and some studies in male with SLE have shown that the illness may present with atypical skin lesions. A case of SLE in a 20 year male who developed sudden onset of haemorrhagic vesiculobullous butterfly rash is described.

  15. Epidemiologi ved systemisk lupus erythematosus (SLE

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    Inge-Margrethe Gilboe

    2009-10-01

    Full Text Available Det er utført få epidemiologiske studier av SLE i Norge. De studier som er utført viser liknende hyppighet og forekomst av SLE i Norge som i de øvrige nordiske land og forekomst av mild sykdom med en lav andel av alvorlig indre organ manifestasjoner. Insidens og prevalens er kartlagt i Nord-Norge visende en lavere insidens enn i de øvrige nordiske land, mens prevalensen er sammenliknbar. Tall fra Sverige tyder på stabil insidens, men økende prevalens, forenelig med økt overlevelse. Norske og nordiske studier viser høy kvinneandel og sammenliknbar alder ved diagnose. Studiene tyder på en høyere alder ved diagnose i Skandinavia enn i USA og England. Ut fra de nordiske studier er overlevelsen ved SLE god, selv om den er lavere enn i den generelle befolkningen. Overlevelse i de nordiske og europeiske land er sammenliknbare.Selv om overlevelsen ved SLE er betydelig bedret over tid utgjorde aktiv SLE og infeksjoner 50% av dødsårsakene i den danske mortalitetsstudien. Aterosklerotisk hjerte-karsykdom var en hyppig dødsårsak i alle studiene. Kardiovaskulær sykdom som hovedårsak til død ved SLE er påvist i den store internasjonale studien hvor pasienter fra Island og Sverige deltok og i andre europeiske og internasjonale studier. Betydelig økt risiko for hjerteinfarkt hos unge SLE-kvinner i Sverige er også påvist tidligere i internasjonale studier og styrker teorien om at SLE per ce er en selvstendig risikofaktor for aterosklerose. Det er ønskelig med flere epidemiologiske studier av SLE i Norge.There has been few studies on the epidemiology of SLE in Norway. The studies that have been conducted show similar frequency and occurence of SLE in Norway in comparison to the other Nordic countries, and mainly occurence of mild disease with only a low proportion suffering severe internal organ involvement. Studies on incidence and prevalence in the northern part of Norway show a lower incidence than in other Nordic countries, but a

  16. The SLE heart in scintigraphic diagnostics

    International Nuclear Information System (INIS)

    Rottensteiner, J.

    2001-01-01

    Investigation of SLE-heart of 14 patients with 201Ti-SPECT and 18 FDG-SPECT and comparison with clinical and laboratory parameters. Results: SLE-patients with unspecific heart symptoms show in spite of sufficiently perfusion in 201Ti-SPECT considerable defects in 18-FDG. Interpretation: cause of the defects in FDG in a disturbed glucose metabolism independent of perfusion. (boteke)

  17. Dicty_cDB: SLE232 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SL (Link to library) SLE232 (Link to dictyBase) - - - Contig-U16255-1 SLE232F (Link... to Original site) SLE232F 614 - - - - - - Show SLE232 Library SL (Link to library) Clone ID SLE232 (Link to dict...yBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U16255-1 Original site URL http://dict...PSSGFTDFIPSNATCSSLNCNAQQMSCKYVQQACHETSCCPDIPQC QIPATGGGPATGSATGQGTSGGTPGSCDKVNCPNGYICTIVNQLAVCVSPSSSSSSSSST ...CHETSCCPDIPQC QIPATGGGPATGSATGQGTSGGTPGSCDKVNCPNGYICTIVNQLAVCVSPSSSSSSSSST TGSHTTTGGSTTGSHTTTGGSTTGSHTTTGGSA

  18. Protective Role of Ets1 in SLE

    Science.gov (United States)

    2014-07-01

    Purification and differentiation of Th cells were performed according to a published protocol without modi - fication (3). Preparation of Cytoplasmic...RA), systemic lupus erythematosus (SLE), and type 1 diabetes but reduces the risk of Crohn’s disease [7,14-17]. Despite these observations, it is

  19. Children born to SLE and APS mothers.

    Science.gov (United States)

    Nalli, C; Iodice, A; Andreoli, L; Lojacono, A; Motta, M; Fazzi, E; Tincani, A

    2014-10-01

    Systemic lupus erythematosus (SLE) and antiphospholipid antibody syndrome (APS) are autoimmune diseases that affect women of childbearing age. Pregnancies in these patients carry several complications such as prematurity. Maternal IgG antiphospholipid antibodies (aPL) can cross the placenta but they don't generally cause any neonatal thrombotic event. Because of the incompleteness of the fetal blood-brain barrier, aPL could theoretically reach the fetal brain. Whether this can have an effect on brain development is still under investigation. Some studies performed in children of patients with SLE and/or APS showed an increased number of learning disabilities without impairment in intelligence level. The objectives of this article are to evaluate the neurodevelopment outcome in 30 children (median age 9 years) born to mothers with SLE and/or APS with IgG anti-beta2-glycoprotein I during the third trimester of pregnancy and found positive for the same antibodies at birth. A neurological physical exam was performed in all children. We submitted some questionnaires to the mothers: the Child Behavior CheckList (CBCL) and a homemade set of questions obtained by a team composed of rheumatologists and pediatric neurologists. Intellectual functioning was determined by the Wechsler scale for corrected age. In all children neurological physical exam and intelligence levels were found to be normal but mild behavior disorders and history of neurological manifestations were shown in three children. Offspring of patients with SLE and/or APS are generally healthy. We and others observed the occurrence of minor neurological disorders that might be related to maternal disease or to prematurity. The limited number of the available data on this sensitive issue supports the need for further studies. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  20. SLE local martingales in logarithmic representations

    International Nuclear Information System (INIS)

    Kytölä, Kalle

    2009-01-01

    A space of local martingales of SLE-type growth processes forms a representation of Virasoro algebra, but apart from a few simplest cases, not much is known about this representation. The purpose of this paper is to exhibit examples of representations where L 0 is not diagonalizable—a phenomenon characteristic of logarithmic conformal field theory. Furthermore, we observe that the local martingales bear a close relation to the fusion product of the boundary changing fields. Our examples reproduce first of all many familiar logarithmic representations at certain rational values of the central charge. In particular we discuss the case of SLE κ=6 describing the exploration path in critical percolation and its relation to the question of operator content of the appropriate conformal field theory of zero central charge. In this case one encounters logarithms in a probabilistically transparent way, through conditioning on a crossing event. But we also observe that some quite natural SLE variants exhibit logarithmic behavior at all values of κ, thus at all central charges and not only at specific rational values

  1. Hydroxychloroquine in systemic lupus erythematosus (SLE).

    Science.gov (United States)

    Ponticelli, C; Moroni, G

    2017-03-01

    Hydroxychloroquine (HCQ) is an alkalinizing lysosomatropic drug that accumulates in lysosomes where it inhibits some important functions by increasing the pH. HCQ has proved to be effective in a number of autoimmune diseases including systemic lupus erythematosus (SLE). Areas covered: In this review the mechanisms of action, the efficacy, and the safety of HCQ in the management of patients with SLE have been reviewed. HCQ may reduce the risk of flares, allow the reduction of the dosage of steroids, reduce organ damage, and prevent the thrombotic effects of anti-phospholipid antibodies. The drug is generally safe and may be prescribed to pregnant women. However, some cautions are needed to prevent retinopathy, a rare but serious complication of the prolonged use of HCQ. Expert opinion: HCQ may offer several advantages not only in patients with mild SLE but can also exert important beneficial effects in lupus patients with organ involvement and in pregnant women. The drug has a low cost and few side effects. These characteristics should encourage a larger use of HCQ, also in lupus patients with organ involvement.

  2. Dicty_cDB: SLE110 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SL (Link to library) SLE110 (Link to dictyBase) - - - Contig-U16520-1 SLE110E (Link... to Original site) - - - - - - SLE110E 237 Show SLE110 Library SL (Link to library) Clone ID SLE110 (Link to dict...yBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U16520-1 Original site URL http://dict...NLSEDVNLEEFVMSKDDLSGADIKAICTESGLLALRERRMRVTYXDFKKAKEKVLYR KTAGAPEGLYM*kkknqnq Translated Amino Acid sequence... (All Frames) Frame A: AKMNLSEDVNLEEFVMSKDDLSGADIKAICTESGLLALRERRMRVTYXDFKKAKEKVL

  3. A framework for remission in SLE

    DEFF Research Database (Denmark)

    van Vollenhoven, Ronald; Voskuyl, Alexandre; Bertsias, George

    2017-01-01

    , for example, clinical systemic lupus erythematosus disease activity index (SLEDAI)=0, British Isles lupus assessment group (BILAG) 2004 D/E only, clinical European consensus lupus outcome measure (ECLAM)=0; with routine laboratory assessments included, and supplemented with physician's global assessment.3....... Distinction is made between remission off and on therapy: remission off therapy requires the patient to be on no other treatment for SLE than maintenance antimalarials; and remission on therapy allows patients to be on stable maintenance antimalarials, low-dose corticosteroids (prednisone ≤5 mg...

  4. Psychiatric disorders in systemic lupus erythematosus (SLE: a serious SLE-related crime

    Directory of Open Access Journals (Sweden)

    Gabriele Nicolosi

    2013-04-01

    Full Text Available Introduction: Systemic lupus erythematosus (SLE is associated with CNS disorders in 50-90% of all cases. Thus far 19 neuropsychiatric syndromes have been reported in association with SLE, and many others will be added to this list in the future. Long-term observation and use of the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (Text Revision is the solution for a correct diagnosis. Case report: The patient was an 18-year-old woman who had been charged with the attempted murder of an elderly woman in the latter’s home. According to the victim’s testimony, the young woman had entered the victim’s home under pretence and suddently attacked her with a hammer. The young woman denied all knowledge of the event. A few days after her arrest the patient was hospitalized for attempted suicide. The work-up that began with this hospitalization led to the diagnosis of an intermittent explosive disorder secondary to SLE. The authors analyze this case from the psychiatric, medical, and legal points of view. Conclusions: This is the first report of this type of disorder is a patient with SLE. The authors suggest that intermittent explosive disorder should be added to the list of neuropsychiatric syndromes associated with this disease.

  5. Autoantibodies in SLE: Specificities, Isotypes and Receptors

    Directory of Open Access Journals (Sweden)

    Barbara Dema

    2016-01-01

    Full Text Available Systemic Lupus Erythematosus (SLE is characterized by a wide spectrum of auto-antibodies which recognize several cellular components. The production of these self-reactive antibodies fluctuates during the course of the disease and the involvement of different antibody-secreting cell populations are considered highly relevant for the disease pathogenesis. These cells are developed and stimulated through different ways leading to the secretion of a variety of isotypes, affinities and idiotypes. Each of them has a particular mechanism of action binding to a specific antigen and recognized by distinct receptors. The effector responses triggered lead to a chronic tissue inflammation. DsDNA autoantibodies are the most studied as well as the first in being characterized for its pathogenic role in Lupus nephritis. However, others are of growing interest since they have been associated with other organ-specific damage, such as anti-NMDAR antibodies in neuropsychiatric clinical manifestations or anti-β2GP1 antibodies in vascular symptomatology. In this review, we describe the different auto-antibodies reported to be involved in SLE. How autoantibody isotypes and affinity-binding to their antigen might result in different pathogenic responses is also discussed.

  6. Auricular Chondritis in a Postpartum Flare of SLE and APS

    Directory of Open Access Journals (Sweden)

    Elodie Ponce

    2014-10-01

    Full Text Available Introduction: Auricular chondritis has been occasionally described in patients with systemic lupus erythematosus (SLE and antiphospholipid syndrome (APS. Materials and methods: We report the case of a woman with a previous history of APS who presented with auricular chondritis with onset of SLE symptoms during the postpartum period. Conclusion: SLE and APS should be taken into consideration in the differential diagnosis of auricular chondritis.

  7. Disease characterization of systemic lupus erythematosus (SLE) patients in Quebec.

    Science.gov (United States)

    Ng, R; Bernatsky, S; Rahme, E

    2017-08-01

    Objective Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by an array of organ manifestations that can appear during flares and disappear during remissions. The objectives of this study were: (i) to examine SLE manifestation groups longitudinally in an SLE cohort; and (ii) to assess the association between early antimalarial treatment and renal manifestations. Methods Seven SLE manifestation groups-cutaneous, hematologic, lung, musculoskeletal, neuropsychiatric, serositis, renal-were tracked using Kaplan-Meier survival curves in an incident SLE cohort from Quebec health administrative data ( n = 2010). A subgroup with provincial drug insurance coverage was followed over time to examine the association between early antimalarial treatment (within three months after SLE diagnosis) and renal manifestations using a Cox proportional hazards survival model. Results Cutaneous manifestations was the most common manifestation at SLE diagnosis (30.0%, 95% CI: 27.7-32.2%). About two-thirds (66.2%, 95% CI: 63.4-68.9%) of patients had evidence of at least one SLE manifestation at diagnosis, which increased to 87.2% (95% CI: 84.2-90.3%) by the end of follow-up. After adjusting for age, sex, early concomitant systemic steroid therapy, Charlson comorbidity index, primary care visits in the year prior and other SLE manifestations at baseline, no statistically significant association was established between antimalarial therapy and renal manifestations. Conclusion This study provides insight regarding organ manifestations within a population-based sample. Most patients identified with SLE had other diagnostic evidence that supports an underlying diagnosis of SLE. No protective effects for antimalarial agents against renal manifestations could be established in this population-based cohort.

  8. Hypothyroidism among SLE patients: Case-control study.

    Science.gov (United States)

    Watad, Abdulla; Mahroum, Naim; Whitby, Aaron; Gertel, Smadar; Comaneshter, Doron; Cohen, Arnon D; Amital, Howard

    2016-05-01

    The prevalence of hypothyroidism in SLE patients varies considerably and early reports were mainly based on small cohorts. To investigate the association between SLE and hypothyroidism. Patients with SLE were compared with age and sex-matched controls regarding the proportion of hypothyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study was performed utilizing the medical database of Clalit Health Services. The study included 5018 patients with SLE and 25,090 age and sex-matched controls. The proportion of hypothyroidism in patients with SLE was increased compared with the prevalence in controls (15.58% and 5.75%, respectively, Phypothyroidism (odds ratio 2.644, 95% confidence interval 2.405-2.908). Patients with SLE have a greater proportion of hypothyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of the possibility of thyroid dysfunction. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Self-avoiding walk on a square lattice with correlated vacancies

    Science.gov (United States)

    Cheraghalizadeh, J.; Najafi, M. N.; Mohammadzadeh, H.; Saber, A.

    2018-04-01

    The self-avoiding walk on the square site-diluted correlated percolation lattice is considered. The Ising model is employed to realize the spatial correlations of the metric space. As a well-accepted result, the (generalized) Flory's mean-field relation is tested to measure the effect of correlation. After exploring a perturbative Fokker-Planck-like equation, we apply an enriched Rosenbluth Monte Carlo method to study the problem. To be more precise, the winding angle analysis is also performed from which the diffusivity parameter of Schramm-Loewner evolution theory (κ ) is extracted. We find that at the critical Ising (host) system, the exponents are in agreement with Flory's approximation. For the off-critical Ising system, we find also a behavior for the fractal dimension of the walker trace in terms of the correlation length of the Ising system ξ (T ) , i.e., DFSAW(T ) -DFSAW(Tc) ˜1/√{ξ (T ) } .

  10. Ecole d’été de probabilités de Saint-Flour XXXII

    CERN Document Server

    2004-01-01

    This is yet another indispensable volume for all probabilists and collectors of the Saint-Flour series, and is also of great interest for mathematical physicists. It contains two of the three lecture courses given at the 32nd Probability Summer School in Saint-Flour (July 7-24, 2002). Boris Tsirelson's lectures introduce the notion of nonclassical noise produced by very nonlinear functions of many independent random variables, for instance singular stochastic flows or oriented percolation. Two examples are examined (noise made by a Poisson snake, the Brownian web). A new framework for the scaling limit is proposed, as well as old and new results about noises, stability, and spectral measures. Wendelin Werner's contribution gives a survey of results on conformal invariance, scaling limits and properties of some two-dimensional random curves. It provides a definition and properties of the Schramm-Loewner evolutions, computations (probabilities, critical exponents), the relation with critical exponents of planar...

  11. Simulated learning environment (SLE) in audiology education: A systematic review.

    Science.gov (United States)

    Dzulkarnain, Ahmad Aidil Arafat; Wan Mhd Pandi, Wan Mahirah; Rahmat, Sarah; Zakaria, Nur 'Azzah

    2015-01-01

    To systematically review the relevant peer-review literature investigating the outcome of simulated learning environment (SLE) training in audiology education. A systematic review research design. Fifteen databases were searched with four studies meeting the inclusion criteria. Three of the four studies revealed positive findings for the use of an SLE (that is, the SLE group showed a higher post-training score compared to the traditional training group or a significantly higher post-training score than the non-training groups). One study revealed negative findings where the traditional training group showed a significantly higher post-training score than the SLE group. In addition, both the studies comparing post- and pre-training scores reported significantly higher post-training scores than the pre-training scores of the participants that underwent SLE training. Overall, this review supports the notions that SLE training is an effective learning tool and can be used for basic clinical training. This conclusion should be treated with caution, considering the limited numbers of studies published in this area and future research should be conducted to cope with the gaps highlighted in this review.

  12. Multi-User Space Link Extension (SLE) System

    Science.gov (United States)

    Perkins, Toby

    2013-01-01

    The Multi-User Space (MUS) Link Extension system, a software and data system, provides Space Link Extension (SLE) users with three space data transfer services in timely, complete, and offline modes as applicable according to standards defined by the Consultative Committee for Space Data Systems (CCSDS). MUS radically reduces the schedule, cost, and risk of implementing a new SLE user system, minimizes operating costs with a lights-out approach to SLE, and is designed to require no sustaining engineering expense during its lifetime unless changes in the CCSDS SLE standards, combined with new provider implementations, force changes. No software modification to MUS needs to be made to support a new mission. Any systems engineer with Linux experience can begin testing SLE user service instances with MUS starting from a personal computer (PC) within five days. For flight operators, MUS provides a familiar-looking Web page for entering SLE configuration data received from SLE. Operators can also use the Web page to back up a space mission's entire set of up to approximately 500 SLE service instances in less than five seconds, or to restore or transfer from another system the same amount of data from a MUS backup file in about the same amount of time. Missions operate each MUS SLE service instance independently by sending it MUS directives, which are legible, plain ASCII strings. MUS directives are usually (but not necessarily) sent through a TCP-IP (Transmission Control Protocol Internet Protocol) socket from a MOC (Mission Operations Center) or POCC (Payload Operations Control Center) system, under scripted control, during "lights-out" spacecraft operation. MUS permits the flight operations team to configure independently each of its data interfaces; not only commands and telemetry, but also MUS status messages to the MOC. Interfaces can use single- or multiple-client TCP/IP server sockets, TCP/IP client sockets, temporary disk files, the system log, or standard in

  13. Immunomodulators in SLE: Clinical evidence and immunologic actions.

    Science.gov (United States)

    Durcan, L; Petri, M

    2016-11-01

    Systemic lupus erythematosus (SLE) is a potentially fatal autoimmune disease. Current treatment strategies rely heavily on corticosteroids, which are in turn responsible for a significant burden of morbidity, and immunosuppressives which are limited by suboptimal efficacy, increased infections and malignancies. There are significant deficiencies in our immunosuppressive armamentarium, making immunomodulatory therapies crucial, offering the opportunity to prevent disease flare and the subsequent accrual of damage. Currently available immunomodulators include prasterone (synthetic dehydroeipandrosterone), vitamin D, hydroxychloroquine and belimumab. These therapies, acting via numerous cellular and cytokine pathways, have been shown to modify the aberrant immune responses associated with SLE without overt immunosuppression. Vitamin D is important in SLE and supplementation appears to have a positive impact on disease activity particularly proteinuria. Belimumab has specific immunomodulatory properties and is an effective therapy in those with specific serological and clinical characteristics predictive of response. Hydroxychloroquine is a crucial background medication in SLE with actions in many molecular pathways. It has disease specific effects in reducing flare, treating cutaneous disease and inflammatory arthralgias in addition to other effects such as reduced thrombosis, increased longevity, improved lipids, better glycemic control and blood pressure. Dehydroeipandrosterone is also an immunomodulator in SLE which can have positive effects on disease activity and has bone protective properties. This review outlines the immunologic actions of these drugs and the clinical evidence supporting their use. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Baseline Retinal Examinations among SLE Patients Newly Initiating Hydroxychloroquine in a U.S. Medicaid SLE Population, 2000-2010.

    Science.gov (United States)

    Lin, Tzu-Chieh; Marmor, Michael F; Barbhaiya, Medha; Guan, Hongshu; Chen, Sarah K; Feldman, Candace H; Costenbader, Karen H

    2018-02-06

    Baseline retinal examination has long been recommended at hydroxychloroquine (HCQ) initiation, but it is unknown how well this guideline is followed. We investigated baseline eye examinations among U.S. Medicaid SLE patients initiating HCQ. Using billing codes, we identified SLE patients aged 18-65 enrolled in Medicaid, residing in the 29 most populated U.S. states from 2000-2010. New HCQ users were identified by filling a prescription, with none in the preceding 12 months. Baseline retinal exams were identified within 30 days before to one year after this index prescription. We examined proportions of patients receiving retinal exams over the study years and compared characteristics of those who did and did not receive exams using bivariable and multivariable logistic regression models. Of 12,755 SLE patients newly starting HCQ, 32.5% received baseline dilated eye exams. The proportions of individuals receiving baseline eye exams did not significantly change during these years (31.0% to 34.4%, p for trend 0.12). Factors associated with increased likelihood of examinations included female sex, Asian versus White race, and receiving a higher number of laboratory tests during the preceding year. Lower proportions of Black and Native American versus White SLE patients had baseline retinal exams. Only one third of Medicaid SLE patients newly initiating HCQ received recommended baseline retinal examinations and this proportion did not significantly increase during these years. The sociodemographic variation in this indicated care has been observed for other recommended medical care for SLE and requires both further investigation and interventions to address it. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  15. Cryptogenic Organising Pneumonia As The Initial Presenting Manifestation of SLE

    Directory of Open Access Journals (Sweden)

    Neena Mampilly

    2015-07-01

    Full Text Available Cryptogenic Organising Pneumonia (COP, also called idiopathic Bronchiolitis Obliterans Organising Pneumonia( BOOP, is a distinct entity among the idiopathic interstitial pneumonias defined histopathologically by intraalveolar buds of granulation tissue. The etiology includes idiopathic, infectious, drug induced radiation induced and connective tissue diseases. Organising pneumonia occurs particularly in patients with dermatomyositis-polymyositis where it may be the presenting manifestation, and rarely in SLE, rheumatoid arthritis, scleroderma and other connective tissue diseases. We describe a 30 yr old lady who initially presented with respiratory symptoms, not responding to antibiotics. She was subsequently diagnosed as SLE and HRCT thorax showed consolidation involving both lung fields. A percutaneous lung biopsy revealed features of Cryptogenic Organising Pneumonia.

  16. Independent association of glucocorticoids with damage accrual in SLE.

    Science.gov (United States)

    Apostolopoulos, Diane; Kandane-Rathnayake, Rangi; Raghunath, Sudha; Hoi, Alberta; Nikpour, Mandana; Morand, Eric F

    2016-01-01

    To determine factors associated with damage accrual in a prospective cohort of patients with SLE. Patients with SLE who attended the Lupus Clinic at Monash Health, Australia, between 2007 and 2013 were studied. Clinical variables included disease activity (Systemic Lupus Erythematosus Disease Activity Index-2K, SLEDAI-2K), time-adjusted mean SLEDAI, cumulative glucocorticoid dose and organ damage (Systemic Lupus International Collaborating Clinics Damage Index (SDI)). Multivariate logistic regression analyses were performed to identify factors associated with damage accrual. A total of 162 patients were observed over a median (IQR) 3.6 (2.0-4.7) years. Seventy-five per cent (n=121) of patients received glucocorticoids. Damage accrual was significantly more frequent in glucocorticoid-exposed patients (42% vs 15%, p<0.01). Higher glucocorticoid exposure was independently associated with overall damage accrual after controlling for factors including ethnicity and disease activity and was significant at time-adjusted mean doses above 4.42 mg prednisolone/day; the OR of damage accrual in patients in the highest quartile of cumulative glucocorticoid exposure was over 10. Glucocorticoid exposure was independently associated with damage accrual in glucocorticoid-related and non-glucocorticoid related domains of the SDI. Glucocorticoid use is independently associated with the accrual of damage in SLE, including in non-glucocorticoid related domains.

  17. RNA-Seq for enrichment and analysis of IRF5 transcript expression in SLE.

    Directory of Open Access Journals (Sweden)

    Rivka C Stone

    Full Text Available Polymorphisms in the interferon regulatory factor 5 (IRF5 gene have been consistently replicated and shown to confer risk for or protection from the development of systemic lupus erythematosus (SLE. IRF5 expression is significantly upregulated in SLE patients and upregulation associates with IRF5-SLE risk haplotypes. IRF5 alternative splicing has also been shown to be elevated in SLE patients. Given that human IRF5 exists as multiple alternatively spliced transcripts with distinct function(s, it is important to determine whether the IRF5 transcript profile expressed in healthy donor immune cells is different from that expressed in SLE patients. Moreover, it is not currently known whether an IRF5-SLE risk haplotype defines the profile of IRF5 transcripts expressed. Using standard molecular cloning techniques, we identified and isolated 14 new differentially spliced IRF5 transcript variants from purified monocytes of healthy donors and SLE patients to generate an IRF5 variant transcriptome. Next-generation sequencing was then used to perform in-depth and quantitative analysis of full-length IRF5 transcript expression in primary immune cells of SLE patients and healthy donors by next-generation sequencing. Evidence for additional alternatively spliced transcripts was obtained from de novo junction discovery. Data from these studies support the overall complexity of IRF5 alternative splicing in SLE. Results from next-generation sequencing correlated with cloning and gave similar abundance rankings in SLE patients thus supporting the use of this new technology for in-depth single gene transcript profiling. Results from this study provide the first proof that 1 SLE patients express an IRF5 transcript signature that is distinct from healthy donors, 2 an IRF5-SLE risk haplotype defines the top four most abundant IRF5 transcripts expressed in SLE patients, and 3 an IRF5 transcript signature enables clustering of SLE patients with the H2 risk haplotype.

  18. A framework for remission in SLE : Consensus findings from a large international task force on definitions of remission in SLE (DORIS)

    NARCIS (Netherlands)

    van Vollenhoven, Ronald F.; Voskuyl, Alexandre E.; Bertsias, George K.; Aranow, Cynthia; Aringer, Martin; Arnaud, Laurent; Askanase, Anca; Balazova, Petra; Bonfa, Eloisa; Bootsma, Hendrika; Boumpas, Dimitrios T.; Bruce, Ian N.; Cervera, Ricard; Clarke, Ann; Coney, Cindy; Costedoat-Chalumeau, Nathalie; Czirjak, Laszlo; Derksen, Ronald; Doria, Andrea; Doerner, Thomas; Fischer-Betz, Rebecca; Fritsch-Stork, Ruth; Gordon, Caroline; Graninger, Winfried; Gyori, Noemi; Houssiau, Frederic A.; Isenberg, David A.; Jacobsen, Soren; Jayne, David; Kuhn, Annegret; Le Guern, Veronique; Lerstrom, Kirsten; Levy, Roger; Machado-Ribeiro, Francinne; Mariette, Xavier; Missaykeh, Jamil; Morand, Eric; Mosca, Marta; Inanc, Murat; Navarra, Sandra; Neumann, Irmgard; Olesinska, Marzena; Petri, Michelle; Rahman, Anisur; Rekvig, Ole Petter; Rovensky, Jozef; Shoenfeld, Yehuda; Smolen, Josef S.; Tincani, Angela; Urowitz, Murray; van Leeuw, Bernadette; Vasconcelos, Carlos; Voss, Anne; Werth, Victoria P.; Zakharova, Helena; Zoma, Asad; Schneider, Matthias; Ward, Michael

    Objectives Treat-to-target recommendations have identified `remission' as a target in systemic lupus erythematosus (SLE), but recognise that there is no universally accepted definition for this. Therefore, we initiated a process to achieve consensus on potential definitions for remission in SLE.

  19. Dimension of the SLE Light Cone, the SLE Fan, and SLE_κ(ρ) for κ \\in (0,4) and ρ \\in \\big[{κ/2}-4,-2\\big

    Science.gov (United States)

    Miller, Jason

    2018-02-01

    Suppose that h is a Gaussian free field (GFF) on a planar domain. Fix {κ \\in (0,4)} . The {SLE_κ} light cone L {(θ)} of h with opening angle {θ \\in [0,π]} is the set of points reachable from a given boundary point by angle-varying flow lines of the (formal) vector field {e^{ih/χ}} , {χ = {2}/{√{κ}} - {√{κ}}/{2}} , with angles in [-{θ}/{2},{θ}/{2}]. We derive the Hausdorff dimension of L {(θ)} . If {θ =0} then L {(θ)} is an ordinary {SLE_{κ}} curve (with {κ 4} ). In these extremes, this leads to a new proof of the Hausdorff dimension formula for {SLE} . We also consider {SLE_κ(ρ)} processes, which were originally only defined for {ρ > - 2} , but which can also be defined for {ρ ≤ -2} using Lévy compensation. The range of an {SLE_κ(ρ)} is qualitatively different when {ρ ≤ -2} . In particular, these curves are self-intersecting for {κ fan is the same as that of ordinary {SLE_κ}.

  20. Murine Lupus Susceptibility Locus Sle2 Activates DNA-Reactive B Cells through Two Sub-Loci with Distinct Phenotypes

    Science.gov (United States)

    Zeumer, Leilani; Sang, Allison; Niu, Haitao; Morel, Laurence

    2010-01-01

    The NZM2410-derived Sle2 lupus susceptibility locus induces an abnormal B cell differentiation which most prominently leads to the expansion of autoreactive B1a cells. We have mapped the expansion of B1a cells to three Sle2 sub-loci, Sle2a, Sle2b, and Sle2c. Sle2 also enhances the breach of B cell tolerance to nuclear antigens in the 56R anti-DNA immunoglobulin transgenic (Tg) model. This study used the Sle2 sub-congenic strains to map the activation of 56R Tg B cells. Sle2c strongly sustained the breach of tolerance and the activation of anti-DNA B cells. The production of Tg-encoded anti-DNA antibodies was more modest in Sle2a expressing mice, but Sle2a was responsible for the recruitment for Tg B cells to the marginal zone, a phenotype that has been found for 56R Tg B cells in mice expressing the whole Sle2 interval. In addition, Sle2a promoted the production of endogenously encoded anti-DNA antibodies. Overall, this study showed that at least two Sle2 genes are involved in the activation of anti-DNA B cells, and excluded more than two-thirds of the Sle2 interval from contributing to this phenotype. This constitutes an important step toward the identification of novel genes that play a critical role in B cell tolerance. PMID:21270826

  1. Simultaneous presentation of acute disseminated encephalomyelitis (ADEM) and systemic lupus erythematosus (SLE) after enteroviral infection: can ADEM present as the first manifestation of SLE?

    Science.gov (United States)

    Kim, J-M; Son, C-N; Chang, H W; Kim, S-H

    2015-05-01

    Central Nervous System (CNS) involvement of Systemic Lupus Erythematosus (SLE) includes a broad range of neuropsychiatric syndromes. Acute Disseminated Encephalomyelitis (ADEM) is a demyelinating CNS disorder characterized by encephalopathy and multifocal lesions predominantly involving the white matter on brain magnetic resonance imaging. ADEM associated with SLE has been only rarely reported. We report an unusual case of a 17-year-old girl who developed ADEM after enteroviral infection as the first manifestation of SLE. The authors emphasize that the patient's illness was preceded by enteroviral infection and that ADEM occurred before any other symptoms of SLE, which makes this case unique. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  2. Study on the brain CT scan of SLE patients

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, S; Narita, M; Katoh, K; Matsunaga, K; Ishigatsubo, Y [Yokohama City Univ. (Japan). Faculty of Medicine

    1982-03-01

    Cranial CT scanning revealed abnormality in 12 of 25 patients with SLE (48%). Ventricular sulcal enlargement was found mostly in younger patients between 16 and 36 years, an average of 25 years. Abnormality in electroencephalogram, principally paroxysmal abnormality, was found in 8 of 13 cases (62%) of normal CT findings. Non-paroxysmal slow-wave abnormality was observed in 9 of 12 abnormal CT cases. Of 13 patients with CNS symptoms, 8 had abnormal CT findings, and 5 had only mental disorder with normal CT findings. In 12 patients without neuropsychiatric involvement, 4 (33%) had abnormal CT findings. The rate of abnormal CT findings was increased in the patients receiving a high dosage of a steroid agent. Five of 6 patients who showed ventricular sulcal enlargement had been given prednisolone in a dosage of 35 mg or more per day.

  3. Hyperthyroidism association with SLE, lessons from real-life data--A case-control study.

    Science.gov (United States)

    Watad, Abdulla; Cohen, Arnon D; Comaneshter, Doron; Tekes-Manova, Dorit; Amital, Howard

    2016-01-01

    Despite the frequently encountered association between thyroid disease and systemic lupus erythematosus (SLE) is well known, it is of surprise that only several reports compromised of small population size support this observation. To investigate the association of comorbid SLE and hyperthyroidism. Using the database of the largest health maintenance organization (HMO) in Israel, the Clalit Health Services, we searched for the co-existence of SLE and hyperthyroidism. Patients with SLE were compared with age- and sex-matched controls regarding the prevalence of hyperthyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study included 5018 patients with SLE and 25,090 age- and sex- matched controls. The prevalence of hyperthyroidism in patients with SLE was increased compared with the prevalence in controls (2.59% and 0.91%, respectively, p hyperthyroidism (odds ratio 2.52, 95% confidence interval 2.028-3.137). Patients with SLE have a greater prevalence of hyperthyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of this possibility of this thyroid dysfunction.

  4. Complement-mediated solubilization of immune complexes. Solubilization inhibition and complement factor levels in SLE patients

    DEFF Research Database (Denmark)

    Baatrup, Gunnar; Petersen, Ivan; Kappelgaard, E

    1984-01-01

    Thirty-two of 36 serum samples from 19 SLE patients showed reduced capacity to mediate complement-dependent solubilization of immune complexes (IC). SLE patients with nephritis exerted the lowest complement-mediated solubilization capacity (CMSC) whereas sera from patients with inactive disease g...

  5. Pathogenic and Epiphenomenal Anti-DNA Antibodies in SLE

    Directory of Open Access Journals (Sweden)

    Mirjana Pavlovic

    2010-01-01

    Full Text Available The discoveries of natural and the development of manufactured highly efficient catalytic antibodies (abzymes opens the door to many practical applications. One of the most fascinating is the use of such antibodies in human therapy and prevention (vaccination, of cancer, AIDS, autoimmune diseases. A special entity of naturally occurring DNA hydrolytic anti-DNA antibodies is emerging within past decades linked to autoimmune and lymphoproliferative disorders, such as systemic lupus erythematosus (SLE, multiple sclerosis (MS, Sjogren Syndrome (SS, B - Chronic lymphocytic leucosis (B-CLL, and Multiple Myeloma (MM. The origin of the antibodies is unknown. The underlying mechanisms of these activities are suggested to be penetration into the living cells and translocation in the nucleus, with recognition of the specific binding sites at particular (ss or ds DNA. There are controversies in the literature whether hydrolysis is a sequence-specific event. The interplay between anti-DNA antibodies and DNA is not yet elucidated. This molecular “twist” also suggests that anti-DNA antibodies with DNA hydrolytic capacity could be the organism's immune response to a microbial attack, with microbial DNA, or specific genes within microbial DNA sequence, as a target for neutralization. The catalytic antibody-based approach can become a key tool in selective chemotherapeutic strategies.

  6. Disease activity assessment in SLE: do we have the right instruments?

    OpenAIRE

    Petri, Michelle

    2007-01-01

    No new therapy has been approved for systemic lupus erythematosus (SLE) in decades. Interest in SLE by pharmaceutical and biotechnology companies has increased, leading to multiple clinical trials. Unfortunately, we have now compiled quite a long list of “failed” trials. If this was due to the fact that the studied therapy did not work in SLE, we could accept it and move on. Of concern, however, is that many of the “failed” treatments had a strong “signal” of efficacy, often in subgroup analy...

  7. Study on the relationship between SLE and the related serum hormone

    International Nuclear Information System (INIS)

    Lu Yun; Deng Shouzhen; Lin Xiangtong; Feng Shufang; Xu Jinhua; He Wanting; Zhang Guangming; Cheng Wei; Gao Quan

    1998-01-01

    To explore the relationship between PRL, GH(RIA), GH(RRA) serum levels changes and the onset and development of disease in patients with SLE, and to understand the hormonal changes in active and inactive phase of disease, 28 cases and 20 controls were studied. The results showed that anti-ds-DNA serum level in active and inactive phases was higher than those in controls (P 1 2 <0.05). This study indicated that the higher serum level of PRL, GH(RIA), GH(RRA) is correlated with some autoimmune characteristics of SLE, especially in its active phase. Therefore it gives some help for clinical study of SLE

  8. Clinical and immunological aspects and outcome of a Brazilian cohort of 414 patients with systemic lupus erythematosus (SLE): comparison between childhood-onset, adult-onset, and late-onset SLE.

    Science.gov (United States)

    das Chagas Medeiros, M M; Bezerra, M Campos; Braga, F N Holanda Ferreira; da Justa Feijão, M R Melo; Gois, A C Rodrigues; Rebouças, V C do Rosário; de Carvalho, T M Amorim Zaranza; Carvalho, L N Solon; Ribeiro, Át Mendes

    2016-04-01

    The clinical expression of systemic lupus erythematosus (SLE) is influenced by genetic and environmental factors and therefore varies between ethnicities. Information on the epidemiology of SLE in Brazil is scarce and practically limited to studies conducted in socioeconomically developed regions (South and Southeast). The objective of this study was to describe the clinical and immunological aspects and outcome of a cohort of patients with SLE treated at a university hospital in northeastern Brazil and compare patterns related to age at onset: childhood (cSLE), adult (aSLE), and late (lSLE). A random sample of 414 records (women: 93.5%) were reviewed. The mean age at SLE onset and the mean disease duration were 28.9 ± 10.9 years and 10.2 ± 6.6 years, respectively. Most patients had aSLE (n = 338; 81.6%), followed by cSLE (n = 60; 14.5%) and lSLE (n = 16; 3.9%). The female/male ratio was 6.5:1 in cSLE and 16.8:1 in aSLE; in lSLE, all patients were female (p = 0.05). During follow-up, the cSLE group presented higher rates of nephritis (70% vs. 52.9% vs. 12.5%; p = 0.0001) and leuko/lymphopenia (61.7% vs. 43.8% vs. 56.2%; p = 0.02). No significant differences were found for anti-dsDNA, anti-Sm, and antiphospholipid antibodies. Treatment with immunosuppressants was significantly more common, and higher doses of prednisone were used, in cSLE. The prevalence of cardiovascular diseases were more frequent in lSLE (p = 0.03). No significant differences were found between the three groups with regard to mean damage accrual (SDI), remission, and mortality. Although cSLE presented higher rates of nephritis and leuko/lymphopenia, more frequent use of immunosuppressants and higher prednisone doses than aSLE and lSLE, the three groups did not differ significantly with regard to damage accrual, remission, and mortality. © The Author(s) 2015.

  9. Functional promoter haplotypes of the human FAS gene are associated with the phenotype of SLE characterized by thrombocytopenia

    DEFF Research Database (Denmark)

    Nolsøe, R L; Kelly, J A; Pociot, F

    2005-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by production of autoantibodies against intracellular antigens and tissue injury. Defective apoptosis of activated immune cells leads to the development of autoantibodies in SLE. FasL initiated apoptosis is central...... for peripheral tolerance. Fas deficiencies in humans and mice predispose toward systemic autoimmunity. SLE is conferred by many genes. The genetic effects may be concentrated by familial clustering or by stratifying of subphenotypes. We have tested polymorphisms and haplotypes in FAS and FASL for association...... to SLE or subphenotypes in 126 multiplex American SLE pedigrees and found association of the FAS codon214 AC(C/T) as well as the FAS-670G>A'-codon214 AC(C/T)' haplotype to thrombocytopenia in SLE. Furthermore we have functionally characterized the FAS/FASL promoter polymorphisms associated with SLE...

  10. Site differences in mild cognitive dysfunction (MCD) among patients with systemic lupus erythematosus (SLE).

    Science.gov (United States)

    Kozora, E; Erkan, D; West, S G; Filley, C M; Zhang, L; Ramon, G; Duggan, E; Lockshin, M D

    2013-01-01

    Mild cognitive dysfunction (MCD) is common in patients with systemic lupus erythematosus (MCD-SLE) but few studies have investigated potential site differences. SLE patients from Denver, CO, and New York, NY, were enrolled in two different cognition studies employing similar screening methods. Using the resulting neuropsychological scores, cognitive impairment was calculated using a cognitive impairment index (CII). The rate of MCD-SLE was 24% at the Denver, CO, site and 60% at the New York, NY, site. The mean CII was 2.6 ± 2.3 versus 4.4 ± 2.7, respectively (p = 0.005). The NY participants had a significantly longer disease duration (p = 0.13) and higher American College of Rheumatology SLE criteria scores (p > 0.001). NY participants had a higher frequency of impairment in semantic verbal fluency (p = 0.005), visuomotor speed (p = 0.013), and motor sequencing (p = 0.001). A correlation was found between cognitive impairment and SLE disease duration (p = 0.03). The rate of MCD-SLE was greater in SLE patients from New York, NY, compared to patients in the Denver, CO, area. The greater duration of disease and higher prevalence of medical complications in the NY group might contribute to this difference. Findings suggest that MCD-SLE may differ by site, but future studies that better evaluate site or selection bias are recommended.

  11. Space Link Extension (SLE) Emulation for High-Throughput Network Communication

    Science.gov (United States)

    Murawski, Robert W.; Tchorowski, Nicole; Golden, Bert

    2014-01-01

    As the data rate requirements for space communications increases, significant stress is placed not only on the wireless satellite communication links, but also on the ground networks which forward data from end-users to remote ground stations. These wide area network (WAN) connections add delay and jitter to the end-to-end satellite communication link, effects which can have significant impacts on the wireless communication link. It is imperative that any ground communication protocol can react to these effects such that the ground network does not become a bottleneck in the communication path to the satellite. In this paper, we present our SCENIC Emulation Lab testbed which was developed to test the CCSDS SLE protocol implementations proposed for use on future NASA communication networks. Our results show that in the presence of realistic levels of network delay, high-throughput SLE communication links can experience significant data rate throttling. Based on our observations, we present some insight into why this data throttling happens, and trace the probable issue back to non-optimal blocking communication which is sup-ported by the CCSDS SLE API recommended practices. These issues were presented as well to the SLE implementation developers which, based on our reports, developed a new release for SLE which we show fixes the SLE blocking issue and greatly improves the protocol throughput. In this paper, we also discuss future developments for our end-to-end emulation lab and how these improvements can be used to develop and test future space communication technologies.

  12. Immunomodulatory Effect of Agave tequilana Evaluated on an Autoimmunity Like-SLE Model Induced in Balb/c Mice with Pristane.

    Science.gov (United States)

    Gutiérrez Nava, Zúlima Jannette; Jiménez-Aparicio, Antonio Ruperto; Herrera-Ruiz, Maribel Lucila; Jiménez-Ferrer, Enrique

    2017-05-25

    In this work, the immunomodulatory activity of the acetone extract and the fructans obtained from Agave tequilana were evaluated, on the systemic autoimmunity type-SLE model generated by the administration of 2,6,10,14-tetramethylpentadecane (TMPD, also known as pristane) on Balb/c female mice. The systemic autoimmunity type-SLE was observed seven months after the application of TMPD, in which the animals from the negative control group (animals with damage and without any other treatment) developed articular inflammation, proteinuria, an increment of the antinuclear antibody titters and tissue pro-inflammatory cytokines levels (IL-1β, IL-6, TNF-α e IFN-γ) as well as the anti-inflammatory cytokine IL-10. The administration of the different treatments and the extracts of A. tequilana , provoked the decrease of: articular inflammation, the development of proteinuria, ssDNA/dsDNA antinuclear antibody titters and cytokines IL-1β, IL-6, TNF-α, IFN-γ and IL-10. The phytochemical analysis of the acetone extract identified the presence of the following compounds: β-sitosterol glycoside; 3,7,11,15-tetramethyl-2-hexadecen-1-ol (phytol); octadecadienoic acid-2,3-dihydroxypropyl ester; stigmasta-3,5-dien-7-one; cycloartenone and cycloartenol. Therefore, A. tequilana contains active compounds with the capacity to modify the evolution of the systemic autoimmunity type-SLE on a murine model.

  13. Immunomodulatory Effect of Agave tequilana Evaluated on an Autoimmunity Like-SLE Model Induced in Balb/c Mice with Pristane

    Directory of Open Access Journals (Sweden)

    Zúlima Jannette Gutiérrez Nava

    2017-05-01

    Full Text Available In this work, the immunomodulatory activity of the acetone extract and the fructans obtained from Agave tequilana were evaluated, on the systemic autoimmunity type-SLE model generated by the administration of 2,6,10,14-tetramethylpentadecane (TMPD, also known as pristane on Balb/c female mice. The systemic autoimmunity type-SLE was observed seven months after the application of TMPD, in which the animals from the negative control group (animals with damage and without any other treatment developed articular inflammation, proteinuria, an increment of the antinuclear antibody titters and tissue pro-inflammatory cytokines levels (IL-1β, IL-6, TNF-α e IFN-γ as well as the anti-inflammatory cytokine IL-10. The administration of the different treatments and the extracts of A. tequilana, provoked the decrease of: articular inflammation, the development of proteinuria, ssDNA/dsDNA antinuclear antibody titters and cytokines IL-1β, IL-6, TNF-α, IFN-γ and IL-10. The phytochemical analysis of the acetone extract identified the presence of the following compounds: β-sitosterol glycoside; 3,7,11,15-tetramethyl-2-hexadecen-1-ol (phytol; octadecadienoic acid-2,3-dihydroxypropyl ester; stigmasta-3,5-dien-7-one; cycloartenone and cycloartenol. Therefore, A. tequilana contains active compounds with the capacity to modify the evolution of the systemic autoimmunity type-SLE on a murine model.

  14. Clinical significance of changes of expression of anti-dsDNA antibody in serum in patients with SLE

    International Nuclear Information System (INIS)

    Chen Xingguo; Zhang Xiaoli; Liu Chunyan; Cao Jiwei; Du Tongxing; Wang Zizheng

    2008-01-01

    Objective: To investigate the significance of anti-dsDNA antibody in diagnosis and treatment of SLE through measurement of changes of serum anti-dsDNA antibody expression in patients with SLE. Methods: Serum anti-dsDNA antibody was detected with radioisotope method in 60 patients with SLE and 33 controls (consisted of patients with other collagen diseases including Sjogren syndrome, systemic sclerosis, rheumatoid arthritis, polymyositis, mixed connective tissue disease, ankylosing spondylitis). Clinical manifestation and laboratory findings in the SLE patients were studied in detail. Results: (1) Serum anti-dsDNA antibody was positive in 39 of the 60 SLE patients with only two false positive cases in the 33 controls: a sensitivity of 65% and specificity of 93. 3%. (2) In SLE patients, positivity of anti-dsDNA antibody was not correlated with positivity of anti-Sm antibody (P>0.05), but was correlated with positivity of anti-SSA antibody (P<0.05). (3) Incidences of alopecia, skin rashes, oral mucosal ulcer, proteinuria were significantly higher in SLE patients with positive anti-dsDNA antibody than those in SLE patients with negative anti-dsDNA antibody (P<0.05). (4) Incidences of leukopenia and thrombocytopenia were also significantly higher in SLE patients with positive anti-dsDNA antibody (P<0.05). Conclusion: Anti-dsDNA antibody could be taken as a specific marker of SLE and the serum expression were positively correlated with the activity and severity of the disease. (authors)

  15. The STAT4 SLE risk allele rs7574865[T] is associated with increased IL-12-induced IFN-γ production in T cells from patients with SLE.

    Science.gov (United States)

    Hagberg, Niklas; Joelsson, Martin; Leonard, Dag; Reid, Sarah; Eloranta, Maija-Leena; Mo, John; Nilsson, Magnus K; Syvänen, Ann-Christine; Bryceson, Yenan T; Rönnblom, Lars

    2018-02-23

    Genetic variants in the transcription factor STAT4 are associated with increased susceptibility to systemic lupus erythematosus (SLE) and a more severe disease phenotype. This study aimed to clarify how the SLE-associated intronic STAT4 risk allele rs7574865[T] affects the function of immune cells in SLE. Peripheral blood mononuclear cells (PBMCs) were isolated from 52 genotyped patients with SLE. Phosphorylation of STAT4 (pSTAT4) and STAT1 (pSTAT1) in response to interferon (IFN)-α, IFN-γ or interleukin (IL)-12, total levels of STAT4, STAT1 and T-bet, and frequency of IFN-γ + cells on IL-12 stimulation were determined by flow cytometry in subsets of immune cells before and after preactivation of cells with phytohaemagglutinin (PHA) and IL-2. Cellular responses and phenotypes were correlated to STAT4 risk allele carriership. Janus kinase inhibitors (JAKi) selective for TYK2 (TYK2i) or JAK2 (JAK2i) were evaluated for inhibition of IL-12 or IFN-γ-induced activation of SLE PBMCs. In resting PBMCs, the STAT4 risk allele was neither associated with total levels of STAT4 or STAT1, nor cytokine-induced pSTAT4 or pSTAT1. Following PHA/IL-2 activation, CD8 + T cells from STAT4 risk allele carriers displayed increased levels of STAT4 resulting in increased pSTAT4 in response to IL-12 and IFN-α, and an augmented IL-12-induced IFN-γ production in CD8 + and CD4 + T cells. The TYK2i and the JAK2i efficiently blocked IL-12 and IFN-γ-induced activation of PBMCs from STAT4 risk patients, respectively. T cells from patients with SLE carrying the STAT4 risk allele rs7574865[T] display an augmented response to IL-12 and IFN-α. This subset of patients may benefit from JAKi treatment. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Barriers And Motivators for Smoking Cessation in Patients With Systemic Lupus Erythematosus (SLE).

    Science.gov (United States)

    Terrell, Deirdra R; Stewart, Lauren M; Tolma, Eleni L; McClain, Rebekah; Vesely, Sara K; James, Judith A

    2015-11-01

    Although studies have shown that smoking is detrimental to the health of patients with systemic lupus erythematosus (SLE), studies regarding barriers and motivators for smoking cessation are lacking. The purpose of this study was to generate hypotheses regarding the barriers and motivators for smoking cessation in SLE patients. This study was based on the theoretical framework of the stages of change model. All participants met SLE classification criteria. Interviews were conducted with 16 current and 10 former smokers. Motivators included: medical reasons, readiness, and concern for others. Barriers included: enjoyment, coping mechanism, and an emotional connection. Participants were unsure of the impact of smoking on their medication and disease, and had mixed feelings regarding the impact on pain. The main motivator for cessation in this population was concern for one's health. Rheumatologists need to include disease specific harms and assess pain management strategies as part of cessation counseling.

  17. Diagnostic significance of the radiologic appearances of the hands in systemic lupus erythematosus (SLE)

    Energy Technology Data Exchange (ETDEWEB)

    Winkler, P; Baenkler, H W; Pfuhl, E; Gutmann, W

    1980-09-01

    40 patients with SLE were assessed, the diagnoses being made according to modified ARA-criteria; the hand films of 25 of these patients were analysed. The most important roentgenologic findings consisted of reducible deformities with mild or absent articular changes in the deformed MCP and PIP joints. As these changes often occur late in the course of SLE, a primary radiological diagnosis was possible in only three cases (8%), whereas hand films provided confirmatory evidence of disease in a further seven patients. These roentgenological characteristics of SLE were found significantly less often in patients with definite RA; this group tended to have positive ANF (antinuclear factors). Antibodies against DNA may be absent, especially in a less active phase of disease. ANF is non-specific, and SLE simulates RA in 10-20% of cases. It is, therefore, very important in individual cases to consider the diagnosis of SLE in the presence of deformity without corresponding articular changes. Direct comparison of both the p.a. and oblique views is essential in the evaluation of reducible deformities, although this point has not been stressed in the literature. Reducible deformities may be overlooked in physical examination, when the patient gives no history of functional disability. The main differential diagnosis is Jaccoud's arthropathy, which is rarely seen in a general hospital. Most of these patients give a history of recurrent rheumatic fever, a minority complain about joint pain or disability, approximately 90% show signs indicating a valvular lesion of the heart, over 75% have a normal ESR and a positive rheumatoid or antinuclear factor is very rarely found. The distinction from SLE or rheumatoid arthritis is therefore easily established on additional non-radiological criteria.

  18. The diagnostic significance of the radiologic appearances of the hands in systemic lupus erythematosus (SLE)

    International Nuclear Information System (INIS)

    Winkler, P.; Baenkler, H.W.; Pfuhl, E.; Gutmann, W.

    1980-01-01

    40 patients with SLE were assessed, the diagnoses being made according to modified ARA-criteria; the hand films of 25 of these patients were analysed. The most important roentgenologic findings consisted of reducible deformities with mild or absent articular changes in the deformed MCP and PIP joints. As these changes often occur late in the course of SLE, a primary radiological diagnosis was possible in only three cases (8%), whereas hand films provided confirmatory evidence of disease in a further seven patients. These roentgenological characteristics of SLE were found significantly less often in patients with definite RA; this group tended to have positive ANF (antinuclear factors). Antibodies against DNA may be absent, especially in a less active phase of disease. ANF is non-specific, and SLE simulates RA in 10-20% of cases. It is, therefore, very important in individual cases to consider the diagnosis of SLE in the presence of deformity without corresponding articular changes. Direct comparison of both the p.a. and oblique views is essential in the evaluation of reducible deformities, although this point has not been stressed in the literature. Reducible deformities may be overlooked in physical examination, when the patient gives no history of functional disability. The main differential diagnosis is Jaccoud's arthropathy, which is rarely seen in a general hospital. Most of these patients give a history of recurrent rheumatic fever, a minority complain about joint pain or disability, approximately 90% show signs indicating a valvular lesion of the heart, over 75% have a normal ESR and a positive rheumatoid or antinuclear factor is very rarely found. The distinction from SLE or rheumatoid arthritis is therefore easily established on additional non-radiological criteria. (orig./MG) [de

  19. Surface complement C3 fragments and cellular binding of microparticles in patients with SLE

    DEFF Research Database (Denmark)

    Winberg, Line Kjær; Nielsen, Claus Henrik; Jacobsen, Søren

    2017-01-01

    Objectives: To examine microparticles (MPs) from patients with SLE and healthy controls (HCs) by determining the cellular origin of the MPs, quantifying attached fragments of complement component 3 (C3) and assessing the ability of MPs to bind to circulating phagocytes and erythrocytes. These fea......Objectives: To examine microparticles (MPs) from patients with SLE and healthy controls (HCs) by determining the cellular origin of the MPs, quantifying attached fragments of complement component 3 (C3) and assessing the ability of MPs to bind to circulating phagocytes and erythrocytes...

  20. A framework for remission in SLE: consensus findings from a large international task force on definitions of remission in SLE (DORIS).

    Science.gov (United States)

    van Vollenhoven, Ronald; Voskuyl, Alexandre; Bertsias, George; Aranow, Cynthia; Aringer, Martin; Arnaud, Laurent; Askanase, Anca; Balážová, Petra; Bonfa, Eloisa; Bootsma, Hendrika; Boumpas, Dimitrios; Bruce, Ian; Cervera, Ricard; Clarke, Ann; Coney, Cindy; Costedoat-Chalumeau, Nathalie; Czirják, László; Derksen, Ronald; Doria, Andrea; Dörner, Thomas; Fischer-Betz, Rebecca; Fritsch-Stork, Ruth; Gordon, Caroline; Graninger, Winfried; Györi, Noémi; Houssiau, Frédéric; Isenberg, David; Jacobsen, Soren; Jayne, David; Kuhn, Annegret; Le Guern, Veronique; Lerstrøm, Kirsten; Levy, Roger; Machado-Ribeiro, Francinne; Mariette, Xavier; Missaykeh, Jamil; Morand, Eric; Mosca, Marta; Inanc, Murat; Navarra, Sandra; Neumann, Irmgard; Olesinska, Marzena; Petri, Michelle; Rahman, Anisur; Rekvig, Ole Petter; Rovensky, Jozef; Shoenfeld, Yehuda; Smolen, Josef; Tincani, Angela; Urowitz, Murray; van Leeuw, Bernadette; Vasconcelos, Carlos; Voss, Anne; Werth, Victoria P; Zakharova, Helena; Zoma, Asad; Schneider, Matthias; Ward, Michael

    2017-03-01

    Treat-to-target recommendations have identified 'remission' as a target in systemic lupus erythematosus (SLE), but recognise that there is no universally accepted definition for this. Therefore, we initiated a process to achieve consensus on potential definitions for remission in SLE. An international task force of 60 specialists and patient representatives participated in preparatory exercises, a face-to-face meeting and follow-up electronic voting. The level for agreement was set at 90%. The task force agreed on eight key statements regarding remission in SLE and three principles to guide the further development of remission definitions:1. Definitions of remission will be worded as follows: remission in SLE is a durable state characterised by …………………. (reference to symptoms, signs, routine labs).2. For defining remission, a validated index must be used, for example, clinical systemic lupus erythematosus disease activity index (SLEDAI)=0, British Isles lupus assessment group (BILAG) 2004 D/E only, clinical European consensus lupus outcome measure (ECLAM)=0; with routine laboratory assessments included, and supplemented with physician's global assessment.3. Distinction is made between remission off and on therapy: remission off therapy requires the patient to be on no other treatment for SLE than maintenance antimalarials; and remission on therapy allows patients to be on stable maintenance antimalarials, low-dose corticosteroids (prednisone ≤5 mg/day), maintenance immunosuppressives and/or maintenance biologics.The task force also agreed that the most appropriate outcomes (dependent variables) for testing the prognostic value (construct validity) of potential remission definitions are: death, damage, flares and measures of health-related quality of life. The work of this international task force provides a framework for testing different definitions of remission against long-term outcomes. Published by the BMJ Publishing Group Limited. For

  1. Multiple Autoantibodies Display Association with Lymphopenia, Proteinuria, and Cellular Casts in a Large, Ethnically Diverse SLE Patient Cohort

    Directory of Open Access Journals (Sweden)

    Rufei Lu

    2012-01-01

    Full Text Available Purpose. This study evaluates high-throughput autoantibody screening and determines associated systemic lupus erythematosus (SLE clinical features in a large lupus cohort. Methods. Clinical and demographic information, along with serum samples, were obtained from each SLE study participant after appropriate informed consent. Serum samples were screened for 10 distinct SLE autoantibody specificities and examined for association with SLE ACR criteria and subcriteria using conditional logistic regression analysis. Results. In European-American SLE patients, autoantibodies against 52 kD Ro and RNP 68 are independently enriched in patients with lymphopenia, anti-La, and anti-ribosomal P are increased in patients with malar rash, and anti-dsDNA and anti-Sm are enriched in patients with proteinuria. In African-American SLE patients, cellular casts associate with autoantibodies against dsDNA, Sm, and Sm/nRNP. Conclusion. Using a high-throughput, bead-based method of autoantibody detection, anti-dsDNA is significantly enriched in patienets with SLE ACR renal criteria as has been previously described. However, lymphopenia is associated with several distinct autoantibody specificities. These findings offer meaningful information to allow clinicians and clinical investigators to understand which autoantibodies correlate with select SLE clinical manifestations across common racial groups using this novel methodology which is expanding in clinical use.

  2. Women's experience of SLE-related fatigue: a focus group interview study.

    Science.gov (United States)

    Pettersson, Susanne; Möller, Sonia; Svenungsson, Elisabet; Gunnarsson, Iva; Welin Henriksson, Elisabet

    2010-10-01

    The aim of this study was to describe women's experience of SLE-related fatigue, how they express the feeling of fatigue, impact on life and strategies developed to manage fatigue in daily living. Seven, semi-structured focus group discussions with 33 women were audio-taped, transcribed verbatim and analysed according to qualitative content analysis. Perceptions of SLE-related fatigue were sorted into four themes. Nature of Fatigue, involved the sensation, occurrence and character. Aspects Affected by Fatigue described emotions that arose together with fatigue as well as aspects of work, family life, social contacts and leisure activities that were affected by fatigue. Striving Towards Power and Control concluded the array of ways used to manage daily life and were categorized into the mental struggle, structure, restrict and provide. Factors Influencing the Perception of Fatigue described understanding from their surroundings and pain as strongly influencing the experience and perception of fatigue. SLE-related fatigue was portrayed as an overwhelming phenomenon with an unpredictable character, resulting in the feeling that fatigue dominates and controls most situations in life. The choice of strategies was described as a balance with implications for how fatigue limited a person's life. Health care professionals are advised to take a more active role to empower people with SLE to find their own balance as a way to achieve a feeling of being in control.

  3. Endovascular repair as a sole treatment in multiple aneurysms in patient with SLE

    International Nuclear Information System (INIS)

    Dineva, S.; Al-Amin, M.; Demetriou, S.; Tsetis, D.

    2013-01-01

    Full text: Introduction: Most aneurysms are local manifestations of systemic disease. For patients over 65 years the incidence of aneurysm of the abdominal aorta (AAA) is approximately 5-6% in men and 1-2 % for women. The presence of both the AAA and aneurysms in other location is even rarer, and this percentage is likely increase further in patients with systemic lupus erythematosus (SLE). What you will learn: We present a rare clinical case of endovascular treatment of multifocal aneurysm including post catheterization pseudoaneurysm. The patient is a 73 years old woman with a history of SLE and age-related comorbidity. Originally an endovascular treatment of aneurysms of the abdominal aorta and right common iliac artery was used. Two years later a successfully endovascular treatment of aneurysm of the right renal artery was conducted, which however is complicated by the formation of a pseudoaneurysm in access through the left femoral artery. The late one is again treated endovascular by placement of a covered stent after failure of percutaneous injection of 1000 UI thrombin. Discussion: Adult patients with a long history of SLE are unsuitable candidates for surgical treatment of aneurysmal disease, especially in its multifocal form. In our case we have taken multistep successful endovascular procedures, including technically hard placing of the stent at the site of the right renal aneurysms, and post catheterization pseudoaneurysm. Conclusion: Multifocal aneurysmal vascular changes due to macroangiopathia in SLE can be treated alone by endovascular means in multi-stages procedures

  4. Autoantibodies against Modified Histone Peptides in SLE Patients Are Associated with Disease Activity and Lupus Nephritis

    NARCIS (Netherlands)

    Dieker, J.W.; Berden, J.H.; Bakker, M.A.; Briand, J.P.; Muller, S.; Voll, R.; Sjowall, C.; Herrmann, M.; Hilbrands, L.B.; Vlag, J. van der

    2016-01-01

    Persistent exposure of the immune system to death cell debris leads to autoantibodies against chromatin in patients with systemic lupus erythematosus (SLE). Deposition of anti-chromatin/chromatin complexes can instigate inflammation in multiple organs including the kidney. Previously we identified

  5. The useful application of anti-ds DNA antibody radioimmunoassay in the diagnosis of male SLE patients

    International Nuclear Information System (INIS)

    Alshaikhly, A.W.A.R.

    1995-01-01

    From the period of 1994 to 1990, the anti double stranded deoxyribonucleic acid radioimmunoassay (Anti-ds DNA RIA) were extensively applied to confirm diagnosis of Systemic Lupus Erythematosus (SLE) disease in male patients. 54 patients sera with definite diagnosis of SLE, 30 patients sera with Rheumatoid Arthritis (RA), 20 patients sera with other Rheumatic or Collagen vascular diseases (ORD), 5 patients sera of non specific arthritis (NSA) and 55 healthy male individual sera were included. The 54 male SLE patients were diagnosed after screening more than 2000 sera from male patients with various Rheumatic diseases who overlapping clinical symptoms with SLE. The results of this study are confirming that the anti-ds DNA RIA is proved to be a simple, sensitive, specific and useful technique among various assays used for diagnosis purposes. The results also pointed out that the prevalence of SLE disease in males is much lower than females. 4 tabs

  6. The useful application of anti-ds DNA antibody radioimmunoassay in the diagnosis of male SLE patients

    Energy Technology Data Exchange (ETDEWEB)

    Alshaikhly, A W.A.R. [Al-Rasheed Hospital, Baghdad, (Iraq)

    1995-10-01

    From the period of 1994 to 1990, the anti double stranded deoxyribonucleic acid radioimmunoassay (Anti-ds DNA RIA) were extensively applied to confirm diagnosis of Systemic Lupus Erythematosus (SLE) disease in male patients. 54 patients sera with definite diagnosis of SLE, 30 patients sera with Rheumatoid Arthritis (RA), 20 patients sera with other Rheumatic or Collagen vascular diseases (ORD), 5 patients sera of non specific arthritis (NSA) and 55 healthy male individual sera were included. The 54 male SLE patients were diagnosed after screening more than 2000 sera from male patients with various Rheumatic diseases who overlapping clinical symptoms with SLE. The results of this study are confirming that the anti-ds DNA RIA is proved to be a simple, sensitive, specific and useful technique among various assays used for diagnosis purposes. The results also pointed out that the prevalence of SLE disease in males is much lower than females. 4 tabs.

  7. Identification of MAMDC1 as a candidate susceptibility gene for systemic lupus erythematosus (SLE.

    Directory of Open Access Journals (Sweden)

    Anna Hellquist

    2009-12-01

    Full Text Available Systemic lupus erythematosus (SLE is a complex autoimmune disorder with multiple susceptibility genes. We have previously reported suggestive linkage to the chromosomal region 14q21-q23 in Finnish SLE families.Genetic fine mapping of this region in the same family material, together with a large collection of parent affected trios from UK and two independent case-control cohorts from Finland and Sweden, indicated that a novel uncharacterized gene, MAMDC1 (MAM domain containing glycosylphosphatidylinositol anchor 2, also known as MDGA2, MIM 611128, represents a putative susceptibility gene for SLE. In a combined analysis of the whole dataset, significant evidence of association was detected for the MAMDC1 intronic single nucleotide polymorphisms (SNP rs961616 (P -value = 0.001, Odds Ratio (OR = 1.292, 95% CI 1.103-1.513 and rs2297926 (P -value = 0.003, OR = 1.349, 95% CI 1.109-1.640. By Northern blot, real-time PCR (qRT-PCR and immunohistochemical (IHC analyses, we show that MAMDC1 is expressed in several tissues and cell types, and that the corresponding mRNA is up-regulated by the pro-inflammatory cytokines tumour necrosis factor alpha (TNF-alpha and interferon gamma (IFN-gamma in THP-1 monocytes. Based on its homology to known proteins with similar structure, MAMDC1 appears to be a novel member of the adhesion molecules of the immunoglobulin superfamily (IgCAM, which is involved in cell adhesion, migration, and recruitment to inflammatory sites. Remarkably, some IgCAMs have been shown to interact with ITGAM, the product of another SLE susceptibility gene recently discovered in two independent genome wide association (GWA scans.Further studies focused on MAMDC1 and other molecules involved in these pathways might thus provide new insight into the pathogenesis of SLE.

  8. Significance of abnormal myocardial perfusion scintigraphy in young adult patients with SLE

    International Nuclear Information System (INIS)

    Zakavi, S.R.; Kakhki, V.R.D.; Sadeghi, R.; Jokar, M.H.; Khazaei, G.

    2009-01-01

    Detection of subclinical coronary artery disease (CAD) is a potential challenge in patients with systemic lupus erythematosus (SLE) and it is suggested that myocardial perfusion single photon emission computerized tomography (SPECT) is more sensitive than exercise test in this setting. However, the significance of perfusion abnormalities in SLE patients is not well known. In this study, we evaluated the prognostic significance of myocardial perfusion defects in patients with SLE. Patients with proven diagnosis of SLE admitted to the hospital due to noncardiac problems with no history of CAD were studied. All patients underwent 99m Tc-methoxyisobutylisonitrile (MIBI) myocardial perfusion scan using dipyridamole as pharmacological stress. All patients were followed up by reviewing patients file in lupus clinic and any minor or major cardiac events were recorded. Eighteen female and two male patients with mean age of 28.2±12.05 years were included. Six patients had mild reversible perfusion defects with mean summed difference score of 2.5±1.0. Pattern of reverse redistribution (reverse fill-in) was noted in three patients. Eleven patients had normal myocardial perfusion. Hypokinesia was noted in three patients on gated images. One patient with abnormal perfusion died 21 days after imaging due to on-cardiac cause. Nineteen patients were followed for a mean time of 39.2±16.0 months. No major or minor cardiac events were noted during follow-up. Three patients (one with abnormal perfusion) had at least one readmission during follow-up period. Our study showed that myocardial perfusion abnormalities are fairly frequent in SLE patients but the defects are generally mild and do not advocate an adverse prognosis. (author)

  9. Screening for cognitive impairment in SLE using the Self-Administered Gerocognitive Exam.

    Science.gov (United States)

    Meara, A; Davidson, N; Steigelman, H; Zhao, S; Brock, G; Jarjour, W N; Rovin, B H; Madhoun, H; Parikh, S; Hebert, L; Ayoub, I; Ardoin, S P

    2018-01-01

    Objective Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that can affect the central nervous system in multiple ways, including causing cognitive dysfunction. Cognitive dysfunction is a common complaint of SLE patients yet diagnosis is challenging, time consuming, and costly. This study evaluated the Self-Administered Gerocognitive Exam (SAGE) as a screening test for cognitive impairment in a cohort of SLE patients. Methods A total of 118 SLE patients completed the SAGE. Providers completed the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and the Systemic Lupus International Collaborative Clinics Damage Index (SLICC-DI). SAGE scores were grouped into normal (>16) and abnormal (≤16) categories. Univariate and multivariate analyses were performed. Results Of the 118 participants, 21(18%) scored ≤16 on the SAGE instrument. In univariate analysis, race, ethnicity, household income, and SLICC-DI scores were associated with the SAGE ( p SAGE score was independently associated with higher SLICC-DI score (odds ratio (OR) = 1.44, 95% confidence intervals 1.04-1.99, p = 0.03)), Hispanic ethnicity (OR = 43.4, 95% CI 3.1-601, p = 0.005), and lower household income (OR = 11.9 for ≤$15,000 vs >$50,000, 95% CI 2.45-57, p = 0.002). Conclusions In SLE patients, this study demonstrates an independent relationship between neurocognitive impairment (as measured by the SAGE) and higher lupus-related damage, as measured by the SLICC-DI, and lower household income. Abnormal SAGE scores were also associated with Hispanic ethnicity. A language barrier could explain this because the SAGE instrument was conducted in English only. The SAGE was feasible to measure in the clinic setting.

  10. Decreased SAP expression in T cells from patients with SLE contributes to early signaling abnormalities and reduced IL-2 production

    Science.gov (United States)

    Karampetsou, Maria P.; Comte, Denis; Kis-Toth, Katalin; Terhorst, Cox; Kyttaris, Vasileios C.; Tsokos, George C.

    2016-01-01

    T cells from patients with systemic lupus erythematosus (SLE) display a number of functions including increased early signaling events following engagement of the T cell receptor (TCR). Signaling lymphocytic activation molecule family (SLAMF) cell surface receptors and the X-chromosome-defined signaling lymphocytic activation molecule-associated protein (SAP) adaptor are important in the development of several immunocyte lineages and modulating immune response. Here we present evidence that SAP protein levels are decreased in T cells and in their main subsets isolated from 32 women and 3 men with SLE independently of disease activity. In SLE T cells the SAP protein is also subject to increased degradation by a caspase-3. Forced expression of SAP in SLE T cells simultaneously heightened IL-2 production, calcium (Ca2+) responses and tyrosine phosphorylation of a number of proteins. Exposure of normal T cells to SLE serum IgG, known to contain anti-CD3/TCR antibodies, resulted in SAP downregulation. We conclude that SLE T cells display reduced levels of the adaptor protein SAP probably as a result of continuous T cell activation and degradation by caspase-3. Restoration of SAP levels in SLE T cells corrects the overexcitable lupus T cell phenotype. PMID:27183584

  11. Genetic Association of CD247 (CD3ζ) with SLE in a Large-Scale Multiethnic Study

    OpenAIRE

    Martins, Madalena; Williams, Adrienne H.; Comeau, Mary; Marion, Miranda; Ziegler, Julie T.; Freedman, Barry I.; Merrill, Joan T.; Glenn, Stuart B.; Kelly, Jennifer A.; Sivils, Kathy M.; James, Judith A.; Guthridge, Joel M.; Alarcón-Riquelme, Marta E.; Bae, Sang-Cheol; Kim, Jae-Hoon

    2015-01-01

    A classic T-cell phenotype in systemic lupus erythematosus (SLE) is the downregulation and replacement of the CD3ζ chain that alters T-cell receptor signaling. However, genetic associations with SLE in the human CD247 locus that encodes CD3ζ are not well established and require replication in independent cohorts. Our aim was therefore to examine, localize and validate CD247-SLE association in a large multiethnic population. We typed 44 contiguous CD247 single-nucleotide polymorphisms (SNPs) i...

  12. Preferential binding to Elk-1 by SLE-associated IL10 risk allele upregulates IL10 expression.

    Directory of Open Access Journals (Sweden)

    Daisuke Sakurai

    Full Text Available Immunoregulatory cytokine interleukin-10 (IL-10 is elevated in sera from patients with systemic lupus erythematosus (SLE correlating with disease activity. The established association of IL10 with SLE and other autoimmune diseases led us to fine map causal variant(s and to explore underlying mechanisms. We assessed 19 tag SNPs, covering the IL10 gene cluster including IL19, IL20 and IL24, for association with SLE in 15,533 case and control subjects from four ancestries. The previously reported IL10 variant, rs3024505 located at 1 kb downstream of IL10, exhibited the strongest association signal and was confirmed for association with SLE in European American (EA (P = 2.7×10⁻⁸, OR = 1.30, but not in non-EA ancestries. SNP imputation conducted in EA dataset identified three additional SLE-associated SNPs tagged by rs3024505 (rs3122605, rs3024493 and rs3024495 located at 9.2 kb upstream, intron 3 and 4 of IL10, respectively, and SLE-risk alleles of these SNPs were dose-dependently associated with elevated levels of IL10 mRNA in PBMCs and circulating IL-10 protein in SLE patients and controls. Using nuclear extracts of peripheral blood cells from SLE patients for electrophoretic mobility shift assays, we identified specific binding of transcription factor Elk-1 to oligodeoxynucleotides containing the risk (G allele of rs3122605, suggesting rs3122605 as the most likely causal variant regulating IL10 expression. Elk-1 is known to be activated by phosphorylation and nuclear localization to induce transcription. Of interest, phosphorylated Elk-1 (p-Elk-1 detected only in nuclear extracts of SLE PBMCs appeared to increase with disease activity. Co-expression levels of p-Elk-1 and IL-10 were elevated in SLE T, B cells and monocytes, associated with increased disease activity in SLE B cells, and were best downregulated by ERK inhibitor. Taken together, our data suggest that preferential binding of activated Elk-1 to the IL10 rs3122605-G allele

  13. Microstructures and Microhardness Properties of CMSX-4® Additively Fabricated Through Scanning Laser Epitaxy (SLE)

    Science.gov (United States)

    Basak, Amrita; Holenarasipura Raghu, Shashank; Das, Suman

    2017-12-01

    Epitaxial CMSX-4® deposition is achieved on CMSX-4® substrates through the scanning laser epitaxy (SLE) process. A thorough analysis is performed using various advanced material characterization techniques, namely high-resolution optical microscopy, scanning electron microscopy, energy-dispersive x-ray spectroscopy, x-ray diffraction, and Vickers microhardness measurements, to characterize and compare the quality of the SLE-fabricated CMSX-4® deposits to the CMSX-4® substrates. The results show that the CMSX-4® deposits have smaller primary dendritic arm spacing, finer γ/ γ' size, weaker elemental segregation, and higher microhardness compared to the investment cast CMSX-4® substrates. The results presented here demonstrate that CMSX-4® is an attractive material for laser-based AM processing and, therefore, can be used in the fabrication of gas turbine hot-section components through AM processing.

  14. Demyelinating syndrome in SLE: review of different disease subtypes and report of a case series

    Directory of Open Access Journals (Sweden)

    E. Chessa

    2017-12-01

    Full Text Available Demyelinating syndrome (DS is a rare manifestation of systemic lupus erythematosus (SLE (1% with high clinical heterogeneity and potentially severe prognosis. It can represent a diagnostic and therapeutic challenge for clinicians. A recent study described 5 different patterns of demyelinating disease presentation, characterised by specific clinical, laboratory and brain and spine magnetic resonance imaging abnormalities: 1 neuromyelitis optica; 2 neuromyelitis optica spectrum disorders; 3 DS prevalently involving the brain; 4 DS prevalently involving the brainstem; 5 clinically isolated syndrome. In this review we briefly discuss typical characteristics of each DS presentation in SLE and we describe 5 illustrative clinical cases, one for each subset of DS, considering both diagnostic and therapeutic options.

  15. Localization of radiolabeled anti-DNA monoclonal antibodies in murine systemic lupus erythematosus (SLE)

    International Nuclear Information System (INIS)

    Wahl, R.; Hahn, B.; Ebling, F.

    1984-01-01

    The diagnosis of SLE can be extremely difficult. This multi-system disease is characterized by the deposition of DNA-anti-DNA antibody (Ab) complexes in many tissues, producing glomerulonephritis and systemic vasculitis. This study evaluates an IGG monoclonal (Mo) Ab directe3d against DNA (MrSSl) for potential radioimmunodiagnosis of SLE. Six 15 wk. old F-1 female hybrids of NZB+NZW mice (an animal SLE model that develops vasculitis and nephritis) were injected with 50 μCl of I-131 MrSSl and 15 μCl of I-125 isotype-matched control mouse myeloma (LPC-1) (non-reactive with DNA). Imaging and tissue distribution were studied. Two animals were also imaged using I-131 LPC Ab. Images at 2 and 9 days showed no clear differences in scan patterns using MrSSl or LPC-1 Ab. Tissue distribution studies at six days, however, showed a significantly higher accumulation of MrSSl in the kidneys vs. control Ab (2.7% vs. 1.8% of injected dose) (p < .04). Similarly, higher levels of MrSS were also seen in the spleen, liver and lungs (p < .03). Blood levels tended to be higher with the specific antibody as well. These differences were not apparent at 3 days post injection. The increased concentration of MrSSl present at 9 days in several organs may be secondary to MrSSl binding to DNA containing immune complexes present in diseased tissues. Blocked clearance by immune complexes or DNA, or differences in electrical charges of the antibodies could be contributing to the higher MrSSl levels seen. Images did not suggest deiodination as responsible. Further studies are necessary to determine if the amount of MrSSl retained by diseased animals is indicative of SLE disease activity

  16. Damage in the Multiethnic Malaysian Systemic Lupus Erythematosus (SLE) Cohort: Comparison with Other Cohorts Worldwide

    Science.gov (United States)

    Shaharir, Syahrul Sazliyana; Hussein, Heselynn; Rajalingham, Sakthiswary; Mohamed Said, Mohd Shahrir; Abdul Gafor, Abdul Halim; Mohd, Rozita; Mustafar, Ruslinda

    2016-01-01

    Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease and despite the improvement in the survival in the past few decades, the morbidity due to disease damage remains significant. The objectives of this study were to investigate the disease damagepattern and determine the associated factors of damage in the multi-ethnic Malaysian SLE patients. We consecutively 424SLE patients who attended a consistent follow-up at the National University of Malaysia Medical Centre and Putrajaya Hospital were recruited. Disease damage was assessed using the SLICC/ACR (Systemic Lupus International Collaborating Clinics/American College of Rheumatology) Damage Index (SDI) scores. Information on their demographics and disease characteristics were obtained from the clinical record. Univariate analysis was performed and the best model of independent predictors of disease damage was determined by multivariate logistic regression analysis. A total of 182 patients (42.9%) had disease damage (SDI ≥1). A significantly higher number of Indian patients had disease/organ damage and they predominantly developed steroid-induced diabetes mellitus (SDM). Patients with corticosteroid-induced osteoporosis (CIOP) were more likely to be Malayswhile majority of patients who developed malignancy were Chinese (p<0.05). In the univariate and multivariate analyses, disease damage was significantly associated with age, Indian ethnicity, lower mean cumulative C3 level, neuropsychiatry lupus (NPSLE), and antiphospholipid syndrome (APLS). Patients who had ever and early treatment with hydroxychloroquine(HCQ)were less likely to develop disease damage while more patients who had received oral prednisolone ≥1mg/kg daily over 2 weeks had disease damage (p<0.05). In conclusion, there were inter-ethnic differences in the damage pattern and risks among SLE patients. PMID:27846298

  17. Depression and ways of coping in SLE induced arthritis patient: a case study

    International Nuclear Information System (INIS)

    Farah, D.; Nezam, N.; Naz, H.

    2012-01-01

    Systemic lupus erythematosus is a systemic autoimmune disease (autoimmune connective tissue disease) that most often harms the heart, joints, skin, lungs, blood vessels, liver, kidneys and nervous system. One of the outcomes of SLE is arthritis which is a group of conditions involving damage to the joints of the body. One of the most common types is rheumatoid arthritis which is an autoimmune immune disease. This SLE induced arthritis has many impacts on every aspect of life including biological, psychological, social and - financial domains. In most of the cases arthritis is associated With depression and anxiety. It is envisaged that people with arthritis suffer more from depression as compared to general population. The present study was designed to evaluate depression using lung Self Rating Scale and coping using two scales: Ways of Coping and Coping Self Efficacy in a 27 years old female participant with SLE induced Arthritis. The results of the two paradigms and detailed case history revealed that the level of depression lies in the normal range that coincides with the use of effective coping strategies. Thus the participant's positive outlook enabled to improve the quality of life. (author)

  18. Early and delayed Tc-99m ECD brain SPECT in SLE patients with CNS involvement

    International Nuclear Information System (INIS)

    Kikukawa, Kaoru; Toyama, Hiroshi; Katayama, Masao

    2000-01-01

    We compared early and delayed Tc-99m ECD SPECT scans in 32 SLE patients (Group 1, definite neuropsychiatric disorders; Group 2, minor neurologic symptoms or normal) with those of normal controls by visual inspection and semi-quantitative evaluation. With visual interpretation, 13 out of 14 patients in Group 1 (93%) and 7 out of 18 patients in Group 2 (39%) had diffuse uneven decrease in early scans. Seven patients in Group 2 (39%) who had normal early scans demonstrated focal decrease in the medial frontal lobe in delayed scans. With cerebral region to cerebellar ratios, in early scans, the medial frontal lobe in Group 1 and Group 2 was significantly lower than in normal controls, and lateral frontal lobe and occipital lobes in Group 1 were significantly lower than in normal controls. Nevertheless, in delayed scans, every cortical region except for the parietal lode in Groups 1 and 2 was significantly lower than in normal controls. The retention rates in all regions in SLE patients were significantly lower than in normal controls. No case showed SPECT improvement on follow-up studies in either group in spite of clinical improvement. Delayed Tc-99m ECD brain SPECT of high sensitivity might be useful in detecting CNS involvement. Although the SPECT findings did not correlate with the neuropsychiatric symptoms, early and delayed Tc-99m ECD SPECT seems to provide useful objective diagnostic information in SLE patients. (author)

  19. 3rd international software language engineering conference (SLE) : pre-proceedings, October 12-13, 2010, Eindhoven, the Netherlands

    OpenAIRE

    Brand, van den, M.G.J.; Malloy, B.; Staab, S.

    2010-01-01

    We are pleased to present the proceedings of the Third International Conference on Software Language Engineering (SLE 2010). The conference will be held in Eindhoven, the Netherlands during October 12-13, 2010 and will be co-located with The Ninth International Conference on Generative Programming and Component Engineering (GPCE'10), and The Workshop on Feature-Oriented Software Development (FOSD). An important goal of SLE is to integrate the different sub-communities of the software-language...

  20. SLE disease patterns in a Danish population-based lupus cohort: an 8-year prospective study

    DEFF Research Database (Denmark)

    Laustrup, H; Voss, A; Green, A

    2009-01-01

    In 1995 all systemic lupus erythematosus (SLE) patients in the county of Funen were retrieved from four separate and independent sources as part of an 8-year prospective study to determine the pattern of disease activity and damage accumulation in a community based lupus cohort of predominantly...... Scandinavian ancestry. Incident cases were subsequently identified by surveillance of these sources. Established and new cases underwent annual, structured interviews, clinical examination and blood sampling. The Systemic Lupus Erythematosus Diseases Activity Index SLEDAI and Systemic Lupus International...

  1. Investigations of a rabbit (Oryctolagus cuniculus model of systemic lupus erythematosus (SLE, BAFF and its receptors.

    Directory of Open Access Journals (Sweden)

    Jiahui Yang

    2009-12-01

    Full Text Available B-cell activation factor belonging to the tumor necrosis factor family (BAFF is a major contributor to survival of B lymphocytes during development and maturation. A relationship between circulating BAFF levels and disease activity has been reported in patients with the autoimmune disease Systemic Lupus Erythematosus (SLE. Clinical trials targeting BAFF or its receptors are currently in progress. In order to further characterize a rabbit (Oryctolagus cuniculus model of SLE, we investigated the expression of BAFF and its receptors in non-inbred, pedigreed rabbits derived from breeding and selection based on autoantibody responses. We immunized rabbits related to previous groups that developed autoantibodies and inflammatory responses after immunizations with peptides synthesized on multiple antigen-branched polylysine backbones. Blood and sera collected before immunization and after boosts were used for health monitoring, analyses of serum autoantibody responses by ELISA and immunofluorescence. Peripheral blood mononuclear cells (PBMC were studied by flow cytometry and were the source of mRNA for quantitative PCR analyses. We hypothesized that BAFF mRNA expression and serum BAFF levels measured indirectly through BAFF receptor binding might increase in autoantibody-producing rabbits. Immunized rabbits developed elevated levels of leucocyte populations, anti-nuclear, anti-dsDNA and other autoantibodies. BR3 mRNA levels in total PBMC decreased and BAFF levels remained low and unchanged in most immunized rabbits. By flow cytometry, percentages of BAFF positive cells decreased. Percentages of transmembrane activator and CAML interactor (TACI decreased in most rabbits from all the immunized groups. The rabbit is an important model for human autoimmune and infectious diseases, and a high quality draft rabbit genome assembly was recently completed. Human disease models developed in non-inbred pedigreed animals are better able to reflect the complexities

  2. Association of anti C1q and ds-DNA levels with the pathogenesis of Lupus Nephritis among SLE patients

    Directory of Open Access Journals (Sweden)

    Zara Sohail

    2018-02-01

    Full Text Available Background: Lupus nephritis (LN is the most common and serious complication associated with SLE and it results in significant morbidity and mortality. It is known by several studies that patients of LN have higher levels of anti-dsDNA and anti-C1q compared with SLE patients without renal involvement. The current study was designed to determine and compare the level of anti-dsDNA and anti-C1q in patients of SLE with and without lupus nephritis in the Pakistani population. This current study was also aimed at providing proof that anti-C1q levels are more prominent in LN/non-LN SLE as compared to anti-dsDNA. This project may help in the determination of results in Pakistan and contribute to the further confirmation of the sensitivity of anti-C1q. Method: The patient samples were collected from Sheikh Zayed hospital, Lahore. These patients were clinically diagnosed by the Rheumatologists as SLE and LN positive on the basis of ACR and SLEDAI scoring criteria. This study was performed and samples were analyzed in the Department of Medical and Laboratory Sciences, Imperial College of Business Study, Lahore on the patient’s serum by ELISA technique. Result: About 38% (12 patients with LN were positive for anti-dsDNA and 31% (9 SLE patients without LN were positive whereas about 38.7% (12 were anti-dsDNA negative in LN cases and 58.6% (17 in SLE without LN. In case of anti-C1q 100% (31 of these LN patients were positive and 93.1% (27 patients SLE without LN showed positive anti C1q results. Only 6.9% (2 patients showed negative results for anti-C1q in LN negative patients Conclusion: The higher levels of anti-C1q suggest that it may be a better diagnostic marker for LN than that of anti-dsDNA and that it can be helpful in the prognosis of SLE patients.

  3. Analysis of systemic lupus erythematosus (SLE) involving the central nervous system by magnetic resonance imaging (MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kimihiro; Hara, Masako; Nakajima, Shinji and others

    1989-04-01

    Involvement of the central nervous system (CNS) commonly occurs in systemic lupus erythematosus (SLE). But definitive diagnosis remains difficult even with computed tomography (CT). In this study, we used the recently developed technique, magnetic resonance imaging (MRI) for CNS lupus and compared it with CT scans. CT was performed with a General Electric 8800 CT/T scanner. MRI was performed using a Mitsubishi Electric MMI-150 S. Ten patients with CNS lupus were divided into 3 groups. Group I included 4 cases with neurological manifestations alone. All lesions seen on CT were also detected by MRI, with greater clarity and extent. Furthermore, MRI depicted several microinfarcts in white matter without symptoms. Group II included 5 cases with psychiatric features alone. MRI detected a thalamic microinfarct in only one case while CT showed no abnormality in all cases. Group III included 1 case with both neurological and psychiatric symptoms. MRI demonstrated a small infarct of midbrain corresponding with neurological symptoms, more clearly than CT. Therefore MRI demonstrates the degree of brain involvement in SLE more accurately than CT. (author).

  4. Analysis of systemic lupus erythematosus (SLE) involving the central nervous system by magnetic resonance imaging (MRI)

    International Nuclear Information System (INIS)

    Suzuki, Kimihiro; Hara, Masako; Nakajima, Shinji

    1989-01-01

    Involvement of the central nervous system (CNS) commonly occurs in systemic lupus erythematosus (SLE). But definitive diagnosis remains difficult even with computed tomography (CT). In this study, we used the recently developed technique, magnetic resonance imaging (MRI) for CNS lupus and compared it with CT scans. CT was performed with a General Electric 8800 CT/T scanner. MRI was performed using a Mitsubishi Electric MMI-150 S. Ten patients with CNS lupus were divided into 3 groups. Group I included 4 cases with neurological manifestations alone. All lesions seen on CT were also detected by MRI, with greater clarity and extent. Furthermore, MRI depicted several microinfarcts in white matter without symptoms. Group II included 5 cases with psychiatric features alone. MRI detected a thalamic microinfarct in only one case while CT showed no abnormality in all cases. Group III included 1 case with both neurological and psychiatric symptoms. MRI demonstrated a small infarct of midbrain corresponding with neurological symptoms, more clearly than CT. Therefore MRI demonstrates the degree of brain involvement in SLE more accurately than CT. (author)

  5. Genotoxic effect and antigen binding characteristics of SLE auto-antibodies to peroxynitrite-modified human DNA.

    Science.gov (United States)

    Khan, Md Asad; Alam, Khursheed; Mehdi, Syed Hassan; Rizvi, M Moshahid A

    2017-12-01

    Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disease characterized by auto-antibodies against native deoxyribonucleic acid after modification and is one of the reasons for the development of SLE. Here, we have evaluated the structural perturbations in human placental DNA by peroxynitrite using spectroscopy, thermal denaturation and high-performance liquid chromatography (HPLC). Peroxynitrite is a powerful potent bi-functional oxidative/nitrative agent that is produced both endogenously and exogenously. In experimental animals, the peroxynitrite-modified DNA was found to be highly immunogenic. The induced antibodies showed cross-reactions with different types of DNA and nitrogen bases that were modified with peroxynitrite by inhibition ELISA. The antibody activity was inhibited by approximately 89% with its immunogen as the inhibitor. The antigen-antibodies interaction between induced antibodies with peroxynitrite-modified DNA showed retarded mobility as compared to the native form. Furthermore, significantly increased binding was also observed in SLE autoantibodies with peroxynitrite-modified DNA than native form. Moreover, DNA isolated from lymphocyte of SLE patients revealed significant recognition of anti-peroxynitrite-modified DNA immunoglobulin G (IgG). Our data indicates that DNA modified with peroxynitrite presents unique antigenic determinants that may induce autoantibody response in SLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Outcome of lupus nephritis in childhood onset SLE in North and Central India: single-centre experience over 25 years.

    Science.gov (United States)

    Srivastava, P; Abujam, B; Misra, R; Lawrence, A; Agarwal, V; Aggarwal, A

    2016-04-01

    Childhood SLE (cSLE) has a higher prevalence of lupus nephritis (LN), and there are ethnic variations in response to treatment as well as outcome of LN. There are limited data on long-term outcome of LN in cSLE from the Indian subcontinent. Retrospective analysis of case records of patients with cSLE (satisfying revised American College of Rheumatology (ACR) 1997 criteria for diagnosis) and age of onset Collaborating Clinics (SLICC)/ACR damage score was 0.79 ± 1.13. Actuarial ESRD-free survival at five, 10 and 15 years was 91.1%, 79% and 76.2%, and five-, 10- and 15-year renal survival was 93.8%, 87.1% and 84%, respectively. Although multiple factors individually predicted poor outcome (death/ESRD), only raised serum creatinine at onset (R square = 0.65, p ≤ 0.0001) and damage accrual (R square = 0.62, p ≤ 0.0001) remained significant on multivariate analysis. Eleven (8.2%) children died during the follow-up period, and infections were the leading cause of mortality. Long-term outcome of LN in cSLE in our cohort was better than previous reports from India. However, a high rate of major infection still remains the leading cause of mortality. © The Author(s) 2015.

  7. High-density genotyping of immune-related loci identifies new SLE risk variants in individuals with Asian ancestry.

    Science.gov (United States)

    Sun, Celi; Molineros, Julio E; Looger, Loren L; Zhou, Xu-Jie; Kim, Kwangwoo; Okada, Yukinori; Ma, Jianyang; Qi, Yuan-Yuan; Kim-Howard, Xana; Motghare, Prasenjeet; Bhattarai, Krishna; Adler, Adam; Bang, So-Young; Lee, Hye-Soon; Kim, Tae-Hwan; Kang, Young Mo; Suh, Chang-Hee; Chung, Won Tae; Park, Yong-Beom; Choe, Jung-Yoon; Shim, Seung Cheol; Kochi, Yuta; Suzuki, Akari; Kubo, Michiaki; Sumida, Takayuki; Yamamoto, Kazuhiko; Lee, Shin-Seok; Kim, Young Jin; Han, Bok-Ghee; Dozmorov, Mikhail; Kaufman, Kenneth M; Wren, Jonathan D; Harley, John B; Shen, Nan; Chua, Kek Heng; Zhang, Hong; Bae, Sang-Cheol; Nath, Swapan K

    2016-03-01

    Systemic lupus erythematosus (SLE) has a strong but incompletely understood genetic architecture. We conducted an association study with replication in 4,478 SLE cases and 12,656 controls from six East Asian cohorts to identify new SLE susceptibility loci and better localize known loci. We identified ten new loci and confirmed 20 known loci with genome-wide significance. Among the new loci, the most significant locus was GTF2IRD1-GTF2I at 7q11.23 (rs73366469, Pmeta = 3.75 × 10(-117), odds ratio (OR) = 2.38), followed by DEF6, IL12B, TCF7, TERT, CD226, PCNXL3, RASGRP1, SYNGR1 and SIGLEC6. We identified the most likely functional variants at each locus by analyzing epigenetic marks and gene expression data. Ten candidate variants are known to alter gene expression in cis or in trans. Enrichment analysis highlights the importance of these loci in B cell and T cell biology. The new loci, together with previously known loci, increase the explained heritability of SLE to 24%. The new loci share functional and ontological characteristics with previously reported loci and are possible drug targets for SLE therapeutics.

  8. Angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism is not a risk factor for hypertension in SLE nephritis.

    Science.gov (United States)

    Negi, Vir S; Devaraju, Panneer; Gulati, Reena

    2015-09-01

    SLE is a systemic autoimmune disease with high prevalence of hypertension. Around 40-75 % of SLE patients develop nephritis, a major cause of hypertension and mortality. Angiotensin-converting enzyme (ACE) maintains the blood pressure and blood volume homeostasis. An insertion/deletion (I/D) polymorphism in intron 16 of ACE gene was reported to influence the development of hypertension, nephritis, and cardiovascular diseases in different ethnic populations. Despite compelling evidence for the high prevalence of hypertension in individuals with SLE, underlying factors for its development are not well studied. With this background, we analyzed the influence of ACE insertion/deletion polymorphism on susceptibility to SLE, development of nephritis and hypertension, other clinical features and autoantibody phenotype in South Indian SLE patients. Three hundred patients with SLE and 460 age and sex similar ethnicity matched individuals were included as patients and healthy controls, respectively. The ACE gene insertion/deletion polymorphism was analyzed by PCR. Insertion (I) and deletion (D) alleles were observed to be equally distributed among patients (57 and 43 %) and controls (59 and 41 %), respectively. The mutant (D) allele did not confer significant risk for SLE (II vs. ID: p = 0.4, OR 1.15, 95 % CI 0.8-1.6; II vs. DD: p = 0.34, OR 1.22, 95 % CI 0.8-1.85). There was no association of the ACE genotype or the allele with development of lupus nephritis (II vs. ID: p = 0.19, OR 1.41, 95 % CI 0.84-2.36; II vs. DD: p = 0.41, OR 0.74, 95 % CI 0.38-1.41) or hypertension (II vs. ID: p = 0.85, OR 0.9, 95 % CI 0.43-1.8; II vs. DD: p = 0.66, OR 1.217, 95 % CI 0.5-2.8). The presence of mutant allele (D) was not found to influence any clinical features or autoantibody phenotype. The insertion/deletion polymorphism of the ACE gene is not a genetic risk factor for SLE and does not influence development of hypertension or lupus nephritis in South Indian

  9. Complement receptor expression and activation of the complement cascade on B lymphocytes from patients with systemic lupus erythematosus (SLE)

    DEFF Research Database (Denmark)

    Marquart, H V; Svendsen, A; Rasmussen, J M

    1995-01-01

    It has previously been reported that the expression of the complement receptors, CR1 on erythrocytes and blood leucocytes and CR2 on B cells, is reduced in patients with SLE, and that the reduced expression of CR1 on erythrocytes is related to disease activity. We have earlier demonstrated...... that normal B cells are capable of activating the alternative pathway (AP) of complement in a CR2-dependent fashion. In this study we have investigated whether disturbances in this activity may be related to the altered phenotype of SLE B cells. Flow cytometry was used to measure expression of complement...

  10. U-Net/SLE: A Java-Based User-Customizable Virtual Network Interface

    Directory of Open Access Journals (Sweden)

    Matt Welsh

    1999-01-01

    Full Text Available We describe U‐Net/SLE (Safe Language Extensions, a user‐level network interface architecture which enables per‐application customization of communication semantics through downloading of user extension applets, implemented as Java classfiles, to the network interface. This architecture permits applications to safely specify code to be executed within the NI on message transmission and reception. By leveraging the existing U‐Net model, applications may implement protocol code at the user level, within the NI, or using some combination of the two. Our current implementation, using the Myricom Myrinet interface and a small Java Virtual Machine subset, allows host communication overhead to be reduced and improves the overlap of communication and computation during protocol processing.

  11. Course of Neuropsychiatric Symptoms during Flares of Systemic Lupus Erythematosus (SLE

    Directory of Open Access Journals (Sweden)

    Gareth Garrett

    2017-01-01

    Full Text Available We present the case of a seventeen-year-old girl who presents with an interesting course of neuropsychiatric symptoms during several flares of SLE. The patient was diagnosed at the age of thirteen and has had four flares in total. The latter two flares included cutaneous and neuropsychiatric symptoms. The most recent flare occurred when she was aged seventeen. She had cutaneous symptoms which coincided with an episode of hypomania. Her mental state further deteriorated following steroid treatment. She exhibited affective and psychotic symptoms. Treatment with cyclophosphamide and olanzapine was associated with an improvement in both cutaneous and neuropsychiatric symptoms. Previously aged sixteen the patient had presented with cutaneous symptoms and a moderate depressive episode which was also exacerbated by steroid treatment. The patient’s mood improved when the dose of oral steroids was reduced to a daily dose of 15–20 mg prednisolone.

  12. Mice, humans and haplotypes--the hunt for disease genes in SLE.

    Science.gov (United States)

    Rigby, R J; Fernando, M M A; Vyse, T J

    2006-09-01

    Defining the polymorphisms that contribute to the development of complex genetic disease traits is a challenging, although increasingly tractable problem. Historically, the technical difficulties in conducting association studies across the entire human genome are such that murine models have been used to generate candidate genes for analysis in human complex diseases, such as SLE. In this article we discuss the advantages and disadvantages of this approach and specifically address some assumptions made in the transition from studying one species to another, using lupus as an example. These issues include differences in genetic structure and genetic organisation which are a reflection on the population history. Clearly there are major differences in the histories of the human population and inbred laboratory strains of mice. Both human and murine genomes do exhibit structure at the genetic level. That is to say, they comprise haplotypes which are genomic regions that carry runs of polymorphisms that are not independently inherited. Haplotypes therefore reduce the number of combinations of the polymorphisms in the DNA in that region and facilitate the identification of disease susceptibility genes in both mice and humans. There are now novel means of generating candidate genes in SLE using mutagenesis (with ENU) in mice and identifying mice that generate antinuclear autoimmunity. In addition, murine models still provide a valuable means of exploring the functional consequences of genetic variation. However, advances in technology are such that human geneticists can now screen large fractions of the human genome for disease associations using microchip technologies that provide information on upwards of 100,000 different polymorphisms. These approaches are aimed at identifying haplotypes that carry disease susceptibility mutations and rely less on the generation of candidate genes.

  13. Chinese SLE Treatment and Research group (CSTAR) registry VII: prevalence and clinical significance of serositis in Chinese patients with systemic lupus erythematosus.

    Science.gov (United States)

    Zhao, J; Bai, W; Zhu, P; Zhang, X; Liu, S; Wu, L; Ma, L; Bi, L; Zuo, X; Sun, L; Huang, C; Tian, X; Li, M; Zhao, Y; Zeng, X

    2016-05-01

    To investigate both the prevalence and clinical characteristics of serositis in Chinese patients with systemic lupus erythematosus (SLE) in a large cohort in the Chinese SLE Treatment and Research group (CSTAR) database. A prospective cross-sectional study of patients with SLE was conducted based on the data from the CSTAR registry. Serositis was defined according to the 1999 revised American College of Rheumatology (ACR) criteria for SLE - that is, pleuritis/pleural effusion and/or pericarditis/pericardial effusion detected by echocardiography, chest X-ray or chest computerized tomography (CT) scan. Peritonitis/peritoneal effusion were confirmed by abdominal ultrasonography. We analysed the prevalence and clinical associations of serositis with demographic data, organ involvements, laboratory findings and SLE disease activity. Of 2104 patients with SLE, 345 were diagnosed with serositis. The prevalence of lupus nephritis (LN), interstitial lung disease and pulmonary arterial hypertension, as well as the presence of leukocytopenia, thrombocytopenia, hypocomplementemia and anti-dsDNA antibodies was significantly higher in patients with serositis (P Lupus-related peritonitis had similar clinical manifestations and laboratory profiles as serositis caused by SLE. There is a significant association of nephropathy, interstitial lung disease, pulmonary arterial hypertension, hypocomplementemia, leukocytopenia, thrombocytopenia and elevated anti-dsDNA antibodies with serositis. The results suggest that higher SLE disease activity contributes to serositis development, and should be treated aggressively. © The Author(s) 2016.

  14. 3rd international software language engineering conference (SLE) : pre-proceedings, October 12-13, 2010, Eindhoven, the Netherlands

    NARCIS (Netherlands)

    Brand, van den M.G.J.; Malloy, B.; Staab, S.

    2010-01-01

    We are pleased to present the proceedings of the Third International Conference on Software Language Engineering (SLE 2010). The conference will be held in Eindhoven, the Netherlands during October 12-13, 2010 and will be co-located with The Ninth International Conference on Generative Programming

  15. High mobility group box1 (HMGB1) in relation to cutaneous inflammation in systemic lupus erythematosus (SLE)

    NARCIS (Netherlands)

    Abdulahad, D.A.; Westra, J.; Reefman, E.; Zuidersma, E.; Bijzet, J.; Limburg, P.C.; Kallenberg, C.G.M.; Bijl, M.

    2013-01-01

    Photosensitivity is characteristic of systemic lupus erythematosus (SLE). Upon ultraviolet B (UVB) exposure, patients develop inflammatory skin lesions in the vicinity of sunburn cells (SBCs). High mobility group box 1 (HMGB1) is released from apoptotic and activated cells and exerts inflammatory

  16. Behavioral Deficits Are Accompanied by Immunological and Neurochemical Changes in a Mouse Model for Neuropsychiatric Lupus (NP-SLE)

    DEFF Research Database (Denmark)

    Li, Yan; Eskelund, Amanda; Zhou, H

    2015-01-01

    pathophysiological mechanisms responsible for NP-SLE are increased peripheral pro-inflammatory cytokines, subsequent induction of indoleamine-2,3-dioxygenase (IDO) and activation of the kynurenine pathway. In the MRL/MpJ-Faslpr (MRL/lpr) murine model of lupus, depression-like behavior and cognitive dysfunction...

  17. Fas expression on peripheral blood lymphocytes in systemic lupus erythematosus (SLE) : relation to lymphocyte activation and disease activity

    NARCIS (Netherlands)

    Bijl, M; Horst, G; Limburg, PC; Kallenberg, CGM

    2001-01-01

    Levels of apoptotic lymphocytes have been found to be increased in SLE and persistence of apoptotic cells has been associated with autoantibody production, Increased lymphocyte Fas (CD95) expression due to lymphocyte activation may account for increased Susceptibility to Fas-mediated apoptosis in

  18. Sex influences eQTL effects of SLE and Sjögren's syndrome-associated genetic polymorphisms.

    Science.gov (United States)

    Lindén, Magdalena; Ramírez Sepúlveda, Jorge I; James, Tojo; Thorlacius, Gudny Ella; Brauner, Susanna; Gómez-Cabrero, David; Olsson, Tomas; Kockum, Ingrid; Wahren-Herlenius, Marie

    2017-10-25

    Systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS) are autoimmune disorders characterized by autoantibodies, dysregulated B cells, and notably high female-to-male incidence ratios. Genome-wide association studies have identified several susceptibility SNPs for both diseases. Many SNPs in the genome are expression quantitative trait loci (eQTLs), with context-dependent effects. Assuming that sex is a biological context, we investigated whether SLE/pSS SNPs act as eQTLs in B cells and used a disease-targeted approach to understand if they display sex-specific effects. We used genome-wide genotype and gene expression data from primary B cells from 125 males and 162 females. The MatrixEQTL R package was used to identify eQTLs within a genomic window of 2 Mb centered on each of 22 established SLE and/or pSS susceptibility SNPs. To find sex-specific eQTLs, we used a linear model with a SNP * sex interaction term. We found ten SNPs affecting the expression of 16 different genes (FDR rs7574865-INPP1, rs7574865-MYO1B, rs4938573-CD3D, rs11755393-SNRPC, and rs4963128-PHRF1 were novel observations for the immune compartment and B cells. By analyzing the SNP * sex interaction terms, we identified six genes with differentially regulated expression in females compared to males, depending on the genotype of SLE/pSS-associated SNPs: SLC39A8 (BANK1 locus), CD74 (TNIP1 locus), PXK, CTSB (BLK/FAM167A locus), ARCN1 (CXCR5 locus), and DHX9 (NCF2 locus). We identified several unknown sex-specific eQTL effects of SLE/pSS-associated genetic polymorphisms and provide novel insight into how gene-sex interactions may contribute to the sex bias in systemic autoimmune diseases.

  19. Chronic exposure to trichloroethene causes early onset of SLE-like disease in female MRL +/+ mice

    International Nuclear Information System (INIS)

    Cai Ping; Koenig, Rolf; Boor, Paul J.; Kondraganti, Shakuntala; Kaphalia, Bhupendra S.; Khan, M. Firoze; Ansari, G.A.S.

    2008-01-01

    Trichloroethene (TCE) exacerbates the development of autoimmune responses in autoimmune-prone MRL +/+ mice. Although TCE-mediated autoimmune responses are associated with an increase in serum immunoglobulins and autoantibodies, the underlying mechanism of autoimmunity is not known. To determine the progression of TCE-mediated immunotoxicity, female MRL +/+ mice were chronically exposed to TCE through the drinking water (0.5 mg/ml of TCE) for various periods of time. Serum concentrations of antinuclear antibodies increased after 36 and 48 weeks of TCE exposure. Histopathological analyses showed lymphocyte infiltration in the livers of MRL +/+ mice exposed to TCE for 36 or 48 weeks. Lymphocyte infiltration was also apparent in the pancreas, lungs, and kidneys of mice exposed to TCE for 48 weeks. Immunoglobulin deposits in kidney glomeruli were found after 48 weeks of exposure to TCE. Our results suggest that chronic exposure to TCE promotes inflammation in the liver, pancreas, lungs, and kidneys, which may lead to SLE-like disease in MRL +/+ mice

  20. Effect of Proinflammatory Cytokines (IL-6, TNF-α, and IL-1β on Clinical Manifestations in Indian SLE Patients

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    Vinod Umare

    2014-01-01

    Full Text Available Systemic lupus erythematosus (SLE is an inflammatory rheumatic disease characterized by production of autoantibodies and organ damage. Elevated levels of cytokines have been reported in SLE patients. In this study we have investigated the effect of proinflammatory cytokines (IL-6, TNF-α, and IL-1β on clinical manifestations in 145 Indian SLE patients. One hundred and forty-five healthy controls of the same ethnicity served as a control group. Clinical disease activity was scored according to SLEDAI score. Accordingly, 110 patients had active disease and 35 patients had inactive disease. Mean levels of IL-6, TNF-α, and IL-1β were found to be significantly higher in SLE patients than healthy controls (P<0.001. Mean level of IL-6 for patients with active disease (70.45±68.32 pg/mL was significantly higher (P=0.0430 than those of inactive disease patients (43.85±63.36 pg/mL. Mean level of TNF-α was 44.76±68.32 pg/mL for patients with active disease while it was 25.97±22.03 pg/mL for those with inactive disease and this difference was statistically significant (P=0.0161. Similar results were obtained for IL-1β (P=0.0002. Correlation between IL-6, TNF-α, and IL-1β serum levels and SLEDAI score was observed (r=0.20, r=0.27, and r=0.38, resp.. This study supports the role of these proinflammatory cytokines as inflammatory mediators in active stage of disease.

  1. Characterization of Novel PI3Kδ Inhibitors as Potential Therapeutics for SLE and Lupus Nephritis in Pre-Clinical Studies.

    Science.gov (United States)

    Haselmayer, Philipp; Camps, Montserrat; Muzerelle, Mathilde; El Bawab, Samer; Waltzinger, Caroline; Bruns, Lisa; Abla, Nada; Polokoff, Mark A; Jond-Necand, Carole; Gaudet, Marilène; Benoit, Audrey; Bertschy Meier, Dominique; Martin, Catherine; Gretener, Denise; Lombardi, Maria Stella; Grenningloh, Roland; Ladel, Christoph; Petersen, Jørgen Søberg; Gaillard, Pascale; Ji, Hong

    2014-01-01

    SLE is a complex autoimmune inflammatory disease characterized by pathogenic autoantibody production as a consequence of uncontrolled T-B cell activity and immune-complex deposition in various organs, including kidney, leading to tissue damage and function loss. There is a high unmet need for better treatment options other than corticosteroids and immunosuppressants. Phosphoinositol-3 kinase δ (PI3Kδ) is a promising target in this respect as it is essential in mediating B- and T-cell function in mouse and human. We report the identification of selective PI3Kδ inhibitors that blocked B-, T-, and plasmacytoid dendritic cell activities in human peripheral blood and in primary cell co-cultures (BioMAP(®)) without detecting signs of undesired toxicity. In an IFNα-accelerated mouse SLE model, our PI3Kδ inhibitors blocked nephritis development, whether administered at the onset of autoantibody appearance or the onset of proteinuria. Disease amelioration correlated with normalized immune cell numbers in the spleen, reduced immune-complex deposition as well as reduced inflammation, fibrosis, and tissue damage in the kidney. Improvements were similar to those achieved with a frequently prescribed drug for lupus nephritis, the potent immunosuppressant mycophenolate mofetil. Finally, we established a pharmacodynamics/pharmacokinetic/efficacy model that revealed that a sustained PI3Kδ inhibition of 50% is sufficient to achieve full efficacy in our disease model. These data demonstrate the therapeutic potential of PI3Kδ inhibitors in SLE and lupus nephritis.

  2. The national incidence and clinical picture of SLE in children in Australia - a report from the Australian Paediatric Surveillance Unit.

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    Mackie, F E; Kainer, G; Adib, N; Boros, C; Elliott, E J; Fahy, R; Munro, J; Murray, K; Rosenberg, A; Wainstein, B; Ziegler, J B; Singh-Grewal, D

    2015-01-01

    The objectives of this paper are to prospectively determine the incidence of paediatric systemic lupus erythematosus (pSLE) in Australia as well as describe the demographics, clinical presentation and one-year outcome. Newly diagnosed cases of pSLE were ascertained prospectively from October 2009 to October 2011 through the Australian Paediatric Surveillance Unit (a national monthly surveillance scheme for notification of childhood rare diseases) as well as national subspecialty groups. Questionnaires were sent to notifying physicians at presentation and at one year. The annual incidence rate was 0.32 per 10(5) children aged less than 16 years. The incidence was significantly higher in children of Asian or Australian Aboriginal and Torres Strait Islander parents. Approximately one-third of children underwent a renal biopsy at presentation and 7% required dialysis initially although only one child had end-stage kidney disease (ESKD) at one-year follow-up. The incidence of pSLE in Australia is comparable to that worldwide with a significantly higher incidence seen in children of Asian and Australian Aboriginal and Torres Strait Islander backgrounds. Renal involvement is common but progression to ESKD, at least in the short term, is rare. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  3. Hydroxychloroquine Blood Levels in SLE: Clarifying dosing controversies and improving adherence

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    Durcan, Laura; Clarke, William A; Magder, Laurence S.; Petri, Michelle

    2015-01-01

    OBJECTIVES Hydroxychloroquine is used for its effect on systemic lupus erythematosus (SLE) disease activity and long-term benefits. This can be limited by adherence. One way to assess adherence is to measure blood levels. Conflicting data exist regarding blood levels and disease activity. There is dosing controversy; rheumatologists recommend weight-based, while ophthalmologists advocate height-based ‘ideal body weight’ dosing. METHODS Patients were prescribed hydroxychloroquine not to exceed 6.5mg/kg (max400mg/day). In hemodialysis, the dose was 200mg after each session, in renal insufficiency it was 200mg/day. Levels were measured at each visit with a therapeutic range of 500-2000 ng/ml. Patients were divided according to baseline blood level. To assess the impact of measurement and counseling on adherence, we compared the proportion of patients with a level of 500ng/ml or higher based on how many prior assessments the patient had. RESULTS The proportion of patients with hydroxychloroquine levels in the therapeutic range differed significantly by age, gender and vitamin D level. There was a trend toward lower levels with renal failure. Blood levels were similar regardless of height and ideal body weight. Comparing those with undetectable, sub-therapeutic and therapeutic levels, disease activity decreased (SLEDAI 2.92, 2.36 and 2.20)(P=0.04, for trend). At first, 56% were therapeutic and by the third measurement this increased to 80% (p =hydroxychloroquine levels. Renal failure dosing led to sub-optimum levels. We show that weight-based dosing (max 400mg daily) is appropriate and that height does not appear to influence levels. Measurement, counseling and repeated testing can increase adherences rates. PMID:26428205

  4. Associated factors and impact of myocarditis in patients with SLE from LUMINA, a multiethnic US cohort (LV). [corrected].

    Science.gov (United States)

    Apte, M; McGwin, G; Vilá, L M; Kaslow, R A; Alarcón, G S; Reveille, J D

    2008-03-01

    To examine the factors associated with myocarditis and its impact on disease outcomes in SLE patients. SLE patients aged > or = 16 yrs, disease duration NAture vs nurture), a multiethnic US cohort, were studied. Myocarditis was defined as per the category 3 of the pericarditis/myocarditis item of the SLAM-Revised (SLAM-R). Patients with concurrent pericardial involvement were excluded. Patients with myocarditis were compared with those without myocarditis or its sequelae in the preceding year. The association between myocarditis and baseline variables (T(0)) was first examined. The impact of myocarditis on disease activity over time (SLAM-R), damage accrual [SLICC Damage Index (SDI)] at last visit (T(L)) and mortality was evaluated. Fifty-three of the 496 patients studied had myocarditis. African American ethnicity [Odds ratio (OR) = 12.6; 95% CI 1.6, 97.8] and SLAM-R at diagnosis (OR = 1.1, 95% CI 1.0, 1.1) were significantly and independently associated with myocarditis. Myocarditis did not predict disease activity over time, but approached significance as a predictor of SDI at T(L) in multivariable analyses P = 0.051. Kaplan-Meier curves indicated that myocarditis was associated with shorter survival (log-rank = 4.87, P = 0.02), particularly in patients with > or = 5 yrs disease; however, myocarditis was not retained in the Cox proportional hazards regression model. Ethnicity and disease activity at diagnosis were associated with the occurrence of myocarditis in SLE. Myocarditis did not significantly impact on disease activity over time, but impacts some on damage accrual and survival, reflecting overall the more severe disease those patients experience.

  5. Comparative transcriptional profiling of 3 murine models of SLE nephritis reveals both unique and shared regulatory networks.

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    Ramalingam Bethunaickan

    Full Text Available To define shared and unique features of SLE nephritis in mouse models of proliferative and glomerulosclerotic renal disease.Perfused kidneys from NZB/W F1, NZW/BXSB and NZM2410 mice were harvested before and after nephritis onset. Affymetrix based gene expression profiles of kidney RNA were analyzed using Genomatix Pathway Systems and Ingenuity Pathway Analysis software. Gene expression patterns were confirmed using real-time PCR.955, 1168 and 755 genes were regulated in the kidneys of nephritic NZB/W F1, NZM2410 and NZW/BXSB mice respectively. 263 genes were regulated concordantly in all three strains reflecting immune cell infiltration, endothelial cell activation, complement activation, cytokine signaling, tissue remodeling and hypoxia. STAT3 was the top associated transcription factor, having a binding site in the gene promoter of 60/263 regulated genes. The two strains with proliferative nephritis shared a macrophage/DC infiltration and activation signature. NZB/W and NZM2410 mice shared a mitochondrial dysfunction signature. Dominant T cell and plasma cell signatures in NZB/W mice reflected lymphoid aggregates; this was the only strain with regulatory T cell infiltrates. NZW/BXSB mice manifested tubular regeneration and NZM2410 mice had the most metabolic stress and manifested loss of nephrin, indicating podocyte loss.These findings identify shared inflammatory mechanisms of SLE nephritis that can be therapeutically targeted. Nevertheless, the heterogeneity of effector mechanisms suggests that individualized therapy might need to be based on biopsy findings. Some common mechanisms are shared with non-immune-mediated renal diseases, suggesting that strategies to prevent tissue hypoxia and remodeling may be useful in SLE nephritis.

  6. Expression and methylation data from SLE patient and healthy control blood samples subdivided with respect to ARID3a levels

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    Julie M. Ward

    2016-12-01

    Full Text Available Previously published studies revealed that variation in expression of the DNA-binding protein ARID3a in B lymphocytes from patients with systemic lupus erythematosus (SLE correlated with levels of disease activity (“Disease activity in systemic lupus erythematosus correlates with expression of the transcription factor AT-rich-interactive domain 3A” (J.M. Ward, K. Rose, C. Montgomery, I. Adrianto, J.A. James, J.T. Merrill et al., 2014 [1]. The data presented here compare DNA methylation patterns from SLE peripheral blood mononuclear cells obtained from samples with high numbers of ARID3a expressing B cells (ARID3aH versus SLE samples with normal numbers of ARID3a+ B cells (ARID3aN. The methylation data is available at the gene expression omnibus (GEO repository, “Gene Expression Omnibus: NCBI gene expression and hybridization array data repository” (R. Edgar, M. Domrachev, A.E. Lash, 2002 [2]. Isolated B cells from SLE ARID3aH and ARID3aN B samples were also evaluated via qRT-PCR for Type I interferon (IFN signature and pathway gene expression levels by qRT-PCR. Similarly, healthy control B cells and B cells stimulated to express ARID3a with the TLR agonist, CpG, were also compared via qRT-PCR. Primers designed to detect 6 IFNa subtype mRNAs were tested in 4 IFNa, Epstein-Barr Virus-transformed B cell lines (“Reduced interferon-alpha production by Epstein-Barr virus transformed B-lymphoblastoid cell lines and lectin-stimulated lymphocytes in congenital dyserythropoietic anemia type I” (S.H. Wickramasinghe, R. Hasan, J. Smythe, 1997 [3]. The data in this article support the publication, “Human effector B lymphocytes express ARID3a and secrete interferon alpha” (J.M. Ward, M.L. Ratliff, M.G. Dozmorov, G. Wiley, J.M. Guthridge, P.M. Gaffney, J.A. James, C.F. Webb, 2016 [4].

  7. Effect of hydroxychloroquine treatment on pro-inflammatory cytokines and disease activity in SLE patients: data from LUMINA (LXXV), a multiethnic US cohort

    Science.gov (United States)

    Willis, R; Seif, AM; McGwin, G; Martinez-Martinez, LA; González, EB; Dang, N; Papalardo, E; Liu, J; Vilá, LM; Reveille, JD; Alarcón, GS; Pierangeli, SS

    2013-01-01

    Objective We sought to determine the effect of hydroxychloroquine therapy on the levels proinflammatory/prothrombotic markers and disease activity scores in patients with systemic lupus erythematosus (SLE) in a multiethnic, multi-center cohort (LUMINA). Methods Plasma/serum samples from SLE patients (n=35) were evaluated at baseline and after hydroxychloroquine treatment. Disease activity was assessed using SLAM-R scores. Interferon (IFN)-α2, interleukin (IL)-1β, IL-6, IL-8, inducible protein (IP)-10, monocyte chemotactic protein-1, tumor necrosis factor (TNF)-α and soluble CD40 ligand (sCD40L) levels were determined by a multiplex immunoassay. Anticardiolipin antibodies were evaluated using ELISA assays. Thirty-two frequency-matched plasma/serum samples from healthy donors were used as controls. Results Levels of IL-6, IP-10, sCD40L, IFN-α and TNF-α were significantly elevated in SLE patients versus controls. There was a positive but moderate correlation between SLAM-R scores at baseline and levels of IFN-α (p=0.0546). Hydroxychloroquine therapy resulted in a significant decrease in SLAM-R scores (p=0.0157), and the decrease in SLAM-R after hydroxychloroquine therapy strongly correlated with decreases in IFN-α (p=0.0087). Conclusions Hydroxychloroquine therapy resulted in significant clinical improvement in SLE patients, which strongly correlated with reductions in IFN-α levels. This indicates an important role for the inhibition of endogenous TLR activation in the action of hydroxychloroquine in SLE and provides additional evidence for the importance of type I interferons in the pathogenesis of SLE. This study underscores the use of hydroxychloroquine in the treatment of SLE. PMID:22343096

  8. Detection of Catalase as a major protein target of the lipid peroxidation product 4-HNE and the lack of its genetic association as a risk factor in SLE

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    Matsumoto Hiroyuki

    2008-07-01

    Full Text Available Abstract Background Systemic lupus erythematosus (SLE is a multifactorial disorder characterized by the presence of autoantibodies. We and others have implicated free radical mediated peroxidative damage in the pathogenesis of SLE. Since harmful free radical products are formed during this oxidative process, including 4-hydroxy 2-nonenol (4-HNE and malondialdehyde (MDA, we hypothesized that specific HNE-protein adducts would be present in SLE red blood cell (RBC membranes. Catalase is located on chromosome 11p13 where linkage analysis has revealed a marker in the same region of the genome among families with thrombocytopenia, a clinical manifestation associated with severe lupus in SLE affected pedigrees. Moreover, SLE afflicts African-Americans three times more frequently than their European-American counterparts. Hence we investigated the effects of a genetic polymorphism of catalase on risk and severity of SLE in 48 pedigrees with African American ancestry. Methods Tryptic digestion followed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS analysis was used to identify the protein modified by HNE, following Coomassie staining to visualize the bands on the acrylamide gels. Genotyping analysis for the C → T, -262 bp polymorphism in the promoter region of catalase was performed by PCR-RFLP and direct PCR-sequencing. We used a "pedigree disequilibrium test" for the family based association analysis, implemented in the PDT program to analyze the genotyping results. Results We found two proteins to be HNE-modified, migrating around 80 and 50 kD respectively. Tryptic digestion followed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS analysis of the Coomassie stained 80 kD band revealed that the target of HNE modification was catalase, a protein shown to associate with RBC membrane proteins. All the test statistics carried out on the genotyping analysis for the

  9. Chinese SLE Treatment and Research Group Registry: III. Association of Autoantibodies with Clinical Manifestations in Chinese Patients with Systemic Lupus Erythematosus

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    Jing Li

    2014-01-01

    Full Text Available We investigated the characteristics of Chinese SLE patients by analyzing the association between specific autoantibodies and clinical manifestations of 2104 SLE patients from registry data of CSTAR cohort. Significant (P<0.05 associations were found between anti-Sm antibody, anti-rRNP antibody, and malar rash; between anti-RNP antibody, anti-SSA antibody, and pulmonary arterial hypertension (PAH; between anti-SSB antibody and hematologic involvement; and between anti-dsDNA antibody and nephropathy. APL antibody was associated with hematologic involvement, interstitial lung disease, and a lower prevalence of oral ulcerations (P<0.05. Associations were also found between anti-dsDNA antibody and a lower prevalence of photosensitivity, and between anti-SSA antibody and a lower prevalence of nephropathy (P<0.05. Most of these findings were consistent with other studies in the literature but this study is the first report on the association between anti-SSA and a lower prevalence of nephropathy. The correlations of specific autoantibodies and clinical manifestations could provide clues for physicians to predict organ damages in SLE patients. We suggest that a thorough screening of autoantibodies should be carried out when the diagnosis of SLE is established, and repeated echocardiography annually in SLE patients with anti-RNP or anti-SSA antibody should be performed.

  10. The relationship between increased levels of Anti-dsDNA with clinical manifestation in patients with SLE in Haji Adam Malik General Hospital Medan

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    Marpaung, B.; Patrick, J.

    2018-03-01

    Systemic Lupus Erythematosus (SLE) is an autoimmune rheumatic disease characterized by widespread inflammation and affects any organism the body. Many autoimmune diseases result in autoantibody production, but Anti-dsDNA antibodies are highly specific to SLE. Previous study found that Anti-dsDNA antibodies are associated with severe clinical manifestations of lupus. The aim of this study was to examine the relationship between anti-dsDNA level with clinical features and laboratory findings in SLE patients. This cross-sectional study was conducted in Hospital Haji Adam Malik Medan in May-October 2016.We examine anti-dsDNA, clinical features and kidney laboratory profile in all patient. Data were statistically analyzed.81 SLE patients with median level of anti-dsDNA 294 (6.1-1317). There was no significant relationship between increased level of Anti-dsDNA with clinical manifestations (p>0.05). There were significant relationships between increased level of Anti-dsDNA with renal impairment (p=0.049), urea level (p=0.016), urine protein (p=0.042) and hematology disorder (p=0.005). Arthritis is the most frequent clinical manifestation (96.3%) followed by malar rash (77.8%). Elevated anti-dsDNA level was not related with clinical manifestations but there was significant relationship with hematology disorder, urea, creatinine, and proteinuria in SLE patents.

  11. Evaluation and treatment of acute psychosis in children with Systemic Lupus Erythematosus (SLE): consultation-liaison service experiences at a tertiary-care pediatric institution.

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    Muscal, Eyal; Nadeem, Tania; Li, Xiofan; Mian, Ayesha; Harris, Toi Blakley

    2010-01-01

    Neurological and psychiatric manifestations of systemic lupus erythematosus (SLE) are prevalent in children with SLE. There are few data on the evaluation and management of psychotic features in children with this systemic autoimmune disorder. The authors describe contemporary Child and Adolescent Psychiatry Consultation and Liaison service management of acute psychosis in children with lupus. The authors reviewed the records (2003-2008) of all pediatric SLE inpatients who were administered a traditional or atypical antipsychotic agent. They describe clinical features, initial and discharge mental status examinations, and inpatient psychotropic medication usage. Ten pediatric SLE patients (age 10-19 years) required psychiatric management for psychosis during the review period. Paranoid delusions (70%), visual hallucinations (60%), and auditory hallucinations (60%) were the most common psychotic symptoms documented. All children were initially treated with an antipsychotic medication. Seven children were maintained on an atypical antipsychotic during their hospitalization. Two children had extrapyramidal signs, but no other adverse events were documented. All children were improved at discharge, and 40% had complete resolution of psychosis; 8 of the 10 patients were discharged on a psychotropic medication. Psychotic manifestations associated with severe disease presentations were successfully treated by child psychiatrists. Atypical antipsychotics were well-tolerated and used as an adjunct to immunosuppressive regimens in these patients. Prospective studies are necessary to improve the care of children and adolescents with SLE and severe psychiatric manifestations.

  12. Change in autoantibody and cytokine responses during the evolution of neuromyelitis optica in patients with systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Kovacs, Katalin T; Kalluri, Sudhakar Reddy; Boza-Serrano, Antonio

    2016-01-01

    BACKGROUND: Neuromyelitis optica (NMO)-systemic lupus erythematosus (SLE) association is a rare condition characterized by multiple autoantibodies. OBJECTIVE: To examine if, during the evolution of NMO, anti-AQP4 responses are part of polyclonal B cell activation, and if T cell responses contribute...

  13. [Depressive disorder in Mexican pediatric patients with systemic lupus erythematosus (SLE)].

    Science.gov (United States)

    Carbajal-Alonso, Hilda Lilian; García-Moreno, Norberta Prisilia; Rodríguez-Arreola, Brenda; Barrera de León, Juan Carlos

    2016-01-01

    To identify the prevalence of depression in Mexican pediatric patients with systemic lupus erythematosus. Analytical transversal study including patients aged 7-16 years with a diagnosis of systemic lupus erythematosus seen at the Pediatric Rheumatology Consultation Service. The disease was classified by means of the MEX-SLEDAI questionnaire. Descriptive statistics with central tendency and dispersion and comparative measurements with chi-squared and Mann-Whitney U tests. Logistic regression and association with odds ratios. SPSS v.21.0 statistical software package. We evaluated 45 patients who presented depression, n=9 (20%), including eight females (89%) and one male (11%), median age 13 years (range, 7-16) in children with depression vs. 13 years (range, 9-14) p=0.941, depression more frequent in schoolchildren. Habitual residence, disease evolution time, and duration of the immunosuppressor did not show a significant difference between both groups. Divorced parents p=0.037. Neuropsychiatric manifestations of lupus presented in 2.2% of all patients and in 100% of patients with depression. Disease activity index (MEX-SLEDAI) did not demonstrate a relationship with the presence of depression. Prevalences in pediatric populations are less that that reported in adults, association with disease activity, evolution time, and immunosuppressor use and duration not found.

  14. Poly(hydroxyethyl methacrylate) based affinity membranes for in vitro removal of anti-dsDNA antibodies from SLE plasma.

    Science.gov (United States)

    Uzun, Lokman; Yavuz, Handan; Osman, Bilgen; Celik, Hamdi; Denizli, Adil

    2010-07-01

    The preparation of polymeric membrane using affinity technology for application in blood filtration devices is described here. DNA attached poly(hydroxyethyl methacrylate) (PHEMA) based microporous affinity membrane was prepared for selective removal of anti-dsDNA antibodies from systemic lupus erythematosus (SLE) patient plasma in in vitro. In order to further increase blood-compatibility of affinity membrane, aminoacid based comonomer N-methacryloyl-L-alanine (MAAL) was included in the polymerization recipe. PHEMAAL membrane was produced by a photopolymerization technique and then characterized by swelling tests and scanning electron microscope (SEM) studies. Blood-compatibility tests were also performed. The water swelling ratio of PHEMAAL membrane increased significantly (133.2%) compared with PHEMA (58%). PHEMAAL membrane has large pores around in the range of 5-10 microm. All the clotting times increased when compared with PHEMA membrane. Loss of platelets and leukocytes was very low. DNA loading was 7.8 mg/g. There was a very low anti-dsDNA-antibody adsorption onto the plain PHEMAAL membrane, about 78 IU/g. The PHEMAAL-DNA membrane adsorbed anti-dsDNA-antibody in the range of 10-68 x 10(3)IU/g from SLE plasma. Anti-dsDNA-antibody concentration decreased significantly from 875 to 144 IU/ml with the time. Anti-dsDNA-antibodies could be repeatedly adsorbed and eluted without noticeable loss in the anti-dsDNA-antibody adsorption amount. (c) 2010 Elsevier B.V. All rights reserved.

  15. The combination of two Sle2 lupus-susceptibility loci and Cdkn2c deficiency leads to T cell-mediated pathology in B6.Faslpr mice

    Science.gov (United States)

    Xu, Zhiwei; Croker, Byron P.; Morel, Laurence

    2013-01-01

    The NZM2410 Sle2c1 lupus susceptibility locus is responsible for the expansion of the B1a cell compartment and for the induction of T-cell induced renal and skin pathology on a CD95 deficient (Faslpr)-background. We have previously shown that deficiency in cyclin-dependent kinase inhibitor p18INK4c (p18) was responsible for the B1a cell expansion but was not sufficient to account for the pathology in B6.lpr mice. This study was designed to map the additional Sle2c1 loci responsible for autoimmune pathology when co-expressed with CD95 deficiency. The production, fine-mapping and phenotypic characterization of five recombinant intervals indicated that three interacting sub-loci were responsive for inducting autoimmune pathogenesis in B6.lpr mice. One of these sub-loci corresponds most likely to p18-deficiency. Another major locus mapping to a 2 Mb region at the telomeric end of Sle2c1 is necessary to both renal and skin pathology. Finally, a third locus centromeric to p18 enhances the severity of lupus nephritis. These results provide new insights into the genetic interactions leading to SLE disease presentation, and represent a major step towards the identification of novel susceptibility genes involved in T-cell mediated organ damage. PMID:23698709

  16. Population differences in SLE susceptibility genes: STAT4 and BLK, but not PXK, are associated with systemic lupus erythematosus in Hong Kong Chinese.

    Science.gov (United States)

    Yang, W; Ng, P; Zhao, M; Hirankarn, N; Lau, C S; Mok, C C; Chan, T M; Wong, R W S; Lee, K W; Mok, M Y; Wong, S N; Avihingsanon, Y; Lee, T L; Ho, M H K; Lee, P P W; Wong, W H S; Lau, Y L

    2009-04-01

    In this study, we compared the association of several newly discovered susceptibility genes for systemic lupus erythematosus (SLE) between populations of European origin and two Asian populations. Using 910 SLE patients and 1440 healthy controls from Chinese living in Hong Kong, and 278 SLE patients and 383 controls in Thailand, we studied association of STAT4, BLK and PXK with the disease. Our data confirmed association of STAT4 (rs7574865, odds ratio (OR) =1.71, P=3.55 x 10(-23)) and BLK (rs13277113, OR=0.77, P=1.34 x 10(-5)) with SLE. It was showed that rs7574865 of STAT4 is also linked to hematologic disorders and potentially some other subphenotypes of the disease. More than one genetic variant in STAT4 were found to be associated with the disease independently in our populations (rs7601754, OR=0.59, P=1.39 x 10(-9), and P=0.00034 when controlling the effect of rs7574865). With the same set of samples, however, our study did not detect any significant disease association for PXK, a risk factor for populations of European origin (rs6445975, joint P=0.36, OR=1.06, 95% confidence interval: 0.93-1.21). Our study indicates that some of the susceptibility genes for this disease may be population specific.

  17. Preeclampsia in pregnancies complicated by systemic lupus erythematosus (SLE) nephritis: prophylactic treatment with multidisciplinary approach are important keys to prevent adverse obstetric outcomes.

    Science.gov (United States)

    Mecacci, Federico; Simeone, Serena; Cirami, Calogero Lino; Cozzolino, Mauro; Serena, Caterina; Rambaldi, Marianna Pina; Gallo, Pamela; Emmi, Lorenzo; Cammelli, Daniele; Mello, Giorgio; Matucci Cerinic, Marco

    2017-11-27

    Systemic lupus erythematosus (SLE) commonly affects women of childbearing age. Hypertension, antiphospholipid syndrome, and lupus nephritis are risk factors for adverse maternal/fetal outcome. The aim of this retrospective cohort study is to compare pregnancy outcomes in patients with and without SLE nephritis, using a multidisciplinary approach and a broad prophylaxis protocol. Data were collected from 86 pregnancies complicated by SLE. Twenty-seven women with nephropathy before pregnancy stated as the study group and 59 formed the control group. Each group received a prophylactic treatment based on their clinical characteristics. Results were expressed as mean ± SD, percentage and χ 2 -test (significant values when p 1.2 mg/dL, which was related to a risk 1.25 times higher than the risk observed in patients with serum creatinine approach in a tertiary care center and a broad prophylactic treatment protocol to patients affected by SLE and complicated by nephritis may definitively foster a successful pregnancy.

  18. Association of the interferon signature metric with serological disease manifestations but not global activity scores in multiple cohorts of patients with SLE

    Science.gov (United States)

    Kennedy, William P; Maciuca, Romeo; Wolslegel, Kristen; Tew, Wei; Abbas, Alexander R; Chaivorapol, Christina; Morimoto, Alyssa; McBride, Jacqueline M; Brunetta, Paul; Richardson, Bruce C; Davis, John C; Behrens, Timothy W; Townsend, Michael J

    2015-01-01

    Objectives The interferon (IFN) signature (IS) in patients with systemic lupus erythematosus (SLE) includes over 100 genes induced by type I IFN pathway activation. We developed a method to quantify the IS using three genes—the IS metric (ISM)—and characterised the clinical characteristics of patients with SLE with different ISM status from multiple clinical trials. Methods Blood microarray expression data from a training cohort of patients with SLE confirmed the presence of the IS and identified surrogate genes. We assayed these genes in a quantitative PCR (qPCR) assay, yielding an ISM from the IS. The association of ISM status with clinical disease characteristics was assessed in patients with extrarenal lupus and lupus nephritis from four clinical trials. Results Three genes, HERC5, EPSTI and CMPK2, correlated well with the IS (p>0.96), and composed the ISM qPCR assay. Using the 95th centile for healthy control data, patients with SLE from different studies were classified into two ISM subsets—ISM-Low and ISM-High—that are longitudinally stable over 36 weeks. Significant associations were identified between ISM-High status and higher titres of anti-dsDNA antibodies, presence of anti extractable nuclear antigen autoantibodies, elevated serum B cell activating factor of the tumour necrosis factor family (BAFF) levels, and hypocomplementaemia. However, measures of overall clinical disease activity were similar for ISM-High and ISM-Low groups. Conclusions The ISM is an IS biomarker that divides patients with SLE into two subpopulations—ISM-High and ISM-Low—with differing serological manifestations. The ISM does not distinguish between high and low disease activity, but may have utility in identifying patients more likely to respond to treatment(s) targeting IFN-α. Clinicaltrials.gov registration number NCT00962832. PMID:25861459

  19. "We Would Still Find Things to Talk About": Assessment of Mentor Perspectives in a Systemic Lupus Erythematosus Intervention to Improve Disease Self-Management, Empowering SLE Patients.

    Science.gov (United States)

    Flournoy-Floyd, Minnjuan; Ortiz, Kasim; Egede, Leonard; Oates, Jim C; Faith, Trevor D; Williams, Edith M

    2018-04-01

    Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disorder with significant disparate impact on African American women. The current study sought to highlight how the Peer Approaches to Lupus Self-management (PALS) intervention worked bi-directionally wherein both women with SLE leading the disease self-management program (mentors), and those participants who served as mentees, were empowered toward greater disease self-efficacy. Data was captured for this study in two formats from the seven mentors participating in the pilot study: 1) mentor logs and 2) mentor interviews with the principle investigator. This information was then analyzed for themes relating to their experience within the study. We found that empowerment was facilitated by mentors taking their mentorship responsibilities seriously and seeking several avenues for collaboratively developing success with their mentees. Mentors reported that although challenges arose, their desire for success resulted in multiple approaches to be flexible and responsive to the needs of their mentees. Additionally, reciprocity was found to be a vital element of the program. Key thematic areas supported our ability to demonstrate the usefulness of a peer mentoring program for SLE disease self-management on evoking empowerment through reciprocal relationships among mentors and mentees within our study population. Furthermore the feedback from PALS participants yielded very rich and contextual information that can be used as a thematic guide for developing and refining evidence-based interventions that seek to incorporate empowerment into disease self-management efforts for women suffering from SLE. Copyright © 2018 National Medical Association. Published by Elsevier Inc. All rights reserved.

  20. The ATP-Dependent Protease ClpP Inhibits Biofilm Formation by Regulating Agr and Cell Wall Hydrolase Sle1 in Staphylococcus aureus

    Science.gov (United States)

    Liu, Qian; Wang, Xing; Qin, Juanxiu; Cheng, Sen; Yeo, Won-Sik; He, Lei; Ma, Xiaowei; Liu, Xiaoyun; Li, Min; Bae, Taeok

    2017-01-01

    Biofilm causes hospital-associated infections on indwelling medical devices. In Staphylococcus aureus, Biofilm formation is controlled by intricately coordinated network of regulating systems, of which the ATP-dependent protease ClpP shows an inhibitory effect. Here, we demonstrate that the inhibitory effect of ClpP on biofilm formation is through Agr and the cell wall hydrolase Sle1. Biofilm formed by clpP mutant consists of proteins and extracellular DNA (eDNA). The increase of the protein was, at least in part, due to the reduced protease activity of the mutant, which was caused by the decreased activity of agr. On the other hand, the increase of eDNA was due to increased cell lysis caused by the higher level of Sle1. Indeed, as compared with wild type, the clpP mutant excreted an increased level of eDNA, and showed higher sensitivity to Triton-induced autolysis. The deletion of sle1 in the clpP mutant decreased the biofilm formation, the level of eDNA, and the Triton-induced autolysis to wild-type levels. Despite the increased biofilm formation capability, however, the clpP mutant showed significantly reduced virulence in a murine model of subcutaneous foreign body infection, indicating that the increased biofilm formation capability cannot compensate for the intrinsic functions of ClpP during infection. PMID:28555174

  1. The ATP-Dependent Protease ClpP Inhibits Biofilm Formation by Regulating Agr and Cell Wall Hydrolase Sle1 in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Qian Liu

    2017-05-01

    Full Text Available Biofilm causes hospital-associated infections on indwelling medical devices. In Staphylococcus aureus, Biofilm formation is controlled by intricately coordinated network of regulating systems, of which the ATP-dependent protease ClpP shows an inhibitory effect. Here, we demonstrate that the inhibitory effect of ClpP on biofilm formation is through Agr and the cell wall hydrolase Sle1. Biofilm formed by clpP mutant consists of proteins and extracellular DNA (eDNA. The increase of the protein was, at least in part, due to the reduced protease activity of the mutant, which was caused by the decreased activity of agr. On the other hand, the increase of eDNA was due to increased cell lysis caused by the higher level of Sle1. Indeed, as compared with wild type, the clpP mutant excreted an increased level of eDNA, and showed higher sensitivity to Triton-induced autolysis. The deletion of sle1 in the clpP mutant decreased the biofilm formation, the level of eDNA, and the Triton-induced autolysis to wild-type levels. Despite the increased biofilm formation capability, however, the clpP mutant showed significantly reduced virulence in a murine model of subcutaneous foreign body infection, indicating that the increased biofilm formation capability cannot compensate for the intrinsic functions of ClpP during infection.

  2. Expansion of PD-1-positive effector CD4 T cells in an experimental model of SLE: contribution to the self-organized criticality theory.

    Science.gov (United States)

    Miyazaki, Yumi; Tsumiyama, Ken; Yamane, Takashi; Ito, Mitsuhiro; Shiozawa, Shunichi

    2013-04-18

    We have developed a systems biology concept to explain the origin of systemic autoimmunity. From our studies of systemic lupus erythematosus (SLE) we have concluded that this disease is the inevitable consequence of over-stimulating the host's immune system by repeated exposure to antigen to levels that surpass a critical threshold, which we term the system's "self-organized criticality". We observed that overstimulation of CD4 T cells in mice led to the development of autoantibody-inducing CD4 T cells (aiCD4 T) capable of generating various autoantibodies and pathological lesions identical to those observed in SLE. We show here that this is accompanied by the significant expansion of a novel population of effector T cells characterized by expression of programmed death-1 (PD-1)-positive, CD27(low), CD127(low), CCR7(low) and CD44(high)CD62L(low) markers, as well as increased production of IL-2 and IL-6. In addition, repeated immunization caused the expansion of CD8 T cells into fully-matured cytotoxic T lymphocytes (CTL) that express Ly6C(high)CD122(high) effector and memory markers. Thus, overstimulation with antigen leads to the expansion of a novel effector CD4 T cell population that expresses an unusual memory marker, PD-1, and that may contribute to the pathogenesis of SLE.

  3. The Sarawak lupus cohort: clinical features and disease patterns of 633 SLE patients in a single tertiary centre from East Malaysia.

    Science.gov (United States)

    Teh, C L; Ling, G R; Aishah, Wan Sharifah

    2015-01-01

    Systemic lupus erythematosus (SLE) has been well studied in West Malaysian populations but lacking in East Malaysian populations. The aim of this study was to examine the clinical features and disease patterns of patients with SLE in a multiethnic East Malaysian population in Sarawak. All SLE patients who were treated in Sarawak General Hospital were reviewed in a retrospective longitudinal study using a standard protocol from 1 January 2006 to 31 December 2013. There were a total of 633 patients in our study with the female to male ratio of 12:1. Our study patients were of multiethnic origins with predominant Chinese ethnic group. They had a mean age of 36.9 ± 13.2 years and a mean duration of illness of 7.2 ± 6.0 years. The main involvements were haematological (74.2 %), malar rash (64.0 %) and renal (58.6 %). Chinese patients were less likely to have discoid lupus, pleuritis and pericarditis, while Malay patients were more likely to have arthritis. Bidayuh patients were more likely to have oral ulcer. Secondary antiphospholipid syndrome was more common in Chinese. The majority of patients were in clinical remission with low SDI. There were 58 deaths (9.2 %) during 2006-2013 with the main causes of death being flare of disease and infection.

  4. Microthrombotic renal involvement in an SLE patient with concomitant catastrophic antiphospholipid syndrome: the beneficial effect of rituximab treatment.

    Science.gov (United States)

    Diószegi, Á; Tarr, T; Nagy-Vincze, M; Nánásy-Vass, M; Veisz, R; Bidiga, L; Dezső, B; Balla, J; Szodoray, P; Szekanecz, Z; Soltész, P

    2018-01-01

    Antiphospholipid syndrome is characterized by multiple arterial and/or venous thrombotic events, recurrent fetal losses in the presence of antiphospholipid antibodies (aPL). Catastrophic antiphospholipid syndrome is a life-threatening, rare subset of antiphospholipid syndrome when the thrombotic events affect at least three organs, and clinical manifestations develop simultaneously or within a week. Diagnostically, small vessel occlusions can be detected by histopathology in the presence of aPL. Our case report describes an 18-year-old man who has been treated for antiphospholipid syndrome associated with systemic lupus erythematosus (SLE) since 2011. The clinical findings were dominated by recurrent deep vein thrombosis, and severe proteinuria caused by lupus nephritis, accompanied by mild serological and laboratory findings. The patient was hospitalized in March 2014 because of severe thrombocytopenia and infective diarrhoea. At this time the renal functions deteriorated rapidly. Simultaneously, left upper extremity paresis was observed; computed tomography showed ischaemic lesions in the territory of the middle cerebral artery. Abdominal discomfort and pain occurred. On computed tomography scan ischaemic lesions were seen in the spleen, the right kidney and the coeliac trunk. Laboratory and serological findings verified the presence of aPL and anti-DNA antibodies, anaemia and thrombocytopenia. Based on the above-mentioned clinical and laboratory findings, the diagnosis of catastrophic antiphospholipid syndrome was established. Anticoagulation, corticosteroids and plasma exchange treatment, as well as haemodiafiltration were initiated. Although the thrombotic cascade decelerated following these interventions, we could not see an improvement in the renal function. Rituximab treatment was started, leading to a significant improvement in renal function. After 5 weeks of treatment the patient was discharged from hospital.

  5. The effect of Ramadan fasting on quiescent systemic lupus erythematosus (SLE) patients' disease activity, health quality of life and lipid profile: a pilot study.

    Science.gov (United States)

    Goharifar, Hamid; Faezi, Seyedeh Tahereh; Paragomi, Pedram; Montazeri, Ali; Banihashemi, Arash Tehrani; Akhlaghkhah, Maryam; Abdollahi, Bahar Sadeghi; Kamazani, Zahra; Akbarian, Mahmood

    2015-08-01

    SLE is a common autoimmune disease with considerable morbidity. Ramadan fasting is a religious custom Muslims regularly practice. We aimed to evaluate the effect of Ramadan fasting on SLE patients' disease activity, health quality of life and lipid profile. We conducted this case control study as a pilot study in 40 quiescent SLE patients, 21 cases who decided to fast and 19 controls who decided not to have Ramadan fasting between August and November 2009 in lupus unit of Rheumatology Research Center in Tehran University of Medical Sciences, Iran. They were assessed for SLE Disease Activity Index, lipid profile and quality of life with Short-Form 36 (SF-36) Health Survey, 1 day before Ramadan, the day after and 3 months after Ramadan fasting. After 24.1 ± 5.4 (mean ± SD) days of fasting, anti-ds DNA increased for 0.34 ± 0.41 mmol/dL in cases versus 0.07 ± 0.31 in controls (P = 0.026). Likewise C3 increased more dramatically in cases (16.8 ± 17.5 vs. 2.3 ± 13.2 mg/dL, P = 0.006). Three months after fasting, anti-ds DNA was still increased 0.28 ± 0.46 mmol/dL in cases while a 0.02 ± 0.43 mmol/dL drop in controls was detected (P = 0.04). On the contrary, C3 returned to baseline. These changes were not accompanied with significant changes in disease activity and health quality of life. Ramadan fasting had no effect on lipid profile except for delayed total cholesterol decrease in cases in comparison with controls (16.4 ± 29.4 decrease vs. 4.6 ± 23.9 mg/dL decrease, P = 0.018). Ramadan fasting probably has no detrimental effect on SLE patients' disease activity and their quality of life in the quiescent phase of disease.

  6. Defects in the Zeta Chain Expression (ζ in a Group of Patients with SLE, Scleroderma and Late-onset Arthritis, Colombia 2014

    Directory of Open Access Journals (Sweden)

    Heber Siachoque-Montañez

    2014-09-01

    Full Text Available Introduction: Systemic Lupus Erythematosus (SLE, Scleroderma and late-onset arthritis are autoimmune inflammatory diseases (EIA characterized by autoantibody production and presence of abnormal T cells which generate defective immune response. The abnormal expression of key signaling molecules in the defective function of T-lymphocytes plays a significant role in the pathogenesis of autoimmune disease. The T-cells exhibit numerous abnormalities TCRζ1 signaling complex, these aberrations result in altered expression of cytokines and some biochemical events involved in the expression of surface molecules. Defects in the complex may be associated TCRζ to steroids used in autoimmune disease patients due to their powerful anti-inflammatory activity and immunosuppressive properties. The synthetic corticosteroids such as examethasone inhibit the transcriptional activity of some factors such as NFKB and AP-1, which regulate the synthesis of certain cytokines and could be involved in the TCRζ synthesis. Material and Methods: A case-control study, with a 1:1 ratio of cases and controls (13:13. Cases were patients with active autoimmune disease (6 patients with SLE, 5 patients with scleroderma and 2 patients with lateonset arthritis, who have not started treatment with corticosteroids. Controls were patients with no autoimmune disease. The diagnosis was made by the criteria established by the American College of Rheumatology for patients with SLE, scleroderma and late-onset arthritis. A 10 mL sample was obtained by venipuncture whole blood. Total RNA was extracted and RT-PCR was performed using a set of primers flanking a region of 138 base pairs involving exons 2, 3 and 4 of the ζ chain. Results: The values of Z chain amplification showed significant differences in patients with autoimmune disease (0.8214 } 0.1787, med = 0.7368 compared with the control group (0.9225 } 0.1272, med = 0.9830 (p = 0.045, Mann-Withney non-parametric one tailed exact

  7. Influence of molecular weight of DNA on the determination of anti-DNA antibodies in systemic lupus erythematosus (SLE) sera by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Geisert, M; Heicke, B; Metzmann, E; Zahn, R K

    1975-04-01

    Using a radioimmunoassay (RIA) based on the Farr technique with radioactively labeled /sup 3/H-DNA for quantitative measurements of anti-DNA antibodies in sera of patients with systemic lupus erythematosus (SLE), the influence of molecular weight of DNA (ranging from 0.1 x 10/sup 6/ to 22.0 x 10/sup 6/ daltons) on binding and precipitation in this system has been investigated. Comparing our results with mathematical models it follows that one antibody molecule is fixed on the average to a statistical DNA segment of 2 x 10/sup 6/ to 4 x 10/sup 6/ daltons. Furthermore binding capacity of the DNA was found to be independent of the molecular weight, as demonstrated in a double label experiment using /sup 14/C and /sup 3/H-labeled DNA of different size. However, the amount of radioactivity precipitated was found to depend on the molecular weight of the labeled DNA following a non-linear function. It was calculated that a minimal ratio of fixed antibody molecules per a certain size of DNA was necessary for precipitation. The mathematical treatment of the observed non-linear precipitation dependence will be discussed using various statistical models. The results indicate that the quantitative measurements of anti-DNA antibodies with the Farr technique e.g., for diagnosis and control of SLE in clinical immunology is highly dependent on the molecular weight of the labeled DNA used in the assay system and reliable results are only obtained with DNA of a sufficiently high molecular weight. (auth)

  8. STAT4 Associates with SLE Through Two Independent Effects that Correlate with Gene Expression and Act Additively with IRF5 to Increase Risk

    Science.gov (United States)

    Abelson, Anna-Karin; Delgado-Vega, Angélica M.; Kozyrev, Sergey V.; Sánchez, Elena; Velázquez-Cruz, Rafael; Eriksson, Niclas; Wojcik, Jerome; Reddy, Prasad Linga; Lima, Guadalupe; D’Alfonso, Sandra; Migliaresi, Sergio; Baca, Vicente; Orozco, Lorena; Witte, Torsten; Ortego-Centeno, Norberto; Abderrahim, Hadi; Pons-Estel, Bernardo A.; Gutiérrez, Carmen; Suárez, Ana; González-Escribano, Maria Francisca; Martin, Javier; Alarcón-Riquelme, Marta E.

    2013-01-01

    Objectives To confirm and define the genetic association of STAT4 and systemic lupus erythematosus, investigate the possibility of correlations with differential splicing and/or expression levels, and genetic interaction with IRF5. Methods 30 tag SNPs were genotyped in an independent set of Spanish cases and controls. SNPs surviving correction for multiple tests were genotyped in 5 new sets of cases and controls for replication. STAT4 cDNA was analyzed by 5’-RACE PCR and sequencing. Expression levels were measured by quantitative PCR. Results In the fine-mapping, four SNPs were significant after correction for multiple testing, with rs3821236 and rs3024866 as the strongest signals, followed by the previously associated rs7574865, and by rs1467199. Association was replicated in all cohorts. After conditional regression analyses, two major independent signals represented by SNPs rs3821236 and rs7574865, remained significant across the sets. These SNPs belong to separate haplotype blocks. High levels of STAT4 expression correlated with SNPs rs3821236, rs3024866 (both in the same haplotype block) and rs7574865 but not with other SNPs. We also detected transcription of alternative tissue-specific exons 1, indicating presence of tissue-specific promoters of potential importance in the expression of STAT4. No interaction with associated SNPs of IRF5 was observed using regression analysis. Conclusions These data confirm STAT4 as a susceptibility gene for SLE and suggest the presence of at least two functional variants affecting levels of STAT4. Our results also indicate that both genes STAT4 and IRF5 act additively to increase risk for SLE. PMID:19019891

  9. Estudo-piloto: células NK nas gestantes com LES NK cells in pregnant patients with SLE: a preliminary study

    Directory of Open Access Journals (Sweden)

    Alessandra Cardoso Pereira

    2009-08-01

    SLE. OBJECTIVE: To measure the amount of circulating NK cells and their viability in pregnant SLE patients. MATERIALS AND METHODS: Blood samples from four groups of ten patients each were evaluated: 1. GLES: Pregnant SLE patients; 2. PLES: Non-pregnant SLE patients; 3. Gcontrols: Pregnant controls; 4. Controls: Healthy non-pregnant women. In all patients the amount and viability of NK cells was measured by flow cytometry, as well as the total apoptosis by annexin V and propidium iodite staining. RESULTS: Due to the great variability, median of each group was used for evaluation: CD56+ count [GLES (0.10, PLES (0.12, Gcontrols (0.15, Controls (0.08]; total apoptosis (addition of initial and late apoptosis to total number of dead cells [GLES (0.06, PLES (0.04, Gcontrols (0.11, Controls (0.11]. The results for live cells count had low variability, so the averages and standard deviations were used for comparisons: [GLES (0.91±0.06, PLES (0.95±0.03, Gcontrols (0.86±0.11, Controls (0.88+0.08]. CONCLUSION: Although not statistically significant, the total apoptosis in the SLE groups was lower than in the control groups, and the live cell count was higher. This suggests that in SLE patients, pregnant or not, the NK cells have a prolonged life cycle (or have a lower/different turnover, and that there may be a higher immune stimulus making the NK cells take longer to activate the apoptosis process.

  10. Schumpeter's Evolution

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    reworking of his basic theory of economic evolution in Development from 1934, and this reworking was continued in Cycles from 1939. Here Schumpeter also tried to handle the statistical and historical evidence on the waveform evolution of the capitalist economy. Capitalism from 1942 modified the model...

  11. Galactic evolution

    International Nuclear Information System (INIS)

    Pagel, B.

    1979-01-01

    Ideas are considered concerning the evolution of galaxies which are closely related to those of stellar evolution and the origin of elements. Using information obtained from stellar spectra, astronomers are now able to consider an underlying process to explain the distribution of various elements in the stars, gas and dust clouds of the galaxies. (U.K.)

  12. Darwinian evolution

    NARCIS (Netherlands)

    Jagers op Akkerhuis, Gerard A.J.M.; Spijkerboer, Hendrik Pieter; Koelewijn, Hans Peter

    2016-01-01

    Darwinian evolution is a central tenet in biology. Conventionally, the defi nition of Darwinian evolution is linked to a population-based process that can be measured by focusing on changes in DNA/allele frequencies. However, in some publications it has been suggested that selection represents a

  13. Stellar evolution

    CERN Document Server

    Meadows, A J

    2013-01-01

    Stellar Evolution, Second Edition covers the significant advances in the understanding of birth, life, and death of stars.This book is divided into nine chapters and begins with a description of the characteristics of stars according to their brightness, distance, size, mass, age, and chemical composition. The next chapters deal with the families, structure, and birth of stars. These topics are followed by discussions of the chemical composition and the evolution of main-sequence stars. A chapter focuses on the unique features of the sun as a star, including its evolution, magnetic fields, act

  14. Association between paraoxonase-1 gene Q192R and L55M polymorphisms in systemic lupus erythematosus (SLE) and anti-phospholipid syndrome (APS) in a population from Cairo of Egypt.

    Science.gov (United States)

    Ibrahim, Alshaymaa Ahmed; El-Lebedy, Dalia; Ashmawy, Ingy; Hady, Maha Abdel

    2017-06-01

    Paraoxonase-1 (PON1) is involved in the oxidative stress process that cause tissue damage observed in systemic lupus erythematosus (SLE) and anti-phospholipid syndrome (APS). The aim of the present study was to investigate the association of PON1 Q192R and L55M polymorphisms with risk of SLE and associated APS among Egyptian sample. The study included 120 SLE patients (45 without APS and 75 with APS) and 120 healthy subjects. PON1 Q192R and L55M polymorphisms were genotyped by real-time PCR. No significant differences in Q192R genotypes or allele frequencies were found between patients and controls (p = 0.5 and 0.1, respectively). The frequency of the 55M allele was significantly higher in SLE patients than in controls (66.6 vs. 43.3%), while the 55L allele was more frequent in controls (56.6%) than in patients (33.3%) (p = 0.03). The LL genotype was more frequent in controls (21.6%) than in patients (10%) while M allele carrier genotypes (LM + MM) were more frequent among patients (90%) than controls (78.3%), p = 0.04. Also, the 55M allele was more frequent in APS patients (73.3%) than in patients without APS (55.6%), p = 0.004. M allele carrier genotypes (LM + MM) was significantly higher among APS patients (95.4%) than in non-APS patients (80%), p = 0.008. Our results indicated that the PON1 L55M polymorphism associated with SLE and associated APS in a population from Cairo of Egypt, while the Q192R polymorphism plays no role in disease susceptibility. A large scale study to assess PON1 polymorphisms, PON1 activity, and markers of oxidative stress interaction is needed to clarify the role of PON-1 polymorphisms in the pathogenesis of SLE and associated APS.

  15. Animal evolution

    DEFF Research Database (Denmark)

    Nielsen, Claus

    This book provides a comprehensive analysis of evolution in the animal kingdom. It reviews the classical, morphological information from structure and embryology, as well as the new data gained from studies using immune stainings of nerves and muscles and blastomere markings, which makes it possi......This book provides a comprehensive analysis of evolution in the animal kingdom. It reviews the classical, morphological information from structure and embryology, as well as the new data gained from studies using immune stainings of nerves and muscles and blastomere markings, which makes...

  16. Representing Evolution

    DEFF Research Database (Denmark)

    Hedin, Gry

    2012-01-01

    . This article discusses Willumsen's etching in the context of evolutionary theory, arguing that Willumsen is a rare example of an artist who not only let the theory of evolution fuel his artistic imagination, but also concerned himself with a core issue of the theory, namely to what extent it could be applied...

  17. Security Evolution.

    Science.gov (United States)

    De Patta, Joe

    2003-01-01

    Examines how to evaluate school security, begin making schools safe, secure schools without turning them into fortresses, and secure schools easily and affordably; the evolution of security systems into information technology systems; using schools' high-speed network lines; how one specific security system was developed; pros and cons of the…

  18. Cepheid evolution

    International Nuclear Information System (INIS)

    Becker, S.A.

    1984-05-01

    A review of the phases of stellar evolution relevant to Cepheid variables of both Types I and II is presented. Type I Cepheids arise as a result of normal post-main sequence evolutionary behavior of many stars in the intermediate to massive range of stellar masses. In contrast, Type II Cepheids generally originate from low-mass stars of low metalicity which are undergoing post core helium-burning evolution. Despite great progress in the past two decades, uncertainties still remain in such areas as how to best model convective overshoot, semiconvection, stellar atmospheres, rotation, and binary evolution as well as uncertainties in important physical parameters such as the nuclear reaction rates, opacity, and mass loss rates. The potential effect of these uncertainties on stellar evolution models is discussed. Finally, comparisons between theoretical predictions and observations of Cepheid variables are presented for a number of cases. The results of these comparisons show both areas of agreement and disagreement with the latter result providing incentive for further research

  19. Venom Evolution

    Indian Academy of Sciences (India)

    IAS Admin

    Therefore, the platypus sequence was studied to quantify the role of gene duplication in the evolution of venom. ... Platypus venom is present only in males and is used for asserting dominance over com- petitors during the ... Certain toxin gene families are known to re- peatedly evolve through gene duplications. The rapidly ...

  20. Percolation, SLE and related topics

    CERN Document Server

    Kreimer, Dirk; Renormalization and universality in mathematical physics

    2007-01-01

    This book covers a wide range of phenomena in the natural sciences dominated by notions of universality and renormalization. The contributions in this volume are equally broad in their approach to these phenomena, offering the mathematical as well as the perspective of the applied sciences. They explore renormalization theory in quantum field theory and statistical physics, and its connections to modern mathematics as well as physics on scales from the microscopic to the macroscopic.

  1. Nudging Evolution?

    OpenAIRE

    Katharine N. Farrell; Andreas Thiel

    2013-01-01

    This Special Feature, "Nudging Evolution? Critical Exploration of the Potential and Limitations of the Concept of Institutional Fit for the Study and Adaptive Management of Social-Ecological Systems," aims to contribute toward the development of social theory and social research methods for the study of social-ecological system dynamics. Our objective is to help strengthen the academic discourse concerning if, and if so, how, to what extent, and in what concrete ways the concept of institut...

  2. Community Evolution

    OpenAIRE

    Saganowski, Stanisław; Bródka, Piotr; Kazienko, Przemysław

    2016-01-01

    The continuous interest in the social network area contributes to the fast development of this field. The new possibilities of obtaining and storing data facilitate deeper analysis of the entire social network, extracted social groups and single individuals as well. One of the most interesting research topic is the network dynamics and dynamics of social groups in particular, it means analysis of group evolution over time. It is the natural step forward after social community extraction. Havi...

  3. Cluster evolution

    International Nuclear Information System (INIS)

    Schaeffer, R.

    1987-01-01

    The galaxy and cluster luminosity functions are constructed from a model of the mass distribution based on hierarchical clustering at an epoch where the matter distribution is non-linear. These luminosity functions are seen to reproduce the present distribution of objects as can be inferred from the observations. They can be used to deduce the redshift dependence of the cluster distribution and to extrapolate the observations towards the past. The predicted evolution of the cluster distribution is quite strong, although somewhat less rapid than predicted by the linear theory

  4. CHEMICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, Melvin

    1965-06-01

    How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in which organisms capable of leaving their skeletons in the rocks to be fossilized were in existence. This period is sometime prior to approximately 600 million years ago. The earth is believed to have taken its present form approximately 4700 million years ago. We have found in rocks whose age is about 1000 million years certain organic molecules which are closely related to the green pigment of plants, chlorophyll. This seems to establish that green plants were already fluorishing prior to that time. We have now found in rocks of still greater age, namely, 2500 million years, the same kinds of molecules mentioned above which can be attributed to the presence of living organisms. If these molecules are as old as the rocks, we have thus shortened the time available for the generation of the complex biosynthetic sequences which give rise to these specific hydrocarbons (polyisoprenoids) to less than 2000 million years.

  5. Imunidade na gestação normal e na paciente com lúpus eritematoso sistêmico (LES Immunity in the normal pregnancy and in the patient with systemic lupus erythematosus (SLE

    Directory of Open Access Journals (Sweden)

    Alessandra Cardoso Pereira

    2005-06-01

    Full Text Available A gravidez é uma condição fisiológica na qual ocorrem várias mudanças imunoendócrinas com a finalidade de facilitar a imunossupressão e a tolerância aos antígenos paternos e fetais. Na gravidez humana normal existe uma relativa supressão de citocinas tipo Th1 na resposta dos linfócitos, levando a uma prevalência na resposta do tipo Th2. No LES, onde prevalece a resposta imune do tipo Th2, a gravidez pode estar relacionada com a ativação da doença. Este artigo é uma revisão dessas alterações relacionadas com a resposta imune durante a gestação normal e na da paciente com LES.Pregnancy is a physiologic condition where several immuno-endocrine changes take place with the aim of facilitating immunosuppression and tolerance towards paternal and fetal antigens. In normal human pregnancy there is a relative suppression of Th1 type cytokines in response to lymphocytes, leading to a Th2 type response. In SLE, where a Th2 type response prevails, pregnancy may exacerbate the disease. This article reviews the alterations related to the immune response during normal pregnancy and in SLE patients.

  6. Om religion og evolution

    DEFF Research Database (Denmark)

    Geertz, Armin W.

    2011-01-01

    for kulturens kausale virkning på den menneskelige kognition og ikke mindst den hominine evolution. Ud fra, hvad vi ved om den menneskelige evolution, ses det, at den hominine evolution har en dybde, som sjældent medtænkes i teorier og hypoteser om den menneskelige evolution. Den menneskelige evolution er...

  7. Quasars and galactic evolution

    CERN Document Server

    Woltjer, L

    1978-01-01

    The evolution of quasars is discussed. It is noted that substantial clustering may be present at faint magnitudes. The relationship between quasar evolution and galactic evolution is considered. (4 refs).

  8. Nudging Evolution?

    Directory of Open Access Journals (Sweden)

    Katharine N. Farrell

    2013-12-01

    Full Text Available This Special Feature, "Nudging Evolution? Critical Exploration of the Potential and Limitations of the Concept of Institutional Fit for the Study and Adaptive Management of Social-Ecological Systems," aims to contribute toward the development of social theory and social research methods for the study of social-ecological system dynamics. Our objective is to help strengthen the academic discourse concerning if, and if so, how, to what extent, and in what concrete ways the concept of institutional "fit" might play a role in helping to develop better understanding of the social components of interlinkages between the socioeconomic-cultural and ecological dynamics of social-ecological systems. Two clearly discernible patterns provide a map of this Special Feature: (1 One pattern is the authors' positions regarding the place and role of normativity within their studies and assessment of institutional fit. Some place this at the center of their studies, exploring phenomena endogenous to the process of defining what constitutes institutional fit, whereas others take the formation of norms as a phenomenon exogenous to their study. (2 Another pattern is the type of studies presented: critiques and elaborations of the theory, methods for judging qualities of fit, and/or applied case studies using the concept. As a body of work, these contributions highlight that self-understanding of social-ecological place, whether explicit or implicit, constitutes an important part of the study object, i.e., the role of institutions in social-ecological systems, and that this is, at the same time, a crucial point of reference for the scholar wishing to evaluate what constitutes institutional fit and how it might be brought into being.

  9. Rivaroxaban in antiphospholipid syndrome (RAPS) protocol: a prospective, randomized controlled phase II/III clinical trial of rivaroxaban versus warfarin in patients with thrombotic antiphospholipid syndrome, with or without SLE.

    Science.gov (United States)

    Cohen, H; Doré, C J; Clawson, S; Hunt, B J; Isenberg, D; Khamashta, M; Muirhead, N

    2015-09-01

    The current mainstay of the treatment of thrombotic antiphospholipid syndrome (APS) is long-term anticoagulation with vitamin K antagonists (VKAs) such as warfarin. Non-VKA oral anticoagulants (NOACs), which include rivaroxaban, have been shown to be effective and safe compared with warfarin for the treatment of venous thromboembolism (VTE) in major phase III prospective, randomized controlled trials (RCTs), but the results may not be directly generalizable to patients with APS. The primary aim is to demonstrate, in patients with APS and previous VTE, with or without systemic lupus erythematosus (SLE), that the intensity of anticoagulation achieved with rivaroxaban is not inferior to that of warfarin. Secondary aims are to compare rates of recurrent thrombosis, bleeding and the quality of life in patients on rivaroxaban with those on warfarin. Rivaroxaban in antiphospholipid syndrome (RAPS) is a phase II/III prospective non-inferiority RCT in which eligible patients with APS, with or without SLE, who are on warfarin, target international normalized ratio (INR) 2.5 for previous VTE, will be randomized either to continue warfarin (standard of care) or to switch to rivaroxaban. Intensity of anticoagulation will be assessed using thrombin generation (TG) testing, with the primary outcome the percentage change in endogenous thrombin potential (ETP) from randomization to day 42. Other TG parameters, markers of in vivo coagulation activation, prothrombin fragment 1.2, thrombin antithrombin complex and D-dimer, will also be assessed. If RAPS demonstrates i) that the anticoagulant effect of rivaroxaban is not inferior to that of warfarin and ii) the absence of any adverse effects that cause concern with regard to the use of rivaroxaban, this would provide sufficient supporting evidence to make rivaroxaban a standard of care for the treatment of APS patients with previous VTE, requiring a target INR of 2.5. © The Author(s) 2015.

  10. Conformal invariance an introduction to loops, interfaces and stochastic Loewner evolution

    CERN Document Server

    Karevski, Dragi

    2012-01-01

    Conformal invariance has been a spectacularly successful tool in advancing our understanding of the two-dimensional phase transitions found in classical systems at equilibrium. This volume sharpens our picture of the applications of conformal invariance, introducing non-local observables such as loops and interfaces before explaining how they arise in specific physical contexts. It then shows how to use conformal invariance to determine their properties. Moving on to cover key conceptual developments in conformal invariance, the book devotes much of its space to stochastic Loewner evolution (SLE), detailing SLE’s conceptual foundations as well as extensive numerical tests. The chapters then elucidate SLE’s use in geometric phase transitions such as percolation or polymer systems, paying particular attention to surface effects. As clear and accessible as it is authoritative, this publication is as suitable for non-specialist readers and graduate students alike.

  11. Inlet Geomorphology Evolution

    Science.gov (United States)

    2015-04-01

    APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Inlet Geomorphology Evolution 5a. CONTRACT NUMBER 5b...Std Z39-18 Coastal Inlets Research Program Inlet Geomorphology Evolution The Inlet Geomorphology Evolution work unit of the CIRP evaluates

  12. Has Human Evolution Stopped?

    Directory of Open Access Journals (Sweden)

    Alan R. Templeton

    2010-07-01

    Full Text Available It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  13. Multicolour Observations, Inhomogeneity & Evolution

    OpenAIRE

    Hellaby, Charles

    2000-01-01

    We propose a method of testing source evolution theories that is independent of the effects of inhomogeneity, and thus complementary to other studies of evolution. It is suitable for large scale sky surveys, and the new generation of large telescopes. In an earlier paper it was shown that basic cosmological observations - luminosity versus redshift, area distance versus redshift and number counts versus redshift - cannot separate the effects of cosmic inhomogeneity, cosmic evolution and sourc...

  14. Oxygen evolution reaction catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  15. Stellar structure and evolution

    International Nuclear Information System (INIS)

    Kippernhahn, R.; Weigert, A.

    1990-01-01

    This book introduces the theory of the internal structure of stars and their evolution in time. It presents the basic physics of stellar interiors, methods for solving the underlying equations, and the most important results necessary for understanding the wide variety of stellar types and phenomena. The evolution of stars is discussed from their birth through normal evolution to possibly spectacular final stages. Chapters on stellar oscillations and rotation are included

  16. Adaptability and evolution.

    Science.gov (United States)

    Bateson, Patrick

    2017-10-06

    The capacity of organisms to respond in their own lifetimes to new challenges in their environments probably appeared early in biological evolution. At present few studies have shown how such adaptability could influence the inherited characteristics of an organism's descendants. In part, this has been because organisms have been treated as passive in evolution. Nevertheless, their effects on biological evolution are likely to have been important and, when they occurred, accelerated the pace of evolution. Ways in which this might have happened have been suggested many times since the 1870s. I review these proposals and discuss their relevance to modern thought.

  17. Interface dermatitis in skin lesions of Kikuchi-Fujimoto's disease: a histopathological marker of evolution into systemic lupus erythematosus?

    Science.gov (United States)

    Paradela, S; Lorenzo, J; Martínez-Gómez, W; Yebra-Pimentel, T; Valbuena, L; Fonseca, E

    2008-12-01

    Kikuchi's disease (KD) is a self-limiting histiocytic necrotizing lymphadenitis (HNL). Cutaneous manifestations are frequent and usually show histopathological findings similar to those observed in the involved lymph nodes. HNL with superposed histological features to KD has been described in patients with lupus erythematosus (LE), and a group of healthy patients previously reported as having HNL may evolve into LE after several months. Up to date, features to predict which HNL patients will have a self-limiting disease and which could develop LE have been not identified. In order to clarify the characteristics of skin lesions associated with KD, we report a case of HNL with evolution into systemic lupus erythematosus (SLE) and a review of previous reports of KD with cutaneous manifestations. A 17-year-old woman presented with a 4-month history of fever and generalised lymphadenopathy. A diagnosis of HNL was established based on a lymph node biopsy. One month later, she developed an erythematoedematous rash on her upper body, with histopathological findings of interface dermatitis. After 8 months, anti-nuclear antibodies (ANA) at titre of 1/320, anti-DNA-ds antibodies and marked decrease of complement levels were detected. During the following 2 years, she developed diagnostic criteria for SLE, with arthralgias, pleuritis, aseptic meningitis, haemolytic anaemia and lupus nephritis. To our knowledge, 27 cases of nodal and cutaneous KD have been reported, 9 of which later developed LE. In all these patients, the skin biopsy revealed interface dermatitis. Skin biopsy revealed a pattern of interface dermatitis in all reviewed KD cases, which evolved into LE. Even this histopathological finding was not previously considered significant; it might be a marker of evolution into LE.

  18. Evolution of Constructivism

    Science.gov (United States)

    Liu, Chu Chih; Chen, I Ju

    2010-01-01

    The contrast between social constructivism and cognitive constructivism are depicted in different ways in many studies. The purpose of this paper is to summarize the evolution of constructivism and put a focus on social constructivism from the perception of Vygotsky. This study provides a general idea of the evolution of constructivism for people…

  19. Evolution: Theory or Dogma?

    Science.gov (United States)

    Mayer, William V.

    In this paper the author examines the question of whether evolution is a theory or a dogma. He refutes the contention that there is a monolithic scientific conspiracy to present evolution as dogma and suggests that his own presentation might be more appropriately entitled "Creationism: Theory or Dogma." (PEB)

  20. Kognition, evolution og Bibel

    DEFF Research Database (Denmark)

    Jensen, Hans Jørgen Lundager

    2012-01-01

    En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)......En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)...

  1. Evolution for Young Victorians

    Science.gov (United States)

    Lightman, Bernard

    2012-01-01

    Evolution was a difficult topic to tackle when writing books for the young in the wake of the controversies over Darwin's "Origin of Species." Authors who wrote about evolution for the young experimented with different ways of making the complex concepts of evolutionary theory accessible and less controversial. Many authors depicted presented…

  2. Hydrogen evolution reaction catalyst

    Science.gov (United States)

    Subbaraman, Ram; Stamenkovic, Vojislav; Markovic, Nenad; Tripkovic, Dusan

    2016-02-09

    Systems and methods for a hydrogen evolution reaction catalyst are provided. Electrode material includes a plurality of clusters. The electrode exhibits bifunctionality with respect to the hydrogen evolution reaction. The electrode with clusters exhibits improved performance with respect to the intrinsic material of the electrode absent the clusters.

  3. Evolution, epigenetics and cooperation

    Indian Academy of Sciences (India)

    Explanations for biological evolution in terms of changes in gene frequencies refer to outcomes rather than process. Integrating epigenetic studies with older evolutionary theories has drawn attention to the ways in which evolution occurs. Adaptation at the level of the gene is givingway to adaptation at the level of the ...

  4. Evolution of complex dynamics

    Science.gov (United States)

    Wilds, Roy; Kauffman, Stuart A.; Glass, Leon

    2008-09-01

    We study the evolution of complex dynamics in a model of a genetic regulatory network. The fitness is associated with the topological entropy in a class of piecewise linear equations, and the mutations are associated with changes in the logical structure of the network. We compare hill climbing evolution, in which only mutations that increase the fitness are allowed, with neutral evolution, in which mutations that leave the fitness unchanged are allowed. The simple structure of the fitness landscape enables us to estimate analytically the rates of hill climbing and neutral evolution. In this model, allowing neutral mutations accelerates the rate of evolutionary advancement for low mutation frequencies. These results are applicable to evolution in natural and technological systems.

  5. Chemical evolution of galaxies

    CERN Document Server

    Matteucci, Francesca

    2012-01-01

    The term “chemical evolution of galaxies” refers to the evolution of abundances of chemical species in galaxies, which is due to nuclear processes occurring in stars and to gas flows into and out of galaxies. This book deals with the chemical evolution of galaxies of all morphological types (ellipticals, spirals and irregulars) and stresses the importance of the star formation histories in determining the properties of stellar populations in different galaxies. The topic is approached in a didactical and logical manner via galaxy evolution models which are compared with observational results obtained in the last two decades: The reader is given an introduction to the concept of chemical abundances and learns about the main stellar populations in our Galaxy as well as about the classification of galaxy types and their main observables. In the core of the book, the construction and solution of chemical evolution models are discussed in detail, followed by descriptions and interpretations of observations of ...

  6. Chromosomal Evolution in Chiroptera.

    Science.gov (United States)

    Sotero-Caio, Cibele G; Baker, Robert J; Volleth, Marianne

    2017-10-13

    Chiroptera is the second largest order among mammals, with over 1300 species in 21 extant families. The group is extremely diverse in several aspects of its natural history, including dietary strategies, ecology, behavior and morphology. Bat genomes show ample chromosome diversity (from 2n = 14 to 62). As with other mammalian orders, Chiroptera is characterized by clades with low, moderate and extreme chromosomal change. In this article, we will discuss trends of karyotypic evolution within distinct bat lineages (especially Phyllostomidae, Hipposideridae and Rhinolophidae), focusing on two perspectives: evolution of genome architecture, modes of chromosomal evolution, and the use of chromosome data to resolve taxonomic problems.

  7. Chromosomal Evolution in Chiroptera

    Directory of Open Access Journals (Sweden)

    Cibele G. Sotero-Caio

    2017-10-01

    Full Text Available Chiroptera is the second largest order among mammals, with over 1300 species in 21 extant families. The group is extremely diverse in several aspects of its natural history, including dietary strategies, ecology, behavior and morphology. Bat genomes show ample chromosome diversity (from 2n = 14 to 62. As with other mammalian orders, Chiroptera is characterized by clades with low, moderate and extreme chromosomal change. In this article, we will discuss trends of karyotypic evolution within distinct bat lineages (especially Phyllostomidae, Hipposideridae and Rhinolophidae, focusing on two perspectives: evolution of genome architecture, modes of chromosomal evolution, and the use of chromosome data to resolve taxonomic problems.

  8. Contemporary evolution strategies

    CERN Document Server

    Bäck, Thomas; Krause, Peter

    2013-01-01

    Evolution strategies have more than 50 years of history in the field of evolutionary computation. Since the early 1990s, many algorithmic variations of evolution strategies have been developed, characterized by the fact that they use the so-called derandomization concept for strategy parameter adaptation. Most importantly, the covariance matrix adaptation strategy (CMA-ES) and its successors are the key representatives of this group of contemporary evolution strategies. This book provides an overview of the key algorithm developments between 1990 and 2012, including brief descriptions of the a

  9. Weathering and landscape evolution

    Science.gov (United States)

    Turkington, Alice V.; Phillips, Jonathan D.; Campbell, Sean W.

    2005-04-01

    In recognition of the fundamental control exerted by weathering on landscape evolution and topographic development, the 35th Binghamton Geomorphology Symposium was convened under the theme of Weathering and Landscape Evolution. The papers and posters presented at the conference imparted the state-of-the-art in weathering geomorphology, tackled the issue of scale linkage in geomorphic studies and offered a vehicle for interdisciplinary communication on research into weathering and landscape evolution. The papers included in this special issue are encapsulated here under the general themes of weathering mantles, weathering and relative dating, weathering and denudation, weathering processes and controls and the 'big picture'.

  10. Dual phase evolution

    CERN Document Server

    Green, David G; Abbass, Hussein A

    2014-01-01

    This book explains how dual phase evolution operates in all these settings and provides a detailed treatment of the subject. The authors discuss the theoretical foundations for the theory, how it relates to other phase transition phenomena and its advantages in evolutionary computation and complex adaptive systems. The book provides methods and techniques to use this concept for problem solving. Dual phase evolution concerns systems that evolve via repeated phase shifts in the connectivity of their elements. It occurs in vast range of settings, including natural systems (species evolution, landscape ecology, geomorphology), socio-economic systems (social networks) and in artificial systems (annealing, evolutionary computing).

  11. Science, evolution, and creationism

    National Research Council Canada - National Science Library

    Committee on Revising Science and Creationism

    ... are more comfortable. In the book Science, Evolution, and Creationism, a group of experts assembled by the National Academy of Sciences and the Institute of Medicine explain the fundamental methods of science, document...

  12. Co-Evolution.

    Science.gov (United States)

    McGhee, Robert

    2002-01-01

    Discusses the role of techniques of DNA analysis in assessing the genetic relationships between various species. Focuses on wolf-dog evolution using DNA evidence and historical data about human/wolf-dog relationships. (DDR)

  13. Evolution of dosimetric phantoms

    International Nuclear Information System (INIS)

    Reddy, A.R.

    2010-01-01

    In this oration evolution of the dosimetric phantoms for radiation protection and for medical use is briefly reviewed. Some details of the development of Indian Reference Phantom for internal dose estimation are also presented

  14. Evolution of microbial pathogens

    National Research Council Canada - National Science Library

    DiRita, Victor J; Seifert, H. Steven

    2006-01-01

    ... A. Hogan vvi ■ CONTENTS 8. Evolution of Pathogens in Soil Rachel Muir and Man-Wah Tan / 131 9. Experimental Models of Symbiotic Host-Microbial Relationships: Understanding the Underpinnings of ...

  15. Evolution, epigenetics and cooperation.

    Science.gov (United States)

    Bateson, Patrick

    2014-04-01

    Explanations for biological evolution in terms of changes in gene frequencies refer to outcomes rather than process. Integrating epigenetic studies with older evolutionary theories has drawn attention to the ways in which evolution occurs. Adaptation at the level of the gene is givingway to adaptation at the level of the organism and higher-order assemblages of organisms. These ideas impact on the theories of how cooperation might have evolved. Two of the theories, i.e. that cooperating individuals are genetically related or that they cooperate for self-interested reasons, have been accepted for a long time. The idea that adaptation takes place at the level of groups is much more controversial. However, bringing together studies of development with those of evolution is taking away much of the heat in the debate about the evolution of group behaviour.

  16. Chemical evolution and life

    Directory of Open Access Journals (Sweden)

    Malaterre Christophe

    2015-01-01

    Full Text Available In research on the origins of life, the concept of “chemical evolution” aims at explaining the transition from non-living matter to living matter. There is however strong disagreement when it comes to defining this concept more precisely, and in particular with reference to a chemical form of Darwinian evolution: for some, chemical evolution is nothing but Darwinian evolution applied to chemical systems before life appeared; yet, for others, it is the type of evolution that happened before natural selection took place, the latter being the birthmark of living systems. In this contribution, I review the arguments defended by each side and show how both views presuppose a dichotomous definition of “life”.

  17. Evolution of interstellar grains

    International Nuclear Information System (INIS)

    Greenberg, J.M.

    1984-01-01

    The principal aim of this chapter is to derive the properties of interstellar grains as a probe of local physical conditions and as a basis for predicting such properties as related to infrared emissivity and radiative transfer which can affect the evolution of dense clouds. The first sections will develop the criteria for grain models based directly on observations of gas and dust. A summary of the chemical evolution of grains and gas in diffuse and dense clouds follows. (author)

  18. Evolution of Things

    OpenAIRE

    Eiben, A. E.; Ferreira, N.; Schut, M.; Kernbach, S.

    2011-01-01

    Evolution is one of the major omnipresent powers in the universe that has been studied for about two centuries. Recent scientific and technical developments make it possible to make the transition from passively understanding to actively mastering evolution. As of today, the only area where human experimenters can design and manipulate evolutionary processes in full is that of Evolutionary Computing, where evolutionary processes are carried out in a digital space, inside computers, in simulat...

  19. Manipulation of quantum evolution

    Science.gov (United States)

    Cabera, David Jose Fernandez; Mielnik, Bogdan

    1994-01-01

    The free evolution of a non-relativistic charged particle is manipulated using time-dependent magnetic fields. It is shown that the application of a programmed sequence of magnetic pulses can invert the free evolution process, forcing an arbitrary wave packet to 'go back in time' to recover its past shape. The possibility of more general operations upon the Schrodinger wave packet is discussed.

  20. Chemical evolution of galaxies

    International Nuclear Information System (INIS)

    Matteucci, F.; Consiglio Nazionale delle Ricerche, Frascati

    1989-01-01

    In principle, a good model of galactic chemical evolution should fulfil the majority of well established observational constraints. The goal of this paper is to review the observational data together with the existing chemical evolution models for the Milky Way (the disk), Blue Compact and Elliptical galaxies and to show how well the models can account for the observations. Some open problems and future prospects are also discussed. (author)

  1. Developing theology for evolution

    Directory of Open Access Journals (Sweden)

    Chris Wiltsher

    2013-07-01

    Full Text Available This speculative paper explores one idea for approaching some of the problems which arise when the doctrines of Christian theology meet the current scientific understanding of evolution through natural selection. The main suggestion is that Christian theology should relax the requirement that God controls everything. Some implications of this move are explored, with a brief look at how similar ideas might be of use for non-Christian religions entering into dialogue with the theory of evolution

  2. Software evolution with XVCL

    DEFF Research Database (Denmark)

    Zhang, Weishan; Jarzabek, Stan; Zhang, Hongyu

    2004-01-01

    This chapter introduces software evolution with XVCL (XML-based Variant Configuration Language), which is an XML-based metaprogramming technique. As the software evolves, a large number of variants may arise, especially whtn such kinds of evolutions are related to multiple platforms as shown in our...... case study. Handling variants and tracing the impact of variants across the development lifecycle is a challenge. This chapter shows how we can maintain different versions of software in a reuse-based way....

  3. Evolution of massive stars

    International Nuclear Information System (INIS)

    Loore, C. de

    1984-01-01

    The evolution of stars with masses larger than 15 sun masses is reviewed. These stars have large convective cores and lose a substantial fraction of their matter by stellar wind. The treatment of convection and the parameterisation of the stellar wind mass loss are analysed within the context of existing disagreements between theory and observation. The evolution of massive close binaries and the origin of Wolf-Rayet Stars and X-ray binaries is also sketched. (author)

  4. Divergent Cumulative Cultural Evolution

    OpenAIRE

    Marriott, Chris; Chebib, Jobran

    2016-01-01

    Divergent cumulative cultural evolution occurs when the cultural evolutionary trajectory diverges from the biological evolutionary trajectory. We consider the conditions under which divergent cumulative cultural evolution can occur. We hypothesize that two conditions are necessary. First that genetic and cultural information are stored separately in the agent. Second cultural information must be transferred horizontally between agents of different generations. We implement a model with these ...

  5. The theory of evolution

    Directory of Open Access Journals (Sweden)

    Oleg Bazaluk

    2015-06-01

    Full Text Available The book The Theory of Evolution: from the Space Vacuum to Neural Ensembles and Moving Forward, an edition of 100 copies, was published in Russian language, in December 2014 in Kiev. Its Russian version is here: http://en.bazaluk.com/journals.html. Introduction, Chapter 10 and Conclusion published in English for the first time. Since 2004 author have been researching in the field of theory of Evolution, Big History. The book was written on the base of analysis of more than 2000 primary sources of this research topic. The volume is 90,000 words (with Reference. The book is for a wide range of professionals, from students to professors and researchers working in the fields of: philosophical anthropology, philosophy, Big History, cosmology, biology, neuroscience and etc. In the book, the author defines the evolution as continuous and nonlinear complication of the structure of matter, the types of interaction and environments; analyzes existing in modern science and philosophy approaches to the research of the process of evolution, degree of development of the factors and causes of evolution. Unifying interdisciplinary researches of evolution in cosmology, biology, neuroscience and philosophy, the author presents his vision of the model of «Evolving Matter», which allows us to consider not only the laws of transition of space vacuum in neural ensembles but also to see our Universe as a complication, heterogeneous organization. Interdisciplinary amount of information on the theory of evolution is systematized and a new method of world perception is proposed in the book.

  6. Evolution: from cosmogenesis to biogenesis

    International Nuclear Information System (INIS)

    Lukacs, B.; Berczi, Sz.; Molnar, I.; Paal, G.

    1990-11-01

    The volume contains the material of an interdisciplinary evolution symposium. The purpose was to shed some light on possible connections between steps of evolution of matter on different levels of organisation. The topics involved are as follow: cosmogenesis; galactic and stellar evolution; formation and evolution of the solar system; global atmospheric and tectonic changes of Earth; viral evolution; phylogeny and evolution of terrestrial life; evolution of neural system; hominization. The material also includes some discussions of the underlying phenomena and laws of nature. (author)

  7. Estudo retrospectivo de 76 fetos de mães com lúpus eritematoso sistêmico (LES Retrospective study of 76 fetus of mother with systemic lupus erythematosus (SLE

    Directory of Open Access Journals (Sweden)

    Marcela Ushida

    2004-10-01

    prevalência de perda fetal (aborto e óbito intra-uterino, entretanto, a freqüência de prematuridade foi maior que a média referida em outros trabalhos. Manifestações hematológicas do lúpus neonatal, como leucopenia e plaquetopenia foram observadas em freqüência maior do que a referida na literatura. Por serem transitórias e assintomáticas, estas alterações podem ter sido subdiagnosticadas.OBJECTIVE: to evaluate the frequency of neonatal lupus, prematurity, fetal loss, and low weight in pregnancies of SLE patients attended at a tertiary health service. MEHTODS: it is a retrospective study evaluating all SLE patients attended at obstetric center of Hospital São Paulo/Unifesp/EPM from November, 1991 to April, 2003. The mother and children's clinical and laboratory data were obtained reviewing medical records. RESULTS: sixty women and 75 pregnancies were identified. The mother age average during the pregnancies was 27.1±6.1 years old and the median of disease duration was 48 months. Two patients needed to be submitted to dialysis during the pregnancy. Sixty-three patients used prednisone, 4 received methilprednisolone pulsetherapy and 2 received azathioprine during the pregnancy. During the first trimester of pregnancy, 6 patients received diphosphate chloroquine and 2 received hidroxychloroquine. Two patients unknowing pregnancy received pulse of cyclophosphamide and another one had used methotrexate and both presented spontaneous abortion. It was observed 13 cases of intrauterine death and 7 abortions. Preterm birth occurred in 57% of pregnancies and the average duration of gestation was 35 weeks. The mean weight of the newborns was 2,332±961g (ranging from 525 to 3,620g. Five cases of neonatal lupus were identified (8,9%. One with congenital heart block (CHB had intrauterine death at the 29th week of gestation, had 3 babies with thrombocytopenia associated with anti-Ro/SSA antibodies and one with neutropenia associated with anti-RNP antibody. Excepting

  8. Lossless Conditional Schema Evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Bøhlen, Michael Hanspeter

    2003-01-01

    The paper considers conditional schema evolution, where schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation change some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples and the reco......The paper considers conditional schema evolution, where schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation change some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples...... and the recorded schema of tuples is at the core of a DBMS that supports schema evolution. We propose to keep track of schema mismatches at the level of individual tuples, and prove that conditionally evolving schemas, in contrast to current commercial database systems, are lossless when the schema evolves...

  9. Evolution of Scale Worms

    DEFF Research Database (Denmark)

    Gonzalez, Brett Christopher

    ) caves, and the interstitium, recovering six monophyletic clades within Aphroditiformia: Acoetidae, Aphroditidae, Eulepethidae, Iphionidae, Polynoidae, and Sigalionidae (inclusive of the former ‘Pisionidae’ and ‘Pholoidae’), respectively. Tracing of morphological character evolution showed a high degree...... of adaptability and convergent evolution between relatively closely related scale worms. While some morphological and behavioral modifications in cave polynoids reflected troglomorphism, other modifications like eye loss were found to stem from a common ancestor inhabiting the deep sea, further corroborating...... the deep sea ancestry of scale worm cave fauna. In conclusion, while morphological characterization across Aphroditiformia appears deceptively easy due to the presence of elytra, convergent evolution during multiple early radiations across wide ranging habitats have confounded our ability to reconstruct...

  10. Education and Evolution

    DEFF Research Database (Denmark)

    Hjermitslev, Hans Henrik

    2015-01-01

    Herbert Spencer’s ideas were first introduced to a Scandinavian audience in the early 1870s when the Danish philosopher Harald Høffding published and lectured on his evolutionary philosophy. At this time, Høffding also played an important role in disseminating Charles Darwin’s theory of evolution...... and in discussing the philosophical consequences of an evolutionary worldview. In the late 1870s and 1880s several of Spencer’s works were translated into Danish and Swedish and he became a household name among liberal intellectuals who primarily discussed his views on education and evolution. His most influential...... known foreign thinkers in the general public at the time of his death in 1903. Moreover, in the decades around 1900 Spencer’s thoughts on education were part of the curricula at many colleges of education. Spencer’s ideas on evolution and education were thus widely circulated and positively received...

  11. Quantum evolution across singularities

    International Nuclear Information System (INIS)

    Craps, Ben; Evnin, Oleg

    2008-01-01

    Attempts to consider evolution across space-time singularities often lead to quantum systems with time-dependent Hamiltonians developing an isolated singularity as a function of time. Examples include matrix theory in certain singular time-dependent backgounds and free quantum fields on the two-dimensional compactified Milne universe. Due to the presence of the singularities in the time dependence, the conventional quantum-mechanical evolution is not well-defined for such systems. We propose a natural way, mathematically analogous to renormalization in conventional quantum field theory, to construct unitary quantum evolution across the singularity. We carry out this procedure explicitly for free fields on the compactified Milne universe and compare our results with the matching conditions considered in earlier work (which were based on the covering Minkowski space)

  12. Boussinesq evolution equations

    DEFF Research Database (Denmark)

    Bredmose, Henrik; Schaffer, H.; Madsen, Per A.

    2004-01-01

    This paper deals with the possibility of using methods and ideas from time domain Boussinesq formulations in the corresponding frequency domain formulations. We term such frequency domain models "evolution equations". First, we demonstrate that the numerical efficiency of the deterministic...... Boussinesq evolution equations of Madsen and Sorensen [Madsen, P.A., Sorensen, O.R., 1993. Bound waves and triad interactions in shallow water. Ocean Eng. 20 359-388] can be improved by using Fast Fourier Transforms to evaluate the nonlinear terms. For a practical example of irregular waves propagating over...... a submerged bar, it is demonstrated that evolution equations utilising FFT can be solved around 100 times faster than the corresponding time domain model. Use of FFT provides an efficient bridge between the frequency domain and the time domain. We utilise this by adapting the surface roller model for wave...

  13. Software architecture evolution

    DEFF Research Database (Denmark)

    Barais, Olivier; Le Meur, Anne-Francoise; Duchien, Laurence

    2008-01-01

    Software architectures must frequently evolve to cope with changing requirements, and this evolution often implies integrating new concerns. Unfortunately, when the new concerns are crosscutting, existing architecture description languages provide little or no support for this kind of evolution....... The software architect must modify multiple elements of the architecture manually, which risks introducing inconsistencies. This chapter provides an overview, comparison and detailed treatment of the various state-of-the-art approaches to describing and evolving software architectures. Furthermore, we discuss...... one particular framework named Tran SAT, which addresses the above problems of software architecture evolution. Tran SAT provides a new element in the software architecture descriptions language, called an architectural aspect, for describing new concerns and their integration into an existing...

  14. Validering av Evolution 220

    OpenAIRE

    Krakeli, Tor-Arne

    2013-01-01

    - Det har blitt kjøpt inn et nytt spektrofotometer (Evolution 220, Thermo Scientific) til BioLab Nofima. I den forbindelsen har det blitt utført en validering som involverer kalibreringsstandarder fra produsenten og en test på normal distribusjon (t-test) på to metoder (Total fosfor, Tryptofan). Denne valideringen fant Evolution 220 til å være et akseptabelt alternativ til det allerede benyttede spektrofotometeret (Helios Beta). På bakgrunn av noen instrumentbegrensninger må de aktuelle an...

  15. TMDs: Evolution, modeling, precision

    Directory of Open Access Journals (Sweden)

    D’Alesio Umberto

    2015-01-01

    Full Text Available The factorization theorem for qT spectra in Drell-Yan processes, boson production and semi-inclusive deep inelastic scattering allows for the determination of the non-perturbative parts of transverse momentum dependent parton distribution functions. Here we discuss the fit of Drell-Yan and Z-production data using the transverse momentum dependent formalism and the resummation of the evolution kernel. We find a good theoretical stability of the results and a final χ2/points ≲ 1. We show how the fixing of the non-perturbative pieces of the evolution can be used to make predictions at present and future colliders.

  16. Emergence and Evolution

    DEFF Research Database (Denmark)

    Bullwinkle, Tammy J; Ibba, Michael

    2013-01-01

    ancestor and as such they provide insights into the evolution and development of the extant genetic code. Although the aaRSs have long been viewed as a highly conserved group of enzymes, findings within the last couple of decades have started to demonstrate how diverse and versatile these enzymes really...... are. Beyond their central role in translation, aaRSs and their numerous homologs have evolved a wide array of alternative functions both inside and outside translation. Current understanding of the emergence of the aaRSs, and their subsequent evolution into a functionally diverse enzyme family...

  17. Evolution 2.0

    DEFF Research Database (Denmark)

    Andersen, Casper; Bek-Thomsen, Jakob; Clasen, Mathias

    2013-01-01

    Studies in the history of science and education have documented that the reception and understanding of evolutionary theory is highly contingent on local factors such as school systems, cultural traditions, religious beliefs, and language. This has important implications for teaching evolution...... audiences readily available. As more and more schools require teachers to use low cost or free web-based materials, in the research community we need to take seriously how to facilitate that demand in communication strategies on evolution. This article addresses this challenge by presenting the learning...

  18. Methylome evolution in plants.

    Science.gov (United States)

    Vidalis, Amaryllis; Živković, Daniel; Wardenaar, René; Roquis, David; Tellier, Aurélien; Johannes, Frank

    2016-12-20

    Despite major progress in dissecting the molecular pathways that control DNA methylation patterns in plants, little is known about the mechanisms that shape plant methylomes over evolutionary time. Drawing on recent intra- and interspecific epigenomic studies, we show that methylome evolution over long timescales is largely a byproduct of genomic changes. By contrast, methylome evolution over short timescales appears to be driven mainly by spontaneous epimutational events. We argue that novel methods based on analyses of the methylation site frequency spectrum (mSFS) of natural populations can provide deeper insights into the evolutionary forces that act at each timescale.

  19. Chemical evolution of galaxies

    International Nuclear Information System (INIS)

    Vigroux, Laurent

    1979-01-01

    This research thesis addresses theories on the chemical evolution of galaxies which aim at explaining abundances of different elements in galaxies, and more particularly aims at improving the model by modifying hypotheses. After a description of the simple model and of its uncertainties, the author shows how it is possible to understand the evolution of the main elements. Predictions obtained with this model are then compared with the present knowledge on galaxies by considering them according to an increasing complexity: Sun's neighbourhood, our galaxy, other spiral galaxies, elliptical galaxies, and finally galaxy clusters. A specific attention is given to irregular galaxies which are the simplest systems [fr

  20. Evolution of housing

    NARCIS (Netherlands)

    Slob, C.; Mohammadi, S.; Geraedts, R.P.

    2012-01-01

    ‘Perfection means something is complete and stands still and what stands still doesn’t change or evolve and is automatically dead. Everything in the universe changes, evolution implies that the creation is not complete hence the possibility of evolving’ (Osho, 1985). Our society and economy are

  1. The Evolution of Empathy

    Science.gov (United States)

    Hackney, Harold

    1978-01-01

    Therapeutic empathy has been an often-used construct by counseling professionals. Through that usage, the term has evolved in meaning and significance from its original presentation by Carl Rogers. This article traces that evolution by identifying its users and contributors over the past 20 years. (Author)

  2. Evolution Perception with Metaphors

    Science.gov (United States)

    Yilmaz, Fatih

    2016-01-01

    The main objective of this research is to find out how the teacher candidates who graduated from the Faculty of Theology and study in pedagogical formation program perceive the theory of evolution. Having a descriptive characteristic, this research is conducted with 63 Faculty of Theology graduate teacher candidates of which 36 is women and 27 is…

  3. Evolution of Business Models

    DEFF Research Database (Denmark)

    Antero, Michelle C.; Hedman, Jonas; Henningsson, Stefan

    2013-01-01

    The ERP industry has undergone dramatic changes over the past decades due to changing market demands, thereby creating new challenges and opportunities, which have to be managed by ERP vendors. This paper inquires into the necessary evolution of business models in a technology-intensive industry (e...

  4. Evolution of subsidiary competences

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Pedersen, Torben; Dhanaraj, Charles

    of competitive advantage of nations, we hypothesize the contingencies under which heterogeneity in host environments influences subsidiary competence configuration. We test our model with data from more than 2,000 subsidiaries in seven Western European countries. Our results provide new insights on the evolution...

  5. Titan Polar Landscape Evolution

    Science.gov (United States)

    Moore, Jeffrey M.

    2016-01-01

    With the ongoing Cassini-era observations and studies of Titan it is clear that the intensity and distribution of surface processes (particularly fluvial erosion by methane and Aeolian transport) has changed through time. Currently however, alternate hypotheses substantially differ among specific scenarios with respect to the effects of atmospheric evolution, seasonal changes, and endogenic processes. We have studied the evolution of Titan's polar region through a combination of analysis of imaging, elevation data, and geomorphic mapping, spatially explicit simulations of landform evolution, and quantitative comparison of the simulated landscapes with corresponding Titan morphology. We have quantitatively evaluated alternate scenarios for the landform evolution of Titan's polar terrain. The investigations have been guided by recent geomorphic mapping and topographic characterization of the polar regions that are used to frame hypotheses of process interactions, which have been evaluated using simulation modeling. Topographic information about Titan's polar region is be based on SAR-Topography and altimetry archived on PDS, SAR-based stereo radar-grammetry, radar-sounding lake depth measurements, and superposition relationships between geomorphologic map units, which we will use to create a generalized topographic map.

  6. Kinship and Human Evolution

    DEFF Research Database (Denmark)

    Bergendorff, Steen

    This book offers a exiting new explanation of human evolution. Based on insight from Anthropology is shows that human became 'cultured' beings capable of symbolic thought by developing rasting kinship based between groups that could not other wise survive in the harah climate condition during...

  7. Software Architecture Evolution

    Science.gov (United States)

    Barnes, Jeffrey M.

    2013-01-01

    Many software systems eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the causes, architecture evolution is commonplace in real-world software projects. Today's software architects, however,…

  8. Open-Ended Evolution

    DEFF Research Database (Denmark)

    Taylor, Tim; Bedau, Mark A.; Channon, Alastair

    2016-01-01

    This report describes the First Workshop on Open-Ended Evolution: Recent Progress and Future Milestones (OEE1), held during the ECAL 2015 conference at the University of York, U.K., in July 2015. We briefly summarise the content of the talks and discussions and the workshop, and provide links...

  9. The Evolution of Galaxies

    Czech Academy of Sciences Publication Activity Database

    Palouš, Jan

    2007-01-01

    Roč. 17, - (2007), s. 34-40 ISSN 1220-5168. [Heliospere and galaxy. Sinaia, 03.05.2007-05.05.2007] R&D Projects: GA MŠk(CZ) LC06014 Institutional research plan: CEZ:AV0Z10030501 Keywords : ISM structure * stars formation * evolution of galaxies Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  10. MDSplus evolution continues

    International Nuclear Information System (INIS)

    Manduchi, G.; Fredian, T.W.; Stillerman, J.A.

    2012-01-01

    Highlights: ► The paper describes the recent evolution of the MDSplus data system. ► It presents a Use Case to explain MDSplus expressions. ► It presents the features recently developed. ► It presents the features under development. - Abstract: The MDSplus data system has been in operation on several fusion machines since 1991 and it is currently in use at over 30 sites spread over 5 continents. A consequence is the extensive feedback provided by the MDSplus user community for bug fixes and improvements and therefore the evolution of MDSplus is keeping pace with the evolution in data acquisition and management techniques. In particular, the recent evolution of MDSplus has been driven by the change in the paradigm for data acquisition in long lasting plasma discharges, where a sustained data stream is transferred from the acquisition devices into the database. Several new features are currently available or are being implemented in MDSplus. The features already implemented include a comprehensive Object-Oriented interface to the system, the python support for data acquisition devices and the full integration in EPICS. Work is in progress for the integration of multiple protocols and security systems in remote data access, a new high level data view layer and a new version of the jScope tool for online visualization and the optimized visualization of very large signals.

  11. Common envelope evolution

    NARCIS (Netherlands)

    Taam, Ronald E.; Ricker, Paul M.

    2010-01-01

    The common envelope phase of binary star evolution plays a central role in many evolutionary pathways leading to the formation of compact objects in short period systems. Using three dimensional hydrodynamical computations, we review the major features of this evolutionary phase, focusing on the

  12. Methylome evolution in plants

    NARCIS (Netherlands)

    Vidalis, Amaryllis; Živković, Daniel; Wardenaar, René; Roquis, David; Tellier, Aurélien; Johannes, Frank

    2016-01-01

    Despite major progress in dissecting the molecular pathways that control DNA methylation patterns in plants, little is known about the mechanisms that shape plant methylomes over evolutionary time. Drawing on recent intra- and interspecific epigenomic studies, we show that methylome evolution over

  13. The Evolution of Darwinism.

    Science.gov (United States)

    Stebbins, G. Ledyard; Ayala, Francisco J.

    1985-01-01

    Recent developments in molecular biology and new interpretations of the fossil record are gradually altering and adding to Charles Darwin's theory, which has been the standard view of the process of evolution for 40 years. Several of these developments and interpretations are identified and discussed. (JN)

  14. Darwinism: Evolution or Revolution?

    Science.gov (United States)

    Holt, Niles R.

    1989-01-01

    Maintains that Darwin's theory of evolution was more than a science versus religion debate; rather it was a revolutionary concept that influenced numerous social and political ideologies and movements throughout western history. Traces the impact of Darwin's work historically, utilizing a holistic approach. (RW)

  15. Modeling shoreface profile evolution

    NARCIS (Netherlands)

    Stive, M.J.F.; De Vriend, H.J.

    1995-01-01

    Current knowledge of hydro-, sediment and morpho-dynamics in the shoreface environment is insufficient to undertake shoreface-profile evolution modelling on the basis of first physical principles. We propose a simple, panel-type model to map observed behaviour. The internal dynamics are determined

  16. Modelling shoreface profile evolution

    NARCIS (Netherlands)

    Stive, Marcel J.F.; de Vriend, Huib J.

    1995-01-01

    Current knowledge of hydro-, sediment and morpho-dynamics in the shoreface environment is insufficient to undertake shoreface-profile evolution modelling on the basis of first physical principles. We propose a simple, panel-type model to map observed behaviour. The internal dynamics are determined

  17. The Idea of Evolution

    Science.gov (United States)

    Mathison, Jane

    1976-01-01

    The idea of evolution is examined in a historical perspective in this article. Considerable discussion is given to the works of Lamarck and Darwin. The evolutionary process is also examined with respect to philosophy, art and music history, and man's place in nature. References are included. (MA)

  18. Evolution and Education

    Science.gov (United States)

    Washburn, S. L.

    1974-01-01

    Education should give an understanding of the world and of man, as well as offer the vocational training, at which the university excells. The use of case studies to provide immediate insight into advancing knowledge and the study of evolution have important instructional and educational implication for the goal of understanding man. (JH)

  19. Evolution, Insight and Truth?

    Science.gov (United States)

    Newall, Emma

    2017-01-01

    Evolution has been positioned at the centre of conflict between scientific and religious explanations of the workings of the world. However, little research has examined other possible reasons for some people rejecting scientific explanations. The author's research indicates that for some people, irrespective of faith, the ideas associated with…

  20. Evolution. Teacher's Guide.

    Science.gov (United States)

    Bershad, Carol

    This teacher's guide was developed to assist teachers in the use of multimedia resources for the Public Broadcasting System (PBS) program, "Evolution." Each unit uses an inquiry-based approach to meet the National Science Education Standards. Units include: (1) "What is the Nature of Science?"; (2) "Who Was Charles Darwin?"; (3) "What is the…

  1. Relations between the galactic evolution and the stellar evolution

    International Nuclear Information System (INIS)

    Audouze, J.

    1984-01-01

    After a quick definition of the galactic evolution and a summary of the basic ingredients (namely the abundances of the chemical elements observed in different astrophysical sites), the parameters directly related to the stellar evolution which govern the galactic evolution are outlined. They are the rates of star formation, the initial mass functions and the various nucleosynthetic yields. The 'classical' models of chemical evolution of galaxies are then briefly recalled. Finally, attention is drawn to three recent contributions concerning both the galactic evolution and the stellar evolution. They are (i) some prediction of the rate of star formation for low mass stars made from the planetary nebula abundance distribution (ii) the chemical evolution of C, O and Fe and (iii) the chemical evolution of the galactic interstellar medium. (Auth.)

  2. Effective Strategies for Teaching Evolution: The Primary Evolution Project

    Science.gov (United States)

    Hatcher, Chris

    2015-01-01

    When Chris Hatcher joined the Primary Evolution Project team at the University of Reading, his goal was to find effective strategies to teach evolution in a way that keeps children engaged and enthused. Hatcher has collaborated with colleagues at the University's Institute of Education to break the evolution unit down into distinct topics and…

  3. Viral Evolution Core | FNLCR Staging

    Science.gov (United States)

    Brandon F. Keele, Ph.D. PI/Senior Principal Investigator, Retroviral Evolution Section Head, Viral Evolution Core Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research Frederick, MD 21702-1201 Tel: 301-846-173

  4. The physics of evolution

    Science.gov (United States)

    Eigen, Manfred

    1988-12-01

    The Darwinian concept of evolution through natural selection has been revised and put on a solid physical basis, in a form which applies to self-replicable macromolecules. Two new concepts are introduced: sequence space and quasi-species. Evolutionary change in the DNA- or RNA-sequence of a gene can be mapped as a trajectory in a sequence space of dimension ν, where ν corresponds to the number of changeable positions in the genomic sequence. Emphasis, however, is shifted from the single surviving wildtype, a single point in the sequence space, to the complex structure of the mutant distribution that constitutes the quasi-species. Selection is equivalent to an establishment of the quasi-species in a localized region of sequence space, subject to threshold conditions for the error rate and sequence length. Arrival of a new mutant may violate the local threshold condition and thereby lead to a displacement of the quasi-species into a different region of sequence space. This transformation is similar to a phase transition; the dynamical equations that describe the quase-species have been shown to be analogous to those of the two-dimensional Ising model of ferromagnetism. The occurrence of a selectively advantageous mutant is biased by the particulars of the quasi-species distribution, whose mutants are populated according to their fitness relative to that of the wild-type. Inasmuch as fitness regions are connected (like mountain ridges) the evolutionary trajectory is guided to regions of optimal fitness. Evolution experiments in test tubes confirm this modification of the simple chance and law nature of the Darwinian concept. The results of the theory can also be applied to the construction of a machine that provides optimal conditions for a rapid evolution of functionally active macromolecules. An introduction to the physics of molecular evolution by the author has appeared recently.1 Detailed studies of the kinetics and mechanisms of replication of RNA, the most

  5. Toward Documentation of Program Evolution

    DEFF Research Database (Denmark)

    Vestdam, Thomas; Nørmark, Kurt

    2005-01-01

    The documentation of a program often falls behind the evolution of the program source files. When this happens it may be attractive to shift the documentation mode from updating the documentation to documenting the evolution of the program. This paper describes tools that support the documentatio....... It is concluded that our approach can help revitalize older documentation, and that discovery of the fine grained program evolution steps help the programmer in documenting the evolution of the program....

  6. Expanding the Understanding of Evolution

    Science.gov (United States)

    Musante, Susan

    2011-01-01

    Originally designed for K-12 teachers, the Understanding Evolution (UE) Web site ("www.understandingevolution.org") is a one-stop shop for all of a teacher's evolution education needs, with lesson plans, teaching tips, lists of common evolution misconceptions, and much more. However, during the past five years, the UE project team learned that…

  7. Inlet Geomorphology Evolution Work Unit

    Science.gov (United States)

    2015-10-30

    Coastal Inlets Research Program Inlet Geomorphology Evolution Work Unit The Inlet Geomorphology Evolution work unit of the CIRP develops methods...morphologic response. Presently, the primary tool of the Inlet Geomorphology Evolution work unit is the Sediment Mobility Tool (SMT), which allows the user

  8. Evolution and transitions in complexity

    NARCIS (Netherlands)

    Jagers op Akkerhuis, Gerard A.J.M.

    2016-01-01

    This book discusses several recent theoretic advancements in interdisciplinary and transdisciplinary integration in the field of evolution. While exploring novel views, the text maintains a close link with one of the most broadly held views on evolution, namely that of "Darwinian evolution." This

  9. The evolution of dinosaurs.

    Science.gov (United States)

    Sereno, P C

    1999-06-25

    The ascendancy of dinosaurs on land near the close of the Triassic now appears to have been as accidental and opportunistic as their demise and replacement by therian mammals at the end of the Cretaceous. The dinosaurian radiation, launched by 1-meter-long bipeds, was slower in tempo and more restricted in adaptive scope than that of therian mammals. A notable exception was the evolution of birds from small-bodied predatory dinosaurs, which involved a dramatic decrease in body size. Recurring phylogenetic trends among dinosaurs include, to the contrary, increase in body size. There is no evidence for co-evolution between predators and prey or between herbivores and flowering plants. As the major land masses drifted apart, dinosaurian biogeography was molded more by regional extinction and intercontinental dispersal than by the breakup sequence of Pangaea.

  10. Evolution of energy structures

    International Nuclear Information System (INIS)

    Nifenecker, H.

    2005-01-01

    Because of the big inertia and long time constants of energy systems, their long-time behaviour is mainly determined by their present day state and by the trends of their recent evolution. For this reason, it is of prime importance to foresee the evolution of the different energy production sources which may play an important role in the future. A status of the world energy consumption and production is made first using the energy statistics of the IEA. Then, using the trends observed since 1973, the consequences of a simple extrapolation of these trends is examined. Finally, the scenarios of forecasting of energy structures, like those supplied by the International institute for applied systems analysis (IIASA) are discussed. (J.S.)

  11. Evolution of Mobile Applications

    Directory of Open Access Journals (Sweden)

    Phongtraychack Anachack

    2018-01-01

    Full Text Available Currently, we can see the rapid evolution of mobile technology, which involves mobile communication, mobile hardware, and mobile software. Features of mobile phones largely depend on software. In contemporary information and communication age [1–4], mobile application is one of the most concerned and rapidly developing areas. At the same time, the development of mobile application undergoes great changes with the introduction of new software, service platforms and software development kits (SDK. These changes lead to appearance of many new service platforms such as Google with Android and Apple with iOS. This article presents the information about the evolution of mobile application, gives some statistical data on the past and present situation, demonstrates how individual users of mobile devices can benefit, and shows how mobile applications affect society from the ethical perspective.

  12. Evolution to Autonomy

    Directory of Open Access Journals (Sweden)

    Horace Lockwood Fairlamb

    2007-08-01

    Full Text Available Since both modern moral theory and evolutionary theory arose in the shadow of Newtonian and Humean conceptions of nature, debates about evolutionary ethics have typically been vexed by deeper problems with the nature of evolution itself as well as meta-ethical questions about the link between facts and values. Humean skepticism and mechanistic selectionism have recently coincided in postmodern attacks on essentialism,on meta-narratives of progress, on models of human nature, and on moral collectivism. Against this most recent wave of skepticism, however, contemporary reconstructions of evolution in light of complex systems science suggest useful ways of reinterpreting both evolutionary causation, the biology of human nature, and their implications for ethics.

  13. Galaxy formation and evolution

    CERN Document Server

    Mo, Houjun; White, Simon

    2010-01-01

    The rapidly expanding field of galaxy formation lies at the interface between astronomy, particle physics, and cosmology. Covering diverse topics from these disciplines, all of which are needed to understand how galaxies form and evolve, this book is ideal for researchers entering the field. Individual chapters explore the evolution of the Universe as a whole and its particle and radiation content; linear and nonlinear growth of cosmic structure; processes affecting the gaseous and dark matter components of galaxies and their stellar populations; the formation of spiral and elliptical galaxies; central supermassive black holes and the activity associated with them; galaxy interactions; and the intergalactic medium. Emphasizing both observational and theoretical aspects, this book provides a coherent introduction for astronomers, cosmologists, and astroparticle physicists to the broad range of science underlying the formation and evolution of galaxies.

  14. Managing Software Process Evolution

    DEFF Research Database (Denmark)

    This book focuses on the design, development, management, governance and application of evolving software processes that are aligned with changing business objectives, such as expansion to new domains or shifting to global production. In the context of an evolving business world, it examines...... the complete software process lifecycle, from the initial definition of a product to its systematic improvement. In doing so, it addresses difficult problems, such as how to implement processes in highly regulated domains or where to find a suitable notation system for documenting processes, and provides...... essential insights and tips to help readers manage process evolutions. And last but not least, it provides a wealth of examples and cases on how to deal with software evolution in practice. Reflecting these topics, the book is divided into three parts. Part 1 focuses on software business transformation...

  15. Instability and star evolution

    International Nuclear Information System (INIS)

    Mirzoyan, L.V.

    1981-01-01

    The observational data are discussed which testify that the phenomena of dynamical instability of stars and stellar systems are definite manifestations of their evolution. The study of these phenomena has shown that the instability is a regular phase of stellar evolution. It has resulted in the recognition of the most important regularities of the process of star formation concerning its nature. This became possible due to the discovery in 1947 of stellar associations in our Galaxy. The results of the study of the dynamical instability of stellar associations contradict the predictions of classical hypothesis of stellar condensation. These data supplied a basis for a new hypothesis on the formation of stars and nebulae by the decay of superdense protostars [ru

  16. Evolution of clustered storage

    CERN Multimedia

    CERN. Geneva; Van de Vyvre, Pierre

    2007-01-01

    The session actually featured two presentations: * Evolution of clustered storage by Lance Hukill, Quantum Corporation * ALICE DAQ - Usage of a Cluster-File System: Quantum StorNext by Pierre Vande Vyvre, CERN-PH the second one prepared at short notice by Pierre (thanks!) to present how the Quantum technologies are being used in the ALICE experiment. The abstract to Mr Hukill's follows. Clustered Storage is a technology that is driven by business and mission applications. The evolution of Clustered Storage solutions starts first at the alignment between End-users needs and Industry trends: * Push-and-Pull between managing for today versus planning for tomorrow * Breaking down the real business problems to the core applications * Commoditization of clients, servers, and target devices * Interchangeability, Interoperability, Remote Access, Centralized control * Oh, and yes, there is a budget and the "real world" to deal with This presentation will talk through these needs and trends, and then ask the question, ...

  17. Epigenetics and brain evolution.

    Science.gov (United States)

    Keverne, Eric B

    2011-04-01

    Fundamental aspects of mammalian brain evolution occurred in the context of viviparity and placentation brought about by the epigenetic regulation of imprinted genes. Since the fetal placenta hormonally primes the maternal brain, two genomes in one individual are transgenerationally co-adapted to ensure maternal care and nurturing. Advanced aspects of neocortical brain evolution has shown very few genetic changes between monkeys and humans. Although these lineages diverged at approximately the same time as the rat and mouse (20 million years ago), synonymous sequence divergence between the rat and mouse is double that when comparing monkey with human sequences. Paradoxically, encephalization of rat and mouse are remarkably similar, while comparison of the human and monkey shows the human cortex to be three times the size of the monkey. This suggests an element of genetic stability between the brains of monkey and man with a greater emphasis on epigenetics providing adaptable variability.

  18. The metaphysics of evolution.

    Science.gov (United States)

    Dupré, John

    2017-10-06

    This paper briefly describes process metaphysics, and argues that it is better suited for describing life than the more standard thing, or substance, metaphysics. It then explores the implications of process metaphysics for conceptualizing evolution. After explaining what it is for an organism to be a process, the paper takes up the Hull/Ghiselin thesis of species as individuals and explores the conditions under which a species or lineage could constitute an individual process. It is argued that only sexual species satisfy these conditions, and that within sexual species the degree of organization varies. This, in turn, has important implications for species' evolvability. One important moral is that evolution will work differently in different biological domains.

  19. Kamikazes and cultural evolution.

    Science.gov (United States)

    Allen-Hermanson, Sean

    2017-02-01

    Is cultural evolution needed to explain altruistic selfsacrifice? Some contend that cultural traits (e.g. beliefs, behaviors, and for some "memes") replicate according to selection processes that have "floated free" from biology. One test case is the example of suicide kamikaze attacks in wartime Japan. Standard biological mechanisms-such as reciprocal altruism and kin selection-might not seem to apply here: The suicide pilots did not act on the expectation that others would reciprocate, and they were supposedly sacrificing themselves for country and emperor, not close relatives. Yet an examination of both the historical record and the demands of evolutionary theory suggest the kamikaze phenomenon does not cry out for explanation in terms of a special non-biological selection process. This weakens the case for cultural evolution, and has interesting implications for our understanding of altruistic self-sacrifice. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Chromosomal Evolution in Chiroptera

    OpenAIRE

    Sotero-Caio, Cibele G.; Baker, Robert J.; Volleth, Marianne

    2017-01-01

    Chiroptera is the second largest order among mammals, with over 1300 species in 21 extant families. The group is extremely diverse in several aspects of its natural history, including dietary strategies, ecology, behavior and morphology. Bat genomes show ample chromosome diversity (from 2n = 14 to 62). As with other mammalian orders, Chiroptera is characterized by clades with low, moderate and extreme chromosomal change. In this article, we will discuss trends of karyotypic evolution within d...

  1. Software evolution and maintenance

    CERN Document Server

    Tripathy, Priyadarshi

    2014-01-01

    Software Evolution and Maintenance: A Practitioner's Approach is an accessible textbook for students and professionals, which collates the advances in software development and provides the most current models and techniques in maintenance.Explains two maintenance standards: IEEE/EIA 1219 and ISO/IEC14764Discusses several commercial reverse and domain engineering toolkitsSlides for instructors are available onlineInformation is based on the IEEE SWEBOK (Software Engineering Body of Knowledge)

  2. Electroweak evolution equations

    International Nuclear Information System (INIS)

    Ciafaloni, Paolo; Comelli, Denis

    2005-01-01

    Enlarging a previous analysis, where only fermions and transverse gauge bosons were taken into account, we write down infrared-collinear evolution equations for the Standard Model of electroweak interactions computing the full set of splitting functions. Due to the presence of double logs which are characteristic of electroweak interactions (Bloch-Nordsieck violation), new infrared singular splitting functions have to be introduced. We also include corrections related to the third generation Yukawa couplings

  3. Embodied artificial evolution

    OpenAIRE

    Eiben, A. E.; Kernbach, S.; Haasdijk, Evert

    2012-01-01

    Evolution is one of the major omnipresent powers in the universe that has been studied for about two centuries. Recent scientific and technical developments make it possible to make the transition from passively understanding to actively using evolutionary processes. Today this is possible in Evolutionary Computing, where human experimenters can design and manipulate all components of evolutionary processes in digital spaces. We argue that in the near future it will be possible to implement a...

  4. Evolution of microbial pathogens.

    OpenAIRE

    Morschhäuser, J; Köhler, G; Ziebuhr, W; Blum-Oehler, G; Dobrindt, U; Hacker, J

    2000-01-01

    Various genetic mechanisms including point mutations, genetic rearrangements and lateral gene transfer processes contribute to the evolution of microbes. Long-term processes leading to the development of new species or subspecies are termed macroevolution, and short-term developments, which occur during days or weeks, are considered as microevolution. Both processes, macro- and microevolution need horizontal gene transfer, which is particularly important for the development of pathogenic micr...

  5. Ontology evolution in physics

    OpenAIRE

    Chan, Michael

    2013-01-01

    With the advent of reasoning problems in dynamic environments, there is an increasing need for automated reasoning systems to automatically adapt to unexpected changes in representations. In particular, the automation of the evolution of their ontologies needs to be enhanced without substantially sacrificing expressivity in the underlying representation. Revision of beliefs is not enough, as adding to or removing from beliefs does not change the underlying formal language. Gene...

  6. On protostellar evolution

    International Nuclear Information System (INIS)

    Westbrook, C.K.; Tarter, C.B.

    1975-01-01

    An investigation of the evolution of spherically symmetric protostars with initial masses in the range 0.1less than or equal toM/M/sub sun/less than or equal to50 has been carried out. In order to perform the calculations, a numerical technique has been developed in which rapid dynamical motions in one region of the star and quasi-static evolution in another region can be simultaneously computed. The general evolutionary features are similar to those found by other workers: an initial free-fall collapse is followed by the creation of a core in hydrostatic equilibrium, and the core's subsequent accretion of the surrounding envelope. However, our final hydrostatic-equilibrium configurations have radii large compared with those of the protostellar models of Larson (but in reasonable agreement with those of conventional pre-main-sequence models). For low-mass protostars (Mless than or equal toM/sub sun/) the luminosity remains relatively small until late evolutionary times and the evolution is very sensitive to the treatment of convective energy transport. For large-mass protostars (Mgreater than or equal to3M/sub sun/) a convective phase never exists, and a fraction (increasing with mass) of the initial mass is ejected by the combined effects of heating and radiation pressure in the envelope

  7. ENVIRONMENT AND PROTOSTELLAR EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yichen [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Tan, Jonathan C., E-mail: yczhang.astro@gmail.com [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)

    2015-04-01

    Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of the resulting star and planetary systems. Here, we study the role of pressure, parameterized via ambient clump mass surface density, on protostellar evolution and appearance, focusing on low-mass Sun-like stars and considering a range of conditions from relatively low pressure filaments in Taurus, to intermediate pressures of cluster-forming clumps like the Orion Nebula Cluster, to very high pressures that may be found in the densest infrared dark clouds or in the Galactic center. We present unified analytic and numerical models for the collapse of prestellar cores, accretion disks, protostellar evolution, and bipolar outflows, coupled with radiative transfer calculations and a simple astrochemical model to predict CO gas-phase abundances. Prestellar cores in high-pressure environments are smaller and denser and thus collapse with higher accretion rates and efficiencies, resulting in higher luminosity protostars with more powerful outflows. The protostellar envelope is heated to warmer temperatures, affecting infrared morphologies (and thus classification) and astrochemical processes like CO depletion onto dust grain ice mantles (and thus CO morphologies). These results have general implications for star and planet formation, especially via their effect on astrochemical and dust grain evolution during infall to and through protostellar accretion disks.

  8. Frost evolution in tailings

    International Nuclear Information System (INIS)

    1991-04-01

    A review was carried out on the physical and thermal mechanisms of permafrost evaluation in soils and uranium tailings. The primary mechanism controlling permafrost evolution is conductive heat transfer with the latent heat of fusion of water being liberated as phase change occurs. Depending on the soil properties and freezing rate, pore water can be expelled from the frost front or pore water can migrate towards the frost front. Solute redistribution may occur as the frost front penetrates into the soil. The rate of frost penetration is a function of the thermal properties of the tailings and the climatic conditions. Computer modelling programmes capable of modelling permafrost evolution were reviewed. The GEOTHERM programme was selected as being the most appropriate for this study. The GEOTHERM programme uses the finite element method of thermal analysis. The ground surface temperature is determined by solving the energy balance equations a the ground surface. The GEOTHERM programme was used to simulate the permafrost evolution in the Key Lake Mine tailings located in north central Saskatchewan. The analyses indicated that the existing frozen zones in the tailing pond will eventually thaw if an average snow depth covers the tailings. Hundreds of years are required to thaw the tailings. If minimal snow cover is present the extent of the frozen zone in the tailings will increase

  9. The evolution of teaching.

    Science.gov (United States)

    Fogarty, L; Strimling, P; Laland, K N

    2011-10-01

    Teaching, alongside imitation, is widely thought to underlie the success of humanity by allowing high-fidelity transmission of information, skills, and technology between individuals, facilitating both cumulative knowledge gain and normative culture. Yet, it remains a mystery why teaching should be widespread in human societies but extremely rare in other animals. We explore the evolution of teaching using simple genetic models in which a single tutor transmits adaptive information to a related pupil at a cost. Teaching is expected to evolve where its costs are outweighed by the inclusive fitness benefits that result from the tutor's relatives being more likely to acquire the valuable information. We find that teaching is not favored where the pupil can easily acquire the information on its own, or through copying others, or for difficult to learn traits, where teachers typically do not possess the information to pass on to relatives. This leads to a narrow range of traits for which teaching would be efficacious, which helps to explain the rarity of teaching in nature, its unusual distribution, and its highly specific nature. Further models that allow for cumulative cultural knowledge gain suggest that teaching evolved in humans because cumulative culture renders otherwise difficult-to-acquire valuable information available to teach. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  10. Consciousness and biological evolution.

    Science.gov (United States)

    Lindahl, B I

    1997-08-21

    It has been suggested that if the preservation and development of consciousness in the biological evolution is a result of natural selection, it is plausible that consciousness not only has been influenced by neural processes, but has had a survival value itself; and it could only have had this, if it had also been efficacious. This argument for mind-brain interaction is examined, both as the argument has been developed by William James and Karl Popper and as it has been discussed by C.D. Broad. The problem of identifying mental phenomena with certain neural phenomena is also addressed. The main conclusion of the analysis is that an explanation of the evolution of consciousness in Darwinian terms of natural selection does not rule out that consciousness may have evolved as a mere causally inert effect of the evolution of the nervous system, or that mental phenomena are identical with certain neural phenomena. However, the interactionistic theory still seems, more plausible and more fruitful for other reasons brought up in the discussion.

  11. Reconstructing human evolution

    CERN Multimedia

    AUTHOR|(CDS)2074069

    1999-01-01

    One can reconstruct human evolution using modern genetic data and models based on the mathematical theory of evolution and its four major factors : mutation, natural selection, statistical fluctuations in finite populations (random genetic drift), and migration. Archaeology gives some help on the major dates and events of the process. Chances of studying ancient DNA are very limited but there have been a few successful results. Studying DNA instead of proteins, as was done until a few years ago, and in particular the DNA of mitochondria and of the Y chromosome which are transmitted, respectively, by the maternal line and the paternal line, has greatly simplified the analysis. It is now possible to carry the analysis on individuals, while earlier studies were of necessity based on populations. Also the evolution of ÒcultureÓ (i.e. what we learn from others), in particular that of languages, gives some help and can be greatly enlightened by genetic studies. Even though it is largely based on mechanisms of mut...

  12. Anmeldelse af Evolution, Literature and Film

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2011-01-01

    Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film......Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film...

  13. Constrained evolution in numerical relativity

    Science.gov (United States)

    Anderson, Matthew William

    The strongest potential source of gravitational radiation for current and future detectors is the merger of binary black holes. Full numerical simulation of such mergers can provide realistic signal predictions and enhance the probability of detection. Numerical simulation of the Einstein equations, however, is fraught with difficulty. Stability even in static test cases of single black holes has proven elusive. Common to unstable simulations is the growth of constraint violations. This work examines the effect of controlling the growth of constraint violations by solving the constraints periodically during a simulation, an approach called constrained evolution. The effects of constrained evolution are contrasted with the results of unconstrained evolution, evolution where the constraints are not solved during the course of a simulation. Two different formulations of the Einstein equations are examined: the standard ADM formulation and the generalized Frittelli-Reula formulation. In most cases constrained evolution vastly improves the stability of a simulation at minimal computational cost when compared with unconstrained evolution. However, in the more demanding test cases examined, constrained evolution fails to produce simulations with long-term stability in spite of producing improvements in simulation lifetime when compared with unconstrained evolution. Constrained evolution is also examined in conjunction with a wide variety of promising numerical techniques, including mesh refinement and overlapping Cartesian and spherical computational grids. Constrained evolution in boosted black hole spacetimes is investigated using overlapping grids. Constrained evolution proves to be central to the host of innovations required in carrying out such intensive simulations.

  14. Evolution of homeobox genes.

    Science.gov (United States)

    Holland, Peter W H

    2013-01-01

    Many homeobox genes encode transcription factors with regulatory roles in animal and plant development. Homeobox genes are found in almost all eukaryotes, and have diversified into 11 gene classes and over 100 gene families in animal evolution, and 10 to 14 gene classes in plants. The largest group in animals is the ANTP class which includes the well-known Hox genes, plus other genes implicated in development including ParaHox (Cdx, Xlox, Gsx), Evx, Dlx, En, NK4, NK3, Msx, and Nanog. Genomic data suggest that the ANTP class diversified by extensive tandem duplication to generate a large array of genes, including an NK gene cluster and a hypothetical ProtoHox gene cluster that duplicated to generate Hox and ParaHox genes. Expression and functional data suggest that NK, Hox, and ParaHox gene clusters acquired distinct roles in patterning the mesoderm, nervous system, and gut. The PRD class is also diverse and includes Pax2/5/8, Pax3/7, Pax4/6, Gsc, Hesx, Otx, Otp, and Pitx genes. PRD genes are not generally arranged in ancient genomic clusters, although the Dux, Obox, and Rhox gene clusters arose in mammalian evolution as did several non-clustered PRD genes. Tandem duplication and genome duplication expanded the number of homeobox genes, possibly contributing to the evolution of developmental complexity, but homeobox gene loss must not be ignored. Evolutionary changes to homeobox gene expression have also been documented, including Hox gene expression patterns shifting in concert with segmental diversification in vertebrates and crustaceans, and deletion of a Pitx1 gene enhancer in pelvic-reduced sticklebacks. WIREs Dev Biol 2013, 2:31-45. doi: 10.1002/wdev.78 For further resources related to this article, please visit the WIREs website. The author declares that he has no conflicts of interest. Copyright © 2012 Wiley Periodicals, Inc.

  15. Evolution of sexual asymmetry

    Directory of Open Access Journals (Sweden)

    Hoekstra Rolf F

    2004-09-01

    Full Text Available Abstract Background The clear dominance of two-gender sex in recent species is a notorious puzzle of evolutionary theory. It has at least two layers: besides the most fundamental and challenging question why sex exists at all, the other part of the problem is equally perplexing but much less studied. Why do most sexual organisms use a binary mating system? Even if sex confers an evolutionary advantage (through whatever genetic mechanism, why does it manifest that advantage in two, and exactly two, genders (or mating types? Why not just one, and why not more than two? Results Assuming that sex carries an inherent fitness advantage over pure clonal multiplication, we attempt to give a feasible solution to the problem of the evolution of dimorphic sexual asymmetry as opposed to monomorphic symmetry by using a spatial (cellular automaton model and its non-spatial (mean-field approximation. Based on a comparison of the spatial model to the mean-field approximation we suggest that spatial population structure must have played a significant role in the evolution of mating types, due to the largely clonal (self-aggregated spatial distribution of gamete types, which is plausible in aquatic habitats for physical reasons, and appears to facilitate the evolution of a binary mating system. Conclusions Under broad ecological and genetic conditions the cellular automaton predicts selective removal from the population of supposedly primitive gametes that are able to mate with their own type, whereas the non-spatial model admits coexistence of the primitive type and the mating types. Thus we offer a basically ecological solution to a theoretical problem that earlier models based on random gamete encounters had failed to resolve.

  16. Evolution before genes

    Directory of Open Access Journals (Sweden)

    Vasas Vera

    2012-01-01

    Full Text Available Abstract Background Our current understanding of evolution is so tightly linked to template-dependent replication of DNA and RNA molecules that the old idea from Oparin of a self-reproducing 'garbage bag' ('coacervate' of chemicals that predated fully-fledged cell-like entities seems to be farfetched to most scientists today. However, this is exactly the kind of scheme we propose for how Darwinian evolution could have occurred prior to template replication. Results We cannot confirm previous claims that autocatalytic sets of organic polymer molecules could undergo evolution in any interesting sense by themselves. While we and others have previously imagined inhibition would result in selectability, we found that it produced multiple attractors in an autocatalytic set that cannot be selected for. Instead, we discovered that if general conditions are satisfied, the accumulation of adaptations in chemical reaction networks can occur. These conditions are the existence of rare reactions producing viable cores (analogous to a genotype, that sustains a molecular periphery (analogous to a phenotype. Conclusions We conclude that only when a chemical reaction network consists of many such viable cores, can it be evolvable. When many cores are enclosed in a compartment there is competition between cores within the same compartment, and when there are many compartments, there is between-compartment competition due to the phenotypic effects of cores and their periphery at the compartment level. Acquisition of cores by rare chemical events, and loss of cores at division, allows macromutation, limited heredity and selectability, thus explaining how a poor man's natural selection could have operated prior to genetic templates. This is the only demonstration to date of a mechanism by which pre-template accumulation of adaptation could occur. Reviewers This article was reviewed by William Martin and Eugene Koonin.

  17. Glucosinolate structures in evolution.

    Science.gov (United States)

    Agerbirk, Niels; Olsen, Carl Erik

    2012-05-01

    By 2000, around 106 natural glucosinolates (GSLs) were probably documented. In the past decade, 26 additional natural GSL structures have been elucidated and documented. Hence, the total number of documented GSLs from nature by 2011 can be estimated to around 132. A considerable number of additional suggested structures are concluded not to be sufficiently documented. In many cases, NMR spectroscopy would have provided the missing structural information. Of the GSLs documented in the past decade, several are of previously unexpected structures and occur at considerable levels. Most originate from just four species: Barbarea vulgaris, Arabidopsis thaliana, Eruca sativa and Isatis tinctoria. Acyl derivatives of known GSLs comprised 15 of the 26 newly documented structures, while the remaining exhibited new substitution patterns or chain length, or contained a mercapto group or related thio-functionality. GSL identification methods are reviewed, and the importance of using authentic references and structure-sensitive detection methods such as MS and NMR is stressed, especially when species with relatively unknown chemistry are analyzed. An example of qualitative GSL analysis is presented with experimental details (group separation and HPLC of both intact and desulfated GSLs, detection and structure determination by UV, MS, NMR and susceptibility to myrosinase) with emphasis on the use of NMR for structure elucidation of even minor GSLs and GSL hydrolysis products. The example includes identification of a novel GSL, (R)-2-hydroxy-2-(3-hydroxyphenyl)ethylglucosinolate. Recent investigations of GSL evolution, based on investigations of species with well established phylogeny, are reviewed. From the relatively few such investigations, it is already clear that GSL profiles are regularly subject to evolution. This result is compatible with natural selection for specific GSL side chains. The probable existence of structure-specific GSL catabolism in intact plants suggests

  18. Gas evolution from spheres

    Science.gov (United States)

    Longhurst, G. R.

    1991-04-01

    Gas evolution from spherical solids or liquids where no convective processes are active is analyzed. Three problem classes are considered: (1) constant concentration boundary, (2) Henry's law (first order) boundary, and (3) Sieverts' law (second order) boundary. General expressions are derived for dimensionless times and transport parameters appropriate to each of the classes considered. However, in the second order case, the non-linearities of the problem require the presence of explicit dimensional variables in the solution. Sample problems are solved to illustrate the method.

  19. Evolution of atherectomy devices.

    Science.gov (United States)

    Al Khoury, G; Chaer, R

    2011-08-01

    Percutaneous atherectomy provides an alternative approach to the endovascular treatment of peripheral atherosclerotic occlusive disease beyond angioplasty and stenting, and has the theoretical advantage of lesion debulking and minimizing barotrauma to the vessel wall. Atherectomy has evolved greatly during the last decade, with currently four FDA approved devices for the treatment of peripheral arterial disease. Several reports have focused on the initial technical success rates, and demonstrated the safety and short as well as mid-term efficacy of atherectomy devices. This article will review the evolution of current atherectomy devices and the associated literature.

  20. Microphysics evolution and methodology

    International Nuclear Information System (INIS)

    Dionisio, J.S.

    1990-01-01

    A few general features of microscopics evolution and their relationship with microscopics methodology are briefly surveyed. Several pluri-disciplinary and interdisciplinary aspects of microscopics research are also discussed in the present scientific context. The need for an equilibrium between individual tendencies and collective constraints required by team work, already formulated thirty years ago by Frederic Joliot, is particularly stressed in the present conjuncture of Nuclear Research favouring very large team projects and discouraging individual initiatives. The increasing importance of the science of science (due to their multiple social, economical, ecological aspects) and the stronger competition between national and international tendencies of scientific (and technical) cooperation are also discussed. (author)

  1. Chemical evolution of galaxies

    International Nuclear Information System (INIS)

    Pagel, B.E.J.

    1990-01-01

    Initial conditions are probably set by results of Big Bang nucleosynthesis (BBNS) without intervening complications affecting the composition of visible matter so that extrapolation of observed abundances to BBNS products seems fairly secure. Primordial helium and deuterium abundances deduced in this way place upper and lower limits on baryonic density implying that both baryonic and non-baryonic dark matter exist and predicting no more than 3 neutrino flavours as recently confirmed in accelerator experiments. The validity of simple galactic chemical evolution models assumed in extrapolating back to the Big Bang is examined in the light of the frequency distribution of iron or oxygen abundances in the Galactic halo, bulge and disk. (orig.)

  2. Electrochemical Hydrogen Evolution

    DEFF Research Database (Denmark)

    Laursen, A.B.; Varela Gasque, Ana Sofia; Dionigi, F.

    2012-01-01

    The electrochemical hydrogen evolution reaction (HER) is growing in significance as society begins to rely more on renewable energy sources such as wind and solar power. Thus, research on designing new, inexpensive, and abundant HER catalysts is important. Here, we describe how a simple experiment...... catalysts based on this. Suited for upper-level high school and first-year university students, this exercise involves using a basic two-cell electrochemical setup to test multiple electrode materials as catalysts at one applied potential, and then constructing a volcano curve with the resulting currents...

  3. Nonlinear evolution equations

    CERN Document Server

    Uraltseva, N N

    1995-01-01

    This collection focuses on nonlinear problems in partial differential equations. Most of the papers are based on lectures presented at the seminar on partial differential equations and mathematical physics at St. Petersburg University. Among the topics explored are the existence and properties of solutions of various classes of nonlinear evolution equations, nonlinear imbedding theorems, bifurcations of solutions, and equations of mathematical physics (Navier-Stokes type equations and the nonlinear Schrödinger equation). The book will be useful to researchers and graduate students working in p

  4. A new evolution equation

    International Nuclear Information System (INIS)

    Laenen, E.

    1995-01-01

    We propose a new evolution equation for the gluon density relevant for the region of small x B . It generalizes the GLR equation and allows deeper penetration in dense parton systems than the GLR equation does. This generalization consists of taking shadowing effects more comprehensively into account by including multigluon correlations, and allowing for an arbitrary initial gluon distribution in a hadron. We solve the new equation for fixed α s . We find that the effects of multigluon correlations on the deep-inelastic structure function are small. (orig.)

  5. Chemical evolution coefficients for the study of galactic evolution

    Energy Technology Data Exchange (ETDEWEB)

    Mallik, D C.V. [Indian Inst. of Astrophysics, Bangalore

    1980-05-01

    A new evaluation of chemical evolution coefficients has been made using recent stellar evolution and nucleosynthesis data. The role of the low and intermediate mass stars in galactic nucleosynthesis has been emphasized. A significant amount of /sup 4/He, /sup 12/C and neutron-rich species is found to be contributed by these stars. Comparison with observed abundances suggests a primary origin of /sup 14/N. The simple model of galactic evolution with the new coefficients has been used to derive the ratio of helium to heavy element enrichment in the Galaxy. The new stellar evolution data do not explain the large value of this ratio that has been determined observationally.

  6. Chemical evolution coefficients for the study of galactic evolution

    International Nuclear Information System (INIS)

    Mallik, D.C.V.

    1980-01-01

    A new evaluation of chemical evolution coefficients has been made using recent stellar evolution and nucleosynthesis data. The role of the low and intermediate mass stars in galactic nuclosynthesis has been emphasized. A significant amount of 4 He, 12 C and neutron-rich species is found to be contributed by these stars. Comparison with observed abundances suggests a primary origin of 14 N. The simple model of galactic evolution with the new coefficients has been used to derive the ratio of helium to heavy element enrichment in the Galaxy. The new stellar evolution data do not explain the large value of this ratio that has been determined observationally. (orig.)

  7. Concrete Chemical Evolution

    Energy Technology Data Exchange (ETDEWEB)

    D.H. Tang

    1998-07-31

    The objectives of this analysis are to discuss and evaluate testing results that were performed for the M&O by the Pennsylvania State University (PSU) to evaluate the potential long-term evolution of organic admixtures in cementitious materials at elevated temperatures. The testing was designed to help provide a basis for a determination by the Performance Assessment group (PA) of the long-term acceptability and longevity of cementitious materials for repository use. The main purpose of the testing was to assess the evolution of gases (especially CO{sub 2}) from hydrated cement paste at elevated temperatures and to determine the impact on alkalinity, i.e., the pH value of cement paste pore solution. This information in turn can be used as scoping information to determine if further tests of this nature are needed to support PA. As part of this discussion and evaluation of the PSU results, an assessment of alkalinity in a ''cementitious repository'' and an evaluation of organic materials are presented.

  8. The Evolution of Photosynthesis

    International Nuclear Information System (INIS)

    Broda, E.

    1976-01-01

    This Review was written by Engelbert Broda, an Austrian Chemist and Physicist, on February the 10th 1976. The merits of the inductive and the deductive approach in tracing the pathways of evolution are discussed. Using the latter approach, it is concluded that photosynthesis followed fermentation as a method of obtaining energy-rich compounds, especially ATP. Photosynthesis probably arose by utilization of membranes for bioenergetic processes. Originally photosynthesis served photophosphorylation (ATP production), later reducing power was also made, either by open-ended, light-powered, electron flow or driven by ATP; ultimate electron donors were at first hydrogen or sulfur compounds, and later water, the last-named capability Was acquired by prokaryotic algae the earliest plants, similar to the recent blue-greens. When free oxygen entered the atmosphere for the first time, various forms of respiration (oxidative phosphorylation) became possible. Mechanistically, respiration evolved from photosynthesis (‘conversion hypotheses’). Prokaryotic algae are probably the ancestors of the chloroplasts in the eukaryotes, In the evolution of the eukaryotes, not much change in the basic processes of photosynthesis occurred.(author)

  9. Concrete Chemical Evolution

    International Nuclear Information System (INIS)

    D.H. Tang

    1998-01-01

    The objectives of this analysis are to discuss and evaluate testing results that were performed for the M andO by the Pennsylvania State University (PSU) to evaluate the potential long-term evolution of organic admixtures in cementitious materials at elevated temperatures. The testing was designed to help provide a basis for a determination by the Performance Assessment group (PA) of the long-term acceptability and longevity of cementitious materials for repository use. The main purpose of the testing was to assess the evolution of gases (especially CO 2 ) from hydrated cement paste at elevated temperatures and to determine the impact on alkalinity, i.e., the pH value of cement paste pore solution. This information in turn can be used as scoping information to determine if further tests of this nature are needed to support PA. As part of this discussion and evaluation of the PSU results, an assessment of alkalinity in a ''cementitious repository'' and an evaluation of organic materials are presented

  10. Evolution of stellar systems

    International Nuclear Information System (INIS)

    Vader, P.

    1981-01-01

    The stellar systems of which the evolution will be considered in this thesis, are either galaxies, which contain about 10 11 stars, or binary systems, which consist of only two stars. It is seen that binary systems can give us some insight into the relative age of the nucleus of M31. The positive correlation between the metal content of a galaxy and its mass, first noted for elliptical galaxies, seems to be a general property of galaxies of all types. The observed increase of metallicity with galaxy mass is too large to be accounted for by differences in the evolutionary stage of galaxies. To explain the observed correlation it is proposed that a relatively larger proportion of massive stars is formed in more massive galaxies. The physical basis is that the formation of massive stars seems to be tied to the enhanced gas-dynamical activity in more massive galaxies. A specific aspect of the production of heavy elements by massive stars is investigated in some detail. In 1979 a cluster of 18 point X-ray sources within 400 pc of the centre of M31 was detected with the Einstein satellite. This is a remarkable result since no equivalent of this cluster has been observed in the nucleus of our own Galaxy, which otherwise is very similar to that of M31. An explanation for this phenomenon is proposed, suggesting that X-ray binaries are the products of the long-term evolution of nova systems. (Auth.)

  11. Evolution of Supernova Remnants

    Science.gov (United States)

    Arbutina, B.

    2017-12-01

    This book, both a monograph and a graduate textbook, is based on my original research and partly on the materials prepared earlier for the 2007 and 2008 IARS Astrophysics Summer School in Istanbul, AstroMundus course 'Supernovae and Their Remnants' that was held for the first time in 2011 at the Department of Astronomy, Faculty of Mathematics, University of Belgrade, and a graduate course 'Evolution of Supernova Remnants' that I teach at the aforementioned university. The first part Supernovae (introduction, thermonuclear supernovae, core-collapse supernovae) provides introductory information and explains the classification and physics of supernova explosions, while the second part Supernova remnants (introduction, shock waves, cosmic rays and particle acceleration, magnetic fields, synchrotron radiation, hydrodynamic and radio evolution of supernova remnants), which is the field I work in, is more detailed in scope i.e. technical/mathematical. Special attention is paid to details of mathematical derivations that often cannot be found in original works or available literature. Therefore, I believe it can be useful to both, graduate students and researchers interested in the field.

  12. Evolution of galaxies

    International Nuclear Information System (INIS)

    Palous, J.

    1987-01-01

    The proceedings contain 87 papers divided into 8 chapters. The chapter Bipolar outflows and star formations contains papers on optical and infrared observations of young bipolar outflow objects and the theory thereof, and on observations of cometary nebulae. The chapter Masers and early stellar evolution discusses molecular masers and star forming regions. The following chapter contains papers on initial mass function and star formation rates in galaxies. The chapter Clusters and star formation contains data on OB associations and open star clusters, their development and observations, CO and H 2 in our galaxy, the four vector model of radio emission and an atlas of the wavelength dependence of ultraviolet extinction in the Galaxy. The most voluminous is the chapter Evolution of galaxies. It contains papers on the theories of the physical and chemodynamic development of galaxies of different types, rotation research and rotation velocities of galaxies and their arms, and on mathematical and laboratory models of morphological development. Chapter seven contains papers dealing with active extragalactic objects, quasars and active galactic nuclei. The last chapter discusses cosmological models, the theory of the inflationary universe, and presents an interpretation of the central void and X-ray background. (M.D.). 299 figs., 48 tabs., 1651 refs

  13. Ultrastructure, macromolecules, and evolution

    CERN Document Server

    Dillon, Lawrence S

    1981-01-01

    Thus far in the history of biology, two, and only two, fundamental principles have come to light that pervade and unify the entire science-the cell theory and the concept of evolution. While it is true that recently opened fields of inves­ tigation have given rise to several generalizations of wide impact, such as the universality of DNA and the energetic dynamics of ecology, closer inspection reveals them to be part and parcel of either of the first two mentioned. Because in the final analysis energy can act upon an organism solely at the cellular level, its effects may be perceived basically to represent one facet of cell me­ tabolism. Similarly, because the DNA theory centers upon the means by which cells build proteins and reproduce themselves, it too proves to be only one more, even though an exciting, aspect of the cell theory. In fact, if the matter is given closer scrutiny, evolution itself can be viewed as being a fundamental portion of the cell concept, for its effects arise only as a consequence ...

  14. Modeling Protein Evolution

    Science.gov (United States)

    Goldstein, Richard; Pollock, David

    The study of biology is fundamentally different from many other scientific pursuits, such as geology or astrophysics. This difference stems from the ubiquitous questions that arise about function and purpose. These are questions concerning why biological objects operate the way they do: what is the function of a polymerase? What is the role of the immune system? No one, aside from the most dedicated anthropist or interventionist theist, would attempt to determine the purpose of the earth's mantle or the function of a binary star. Among the sciences, it is only biology in which the details of what an object does can be said to be part of the reason for its existence. This is because the process of evolution is capable of improving an object to better carry out a function; that is, it adapts an object within the constraints of mechanics and history (i.e., what has come before). Thus, the ultimate basis of these biological questions is the process of evolution; generally, the function of an enzyme, cell type, organ, system, or trait is the thing that it does that contributes to the fitness (i.e., reproductive success) of the organism of which it is a part or characteristic. Our investigations cannot escape the simple fact that all things in biology (including ourselves) are, ultimately, the result of an evolutionary process.

  15. Chemical evolution of galaxies

    International Nuclear Information System (INIS)

    Pagel, B.E.J.

    1979-01-01

    The chemical evolution of disk galaxies is discussed with special reference to results obtained from studies of the oxygen abundance in H II regions. Normal spirals (including our own) display the by now well known radial abundance gradient, which is discussed on the basis of the simple enrichment model and other models. The Magellanic Clouds, on the other hand, and the barred spiral NGC 1365, have been found to have little or no abundance gradient, implying a very different sort of evolution that may involve large-scale mixing. Finally, the simple model is tested against a number of results in H II regions where the ratio of total mass to mass of residual gas can be estimated. It turns out to fit adequately the Magellanic Clouds and a number of H II regions in the outer parts of spiral galaxies, but in more inner parts it fails, as do more sophisticated models involving infall during the formation of galactic disks that have proved very successful in other respects. (Auth.)

  16. Stellar Structure and Evolution

    CERN Document Server

    Kippenhahn, Rudolf; Weiss, Achim

    2013-01-01

    This long-awaited second edition of the classical textbook on Stellar Structure and Evolution by Kippenhahn and Weigert is a thoroughly revised version of the original text. Taking into account modern observational constraints as well as additional physical effects such as mass loss and diffusion, Achim Weiss and Rudolf Kippenhahn have succeeded in bringing the book up to the state-of-the-art with respect to both the presentation of stellar physics and the presentation and interpretation of current sophisticated stellar models. The well-received and proven pedagogical approach of the first edition has been retained. The book provides a comprehensive treatment of the physics of the stellar interior and the underlying fundamental processes and parameters. The models developed to explain the stability, dynamics and evolution of the stars are presented and great care is taken to detail the various stages in a star’s life. Just as the first edition, which remained a standard work for more than 20 years after its...

  17. Student Visual Communication of Evolution

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin

    2017-06-01

    Despite growing recognition of the importance of visual representations to science education, previous research has given attention mostly to verbal modalities of evolution instruction. Visual aspects of classroom learning of evolution are yet to be systematically examined by science educators. The present study attends to this issue by exploring the types of evolutionary imagery deployed by secondary students. Our visual design analysis revealed that students resorted to two larger categories of images when visually communicating evolution: spatial metaphors (images that provided a spatio-temporal account of human evolution as a metaphorical "walk" across time and space) and symbolic representations ("icons of evolution" such as personal portraits of Charles Darwin that simply evoked evolutionary theory rather than metaphorically conveying its conceptual contents). It is argued that students need opportunities to collaboratively critique evolutionary imagery and to extend their visual perception of evolution beyond dominant images.

  18. Evolution across the Curriculum: Microbiology

    Directory of Open Access Journals (Sweden)

    Alita R. Burmeister

    2016-05-01

    Full Text Available An integrated understanding of microbiology and evolutionary biology is essential for students pursuing careers in microbiology and healthcare fields. In this Perspective, we discuss the usefulness of evolutionary concepts and an overall evolutionary framework for students enrolled in microbiology courses. Further, we propose a set of learning goals for students studying microbial evolution concepts. We then describe some barriers to microbial evolution teaching and learning and encourage the continued incorporation of evidence-based teaching practices into microbiology courses at all levels. Next, we review the current status of microbial evolution assessment tools and describe some education resources available for teaching microbial evolution. Successful microbial evolution education will require that evolution be taught across the undergraduate biology curriculum, with a continued focus on applications and applied careers, while aligning with national biology education reform initiatives.

  19. Evolution across the Curriculum: Microbiology

    Science.gov (United States)

    Burmeister, Alita R.; Smith, James J.

    2016-01-01

    An integrated understanding of microbiology and evolutionary biology is essential for students pursuing careers in microbiology and healthcare fields. In this Perspective, we discuss the usefulness of evolutionary concepts and an overall evolutionary framework for students enrolled in microbiology courses. Further, we propose a set of learning goals for students studying microbial evolution concepts. We then describe some barriers to microbial evolution teaching and learning and encourage the continued incorporation of evidence-based teaching practices into microbiology courses at all levels. Next, we review the current status of microbial evolution assessment tools and describe some education resources available for teaching microbial evolution. Successful microbial evolution education will require that evolution be taught across the undergraduate biology curriculum, with a continued focus on applications and applied careers, while aligning with national biology education reform initiatives. Journal of Microbiology & Biology Education PMID:27158306

  20. The evolution of Lean organizations

    OpenAIRE

    Serafinas, Dalius; Ruželė, Darius

    2014-01-01

    Remiantis evoliucijos tyrimų modeliais bei autorių sudarytu evoliucionuojančios organizacijos modeliu,straipsnyje analizuojama Lean vadybos metodologija ir tiriama, kaip evoliucionuoja ją įgyvendinančios Lietuvosgamybinės organizacijos. The purpose of this paper is to examine the evolution of Lean organizations.Design/methodology/approach: a conceptual literature on the evolution of species, organisms and organizations was reviewed and an original model (framework) of the evolution of orga...

  1. Tracing Cultural Evolution Through Memetics

    OpenAIRE

    Tiktik Dewi Sartika

    2004-01-01

    Viewing human being, as a part of evolution process is still a controversial issue for some people, in fact the evolution runs. As a sociocultural entity, human being has distinctive characters in its evolution process. A Theory inherited from Darwin may have only been able to answer how a simple unit such genes evolve to such complex animal like human. Yet, how among those complex animals interact, communicate, and replicate idea in so forth formed a such self-organized sociocultural complex...

  2. Evolution of Vision

    Science.gov (United States)

    Ostrovsky, Mikhail

    The evolution of photoreception, giving rise to eye, offers a kaleidoscopic view on selection acting at both the organ and molecular levels. The molecular level is mainly considered in the lecture. The greatest progress to date has been made in relation to the opsin visual pigments. Opsins appeared before eyes did. Two- and three-dimensional organization for rhodopsin in the rod outer segment disk membrane, as well as molecular mechanisms of visual pigments spectral tuning, photoisomerization and also opsin as a G-protein coupled receptor are considered. Molecular mechanisms of visual pigments spectral tuning, namely switching of chromophore (physiological time scale) and amino acid changes in the chromophore site of opsin (evolutionary time scale) is considered in the lecture. Photoisomerization of rhodopsin chromophore, 11-cis retinal is the only photochemical reaction in vision. The reaction is extemely fast (less that 200 fs) and high efficient (. is 0.65). The rhodopsin photolysis and kinetics of the earlier products appearance, photo- and bathorhodopsin, is considered. It is known that light is not only a carrier of information, but also a risk factor of damage to the eye. This photobiological paradox of vision is mainly due to the nature of rhodopsin chromophore. Photooxidation is the base of the paradox. All factors present in the phototrceptor cells to initiate free-radical photooxidation: photosensitizers, oxygen and substrates of oxidation: lipids and proteins (opsin). That is why photoprotective system of the eye structures appeared in the course of evolution. Three lines of protective system to prevent light damage to the retina and retina pigment epithelium is known: permanent renewal of rod and cone outer segment, powerful antioxidant system and optical media as cut-off filters where the lens is a key component. The molecular mechanisms of light damage to the eye and photoprotective system of the eye is considered in the lecture. The molecular

  3. Micro-droplet based directed evolution outperforms conventional laboratory evolution

    DEFF Research Database (Denmark)

    Sjostrom, Staffan L.; Huang, Mingtao; Nielsen, Jens

    2014-01-01

    We present droplet adaptive laboratory evolution (DrALE), a directed evolution method used to improve industrial enzyme producing microorganisms for e.g. feedstock digestion. DrALE is based linking a desired phenotype to growth rate allowing only desired cells to proliferate. Single cells are con...... a whole-genome mutated library of yeast cells for α-amylase activity....

  4. Evolution of filament barbs.

    Science.gov (United States)

    Liu, R.; Xu, Y.; Wang, H.

    We present a selected few cases in which the sense of chirality of filament barbs changed within periods as short as hours. We investigate in detail a quiescent filament on 2003 September 10 and 11. Of its four barbs displaying such changes, only one overlays a small polarity inversion line inside the EUV filament channel (EFC). No magnetic elements with magnitude above the noise level were detected at the endpoints of all barbs. In particular, a pair of barbs first approached toward, and then departed from, each other in Halpha , with the barb endpoints migrating as far as ˜ 10 arcsec. We conclude that the evolution of the barbs was driven by flux emergence and cancellation of small bipolar units at the EFC border.

  5. ABWR evolution program

    International Nuclear Information System (INIS)

    Omoto, A.; Tanabe, A.; Moriya, K.; Dillmann, C.W.

    1993-01-01

    The ABWR plant is becoming a commercial reality in Japan where the first two units are being built by the Tokyo Electric Power Company. Although these units are scheduled to come on line in 1996 and '97, the Tokyo Electric Power Company, jointly with NSSS vendors (General Electric, Toshiba and Hitachi) and Japanese BWR utilities, initiated a program for a new plant design. This program is aimed at the further evolution of the ABWR to take advantage of new technological developments and to meet possible social changes in the years to come. The expected time for the first-of-a-kind plant to come on line is in the 2010's when the first generation plants in Japan may approach the time for replacement. This paper presents the ouline of this program with focus on the utility requirements and candidate technologies. (orig.)

  6. Evolution of dwarf binaries

    International Nuclear Information System (INIS)

    Tutukov, A.V.; Fedorova, A.V.; Yungel'son, L.R.

    1982-01-01

    The conditions of mass exchange in close binary systems with masses of components less or equal to one solar mass have been analysed for the case, when the system radiates gravitational waves. It has been shown that the mass exchange rate depends in a certain way on the mass ratio of components and on the mass of component that fills its inner critical lobe. The comparison of observed periods, masses of contact components, and mass exchange rates of observed cataclysmic binaries have led to the conclusion that the evolution of close binaries WZ Sge, OY Car, Z Cha, TT Ari, 2A 0311-227, and G 61-29 may be driven by the emission of gravitational waves [ru

  7. Evolution of paradigms

    International Nuclear Information System (INIS)

    Reuss, P.

    1997-01-01

    The evolution of the concepts and methods used for describing neutronics through the last thirty years is reviewed, with the important role attributed to computer technology and the capacity to perform more precise calculations and models; the various codes such as HETAIRE and APOLLO, used for the Boltzmann equation, are discussed, together with the calculation methods and theories that gain interest or those which were more or less discarded depending on the modelling capacities and nuclear industry choices. The role of experimentations is still essential for neutronics, in order to supply data when theory or data are limited or to validate models and codes. Trends are with structured and modular codes integrating all the know-how of a domain and with increased cooperation with other sectors such as thermohydraulics, thermomechanics, etc

  8. Lossless conditional schema evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Böhlen, Michael

    2004-01-01

    is a precondition for a flexible semantics that allows to correctly answer general queries over evolving schemas. The key challenge is to handle attribute mismatches between the intended and recorded schema in a consistent way. We provide a parametric approach to resolve mismatches according to the needs......Conditional schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation changes some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples and the recorded schema of tuples is at the core...... of a DBMS that supports schema evolution. We propose to keep track of schema mismatches at the level of individual tuples, and prove that evolving schemas with conditional schema changes, in contrast to database systems relying on data migration, are lossless when the schema evolves. The lossless property...

  9. Explaining Poverty Evolution

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Mohammad Azhar; Jones, Edward Samuel

    Measuring poverty remains a complex and contentious issue. This is particularly true in sub-Saharan Africa where poverty rates are higher, information bases typically weaker, and the underlying determinants of welfare relatively volatile. This paper employs recently collected data on household...... consumption in Mozambique to examine the evolution of consumption poverty with focus on the period 2002/03 to 2008/09. The paper contributes in four areas. First, the period in question was characterized by major movements in international commodity prices. Mozambique provides an illuminating case study...... of the implications of these world commodity price changes for living standards of poor people. Second, a novel ‘backcasting’ approach using a computable general equilibrium model of Mozambique, linked to a poverty module is introduced. Third, the backcasting approach is also employed to rigorously examine...

  10. Spectral evolution of galaxies

    International Nuclear Information System (INIS)

    Rocca-Volmerange, B.

    1989-01-01

    A recent striking event in Observational Cosmology is the discovery of a large population of galaxies at extreme cosmological distances (extended from spectral redshifts ≅ 1 to ≥ 3) corresponding to a lookback time of 80% of the Universe's age. However when galaxies are observed at such remote epochs, their appearances are affected by at least two simultaneous effects which are respectively a cosmological effect and the intrinsic evolution of their stellar populations which appear younger than in our nearby galaxies. The fundamental problem is first to disentangle the respective contributions of these two effects to apparent magnitudes and colors of distant galaxies. Other effects which are likely to modify the appearance of galaxies are amplification by gravitational lensing and interaction with environment will also be considered. (author)

  11. Manufacturing network evolution

    DEFF Research Database (Denmark)

    Yang, Cheng; Farooq, Sami; Johansen, John

    2011-01-01

    Purpose – This paper examines the effect of changes at the manufacturing plant level on other plants in the manufacturing network and also investigates the role of manufacturing plants on the evolution of a manufacturing network. Design/methodology/approach –The research questions are developed...... different manufacturing plants in the network and their impact on network transformation. Findings – The paper highlights the dominant role of manufacturing plants in the continuously changing shape of a manufacturing network. The paper demonstrates that a product or process change at one manufacturing...... by identifying the gaps in the reviewed literature. The paper is based on three case studies undertaken in Danish manufacturing companies to explore in detail their manufacturing plants and networks. The cases provide a sound basis for developing the research questions and explaining the interaction between...

  12. Monitoring Evolution at CERN

    CERN Document Server

    Andrade, P; Murphy, S; Pigueiras, L; Santos, M

    2015-01-01

    Over the past two years, the operation of the CERN Data Centres went through significant changes with the introduction of new mechanisms for hardware procurement, new services for cloud provisioning and configuration management, among other improvements. These changes resulted in an increase of resources being operated in a more dynamic environment. Today, the CERN Data Centres provide over 11000 multi-core processor servers, 130 PB disk servers, 100 PB tape robots, and 150 high performance tape drives. To cope with these developments, an evolution of the data centre monitoring tools was also required. This modernisation was based on a number of guiding rules: sustain the increase of resources, adapt to the new dynamic nature of the data centres, make monitoring data easier to share, give more flexibility to Service Managers on how they publish and consume monitoring metrics and logs, establish a common repository of monitoring data, optimise the handling of monitoring notifications, and replace the previous ...

  13. Evolution of Flat Roofs

    Directory of Open Access Journals (Sweden)

    Şt. Vasiliu

    2009-01-01

    Full Text Available Roofs are constructive subassembles that are located at the top of buildings, which toghether with perimetral walls and some elements of the infrastructure belongs to the subsystem elements that close the building. Roofs must meet resistance requirements to mechanical action, thermal insulating, waterproofing and acoustic, fire resistance, durability, economy and aesthetics. The man saw the need to build roofs from the oldest ancient times. Even if the design of buildings has an empirical character, are known and are preserved until today constructions that are made in antiquity, by the Egyptians, Greeks and Romans with architectural achievements, worthy of admiration and in present time. General composition of civil construction has been influenced throughout the evolution of construction history by the level of production forces and properties of building materials available in every historical epoch. For over five millennia, building materials were stone, wood and ceramic products (concrete was used by theRomans only as filling material.

  14. Allergy in evolution.

    Science.gov (United States)

    Platts-Mills, Thomas A E

    2012-01-01

    The 'foreignness' of proteins that we encounter in our homes and outdoors is in large part dependent on their evolutionary distance from man. This is relevant to understanding the differences between mammalian allergens, e.g. cats, and arthropod allergens, e.g. mites and cockroaches, as well as to understanding responses to a wide range of food allergens. On the other hand, allergic disease has gone through a major evolution of its own from a prehygiene state where there is minimal production of allergen-specific IgE, to the production of high-titer IgE, and then to the dramatic increase in asthma. The challenge is to understand how changes in both hygiene and lifestyle have contributed to the changes in allergic disease. Copyright © 2012 S. Karger AG, Basel.

  15. Raptors and primate evolution.

    Science.gov (United States)

    McGraw, W Scott; Berger, Lee R

    2013-01-01

    Most scholars agree that avoiding predators is a central concern of lemurs, monkeys, and apes. However, given uncertainties about the frequency with which primates actually become prey, the selective importance of predation in primate evolution continues to be debated. Some argue that primates are often killed by predators, while others maintain that such events are relatively rare. Some authors have contended that predation's influence on primate sociality has been trivial; others counter that predation need not occur often to be a powerful selective force. Given the challenges of documenting events that can be ephemeral and irregular, we are unlikely ever to amass the volume of systematic, comparative data we have on such topics as feeding, social dynamics, or locomotor behavior. Nevertheless, a steady accumulation of field observations, insight gained from natural experiments, and novel taphonomic analyses have enhanced understanding of how primates interact with several predators, especially raptors, the subject of this review. Copyright © 2013 Wiley Periodicals, Inc.

  16. The evolution of 'bricolage'.

    Science.gov (United States)

    Duboule, D; Wilkins, A S

    1998-02-01

    The past ten years of developmental genetics have revealed that most of our genes are shared by other species throughout the animal kingdom. Consequently, animal diversity might largely rely on the differential use of the same components, either at the individual level through divergent functional recruitment, or at a more integrated level, through their participation in various genetic networks. Here, we argue that this inevitably leads to an increase in the interdependency between functions that, in turn, influences the degree to which novel variations can be tolerated. In this 'transitionist' scheme, evolution is neither inherently gradualist nor punctuated but, instead, progresses from one extreme to the other, together with the increased complexity of organisms.

  17. Evolution of variable stars

    International Nuclear Information System (INIS)

    Becker, S.A.

    1986-08-01

    Throughout the domain of the H R diagram lie groupings of stars whose luminosity varies with time. These variable stars can be classified based on their observed properties into distinct types such as β Cephei stars, δ Cephei stars, and Miras, as well as many other categories. The underlying mechanism for the variability is generally felt to be due to four different causes: geometric effects, rotation, eruptive processes, and pulsation. In this review the focus will be on pulsation variables and how the theory of stellar evolution can be used to explain how the various regions of variability on the H R diagram are populated. To this end a generalized discussion of the evolutionary behavior of a massive star, an intermediate mass star, and a low mass star will be presented. 19 refs., 1 fig., 1 tab

  18. Student Visual Communication of Evolution

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin

    2017-01-01

    Despite growing recognition of the importance of visual representations to science education, previous research has given attention mostly to verbal modalities of evolution instruction. Visual aspects of classroom learning of evolution are yet to be systematically examined by science educators. The present study attends to this issue by exploring…

  19. Evolution of the TOR Pathway.

    NARCIS (Netherlands)

    Dam, T.J.P. van; Zwartkruis, F.J.; Bos, J.L.; Snel, B.

    2011-01-01

    The TOR kinase is a major regulator of growth in eukaryotes. Many components of the TOR pathway are implicated in cancer and metabolic diseases in humans. Analysis of the evolution of TOR and its pathway may provide fundamental insight into the evolution of growth regulation in eukaryotes and

  20. Mammal Evolution, an mustrated Guide

    African Journals Online (AJOL)

    Mammal Evolution, an mustrated Guide. R.J.G. Savage and M.R. Long. British Museum of Natural ... structural anatomy of fossils can be related to their probable function. The body of the text discusses the ... gnawers, rooters and browsers, mammals on island continents, hoofed herbivores and ftnally primate evolution,.

  1. Nonlinear evolution of MHD instabilities

    International Nuclear Information System (INIS)

    Bateman, G.; Hicks, H.R.; Wooten, J.W.; Dory, R.A.

    1975-01-01

    A 3-D nonlinear MHD computer code was used to study the time evolution of internal instabilities. Velocity vortex cells are observed to persist into the nonlinear evolution. Pressure and density profiles convect around these cells for a weak localized instability, or convect into the wall for a strong instability. (U.S.)

  2. Evolution of the Insects

    Science.gov (United States)

    Grimaldi, David; Engel, Michael S.

    2005-05-01

    This book chronicles the complete evolutionary history of insects--their living diversity and relationships as well as 400 million years of fossils. Introductory sections cover the living species diversity of insects, methods of reconstructing evolutionary relationships, basic insect structure, and the diverse modes of insect fossilization and major fossil deposits. Major sections then explore the relationships and evolution of each order of hexapods. The volume also chronicles major episodes in the evolutionary history of insects from their modest beginnings in the Devonian and the origin of wings hundreds of millions of years before pterosaurs and birds to the impact of mass extinctions and the explosive radiation of angiosperms on insects, and how they evolved into the most complex societies in nature. Whereas other volumes focus on either living species or fossils, this is the first comprehensive synthesis of all aspects of insect evolution. Illustrated with 955 photo- and electron- micrographs, drawings, diagrams, and field photos, many in full color and virtually all of them original, this reference will appeal to anyone engaged with insect diversity--professional entomologists and students, insect and fossil collectors, and naturalists. David Grimaldi and Michael S. Engel have collectively published over 200 scientific articles and monographs on the relationships and fossil record of insects, including 10 articles in the journals Science, Nature, and Proceedings of the National Academy of Sciences. David Grimaldi is curator in the Division of Invertebrate Zoology, American Museum of Natural History and adjunct professor at Cornell University, Columbia University, and the City University of New York. David Grimaldi has traveled in 40 countries on 6 continents, collecting and studying recent species of insects and conducting fossil excavations. He is the author of Amber: Window to the Past (Abrams, 2003). Michael S. Engel is an assistant professor in the

  3. Lakes, Lagerstaetten, and Evolution

    Science.gov (United States)

    Kordesch, E. G.; Park, L. E.

    2001-12-01

    nonmarine organisms, and thus the evolution of freshwater organisms, can occur in a short geologic timespan. Because of their unique and varied conditions, the evolution of nonmarine organisms may be linked to lake basin type as well as lake longevity.

  4. Chess Evolution Visualization.

    Science.gov (United States)

    Lu, Wei-Li; Wang, Yu-Shuen; Lin, Wen-Chieh

    2014-05-01

    We present a chess visualization to convey the changes in a game over successive generations. It contains a score chart, an evolution graph and a chess board, such that users can understand a game from global to local viewpoints. Unlike current graphical chess tools, which focus only on highlighting pieces that are under attack and require sequential investigation, our visualization shows potential outcomes after a piece is moved and indicates how much tactical advantage the player can have over the opponent. Users can first glance at the score chart to roughly obtain the growth and decline of advantages from both sides, and then examine the position relations and the piece placements, to know how the pieces are controlled and how the strategy works. To achieve this visualization, we compute the decision tree using artificial intelligence to analyze a game, in which each node represents a chess position and each edge connects two positions that are one-move different. We then merge nodes representing the same chess position, and shorten branches where nodes on them contain only two neighbors, in order to achieve readability. During the graph rendering, the nodes containing events such as draws, effective checks and checkmates, are highlighted because they show how a game is ended. As a result, our visualization helps players understand a chess game so that they can efficiently learn strategies and tactics. The presented results, evaluations, and the conducted user studies demonstrate the feasibility of our visualization design.

  5. Evolution of reticular pseudodrusen.

    Science.gov (United States)

    Sarks, John; Arnold, Jennifer; Ho, I-Van; Sarks, Shirley; Killingsworth, Murray

    2011-07-01

    To report observations relating to the clinical recognition and possible basis of reticular pseudodrusen (RPD). This retrospective study reports the evolution of RPD in 166 patients who had follow-up of over 1 year using multiple imaging techniques. Mean age when first seen was 73.3 years and the mean period of observation was 4.9 years (range 1-18 years). Associated macular changes were recorded. RPD were first identified in the upper fundus as a reticular network, which then became less obvious, developing a diffuse yellowish appearance. RPD also faded around choroidal neovascularisation (CNV). RPD therefore could be transient but the pattern often remained visible outside the macula or nasal to the discs. Manifestations of age-related macular degeneration (AMD) were present in nearly all eyes and there was a particularly high association with CNV (52.1%). In one clinicopathological case abnormal material was found in the subretinal space. The prevalence of RPD may be underestimated because their recognition depends upon the imaging method used, the area of fundus examined and the confusion with typical drusen. The pathology of one eye suggests that RPD may correspond to material in the subretinal space.

  6. Evolution of Replication Machines

    Science.gov (United States)

    Yao, Nina Y.; O'Donnell, Mike E.

    2016-01-01

    The machines that decode and regulate genetic information require the translation, transcription and replication pathways essential to all living cells. Thus, it might be expected that all cells share the same basic machinery for these pathways that were inherited from the primordial ancestor cell from which they evolved. A clear example of this is found in the translation machinery that converts RNA sequence to protein. The translation process requires numerous structural and catalytic RNAs and proteins, the central factors of which are homologous in all three domains of life, bacteria, archaea and eukarya. Likewise, the central actor in transcription, RNA polymerase, shows homology among the catalytic subunits in bacteria, archaea and eukarya. In contrast, while some “gears” of the genome replication machinery are homologous in all domains of life, most components of the replication machine appear to be unrelated between bacteria and those of archaea and eukarya. This review will compare and contrast the central proteins of the “replisome” machines that duplicate DNA in bacteria, archaea and eukarya, with an eye to understanding the issues surrounding the evolution of the DNA replication apparatus. PMID:27160337

  7. Thioredoxin and evolution

    Science.gov (United States)

    Buchanan, B. B.

    1991-01-01

    Comparisons of primary structure have revealed significant homology between the m type thioredoxins of chloroplasts and the thioredoxins from a variety of bacteria. Chloroplast thioredoxin f, by comparison, remains an enigma: certain residues are invariant with those of the other thioredoxins, but a phylogenetic relationship to bacterial or m thioredoxins seems distant. Knowledge of the evolutionary history of thioredoxin f is, nevertheless, of interest because of its role in photosynthesis. Therefore, we have attempted to gain information on the evolutionary history of chloroplast thioredoxin f, as well as m. Our goal was first to establish the utility of thioredoxin as a phylogenetic marker, and, if found suitable, to deduce the evolutionary histories of the chloroplast thioredoxins. To this end, we have constructed phylogenetic (minimal replacement) trees using computer analysis. The results show that the thioredoxins of bacteria and animals fall into distinct phylogenetic groups - the bacterial group resembling that derived from earlier 16s RNA analysis and the animal group showing a cluster consistent with known relationships. The chloroplast thioredoxins show a novel type of phylogenetic arrangement: one m type aligns with its counterpart of eukaryotic algae, cyanobacteria and other bacteria, whereas the second type (f type) tracks with animal thioredoxin. The results give new insight into the evolution of photosynthesis.

  8. Freud and evolution.

    Science.gov (United States)

    Scharbert, Gerhard

    2009-01-01

    The essay analyzes the influence of evolutionary thought in the work of Sigmund Freud. Based on Freud's initial occupation as a neuro-anatomist and physiologist certain aspects stemming from the history of nature and developmental biological reasoning that played a role in his endeavours to find a new basis for medical psychology will be pointed out. These considerations are to be regarded as prolegomena of the task to reread Freud once again, and in doing so avoiding the verdict that holds his neuro-anatomic and comparative-morphological works as simply "pre-analytic." In fact, the time seems ripe to reconsider in a new context particularly those evolutionary, medical, and cultural-scientific elements in Freud's work that appear inconsistent at first sight. The substantial thesis is that Freud, given the fact that he was trained in comparative anatomy and physiology in the tradition of Johannes Müller, had the capability of synthesizing elements of this new point of view with the findings and interrogations concerning developmental history and the theory of evolution. More over, this was perceived not merely metaphoric, as he himself stressed it (Freud 1999, XIII, 99), but in the sense of Ubertragung, that inscribed terms and methods deriving from the given field into the realm of psychology. The moving force behind this particular Ubertragung came from a dynamically-neurological perception of the soul that emerged in France since 1800, which Freud came to know trough the late work of Charcot.

  9. Evolution, reproduction and autopoiesis

    Directory of Open Access Journals (Sweden)

    Francois Durand

    2017-11-01

    Full Text Available The term autopoiesis was coined to describe the regenerating and self-maintaining chemical systems of cells. The term has subsequently been applied to many different fields, including sociology, systems theory and information systems. This theory postulates that an autopoietic unity (cell, machine is an organised network of processes that exists in a delimited space, which produces components which in turn continuously regenerate and create the network of processes that produced them. The Santiago Theory of Cognition grew from the Theory of Allopoiesis stating that all living systems are cognitive systems, and the process of living is a process of cognition. Cognition is the ability to adapt to a certain environment and cognition emerges because of a continuous bilateral interaction between the system and its environment. The resultant complexity seen in living systems is caused by this interaction between the system and its environment. Autopoiesis and cognition are however opposing concepts because cognition can only exist when the system is open and not closed as autopoiesis suggests. It is also difficult to see how autopoietic systems could originate if they are closed and how the continuous change which we see in evolution can be explained if life consists of autopoietic systems. It is postulated that cells and organisms are in fact open systems relating genetically to ancestors before them and their ever-changing descendants after them and the flow of molecules and energy through an ever-changing ecology.

  10. SRP reactor safety evolution

    International Nuclear Information System (INIS)

    Rankin, D.B.

    1984-01-01

    The Savannah River Plant reactors have operated for over 100 reactor years without an incident of significant consequence to on or off-site personnel. The reactor safety posture incorporates a conservative, failure-tolerant design; extensive administrative controls carried out through detailed operating and emergency written procedures; and multiple engineered safety systems backed by comprehensive safety analyses, adapting through the years as operating experience, changes in reactor operational modes, equipment modernization, and experience in the nuclear power industry suggested. Independent technical reviews and audits as well as a strong organizational structure also contribute to the defense-in-depth safety posture. A complete review of safety history would discuss all of the above contributors and the interplay of roles. This report, however, is limited to evolution of the engineered safety features and some of the supporting analyses. The discussion of safety history is divided into finite periods of operating history for preservation of historical perspective and ease of understanding by the reader. Programs in progress are also included. The accident at Three Mile Island was assessed for its safety implications to SRP operation. Resulting recommendations and their current status are discussed separately at the end of the report. 16 refs., 3 figs

  11. Schramm–Loewner evolution

    CERN Document Server

    Kemppainen, Antti

    2017-01-01

    This book is a short, but complete, introduction to the Loewner equation and the SLEs, which are a family of random fractal curves, as well as the relevant background in probability and complex analysis. The connection to statistical physics is also developed in the text in an example case. The book is based on a course (with the same title) lectured by the author. First three chapters are devoted to the background material, but at the same time, give the reader a good understanding on the overview on the subject and on some aspects of conformal invariance. The chapter on the Loewner equation develops in detail the connection of growing hulls and the differential equation satisfied by families of conformal maps. The Schramm–Loewner evolutions are defined and their basic properties are studied in the following chapter, and the regularity properties of random curves as well as scaling limits of discrete random curves are investigated in the final chapter. The book is aimed at graduate students or researcher...

  12. Sponsorship in evolution.

    Science.gov (United States)

    Grant, M K

    1990-09-01

    Sponsorship appears to be evolving from an original model in which the sponsoring religious institute related to its facilities in a manner resembling a family business, to a model of sponsorship akin to a franchise, to a ministerial partnership. Factors leading to this evolution include tremendous changes within the religious institute itself, including decreases in the number of members and financial stability. Changes within healthcare itself--such as greater competition and declining revenues-have forced hospitals to diversify. One result of these developments has been a radical change in the "rules" of the game. Historically independent entities--hospitals, sponsors, physicians--now have to value interdependence and mutuality. In the family-run model the family (sponsor) had special privileges, as though they "owned" the business. When the number of family members dropped below that necessary to govern, administer, and staff the institute's facilities, they began to move away from the family model to the franchise model, which has more open communication, greater input to decision making by non-family members, and a shift in the family's attention from actual operations to oversight and accountability. Eventually, the franchise model began to give way to the ministerial partnership, characterized by mutuality. Both family and others have roles not only in carrying out the mission, but in actually shaping and forming it.

  13. Tectonic evolution of Mars

    International Nuclear Information System (INIS)

    Wise, D.U.; Golombek, M.P.; McGill, G.E.

    1979-01-01

    Any model for the tectonic evolution of Mars must account for two major crustal elements: the Tharsis bulge and the topographically low and lightly crated northern third of the planet. Ages determined by crater density indicate that both of these elements came into existence very early in Martian history, a conclusion that holds no matter which of the current crater density versus age curves is used. The size of these two major crustal elements and their sequential development suggest that both may be related to a global-scale internal process. It is proposed that the resurfacing of the northern third of Mars is related to subcrustal erosion and isostatic foundering during the life of a first-order convection cell. With the demise of the cell, denser segregations of metallic materials began to coalesce as a gravitatively unstable layer which finally overturned to form the core. In the overturn, lighter crustal materials was shifted laterally and underplated beneath Tharsis to cause rapid and permanent isostatic rise. This was followed by a long-lived thermal phase produced by the hot underplate and by the gravitative energy of core formation slowly making its way to the surface to produce the Tharsis volcanics

  14. The evolution of programs

    CERN Document Server

    Dershowitz, Nachum

    1983-01-01

    -Ecclesiastes 12:12 Programs are invariably subjected to many rorms or transrormation. After an initial version of a program has been designed and developed, it undergoes debugging and certification. In addition, most long-lived pro­ grams have a liCe-cycle that includes modifications to meet amended specifications and extensions for expanded capabilities. Such evolution­ ary aspects of programming are the topic of this monograph. We present rormal methods for manipulating programs and illustrate their applica­ tion with numerous examples. Such methods could be incorporated in semi-automated programming environments, where they would serve to ease the burden on the programmer. We begin by describing a method whereby a given program that achieves one goal can be modified to achieve a different goal or a pro­ gram that computes wrong results can be debugged to achieve the 2 Preface intended results. The abstraction of a set of cognate programs to obtain a program schema, and the instantiation of abstract sc...

  15. Universal pacemaker of genome evolution.

    Science.gov (United States)

    Snir, Sagi; Wolf, Yuri I; Koonin, Eugene V

    2012-01-01

    A fundamental observation of comparative genomics is that the distribution of evolution rates across the complete sets of orthologous genes in pairs of related genomes remains virtually unchanged throughout the evolution of life, from bacteria to mammals. The most straightforward explanation for the conservation of this distribution appears to be that the relative evolution rates of all genes remain nearly constant, or in other words, that evolutionary rates of different genes are strongly correlated within each evolving genome. This correlation could be explained by a model that we denoted Universal PaceMaker (UPM) of genome evolution. The UPM model posits that the rate of evolution changes synchronously across genome-wide sets of genes in all evolving lineages. Alternatively, however, the correlation between the evolutionary rates of genes could be a simple consequence of molecular clock (MC). We sought to differentiate between the MC and UPM models by fitting thousands of phylogenetic trees for bacterial and archaeal genes to supertrees that reflect the dominant trend of vertical descent in the evolution of archaea and bacteria and that were constrained according to the two models. The goodness of fit for the UPM model was better than the fit for the MC model, with overwhelming statistical significance, although similarly to the MC, the UPM is strongly overdispersed. Thus, the results of this analysis reveal a universal, genome-wide pacemaker of evolution that could have been in operation throughout the history of life.

  16. Landscape Evolution Modelling-LAPSUS

    Energy Technology Data Exchange (ETDEWEB)

    Baartman, J. E. M.; Temme, A. J. A. M.; Schoorl, J. M.; Claessens, L.; Viveen, W.; Gorp, W. van; Veldkamp, A.

    2009-07-01

    Landscape evolution modelling can make the consequences of landscape evolution hypotheses explicit and theoretically allows for their falsification and improvement. ideally, landscape evolution models (LEMs) combine the results of all relevant landscape forming processes into an ever-adapting digital landscape (e.g. DEM). These processes may act on different spatial and temporal scales. LAPSUS is such a LEM. Processes that have in different studies been included in LAPSUS are water erosion and deposition, landslide activity, creep, solidification, weathering, tectonics and tillage. Process descriptions are as simple and generic as possible, ensuring wide applicability. (Author) 25 refs.

  17. Landscape Evolution Modelling-LAPSUS

    International Nuclear Information System (INIS)

    Baartman, J. E. M.; Temme, A. J. A. M.; Schoorl, J. M.; Claessens, L.; Viveen, W.; Gorp, W. van; Veldkamp, A.

    2009-01-01

    Landscape evolution modelling can make the consequences of landscape evolution hypotheses explicit and theoretically allows for their falsification and improvement. ideally, landscape evolution models (LEMs) combine the results of all relevant landscape forming processes into an ever-adapting digital landscape (e.g. DEM). These processes may act on different spatial and temporal scales. LAPSUS is such a LEM. Processes that have in different studies been included in LAPSUS are water erosion and deposition, landslide activity, creep, solidification, weathering, tectonics and tillage. Process descriptions are as simple and generic as possible, ensuring wide applicability. (Author) 25 refs.

  18. The chemical evolution of galaxies

    International Nuclear Information System (INIS)

    Chiosi, Cesare

    1986-01-01

    The chemical evolution of galaxies is reviewed with particular attention to the theoretical interpretation of the distribution and abundances of elements in stars and the interstellar medium. The paper was presented to the conference on ''The early universe and its evolution'', Erice, Italy, 1986. The metallicity distribution of the solar vicinity, age metallicity relationship, abundance gradients in the galaxy, external galaxies, star formation and evolution, major sites of nucleosynthesis, yields of chemical elements, chemical models, and the galactic disk, are all discussed. (U.K.)

  19. Experimental evolution in budding yeast

    Science.gov (United States)

    Murray, Andrew

    2012-02-01

    I will discuss our progress in analyzing evolution in the budding yeast, Saccharomyces cerevisiae. We take two basic approaches. The first is to try and examine quantitative aspects of evolution, for example by determining how the rate of evolution depends on the mutation rate and the population size or asking whether the rate of mutation is uniform throughout the genome. The second is to try to evolve qualitatively novel, cell biologically interesting phenotypes and track the mutations that are responsible for the phenotype. Our efforts include trying to alter cell morphology, evolve multicellularity, and produce a biological oscillator.

  20. Evolution of rhinology.

    Science.gov (United States)

    Kaluskar, S K

    2008-06-01

    The study of the nose is as old as civilisation. Various conditions affecting its structure and function has been documented in Edwin Smith Papyrus in hieroglyphic script, an Egyptian writing system of the mid -4th Millennium BC.The major contribution for the complete reconstruction of the nose originated in India by Sushruta in around 600 BC. Writing in Sanskrit in the form of verses he described in detail the technique of total reconstruction, which is still being practiced today as Indian Rhinoplasty. This surgical reconstruction paved the way to modern plastic surgery in Europe and United States in 18th century. Sushruta contributed not only to the plastic surgery of the nose, but described entire philosophy of Head and Neck and other surgery as well. Other notable contributors were Greek physicians, Hippocrate and Galen, and at the birth of the Christianity, Celsus wrote eight books of medical encyclopaedia, which described various conditions affecting nose.Septal and Sinus surgery, in comparison to rhinoplasty did not develop until 17th century. Septal surgery began with total septectomy, sub mucous resection by Killian & Freer in early 20th century and later septoplasty by Cottle in middle of 20th century.Sinus surgery probably originated in Egypt, where instruments were used to remove brain through the ethmoid sinuses as part of the mummification process. In 18th century, empyema of the maxillary sinus was drained through the tooth socket or anterior wall of the sinus, which lead to the evolution of radical procedures of removal of mucous membrane and inferior meatal antrostomy. In the late 20th century, improved understanding of the mucociliary mechanism described by Prof. Messerklinger and Nasal Endoscopy described by Prof. Draf with the development of fibre optics and CT imaging, heralded a new era, which evolved in functional endoscopic sinus surgery. New technology further enhanced the scope of endoscope being used "around and beyond" the nose.

  1. Mechanisms of oxygen evolution

    Energy Technology Data Exchange (ETDEWEB)

    Radmer, R; Cheniae, G

    1976-08-01

    The production of O/sub 2/ from water requires the collaboration of four oxidizing equivalents. When dark-adapted O/sub 2/ evolving photosynthetic material is illuminated by a sequence of short (less than 2 ..mu..sec) saturating flashes, the amount of O/sub 2/ evolved per flash oscillates with a period of four. This indicates that a charge-collector, operating with its own reaction center, successively collects and stores four oxidizing equivalents, which are used in a concerted oxidation of two water molecules. Luminescence, fluorescence, and pH changes also reflect this cycle of four. The O/sub 2/ precursor states are quite stable; under some conditions they can have a lifetime of several minutes. The O/sub 2/-yielding reactions and reactions associated with trap recovery are fast relative to the rate-limiting step of photosynthesis. The molecular identity of the charge-collector is unknown, but correlative evidence suggests that a manganese containing catalyst (approximately 4 Mn/charge collector) participates, possibly directly. Formation of the active Mn-containing catalyst occurs via a multi-quantum process occurring within the System II reaction center. The photoactivated catalyst, located on the inner face of the thylakoid membrane, remains permanently active and essentially inaccessible to chemicals other than analogs of H/sub 2/O (e.g., NH/sub 3/, NH/sub 2/OH). This O/sub 2/ evolving catalyst can be deactivated by a variety of treatments that do not alter the system II reaction center. Anions such as chloride seem to participate rather directly in the O/sub 2/ evolution process via unknown mechanism(s).

  2. The evolution of alliance capabilities

    NARCIS (Netherlands)

    Heimeriks, K.H.; Duysters, G.M.; Vanhaverbeke, W.P.M.

    2004-01-01

    This paper assesses the effectiveness and differential performance effects of learning mechanisms on the evolution of alliance capabilities. Relying on the concept of capability lifecycles, prior research has suggested that different capability levels could be identified in which different

  3. Linguistics: evolution and language change.

    Science.gov (United States)

    Bowern, Claire

    2015-01-05

    Linguists have long identified sound changes that occur in parallel. Now novel research shows how Bayesian modeling can capture complex concerted changes, revealing how evolution of sounds proceeds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Giant lobelias exemplify convergent evolution

    Directory of Open Access Journals (Sweden)

    Givnish Thomas J

    2010-01-01

    Full Text Available Abstract Giant lobeliads on tropical mountains in East Africa and Hawaii have highly unusual, giant-rosette growth forms that appear to be convergent on each other and on those of several independently evolved groups of Asteraceae and other families. A recent phylogenetic analysis by Antonelli, based on sequencing the widest selection of lobeliads to date, raises doubts about this paradigmatic example of convergent evolution. Here I address the kinds of evidence needed to test for convergent evolution and argue that the analysis by Antonelli fails on four points. Antonelli's analysis makes several important contributions to our understanding of lobeliad evolution and geographic spread, but his claim regarding convergence appears to be invalid. Giant lobeliads in Hawaii and Africa represent paradigmatic examples of convergent evolution.

  5. Evolution, Fruit Flies and Gerontology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 11. Evolution, Fruit Flies and Gerontology Evolutionary Biology Helps Unravel the Mysteries of Ageing. Amitabh Joshi. General Article Volume 1 Issue 11 November 1996 pp 51-63 ...

  6. Evolution of ageing since Darwin

    Indian Academy of Sciences (India)

    2008-12-23

    Dec 23, 2008 ... causes of senescence in terms of evolution by natural selec- tion. He rejected the historical ... ism's longevity was somehow determined by its physiolog- ..... Gavrilov L. A. and Gavrilova N. S. 1991 The biology of life span: a.

  7. Towards an alternative evolution model.

    Science.gov (United States)

    van Waesberghe, H

    1982-01-01

    Lamarck and Darwin agreed on the inconstancy of species and on the exclusive gradualism of evolution (nature does not jump). Darwinism, revived as neo-Darwinism, was almost generally accepted from about 1930 till 1960. In the sixties the evolutionary importance of selection has been called in question by the neutralists. The traditional conception of the gene is disarranged by recent molecular-biological findings. Owing to the increasing confusion about the concept of genotype, this concept is reconsidered. The idea of the genotype as a cluster of genes is replaced by a cybernetical interpretation of the genotype. As nature does jump, exclusive gradualism is dismissed. Saltatory evolution is a natural phenomenon, provided by a sudden collapse of the thresholds which resist against evolution. The fossil record and the taxonomic system call for a macromutational interpretation. As Lamarck and Darwin overlooked the resistance of evolutionary thresholds, an alternative evolution model is needed, the first to be constructed on a palaeontological and taxonomic basis.

  8. Biological evolution: Some genetic considerations

    African Journals Online (AJOL)

    Mohammad Saad Zaghloul Salem

    2013-12-08

    Dec 8, 2013 ... cept of evolution, viz. genetic memory and evolutionary variations, genomic adaptations to stress .... or codons, along the transcript without giving attention to whether they are ... They do not affect the genome in a straightfor-.

  9. Weak interactions and presupernova evolution

    International Nuclear Information System (INIS)

    Aufderheide, M.B.; State Univ. of New York

    1991-01-01

    The role of weak interactions, particularly electron capture and β - decay, in presupernova evolution is discussed. The present uncertainty in these rates is examined and the possibility of improving the situation is addressed. 12 refs., 4 figs

  10. Evolution of White Dwarf Stars

    OpenAIRE

    L. G. Althaus

    2001-01-01

    This paper is aimed at presenting the main results we have obtained for the study of the evoution of white dwarf stars. The calculations are carried out by means of a detailed evolutionary code based on an updated physical description. In particular, we briefly discuss the results for the evolution of white dwarfs of different stellar masses and chemical composition, and the evolution of whit e dwarfs in the framework of a varying gravitational constant G scenario as well.

  11. Evolution, religions and global Bioethics

    OpenAIRE

    Perbal, Laurence

    2007-01-01

    Creationist theories are still present in the United States and in Europe. The Darwinian theory of evolution is often considered as the starting point of important debates between religions and evolutionists. In this paper, we are principally interested in evolutionary creationism (or theistic evolutionism). The existence of a divine design in nature, the spiritual status of human beings and the emergence of human species as the purpose of evolution are some of those debates. The post-Darwini...

  12. Physical Complexity and Cognitive Evolution

    Science.gov (United States)

    Jedlicka, Peter

    Our intuition tells us that there is a general trend in the evolution of nature, a trend towards greater complexity. However, there are several definitions of complexity and hence it is difficult to argue for or against the validity of this intuition. Christoph Adami has recently introduced a novel measure called physical complexity that assigns low complexity to both ordered and random systems and high complexity to those in between. Physical complexity measures the amount of information that an organism stores in its genome about the environment in which it evolves. The theory of physical complexity predicts that evolution increases the amount of `knowledge' an organism accumulates about its niche. It might be fruitful to generalize Adami's concept of complexity to the entire evolution (including the evolution of man). Physical complexity fits nicely into the philosophical framework of cognitive biology which considers biological evolution as a progressing process of accumulation of knowledge (as a gradual increase of epistemic complexity). According to this paradigm, evolution is a cognitive `ratchet' that pushes the organisms unidirectionally towards higher complexity. Dynamic environment continually creates problems to be solved. To survive in the environment means to solve the problem, and the solution is an embodied knowledge. Cognitive biology (as well as the theory of physical complexity) uses the concepts of information and entropy and views the evolution from both the information-theoretical and thermodynamical perspective. Concerning humans as conscious beings, it seems necessary to postulate an emergence of a new kind of knowledge - a self-aware and self-referential knowledge. Appearence of selfreflection in evolution indicates that the human brain reached a new qualitative level in the epistemic complexity.

  13. Evolution of the European region

    International Nuclear Information System (INIS)

    Jeger, Eh.

    1984-01-01

    The problem on geochronological study of the European region is covered. The most ancient age values are determined by U-Pb methods by zircones from paragneisses. The model of evolution, being in agreement with the data obtained by U-Pb and Rb-Sr methods, is considered. The history of the Schwarzwald development is typical for the continent as a whole. The diagram of evolution of primary 87 Sr/ 86 Sr for orthogneisses and granites in France is given

  14. Biological evolution: Some genetic considerations

    OpenAIRE

    Salem, Mohammad Saad Zaghloul

    2014-01-01

    Background: The concept of biological evolution has long been accepted as a palatable theory aiming at explaining how life began and how creatures diverged so widely along the life span of the earth. Meticulous analysis and criticism of the different postulations of this concept, however, reveals that evolution is an illogic concept based on theoretical hypotheses that can never be tested. Creation, on the other hand, represents the other side of the coin, and up till now debates confronting ...

  15. Qutrit squeezing via semiclassical evolution

    International Nuclear Information System (INIS)

    Klimov, Andrei B; Dinani, Hossein Tavakoli; Medendorp, Zachari E D; Guise, Hubert de

    2011-01-01

    We introduce a concept of squeezing in collective qutrit systems through a geometrical picture connected to the deformation of the isotropic fluctuations of su(3) operators when evaluated in a coherent state. This kind of squeezing can be generated by Hamiltonians nonlinear in the generators of su(3) algebra. A simplest model of such a nonlinear evolution is analyzed in terms of semiclassical evolution of the SU(3) Wigner function. (paper)

  16. Symmetry and topology in evolution

    International Nuclear Information System (INIS)

    Lukacs, B.; Berczi, S.; Molnar, I.; Paal, G.

    1991-10-01

    This volume contains papers of an interdisciplinary symposium on evolution. The aim of this symposium, held in Budapest, Hungary, 28-29 May 1991, was to clear the role of symmetry and topology at different levels of the evolutionary processes. 21 papers were presented, their topics included evolution of the Universe, symmetry of elementary particles, asymmetry of the Earth, symmetry and asymmetry of biomolecules, symmetry and topology of lining objects, human asymmetry etc. (R.P.)

  17. Entanglement and inhibited quantum evolution

    International Nuclear Information System (INIS)

    Toschek, P E; Balzer, Chr; Hannemann, Th; Wunderlich, Ch; Neuhauser, W

    2003-01-01

    The evolution of a quantum system is impeded by the system's state being observed. A test on an ensemble neither proves the causal nexus nor discloses the nature of the inhibition. Two recent experiments that make use of sequential optical or microwave-optical double resonance on an individual trapped ion disprove a dynamical effect of back action by meter or environment. They rather indicate the ionic states involved in the evolution being entangled with the potentially recorded bivalued scattered-light signal

  18. Thermodynamic evolution far from equilibrium

    Science.gov (United States)

    Khantuleva, Tatiana A.

    2018-05-01

    The presented model of thermodynamic evolution of an open system far from equilibrium is based on the modern results of nonequilibrium statistical mechanics, the nonlocal theory of nonequilibrium transport developed by the author and the Speed Gradient principle introduced in the theory of adaptive control. Transition to a description of the system internal structure evolution at the mesoscopic level allows a new insight at the stability problem of non-equilibrium processes. The new model is used in a number of specific tasks.

  19. The evolution of single stars

    International Nuclear Information System (INIS)

    Tayler, R.J.

    1982-01-01

    The general outline of the evolution of single stars is well understood but at most stages of evolution important uncertainties remain. This paper contains a very personal view of what are the major uncertainties and of what problems remain to be solved before one can be satisfied with the theory. It is suggested that some problems may be essentially insoluble even with the very large and fast computers that are currently available. (author)

  20. Modelling Geomorphic Systems: Landscape Evolution

    OpenAIRE

    Valters, Declan

    2016-01-01

    Landscape evolution models (LEMs) present the geomorphologist with a means of investigating how landscapes evolve in response to external forcings, such as climate and tectonics, as well as internal process laws. LEMs typically incorporate a range of different geomorphic transport laws integrated in a way that simulates the evolution of a 3D terrain surface forward through time. The strengths of LEMs as research tools lie in their ability to rapidly test many different hypotheses of landscape...

  1. Evolution of Isolated Neutron Stars

    OpenAIRE

    Popov, S. B.

    2001-01-01

    In this paper we briefly review our recent results on evolution and properties of isolated neutron stars (INSs) in the Galaxy. As the first step we discuss stochastic period evolution of INSs. We briefly discuss how an INS's spin period evolves under influence of interaction with turbulized interstellar medium. To investigate statistical properties of the INS population we calculate a {\\it census} of INSs in our Galaxy. Then we show that for exponential field decay the range of minimum value ...

  2. Cultural commons and cultural evolution

    OpenAIRE

    Bravo, Giangiacomo

    2010-01-01

    Culture evolves following a process that is akin to biological evolution, although with some significant differences. At the same time culture has often a collective good value for human groups. This paper studies culture in an evolutionary perspective, with a focus on the implications of group definition for the coexistence of different cultures. A model of cultural evolution is presented where agents interacts in an artificial environment. The belonging to a specific memetic group is a majo...

  3. Phylogenomic Insights into Animal Evolution.

    Science.gov (United States)

    Telford, Maximilian J; Budd, Graham E; Philippe, Hervé

    2015-10-05

    Animals make up only a small fraction of the eukaryotic tree of life, yet, from our vantage point as members of the animal kingdom, the evolution of the bewildering diversity of animal forms is endlessly fascinating. In the century following the publication of Darwin's Origin of Species, hypotheses regarding the evolution of the major branches of the animal kingdom - their relationships to each other and the evolution of their body plans - was based on a consideration of the morphological and developmental characteristics of the different animal groups. This morphology-based approach had many successes but important aspects of the evolutionary tree remained disputed. In the past three decades, molecular data, most obviously primary sequences of DNA and proteins, have provided an estimate of animal phylogeny largely independent of the morphological evolution we would ultimately like to understand. The molecular tree that has evolved over the past three decades has drastically altered our view of animal phylogeny and many aspects of the tree are no longer contentious. The focus of molecular studies on relationships between animal groups means, however, that the discipline has become somewhat divorced from the underlying biology and from the morphological characteristics whose evolution we aim to understand. Here, we consider what we currently know of animal phylogeny; what aspects we are still uncertain about and what our improved understanding of animal phylogeny can tell us about the evolution of the great diversity of animal life. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Binary evolution and observational constraints

    International Nuclear Information System (INIS)

    Loore, C. de

    1984-01-01

    The evolution of close binaries is discussed in connection with problems concerning mass and angular momentum losses. Theoretical and observational evidence for outflow of matter, leaving the system during evolution is given: statistics on total masses and mass ratios, effects of the accretion of the mass gaining component, the presence of streams, disks, rings, circumstellar envelopes, period changes, abundance changes in the atmosphere. The effects of outflowing matter on the evolution is outlined, and estimates of the fraction of matter expelled by the loser, and leaving the system, are given. The various time scales involved with evolution and observation are compared. Examples of non conservative evolution are discussed. Problems related to contact phases, on mass and energy losses, in connection with entropy changes are briefly analysed. For advanced stages the disruption probabilities for supernova explosions are examined. A global picture is given for the evolution of massive close binaries, from ZAMS, through WR phases, X-ray phases, leading to runaway pulsars or to a binary pulsar and later to a millisecond pulsar. (Auth.)

  5. Factorizing the time evolution operator

    International Nuclear Information System (INIS)

    Garcia Quijas, P C; Arevalo Aguilar, L M

    2007-01-01

    There is a widespread belief in the quantum physical community, and textbooks used to teach quantum mechanics, that it is a difficult task to apply the time evolution operator e itH-hat/h on an initial wavefunction. Because the Hamiltonian operator is, generally, the sum of two operators, then it is not possible to apply the time evolution operator on an initial wavefunction ψ(x, 0), for it implies using terms like (a-hat + b-hat). A possible solution is to factorize the time evolution operator and then apply successively the individual exponential operator on the initial wavefunction. However, the exponential operator does not directly factorize, i.e. e a-hat+b-hat ≠ e a-hat e b-hat . In this study we present a useful procedure for factorizing the time evolution operator when the argument of the exponential is a sum of two operators, which obey specific commutation relations. Then, we apply the exponential operator as an evolution operator for the case of elementary unidimensional potentials, like a particle subject to a constant force and a harmonic oscillator. Also, we discuss an apparent paradox concerning the time evolution operator and non-spreading wave packets addressed previously in the literature

  6. Plant domestication slows pest evolution.

    Science.gov (United States)

    Turcotte, Martin M; Lochab, Amaneet K; Turley, Nash E; Johnson, Marc T J

    2015-09-01

    Agricultural practices such as breeding resistant varieties and pesticide use can cause rapid evolution of pest species, but it remains unknown how plant domestication itself impacts pest contemporary evolution. Using experimental evolution on a comparative phylogenetic scale, we compared the evolutionary dynamics of a globally important economic pest - the green peach aphid (Myzus persicae) - growing on 34 plant taxa, represented by 17 crop species and their wild relatives. Domestication slowed aphid evolution by 13.5%, maintained 10.4% greater aphid genotypic diversity and 5.6% higher genotypic richness. The direction of evolution (i.e. which genotypes increased in frequency) differed among independent domestication events but was correlated with specific plant traits. Individual-based simulation models suggested that domestication affects aphid evolution directly by reducing the strength of selection and indirectly by increasing aphid density and thus weakening genetic drift. Our results suggest that phenotypic changes during domestication can alter pest evolutionary dynamics. © 2015 John Wiley & Sons Ltd/CNRS.

  7. The Galaxy Evolution Probe

    Science.gov (United States)

    Glenn, Jason; Galaxy Evolution Probe Team

    2018-01-01

    The Galaxy Evolution Probe (GEP) is a concept for a far-infrared observatory to survey large regions of sky for star-forming galaxies from z = 0 to beyond z = 3. Our knowledge of galaxy formation is incomplete and requires uniform surveys over a large range of redshifts and environments to accurately describe mass assembly, star formation, supermassive black hole growth, interactions between these processes, and what led to their decline from z ~ 2 to the present day. Infrared observations are sensitive to dusty, star-forming galaxies, which have bright polycyclic aromatic hydrocarbon (PAH) emission features and warm dust continuum in the rest-frame mid infrared and cooler thermal dust emission in the far infrared. Unlike previous far-infrared continuum surveys, the GEP will measure photometric redshifts commensurate with galaxy detections from PAH emission and Si absorption features, without the need for obtaining spectroscopic redshifts of faint counterparts at other wavelengths.The GEP design includes a 2 m diameter telescope actively cooled to 4 K and two instruments: (1) An imager covering 10 to 300 um with 25 spectral resolution R ~ 8 bands (with lower R at the longest wavelengths) to detect star-forming galaxies and measure their redshifts photometrically. (2) A 23 – 190 um, R ~ 250 dispersive spectrometer for redshift confirmation and identification of obscured AGN using atomic fine-structure lines. Lines including [Ne V], [O IV], [O III], [O I], and [C II] will probe gas physical conditions, radiation field hardness, and metallicity. Notionally, the GEP will have a two-year mission: galaxy surveys with photometric redshifts in the first year and a second year devoted to follow-up spectroscopy. A comprehensive picture of star formation in galaxies over the last 10 billion years will be assembled from cosmologically relevant volumes, spanning environments from field galaxies and groups, to protoclusters, to dense galaxy clusters.Commissioned by NASA, the

  8. Evolution of plant senescence

    Directory of Open Access Journals (Sweden)

    Young Mike

    2009-07-01

    characteristics of senescence-related genes allow a framework to be constructed of decisive events in the evolution of the senescence syndrome of modern land-plants. Combining phylogenetic, comparative sequence, gene expression and morphogenetic information leads to the conclusion that biochemical, cellular, integrative and adaptive systems were progressively added to the ancient primary core process of senescence as the evolving plant encountered new environmental and developmental contexts.

  9. American Muslim Undergraduates' Views on Evolution

    Science.gov (United States)

    Fouad, Khadija Engelbrecht

    2016-01-01

    A qualitative investigation into American Muslim undergraduates' views on evolution revealed three main positions on evolution: theistic evolution, a belief in special creation of all species, and a belief in special creation of humans with evolution for all non-human species. One can conceive of the manner in which respondents chose their…

  10. Student Teachers' Approaches to Teaching Biological Evolution

    Science.gov (United States)

    Borgerding, Lisa A.; Klein, Vanessa A.; Ghosh, Rajlakshmi; Eibel, Albert

    2015-01-01

    Evolution is fundamental to biology and scientific literacy, but teaching high school evolution is often difficult. Evolution teachers face several challenges including limited content knowledge, personal conflicts with evolution, expectations of resistance, concerns about students' conflicts with religion, and curricular constraints. Evolution…

  11. Cyanobacterial evolution during the Precambrian

    Science.gov (United States)

    Schirrmeister, Bettina E.; Sanchez-Baracaldo, Patricia; Wacey, David

    2016-07-01

    Life on Earth has existed for at least 3.5 billion years. Yet, relatively little is known of its evolution during the first two billion years, due to the scarceness and generally poor preservation of fossilized biological material. Cyanobacteria, formerly known as blue green algae were among the first crown Eubacteria to evolve and for more than 2.5 billion years they have strongly influenced Earth's biosphere. Being the only organism where oxygenic photosynthesis has originated, they have oxygenated Earth's atmosphere and hydrosphere, triggered the evolution of plants -being ancestral to chloroplasts- and enabled the evolution of complex life based on aerobic respiration. Having such a strong impact on early life, one might expect that the evolutionary success of this group may also have triggered further biosphere changes during early Earth history. However, very little is known about the early evolution of this phylum and ongoing debates about cyanobacterial fossils, biomarkers and molecular clock analyses highlight the difficulties in this field of research. Although phylogenomic analyses have provided promising glimpses into the early evolution of cyanobacteria, estimated divergence ages are often very uncertain, because of vague and insufficient tree-calibrations. Results of molecular clock analyses are intrinsically tied to these prior calibration points, hence improving calibrations will enable more precise divergence time estimations. Here we provide a review of previously described Precambrian microfossils, biomarkers and geochemical markers that inform upon the early evolution of cyanobacteria. Future research in micropalaeontology will require novel analyses and imaging techniques to improve taxonomic affiliation of many Precambrian microfossils. Consequently, a better understanding of early cyanobacterial evolution will not only allow for a more specific calibration of cyanobacterial and eubacterial phylogenies, but also provide new dates for the tree

  12. Musical emotions: Functions, origins, evolution

    Science.gov (United States)

    Perlovsky, Leonid

    2010-03-01

    Theories of music origins and the role of musical emotions in the mind are reviewed. Most existing theories contradict each other, and cannot explain mechanisms or roles of musical emotions in workings of the mind, nor evolutionary reasons for music origins. Music seems to be an enigma. Nevertheless, a synthesis of cognitive science and mathematical models of the mind has been proposed describing a fundamental role of music in the functioning and evolution of the mind, consciousness, and cultures. The review considers ancient theories of music as well as contemporary theories advanced by leading authors in this field. It addresses one hypothesis that promises to unify the field and proposes a theory of musical origin based on a fundamental role of music in cognition and evolution of consciousness and culture. We consider a split in the vocalizations of proto-humans into two types: one less emotional and more concretely-semantic, evolving into language, and the other preserving emotional connections along with semantic ambiguity, evolving into music. The proposed hypothesis departs from other theories in considering specific mechanisms of the mind-brain, which required the evolution of music parallel with the evolution of cultures and languages. Arguments are reviewed that the evolution of language toward becoming the semantically powerful tool of today required emancipation from emotional encumbrances. The opposite, no less powerful mechanisms required a compensatory evolution of music toward more differentiated and refined emotionality. The need for refined music in the process of cultural evolution is grounded in fundamental mechanisms of the mind. This is why today's human mind and cultures cannot exist without today's music. The reviewed hypothesis gives a basis for future analysis of why different evolutionary paths of languages were paralleled by different evolutionary paths of music. Approaches toward experimental verification of this hypothesis in

  13. Understanding Collateral Evolution in Linux Device Drivers

    DEFF Research Database (Denmark)

    Padioleau, Yoann; Lawall, Julia Laetitia; Muller, Gilles

    2006-01-01

    no tools to help in this process, collateral evolution is thus time consuming and error prone.In this paper, we present a qualitative and quantitative assessment of collateral evolution in Linux device driver code. We provide a taxonomy of evolutions and collateral evolutions, and use an automated patch......-analysis tool that we have developed to measure the number of evolutions and collateral evolutions that affect device drivers between Linux versions 2.2 and 2.6. In particular, we find that from one version of Linux to the next, collateral evolutions can account for up to 35% of the lines modified in such code....

  14. Helicity evolution at small x

    International Nuclear Information System (INIS)

    Kovchegov, Yuri V.; Pitonyak, Daniel; Sievert, Matthew D.

    2016-01-01

    We construct small-x evolution equations which can be used to calculate quark and anti-quark helicity TMDs and PDFs, along with the g 1 structure function. These evolution equations resum powers of α s ln 2  (1/x) in the polarization-dependent evolution along with the powers of α s ln (1/x) in the unpolarized evolution which includes saturation effects. The equations are written in an operator form in terms of polarization-dependent Wilson line-like operators. While the equations do not close in general, they become closed and self-contained systems of non-linear equations in the large-N c and large-N c   N f limits. As a cross-check, in the ladder approximation, our equations map onto the same ladder limit of the infrared evolution equations for the g 1 structure function derived previously by Bartels, Ermolaev and Ryskin http://dx.doi.org/10.1007/s002880050285.

  15. Experimental evolution in biofilm populations

    Science.gov (United States)

    Steenackers, Hans P.; Parijs, Ilse; Foster, Kevin R.; Vanderleyden, Jozef

    2016-01-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  16. The evolution of mollusc shells.

    Science.gov (United States)

    McDougall, Carmel; Degnan, Bernard M

    2018-05-01

    Molluscan shells are externally fabricated by specialized epithelial cells on the dorsal mantle. Although a conserved set of regulatory genes appears to underlie specification of mantle progenitor cells, the genes that contribute to the formation of the mature shell are incredibly diverse. Recent comparative analyses of mantle transcriptomes and shell proteomes of gastropods and bivalves are consistent with shell diversity being underpinned by a rapidly evolving mantle secretome (suite of genes expressed in the mantle that encode secreted proteins) that is the product of (a) high rates of gene co-option into and loss from the mantle gene regulatory network, and (b) the rapid evolution of coding sequences, particular those encoding repetitive low complexity domains. Outside a few conserved genes, such as carbonic anhydrase, a so-called "biomineralization toolkit" has yet to be discovered. Despite this, a common suite of protein domains, which are often associated with the extracellular matrix and immunity, appear to have been independently and often uniquely co-opted into the mantle secretomes of different species. The evolvability of the mantle secretome provides a molecular explanation for the evolution and diversity of molluscan shells. These genomic processes are likely to underlie the evolution of other animal biominerals, including coral and echinoderm skeletons. This article is categorized under: Comparative Development and Evolution > Regulation of Organ Diversity Comparative Development and Evolution > Evolutionary Novelties. © 2018 Wiley Periodicals, Inc.

  17. Chaos and unpredictability in evolution.

    Science.gov (United States)

    Doebeli, Michael; Ispolatov, Iaroslav

    2014-05-01

    The possibility of complicated dynamic behavior driven by nonlinear feedbacks in dynamical systems has revolutionized science in the latter part of the last century. Yet despite examples of complicated frequency dynamics, the possibility of long-term evolutionary chaos is rarely considered. The concept of "survival of the fittest" is central to much evolutionary thinking and embodies a perspective of evolution as a directional optimization process exhibiting simple, predictable dynamics. This perspective is adequate for simple scenarios, when frequency-independent selection acts on scalar phenotypes. However, in most organisms many phenotypic properties combine in complicated ways to determine ecological interactions, and hence frequency-dependent selection. Therefore, it is natural to consider models for evolutionary dynamics generated by frequency-dependent selection acting simultaneously on many different phenotypes. Here we show that complicated, chaotic dynamics of long-term evolutionary trajectories in phenotype space is very common in a large class of such models when the dimension of phenotype space is large, and when there are selective interactions between the phenotypic components. Our results suggest that the perspective of evolution as a process with simple, predictable dynamics covers only a small fragment of long-term evolution. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  18. A new paradigma on the plant evolution: from a natural evolution to an artificial evolution?

    Science.gov (United States)

    Bennici, Andrea

    2005-01-01

    After evidencing the great importance of plants for animals and humans in consequence of the photosynthesis, several considerations on plant evolution are made. One of the peculiar characteristics of the plant is the sessile property, due especially to the cell wall. This factor, principally, strengthened by the photosynthetic process, determined the particular developmental pattern of the plant, which is characterized by the continuous formation of new organs. The plant immobility, although negative for its survival, has been, in great part, overcome by the acquisition of the capacity of adaptation (plasticity) to the environmental stresses and changes, and the establishment of more adapted genotypes. This capacity to react to the external signals induced Trewavas to speak of "plant intelligence". The plant movement incapacity and the evolution of the sexual reproduction system were strongly correlated. In this context, the evolution of the flower in the Angiosperms has been particularly important to allow the male gamete to fertilize the immobile female gamete. Moreover, the formation of fruit and seed greatly improved the dispersal and conservation of the progeny in the environment. With the flower, mechanisms to favour the outcrossing among different individuals appeared, which are essential to increase the genetic variability and, then, the plant evolution itself. Although the Angiosperms seem highly evolved, the plant evolution is not surely finished, because many reported morpho-physiological processes may be still considered susceptible of further improvement. In the last years the relationships among humans, plants and environment are becoming closer and closer. This is due to the use of the DNA recombinant techniques with the aim to modify artificially plant characters. Therefore, the risk of a plant evolution strongly directed towards practical or commercial objectives, or "an artificial evolution", may be hypothesized.

  19. GENUSA Fuel Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Choithramani, Sylvia; Malpica, Maria [ENUSA Industrias Avanzadas, GENUSA, Josefa Valcarcel, 26 28027 Madrid (Spain); Fawcett, Russel [Global Nuclear Fuel (United States)

    2009-06-15

    surface specifications to add PCI margin; - Introduction of a debris filter, applied as a standard feature to 10x10 GE14, and as an optional feature in 9x9 fuel, to address debris fretting, as well as advancements to debris filters to achieve even better resistance to debris ingress. GENUSA has always taken the necessary steps to assure the infrastructure and technology are in place to support each product or potential product introduction program. This paper will describe these steps and the evolution of the GENUSA delivered product in Europe starting with the first Garona reload product and finish with a slight description of how our latest product, GNF2, was born. This will include how GENUSA opened to the European market and all the different products that GENUSA has offered and offers nowadays. (authors)

  20. Extinction Events Can Accelerate Evolution

    DEFF Research Database (Denmark)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate...... evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending...... computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific...

  1. Evolution of the Cosmic Web

    Science.gov (United States)

    Einasto, J.

    2017-07-01

    In the evolution of the cosmic web dark energy plays an important role. To understand the role of dark energy we investigate the evolution of superclusters in four cosmological models: standard model SCDM, conventional model LCDM, open model OCDM, and a hyper-dark-energy model HCDM. Numerical simulations of the evolution are performed in a box of size 1024 Mpc/h. Model superclusters are compared with superclusters found for Sloan Digital Sky Survey (SDSS). Superclusters are searched using density fields. LCDM superclusters have properties, very close to properties of observed SDSS superclusters. Standard model SCDM has about 2 times more superclusters than other models, but SCDM superclusters are smaller and have lower luminosities. Superclusters as principal structural elements of the cosmic web are present at all cosmological epochs.

  2. Evolution equations for Killing fields

    International Nuclear Information System (INIS)

    Coll, B.

    1977-01-01

    The problem of finding necessary and sufficient conditions on the Cauchy data for Einstein equations which insure the existence of Killing fields in a neighborhood of an initial hypersurface has been considered recently by Berezdivin, Coll, and Moncrief. Nevertheless, it can be shown that the evolution equations obtained in all these cases are of nonstrictly hyperbolic type, and, thus, the Cauchy data must belong to a special class of functions. We prove here that, for the vacuum and Einstein--Maxwell space--times and in a coordinate independent way, one can always choose, as evolution equations for the Killing fields, a strictly hyperbolic system: The above theorems can be thus extended to all Cauchy data for which the Einstein evolution problem has been proved to be well set

  3. Modelling microstructural evolution under irradiation

    International Nuclear Information System (INIS)

    Tikare, V.

    2015-01-01

    Microstructural evolution of materials under irradiation is characterised by some unique features that are not typically present in other application environments. While much understanding has been achieved by experimental studies, the ability to model this microstructural evolution for complex materials states and environmental conditions not only enhances understanding, it also enables prediction of materials behaviour under conditions that are difficult to duplicate experimentally. Furthermore, reliable models enable designing materials for improved engineering performance for their respective applications. Thus, development and application of mesoscale microstructural model are important for advancing nuclear materials technologies. In this chapter, the application of the Potts model to nuclear materials will be reviewed and demonstrated, as an example of microstructural evolution processes. (author)

  4. The evolution of the elements

    International Nuclear Information System (INIS)

    Williams, P.M.

    1978-01-01

    It is believed that only the lightest elements, hydrogen and helium, were created during the 'Big Bang' origin of the Universe and that all heavier elements were synthesized by nuclear reactions in stars, the interstellar medium and possibly in 'little bangs' in the nuclei of galaxies. The composition of the interstellar medium has evolved through enrichment by processed material shed by evolving stars and the composition of the Solar System reflects that of the interstellar medium at the time of its formation. Differentiation processes during the evolution of the Solar System and individual planets account for the different compositions of the Sun and the planets. The measurement of the abundance distribution of the elements has become a very powerful tool in the elucidation of the evolution of the Solar System, stars and the Galaxy. This review attempts to trace the formation of the elements in stars and their subsequent evolution. (author)

  5. Darwinian evolution on a chip.

    Directory of Open Access Journals (Sweden)

    Brian M Paegel

    2008-04-01

    Full Text Available Computer control of Darwinian evolution has been demonstrated by propagating a population of RNA enzymes in a microfluidic device. The RNA population was challenged to catalyze the ligation of an oligonucleotide substrate under conditions of progressively lower substrate concentrations. A microchip-based serial dilution circuit automated an exponential growth phase followed by a 10-fold dilution, which was repeated for 500 log-growth iterations. Evolution was observed in real time as the population adapted and achieved progressively faster growth rates over time. The final evolved enzyme contained a set of 11 mutations that conferred a 90-fold improvement in substrate utilization, coinciding with the applied selective pressure. This system reduces evolution to a microfluidic algorithm, allowing the experimenter to observe and manipulate adaptation.

  6. Reversible evolution of charged ergoregions

    Energy Technology Data Exchange (ETDEWEB)

    Kokkotas, K.; Spyrou, N.

    1987-07-01

    The reversible evolution of a charged rotating ergoregion, due to the injection into it of particles with mass-energy and angular momentum, is studied systematically. As in the uncharged case, a bulge always forms on the outer boundary of the ergoregion due to the latter's angular momentum. The behavior of the bulge's position, relative to the black hole's rotation axis and equatorial plane, is studied, on the basis of the cosmic censorship hypothesis, during the ergoregion's reversible evolution. The range of the permitted values of the ergoregion's linear dimensions along the rotation axis and perpendicular to it is specified. Finally the differences with the evolution of an uncharged ergoregion are pointed out and discussed.

  7. Institutional Evolution and Corporate Boards

    DEFF Research Database (Denmark)

    Chen, Victor Zitian; Hobdari, Bersant; Sun, Pei

    2014-01-01

    We argue that corporate boards are a dynamic repository of human- and social capital in response to external institutional evolution. Theoretically, integrating institutional economics, agency theory and resource dependence theory, we explain that evolution of market-, legal- and political......, since the board changes are typically proposed by the block shareholders, whose motivation for doing so is closely associated with a corporation’s financial performance, we further argue that financial performance is a key moderator of the relationships between institutional evolution and changes...... institutions restructures the particular context in which board members play their two primary roles: monitoring the CEO on behalf of the shareholders, suggested by the agency theory, and supporting the CEO by providing resources, knowledge and information, suggested by the resource dependence theory...

  8. Online evolution of robot behaviour

    OpenAIRE

    Silva, Fernando Goulart da

    2012-01-01

    Tese de mestrado em Engenharia Informática (Interação e Conhecimento), apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2012 In this dissertation, we propose and evaluate two novel approaches to the online synthesis of neural controllers for autonomous robots. The first approach is odNEAT, an online, distributed, and decentralized version of NeuroEvolution of Augmenting Topologies (NEAT). odNEAT is an algorithm for online evolution in groups of embodied agents such a...

  9. Evolution in close binary systems

    International Nuclear Information System (INIS)

    Yungel'son, L.R.; Masevich, A.G.

    1983-01-01

    Duality is the property most typical of stars. If one investigates how prevalent double stars are, making due allowance for selection effects, one finds that as many as 90 percent of all stars are paired. Contrary to tradition it is single stars that are out of the ordinary, and as will be shown presently even some of these may have been formed by coalescence of the members of binary systems. This review deals with the evolution of close binaries, defined as double-star systems whose evolution entails exchange of material between the two components

  10. Entanglement and inhibited quantum evolution

    Energy Technology Data Exchange (ETDEWEB)

    Toschek, P E; Balzer, Chr; Hannemann, Th; Wunderlich, Ch; Neuhauser, W [Universitaet Hamburg, Institut fuer Laser-Physik, Jungiusstrasse 9, D-20355 Hamburg (Germany)

    2003-03-14

    The evolution of a quantum system is impeded by the system's state being observed. A test on an ensemble neither proves the causal nexus nor discloses the nature of the inhibition. Two recent experiments that make use of sequential optical or microwave-optical double resonance on an individual trapped ion disprove a dynamical effect of back action by meter or environment. They rather indicate the ionic states involved in the evolution being entangled with the potentially recorded bivalued scattered-light signal.

  11. Explaining the Evolution of Poverty

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Azhar; Jones, Edward Samuel

    2012-01-01

    We provide a comprehensive approach for analyzing the evolution of poverty using Mozambique as a case study. Bringing together data from disparate sources, we develop a novel “back-casting” framework that links a dynamic computable general equilibrium model to a micro-simulation poverty module....... This framework provides a new approach to explaining and decomposing the evolution of poverty, as well as to examining rigorously the coherence between poverty, economic growth, and inequality outcomes. Finally, various simple but useful and rarely-applied approaches to considering regional changes in poverty...

  12. Experimental evolution of E. coli

    Science.gov (United States)

    Zhang, Mengshi

    The evolution from unicellular to multicellular behavior is an essential step in the history of life. Our aim is to investigate the emergence of collective behavior in the model organism Escherichia coli (E. coli) and its selection advantages, such as better utilization of public goods. Our preliminary results suggest that the evolution of collective behavior may be a natural response to stressed conditions. Mailing address: Room 306 Science Centre North Block, The Chinese University of Hong Kong, Shatin, N.T. Hong Kong SAR. Phone: +852-3943-6354. Fax: +852-2603-5204. E-mail: mengshi0928@gmail.com.

  13. Statistical and physical evolution of QSO's

    International Nuclear Information System (INIS)

    Caditz, D.; Petrosian, V.

    1989-09-01

    The relationship between the physical evolution of discrete extragalactic sources, the statistical evolution of the observed population of sources, and the cosmological model is discussed. Three simple forms of statistical evolution: pure luminosity evolution (PLE), pure density evolution (PDE), and generalized luminosity evolution (GLE), are considered in detail together with what these forms imply about the physical evolution of individual sources. Two methods are used to analyze the statistical evolution of the observed distribution of QSO's (quasars) from combined flux limited samples. It is shown that both PLE and PDE are inconsistent with the data over the redshift range 0 less than z less than 2.2, and that a more complicated form of evolution such as GLE is required, independent of the cosmological model. This result is important for physical models of AGN, and in particular, for the accretion disk model which recent results show may be inconsistent with PLE

  14. Student Teachers' Approaches to Teaching Biological Evolution

    Science.gov (United States)

    Borgerding, Lisa A.; Klein, Vanessa A.; Ghosh, Rajlakshmi; Eibel, Albert

    2015-06-01

    Evolution is fundamental to biology and scientific literacy, but teaching high school evolution is often difficult. Evolution teachers face several challenges including limited content knowledge, personal conflicts with evolution, expectations of resistance, concerns about students' conflicts with religion, and curricular constraints. Evolution teaching can be particularly challenging for student teachers who are just beginning to gain pedagogical knowledge and pedagogical content knowledge related to evolution teaching and who seek approval from university supervisors and cooperating teachers. Science teacher educators need to know how to best support student teachers as they broach the sometimes daunting task of teaching evolution within student teaching placements. This multiple case study report documents how three student teachers approached evolution instruction and what influenced their approaches. Data sources included student teacher interviews, field note observations for 4-5 days of evolution instruction, and evolution instructional artifacts. Data were analyzed using grounded theory approaches to develop individual cases and a cross-case analysis. Seven influences (state exams and standards, cooperating teacher, ideas about teaching and learning, concerns about evolution controversy, personal commitment to evolution, knowledge and preparation for teaching evolution, and own evolution learning experiences) were identified and compared across cases. Implications for science teacher preparation and future research are provided.

  15. Evolution of energy conversion plants

    International Nuclear Information System (INIS)

    Osnaghi, C.

    2001-01-01

    The paper concerns the evolution and the future development of energy conversion plants and puts into evidence the great importance of the scientific and technological improvement in machines design, in order to optimize the use of energy resources and to improve ambient compatibility [it

  16. Time evolution in quantum cosmology

    International Nuclear Information System (INIS)

    Lawrie, Ian D.

    2011-01-01

    A commonly adopted relational account of time evolution in generally covariant systems, and more specifically in quantum cosmology, is argued to be unsatisfactory, insofar as it describes evolution relative to observed readings of a clock that does not exist as a bona fide observable object. A modified strategy is proposed, in which evolution relative to the proper time that elapses along the worldline of a specific observer can be described through the introduction of a ''test clock,'' regarded as internal to, and hence unobservable by, that observer. This strategy is worked out in detail in the case of a homogeneous cosmology, in the context of both a conventional Schroedinger quantization scheme, and a 'polymer' quantization scheme of the kind inspired by loop quantum gravity. Particular attention is given to limitations placed on the observability of time evolution by the requirement that a test clock should contribute only a negligible energy to the Hamiltonian constraint. It is found that suitable compromises are available, in which the clock energy is reasonably small, while Dirac observables are reasonably sharply defined.

  17. Adaptive evolution in ecological communities.

    Directory of Open Access Journals (Sweden)

    Martin M Turcotte

    Full Text Available Understanding how natural selection drives evolution is a key challenge in evolutionary biology. Most studies of adaptation focus on how a single environmental factor, such as increased temperature, affects evolution within a single species. The biological relevance of these experiments is limited because nature is infinitely more complex. Most species are embedded within communities containing many species that interact with one another and the physical environment. To understand the evolutionary significance of such ecological complexity, experiments must test the evolutionary impact of interactions among multiple species during adaptation. Here we highlight an experiment that manipulates species composition and tracks evolutionary responses within each species, while testing for the mechanisms by which species interact and adapt to their environment. We also discuss limitations of previous studies of adaptive evolution and emphasize how an experimental evolution approach can circumvent such shortcomings. Understanding how community composition acts as a selective force will improve our ability to predict how species adapt to natural and human-induced environmental change.

  18. Temperature evolution during dissipative collapse

    Indian Academy of Sciences (India)

    Abstract. We investigate the gravitational collapse of a radiating sphere evolving into a final static configuration described by the interior Schwarzschild solution. The temperature profiles of this par- ticular model are obtained within the framework of causal thermodynamics. The overall temperature evolution is enhanced by ...

  19. The evolution of tensor polarization

    International Nuclear Information System (INIS)

    Huang, H.; Lee, S.Y.; Ratner, L.

    1993-01-01

    By using the equation of motion for the vector polarization, the spin transfer matrix for spin tensor polarization, the spin transfer matrix for spin tensor polarization is derived. The evolution equation for the tensor polarization is studied in the presence of an isolate spin resonance and in the presence of a spin rotor, or snake

  20. Evolution of planetary nebula nuclei

    International Nuclear Information System (INIS)

    Shaw, R.A.

    1985-01-01

    The evolution of planetary nebula nuclei (PNNs) is examined with the aid of the most recent available stellar evolution calculations and new observations of these objects. Their expected distribution in the log L-log T plane is calculated based upon the stellar evolutionary models of Paczynski, Schoenberner and Iben, the initial mass function derived by Miller and Scalo, and various assumptions concerning mass loss during post-main sequence evolution. The distribution is found to be insensitive both to the assumed range of main-sequence progenitor mass and to reasonable variations in the age and the star forming history of the galactic disk. Rather, the distribution is determined by the strong dependence of the rate of stellar evolution upon core mass, the steepness of the initial mass function, and to a lesser extent the finite lifetime of an observable planetary nebula. The theoretical distributions are rather different than any of those inferred from earlier observations. Possible observational selection effects that may be responsible are examined, as well as the intrinsic uncertainties associated with the theoretical model predictions. An extensive photometric and smaller photographic survey of southern hemisphere planetary nebulae (PNs) is presented

  1. Nonlocal higher order evolution equations

    KAUST Repository

    Rossi, Julio D.; Schö nlieb, Carola-Bibiane

    2010-01-01

    In this article, we study the asymptotic behaviour of solutions to the nonlocal operator ut(x, t)1/4(-1)n-1 (J*Id -1)n (u(x, t)), x ∈ ℝN, which is the nonlocal analogous to the higher order local evolution equation vt(-1)n-1(Δ)nv. We prove

  2. Topology evolution in macromolecular networks

    NARCIS (Netherlands)

    Kryven, I.

    2014-01-01

    Governed by various intermolecular forces, molecular networks tend to evolve from simple to very complex formations that have random structure. This randomness in the connectivity of the basic units can still be captured employing distributional description of the state of the system; the evolution

  3. Evolution of Karyotypes in Chameleons

    Czech Academy of Sciences Publication Activity Database

    Rovatsos, M.; Altmanová, M.; Johnson Pokorná, Martina; Velenský, P.; Baca, A. S.; Kratochvíl, L.

    2017-01-01

    Roč. 8, č. 12 (2017), č. článku 382. ISSN 2073-4425 Institutional support: RVO:67985904 Keywords : karyotype evolution * ITS * rDNA Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 3.600, year: 2016

  4. The Evolution of Scientific Knowledge

    DEFF Research Database (Denmark)

    Jensen, Hans Siggaard; Ricard, Lykke Margot; Vendelø, Morten Thanning

    The Evolution of Scientific Knowledge aims to reach a unique understanding of science with the help of economic and sociological theories. They use institutional and evolutionary theories and the sociological theories draw from the type of work on social studies of science that have, in recent...

  5. The Semiosic Evolution of Education

    Science.gov (United States)

    Olteanu, Alin

    2014-01-01

    The recent development of biosemiotics has revealed the achievement of knowledge and the development of science to be the results of the semiosis of all life forms, including those commonly regarded as cultural constructs. Education is thus a semiosic structure to which evolution itself has adapted, while learning is the semiotic phenomenon that…

  6. The evolution of nuclear regulation

    International Nuclear Information System (INIS)

    Martin, A.

    1997-01-01

    The already not so young history of nuclear regulations shows patterns and specific causes that have characterized and influenced its own evolution as well as the industry itself. Today's regulation is facing relevant challenges with potential significant effects. The quest for higher regulatory efficiency brings up the increasing need to base future actions on firmly established strategies. (Author) 7 refs

  7. Evolution of Deeply Embedded Protostars

    DEFF Research Database (Denmark)

    Frimann, Søren

    consequences for the evolution of protostellar systems. The sublimation of CO-ice from dust grains in the surrounding envelope can be used to trace accretion variability in protostars, because the increased heating during an accretion burst will cause the CO-ice to sublimate into the gas-phase where the excess...

  8. Adaptive evolution of molecular phenotypes

    International Nuclear Information System (INIS)

    Held, Torsten; Nourmohammad, Armita; Lässig, Michael

    2014-01-01

    Molecular phenotypes link genomic information with organismic functions, fitness, and evolution. Quantitative traits are complex phenotypes that depend on multiple genomic loci. In this paper, we study the adaptive evolution of a quantitative trait under time-dependent selection, which arises from environmental changes or through fitness interactions with other co-evolving phenotypes. We analyze a model of trait evolution under mutations and genetic drift in a single-peak fitness seascape. The fitness peak performs a constrained random walk in the trait amplitude, which determines the time-dependent trait optimum in a given population. We derive analytical expressions for the distribution of the time-dependent trait divergence between populations and of the trait diversity within populations. Based on this solution, we develop a method to infer adaptive evolution of quantitative traits. Specifically, we show that the ratio of the average trait divergence and the diversity is a universal function of evolutionary time, which predicts the stabilizing strength and the driving rate of the fitness seascape. From an information-theoretic point of view, this function measures the macro-evolutionary entropy in a population ensemble, which determines the predictability of the evolutionary process. Our solution also quantifies two key characteristics of adapting populations: the cumulative fitness flux, which measures the total amount of adaptation, and the adaptive load, which is the fitness cost due to a population's lag behind the fitness peak. (paper)

  9. The Evolution of Learning Mechanisms.

    Science.gov (United States)

    Garcia, John; Garcia y Robertson, Rodrigo

    This paper introduces seven principles of learning, enduring over the last five centuries of psychological thought, to discuss the evolution of the "Biophyche" (the brain in action) in the development of humans and other large organisms. It describes the conditioning theories of Darwin, Pavlov, and Thorndike and critically reviews the…

  10. Gas Evolution in Protoplanetary Disks

    NARCIS (Netherlands)

    Woitke, Peter; Dent, Bill; Thi, Wing-Fai; Sibthorpe, Bruce; Rice, Ken; Williams, Jonathan; Sicilia-Aguilar, Aurora; Brown, Joanna; Kamp, Inga; Pascucci, Ilaria; Alexander, Richard; Roberge, Aki

    2009-01-01

    This article summarizes a Splinter Session at the Cool Stars XV conference in St. Andrews with 3 review and 4 contributed talks. The speakers have discussed various approaches to understand the structure and evolution of the gas component in protoplanetary disks. These ranged from observational

  11. The evolution of Saccharomycotina yeasts

    Science.gov (United States)

    Associations between traits are prevalent in nature, occurring across a diverse range of taxa and traits. The evolution of trait correlations can be driven by factors intrinsic or extrinsic to an organism, but few studies, especially in microbes, have simultaneously investigated both across a broad ...

  12. Climatic Change and Human Evolution.

    Science.gov (United States)

    Garratt, John R.

    1995-01-01

    Traces the history of the Earth over four billion years, and shows how climate has had an important role to play in the evolution of humans. Posits that the world's rapidly growing human population and its increasing use of energy is the cause of present-day changes in the concentrations of greenhouse gases in the atmosphere. (Author/JRH)

  13. The Evolution of Electronic Publishing.

    Science.gov (United States)

    Lancaster, F. W.

    1995-01-01

    Discusses the evolution of electronic publishing from the early 1960s when computers were used merely to produce conventional printed products to the present move toward networked scholarly publishing. Highlights include library development, periodicals on the Internet, online journals versus paper journals, problems, and the future of…

  14. Social evolution: reciprocity there is.

    Science.gov (United States)

    Taborsky, Michael

    2013-06-03

    The theory of cooperation predicts that altruism can be established by reciprocity, yet empirical evidence from nature is contentious. Increasingly though, experimental results from social vertebrates challenge the nearly exclusive explanatory power of relatedness for the evolution of cooperation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A simple model for binary star evolution

    International Nuclear Information System (INIS)

    Whyte, C.A.; Eggleton, P.P.

    1985-01-01

    A simple model for calculating the evolution of binary stars is presented. Detailed stellar evolution calculations of stars undergoing mass and energy transfer at various rates are reported and used to identify the dominant physical processes which determine the type of evolution. These detailed calculations are used to calibrate the simple model and a comparison of calculations using the detailed stellar evolution equations and the simple model is made. Results of the evolution of a few binary systems are reported and compared with previously published calculations using normal stellar evolution programs. (author)

  16. Evolution of energy structures; Evolution des structures energetiques

    Energy Technology Data Exchange (ETDEWEB)

    Nifenecker, H. [Centre National de la Recherche Scientifique (CNRS), 38 - Grenoble (France)

    2005-07-01

    Because of the big inertia and long time constants of energy systems, their long-time behaviour is mainly determined by their present day state and by the trends of their recent evolution. For this reason, it is of prime importance to foresee the evolution of the different energy production sources which may play an important role in the future. A status of the world energy consumption and production is made first using the energy statistics of the IEA. Then, using the trends observed since 1973, the consequences of a simple extrapolation of these trends is examined. Finally, the scenarios of forecasting of energy structures, like those supplied by the International institute for applied systems analysis (IIASA) are discussed. (J.S.)

  17. Cognitive Evolution and Religion: Cognition and Religious Evolution

    Directory of Open Access Journals (Sweden)

    Harvey Whitehouse

    2016-03-01

    Full Text Available This paper presents contemporary cognitive approaches to the evolution of religious beliefs. Arguments are put forward that different types of beliefs, or ‘modes of religiosity’, occur as a result of a number of evolutionary factors (biological, cultural, socio-political etc. At the same time, religions across the world retain a significant level of common and shared elements, also explained in evolutionary terms.

  18. Relation between Hydrogen Evolution and Hydrodesulfurization Catalysis

    DEFF Research Database (Denmark)

    Šaric, Manuel; Moses, Poul Georg; Rossmeisl, Jan

    2016-01-01

    A relation between hydrogen evolution and hydrodesulfurization catalysis was found by density functional theory calculations. The hydrogen evolution reaction and the hydrogenation reaction in hydrodesulfurization share hydrogen as a surface intermediate and, thus, have a common elementary step...

  19. A comparison of biological and cultural evolution

    Indian Academy of Sciences (India)

    the intellectual and moral characters of man have emerged as results of biological ..... tural selection is at least partly based on conscious action. In cultural evolution .... Transfer of information in biological and cultural evolution. In biological.

  20. Spectral evolution of galaxies: current views

    International Nuclear Information System (INIS)

    Bruzual, A.G.

    1985-01-01

    A summary of current views on the interpretation of the various evolutionary tests aimed at detecting spectral evolution in galaxies is presented. It is concluded that the evolution taking place in known galaxy samples is a slow process (perhaps consistent with no evolution at all), and that the early phases of rapid spectral evolution in early-type galaxies have not yet been detected. (author)

  1. Florida Teachers' Attitudes about Teaching Evolution

    Science.gov (United States)

    Fowler, Samantha R.; Meisels, Gerry G.

    2010-01-01

    A survey of Florida teachers reveals many differences in comfort level with teaching evolution according to the state's science teaching standards, general attitudes and beliefs about evolution, and the extent to which teachers are criticized, censured, disparaged, or reprehended for their beliefs about the teaching of evolution.

  2. Nonlinear Evolution of Alfvenic Wave Packets

    Science.gov (United States)

    Buti, B.; Jayanti, V.; Vinas, A. F.; Ghosh, S.; Goldstein, M. L.; Roberts, D. A.; Lakhina, G. S.; Tsurutani, B. T.

    1998-01-01

    Alfven waves are a ubiquitous feature of the solar wind. One approach to studying the evolution of such waves has been to study exact solutions to approximate evolution equations. Here we compare soliton solutions of the Derivative Nonlinear Schrodinger evolution equation (DNLS) to solutions of the compressible MHD equations.

  3. Evolution of the spherical clusters

    International Nuclear Information System (INIS)

    Surdin, V.G.

    1978-01-01

    The possible processes of the Galaxy spherical clusters formation and evolution are described on a popular level. The orbits of spherical cluster motion and their spatial velocities are determined. Given are the distrbutions of spherical cluster stars according to their velocities and the observed distribution of spherical clusters in the area of the Galaxy slow evolution. The dissipation and dynamic friction processes destructing clusters with the mass less than 10 4 of solar mass and bringing about the reduction of clusters in the Galaxy are considered. The paradox of forming mainly X-ray sources in spherical clusters is explained. The schematic image of possible ways of forming X-ray sources in spherical clusters is given

  4. Automatic schema evolution in Root

    International Nuclear Information System (INIS)

    Brun, R.; Rademakers, F.

    2001-01-01

    ROOT version 3 (spring 2001) supports automatic class schema evolution. In addition this version also produces files that are self-describing. This is achieved by storing in each file a record with the description of all the persistent classes in the file. Being self-describing guarantees that a file can always be read later, its structure browsed and objects inspected, also when the library with the compiled code of these classes is missing. The schema evolution mechanism supports the frequent case when multiple data sets generated with many different class versions must be analyzed in the same session. ROOT supports the automatic generation of C++ code describing the data objects in a file

  5. Quasistatic evolution of compact toroids

    International Nuclear Information System (INIS)

    Sgro, A.G.; Spencer, R.L.; Lilliequist, C.

    1981-01-01

    Some results are presented of simulations of the post formation evolution of compact toroids. The simulations were performed with a 1-1/2 D transport code. Such a code makes explicit use of the fact that the shapes of the flux surfaces in the plasma change much more slowly than do the profiles of the physical variables across the flux surfaces. Consequently, assuming that the thermodynamic variables are always equilibrated on a flux surface, one may calculate the time evolution of these profiles as a function of a single variable that labels the flux surfaces. Occasionally, during the calculation these profiles are used to invert the equilibrium equation to update the shapes of the flux surfaces. In turn, these shapes imply certain geometric cofficients, such as A = 2 >, which contain the geometric information required by the 1-D equations

  6. Automatic Detection of Terminology Evolution

    Science.gov (United States)

    Tahmasebi, Nina

    As archives contain documents that span over a long period of time, the language used to create these documents and the language used for querying the archive can differ. This difference is due to evolution in both terminology and semantics and will cause a significant number of relevant documents being omitted. A static solution is to use query expansion based on explicit knowledge banks such as thesauri or ontologies. However as we are able to archive resources with more varied terminology, it will be infeasible to use only explicit knowledge for this purpose. There exist only few or no thesauri covering very domain specific terminologies or slang as used in blogs etc. In this Ph.D. thesis we focus on automatically detecting terminology evolution in a completely unsupervised manner as described in this technical paper.

  7. [Evolution of education in nursing].

    Science.gov (United States)

    Clavijo Chamorro, María Zoraida; Romero de Julián, Francisco Javier; Paniagua Vivas, María Sandra

    2016-07-26

    This study focuses on investigating the evolution of nursing studies in order to know how much this transformation has contributed to the development of the nursing profession. Literature review with data sources from different national and international databases. These sources provide an update on the ongoing evolution of nursing studies and the progress of this profession as a result of change. The competencies and skills that add value to the nursing profession are: an evidence-based practice; empathic communication; and other broad-range skills such as critical thinking. All are necessary in order to develop the profession alongside the constant changes in the health systems and the improvement of quality care. These competencies and skills should be evaluated and their achievement is being reached through the "portfolio". Innovations that enable the development of these skills can be found in education, strategies and tools used by educators and institutions.

  8. Gravitational lenses and cosmological evolution

    International Nuclear Information System (INIS)

    Peacock, J.A.

    1982-01-01

    The effect of gravitational lensing on the apparent cosmological evolution of extragalactic radio sources is investigated. Models for a lens population consisting of galaxies and clusters of galaxies are constructed and used to calculate the distribution of amplification factors caused by lensing. Although many objects at high redshifts are predicted to have flux densities altered by 10 to 20 per cent relative to a homogeneous universe, flux conservation implies that de-amplification is as common as amplification. The effects on cosmological evolution as inferred from source counts and redshift data are thus relatively small; the slope of the counts is not large enough for intrinsically rare lensing events of high amplitude to corrupt observed samples. Lensing effects may be of greater importance for optically selected quasars, where lenses of mass as low as approximately 10 -4 solar mass can cause large amplifications. (author)

  9. Evolution of radiotherapy at MOH

    International Nuclear Information System (INIS)

    Passi, Kamalesh

    2016-01-01

    Mohan Dai Oswal Cancer Institute was started by Oswals, a philanthropist family of industrialists, in the memory of their mother Smt Mohan Dai Oswal, who died of cancer. This was the first of its kind charitable institute in the private sector in north providing comprehensive cancer care under one roof. The large number of patients that the hospital attracted in the very first year revealed the huge lacuna in cancer care that had been existent in the region. Since then this hospital has been catering to all of Punjab, Himachal, J and K and a large area of Haryana. It has built a reputation for high-tech, yet cost-effective, care. There are multiple dimensions to the evolution of Radiotherapy at MDOH- build-up of technical hardware, growth of skilled personnel, laying down and development of protocols and processes and the evolution of a unique work culture

  10. Evolution in bouncing quantum cosmology

    International Nuclear Information System (INIS)

    Mielczarek, Jakub; Piechocki, Włodzimierz

    2012-01-01

    We present the method of describing an evolution in quantum cosmology in the framework of the reduced phase space quantization of loop cosmology. We apply our method to the flat Friedmann-Robertson-Walker model coupled to a massless scalar field. We identify the physical quantum Hamiltonian that is positive-definite and generates globally a unitary evolution of the considered quantum system. We examine the properties of expectation values of physical observables in the process of the quantum big bounce transition. The dispersion of evolved observables is studied for the Gaussian state. Calculated relative fluctuations enable an examination of the semi-classicality conditions and possible occurrence of the cosmic forgetfulness. Preliminary estimations based on the cosmological data suggest that there was no cosmic amnesia. Presented results are analytical, and numerical computations are only used for the visualization purposes. Our method may be generalized to sophisticated cosmological models including the Bianchi-type universes. (paper)

  11. Chaotic evolution of arms races

    Science.gov (United States)

    Tomochi, Masaki; Kono, Mitsuo

    1998-12-01

    A new set of model equations is proposed to describe the evolution of the arms race, by extending Richardson's model with special emphases that (1) power dependent defensive reaction or historical enmity could be a motive force to promote armaments, (2) a deterrent would suppress the growth of armaments, and (3) the defense reaction of one nation against the other nation depends nonlinearly on the difference in armaments between two. The set of equations is numerically solved to exhibit stationary, periodic, and chaotic behavior depending on the combinations of parameters involved. The chaotic evolution is realized when the economic situation of each country involved in the arms race is quite different, which is often observed in the real world.

  12. Five Misunderstandings About Cultural Evolution.

    Science.gov (United States)

    Henrich, Joseph; Boyd, Robert; Richerson, Peter J

    2008-06-01

    Recent debates about memetics have revealed some widespread misunderstandings about Darwinian approaches to cultural evolution. Drawing from these debates, this paper disputes five common claims: (1) mental representations are rarely discrete, and therefore models that assume discrete, gene-like particles (i.e., replicators) are useless; (2) replicators are necessary for cumulative, adaptive evolution; (3) content-dependent psychological biases are the only important processes that affect the spread of cultural representations; (4) the "cultural fitness" of a mental representation can be inferred from its successful transmission; and (5) selective forces only matter if the sources of variation are random. We close by sketching the outlines of a unified evolutionary science of culture.

  13. Historical Evolution of Spatial Abilities

    Directory of Open Access Journals (Sweden)

    A. Ardila

    1993-01-01

    Full Text Available Historical evolution and cross-cultural differences in spatial abilities are analyzed. Spatial abilities have been found to be significantly associated with the complexity of geographical conditions and survival demands. Although impaired spatial cognition is found in cases of, exclusively or predominantly, right hemisphere pathology, it is proposed that this asymmetry may depend on the degree of training in spatial abilities. It is further proposed that spatial cognition might have evolved in a parallel way with cultural evolution and environmental demands. Contemporary city humans might be using spatial abilities in some new, conceptual tasks that did not exist in prehistoric times: mathematics, reading, writing, mechanics, music, etc. Cross-cultural analysis of spatial abilities in different human groups, normalization of neuropsychological testing instruments, and clinical observations of spatial ability disturbances in people with different cultural backgrounds and various spatial requirements, are required to construct a neuropsychological theory of brain organization of spatial cognition.

  14. Machine learning for evolution strategies

    CERN Document Server

    Kramer, Oliver

    2016-01-01

    This book introduces numerous algorithmic hybridizations between both worlds that show how machine learning can improve and support evolution strategies. The set of methods comprises covariance matrix estimation, meta-modeling of fitness and constraint functions, dimensionality reduction for search and visualization of high-dimensional optimization processes, and clustering-based niching. After giving an introduction to evolution strategies and machine learning, the book builds the bridge between both worlds with an algorithmic and experimental perspective. Experiments mostly employ a (1+1)-ES and are implemented in Python using the machine learning library scikit-learn. The examples are conducted on typical benchmark problems illustrating algorithmic concepts and their experimental behavior. The book closes with a discussion of related lines of research.

  15. Analysis of the Science and Technology Preservice Teachers' Opinions on Teaching Evolution and Theory of Evolution

    Science.gov (United States)

    Töman, Ufuk; Karatas, Faik Özgür; Çimer, Sabiha Odabasi

    2014-01-01

    In this study, we investigate of science and technology teachers' opinions about the theory of evolution and the evolution teaching. The aim of this study, we investigate of science and technology teachers' opinions about the theory of evolution and the evolution teaching. This study is a descriptive study. Open-ended questions were used to…

  16. Evolution of safeguards systems design

    International Nuclear Information System (INIS)

    Shipley, J.P.; Christensen, E.L.; Dietz, R.J.

    1979-01-01

    Safeguards systems play a vital detection and deterrence role in current nonproliferation policy. These safeguards systems have developed over the past three decades through the evolution of three essential components: the safeguards/process interface, safeguards performance criteria, and the technology necessary to support effective safeguards. This paper discusses the background and history of this evolutionary process, its major developments and status, and the future direction of safeguards system design

  17. Managing the evolution of cooperation

    OpenAIRE

    Dormann, Julian; Ehrmann, Thomas

    2008-01-01

    Management scholars have long stressed the importance of evolutionary processses for inter-firm cooperation but have mostly missed the promising opportunity to incorporate ideas from evolutionary theories into the analysis of collaborative arrangements. In this paper, we first present three rules for the evolution of cooperation - kinship selection, direct reciprocity, and indirect reciprocity. Second, we apply our theoretical considerations, enriched with ideas from cultural anthropology, to...

  18. INNOVATIONS AND TOURISTIC ACTIVITY EVOLUTION

    Directory of Open Access Journals (Sweden)

    V. S. Novikov

    2012-01-01

    Full Text Available Fundamental and applied innovations impact activities in the tourist industry and evolution thereof. More and more sophisticated technologies and communication techniques are practically used to serve tourists. Basically, innovative tourist activity development concept represents innovation of values and in particular means that tourist’s impression is taken into account to higher extent and tourist product personification changes the products’ consumer value. Discussed in the article are tourist activity, tourist cluster, destination and glocalization development prospects.

  19. Multiplicity in Early Stellar Evolution

    Science.gov (United States)

    Reipurth, B.; Clarke, C. J.; Boss, A. P.; Goodwin, S. P.; Rodríguez, L. F.; Stassun, K. G.; Tokovinin, A.; Zinnecker, H.

    Observations from optical to centimeter wavelengths have demonstrated that multiple systems of two or more bodies is the norm at all stellar evolutionary stages. Multiple systems are widely agreed to result from the collapse and fragmentation of cloud cores, despite the inhibiting influence of magnetic fields. Surveys of class 0 protostars with millimeter interferometers have revealed a very high multiplicity frequency of about 2/3, even though there are observational difficulties in resolving close protobinaries, thus supporting the possibility that all stars could be born in multiple systems. Near-infrared adaptive optics observations of class I protostars show a lower binary frequency relative to the class 0 phase, a declining trend that continues through the class II/III stages to the field population. This loss of companions is a natural consequence of dynamical interplay in small multiple systems, leading to ejection of members. We discuss observational consequences of this dynamical evolution, and its influence on circumstellar disks, and we review the evolution of circumbinary disks and their role in defining binary mass ratios. Special attention is paid to eclipsing PMS binaries, which allow for observational tests of evolutionary models of early stellar evolution. Many stars are born in clusters and small groups, and we discuss how interactions in dense stellar environments can significantly alter the distribution of binary separations through dissolution of wider binaries. The binaries and multiples we find in the field are the survivors of these internal and external destructive processes, and we provide a detailed overview of the multiplicity statistics of the field, which form a boundary condition for all models of binary evolution. Finally, we discuss various formation mechanisms for massive binaries, and the properties of massive trapezia.

  20. STATISTICAL ANALYSIS OF STELLAR EVOLUTION

    OpenAIRE

    van Dyk, DA; DeGennaro, S; Stein, N; Jefferys, WH; von Hippel, T

    2009-01-01

    Color-Magnitude Diagrams (CMDs) are plots that compare the magnitudes (luminosities) of stars in different wavelengths of light (colors). High nonlinear correlations among the mass, color, and surface temperature of newly formed stars induce a long narrow curved point cloud in a CMD known as the main sequence. Aging stars form new CMD groups of red giants and white dwarfs. The physical processes that govern this evolution can be described with mathematical models and explored using complex co...

  1. The evolution of military technology

    CERN Document Server

    Hagler, Gina

    2018-01-01

    War has at some point touched every nation. Beginning with ancient history and following through to the present, this book addresses the question of why war exists, and explains the shapes in which it occurs. It will lead young readers on a journey through time by tracing weapons from the earliest stones and clubs to modern technological military warfare. Along with the evolution of weaponry through the ages, it also goes into the development of protective gear, transportation, communication, and military strategies.

  2. Biological evolution: Some genetic considerations

    Directory of Open Access Journals (Sweden)

    Mohammad Saad Zaghloul Salem

    2014-01-01

    Conclusion: Natural selection might be observed in nature but not in life. The concept of biological evolution is an illogic and insensible hypothesis since it stands in direct contradiction with our current knowledge regarding the behavior as well as the structural and functional characteristics of the human genome and human proteome. Additionally, almost all basic postulations of this concept can neither be tested nor imitated for experimentation, which is a prerequisite for acceptance and validation of any scientific hypotheses.

  3. THE EVOLUTION OF MANAGERIAL ACCOUNTING

    OpenAIRE

    Delia MANEA

    2012-01-01

    The technological and organizational changes that have occurred in recent years, led to the apparition and then to continuous changes in managerial accounting, requiring the reconsideration of the existing informational system, so that it will contain all the information that managers need in order to make economic decisions. This paper aims to present the most important events that have marked the evolution of managerial accounting from its occurrence until today, and some courses of action ...

  4. The mystery of language evolution

    OpenAIRE

    Hauser, Marc D.; Yang, Charles; Berwick, Robert C.; Tattersall, Ian; Ryan, Michael J.; Watumull, Jeffrey; Chomsky, Noam; Lewontin, Richard C.

    2014-01-01

    Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, (1) studies of nonhuman animals prov...

  5. Dust evolution in protoplanetary disks

    OpenAIRE

    Gonzalez , Jean-François; Fouchet , Laure; T. Maddison , Sarah; Laibe , Guillaume

    2007-01-01

    6 pages, 5 figures, to appear in the Proceedings of IAU Symp. 249: Exoplanets: Detection, Formation and Dynamics (Suzhou, China); International audience; We investigate the behaviour of dust in protoplanetary disks under the action of gas drag using our 3D, two-fluid (gas+dust) SPH code. We present the evolution of the dust spatial distribution in global simulations of planetless disks as well as of disks containing an already formed planet. The resulting dust structures vary strongly with pa...

  6. Hominid evolution: genetics versus memetics

    Science.gov (United States)

    Carter, Brandon

    2012-01-01

    The last few million years on planet Earth have witnessed two remarkable phases of hominid development, starting with a phase of biological evolution characterized by rather rapid increase of the size of the brain. This has been followed by a phase of even more rapid technological evolution and concomitant expansion of the size of the population that began when our own particular ‘sapiens’ species emerged, just a few hundred thousand years ago. The present investigation exploits the analogy between the neo-Darwinian genetic evolution mechanism governing the first phase, and the memetic evolution mechanism governing the second phase. From the outset of the latter until very recently - about the year 2000 - the growth of the global population N was roughly governed by an equation of the form dN/Ndt=N/T*, in which T* is a coefficient introduced (in 1960) by von Foerster, who evaluated it empirically as about 200 000 million years. It is shown here how the value of this hitherto mysterious timescale governing the memetic phase is explicable in terms of what happened in the preceding genetic phase. The outcome is that the order of magnitude of the Foerster timescale can be accounted for as the product of the relevant (human) generation timescale, about 20 years, with the number of bits of information in the genome, of the order of 10 000 million. Whereas the origin of our ‘homo’ genus may well have involved an evolutionary hard step, it transpires that the emergence of our particular ‘sapiens’ species was rather an automatic process.

  7. The evolution of balanced scorecard

    OpenAIRE

    Eremina G.

    2016-01-01

    The article describes the evolution of the Balanced scorecard (BSC) as one of the world's most popular systems of measuring performance. The BSC, developed by Robert Kaplan and David Norton as a strategic management tool, has been constantly changing with the accumulation of practical experience of its use. The author of the article establishes the chronology of the publication of articles and books that have become milestones on the way of development of the BSC and traces of system changes ...

  8. Extended genomes: symbiosis and evolution

    OpenAIRE

    Hurst, Gregory D. D.

    2017-01-01

    Many aspects of an individual's biology derive from its interaction with symbiotic microbes, which further define many aspects of the ecology and evolution of the host species. The centrality of microbes in the function of individual organisms has given rise to the concept of the holobiont?that an individual's biology is best understood as a composite of the ?host organism? and symbionts within. This concept has been further elaborated to posit the holobiont as a unit of selection. In this re...

  9. The evolution of massive stars

    International Nuclear Information System (INIS)

    Loore, C. de

    1980-01-01

    The evolution of stars with masses between 15 M 0 and 100 M 0 is considered. Stars in this mass range lose a considerable fraction of their matter during their evolution. The treatment of convection, semi-convection and the influence of mass loss by stellar winds at different evolutionary phases are analysed as well as the adopted opacities. Evolutionary sequences computed by various groups are examined and compared with observations, and the advanced evolution of a 15 M 0 and a 25 M 0 star from zero-age main sequence (ZAMS) through iron collapse is discussed. The effect of centrifugal forces on stellar wind mass loss and the influence of rotation on evolutionary models is examined. As a consequence of the outflow of matter deeper layers show up and when the mass loss rates are large enough layers with changed composition, due to interior nuclear reactions, appear on the surface. The evolution of massive close binaries as well during the phase of mass loss by stellar wind as during the mass exchange and mass loss phase due to Roche lobe overflow is treated in detail, and the value of the parameters governing mass and angular momentum losses are discussed. The problem of the Wolf-Rayet stars, their origin and the possibilities of their production either as single stars or as massive binaries is examined. Finally, the origin of X-ray binaries is discussed and the scenario for the formation of these objects (starting from massive ZAMS close binaries, through Wolf-Rayet binaries leading to OB-stars with a compact companion after a supernova explosion) is reviewed and completed, including stellar wind mass loss. (orig.)

  10. Subchromosomal karyotype evolution in Equidae.

    Science.gov (United States)

    Musilova, P; Kubickova, S; Vahala, J; Rubes, J

    2013-04-01

    Equidae is a small family which comprises horses, African and Asiatic asses, and zebras. Despite equids having diverged quite recently, their karyotypes underwent rapid evolution which resulted in extensive differences among chromosome complements in respective species. Comparative mapping using whole-chromosome painting probes delineated genome-wide chromosome homologies among extant equids, enabling us to trace chromosome rearrangements that occurred during evolution. In the present study, we performed subchromosomal comparative mapping among seven Equidae species, representing the whole family. Region-specific painting and bacterial artificial chromosome probes were used to determine the orientation of evolutionarily conserved segments with respect to centromere positions. This allowed assessment of the configuration of all fusions occurring during the evolution of Equidae, as well as revealing discrepancies in centromere location caused by centromere repositioning or inversions. Our results indicate that the prevailing type of fusion in Equidae is centric fusion. Tandem fusions of the type telomere-telomere occur almost exclusively in the karyotype of Hartmann's zebra and are characteristic of this species' evolution. We revealed inversions in segments homologous to horse chromosomes 3p/10p and 13 in zebras and confirmed inversions in segments 4/31 in African ass, 7 in horse and 8p/20 in zebras. Furthermore, our mapping results suggested that centromere repositioning events occurred in segments homologous to horse chromosomes 7, 8q, 10p and 19 in the African ass and an element homologous to horse chromosome 16 in Asiatic asses. Centromere repositioning in chromosome 1 resulted in three different chromosome types occurring in extant species. Heterozygosity of the centromere position of this chromosome was observed in the kiang. Other subtle changes in centromere position were described in several evolutionary conserved chromosomal segments, suggesting that tiny

  11. Cosmic evolution, life and man

    International Nuclear Information System (INIS)

    Oro, J.

    1995-01-01

    Among the most basic problems confronting science are those regarding the origin of the universe, the origin of life and the origin of man. This general overview starts (1) with a brief introduction addressed primarily to the Cyril Ponnamperuma Memorial. Then, the thesis is presented that the appearance of life and intelligence on our planet can be understood as the result of a number of cosmic and biological evolutionary processes, including (2) the stellar thermonuclear synthesis of the biogenic elements other than hydrogen (C, N, O, P and S), their dispersal into space, and their combination into circumstellar and interstellar molecules. (3) The formation of the Solar System and the Earth-Moon System. (4) The role of comets and carbonaceous chondrites in contributing organic matter to the primitive Earth. (5) The prebiotics synthesis of amino acids, purines, pyrimidines, fatty acids, and other biochemical monomers. (6) The prebiotic condensation reactions leading to the synthesis of oligomers such as oligonucleotides and oligopeptides, with replicative and catalytic activities. (7) The synthesis of amphiphilic lipids, and their self-assembly into liposomes with bi-layered membranes. (8) The formation of protocellular structures. (9) The activation of protocells into a functioning Darwin's ancestral cell. (10) Early evolution of life. (11) The K-T boundary event and the disappearance of dinosaurs. (12) Evolution of hominids leading to Homo sapiens. (13) The rapid development of civilization. (14) The exploration of the Solar System. (15) Life beyond our planetary system. (16) Epilogue. Peace from cosmic evolution? (Abstract only)

  12. Landscape evolution by subglacial quarrying

    DEFF Research Database (Denmark)

    Ugelvig, Sofie Vej; Egholm, D.L.; Iverson, Neal R.

    In glacial landscape evolution models, subglacial erosion rates are often related to basal sliding or ice discharge by a power-law. This relation can be justified for bedrock abrasion because rock debris transported in the basal ice drives the erosion. However, a simple relation between rates of ...... evolution models. Geology, v. 40, no. 8, 679-682 (2012). Schoof, C. The effect of cavitation on glacier sliding. Proc. R. Soc. A , 461, 609-627 (2005). Jaeger, J.C., and Cook, N.G.W. Fundamentals of rock mechanics: New York, Chapman and Hall, 593 p. (1979)......In glacial landscape evolution models, subglacial erosion rates are often related to basal sliding or ice discharge by a power-law. This relation can be justified for bedrock abrasion because rock debris transported in the basal ice drives the erosion. However, a simple relation between rates...... of sliding and erosion is not well supported when considering models for quarrying of rock blocks from the bed. Iverson (2012) introduced a new subglacial quarrying model that operates from the theory of adhesive wear. The model is based on the fact that cavities, with a high level of bedrock differential...

  13. Evolution of democracy in Europe

    Science.gov (United States)

    Oberoi, Mukesh K.

    The emphasis of this thesis is to build an intuitive and robust GIS (Geographic Information systems) Tool which will give a survey on the evolution of democracy in European countries. The user can know about the evolution of the democratic histories of these countries by just clicking on them on the map. The information is provided in separate HTML pages which will give information about start of revolution, transition to democracy, current legislature, women's status in the country etc. There are two separate web pages for each country- one shows the detailed explanation on how democracy evolved in diff. countries and another page contains a timeline which holds key events of the evolution. The tool has been developed in JAVA. For the European map MOJO (Map Objects Java Objects) is used. MOJO is developed by ESRI. The major features shown on the European map were designed using MOJO. MOJO made it easy to incorporate the statistical data with these features. The user interface, as well as the language was intentionally kept simple and easy to use, to broaden the potential audience. To keep the user engaged, key aspects are explained using HTML pages. The idea is that users can view the timeline to get a quick overview and can go through the other html page to learn about things in more detail.

  14. The evolution of transmission mode

    Science.gov (United States)

    Forbes, Mark R.; Hauffe, Heidi C.; Kallio, Eva R.; Okamura, Beth; Sait, Steven M.

    2017-01-01

    This article reviews research on the evolutionary mechanisms leading to different transmission modes. Such modes are often under genetic control of the host or the pathogen, and often in conflict with each other via trade-offs. Transmission modes may vary among pathogen strains and among host populations. Evolutionary changes in transmission mode have been inferred through experimental and phylogenetic studies, including changes in transmission associated with host shifts and with evolution of the unusually complex life cycles of many parasites. Understanding the forces that determine the evolution of particular transmission modes presents a fascinating medley of problems for which there is a lack of good data and often a lack of conceptual understanding or appropriate methodologies. Our best information comes from studies that have been focused on the vertical versus horizontal transmission dichotomy. With other kinds of transitions, theoretical approaches combining epidemiology and population genetics are providing guidelines for determining when and how rapidly new transmission modes may evolve, but these are still in need of empirical investigation and application to particular cases. Obtaining such knowledge is a matter of urgency in relation to extant disease threats. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289251

  15. THE CHEMICAL EVOLUTION OF PHOSPHORUS

    International Nuclear Information System (INIS)

    Jacobson, Heather R.; Thanathibodee, Thanawuth; Frebel, Anna; Roederer, Ian U.; Cescutti, Gabriele; Matteucci, Francesca

    2014-01-01

    Phosphorus is one of the few remaining light elements for which little is known about its nucleosynthetic origin and chemical evolution, given the lack of optical absorption lines in the spectra of long-lived FGK-type stars. We have identified a P I doublet in the near-ultraviolet (2135/2136 Å) that is measurable in stars of low metallicity. Using archival Hubble Space Telescope-Space Telescope Imaging Spectrograph spectra, we have measured P abundances in 13 stars spanning –3.3 ≤ [Fe/H] ≤ -0.2, and obtained an upper limit for a star with [Fe/H] ∼ -3.8. Combined with the only other sample of P abundances in solar-type stars in the literature, which spans a range of –1 ≤ [Fe/H] ≤ +0.2, we compare the stellar data to chemical evolution models. Our results support previous indications that massive-star P yields may need to be increased by a factor of a few to match stellar data at all metallicities. Our results also show that hypernovae were important contributors to the P production in the early universe. As P is one of the key building blocks of life, we also discuss the chemical evolution of the important elements to life, C-N-O-P-S, together

  16. Stellar dynamics and galactic evolution

    International Nuclear Information System (INIS)

    Gilmore, G.; Kuijken, K.; Wyse, R.F.G.

    1989-01-01

    Solar neighbourhood observations have the unique capability of providing detailed study of the consequences of the early evolution of the Galaxy. Important examples of this capability include determination of the distribution of luminous and unseen mass in the Galaxy, and deduction of the rate of star formation and chemical evolution in the proto-Galaxy. We describe a new method to determine the distribution of mass in the Galactic disk. We reinvestigate determinations of the local volume mass density (the Oort limit) and show there to be serious internal inconsistencies in the available data. The most likely value for the local volume mass density, based on old stars and with kinematic models consistent with the age structure of the local disk is ∼ 0.1 solar mass pc -3 , though this value is still poorly determined. Thus, there is no significant evidence for any missing mass associated with the Galactic disk. We also reinvestigate observational data on the chemical abundances and kinematics of old stars in the Galaxy. The (Intermediate Population II) thick disk stars are most likely as old as the globular clusters, and kinematically distinct from the old disk. This favours models of thick disk origin involving a discrete disruptive event, such as the accretion of a satellite of the Galaxy early in the evolution of the Galactic disk. (author)

  17. Evolution caused by extreme events.

    Science.gov (United States)

    Grant, Peter R; Grant, B Rosemary; Huey, Raymond B; Johnson, Marc T J; Knoll, Andrew H; Schmitt, Johanna

    2017-06-19

    Extreme events can be a major driver of evolutionary change over geological and contemporary timescales. Outstanding examples are evolutionary diversification following mass extinctions caused by extreme volcanism or asteroid impact. The evolution of organisms in contemporary time is typically viewed as a gradual and incremental process that results from genetic change, environmental perturbation or both. However, contemporary environments occasionally experience strong perturbations such as heat waves, floods, hurricanes, droughts and pest outbreaks. These extreme events set up strong selection pressures on organisms, and are small-scale analogues of the dramatic changes documented in the fossil record. Because extreme events are rare, almost by definition, they are difficult to study. So far most attention has been given to their ecological rather than to their evolutionary consequences. We review several case studies of contemporary evolution in response to two types of extreme environmental perturbations, episodic (pulse) or prolonged (press). Evolution is most likely to occur when extreme events alter community composition. We encourage investigators to be prepared for evolutionary change in response to rare events during long-term field studies.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).

  18. Cosmic evolution, life and man

    Energy Technology Data Exchange (ETDEWEB)

    Oro, J [Houston Univ., Houston, TX (United States). Dept. of Biochemical and Biophysical Sciences

    1995-08-01

    Among the most basic problems confronting science are those regarding the origin of the universe, the origin of life and the origin of man. This general overview starts (1) with a brief introduction addressed primarily to the Cyril Ponnamperuma Memorial. Then, the thesis is presented that the appearance of life and intelligence on our planet can be understood as the result of a number of cosmic and biological evolutionary processes, including (2) the stellar thermonuclear synthesis of the biogenic elements other than hydrogen (C, N, O, P and S), their dispersal into space, and their combination into circumstellar and interstellar molecules. (3) The formation of the Solar System and the Earth-Moon System. (4) The role of comets and carbonaceous chondrites in contributing organic matter to the primitive Earth. (5) The prebiotics synthesis of amino acids, purines, pyrimidines, fatty acids, and other biochemical monomers. (6) The prebiotic condensation reactions leading to the synthesis of oligomers such as oligonucleotides and oligopeptides, with replicative and catalytic activities. (7) The synthesis of amphiphilic lipids, and their self-assembly into liposomes with bi-layered membranes. (8) The formation of protocellular structures. (9) The activation of protocells into a functioning Darwin`s ancestral cell. (10) Early evolution of life. (11) The K-T boundary event and the disappearance of dinosaurs. (12) Evolution of hominids leading to Homo sapiens. (13) The rapid development of civilization. (14) The exploration of the Solar System. (15) Life beyond our planetary system. (16) Epilogue. Peace from cosmic evolution? (Abstract only).

  19. Evolution Engines and Artificial Intelligence

    Science.gov (United States)

    Hemker, Andreas; Becks, Karl-Heinz

    In the last years artificial intelligence has achieved great successes, mainly in the field of expert systems and neural networks. Nevertheless the road to truly intelligent systems is still obscured. Artificial intelligence systems with a broad range of cognitive abilities are not within sight. The limited competence of such systems (brittleness) is identified as a consequence of the top-down design process. The evolution principle of nature on the other hand shows an alternative and elegant way to build intelligent systems. We propose to take an evolution engine as the driving force for the bottom-up development of knowledge bases and for the optimization of the problem-solving process. A novel data analysis system for the high energy physics experiment DELPHI at CERN shows the practical relevance of this idea. The system is able to reconstruct the physical processes after the collision of particles by making use of the underlying standard model of elementary particle physics. The evolution engine acts as a global controller of a population of inference engines working on the reconstruction task. By implementing the system on the Connection Machine (Model CM-2) we use the full advantage of the inherent parallelization potential of the evolutionary approach.

  20. Quantum Correlations Evolution Asymmetry in Quantum Channels

    International Nuclear Information System (INIS)

    Li Meng; Huang Yun-Feng; Guo Guang-Can

    2017-01-01

    It was demonstrated that the entanglement evolution of a specially designed quantum state in the bistochastic channel is asymmetric. In this work, we generalize the study of the quantum correlations, including entanglement and quantum discord, evolution asymmetry to various quantum channels. We found that the asymmetry of entanglement and quantum discord only occurs in some special quantum channels, and the behavior of the entanglement evolution may be quite different from the behavior of the quantum discord evolution. To quantum entanglement, in some channels it decreases monotonously with the increase of the quantum channel intensity. In some other channels, when we increase the intensity of the quantum channel, it decreases at first, then keeps zero for some time, and then rises up. To quantum discord, the evolution becomes more complex and you may find that it evolutes unsmoothly at some points. These results illustrate the strong dependence of the quantum correlations evolution on the property of the quantum channels. (paper)

  1. Evolution of the genus Aristolochia - Systematics, Molecular Evolution and Ecology

    OpenAIRE

    Wanke, Stefan

    2007-01-01

    Evolution of Piperales – matK gene and trnK intron sequence data reveal lineage specific resolution contrast. Piperales are one of the largest basal angiosperm orders with a nearly worldwide distribution. The order includes three species rich genera, Piper (ca. 1,000 species), Peperomia (ca. 1,500-1,700 species), and Aristolochia s. l. (ca. 500 species). Sequences of the matK gene and the non-coding trnK group II intron are analysed for a dense set of 105 taxa representing all families (excep...

  2. Dicty_cDB: SLE172 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available d/ 1126 0.0 VHJ195 (VHJ195Q) /CSM/VH/VHJ1-D/VHJ195Q.Seq.d/ 1102 0.0 SLD492 (SLD492Q) /CSM/SL/SLD4-D/SLD492... 0.0 1 ( AU052538 ) Dictyostelium discoideum slug cDNA, clone SLD492. 817 0.0 1 ( C83939 ) Dictyostelium dis

  3. Apoptosis of lymphocytes in SLE: the level, correlation with ...

    African Journals Online (AJOL)

    Lymphocytes were isolated from venous blood by method of gradient centrifugation of all the blood through a Ficoll-pak solution. The quantity apoptotic cells was determined in leukocytes by flow cytometry Epics XL-2 (“Beckman Coulter”, USA). Analysis of lymphocyte subpopulations was carried by using two fluorescent ...

  4. Dicty_cDB: SLE888 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available TAT TTATTTATS*i*sknifyqvslr**f****yqkmilkipffsl*fln*i*nk Translated Amino Acid sequence (All Frames) Frame A...TTATTAT TTATTTATS*i*sknifyqvslr**f****yqkmilkipffsl*fln*i*nk Homology vs CSM-cDNA Score E Sequences producin

  5. Dicty_cDB: SLE741 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available TATTTATTATTTATTTATS*i* sknifyqvslr**f****yqkmilkipffsl*fln*i*nk Translated Amino Acid sequence (All Frames) ...TTIA TTAATTTATTTATTATTTATTTATTTAATXXTTTAATTTATTTATTATTTATTTATS*i* sknifyqvslr**f****yqkmilkipffsl*fln*i*nk H

  6. Dicty_cDB: SLE686 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 016 |pid:none) Xenopus tropicalis methylcrotonoyl... 324 2e-87 CU633749_120( CU633749 |pid:none) Cupriavidus taiwan... 2e-87 CU633749_1505( CU633749 |pid:none) Cupriavidus taiwanensis str. LM... 323

  7. Clinical features of patients with systemic lupus erythematosus (SLE ...

    African Journals Online (AJOL)

    of this study was to determine the most common features of patients with systemic lupus erythematosus ... Conclusion: Most of the findings correlate with similar studies worldwide. .... Sciences, University of the Free State to conduct the study.

  8. Dicty_cDB: SLE427 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available PPERKYSVWIGGSILASLSTFQQMWISKEEYDESGPSIVHRKCF *immkvrqxxxiiii*q**ylnv**nlitfflmvvdlyptlkkkk*nq Translated Ami...ALAPSTMKIKIIAPPERKYSVWIGGSILASLSTFQQMWISKEEYDESGPSIVHRKCF *immkvrqxxxiiii*q**ylnv

  9. Dicty_cDB: SLE503 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available EPMDPVSEGIFDQYSVLKQV YRSSPVIASQLLLIDEIIKAGKGMRGSSVPEGQE*iyxxxiiiiiiik** Translated Amino Acid sequence (All ...VVPKTLAQNSGFDPMDTIIKLQEEYAKGHIVGLDVESGEPMDPVSEGIFDQYSVLKQV YRSSPVIASQLLLIDEIIKAGKGMRGSSVPEGQE*iyxxxii

  10. Generative inference for cultural evolution.

    Science.gov (United States)

    Kandler, Anne; Powell, Adam

    2018-04-05

    One of the major challenges in cultural evolution is to understand why and how various forms of social learning are used in human populations, both now and in the past. To date, much of the theoretical work on social learning has been done in isolation of data, and consequently many insights focus on revealing the learning processes or the distributions of cultural variants that are expected to have evolved in human populations. In population genetics, recent methodological advances have allowed a greater understanding of the explicit demographic and/or selection mechanisms that underlie observed allele frequency distributions across the globe, and their change through time. In particular, generative frameworks-often using coalescent-based simulation coupled with approximate Bayesian computation (ABC)-have provided robust inferences on the human past, with no reliance on a priori assumptions of equilibrium. Here, we demonstrate the applicability and utility of generative inference approaches to the field of cultural evolution. The framework advocated here uses observed population-level frequency data directly to establish the likely presence or absence of particular hypothesized learning strategies. In this context, we discuss the problem of equifinality and argue that, in the light of sparse cultural data and the multiplicity of possible social learning processes, the exclusion of those processes inconsistent with the observed data might be the most instructive outcome. Finally, we summarize the findings of generative inference approaches applied to a number of case studies.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'. © 2018 The Author(s).

  11. Evolution and convergence in telecommunications

    Energy Technology Data Exchange (ETDEWEB)

    Radicella, S; Grilli, D [Abdus Salam ICTP, Trieste (Italy)

    2002-12-15

    These lectures throw a spotlight on different aspects of the evolution of telecommunications networks, namely on the various facets of service and network convergence. The last years progress in data and telecommunications technologies, such as P-based networks, and the enormous potential of mobile communication systems and users' demands for comprehensive and network-independent have led to a convergence of data and telecommunications infrastructures in many aspects. In order to help the reader to an easier understanding of the phenomenon convergence, in the first two parts of this volume the evolution of the basic technologies is described one by one. This is done briefly and is focused on the principle topics, just to build a basis for the third part devoted to problems of convergence in telecommunications. These notes are addressed to those readers, who in a quick overview want to be informed on the future service and network landscape. The notes are equally suited for professionals with the desire to extend their horizon as well as for students looking for an introduction into telecommunications under more general aspects. The authors clearly understand the difficulties in writing a book devoted to the evolution in telecommunications. Today, telecom landscape varies at very high speed. Every few months new network technologies, new products and new services are developed. Attempts to present them in time can be accessible only for magazine publications or contributions to conferences. Therefore, in a number of areas, such as Voice over IP and new switching technologies not much more than the starting point of new paradigms is described. However, the content is up-to-date to a degree, that the phenomenon convergence can be fully understood. Partially, these notes are based on a number of lecture courses that were delivered during recent ICTP winter schools devoted to multimedia and digital communications.

  12. Massive Black Hole Binary Evolution

    Directory of Open Access Journals (Sweden)

    Merritt David

    2005-11-01

    Full Text Available Coalescence of binary supermassive black holes (SBHs would constitute the strongest sources of gravitational waves to be observed by LISA. While the formation of binary SBHs during galaxy mergers is almost inevitable, coalescence requires that the separation between binary components first drop by a few orders of magnitude, due presumably to interaction of the binary with stars and gas in a galactic nucleus. This article reviews the observational evidence for binary SBHs and discusses how they would evolve. No completely convincing case of a bound, binary SBH has yet been found, although a handful of systems (e.g. interacting galaxies; remnants of galaxy mergers are now believed to contain two SBHs at projected separations of <~ 1kpc. N-body studies of binary evolution in gas-free galaxies have reached large enough particle numbers to reproduce the slow, “diffusive” refilling of the binary’s loss cone that is believed to characterize binary evolution in real galactic nuclei. While some of the results of these simulations - e.g. the binary hardening rate and eccentricity evolution - are strongly N-dependent, others - e.g. the “damage” inflicted by the binary on the nucleus - are not. Luminous early-type galaxies often exhibit depleted cores with masses of ~ 1-2 times the mass of their nuclear SBHs, consistent with the predictions of the binary model. Studies of the interaction of massive binaries with gas are still in their infancy, although much progress is expected in the near future. Binary coalescence has a large influence on the spins of SBHs, even for mass ratios as extreme as 10:1, and evidence of spin-flips may have been observed.

  13. Circulating nucleic acids and evolution.

    Science.gov (United States)

    Anker, Philippe; Stroun, Maurice

    2012-06-01

    J.B. Lamarck in 1809 was the first to present a theory of evolution. He proposed it was due to the adaptation of species to environmental changes, this adaptation being acquired by the offspring. In 1868, Darwin suggested that cells excrete gemmules, which circulate through the body and reach the gonads where they are transmitted to the next generation. His main argument came from graft hybrids. In the fifties and sixties, Russian geneticists, rejecting neo-Darwinism, said that acquired characteristics were the basis of evolution. The main experiments on which they based their theory were the transmission of hereditary characteristics by a special technique of grafting between two varieties of plants. We repeated this kind of experiment and also succeeded in obtaining hereditary modifications of the pupil plants that acquired some characteristics of the mentor variety. Rather than adopting the views of the Russian scientists, we suggested that DNA was circulating between the mentor and pupil plants. Hirata's group have shown recently, by using molecular techniques such as cloning, RFLP PCR and sequencing some genes of their graft hybrids of pepper plants, that transfer of informative molecules from the mentor to the pupil plant does exist. Nucleic acids are actively released by cells; they circulate in the body. They can transform oncogenically or trigger antibody response but the only genetic transformation showing that DNA can go from the soma to the germen comes from graft hybrids. This suggests that circulating nucleic acids, in this case DNA, like Darwin's gemmules, play a role in the mechanism of evolution.

  14. The evolution of offensive realism.

    Science.gov (United States)

    Johnson, Dominic D P; Phil, D; Thayer, Bradley A

    Offensive realism, a theory of international relations, holds that states are disposed to competition and conflict because they are self-interested, power maximizing, and fearful of other states. Moreover, it argues that states are obliged to behave this way because doing so favors survival in the international system. Debate continues as to whether modern states actually do, or should, behave in this way, but we are struck by a different question. In this article, we ask whether the three core assumptions about behavior in offensive realism-self-help, power maximization, and outgroup fear-have any basis in scientific knowledge about human behavioral evolution. We find that these precise traits are not only evolutionarily adaptive but also empirically common across the animal kingdom, especially in primate and human societies. Based on these findings, we hypothesize that states behave as offensive realists predict not just because of anarchy in the modern international system but also because of the legacy of our evolution. In short, offensive realism may really be describing the nature of the human species more than the nature of the international system. If our hypothesis is correct, then evolutionary theory offers the following: (1) a novel ultimate cause of offensive realist behavior; (2) an extension of offensive realism to any domain in which humans compete for power; and (3) an explanation for why individual leaders themselves, and not just states, seek power. However, a key insight from evolution is that the primacy of self-help, power maximization, and outgroup fear does not necessarily condemn individuals or groups to competition and conflict; rather, these traits can in themselves give rise to cooperation and alliances.

  15. Evolution and convergence in telecommunications

    International Nuclear Information System (INIS)

    Radicella, S.; Grilli, D.

    2002-01-01

    These lectures throw a spotlight on different aspects of the evolution of telecommunications networks, namely on the various facets of service and network convergence. The last years progress in data and telecommunications technologies, such as P-based networks, and the enormous potential of mobile communication systems and users' demands for comprehensive and network-independent have led to a convergence of data and telecommunications infrastructures in many aspects. In order to help the reader to an easier understanding of the phenomenon convergence, in the first two parts of this volume the evolution of the basic technologies is described one by one. This is done briefly and is focused on the principle topics, just to build a basis for the third part devoted to problems of convergence in telecommunications. These notes are addressed to those readers, who in a quick overview want to be informed on the future service and network landscape. The notes are equally suited for professionals with the desire to extend their horizon as well as for students looking for an introduction into telecommunications under more general aspects. The authors clearly understand the difficulties in writing a book devoted to the evolution in telecommunications. Today, telecom landscape varies at very high speed. Every few months new network technologies, new products and new services are developed. Attempts to present them in time can be accessible only for magazine publications or contributions to conferences. Therefore, in a number of areas, such as Voice over IP and new switching technologies not much more than the starting point of new paradigms is described. However, the content is up-to-date to a degree, that the phenomenon convergence can be fully understood. Partially, these notes are based on a number of lecture courses that were delivered during recent ICTP winter schools devoted to multimedia and digital communications

  16. Crustal response to lithosphere evolution

    DEFF Research Database (Denmark)

    Artemieva, Irina; Thybo, Hans; Cherepanova, Yulia

    2012-01-01

    We present a new model for the structure of the crust in an area which stretches from the North Atlantic region in the west to the Verkhoyansk Ridge in the east and encompasses Greenland, Iceland, most of Europe, West Siberian basin, and the Siberian cratons. The model is based on critically asse......, thicknesses of different crustal layers, and Pn seismic velocities....... assessed results from various seismic studies, including reflection and refraction profiles and receiver function studies. The region includes a nearly continuous age record for crustal evolution over ca. 3.6-3.8 billion years. We present an analysis of the crustal structure heterogeneity in relation...

  17. Controlled quantum evolutions and transitions

    Energy Technology Data Exchange (ETDEWEB)

    Petroni, Nicola Cufaro [INFN Sezione di Bari, INFM Unitadi Bari and Dipartimento Interateneo di Fisica dell' Universitae del Politecnico di Bari, Bari (Italy); De Martino, Salvatore; De Siena, Silvio; Illuminati, Fabrizio [INFM Unitadi Salerno, INFN Sezione di Napoli - Gruppo collegato di Salerno and Dipartimento di Fisica dell' Universitadi Salerno, Baronissi, Salerno (Italy)

    1999-10-29

    We study the nonstationary solutions of Fokker-Planck equations associated to either stationary or non stationary quantum states. In particular, we discuss the stationary states of quantum systems with singular velocity fields. We introduce a technique that allows arbitrary evolutions ruled by these equations to account for controlled quantum transitions. As a first significant application we present a detailed treatment of the transition probabilities and of the controlling time-dependent potentials associated to the transitions between the stationary, the coherent, and the squeezed states of the harmonic oscillator. (author)

  18. Migration Process Evolution in Europe

    Directory of Open Access Journals (Sweden)

    Carmen Tudorache

    2006-08-01

    Full Text Available The migration phenomenon has always existed, fluctuating by the historic context, the economic, political, social and demographic disparities between the Central and East European countries and the EU Member States, the interdependencies between the origin and receiving countries and the European integration process evolutions. In the European Union, an integrated and inclusive approach of the migration issue is necessary. But a common policy on migration rests an ambitious objective. A common approach of the economic migration management and the harmonization of the migration policies of the Member States represented a challenge for the European Union and will become urgent in the future, especially due to the demographic ageing.

  19. The evolution of computer technology

    CERN Document Server

    Kamar, Haq

    2018-01-01

    Today it seems that computers occupy every single space in life. This book traces the evolution of computers from the humble beginnings as simple calculators up to the modern day jack-of-all trades devices like the iPhone. Readers will learn about how computers evolved from humongous military-issue refrigerators to the spiffy, delicate, and intriguing devices that many modern people feel they can't live without anymore. Readers will also discover the historical significance of computers, and their pivotal roles in World War II, the Space Race, and the emergence of modern Western powers.

  20. Evolution of Juvenile Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Ye.V. Prohorov

    2013-02-01

    Full Text Available Evolution of juvenile ankylosing spondylitis tend to follow a more frequent involvement in the pathological process of elbow and ankle joints, development of enthesiopathies, changes of intraarticular meniscal horns, forming of Baker’s cysts, cartilage flaps and systemic osteoporosis, and total value of all these signs 13 times exceeds thereof in patients with with the debut of disease in adulthood, but for juvenile ankylosing spondylitis vertebral lesion is less common. Age dimorphism of the use of certain groups of drugs and physiotherapy facilities is observed.

  1. Evolution of hybrid defect networks

    International Nuclear Information System (INIS)

    Martins, C. J. A. P.

    2009-01-01

    We apply a recently developed analytic model for the evolution of monopole networks to the case of monopoles attached to one string, usually known as hybrid networks. We discuss scaling solutions for both local and global hybrid networks, and also find an interesting application for the case of vortons. Our quantitative results agree with previous estimates in indicating that the hybrid networks will usually annihilate soon after the string-forming phase transition. However, we also show that in some specific circumstances these networks can survive considerably more than a Hubble time.

  2. Evolution of meaning special handbook

    CERN Document Server

    Wöhlbier, Fred H

    2014-01-01

    The Evolution of Meaning is based upon the premise that the Universe consists of information processing events. 'Information' is to be understood here not in the bare mathematical sense, but in the full active life/observation/meaning sense. From this viewpoint, the scientific description of Nature is seen to involve not only the fabric of spacetime, material aggregates and the forces acting between them, but also various equally real and fundamental groups of laws and law-like entities, as well as the concepts of subjectivity and value-oriented essential dimensi

  3. Brusque belt: a monocyclic evolution ?

    International Nuclear Information System (INIS)

    Basei, M.A.S.

    1990-01-01

    This paper discusses the radiometric data for the Brusque Belt (SC) where Rb-Sr isochrons, U-Pb in zircons, K-Ar in minerals and whole rock Sm-Nd model ages are available. The analysis of these results reveals two main groups, without intermediate values. The first, 500 to 800Ma., is related to magmatic and metamorphic ages and the second, 1600-2000Ma begin with the (probably) sedimentation age. A monociclic evolution is proposed, but with uncertanties in the age of the first metamorphic phase. (author)

  4. EVOLUTIONS IN GLOBAL AUTOMOBILES INDUSTRY

    OpenAIRE

    Viorel Pop

    2013-01-01

    This paper is a brief overview of the evolution of the global automotive industry during the 20th century, with reference to the main manufacturers, oil crises of 1970-1980, and also the global financial and economic crisis that began in 2008. The analyzed period covers the rise of the Asian Continent, beginning with Japan, then South Korea and more recently the emerging countries: China and India. What was predicted 20-25 years ago, became reality: Asia becomes the economic centre of the wor...

  5. Secular Evolution in Disk Galaxies

    Science.gov (United States)

    Kormendy, John

    2013-10-01

    Self-gravitating systems evolve toward the most tightly bound configuration that is reachable via the evolution processes that are available to them. They do this by spreading -- the inner parts shrink while the outer parts expand -- provided that some physical process efficiently transports energy or angular momentum outward. The reason is that self-gravitating systems have negative specific heats. As a result, the evolution of stars, star clusters, protostellar and protoplanetary disks, black hole accretion disks and galaxy disks are fundamentally similar. How evolution proceeds then depends on the evolution processes that are available to each kind of self-gravitating system. These processes and their consequences for galaxy disks are the subjects of my lectures and of this Canary Islands Winter School. I begin with a review of the formation, growth and death of bars. Then I review the slow (`secular') rearrangement of energy, angular momentum, and mass that results from interactions between stars or gas clouds and collective phenomena such as bars, oval disks, spiral structure and triaxial dark haloes. The `existence-proof' phase of this work is largely over: we have a good heuristic understanding of how nonaxisymmetric structures rearrange disk gas into outer rings, inner rings and stuff dumped onto the centre. The results of simulations correspond closely to the morphology of barred and oval galaxies. Gas that is transported to small radii reaches high densities. Observations confirm that many barred and oval galaxies have dense central concentrations of gas and star formation. The result is to grow, on timescales of a few Gyr, dense central components that are frequently mistaken for classical (elliptical-galaxy-like) bulges but that were grown slowly out of the disk (not made rapidly by major mergers). The resulting picture of secular galaxy evolution accounts for the richness observed in galaxy structure. We can distinguish between classical and pseudo

  6. Evolution as a collective phenomenon

    International Nuclear Information System (INIS)

    Chela-Flores, J.

    1984-10-01

    The quantum mechanical description of biosystems, which emphasizes their dielectric properties and the presence of an uncorrelated condensate of phonons (in analogy with Bose-Einstein condensation), is extended to a description of biosystems, in which the condensed phonons show anomalous averages (in analogy with superconductivity). The theory is used to show that a quantum ultraviolet defense mechanism may have been present at the origin of chemical evolution, removing a difficulty in the standard scenario. Suggestions are made as to how to proceed experimentally to show the existence of a correlated phonon condensate. (author)

  7. Launching "the evolution of cooperation".

    Science.gov (United States)

    Axelrod, Robert

    2012-04-21

    This article describes three aspects of the author's early work on the evolution of the cooperation. First, it explains how the idea for a computer tournament for the iterated Prisoner's Dilemma was inspired by the artificial intelligence research on computer checkers and computer chess. Second, it shows how the vulnerability of simple reciprocity of misunderstanding or misimplementation can be eliminated with the addition of some degree of generosity or contrition. Third, it recounts the unusual collaboration between the author, a political scientist, and William D. Hamilton, an evolutionary biologist. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Evolution of collectivity in nuclei

    International Nuclear Information System (INIS)

    Muralithar, S.

    2016-01-01

    Nuclear structure studies provide opportunity to understand various modes of excitations and shapes of nucleus as a function of angular momentum, excitation energy and iso-spin. Single particle and collective excitations keep competing and give rise to interesting structures. Phenomena namely back bending, band termination, shape co-existence, rotational bands with different configurations and octupole correlation were reported using gamma ray spectroscopy method. Above nuclear phenomena were studied using Gamma detector array (GDA), Plunger, Heavy Ion Recoil Analyser GDA, Indian National Gamma Array - HlRA at IUAC by various users. Some examples of evolution of collectivity in nuclear structure studies carried out will be presented. (author)

  9. On the evolution of stars

    International Nuclear Information System (INIS)

    Kippenhahn, R.

    1989-01-01

    A popular survey is given of the present knowledge on evolution and ageing of stars. Main sequence stars, white dwarf stars, and red giant stars are classified in the Hertzsprung-Russell (HR)-diagram by measurable quantities: surface temperature and luminosity. From the HR-diagram it can be concluded to star mass and age. Star-forming processes in interstellar clouds as well as stellar burning processes are illustrated. The changes occurring in a star due to the depletion of the nuclear energy reserve are described. In this frame the phenomena of planetary nebulae, supernovae, pulsars, neutron stars as well as of black holes are explained

  10. The Criticism of Atheistic Evolution

    Directory of Open Access Journals (Sweden)

    Farah Ramin

    2010-03-01

    Full Text Available With regard to close relation between evolution theory and religious knowledge, and its prodigious influence on arising new schools in philosophy this paper firstly considers the outcome of Darwin’s theologian theory in brief secondly it talks about recent controversies such as: ambiguity of Fitness concept, tautology and the usage of probability calculation in this theory,opposition of the second law of thermodynamics (Entropy, biological information in DNA, irreducible complexity, Fine-tuning of decisive nature constant and Anthropic Principle .

  11. Archeology and evolution of QCD

    CERN Document Server

    De Rújula, A.

    2017-01-01

    These are excerpts from the closing talk at the "XIIth Conference on Quark Confinement and the Hadron Spectrum", which took place last Summer in Thessaloniki --an excellent place to enjoy an interest in archeology. A more complete personal view of the early days of QCD and the rest of the Standard Model is given in [1]. Here I discuss a few of the points which --to my judgement-- illustrate well the QCD evolution (in time), both from a scientific and a sociological point of view.

  12. A comparison of biological and cultural evolution.

    Science.gov (United States)

    Portin, Petter

    2015-03-01

    This review begins with a definition of biological evolution and a description of its general principles. This is followed by a presentation of the biological basis of culture, specifically the concept of social selection. Further, conditions for cultural evolution are proposed, including a suggestion for language being the cultural replicator corresponding to the concept of the gene in biological evolution. Principles of cultural evolution are put forward and compared to the principles of biological evolution. Special emphasis is laid on the principle of selection in cultural evolution, including presentation of the concept of cultural fitness. The importance of language as a necessary condition for cultural evolution is stressed. Subsequently, prime differences between biological and cultural evolution are presented, followed by a discussion on interaction of our genome and our culture. The review aims at contributing to the present discussion concerning the modern development of the general theory of evolution, for example by giving a tentative formulation of the necessary and sufficient conditions for cultural evolution, and proposing that human creativity and mind reading or theory of mind are motors specific for it. The paper ends with the notion of the still ongoing coevolution of genes and culture.

  13. THE PSEUDO-EVOLUTION OF HALO MASS

    International Nuclear Information System (INIS)

    Diemer, Benedikt; Kravtsov, Andrey V.; More, Surhud

    2013-01-01

    A dark matter halo is commonly defined as a spherical overdensity of matter with respect to a reference density, such as the critical density or the mean matter density of the universe. Such definitions can lead to a spurious pseudo-evolution of halo mass simply due to redshift evolution of the reference density, even if its physical density profile remains constant over time. We estimate the amount of such pseudo-evolution of mass between z = 1 and 0 for halos identified in a large N-body simulation, and show that it accounts for almost the entire mass evolution of the majority of halos with M 200ρ-bar ≲ 10 12 h -1 M ☉ and can be a significant fraction of the apparent mass growth even for cluster-sized halos. We estimate the magnitude of the pseudo-evolution assuming that halo density profiles remain static in physical coordinates, and show that this simple model predicts the pseudo-evolution of halos identified in numerical simulations to good accuracy, albeit with significant scatter. We discuss the impact of pseudo-evolution on the evolution of the halo mass function and show that the non-evolution of the low-mass end of the halo mass function is the result of a fortuitous cancellation between pseudo-evolution and the absorption of small halos into larger hosts. We also show that the evolution of the low-mass end of the concentration-mass relation observed in simulations is almost entirely due to the pseudo-evolution of mass. Finally, we discuss the implications of our results for the interpretation of the evolution of various scaling relations between the observable properties of galaxies and galaxy clusters and their halo masses.

  14. Molecular outflows in protostellar evolution

    International Nuclear Information System (INIS)

    Fukui, Y.; Iwata, T.; Mizuno, A.; Ogawa, H.; Kawabata, K.; Sugitani, K.

    1989-01-01

    Molecular outflow is an energetic mass-ejection phenomenon associated with very early stage of stellar evolution. The large kinetic energy involved in the phenomenon indicates that outflow may play an essential role in the process of star formation, particularly by extracting angular momentum. Most of the previous searches have been strongly biased toward optical or near-infrared signposts of star formation. They are not able, therefore, to provide the complete database necessary for a statistical study of the evolutionary status of molecular outflow. To overcome this difficulty, it is of vital importance to make an unbiased search of single molecular clouds for molecular outflows; here we report the final result of such a survey of the Lynds 1641 dark cloud. We show that molecular outflows are characterized by a total luminosity significantly greater than that of T Tauri stars. This indicates that molecular outflow corresponds to the main accretion phase of protostellar evolution, in which the luminosity excess is due to the gravitational energy released by dynamical mass accretion onto the protostellar core. (author)

  15. Evolution, plant breeding and biodiversity

    Directory of Open Access Journals (Sweden)

    Salvatore Ceccarelli

    2011-11-01

    Full Text Available This paper deals with changes in biodiversity during the course of evolution, plant domestication and plant breeding. It shows than man has had a strong influence on the progressive decrease of biodiversity, unconscious at first and deliberate in modern times. The decrease in biodiversity in the agricultures of the North causes a severe threat to food security and is in contrasts with the conservation of biodiversity which is part of the culture of several populations in the South. The concluding section of the paper shows that man could have guided evolution in a different way and shows an example of participatory plant breeding, a type of breeding which is done in collaboration with farmers and is based on selection for specific adaptation. Even though participatory plant breeding has been practiced for only about 20 years and by relatively few groups, the effects on both biodiversity and crop production are impressive. Eventually the paper shows how participatory plant breeding can be developed into ‘evolutionary plant breeding’ to cope in a dynamic way with climate changes.

  16. The mystery of language evolution

    Directory of Open Access Journals (Sweden)

    Marc D Hauser

    2014-05-01

    Full Text Available Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, 1 studies of nonhuman animals provide virtually no relevant parallels to human linguistic communication, and none to the underlying biological capacity; 2 the fossil and archaeological evidence does not inform our understanding of the computations and representations of our earliest ancestors, leaving details of origins and selective pressure unresolved; 3 our understanding of the genetics of language is so impoverished that there is little hope of connecting genes to linguistic processes any time soon; 4 all modeling attempts have made unfounded assumptions, and have provided no empirical tests, thus leaving any insights into language’s origins unverifiable. Based on the current state of evidence, we submit that the most fundamental questions about the origins and evolution of our linguistic capacity remain as mysterious as ever, with considerable uncertainty about the discovery of either relevant or conclusive evidence that can adjudicate among the many open hypotheses. We conclude by presenting some suggestions about possible paths forward.

  17. The mystery of language evolution

    Science.gov (United States)

    Hauser, Marc D.; Yang, Charles; Berwick, Robert C.; Tattersall, Ian; Ryan, Michael J.; Watumull, Jeffrey; Chomsky, Noam; Lewontin, Richard C.

    2014-01-01

    Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, (1) studies of nonhuman animals provide virtually no relevant parallels to human linguistic communication, and none to the underlying biological capacity; (2) the fossil and archaeological evidence does not inform our understanding of the computations and representations of our earliest ancestors, leaving details of origins and selective pressure unresolved; (3) our understanding of the genetics of language is so impoverished that there is little hope of connecting genes to linguistic processes any time soon; (4) all modeling attempts have made unfounded assumptions, and have provided no empirical tests, thus leaving any insights into language's origins unverifiable. Based on the current state of evidence, we submit that the most fundamental questions about the origins and evolution of our linguistic capacity remain as mysterious as ever, with considerable uncertainty about the discovery of either relevant or conclusive evidence that can adjudicate among the many open hypotheses. We conclude by presenting some suggestions about possible paths forward. PMID:24847300

  18. Evolution of Karyotypes in Chameleons

    Directory of Open Access Journals (Sweden)

    Michail Rovatsos

    2017-12-01

    Full Text Available The reconstruction of the evolutionary dynamics of karyotypes and sex determining systems in squamate reptiles is precluded by the lack of data in many groups including most chameleons (Squamata: Acrodonta: Chamaeleonidae. We performed cytogenetic analysis in 16 species of chameleons from 8 genera covering the phylogenetic diversity of the family and also phylogenetic reconstruction of karyotype evolution in this group. In comparison to other squamates, chameleons demonstrate rather variable karyotypes, differing in chromosome number, morphology and presence of interstitial telomeric signal (ITS. On the other hand, the location of rDNA is quite conserved among chameleon species. Phylogenetic analysis combining our new results and previously published data tentatively suggests that the ancestral chromosome number for chameleons is 2n = 36, which is the same as assumed for other lineages of the clade Iguania, i.e., agamids and iguanas. In general, we observed a tendency for the reduction of chromosome number during the evolution of chameleons, however, in Rieppeleon brevicaudatus, we uncovered a chromosome number of 2n = 62, very unusual among squamates, originating from a number of chromosome splits. Despite the presence of the highly differentiated ZZ/ZW sex chromosomes in the genus Furcifer, we did not detect any unequivocal sexual differences in the karyotypes of any other studied species of chameleons tested using differential staining and comparative genomic hybridization, suggesting that sex chromosomes in most chameleons are only poorly differentiated.

  19. The mystery of language evolution.

    Science.gov (United States)

    Hauser, Marc D; Yang, Charles; Berwick, Robert C; Tattersall, Ian; Ryan, Michael J; Watumull, Jeffrey; Chomsky, Noam; Lewontin, Richard C

    2014-01-01

    Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, (1) studies of nonhuman animals provide virtually no relevant parallels to human linguistic communication, and none to the underlying biological capacity; (2) the fossil and archaeological evidence does not inform our understanding of the computations and representations of our earliest ancestors, leaving details of origins and selective pressure unresolved; (3) our understanding of the genetics of language is so impoverished that there is little hope of connecting genes to linguistic processes any time soon; (4) all modeling attempts have made unfounded assumptions, and have provided no empirical tests, thus leaving any insights into language's origins unverifiable. Based on the current state of evidence, we submit that the most fundamental questions about the origins and evolution of our linguistic capacity remain as mysterious as ever, with considerable uncertainty about the discovery of either relevant or conclusive evidence that can adjudicate among the many open hypotheses. We conclude by presenting some suggestions about possible paths forward.

  20. The Chemical Evolution of Phosphorus

    Science.gov (United States)

    Jacobson, Heather R.; Thanathibodee, Thanawuth; Frebel, Anna; Roederer, Ian U.; Cescutti, Gabriele; Matteucci, Francesca

    2014-12-01

    Phosphorus is one of the few remaining light elements for which little is known about its nucleosynthetic origin and chemical evolution, given the lack of optical absorption lines in the spectra of long-lived FGK-type stars. We have identified a P I doublet in the near-ultraviolet (2135/2136 Å) that is measurable in stars of low metallicity. Using archival Hubble Space Telescope-Space Telescope Imaging Spectrograph spectra, we have measured P abundances in 13 stars spanning -3.3 production in the early universe. As P is one of the key building blocks of life, we also discuss the chemical evolution of the important elements to life, C-N-O-P-S, together. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. This work is supported through program AR-13246. Other portions of this work are based on data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile, and the McDonald Observatory of the University of Texas at Austin.

  1. Controlling Tensegrity Robots Through Evolution

    Science.gov (United States)

    Iscen, Atil; Agogino, Adrian; SunSpiral, Vytas; Tumer, Kagan

    2013-01-01

    Tensegrity structures (built from interconnected rods and cables) have the potential to offer a revolutionary new robotic design that is light-weight, energy-efficient, robust to failures, capable of unique modes of locomotion, impact tolerant, and compliant (reducing damage between the robot and its environment). Unfortunately robots built from tensegrity structures are difficult to control with traditional methods due to their oscillatory nature, nonlinear coupling between components and overall complexity. Fortunately this formidable control challenge can be overcome through the use of evolutionary algorithms. In this paper we show that evolutionary algorithms can be used to efficiently control a ball-shaped tensegrity robot. Experimental results performed with a variety of evolutionary algorithms in a detailed soft-body physics simulator show that a centralized evolutionary algorithm performs 400 percent better than a hand-coded solution, while the multi-agent evolution performs 800 percent better. In addition, evolution is able to discover diverse control solutions (both crawling and rolling) that are robust against structural failures and can be adapted to a wide range of energy and actuation constraints. These successful controls will form the basis for building high-performance tensegrity robots in the near future.

  2. Modeling SOL evolution during disruptions

    International Nuclear Information System (INIS)

    Rognlien, T.D.; Cohen, R.H.; Crotinger, J.A.

    1996-01-01

    We present the status of our models and transport simulations of the 2-D evolution of the scrape-off layer (SOL) during tokamak disruptions. This evolution is important for several reasons: It determines how the power from the core plasma is distributed on material surfaces, how impurities from those surfaces or from gas injection migrate back to the core region, and what are the properties of the SOL for carrying halo currents. We simulate this plasma in a time-dependent fashion using the SOL transport code UEDGE. This code models the SOL plasma using fluid equations of plasma density, parallel momentum (along the magnetic field), electron energy, ion energy, and neutral gas density. A multispecies model is used to follow the density of different charge-states of impurities. The parallel transport is classical but with kinetic modifications; these are presently treated by flux limits, but we have initiated more sophisticated models giving the correct long-mean-free path limit. The cross-field transport is anomalous, and one of the results of this work is to determine reasonable values to characterize disruptions. Our primary focus is on the initial thermal quench phase when most of the core energy is lost, but the total current is maintained. The impact of edge currents on the MHD equilibrium will be discussed

  3. Evolution of solar ultraviolet luminosity

    International Nuclear Information System (INIS)

    Zahnle, K.J.; Walker, J.C.G.

    1982-01-01

    In view of the major role of the sun in defining the properties of planetary atmospheres, their evolution cannot be fully understood outside the context of an evolving sun. The ultraviolet radiation is especially interesting because of its strong interaction with planetary atmospheres. We use astronomical observation of stars that are analogous to the sun in order to reconstruct a tentative account of the evolution of solar UV luminosity. A wealth of evidence indicates that the young sun was a much more powerful source of energetic particles and radiation than it is today. While on the main sequence, solar activity has declined as an inverse power law of age (between t -5 and t/sup -1.2/) as a consequence of angular momentum loss to the solar wind. Recent IUE satellite observations of premain sequence stars suggest that before the sun reached the main sequence (at an age of about 50 m.y.), it may have emitted as much as 10 4 times as much ultraviolet radiation (γ<2000 A) than it does today. These results could impact our understanding of the photochemistry and escape of constituents of primordial planetary atmospheres

  4. Dynamical Evolution of Ring-Satellite Systems

    Science.gov (United States)

    Ohtsuki, Keiji

    2005-01-01

    The goal of this research was to understand dynamical processes related to the evolution of size distribution of particles in planetary rings and application of theoretical results to explain features in the present rings of giant planets. We studied velocity evolution and accretion rates of ring particles in the Roche zone. We developed a new numerical code for the evolution of ring particle size distribution, which takes into account the above results for particle velocity evolution and accretion rates. We also studied radial diffusion rate of ring particles due to inelastic collisions and gravitational encounters. Many of these results can be also applied to dynamical evolution of a planetesimal disk. Finally, we studied rotation rates of moonlets and particles in planetary rings, which would influence the accretional evolution of these bodies. We describe our key accomplishments during the past three years in more detail in the following.

  5. Evolution algebras generated by Gibbs measures

    International Nuclear Information System (INIS)

    Rozikov, Utkir A.; Tian, Jianjun Paul

    2009-03-01

    In this article we study algebraic structures of function spaces defined by graphs and state spaces equipped with Gibbs measures by associating evolution algebras. We give a constructive description of associating evolution algebras to the function spaces (cell spaces) defined by graphs and state spaces and Gibbs measure μ. For finite graphs we find some evolution subalgebras and other useful properties of the algebras. We obtain a structure theorem for evolution algebras when graphs are finite and connected. We prove that for a fixed finite graph, the function spaces have a unique algebraic structure since all evolution algebras are isomorphic to each other for whichever Gibbs measures are assigned. When graphs are infinite graphs then our construction allows a natural introduction of thermodynamics in studying of several systems of biology, physics and mathematics by theory of evolution algebras. (author)

  6. A Python Calculator for Supernova Remnant Evolution

    Science.gov (United States)

    Leahy, D. A.; Williams, J. E.

    2017-05-01

    A freely available Python code for modeling supernova remnant (SNR) evolution has been created. This software is intended for two purposes: to understand SNR evolution and to use in modeling observations of SNR for obtaining good estimates of SNR properties. It includes all phases for the standard path of evolution for spherically symmetric SNRs. In addition, alternate evolutionary models are available, including evolution in a cloudy ISM, the fractional energy-loss model, and evolution in a hot low-density ISM. The graphical interface takes in various parameters and produces outputs such as shock radius and velocity versus time, as well as SNR surface brightness profile and spectrum. Some interesting properties of SNR evolution are demonstrated using the program.

  7. Lifetime monogamy and the evolution of eusociality

    DEFF Research Database (Denmark)

    Boomsma, Jacobus J

    2009-01-01

    and termites is thus analogous to the evolution of multicellularity. Focusing on lifetime monogamy as a universal precondition for the evolution of obligate eusociality simplifies the theory and may help to resolve controversies about levels of selection and targets of adaptation. The monogamy window...... underlines that cooperative breeding and eusociality are different domains of social evolution, characterized by different sectors of parameter space for Hamilton's rule....

  8. Dilation of non-quasifree dissipative evolution

    Energy Technology Data Exchange (ETDEWEB)

    Varilly, J C [Costa Rica Univ., San Jose. Escuela de Matematica

    1981-03-01

    A semigroup evolution for the 1/2-spin which admits a conservative dilation is known to be governed by a Bloch equation in a standard form. Here we construct a conservative dilation directly from the Bloch equation, thus yielding an example of a dilation scheme for an evolution which is not quasifree. Moreover, we show that this conservative evolution is never ergodic in the non-quasifree case.

  9. Evolution of supernova remnants. III. Thermal waves

    International Nuclear Information System (INIS)

    Chevalier, R.A.

    1975-01-01

    The effect of heat conduction on the evolution of supernova remnants is investigated. A thermal wave, or electron conduction front, can travel more rapidly than a shock wave during the first thousand years of the remnant's evolution. A self-similar solution describing this phase has been found by Barenblatt. Numerical computations verify the solution and give the evolution past the thermal wave phase. While shell formation is not impeded, the interior density and temperature profiles are smoothed by the action of conduction

  10. Enhancer evolution across 20 mammalian species

    DEFF Research Database (Denmark)

    Villar, Diego; Berthelot, Camille; Aldridge, Sarah

    2015-01-01

    The mammalian radiation has corresponded with rapid changes in noncoding regions of the genome, but we lack a comprehensive understanding of regulatory evolution in mammals. Here, we track the evolution of promoters and enhancers active in liver across 20 mammalian species from six diverse orders...... by profiling genomic enrichment of H3K27 acetylation and H3K4 trimethylation. We report that rapid evolution of enhancers is a universal feature of mammalian genomes. Most of the recently evolved enhancers arise from ancestral DNA exaptation, rather than lineage-specific expansions of repeat elements....... These results provide important insight into the functional genetics underpinning mammalian regulatory evolution....

  11. Correlations and discreteness in nonlinear QCD evolution

    International Nuclear Information System (INIS)

    Armesto, N.; Milhano, J.

    2006-01-01

    We consider modifications of the standard nonlinear QCD evolution in an attempt to account for some of the missing ingredients discussed recently, such as correlations, discreteness in gluon emission and Pomeron loops. The evolution is numerically performed using the Balitsky-Kovchegov equation on individual configurations defined by a given initial value of the saturation scale, for reduced rapidities y=(α s N c /π)Y<10. We consider the effects of averaging over configurations as a way to implement correlations, using three types of Gaussian averaging around a mean saturation scale. Further, we heuristically mimic discreteness in gluon emission by considering a modified evolution in which the tails of the gluon distributions are cut off. The approach to scaling and the behavior of the saturation scale with rapidity in these modified evolutions are studied and compared with the standard mean-field results. For the large but finite values of rapidity explored, no strong quantitative difference in scaling for transverse momenta around the saturation scale is observed. At larger transverse momenta, the influence of the modifications in the evolution seems most noticeable in the first steps of the evolution. No influence on the rapidity behavior of the saturation scale due to the averaging procedure is found. In the cutoff evolution the rapidity evolution of the saturation scale is slowed down and strongly depends on the value of the cutoff. Our results stress the need to go beyond simple modifications of evolution by developing proper theoretical tools that implement such recently discussed ingredients

  12. Statistical dynamics of religion evolutions

    Science.gov (United States)

    Ausloos, M.; Petroni, F.

    2009-10-01

    A religion affiliation can be considered as a “degree of freedom” of an agent on the human genre network. A brief review is given on the state of the art in data analysis and modelization of religious “questions” in order to suggest and if possible initiate further research, after using a “statistical physics filter”. We present a discussion of the evolution of 18 so-called religions, as measured through their number of adherents between 1900 and 2000. Some emphasis is made on a few cases presenting a minimum or a maximum in the investigated time range-thereby suggesting a competitive ingredient to be considered, besides the well accepted “at birth” attachment effect. The importance of the “external field” is still stressed through an Avrami late stage crystal growth-like parameter. The observed features and some intuitive interpretations point to opinion based models with vector, rather than scalar, like agents.

  13. Evolution of the indoor biome.

    Science.gov (United States)

    Martin, Laura J; Adams, Rachel I; Bateman, Ashley; Bik, Holly M; Hawks, John; Hird, Sarah M; Hughes, David; Kembel, Steven W; Kinney, Kerry; Kolokotronis, Sergios-Orestis; Levy, Gabriel; McClain, Craig; Meadow, James F; Medina, Raul F; Mhuireach, Gwynne; Moreau, Corrie S; Munshi-South, Jason; Nichols, Lauren M; Palmer, Clare; Popova, Laura; Schal, Coby; Täubel, Martin; Trautwein, Michelle; Ugalde, Juan A; Dunn, Robert R

    2015-04-01

    Few biologists have studied the evolutionary processes at work in indoor environments. Yet indoor environments comprise approximately 0.5% of ice-free land area--an area as large as the subtropical coniferous forest biome. Here we review the emerging subfield of 'indoor biome' studies. After defining the indoor biome and tracing its deep history, we discuss some of its evolutionary dimensions. We restrict our examples to the species found in human houses--a subset of the environments constituting the indoor biome--and offer preliminary hypotheses to advance the study of indoor evolution. Studies of the indoor biome are situated at the intersection of evolutionary ecology, anthropology, architecture, and human ecology and are well suited for citizen science projects, public outreach, and large-scale international collaborations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. The evolution of homo touristicus

    Directory of Open Access Journals (Sweden)

    Duccio Canestrini

    2016-09-01

    Full Text Available This article looks at the evolution of homo touristicus, a concept that originally referred to a person with a decent level of income who travelled for pleasure for short periods of time, taking advantage of the geoeconomic disparity between their habitual residence and the destinations chosen. This category has grown to include new sub-species and varieties that take in a wide range of forms and motivations and goes far beyond the old ways of being a tourist. These days, tourism is constructed according to new tastes and new technologies; it seems genetically modified and as such it promotes itself and consumes. Although there is still a generic demand for escape, the settings have changed. This paper sets out some of these changes, goes on to note the particular obsession with the safety of the tourist and, finally, appeals for a harmonious development of tourist activity.

  15. Historical Contingency in Controlled Evolution

    Science.gov (United States)

    Schuster, Peter

    2014-12-01

    A basic question in evolution is dealing with the nature of an evolutionary memory. At thermodynamic equilibrium, at stable stationary states or other stable attractors the memory on the path leading to the long-time solution is erased, at least in part. Similar arguments hold for unique optima. Optimality in biology is discussed on the basis of microbial metabolism. Biology, on the other hand, is characterized by historical contingency, which has recently become accessible to experimental test in bacterial populations evolving under controlled conditions. Computer simulations give additional insight into the nature of the evolutionary memory, which is ultimately caused by the enormous space of possibilities that is so large that it escapes all attempts of visualization. In essence, this contribution is dealing with two questions of current evolutionary theory: (i) Are organisms operating at optimal performance? and (ii) How is the evolutionary memory built up in populations?

  16. Galapagos: Darwin, evolution, and ENT.

    Science.gov (United States)

    Bluestone, Charles D

    2009-10-01

    This year is especially important in the history of the theory of evolution; 2009 is the bicentennial anniversary of the birth of Charles Darwin and the sesquicentennial anniversary of his publication, The Origin of Species. Darwin visited the Galapagos Islands as a young man, which greatly influenced his thinking. My son Jim and I had the good fortune to visit these islands in January 2009 and see firsthand what led Darwin to arrive at his monumental insights into the origins of life on this planet. I have described my observations and related some of this experience to the ear, nose, and throat, albeit with whimsy in several instances. Nonetheless, some of the adaptations in the animals on these unique islands may have bearing on my hypotheses related to the incidence and pathogenesis of otitis media in humans. It is hoped the reader will share my enthusiasm for the experience we had on these fantastic islands and tour them in the future.

  17. Viral diseases and human evolution

    Directory of Open Access Journals (Sweden)

    Leal Élcio de Souza

    2000-01-01

    Full Text Available The interaction of man with viral agents was possibly a key factor shaping human evolution, culture and civilization from its outset. Evidence of the effect of disease, since the early stages of human speciation, through pre-historical times to the present suggest that the types of viruses associated with man changed in time. As human populations progressed technologically, they grew in numbers and density. As a consequence different viruses found suitable conditions to thrive and establish long-lasting associations with man. Although not all viral agents cause disease and some may in fact be considered beneficial, the present situation of overpopulation, poverty and ecological inbalance may have devastating effets on human progress. Recently emerged diseases causing massive pandemics (eg., HIV-1 and HCV, dengue, etc. are becoming formidable challenges, which may have a direct impact on the fate of our species.

  18. INFORMATION SOCIETY EVOLUTION AND EFFECTS

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2016-01-01

    The evolution and effects of the information society can be exemplified via many threads, both in hard and soft science, according to ones’ discipline and field. In this contribution, the speaker’s three decades of applied research acts as a vehicle to demonstrate development and impact via...... commercial product, national and international projects, and industry startups (including impactful third party research investigations) form the basis for discussion. Beyond this, a wider more generic perspective reflects on product adoption that illustrate todays’ contemporary e-society tendencies where...... recent influx and uptake of consumer-targeted artificial reality products point to society’s desire for alternative sensory experiences. Posited is how aligned with this desire there is a need for new ethical considerations in research as was found in the speaker’s research at the end of the 20th century...

  19. The Gradual Evolution of Language

    Directory of Open Access Journals (Sweden)

    Michael C. Corballis

    2014-12-01

    Full Text Available Language is commonly held to be unique to humans, and to have emerged suddenly in a single “great leap forward” within the past 100,000 years. The view is profoundly anti-Darwinian, and I propose instead a framework for understanding how language might have evolved incrementally from our primate heritage. One major proposition is that language evolved from manual action, with vocalization emerging as the dominant mode late in hominin evolution. The second proposition has to do with the role of language as a means of communicating about events displaced in space and time from the present. Some have argued that mental time travel itself is unique to human, which might explain why language itself is uniquely human. I argue instead that mental time travel has ancient evolutionary origins, and gradually assumed narrative-like properties during the Pleistocene, when language itself began to take shape.

  20. Quantum evolution by discrete measurements

    International Nuclear Information System (INIS)

    Roa, L; Guevara, M L Ladron de; Delgado, A; Olivares-RenterIa, G; Klimov, A B

    2007-01-01

    In this article we review two ways of driving a quantum system to a known pure state via a sequence discrete of von Neumann measurements. The first of them assumes that the initial state of the system is unknown, and the evolution is attained only with the help of two non-commuting observables. For this method, the overall success probability is maximized when the eigentstates of the involved observables constitute mutually unbiased bases. The second method assumes the initial state is known and it uses N observables which are consecutively measured to make the state of the system approach the target state. The probability of success of this procedure converges to 1 as the number of observables increases