WorldWideScience

Sample records for non-markovian effects manifest

  1. Non-Markovianity during quantum Zeno effect

    CERN Document Server

    Thilagam, A

    2013-01-01

    We examine the Zeno and anti-Zeno effects in the context of non-Markovian dynamics in entangled spin-boson systems in contact with noninteracting reservoirs. We identify enhanced non-Markovian signatures in specific two-qubit partitions of a Bell-like initial state, with results showing that the intra-qubit Zeno effect or anti-Zeno effect occurs in conjunction with inter-qubit non-Markovian dynamics for a range of system parameters. The time domain of effective Zeno or anti-Zeno dynamics is about the same order of magnitude as the non-Markovian time scale of the reservoir correlation dynamics, and changes in decay rate due to the Zeno mechanism appears coordinated with information flow between specific two-qubit partitions. We extend our analysis to examine the Zeno mechanism-non-Markovianity link using the tripartite states arising from a donor-acceptor-sink model of photosynthetic biosystems.

  2. Effect of memory in non-Markovian Boolean networks

    CERN Document Server

    Ebadi, Haleh; Ausloos, Marcel; Jafari, GholamReza

    2016-01-01

    One successful model of interacting biological systems is the Boolean network. The dynamics of a Boolean network, controlled with Boolean functions, is usually considered to be a Markovian (memory-less) process. However, both self organizing features of biological phenomena and their intelligent nature should raise some doubt about ignoring the history of their time evolution. Here, we extend the Boolean network Markovian approach: we involve the effect of memory on the dynamics. This can be explored by modifying Boolean functions into non-Markovian functions, for example, by investigating the usual non-Markovian threshold function, - one of the most applied Boolean functions. By applying the non-Markovian threshold function on the dynamical process of a cell cycle network, we discover a power law memory with a more robust dynamics than the Markovian dynamics.

  3. Noise spectrum of quantum transport through double quantum dots: Renormalization and non-Markovian effects

    Directory of Open Access Journals (Sweden)

    Pengqin Shi

    2016-09-01

    Full Text Available Based on the time-nonlocal particle number-resolved master equation, we investigate the sequential electron transport through the interacting double quantum dots. Our calculations show that there exists the effect of energy renormalization in the dispersion of the bath interaction spectrum and it is sensitive to the the bandwidth of the bath. This effect would strongly affect the stationary current and its zero-frequency shot noise for weak inter-dot coherent coupling strength, but for strong inter-dot coupling regime, it is negligible due to the strong intrinsic Rabi coherent dynamics. Moreover, the possible observable effects of the energy renormalization in the noise spectrum are also investigated through the Rabi coherence signal. Finally, the non-Markovian effect is manifested in the finite-frequency noise spectrum with the appearance of quasisteps, and the magnitude of these quasisteps are modified by the dispersion function.

  4. Noise spectrum of quantum transport through double quantum dots: Renormalization and non-Markovian effects

    Science.gov (United States)

    Shi, Pengqin; Hu, Menghan; Ying, Yaofeng; Jin, Jinshuang

    2016-09-01

    Based on the time-nonlocal particle number-resolved master equation, we investigate the sequential electron transport through the interacting double quantum dots. Our calculations show that there exists the effect of energy renormalization in the dispersion of the bath interaction spectrum and it is sensitive to the the bandwidth of the bath. This effect would strongly affect the stationary current and its zero-frequency shot noise for weak inter-dot coherent coupling strength, but for strong inter-dot coupling regime, it is negligible due to the strong intrinsic Rabi coherent dynamics. Moreover, the possible observable effects of the energy renormalization in the noise spectrum are also investigated through the Rabi coherence signal. Finally, the non-Markovian effect is manifested in the finite-frequency noise spectrum with the appearance of quasisteps, and the magnitude of these quasisteps are modified by the dispersion function.

  5. Non-markovian effects in semiconductor cavity QED: Role of phonon-mediated processes

    DEFF Research Database (Denmark)

    Nielsen, Per Kær; Nielsen, Torben Roland; Lodahl, Peter;

    We show theoretically that the non-Markovian nature of the carrier-phonon interaction influences the dynamical properties of a semiconductor cavity QED system considerably, leading to asymmetries with respect to detuning in carrier lifetimes. This pronounced phonon effect originates from the pola......We show theoretically that the non-Markovian nature of the carrier-phonon interaction influences the dynamical properties of a semiconductor cavity QED system considerably, leading to asymmetries with respect to detuning in carrier lifetimes. This pronounced phonon effect originates from...

  6. Non-Markovian effect on the geometric phase of a dissipative qubit

    CERN Document Server

    Chen, Juan-Juan; Tong, Qing-Jun; Luo, Hong-Gang; Oh, C H

    2010-01-01

    We study the geometric phase of a two-level atom coupled to an environment with Lorentzian spectral density. The non-Markovian effect on the geometric phase is explored analytically and numerically. In the weak coupling limit the lowest-order correction to the geometric phase is derived analytically and the general case is calculated numerically. It is found that the correction to the geometric phase is significantly large if the spectral width is small and in this case the non-Markovian dynamics has a significant impact to the geometric phase. When the spectral width increases, the correction to the geometric phase becomes negligible, which shows the robustness of the geometric phase to the environmental white noises. The result is significant to the quantum information processing based on the geometric phase.

  7. Effect of memory in non-Markovian Boolean networks illustrated with a case study: A cell cycling process

    Science.gov (United States)

    Ebadi, H.; Saeedian, M.; Ausloos, M.; Jafari, G. R.

    2016-11-01

    The Boolean network is one successful model to investigate discrete complex systems such as the gene interacting phenomenon. The dynamics of a Boolean network, controlled with Boolean functions, is usually considered to be a Markovian (memory-less) process. However, both self-organizing features of biological phenomena and their intelligent nature should raise some doubt about ignoring the history of their time evolution. Here, we extend the Boolean network Markovian approach: we involve the effect of memory on the dynamics. This can be explored by modifying Boolean functions into non-Markovian functions, for example, by investigating the usual non-Markovian threshold function —one of the most applied Boolean functions. By applying the non-Markovian threshold function on the dynamical process of the yeast cell cycle network, we discover a power-law-like memory with a more robust dynamics than the Markovian dynamics.

  8. Non-Markovian property of afterpulsing effect in single-photon avalanche detector

    CERN Document Server

    Wang, Fang-Xiang; Li, Ya-Ping; He, De-Yong; Wang, Chao; Han, Yun-Guang; Wang, Shuang; Yin, Zhen-Qiang; Han, Zheng-Fu

    2016-01-01

    The single-photon avalanche photodiode(SPAD) has been widely used in research on quantum optics. The afterpulsing effect, which is an intrinsic character of SPAD, affects the system performance in most experiments and needs to be carefully handled. For a long time, afterpulsing has been presumed to be determined by the pre-ignition avalanche. We studied the afterpulsing effect of a commercial InGaAs/InP SPAD (The avalanche photodiode model is: Princeton Lightwave PGA-300) and demonstrated that its afterpulsing is non-Markovian, with a memory effect in the avalanching history. Theoretical analysis and experimental results clearly indicate that the embodiment of this memory effect is the afterpulsing probability, which increases as the number of ignition-avalanche pulses increase. This conclusion makes the principle of the afterpulsing effect clearer and is instructive to the manufacturing processes and afterpulsing evaluation of high-count-rate SPADs. It can also be regarded as a fundamental premise to handle ...

  9. Qubit Decoherence and Non-Markovian Dynamics at Low Temperatures via an Effective Spin-Boson Model

    CERN Document Server

    Shiokawa, K

    2004-01-01

    Quantum Brownian oscillator model (QBM), in the Fock-space representation, can be viewed as a multi-level spin-boson model. At sufficiently low temperature, the oscillator degrees of freedom are dynamically reduced to the lowest two levels and the system behaves effectively as a two-level (E2L) spin-boson model (SBM) in this limit. We discuss the physical mechanism of level reduction and analyze the behavior of E2L-SBM from the QBM solutions. The availability of close solutions for the QBM enables us to study the non-Markovian features of decoherence and leakage in a SBM in the non-perturbative regime (e.g. without invoking the Born approximation) in better details than before. Our result captures very well the characteristic non-Markovian short time low temperature behavior common in many models.

  10. Non-Markovian dynamical effects and time evolution of entanglement entropy of a dissipative two-state system

    CERN Document Server

    Lü, Zhiguo

    2011-01-01

    We investigate the dynamical information exchange between a two-state system and its environment which is measured by von Neumann entropy. It is found that in the underdamping regime, the entropy dynamics exhibits an extremely non-Markovian oscillation-hump feature, in which oscillations manifest quantum coherence and a hump of envelop demonstrates temporal memory of bath. It indicates that the process of entropy exchange is bidirectional. When the coupling strength increases a certain threshold, the hump along with ripple disappears, which is indicative of the coherent-incoherent dynamical crossover. The long-time limit of entropy evolution reaches the ground state value which agrees with that of numerical renormalization group.

  11. Excitation energy transfer efficiency: equivalence of transient and stationary setting and the absence of non-Markovian effects

    CERN Document Server

    Jesenko, Simon

    2013-01-01

    We analyze efficiency of excitation energy transfer in photosynthetic complexes in transient and stationary setting. In the transient setting the absorption process is modeled as an individual event resulting in a subsequent relaxation dynamics. In the stationary setting the absorption is a continuous stationary process, leading to the nonequilibrium steady state. We show that, as far as the efficiency is concerned, both settings can be considered to be the same, as they result in almost identical efficiency. We also show that non-Markovianity has no effect on the resulting efficiency, i.e., corresponding Markovian dynamics results in identical efficiency. Even more, if one maps dynamics to appropriate classical rate equations, the same efficiency as in quantum case is obtained.

  12. Long-time memory in non-Markovian evolutions

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej; Pascazio, Saverio

    2010-03-01

    If the dynamics of an open quantum system is non-Markovian, its asymptotic state strongly depends on the initial conditions, even if the dynamics possesses an invariant state. This is the very essence of memory effects. In particular, the asymptotic state can remember and partially preserve its initial entanglement. Interestingly, even if the non-Markovian evolution relaxes to an equilibrium state, this state needs not be invariant. Therefore, the noninvariance of equilibrium becomes a clear sign of non-Markovianity.

  13. Non-Markovian dynamics for bipartite systems

    OpenAIRE

    2008-01-01

    We analyze the appearance of non-Markovian effects in the dynamics of a bipartite system coupled to a reservoir, which can be described within a class of non-Markovian equations given by a generalized Lindblad structure. A novel master equation, which we term quantum Bloch-Boltzmann equation, is derived, describing both motional and internal states of a test particle in a quantum framework. When due to the preparation of the system or to decoherence effects one of the two degrees of freedom i...

  14. Elephants can always remember: Exact long-range memory effects in a non-Markovian random walk

    Science.gov (United States)

    Schütz, Gunter M.; Trimper, Steffen

    2004-10-01

    We consider a discrete-time random walk where the random increment at time step t depends on the full history of the process. We calculate exactly the mean and variance of the position and discuss its dependence on the initial condition and on the memory parameter p . At a critical value pc(1)=1/2 where memory effects vanish there is a transition from a weakly localized regime [where the walker (elephant) returns to its starting point] to an escape regime. Inside the escape regime there is a second critical value where the random walk becomes superdiffusive. The probability distribution is shown to be governed by a non-Markovian Fokker-Planck equation with hopping rates that depend both on time and on the starting position of the walk. On large scales the memory organizes itself into an effective harmonic oscillator potential for the random walker with a time-dependent spring constant k=(2p-1)/t . The solution of this problem is a Gaussian distribution with time-dependent mean and variance which both depend on the initiation of the process.

  15. Witnessing non-Markovianity of quantum evolution

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej

    2014-01-01

    We provide further characterization of non-Markovian quantum dynamics based on the concept of divisible dynamical maps. In analogy to entanglement witness we propose a non-Markovianity witness and introduce the corresponding measure of non-Markovianity. We also provide characterization of non-Markovianity in terms of Wigner-Yanase-Dyson skew information.

  16. Non-Markovian reduced dynamics based upon a hierarchical effective-mode representation

    Energy Technology Data Exchange (ETDEWEB)

    Burghardt, Irene [Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt (Germany); Martinazzo, Rocco [Dipartimento di Chimica, Universita degli Studi di Milano, v. Golgi 19, 20133 Milano (Italy); Hughes, Keith H. [School of Chemistry, Bangor University, Bangor, Gwynedd LL57 2UW (United Kingdom)

    2012-10-14

    A reduced dynamics representation is introduced which is tailored to a hierarchical, Mori-chain type representation of a bath of harmonic oscillators which are linearly coupled to a subsystem. We consider a spin-boson system where a single effective mode is constructed so as to absorb all system-environment interactions, while the residual bath modes are coupled bilinearly to the primary mode and among each other. Using a cumulant expansion of the memory kernel, correlation functions for the primary mode are obtained, which can be suitably approximated by truncated chains representing the primary-residual mode interactions. A series of reduced-dimensional bath correlation functions is thus obtained, which can be expressed as Fourier-Laplace transforms of spectral densities that are given in truncated continued-fraction form. For a master equation which is second order in the system-bath coupling, the memory kernel is re-expressed in terms of local-in-time equations involving auxiliary densities and auxiliary operators.

  17. Non-Markovian Reactivation of Quantum Relays

    CERN Document Server

    Pirandola, Stefano; Jacobsen, Christian S; Spedalieri, Gaetana; Braunstein, Samuel L; Gehring, Tobias; Andersen, Ulrik L

    2015-01-01

    We consider a quantum relay which is used by two parties to perform several continuous-variable protocols: Entanglement swapping, distillation, quantum teleportation, and quantum key distribution. The theory of these protocols is extended to a non-Markovian model of decoherence characterized by correlated Gaussian noise. Even if bipartite entanglement is completely lost at the relay, we show that the various protocols can progressively be reactivated by the separable noise-correlations of the environment. In fact, above a critical amount, these correlations are able to restore the distribution of quadripartite entanglement, which can be localized into an exploitable bipartite form by the action of the relay. Our findings are confirmed by a proof-of-principle experiment and show the potential advantages of non-Markovian effects in a quantum network architecture.

  18. Quantum non-Markovianity: characterization, quantification and detection.

    Science.gov (United States)

    Rivas, Ángel; Huelga, Susana F; Plenio, Martin B

    2014-09-01

    We present a comprehensive and up-to-date review of the concept of quantum non-Markovianity, a central theme in the theory of open quantum systems. We introduce the concept of a quantum Markovian process as a generalization of the classical definition of Markovianity via the so-called divisibility property and relate this notion to the intuitive idea that links non-Markovianity with the persistence of memory effects. A detailed comparison with other definitions presented in the literature is provided. We then discuss several existing proposals to quantify the degree of non-Markovianity of quantum dynamics and to witness non-Markovian behavior, the latter providing sufficient conditions to detect deviations from strict Markovianity. Finally, we conclude by enumerating some timely open problems in the field and provide an outlook on possible research directions.

  19. A Simple Non-Markovian Computational Model of the Statistics of Soccer Leagues: Emergence and Scaling effects

    CERN Document Server

    da Silva, Roberto; Lamb, Luis; Prado, Sandra

    2012-01-01

    We propose a novel algorithm that outputs the final standings of a soccer league, based on a simple dynamics that mimics a soccer tournament. In our model, a team is created with a defined potential(ability) which is updated during the tournament according to the results of previous games. The updated potential modifies a teams' future winning/losing probabilities. We show that this evolutionary game is able to reproduce the statistical properties of final standings of actual editions of the Brazilian tournament (Brasileir\\~{a}o). However, other leagues such as the Italian and the Spanish tournaments have notoriously non-Gaussian traces and cannot be straightforwardly reproduced by this evolutionary non-Markovian model. A complete understanding of these phenomena deserves much more attention, but we suggest a simple explanation based on data collected in Brazil: Here several teams were crowned champion in previous editions corroborating that the champion typically emerges from random fluctuations that partly ...

  20. Non-Gaussian fluctuations and non-Markovian effects in the nuclear fusion process: Langevin dynamics emerging from quantum molecular dynamics simulations.

    Science.gov (United States)

    Wen, Kai; Sakata, Fumihiko; Li, Zhu-Xia; Wu, Xi-Zhen; Zhang, Ying-Xun; Zhou, Shan-Gui

    2013-07-05

    Macroscopic parameters as well as precise information on the random force characterizing the Langevin-type description of the nuclear fusion process around the Coulomb barrier are extracted from the microscopic dynamics of individual nucleons by exploiting the numerical simulation of the improved quantum molecular dynamics. It turns out that the dissipation dynamics of the relative motion between two fusing nuclei is caused by a non-Gaussian distribution of the random force. We find that the friction coefficient as well as the time correlation function of the random force takes particularly large values in a region a little bit inside of the Coulomb barrier. A clear non-Markovian effect is observed in the time correlation function of the random force. It is further shown that an emergent dynamics of the fusion process can be described by the generalized Langevin equation with memory effects by appropriately incorporating the microscopic information of individual nucleons through the random force and its time correlation function.

  1. Non-Markovianity-assisted steady state entanglement.

    Science.gov (United States)

    Huelga, Susana F; Rivas, Ángel; Plenio, Martin B

    2012-04-20

    We analyze the steady state entanglement generated in a coherently coupled dimer system subject to dephasing noise as a function of the degree of Markovianity of the evolution. By keeping fixed the effective noise strength while varying the memory time of the environment, we demonstrate that non-Markovianity is an essential, quantifiable resource that may support the formation of steady state entanglement whereas purely Markovian dynamics governed by Lindblad master equations lead to separable steady states. This result illustrates possible mechanisms leading to long-lived entanglement in purely decohering, possibly local, environments. We present a feasible experimental demonstration of this noise assisted phenomenon using a system of trapped ions.

  2. Non-Markovianity hinders Quantum Darwinism

    Science.gov (United States)

    Galve, Fernando; Zambrini, Roberta; Maniscalco, Sabrina

    2016-01-01

    We investigate Quantum Darwinism and the emergence of a classical world from the quantum one in connection with the spectral properties of the environment. We use a microscopic model of quantum environment in which, by changing a simple system parameter, we can modify the information back flow from environment into the system, and therefore its non-Markovian character. We show that the presence of memory effects hinders the emergence of classical objective reality, linking these two apparently unrelated concepts via a unique dynamical feature related to decoherence factors.

  3. Non-Markovian Diffusive Unravellings of Entanglement

    CERN Document Server

    Corn, Brittany; Yu, Ting

    2011-01-01

    The fully quantized model of two qubits coupled to a common bath is solved using the quantum state diffusion (QSD) approach in the non-Markovian regime. We have established an explicit time-local non-Markovian QSD equation for the two-qubit dissipative model. Diffusive quantum trajectories are applied to the entanglement estimation of two-qubit systems in a non-Markovian regime. In another interesting example, we have also considered exact entanglement unravellings for a dephasing model. In both cases, non-Markovian features of entanglement evolution are revealed through quantum diffusive unravellings in the qubit state space.

  4. A simple non-Markovian computational model of the statistics of soccer leagues: Emergence and scaling effects

    Science.gov (United States)

    da Silva, Roberto; Vainstein, Mendeli H.; Lamb, Luis C.; Prado, Sandra D.

    2013-03-01

    We propose a novel probabilistic model that outputs the final standings of a soccer league, based on a simple dynamics that mimics a soccer tournament. In our model, a team is created with a defined potential (ability) which is updated during the tournament according to the results of previous games. The updated potential modifies a team future winning/losing probabilities. We show that this evolutionary game is able to reproduce the statistical properties of final standings of actual editions of the Brazilian tournament (Brasileirão) if the starting potential is the same for all teams. Other leagues such as the Italian (Calcio) and the Spanish (La Liga) tournaments have notoriously non-Gaussian traces and cannot be straightforwardly reproduced by this evolutionary non-Markovian model with simple initial conditions. However, we show that by setting the initial abilities based on data from previous tournaments, our model is able to capture the stylized statistical features of double round robin system (DRRS) tournaments in general. A complete understanding of these phenomena deserves much more attention, but we suggest a simple explanation based on data collected in Brazil: here several teams have been crowned champion in previous editions corroborating that the champion typically emerges from random fluctuations that partly preserve the Gaussian traces during the tournament. On the other hand, in the Italian and Spanish cases, only a few teams in recent history have won their league tournaments. These leagues are based on more robust and hierarchical structures established even before the beginning of the tournament. For the sake of completeness, we also elaborate a totally Gaussian model (which equalizes the winning, drawing, and losing probabilities) and we show that the scores of the Brazilian tournament “Brasileirão” cannot be reproduced. This shows that the evolutionary aspects are not superfluous and play an important role which must be considered in

  5. Decoherence of Josephson charge qubit in non-Markovian environment

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Qing-Qian; Zhou, Xing-Fei; Liang, Xian-Ting, E-mail: liangxianting@nbu.edu.cn

    2016-05-15

    In this paper we investigate the decoherence of Josephson charge qubit (JCQ) by using a time-nonlocal (TNL) dynamical method. Three kinds of environmental models, described with Ohmic, super-Ohmic, and sub-Ohmic spectral density functions are considered. It is shown that the TNL method can effectively include the non-Markovian effects in the dynamical solutions. In particular, it is shown that the sub-Ohmic environment has longer correlation time than the Ohmic and super-Ohmic ones. And the Markovian and non-Markovian dynamics are obviously different for the qubit in sub-Ohmic environment.

  6. Programmable entanglement oscillations in a non Markovian channel

    CERN Document Server

    Cialdi, Simone; Tesio, Enrico; Paris, Matteo G A

    2010-01-01

    We suggest and demonstrate an all-optical experimental setup to observe and engineer entanglement oscillations of a pair of polarization qubits in a non-Markovian channel. We generate entangled photon pairs by spontaneous parametric downconversion (SPDC), and then insert a programmable spatial light modulator in order to impose a polarization dependent phase-shift on the spatial domain of the SPDC output and to create an effective non-Markovian environment. Modulation of the enviroment spectrum is obtained by inserting a spatial grating on the signal arm. In our experiment, programmable oscillations of entanglement are achieved, with the maximally revived state that violates Bell's inequality by 17 standard deviations.

  7. Long-time memory in non-Markovian evolutions

    CERN Document Server

    Chruściński, Dariusz; Pascazio, Saverio

    2009-01-01

    If the dynamics of an open quantum systems is non-Markovian, its asymptotic state strongly depends on the initial conditions, even if the dynamics possesses an invariant state. This is the very essence of memory effects. In particular, the asymptotic state can remember and partially preserve its initial entanglement.

  8. Non-Markovian time evolution of an accelerated qubit

    CERN Document Server

    Moustos, Dimitris

    2016-01-01

    We present a new method for evaluating the response of a moving qubit detector interacting with a scalar field in Minkowski spacetime. We treat the detector as an open quantum system, but we do not invoke the Markov approximation. The evolution equations for the qubit density matrix are valid at all times, for all qubit trajectories and they incorporate non-Markovian effects. We analyze in detail the case of uniform acceleration, providing a detailed characterization of all regimes where non-Markovian effects are significant. We argue that the most stable characterization of acceleration temperature refers to the late time behavior of the detector, because interaction with the field vacuum brings the qubit to a thermal state at the Unruh temperature. In contrast, the early-time transition rate, that is invoked in most discussions of acceleration temperature, does not exhibit a thermal behavior when non-Markovian effects are taken into account. Finally, we note that the non-Markovian evolution derived here als...

  9. Non-Markovian character in human mobility: Online and offline

    Science.gov (United States)

    Zhao, Zhi-Dan; Cai, Shi-Min; Lu, Yang

    2015-06-01

    The dynamics of human mobility characterizes the trajectories that humans follow during their daily activities and is the foundation of processes from epidemic spreading to traffic prediction and information recommendation. In this paper, we investigate a massive data set of human activity, including both online behavior of browsing websites and offline one of visiting towers based mobile terminations. The non-Markovian character observed from both online and offline cases is suggested by the scaling law in the distribution of dwelling time at individual and collective levels, respectively. Furthermore, we argue that the lower entropy and higher predictability in human mobility for both online and offline cases may originate from this non-Markovian character. However, the distributions of individual entropy and predictability show the different degrees of non-Markovian character between online and offline cases. To account for non-Markovian character in human mobility, we apply a protype model with three basic ingredients, namely, preferential return, inertial effect, and exploration to reproduce the dynamic process of online and offline human mobilities. The simulations show that the model has an ability to obtain characters much closer to empirical observations.

  10. Entanglement and non-Markovianity of a multi-level atom decaying in a cavity

    Science.gov (United States)

    Zi-Long, Fan; Yu-Kun, Ren; Hao-Sheng, Zeng

    2016-01-01

    We present a paradigmatic method for exactly studying non-Markovian dynamics of a multi-level V-type atom interacting with a zero-temperature bosonic bath. Special attention is paid to the entanglement evolution and the dynamical non-Markovianity of a three-level V-type atom. We find that the entanglement negativity decays faster and non-Markovianity is smaller in the resonance regions than those in the non-resonance regions. More importantly, the quantum interference between the dynamical non-Markovianities induced by different transition channels is manifested, and the frequency domains for constructive and destructive interferences are found. Project supported by the National Natural Science Foundation of China (Grant Nos. 11275064 and 11075050), the Specialized Research Fund for the Doctoral Program of Higher Education, China (Grant No. 20124306110003), and the Construct Program of the National Key Discipline, China.

  11. Non-Markovian Dynamics for a Two-Atom-Coupled System Interacting with Local Reservoir at Finite Temperature

    Science.gov (United States)

    Jiang, Li; Zhang, Guo-Feng

    2017-03-01

    By using the effective non-Markovian measure (Breuer et al., Phys. Rev. Lett. 103, 210401 2009) we investigate non-Markovian dynamics of a pair of two-level atoms (TLAs) system, each of which interacting with a local reservoir. We show that subsystem dynamics can be controlled by manipulating the coupling between TLAs, temperature and relaxation rate of the atoms. Moreover, the correlation between non-Markovianity of subsystem and entanglement between the subsystem and the structured bath is investigated, the results show that the emergence of non-Markovianity has a negative effect on the entanglement.

  12. Non-Markovianity Measure Based on Brukner–Zeilinger Invariant Information for Unital Quantum Dynamical Maps

    Science.gov (United States)

    He, Zhi; Zhu, Lie-Qiang; Li, Li

    2017-03-01

    A non-Markovianity measure based on Brukner–Zeilinger invariant information to characterize non-Markovian effect of open systems undergoing unital dynamical maps is proposed. The method takes advantage of non-increasing property of the Brukner–Zeilinger invariant information under completely positive and trace-preserving unital maps. The simplicity of computing the Brukner–Zeilinger invariant information is the advantage of the proposed measure because of mainly depending on the purity of quantum state. The measure effectively captures the characteristics of non-Markovianity of unital dynamical maps. As some concrete application, we consider two typical non-Markovian noise channels, i.e., the phase damping channel and the random unitary channel to show the sensitivity of the proposed measure. By investigation, we find that the conditions of detecting the non-Markovianity for the phase damping channel are consistent with the results of existing measures for non-Markovianity, i.e., information flow, divisibility and quantum mutual information. However, for the random unitary channel non-Markovian conditions are same to that of the information flow, but is different from that of the divisibility and quantum mutual information. Supported by the National Natural Science Foundation of China under Grant No. 61505053, the Natural Science Foundation of Hunan Province under Grant No. 2015JJ3092, the Research Foundation of Education Bureau of Hunan Province, China under Grant No. 16B177, the School Foundation from the Hunan University of Arts and Science under Grant No. 14ZD01

  13. Quantum Metrology in Non-Markovian Environments

    CERN Document Server

    Chin, Alex W; Plenio, Martin B

    2011-01-01

    We analyze optimal bounds for precision spectroscopy in the presence of general, non-Markovian phase noise. We demonstrate that the metrological equivalence of product and maximally entangled states that holds under Markovian dephasing fails in the non-Markovian case. Using an exactly solvable model of a physically realistic finite band-width dephasing environment, we show that the ensuing non-Markovian dynamics enables quantum correlated states to outperform metrological strategies based on uncorrelated states but otherwise identical resources. We show that this conclusion is a direct result of the coherent dynamics of the global state of the system and environment and, as a result, possesses general validity that goes beyond specific models.

  14. Non-Markovianity assisted Steady State Entanglement

    CERN Document Server

    Huelga, Susana F; Plenio, Martin B

    2011-01-01

    We analyze the dependence of steady state entanglement in a dimer system with a coherent exchange interaction and subject to local dephasing on the degree of Markovianity of the system-environment interaction. We demonstrate that non-Markovianity of the system-environment interaction is an essential resource that may support the formation of steady state entanglement whereas purely Markovian dynamics governed by Lindblad master equations results in separable steady states. This result illustrates possible mechanisms leading to long lived entanglement in purely decohering local environments. A feasible experimental demonstration of this non-Markovianity assisted steady state entanglement using a system of trapped ions is presented.

  15. On Non-Markovian Quantum Evolution

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej

    2013-01-01

    We analyze two measures of non-Markovianity: one based on the mathematical concept of divisibility of the dynamical map and the other one based on distinguishability of quantum states. We provide a simple example of qubit dynamic to show that these two measures need not agree. In addition, we discuss possible generalizations and intricate relations between these measures.

  16. Exact Closed Master Equation for Gaussian Non-Markovian Dynamics.

    Science.gov (United States)

    Ferialdi, L

    2016-03-25

    Non-Markovian master equations describe general open quantum systems when no approximation is made. We provide the exact closed master equation for the class of Gaussian, completely positive, trace preserving, non-Markovian dynamics. This very general result allows us to investigate a vast variety of physical systems. We show that the master equation for non-Markovian quantum Brownian motion is a particular case of our general result. Furthermore, we derive the master equation unraveled by a non-Markovian, dissipative stochastic Schrödinger equation, paving the way for the analysis of dissipative non-Markovian collapse models.

  17. Non-Markovianity of Gaussian Channels.

    Science.gov (United States)

    Torre, G; Roga, W; Illuminati, F

    2015-08-14

    We introduce a necessary and sufficient criterion for the non-Markovianity of Gaussian quantum dynamical maps based on the violation of divisibility. The criterion is derived by defining a general vectorial representation of the covariance matrix which is then exploited to determine the condition for the complete positivity of partial maps associated with arbitrary time intervals. Such construction does not rely on the Choi-Jamiolkowski representation and does not require optimization over states.

  18. Quantum metrology in non-Markovian environments.

    Science.gov (United States)

    Chin, Alex W; Huelga, Susana F; Plenio, Martin B

    2012-12-07

    We analyze precision bounds for a local phase estimation in the presence of general, non-Markovian phase noise. We demonstrate that the metrological equivalence of product and maximally entangled states that holds under strictly Markovian dephasing fails in the non-Markovian case. Using an exactly solvable model of a physically realistic finite bandwidth dephasing environment, we demonstrate that the ensuing non-Markovian dynamics enables quantum correlated states to outperform metrological strategies based on uncorrelated states using otherwise identical resources. We show that this conclusion is a direct result of the coherent dynamics of the global state of the system and environment and therefore the obtained scaling with the number of particles, which surpasses the standard quantum limit but does not achieve Heisenberg resolution, possesses general validity that goes beyond specific models. This is in marked contrast with the situation encountered under general Markovian noise, where an arbitrarily small amount of noise is enough to restore the scaling dictated by the standard quantum limit.

  19. Colloquium: Non-Markovian dynamics in open quantum systems

    Science.gov (United States)

    Breuer, Heinz-Peter; Laine, Elsi-Mari; Piilo, Jyrki; Vacchini, Bassano

    2016-04-01

    The dynamical behavior of open quantum systems plays a key role in many applications of quantum mechanics, examples ranging from fundamental problems, such as the environment-induced decay of quantum coherence and relaxation in many-body systems, to applications in condensed matter theory, quantum transport, quantum chemistry, and quantum information. In close analogy to a classical Markovian stochastic process, the interaction of an open quantum system with a noisy environment is often modeled phenomenologically by means of a dynamical semigroup with a corresponding time-independent generator in Lindblad form, which describes a memoryless dynamics of the open system typically leading to an irreversible loss of characteristic quantum features. However, in many applications open systems exhibit pronounced memory effects and a revival of genuine quantum properties such as quantum coherence, correlations, and entanglement. Here recent theoretical results on the rich non-Markovian quantum dynamics of open systems are discussed, paying particular attention to the rigorous mathematical definition, to the physical interpretation and classification, as well as to the quantification of quantum memory effects. The general theory is illustrated by a series of physical examples. The analysis reveals that memory effects of the open system dynamics reflect characteristic features of the environment which opens a new perspective for applications, namely, to exploit a small open system as a quantum probe signifying nontrivial features of the environment it is interacting with. This Colloquium further explores the various physical sources of non-Markovian quantum dynamics, such as structured environmental spectral densities, nonlocal correlations between environmental degrees of freedom, and correlations in the initial system-environment state, in addition to developing schemes for their local detection. Recent experiments addressing the detection, quantification, and control of

  20. Non-Markovianity, coherence, and system-environment correlations in a long-range collision model

    Science.gov (United States)

    Ćakmak, B.; Pezzutto, M.; Paternostro, M.; Müstecaplıoǧlu, Ö. E.

    2017-08-01

    We consider the dynamics of a collisional model in which both the system and environment are embodied by spin-1 /2 particles. In order to include non-Markovian features in our model, we introduce interactions among the environmental qubits and investigate the effect that different models of such interaction have on the degree of non-Markovianity of the system's dynamics. By extending that interaction beyond the nearest neighbor, we enhance the degree of non-Markovianity in the system's dynamics. A further significant increase can be observed if a collective interaction with the forthcoming environmental qubits is considered. However, the observed degree of non-Markovianity in this case is nonmonotonic with the increasing number of qubits included in the interaction. Moreover, one can establish a connection between the degree of non-Markovianity in the evolution of the system and the fading behavior of quantum coherence in its state as the number of collisions grows. We complement our study with an investigation of system-environment correlations and present an example of their importance on a physical upper bound on the trace distance derivative.

  1. Non-Markovian Dynamics of Quantum Systems

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej

    2011-01-01

    We analyze a local approach to the non-Markovian evolution of open quantum systems. It turns out that any dynamical map representing evolution of such a system may be described either by non-local master equation with memory kernel or equivalently by equation which is local in time. The price one pays for the local approach is that the corresponding generator might be highly singular and it keeps the memory about the starting point 't0'. Remarkably, singularities of generator may lead to interesting physical phenomena like revival of coherence or sudden death and revival of entanglement.

  2. Entanglement and non-markovianity of quantum evolutions.

    Science.gov (United States)

    Rivas, Angel; Huelga, Susana F; Plenio, Martin B

    2010-07-30

    We address the problem of quantifying the non-markovian character of quantum time evolutions of general systems in contact with an environment. We introduce two different measures of non-markovianity that exploit the specific traits of quantum correlations and are suitable for opposite experimental contexts. When complete tomographic knowledge about the evolution is available, our measure provides a necessary and sufficient condition to quantify strictly the non-markovianity. In the opposite case, when no information whatsoever is available, we propose a sufficient condition for non-markovianity. Remarkably, no optimization procedure underlies our derivation, which greatly enhances the practical relevance of the proposed criteria.

  3. Using non-Markovian measures to evaluate quantum master equations for photosynthesis

    Science.gov (United States)

    Chen, Hong-Bin; Lambert, Neill; Cheng, Yuan-Chung; Chen, Yueh-Nan; Nori, Franco

    2015-08-01

    When dealing with system-reservoir interactions in an open quantum system, such as a photosynthetic light-harvesting complex, approximations are usually made to obtain the dynamics of the system. One question immediately arises: how good are these approximations, and in what ways can we evaluate them? Here, we propose to use entanglement and a measure of non-Markovianity as benchmarks for the deviation of approximate methods from exact results. We apply two frequently-used perturbative but non-Markovian approximations to a photosynthetic dimer model and compare their results with that of the numerically-exact hierarchy equation of motion (HEOM). This enables us to explore both entanglement and non-Markovianity measures as means to reveal how the approximations either overestimate or underestimate memory effects and quantum coherence. In addition, we show that both the approximate and exact results suggest that non-Markonivity can, counter-intuitively, increase with temperature, and with the coupling to the environment.

  4. Quantum trajectories under frequent measurements in a non-Markovian environment

    Science.gov (United States)

    Xu, Luting; Li, Xin-Qi

    2016-09-01

    In this work we generalize the quantum trajectory (QT) theory from Markovian to non-Markovian environments. We model the non-Markovian environment by using a Lorentzian spectral density function with bandwidth (Λ ), and find a perfect "scaling" property with the measurement frequency (τ-1) in terms of the scaling variable x =Λ τ . Our result bridges the gap between the existing QT theory and the Zeno effect, by rendering them as two extremes corresponding to x →∞ and x →0 , respectively. This x -dependent criterion improves the idea of using τ alone and quantitatively identifies the validity condition of the conventional QT theory.

  5. General non-Markovian dynamics of open quantum systems.

    Science.gov (United States)

    Zhang, Wei-Min; Lo, Ping-Yuan; Xiong, Heng-Na; Tu, Matisse Wei-Yuan; Nori, Franco

    2012-10-26

    We present a general theory of non-Markovian dynamics for open systems of noninteracting fermions (bosons) linearly coupled to thermal environments of noninteracting fermions (bosons). We explore the non-Markovian dynamics by connecting the exact master equations with the nonequilibirum Green's functions. Environmental backactions are fully taken into account. The non-Markovian dynamics consists of nonexponential decays and dissipationless oscillations. Nonexponential decays are induced by the discontinuity in the imaginary part of the self-energy corrections. Dissipationless oscillations arise from band gaps or the finite band structure of spectral densities. The exact analytic solutions for various non-Markovian thermal environments show that non-Markovian dynamics can be largely understood from the environmental-modified spectra of open systems.

  6. Non-Markovian Quantum State Diffusion

    CERN Document Server

    Diósi, L; Strunz, W T

    1998-01-01

    We present a nonlinear stochastic Schroedinger equation for pure states describing non-Markovian diffusion of quantum trajectories. It provides an unravelling of the evolution of a quantum system coupled to a finite or infinite number of harmonic oscillators, without any approximation. Its power is illustrated by several examples, including measurement-like situations, dissipation, and quantum Brownian motion. In some examples, we treat the environment phenomenologically as an infinite reservoir with fluctuations of arbitrary correlation. In other examples the environment consists of a finite number of oscillators. In these quasi-periodic cases we see the reversible decay of a `Schroedinger cat' state. Finally, our description of open systems is compatible with different positions of the `Heisenberg cut' between system and environment.

  7. Non-Markovian signatures in the current noise of a charge qubit

    DEFF Research Database (Denmark)

    Braggio, A.; Flindt, Christian; Novotny, T.

    2008-01-01

    We investigate the current noise of a charge qubit coupled to a phonon bath in different parameter regimes. We find, using the theory of Full Counting Statistics of non-Markovian systems, that the current fluctuations are strongly influenced by memory effects generated from the interplay between ...

  8. Dynamics of non-Markovianity in the presence of a driving field

    Indian Academy of Sciences (India)

    Mandani Somayeh; Sarbishaei Mohsen; Javidan Kurosh

    2016-03-01

    We investigate a two-level system in a cavity QED by considering the effects ofamplitude damping, phase damping and driving field. We have studied the non-Markovianity in resonance and non-resonance limits in the presence of these effects using Breuer–Laine–Piilo (BLP) non-Markovianity measure ($N_{\\rm BLP}$). The evolution of the system is derived using the time convolutionless (TCL) master equation. In some conditions, it is shown that in the presence of a driving field, the $N_{\\rm BLP} increases in the resonance and non-resonance limits. We have also found the exact solution of the master equation in order to investigate the effect of temperature- and environment excited states. We have shown that the behaviour of non-Markovianity is very different from what one can see from the TCL approach. We have also presented some explanation about the behaviour of non-Markovianity in the exact solution using quantum discord (QD).

  9. Light with Tunable Non-Markovian Phase Imprint

    Science.gov (United States)

    Fischer, Robert; Vidal, Itamar; Gilboa, Doron; Correia, Ricardo R. B.; Ribeiro-Teixeira, Ana C.; Prado, Sandra D.; Hickman, Jandir; Silberberg, Yaron

    2015-08-01

    We introduce a simple and flexible method to generate spatially non-Markovian light with tunable coherence properties in one and two dimensions. The unusual behavior of this light is demonstrated experimentally by probing the far field and by recording its diffraction pattern after a double slit: In both cases we observe, instead of a central intensity maximum, a line- or cross-shaped dark region, whose width and profile depend on the non-Markovian coherence properties. Because these properties can be controlled and easily reproduced in experiment, the presented approach lends itself to serving as a test bed to study and gain a deeper understanding of non-Markovian processes.

  10. Light with tunable non-Markovian phase imprint

    CERN Document Server

    Fischer, Robert; Gilboa, Doron; Correia, Ricardo R B; Ribeiro-Teixeira, Ana C; Prado, Sandra D; Hickman, Jandir; Silberberg, Yaron

    2015-01-01

    We introduce a simple and flexible method to generate spatially non-Markovian light with tunable coherence properties in one and two dimensions. The unusual behavior of this light is demonstrated experimentally by probing the far field and recording its diffraction pattern after a double slit: In both cases we observe instead of a central intensity maximum a line or cross shaped dark region, whose width and profile depend on the non-Markovian coherence properties. Since these properties can be controlled and easily reproduced in experiment, the presented approach lends itself to serve as a testbed to gain a deeper understanding of non-Markovian processes.

  11. Linear Optics Simulation of Non-Markovian Quantum Dynamics

    CERN Document Server

    Chiuri, Andrea; Mazzola, Laura; Paternostro, Mauro; Mataloni, Paolo

    2012-01-01

    The simulation of quantum processes is a key goal for the grand programme aiming at grounding quantum technologies as the way to explore complex phenomena that are inaccessible through standard, classical calculators. Some interesting steps have been performed in this direction and this scenario has recently been extended to open quantum evolutions, marking the possibility to investigate important features of the way a quantum system interacts with its environment. Here we demonstrate experimentally the (non-)Markovianity of a process where system and environment are coupled through a simulated transverse Ising model. By engineering the evolution in a fully controlled photonic quantum simulator, we assess and demonstrate the role that system-environment correlations have in the emergence of memory effects.

  12. Fermionic-mode entanglement in non-Markovian environment

    Science.gov (United States)

    Cheng, Jiong; Han, Yan; An, Qing-zhi; Zhou, Ling

    2015-03-01

    We evaluate the non-Markovian effects on the entanglement dynamics of a fermionic system interacting with two dissipative vacuum reservoirs. The exact solution of density matrix is derived by utilizing the Feynman-Vernon influence functional theory in the fermionic coherent state representation and the Grassmann calculus, which are valid for both the fermionic and bosonic baths, and their difference lies in the dependence of the parity of the initial states. The fermionic entanglement dynamics is presented by adding an additional restriction to the density matrix known as the superselection rules. Our analysis shows that the usual decoherence suppression schemes implemented in qubits systems can also be achieved for systems of identical fermions, and the initial state proves its importance in the evolution of fermionic entanglement. Our results provide a potential way to decoherence controlling of identical fermions.

  13. On Non-Markovian Time Evolution in Open Quantum Systems

    Science.gov (United States)

    Kossakowski, Andrzej; Rebolledo, Rolando

    2008-03-01

    Non-Markovian reduced dynamics of an open system is investigated. In the case the initial state of the reservoir is the vacuum state, an approximation is introduced which makes possible to construct a reduced dynamics which is completely positive.

  14. Non-Markovian spontaneous emission from a single quantum dot

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg; Ates, Serkan; Lund-Hansen, Toke;

    2011-01-01

    We observe non-Markovian dynamics of a single quantum dot when tuned into resonance with a cavity mode. Excellent agreement between experiment and theory is observed providing the first quantitative description of such a system....

  15. Non-Markovian Quantum Jumps in Excitonic Energy Transfer

    CERN Document Server

    Rebentrost, Patrick; Aspuru-Guzik, Alan

    2009-01-01

    We utilize the novel non-Markovian quantum jump (NMQJ) approach to stochastically simulate exciton dynamics derived from a time-convolutionless master equation. For relevant parameters and time scales, the time-dependent, oscillatory decoherence rates can have negative regions, a signature of non-Markovian behavior and of the revival of coherences. This can lead to non-Markovian population beatings for a dimer system at room temperature. We show that strong exciton-phonon coupling to low frequency modes can considerably modify transport properties. We observe increased exciton transport, which can be seen as an extension of recent environment-assisted quantum transport (ENAQT) concepts to the non-Markovian regime. Within the NMQJ method, the Fenna-Matthew-Olson protein is investigated as a prototype for larger photosynthetic complexes.

  16. Decision-Theoretic Planning with non-Markovian Rewards

    CERN Document Server

    Gretton, C; Price, D; Slaney, J; Thiebaux, S

    2011-01-01

    A decision process in which rewards depend on history rather than merely on the current state is called a decision process with non-Markovian rewards (NMRDP). In decision-theoretic planning, where many desirable behaviours are more naturally expressed as properties of execution sequences rather than as properties of states, NMRDPs form a more natural model than the commonly adopted fully Markovian decision process (MDP) model. While the more tractable solution methods developed for MDPs do not directly apply in the presence of non-Markovian rewards, a number of solution methods for NMRDPs have been proposed in the literature. These all exploit a compact specification of the non-Markovian reward function in temporal logic, to automatically translate the NMRDP into an equivalent MDP which is solved using efficient MDP solution methods. This paper presents NMRDPP (Non-Markovian Reward Decision Process Planner), a software platform for the development and experimentation of methods for decision-theoretic planning...

  17. Entanglement and non-Markovianity of quantum evolutions

    CERN Document Server

    Rivas, Ángel; Plenio, Martin B

    2009-01-01

    We address the problem of quantifying the non-Markovian character of quantum time-evolutions of general systems in contact with an environment. We introduce two different measures of non-Markovianity that exploit the specific traits of quantum correlations and are suitable for opposite experimental contexts, one requiring complete tomographic knowledge about the evolution and the other one requiring no knowledge at all. Remarkably, no optimization procedure underlies our derivation, which greatly enhances the practical relevance of the proposed criteria.

  18. Non-Markovian dynamics of open quantum systems

    Science.gov (United States)

    Fleming, Chris H.

    An open quantum system is a quantum system that interacts with some environment whose degrees of freedom have been coarse grained away. This model describes non-equilibrium processes more general than scattering-matrix formulations. Furthermore, the microscopically-derived environment provides a model of noise, dissipation and decoherence far more general than Markovian (white noise) models. The latter are fully characterized by Lindblad equations and can be motivated phenomenologically. Non-Markovian processes consistently account for backreaction with the environment and can incorporate effects such as finite temperature and spatial correlations. We consider linear systems with bilinear coupling to the environment, or quantum Brownian motion, and nonlinear systems with weak coupling to the environment. For linear systems we provide exact solutions with analytical results for a variety of spectral densities. Furthermore, we point out an important mathematical subtlety which led to incorrect master-equation coefficients in earlier derivations, given nonlocal dissipation. For nonlinear systems we provide perturbative solutions by translating the formalism of canonical perturbation theory into the context of master equations. It is shown that unavoidable degeneracy causes an unfortunate reduction in accuracy between perturbative master equations and their solutions. We also extend the famous theorem of Lindblad, Gorini, Kossakowski and Sudarshan on completely positivity to non-Markovian master equations. Our application is primarily to model atoms interacting via a common electromagnetic field. The electromagnetic field contains correlations in both space and time, which are related to its relativistic (photon-mediated) nature. As such, atoms residing in the same field experience different environmental effects depending upon their relative position and orientation. Our more accurate solutions were necessary to assess sudden death of entanglement at zero temperature

  19. Non-Markovian expansion in quantum Brownian motion

    Science.gov (United States)

    Fraga, Eduardo S.; Krein, Gastão; Palhares, Letícia F.

    2014-01-01

    We consider the non-Markovian Langevin evolution of a dissipative dynamical system in quantum mechanics in the path integral formalism. After discussing the role of the frequency cutoff for the interaction of the system with the heat bath and the kernel and noise correlator that follow from the most common choices, we derive an analytic expansion for the exact non-Markovian dissipation kernel and the corresponding colored noise in the general case that is consistent with the fluctuation-dissipation theorem and incorporates systematically non-local corrections. We illustrate the modifications to results obtained using the traditional (Markovian) Langevin approach in the case of the exponential kernel and analyze the case of the non-Markovian Brownian motion. We present detailed results for the free and the quadratic cases, which can be compared to exact solutions to test the convergence of the method, and discuss potentials of a general nonlinear form.

  20. Non-Markovian expansion in quantum dissipative systems

    CERN Document Server

    Fraga, E S; Palhares, L F

    2009-01-01

    We consider the non-Markovian Langevin evolution of a dissipative dynamical system in quantum mechanics in the path integral formalism. After discussing the role of the frequency cutoff for the interaction of the system with the heat bath and the kernel and noise correlator that follow from the most common choices, we derive an analytic expansion for the exact non-Markovian dissipation kernel and the corresponding colored noise in the general case that is consistent with the fluctuation-dissipation theorem and incorporates systematically non-local corrections. We illustrate the modifications to results obtained using the traditional (Markovian) Langevin approach in the case of the exponential kernel and analyze the case of the non-Markovian Brownian motion.

  1. Non-Markovian diffusion equations and processes: analysis and simulations

    CERN Document Server

    Mura, Antonio; Mainardi, Francesco

    2007-01-01

    In this paper we introduce and analyze a class of diffusion type equations related to certain non-Markovian stochastic processes. We start from the forward drift equation which is made non-local in time by the introduction of a suitable chosen memory kernel K(t). The resulting non-Markovian equation can be interpreted in a natural way as the evolution equation of the marginal density function of a random time process l(t). We then consider the subordinated process Y(t)=X(l(t)) where X(t) is a Markovian diffusion. The corresponding time-evolution of the marginal density function of Y(t) is governed by a non-Markovian Fokker-Planck equation which involves the memory kernel K(t). We develop several applications and derive the exact solutions. We consider different stochastic models for the given equations providing path simulations.

  2. Implications of non-Markovian quantum dynamics for the Landauer bound

    Science.gov (United States)

    Pezzutto, Marco; Paternostro, Mauro; Omar, Yasser

    2016-12-01

    We study the dynamics of a spin-1/2 particle interacting with a multi-spin environment, modelling the corresponding open system dynamics through a collision-based model. The environmental particles are prepared in individual thermal states, and we investigate the effects of a distribution of temperatures across the spin environment on the evolution of the system, particularly how thermalisation in the long-time limit is affected. We study the phenomenology of the heat exchange between system and environment and consider the information-to-energy conversion process, induced by the system-environment interaction and embodied by the Landauer principle. Furthermore, by considering an interacting-particles environment, we tune the dynamics of the system from an explicit Markovian evolution up to a strongly non-Markovian one, investigating the connections between non-Markovianity, the establishment of system-environment correlations, and the breakdown of the validity of Landauer principle.

  3. Using non-Markovian measures to evaluate quantum master equations for photosynthesis

    Science.gov (United States)

    Chen, Hong-Bin; Lambert, Neill; Cheng, Yuan-Chung; Chen, Yueh-Nan; Nori, Franco

    2015-01-01

    When dealing with system-reservoir interactions in an open quantum system, such as a photosynthetic light-harvesting complex, approximations are usually made to obtain the dynamics of the system. One question immediately arises: how good are these approximations, and in what ways can we evaluate them? Here, we propose to use entanglement and a measure of non-Markovianity as benchmarks for the deviation of approximate methods from exact results. We apply two frequently-used perturbative but non-Markovian approximations to a photosynthetic dimer model and compare their results with that of the numerically-exact hierarchy equation of motion (HEOM). This enables us to explore both entanglement and non-Markovianity measures as means to reveal how the approximations either overestimate or underestimate memory effects and quantum coherence. In addition, we show that both the approximate and exact results suggest that non-Markonivity can, counter-intuitively, increase with temperature, and with the coupling to the environment. PMID:26238479

  4. On measures of non-Markovianity: divisibility vs. Markovianity

    CERN Document Server

    Chruściński, Dariusz

    2011-01-01

    We analyze two recently proposed measure of non-Markovianity: one based on the concept of divisibility of the dynamical map and the other one based on distinguishability of quantum states. We provide a toy model to show that these two measures need not agree. Finally, we discuss possible generalizations and intricate relations between these measures.

  5. Measures of non-Markovianity: Divisibility versus backflow of information

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej; Rivas, Ángel

    2011-05-01

    We analyze two recently proposed measures of non-Markovianity: one based on the concept of divisibility of the dynamical map and the other one based on distinguishability of quantum states. We provide a model to show that these two measures need not agree. In addition, we discuss possible generalizations and intricate relations between these measures.

  6. Counting statistics of non-markovian quantum stochastic processes

    DEFF Research Database (Denmark)

    Flindt, Christian; Novotny, T.; Braggio, A.

    2008-01-01

    We derive a general expression for the cumulant generating function (CGF) of non-Markovian quantum stochastic transport processes. The long-time limit of the CGF is determined by a single dominating pole of the resolvent of the memory kernel from which we extract the zero-frequency cumulants of t...

  7. Quantum non-Markovianity induced by Anderson localization

    Science.gov (United States)

    Lorenzo, Salvatore; Lombardo, Federico; Ciccarello, Francesco; Palma, G. Massimo

    2017-02-01

    As discovered by P. W. Anderson, excitations do not propagate freely in a disordered lattice, but, due to destructive interference, they localise. As a consequence, when an atom interacts with a disordered lattice, one indeed observes a non-trivial excitation exchange between atom and lattice. Such non-trivial atomic dynamics will in general be characterised also by a non-trivial quantum information backflow, a clear signature of non-Markovian dynamics. To investigate the above scenario, we consider a quantum emitter, or atom, weakly coupled to a uniform coupled-cavity array (CCA). If initially excited, in the absence of disorder, the emitter undergoes a Markovian spontaneous emission by releasing all its excitation into the CCA (initially in its vacuum state). By introducing static disorder in the CCA the field normal modes become Anderson-localized, giving rise to a non-Markovian atomic dynamics. We show the existence of a functional relationship between a rigorous measure of quantum non-Markovianity and the CCA localization. We furthermore show that the average non-Markovianity of the atomic dynamics is well-described by a phenomenological model in which the atom is coupled, at the same time, to a single mode and to a standard - Markovian - dissipative bath.

  8. Quantum non-Markovianity induced by Anderson localization

    Science.gov (United States)

    Lorenzo, Salvatore; Lombardo, Federico; Ciccarello, Francesco; Palma, G. Massimo

    2017-01-01

    As discovered by P. W. Anderson, excitations do not propagate freely in a disordered lattice, but, due to destructive interference, they localise. As a consequence, when an atom interacts with a disordered lattice, one indeed observes a non-trivial excitation exchange between atom and lattice. Such non-trivial atomic dynamics will in general be characterised also by a non-trivial quantum information backflow, a clear signature of non-Markovian dynamics. To investigate the above scenario, we consider a quantum emitter, or atom, weakly coupled to a uniform coupled-cavity array (CCA). If initially excited, in the absence of disorder, the emitter undergoes a Markovian spontaneous emission by releasing all its excitation into the CCA (initially in its vacuum state). By introducing static disorder in the CCA the field normal modes become Anderson-localized, giving rise to a non-Markovian atomic dynamics. We show the existence of a functional relationship between a rigorous measure of quantum non-Markovianity and the CCA localization. We furthermore show that the average non-Markovianity of the atomic dynamics is well-described by a phenomenological model in which the atom is coupled, at the same time, to a single mode and to a standard - Markovian - dissipative bath. PMID:28205542

  9. Open system dynamics with non-Markovian quantum trajectories

    CERN Document Server

    Strunz, W T; Gisin, Nicolas; Strunz, Walter T; Diosi, Lajos; Gisin, Nicolas

    1999-01-01

    A non-Markovian stochastic Schroedinger equation for a quantum system coupled to an environment of harmonic oscillators is presented. Its solutions, when averaged over the noise, reproduce the standard reduced density operator without any approximation. We illustrate the power of this approach with several examples, including exponentially decaying bath correlations and extreme non-Markovian cases, where the `environment' consists of only a single oscillator. The latter case shows the decay and revival of a `Schroedinger cat' state. For strong coupling to a dissipative environment with memory, the asymptotic state can be reached in a finite time. Our description of open systems is compatible with different positions of the `Heisenberg cut' between system and environment.

  10. Non-Markovian Quantum Dynamics: Local versus Nonlocal

    Science.gov (United States)

    Chruściński, Dariusz; Kossakowski, Andrzej

    2010-02-01

    We analyze non-Markovian evolution of open quantum systems. It is shown that any dynamical map representing the evolution of such a system may be described either by a nonlocal master equation with a memory kernel or equivalently by an equation which is local in time. These two descriptions are complementary: if one is simple, the other is quite involved, or even singular, and vice versa. The price one pays for the local approach is that the corresponding generator keeps the memory about the starting point “t0.” This is the very essence of non-Markovianity. Interestingly, this generator might be highly singular; nevertheless, the corresponding dynamics is perfectly regular. Remarkably, the singularities of the generator may lead to interesting physical phenomena such as the revival of coherence or sudden death and revival of entanglement.

  11. Non-Markovian quantum dynamics: local versus non-local

    CERN Document Server

    Chruscinski, Dariusz

    2009-01-01

    We analyze non-Markovian evolution of open quantum systems. It is shown that any dynamical map representing evolution of such a system may be described either by non-local master equation with memory kernel or equivalently by equation which is local in time. Theses two descriptions are complementary: if one is simple the other is quite involved, or even singular, and vice versa. The price one pays for the local approach is that the corresponding generator keeps the memory about the starting point `t_0'. This is the very essence of non-Markovianity. Interestingly, this generator might be highly singular, nevertheless, the corresponding dynamics is perfectly regular. Remarkably, singularities of generator may lead to interesting physical phenomena like revival of coherence or sudden death and revival of entanglement.

  12. The Entropy Production Distribution in Non-Markovian Thermal Baths

    Directory of Open Access Journals (Sweden)

    José Inés Jiménez-Aquino

    2014-03-01

    Full Text Available In this work we study the distribution function for the total entropy production of a Brownian particle embedded in a non-Markovian thermal bath. The problem is studied in the overdamped approximation of the generalized Langevin equation, which accounts for a friction memory kernel characteristic of a Gaussian colored noise. The problem is studied in two physical situations: (i when the particle in the harmonic trap is subjected to an arbitrary time-dependent driving force; and (ii when the minimum of the harmonic trap is arbitrarily dragged out of equilibrium by an external force. By assuming a natural non Markovian canonical distribution for the initial conditions, the distribution function for the total entropy production becomes a non Gaussian one. Its characterization is then given through the first three cumulants.

  13. Non-Markovian entanglement dynamics in coupled superconducting qubit systems

    CERN Document Server

    Cui, Wei; Pan, Yu

    2010-01-01

    We theoretically analyze the entanglement generation and dynamics by coupled Josephson junction qubits. Considering a current-biased Josephson junction (CBJJ), we generate maximally entangled states. In particular, the entanglement dynamics is considered as a function of the decoherence parameters, such as the temperature, the ratio $r\\equiv\\omega_c/\\omega_0$ between the reservoir cutoff frequency $\\omega_c$ and the system oscillator frequency $\\omega_0$, % between $\\omega_0$ the characteristic frequency of the %quantum system of interest, and $\\omega_c$ the cut-off frequency of %Ohmic reservoir and the energy levels split of the superconducting circuits in the non-Markovian master equation. We analyzed the entanglement sudden death (ESD) and entanglement sudden birth (ESB) by the non-Markovian master equation. Furthermore, we find that the larger the ratio $r$ and the thermal energy $k_BT$, the shorter the decoherence. In this superconducting qubit system we find that the entanglement can be controlled and t...

  14. Comparisons of different witnesses of non-Markovianity

    Science.gov (United States)

    Zuo, Wei; Qian, Xiao-Qing; Liang, Xian-Ting

    2017-01-01

    In this paper, the evolutions of two kinds of witnesses of the non-Markovianity and their rates of changes with time are investigated and compared. Four definitions, the trace distance, fidelity, quantum relative entropy, and quantum Fisher information are used for the first kind of witnesses which are based on the completely positive maps (CPM). Three definitions, the quantum entanglement, quantum mutual information, and quantum discord are used for the second kind of witnesses, and they are based on the local completely positive maps (LCPM). An open two-level quantum system model and a numerically quantum dissipative dynamics method, hierarchy equation of motion (HEM) are used in the investigations. It is shown that the evolutions of the witnesses and their rates of the changes calculated with different definitions clearly show the characteristics of the non-Markovianity and they are in agreement with each other.

  15. Computing the non-Markovian coarse-grained interactions derived from the Mori-Zwanzig formalism in molecular systems: Application to polymer melts.

    Science.gov (United States)

    Li, Zhen; Lee, Hee Sun; Darve, Eric; Karniadakis, George Em

    2017-01-07

    Memory effects are often introduced during coarse-graining of a complex dynamical system. In particular, a generalized Langevin equation (GLE) for the coarse-grained (CG) system arises in the context of Mori-Zwanzig formalism. Upon a pairwise decomposition, GLE can be reformulated into its pairwise version, i.e., non-Markovian dissipative particle dynamics (DPD). GLE models the dynamics of a single coarse particle, while DPD considers the dynamics of many interacting CG particles, with both CG systems governed by non-Markovian interactions. We compare two different methods for the practical implementation of the non-Markovian interactions in GLE and DPD systems. More specifically, a direct evaluation of the non-Markovian (NM) terms is performed in LE-NM and DPD-NM models, which requires the storage of historical information that significantly increases computational complexity. Alternatively, we use a few auxiliary variables in LE-AUX and DPD-AUX models to replace the non-Markovian dynamics with a Markovian dynamics in a higher dimensional space, leading to a much reduced memory footprint and computational cost. In our numerical benchmarks, the GLE and non-Markovian DPD models are constructed from molecular dynamics (MD) simulations of star-polymer melts. Results show that a Markovian dynamics with auxiliary variables successfully generates equivalent non-Markovian dynamics consistent with the reference MD system, while maintaining a tractable computational cost. Also, transient subdiffusion of the star-polymers observed in the MD system can be reproduced by the coarse-grained models. The non-interacting particle models, LE-NM/AUX, are computationally much cheaper than the interacting particle models, DPD-NM/AUX. However, the pairwise models with momentum conservation are more appropriate for correctly reproducing the long-time hydrodynamics characterised by an algebraic decay in the velocity autocorrelation function.

  16. Efficient simulation of non-Markovian system-environment interaction

    CERN Document Server

    Rosenbach, Robert; Huelga, Susana F; Cao, Jianshu; Plenio, Martin Bodo

    2015-01-01

    In this work, we combine an established method for open quantum systems -- the time evolving density matrix using orthogonal polynomials algorithm (TEDOPA) -- with the transfer tensors formalism (TTM), a new tool for the analysis, compression and propagation of non-Markovian processes. This enables the investigation of previously inaccessible long-time dynamics, such as those ensuing from low temperature regimes with arbitrary, possibly highly structured, spectral densities. We briefly introduce both methods, followed by a benchmark to prove viability and combination synergies. Subsequently we illustrate the capabilities of this approach at the hand of specific examples and conclude our analysis by highlighting possible further applications of our method.

  17. Characterization of the degree of Musical non-Markovianity

    CERN Document Server

    Mannone, Maria

    2013-01-01

    Musical compositions could be characterized by a certain degree of memory, that takes into account repetitions and similarity of sequences of pitches, durations and intensities (the patterns). The higher the quantity of variations, the lower the degree of memory. This degree has never quantitatively been defined and measured. In physics, mathematical tools to quantify memory (defined as non-Markovianity) in quantum systems have been developed. The aim of this paper is to extend these mathematical tools to music, defining a general method to measure the degree of memory in musical compositions. Applications to some musical scores give results that agree with the expectations.

  18. Non- Markovian Quantum Stochastic Equation For Two Coupled Oscillators

    CERN Document Server

    Alpomishev, E X

    2016-01-01

    The system of nonlinear Langevin equations was obtained by using Hamiltonian's operator of two coupling quantum oscillators which are interacting with heat bath. By using the analytical solution of these equations, the analytical expressions for transport coefficients was found. Generalized Langevin equations and fluctuation-dissipation relations are derived for the case of a nonlinear non-Markovian noise. The explicit expressions for the time-dependent friction and diffusion coefficients are presented for the case of linear couplings in the coordinate between the collective two coupled harmonic oscillators and heat bath.

  19. Non-Markovian quantum Brownian motion of a harmonic oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.

    1994-02-01

    We apply the density-matrix method to the study of quantum Brownian motion of a harmonic oscillator coupled to a heat bath, a system investigated previously by Caldeira and Leggett using a different method. Unlike the earlier work, in our derivation of the master equation the non-Markovian terms are maintained. Although the same model of interaction is used, discrepancy is found between their results and our equation in the Markovian limit. We also point out that the particular interaction model used by both works cannot lead to the phenomenological generalized Langevin theory of Kubo.

  20. Experimental on-demand recovery of entanglement by local operations within non-Markovian dynamics.

    Science.gov (United States)

    Orieux, Adeline; D'Arrigo, Antonio; Ferranti, Giacomo; Lo Franco, Rosario; Benenti, Giuliano; Paladino, Elisabetta; Falci, Giuseppe; Sciarrino, Fabio; Mataloni, Paolo

    2015-02-25

    In many applications entanglement must be distributed through noisy communication channels that unavoidably degrade it. Entanglement cannot be generated by local operations and classical communication (LOCC), implying that once it has been distributed it is not possible to recreate it by LOCC. Recovery of entanglement by purely local control is however not forbidden in the presence of non-Markovian dynamics, and here we demonstrate in two all-optical experiments that such entanglement restoration can even be achieved on-demand. First, we implement an open-loop control scheme based on a purely local operation, without acquiring any information on the environment; then, we use a closed-loop scheme in which the environment is measured, the outcome controling the local operations on the system. The restored entanglement is a manifestation of "hidden" quantum correlations resumed by the local control. Relying on local control, both schemes improve the efficiency of entanglement sharing in distributed quantum networks.

  1. Non-Markovian dynamics of quantum coherence of two-level system driven by classical field

    Science.gov (United States)

    Huang, Zhiming; Situ, Haozhen

    2017-09-01

    In this paper, we study the quantum coherence dynamics of two-level atom system embedded in non-Markovian reservoir in the presence of classical driving field. We analyze the influence of memory effects, classical driving, and detuning on the quantum coherence. It is found that the quantum coherence has different behaviors in resonant case and non-resonant case. In the resonant case, in stark contrast with previous results, the strength of classical driving plays a negative effect on quantum coherence, while detuning parameter has the opposite effect. However, in non-resonant case through a long time, classical driving and detuning parameter have a different influence on quantum coherence compared with resonant case. Due to the memory effect of environment, in comparison with Markovian regime, quantum coherence presents vibrational variations in non-Markovian regime. In the resonant case, all quantum coherence converges to a fixed maximum value; in the non-resonant case, quantum coherence evolves to different stable values. For zero-coherence initial states, quantum coherence can be generated with evolution time. Our discussions and results should be helpful in manipulating and preserving the quantum coherence in dissipative environment with classical driving field.

  2. Objectivity in the non-Markovian spin-boson model

    Science.gov (United States)

    Lampo, Aniello; Tuziemski, Jan; Lewenstein, Maciej; Korbicz, Jarosław K.

    2017-07-01

    Objectivity constitutes one of the main features of the macroscopic classical world. An important aspect of the quantum-to-classical transition issue is to explain how such a property arises from the microscopic quantum theory. Recently, within the framework of open quantum systems, there has been proposed such a mechanism in terms of the so-called spectrum broadcast structures. These are multipartite quantum states of the system of interest and a part of its environment, assumed to be under an observation. This approach requires a departure from the standard open quantum systems methods, as the environment cannot be completely neglected. In the present paper we study the emergence of such a state structure in one of the canonical models of the condensed-matter theory: the spin-boson model, describing the dynamics of a two-level system coupled to an environment made up by a large number of harmonic oscillators. We pay much attention to the behavior of the model in the non-Markovian regime, in order to provide a testbed to analyze how the non-Markovian nature of the evolution affects the surfacing of a spectrum broadcast structure.

  3. Tripartite entanglement dynamics in the presence of Markovian or non-Markovian environment

    Science.gov (United States)

    Park, DaeKil

    2016-08-01

    We study on the tripartite entanglement dynamics when each party is initially entangled with other parties, but they locally interact with their own Markovian or non-Markovian environment. First we consider three GHZ-type initial states, all of which have GHZ-symmetry provided that the parameters are chosen appropriately. However, this symmetry is broken due to the effect of environment. The corresponding π -tangles, one of the tripartite entanglement measures, are analytically computed at arbitrary time. For Markovian case while the tripartite entanglement for type I exhibits an entanglement sudden death, the dynamics for the remaining cases decays normally in time with the half-life rule. For non-Markovian case the revival phenomenon of entanglement occurs after complete disappearance of entanglement. We also consider two W-type initial states. For both cases the π -tangles are analytically derived. The revival phenomenon also occurs in this case. On the analytical ground the robustness or fragility issue against the effect of environment is examined for both GHZ-type and W-type initial states.

  4. Quantum Monte-Carlo method applied to Non-Markovian barrier transmission

    CERN Document Server

    Hupin, G

    2010-01-01

    In nuclear fusion and fission, fluctuation and dissipation arise due to the coupling of collective degrees of freedom with internal excitations. Close to the barrier, both quantum, statistical and non-Markovian effects are expected to be important. In this work, a new approach based on quantum Monte-Carlo addressing this problem is presented. The exact dynamics of a system coupled to an environment is replaced by a set of stochastic evolutions of the system density. The quantum Monte-Carlo method is applied to systems with quadratic potentials. In all range of temperature and coupling, the stochastic method matches the exact evolution showing that non-Markovian effects can be simulated accurately. A comparison with other theories like Nakajima-Zwanzig or Time-ConvolutionLess ones shows that only the latter can be competitive if the expansion in terms of coupling constant is made at least to fourth order. A systematic study of the inverted parabola case is made at different temperatures and coupling constants....

  5. Quantum Monte Carlo method applied to non-Markovian barrier transmission

    Science.gov (United States)

    Hupin, Guillaume; Lacroix, Denis

    2010-01-01

    In nuclear fusion and fission, fluctuation and dissipation arise because of the coupling of collective degrees of freedom with internal excitations. Close to the barrier, quantum, statistical, and non-Markovian effects are expected to be important. In this work, a new approach based on quantum Monte Carlo addressing this problem is presented. The exact dynamics of a system coupled to an environment is replaced by a set of stochastic evolutions of the system density. The quantum Monte Carlo method is applied to systems with quadratic potentials. In all ranges of temperature and coupling, the stochastic method matches the exact evolution, showing that non-Markovian effects can be simulated accurately. A comparison with other theories, such as Nakajima-Zwanzig or time-convolutionless, shows that only the latter can be competitive if the expansion in terms of coupling constant is made at least to fourth order. A systematic study of the inverted parabola case is made at different temperatures and coupling constants. The asymptotic passing probability is estimated by different approaches including the Markovian limit. Large differences with an exact result are seen in the latter case or when only second order in the coupling strength is considered, as is generally assumed in nuclear transport models. In contrast, if fourth order in the coupling or quantum Monte Carlo method is used, a perfect agreement is obtained.

  6. Non-Markovian Quantum Fluctuations and Superradiance Near a Photonic Band Edge

    CERN Document Server

    Vats, N; Vats, Nipun; John, Sajeev

    1998-01-01

    We discuss a point model for the collective emission of light from N two-level atoms in a photonic bandgap material, each with an atomic resonant frequency near the edge of the gap. In the limit of a low initial occupation of the excited atomic state, our system is shown to possess novel atomic spectra and population statistics. For a high initial excited state population, mean field theory suggests a fractionalized inversion and a macroscopic polarization for the atoms in the steady state, both of which can be controlled by an external d.c. field. This atomic steady state is accompanied by a non--zero expectation value of the electric field operators for field modes located in the vicinity of the atoms. The nature of homogeneous broadening near the band edge is shown to differ markedly from that in free space due to non-Markovian memory effects in the radiation dynamics. Non-Markovian vacuum fluctuations are shown to yield a partially coherent steady state polarization with a random phase. In contrast with t...

  7. Non-Markovian Dynamics in Chiral Quantum Networks with Spins and Photons

    CERN Document Server

    Ramos, Tomás; Hauke, Philipp; Pichler, Hannes; Zoller, Peter

    2016-01-01

    We study the dynamics of chiral quantum networks consisting of nodes coupled by unidirectional or asymmetric bidirectional quantum channels. In contrast to the familiar photonic networks consisting of driven two-level atoms exchanging photons via 1D photonic nanostructures, we propose and study a setup where interactions between the atoms are mediated by spin excitations (magnons) in 1D XX-spin chains representing a spin waveguide. While Markovian quantum network theory eliminates quantum channels as structureless reservoirs in a Born-Markov approximation to obtain a master equation for the nodes, we are interested in non-Markovian dynamics. This arises from the nonlinear character of the dispersion with band-edge effects, and from finite spin propagation velocities leading to time delays in interactions. To account for the non-Markovian dynamics we treat the quantum degrees of freedom of the nodes and connecting channel as a composite spin system with the surrounding of the quantum network as a Markovian bat...

  8. Non-Markovian coarse-grained modeling of polymeric fluids based on the Mori-Zwanzig formalism

    Science.gov (United States)

    Li, Zhen; Bian, Xin; Li, Xiantao; Karniadakis, George

    The Mori-Zwanzig formalism for coarse-graining a complex dynamical system typically introduces memory effects. The Markovian assumption of delta-correlated fluctuating forces is often employed to simplify the formulation of coarse-grained (CG) models and numerical implementations. However, when the time scales of a system are not clearly separated, the memory effects become strong and the Markovian assumption becomes inaccurate. To this end, we incorporate memory effects into CG modeling by preserving non-Markovian interactions between CG variables based on the Mori-Zwanzig formalism. For a specific example, molecular dynamics (MD) simulations of star polymer melts are performed while the corresponding CG system is defined by grouping many bonded atoms into single clusters. Then, the effective interactions between CG clusters as well as the memory kernel are obtained from the MD simulations. The constructed CG force field with a memory kernel leads to a non-Markovian dissipative particle dynamics (NM-DPD). Quantitative comparisons on both static and dynamic properties between the CG models with Markovian and non-Markovian approximations will be presented. Supported by the DOE Center on Mathematics for Mesoscopic Modeling of Materials (CM4) and an INCITE grant.

  9. Reveal non-Markovianity of open quantum systems via local operations

    CERN Document Server

    Yang, Huan; Chen, Yanbei

    2011-01-01

    Non-Markovianity, as an important feature of general open quantum systems, is usually difficult to quantify with limited knowledge of how the plant that we are interested in interacts with its environment-the bath. It often happens that the reduced dynamics of the plant attached to a non-Markovian bath becomes indistinguishable from the one with a Markovian bath, if we left the entire system freely evolve. Here we show that non-Markovianity can be revealed via applying local unitary operations on the plant-they will influence the plant evolution at later times due to memory of the bath. This not only provides a new criterion for non-Markovianity, but also sheds light on protecting and recovering quantum coherence in non-Markovian systems, which will be useful for quantum-information processing.

  10. Markovian and non-Markovian dynamics in quantum and classical systems

    CERN Document Server

    Vacchini, Bassano; Laine, Elsi-Mari; Piilo, Jyrki; Breuer, Heinz-Peter

    2011-01-01

    We discuss the conceptually different definitions used for the non-Markovianity of classical and quantum processes. The well-established definition for non-Markovianity of a classical stochastic process represents a condition on the Kolmogorov hierarchy of the n-point joint probability distributions. Since this definition cannot be transferred to the quantum regime, quantum non-Markovianity has recently been defined and quantified in terms of the underlying quantum dynamical map, using either its divisibility properties or the behavior of the trace distance between pairs of initial states. Here, we investigate and compare these definitions and their relations to the classical notion of non-Markovianity by employing a large class of non-Markovian processes, known as semi-Markov processes, which admit a natural extension to the quantum case. A number of specific physical examples is constructed which allow to study the basic features of the classical and the quantum definitions and to evaluate explicitly the me...

  11. Non-Markovian barotropic-type and Hall-type fluctuation relations in crossed electric and magnetic fields

    Science.gov (United States)

    Jiménez-Aquino, J. I.; Romero-Bastida, M.

    2016-09-01

    In this paper we derive the non-Markovian barotropic-type and Hall-type fluctuation relations for noninteracting charged Brownian particles embedded in a memory heat bath and under the action of crossed electric and magnetic fields. We first obtain a more general non-Markovian fluctuation relation formulated within the context of a generalized Langevin equation with arbitrary friction memory kernel and under the action of a constant magnetic field and an arbitrary time-dependent electric field. It is shown that this fluctuation relation is related to the total amount of an effective work done on the charged particle as it is driven out of equilibrium by the applied time-dependent electric field. Both non-Markovian barotropic- and Hall-type fluctuation relations are then derived when the electric field is assumed to be also a constant vector pointing along just one axis. In the Markovian limit, we show explicitly that they reduce to the same results reported in the literature.

  12. Random phase wave: a soluble non-Markovian system

    Energy Technology Data Exchange (ETDEWEB)

    Dewar, R.L.

    1977-12-01

    The averaged propagator and the corresponding mass operator (non-Markovian particle-wave collision operator) of a particle being accelerated by a random potential are constructed explicitly in a model system. The model consists of an ensemble of monochromatic waves of random phase, such as arises in narrow-bandwidth plasma turbulence, and is particularly interesting as a system exhibiting strong trapping. An essential simplifying feature is that the propagator is evaluated in oscillation-center picture, which greatly simplifies the momentum-space operators occurring in the problem, and leads to a remarkable factorization of the mass operator. General analyticity and symmetry properties are derived using a projection-operator method, and verified for the solution of the model system. The nature of the memory exhibited by the mass operator is briefly examined.

  13. Quantum correlations dynamics under different non-markovian environmental models

    CERN Document Server

    Zhang, Ying-Jie; Shan, Chuan-Jia; Xia, Yun-Jie

    2011-01-01

    We investigate the roles of different environmental models on quantum correlation dynamics of two-qubit composite system interacting with two independent environments. The most common environmental models (the single-Lorentzian model, the squared-Lorentzian model, the two-Lorentzian model and band-gap model) are analyzed. First, we note that for the weak coupling regime, the monotonous decay speed of the quantum correlation is mainly determined by the spectral density functions of these different environments. Then, by considering the strong coupling regime we find that, contrary to what is stated in the weak coupling regime, the dynamics of quantum correlation depends on the non-Markovianity of the environmental models, and is independent of the environmental spectrum density functions.

  14. Closing the hierarchy for non-Markovian magnetization dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Tranchida, J., E-mail: julien.tranchida@cea.fr [CEA/DAM/Le Ripault, BP 16, F-37260 Monts (France); CNRS-Laboratoire de Mathématiques et Physique Théorique (UMR 7350), Fédération de Recherche “Denis Poisson” (FR2964), Département de Physique, Université de Tours, Parc de Grandmont, F-37200 Tours (France); Thibaudeau, P., E-mail: pascal.thibaudeau@cea.fr [CEA/DAM/Le Ripault, BP 16, F-37260 Monts (France); Nicolis, S., E-mail: stam.nicolis@lmpt.univ-tours.fr [CNRS-Laboratoire de Mathématiques et Physique Théorique (UMR 7350), Fédération de Recherche “Denis Poisson” (FR2964), Département de Physique, Université de Tours, Parc de Grandmont, F-37200 Tours (France)

    2016-04-01

    We propose a stochastic approach for the description of the time evolution of the magnetization of nanomagnets, that interpolates between the Landau–Lifshitz–Gilbert and the Landau–Lifshitz–Bloch approximations, by varying the strength of the noise. In addition, we take into account the autocorrelation time of the noise and explore the consequences, when it is finite, on the scale of the response of the magnetization, i.e. when it may be described as colored, rather than white, noise and non-Markovian features become relevant. We close the hierarchy for the moments of the magnetization, by introducing a suitable truncation scheme, whose validity is tested by direct numerical solution of the moment equations and compared to the average deduced from a numerical solution of the corresponding stochastic Langevin equation. In this way we establish a general framework that allows both coarse-graining simulations and faster calculations beyond the truncation approximation used here.

  15. Phenomena of limit cycle oscillations for non-Markovian dissipative systems undergoing long-time evolution%非马尔科夫耗散系统长时演化下的极限环振荡现象∗

    Institute of Scientific and Technical Information of China (English)

    游波; 岑理相

    2015-01-01

    Understanding the non-Markovian dynamics of dissipative processes induced by memory effects of the environment is a fundamental subject of open quantum systems. Because of the complexity of open quantum systems, e.g., the multiple energy scales involving that of the system, the environment, and their mutual coupling, it is generally a challenging task to characterize the relationship among the parameters of the system dynamics and the reservoir spectra. For the two-level spontaneous emission model within structured environments, it was shown in a recent literature (Opt. Lett. 38, 3650) that a functional relation could be established between the asymptotically non-decaying population and the spectral density of the reservoir as the system undergoes a long-time evolution. It hence renders a distinct perspective to look into the character of long-lived quantum coherence in the corresponding non-Markovian process. This article is devoted to further investigate the phenomena of limit cycle oscillations possibly occurring in such non-Markovian dissipative systems in a long-time evolution. For a two-level system subjected to an environment with Ohmic class spectra, due to the presence of a unique bound-state mode of the system, the evolution trajectory of the given initial states will converge to a limit cycle in the Bloch space. The dependence of the radius and the location of the limit cycle on the spectral density function of the reservoir are manifested by virtue of the described functional relation. For the model subjected to a photonic crystal environment with multiple bands, our studies reveal that, owing to the presence of two or more bound states, the evolution trajectory of the system will converge to a toric curve of a paraboloid in the Bloch space and the phenomena of periodic or quasi-periodic oscillations could exhibit. While the equation of the parabolic curve is fully determined by the initial values of the state vector in the Bloch space, our results

  16. Non-Markovian dynamics of a superconducting qubit in an open multimode resonator

    Science.gov (United States)

    Malekakhlagh, Moein; Petrescu, Alexandru; Türeci, Hakan E.

    2016-12-01

    We study the dynamics of a transmon qubit that is capacitively coupled to an open multimode superconducting resonator. Our effective equations are derived by eliminating resonator degrees of freedom while encoding their effect in the Green's function of the electromagnetic background. We account for the dissipation of the resonator exactly by employing a spectral representation for the Green's function in terms of a set of non-Hermitian modes and show that it is possible to derive effective Heisenberg-Langevin equations without resorting to the rotating-wave, two-level, Born, or Markov approximations. A well-behaved time-domain perturbation theory is derived to systematically account for the nonlinearity of the transmon. We apply this method to the problem of spontaneous emission, capturing accurately the non-Markovian features of the qubit dynamics, valid for any qubit-resonator coupling strength.

  17. Solvent fluctuations induce non-Markovian kinetics in hydrophobic pocket-ligand binding

    CERN Document Server

    Weiß, R Gregor; Dzubiella, Joachim

    2016-01-01

    We investigate the impact of water fluctuations on the key-lock association kinetics of a hydrophobic ligand (key) binding to a hydrophobic pocket (lock) by means of a minimalistic stochastic model system. It describes the collective hydration behavior of the pocket by bimodal fluctuations of a water-pocket interface that dynamically couples to the diffusive motion of the approaching ligand via the hydrophobic interaction. This leads to a set of overdamped Langevin equations in 2D-coordinate-space, that is Markovian in each dimension. Numerical simulations demonstrate locally increased friction of the ligand, decelerated binding kinetics, and local non-Markovian (memory) effects in the ligand's reaction coordinate as found previously in explicit-water molecular dynamics studies of model hydrophobic pocket-ligand binding [1,2]. Our minimalistic model elucidates the origin of effectively enhanced friction in the process that can be traced back to long-time decays in the force-autocorrelation function induced by...

  18. Non-markovian model of photon-assisted dephasing by electron-phonon interactions in a coupled quantum-dot-cavity system

    DEFF Research Database (Denmark)

    Nielsen, Per Kær; Nielsen, Torben Roland; Lodahl, Peter;

    2010-01-01

    We investigate the influence of electron-phonon interactions on the dynamical properties of a quantum-dot-cavity QED system. We show that non-Markovian effects in the phonon reservoir lead to strong changes in the dynamics, arising from photon-assisted dephasing processes, not present in Markovian...

  19. Non-Markovianity and reservoir memory of quantum channels: a quantum information theory perspective.

    Science.gov (United States)

    Bylicka, B; Chruściński, D; Maniscalco, S

    2014-07-21

    Quantum technologies rely on the ability to coherently transfer information encoded in quantum states along quantum channels. Decoherence induced by the environment sets limits on the efficiency of any quantum-enhanced protocol. Generally, the longer a quantum channel is the worse its capacity is. We show that for non-Markovian quantum channels this is not always true: surprisingly the capacity of a longer channel can be greater than of a shorter one. We introduce a general theoretical framework linking non-Markovianity to the capacities of quantum channels and demonstrate how harnessing non-Markovianity may improve the efficiency of quantum information processing and communication.

  20. Dynamical role of system-environment correlations in non-Markovian dynamics

    CERN Document Server

    Mazzola, Laura; Modi, Kavan; Paternostro, Mauro

    2012-01-01

    We analyse the role played by system-environment correlations in the emergence of non-Markovian dynamics. By working within the framework developed in Breuer et al., Phys. Rev. Lett. 103, 210401 (2009), we unveil a fundamental connection between non-Markovian behaviour and dynamics of system-environment correlations. We derive an upper bound to the derivative of rate of change of the distinguishability between different states of the system that explicitly depends on the development and establishment of correlations between system and environment. We illustrate our results using a fully solvable spin-chain model, which allows us to gain insight on the mechanisms triggering non-Markovian evolution.

  1. Non-Markovianity and reservoir memory of quantum channels: a quantum information theory perspective

    Science.gov (United States)

    Bylicka, B.; Chruściński, D.; Maniscalco, S.

    2014-01-01

    Quantum technologies rely on the ability to coherently transfer information encoded in quantum states along quantum channels. Decoherence induced by the environment sets limits on the efficiency of any quantum-enhanced protocol. Generally, the longer a quantum channel is the worse its capacity is. We show that for non-Markovian quantum channels this is not always true: surprisingly the capacity of a longer channel can be greater than of a shorter one. We introduce a general theoretical framework linking non-Markovianity to the capacities of quantum channels and demonstrate how harnessing non-Markovianity may improve the efficiency of quantum information processing and communication. PMID:25043763

  2. Non-Markovian Quantum State Diffusion for Temperature-Dependent Linear Spectra of Light Harvesting Aggregates

    CERN Document Server

    Ritschel, Gerhard; Möbius, Sebastian; Strunz, Walter T; Eisfeld, Alexander

    2014-01-01

    Non-Markovian Quantum State Diffusion (NMQSD) has turned out to be an effective method to calculate excitonic properties of aggregates composed of organic chromophores, taking into account the strong coupling of electronic transitions to vibrational modes of the chromophores. In this paper we show how to calculate linear optical spectra at finite temperatures in an efficient way. To this end we map a finite temperature environment to the zero temperature case using the so-called thermofield method. The zero temperature case equations can then be solved efficiently by standard integrators. As an example we calculate absorption and circular dichroism spectra of a linear aggregate. The formalism developed can be applied to calculate arbitrary correlation functions.

  3. Non-Markovian Quantum Error Deterrence by Dynamical Decoupling in a General Environment

    CERN Document Server

    Shiokawa, K

    2005-01-01

    A dynamical decoupling scheme for the deterrence of errors in the non-Markovian (usually corresponding to low temperature, short time, and strong coupling) regimes suitable for qubits constructed out of a multilevel structure is studied. We use the effective spin-boson model (ESBM) introduced recently [K. Shiokawa and B. L. Hu, Phys. Rev. A70, 062106 (2004)] as a low temperature limit of the quantum Brownian oscillator model, where one can obtain exact solutions for a general environment with colored noises. In our decoupling scheme a train of pairs of strong pulses are used to evolve the interaction Hamiltonian instantaneously. Using this scheme we show that the dynamical decoupling method can suppress $1/f$ noise with slower and hence more accessible pulses than previously studied, but it still fails to decouple super-Ohmic types of environments.

  4. Work distribution for a particle moving in an optical trap and non-Markovian bath

    Indian Academy of Sciences (India)

    Alok Samanta; K Srinivasu; Swapan K Ghosh

    2009-09-01

    We propose a simple approach to derive an exact analytical expression of work distribution for a system consisting of a colloidal particle trapped in an optical harmonic potential well, which is being pulled at a constant velocity through a solution represented by a non-Markovian bath. The thermal environment is represented by a bath composed of an infinite set of harmonic oscillators, and a model Hamiltonian for the trapped colloidal particle is constructed by representing the interaction with the bathvia linear dissipative mechanism. We have studied the effects of pulling time, pulling speed, and the adiabatic limit. It is also observed that only at long time the total work is completely converted into dissipative work.

  5. Open system quantum dynamics with correlated initial states, not completely positive maps and non-Markovianity

    CERN Document Server

    Devi, A R Usha; Sudha,

    2010-01-01

    Dynamical A and B maps have been employed extensively by Sudarshan and co-workers to investigate open system evolution of quantum systems. A canonical structure of the A-map is introduced here. It is shown that this canonical A-map enables us to investigate if the dynamics is completely positive (CP) or non-completely positive (NCP) in an elegant way and hence, it subsumes the basic results on open system dynamics. Identifying memory effects in open system evolution is gaining increasing importance recently and here, a criterion of non-Markovianity, based on the relative entropy of the dynamical state is proposed. The relative entropy difference of the dynamical system serves as a complementary characterization - though not related directly - to the fidelity difference criterion proposed recently. Three typical examples of open system evolution of a qubit, prepared initially in a correlated state with another qubit (environment), and evolving jointly under a specific unitary dynamics - which corresponds to a ...

  6. Experimental measurement of non-Markovian dynamics and self-diffusion in a strongly coupled plasma

    CERN Document Server

    Strickler, T S; McQuillen, P; Daligault, J; Killian, T C

    2015-01-01

    We present a study of the collisional relaxation of ion velocities in a strongly coupled, ultracold neutral plasma on short timescales compared to the inverse collision rate. Non-exponential decay towards equilibrium for the average velocity of a tagged population of ions heralds non-Markovian dynamics and a breakdown of assumptions underlying standard kinetic theory. We prove the equivalence of the average-velocity curve to the velocity autocorrelation function, a fundamental statistical quantity that provides access to equilibrium transport coefficients and aspects of individual particle trajectories in a regime where experimental measurements have been lacking. From our data, we calculate the ion self-diffusion constant. This demonstrates the utility of ultracold neutral plasmas for isolating the effects of strong coupling on collisional processes, which is of interest for dense laboratory and astrophysical plasmas.

  7. Non-Markovian Model for Transport and Reactions of Particles in Spiny Dendrites

    Science.gov (United States)

    Fedotov, Sergei; Méndez, Vicenç

    2008-11-01

    Motivated by the experiments [Santamaria , Neuron 52, 635 (2006)NERNET0896-627310.1016/j.neuron.2006.10.025] that indicated the possibility of subdiffusive transport of molecules along dendrites of cerebellar Purkinje cells, we develop a mesoscopic model for transport and chemical reactions of particles in spiny dendrites. The communication between spines and a parent dendrite is described by a non-Markovian random process and, as a result, the overall movement of particles can be subdiffusive. A system of integrodifferential equations is derived for the particles densities in dendrites and spines. This system involves the spine-dendrite interaction term which describes the memory effects and nonlocality in space. We consider the impact of power-law waiting time distributions on the transport of biochemical signals and mechanism of the accumulation of plasticity-inducing signals inside spines.

  8. Connecting two jumplike unravelings for non-Markovian open quantum systems

    CERN Document Server

    Luoma, Kimmo; Piilo, Jyrki

    2011-01-01

    The development and use of Monte Carlo algorithms plays a visible role in the study of non-Markovian quantum dynamics due to the provided insight and powerful numerical methods for solving the system dynamics. In the Markovian case, the connections between the various types of methods are fairly well-understood while for non-Markovian case there has so far been only a few studies. We focus here on two jumplike unravelings of non-Markovian dynamics, the non-Markovian quantum jump (NMQJ) method and the property state method by Gambetta, Askerud, and Wiseman (GAW). The results for simple quantum optical systems illustrate the connections between the realizations of the two methods and also highlight how the probability currents between the system and environment, or between the property states of the total system, associate to the decay rates of time-local master equations, and consequently to the jump rates of the NMQJ method.

  9. A framework for the direct evaluation of large deviations in non-Markovian processes

    Science.gov (United States)

    Cavallaro, Massimo; Harris, Rosemary J.

    2016-11-01

    We propose a general framework to simulate stochastic trajectories with arbitrarily long memory dependence and efficiently evaluate large deviation functions associated to time-extensive observables. This extends the ‘cloning’ procedure of Giardiná et al (2006 Phys. Rev. Lett. 96 120603) to non-Markovian systems. We demonstrate the validity of this method by testing non-Markovian variants of an ion-channel model and the totally asymmetric exclusion process, recovering results obtainable by other means.

  10. Non-Markovian dissipative quantum mechanics with stochastic trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Werner

    2010-09-09

    All fields of physics - be it nuclear, atomic and molecular, solid state, or optical - offer examples of systems which are strongly influenced by the environment of the actual system under investigation. The scope of what is called ''the environment'' may vary, i.e., how far from the system of interest an interaction between the two does persist. Typically, however, it is much larger than the open system itself. Hence, a fully quantum mechanical treatment of the combined system without approximations and without limitations of the type of system is currently out of reach. With the single assumption of the environment to consist of an internally thermalized set of infinitely many harmonic oscillators, the seminal work of Stockburger and Grabert [Chem. Phys., 268:249-256, 2001] introduced an open system description that captures the environmental influence by means of a stochastic driving of the reduced system. The resulting stochastic Liouville-von Neumann equation describes the full non-Markovian dynamics without explicit memory but instead accounts for it implicitly through the correlations of the complex-valued noise forces. The present thesis provides a first application of the Stockburger-Grabert stochastic Liouville-von Neumann equation to the computation of the dynamics of anharmonic, continuous open systems. In particular, it is demonstrated that trajectory based propagators allow for the construction of a numerically stable propagation scheme. With this approach it becomes possible to achieve the tremendous increase of the noise sample count necessary to stochastically converge the results when investigating such systems with continuous variables. After a test against available analytic results for the dissipative harmonic oscillator, the approach is subsequently applied to the analysis of two different realistic, physical systems. As a first example, the dynamics of a dissipative molecular oscillator is investigated. Long time

  11. Non-Markovian Persistence at the PC point of a 1d non-equilibrium kinetic Ising model

    CERN Document Server

    Menyhard, N; Menyhard, Nora; Odor, Geza

    1997-01-01

    One-dimensional non-equilibrium kinetic Ising models evolving under the competing effect of spin flips at zero temperature and nearest neighbour spin exchanges exhibiting a parity-conserving (PC) phase transition on the level of kinks are investigated here numerically from the point of view of the underlying spin system. The dynamical persistency exponent $\\Theta$ and the exponent $lambda$ characterising the two-time autocorrelation function of the total magnetization under non-equilibrium conditions are reported. It is found that the PC transition has strong effect: the process becomes non-Markovian and the above exponents exhibit drastic changes as compared to the Glauber-Ising case.

  12. Quantum Discord Dynamics in Two Different Non-Markovian Reservoirs

    Institute of Scientific and Technical Information of China (English)

    DING Bang-Fu; WANG Xiao-Yun; LIU Jing-Feng; YAN Lin; ZHAO He-Ping

    2011-01-01

    The quantum discord dynamics of two non-coupled two-level atoms independently interacting with their reservoir is studied under two kinds of non-Markovian conditions,namely,an off-resonant case with atomic transition frequency and a photonic band gap.In the first case,the phenomenon of the quantum discord loss and the oscillatory behavior of the quantum discord can occur by changing the detuning quantity and reducing the spectral coupling width for any initial Bell state.Under the second condition,the trapping phenomenon of the quantum discord can be presented by adjusting the width of gap,that is,the quantum discord of two atoms keep a nonzero constant for a long time.Entanglement,as a kind of quantum correlation without a classical counterpart,plays an important role in quantum information and communication theory,[1,2] quantum teleportation,[3] quantum cryptography[4,5] and universal quantum computing.[6]%We report the first implementation of transparent electrodes in bottom-gate graphene transistors used for photo detection. Compared to conventional nontransparent electrodes, the transparent electrodes allow photons to transmit through to the graphene beneath, providing an enlarged absorption area and thereby giving rise to an enhancement of photocurrent generation. The devices are fabricated with an asymmetric metallization scheme and the experimental results show that the maximum photocurrent density using the transparent electrodes (ITO and Pd/ITO) is over two times higher than that using the nontransparent electrodes (Ti and Pd), indicating a significant enhancement in the performance of graphene photo sensors.

  13. A non-Markovian model of rill erosion

    Science.gov (United States)

    Winter, C.; Damron, M.

    2009-12-01

    Stochastic processes with reinforcement are inherently non-Markovian and therefore may model geophysical processes with memory, for instance patterns of rill erosion, more realistically than Markovian models. Reinforcement provides a bias to a system that is equivalent to infinite memory, making a system more likely to occupy a given state the more often the state is visited. Some well-studied examples in applied mathematics include variations on the urn of P'olya and reinforced random walks. Many natural phenomena exhibit similar behavior: for instance, an overall pattern of rills is relatively stable once it is established, although small details of the pattern may change frequently and catastrophes that permanently alter it may occasionally occur. To model the phenomenology of rill erosion, we propose a simple discrete time, infinite-memory random process defined on the nodes and edges of an oriented diagonal lattice. Lattice models have often been used to investigate the morphology of natural drainage networks, but our focus is as much on the dynamics of network formation as it is on morphology. The lattice in our model starts out smooth in the sense that it has no edges initially, but it sprouts edges everywhere the instant the process starts, much as rain can start soil erosion everywhere on a hillslope at once. Exactly one edge (rill segment) descends from each node, and it points either left or right. Sediment loads travel along networks of edges and are accumulated at nodes. At every node and at every time step, a simple two parameter reinforcing law randomly determines the direction of the node’s output and then is updated. The degree of reinforcement is set by comparing the node's current sediment load to the load history of the entire network above it and is governed by two system parameters representing respectively rainfall intensity and the soil’s resistance to change. The current pattern of connections among nodes represents the present state of

  14. Non-Markovian reduced dynamics of ultrafast charge transfer at an oligothiophene–fullerene heterojunction

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Keith H., E-mail: keith.hughes@bangor.ac.uk [School of Chemistry, Bangor University, Bangor, Gwynedd LL57 2UW (United Kingdom); Cahier, Benjamin [School of Chemistry, Bangor University, Bangor, Gwynedd LL57 2UW (United Kingdom); Martinazzo, Rocco [Dipartimento di Chimica Università degli Studi di Milano, v. Golgi 19, 20133 Milano (Italy); Tamura, Hiroyuki [WPI-Advanced Institute for Material Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Burghardt, Irene [Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/Main (Germany)

    2014-10-17

    Highlights: • Quantum dynamical study of exciton dissociation at a heterojunction interface. • The non-Markovian quantum dynamics involves a highly structured spectral density. • Spectral density is reconstructed from an effective mode transformation of the Hamiltonian. • The dynamics is studied using the hierarchical equations of motion approach. • It was found that the temperature has little effect on the charge transfer. - Abstract: We extend our recent quantum dynamical study of the exciton dissociation and charge transfer at an oligothiophene–fullerene heterojunction interface (Tamura et al., 2012) [6] by investigating the process using the non-perturbative hierarchical equations of motion (HEOM) approach. Based upon an effective mode reconstruction of the spectral density the effect of temperature on the charge transfer is studied using reduced density matrices. It was found that the temperature had little effect on the charge transfer and a coherent dynamics persists over the first few tens of femtoseconds, indicating that the primary charge transfer step proceeds by an activationless pathway.

  15. Unification of witnessing initial system-environment correlations and witnessing non-Markovianity

    CERN Document Server

    Rodríguez-Rosario, César A; Mazzola, Laura; Aspuru-Guzik, Alán

    2012-01-01

    We show the connection between a witness that detects dynamical maps with initial system-environment correlations and a witness that detects non-Markovian open quantum systems. Our analysis is based on studying the role that state preparation plays in witnessing violations of contractivity of open quantum system dynamics. Contractivity is a property of some quantum processes where the trace distance of density matrices decrease with time. From this, we show how a witness of initial-correlations is an upper bound to a witness of non-Markovianity. We discuss how this relationship shows further connections between initial system-environment correlations and non-Markovianity at an instance of time in open quantum systems.

  16. Equivalence of the measures of non-Markovianity for open two-level systems

    Energy Technology Data Exchange (ETDEWEB)

    Zeng Haosheng; Tang Ning; Zheng Yanping; Wang Guoyou [Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Department of Physics, Hunan Normal University, Changsha 410081 (China)

    2011-09-15

    Different measures have been presented to depict the deviation of quantum time evolution in open systems from Markovian processes. We demonstrate that the measure proposed by Breuer, Laine, and Piilo [Phys. Rev. Lett. 103, 210401 (2009)] and the two measures proposed by Rivas, Huelga, and Plenio [Phys. Rev. Lett. 105, 050403 (2010)] have exactly the same non-Markovian time-evolution intervals and thus are really equivalent to each other when they are applied to open two-level systems coupled to environments via the Jaynes-Cummings or dephasing models. This equivalence implies that the three measures, in different ways, capture the intrinsic character of the non-Markovianity of quantum evolutional processes. We also show that the maximization in the definition of the first measure can be actually removed for the considered models without influencing the sensibility of the measure to detect non-Markovianity.

  17. Dynamics of interacting qubits coupled to a common bath: Non-Markovian quantum state diffusion approach

    CERN Document Server

    Zhao, Xinyu; Corn, Brittany; Yu, Ting; 10.1103/PhysRevA.84.032101

    2011-01-01

    Non-Markovian dynamics is studied for two interacting quibts strongly coupled to a dissipative bosonic environment. For the first time, we have derived the non-Markovian quantum state diffusion (QSD) equation for the coupled two-qubit system without any approximations, and in particular, without the Markov approximation. As an application and illustration of our derived time-local QSD equation, we investigate the temporal behavior of quantum coherence dynamics. In particular, we find a strongly non-Markovian regime where entanglement generation is significantly modulated by the environmental memory. Additionally, we studied the residual entanglement in the steady state by analyzing the steady state solution of the QSD equation. Finally, we have discussed an approximate QSD equation.

  18. Non-Markovian Quantum Evolution: Time-Local Generators and Memory Kernels

    Science.gov (United States)

    Chruściński, Dariusz; Należyty, Paweł

    2016-06-01

    In this paper we provide a basic introduction to the topic of quantum non-Markovian evolution presenting both time-local and memory kernel approach to the evolution of open quantum systems. We start with the standard notion of a classical Markovian stochastic process and generalize it to classical Markovian stochastic evolution which in turn becomes a starting point of the quantum setting. Our approach is based on the notion of P-divisible, CP-divisible maps and their refinements to k-divisible maps. Basic methods enabling one to detect non-Markovianity of the quantum evolution are also presented. Our analysis is illustrated by several simple examples.

  19. Optical signatures of non-Markovian behavior in open quantum systems

    DEFF Research Database (Denmark)

    McCutcheon, Dara

    2016-01-01

    for the correlation functions, making only a second-order expansion in the system-environment coupling strength and invoking the Born approximation at a fixed initial time. The results are used to investigate a driven semiconductor quantum dot coupled to an acoustic phonon bath, where we find the non-Markovian nature......We derive an extension to the quantum regression theorem which facilitates the calculation of two-time correlation functions and emission spectra for systems undergoing non-Markovian evolution. The derivation exploits projection operator techniques, with which we obtain explicit equations of motion...

  20. Non-Markovian dynamics in pulsed and continuous wave atom lasers

    CERN Document Server

    Breuer, H P; Kappler, B; Petruccione, F

    1999-01-01

    The dynamics of atom lasers with a continuous output coupler based on two-photon Raman transitions is investigated. With the help of the time-convolutionless projection operator technique the quantum master equations for pulsed and continuous wave (cw) atom lasers are derived. In the case of the pulsed atom laser the power of the time-convolutionless projection operator technique is demonstrated through comparison with the exact solution. It is shown that in an intermediate coupling regime where the Born-Markov approximation fails the results of this algorithm agree with the exact solution. To study the dynamics of a continuous wave atom laser a pump mechanism is included in the model. Whereas the pump mechanism is treated within the Born-Markov approximation, the output coupling leads to non-Markovian effects. The solution of the master equation resulting from the time-convolutionless projection operator technique exhibits strong oscillations in the occupation number of the Bose-Einstein condensate. These os...

  1. Error Distributions on Large Entangled States with Non-Markovian Dynamics

    DEFF Research Database (Denmark)

    McCutcheon, Dara; Lindner, Netanel H.; Rudolph, Terry

    2014-01-01

    We investigate the distribution of errors on a computationally useful entangled state generated via the repeated emission from an emitter undergoing strongly non-Markovian evolution. For emitter-environment coupling of pure-dephasing form, we show that the probability that a particular patten of ...

  2. Observation of Non-Markovian Dynamics of a Single Quantum Dot in a Micropillar Cavity

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg; Ates, Serkan; Lund-Hansen, Toke;

    2011-01-01

    We measure the detuning-dependent dynamics of a quasiresonantly excited single quantum dot coupled to a micropillar cavity. The system is modeled with the dissipative Jaynes-Cummings model where all experimental parameters are determined by explicit measurements. We observe non-Markovian dynamics...

  3. Non-Markovian dynamics in the theory of full counting statistics

    DEFF Research Database (Denmark)

    Flindt, Christian; Braggio, A.; Novotny, Tomas

    2007-01-01

    generating function corresponding to the resulting non-Markovian rate equation and find that the measured current cumulants behave significantly differently compared to those of a Markovian transport process. Our findings provide a novel interpretation of noise suppression found in a number of systems....

  4. Non-markovianity and CHSH-Bell inequality violation in multipartite dissipative systems

    CERN Document Server

    Thilagam, A

    2012-01-01

    We examine the non-Markovian dynamics in a multipartite system of two initially correlated atomic qubits, each located in a single-mode leaky cavity and interacting with its own bosonic reservoir. We show the dominance of non-Markovian features, as quantified by the difference in fidelity of the evolved system with its density matrix at an earlier time, in three specific two-qubit partitions associated with the cavity-cavity and atom-reservoir density matrices within the same subsystem, and the cavity-reservoir reduced matrix across the two subsystems. The non-Markovianity in the cavity-cavity subsystem is seen to be optimized in the vicinity of the exceptional point. The CHSH-Bell inequality computed for various two-qubit partitions show that high non-locality present in a specific subsystem appears in conjunction with enhanced non-Markovian dynamics in adjacent subsystems. This is in contrast to the matching existence of non-locality and quantum correlations in regions spanned by time t and the cavity decay...

  5. Mode suppression in the non-Markovian limit by time-gated stimulated photon echo

    NARCIS (Netherlands)

    de Boeij, W.P.; Pshenichnikov, M.S; Wiersma, D. A.

    1996-01-01

    It is demonstrated that enhanced mode suppression in stimulated photon echo experiments can be obtained by diagonal time gating of the echo. This technique is especially important when the optical dynamics of the system is non-Markovian. A two-mode Brownian oscillator model is used to analyze the ef

  6. Non-Markovian closure models for large eddy simulations using the Mori-Zwanzig formalism

    Science.gov (United States)

    Parish, Eric J.; Duraisamy, Karthik

    2017-01-01

    This work uses the Mori-Zwanzig (M-Z) formalism, a concept originating from nonequilibrium statistical mechanics, as a basis for the development of coarse-grained models of turbulence. The mechanics of the generalized Langevin equation (GLE) are considered, and insight gained from the orthogonal dynamics equation is used as a starting point for model development. A class of subgrid models is considered which represent nonlocal behavior via a finite memory approximation [Stinis, arXiv:1211.4285 (2012)], the length of which is determined using a heuristic that is related to the spectral radius of the Jacobian of the resolved variables. The resulting models are intimately tied to the underlying numerical resolution and are capable of approximating non-Markovian effects. Numerical experiments on the Burgers equation demonstrate that the M-Z-based models can accurately predict the temporal evolution of the total kinetic energy and the total dissipation rate at varying mesh resolutions. The trajectory of each resolved mode in phase space is accurately predicted for cases where the coarse graining is moderate. Large eddy simulations (LESs) of homogeneous isotropic turbulence and the Taylor-Green Vortex show that the M-Z-based models are able to provide excellent predictions, accurately capturing the subgrid contribution to energy transfer. Last, LESs of fully developed channel flow demonstrate the applicability of M-Z-based models to nondecaying problems. It is notable that the form of the closure is not imposed by the modeler, but is rather derived from the mathematics of the coarse graining, highlighting the potential of M-Z-based techniques to define LES closures.

  7. Non-Markovian dynamics, decoherence and entanglement in dissipative quantum systems with applications to quantum information theory of continuous variable systems; Nicht-Markovsche Dynamik, Dekohaerenz und Verschraenkung in dissipativen Quantensystemen mit Anwendung in der Quanteninformationstheorie von Systemen kontinuierlicher Variablen

    Energy Technology Data Exchange (ETDEWEB)

    Hoerhammer, C.

    2007-11-26

    In this thesis, non-Markovian dynamics, decoherence and entanglement in dissipative quantum systems are studied. In particular, applications to quantum information theory of continuous variable systems are considered. The non-Markovian dynamics are described by the Hu-Paz-Zhang master equation of quantum Brownian motion. In this context the focus is on non-Markovian effects on decoherence and separability time scales of various single- mode and two-mode continuous variable states. It is verified that moderate non-Markovian influences slow down the decay of interference fringes and quantum correlations, while strong non-Markovian effects resulting from an out-of-resonance bath can even accelerate the loss of coherence, compared to predictions of Markovian approximations. Qualitatively different scenarios including exponential, Gaussian or algebraic decay of the decoherence function are analyzed. It is shown that partial recurrence of coherence can occur in case of non-Lindblad-type dynamics. The time evolution of quantum correlations of entangled two-mode continuous variable states is examined in single-reservoir and two-reservoir models, representing noisy correlated or uncorrelated non-Markovian quantum channels. For this purpose the model of quantum Brownian motion is extended. Various separability criteria for Gaussian and non-Gaussian continuous variable systems are applied. In both types of reservoir models moderate non-Markovian effects prolong the separability time scales. However, in these models the properties of the stationary state may differ. In the two-reservoir model the initial entanglement is completely lost and both modes are finally uncorrelated. In a common reservoir both modes interact indirectly via the coupling to the same bath variables. Therefore, new quantum correlations may emerge between the two modes. Below a critical bath temperature entanglement is preserved even in the steady state. A separability criterion is derived, which depends

  8. Learning from history: Non-Markovian analyses of complex trajectories for extracting long-time behavior

    CERN Document Server

    Suarez, Ernesto

    2014-01-01

    A number of modern sampling methods probe long time behavior in complex biomolecules using a set of relatively short trajectory segments. Markov state models (MSMs) can be useful in analyzing such data sets, but in particularly complex landscapes, the available trajectory data may prove insufficient for constructing valid Markov models. Here, we explore the potential utility of history-dependent analyses applied to relatively poor decompositions of configuration space for which MSMs are inadequate. Our approaches build on previous work [Suarez et. al., JCTC 2014] showing that, with sufficient history information, unbiased equilibrium and non-equilibrium observables can be obtained even for arbitrary non-Markovian divisions of phase space. We explore a range of non-Markovian approximations using varying amounts of history information to model the finite length of trajectory segments, applying the analyses to toy models as well as several proteins previously studied by microsec-milisec scale atomistic simulatio...

  9. Solving non-Markovian open quantum systems with multi-channel reservoir coupling

    CERN Document Server

    Broadbent, Curtis J; Yu, Ting; Eberly, Joseph H

    2011-01-01

    We extend the non-Markovian quantum state diffusion (QSD) equation to open quantum systems which exhibit multi-channel coupling to a harmonic oscillator reservoir. Open quantum systems which have multi-channel reservoir coupling are those in which canonical transformation of reservoir modes cannot reduce the number of reservoir operators appearing in the interaction Hamiltonian to one. We show that the non-Markovian QSD equation for multi-channel reservoir coupling can, in some cases, lead to an exact master equation which we derive. We then derive the exact master equation for the three-level system in a vee-type configuration which has multi-channel reservoir coupling and give the analytical solution. Finally, we examine the evolution of the three-level vee-type system with generalized Ornstein-Uhlenbeck reservoir correlations numerically.

  10. Solving non-Markovian open quantum systems with multi-channel reservoir coupling

    Science.gov (United States)

    Broadbent, Curtis J.; Jing, Jun; Yu, Ting; Eberly, Joseph H.

    2012-08-01

    We extend the non-Markovian quantum state diffusion (QSD) equation to open quantum systems which exhibit multi-channel coupling to a harmonic oscillator reservoir. Open quantum systems which have multi-channel reservoir coupling are those in which canonical transformation of reservoir modes cannot reduce the number of reservoir operators appearing in the interaction Hamiltonian to one. We show that the non-Markovian QSD equation for multi-channel reservoir coupling can, in some cases, lead to an exact master equation which we derive. We then derive the exact master equation for the three-level system in a vee-type configuration which has multi-channel reservoir coupling and give the analytical solution. Finally, we examine the evolution of the three-level vee-type system with generalized Ornstein-Uhlenbeck reservoir correlations numerically.

  11. Violation of the scaling relation and non-Markovian nature of earthquake aftershocks

    CERN Document Server

    Abe, Sumiyoshi

    2008-01-01

    The statistical properties of earthquake aftershocks are studied. The scaling relation for the exponents of the Omori law and the power-law calm time distribution (i.e., the interoccurrence time distribution), which is valid if a sequence of aftershocks is a singular Markovian process, is carefully examined. Data analysis shows significant violation of the scaling relation, implying the non-Markovian nature of aftershocks.

  12. Vibrational mode suppression in the non-Markovian limit : Diagonal time-gating of the stimulated photon echo

    NARCIS (Netherlands)

    De Boeij, W. P.; Pshenichnikov, M. S.; Wiersma, D. A.

    1996-01-01

    We demonstrate a novel technique for efficient vibrational mode suppression in stimulated photon echo by diagonal time-gating. This is especially important if the system exhibits non-Markovian optical dynamics.

  13. Solving non-Markovian open quantum systems with multi-channel reservoir coupling

    Energy Technology Data Exchange (ETDEWEB)

    Broadbent, Curtis J., E-mail: curtis.broadbent@rochester.edu [Rochester Theory Center, and Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States); Jing, Jun; Yu, Ting [Center for Controlled Quantum Systems, and the Department of Physics and Engineering Physics, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Eberly, Joseph H. [Rochester Theory Center, and Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States)

    2012-08-15

    We extend the non-Markovian quantum state diffusion (QSD) equation to open quantum systems which exhibit multi-channel coupling to a harmonic oscillator reservoir. Open quantum systems which have multi-channel reservoir coupling are those in which canonical transformation of reservoir modes cannot reduce the number of reservoir operators appearing in the interaction Hamiltonian to one. We show that the non-Markovian QSD equation for multi-channel reservoir coupling can, in some cases, lead to an exact master equation which we derive. We then derive the exact master equation for the three-level system in a vee-type configuration which has multi-channel reservoir coupling and give the analytical solution. Finally, we examine the evolution of the three-level vee-type system with generalized Ornstein-Uhlenbeck reservoir correlations numerically. - Highlights: Black-Right-Pointing-Pointer The concept of multi-channel vs. single-channel reservoir coupling is rigorously defined. Black-Right-Pointing-Pointer The non-Markovian quantum state diffusion equation for arbitrary multi-channel reservoir coupling is derived. Black-Right-Pointing-Pointer An exact time-local master equation is derived under certain conditions. Black-Right-Pointing-Pointer The analytical solution to the three-level system in a vee-type configuration is found. Black-Right-Pointing-Pointer The evolution of the three-level system under generalized Ornstein-Uhlenbeck noise is plotted for many parameter regimes.

  14. Equivalence of the measures of non-Markovianity for open two-level systems

    Science.gov (United States)

    Zeng, Hao-Sheng; Tang, Ning; Zheng, Yan-Ping; Wang, Guo-You

    2011-09-01

    Different measures have been presented to depict the deviation of quantum time evolution in open systems from Markovian processes. We demonstrate that the measure proposed by Breuer, Laine, and Piilo [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.103.210401 103, 210401 (2009)] and the two measures proposed by Rivas, Huelga, and Plenio [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.105.050403 105, 050403 (2010)] have exactly the same non-Markovian time-evolution intervals and thus are really equivalent to each other when they are applied to open two-level systems coupled to environments via the Jaynes-Cummings or dephasing models. This equivalence implies that the three measures, in different ways, capture the intrinsic character of the non-Markovianity of quantum evolutional processes. We also show that the maximization in the definition of the first measure can be actually removed for the considered models without influencing the sensibility of the measure to detect non-Markovianity.

  15. Non-Markovian linear response theory for quantum open systems and its applications.

    Science.gov (United States)

    Shen, H Z; Li, D X; Yi, X X

    2017-01-01

    The Kubo formula is an equation that expresses the linear response of an observable due to a time-dependent perturbation. It has been extended from closed systems to open systems in recent years under the Markovian approximation, but is barely explored for open systems in non-Markovian regimes. In this paper, we derive a formula for the linear response of an open system to a time-independent external field. This response formula is available for both Markovian and non-Markovian dynamics depending on parameters in the spectral density of the environment. As an illustration of the theory, the Hall conductance of a two-band system subjected to environments is derived and discussed. With the tight-binding model, we point out the Hall conductance changes from Markovian to non-Markovian dynamics by modulating the spectral density of the environment. Our results suggest a way to the controlling of the system response, which has potential applications for quantum statistical mechanics and condensed matter physics.

  16. Exact master equation for a spin interacting with a spin bath: Non-Markovianity and negative entropy production rate

    Science.gov (United States)

    Bhattacharya, Samyadeb; Misra, Avijit; Mukhopadhyay, Chiranjib; Pati, Arun Kumar

    2017-01-01

    An exact canonical master equation of the Lindblad form is derived for a central spin interacting uniformly with a sea of completely unpolarized spins. The Kraus operators for the dynamical map are also derived. The non-Markovianity of the dynamics in terms of the divisibility breaking of the dynamical map and the increase of the trace distance fidelity between quantum states is shown. Moreover, it is observed that the irreversible entropy production rate is always negative (for a fixed initial state) whenever the dynamics exhibits non-Markovian behavior. In continuation with the study of witnessing non-Markovianity, it is shown that the positive rate of change of the purity of the central qubit is a faithful indicator of the non-Markovian information backflow. Given the experimental feasibility of measuring the purity of a quantum state, a possibility of experimental demonstration of non-Markovianity and the negative irreversible entropy production rate is addressed. This gives the present work considerable practical importance for detecting the non-Markovianity and the negative irreversible entropy production rate.

  17. Exact non-Markovian master equation for the spin-boson and Jaynes-Cummings models

    Science.gov (United States)

    Ferialdi, L.

    2017-02-01

    We provide the exact non-Markovian master equation for a two-level system interacting with a thermal bosonic bath, and we write the solution of such a master equation in terms of the Bloch vector. We show that previous approximated results are particular limits of our exact master equation. We generalize these results to more complex systems involving an arbitrary number of two-level systems coupled to different thermal baths, providing the exact master equations also for these systems. As an example of this general case we derive the master equation for the Jaynes-Cummings model.

  18. Non-Markovian random walks and nonlinear reactions: Subdiffusion and propagating fronts

    Science.gov (United States)

    Fedotov, Sergei

    2010-01-01

    The main aim of the paper is to incorporate the nonlinear kinetic term into non-Markovian transport equations described by a continuous time random walk (CTRW) with nonexponential waiting time distributions. We consider three different CTRW models with reactions. We derive nonlinear Master equations for the mesoscopic density of reacting particles corresponding to CTRW with arbitrary jump and waiting time distributions. We apply these equations to the problem of front propagation in the reaction-transport systems with Kolmogorov-Petrovskii-Piskunov kinetics and anomalous diffusion. We have found an explicit expression for the speed of a propagating front in the case of subdiffusive transport.

  19. Non-Markovian spin-resolved counting statistics and an anomalous relation between autocorrelations and cross correlations in a three-terminal quantum dot

    Science.gov (United States)

    Luo, JunYan; Yan, Yiying; Huang, Yixiao; Yu, Li; He, Xiao-Ling; Jiao, HuJun

    2017-01-01

    We investigate the noise correlations of spin and charge currents through an electron spin resonance (ESR)-pumped quantum dot, which is tunnel coupled to three electrodes maintained at an equivalent chemical potential. A recursive scheme is employed with inclusion of the spin degrees of freedom to account for the spin-resolved counting statistics in the presence of non-Markovian effects due to coupling with a dissipative heat bath. For symmetric spin-up and spin-down tunneling rates, an ESR-induced spin flip mechanism generates a pure spin current without an accompanying net charge current. The stochastic tunneling of spin carriers, however, produces universal shot noises of both charge and spin currents, revealing the effective charge and spin units of quasiparticles in transport. In the case of very asymmetric tunneling rates for opposite spins, an anomalous relationship between noise autocorrelations and cross correlations is revealed, where super-Poissonian autocorrelation is observed in spite of a negative cross correlation. Remarkably, with strong dissipation strength, non-Markovian memory effects give rise to a positive cross correlation of the charge current in the absence of a super-Poissonian autocorrelation. These unique noise features may offer essential methods for exploiting internal spin dynamics and various quasiparticle tunneling processes in mesoscopic transport.

  20. Non-Markovian spiking statistics of a neuron with delayed feedback in presence of refractoriness.

    Science.gov (United States)

    Kravchuk, Kseniia; Vidybida, Alexander

    2014-02-01

    Spiking statistics of a self-inhibitory neuron is considered. The neuron receives excitatory input from a Poisson stream and inhibitory impulses through a feedback line with a delay. After triggering, the neuron is in the refractory state for a positive period of time. Recently, [35,6], it was proven for a neuron with delayed feedback and without the refractory state, that the output stream of interspike intervals (ISI) cannot be represented as a Markov process. The refractory state presence, in a sense limits the memory range in the spiking process, which might restore Markov property to the ISI stream. Here we check such a possibility. For this purpose, we calculate the conditional probability density P (tn+1 l tn,...,t1,t0), and prove exactly that it does not reduce to P (tn+1 l tn,...,t1) for any n ⋝0. That means, that activity of the system with refractory state as well cannot be represented as a Markov process of any order. We conclude that it is namely the delayed feedback presence which results in non-Markovian statistics of neuronal firing. As delayed feedback lines are common for any realistic neural network, the non-Markovian statistics of the network activity should be taken into account in processing of experimental data.

  1. Non-Markovian transmission through two quantum dots connected by a continuum

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Yunshan [School of Physics, Peking University, Beijing 100871 (China); Department of Physics, Beijing Normal University, Beijing 100875 (China); Xu, Luting; Meng, Jianyu [Department of Physics, Beijing Normal University, Beijing 100875 (China); Li, Xin-Qi, E-mail: lixinqi@bnu.edu.cn [Department of Physics, Beijing Normal University, Beijing 100875 (China)

    2012-10-01

    We consider a transport setup that contains a double-dot connected by a continuum. Via an exact solution of the time-dependent Schrödinger equation, we demonstrate a highly non-Markovian quantum-coherence-mediated transport through this dot–continuum–dot (DCD) system, which is in contrast with the common premise since in typical case a quantum particle does not reenter the system of interest once it irreversibly decayed into a continuum (such as the spontaneous emission of a photon). We also find that this DCD system supports an unusual steady state with unequal source and drain currents, owing to electrons irreversibly entering the continuum and floating there. -- Highlights: ► We analyze the non-Markovian transmission through a double-dot connected by a continuum. ► We convert the many-electron problem into a single-particle approach and find an exact solution. ► We reveal some interesting behaviors associated with quantum-coherence-assisted transmission through a continuum.

  2. Nonequilibrium thermodynamics in the strong coupling and non-Markovian regime based on a reaction coordinate mapping

    Science.gov (United States)

    Strasberg, Philipp; Schaller, Gernot; Lambert, Neill; Brandes, Tobias

    2016-07-01

    We propose a method to study the thermodynamic behaviour of small systems beyond the weak coupling and Markovian approximation, which is different in spirit from conventional approaches. The idea is to redefine the system and environment such that the effective, redefined system is again coupled weakly to Markovian residual baths and thus, allows to derive a consistent thermodynamic framework for this new system-environment partition. To achieve this goal we make use of the reaction coordinate (RC) mapping, which is a general method in the sense that it can be applied to an arbitrary (quantum or classical and even time-dependent) system coupled linearly to an arbitrary number of harmonic oscillator reservoirs. The core of the method relies on an appropriate identification of a part of the environment (the RC), which is subsequently included as a part of the system. We demonstrate the power of this concept by showing that non-Markovian effects can significantly enhance the steady state efficiency of a three-level-maser heat engine, even in the regime of weak system-bath coupling. Furthermore, we show for a single electron transistor coupled to vibrations that our method allows one to justify master equations derived in a polaron transformed reference frame.

  3. Suppressing non-Markovian noises by coupling the qubit to a chaotic device

    CERN Document Server

    Zhang, Jing; Zhang, Wei-Min; Wu, Re-Bing; Tarn, Tzyh-Jong

    2011-01-01

    To suppress decoherence of solid-state qubits which are coupled to the non-Markovian noises, we propose a strategy to couple the qubit with a chaotic device, of which the broad power distribution in the high-frequency domain can be used to freeze the noises just like the dynamical decoupling control (DDC) method. Compared with the DDC, high-frequency components can be generated by the chaotic device even driven by a low-frequency field and we do not need to optimize the control fields to generate complex control pulses. As an application to superconducting circuits, we find that various noises in a wide frequency domain, including low-frequency $1/f$, high-frequency Ohmic, sub-Ohmic, and super-Ohmic noises, can be efficiently suppressed by coupling the qubit to a Duffing oscillator, and the decoherence rate of the qubit is efficiently decreased for about $100$ times in magnitude.

  4. Analysis of non-Markovian coupling of a lattice-trapped atom to free space

    Science.gov (United States)

    Stewart, Michael; Krinner, Ludwig; Pazmiño, Arturo; Schneble, Dominik

    2017-01-01

    Behavior analogous to that of spontaneous emission in photonic band-gap materials has been predicted for an atom-optical system consisting of an atom confined in a well of a state-dependent optical lattice that is coupled to free space through an internal-state transition [de Vega et al., Phys. Rev. Lett. 101, 260404 (2008), 10.1103/PhysRevLett.101.260404]. Using the Weisskopf-Wigner approach and considering a one-dimensional geometry, we analyze the properties of this system in detail, including the evolution of the lattice-trapped population, the momentum distribution of emitted matter waves, and the detailed structure of an evanescent matter-wave state below the continuum boundary. We compare and contrast our findings for the transition from Markovian to non-Markovian behaviors to those previously obtained for three dimensions.

  5. Non-Markovian Brownian motion in a magnetic field and time-dependent force fields

    Science.gov (United States)

    Hidalgo-Gonzalez, J. C.; Jiménez-Aquino, J. I.; Romero-Bastida, M.

    2016-11-01

    This work focuses on the derivation of the velocity and phase-space generalized Fokker-Planck equations for a Brownian charged particle embedded in a memory thermal bath and under the action of force fields: a constant magnetic field and arbitrary time-dependent force fields. To achieve the aforementioned goal we use a Gaussian but non-Markovian generalized Langevin equation with an arbitrary friction memory kernel. In a similar way, the generalized diffusion equation in the zero inertia limit is also derived. Additionally we show, in the absence of the time-dependent external forces, that, if the fluctuation-dissipation relation of the second kind is valid, then the generalized Langevin dynamics associated with the charged particle reaches a stationary state in the large-time limit. The consistency of our theoretical results is also verified when they are compared with those derived in the absence of the force fields and in the Markovian case.

  6. Dynamics and protection of entanglement in n -qubit systems within Markovian and non-Markovian environments

    Science.gov (United States)

    Nourmandipour, A.; Tavassoly, M. K.; Rafiee, M.

    2016-02-01

    We provide an analytical investigation of the pairwise entanglement dynamics for a system, consisting of an arbitrary number of qubits dissipating into a common and non-Markovian environment for both weak- and strong-coupling regimes. In the latter case, a revival of pairwise entanglement due to the memory depth of the environment is observed. The leakage of photons into a continuum state is assumed to be the source of dissipation. We show that for an initially Werner state, the environment washes out the pairwise entanglement, but a series of nonselective measurements can protect the relevant entanglement. On the other hand, by limiting the number of qubits initially in the superposition of single excitation, a stationary entanglement can be created between qubits initially in the excited and ground states. Finally, we determine the stationary distribution of the entanglement versus the total number of qubits in the system.

  7. Extending the applicability of Redfield theories into highly non-Markovian regimes

    CERN Document Server

    Montoya-Castillo, Andrés; Reichman, David R

    2015-01-01

    We present a new, computationally inexpensive method for the calculation of reduced density matrix dynamics for systems with a potentially large number of subsystem degrees of freedom coupled to a generic bath. The approach consists of propagation of weak-coupling Redfield-like equations for the high frequency bath degrees of freedom only, while the low frequency bath modes are dynamically arrested but statistically sampled. We examine the improvements afforded by this approximation by comparing with exact results for the spin-boson model over a wide range of parameter space. The results from the method are found to dramatically improve Redfield dynamics in highly non--Markovian regimes, at a similar computational cost. Relaxation of the mode-freezing approximation via classical (Ehrenfest) evolution of the low frequency modes results in a dynamical hybrid method. We find that this Redfield-based dynamical hybrid approach, which is computationally more expensive than bare Redfield dynamics, yields only a marg...

  8. Multiple-time correlation functions for non-Markovian interaction: Beyond the Quantum Regression Theorem

    CERN Document Server

    Alonso, D; Alonso, Daniel; Vega, In\\'es de

    2004-01-01

    Multiple time correlation functions are found in the dynamical description of different phenomena. They encode and describe the fluctuations of the dynamical variables of a system. In this paper we formulate a theory of non-Markovian multiple-time correlation functions (MTCF) for a wide class of systems. We derive the dynamical equation of the {\\it reduced propagator}, an object that evolve state vectors of the system conditioned to the dynamics of its environment, which is not necessarily at the vacuum state at the initial time. Such reduced propagator is the essential piece to obtain multiple-time correlation functions. An average over the different environmental histories of the reduced propagator permits us to obtain the evolution equations of the multiple-time correlation functions. We also study the evolution of MTCF within the weak coupling limit and it is shown that the multiple-time correlation function of some observables satisfy the Quantum Regression Theorem (QRT), whereas other correlations do no...

  9. Dark matter halo assembly bias: environmental dependence in the non-Markovian excursion set theory

    CERN Document Server

    Zhang, Jun; Riotto, Antonio

    2013-01-01

    In the standard excursion set model for the growth of structure, the statistical properties of haloes are governed by the halo mass and are independent of the larger scale environment in which the haloes reside. Numerical simulations, however, have found the spatial distributions of haloes to depend not only on their mass but also on the details of their assembly history and environment. Here we present a theoretical framework for incorporating this "assembly bias" into the excursion set model. Our derivations are based on modifications of the path integral approach of Maggiore & Riotto (2010) that models halo formation as a non-Markovian random walk process. The perturbed density field is assumed to evolve stochastically with the smoothing scale and exhibits correlated walks in the presence of a density barrier. We write down conditional probabilities for multiple barrier crossings, and derive from them analytic expressions for descendant and progenitor halo mass functions and halo merger rates as a func...

  10. Non-Markovian Quantum State Diffusion for temperature-dependent linear spectra of light harvesting aggregates

    Science.gov (United States)

    Ritschel, Gerhard; Suess, Daniel; Möbius, Sebastian; Strunz, Walter T.; Eisfeld, Alexander

    2015-01-01

    Non-Markovian Quantum State Diffusion (NMQSD) has turned out to be an efficient method to calculate excitonic properties of aggregates composed of organic chromophores, taking into account the coupling of electronic transitions to vibrational modes of the chromophores. NMQSD is an open quantum system approach that incorporates environmental degrees of freedom (the vibrations in our case) in a stochastic way. We show in this paper that for linear optical spectra (absorption, circular dichroism), no stochastics is needed, even for finite temperatures. Thus, the spectra can be obtained by propagating a single trajectory. To this end, we map a finite temperature environment to the zero temperature case using the so-called thermofield method. The resulting equations can then be solved efficiently by standard integrators.

  11. Evolution of entropy in different types of non-Markovian three-level systems: Single reservoir vs. two independent reservoirs

    Indian Academy of Sciences (India)

    JAGHOURI HAKIMEH; SARBISHAEI MOHSEN; JAVIDAN KUROSH

    2016-05-01

    We solve the Nakajima–Zwanzig (NZ) non-Markovian master equation to study the dynamics of different types of three-level atomic systems interacting with bosonic Lorentzian reservoirs at zero temperature. Von Neumann entropy (S) is used to show the evolution of the degree of entanglement of the subsystems. The results presented are also compared with some recently published reports.

  12. Non-Markovian dynamics for an open two-level system without rotating wave approximation: indivisibility versus backflow of information

    Science.gov (United States)

    Zeng, H. S.; Tang, N.; Zheng, Y. P.; Xu, T. T.

    2012-10-01

    By use of the recently presented two measures, the indivisibility and the backflow of information, we study the non-Markovianity of the dynamics for a two-level system interacting with a zero-temperature structured environment without using rotating wave approximation (RWA). In the limit of weak coupling between the system and its reservoir, and by expanding the time-convolutionless (TCL) generator to the forth order with respect to the coupling strength, the time-local non-Markovian master equation for the reduced state of the system is derived. Under the secular approximation, the exact analytic solution is obtained and the sufficient and necessary conditions for the indivisibility and the backflow of information for the system dynamics are presented. In the more general case, we investigate numerically the properties of the two measures for the case of Lorentzian reservoir. Our results show the importance of the counter-rotating terms to the short-time-scale non-Markovian behavior of the system dynamics, further expose the relation between the two measures and their rationality as non-Markovian measures. Finally, the complete positivity of the dynamics of the considered system is discussed.

  13. Quantum Fisher information of the GHZ state due to classical phase noise lasers under non-Markovian environment

    Science.gov (United States)

    Chen, Yu; Zou, Jian; Yang, Zi-Yi; Li, Longwu; Li, Hai; Shao, Bin

    2016-08-01

    The dynamics of N-qubit GHZ state quantum Fisher information (QFI) under phase noise lasers (PNLs) driving is investigated in terms of non-Markovian master equation. We first investigate the non-Markovian dynamics of the QFI of N-qubit GHZ state and show that when the ratio of the PNL rate and the system-environment coupling strength is very small, the oscillations of the QFIs decay slower which corresponds to the non-Markovian region; yet when it becomes large, the QFIs monotonously decay which corresponds to the Markovian region. When the atom number N increases, QFIs in both regions decay faster. We further find that the QFI flow disappears suddenly followed by a sudden birth depending on the ratio of the PNL rate and the system-environment coupling strength and the atom number N, which unveil a fundamental connection between the non-Markovian behaviors and the parameters of system-environment couplings. We discuss two optimal positive operator-valued measures (POVMs) for two different strategies of our model and find the condition of the optimal measurement. At last, we consider the QFI of two atoms with qubit-qubit interaction under random telegraph noises (RTNs).

  14. A Bohmian approach to the non-Markovian non-linear Schrödinger–Langevin equation

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, Andrés F.; Morales-Durán, Nicolás; Bargueño, Pedro, E-mail: p.bargueno@uniandes.edu.co

    2015-05-15

    In this work, a non-Markovian non-linear Schrödinger–Langevin equation is derived from the system-plus-bath approach. After analyzing in detail previous Markovian cases, Bohmian mechanics is shown to be a powerful tool for obtaining the desired generalized equation.

  15. Ultrafast dynamics of laser-pulse excited semiconductors: non-Markovian quantum kinetic equations with nonequilibrium correlations

    Directory of Open Access Journals (Sweden)

    V.V.Ignatyuk

    2004-01-01

    Full Text Available Non-Markovian kinetic equations in the second Born approximation are derived for a two-zone semiconductor excited by a short laser pulse. Both collision dynamics and running nonequilibrium correlations are taken into consideration. The energy balance and relaxation of the system to equilibrium are discussed. Results of numerical solution of the kinetic equations for carriers and phonons are presented.

  16. Nonequilibrium quantum transport coefficients and transient dynamics of full counting statistics in the strong-coupling and non-Markovian regimes

    Science.gov (United States)

    Cerrillo, Javier; Buser, Maximilian; Brandes, Tobias

    2016-12-01

    Nonequilibrium transport properties of quantum systems have recently become experimentally accessible in a number of platforms in so-called full-counting experiments that measure transient and steady-state nonequilibrium transport dynamics. We show that the effect of the measurement back-action can be exploited to establish general relationships between transport coefficients in the transient regime which take the form of fluctuation-dissipation theorems in the steady state. This result becomes most conspicuous in the transient dynamics of open quantum systems under strong-coupling to non-Markovian environments in nonequilibrium settings. In order to explore this regime, a new simulation method based in a hierarchy of equations of motion has been developed. We instantiate our proposal with the study of energetic conductance between two baths connected via a few level system.

  17. Kinetics of self-induced aggregation of Brownian particles: non-Markovian and non-Gaussian features

    CERN Document Server

    Ghosh, Pulak Kumar; Bag, Bidhan Chandra

    2012-01-01

    In this paper we have studied a model for self-induced aggregation in Brownian particle incorporating the non-Markovian and non-Gaussian character of the associated random noise process. In this model the time evolution of each individual is guided by an over-damped Langevin equation of motion with a non-local drift resulting from the local unbalance distributions of the other individuals. Our simulation result shows that colored nose can induce the cluster formation even at large noise strength. Another observation is that critical noise strength grows very rapidly with increase of noise correlation time for Gaussian noise than non Gaussian one. However, at long time limit the cluster number in aggregation process decreases with time following a power law. The exponent in the power law increases remarkable for switching from Markovian to non Markovian noise process.

  18. The Role of the Total Entropy Production in the Dynamics of Open Quantum Systems in Detection of Non-Markovianity

    Science.gov (United States)

    Salimi, S.; Haseli, S.; Khorashad, A. S.; Adabi, F.

    2016-09-01

    The interaction between system and environment is a fundamental concept in the theory of open quantum systems. As a result of the interaction, an amount of correlation (both classical and quantum) emerges between the system and the environment. In this work, we recall the quantity that will be very useful to describe the emergence of the correlation between the system and the environment, namely, the total entropy production. Appearance of total entropy production is due to the entanglement production between the system and the environment. In this work, we discuss about the role of the total entropy production for detecting the non-Markovianity. By utilizing the relation between the total entropy production and total correlation between subsystems, one can see a temporary decrease of total entropy production is a signature of non-Markovianity. We apply our criterion for the special case, where the composite system has initial correlation with environment.

  19. Firing statistics of inhibitory neuron with delayed feedback. II: Non-Markovian behavior.

    Science.gov (United States)

    Kravchuk, K G; Vidybida, A K

    2013-06-01

    The instantaneous state of a neural network consists of both the degree of excitation of each neuron the network is composed of and positions of impulses in communication lines between the neurons. In neurophysiological experiments, the neuronal firing moments are registered, but not the state of communication lines. But future spiking moments depend essentially on the past positions of impulses in the lines. This suggests, that the sequence of intervals between firing moments (inter-spike intervals, ISIs) in the network could be non-Markovian. In this paper, we address this question for a simplest possible neural "net", namely, a single inhibitory neuron with delayed feedback. The neuron receives excitatory input from the driving Poisson stream and inhibitory impulses from its own output through the feedback line. We obtain analytic expressions for conditional probability density P(tn+1|tn, …, t1, t0), which gives the probability to get an output ISI of duration tn+1 provided the previous (n+1) output ISIs had durations tn, …, t1, t0. It is proven exactly, that P(tn+1|tn, …, t1, t0) does not reduce to P(tn+1|tn, …, t1) for any n≥0. This means that the output ISIs stream cannot be represented as a Markov chain of any finite order.

  20. Extracting work from a single reservoir in the non-Markovian underdamped regime.

    Science.gov (United States)

    Paredes-Altuve, Oscar; Medina, Ernesto; Colmenares, Pedro J

    2016-12-01

    We derive optimal-work finite time protocols for a colloidal particle in a harmonic well in the general non-Markovian underdamped regime in contact with a single reservoir. Optimal-work protocols with and without measurements of position and velocity are shown to be linear in time. In order to treat the underdamped regime one must address forcing the particle at the start and at the end of a protocol, conditions which dominate the short time behavior of the colloidal particle. We find that for protocols without measurement the least work by an external agent decreases linearly for forced start-stop conditions while those only forced at starting conditions are quadratic (slower) at short times, while both decrease asymptotically to zero for quasistatic processes. When measurements are performed, protocols with start-end forcing are still more efficient at short times but can be overtaken by start-only protocols at a threshold time. Measurement protocols derive work from the reservoir but always below that predicted by Sagawa's generalization of the second law. Velocity measurement protocols are more efficient in deriving work than position measurements.

  1. Quantum heat current under non-perturbative and non-Markovian conditions: Applications to heat machines

    Science.gov (United States)

    Kato, Akihito; Tanimura, Yoshitaka

    2016-12-01

    We consider a quantum system strongly coupled to multiple heat baths at different temperatures. Quantum heat transport phenomena in this system are investigated using two definitions of the heat current: one in terms of the system energy and the other in terms of the bath energy. When we consider correlations among system-bath interactions (CASBIs)—which have a purely quantum mechanical origin—the definition in terms of the bath energy becomes different. We found that CASBIs are necessary to maintain the consistency of the heat current with thermodynamic laws in the case of strong system-bath coupling. However, within the context of the quantum master equation approach, both of these definitions are identical. Through a numerical investigation, we demonstrate this point for a non-equilibrium spin-boson model and a three-level heat engine model using the reduced hierarchal equations of motion approach under the strongly coupled and non-Markovian conditions. We observe the cyclic behavior of the heat currents and the work performed by the heat engine, and we find that their phases depend on the system-bath coupling strength. Through consideration of the bath heat current, we show that the efficiency of the heat engine decreases as the strength of the system-bath coupling increases, due to the CASBI contribution. In the case of a large system-bath coupling, the efficiency decreases further if the bath temperature is increased, even if the ratio of the bath temperatures is fixed, due to the discretized nature of energy eigenstates. This is also considered to be a unique feature of quantum heat engines.

  2. Quantum Darwinism and non-Markovian dissipative dynamics from quantum phases of the spin-1/2 X X model

    Science.gov (United States)

    Giorgi, Gian Luca; Galve, Fernando; Zambrini, Roberta

    2015-08-01

    Quantum Darwinism explains the emergence of a classical description of objects in terms of the creation of many redundant registers in an environment containing their classical information. This amplification phenomenon, where only classical information reaches the macroscopic observer and through which different observers can agree on the objective existence of such object, has been revived lately for several types of situations, successfully explaining classicality. We explore quantum Darwinism in the setting of an environment made of two level systems which are initially prepared in the ground state of the XX model, which exhibits different phases; we find that the different phases have different abilities to redundantly acquire classical information about the system, the "ferromagnetic phase" being the only one able to complete quantum Darwinism. At the same time we relate this ability to how non-Markovian the system dynamics is, based on the interpretation that non-Markovian dynamics is associated with backflow of information from environment to system, thus spoiling the information transfer needed for Darwinism. Finally, we explore mixing of bath registers by allowing a small interaction among them, finding that this spoils the stored information as previously found in the literature.

  3. Non-Markovian dynamics of single- and two-qubit systems interacting with Gaussian and non-Gaussian fluctuating transverse environments

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Matteo A. C., E-mail: matteo.rossi@unimi.it [Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, 20133 Milano (Italy); Paris, Matteo G. A., E-mail: matteo.paris@fisica.unimi.it [Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, 20133 Milano (Italy); CNISM, Unità Milano Statale, I-20133 Milano (Italy)

    2016-01-14

    We address the interaction of single- and two-qubit systems with an external transverse fluctuating field and analyze in detail the dynamical decoherence induced by Gaussian noise and random telegraph noise (RTN). Upon exploiting the exact RTN solution of the time-dependent von Neumann equation, we analyze in detail the behavior of quantum correlations and prove the non-Markovianity of the dynamical map in the full parameter range, i.e., for either fast or slow noise. The dynamics induced by Gaussian noise is studied numerically and compared to the RTN solution, showing the existence of (state dependent) regions of the parameter space where the two noises lead to very similar dynamics. We show that the effects of RTN noise and of Gaussian noise are different, i.e., the spectrum alone is not enough to summarize the noise effects, but the dynamics under the effect of one kind of noise may be simulated with high fidelity by the other one.

  4. Non-Markovian Entanglement Sudden Death and Rebirth of a Two-Qubit System in the Presence of System-Bath Coherence

    CERN Document Server

    Wang, Hao-Tian; Zou, Yang; Ge, Rong-Chun; Guo, Guang-Can

    2010-01-01

    We present a detailed study of the entanglement dynamics of a two-qubit system coupled to independent non-Markovian environments, employing hierarchy equations. This recently developed theoretical treatment can conveniently solve non-Markovian problems and take into consideration the correlation between the system and bath in an initial state. We concentrate on calculating the death and rebirth time points of the entanglement to obtain a general view of the concurrence curve and explore the behavior of entanglement dynamics with respect to the coupling strength, the characteristic frequency of the noise bath and the environment temperature.

  5. Dynamical matrix for arbitrary quadratic fermionic bath Hamiltonians and non-Markovian dynamics of one and two qubits in an Ising model environment

    Science.gov (United States)

    Iemini, Fernando; da Silva Souza, Leonardo; Debarba, Tiago; Cesário, André T.; Maciel, Thiago O.; Vianna, Reinaldo O.

    2017-05-01

    We obtain the analytical expression for the Kraus decomposition of the quantum map of an environment modeled by an arbitrary quadratic fermionic Hamiltonian acting on one or two qubits, and derive simple functions to check the non-positivity of the intermediate map. These functions correspond to two different sufficient criteria for non-Markovianity. In the particular case of an environment represented by the Ising Hamiltonian, we discuss the two sources of non-Markovianity in the model, one due to the finite size of the lattice, and another due to the kind of interactions.

  6. Generation of long-living entanglement between two distant three-level atoms in non-Markovian environments.

    Science.gov (United States)

    Li, Chuang; Yang, Sen; Song, Jie; Xia, Yan; Ding, Weiqiang

    2017-05-15

    In this paper, a scheme for the generation of long-living entanglement between two distant Λ-type three-level atoms separately trapped in two dissipative cavities is proposed. In this scheme, two dissipative cavities are coupled to their own non-Markovian environments and two three-level atoms are driven by the classical fields. The entangled state between the two atoms is produced by performing Bell state measurement (BSM) on photons leaving the dissipative cavities. Using the time-dependent Schördinger equation, we obtain the analytical results for the evolution of the entanglement. It is revealed that, by manipulating the detunings of classical field, the long-living stationary entanglement between two atoms can be generated in the presence of dissipation.

  7. Anomalous polymer dynamics is non-Markovian: memory effects and the generalized Langevin equation formulation

    NARCIS (Netherlands)

    Panja, D.

    2010-01-01

    Any first course on polymer physics teaches that the dynamics of a tagged monomer of a polymer is anomalously subdiffusive, i.e., the mean-square displacement of a tagged monomer increases as tα for some α < 1 until the terminal relaxation time τ of the polymer. Beyond time τ the motion of the tagge

  8. Role of the lightmatter coupling strength on nonMarkovian phonon effects in semiconductor cavity QED

    DEFF Research Database (Denmark)

    Nielsen, Per Kær; Nielsen, Torben Roland; Lodahl, Peter;

    2011-01-01

    Semiconductor cavity quantum electrodynamical (CQED) devices are believed to be important components for future quantum information technologies. Being composed of a single quantum dot (QD) embedded in a cavity, semiconductor CQED systems resemble atomic CQED systems. However, recent experiments ...

  9. Non-Markovian Second-Order Quantum Master Equation and Its Markovian Limit: Electronic Energy Transfer in Model Photosynthetic Systems

    CERN Document Server

    Singh, Navinder

    2011-01-01

    A direct numerical algorithm for solving the time-nonlocal non-Markovian master equation in the second Born approximation is introduced and the range of utility of this approximation, and of the Markov approximation, is analyzed for the traditional dimer system that models excitation energy transfer in photosynthesis. Specifically, the coupled integro-differential equations for the reduced density matrix are solved by an efficient auxiliary function method in both the energy and site representations. In addition to giving exact results to this order, the approach allows us to computationally assess the range of the reorganization energy and decay rates of the phonon auto-correlation function for which the Markovian Redfield theory and the second order approximation is valid. For example, the use of Redfield theory for $\\lambda> 10 \\textrm{cm}^{-1}$ in systems like Fenna-Mathews-Olson (FMO) type systems is shown to be in error. In addition, analytic inequalities are obtained for the regime of validity of the M...

  10. Polymer length distributions for catalytic polymerization within mesoporous materials: non-Markovian behavior associated with partial extrusion.

    Science.gov (United States)

    Liu, Da-Jiang; Chen, Hung-Ting; Lin, Victor S-Y; Evans, J W

    2010-04-21

    We analyze a model for polymerization at catalytic sites distributed within parallel linear pores of a mesoporous material. Polymerization occurs primarily by reaction of monomers diffusing into the pores with the ends of polymers near the pore openings. Monomers and polymers undergo single-file diffusion within the pores. Model behavior, including the polymer length distribution, is determined by kinetic Monte Carlo simulation of a suitable atomistic-level lattice model. While the polymers remain within the pore, their length distribution during growth can be described qualitatively by a Markovian rate equation treatment. However, once they become partially extruded, the distribution is shown to exhibit non-Markovian scaling behavior. This feature is attributed to the long-tail in the "return-time distribution" for the protruding end of the partially extruded polymer to return to the pore, such return being necessary for further reaction and growth. The detailed form of the scaled length distribution is elucidated by application of continuous-time random walk theory.

  11. Non-Markovian phonon dephasing of a quantum dot in a photonic-crystal nanocavity

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg; Nielsen, Per Kær; Kreiner-Møller, Asger

    2012-01-01

    ) is introduced, which determines the rate of phonon-assisted spontaneous emission. If, e.g., the QD is blue-detuned from the cavity mode, the QD can emit a photon into the cavity mode by emitting the residual energy as a phonon [3]. Our microscopic model allows us to extract the effective phonon DOS, that turns...

  12. Aftershocks in Modern Perspectives: Complex Earthquake Network, Aging, and Non-Markovianity

    CERN Document Server

    Abe, Sumiyoshi

    2012-01-01

    The phenomenon of aftershocks is studied in view of science of complexity. In particular, three different concepts are examined: (i) the complex-network representation of seismicity, (ii) the event-event correlations, and (iii) the effects of long-range memory. Regarding (i), it is shown the clustering coefficient of the complex earthquake network exhibits a peculiar behavior at and after main shocks. Regarding (ii), it is found that aftershocks experience aging, and the associated scaling holds. And regarding (iii), the scaling relation to be satisfied by a class of singular Markovian processes is violated, implying the existence of the long-range memory in processes of aftershocks.

  13. Non-Markovian properties and multiscale hidden Markovian network buried in single molecule time series

    Science.gov (United States)

    Sultana, Tahmina; Takagi, Hiroaki; Morimatsu, Miki; Teramoto, Hiroshi; Li, Chun-Biu; Sako, Yasushi; Komatsuzaki, Tamiki

    2013-12-01

    We present a novel scheme to extract a multiscale state space network (SSN) from single-molecule time series. The multiscale SSN is a type of hidden Markov model that takes into account both multiple states buried in the measurement and memory effects in the process of the observable whenever they exist. Most biological systems function in a nonstationary manner across multiple timescales. Combined with a recently established nonlinear time series analysis based on information theory, a simple scheme is proposed to deal with the properties of multiscale and nonstationarity for a discrete time series. We derived an explicit analytical expression of the autocorrelation function in terms of the SSN. To demonstrate the potential of our scheme, we investigated single-molecule time series of dissociation and association kinetics between epidermal growth factor receptor (EGFR) on the plasma membrane and its adaptor protein Ash/Grb2 (Grb2) in an in vitro reconstituted system. We found that our formula successfully reproduces their autocorrelation function for a wide range of timescales (up to 3 s), and the underlying SSNs change their topographical structure as a function of the timescale; while the corresponding SSN is simple at the short timescale (0.033-0.1 s), the SSN at the longer timescales (0.1 s to ˜3 s) becomes rather complex in order to capture multiscale nonstationary kinetics emerging at longer timescales. It is also found that visiting the unbound form of the EGFR-Grb2 system approximately resets all information of history or memory of the process.

  14. Manifestation of macroscopic correlations in elementary reaction kinetics. I. Irreversible reaction A +A→product

    Science.gov (United States)

    Doktorov, Alexander B.; Kipriyanov, Alexander A.; Kipriyanov, Alexey A.

    2010-05-01

    Using an modern many-particle method for the derivation of non-Markovian binary kinetic equations, we have treated theoretically the applicability of the encounter theory (ET) (the prototype of the collision theory) concepts to the widely known diffusion assisted irreversible bulk reaction A +A→product (for example, radical reaction) in dilute solutions. The method shows that the agreement with the ET is observed when the familiar integral ET is employed which in this method is just a step in the derivation of kinetic equations. It allows for two-particle correlations only, but fails to take account of correlation of reactant simultaneously with the partner of the encounter and the reactant in the bulk. However, the next step leading to the modified ET under transformation of equations to the regular form both extends the time range of the applicability of ET rate equation (as it was for reactions proceeding with one of the reactants in excess), and gives the equation of the generalized ET. In full agreement with physical considerations, this theory reveals macroscopic correlations induced by the encounters in the reservoir of free walks. This means that the encounters of reactants in solution are correlated on a rather large time interval of the reaction. Though any nonstationary (non-Markovian) effects manifest themselves rather weakly in the kinetics of the bimolecular reaction in question, just the existence of the revealed macroscopic correlations in the binary theory is of primary importance. In particular, it means that the well-known phenomena which are generally considered to be associated solely with correlation of particles on the encounter (for example, chemically induced dynamic nuclear polarization) may be induced by correlation in the reservoir of free random walks of radicals in solution.

  15. Manifestation of macroscopic correlations in elementary reaction kinetics. I. Irreversible reaction A+A-->product.

    Science.gov (United States)

    Doktorov, Alexander B; Kipriyanov, Alexander A; Kipriyanov, Alexey A

    2010-05-28

    Using an modern many-particle method for the derivation of non-Markovian binary kinetic equations, we have treated theoretically the applicability of the encounter theory (ET) (the prototype of the collision theory) concepts to the widely known diffusion assisted irreversible bulk reaction A+A-->product (for example, radical reaction) in dilute solutions. The method shows that the agreement with the ET is observed when the familiar integral ET is employed which in this method is just a step in the derivation of kinetic equations. It allows for two-particle correlations only, but fails to take account of correlation of reactant simultaneously with the partner of the encounter and the reactant in the bulk. However, the next step leading to the modified ET under transformation of equations to the regular form both extends the time range of the applicability of ET rate equation (as it was for reactions proceeding with one of the reactants in excess), and gives the equation of the generalized ET. In full agreement with physical considerations, this theory reveals macroscopic correlations induced by the encounters in the reservoir of free walks. This means that the encounters of reactants in solution are correlated on a rather large time interval of the reaction. Though any nonstationary (non-Markovian) effects manifest themselves rather weakly in the kinetics of the bimolecular reaction in question, just the existence of the revealed macroscopic correlations in the binary theory is of primary importance. In particular, it means that the well-known phenomena which are generally considered to be associated solely with correlation of particles on the encounter (for example, chemically induced dynamic nuclear polarization) may be induced by correlation in the reservoir of free random walks of radicals in solution.

  16. Counting statistics of transport through Coulomb blockade nanostructures: High-order cumulants and non-Markovian effects

    DEFF Research Database (Denmark)

    Flindt, Christian; Novotny, Tomás; Braggio, Alessandro

    2010-01-01

    Recent experimental progress has made it possible to detect in real-time single electrons tunneling through Coulomb blockade nanostructures, thereby allowing for precise measurements of the statistical distribution of the number of transferred charges, the so-called full counting statistics...

  17. [Dermatologic manifestation of undesirable effects of drugs (excluding cytostatic drugs)].

    Science.gov (United States)

    Villette, B; Rybojad, M; Puissant, A

    1989-01-01

    Medications, consumed more and more frequently as a result of self-medication or prescribed under medical supervision, have multiple side effects, including dermatological ones. In fact, the latter represent the primary cause of drug intolerance. However, the diagnosis is not always made easily and is based upon standardized norms defined by pharmacology control centers. Fixed pigmented eruptions are the only erythema solely of drug-induced origin. Failure to recognize a drug-induced dermatological manifestation can be fatal if the drug is taken again, as in the case of toxic epidermal necrolysis.

  18. The Casimir effect physical manifestations of zero-point energy

    CERN Document Server

    Milton, K A

    2001-01-01

    In its simplest manifestation, the Casimir effect is a quantum force of attraction between two parallel uncharged conducting plates. More generally, it refers to the interaction - which may be either attractive or repulsive - between material bodies due to quantum fluctuations in whatever fields are relevant. It is a local version of the van der Waals force between molecules. Its sweep ranges from perhaps its being the origin of the cosmological constant to its being responsible for the confinement of quarks. This monograph develops the theory of such forces, based primarily on physically tran

  19. Analyzing 2D THz-Raman spectroscopy using a non-Markovian Brownian oscillator model with nonlinear system-bath interactions

    CERN Document Server

    Ikeda, Tatsushi; Tanimura, Yoshitaka

    2015-01-01

    We explore and describe the roles of inter-molecular vibrations in terms of a Brownian oscillator (BO) model with linear-linear (LL) and square-linear (SL) system-bath interactions, which we use to analyze two-dimensional (2D) THz-Raman spectra obtained by means of molecular dynamics (MD) simulations. In addition to linear absorption (1D IR), we calculate 2D Raman-THz-THz, THz-Raman-THz, and THz-THz-Raman signals for liquid formamide, water, and methanol using an equilibrium non-equilibrium hybrid MD simulation. The calculated 1D IR and 2D THz-Raman signals are then accounted by the LL+SL BO model with the use of the hierarchal Fokker-Planck equations for a non-perturbative and non-Markovian noise. All of the characteristic 2D profiles of the simulated signals are reproduced using the LL+SL BO model, indicating that the present model captures the essential features of the inter-molecular motion. We analyze the fitted the 2D profiles in terms of anharmonicity, nonlinear polarizability, and dephasing time. The ...

  20. Effect of maternal transmissions on clinical manifestations of myotonic dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, I.; Koike, R.; Onodera, O. [Niigata Univ. (Japan)] [and others

    1994-09-01

    The mutation of myotonic dystrophy (DM) has been identified as unstable expansions of trinucleotide CTG repeat, located on chromosome 19q13-3. Although previous investigations have emphasized the strong association of the sizes of the CTG repeat with ages of onset as well as the clinical manifestations, effects of the paternal or maternal transmissions other than CTG repeats on the clinical manifestations in DM have not been evaluated in detail. To investigate how parental transmission affect the DM phenotype, we analyzed 15 cases of paternal transmission and 25 cases of maternal transmission. We have classified DM patients into 4 clinical grades. As in accordance with previous reports, there is a good correlation on sizes of the CTG repeat with their clinical features. The sizes of the CTG repeat in congenital DM patients (4.13{plus_minus}0.221 kbp) (Mean {plus_minus}SEM), who inherited mutant genes from their mothers, were not significantly larger than those of non-congenital DM patients (3.65 {plus_minus}0.36 kbp). As it has been well established that congenital DM patients are born to affected mothers, we investigated to see if there are any parental bias on the clinical manifestations in non-congenital DM. We classified each case into 4 classes depending on the size ranges of the CTG repeat (0 to 1.5 kbp, 1.5 to 3.0 kbp, 3.0 to 4.5 kbp, 4.5 kbp<). In each group of the size ranges of the CTG repeat, the distribution of cases among grades I to III were compared between paternally and maternally transmitted cases. There were statistically significant differences in the distributions of cases among grades I to III for the size ranges of 3 to 4.5 kbp expansions (p<0.01) and over 4.5 kbp expansions (p<0.05) on {chi}{sup 2} test, respectively. The results revealed that maternally transmitted cases tend to show severe phenotypes compared to paternally transmitted ones even if they have similar sizes of CTG repeat.

  1. Effects of manifest ethnic identification on employment discrimination.

    Science.gov (United States)

    Barron, Laura G; Hebl, Michelle; King, Eden B

    2011-01-01

    Evidence from recent laboratory experiments suggests that ethnic identification can lead to negative evaluations of ethnic minorities (Kaiser & Pratt-Hyatt, 2009). The current research considers the generalizability of these findings to face-to-face interactions in contexts wherein impression management concerns are salient: the workplace hiring process. In a field experiment, Black, Hispanic, and Irish individuals applied for retail jobs with or without visible display of their ethnic identification. Analysis of indicators of formal (e.g., application offering, interview scheduling) and interpersonal discrimination (e.g., interaction length, nonverbal negativity) suggest store personnel interacting with other-race applicants exhibited greater positivity and longer interactions when applicants displayed ethnic identification than when they did not. The findings suggest that psychologists need to understand not only attitudes or intentions expressed in the lab, but also the behavioral consequences of manifest group identity as they unfold in natural environments.

  2. Manifestly scale-invariant regularization and quantum effective operators

    CERN Document Server

    Ghilencea, D.M.

    2016-01-01

    Scale invariant theories are often used to address the hierarchy problem, however the regularization of their quantum corrections introduces a dimensionful coupling (dimensional regularization) or scale (Pauli-Villars, etc) which break this symmetry explicitly. We show how to avoid this problem and study the implications of a manifestly scale invariant regularization in (classical) scale invariant theories. We use a dilaton-dependent subtraction function $\\mu(\\sigma)$ which after spontaneous breaking of scale symmetry generates the usual DR subtraction scale $\\mu(\\langle\\sigma\\rangle)$. One consequence is that "evanescent" interactions generated by scale invariance of the action in $d=4-2\\epsilon$ (but vanishing in $d=4$), give rise to new, finite quantum corrections. We find a (finite) correction $\\Delta U(\\phi,\\sigma)$ to the one-loop scalar potential for $\\phi$ and $\\sigma$, beyond the Coleman-Weinberg term. $\\Delta U$ is due to an evanescent correction ($\\propto\\epsilon$) to the field-dependent masses (of...

  3. Memory-effect-induced macroscopic-microscopic entanglement

    Science.gov (United States)

    Mu, Qingxia; Zhao, Xinyu; Yu, Ting

    2016-07-01

    We study optomechanical entanglement between an optical cavity field and a movable mirror coupled to a non-Markovian environment. The non-Markovian quantum-state diffusion approach and the non-Markovian master equation are shown to be useful in investigating entanglement generation between the cavity field and the movable mirror. The simple model presented in this paper demonstrates several interesting properties of optomechanical entanglement that are associated with environment memory effects. It is evident that the effective environment central frequency can be used to modulate the optomechanical entanglement. In addition, we show that the maximum entanglement may be achieved by properly choosing the effective detuning, which is significantly dependent on the strength of the memory effect of the environment.

  4. Dynamics of Quantum Entanglement in Reservoir with Memory Effects

    Institute of Scientific and Technical Information of China (English)

    郝翔; 沙金巧; 孙坚; 朱士群

    2012-01-01

    The non-Markovian dynamics of quantum entanglement is studied by the Shabani-Lidar master equation when one of entangled quantum systems is coupled to a local reservoir with memory effects. The completely positive reduced dynamical map can be constructed in the Kraus representation. Quantum entanglement decays more slowly in the non-Markovian environment. The decoherence time for quantum entanglement can be markedly increased with the change of the memory kernel. It is found out that the entanglement sudden death between quantum systems and entanglement sudden birth between the system and reservoir occur at different instants.

  5. The Hall-Petch effect as a manifestation of the general size effect

    Science.gov (United States)

    Li, Y.; Bushby, A. J.; Dunstan, D. J.

    2016-06-01

    The experimental evidence for the Hall-Petch dependence of strength on the inverse square-root of grain size is reviewed critically. Both the classic data and more recent results are considered. While the data are traditionally fitted to the inverse square-root dependence, they also fit well to many other functions, both power law and non-power law. There have been difficulties, recognized for half-a-century, in the inverse square-root expression. It is now explained as an artefact of faulty data analysis. A Bayesian meta-analysis shows that the data strongly support the simple inverse or lnd/d expressions. Since these expressions derive from underlying theory, they are also more readily explicable. It is concluded that the Hall-Petch effect is not to be explained by the variety of theories found in the literature, but is a manifestation of, or to be underlain by the general size effect observed throughout micromechanics, owing to the inverse relationship between the stress required and the space available for dislocation sources to operate.

  6. Behavioral and electroencephalographic manifestations of thioacetamide-induced encephalopathy: Possible mechanisms of neurotoxic effects

    Directory of Open Access Journals (Sweden)

    Mladenović D.

    2012-01-01

    Full Text Available Although there is still no ideal experimental model of hepatic encephalopathy, thioacetamide is widely used for the induction of acute and chronic liver failure. Thioacetamide exerts hepatotoxic effects through the formation of toxic metabolites in hepatocytes, oxidative stress and calcium mobilization. An ideal experimental model of hepatic encephalopathy should have similar behavioral and electroencephalographic manifestations as human encephalopathy. Thioacetamide induces motor manifestations in a dose-dependent manner. Milder forms of thioacetamide-induced encephalopathy are associated with an increase in relative alpha power, while more severe forms are followed by a flattening of the electroencephalogram. liver failure-induced hyperammonemia has a pivotal role in the neurotoxic effects of thioacetamide. Hyperammonemia induces brain edema, alterations in neurotransmission, oxidative stress, mitochondrial dysfunction and neuronal death. The aim of this article is to review the behavioral and electroencephalographic manifestations of thioacetamide-induced encephalopathy, as well as to summarize potential mechanisms involved in thioacetamide neurotoxicity.[Acknowledgments. This work was supported by the Ministry of Education and Science of Serbia, Grant No 175032

  7. Signaling pathways underpinning the manifestations of ionizing radiation-induced bystander effects.

    Science.gov (United States)

    Hamada, Nobuyuki; Maeda, Munetoshi; Otsuka, Kensuke; Tomita, Masanori

    2011-06-01

    For nearly a century, ionizing radiation has been indispensable to medical diagnosis. Furthermore, various types of electromagnetic and particulate radiation have also been used in cancer therapy. However, the biological mechanism of radiation action remains incompletely understood. In this regard, a rapidly growing body of experimental evidence indicates that radiation exposure induces biological effects in cells whose nucleus has not been irradiated. This phenomenon termed the 'non-targeted effects' challenges the long-held tenet that radiation traversal through the cell nucleus is a prerequisite to elicit genetic damage and biological responses. The non-targeted effects include biological effects in cytoplasm-irradiated cells, bystander effects that arise in non-irradiated cells having received signals from irradiated cells, and genomic instability occurring in the progeny of irradiated cells. Such non-targeted responses are interrelated, and the bystander effect is further related with an adaptive response that manifests itself as the attenuated stressful biological effects of acute high-dose irradiation in cells that have been pre-exposed to low-dose or low-dose-rate radiation. This paper reviews the current body of knowledge about the bystander effect with emphasis on experimental approaches, in vitro and in vivo manifestations, radiation quality dependence, temporal and spatial dependence, proposed mechanisms, and clinical implications. Relations of bystander responses with the effects in cytoplasm-irradiated cells, genomic instability and adaptive response will also be briefly discussed.

  8. 基于单边傅里叶变换的非马尔科夫自发辐射研究%Non-Markovian Spontaneous Emission Research Based on One-sided Fourier Transformation

    Institute of Scientific and Technical Information of China (English)

    刘景锋; 李凌燕

    2013-01-01

    Based on one-sided Fourier transformation, a general method is presented to research the spontaneous decay dynamics of an emitter in homogeneous media, non-leaky cavity, leaky cavity and photonic band gap material. It is found that the spontaneous decay properties of the emitters are strongly dependent on the local density of states. The spontaneous emission properties of the emitters can be manipulated through engineering the local density of stats and the high-performance optoelectronic device and quantum information processing device are obtained. This method can be used in Markovian or non-Markovian bath-reservoir environments.%基于单边傅里叶变换,本文提出一种研究辐射子的自发衰减动力学演化的普适方法.利用该方法研究了辐射子处于均匀介质、理想微腔和泄露微腔中的自发辐射动力学演化问题,最后并把这种方法用于处理光子带隙材料中的辐射动力学演化问题.结果表明:辐射子的自发辐射动力学特性由局域态密度决定,可以通过调控辐射子周围的局域态密度来调控辐射子的自发辐射特性,为实现新型的光电子器件提供了理论基础.该方法不仅适用于马尔科夫热库的情况也适用于非马尔科夫热库的情况.

  9. Nonlinear effects manifested in infrasonic signals in the region of a geometric shadow

    Science.gov (United States)

    Kulichkov, S. N.; Golikova, E. V.

    2013-01-01

    Nonlinear effects manifested in infrasonic signals passing through different atmospheric heights and recorded in the region of a geometric shadow have been studied. The source of infrasound was a surface explosion equivalent to 20-70 t of TNT. The frequencies of the spectral maxima of infrasonic signals, which correspond to the reflections of acoustic pulses from atmospheric inhomogeneities at different heights within the stratosphere-mesosphere-lower thermosphere layer, were calculated using the nonlinear-theory method. A satisfactory agreement between experimental and calculated data was obtained.

  10. Manifestations of phase-coherent transport in graphene: The Josephson effect, weak localization, and aperiodic conductance fluctuations

    NARCIS (Netherlands)

    Heersche, H.B.; Jarillo-Herrero, P.; Oostinga, J.B.; Vandersypen, L.M.K.; Morpurgoa, A.F.

    2007-01-01

    The electronic transport properties of graphene exhibit pronounced differences from those of conventional two dimensional electron systems investigated in the past. As a consequence, well established phenomena such as the integer quantum Hall effect and weak localization manifest themselves differen

  11. The effect of neonatal gene therapy on skeletal manifestations in mucopolysaccharidosis VII dogs after a decade.

    Science.gov (United States)

    Xing, Elizabeth M; Knox, Van W; O'Donnell, Patricia A; Sikura, Tracey; Liu, Yuli; Wu, Susan; Casal, Margret L; Haskins, Mark E; Ponder, Katherine P

    2013-06-01

    Mucopolysaccharidosis (MPS) VII is a lysosomal storage disease due to deficient activity of β-glucuronidase (GUSB), and results in glycosaminoglycan accumulation. Skeletal manifestations include bone dysplasia, degenerative joint disease, and growth retardation. One gene therapy approach for MPS VII involves neonatal intravenous injection of a gamma retroviral vector expressing GUSB, which results in stable expression in liver and secretion of enzyme into blood at levels predicted to be similar or higher to enzyme replacement therapy. The goal of this study was to evaluate the long-term effect of neonatal gene therapy on skeletal manifestations in MPS VII dogs. Treated MPS VII dogs could walk throughout their lives, while untreated MPS VII dogs could not stand beyond 6 months and were dead by 2 years. Luxation of the coxofemoral joint and the patella, dysplasia of the acetabulum and supracondylar ridge, deep erosions of the distal femur, and synovial hyperplasia were reduced, and the quality of articular bone was improved in treated dogs at 6 to 11 years of age compared with untreated MPS VII dogs at 2 years or less. However, treated dogs continued to have osteophyte formation, cartilage abnormalities, and an abnormal gait. Enzyme activity was found near synovial blood vessels, and there was 2% as much GUSB activity in synovial fluid as in serum. We conclude that neonatal gene therapy reduces skeletal abnormalities in MPS VII dogs, but clinically-relevant abnormalities remain. Enzyme replacement therapy will probably have similar limitations long-term.

  12. Manifestation of unusual size effects in granular thin films prepared by pulsed laser deposition

    Science.gov (United States)

    Sergeenkov, S.; Cichetto, L.; Diaz, J. C. C. A.; Bastos, W. B.; Longo, E.; Araújo-Moreira, F. M.

    2016-11-01

    We demonstrate manifestation of some rather unusual size effects in granular thin films prepared by a pulsed laser deposition technique. We observed that the temperature dependence of resistivity ρ(T) notably depends on the relation between the grain size Rg and the film thickness d. Namely, more granular LaNiO3 thin films (with small values of Rg) grown on LaAlO3 substrate are found to follow a universal ρ(T) ∝T 3 / 2 law for all the measured temperatures. While less granular thin films (with larger values of Rg), exhibit a more complicated behavior accompanied by a clear-cut crossover (around Tcr = 200 K), from ρ(T) ∝T 3 / 2 (for 20 K temperature size effects (when an average grain size Rg becomes comparable with the thermal de Broglie wavelength Λ) leading to the crossover temperature Tcr ∝(d /Rg) 2 .

  13. Extrahepatic manifestations of HCV.

    Science.gov (United States)

    Grignoli, R; Goossens, N; Negro, F

    2015-03-01

    The hepatic consequences of an infection with the hepatitis C virus (HCV) are well recognised, but extrahepatic manifestations of HCV may be just as severe. Here we have reviewed various extrahepatic manifestations of HCV such as mixed cryoglobulinemia, lymphoma, metabolic features and neurologic consequences and we discuss pathogenesis and management of these clinical problems. We concluded with important aspects of therapy with novel anti-HCV agents and its effects on extrahepatic manifestations.

  14. Manifestation of transient effects in fission induced by relativistic heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Jurado, B.; Schmitt, C.; Schmidt, K.H.; Benlliure, J. [Universidad de Santiago de Compostela (Spain); Junghans, A.R. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany)

    2004-03-01

    We examine the manifestation of transient effects in fission by analysing experimental data where fission is induced by peripheral heavy-ion collisions at relativistic energies. Available total nuclear fission cross sections of {sup 238}U at1.A GeV on gold and uranium targets are compared with a nuclear-reaction code, where transient effects in fission are modelled using different approximations to the numerical time-dependent fission-decay width: a new analytical description based on the solution of the Fokker-Planck equation and two widely used but less realistic descriptions, a step function and an exponential-like function. The experimental data are only reproduced when transient effects are considered. The deduced value of the dissipation strength {beta} depends strongly on the approximation applied for the time-dependent fission-decay width and is estimated to be of the order of 2 x 10{sup 21} s{sup -1}. A careful analysis sheds severe doubts on the use of the exponential-like in-growth function largely used in the past. Finally, we discuss which should be the characteristics of experimental observables to be most sensitive to transient effects in fission. (orig.)

  15. Herpes zoster vaccine effectiveness and manifestations of herpes zoster and associated pain by vaccination status.

    Science.gov (United States)

    Marin, Mona; Yawn, Barbara P; Hales, Craig M; Wollan, Peter C; Bialek, Stephanie R; Zhang, John; Kurland, Marge J; Harpaz, Rafael

    2015-01-01

    Options for managing herpes zoster (HZ)-related pain and complications have limited effectiveness, making HZ prevention through vaccination an important strategy. Limited data are available on HZ vaccine effectiveness against confirmed HZ and manifestations of HZ among vaccinated persons. We conducted a matched case-control study to assess HZ vaccine effectiveness for prevention of HZ and other HZ-related outcomes and a cohort study of persons with HZ to compare HZ-related outcomes by vaccination status. Cases were identified through active surveillance among persons age ≥ 60 years with HZ onset and health-care encounters during 2010-2011 in Southeastern Minnesota. Controls were age- and sex-matched to cases. Data were collected by medical record review and from participants via interviews and daily pain diaries. 266 HZ case-patients and 362 matched controls were enrolled in the vaccine effectiveness studies and 303 case-patients in the cohort study of HZ characteristics by vaccination status. Vaccination was associated with 54% (95% CI:32%-69%) reduction in HZ incidence, 58% (95% CI:31%-75%) reduction in HZ prodromal symptoms, and 70% (95% CI:33%-87%) reduction in medically-attended prodrome. HZ vaccine was statistically significant effective at preventing postherpetic neuralgia (PHN) measured at 30 d after rash onset, 61% (95% CI: 22%-80%). Among persons who developed HZ, no differences were found by vaccination status in severity or duration of HZ pain after rash onset. In this population-based study, HZ vaccination was associated with >50% reduction in HZ, HZ prodrome, and medically-attended prodrome.

  16. Myelofibrosis-associated complications: pathogenesis, clinical manifestations, and effects on outcomes

    Directory of Open Access Journals (Sweden)

    Mughal TI

    2014-01-01

    Full Text Available Tariq I Mughal,1 Kris Vaddi,2 Nicholas J Sarlis,2 Srdan Verstovsek31Tufts University School of Medicine, Boston, MA, 2Incyte Corporation, Wilmington, DE, 3Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX, USAAbstract: Myelofibrosis (MF is a rare chronic BCR-ABL1 (breakpoint cluster region-Abelson murine leukemia viral oncogene homologue 1-negative myeloproliferative neoplasm characterized by progressive bone marrow fibrosis, inefficient hematopoiesis, and shortened survival. The clinical manifestations of MF include splenomegaly, consequent to extramedullary hematopoiesis, cytopenias, and an array of potentially debilitating abdominal and constitutional symptoms. Dysregulated Janus kinase (JAK-signal transducer and activator of transcription signaling underlies secondary disease-associated effects in MF, such as myeloproliferation, bone marrow fibrosis, constitutional symptoms, and cachexia. Common fatal complications of MF include transformation to acute leukemia, thrombohemorrhagic events, organ failure, and infections. Potential complications from hepatosplenomegaly include portal hypertension and variceal bleeding, whereas extramedullary hematopoiesis outside the spleen and liver – depending on the affected organ – may result in intracranial hypertension, spinal cord compression, pulmonary hypertension, pleural effusions, lymphadenopathy, skin lesions, and/or exacerbation of abdominal symptoms. Although allogeneic stem cell transplantation is the only potentially curative therapy, it is suitable for few patients. The JAK1/JAK2 inhibitor ruxolitinib is effective in improving splenomegaly, MF-related symptoms, and quality-of-life measures. Emerging evidence that ruxolitinib may be associated with a survival benefit in intermediate- or high-risk MF suggests the possibility of a disease-modifying effect. Consequently, ruxolitinib could provide a treatment backbone to which other (conventional and novel

  17. Delayed manifestations of CNS effects in formerly exposed printers--a 20-year follow-up.

    Science.gov (United States)

    Nordling Nilson, Linda; Karlson, Björn; Nise, Gun; Malmberg, Birgitta; Orbæk, Palle

    2010-01-01

    Whether long-term occupational exposure to organic solvents may affect mental and cognitive functioning later in life, remains unclear. In this study, twelve rotogravure printers formerly exposed to toluene and 19 referents, all initially examined in the mid-1980s, were reexamined after twenty years, applying neuropsychological tests, symptoms and social interaction questionnaires, medical examination, and exposure assessment of each individual's cumulative exposure. By far the most extensive exposure, mainly toluene, had occurred before 1985. The printers were found to have deteriorated more than their referents in cognitive functioning affecting reasoning and associative learning. No relevant additional exposure during the lengthy time period between assessments could explain this discrepancy. In addition, printers performed significantly worse than the referents in verbal memory and sustained attention at follow-up, where also a dose-effect relationship was noted for reasoning. While the printers did not report more subjective cognitive complaints than the referents, a slightly higher depression score was noted for the printers. The findings of significantly worse deteriorations in cognitive functioning in previously toluene-exposed printers are in line with our hypothesis that sub-clinical deficits during the working life may become manifest later in life, indicating that exposure may in fact interact with ageing. However, considering the small study groups the results must be interpreted with caution. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Effects of ovarian hormones on manifestation of purulent endometritis in rat uteruses infected with Escherichia coli.

    Science.gov (United States)

    Nishikawa, Y; Baba, T

    1985-01-01

    To assess the influence of hormones on uterine infections, Escherichia coli was infused into uterine lumens of ovariectomized or adrenoovariectomized rats receiving exogenous administration of various doses of ovarian hormones. Large numbers of E. coli were recovered from the rat uterine lumens, irrespective of hormonal influences. The number of leukocytes in the uterine flushings, representing the magnitude of purulent inflammation, differed significantly depending upon the hormonal regimen given to each host. Purulent endometritis was induced by E. coli in ovariectomized rats receiving progesterone or corn oil (hormone vehicle). Infections were asymptomatic in rats receiving estradiol, but promethazine-treated uterine horns were susceptible to infection. When progesterone was administered along with estradiol, purulent inflammation was caused by E. coli, but the number of leukocytes in the uterine lumens was significantly less than that obtained from the rats treated with progesterone or corn oil. These effects of ovarian hormones on uterine infections were observed in adrenoovariectomized rats as well as in ovariectomized rats. It is suggested that estradiol alters the nature of endometrial epithelium and prevent manifestation of purulent endometritis; progesterone antagonizes estradiol. Adrenal hormones appear not to participate in the pathogenesis of endometritis induced by E. coli.

  19. Dynamics of speckles with a small number of scattering events: specific features of manifestation of the Doppler effect.

    Science.gov (United States)

    Ulyanov, Sergey S

    2014-04-01

    Spectra of intensity fluctuations of dynamic non-Gaussian speckles formed with a small number of scattering events have been studied theoretically and experimentally. A new type of manifestation of the Doppler effect has been observed. The dependence of frequency position of the Doppler peak and the shape of the Doppler spectrum on the number of scatterers has been analyzed.

  20. Acute effects of riociguat in borderline or manifest pulmonary hypertension associated with chronic obstructive pulmonary disease.

    Science.gov (United States)

    Ghofrani, Hossein A; Staehler, Gerd; Grünig, Ekkehard; Halank, Michael; Mitrovic, Veselin; Unger, Sigrun; Mueck, Wolfgang; Frey, Reiner; Grimminger, Friedrich; Schermuly, Ralph T; Behr, Juergen

    2015-06-01

    Riociguat is the first oral soluble guanylate cyclase stimulator shown to improve pulmonary hemodynamics in patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (PH). This pilot study assessed the impact of a single dose of riociguat on hemodynamics, gas exchange, and lung function in patients with PH associated with chronic obstructive pulmonary disease (COPD). Adults with COPD-associated borderline or manifest PH (pulmonary vascular resistance > 270 dyn·s·cm(-5), mean pulmonary artery pressure ≥ 23 mmHg, ratio of forced expiratory volume in 1 second [FEV1] to forced vital capacity 70%, and partial pressure of oxygen and carbon dioxide in arterial blood > 50 and ≤ 55 mmHg, respectively) received riociguat 1 or 2.5 mg during right heart catheterization. Twenty-two patients completed the study (11 men, 11 women, aged 56-82 years; 1-mg group: n = 10 [mean FEV1: 43.1%]; 2.5-mg group: n = 12 [mean FEV1: 41.2%]). Riociguat caused significant improvements (P mmHg [-11.44%]; 2.5 mg: -4.83 mmHg [-14.76%]) and pulmonary vascular resistance (1 mg: -58.32 dyn·s·cm(-5) [-15.35%]; 2.5 mg: -123.8 dyn·s·cm(-5) [-32.96%]). No relevant changes in lung function or gas exchange were observed. Single doses of riociguat were well tolerated and showed promising hemodynamic effects without untoward effects on gas exchange or lung function in patients with COPD-associated PH. Placebo-controlled studies of chronic treatment with riociguat are warranted.

  1. Dynamic Solvent Effect on Ultrafast Charge Recombination Kinetics in Excited Donor-Acceptor Complexes.

    Science.gov (United States)

    Mikhailova, Tatyana V; Mikhailova, Valentina A; Ivanov, Anatoly I

    2016-11-23

    Manifestation of the dynamic solvent effect (DSE) on the charge recombination (CR) kinetics of photoexcited donor-acceptor complexes in polar solvents has been investigated within the framework of the multichannel stochastic model. The model takes into account the reorganization of both the solvent and a number of intramolecular high-frequency vibration modes as well as their relaxation. The non-Markovian solvent dynamics is described in terms of two relaxation modes. The similarities and differences inherent to ultrafast charge transfer reactions occurring in the nonequilibrium and thermal regimes have been identified. The most important differences are as follows: (1) the DSE is strong in the area of weak exergonicity and is weak in the area of strong exergonicity for thermal reactions, whereas for the nonequilibrium reactions, the regions of strong and weak DSEs are reversed; (2) an increase in the electronic coupling value results in a decrease in the magnitude of DSE for nonequilibrium electron transfer and in its increase for the thermal reactions; and (3) the two-staged regime most clearly manifests if the reorganization energy of the relaxation modes noticeably exceeds the CR free-energy gap. With an increase in electronic coupling, the kinetics approaches the exponential regime because in the limit of strong electronic coupling, the reaction includes only single, nonequilibrium, stage.

  2. Effect of gender, biochemical parameters & parathyroid surgery on gastrointestinal manifestations of symptomatic primary hyperparathyroidism

    Directory of Open Access Journals (Sweden)

    Viral N Shah

    2014-01-01

    Full Text Available Background & objectives: Information on gastrointestinal manifestations and then response after curative parathyroid surgery is scarce in symptomatic primary hyperparathyroidism (PHPT. This study was carried out to analyse gastrointestinal manifestations in patients with PHPT and their associations with biochemical parameters. Methods: This retrospective study included 153 patients with symptomatic primary hyperparathyroidism (PHPT. The signs and symptoms pertaining to gastrointestinal system were analyzed. The difference of symptoms between men and women and difference in biochemical parameters in presence of different symptoms were evaluated. The relationship between serum calcium, phosphate and parathyroid hormone (PTH levels with presence of gallstone and pancreatitis was also studied. Result: Of the 153 patients, 46 (30% were men. The mean age was 39.2 ± 13.9 yr. Nearly 80 per cent of PHPT patients had at least one symptom/ sign related to gastrointestinal system. The most common gastrointestinal manifestations were abdominal pain 66 (43%, constipation 55 (36%, and nausea/or vomiting 46 (30%. Nearly one-fourth 34 (22% of patients had a history of either gallstone disease or cholecystectomy or both. The prevalence of gallstone disease was higher in women (P<0.05. Imaging and biochemical evidence of pancreatitis was found in 27 (18% patients. Pancreatitis was more common in men compared to women (P<0.05 despite the higher prevalence of gallstones in women. Serum calcium, phosphate or PTH levels were not associated with high risk for gallstone disease, however, serum calcium (P<0.05 was associated with 1.3 times higher risk of developing pancreatitis. In majority of patients, gastrointestinal manifestations resolved within three months of curative parathyroidectomy. Except two patients, none had recurrence of pancreatitis. Interpretation & conclusions: The study revealed that the gastrointestinal symptoms were common in patients with

  3. THE EFFECTS OF SPECIFIC TRAINING ON THE FORMS OF SPEED MANIFESTATION IN JUDO

    Directory of Open Access Journals (Sweden)

    Galea Ioan

    2015-10-01

    Full Text Available The purpose of the study was to investigate the influences specific speed training on the forms of its manifestation in judo. Methods: The subjects of the survey were two 10-student groups practicing judo at C.S.S. Gloria of Arad – a control group (C.Gr.: M age = 11.5 ±1.35, M weight = 41.7 kg ±7.85kg, and an experimental group (E.Gr.: M age = 11.7 ±0.82, M weight = 48.8 kg ±7.90kg. There was an initial testing (I.T. for the two groups with the OptoJump device (MicroGate, 2005 for 3 forms of speed: reaction rate (R.R., running speed (R.S. and motion speed (M.S.. The following 14 training sessions included, for the E.Gr., 13-15 min. speed development exercises; the C.Gr. performed their usual training. The final testing (F.T. was similar for the two groups. Results: The subjects who completed a specific speed training (E.Gr. showed an improvement of the forms of expression of speed compared to those who did not participate in the program (C.Gr.. Conclusions: Conducting a specific training program to develop manifestations of speed at the age of 11-12 is a solution for optimizing the training of young judoka.

  4. Dynamical memory effects in correlated quantum channels

    Science.gov (United States)

    Addis, Carole; Karpat, Göktuǧ; Macchiavello, Chiara; Maniscalco, Sabrina

    2016-09-01

    Memory effects play a fundamental role in the study of the dynamics of open quantum systems. There exist two conceptually distinct notions of memory discussed for quantum channels in the literature. In quantum information theory quantum channels with memory are characterized by the existence of correlations between successive applications of the channel on a sequence of quantum systems. In open quantum systems theory memory effects arise dynamically during the time evolution of quantum systems and define non-Markovian dynamics. Here we relate and combine these two different concepts of memory. In particular, we study the interplay between correlations between multiple uses of quantum channels and non-Markovianity as nondivisibility of the t -parametrized family of channels defining the dynamical map.

  5. Objective effect manifestation of pectus excavatum on load-stressed pulmonary function testing: a case report

    Directory of Open Access Journals (Sweden)

    Chan Jason

    2011-12-01

    Full Text Available Abstract Introduction Pectus excavatum is the most common congenital deformity of the anterior chest wall that, under certain conditions, may pose functional problems due to cardiopulmonary compromise and exercise intolerance. Case presentation We present the case of an otherwise physically-adept 21-year-old Chinese sportsman with idiopathic pectus excavatum, whose symptoms manifested only on bearing a loaded body vest and backpack during physical exercise. Corroborative objective evidence was obtained via load-stressed pulmonary function testing, which demonstrated restrictive lung function. Conclusion This report highlights the possible detrimental synergism of thoracic load stress and pectus excavatum on cardiopulmonary function. Thoracic load-stressed pulmonary function testing provides objective evidence in support of such a synergistic relationship.

  6. Manifestation of Chaos in Real Complex Systems: Case of Parkinson's Disease

    CERN Document Server

    Yulmetyev, R M; Hänggi, P; Yulmetyev, Renat M.; Demin, Sergey A.; H\\"{a}nggi, Peter

    2006-01-01

    In this chapter we present a new approach to the study of manifestations of chaos in real complex system. Recently we have achieved the following result. In real complex systems the informational measure of chaotic chatacter (IMC) can serve as a reliable quantitative estimation of the state of a complex system and help to estimate the deviation of this state from its normal condition. As the IMC we suggest the statistical spectrum of the non-Markovity parameter (NMP) and its frequency behavior. Our preliminary studies of real complex systems in cardiology, neurophysiology and seismology have shown that the NMP has diverse frequency dependence. It testifies to the competition between Markovian and non-Markovian, random and regular processes and makes a crossover from one relaxation scenario to the other possible. On this basis we can formulate the new concept in the study of the manifestation of chaoticity. We suggest the statistical theory of discrete non-Markov stochastic processes to calculate the NMP and t...

  7. Algorithmic quantum simulation of memory effects

    Science.gov (United States)

    Alvarez-Rodriguez, U.; Di Candia, R.; Casanova, J.; Sanz, M.; Solano, E.

    2017-02-01

    We propose a method for the algorithmic quantum simulation of memory effects described by integrodifferential evolution equations. It consists in the systematic use of perturbation theory techniques and a Markovian quantum simulator. Our method aims to efficiently simulate both completely positive and nonpositive dynamics without the requirement of engineering non-Markovian environments. Finally, we find that small error bounds can be reached with polynomially scaling resources, evaluated as the time required for the simulation.

  8. Effects of donepezil on behavioural manifestations of thalamic infarction: a single case observation

    Directory of Open Access Journals (Sweden)

    Rodrigo eRiveros

    2011-03-01

    Full Text Available Objective: To examine the effect of donepezil for the treatment of cognitive and behavioural disorders associated with thalamic lesions in a 45 years old male who suffered an infarct in the left thalamus. Background: Recent studies suggest that donepezil may improve executive functions impairments due to subcortical ischemic lesionsMethod: The crossover effects of donepezil were analyzed in a single case of thalamic infarction with cognitive and behavioural alterations. Results: Significant behavioural modifications related to improved performances in executive functions were observed with the treatment. Conclusions: The results suggest that donepezil may have significant effect on executive functions that can alter behavioural outcomes after thalamic infarctions

  9. Manifestation of New Interference Effects in a Superconductor-Ferromagnet Spin Valve

    Science.gov (United States)

    Leksin, P. V.; Garif'Yanov, N. N.; Garifullin, I. A.; Schumann, J.; Kataev, V.; Schmidt, O. G.; Büchner, B.

    2011-02-01

    Superconductor-ferromagnet (S/F) spin valve effect theories based on the S/F proximity phenomenon assume that the superconducting transition temperature Tc of F1/F2/S or F1/S/F2 trilayers for parallel magnetizations of the F1 and F2 layers (TcP) are smaller than for the antiparallel orientations (TcAP). Here, we report for CoOx/Fe1/Cu/Fe2/In multilayers with varying Fe2-layer thickness the sign-changing oscillating behavior of the spin valve effect ΔTc=TcAP-TcP. We observe the full direct effect with TcAP>TcP for Fe2-layer thickness dFe2<1nm and the full inverse (TcAPeffect for dFe2≥1nm. Interference of Cooper pair wave functions reflected from both surfaces of the Fe2 layer appear as the most probable reason for the observed behavior of ΔTc.

  10. Influence of certain factors on the manifestations of the adverse effects of metrizamide myelography

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Y.L.; Du Boulay, G.H.; Paul, E.

    1986-07-01

    Although metrizamide is now being superseded by other contrast media, the mechanisms of its side effects may be of fundamental importance. One hundered and four consecutive patients with suspected cervical cord or root lesion were studied prospectively for factors which might influence the side effects of metrizamide myelography. Elderly patients were more prone to develop mental confusion. An earlier onset of dizziness and/or vertigo was associated with the lumbar route of intrathecal injection. Perhaps surprisingly, phenobarbitone prophylaxis shortened the duration of confusion and delayed the onset of headaches. Other factors, viz. sex, excess intracranial flow of metrizamide and myelographic blockage were not shown to have a signifiant influence on the adverse reactions.

  11. Effect of camphor essential oil on rat cerebral cortex activity as manifested by fractal dimension changes

    Directory of Open Access Journals (Sweden)

    Grbić G.

    2008-01-01

    Full Text Available The aim of our study was to investigate the effect of camphor essential oil on rat cerebral cortex activity by fractal analysis. Fractal dimension (FD values of the parietal electrocortical activity were calculated before and after intra-peritoneal administration of camphor essential oil (450-675 μl/kg in anesthetized rats. Camphor oil induced seizure-like activity with single and multiple spiking of high amplitudes in the parietal electrocorticogram and occasional clonic limb convulsions. The FD values of cortical activity after camphor oil administration increased on the average. Only FD values of cortical ECoG sequences were lower than those before camphor oil administration.

  12. Manifestation of the rotational Doppler effect by use of an off-axis optical vortex beam.

    Science.gov (United States)

    Basistiy, I V; Slyusar, V V; Soskin, M S; Vasnetsov, M V; Bekshaev, A Ya

    2003-07-15

    We report what is to our knowledge the first all-optical detection of the frequency beats between Gaussian and Laguerre-Gaussian LG0(1) modes in their axial superposition, caused by the rotational Doppler effect. The relation between the observable off-axis optical vortex rotation and the rotational frequency shift of the Laguerre-Gaussian component is ascertained. The results can be used as a physical basis for recognition of Laguerre-Gaussian mode spectra along their orbital angular momenta.

  13. Photorefractive effects in ferroelectrics as manifestation of structural violations on mesoscales

    CERN Document Server

    Kanaev, I F

    1998-01-01

    The nature of violations in ferroelectric structures that lead to the emergence of direct photocurrents without application of external fields is discussed. We suppose that the main role in transfer processes and photovoltaic effect $9 emergence belongs to macro- and meso-scopic inhomogeneities of the crystal. The boundaries between fairly perfect crystallites have the size of several constants of the crystal lattice and strongly changes the group (pyro-, piezo-, $9 and ferroelectric) properties of the crystal. The presence of inhomogeneities and local electric fields in them determines the charge transfer mechanism: affected by light, the electrons are generated in discretely distributed defect $9 regions and transported from one inhomogeneity to another taking into account the magnitude and sign of the held. In the framework of new concepts, experimental data on recording of the shifted and nonshifted holograms in LiNbO /sub $9 3/ crystals are analyzed. (8 refs).

  14. Incorporation of memory effects in coarse-grained modeling via the Mori-Zwanzig formalism

    Science.gov (United States)

    Li, Zhen; Bian, Xin; Li, Xiantao; Karniadakis, George Em

    2015-12-01

    The Mori-Zwanzig formalism for coarse-graining a complex dynamical system typically introduces memory effects. The Markovian assumption of delta-correlated fluctuating forces is often employed to simplify the formulation of coarse-grained (CG) models and numerical implementations. However, when the time scales of a system are not clearly separated, the memory effects become strong and the Markovian assumption becomes inaccurate. To this end, we incorporate memory effects into CG modeling by preserving non-Markovian interactions between CG variables, and the memory kernel is evaluated directly from microscopic dynamics. For a specific example, molecular dynamics (MD) simulations of star polymer melts are performed while the corresponding CG system is defined by grouping many bonded atoms into single clusters. Then, the effective interactions between CG clusters as well as the memory kernel are obtained from the MD simulations. The constructed CG force field with a memory kernel leads to a non-Markovian dissipative particle dynamics (NM-DPD). Quantitative comparisons between the CG models with Markovian and non-Markovian approximations indicate that including the memory effects using NM-DPD yields similar results as the Markovian-based DPD if the system has clear time scale separation. However, for systems with small separation of time scales, NM-DPD can reproduce correct short-time properties that are related to how the system responds to high-frequency disturbances, which cannot be captured by the Markovian-based DPD model.

  15. Incorporation of memory effects in coarse-grained modeling via the Mori-Zwanzig formalism

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhen; Bian, Xin; Karniadakis, George Em, E-mail: george-karniadakis@brown.edu [Division of Applied Mathematics, Brown University, Providence, Rhode Island 02912 (United States); Li, Xiantao [Department of Mathematics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2015-12-28

    The Mori-Zwanzig formalism for coarse-graining a complex dynamical system typically introduces memory effects. The Markovian assumption of delta-correlated fluctuating forces is often employed to simplify the formulation of coarse-grained (CG) models and numerical implementations. However, when the time scales of a system are not clearly separated, the memory effects become strong and the Markovian assumption becomes inaccurate. To this end, we incorporate memory effects into CG modeling by preserving non-Markovian interactions between CG variables, and the memory kernel is evaluated directly from microscopic dynamics. For a specific example, molecular dynamics (MD) simulations of star polymer melts are performed while the corresponding CG system is defined by grouping many bonded atoms into single clusters. Then, the effective interactions between CG clusters as well as the memory kernel are obtained from the MD simulations. The constructed CG force field with a memory kernel leads to a non-Markovian dissipative particle dynamics (NM-DPD). Quantitative comparisons between the CG models with Markovian and non-Markovian approximations indicate that including the memory effects using NM-DPD yields similar results as the Markovian-based DPD if the system has clear time scale separation. However, for systems with small separation of time scales, NM-DPD can reproduce correct short-time properties that are related to how the system responds to high-frequency disturbances, which cannot be captured by the Markovian-based DPD model.

  16. Incorporation of memory effects in coarse-grained modeling via the Mori-Zwanzig formalism.

    Science.gov (United States)

    Li, Zhen; Bian, Xin; Li, Xiantao; Karniadakis, George Em

    2015-12-28

    The Mori-Zwanzig formalism for coarse-graining a complex dynamical system typically introduces memory effects. The Markovian assumption of delta-correlated fluctuating forces is often employed to simplify the formulation of coarse-grained (CG) models and numerical implementations. However, when the time scales of a system are not clearly separated, the memory effects become strong and the Markovian assumption becomes inaccurate. To this end, we incorporate memory effects into CG modeling by preserving non-Markovian interactions between CG variables, and the memory kernel is evaluated directly from microscopic dynamics. For a specific example, molecular dynamics (MD) simulations of star polymer melts are performed while the corresponding CG system is defined by grouping many bonded atoms into single clusters. Then, the effective interactions between CG clusters as well as the memory kernel are obtained from the MD simulations. The constructed CG force field with a memory kernel leads to a non-Markovian dissipative particle dynamics (NM-DPD). Quantitative comparisons between the CG models with Markovian and non-Markovian approximations indicate that including the memory effects using NM-DPD yields similar results as the Markovian-based DPD if the system has clear time scale separation. However, for systems with small separation of time scales, NM-DPD can reproduce correct short-time properties that are related to how the system responds to high-frequency disturbances, which cannot be captured by the Markovian-based DPD model.

  17. Effects of He-Ne laser on Daphnia magna Straus manifested in subsequent generations

    Science.gov (United States)

    Vorob'yeva, O. V.; Filenko, O. F.; Isakova, E. F.; Vorobieva, N. N.; Rybaltovskii, A. O.; Yusupov, V. I.; Bagratashvili, V. N.

    2015-11-01

    The effects of He-Ne laser irradiation (including visible laser light 632.8 nm in wavelength and an attendant electromagnetic field from the laser apparatus) on the fertility, newborn quality and linear dimensions of the body of Cladocera Daphnia magna Straus were determined. It is shown that the attendant electromagnetic field generated by the laser apparatus can have significant impact on the results of low-intensity laser therapy. The laser light exposure of daphnia to a dose range of 1.7-1300 mJ cm-2 stimulates the integral functions of the daphnia’s body. At the same time, the attendant electromagnetic field (72 mA m-1 in the frequency range of 0.02-20 kHz and 400 mA m-1 in the frequency range of 3-4 MHz) causes the appearance of quickly dying and/or abnormal newborn (up to a small percent) that has never been observed in the control. Anomalies of daphnia mainly consisted of swimming antenna pathologies. Moreover, under the influence of the attendant electromagnetic field on parental daphnia only, these anomalies appear even in several subsequent generations of newborn. The negative impact on daphnia disappears completely after the suppression of the attendant electromagnetic field to laboratory background level. It is shown that laser light can partially compensate the negative impact of the attendant electromagnetic field on Daphnia.

  18. Evaluation of effectiveness of sojourn in a health center of miners with cardiovascular pathology and residual manifestation of craniocerebral trauma

    Energy Technology Data Exchange (ETDEWEB)

    Davydova, N.N.; Nirenburg, K.G.; Kokorina, N.P.; Dyatlova, L.A.; Anikin, B.S.; Pokhlenko, V.B.; Belyaeva, N.G. (Meditsinskii Institut, Kemerovo (USSR))

    1989-02-01

    Evaluates effectiveness of the sojourn in a health center using standard methods of treatment and diet therapy of underground miners of the Kuzbass with early forms of arterial hypertension and manifestations of craniocerebral trauma. Miners were divided into three groups: (1) with hypertension; (2) with neuro-circulatory dystonia; and (3) with craniocerebral trauma. During 24 days at health center, groups 1 and 2 received sedatives, hypertensive medicines and physiotherapy, group 3 biostimulators and dehydrogenating preparations. Changes in conditions of patients were observed. Using the mathematical approach of Markov chains and the method of discrimination of samples to evaluate changes in arterial pressure, stroke volume of blood, pulse, latent period of visual-motor reactions, stability of understanding, and other tests of physiologic status of miners before and after treatment, investigators concluded that a stay in a health center is effective for miners suffering from cardiovascular pathology and mild cerebrocranil trauma under 40 years of age and with an underground work period of less than 10 years. For underground miners suffering cardiovascular pathology and cerebral trauma over 40 years of age and more than 10 years working underground, treatment in a health center at least twice a year is necessary. 5 refs.

  19. Memory-keeping effects and forgetfulness in the dynamics of a qubit coupled to a spin chain

    CERN Document Server

    Apollaro, T J G; Plastina, F; Paternostro, M

    2010-01-01

    Using recently proposed measures for non-Markovianity [H. P. Breuer, E. M. Laine, and J. Piilo, Phys. Rev. Lett. {\\bf 103}, 210401 (2009)], we study the dynamics of a qubit coupled to a spin environment via an energy-exchange mechanism. We show the existence of a point, in the parameter space of the system, where the qubit dynamics is effectively Markovian and that such a point separates two regions with completely different dynamical behaviors. Indeed, our study demonstrates that the qubit evolution can in principle be tuned from a perfectly forgetful one to a deep non-Markovian regime where the qubit is strongly affected by the dynamical back-action of the environmental spins. By means of quantum process tomography, we provide a complete and intuitive characterization of the qubit channel.

  20. Cardiovascular manifestations of phaeochromocytoma

    NARCIS (Netherlands)

    Prejbisz, A.; Lenders, J.W.M.; Eisenhofer, G.; Januszewicz, A.

    2011-01-01

    Clinical expression of phaeochromocytoma may involve numerous cardiovascular manifestations, but usually presents as sustained or paroxysmal hypertension associated with other signs and symptoms of catecholamine excess. Most of the life-threatening cardiovascular manifestations of phaeochromocytoma,

  1. Cardiovascular manifestations of phaeochromocytoma

    NARCIS (Netherlands)

    Prejbisz, A.; Lenders, J.W.M.; Eisenhofer, G.; Januszewicz, A.

    2011-01-01

    Clinical expression of phaeochromocytoma may involve numerous cardiovascular manifestations, but usually presents as sustained or paroxysmal hypertension associated with other signs and symptoms of catecholamine excess. Most of the life-threatening cardiovascular manifestations of phaeochromocytoma,

  2. THE UV/BLUE EFFECTS OF SPACE WEATHERING MANIFESTED IN S-COMPLEX ASTEROIDS. I. QUANTIFYING CHANGE WITH ASTEROID AGE

    Energy Technology Data Exchange (ETDEWEB)

    Vilas, Faith [MMT Observatory, Tucson, AZ (United States); Hendrix, Amanda R., E-mail: fvilas@psi.edu [Planetary Science Institute, 1700 E. Fort Lowell Rd., Suite 106, Tucson, AZ 85719 (United States)

    2015-08-15

    Evidence for the manifestation of space weathering in S-complex asteroids as a bluing of the UV/blue reflectance spectrum is extended using high resolution CCD reflectance spectra of 21 main-belt, 1 Mars-crossing, and 3 near-Earth asteroids covering a wavelength range of 320–620 nm. Demonstration of the transition of iron-bearing materials from volume scattering to surface (Fresnel) scattering is apparent as an abrupt downturn at wavelengths just short of 400 nm in reflectance spectra of fresh asteroid surfaces. The weathering away of this downturn is demonstrated by its absence in reflectance spectra of mature S-complex asteroids, consistent with an increase in npFe{sup 0} on the material's surface. Modeling of the effects of the addition of small amounts of npFe{sup 0} to particles from both a hypothetical mineral and a terrestrial basalt shows that evidence of the addition of 0.0001% npFe{sup 0} affects the reflectance at UV/blue wavelengths, while the addition of 0.01% is required to see the visible/near-infrared reddening and diminution of absorption features. Thus, the UV/blue reflectance characteristics allow earlier detection of the onset of space weathering effects. Combining UV/blue spectral characteristics of asteroids and ordinary chondrite meteorites with estimated ages of the young Datura family, we establish a method of dating asteroid surface ages during the early stages of space weathering. We demonstrate by dating the surface of NEA 163249 2002 GT to be 109 (±18) to 128 (±10) Kyr.

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

    Science.gov (United States)

    Pradhan, Vandana; Nadkar, Milind; Rajadhyaksha, Anjali; Patwardhan, Manisha; Ghosh, Kanjaksha K.; Nadkarni, Anita H.

    2014-01-01

    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. PMID:25548434

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

    Directory of Open Access Journals (Sweden)

    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.

  5. MANIFESTATION OF THE EFFECT OF CRYOSELECTION IN CARP OFFSPRINGS OBTAINED FROM DEFROSTED SPERM SUSPENSION WITH MODIFIED CRYOPROTECTIVE SOLUTIONS

    Directory of Open Access Journals (Sweden)

    V. Cherepnin

    2016-09-01

    Full Text Available Purpose. The purpose of these studies was to evaluate the effect of the cryoselection of carp sperm of multiple age groups depending on the quality of thawed sperm after modification of the composite cryoprotective medium, which was used for the dilution of native sperm before freezing. Methodology. Coenzyme B12 (cobamamide, blood plasma of Prussian carp (Carassius gibelio, which was subjected to natural cold-acclimation, and purified protein antifreeze tmAFP isolated from larval mealworm (Tenebrio molitor, which also was subjected to natural cold-acclimation, were sued as modifiers. Findings. The results of the study demonstrated that qualitative and quantitative characteristics of the defrosted sperm, results of the incubation, rearing of embryos and larvae of Nyvky scaled carp (NLC, as well as fish culture parameters of produced young-of-the-year depended from on the composition of cryoprotective medium. The best results were demonstrated for the experimental groups, obtained with the use of the cryoprotective solution supplemented with purified antifreeze protein tmAFP. The larvae obtained from the sperm cryopreserved with the addition of cryoprotective medium TmAFP had better resistance to dehydration, surpassing the experimental groups obtained from the modifiers of Prussian carp plasma and cobamamide. There is a consolidation in the action of the related extracellular cryoprotectors, which were isolated from the cold-resistant organisms. And carp produced with their used demonstrated better performance during their rearing. The fact can be established that the manifestation of cryoselective effect depends on the integrity of sperm hereditary material and does not depend on the effect of extremely low temperatures on the cell membranes. Originality. There were the first experiments, where Prussian carp plasma and antifreeze protein tmAFP were used as extracellular cryoprotectors. Practical value. The modifications of composite

  6. Respiratory manifestations of hypothyroidism

    DEFF Research Database (Denmark)

    Sorensen, Jesper Roed; Winther, Kristian Hillert; Bonnema, Steen Joop

    2016-01-01

    BACKGROUND: Hypothyroidism has been associated with increased pulmonary morbidity and overall mortality. We conducted a systematic review to identify the prevalence and underlying mechanisms of respiratory problems among patients with thyroid insufficiency. METHODS: PubMed and EMBASE databases were...... searched for relevant literature from January 1950 through January 2015 with study eligibility criteria: English-language publications; Adult subclinical or overt hypothyroid patients; Intervention, observational or retrospective studies; and respiratory manifestations. We followed the PRISMA statement......% of newly diagnosed patients with overt hypothyroidism, and demonstrated reversibility following treatment. The evidence for or against a direct effect on pulmonary function was ambiguous. However, each of the above mentioned areas were only dealt with in a limited number of studies. Therefore, we refrain...

  7. From Markovian semigroup to non-Markovian quantum evolution

    Science.gov (United States)

    Chruściński, D.; Kossakowski, A.

    2012-01-01

    We provided a class of legitimate memory kernels leading to completely positive trace-preserving dynamical maps. Our construction is based on a simple normalization procedure. Interestingly, when applied to a classical system it gives rise to semi-Markov evolution. Therefore, it may be considered as a quantum version of semi-Markov dynamics which is much more general than Markovian dynamics.

  8. From Markovian semigroup to non-Markovian quantum evolution

    CERN Document Server

    Chruscinski, Dariusz

    2010-01-01

    We provided a class of legitimate memory kernels leading to completely positive trace preserving dynamical maps. Our construction is based on a simple normalization procedure. Interestingly, when applied to the celebrated Wigner-Weisskopf theory it gives the standard Markovian evolution governed by the local master equation.

  9. Dynamics of non-Markovian open quantum systems

    Science.gov (United States)

    de Vega, Inés; Alonso, Daniel

    2017-01-01

    Open quantum systems (OQSs) cannot always be described with the Markov approximation, which requires a large separation of system and environment time scales. An overview is given of some of the most important techniques available to tackle the dynamics of an OQS beyond the Markov approximation. Some of these techniques, such as master equations, Heisenberg equations, and stochastic methods, are based on solving the reduced OQS dynamics, while others, such as path integral Monte Carlo or chain mapping approaches, are based on solving the dynamics of the full system. The physical interpretation and derivation of the various approaches are emphasized, how they are connected is explored, and how different methods may be suitable for solving different problems is examined.

  10. Non-Markovian State-Dependent Networks in Critical Loading

    Science.gov (United States)

    2015-02-04

    waiting times. Queueing Syst. Theory Appl. 1990, 6, 335–351. 21. Yamada, K. Diffusion approximation for open state-dependent queueing networks in the heavy...Critical Loading We establish a heavy traffic limit theorem for the queue -length process in a critically loaded single class queueing network with state...Title We establish a heavy traffic limit theorem for the queue -length process in a critically loaded single class queueing network with state

  11. Non-Markovian quantum feedback networks II: Controlled flows

    Science.gov (United States)

    Gough, John E.

    2017-06-01

    The concept of a controlled flow of a dynamical system, especially when the controlling process feeds information back about the system, is of central importance in control engineering. In this paper, we build on the ideas presented by Bouten and van Handel [Quantum Stochastics and Information: Statistics, Filtering and Control (World Scientific, 2008)] and develop a general theory of quantum feedback. We elucidate the relationship between the controlling processes, Z, and the measured processes, Y, and to this end we make a distinction between what we call the input picture and the output picture. We should note that the input-output relations for the noise fields have additional terms not present in the standard theory but that the relationship between the control processes and measured processes themselves is internally consistent—we do this for the two main cases of quadrature measurement and photon-counting measurement. The theory is general enough to include a modulating filter which post-processes the measurement readout Y before returning to the system. This opens up the prospect of applying very general engineering feedback control techniques to open quantum systems in a systematic manner, and we consider a number of specific modulating filter problems. Finally, we give a brief argument as to why most of the rules for making instantaneous feedback connections [J. Gough and M. R. James, Commun. Math. Phys. 287, 1109 (2009)] ought to apply for controlled dynamical networks as well.

  12. Data-driven non-Markovian closure models

    Science.gov (United States)

    Kondrashov, Dmitri; Chekroun, Mickaël D.; Ghil, Michael

    2015-03-01

    This paper has two interrelated foci: (i) obtaining stable and efficient data-driven closure models by using a multivariate time series of partial observations from a large-dimensional system; and (ii) comparing these closure models with the optimal closures predicted by the Mori-Zwanzig (MZ) formalism of statistical physics. Multilayer stochastic models (MSMs) are introduced as both a generalization and a time-continuous limit of existing multilevel, regression-based approaches to closure in a data-driven setting; these approaches include empirical model reduction (EMR), as well as more recent multi-layer modeling. It is shown that the multilayer structure of MSMs can provide a natural Markov approximation to the generalized Langevin equation (GLE) of the MZ formalism. A simple correlation-based stopping criterion for an EMR-MSM model is derived to assess how well it approximates the GLE solution. Sufficient conditions are derived on the structure of the nonlinear cross-interactions between the constitutive layers of a given MSM to guarantee the existence of a global random attractor. This existence ensures that no blow-up can occur for a broad class of MSM applications, a class that includes non-polynomial predictors and nonlinearities that do not necessarily preserve quadratic energy invariants. The EMR-MSM methodology is first applied to a conceptual, nonlinear, stochastic climate model of coupled slow and fast variables, in which only slow variables are observed. It is shown that the resulting closure model with energy-conserving nonlinearities efficiently captures the main statistical features of the slow variables, even when there is no formal scale separation and the fast variables are quite energetic. Second, an MSM is shown to successfully reproduce the statistics of a partially observed, generalized Lotka-Volterra model of population dynamics in its chaotic regime. The challenges here include the rarity of strange attractors in the model's parameter space and the existence of multiple attractor basins with fractal boundaries. The positivity constraint on the solutions' components replaces here the quadratic-energy-preserving constraint of fluid-flow problems and it successfully prevents blow-up.

  13. Characterization of the degree of Musical non-Markovianity

    OpenAIRE

    Mannone, Maria; Compagno, Giuseppe

    2013-01-01

    Recently, as an aid for musical analysis, in computational musicology mathematical and informatics tools have been developed to quantitatively characterize some aspects of musical compositions. To a musical composition can be attributed by ear a certain amount of memory. This results associated to repetitions and similarities of the patterns in musical scores. To higher variations, a lower amount of memory is perceived. However musical memory of a score has never been quantitatively defined. ...

  14. Non-Markovian State-Dependent Networks in Critical Loading

    Science.gov (United States)

    2013-01-23

    Stochastics Rep., 40(1-2):43–76, 1992. [11] T. G. Kurtz. Strong approximation theorems for density dependent Markov chains . Stochastic Processes Appl., 6(3...for queue -length processes in critically loaded single class queueing networks with state-dependent arrival and service rates. A distinguishing...loading Report Title ABSTRACT We establish heavy traffic limit theorems for queue -length processes in critically loaded single class queueing networks

  15. PARANEOPLASTIC MANIFESTATIONS IN CHILDREN

    NARCIS (Netherlands)

    DEGRAAF, JH; TAMMINGA, RYJ; KAMPS, WA

    1994-01-01

    Paraneoplastic manifestations are signs and symptoms observed in patients with cancer, distant from the tumour or its metastases and not caused by invasion, obstruction or bulk mass. In children with cancer, paraneoplastic manifestations are rare and distinct from those observed in adults. Knowledge

  16. Atypical manifestations of leptospirosis.

    Science.gov (United States)

    Rajapakse, Senaka; Rodrigo, Chaturaka; Balaji, Krishan; Fernando, Sumadhya Deepika

    2015-05-01

    Leptospirosis is an illness with a wide spectrum of clinical manifestations and severe illness affects nearly all organ systems. Serious and potentially life-threatening clinical manifestations of acute leptospirosis are caused by both direct tissue invasion by spirochaetes and by the host immune responses. In its severe form, leptospirosis can cause multi-organ dysfunction and death in a matter of days. Therefore it is critical to suspect and recognize the disease early, in order to initiate timely treatment. While the classical presentation of the disease is easily recognized by experienced clinicians practising in endemic regions, rarer manifestations can be easily missed. In this systematic review, we summarize the atypical manifestations reported in literature in patients with confirmed leptospirosis. Awareness of these unusual manifestations would hopefully guide clinicians towards early diagnosis.

  17. Parasitic Diseases With Cutaneous Manifestations.

    Science.gov (United States)

    Ash, Mark M; Phillips, Charles M

    2016-01-01

    Parasitic diseases result in a significant global health burden. While often thought to be isolated to returning travelers, parasitic diseases can also be acquired locally in the United States. Therefore, clinicians must be aware of the cutaneous manifestations of parasitic diseases to allow for prompt recognition, effective management, and subsequent mitigation of complications. This commentary also reviews pharmacologic treatment options for several common diseases.

  18. Effect of HLA-B*27 and its subtypes on clinical manifestations and severity of ankylosing spondylitis in Iranian patients.

    Directory of Open Access Journals (Sweden)

    Sasan Fallahi

    2013-12-01

    Full Text Available The aim of this study was to assess the role of HLA-B*27 and it's subtypes in determining severity and clinical manifestations of ankylosing spondylitis (AS.A total of 163 AS patients were assessed for clinical manifestations and severity using structured questionnaires. HLA-B*27 screening and B*27 sub-typing were performed by PCR.One hundred twenty two patients (74.8% were B*27 positive. The male to female ratio, peripheral arthritis, steroid use, intense dorsal kyphosis and decrease of cervical slope had a significantly higher frequency in B*27 positive patients compared to B*27 negative ones (p=0.01, 0.001, 0.01, 0.04 and 0.04, respectively. However, the age of diagnosis was significantly lower in B*27 positive patients (p=0.005. Trend in uveitis and some severity markers including: BASMI and ASQoL were toward higher values in B*27 positive group with no significant difference. After controlling confounding variables, significant relationship was found only between B*27 and BASMI (p=0.01. B*27 subtypes in patients were included B*2705: 48.4%, B*2702: 42.6%, B*2704: 5.7% and B*2707: 3.3%. No significant differences were seen for severity markers and clinical manifestations between subtypes; although trend toward lower values of severity markers, less intense dorsal kyphosis and less decrease of cervical slope were observed in B*2704 and B*2707 versus other polymorphisms.Clinical features and severity of AS is influenced by HLA-B*27. Trend toward higher severity markers in B*2705 and B*2702 versus other polymorphisms might be subject of interest for evaluation in other ethnicities with concentration to other novel susceptibility genes co-inherited in each B*27 subtype.

  19. Towards Developing Systematics for Using Periodic Studies of the Hydrothermal Manifestations as Effective Tool for Monitoring Largely 'inaccessible' Volcanoes

    Science.gov (United States)

    Alam, M.

    2010-12-01

    The San José and Tupungatito volcanoes, located near Santiago (Chile), are the potential hazards, given their geological and historical record of explosive eruptions with pyroclastic flows, most recently in 1960 and 1987 respectively (Global Volcanism Program, Smithsonian Institution). What aggravates the potential risk of these very high (>5290m elevation) snow- and ice-covered volcanoes is their location at the source of relatively narrow mountain drainage systems that feed into the Maipo River, flowing through the southern outskirts of Santiago. Sector-collapse and debris-flow, as a result of volcano-ice/snow interaction, can form lahars causing immense destruction to the life and property in the Maipo Valley (Cajón del Maipo). These lahars can cause submergence and burial of vast downstream areas under several meters thick sediment, as in the case of 1980 eruption of Mount St. Helens, USA. In the event of a major eruption, Santiago city will be at peril, with all the drinking water supply installations either destroyed or contaminated to the extent of being abandoned. Besides, ash and tephra will halt the air traffic in the region, particularly in Santiago-Mendoza sector between Chile and Argentina. In a proposed research project (for which funding is awaited from CONICYT, Chile under its Initiation into Research Funding Competition), hydrothermal systems associated with the aforementioned volcanoes will be periodically studied to monitor these volcanoes, in order to develop a Systematics for using the peripheral hydrothermal manifestations, together with nearby surface water bodies, as means for monitoring the activities of the volcano(es). Basic premise of this proposal is to use the relationship between volcanic and hydrothermal activities. Although this association has been observed at many volcanic centers, no attempt has been made to use this relation effectively as a tool for monitoring the volcanoes. Before an eruption or even with increased

  20. Ocular manifestations of candidemia

    NARCIS (Netherlands)

    Oude Lashof, A.M.L.; Rothova, A.; Sobel, J.D.; Ruhnke, M.; Pappas, P.G.; Viscoli, C.; Schlamm, H.T.; Oborska, I.T.; Rex, J.H.; Kullberg, B.J.

    2011-01-01

    BACKGROUND: Ocular candidiasis is a major complication of candidemia. The incidence, risk factors, and outcome of eye involvement during candidemia are largely unknown. We prospectively studied the ocular manifestations of candidemia in a large, worldwide, randomized multicenter trial that compared

  1. Cardiovascular manifestations in hyperthyroidism

    Directory of Open Access Journals (Sweden)

    Vairamani Kandan

    2016-07-01

    Conclusions: This study shows that cardiovascular manifestations are quite common and varied in hyperthyroidism which are to be looked for in the management. [Int J Res Med Sci 2016; 4(7.000: 3032-3038

  2. Haematological manifestations of lupus

    Science.gov (United States)

    Fayyaz, Anum; Igoe, Ann; Kurien, Biji T; Danda, Debashish; James, Judith A; Stafford, Haraldine A; Scofield, R Hal

    2015-01-01

    Our purpose was to compile information on the haematological manifestations of systemic lupus erythematosus (SLE), namely leucopenia, lymphopenia, thrombocytopenia, autoimmune haemolytic anaemia (AIHA), thrombotic thrombocytopenic purpura (TTP) and myelofibrosis. During our search of the English-language MEDLINE sources, we did not place a date-of-publication constraint. Hence, we have reviewed previous as well as most recent studies with the subject heading SLE in combination with each manifestation. Neutropenia can lead to morbidity and mortality from increased susceptibility to infection. Severe neutropenia can be successfully treated with granulocyte colony-stimulating factor. While related to disease activity, there is no specific therapy for lymphopenia. Severe lymphopenia may require the use of prophylactic therapy to prevent select opportunistic infections. Isolated idiopathic thrombocytopenic purpura maybe the first manifestation of SLE by months or even years. Some manifestations of lupus occur more frequently in association with low platelet count in these patients, for example, neuropsychiatric manifestation, haemolytic anaemia, the antiphospholipid syndrome and renal disease. Thrombocytopenia can be regarded as an important prognostic indicator of survival in patients with SLE. Medical, surgical and biological treatment modalities are reviewed for this manifestation. First-line therapy remains glucocorticoids. Through our review, we conclude glucocorticoids do produce a response in majority of patients initially, but sustained response to therapy is unlikely. Glucocorticoids are used as first-line therapy in patients with SLE with AIHA, but there is no conclusive evidence to guide second-line therapy. Rituximab is promising in refractory and non-responding AIHA. TTP is not recognised as a criteria for classification of SLE, but there is a considerable overlap between the presenting features of TTP and SLE, and a few patients with SLE have concurrent

  3. Haematological manifestations of lupus.

    Science.gov (United States)

    Fayyaz, Anum; Igoe, Ann; Kurien, Biji T; Danda, Debashish; James, Judith A; Stafford, Haraldine A; Scofield, R Hal

    2015-01-01

    Our purpose was to compile information on the haematological manifestations of systemic lupus erythematosus (SLE), namely leucopenia, lymphopenia, thrombocytopenia, autoimmune haemolytic anaemia (AIHA), thrombotic thrombocytopenic purpura (TTP) and myelofibrosis. During our search of the English-language MEDLINE sources, we did not place a date-of-publication constraint. Hence, we have reviewed previous as well as most recent studies with the subject heading SLE in combination with each manifestation. Neutropenia can lead to morbidity and mortality from increased susceptibility to infection. Severe neutropenia can be successfully treated with granulocyte colony-stimulating factor. While related to disease activity, there is no specific therapy for lymphopenia. Severe lymphopenia may require the use of prophylactic therapy to prevent select opportunistic infections. Isolated idiopathic thrombocytopenic purpura maybe the first manifestation of SLE by months or even years. Some manifestations of lupus occur more frequently in association with low platelet count in these patients, for example, neuropsychiatric manifestation, haemolytic anaemia, the antiphospholipid syndrome and renal disease. Thrombocytopenia can be regarded as an important prognostic indicator of survival in patients with SLE. Medical, surgical and biological treatment modalities are reviewed for this manifestation. First-line therapy remains glucocorticoids. Through our review, we conclude glucocorticoids do produce a response in majority of patients initially, but sustained response to therapy is unlikely. Glucocorticoids are used as first-line therapy in patients with SLE with AIHA, but there is no conclusive evidence to guide second-line therapy. Rituximab is promising in refractory and non-responding AIHA. TTP is not recognised as a criteria for classification of SLE, but there is a considerable overlap between the presenting features of TTP and SLE, and a few patients with SLE have concurrent

  4. [Unusual Migraine Manifestations].

    Science.gov (United States)

    Schipper, Sivan; Gantenbein, Andreas R; Sandor, Peter S

    2016-06-01

    Migraine is a complex neurologic disorder by which several systems of the central nervous system (autonomous system, affective, cognitive, sensoric and motoric system) may be affected on different levels. Around a fourth of the patients have migraine aura. The most common aura is the visual aura, followed by sensoric aura. But motoric deficits as well as deficits of higher cortical centers (disorders of thinking, orientation, coherence or concentration) may occur as well. In analogy with a headache calendar, an aura calendar can deliver important help in the diagnostic process of rare migraine manifestations and prevent underdiagnosis of unusual migraine manifestations. Complex migraine manifestations are diagnoses of exlusion, and a broad diagnostic work-up is warranted in order to exclude dangerous neurologic pathologies. There are no specific therapeutic recommendations, as there is a lack of randomized controlled studies.

  5. Pulmonary manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Sameer Gulati

    2012-01-01

    Full Text Available Leptospirosis has a spectrum of presentation which ranges from mild disease to a severe form comprising of jaundice and renal failure. Involvement of the lung can vary from subtle clinical features to deadly pulmonary hemorrhage and acute respiratory distress syndrome. Of late, it has been identified that leptospirosis can present atypically with predominant pulmonary manifestations. This can delay diagnosis making and hence optimum treatment. The purpose of this review is to bring together all the reported pulmonary manifestations of leptospirosis and the recent trends in the management.

  6. Emotional face recognition deficits and medication effects in pre-manifest through stage-II Huntington's disease.

    Science.gov (United States)

    Labuschagne, Izelle; Jones, Rebecca; Callaghan, Jenny; Whitehead, Daisy; Dumas, Eve M; Say, Miranda J; Hart, Ellen P; Justo, Damian; Coleman, Allison; Dar Santos, Rachelle C; Frost, Chris; Craufurd, David; Tabrizi, Sarah J; Stout, Julie C

    2013-05-15

    Facial emotion recognition impairments have been reported in Huntington's disease (HD). However, the nature of the impairments across the spectrum of HD remains unclear. We report on emotion recognition data from 344 participants comprising premanifest HD (PreHD) and early HD patients, and controls. In a test of recognition of facial emotions, we examined responses to six basic emotional expressions and neutral expressions. In addition, and within the early HD sample, we tested for differences on emotion recognition performance between those 'on' vs. 'off' neuroleptic or selective serotonin reuptake inhibitor (SSRI) medications. The PreHD groups showed significant (precognition, compared to controls, on fearful, angry and surprised faces; whereas the early HD groups were significantly impaired across all emotions including neutral expressions. In early HD, neuroleptic use was associated with worse facial emotion recognition, whereas SSRI use was associated with better facial emotion recognition. The findings suggest that emotion recognition impairments exist across the HD spectrum, but are relatively more widespread in manifest HD than in the premanifest period. Commonly prescribed medications to treat HD-related symptoms also appear to affect emotion recognition. These findings have important implications for interpersonal communication and medication usage in HD.

  7. Oral Manifestations of Menopause

    African Journals Online (AJOL)

    The oral manifestations may vary for each patient in the form of burning mouth syndrome .... as chlorhexidine aids in reduction of the accumulation of dental plaque.[5,10 ... women with missing teeth may have a higher risk of hypertension and ...

  8. Digestive manifestations of parathyroid disorders

    Institute of Scientific and Technical Information of China (English)

    Bassam Abboud; Ronald Daher; Joe Boujaoude

    2011-01-01

    The parathyroid glands are the main regulator of plasma calcium and have a direct influence on the digestive tract. Parathyroid disturbances often result in unknown long-standing symptoms. The main manifestation of hypoparathyroidism is steatorrhea due to a deficit in exocrine pancreas secretion. The association with celiac sprue may contribute to malabsorption. Hyperparathyroidism causes smooth-muscle atony, with upper and lower gastrointestinal symptoms such as nausea, heartburn and constipation. Hyperparathyroidism and peptic ulcer were strongly linked before the advent of proton pump inhibitors. Nowadays, this association remains likely only in the particular context of multiple endocrine neoplasia type 1/Zollinger-Ellison syndrome. In contrast to chronic pancreatitis, acute pancreatitis due to primary hyperparathyroidism is one of the most studied topics. The causative effect of high calcium level is confirmed and the distinction from secondary hyperparathyroidism is mandatory. The digestive manifestations of parathyroid malfunction are often overlooked and serum calcium level must be included in the routine workup for abdominal symptoms.

  9. Toxoplasmosis and its Ocular Manifestations

    Directory of Open Access Journals (Sweden)

    Koev Kr.

    2014-06-01

    Full Text Available The present review provides general information about the parasitic infection of toxoplasmosis and describes the ways of its transmission. It outlines the importance of the consequences of toxoplasmosis infection and the methods of its prevention. The review traces the harmful effects of the disease on human and animal organisms, the causes and stages of development of the disease. The review specifically focuses on the ocular manifestations of toxoplasmosis which can cause ocular lesions, inflammation and scarring. Herein are described the ways toxoplasmosis can damage the eyes causing chorioretinitis, nystagmus, microphthalmia, etc. Furthermore, the review addresses the problem of how congenital and acquired toxoplasmosis affects eyes. The ocular symptoms of toxoplasmosis include weakened or blurred vision, eyeballs pain, ocular sensitivity to light, etc. The harmful effects of toxoplasmosis to pregnant women and immunocompromised patients have been delineated. Some of the disease manifestations include jaundice, rash, asphyxia, etc. The review traces the diagnostic work-up and comments on common tests for toxoplasmosis, such as taking of blood serum samples. The review ends with the treatment of the disease and of its ocular manifestations in particular, for example application of intravitreous injection. The prevention of the infection is extremely important for pregnant women, immunocompromised patients and patients with AIDS.

  10. Nonlocal memory effects in the dynamics of open quantum systems

    CERN Document Server

    Laine, Elsi-Mari; Piilo, Jyrki; Li, Chuan-Feng; Guo, Guang-Can

    2011-01-01

    We study a model of two entangled photons interacting locally with two dephasing environments. It is shown that initial correlations between the local environments can generate a nonlocal quantum process from a local interaction Hamiltonian. While the global dynamics of the two-photon polarization state exhibits strong memory effects, the induced local dynamics of either of the two photons is found to be Markovian. A direct connection between the degree of memory effects and the amount of correlations in the initial environmental state is derived. The results demonstrate that, contrary to conventional wisdom, enlarging an open system can change the dynamics from Markovian to non-Markovian.

  11. Inflammatory Manifestations of Lymphedema

    Directory of Open Access Journals (Sweden)

    Catherine L. Ly

    2017-01-01

    Full Text Available Lymphedema results from lymphatic insufficiency leading to a progressive inflammatory process that ultimately manifests as discomfort, recurrent infections, and, at times, secondary malignancy. Collectively, these morbidities contribute to an overall poor quality of life. Although there have been recent advances in microsurgical interventions, a conservative palliative approach remains the mainstay of treatment for this disabling disease. The absence of a cure is due to an incomplete understanding of the pathophysiological changes that result in lymphedema. A histological hallmark of lymphedema is inflammatory cell infiltration and recent studies with animal models and clinical biopsy specimens have suggested that this response plays a key role in the pathology of the disease. The purpose of this report is to provide an overview of the ongoing research in and the current understanding of the inflammatory manifestations of lymphedema.

  12. Inflammatory Manifestations of Lymphedema

    Science.gov (United States)

    Ly, Catherine L.; Kataru, Raghu P.; Mehrara, Babak J.

    2017-01-01

    Lymphedema results from lymphatic insufficiency leading to a progressive inflammatory process that ultimately manifests as discomfort, recurrent infections, and, at times, secondary malignancy. Collectively, these morbidities contribute to an overall poor quality of life. Although there have been recent advances in microsurgical interventions, a conservative palliative approach remains the mainstay of treatment for this disabling disease. The absence of a cure is due to an incomplete understanding of the pathophysiological changes that result in lymphedema. A histological hallmark of lymphedema is inflammatory cell infiltration and recent studies with animal models and clinical biopsy specimens have suggested that this response plays a key role in the pathology of the disease. The purpose of this report is to provide an overview of the ongoing research in and the current understanding of the inflammatory manifestations of lymphedema. PMID:28106728

  13. Achondroplasia: manifestations and treatment.

    Science.gov (United States)

    Shirley, Eric D; Ain, Michael C

    2009-04-01

    Achondroplasia, the most common skeletal dysplasia, is caused by a mutation of fibroblast growth factor receptor-3. This disorder is characterized by frontal bossing, midface hypoplasia, otolaryngeal system dysfunction, and rhizomelic short stature. Orthopaedic manifestations are exhibited in the spine and the extremities. In the infant with achondroplasia, foramen magnum stenosis may result in brainstem compression with apnea and sudden death. Thoracolumbar kyphosis is seen in most infants, but typically it resolves when the child begins to walk. Anatomic anomalies of the vertebral column place the patient at risk for spinal stenosis as early as the first decade and especially during adulthood. Radial head dislocation is one manifestation in the upper extremity. Lower extremity alignment often is characterized by genu varum, which may require correction osteotomy. Medical and surgical options are available to increase patient height, but indications are controversial, and treatment often consumes a large portion of the child's life.

  14. Rheumatic manifestations of diabetes mellitus.

    Science.gov (United States)

    Lebiedz-Odrobina, Dorota; Kay, Jonathan

    2010-11-01

    DM is associated with various musculoskeletal manifestations. The strength of this relationship varies among the various musculoskeletal disorders; the associations are based mostly on epidemiologic data. For most of these conditions, definitive pathophysiologic correlates are lacking.Hand and shoulder disorders occur more frequently than other musculoskeletal manifestations of DM. Recognition of the association between DM and shoulder adhesive capsulitis, DD, and stenosing flexor tenosynovitis facilitates their correct diagnosis in the setting of DM and prompt initiation of appropriate treatment, which may include optimizing glycemic control. Conversely, awareness and identification of the characteristic musculoskeletal manifestations of DM may facilitate earlier diagnosis of DM and initiation of glucose-lowering therapy to retard the development of diabetic complications.Much less has been published about the musculoskeletal complications of DM than about its micro- and macrovascular complications. Prospective case-control cohort studies are needed to establish the true prevalence of musculoskeletal complications of DM and the metabolic syndrome, especially in this era of tighter glycemic control.The potential relationship between DM and the development of OA needs to be clarified in large, prospective, case-control cohort studies. The effect on musculoskeletal manifestations of various therapeutic regimens to manage DM should be studied prospectively. Treatment regimens for some musculoskeletal conditions associated with DM, such as DISH, should be studied in larger prospective, randomized,controlled clinical trials.At the molecular level, further studies are warranted to clarify the potential contribution of AGEs and adipokines to the development of OA and diabetic musculoskeletal syndromes, such as shoulder adhesive capsulitis, DD, stenosing flexor tenosynovitis, and LJM. Identification of such molecular targets for therapy would promote the development of

  15. MANIFEST OF DEPTH SOCIOPSYCHOLOGY

    OpenAIRE

    ZELITCHENKO ALEXANDER

    2013-01-01

    The observations of motives of activity of big groups (nations, confessions etc.) as a whole result in discovery of the part of unconscious mind that is common for all members of big group a collective unconscious. Two parts of collective unconscious may be determined: the collective superconscious known first as a group archetype and the collective subconscious, which manifest itself for example in phenomenon of collective trauma. Depth sociopsychology is a science about the collective uncon...

  16. Haematological manifestations of lupus

    OpenAIRE

    2015-01-01

    Our purpose was to compile information on the haematological manifestations of systemic lupus erythematosus (SLE), namely leucopenia, lymphopenia, thrombocytopenia, autoimmune haemolytic anaemia (AIHA), thrombotic thrombocytopenic purpura (TTP) and myelofibrosis. During our search of the English-language MEDLINE sources, we did not place a date-of-publication constraint. Hence, we have reviewed previous as well as most recent studies with the subject heading SLE in combination with each manif...

  17. Orofacial manifestations of achondroplasia

    OpenAIRE

    Kaushik, Atul; Kumar, Munish; Rohilla, Smriti; Tanwar, Renu; V C Vinod

    2012-01-01

    Achondroplasia (Online Mendelian Inheritance in Man [OMIM] 100800), is considered as a form of skeletal dysplasia dwarfism that manifests with stunted stature and disproportionate limb shortening. Achondroplasia is of special interest in the field of dentistry because of its characteristic craniofacial features which include relative macrocephaly, depressed nasal bridge and maxillary hypoplasia. Presence of large head, implanted shunt, airway obstruction and difficulty in head control require...

  18. Ocular manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Rathinam S

    2005-01-01

    Full Text Available Leptospiral uveitis is a common entity in tropical countries. Ocular manifestations are noted in the second phase of illness, but these remain under-diagnosed mainly because of the prolonged symptom-free period that separates the systemic manifestations from detection of ocular manifestations.Varying ophthalmic presentations and the intrinsic nature of different types of uveitis to mimic one another also challenge the accuracy of the diagnosis. Of the individual ocular signs, the combination of acute, non-granulomatous, panuveitis, hypopyon, vasculitis, optic disc edema, membranous vitreous opacities and absence of choroiditis or retinitis have high predictive value for the clinical diagnosis of leptospiral uveitis. Geographic location of the patient, occupation, socio-economic status, risk factors related to exposure, past history of fever or jaundice also aid in diagnosis.Steroids are the mainstay of treatment for leptospiral uveitis. Depending upon the severity and anatomical location of inflammatory lesion, topical, peri-ocular and/or systemic steroids are given. The prognosis is generally good, even when the inflammation is severe.

  19. Conflict-Specific Aging Effects Mainly Manifest in Early Information Processing Stages-An ERP Study with Different Conflict Types.

    Science.gov (United States)

    Korsch, Margarethe; Frühholz, Sascha; Herrmann, Manfred

    2016-01-01

    Aging is usually accompanied by alterations of cognitive control functions such as conflict processing. Recent research suggests that aging effects on cognitive control seem to vary with degree and source of conflict, and conflict specific aging effects on performance measures as well as neural activation patterns have been shown. However, there is sparse information whether and how aging affects different stages of conflict processing as indicated by event related potentials (ERPs) such as the P2, N2 and P3 components. In the present study, 19 young and 23 elderly adults performed a combined Flanker conflict and stimulus-response-conflict (SRC) task. Analysis of the reaction times (RTs) revealed an increased SRC related conflict effect in elderly. ERP analysis furthermore demonstrated an age-related increase of the P2 amplitude in response to the SRC task. In addition, elderly adults exhibited an increased P3 amplitude modulation induced by incongruent SRC and Flanker conflict trials.

  20. MANIFESTATION OF THE EFFECT OF CRYOSELECTION IN CARP OFFSPRINGS OBTAINED FROM DEFROSTED SPERM SUSPENSION WITH MODIFIED CRYOPROTECTIVE SOLUTIONS

    OpenAIRE

    V. Cherepnin

    2016-01-01

    Purpose. The purpose of these studies was to evaluate the effect of the cryoselection of carp sperm of multiple age groups depending on the quality of thawed sperm after modification of the composite cryoprotective medium, which was used for the dilution of native sperm before freezing. Methodology. Coenzyme B12 (cobamamide), blood plasma of Prussian carp (Carassius gibelio), which was subjected to natural cold-acclimation, and purified protein antifreeze tmAFP isolated from larval mealwo...

  1. N-Terminal Peptide Sequence Repetition Influences the Kinetics of Backbone Fragmentation: A Manifestation of the Jahn-Teller Effect?

    Science.gov (United States)

    Good, David M.; Yang, Hongqian; Zubarev, Roman A.

    2013-11-01

    Analysis of large (>10,000 entries) databases consisting of high-resolution tandem mass spectra of peptide dications revealed with high statistical significance ( P diketopiperazine structure for at least some b2 + ions. When consisting of two identical amino acids, these species should form through intermediates that have a symmetric geometry and, thus, must be subject to the Jahn-Teller effect that reduces the stability of such systems.

  2. Clinical manifestations of sleep apnea.

    Science.gov (United States)

    Stansbury, Robert C; Strollo, Patrick J

    2015-09-01

    Obstructive sleep apnea (OSA) may manifest in a number of ways from subtle intrusion into daily life to profound sleepiness, snoring, witnessed apneas and other classic symptoms. Although there is increasing evidence suggesting OSA can adversely affect health in a variety of ways, this disorder remains underdiagnosed. The most well-escribed health consequences of OSA relate to the cardiovascular system. Hypertension and arrhythmias have a strong association with OSA, and evidence suggests that treatment of OSA in patients with refractory hypertension and in patients planning cardioversion for atrial fibrillation may be of particularly importance. Significant associations between heart failure and OSA as well as complex sleep apnea have also been well-described. Cerebrovascular insult, impaired neurocognition, and poorly controlled mood disorder are also associated with in OSA. Therapy for OSA may ameliorate atherosclerotic progression and improve outcomes post-cerebrovascular accident (CVA). OSA should be considered in patients complaining of poor concentration at work, actual or near-miss motor vehicle accidents, and patients with severe sleepiness as a component of their co-morbid mood disorders. The metabolic impact of OSA has also been studied, particularly in relation to glucose homeostasis. Also of interest is the potential impact OSA has on lipid metabolism. The adverse effect untreated OSA has on glucose tolerance and lipid levels has led to the suggestion that OSA is yet another constituent of the metabolic syndrome. Some of these metabolic derangements may be related to the adverse effects untreated OSA has on hepatic health. The cardiovascular, neurocognitive, and metabolic manifestations of OSA can have a significant impact on patient health and quality of life. In many instances, evidence exists that therapy not only improves outcomes in general, but also modifies the severity of co-morbid disease. To mitigate the long-term sequela of this disease

  3. Orientation-dependent changes in MR signal intensity of articular cartilage: a manifestation of the ``magic angle`` effect

    Energy Technology Data Exchange (ETDEWEB)

    Wacker, F.K.; Bolze, X.; Felsenberg, D.; Wolf, K.J. [Department of Radiology, Benjamin Franklin University Hospital, Free University Berlin, D-12200 Berlin (Germany)

    1998-06-01

    Objective: To study magnetic resonance (MR) imaging pattern of normal hyaline articular cartilage in the knee joint with regard to the contribution of the ``magic angle`` effect to the MR signal. Design. Thirty-two healthy volunteers were imaged in a standard supine position in a 1.5-T unit using spin echo and gradient echo sequences. Nine volunteers were reimaged with the knee flexed. The signal behavior of the hyaline cartilage of the femoral condyles was evaluated qualitatively and quantitatively. The extended and flexed positions of the nine volunteers were compared. Results. A superficial and a deep hyperintense layer and a hypointense middle cartilage layer were observed. Segments of increased signal intensity were visible along the condyles; a magic angle effect on signal intensity was evident in the hypointense middle layer with both gradient echo and spin echo images. Conclusion. The MR signal behavior of hyaline cartilage is influenced by the alignment of the collagen fibers within the cartilage in relation to the magnetic field. Failure to recognize this effect may lead to inaccurate diagnosis. (orig.) With 4 figs., 17 refs.

  4. Discourse Manifestation of Personality

    Directory of Open Access Journals (Sweden)

    Владимир Ильич Карасик

    2016-12-01

    Full Text Available The paper deals with approaches to discourse studies. The approaches may be regarded as discourse dimensions associated with models presented and substantiated by M.M. Bakhtin, J. Habermas, Yu.M. Lotman and M.A.K. Halliday. They comprise contents, participants, tonality, channel and communicative actions. The approaches described complement each other and make it possible to synthesize the results achieved in Text Linguistics, Pragmatics, Social Linguistics, and Discourse Studies. They are joined by and oriented towards the concept of Language Personality, i.e. persons who manifest themselves in various kinds of communicative situations. However, each discourse dimension corresponds to a certain type of discourse. A Topic Approach to discourse focuses upon its contents (its referential substance and specifies the correlation between explicit and implicit meaning expression. A Subject Approach to discourse makes it possible to single out and describe two basic types of communication as presented in Personality bound and Status bound discourse, the former diverges into two subtypes - Habitual and Existential communication, whereas the latter is manifested in various kinds of Institutional discourse. A Tonality Approach to discourse highlights different types of stylistic and emotional modes of communication and correspondingly characterizes personality types who are engaged in such situations. A Regime Approach is concentrated on communication channel and technical peculiarities of behavior determined by those restrictions. An Action Approach to discourse gives us a broader understanding of a performative act, i.e. an action incorporated in culture and a situational behavioral interaction.

  5. Rheumatologic Manifestations of Sarcoidosis

    Science.gov (United States)

    Sweiss, Nadera J.; Patterson, Karen; Sawaqed, Ray; Jabbar, Umair; Korsten, Peter; Hogarth, Kyle; Wollman, Robert; Garcia, Joe G.N.; Niewold, Timothy B.; Baughman, Robert P.

    2012-01-01

    Sarcoidosis is a systemic, clinically heterogeneous disease characterized by the development of granulomas. Any organ system can be involved, and patients may present with any number of rheumatologic symptoms. There are no U.S. Food and Drug Administration–approved therapies for the treatment of sarcoidosis. Diagnosing sarcoidosis becomes challenging, particularly when its complications cause patients’ symptoms to mimic other conditions, including polymyositis, Sjögren syndrome, or vasculitis. This review presents an overview of the etiology of and biomarkers associated with sarcoidosis. We then provide a detailed description of the rheumatologic manifestations of sarcoidosis and present a treatment algorithm based on current clinical evidence for patients with sarcoid arthritis. The discussion will focus on characteristic findings in patients with sarcoid arthritis, osseous involvement in sarcoidosis, and sarcoid myopathy. Arthritic conditions that sometimes coexist with sarcoidosis are described as well. We present two cases of sarcoidosis with rheumatologic manifestations. Our intent is to encourage a multidisciplinary, translational approach to meet the challenges and difficulties in understanding and treating sarcoidosis. PMID:20665396

  6. Hematologic manifestations of babesiosis.

    Science.gov (United States)

    Akel, Tamer; Mobarakai, Neville

    2017-02-15

    Babesiosis, a zoonotic parasitic infection transmitted by the Ixodes tick, has become an emerging health problem in humans that is attracting attention worldwide. Most cases of human babesiosis are reported in the United States and Europe. The disease is caused by the protozoa of the genus Babesia, which invade human erythrocytes and lyse them causing a febrile hemolytic anemia. The infection is usually asymptomatic or self-limited in the immunocompetent host, or follows a persistent, relapsing, and/or life threatening course with multi-organ failure, mainly in the splenectomized or immunosuppressed patients. Hematologic manifestations of the disease are common. They can range from mild anemia, to severe pancytopenia, splenic rupture, disseminated intravascular coagulopathy (DIC), or even hemophagocytic lymphohistiocytosis (HLH). A 70 year old immunocompetent female patient living in New York City presented with a persistent fever, night sweats, and fatigue of 5 days duration. Full evaluation showed a febrile hemolytic anemia along with neutropenia and thrombocytopenia. Blood smear revealed intraerythrocytic Babesia, which was confirmed by PCR. Bone marrow biopsy was remarkable for dyserythropoiesis, suggesting possible HLH, supported by other blood workup meeting HLH-2004 trial criteria. Human babesiosis is an increasing healthcare problem in the United States that is being diagnosed more often nowadays. We presented a case of HLH triggered by Babesia microti that was treated successfully. Also, we presented the hematologic manifestations of this disease along with their pathophysiologies.

  7. Manifestation of the shape-memory effect in polyetherurethane cellular plastics, fabric composites, and sandwich structures under microgravity

    Science.gov (United States)

    Babaevskii, P. G.; Kozlov, N. A.; Agapov, I. G.; Reznichenko, G. M.; Churilo, N. V.; Churilo, I. V.

    2016-09-01

    The results of experiments that were performed to test the feasibility of creating sandwich structures (consisting of thin-layer sheaths of polymer composites and a cellular polymer core) with the shapememory effect as models of the transformable components of space structures have been given. The data obtained indicate that samples of sandwich structures under microgravity conditions on board the International Space Station have recovered their shape to almost the same degree as under terrestrial conditions, which makes it possible to recommend them for creating components of transformable space structures on their basis.

  8. Effect of ethnic origin and gender on the clinical manifestations of myasthenia gravis among the Jewish population in Israel.

    Science.gov (United States)

    Asmail, Ali; Kesler, Anat; Drory, Vivian E; Kolb, Hadar; Karni, Arnon

    2017-06-15

    Reports on patients with myasthenia gravis (MG) of different ethnic origins demonstrated differences in weakness distribution and serological results. We studied MG characteristics in a cohort of Ashkenazi (ASH) and non-Ashkenazi (NASH) Jewish origin according to their ethnic origins and gender. The frequency of age of MG onset was distributed in a bi-modal fashion in the female patients and increased gradually over time, with a peak around 70years of age in the male patients. Ocular MG was more frequent in males and ASH patients. Unlike previous reports, our male patients had a higher proportion of positive serum anti-acetyl choline receptor (AChR) than female patients, with no ethnic-based differences in the rates of anti-AChR or anti-muscle specific kinase. Comorbidity with another autoimmune disease was more frequent among female patients with late-onset MG and NASH patients (mainly Israel-born). Male MG patients tended to have more malignant comorbidities than female MG patients. These results demonstrate the effect of ethnicity on clinical aspects of MG within the Jewish population in Israel, and reveal novel effects of gender-associated comorbidities in patients with MG. Copyright © 2017. Published by Elsevier B.V.

  9. Systemic manifestations of hepatitis C infection.

    Science.gov (United States)

    Tang, Lydia; Marcell, Lauren; Kottilil, Shyam

    2016-01-01

    Chronic hepatitis C (HCV) is a common infection affecting 185 million people worldwide. The most common manifestation of chronic HCV is progressive liver fibrosis, cirrhosis, liver failure and hepatocellular carcinoma. However, several systemic manifestations of HCV have been recognized and reported in the literature. The purpose of this review is to assimilate published literature based on evidence to categorize these extrahepatic manifestations with the likelihood of a causal association with HCV. Exciting recent developments have resulted in simple all oral interferon-free highly effective therapy for HCV. However, this treatment is also expensive and less accessible to most affected individuals as treatment recommendations are based on stage of liver fibrosis. Expanding the scope of HCV therapy to those with extrahepatic manifestations beyond what is currently recommended will significantly reduce the morbidity and mortality in this aging population.

  10. Oral manifestations of acute leukaemia

    Directory of Open Access Journals (Sweden)

    Ivanović Mirjana

    2011-01-01

    Full Text Available Acute leukaemia is the most common form of chilhood cancer. The aim of this paper was to underline the importance of oral manifestations in children with acute leukaemia. The disease and its treatment can directly or indirectly affect oral health. Oral manifestations are gingival inflammation and enlargement. Leukaemic cells are capable of infiltrating the gingiva and the deeper periodontal tissues which leads to ulceration and infection of oral tissues. Gingival bleeding is a common sign in patients with leukaemia. Symptoms include local lymphadenopathy, mucous membrane Petechiae and ecchymoses. Cytotoxic drugs have direct effects like mucositis, involving atrophy, desquamation and ulceration of the mucosa, with increasing the risk for local and systemic infections. Leukaemia can directly influence dental care and dental treatment, while oral lesions may have life-threatening consequences. Knowledge and skills among dentists may also not be adequate to treat children with acute leukaemia. It is therefore imperative that all stomatologists be aware of dental problems that occur in leukaemia in order to be able to effectively carry out appropriate measures to mitigate these problems.

  11. Manifestation of external field effect in time-resolved photo-dissociation dynamics of LiF

    Institute of Scientific and Technical Information of China (English)

    Meng Qing-Tian; A.J.C.Varandas

    2013-01-01

    The photo-dissociation dynamics of LiF is investigated with newly constructed accurate ab initio potential energy curves (PECs) using the time-dependent quantum wave packet method.The oscillations and decay of the wave packet on the adiabats as a function of time are given,which can be compared with the femtosecond transition-state (FTS) spectroscopy.The photo-absorption spectra and the kinetic-energy distribution of the dissociation fragments,which can exhibit the vibration-level structure and the dispersion of the wave packet,respectively,are also obtained.The investigation shows a blue shift of the band center for the photo-absorption spectrum and multiple peaks in the kinetic-energy spectrum with increasing laser intensity,which can be attributed to external field effects.By analyzing the oscillations of the wave packet evolving on the upper adiabat,an approximate inversion scheme is devised to roughly deduce its shape.

  12. Origin of radiative recombination and manifestations of localization effects in GaAs/GaNAs core/shell nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S. L.; Filippov, S.; Chen, W. M.; Buyanova, I. A., E-mail: iribu@ifm.liu.se [Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping (Sweden); Ishikawa, Fumitaro [Graduate School of Science and Engineering, Ehime University, 790-8577 Matsuyama (Japan)

    2014-12-22

    Radiative carrier recombination processes in GaAs/GaNAs core/shell nanowires grown by molecular beam epitaxy on a Si substrate are systematically investigated by employing micro-photoluminescence (μ-PL) and μ-PL excitation (μ-PLE) measurements complemented by time-resolved PL spectroscopy. At low temperatures, alloy disorder is found to cause localization of photo-excited carriers leading to predominance of optical transitions from localized excitons (LE). Some of the local fluctuations in N composition are suggested to lead to strongly localized three-dimensional confining potential equivalent to that for quantum dots, based on the observation of sharp and discrete PL lines within the LE contour. The localization effects are found to have minor influence on PL spectra at room temperature due to thermal activation of the localized excitons to extended states. Under these conditions, photo-excited carrier lifetime is found to be governed by non-radiative recombination via surface states which is somewhat suppressed upon N incorporation.

  13. The effect of vitamin D on clinical manifestations and activity of Behçet’s disease

    Directory of Open Access Journals (Sweden)

    Nurşad Aslan

    2017-02-01

    Full Text Available Introduction: Immune mechanisms have been implemented to have a role in the pathogenesis of Behçet’s disease (BD and vitamin D has been shown to have a regulatory role in the immune system function. Aim: To evaluate the vitamin D levels of BD patients and its relationship between clinical findings and disease activity of BD. Material and methods: Sixty-eight patients with BD and 70 age- and sex-matched controls were examined retrospectively. Demographic features, vitamin D levels for both groups and clinical findings, disease activity, drug usage for BD patients were examined from their medical reports. Disease activity was calculated for each patient according to Krause’s BD activity assessment. Results: Mean vitamin D levels of patients and controls were 15.35 ±7.18 ng/ml and 18.44 ±5.79 ng/ml, respectively. Vitamin D levels were significantly lower in BD patients than in controls (p = 0.006. Mean vitamin D levels of active and inactive BD cases were 15.68 ±7.31 ng/ml and 15.08 ±7.17 ng/ml, respectively (p = 0.73. Disease activity of patients using and not using vitamin D was similar (p = 0.51. Conclusions : Significantly lower levels of vitamin D were observed in BD patients. Our results indicate that there is no correlation between BD activity and a vitamin D level. Together with these, vitamin D replacement treatment was found to have no effect on disease activity.

  14. OPHTHALMIC MANIFESTATIONS OF LEUKEMIA

    Directory of Open Access Journals (Sweden)

    E. E. Grishina

    2016-01-01

    Full Text Available Ophthalmic manifestations of leukemia are variable and are predominantly represented by leukemic infiltration of the eye and hemodynamic abnormalities in the retinal vasculature. Leukemic infiltration of the retina should be differentiated from an inflammatory process, such as retinitis, chorioretinitis of viral or fungal origin that are not uncommon in patients with hematological malignancies. Retinal involvement is mainly seen in adult patients with acute myeloid leukemia and is less common in patients with acute lymphoblastic leukemia. Retinopathy is more frequent during relapses of the underlying disease. Also, retinopathy can be the first sign of the disease. Leukemia should be included into the list for differential diagnosis with disorders that can be associated with optical nerve edema and retinal hemorrhages. Fundus abnormalities correlate with peripheral blood parameters. Retinopathy and leukemic optic neuropathy are predictors of unfavorable prognosis. Early diagnostics and timely and adequate treatment may fully eliminate ocular symptoms and improve quality of life in patients with hemoblastoses.

  15. Genitourinary manifestations of tuberculosis.

    Science.gov (United States)

    Wise, Gilbert J; Marella, Venkata K

    2003-02-01

    By the 1980s, the availability of antituberculosis chemotherapy reduced the incidence and prevalence of tuberculosis. Changing patterns of population emigration and the development of large pools of immune-compromised individuals reversed the downward trend of tuberculosis. The incidence of genitourinary tuberculosis has remained constant. The manifestations of GU TB can be variable and cause a variety of clinical patterns that mimic other diseases. Adrenal insufficiency, renal disease, obstructive uropathy, and chronic cystitis are not uncommon with TB. The patient with TB may have genital disease that simulates STD or scrotal tumors. Infertility can be caused by GU tuberculosis. Awareness of environmental factors and patient history should alert the urologist to the wide array of clinical findings in the genitourinary system that can be caused by tuberculosis.

  16. [Pulmonary Manifestations of Vasculitis].

    Science.gov (United States)

    von Vietinghoff, S

    2016-11-01

    The variable symptoms and signs of pulmonary vasculitis are a diagnostic and therapeutic challenge. Vasculitis should be considered in rapidly progressing, severe and unusual manifestations of pulmonary disease. Clinical examination of other organ systems typically affected by vasculitis such as skin and kidney and autoantibody measurements are complementary approaches to manage this situation. Pulmonary involvement is common in small vessel vasculitis including anti-GBM disease (Goodpasture syndrome) and the ANCA-associated vasculitides. Life threatening pulmonary hemorrhage and irreversible damage of other organs, frequently the kidney, are important complications necessitating rapid diagnosis of these conditions.Vasculitides are rare diseases of multiple organs and therapies including biologics are evolving rapidly, requiring cooperation of specialities and with specialized centres to achieve best patient care. All involved physicians should be aware of typical complications of immunosuppressive therapy. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Hepatitis C: extrahepatic manifestations.

    Science.gov (United States)

    Metts, Julius; Carmichael, Lesley; Kokor, Winfred; Scharffenberg, Robert

    2014-12-01

    Chronic hepatitis C virus (HCV) infection is associated with multiple extrahepatic manifestations (EHM) affecting various organs in the body. Approximately 40% to 75% of patients with chronic HCV infection experience at least one clinical EHM during the course of the HCV infection. Mixed cryoglobulinemia (type 2) is the most documented EHM associated with chronic HCV infection. This has been documented in up to 50% of patients. Clinically, it presents as arthralgia, weakness, and cutaneous symptoms. Morphologically, immune complex depositions are identified in small vessels and glomerular capillary walls, leading to leukocytoclastic vasculitis in the skin and membranoproliferative glomerulonephritis in the kidney. In other EHMs of chronic HCV infection not related to cryoglobulinemia, such as Sjögren syndrome, lichen planus, and autoimmune thyroiditis, autoimmune processes resulting in chronic inflammatory infiltrates are thought to be the underlying mechanism.

  18. Warburg effect's manifestation in aggressive pheochromocytomas and paragangliomas: insights from a mouse cell model applied to human tumor tissue.

    Directory of Open Access Journals (Sweden)

    Stephanie M J Fliedner

    Full Text Available A glycolytic profile unifies a group of pheochromocytomas and paragangliomas (PHEOs/PGLs with distinct underlying gene defects, including von Hippel-Lindau (VHL and succinate dehydrogenase B (SDHB mutations. Nevertheless, their tumor aggressiveness is distinct: PHEOs/PGLs metastasize rarely in VHL-, but frequently in SDHB-patients. To date, the molecular mechanisms causing the more aggressive phenotype in SDHB-PHEOs/PGLs remain largely unknown. Recently, however, an excellent model to study aggressive PHEOs (mouse tumor tissue (MTT cells has been developed from mouse PHEO cells (MPC. We employed this model for a proteomics based approach to identify changes characteristic for tumor aggressiveness, which we then explored in a homogeneous set of human SDHB- and VHL-PHEOs/PGLs. The increase of glucose transporter 1 in VHL, and of hexokinase 2 in VHL and SDHB, confirmed their glycolytic profile. In agreement with the cell model and in support of decoupling of glycolysis, the Krebs cycle and oxidative phosphorylation (OXPHOS, SDHB tumors showed increased lactate dehydrogenase levels. In SDHB-PGLs OXPHOS complex activity was increased at complex III and, as expected, decreased at complex II. Moreover, protein and mRNA expression of all tested OXPHOS-related genes were higher in SDHB- than in VHL-derived tumors. Although there was no direct evidence for increased reactive oxygen species production, elevated superoxide dismutase 2 expression may reflect elevated oxidative stress in SDHB-derived PHEOs/PGLs. For the first time, we show that despite dysfunction in complex II and evidence for a glycolytic phenotype, the Warburg effect does not seem to fully apply to SDHB-PHEOs/PGLs with respect to decreased OXPHOS. In addition, we present evidence for increased LDHA and SOD2 expression in SDHB-PHEOs/PGLs, proteins that have been proposed as promising therapeutic targets in other cancers. This study provides new insight into pathogenic mechanisms in

  19. Measuring the effective phonon density of states of a quantum dot in cavity quantum electrodynamics

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg; Nielsen, Per Kær; Kreiner-Møller, Asger

    2013-01-01

    We employ detuning-dependent decay-rate measurements of a quantum dot in a photonic-crystal cavity to study the influence of phonon dephasing in a solid-state quantum-electrodynamics experiment. The experimental data agree with a microscopic non-Markovian model accounting for dephasing from...... longitudinal acoustic phonons, and the analysis explains the difference between nonresonant cavity feeding in different nanocavities. From the comparison between experiment and theory we extract the effective phonon density of states experienced by the quantum dot in the nanocavity. This quantity determines...

  20. Extrahepatic manifestations of chronic viral hepatitis.

    Science.gov (United States)

    Pyrsopoulos, N T; Reddy, K R

    2001-02-01

    Hepatitis B (HBV) and C (HCV) viruses are well-recognized causes for chronic hepatitis, cirrhosis, and even for hepatocellular carcinoma. Apart from liver disease, these viral infections are known to be associated with a spectrum of extrahepatic manifestations. The prevalence of clinically significant extrahepatic manifestations is relatively low, but it can be associated with significant morbidity and even mortality. An awareness and recognition of these manifestations is of paramount importance in facilitating early diagnosis and in offering treatment. However, treatments are not necessarily effective, and patients may continue with disabling extrahepatic manifestations. Hepatitis B virus has been well recognized as causing a variety of manifestations that include skin rash, arthritis, arthralgia, glomerulonephritis, polyarteritis nodosa, and papular acrodermatitis. More recently, infection with hepatitis C virus has elicited considerable interest for its role in a spectrum of extrahepatic manifestations. Among the best-reported are cryoglobulinemia, glomerulonephritis, high titer of autoantibodies, idiopathic thrombocytopenic purpura, lichen planus, Mooren's corneal ulcer, Sjögren's syndrome, porphyria cutanea tarda, and necrotizing cutaneous vasculitis. The precise pathogenesis of these extrahepatic complications has not been determined, although the majority represent the clinical expression of autoimmune phenomena.

  1. Neurological manifestations in Fabry disease

    Institute of Scientific and Technical Information of China (English)

    Joseph Bruno Bidin Brooks; Yara Dadalti Fragoso

    2016-01-01

    Fabry disease (FD) is a rare, progressive, multisystem and highly debilitating disease. FD is an X-linked lysosome storage disorder that results in α-galactosidase A deifciency. The subsequent accumulation of glycosphingolipids is more evident in vascular endothelium and smooth-muscle cells. The resulting effect of the deposition is generalized inlfammation and vasculopathy, which can also affect the central and peripheral nervous system. FD progresses with kidney dysfunction, angiokeratoma of the skin, cardiomyopathy, cerebrovascular events and neurological disorders. In the present review, the neurological manifestations of FD are summarized with emphasis on cerebral vasculopathy, cochlear nerve dysfunction, psychiatric and cognitive symptoms, autonomic dysfunction and peripheral neuropathy. Enzyme replacement therapy is also discussed in the light of its more prominent effects when administered early in life, which make it essential to diagnose FD as soon as possible.

  2. [Pleuropulmonary manifestations of amebiasis].

    Science.gov (United States)

    Mbaye, P S; Koffi, N; Camara, P; Burgel, P R; Hovette, P; Klotz, F

    1998-12-01

    Amibiasis is the third leading cause of death due to parasitic infections in the world. Amibiasis is endemic in the warm regions of the world with deficient hygiene and socio-economic situations. Entamoeba histolytica is the causal agent of invasive amibiasis, unlike Entamoeba dispar which is not a pathogen for humans. Amibian colitis and amibian abscess of the liver are the most frequent intestinal and extra-intestinal manifestations. Pleuropulmonary complications almost always occur in patients with a liver abscess, the intrathoracic contamination via transphrenic dissemination predominating. Respiratory signs are inaugural in 80% of the cases. Pleuropulmonary ambiasis designates the localization of the amibian infestation, but the clinical expression may vary: pneumonia, lung abscess, pleurisy, hepatobronchial fistulization and more infrequently pulmonary embolism. The preferential localization is the right hemithorax related to abscess in the right lobe of the liver. Left lobe abscesses lead to left-sided pleuropulmonary complications with the risk of rupture into the pericardium. Chocolate-colored pus from a pleural or abscess puncture or vomitus strongly suggests the diagnosis, which is confirmed by highly-positive serology. Metronidazole is the treatment of choice, providing cure without sequellae. In Africa, mortality and morbidity due to ambiasis are high. In Abidjan, 92% of cured patients have sequella, and mortality reaches 15%, the consequence of late diagnosis.

  3. Pulmonary manifestation of leptospirosis

    Energy Technology Data Exchange (ETDEWEB)

    Im, Jung Gi; Yeon, Kyung Mo; Han, Man Chung; Kim, Chu Wan; Lee, Jung Sang; Kim, Suhng Gwon; Han, Yong Chol; Chang, Woo Hyun; Chi, Je Geun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1986-02-15

    Authors analysed and present chest X-ray findings of serologically proven leptospirosis from Seoul National University Hospital, either admitted or referred for serological verification, during recent 2 years. Radiological findings were correlated with the lung specimen findings of experimentally induced leptospirosis in guinea pig. The results are as follows: 1. 24 cases (56%) showed positive X-ray findings. 2. Predominant radiological patterns of involved lung were tiny dot, small nodule, rosette density in 11 cases, massive confluent consolidation in 4 cases, and diffuse ill-defined velly increased density in 9 cases. 3. Distribution of pulmonary lesions were bilateral (100%), non-lobar, non-segmental (95%), and there were conspicuous tendency of peripheral lung predominance. 4. Extrapulmonary manifestation, such as pleural effusion or cardiomegaly was rate. 5. Pulmonary lesions resolved completely usually 5 to 10 days after their appearance. 6. From the gross and microscopic findings of serially sacrificed guinea pig's lung and a case of autopsy, authors concluded that fine dot-like density in chest X-ray was due to paleolithic hemorrhage in intraalveolar space at initial stage, growing up to ressette density or confluent consolidation as the pathetic extends to surrounding lung forming purpura and coalescent hemorrhage.

  4. Gastrointestinal manifestations of endocrine disease

    Institute of Scientific and Technical Information of China (English)

    Christina Maser; Arnbjorn Toset; Sanziana Roman

    2006-01-01

    The hormonal interactions among the systems throughout the body are not fully understood; many vague clinical symptoms may in fact be manifestations of underlying endocrine diseases. The aim of the following review is to discuss gastrointestinal manifestations of surgically correctable endocrine diseases, focusing on abnormalities of thyroid function, cancer and finally autoimmune diseases. We also review manifestations of pancreatic endocrine tumors, and multiple endocrine neoplasia.

  5. [Extrahepatic manifestations in hepatitis C].

    Science.gov (United States)

    Risum, Malene

    2011-05-09

    Hepatitis C does not only affect the liver, but also manifests outside the liver. The skin, kidneys and nervous system are often involved due to mixed cryoglobulinaemia. Porphyria cutanea tarda, lymphoma and thyroid diseases among others can also attend a chronic infection, but the exact pathogenesis behind these manifestations is not clearly mapped. Antiviral treatment is reported to induce sustained virological response in more than half of the treated patients with a variable clinical response in the extrahepatic manifestations.

  6. Extrahepatic manifestations of hepatitis C.

    Science.gov (United States)

    Palekar, Nicole A; Harrison, Stephen A

    2005-10-01

    Hepatitis C affects approximately 170 million people worldwide. Extrahepatic manifestations of chronic hepatitis C infection are clinically evident in nearly 40% of patients. Much research has been done over the last decade to better understand their incidence, clinical presentation, mechanism of disease, and the role of antiviral therapy in their treatment. Of the commonly reported manifestations, cryoglobulinemia, membranoproliferative glomerulonephritis, and porphyria cutanea tarda remain the best understood manifestations. More recently, the association of insulin resistance and diabetes mellitus with chronic hepatitis C has been demonstrated. This paper serves to review the growing body of literature detailing the extrahepatic manifestations of chronic hepatitis C.

  7. Ocular manifestations of mitochondrial disease

    Directory of Open Access Journals (Sweden)

    S. D. Mathebula

    2012-12-01

    Full Text Available Mitochondrial disease caused by mutations in mitochondrial DNA is recognized as one of the most common causes of inherited neurological disease. Neuro-ophthalmic manifestations are a common feature of mitochondrial disease.  Optic atrophy causing central visual loss is the dominant feature of mitochondrial DNA diseases. Nystagmus is also encountered in mitochondrial disease.Although optometrists are not involved with the management of mitochondrial disease, they are likely to see more patients with this disease. Oph-thalmic examination forms part of the clinical assessment of mitochondrial disease. Mitochondrial disease should be suspected in any patient with unexplained optic neuropathy, ophthalmoplegia, pigmentary retinopathy or retrochiasmal visual loss. Despite considerable advances in the under-standing of mitochondrial genetics and the patho-genesis of mtDNA diseases, no effective treatment options are currently available for patients withmitochondrial dysfunction. (S Afr Optom 201271(1 46-50

  8. Respiratory manifestations in amyloidosis

    Institute of Scientific and Technical Information of China (English)

    XU Ling; CAI Bai-qiang; ZHONG Xu; ZHU Yuan-jue

    2005-01-01

    Background Amyloidosis is a collection of diseases in which different proteins are deposited. Amyloid deposits occur in systemic and organ-limited forms. In both systemic and localized forms of the disease, lung can be involved. The aim of this study was to explore the different respiratory manifestations of amyloidosis. Methods Chest radiology, clinical presentations, bronchoscopic/laryngoscopic findings and lung function data of 59 patients with amyloidosis involving respiratory tract collected during January 1986 to March 2005, were analysed.Results Of the 16 cases with localized respiratory tract amyloidosis, 8 had the lesions in the trachea and the bronchi, 2 in the larynx and the trachea, 5 in the larynx and/or the pharynx, and 1 in the lung parenchyma. Of 43 systemic amyloidosis with respiratory tract involvement, 3 had the lesions in bronchi, 13 in lung parenchyma, 33 in pleura, 8 in mediastina, 1 in nose and 1 in pharynx. Chest X-rays were normal in most cases of tracheobronchial amyloidosis. CT, unlike chest X-rays, showed irregular luminal narrowing, airway wall thickening with calcifications and soft tissue shadows in airway lumen. Localized lung parenchymal amyloidosis presented as multiple nodules. Multiple nodular opacities, patch shadows and reticular opacities were the main radiological findings in systemic amyloidosis with lung parenchymal involvement. In pleural amyloidosis, pleural effusions and pleural thickening were detected. Mediastinal and/or hilar adenopathy were also a form of lung involvement in systemic amyloidosis. The major bronchoscopic findings of tracheobronchial amyloidosis were narrowing of airway lumen, while nodular, 'tumour like' or 'bubble like' masses, with missing or vague cartilaginous rings, were detected in about half of the patients.Conclusions Localized respiratory tract amyloidosis mostly affects the trachea and the bronchi. Chest X-rays are not sensitive to detect these lesions. Systemic amyloidosis often involves

  9. Hyaline fibromatosis syndrome: cutaneous manifestations*

    Science.gov (United States)

    Marques, Silvio Alencar; Stolf, Hamilton Ometto; Polizel, Juliana Ocanha; Munhoz, Tânia; Brandão, Marcela Calixto; Marques, Mariangela Esther Alencar

    2016-01-01

    Hyaline fibromatosis syndrome is the current name for clinical manifestations of diseases previously known as “infantile systemic hyalinosis” and “juvenile hyaline fibromatosis”. The authors report representative clinical cases of each one of the above subtypes with emphasis on cutaneous manifestations and difficulties for early diagnosis in this syndrome, essentially of multidisciplinary approach. PMID:27192526

  10. Cerebrovascular manifestations following scorpion sting

    OpenAIRE

    Nataraja P; Naveen Prasad SV; Obulareddy G; Anil Ch; Naveen T; Vengamma B

    2016-01-01

    Scorpion sting is a common clinical problem in Rayalaseema area of Andhra Pradesh State in India. Clilnical presentation of scorpion envenomation can range from mild local pain to systemic manifestations involving almost all systems. Cerebrovascular manifestations of scorpion sting have been sparsely documented. We report two cases who presented with ischaemic stroke and haemorrhagic stroke following scorpion sting.

  11. Neuropsychiatric manifestations of scrub typhus

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    Sanjay K Mahajan

    2017-01-01

    Full Text Available Scrub typhus is caused by Orientia tsutsugamushi characterized by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system. It was thought to have been eradicated from India. Recently it is being reported from many areas of India. The clinical picture and severity of the symptoms varies widely. The neurological manifestations of scrub typhus are not uncommon but are diverse. Meningoencephalitis is classical manifestation of scrub typhus but cerebellitis, cranial nerve palsies, plexopathy, transverse myelitis, neuroleptic malignant syndrome and Guillan-Barré syndrome are other manifestations reported in literature. The availability of literature on the neurological manifestations of scrub typhus is limited to case reports mainly. This article reviews various neurological manifestations of scrub typhus reported in literature.

  12. Ocular manifestations in systemic lupus erythematosus.

    Science.gov (United States)

    Silpa-archa, Sukhum; Lee, Joan J; Foster, C Stephen

    2016-01-01

    Systemic lupus erythematosus (SLE) can involve many parts of the eye, including the eyelid, ocular adnexa, sclera, cornea, uvea, retina and optic nerve. Ocular manifestations of SLE are common and may lead to permanent blindness from the underlying disease or therapeutic side effects. Keratoconjunctivitis sicca is the most common manifestation. However, vision loss may result from involvement of the retina, choroid and optic nerve. Ocular symptoms are correlated to systemic disease activity and can present as an initial manifestation of SLE. The established treatment includes prompt systemic corticosteroids, steroid-sparing immunosuppressive drugs and biological agents. Local ocular therapies are options with promising efficacy. The early recognition of disease and treatment provides reduction of visual morbidity and mortality.

  13. The effect of highly active antiretroviral therapy on the prevalence of oral manifestation in human immunodeficiency virus-infected patients in Karnataka, India

    Science.gov (United States)

    Patil, Neelkant; Chaurasia, Vishwajit Rampratap; Babaji, Prashant; Ramesh, Dnsv; Jhamb, Kshitij; Sharma, Akanksha Manmohan

    2015-01-01

    Objectives: Acquired Immunodeficiency Syndrome (AIDS) is a highly lethal, progressively epidemic viral infection characterized by profound impairment of the immune system. Oral manifestations are common in Human Immunodeficiency Virus (HIV) infected AIDS patients, and are usually the first indicator of symptom and disease progression. The main objective of the current study was to compare the prevalence of oral manifestations in HIV patients on Highly Active Antiretroviral Therapy (HAART) with those, not on HAART therapies. Materials and Methods: A cross sectional study was conducted among 100 patients diagnosed as human immune virus sero-positive. These patients were divided equally into two groups (50 each); Group I patients on HAART and Group II patients who were not on HAART. Information regarding age, sex and cluster of differentiation 4 cell count was obtained from the medical records. Oral examination was done, and findings were recorded by using internationally accepted presumptive clinical criteria. Statistical analysis was performed using Chi-square statistical test. Results: The presence of oral manifestations was significantly decreased in subjects on HAART (32%) compared to those who are not on HAART (56%). The most common oral lesions detected in patients on HAART were increased oral hyper-pigmentation (14%), recurrent aphthous stomatitis (8%), non-specific ulcerations (4%), pseudo-membranous candidiasis (2%), periodontitis (2%) and xerostomia (2%), whereas in non HAART oral hyperpigmentation (10%), pseudo-membranous candidiasis (8%), angular cheilitis (4%), and erythematous candidiasis (4%) and Periodontitis (14%) were more prevalent. Conclusion: The number and severity of oral manifestation decreased, and even there was a change in the type of oral manifestations on HAART, which may be because of the improvement in immunity gained by the therapy. PMID:25713484

  14. Cutaneous Manifestations of Crohn Disease.

    Science.gov (United States)

    Hagen, Joshua W; Swoger, Jason M; Grandinetti, Lisa M

    2015-07-01

    Awareness of the extraintestinal manifestations of Crohn disease is increasing in dermatology and gastroenterology, with enhanced identification of entities that range from granulomatous diseases recapitulating the underlying inflammatory bowel disease to reactive conditions and associated dermatoses. In this review, the underlying etiopathology of Crohn disease is discussed, and how this mirrors certain skin manifestations that present in a subset of patients is explored. The array of extraintestinal manifestations that do not share a similar pathology, but which are often seen in association with inflammatory bowel disease, is also discussed. Treatment and pathogenetic mechanisms, where available, are discussed.

  15. Ocular manifestations of feline herpesvirus.

    Science.gov (United States)

    Andrew, S E

    2001-03-01

    Feline herpesvirus-1 (FHV-1) infection is ubiquitous in the domestic cat population worldwide. The most common clinical ocular manifestations of infection with FHV-1 are conjunctivitis and keratitis. This paper reviews the pathogenesis of feline herpesvirus-1 and discusses the various clinical ocular manifestations, diagnostic techniques and treatment of FHV-1-induced diseases. Ocular manifestations include: conjunctivitis, keratitis, stromal keratitis, keratoconjunctivitis sicca, ophthalmia neonatorium, symblepharon, corneal sequestrum, eosinophilic keratitis and anterior uveitis. Diagnostic techniques discussed include: virus isolation, fluorescent antibody testing, serum neutralising titers, ELISA and polymerase chain reaction. Various therapies are also discussed.

  16. Rheumatic manifestations of pituitary tumors.

    Science.gov (United States)

    Stavrou, S; Kleinberg, D L

    2001-10-01

    Pituitary tumors may cause rheumatologic problems as a result of under production or overproduction of one pituitary hormone. Excessive growth hormone causes destruction of cartilage by a direct action. Facial and acral changes and arthralgias may be some of the first symptoms of acromegaly. The arthritis associated with acromegaly is often devastating. Carpal tunnel syndrome is very common in patients with acromegaly. Adrenocorticotropin (ACTH) has indirect effects via the action of glucocorticoid on bones, muscles, and the immune system. Proximal muscle weakness is a characteristic feature of Cushing's syndrome. Patients with Cushing's syndrome commonly have osteopenia and osteoporosis that lead to an increase in bone fractures. Avascular necrosis is associated with exogenous steroid administration. The effects of too much glucocorticoid or too rapid withdrawal can be severe. Gonadotropins act via the gonadal steroids and protect bone mass from loss. Prolactin is less involved in rheumatologic disease; the data for which are limited in humans. Pituitary tumors can have manifestations similar to rheumatologic disorders and should be included in the differential diagnosis of these diseases.

  17. Renal (Kidney) Manifestations in TSC

    Science.gov (United States)

    ... International TSC Research Conference Text Size Get Involved RENAL (KIDNEY) MANIFESTATIONS IN TSC Download a PDF of ... sclerosis complex (TSC) will develop some form of renal (kidney) disease during their lifetime. There are three ...

  18. Memory effects on epidemic evolution: The susceptible-infected-recovered epidemic model

    Science.gov (United States)

    Saeedian, M.; Khalighi, M.; Azimi-Tafreshi, N.; Jafari, G. R.; Ausloos, M.

    2017-02-01

    Memory has a great impact on the evolution of every process related to human societies. Among them, the evolution of an epidemic is directly related to the individuals' experiences. Indeed, any real epidemic process is clearly sustained by a non-Markovian dynamics: memory effects play an essential role in the spreading of diseases. Including memory effects in the susceptible-infected-recovered (SIR) epidemic model seems very appropriate for such an investigation. Thus, the memory prone SIR model dynamics is investigated using fractional derivatives. The decay of long-range memory, taken as a power-law function, is directly controlled by the order of the fractional derivatives in the corresponding nonlinear fractional differential evolution equations. Here we assume "fully mixed" approximation and show that the epidemic threshold is shifted to higher values than those for the memoryless system, depending on this memory "length" decay exponent. We also consider the SIR model on structured networks and study the effect of topology on threshold points in a non-Markovian dynamics. Furthermore, the lack of access to the precise information about the initial conditions or the past events plays a very relevant role in the correct estimation or prediction of the epidemic evolution. Such a "constraint" is analyzed and discussed.

  19. Nail manifestations in pemphigus vulgaris

    Directory of Open Access Journals (Sweden)

    Cahali Juliana Burihan

    2002-01-01

    Full Text Available Nail involvement in pemphigus vulgaris is rare. We describe 5 patients with pemphigus vulgaris presenting nail involvement. In this disease, nail manifestations present, by order of frequency, as chronic paronychia, onychomadesis, onycholysis, Beau's lines and trachyonychia. All our 5 cases presented with paronychia, and 1 of them also had Beau's lines. Treatment with prednisone and/or cyclophosphamide controlled mucocutaneous and nail manifestations in all cases.

  20. Manifestations of advanced civilizations

    Science.gov (United States)

    Bracewell, R. N.

    A list of possible modes of detecting advanced civilizations elsewhere in the universe is provided, including EM Alfven, and gravity waves, matter transfer, and exotica such as tachyons, black hole tunneling, and telepathy. Further study is indicated for low frequency radio wave propagation, which may travel along magnetic fields to reach the earth while laser beams are not favored because of the power needed for transmitting quanta instead of waves. IR, X ray, and UV astronomy are noted to be suitable for detecting signals in those ranges, while Alfven wave communication will be best observed by probes outside the orbit of Jupiter, where local anomalies have less effect. Particle propagation communication is viewed as unlikely, except as a trace of an extinct civilization, but panspermia, which involves interstellar spreading of seeds and/or spores, receives serious attention, as does laser probe or pellet propulsion.

  1. Cutaneous manifestations of human toxocariasis.

    Science.gov (United States)

    Gavignet, Béatrice; Piarroux, Renaud; Aubin, François; Millon, Laurence; Humbert, Philippe

    2008-12-01

    Human toxocariasis is a parasitic disease characterized by the presence of larvae of the genus Toxocara in human tissues. T canis and T cati, the adult roundworms of which are found in dog and cat intestines, respectively, are the most common causative agents of the disease. Toxocaral larvae usually cause two severe syndromes: visceral larva migrans and ocular larva migrans, depending on the location of the larvae. Two other syndromes, covert toxocariasis and common toxocariasis, which are less typical and not as severe, have also been described. During the last two decades, cutaneous manifestations such as chronic urticaria, chronic pruritus, and miscellaneous eczema, in patients with Toxocara antibodies, have been studied by different authors. In some cases, these cutaneous manifestations are the only signs indicating the presence of the disease, and they are cured after antihelmintic treatment when there is good patient compliance. In this review, we focus on these particular skin manifestations regarding their clinical description, diagnosis, and treatment.

  2. [Cardiovascular manifestations of human toxocariasis].

    Science.gov (United States)

    Bolívar-Mejía, Adrián; Rodríguez-Morales, Alfonso J; Paniz-Mondolfi, Alberto E; Delgado, Olinda

    2013-01-01

    Toxocariasis is a parasitic infection produced by helminths that cannot reach their adult stage in humans. For their etiological species (Toxocara canis and Toxocara cati), man is a paratenic host. Infection by such helminths can produce a variety of clinical manifestations, such as: visceral larvae migrans syndrome, ocular larvae migrans syndrome and covert toxocariasis. In the visceral larvae migrans syndrome, the organs that are mainly involved include liver, lungs, skin, nervous system, muscles, kidneys and the heart. Regarding the latter, the importance of cardiovascular manifestations in toxocariasis, as well as its clinical relevance, has increasingly begun to be recognized. The current article is based on a systematic information search, focused mainly on the clinical and pathological aspects of cardiovascular manifestations in toxocariasis, including its pathophysiology, laboratory findings, diagnosis and therapeutical options, with the objective of highlighting its importance as a zoonosis and its relevance to the fields of cardiovascular medicine in adults and children.

  3. RHEUMATIC MANIFESTATIONS IN VIRAL HEPATITIS

    Directory of Open Access Journals (Sweden)

    L P Anan'eva

    2008-01-01

    Full Text Available Autoimmune reactions are of primary importance in the development of extrahepatic manifestations of viral hepatitis, among which there are rheumatic symptoms and syndromes. The incidence of clinically significant extrahepatic manifestations is shown to be relatively low, but they may be in the foreground in the clinical picture of the disease and are noted for severity. It is concluded that due to the high prevalence of hepatitis and the systemic pattern of their chronic forms, patients with extrahepatic manifestations of viral hepatitis may be encountered in the practice of a therapist and a rheumatologist. The onset of the infection caused by hepatitis viruses may be accompanied by articular lesion therefore the rheumatologist may be the first physician such a patient may resort to.

  4. RHEUMATIC MANIFESTATIONS IN VIRAL HEPATITIS

    Directory of Open Access Journals (Sweden)

    L P Anan'eva

    2008-12-01

    Full Text Available Autoimmune reactions are of primary importance in the development of extrahepatic manifestations of viral hepatitis, among which there are rheumatic symptoms and syndromes. The incidence of clinically significant extrahepatic manifestations is shown to be relatively low, but they may be in the foreground in the clinical picture of the disease and are noted for severity. It is concluded that due to the high prevalence of hepatitis and the systemic pattern of their chronic forms, patients with extrahepatic manifestations of viral hepatitis may be encountered in the practice of a therapist and a rheumatologist. The onset of the infection caused by hepatitis viruses may be accompanied by articular lesion therefore the rheumatologist may be the first physician such a patient may resort to.

  5. Cutaneous manifestations of viral hepatitis.

    Science.gov (United States)

    Akhter, Ahmed; Said, Adnan

    2015-02-01

    There are several extrahepatic cutaneous manifestations associated with hepatitis B and hepatitis C virus infection. Serum sickness and polyarteritis nodosa are predominantly associated with hepatitis B infection, whereas mixed cryoglobulinemia associated vasculitis and porphyria cutanea tarda are more frequently seen in hepatitis C infection. The clinico-pathogenic associations of these skin conditions are not completely defined but appear to involve activation of the host immune system including the complement system. Management of the aforementioned cutaneous manifestations of viral hepatitis is often similar to that done in cases without viral hepatitis, with control of immune activation being a key strategy. In cases associated with hepatitis B and C, control of viral replication with specific antiviral therapy is also important and associated with improvement in most of the associated clinical manifestations.

  6. Efecto de los tratamientos antirretrovirales en las manifestaciones orales de los pacientes VIH+ Effects of antiretrovial treatments on oral manifestations in HIV+patients

    Directory of Open Access Journals (Sweden)

    E. Jané-Salas

    2006-12-01

    Full Text Available El presente trabajo es un estudio para valorar el efecto de los tratamientos antirretrovirales en pacientes seropositivos al VIH, visitados en el dispensario de enfermedades infecciosas del Hospital Vall D´Hebron de Barcelona. Se visitaron 90 pacientes, 51 varones (56,7% y 39 mujeres (43,3%, siendo la edad media de los pacientes de 36,2 años con una desviación de ±17,8 años y una moda de 35 años. Las visitas fueron realizadas desde enero a diciembre del año 1999. Estos pacientes recibían tratamiento antirretroviral de uno o más fármacos y algunos de ellos (32,2% estaban sometidos a tratamiento antirretroviral de alta actividad (TAAA. Asimismo, en estos pacientes se valoró el recuento de CD4 y carga viral de forma bimodal, al inicio del proceso y en el momento de la visita. La exploración de la cavidad oral se realizó en este momento, buscando las lesiones asociadas al Sida según la clasificación de Pindborg y cols., de 1989. La patología más prevalente encontrada en este estudio fue la sensación de boca seca o xerostomía en un 47,8%, seguida por orden de frecuencia de policaries (34,4% y candidiasis eritematosa (31,1%. Otras manifestaciones orales son muy poco frecuentes, en comparación con los resultados de otros autores en la etapa previa a la utilización de los inhibidores de la proteasa (IP. Así, por ejemplo, se observó un solo caso de leucoplasia vellosa, tan característica antes del año 1996.We evaluate the effects of antiretroviral treatments in HIV seropositive patients, who were seen in the Clinic for Infectious Diseases in the Vall D´Hebron Hospital, Barcelona. 90 patients were seen, 51 males (56.7% and 39 females (43.3%, the mean age of the patients was 36.2 years with a deviation of ±17.8, and a mode of 35 years. The visits were carried out between January and December 1999. These patients were receiving antiretroviral treatment with one or more drugs and some of them (32.2% were subjected to high activity

  7. Effect of the diet and growing conditions on the manifestations of cannibalism in the eastern freshwater shrimp (Macrobrachium nipponense De Haan, 1849

    Directory of Open Access Journals (Sweden)

    P. Shekk

    2017-06-01

    Full Text Available Purpose. To study the effect of diet and water flow composition on the manifestations of cannibalism of shrimp Macrobrachium nipponense during rearing under controlled conditions. Methodology. The material for the work was shrimp fry with a length 2.0-3.5 cm and weight 1.5-3.0 g, caught in autumn 2016 in ponds of the lower reaches of the Dniester river. The shrimp were kept in tanks of the recirculation system with a volume of 0.3 m3. The temperature regime, light (period and intensity, and other environmental parameters were maintained in accordance with the specified parameters. Weighing was carried out on an AXISAD-50 electronic balance with an accuracy of 0.001 g. The length was measured with a ruler or with a caliper. In chronic experiments, two groups of shrimps were kept at the stocking density of 3 ind./L, temperature of 26-29°C and other equal conditions in tanks of a recirculating system. The diet of the first group consisted of animal food (bloodworm, fish, squid, snail, tubule, artemia, the second group was fed by plant feeds (cereals, vegetables, spinach, nuts, alfalfa, rice, chickpeas. Maturation of females in the second group was not observed. At the same time, cases of aggressive behavior were rare, and cannibalism was not observed, which ensured 100% survival. In the second series of experiments, shrimp were kept in fattening tanks at stocking density of 2 ind./L and a ratio ♂♂: ♀♀ - 1: 4. The diet of shrimp consisted of animal and plant feeds (1: 1. During the 30 days of the experiment, the water temperature was maintained at 26.0 ± 0.5 °C, the photoperiod was 12 hours light, 12 hours dark. Findings. The shrimp, which received animal food, grew faster. 20% of the females formed eggs. At the same time, their aggressiveness was high, which led to the loss due to injuries and cannibalism of 40% of the individuals. The shrimp, which received vegetable food, grew slower. Their final weight and size were significantly

  8. Quantum manifestations of Nekhoroshev stability

    Energy Technology Data Exchange (ETDEWEB)

    Fontanari, Daniele, E-mail: fontanari@purple.univ-littoral.fr [Département de physique, Université du Littoral – Côte d' Opale, 59140 Dunkerque (France); Fassò, Francesco, E-mail: fasso@math.unipd.it [Università di Padova, Dipartimento di Matematica, Via Trieste 63, Padova 35121 (Italy); Sadovskií, Dmitrií A., E-mail: sadovski@univ-littoral.fr [Département de physique, Université du Littoral – Côte d' Opale, 59140 Dunkerque (France)

    2016-09-16

    We uncover quantum manifestations of classical Nekhoroshev theory of resonant dynamics using a simple quantum system of two coupled angular momenta with conserved equal magnitudes which corresponds to a perturbed classical integrable anisochronous Hamiltonian system. - Highlights: • Basic quantum manifestations of classical Nekhoroshev theory are studied. • A simple anisochronous convex system with two degrees of freedom is proposed. • Zones are uncovered in the joint expectation value spectrum of quantized actions. • The width of the zones is given by the Nekhoroshev resonant normal forms.

  9. Cutaneous manifestations in celiac disease

    Institute of Scientific and Technical Information of China (English)

    L Abenavoli; G Addolorato; I Proietti; L Leggio; A Ferrulli; L Vonghia; R Capizzi; M Rotoli; PL Amerio; G Gasbarrini

    2006-01-01

    Celiac disease (CD) is an autoimmune gluten-dependent enteropathy characterized by atrophy of intestinal villi that improves after gluten-free diet (GFD). CD is often associated with extra-intestinal manifestations;among them, several skin diseases are described in CD patients. The present review reports all CD-associated skin manifestations described in the literature and tries to analyze the possible mechanisms involved in this association. The opportunity to evaluate the possible presence of CD in patients affected by skin disorders is discussed.

  10. Dermatologic Manifestations of Systemic Diseases.

    Science.gov (United States)

    Valdez, Maryn Anne; Isamah, Nwamaka; Northway, Rebecca M

    2015-12-01

    Dermatologic complaints are encountered frequently by the primary care provider. Patients often are required as well as want to see their primary care provider before referral to a specialist. Therefore, primary care providers must be skilled in a variety of topics including dermatology. Certain dermatologic manifestations are associated with, or indicative of, systemic diseases. Primary care providers must be knowledgeable in diagnosis, evaluation, and treatment of dermatologic conditions, as well as when to appropriately refer. This article reviews common dermatologic manifestations of systemic diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. [Pulmonary, pleural and pericardial manifestations of rickettsiosis].

    Science.gov (United States)

    Piéron, R; Lesobre, B; Mafart, Y; Meyniel, D; Coppin, M

    1976-01-01

    The authors report four observations of rickettsioses with R. conori (3 cases) or R. mooseri (1 case) with pericardial, pleural or pulmonary manifestations (2 cases). On this occasion, they recall that diagnosis of rickettsiosis can only be made on precise conditions: compatible clinical syndrome, significantly increasing then decreasing antibodies level, negative bacteriological and viral investigations and effectiveness of particular antibiotics. They also recall the main characteristics of pericardites, pleurisies, and pneumopathies produced by rickettsiae, probably more frequently than previously thought.

  12. The effects of location, experiences with the civil disturbances and religion on death anxiety and manifest anxiety in a sample of Northern Ireland university students.

    Science.gov (United States)

    Mercer, G W; Bunting, B; Snook, S

    1979-06-01

    A total of 315 Northern Ireland university students were compared to 302 Republic of Ireland university students in terms of death anxiety, manifest anxiety, and perception of dangerousness of aspects of their environment and attitudes toward the civil disturbances in Northern Ireland. Also using these variables in the Northern Ireland sample, Protestants were compared to Catholics, those having had experiences with the disturbances were compared to those not having had such experiences, and those living in nominally dangerous areas of Belfast were compared to those living in nominally safer areas of Belfast. Students living in Northern Ireland had higher death anxiety and stronger fears than students living in the Republic. Those having had experiences with the civil violence had higher manifest anxiety and stronger fears than those not having has such experiences. Persons living in safe environments thought the disturbances to be more serious than those living in more dangerous environments, a result which is discussed in terms of the media and cognitive dissonance. Finally, an argument is made that the influence of religious denomination is an overemphasized variable in the understanding of the civil disturbances.

  13. Cardiac Manifestation in Dengue Fever.

    Science.gov (United States)

    Arora, Mohit; Patil, Rekha S

    2016-07-01

    To study the cardiac manifestations of the dengue fever. This one year descriptive study was undertaken at KLES Dr. Prabhakar Kore Hospital and Medical Research Centre, Belgaum under the Department of Medicine. A total of 120 patients with either dengue IgM or IgM and IgG were studied. The assessment of cardiac manifestations was done based on electrocardiogram, 2D echocardiography and cardiac enzymes. Of the 120 patients, 85 (70.83%) were males and the male to female ratio was 2.4:1. The mean age of the patients was 33.02 ± 12.71 years. The commonest clinical presentation was myalgia (97.5%) followed by fever (92.5%). On clinical examination 33.33% of the patients had petecheia and only 9 patients having active bleeding manifestation at the time of presentation. A raised CK-MB and Troponin I was observed in 33.3% and 26.7% patients ECG findings revealed normal rhythm among 95% with 15.8% of them having an abnormal heart rate. Rhythm disturbance was noted in 5% of the patients with AV block being the most common (66.67%). Cardiac manifestation in the form of myocarditis was observed in 37.50% of the patients with a positive correlation with the severity of the dengue fever defined as by W.H.O. criteria. Patients with dengue fever are at high risk of developing myocarditis and rhythm disturbance and therefore require a close cardiac monitoring.

  14. Neurological Manifestations of Takayasu Arteritis

    Institute of Scientific and Technical Information of China (English)

    Li-xin Zhou; Jun Ni; Shan Gao; Bin Peng; Li-ying Cui

    2011-01-01

    Objective To investigate the clinical neurological manifestations of Takayasu arteritis (TA).Methods A retrospective study was conducted with 63 consecutive TA cases admitted to Peking Union Medical College Hospital from January 2009 to May 2010.All the patients fulfilled the diagnostic criteria of TA by the American College of Rheumatology.Among the 63 TA patients,27 with neurological manifestations were included in the present study.All the patients were evaluated using standardized neurological examination,sonography,computed tomography (CT) angiography,and cerebral CT or magnetic resonance imaging.Results Dizziness and visual disturbance were the most common symptoms,which occurred in 20 (74.1%) and 16 (59.3%) patients respectively.Another common symptom was headache,observed in 15 (55.6%) patients.Six (22.2%) patients had suffered from ischemic stroke; 7 (25.9%) patients had epileptic seizures.Two (7.4%) patients were diagnosed as reversible posterior encephalopathy syndrome (RPES) based on typical clinical and imaging manifestations.Conclusions Neurological manifestations are common symptoms in TA patients in the chronic phase,including dizziness,visual disturbance,headache,ischemic stroke,seizures,and some unusual ones such as RPES.We suggested RPES be included into the differential diagnosis of acute neurological changes in TA.

  15. Mucocutaneous manifestations of Cowden's syndrome

    Directory of Open Access Journals (Sweden)

    Kundoor Vinay Kumar Reddy

    2016-01-01

    Full Text Available Cowden's syndrome is an autosomal dominant genodermatosis with variable orofacial and systemic manifestations. Here we present one such classical case of Cowden's syndrome in a 45-year-old female patient with features such as multiple cutaneous papillomatosis, oral fibromas, and fibromas involving multiple organs such as gastrointestinal tract (multiple polyps, thyroid disorders, and breast cancer.

  16. Antiphospholipid antibody: laboratory, pathogenesis and clinical manifestations

    Directory of Open Access Journals (Sweden)

    T. Ziglioli

    2011-06-01

    Full Text Available Antiphospholipid antibodies (aPL represent a heterogeneous group of antibodies that recognize various antigenic targets including beta2 glycoprotein I (β2GPI, prothrombin (PT, activated protein C, tissue plasminogen activator, plasmin and annexin A2. The most commonly used tests to detect aPL are: lupus anticoagulant (LAC, a functional coagulation assay, anticardiolipin antibody (aCL and anti-β2GPI antibody (anti-β2GPI, which are enzyme-linked immunoassay (ELISA. Clinically aPL are associated with thrombosis and/or with pregnancy morbidity. Apparently aPL alone are unable to induce thrombotic manifestations, but they increase the risk of vascular events that can occur in the presence of another thrombophilic condition; on the other hand obstetrical manifestations were shown to be associated not only to thrombosis but mainly to a direct antibody effect on the trophoblast.

  17. Hepatic manifestations of non-steroidal inflammatory bowel disease therapy

    Institute of Scientific and Technical Information of China (English)

    Robert; Hirten; Keith; Sultan; Ashby; Thomas; David; E; Bernstein

    2015-01-01

    Inflammatory bowel disease(IBD) is composed of Crohn’s disease and ulcerative colitis and is manifested by both bowel-related and extraintestinal manifestations. Recently the number of therapeutic options available to treat IBD has dramatically increased, with each new medication having its own mechanism of action and side effect profile. A complete understanding of the hepatotoxicity of these medications is important in order to distinguish these complications from the hepatic manifestations of IBD. This review seeks to evaluate the hepatobiliary complications of non-steroid based IBD medications and aide providers in the recognition and management of these side-effects.

  18. 40 CFR 262.21 - Manifest tracking numbers, manifest printing, and obtaining manifests.

    Science.gov (United States)

    2010-07-01

    ... AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE The... paragraph (c) of this section, EPA will provide the registrant an electronic file of the manifest... for Transporters” on Copy 5; and (C) The “Instructions for Treatment, Storage, and Disposal...

  19. NEUROLOGIC MANIFESTATION OF ORGANIC ACADEMIA

    Directory of Open Access Journals (Sweden)

    Seyyed Hassan TONEKABONI

    2012-03-01

    Full Text Available Inborn errors of organic acid metabolism are relatively recently recognized diseases with a wide spectrum of clinical signs and symptoms: ranging from asymptomatic, normal appearing children to death during first few days of life.In my presentation I will try to explain some of the most common clinical presentation of these disorder with stress on neurologic findings. Organic acidemia usually have three clinical manifestations Severe neonatal form, Intermittent late-onset form and chronic progressive form. Recurrent coma, The main feature of these disorders is due to accumulation of toxic metabolites in Central Nervous system with direct effect on the function, while chronic accumulation of these materials may interfere with CNS development or cerebral metabolism leading to developmental delay.Severe neonatal formsFollowing a symptom free interval of a few days from birth, poor sucking and difficult feeding appears in the newborn, followed by unexplained and progressive coma. Seizures may appear during the course of the disease and EEG may show a burst-suppression pattern. During this stage most infants have axial hypotonia with peripheral dystonia, choreoathetosis, episodic opisthotonus and some repetitive bicycling and boxing movements.Associated biochemical abnormalities including metabolic acidosis, ketonuria and hyperammonemia also is usually present. The overall short-term prognosis with recent advances in medical care is improving. But later in life acute intercurrent episodes triggered by a stress often occur, which can be occasionally fatal.bulging fontanelle and cerebral edema may mimic CNS infection in these babies.Intermittent late-onset formsRecurrent attacks of coma or lethargy with ataxia can occur in childhood or even in adolescence or adulthood. These episodes may be frequent, though in between these the child is entirely normal. These attacks are precipitated by conditions that enhance protein catabolism (trauma, infection etc

  20. Nephrogenic systemic fibrosis: late skin manifestations

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Marckmann, Peter; Rossen, Kristian

    2009-01-01

    BACKGROUND: Nephrogenic systemic fibrosis (NSF) is a serious disease that occurs in patients with severe renal disease and is believed to be caused by gadolinium-containing contrast agents. A detailed description of the late skin manifestations of NSF is important to help dermatologists and nephr......BACKGROUND: Nephrogenic systemic fibrosis (NSF) is a serious disease that occurs in patients with severe renal disease and is believed to be caused by gadolinium-containing contrast agents. A detailed description of the late skin manifestations of NSF is important to help dermatologists...... confluent dermal plaques with thickening and hardening. In contrast, 3 patients presented with wrinkled, redundant skin as seen in cutis laxa. Patients with NSF had significantly poorer scores than control patients on the Daily Life Quality Index (mean [SD], 11. 4 [7.4] vs 1.5 [2. 3]; P ...: This descriptive case series of patients with NSF gives a detailed clinical picture of the skin manifestations late in the disease. It demonstrates that the clinical picture in the late stage has a varied presentation and that NSF has a significant effect on the quality of life....

  1. Cardiopulmonary Manifestations of Ankylosing Spondylitis

    Science.gov (United States)

    Momeni, Mahnaz; Taylor, Nora; Tehrani, Mahsa

    2011-01-01

    Ankylosing spondylitis is a chronic inflammatory condition that usually affects young men. Cardiac dysfunction and pulmonary disease are well-known and commonly reported extra-articular manifestation, associated with ankylosing spondylitis (AS). AS has also been reported to be specifically associated with aortitis, aortic valve diseases, conduction disturbances, cardiomyopathy and ischemic heart disease. The pulmonary manifestations of the disease include fibrosis of the upper lobes, interstitial lung disease, ventilatory impairment due to chest wall restriction, sleep apnea, and spontaneous pneumothorax. They are many reports detailing pathophysiology, hypothesized mechanisms leading to these derangements, and estimated prevalence of such findings in the AS populations. At this time, there are no clear guidelines regarding a stepwise approach to screen these patients for cardiovascular and pulmonary complications. PMID:21547038

  2. Unusual clinical manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Bal A

    2005-01-01

    Full Text Available Leptospirosis has protean clinical manifestations. The classical presentation of the disease is an acute biphasic febrile illness with or without jaundice. Unusual clinical manifestations may result from involvement of pulmonary, cardiovascular, neural, gastrointestinal, ocular and other systems. Immunological phenomena secondary to antigenic mimicry may also be an important component of many clinical features and may be responsible for reactive arthritis. Leptospirosis in early pregnancy may lead to fetal loss. There are a few reports of leptospirosis in HIV- infected individuals but no generalisation can be made due to paucity of data. It is important to bear in mind that leptospiral illness may be a significant component in cases of dual infections or in simultaneous infections with more than two pathogens.

  3. Cardiopulmonary Manifestations of Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Mahnaz Momeni

    2011-01-01

    Full Text Available Ankylosing spondylitis is a chronic inflammatory condition that usually affects young men. Cardiac dysfunction and pulmonary disease are well-known and commonly reported extra-articular manifestation, associated with ankylosing spondylitis (AS. AS has also been reported to be specifically associated with aortitis, aortic valve diseases, conduction disturbances, cardiomyopathy and ischemic heart disease. The pulmonary manifestations of the disease include fibrosis of the upper lobes, interstitial lung disease, ventilatory impairment due to chest wall restriction, sleep apnea, and spontaneous pneumothorax. They are many reports detailing pathophysiology, hypothesized mechanisms leading to these derangements, and estimated prevalence of such findings in the AS populations. At this time, there are no clear guidelines regarding a stepwise approach to screen these patients for cardiovascular and pulmonary complications.

  4. Orofacial manifestations of systemic sclerosis.

    Science.gov (United States)

    Veale, B J; Jablonski, R Y; Frech, T M; Pauling, J D

    2016-09-23

    Systemic sclerosis (SSc) is a multisystem disease of unknown aetiology characterised by microangiopathy, dysregulated immune function and tissue remodelling, which commonly involves the oral cavity. Orofacial manifestations of SSc contribute greatly to overall disease burden and yet are regularly overlooked and under-treated. This may reflect a pre-occupation amongst rheumatology clinicians on potentially life-threatening internal organ involvement, but is also a consequence of insufficient engagement between rheumatologists and dental professionals. A high proportion of SSc patients report difficulty accessing a dentist with knowledge of the disease and there is recognition amongst dentists that this could impact negatively on patient care. This review shall describe the clinical features and burden of orofacial manifestations of SSc and the management of such problems. The case is made for greater collaborative working between rheumatologists and dental professionals with an interest in SSc in both the research and clinical setting.

  5. ORBITAL MANIFESTATIONS OF SINUS DISEASE

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    Jyothirmayi

    2015-01-01

    Full Text Available AIM : To study the orbital manifestations in patients with sinus disease. METHODS : Patients wit h paranasal sinus disease presenting to OPD at Government ENT Hospital, AMC, Visakhapatnam from January 2012 to June 2014 were screened for orbital manifestations. Out of these, thirteen patients with orbital disease were referred to GREH, AMC, Visakhapatn am and were thoroughly investigated and managed appropriately. RESULTS : Out of the 14 patients 4 were female and 10 were male. Age ranged from 19 years to 70 years. 5 had maxillary sinus disease (4 - carcinoma and 1 case of mucormycosis. Frontal sinus dis ease was seen in two patients, one fibrous dysplasia and one malignancy. Five patients had ethmoidal sinus disease of which three patients were found to have ethmoidal sinus tumour (Malignant melanoma, Squamous cell Carcinoma. More than two sinuses were i nvolved in 2 patients. CONCLUSIONS : Early screening of patients with sinus disease by an Ophthalmologist can help in preventing severe vision threatening orbital complications.

  6. Some Manifestations of Japanese Exclusionism

    Directory of Open Access Journals (Sweden)

    Liang Morita

    2015-08-01

    Full Text Available The Japanese subscribe to ethnic nationalism, which is an ideology with the aim to develop an ethnically exclusive and homogeneous nationhood. One manifestation of ethnic nationalism is the belief that Japan is, or should be, a mono-ethnic society. Ethnic nationalism is manifested in the exclusionary attitude or opinion of the Japanese. In the context of foreigners living in Japan, the exclusionary attitude or opinion of the Japanese often translates into the insistence that foreigners should do things the Japanese way. This is unfriendly to foreigners living in Japan, to say the least. This article illustrates how unwelcoming and inconvenient Japanese exclusionism can be by using two examples that directly affect foreigners: housing and discrimination against foreigners.

  7. Breast manifestations of systemic diseases

    Directory of Open Access Journals (Sweden)

    Dilaveri CA

    2012-02-01

    Full Text Available Christina A Dilaveri, Maire Brid Mac Bride, Nicole P Sandhu, Lonzetta Neal, Karthik Ghosh, Dietlind L Wahner-RoedlerDivision of General Internal Medicine, Mayo Clinic, Rochester, MN, USAAbstract: Although much emphasis has been placed on the primary presentations of breast cancer, little focus has been placed on how systemic illnesses may affect the breast. In this article, we discuss systemic illnesses that can manifest in the breast. We summarize the clinical features, imaging, histopathology, and treatment recommendations for endocrine, vascular, systemic inflammatory, infectious, and hematologic diseases, as well as for the extramammary malignancies that can present in the breast. Despite the rarity of these manifestations of systemic disease, knowledge of these conditions is critical to the appropriate evaluation and treatment of patients presenting with breast symptoms.Keywords: breast, endocrine, hematologic, infectious, vascular

  8. Rheumatic manifestations of inflammatory bowel disease

    Institute of Scientific and Technical Information of China (English)

    Tatiana Sofía Rodríguez-Reyna; Cynthia Martínez-Reyes; Jesús Kazúo Yamamoto-Furusho

    2009-01-01

    This article reviews the literature concerning rheumatic manifestations of inflammatory bowel disease(IBD), including common immune-mediated pathways,frequency, clinical course and therapy. Musculoskeletal complications are frequent and well-recognized manifestations in IBD, and affect up to 33% of patients with IBD. The strong link between the bowel and the osteo-articular system is suggested by many clinical and experimental observations, notably in HLA-B27 transgenic rats. The autoimmune pathogenic mechanisms shared by IBD and spondyloarthropathies include genetic susceptibility to abnormal antigen presentation,aberrant recognition of self, the presence of autoantibodies against specific antigens shared by the colon and other extra-colonic tissues, and increased intestinal permeability. The response against microorganisms may have an important role through molecular mimicry and other mechanisms. Rheumatic manifestations of IBD have been divided into peripheral arthritis, and axial involvement, including sacroiliitis,with or without spondylitis, similar to idiopathic ankylosing spondylitis. Other periarticular features can occur,including enthesopathy, tendonitis, clubbing, periostitis,and granulomatous lesions of joints and bones.Osteoporosis and osteomalacia secondary to IBD and iatrogenic complications can also occur. The management of the rheumatic manifestations of IBD consists of physical therapy in combination with local injection of corticosteroids and nonsteroidal anti-inflammatory drugs; caution is in order however, because of their possible harmful effects on intestinal integrity, permeability,and even on gut inflammation. Sulfasalazine,methotrexate, azathioprine, cyclosporine and leflunomide should be used for selected indications. In some cases, tumor necrosis factor-α blocking agents should be considered as first-line therapy.

  9. Diverse clinical manifestations of pheochromocytomas.

    Science.gov (United States)

    Badui, E; Mancilla, R; Szymanski, J J; Garcia-Rubi, D; Estañol, B

    1982-03-01

    Many difficulties are encountered by clinicians in attempting to diagnose pheochromocytomas. We describe several patients with unusual clinical features. These include sudden death, cerebral hemorrhage, refractory congestive heart failure, acute abdominal pain, and hypercalcemia. In 2 patients, the rare association of this tumor and pregnancy was observed. Two subjects had sudden death, 1 during a pneumoencephalogram and another during an epidural block. The clinicians should be aware of these manifestations of pheochromocytomas.

  10. Clinical manifestations of sleep apnea

    OpenAIRE

    Stansbury, Robert C.; Strollo, Patrick J.

    2015-01-01

    Obstructive sleep apnea (OSA) may manifest in a number of ways from subtle intrusion into daily life to profound sleepiness, snoring, witnessed apneas and other classic symptoms. Although there is increasing evidence suggesting OSA can adversely affect health in a variety of ways, this disorder remains underdiagnosed. The most well-escribed health consequences of OSA relate to the cardiovascular system. Hypertension and arrhythmias have a strong association with OSA, and evidence suggests tha...

  11. Infrequent cardiac manifestations of sarcoidosis.

    Science.gov (United States)

    Ashraf, Said; Briasoulis, Alexandros; Afonso, Luis

    Cardiac sarcoidosis (CS) is found in 2-7% of patients with systemic sarcoidosis (SS). Its diagnosis and treatment is challenging, notwithstanding the poor prognosis and treatment. Hereby, we present a case of systemic sarcoidosis with rare cardiac manifestations of severe mitral incompetence and large coronary aneurysm in a previously healthy woman. She underwent successful mitral valve replacement and coronary artery bypass surgery and was maintained on low dose glucocorticoid therapy. Copyright © 2016. Published by Elsevier Inc.

  12. Systemic diseases with cutaneous manifestations.

    Science.gov (United States)

    Merchant, S R; Taboada, J

    1995-07-01

    The purpose of this article is to briefly discuss the following cutaneous manifestations of selected systemic diseases: poxvirus; feline leukemia virus (FeLV); feline immunodeficiency virus (FIV); herpesvirus; calcivirus; pseudorabies; plague; tularemia; toxoplasmosis; leishmania; hypothyroidism; hyperthyroidism; hyperadrenocorticism; diabetes mellitus; acromegaly; thallium poisoning; pancreatic disease; hypereosinophilic syndrome; mucopolysaccharidosis; and pansteatitis. Recognition of these cutaneous signs may help alert the clinician to the possibility of an internal disorder so that the appropriate diagnostic tests can be considered.

  13. Respiratory manifestations in endocrine diseases

    OpenAIRE

    LENCU, CODRU?A; ALEXESCU, TEODORA; PETRULEA, MIRELA; LENCU, MONICA

    2016-01-01

    The control mechanisms of respiration as a vital function are complex: voluntary ? cortical, and involuntary ? metabolic, neural, emotional and endocrine. Hormones and hypothalamic neuropeptides (that act as neurotrasmitters and neuromodulators in the central nervous system) play a role in the regulation of respiration and in bronchopulmonary morphology. This article presents respiratory manifestations in adult endocrine diseases that evolve with hormone deficit or hypersecretion. In hyperthy...

  14. Imaging Manifestations of Thoracic Tuberculosis.

    Science.gov (United States)

    Restrepo, Carlos Santiago; Katre, Rashmi; Mumbower, Amy

    2016-05-01

    Despite significant improvements in the diagnosis and treatment of tuberculosis achieved during the last 3 decades, tuberculosis still remains one of the deadliest communicable diseases worldwide. Tuberculosis is still present in all regions of the world, with a more significant impact in developing countries. This article reviews the most common imaging manifestations of primary and postprimary tuberculosis, their complications, and the critical role of imaging in the diagnosis and follow-up of affected patients.

  15. Atypical Neurological Manifestations Of Hypokalemia

    Directory of Open Access Journals (Sweden)

    pal P K

    2004-01-01

    Full Text Available A part from the well-established syndrome of motor paralysis, hypokalemia may present with atypical neurological manifestations, which are not well documented in literature. Methods: We treated 30 patients of hypokalemia whose neurological manifestations improved after corrections of hypokalemia. A retrospective chart review of the clinical profile was done with emphasis on the evolution of symptoms and occurrence of unusual manifestations. Results: Twenty-eight patients had subacute quadriparesis with duration of symptoms varying from 10hrs to 7 days and two had slowly progressive quadriparesis. Fifty percent of patients had more than one attack of paralysis. Early asymmetric weakness (11, stiffness and abnormal posture of hands (7, predominant bibrachial weakness (4, distal paresthesias (4, hemiparesthesia (1, hyperreflexia(4, early severe weakness of neck muscles (3, chorea (1, trismus (1,and, retention of urine (1 were the unusual features observed. The means level of serum potassium on admission was 2.1+0.6mEq/L.and the serum creatine kinase was elevated in 14 out of 17 patients. All patients except two had complete recovery.

  16. Neurological manifestations of thoracic myelopathy.

    Science.gov (United States)

    Takenaka, Shota; Kaito, Takashi; Hosono, Noboru; Miwa, Toshitada; Oda, Takenori; Okuda, Shinya; Yamashita, Tomoya; Oshima, Kazuya; Ariga, Kenta; Asano, Masatoshi; Fuchiya, Tsuyoshi; Kuroda, Yusuke; Nagamoto, Yukitaka; Makino, Takahiro; Yamazaki, Ryoji; Yonenobu, Kazuo

    2014-07-01

    Investigation of preoperative manifestations of thoracic myelopathy in a large population has not been reported. The aim of this study was to identify symptoms specific to anatomical pathology or compressed segments in thoracic myelopathy through investigation of preoperative manifestations. Subjects were 205 patients [143 men, 62 women; mean age, 62.2 (range 21-87 years)] with thoracic myelopathy who underwent surgery at our affiliate institutions from 2000 to 2011. The disease distribution included ossification of the ligamentum flavum (OLF) in 106 patients, ossification of the posterior longitudinal ligament (OPLL) in 17, OLF with OPLL in 17, intervertebral disc herniation (IDH) in 23, OLF with IDH in 3, and spondylosis in 39. We assessed (1) initial and preoperative complaints, (2) neurological findings, (3) Japanese Orthopaedic Association scores (JOA, full score, 11 points), (4) the compressed segments, and (5) preoperative duration. Multivariate analyses were performed to examine potential relationships between preoperative manifestations and anatomical pathology or compressed segments. The multivariate analyses revealed relationships between lower limb muscle weakness and T10/11 anterior compression; lower limb pain and T11/12 anterior compression; low back pain and T11/12 compression; and hyporeflexia in the patellar tendon reflex/foot drop and T12/L1 anterior compression. This study elucidated symptoms specific to anatomical pathology or compressed segments in thoracic myelopathy. These relationships can be helpful in the initial investigation of thoracic diseases, although additional measures such as MRI or CT are necessary for definitive diagnosis.

  17. Thoracic manifestation of tuberculosis; Thorakale Manifestation der Tuberkulose

    Energy Technology Data Exchange (ETDEWEB)

    Kienzl-Palma, D.; Prosch, H. [Medizinische Universitaet Wien, Abteilung fuer Allgemeine Radiologie und Kinderradiologie, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Wien (Austria)

    2016-10-15

    Tuberculosis (TB) is a granulomatous disease caused by Mycobacterium tuberculosis and transmission is via an airborne route by droplet infection. In the majority of cases patients have thoracic TB, which most frequently presents with hilar lymphadenopathy and pulmonary manifestation. Due to the rise in incidence of TB in central Europe to be expected over the coming years, it is essential to be acquainted with the radiological manifestations of pulmonary TB, particularly to be able to discriminate active from inactive TB. Due to the use of molecular techniques entailing DNA fingerprinting, the traditional classification of TB in primary and postprimary TB is being challenged. These genetic studies have revealed that variations in the clinical and radiographic appearance of TB are mainly affected by the immune status of the patients. Due to the low prevalence of TB in central Europe and the wide variation of radiological presentations, the diagnosis and therapy of TB is often delayed. In this article, the radiographic manifestations of thoracic TB are summarized and discussed. Together with the medical history and bacteriological tests, chest X-ray imaging and computed tomography (CT) play a major role not only in the detection of TB but also in the follow-up during and after therapy. Chest X-radiographs should be the primary diagnostic method in patients with suspected TB in screening as well as for diagnosis and therapy monitoring. The use of CT is more sensitive than chest radiographs and is frequently performed after chest radiographs to obtain detailed information about subtle parenchymal changes or lymph node manifestation. When active TB is suspected CT should be performed. Tree in bud, lobular consolidations, centrilobular nodules, cavities and ground-glass opacification are typical changes in active TB. (orig.) [German] Tuberkulose (Tbc) ist eine durch Troepfchen uebertragene granulomatoese Infektionserkrankung, die durch das Mycobacterium tuberculosis

  18. [Neuropsychiatric manifestations ushering pernicious anemia].

    Science.gov (United States)

    Mrabet, S; Ellouze, F; Ellini, S; Mrad, M F

    2015-12-01

    Biermer disease or pernicious anemia is an autoimmune atrophic gastritis characterized by the lack of secretion of gastric intrinsic factor. This leads to an insufficient absorption of vitamin B12 in the ileum. Clinical manifestations are mainly hematologic. Neuropsychiatric manifestations are known but are less frequent especially early in the disease. Inaugural neuropsychiatric arrays are rare and various thus making diagnosis difficult. In this article, we report through two clinical cases different neuropsychiatric manifestations revealing pernicious anemia. Mrs. C.O., aged 56, presented after surgery for gallstones, an acute psychiatric array associated with gait disorders. She had no history of neurological or psychiatric problems. The psychiatric interview revealed delirious syndrome, depressive symptoms and anxiety. Neurological examination noted a flaccid paraplegia with peripheral neuropathic syndrome and myoclonus in the upper limbs. At the full blood count, a macrocytosis (VGM: 112.2fl) without anemia was found. The level of vitamin B12 in the blood was low. Cerebro-spinal MRI was suggestive of a neuro-Biermer and showed hyper signal in the cervical cord on T2-weighted sagittal section. In axial section, hyper signal appears at the posterior columns in the form of V. There were no brain abnormalities. A sensorimotor axonal polyneuropathy was diagnosed. The patient received vitamin B12 intramuscularly for ten days associated with neuroleptic treatment. Mrs. R.M., aged 40, was brought to the psychiatry consultation for acute behavioral disorders progressively worsening over a month. An anxiety syndrome, depressive syndrome and delirious syndrome were identified. Neurological examination showed a posterior cordonal syndrome with quadripyramidal syndrome. Full blood count showed a macrocytic anemia. Serum B12 level was collapsed. Cerebro-spinal MRI was normal. She received vitamin B12 with clinical and biological improvement. Features of pernicious anemia

  19. Cardiac manifestations in systemic sclerosis

    Institute of Scientific and Technical Information of China (English)

    Sevdalina; Lambova

    2014-01-01

    Primary cardiac involvement, which develops as a direct consequence of systemic sclerosis(SSc), may manifest as myocardial damage, fibrosis of the conduction system, pericardial and, less frequently, as valvular disease. In addition, cardiac complications in SSc may develop as a secondary phenomenon due to pulmonary arterial hypertension and kidney pathology. The prevalence of primary cardiac involvement in SSc is variable and difficult to determine because of the diversity of cardiac manifestations, the presence of subclinical periods, the type of diagnostic tools applied, and the diversity of patient populations. When clinically manifested, cardiac involvement is thought to be an important prognostic factor. Profound microvascular disease is a pathognomonic feature of SSc, as both vasospasm and structural alterations are present. Such alterations are thought to predict macrovascular atherosclerosis over time. There are contradictory reports regarding the prevalence of atherosclerosis in SSc. According to some authors, the prevalence of atherosclerosis of the large epicardial coronary arteries is similar to that of the general population, in contrast with other rheumatic diseases such as rheumatoid arthritis and systemic lupus erythematosus. However, the level of inflammation in SSc is inferior. Thus, the atherosclerotic process may not be as aggressive and not easily detectable in smaller studies. Echocardiography(especially tissue Doppler imaging), single-photon emission computed tomography, magnetic resonance imaging and cardiac computed tomography are sensitive techniques for earlier detection of both structural and functional scleroderma-related cardiac pathologies. Screening for subclinical cardiac involvement via modern, sensitive tools provides an opportunity for early diagnosis and treatment, which is of crucial importance for a positive outcome.

  20. ORAL MANIFESTATIONS OF HEPATITIS C VIRUS

    Directory of Open Access Journals (Sweden)

    Vladimir E. Panov

    2013-10-01

    Full Text Available Hepatitis C virus (HCV infection is a serious public health problem. New infections continue to occur, and morbidity and mortality are increasing. The date reported that 3% of infected world population are affected.Morbidity associated with hepatitis C virus infection can involve a variety of extrahepatic conditions including the oral region. Some of the oral manifestation are oral disease like lichen planus and Sjögren-like sialadenitis , other affects the dental status, and side effect of the virus therapy. The aim of this review is to summarize the oral sings, accompanying hepatitis C virus.

  1. Pulmonary manifestations of systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kee Hyuk; Choi, Yo Won; Jeon, Seok Chol; Park, Choong Ki; Joo, Kyung Bin; Hahm, Chang Kok; Lee, Seung Ro [College of Medicine, Hanyang Univ., Seoul (Korea, Republic of)

    2004-02-01

    Pulmonary involvement is more common in systemic lupus erythematosus (SLE) than in any other connective tissue disease, and more than half of patients with SLE suffer from respiratory dysfunction during the course of their illness. Although sepsis and renal disease are the most common causes of death in SLE, lung disease is the predominant manifestation and is an indicator of overall prognosis. Respiratory disease may be due to direct involvement of the lung or as a secondary consequence of the effect of the disease on other organ systems.

  2. Cutaneous manifestations of chikungunya fever.

    Science.gov (United States)

    Seetharam, K A; Sridevi, K; Vidyasagar, P

    2012-01-01

    Chikungunya fever, a re-emerging RNA viral infection produces different cutaneous manifestations in children compared to adults. 52 children with chikungunya fever, confirmed by positive IgM antibody test were seen during 2009-2010. Pigmentary lesions were common (27/52) followed by vesiculobullous lesions (16/52) and maculopapular lesions (14/52). Vesiculobullous lesions were most common in infants, although rarely reported in adults. Psoriasis was exacerbated in 4 children resulting in more severe forms. In 2 children, guttate psoriasis was observed for the first time.

  3. Neurological manifestation of colonic adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Uzair Chaudhary

    2012-04-01

    Full Text Available Paraneoplastic neurologic disorders are extremely rare in cancer patients and are most commonly associated with certain tumors, such as ovarian cancer, small cell lung cancer, and breast cancer. We report here a paraneoplastic neurological syndrome in a 53-year-old man with colonic adenocarcinoma with a solitary liver metastasis. His paraneoplastic syndrome was successfully treated by methylprednisolone and primary oncologic therapies including neoadjuvant chemotherapy and definitive surgery. This is also the first documented case of simultaneous manifestation of a sensory neuropathy and limbic encephalitis with colon cancer.

  4. Gaucher disease and bone manifestations.

    Science.gov (United States)

    Marcucci, Gemma; Zimran, Ari; Bembi, Bruno; Kanis, John; Reginster, Jean-Yves; Rizzoli, Renè; Cooper, Cyrus; Brandi, Maria Luisa

    2014-12-01

    Gaucher disease is a relatively rare metabolic disease caused by the inherited deficiency of the lysosomal enzyme glucocerebrosidase. Gaucher disease affects multiple organs, among which is the skeleton. Bone involvement occurs frequently in Gaucher disease, and is one of its most debilitating features, reducing the quality of life of patients. Bone status is an important consideration for treatment to ameliorate symptoms and reduce the risk of irreversible complications. We have conducted a systematic review of all the various aspects of Gaucher disease, focusing on different skeletal manifestations, pathophysiology of bone alterations, clinical symptoms, and current diagnostic and therapeutic approaches.

  5. [Corneal manifestations in systemic diseases].

    Science.gov (United States)

    Zarranz Ventura, J; De Nova, E; Moreno-Montañés, J

    2008-01-01

    Systemic diseases affecting the cornea have a wide range of manifestations. The detailed study of all pathologies that cause corneal alteration is unapproachable, so we have centered our interest in the most prevalent or characteristic of them. In this paper we have divided these pathologies in sections to facilitate their study. Pulmonar and conective tissue (like colagen, rheumatologic and idiopathic inflamatory diseases), dermatologic, cardiovascular, hematologic, digestive and hepatopancreatic diseases with corneal alteration are described. Endocrine and metabolic diseases, malnutrition and carential states are also studied, as well as some otorhinolaryngologic and genetic diseases that affect the cornea. Finally, a brief report of ocular toxicity induced by drugs is referred.

  6. Study of ocular manifestations in children of thalassemia

    OpenAIRE

    Dhara K. Gosai; K. M. Mehariya; Jigarkumar B. Gosai

    2014-01-01

    Background: Purpose of current study was to study the ocular manifestations in beta-thalassemia major patients and assess the ocular side-effects of iron chelating agents. Methods: Cross sectional study included 45 beta Thalassemia major patients from age group of 6months to 12 years were taken. Full medical history, thorough physical examinations were done to all patients groups, and ophthalmological examination to determine the prevalence of ocular manifestations for all patient groups a...

  7. Cutaneous manifestations of inflammatory bowel disease

    Directory of Open Access Journals (Sweden)

    Al Roujayee Abdulaziz

    2007-01-01

    Full Text Available Inflammatory bowel disease (IBD has many extraintestinal manifestations, and skin lesions are one of the most frequently described extraintestinal findings. Reports indicate an incidence of cutaneous manifestations ranging from 2 to 34%, Cutaneous manifestations are usually related to the activity of the bowel disease but may have an independent course. In this review we aim to address the various cutaneous manifestations associated with IBD, their impact on the disease course, and the treatment options available.

  8. Atypical Manifestation of Vestibular Schwannoma

    Directory of Open Access Journals (Sweden)

    Webster, Guilherme

    2013-09-01

    Full Text Available Introduction: Vestibular schwannoma (also known as acoustic neuroma is a benign tumor whose cells are derived from Schwann sheaths, which commonly occurs from the vestibular portion of the eighth cranial nerve. Furthermore, vestibular schwannomas account for ∼8% of intracranial tumors in adults and 80 to 90% of tumors of the cerebellopontine angle. Its symptoms are varied, but what stands out most is a unilateral sensorineural hearing loss, with a low index of speech recognition. Objective: Describe an atypical manifestation of vestibular schwannoma. Case Report: The 46-year-old woman had vertigo and binaural hearing loss and fullness, with ear, nose, and throat examination suggestive of cochlear injury. After 6 months, the patient developed worsening of symptoms and onset of right unilateral tinnitus. In further exams the signs of cochlear damage remained, except for the vestibular test (hyporeflexia. Magnetic resonance imaging showed an expansive lesion in the right cerebellopontine angle. Discussion: This report warns about the atypical manifestations of vestibular schwannoma, which must always be remembered in investigating and diagnosing hearing loss.

  9. Cutaneous manifestations of internal malignancy

    Directory of Open Access Journals (Sweden)

    A Ayyamperumal

    2012-01-01

    Full Text Available Background: Many malignancies affecting the internal organs display cutaneous manifestations which may be either specific (tumor metastases or nonspecific lesions. Aims: The study is aimed at determining the frequency and significance of cutaneous manifestations among patients with internal malignancy. Materials and Methods: 750 cases of proven internal malignancy, who attended a cancer chemotherapy center in South India, were studied. Specific infiltrates were confirmed by histopathology, fine needle aspiration cytology (FNAC and marker studies. Results: Out of the 750 patients with internal malignancy, skin changes were seen in a total of 52 (6.93% patients. Conclusion: Cutaneous metastases (specific lesions were seen in 20 patients (2.66%: contiguous in 6 (0.8%, and non-contiguous in 14 (1.86%. Nonspecific skin changes were seen in 32 patients (4.26%. None of our patients presented with more than one type of skin lesions. Herpes zoster was the most common nonspecific lesion noticed in our patients, followed by generalized pruritus, multiple eruptive seborrheic keratoses, bullous disorder, erythroderma, flushing, purpura, pyoderma gangrenosum, insect bite allergy and lichenoid dermatitis.

  10. The effect of memory on relaxation in a scalar field theory

    CERN Document Server

    Ikeda, T

    2004-01-01

    We derive a kinetic equation with a non-Markovian collision term which includes a memory effect, from Kadanoff-Baym equations in $\\phi^4$ theory within the three-loop level for the two-particle irreducible (2PI) effective action. The memory effect is incorporated into the kinetic equation by a generalized Kadanoff-Baym ansatz.Based on the kinetic equations with and without the memory effect, we investigate an influence of this effect on decay of a single particle excitation with zero momentum in 3+1 dimensions and the spatially homogeneous case. Numerical results show that, while the time evolution of the zero mode is completely unaffected by the memory effect due to a separation of scales in the weak coupling regime, this effect leads first to faster relaxation than the case without it and then to slower relaxation as the coupling constant increases.

  11. 40 CFR 761.210 - Manifest discrepancies.

    Science.gov (United States)

    2010-07-01

    ... PROHIBITIONS PCB Waste Disposal Records and Reports § 761.210 Manifest discrepancies. (a) Manifest discrepancies are differences between the quantity or type of PCB waste designated on the manifest or shipping paper and the quantity or type of PCB waste actually delivered to and received by a designated facility...

  12. The big-fish-little-pond effect on academic self-concept: a comparison of GAPIM and a latent-manifest contextual model (SRA)

    NARCIS (Netherlands)

    Zurbriggen, Carmen; Gommans, R.; Venetz, Martin

    2016-01-01

    The goal of this paper was to compare two methods for the analysis of group composition effects using the classical big-fish-little-pond effect (BFLPE) as an example. The BFLPE (Marsh, 1987) is a well-known and frequently investigated group composition effect in educational research (e.g. Seaton, Ma

  13. Acute Coronary Syndrome Manifesting as an Adverse Effect of All-trans-Retinoic Acid in Acute Promyelocytic Leukemia: A Case Report with Review of the Literature and a Spotlight on Management

    Directory of Open Access Journals (Sweden)

    K. Govind Babu

    2016-01-01

    Full Text Available Background. Acute promyelocytic leukemia is characterized by t(15;17. This leads to the formation of PML/RARα which blocks the differentiation of blasts at the stage of promyelocytes. This is reversed by all-trans-retinoic acid (ATRA, a vitamin A derivative. Acute myocardial ischemia is a rare side effect of ATRA. Case Report. We report a case of acute coronary syndrome manifesting as an adverse effect of ATRA in a lady with APL who had no other risk factors for cardiovascular disease. Conclusions. We emphasize the need for high index of suspicion for the diagnosis of this entity. In the light of this case, the rare instances of ATRA associated acute myocardial ischemia recorded in the literature and the options available for treatment of acute promyelocytic leukemia sans ATRA have been reviewed.

  14. Electrode and device problems: manifestation and management.

    Science.gov (United States)

    Twomey, T; Archbold, S

    1997-11-01

    A total of 119 children were implanted with the Nucleus 22 implant on the Nottingham program by March 1996. Twenty-five (i.e. 21%) of these had an electrophysiologically confirmed fault on at least 1 channel and 6 (i.e. 5%) had experienced total device failure. How these problems were first manifested and what the subsequent effects were on the child and family were determined by means of questionnaires and detailed examination of clinical notes. Our findings indicated that 76% of all internal device faults were initially detected in tuning or electrophysiological measurement. All parents expressed deep anxiety about the threat of device failure; cases of total failure occurring over a long period of time resulted in the greatest distress and effect on the family. Recommendations are made for companies to assist clinics in minimizing such effects.

  15. Gastrointestinal manifestations of food allergies.

    Science.gov (United States)

    Wolfe, Jaime Liou; Aceves, Seema S

    2011-04-01

    The rates of eosinophilic gastrointestinal disorders appear to be increasing. The most common of these is eosinophilic esophagitis (EoE) which is a clinicopathologic condition consisting of characteristic symptoms and endoscopic features accompanied by a pan-esophageal, acid resistant epithelial eosinophilia of greater than equal to 15 per high power field. Typical symptoms include dysphagia and abdominal pain. Typical endoscopic features include pallor, plaques, furrows, concentric rings. Complications include food impactions and strictures. EoE resolution with food elimination diets provides evidence that EoE is a food-antigen driven process. In vitro and microarray studies have identified specific immunologic factors underlying EoE pathogenesis. Other gastrointestinal manifestations of food intolerances/allergy include food protein induced enterocolitis syndrome.

  16. Atypical Cutaneous Manifestations in Syphilis.

    Science.gov (United States)

    Ivars Lleó, M; Clavo Escribano, P; Menéndez Prieto, B

    2016-05-01

    Although the diversity of the clinical manifestations of syphilis is well-known, atypical presentations can also occur. Such atypical presentations are associated with a high risk of transmission as a result of diagnostic confusion and treatment delays owing to the disease's ability to mimic other common skin diseases, deviate from classic clinical presentations, and adopt unique forms. Cases of atypical syphilis have been described most frequently in patients with concomitant human immunodeficiency virus (HIV) infection. Because the incidence of syphilis has been growing over recent years -particularly in patients with HIV co-infection- dermatologists need to be familiar with the less well-known clinical presentations of this venereal disease. Copyright © 2015 AEDV. Published by Elsevier España, S.L.U. All rights reserved.

  17. [Pulmonary manifestations in rheumatoid arthritis].

    Science.gov (United States)

    Morawska, Justyna; Domysławska, Izabela; Bagrowska, Magdalena; Sierakowski, Stanislaw

    2015-01-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by destructive cartilages, bones and other structures formed joints. RA belongs to connective tissue diseases represented by systemic nature, internal illness, extra-articular features and rapidly progress of atherosceirosis. The extra-articular complications cause the reduction of patient longevity. The frequency of symptoms in patient with RA and respiratory disorders occur in 10-20% of cases. Pulmonary complications are the second most common cause of premature of patient deaths. Respiratory disorders associated with RA are devided into 3 groups: infection, lung disease caused by drugs and pulmonary manifestation connected by RA. These last affect interstitial tissue, bronchioli, pulmonary vessels, pleura, also are presented by pulmonary rheumatoid nodules and pulmonary hypertension.

  18. Oropharyngeal dysphagia: manifestations and diagnosis.

    Science.gov (United States)

    Rommel, Nathalie; Hamdy, Shaheen

    2016-01-01

    Swallowing disorders (dysphagia) have been recognized by the WHO as a medical disability associated with increased morbidity, mortality and costs of care. With increasing survival rates and ageing of the population, swallowing disorders and their role in causing pulmonary and nutritional pathologies are becoming exceedingly important. Over the past two decades, the study of oropharyngeal dysphagia has been approached from various disciplines with considerable progress in understanding its pathophysiology. This Review describes the most frequent manifestations of oropharyngeal dysphagia and the clinical as well as instrumental techniques that are available to diagnose patients with dysphagia. However, the clinical value of these diagnostic tests and their sensitivity to predict outcomes is limited. Despite considerable clinical research efforts, conventional diagnostic methods for oropharyngeal dysphagia have limited proven accuracy in predicting aspiration and respiratory disease. We contend that incorporation of measurable objective assessments into clinical diagnosis is needed and might be key in developing novel therapeutic strategies.

  19. Mucocutaneous manifestations of Chikungunya fever

    Directory of Open Access Journals (Sweden)

    Bandyopadhyay Debabrata

    2010-01-01

    Full Text Available Chikungunya fever (CF is an arboviral acute febrile illness transmitted by the bite of infected Aedes mosquitoes. After a quiescence of more than three decades, CF has recently re-emerged as a major public health problem of global scale. CF is characterized by an acute onset of high fever associated with a severe disabling arthritis often accompanied by prominent mucocutaneous manifestations. The disease is usually self-limiting, but the joint symptoms and some of the cutaneous features may persist after the defervescence. A wide range of mucocutaneous changes has been described to occur in association with CF during the current epidemic. Besides a morbilliform erythema, hyperpigmentation, xerosis, excoriated papules, aphthous-like ulcers, vesiculobullous and lichenoid eruptions, and exacerbation of pre-existing or quiescent dermatoses had been observed frequently. These unusual features may help in the clinical differential diagnosis of acute viral exanthems mimicking CF.

  20. The Manifestly Gauge Invariant Exact Renormalisation Group

    CERN Document Server

    Rosten, O J

    2005-01-01

    We construct a manifestly gauge invariant Exact Renormalisation Group (ERG) whose form is suitable for computation in SU(N) Yang-Mills theory, beyond one-loop. An effective cutoff is implemented by embedding the physical SU(N) theory in a spontaneously broken SU(N|N) Yang-Mills theory. To facilitate computations within this scheme, which proceed at every step without fixing the gauge, we develop a set of diagrammatic techniques. As an initial test of the formalism, the one-loop SU(N) Yang-Mills beta-function, beta_1, is computed, and the standard, universal answer is reproduced. It is recognised that the computational technique can be greatly simplified. Using these simplifications, a partial proof is given that, to all orders in perturbation theory, the explicit dependence of perturbative $\\beta$-function coefficients, beta_n, on certain non-universal elements of the manifestly gauge invariant ERG cancels out. This partial proof yields an extremely compact, diagrammatic form for the surviving contributions t...

  1. Decoherence of two-qubit system in a non-Markovian squeezed reservoir

    Institute of Scientific and Technical Information of China (English)

    Wang Fa-Qiang; Zhang Zhi-Ming; Liang Rui-Sheng

    2009-01-01

    The decoherence of two initially entangled qubits coupled with a squeezed vacuum cavity separately is investigated exactly. The results show that, first, in principle, the disentanglement time decreases with the increase of squeeze parameter r, due to the augmenting of average photon number of every mode in the squeezed vacuum cavity. Second, there appear entanglement revivals after the complete disentanglement for the case of even parity initial Bell state, while there occur the entanglement decrcase and the entanglement revival before the complete disentanglement for the case of odd parity initial Bell state. The results are quite different from those for the case of qubits in a vacuum cavity.

  2. Non-Markovian memory in quantum process tomography and a preparation independent map

    CERN Document Server

    Modi, Kavan

    2010-01-01

    Recently it has been pointed out how differences in preparation procedures for quantum experiments can lead to non-trivial differences in the results of the experiment. The difference arise from the initial correlations between the system and environment. Therefore, any quantum experiment that is prone to the influences from the environment must be prepared carefully. In this paper, we study a quantum process tomography procedure that yields a result independent of the preparation procedure. We investigate the properties of this map and find an approach to distinguish the role of initial correlation in the dynamics of the system.

  3. Nonequilibrium Quantum Criticality and Non-Markovian Environment: Critical Exponent of a Quantum Phase Transition

    Science.gov (United States)

    Nagy, D.; Domokos, P.

    2015-07-01

    We show that the critical exponent of a quantum phase transition in a damped-driven open system is determined by the spectral density function of the reservoir. We consider the open-system variant of the Dicke model, where the driven boson mode and also the large N spin couple to independent reservoirs at zero temperature. The critical exponent, which is 1 if there is no spin-bath coupling, decreases below 1 when the spin couples to a sub-Ohmic reservoir.

  4. Dynamical Topological Symmetry Breaking as the Origin of Turbulence, Non-Markovianity, and Self-Similarity

    CERN Document Server

    Ovchinnikov, Igor V

    2012-01-01

    Here it is shown that the most general Parisi-Sourlas-Wu stochastic quantization procedure applied to any stochastic differential equation (SDE) leads to a Witten-type topological field theory - a model with a global topological Becchi-Rouet-Stora-Tyutin supersymmetry (Q-symmetry). Q-symmetry can be dynamically broken only by (anti-)instantons - ultimately nonlinear sudden tunneling processes of (creation)annihilation of solitons, e.g., avalanches in self-organized criticality (SOC) or (creation)annihilation of vortices in turbulent water. The phases with unbroken Q-symmetry are essentially markovian and can be understood solely in terms of the conventional Fokker-Plank evolution of the probability density. For these phases, Ito interpretation of SDEs and/or Martin-Siggia-Rose approximation of the stochastic quantization are applicable. SOC, turbulence, glasses, quenches etc. constitute the "generalized turbulence" category of stochastic phases with broken Q-symmetry. In this category, (anti-)instantons conde...

  5. A Gillespie algorithm for non-Markovian stochastic processes: Laplace transform approach

    CERN Document Server

    Masuda, Naoki

    2016-01-01

    The Gillespie algorithm provides statistically exact methods to simulate stochastic dynamics modelled as interacting sequences of discrete events including systems of biochemical reactions or earthquakes, networks of queuing processes or spiking neurons, and epidemic and opinion formation processes on social networks. Empirically, inter-event times of various human activities, in particular human communication, and some natural phenomena are often distributed according to long-tailed distributions. The Gillespie algorithm and its extant variants either assume the Poisson process, which produces exponentially distributed inter-event times, not long-tailed distributions, assume particular functional forms for time courses of the event rate, or works for non-Poissonian renewal processes including the case of long-tailed distributions of inter-event times but at a high computational cost. In the present study, we propose an innovative Gillespie algorithm for renewal processes on the basis of the Laplace transform...

  6. Direct measurements reveal non-Markovian fluctuations of DNA threading through a solid-state nanopore

    CERN Document Server

    Bell, Nicholas A W

    2016-01-01

    The threading of a polymer chain through a small pore is a classic problem in polymer dynamics and underlies nanopore sensing technology. However important experimental aspects of the polymer motion in a solid-state nanopore, such as an accurate measurement of the velocity variation during translocation, have remained elusive. In this work we analysed the translocation through conical quartz nanopores of a 7 kbp DNA double-strand labelled with six markers equally spaced along its contour. These markers, constructed from DNA hairpins, give direct experimental access to the translocation dynamics. On average we measure a 5% reduction in velocity during the translocation. We also find a striking correlation in velocity fluctuations with a decay constant of 100s of {\\mu}s. These results shed light on hitherto unresolved problems in the dynamics of DNA translocation and provide guidance for experiments seeking to determine positional information along a DNA strand.

  7. Reconstruction of the environmental correlation function from single emitter photon statistics: a non-Markovian approach

    CERN Document Server

    Shikerman, Faina; Pe'er, Avi

    2012-01-01

    We consider the two-level system approximation of a single emitter driven by a continuous laser pump and simultaneously coupled to the electromagnetic vacuum and to a thermal reservoir beyond the Markovian approximation. We discuss the connection between a rigorous microscopic theory and the phenomenological spectral diffusion approach, used to model the interaction of the emitter with the thermal bath, and obtained analytic expressions relating the thermal correlation function to the single emitter photon statistics.

  8. Ultrafast optical dynamics of HITCI in ethylene glycol. A non-Markovian Brownian oscillator description

    NARCIS (Netherlands)

    de Boeij, Wim P; Pshenichnikov, Maxim S.; Duppen, Koos; Wiersma, Douwe A.

    1994-01-01

    Femtosecond photon echo, chirped four-wave mixing and pump-probe experiments are reported, using a 13 fs cavity-dumped Ti: sapphire laser for excitation. It is shown that the optical dynamics of HITCI in ethylene glycol occurs on distinctly different time scales. The ultrafast solvent response is

  9. Non-Markovian Fermionic Stochastic Schr\\"{o}dinger Equation for Open System Dynamics

    CERN Document Server

    Shi, Wufu; Yu, Ting

    2012-01-01

    In this paper we present an exact Grassmann stochastic Schr\\"{o}dinger equation for the dynamics of an open fermionic quantum system coupled to a reservoir consisting of a finite or infinite number of fermions. We use this stochastic approach to derive the exact master equation for a fermionic system strongly coupled to electronic reservoirs. The generality and applicability of this Grassmann stochastic approach is justified and exemplified by several quantum open system problems concerning quantum decoherence and quantum transport for both vacuum and finite-temperature fermionic reservoirs. We show that the quantum coherence property of the quantum dot system can be profoundly modified by the environment memory.

  10. Diagonal time gating of stimulated photon echo : vibrational mode suppression in the non-Markovian limit

    NARCIS (Netherlands)

    Pshenichnikov, Maxim S.; Boeij, Wim P. de; Wiersma, Douwe A.

    1996-01-01

    In this contribution we show that enhanced mode suppression can be obtained by time-gating the stimulated photon echo (SPE) at the conventional echo time and in phase with the wave packet dynamics. This novel technique is demonstrated on a dye solution of DTTCI in ethylene glycol. As it was directly

  11. Non-Markovian Decay and Lasing Condition in an Optical Microcavity Coupled to a Structured Reservoir

    CERN Document Server

    Longhi, S

    2006-01-01

    The decay dynamics of the classical electromagnetic field in a leaky optical resonator supporting a single mode coupled to a structured continuum of modes (reservoir) is theoretically investigated, and the issue of threshold condition for lasing in presence of an inverted medium is comprehensively addressed. Specific analytical results are given for a single-mode microcavity resonantly coupled to a coupled resonator optical waveguide (CROW), which supports a band of continuous modes acting as decay channels. For weak coupling, the usual exponential Weisskopf-Wigner (Markovian) decay of the field in the bare resonator is found, and the threshold for lasing increases linearly with the coupling strength. As the coupling between the microcavity and the structured reservoir increases, the field decay in the passive cavity shows non exponential features, and correspondingly the threshold for lasing ceases to increase, reaching a maximum and then starting to decrease as the coupling strength is further increased. A ...

  12. A general class of spreading processes with non-Markovian dynamics

    CERN Document Server

    Nowzari, Cameron; Preciado, Victor M; Pappas, George J

    2015-01-01

    In this paper we propose a general class of models for spreading processes we call the $SI^*V^*$ model. Unlike many works that consider a fixed number of compartmental states, we allow an arbitrary number of states on arbitrary graphs with heterogeneous parameters for all nodes and edges. As a result, this generalizes an extremely large number of models studied in the literature including the MSEIV, MSEIR, MSEIS, SEIV, SEIR, SEIS, SIV, SIRS, SIR, and SIS models. Furthermore, we show how the $SI^*V^*$ model allows us to model non-Poisson spreading processes letting us capture much more complicated dynamics than existing works such as information spreading through social networks or the delayed incubation period of a disease like Ebola. This is in contrast to the overwhelming majority of works in the literature that only consider spreading processes that can be captured by a Markov process. After developing the stochastic model, we analyze its deterministic mean-field approximation and provide conditions for wh...

  13. On Clinical Manifestation and Therapeutic Effect of First Use of Triclabendazole Treatment of Fasciola%三氯苯达唑治疗人肝片形吸虫的临床疗效观察

    Institute of Scientific and Technical Information of China (English)

    顾伟; 邹静; 李芹翠; 杜茜茹; 焦建明

    2012-01-01

    目的:探讨肝片形吸虫感染的有效治疗方法。方法:对我院住院治疗的7例肝片形吸虫感染患者进行临床资料分析,研究其使用三氯苯达唑与其它抗寄生虫药物治疗的对比。结果:7例患者均有相同的临床表现,阿苯达唑、吡喹酮等药物治疗无效,三氯达苯唑有效。结论:通过这次肝片形吸虫感染的治疗和临床分析,三氯苯达唑是一种具有良好抗肝片形吸虫药效的药物,对今后治疗肝片形虫病有一定指导作用。%Objective: To explore the effective treatment of Fasciola hepatica infection.Methods: An analysis of the use of Triclabendazole treatment and other antiparasitic drugs in the clinical manifestations was made among 7 cases of Fasciola hepatica infection in patients with clinical data and treatment from our hospital,and the corresponding treatment programs were compared.Results: 7 patients had the same clinical manifestations,which were that Albendazole and Praziquantel drug therapy were ineffective,while Triclabendazole effective.Conclusion: Though the treatment of Fasciola hepatica infection,Triclabendazole,as a good drug of anti-Fasciola hepatica,has a role in guiding the future treatment of Fasciolasis hepatica.

  14. The effect of the external regulator's absence on children's speech use, manifested self-regulation, and task performance during learning tasks

    NARCIS (Netherlands)

    Agina, Adel M.; Agina, Adel Masaud; Kommers, Petrus A.M.; Steehouder, M.F.

    2011-01-01

    The present study was conducted to explore the effect of the absence of the external regulators on children’s use of speech (private/social), task performance, and self-regulation during learning tasks. A novel methodology was employed through a computer-based learning environment that proposed

  15. The effect of nonhuman’s versus human’s external regulation on children’s speech use, manifested self-regulation, and satisfaction during learning tasks

    NARCIS (Netherlands)

    Agina, Adel M.; Kommers, Piet A.M.; Steehouder, Michael F.

    2011-01-01

    Because of several analytical and methodological critiques on the findings and contexts of children’s private speech (PS), self-regulation learning (SRL), and thinking aloud (TA), the present study was conducted to shed new light on the effect of the nonhuman’s/computer’s versus human’s/teacher’s in

  16. The effect of the external regulator’s absence on children’s speech use, manifested self-regulation, and task performance during learning tasks

    NARCIS (Netherlands)

    Agina, Adel M.; Kommers, Piet A.M.; Steehouder, Michael F.

    2011-01-01

    The present study was conducted to explore the effect of the absence of the external regulators on children’s use of speech (private/social), task performance, and self-regulation during learning tasks. A novel methodology was employed through a computer-based learning environment that proposed thre

  17. [EEG manifestations in metabolic encephalopathy].

    Science.gov (United States)

    Lin, Chou-Ching K

    2005-09-01

    Normal brain function depends on normal neuronal metabolism, which is closely related to systemic homeostasis of metabolites, such as glucose, electrolytes, amino acids and ammonia. "Metabolic encephalopathy" indicates diffuse brain dysfunction caused by various systemic derangements. Electroencephalogram (EEG) is widely used to evaluate metabolic encephalopathy since 1937, when Berger first observed slow brain activity induced by hypoglycemia. EEG is most useful in differentiating organic from psychiatric conditions, identifying epileptogenicity, and providing information about the degree of cortical or subcortical dysfunction. In metabolic encephalopathy, EEG evolution generally correlates well with the severity of encephalopathy. However, EEG has little specificity in differentiating etiologies in metabolic encephalopathy. For example, though triphasic waves are most frequently mentioned in hepatic encephalopathy, they can also be seen in uremic encephalopathy, or even in aged psychiatric patients treated with lithium. Spike-and-waves may appear in hyper- or hypo-glycemia, uremic encephalopathy, or vitamin deficiencies, etc. Common principles of EEG changes in metabolic encephalopathy are (1) varied degrees of slowing, (2) assorted mixtures of epileptic discharge, (3) high incidence of triphasic waves, and (4), as a rule, reversibility after treatment of underlying causes. There are some exceptions to the above descriptions in specific metabolic disorders and EEG manifestations are highly individualized.

  18. Skin manifestations in autoinflammatory syndromes.

    Science.gov (United States)

    Braun-Falco, Markus; Ruzicka, Thomas

    2011-03-01

    Autoinflammatory diseases encompass a group of inflammatory diseases that are non-infectious, non-allergic, non-autoimmune and non-immunodeficient. The term was initially coined for a small group of familial periodic fever syndromes of which familial Mediterranean fever (FMF) is the most common and best known. Genetic and molecular analyses demonstrated for the majority of these diseases an impairment of inflammasomes to cause an increased activity of an interleukin-1-dependent inflammatory response. Over the last years an increasing number of either rare hereditary syndromes or acquired common diseases could be summarized under the designation of autoinflammatory disease, thus creating an emerging new rubric of inflammatory diseases. Many of them display cutaneous manifestations as both concomitant or more rarely main symptoms. To name some of them like erysipelas-like erythema in FMF; urticaria-like rashes in tumor necrosis factor receptor 1- or cryopyrin-associated periodic syndromes (TRAPS, CAPS), hyperimmunoglobulin D syndrome (HIDS) or Schnitzler syndrome; pyoderma gangrenosum and acne in PAPA syndrome; or behçetoid aphthous ulcerations in HIDS and PFAPA syndrome. Based on the new insights into pathogenesis one increasingly realizes the good response of these diseases to IL-1 antagonist therapies.

  19. Mucocutaneous manifestations of HIV infection

    Directory of Open Access Journals (Sweden)

    Shobhana A

    2004-03-01

    Full Text Available BACKGROUND AND AIMS: Human immunodeficiency virus (HIV is associated with various mucocutaneous features, which may be the first pointer towards the existence of HIV infection. This study was done to note the different mucocutaneous lesions present in the HIV population in eastern India. METHODS: Four hundred and ten HIV seropositive patients attending the outpatient and inpatient departments were included in the study. RESULTS: Out of 410 HIV positives, 40% had mucocutaneous involvement at presentation. The mean age of the study population was 29 years and male to female ratio was 2.5:1. The common mucocutaneous morbidities included oral candidiasis (36%, dermatophytosis and gingivitis (13% each, herpes zoster (6%, herpes simplex and scabies (5% each. A striking feature, noted in 36% males, was straightening of hairs. Genital herpes was the commonest genital ulcer disease. Lesions associated with declining immunity included oral candidiasis, oral hairy leukoplakia and herpes zoster with median CD4 counts of 98, 62 and 198/ L respectively. CONCLUSION: Early recognition of mucocutaneous manifestations and associated STDs help in better management of HIV/AIDS.

  20. Respiratory manifestations in endocrine diseases.

    Science.gov (United States)

    Lencu, Codruţa; Alexescu, Teodora; Petrulea, Mirela; Lencu, Monica

    2016-01-01

    The control mechanisms of respiration as a vital function are complex: voluntary - cortical, and involuntary - metabolic, neural, emotional and endocrine. Hormones and hypothalamic neuropeptides (that act as neurotrasmitters and neuromodulators in the central nervous system) play a role in the regulation of respiration and in bronchopulmonary morphology. This article presents respiratory manifestations in adult endocrine diseases that evolve with hormone deficit or hypersecretion. In hyperthyroidism, patients develop ventilation disorders, obstructive and central sleep apnea, and pleural collection. The respiratory abnormalities in hyperthyroidism as a result of the hypermetabolic action of thyroid hormones are hyperventilation, myopathy and cardiovascular involvement; recent studies have reported pulmonary arterial hypertension in Graves' disease, as a result of the association of several mechanisms. Thyroid hypertrophy can induce through compression of the upper airways dyspnea, stridor, wheezing and cough. The respiratory disorders in acromegaly are ventilatory dysfunction and sleep apnea, which contribute to an unfavorable evolution of the disease. Respiratory changes in parathyroid, adrenal and reproductive system diseases have been described. Respiratory disorders should be recognized, investigated and monitored by medical practitioners of various specialties (family physicians, internists, endocrinologists, pneumologists, cardiologists). They are frequently severe, causing an unfavorable evolution of the associated endocrine and respiratory disease.

  1. Rheumatological manifestations in diabetes mellitus.

    Science.gov (United States)

    Del Rosso, Angela; Cerinic, Marco Matucci; De Giorgio, Francesca; Minari, Chiara; Rotella, Carlo Maria; Seghieri, Giuseppe

    2006-11-01

    Rheumatological manifestations of Diabetes Mellitus may be classified in: non articular, articular and bone conditions. Among non articular conditions, diabetic cheiroarthropathy, frequent in type I diabetes, the most important disorder related to limited joint mobility, results in stiff skin and joint contractures. Adhesive capsulitis of the shoulder, flexor tenosynovitis, and Duputryen's and Peyronie's diseases are also linked to limited joint mobility. Diffuse skeletal hyperostosis, due to calcification at entheses, is frequent and early, particularly in type 2 diabetes. Neuropathies cause some non articular conditions, mainly neuropathic arthritis, a destructive bone and joint condition more common in type I diabetes. Algodistrophy, shoulder-hand and entrapment syndromes are also frequent. Mononeuropathy causes diabetic amyotrophy, characterised by painless muscle weakness. Among muscle conditions, diabetic muscle infarction is a rare, sometimes severe, condition. Among articular conditions, osteoarthritis is frequent and early in diabetes, in which also chondrocalcinosis and gout occur. Rheumatoid arthritis (RA) and diabetes I have a common genetic background and the presence of diabetes gives to RA an unfavourable prognosis. Among bone conditions, osteopenia and osteoporosis may occur early in type 1 diabetes. Contrarily, in type 2 diabetes, bone mineral density is similar or, sometimes, higher than in non diabetic subjects, probably due to hyperinsulinemia.

  2. Extracardiac manifestations of bacterial endocarditis.

    Science.gov (United States)

    Heffner, J E

    1979-08-01

    Bacterial endocarditis is an elusive disease that challenges clinicians' diagnostic capabilities. Because it can present with various combinations of extravalvular signs and symptoms, the underlying primary disease can go unnoticed.A review of the various extracardiac manifestations of bacterial endocarditis suggests three main patterns by which the valvular infection can be obscured. (1) A major clinical event may be so dramatic that subtle evidence of endocarditis is overlooked. The rupture of a mycotic aneurysm may simulate a subarachnoid hemorrhage from a congenital aneurysm. (2) The symptoms of bacterial endocarditis may be constitutional complaints easily attributable to a routine, trivial illness. Symptoms of low-grade fever, myalgias, back pain and anorexia may mimic a viral syndrome. (3) Endocarditis poses a difficult diagnostic dilemma when it generates constellations of findings that are classic for other disorders. Complaints of arthritis and arthralgias accompanied by hematuria and antinuclear antibody may suggest systemic lupus erythematosus; a renal biopsy study showing diffuse proliferative glomerulonephritis may support this diagnosis. The combination of fever, petechiae, altered mental status, thrombocytopenia, azotemia and anemia may promote the diagnosis of thrombotic thrombocytopenic purpura. When the protean guises of bacterial endocarditis create these clinical difficulties, errors in diagnosis occur and appropriate therapy is delayed. Keen awareness of the varied disease presentations will improve success in managing endocarditis by fostering rapid diagnosis and prompt therapy.

  3. Unusual florid skeletal manifestations of primary hyperparathyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Ashebu, Samuel D.; Dahniya, Mohamed H.; Muhtaseb, Sayeed A.; Aduh, Prosper [Department of Radiology, Al-Adan Hospital (Kuwait)

    2002-12-01

    We report a case of primary hyperparathyroidism (PHPT) with advanced and unusual skeletal manifestations - a rare occurrence in developed countries nowadays. The literature is briefly reviewed. (orig.)

  4. Extrahepatic manifestations of hepatitis E virus.

    Science.gov (United States)

    Kamar, Nassim; Marion, Olivier; Abravanel, Florence; Izopet, Jacques; Dalton, Harry R

    2016-04-01

    Hepatitis E virus can cause acute, fulminant and chronic hepatitis and has been associated with a range of extrahepatic manifestations. Guillain-Barré syndrome, neuralgic amyotrophy and encephalitis are the main neurological manifestations associated with acute and chronic hepatitis E virus infection. Renal injuries have been also reported, including membranoproliferative glomerulonephritis with or without cryoglobulinemia and membranous glomerulonephritis. Acute pancreatitis, haematological disorders and other autoimmune extrahepatic manifestations of hepatitis E virus, such as myocarditis and thyroiditis, have been also reported. In this comprehensive article, we review all published reports describing hepatitis E virus-associated extrahepatic manifestations.

  5. Fibre structure of decametric type II radio bursts as a manifestation of emission propagation effects in a disturbed near-solar plasma

    Directory of Open Access Journals (Sweden)

    A. N. Afanasiev

    2009-10-01

    Full Text Available This paper addresses the fine structure of solar decametric type II radio bursts in the form of drifting narrowband fibres on the dynamic spectrum. Observations show that this structure appears in those events where there is a coronal mass ejection (CME traveling in the near-solar space ahead of the shock wave responsible for the radio burst. The diversity in observed morphology of fibres and values of their parameters implies that the fibres may be caused by different formation mechanisms. The burst emission propagates through extremely inhomogeneous plasma of the CME, so one possible mechanism can be related to radio propagation effects. I suggest that the fibres in some events represent traces of radio emission caustics, which are formed due to regular refraction of radio waves on the large-scale inhomogeneous structure of the CME front. To support this hypothesis, I have modeled the propagation of radio waves through inhomogeneous plasma of the CME, taking into consideration the presence of electron density fluctuations in it. The calculations, which are based on the Monte Carlo technique, indicate that, in particular, the emission of the fibres should be harmonic. Moreover, the mechanism under consideration suggests that in solar observations from two different points in space, the observed sets of fibres can be shifted in frequency with respect to one another or can have a different structure. This potentially can be used for identifying fibres caused by the propagation effects.

  6. Skin manifestations of chronic kidney disease.

    Science.gov (United States)

    Robles-Mendez, J C; Vazquez-Martinez, O; Ocampo-Candiani, J

    2015-10-01

    Skin manifestations associated with chronic kidney disease are very common. Most of these conditions present in the end stages and may affect the patient's quality of life. Knowledge of these entities can contribute to establishing an accurate diagnosis and prognosis. Severe renal pruritus is associated with increased mortality and a poor prognosis. Nail exploration can provide clues about albumin and urea levels. Nephrogenic systemic fibrosis is a preventable disease associated with gadolinium contrast. Comorbidities, such as diabetes mellitus and secondary hyperparathyroidism, can lead to acquired perforating dermatosis and calciphylaxis, respectively. Effective and innovative treatments are available for all of these conditions. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

  7. Quantum size effects in layered VX{sub 2} (X = S, Se) materials: Manifestation of metal to semimetal or semiconductor transition

    Energy Technology Data Exchange (ETDEWEB)

    Wasey, A. H. M. Abdul; Chakrabarty, Soubhik; Das, G. P., E-mail: msgpd@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India)

    2015-02-14

    Most of the two dimensional (2D) transition metal dichalcogenides (TMDC) are nonmagnetic in pristine form. However, 2D pristine VX{sub 2} (X = S, Se, Te) materials are found to be ferromagnetic. Using spin polarized density functional theory (DFT) calculations, we have studied the electronic, magnetic, and surface properties of this class of materials in both trigonal prismatic H- and octahedral T-phase. Our calculations reveal that they exhibit materially different properties in those two polymorphs. Most importantly, detailed investigation of electronic structure explored the quantum size effect in H-phase of these materials thereby leading to metal to semimetal (H-VS{sub 2}) or semiconductor (H-VSe{sub 2}) transition when downsizing from bilayer to corresponding monolayer.

  8. Electrocardiographic Manifestations of Benzodiazepine Toxicity

    Directory of Open Access Journals (Sweden)

    Nahid Kazemzadeh

    2014-11-01

    Full Text Available Background: The aim of this study was to evaluate and compare the clinical and electrocardiographic (ECG manifestations of benzodiazepines (BZs. Methods: In this retrospective study, all BZ-poisoned patients hospitalized at Loghman Hakim Hospital between September 2010 and March 2011 were evaluated. Patients’ information including age, sex, time elapsed between the ingestion and presentation, and type of the BZ used were extracted from the patients' charts and recorded. ECGs on presentation to the emergency department (ED were evaluated and parameters such as PR interval, QRS duration, corrected QT, amplitude of S wave in lead I, height of R wave and R/S ratio in the lead aVR were also measured and recorded. Results: Oxazepam, chlordiazepoxide, lorazepam, alprazolam, diazepam, and clonazepam were ingested by 9 (3%, 13 (4.4%, 29 (9.9%, 105 (35.8%, 65 (22.2%, and 72 (24.6% patients, respectively. Mean PR interval was reported to be 0.16 ± 0.03 sec and PR interval of greater than 200 msec was detected in 12 (4.5% patients. Mean QRS duration was 0.07 ± 0.01sec and QRS≥120 msec was observed in 7 (2.6% cases. Conclusion: Diazepam is the only BZ that does not cause QRS widening and oxazepam is the only one not causing PR prolongation. It can be concluded that if a patient refers with a decreased level of consciousness and accompanying signs of BZ toxicity, QRS widening in ECG rules out diazepam, whereas PR prolongation rules out oxazepam toxicity.

  9. Gastrointestinal manifestations in cystic fibrosis.

    Science.gov (United States)

    Eggermont, E

    1996-08-01

    CFTR, or cystic fibrosis transmembrane conductance regulator, the gene product that is defective in cystic fibrosis, is present in the apical membrane of the epithelial cells from the stomach to the colon. In the foregut, the clinical manifestations are not directly related to the primary defect of the CFTR chloride channel. The most troublesome complaints and symptoms originate from the oesophagus as peptic oesophagitis or oesophageal varices. In the small intestinal wall, the clinical expression of CF depends largely on the decreased secretion of fluid and chloride ions, the increased permeability of the paracellular space between adjacent enterocytes and the sticky mucous cover over the enterocytes. As a rule, the brush border enzyme activities are normal and there is some enhanced active transport as shown for glucose and alanine. The results of continuous enteral feeding of CF patients clearly show that the small intestinal mucosa, in the daily situation, is not functioning at maximal capacity. Although CFTR expression in the colon is lower, the large intestine may be the site of several serious complications such as rectal prolapse, meconium ileus equivalent, intussusception, volvulus and silent appendicitis. In recent years colonic strictures, after the use of high-dose pancreatic enzymes, are being increasingly reported; the condition has recently been called CF fibrosing colonopathy. The CF gastrointestinal content itself differs mainly from the normal condition by the lower acidity in the foregut and the accretion of mucins and proteins, eventually resulting in intestinal obstruction, in the ileum and colon. Better understanding of the CF gastrointestinal phenotype may contribute to improvement of the overall wellbeing of these patients.

  10. Endocrine manifestations of celiac disease

    Directory of Open Access Journals (Sweden)

    R Philip

    2012-01-01

    Full Text Available Background: Celiac disease can have extra gastrointestinal tract (GIT presentations, most of which are endocrine. The aim of this study was to present patients diagnosed to have celiac disease from an endocrine department and to study the prevalence of endocrinopathies in celiac disease. Materials and Methods: A total of 36 patients from the endocrinology department (LLRM Medical College, Meerut between January 2011 and July 2012 and who were diagnosed to have celiac disease were included in the study. Results: Short stature was the commonest presentation (25%, other presentations included short stature and delayed puberty (20%, delayed puberty (11%, screening for celiac disease in type-1 DM patients (17%, rickets (6%, anemia not responding to oral therapy (6%, type-1 DM with recurrent hypoglycaemia (6%, and osteomalacia (3%. The endocrine manifestations include (after complete evaluation short stature (58%, delayed puberty (31%, elevated alkaline phospahatase (67%, low calcium (22%, X-rays suggestive of osteomalacia or rickets (8%, capopedal spasm (6%, and night blindness (6%. Anti-TPO antibody positivity was found in 53%, hypothyroidism in 28%, subclinical hypothyroidism in 17%, and type-1 DM in 25% of the patients. A total of 14% patients had no GI symptoms. Conclusion: Celiac disease is an endocrine disrupter as well as the great masquerader having varied presentations including short stature, delayed puberty, and rickets. Some patients who have celiac disease may not have any GI symptoms, making the diagnosis all the more difficult. Also, there is significant incidence of celiac disease with hypothyroidism and type-1 DM, making screening for it important in these diseases.

  11. Cystic thymic diseases: CT manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Song, Soon Young; Choi, Yo Won; Jeon, Eui Yong; Jeon, Seok Chol; Seo, Heung Suk; Hahm, Chang Kok [School of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1995-09-15

    To describe CT findings and differential points of cystic thymic lesions. We evaluated retrospectively total 19 masses with well marginated cystic lesions at thymic area on CT scans. They were 10 teratomas, 3 congenital thymic cysts, 2 multilocular thymic cysts(associated with thymoma and myasthenia gravis in each), 2 cysts Assciated with thymic Hodgkin's lymphomas an ectopic parathyroid cyst, and an infected thymic cyst. The radiological abnormalities evaluated were thickness of the wall, presence or abscene of septa, mural nodule, solid component, calcification and fat component. All three cases of congenital thymic cysts and an ectopic parathyroid cyst appeared as thin-walled unilocular cyst with homogeneous internal density and without identifiable solid component. In multilocular thymic cyst, there were thick wall and solid components(n =2), thick internal septa and calcifications(n = 1). The cysts of teratomas manifested thick walls(n = 9), internal septa(n = 4), calcifications(n = 6), fat components(n = 4), and solid components(n = 4). Cysts in Hodgkin's diseases appeared as multilocular or unilocular and had thick wall and septa without calcification. Infected thymic cyst presented with multilocular cystic mass with identifiable wall and septa, calcification, and solid components. The thymic diseases with cystic lesion include teratomas, congenital thymic cysts, multilocular thymic cysts, parathyroid cyst, and Hodgkin's disease. Congenital thymic cyst and ectopic parathyroid cyst are thin-walled unilocular cystic lesions. Cystic lesions associated with teratoma, Hodgkin's disease, and multilocular thymic cyst are thick-walled cystic lesions with or without solid component.

  12. Clinical manifestation of myeloperoxidase deficiency.

    Science.gov (United States)

    Lanza, F

    1998-09-01

    Myeloperoxidase (MPO), an iron-containing heme protein localized in the azurophilic granules of neutrophil granulocytes and in the lysosomes of monocytes, is involved in the killing of several micro-organisms and foreign cells, including bacteria, fungi, viruses, red cells, and malignant and nonmalignant nucleated cells. Despite the primary role of the oxygen-dependent MPO system in the destruction of certain phagocytosed microbes, subjects with total or partial MPO deficiency generally do not have an increased frequency of infections, probably because other MPO-independent mechanism(s) for microbicidal activity compensate for the lack of MPO. Infectious diseases, especially with species of Candida, have been observed predominantly in MPO-deficient patients who also have diabetes mellitus, but the frequency of such cases is very low, less than 5% of reported MPO-deficient subjects. Evidence from a number of investigators indicates that individuals with total MPO deficiency show a high incidence of malignant tumors. Since MPO-deficient PMNs exhibit in vitro a depressed lytic action against malignant human cells, it can be speculated that the neutrophil MPO system plays a central role in the tumor surveillance of the host. However, any definitive conclusion on the association between MPO deficiency and the occurrence of cancers needs to be confirmed in further clinical studies. Clinical manifestations of this disorder depend on the nature of the defect; an acquired abnormality associated with other hematological or nonhematological diseases has been occasionally described, but the primary deficiency is the form more commonly reported. Another area of interest pertinent to MPO expression is related to the use of anti-MPO monoclonal antibodies for the lineage assignment of acute leukemic cells, the definition of FAB MO acute myeloid leukemia, the identification of biphenotypic acute leukemias, and their distinction from acute leukemia with minimal phenotypic deviation

  13. The Effect of Recombinant Granulocyte Colony-Stimulating Factor on Oral and Periodontal Manifestations in a Patient with Cyclic Neutropenia: A Case Report

    Directory of Open Access Journals (Sweden)

    Sergio Matarasso

    2009-01-01

    Full Text Available Cyclic Neutropenia (CN is characterized by recurrent infections, fever, oral ulcerations, and severe periodontitis as result of the reduced host defences. The previous studies have established the effectiveness of recombinant granulocyte colony-stimulating factor (GCSF to increase the number and the function of neutrophils in the peripheral blood in this disease. In a 20-year-old Caucasian female with a diagnosis of cyclic neutropenia, oral clinical examination revealed multiple painful ulcerations of the oral mucosa, poor oral hygiene conditions, marginal gingivitis, and moderate periodontitis. The patient received a treatment with G-CSF (Pegfilgrastim, 6 mg/month in order to improve her immunological status. Once a month nonsurgical periodontal treatment was carefully performed when absolute neutrophil count (ANC was ≥500/L. The treatment with G-CSF resulted in a rapid increase of circulating neutrophils that, despite its short duration, leaded to a reduction in infection related events and the resolution of the multiple oral ulcerations. The disappearance of oral pain allowed an efficacy nonsurgical treatment and a normal tooth brushing that determined a reduction of probing depth (PD≤4 mm and an improvement of the oral hygiene conditions recorded at 6-month follow-up.

  14. The Effect of a Novel c.820C>T (Arg274Trp) Mutation in the Mitofusin 2 Gene on Fibroblast Metabolism and Clinical Manifestation in a Patient

    Science.gov (United States)

    Kawalec, Maria; Kabzińska, Dagmara; Kochański, Andrzej; Krzyśko, Krystiana A.; Zabłocka, Barbara

    2017-01-01

    Charcot-Marie-Tooth disease type 2A (CMT2A) is an autosomal dominant axonal peripheral neuropathy caused by mutations in the mitofusin 2 gene (MFN2). Mitofusin 2 is a GTPase protein present in the outer mitochondrial membrane and responsible for regulation of mitochondrial network architecture via the fusion of mitochondria. As that fusion process is known to be strongly dependent on the GTPase activity of mitofusin 2, it is postulated that the MFN2 mutation within the GTPase domain may lead to impaired GTPase activity, and in turn to mitochondrial dysfunction. The work described here has therefore sought to verify the effects of MFN2 mutation within its GTPase domain on mitochondrial and endoplasmic reticulum morphology, as well as the mtDNA content in a cultured primary fibroblast obtained from a CMT2A patient harboring a de novo Arg274Trp mutation. In fact, all the parameters studied were affected significantly by the presence of the mutant MFN2 protein. However, using the stable model for mitofusin 2 obtained by us, we were next able to determine that the Arg274Trp mutation does not impact directly upon GTP binding. Such results were also confirmed for GTP-hydrolysis activity of MFN2 protein in patient fibroblast. We therefore suggest that the biological malfunctions observable with the disease are not consequences of impaired GTPase activity, but rather reflect an impaired contribution of the GTPase domain to other MFN2 activities involving that region, for example protein-protein interactions. PMID:28076385

  15. Effects of alien and intraspecies cytoplasms on manifestation of nuclear genes for wheat resistance to brown rust: II. Specificity of cytoplasm influence on different Lr genes

    Energy Technology Data Exchange (ETDEWEB)

    Voluevich, E.A.; Buloichik, A.A.; Palilova, A.N. [Institute of Genetics and Cytology, Minsk (Belarus)

    1995-04-01

    Specificity of expression of the major nuclear genes Lr to two brown rust clones in hybrids with the same maternal cytoplasm was analyzed. It was evaluated by a resistant: susceptible ratio in the F{sub 2}. Reciprocal hybrids were obtained from the cross between the progeny of homozygous susceptible plants of the cultivar Penjamo 62 and its alloplasmatic lines carrying cytoplasms of Triticum dicoccoides var. fulvovillosum, Aegilops squarrosa var. typical, Agropyron trichophorum, and isogenic lines of the cultivar Thatcher (Th) with the Lr1, Lr9, Lr15, and Lr19 genes. It was shown that the effect of the Lr1 gene in the cytoplasm of cultivar Thatcher and in eu-, and alloplasmatic forms of Penjamo 62 was less expressed than that of other Lr genes. Cytoplasm of the alloplasmatic line (dicoccoides)-Penjamo 62 was the only exception: in the F{sub 2}, hybrids with Th (Lr1) had a higher yield of resistant forms than those with Th (Lr15). In the hybrid combinations studied, expression and/or transmission of the Lr19 gene was more significant than that of other genes. This gene had no advantages over Lr15 and Lr19 only in cytoplasm of the alloplasmatic line (squarrosa)-Penjamo 62. In certain hybrid cytoplasms, the display of the Lr1, Lr15, and Lr19 genes, in contrast to Lr9, varied with the virulence of the pathogen clones. 15 refs., 5 tabs.

  16. Sesamin manifests chemopreventive effects through the suppression of NF-kappa B-regulated cell survival, proliferation, invasion, and angiogenic gene products.

    Science.gov (United States)

    Harikumar, Kuzhuvelil B; Sung, Bokyung; Tharakan, Sheeja T; Pandey, Manoj K; Joy, Beena; Guha, Sushovan; Krishnan, Sunil; Aggarwal, Bharat B

    2010-05-01

    Agents that are safe, affordable, and efficacious are urgently needed for the prevention of chronic diseases such as cancer. Sesamin, a lipid-soluble lignan, is one such agent that belongs to a class of phytoestrogens, isolated from sesame (Sesamum indicum), and has been linked with prevention of hyperlipidemia, hypertension, and carcinogenesis through an unknown mechanism. Because the transcription factor NF-kappaB has been associated with inflammation, carcinogenesis, tumor cell survival, proliferation, invasion, and angiogenesis of cancer, we postulated that sesamin might mediate its effect through the modulation of the NF-kappaB pathway. We found that sesamin inhibited the proliferation of a wide variety of tumor cells including leukemia, multiple myeloma, and cancers of the colon, prostate, breast, pancreas, and lung. Sesamin also potentiated tumor necrosis factor-alpha-induced apoptosis and this correlated with the suppression of gene products linked to cell survival (e.g., Bcl-2 and survivin), proliferation (e.g., cyclin D1), inflammation (e.g., cyclooxygenase-2), invasion (e.g., matrix metalloproteinase-9, intercellular adhesion molecule 1), and angiogenesis (e.g., vascular endothelial growth factor). Sesamin downregulated constitutive and inducible NF-kappaB activation induced by various inflammatory stimuli and carcinogens, and inhibited the degradation of IkappaBalpha, the inhibitor of NF-kappaB, through the suppression of phosphorylation of IkappaBalpha and inhibition of activation of IkappaBalpha protein kinase, thus resulting in the suppression of p65 phosphorylation and nuclear translocation, and NF-kappaB-mediated reporter gene transcription. The inhibition of IkappaBalpha protein kinase activation was found to be mediated through the inhibition of TAK1 kinase. Overall, our results showed that sesamin may have potential against cancer and other chronic diseases through the suppression of a pathway linked to the NF-kappaB signaling.

  17. Thermal effects on photon-induced quantum transport in a single quantum dot.

    Science.gov (United States)

    Assunção, M O; de Oliveira, E J R; Villas-Bôas, J M; Souza, F M

    2013-04-03

    We theoretically investigate laser induced quantum transport in a single quantum dot attached to electrical contacts. Our approach, based on a nonequilibrium Green function technique, allows us to include thermal effects on the photon-induced quantum transport and excitonic dynamics, enabling the study of non-Markovian effects. By solving a set of coupled integrodifferential equations, involving correlation and propagator functions, we obtain the photocurrent and the dot occupation as a function of time. Two distinct sources of decoherence, namely, incoherent tunneling and thermal fluctuations, are observed in the Rabi oscillations. As temperature increases, a thermally activated Pauli blockade results in a suppression of these oscillations. Additionally, the interplay between photon and thermally induced electron populations results in a switch of the current sign as time evolves and its stationary value can be maximized by tuning the laser intensity.

  18. Manifestation of peripherial coding in the effect of increasing loudness and enhanced discrimination of the intensity of tone bursts before and after tone burst noise

    Science.gov (United States)

    Rimskaya-Korsavkova, L. K.

    2017-07-01

    maxima and the ratio between them. The size of the first maximum in the of interspike interval distribution could be the basis for the formation of the loudness of the masked tone burst (implicit loudness), and the size of the second maximum, for the formation of intensity in the periodicity pitch of the complex. The auditory effect of the midlevel enhancement of tone burst loudness could be the result of variations in the implicit tone burst loudness caused by variations in tone-burst or noise intensity. The reason for the enhancement of the Weber fraction could be competitive interaction between such subjective qualities as explicit and implicit tone-burst loudness and the intensity of the periodicity pitch of the complex.

  19. Clinical manifestations and managements in jellyfish envenomation A systematic review

    Directory of Open Access Journals (Sweden)

    Negar Taheri

    2013-11-01

    Full Text Available Background: The phylum Cnidarians have over nine thousand species that approximately, one hundred species are dangerous for humans. Annually, a large number of deaths were reported due to jellyfish stings. The manifestations depend on their species and kind of venoms, and include the local and systemic manifestations. A number of methods and compounds were used and under investigation for management of injuries with jellyfishes. Due to the lack of an integrated systematic review, the current study was done. Materials and Methods: The PubMed data bank was searched for the term “Jellyfish”. A total of 1677 papers were found. These papers were divided into three categories: medical, biomedical and biotechnological fields. The medical category was further divided into three subcategories comprising systemic manifestations, cutaneous manifestations and treatments for the stings of jellyfishes. The biomedical category was further subdivided into genomics, proteomics, and biology of venoms, mechanisms of actions and products of biomedical significance. In this part of systematic review, the medical aspects of injuries with jellyfishes were evaluated. Results: The clinical manifestations in jellyfish envenomation depend on their species and the nature of venoms. The most common clinical manifestations of jellyfish stings are cutaneous presentations like urticasia, erythema, swelling, vesicles and severe dermonectoric manifestations. Systemic manifestations were seen in the stings of box jellyfishes, Portuguese man-of-war and in Irukandji syndrome. The most common recommendations for jellyfish envenomation managements include decreasing the local effects of venom, prevention of the venomous nematocysts release, and Controlling of systemic reactions. Application of commercial vinegar (4 - 6% acetic acid, hot water immersion (HWI (42 ° C for 20 minutes, ice packs, sea water rinsing for inactivating nematocysts, administration of topical and parenteral

  20. [Hemolytic uremic syndrome. Clinical manifestations. Treatment].

    Science.gov (United States)

    Exeni, Ramón A

    2006-01-01

    Clinical manifestation are described in children with epidemic HUS. The intestinal involvement in the prodromic period, is outlined and the most common disturbances such acute renal failure, thrombocytopenia, hemolytic anemia, leucocitosis hypertension, neurological, pancreatic and cardiac manifestations are described. We discuss the acid-base and electrolyte disturbances, metabolic acidosis, hyponatremia, hyperkalemia. The etiopathogenic treatment and the control of renal sequelae are also discussed.

  1. Oral manifestations of syphilis: a review

    Directory of Open Access Journals (Sweden)

    A.B. Soares

    2004-01-01

    Full Text Available Syphilis is an infectious disease presenting stages associated with specific oral lesions. Therefore, health professionals should be familiar with the different syphilis oral manifestations at each stage and be prepared to refer any suspected patient for further evaluation. This report describes the most important clinical factors of each stage, emphasizing the oral manifestations.

  2. Cardiac manifestations of inborn errors of metabolism.

    NARCIS (Netherlands)

    Evangeliou, A.; Papadopoulou-Legbelou, K.; Daphnis, E.; Ganotakis, E.; Vavouranakis, I.; Michailidou, H.; Hitoglou-Makedou, A.; Nicolaidou, P.; Wevers, R.A.; Varlamis, G.

    2007-01-01

    AIM: The aim of the study was to investigate the frequency and type of cardiac manifestations in a defined group of patients with inborn errors of metabolism. This paper also explores the key role of cardiac manifestations in the diagnosis of inborn errors of metabolism in daily practice. METHODS: O

  3. Pulmonary manifestations of the antiphospholipid antibody syndrome.

    Science.gov (United States)

    Ford, H James; Roubey, Robert A S

    2010-09-01

    A broad spectrum of pulmonary disease may occur in antiphospholipid antibody syndrome. The most common pulmonary manifestations are pulmonary thromboembolism and pulmonary hypertension. In this article the authors review these manifestations, as well as less common findings including acute respiratory distress syndrome, alveolar hemorrhage, and pulmonary capillaritis.

  4. Congenital rubella syndrome and delayed manifestations

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2010-01-01

    Objective: Several hypotheses of different medical and psychological delayed manifestations among people who have congenital rubella syndrome (CRS) have been discussed. This study tests some of these hypotheses of delayed manifestations. Methods: Gathering information about 35 individuals who hav...... which people with CRS face must primarily be understood in relation to congenital deafblindness and dual sensory and communicative deprivation....

  5. 21 CFR 11.50 - Signature manifestations.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Signature manifestations. 11.50 Section 11.50 Food... RECORDS; ELECTRONIC SIGNATURES Electronic Records § 11.50 Signature manifestations. (a) Signed electronic...: (1) The printed name of the signer; (2) The date and time when the signature was executed; and...

  6. Effect of two-qutrit entanglement on quantum speed limit time of a bipartite V-type open system

    Energy Technology Data Exchange (ETDEWEB)

    Behzadi, N., E-mail: n.behzadi@tabrizu.ac.ir [Research Institute for Fundamental Sciences, University of Tabriz (Iran, Islamic Republic of); Ahansaz, B.; Ektesabi, A.; Faizi, E. [Physics Department, Azarbaijan Shahid Madani University, Tabriz (Iran, Islamic Republic of)

    2017-03-15

    In the present paper, quantum speed limit (QSL) time of a bipartite V-type three-level atomic system under the effect of two-qutrit entanglement is investigated. Each party interacts with own independent reservoir. By considering two local unitarily equivalent Werner states and the Horodecki PPT state, as initial states, the QSL time is evaluated for each of them in the respective entangled regions. It is counterintuitively observed that the effect of entanglement on the QSL time driven from each of the initial Werner states are completely different when the degree of non-Markovianity is considerable. In addition, it is interesting that the effect of entanglement of the non-equivalent Horodecki state on the calculated QSL time displays an intermediate behavior relative to the cases obtained for the Werner states.

  7. Extraintestinal manifestations and complications in inflammatory bowel diseases

    Institute of Scientific and Technical Information of China (English)

    Katja S Rothfuss; Eduard F Stange; Klaus R Herrlinger

    2006-01-01

    Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory bowel diseases (IBD) that often involve organs other than those of the gastrointestinal tract. These nonintestinal affections are termed extraintestinal symptoms. Differentiating the true extraintestinal manifestations of inflammatory bowel diseases from secondary extraintestinal complications, caused by malnutrition, chronic inflammation or side effects of therapy, may be difficult. This review concentrates on frequency, clinical presentation and therapeutic implications of extraintestinal symptoms in inflammatory bowel diseases. If possible, extraintestinal manifestations are differentiated from extraintestinal complications. Special attention is given to the more recently described sites of involvement; I.e. Thromboembolic events, osteoporosis, pulmonary involvement and affection of the central nervous system.

  8. Weight loss and skin manifestations in obese patients with psoriasis

    DEFF Research Database (Denmark)

    Geiker, Nina Rica Wium; Jensen, Peter; Kirchner Larsson, Lena

    2010-01-01

    % of their body weight following calorie restriction for 12 weeks. Taken together with recent literature the findings suggest that weight loss has a potential to reduce skin manifestations. Weight loss might also attenuate the increased cardiovascular and diabetes risks posed by obese psoriatric patients.......Objective To examine if psoriatic patients can achieve a weight loss to the same extent as non-psoriatic patients To describe the effect of weight loss on the cutaneous manifestations. Conclusion Patients with psoriasis achieved a weight loss, similar to non-psoriatic patients, of 12...

  9. The Spectrum of Neurological Manifestations Associated with Gaucher Disease

    Directory of Open Access Journals (Sweden)

    Tamanna Roshan Lal

    2017-03-01

    Full Text Available Gaucher disease, the most common lysosomal storage disorder, is due to a deficiency in the enzyme glucocerebrosidase. This leads to the accumulation of its normal substrate, glucocerebroside, in tissue macrophages, affecting the hematological, visceral, bone and neurologic systems. Gaucher disease is classified into three broad phenotypes based upon the presence or absence of neurological involvement: type 1 (non-neuronopathic, type 2 (acute neuronopathic, and type 3 (subacute neuronopathic. Phenotypically, there is a wide spectrum of visceral and neurological manifestations. Enzyme replacement is effective in managing the visceral disease; however, treating the neurological manifestations has proved to be more challenging. This review discusses the various neurological manifestations encountered in Gaucher disease, and provides a brief overview regarding the treatment and ongoing research challenges.

  10. Manifestations of chronic hepatitis C virus infection beyond the liver.

    Science.gov (United States)

    Jacobson, Ira M; Cacoub, Patrice; Dal Maso, Luigino; Harrison, Stephen A; Younossi, Zobair M

    2010-12-01

    In addition to its effects in the liver, chronic hepatitis C virus (HCV) infection can have serious consequences for other organ systems. Extrahepatic manifestations include mixed cryoglobulinemia (MC) vasculitis, lymphoproliferative disorders, renal disease, insulin resistance, type 2 diabetes, sicca syndrome, rheumatoid arthritis-like polyarthritis, and autoantibody production; reductions in quality of life involve fatigue, depression, and cognitive impairment. MC vasculitis, certain types of lymphoma, insulin resistance, and cognitive function appear to respond to anti-HCV therapy. However, treatments for HCV and other biopsychosocial factors can reduce quality of life and complicate management. HCV treatment has a high overall cost that increases when extrahepatic manifestations are considered. HCV appears to have a role in the pathogenesis of MC vasculitis, certain types of lymphoma, and insulin resistance. Clinicians who treat patients with HCV infections should be aware of potential extrahepatic manifestations and how these can impact and alter management of their patients.

  11. [Extrahepatic manifestations of infection with hepatitis C virus].

    Science.gov (United States)

    García Ferrera, Waldo O; Nodarse Cuní, Hugo; Moredo Romo, Edelisa

    2009-01-01

    Since the identification of hepatitis C in 1989, it has been studied extensively. In addition to its hepatotropic; have extrahepatic effects that are directly related to extrahepatic replication with high affinity to lymphoid tissues. As a result of that characteristics, autoimmune manifestations or a widespread immune stimulation, hematological, endocrine, dermatological, Ophtalmic, salival and other miscellaneous problems can be presented in affected patients.

  12. Quantum effects with an x-ray free-electron laser.

    Science.gov (United States)

    Roberts, C D; Schmidt, S M; Vinnik, D V

    2002-10-07

    A quantum kinetic equation coupled with Maxwell's equation is used to estimate the laser power required at an x-ray free-electron laser (XFEL) facility to expose intrinsically quantum effects in the process of QED vacuum decay via spontaneous pair production. A 9 -TW-peak XFEL laser with photon energy of 8.3 keV could be sufficient to initiate particle accumulation and the consequent formation of a plasma of spontaneously produced pairs. The evolution of the particle number in the plasma will exhibit non-Markovian aspects of the strong-field pair production process, and the plasma's internal currents will generate an electric field whose interference with that of the laser leads to plasma oscillations.

  13. Periodontal and oral manifestations of marijuana use.

    Science.gov (United States)

    Rawal, Swati Y; Tatakis, Dimitris N; Tipton, David A

    2012-01-01

    Marijuana, prepared from the plant Cannabis sativa, is the most widely used illicit drug in the United States. Marijuana use has been associated with adverse psychosocial and health effects, including effects on oral tissues. Periodontal literature has limited references to the periodontal effects of cannabis use. In this report, we present two cases of marijuana-associated gingival enlargement and review the literature on oral complications of marijuana use. Two asymptomatic males, aged 23 and 42 years, presented independently for oral prophylaxis. Both had an unremarkable medical history and related a history of significant marijuana use of 2-16 years duration. Common findings following oral and periodontal examination were nicotinic stomatitis-like lesions, uvulitis and gingival enlargement. Marginal and papillary gingiva of the anterior dentition were the areas primarily affected by gingival enlargement, while some of these areas exhibited a nodular or "pebbly" appearance. Marijuana-associated gingival enlargement was diagnosed in the reported cases. A review of the literature revealed two other reports of marijuana-associated gingival enlargement, all in young adult males with chronic (2 or more years) cannabis use. These authors reported a resemblance to phenytoin-induced enlargement. Biochemical similarities between phenytoin and cannabis active compounds suggest possible common pathogenetic mechanisms. Uvulitis and nicotinic stomatitis appear to be the two most common of the several oral manifestations of marijuana use. Chronic marijuana use may result in gingival enlargement with clinical characteristics similar to phenytoin-induced enlargement.

  14. Neurological Manifestations In Inflammatory Bowel Disease

    Directory of Open Access Journals (Sweden)

    youssef HNACH

    2015-06-01

    Full Text Available IntroductionThe purpose of this retrospective study was to report neurological manifestations noted in patients who were monitored for inflammatory bowel disease, in order to document the pathophysiological, clinical, progressive, and therapeutic characteristics of this entity.Material and methodsWe conducted a retrospective study on patients monitored -in the gastroenterology service in Ibn Sina Hospital in Rabat, Morocco- for inflammatory bowel disease from 1992 till 2013 and who developed neurological manifestations during its course. Patients with iatrogenic complications were excluded, as well as patients with cerebrovascular risk factors.ResultsThere were 6 patients, 4 of whom have developed peripheral manifestations. Electromyography enabled the diagnosis to be made and the outcome was favorable with disappearance of clinical manifestations and normalization of the electromyography.The other 2 patients, monitored for Crohn’s disease, developed ischemic stroke. Cerebral computed tomography angiography provided positive and topographic diagnosis. Two patients were admitted to specialized facilities.ConclusionNeurological manifestations in inflammatory bowel disease are rarely reported.  Peripheral neuropathies and stroke remain the most common manifestations. The mechanisms of these manifestations are not clearly defined yet. Currently, we hypothesize the interaction of immune mediators.

  15. [Lyme disease--clinical manifestations and treatment].

    Science.gov (United States)

    Stock, Ingo

    2016-05-01

    Lyme disease (Lyme borreliosis) is a systemic infectious disease that can present in a variety of clinical manifestations. The disease is caused by a group of spirochaetes--Borrelia burgdorferi sensu lato or Lyme borrelia--that are transmitted to humans by the bite of Ixodes ticks. Lyme disease is the most common arthropode-borne infectious disease in many European countries including Germany. Early localized infection is typically manifested by an erythema migrans skin lesion, in rarer cases as a borrelial lymphocytoma. The most common early disseminated manifestation is (early) neuroborreliosis. In adults, neuroborreliosis appears typically as meningoradiculoneuritis. Neuroborreliosis in children, however, is typically manifested by meningitis. In addition, multiple erythema migrans lesions and Lyme carditis occur relatively frequently. The most common manifestation oflate Lyme disease is Lyme arthritis. Early manifestations (and usually also late manifestations) of Lyme disease can be treated successfully by application of suitable antibacterial agents. For the treatment of Lyme disease, doxycycline, certain penicillins such as amoxicillin and some cephalosporins (ceftriaxone, cefotaxime, cefuroxime axetil) are recommended in current guidelines. A major challenge is the treatment of chronic, non-specific disorders, i. e., posttreatment Lyme disease syndrome and "chronic Lyme disease". Prevention of Lyme disease is mainly accomplished by protecting against tick bites. Prophylactic administration of doxycycline after tick bites is generally not recommended in Germany. There is no vaccine available for human beings.

  16. Genetic alterations in syndromes with oral manifestations.

    Science.gov (United States)

    Anuthama, Krishnamurthy; Prasad, Harikrishnan; Ramani, Pratibha; Premkumar, Priya; Natesan, Anuja; Sherlin, Herald J

    2013-11-01

    Ever since Gregor Johan Mendel proposed the law of inheritance, genetics has transcended the field of health and has entered all walks of life in its application. Thus, the gene is the pivoting factor for all happenings revolving around it. Knowledge of gene mapping in various diseases would be a valuable tool in prenatally diagnosing the condition and averting the future disability and stigma for the posterity. This article includes an array of genetically determined conditions in patients seen at our college out-patient department with complete manifestation, partial manifestation and array of manifestations not fitting into a particular syndrome.

  17. Genetic alterations in syndromes with oral manifestations

    Directory of Open Access Journals (Sweden)

    Krishnamurthy Anuthama

    2013-01-01

    Full Text Available Ever since Gregor Johan Mendel proposed the law of inheritance, genetics has transcended the field of health and has entered all walks of life in its application. Thus, the gene is the pivoting factor for all happenings revolving around it. Knowledge of gene mapping in various diseases would be a valuable tool in prenatally diagnosing the condition and averting the future disability and stigma for the posterity. This article includes an array of genetically determined conditions in patients seen at our college out-patient department with complete manifestation, partial manifestation and array of manifestations not fitting into a particular syndrome.

  18. Biological therapy for dermatological manifestations of inflammatory bowel disease.

    Science.gov (United States)

    Zippi, Maddalena; Pica, Roberta; De Nitto, Daniela; Paoluzi, Paolo

    2013-05-16

    Ulcerative colitis and Crohn's disease are the two forms of inflammatory bowel disease (IBD). The advent of biological drugs has significantly changed the management of these conditions. Skin manifestations are not uncommon in IBD. Among the reactive lesions (immune-mediated extraintestinal manifestations), erythema nodosum (EN) and pyoderma gangrenosum (PG) are the two major cutaneous ills associated with IBD, while psoriasis is the dermatological comorbidity disease observed more often. In particular, in the last few years, anti-tumor necrosis factor (TNF)-α agents have been successfully used to treat psoriasis, especially these kinds of lesions that may occur during the treatment with biological therapies. The entity of the paradoxical manifestations has been relatively under reported as most lesions are limited and a causal relationship with the treatment is often poorly understood. The reason for this apparent side-effect of the therapy still remains unclear. Although side effects may occur, their clinical benefits are undoubted. This article reviews the therapeutic effects of the two most widely used anti-TNF-α molecules, infliximab (a fusion protein dimer of the human TNF-α receptor) and adalimumab (a fully human monoclonal antibody to TNF-α), for the treatment of the major cutaneous manifestations associated with IBD (EN, PG and psoriasis).

  19. Dermatologic manifestations of polycystic ovary syndrome.

    Science.gov (United States)

    Lee, Amy T; Zane, Lee T

    2007-01-01

    Polycystic ovary syndrome (PCOS) affects 5-10% of reproductive-aged women and is one of the most common endocrine disorders in women. The disorder is commonly characterized by elevated levels of androgen and insulin. Women with PCOS may present with a range of signs and symptoms, and face increased risks of reproductive, metabolic, cardiovascular, psychologic, and neoplastic sequelae, particularly if the condition is left unrecognized or untreated. The clinical definition of PCOS has changed in recent years and includes as one of its cardinal criteria the dermatologic manifestations of hyperandrogenism, chiefly hirsutism, acne vulgaris, and androgenetic alopecia. Acanthosis nigricans, a cutaneous sign of hyperinsulinemia, may also be present. These dermatologic features may provide early clinical clues to recognition of PCOS, and treatment of these cutaneous conditions may improve the patient's quality of life and psychologic well-being. The effects of androgen on pilosebaceous units in the skin can vary by anatomic location, producing pathophysiologic effects on hair growth and differentiation, sebaceous gland size and activity, and follicular keratinization. Treatment modalities may include hormonal therapy intended to modulate androgen production and action as well as non-hormonal therapies directed toward specific dermatologic conditions.

  20. Endocrine disorders and the neurologic manifestations.

    Science.gov (United States)

    Yu, Jeesuk

    2014-12-01

    The nervous system and the endocrine system are closely interrelated and both involved intimately in maintaining homeostasis. Endocrine dysfunctions may lead to various neurologic manifestations such as headache, myopathy, and acute encephalopathy including coma. It is important to recognize the neurologic signs and symptoms caused by the endocrine disorders while managing endocrine disorders. This article provides an overview of the neurologic manifestations found in various endocrine disorders that affect pediatric patients. It is valuable to think about 'endocrine disorder' as a cause of the neurologic manifestations. Early diagnosis and treatment of hormonal imbalance can rapidly relieve the neurologic symptoms. Better understanding of the interaction between the endocrine system and the nervous system, combined with the knowledge about the pathophysiology of the neurologic manifestations presented in the endocrine disorders might allow earlier diagnosis and better treatment of the endocrine disorders.

  1. Manifest toob klassika taas kinoekraanile / Andri Maimets

    Index Scriptorium Estoniae

    Maimets, Andri, 1979-

    2007-01-01

    2.-9. veebr. on kinos "Sõprus" ja 11.-15. veebr. Tartu Sadamateatris 5. kultusfilmide festival Manifest, seekord USA filmid ja teemaks sõnavabadus. Esilinastub ka Urmas E. Liivi dokumentaalfilm "Tervitusi Nõukogude Eestist!"

  2. Mucocutaneous manifestations of helminth infections: Nematodes.

    Science.gov (United States)

    Lupi, Omar; Downing, Christopher; Lee, Michael; Pino, Livia; Bravo, Francisco; Giglio, Patricia; Sethi, Aisha; Klaus, Sidney; Sangueza, Omar P; Fuller, Claire; Mendoza, Natalia; Ladizinski, Barry; Woc-Colburn, Laila; Tyring, Stephen K

    2015-12-01

    In the 21st century, despite increased globalization through international travel for business, medical volunteerism, pleasure, and immigration/refugees into the United States, there is little published in the dermatology literature regarding the cutaneous manifestations of helminth infections. Approximately 17% of travelers seek medical care because of cutaneous disorders, many related to infectious etiologies. This review will focus on the cutaneous manifestations of helminth infections and is divided into 2 parts: part I focuses on nematode infections, and part II focuses on trematode and cestode infections. This review highlights the clinical manifestations, transmission, diagnosis, and treatment of helminth infections. Nematodes are roundworms that cause diseases with cutaneous manifestations, such as cutaneous larval migrans, onchocerciasis, filariasis, gnathostomiasis, loiasis, dracunculiasis, strongyloidiasis, ascariasis, streptocerciasis, dirofilariasis, and trichinosis. Tremadotes, also known as flukes, cause schistosomiasis, paragonimiasis, and fascioliasis. Cestodes (tapeworms) are flat, hermaphroditic parasites that cause diseases such as sparganosis, cysticercosis, and echinococcus.

  3. Musculoskeletal manifestations of the antiphospholipid syndrome.

    Science.gov (United States)

    Noureldine, M H A; Khamashta, M A; Merashli, M; Sabbouh, T; Hughes, G R V; Uthman, I

    2016-04-01

    The scope of clinical and laboratory manifestations of the antiphospholipid syndrome (APS) has increased dramatically since its discovery in 1983, where any organ system can be involved. Musculoskeletal complications are consistently reported in APS patients, not only causing morbidity and mortality, but also affecting their quality of life. We reviewed all English papers on APS involvement in the musculoskeletal system using Google Scholar and Pubmed; all reports are summarized in a table in this review. The spectrum of manifestations includes arthralgia/arthritis, avascular necrosis of bone, bone marrow necrosis, complex regional pain syndrome type-1, muscle infarction, non-traumatic fractures, and osteoporosis. Some of these manifestations were reported in good quality studies, some of which showed an association between aPL-positivity and the occurrence of these manifestations, while others were merely described in case reports.

  4. Cutaneous manifestations of dermatomyositis and their management.

    Science.gov (United States)

    Callen, Jeffrey P

    2010-06-01

    Dermatomyositis is a condition with pathognomonic and characteristic cutaneous lesions. This article describes the skin manifestations observed in patients with dermatomyositis, their differential diagnosis, their relationship to internal disease (particularly malignancy), and their management.

  5. Neuropsychiatric Manifestations of Parkinson`s Disease

    Directory of Open Access Journals (Sweden)

    Ana Peixinho

    2014-10-01

    Full Text Available Parkinson’s disease affects about 1% of the world population older than 65 years. It’s most frequently considered a movement disorder, but the neuropsychiatric manifestations associated with the disease and/or its treatment may be of equal or greater significance in some patients. We will discuss briefly the epidemiology, physiopathology and diagnosis of Parkinson’s disease, highlighting the neuropsychiatric manifestations: depression, anxiety, psychosis, dementia, sleep disorders, dopamine dysregulation syndrome.

  6. Hashimoto's Encephalitis: Rare Manifestation of Hypothyroidism.

    Science.gov (United States)

    Gutch, Manish; Bhattacharjee, Annesh; Kumar, Sukriti; Pushkar, Durgesh

    2017-01-01

    Hashimoto's encephalitis is a rare, heterogeneous and completely treatable form of neuroendocrine disorder manifesting with seizures, stroke-like episodes, encephalopathy, dementia and variable neuropsychiatric manifestations. It is generally associated with a background of Hashimoto's Thyroiditis, and the patient has high titers of antithyroid antibodies, especially antithyroid peroxidase antibodies. This entity responds dramatically to corticosteroids, hence should be always considered and excluded while treating a patient with encephalopathy in the background of a thyroid disease.

  7. Endocrine disorders and the neurologic manifestations

    OpenAIRE

    Yu, Jeesuk

    2014-01-01

    The nervous system and the endocrine system are closely interrelated and both involved intimately in maintaining homeostasis. Endocrine dysfunctions may lead to various neurologic manifestations such as headache, myopathy, and acute encephalopathy including coma. It is important to recognize the neurologic signs and symptoms caused by the endocrine disorders while managing endocrine disorders. This article provides an overview of the neurologic manifestations found in various endocrine disord...

  8. Clinical Manifestations and Diagnosis of Acromegaly

    OpenAIRE

    Gloria Lugo; Lara Pena; Fernando Cordido

    2012-01-01

    Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Ac...

  9. Neuropsychiatric Manifestations of Parkinson`s Disease

    OpenAIRE

    Peixinho, Ana; De Azevedo, Ana Luísa; Simões, Rita Moiron

    2006-01-01

    Parkinson’s disease affects about 1% of the world population older than 65 years. It’s most frequently considered a movement disorder, but the neuropsychiatric manifestations associated with the disease and/or its treatment may be of equal or greater significance in some patients. We will discuss briefly the epidemiology, physiopathology and diagnosis of Parkinson’s disease, highlighting the neuropsychiatric manifestations: depression, anxiety, psychosis, dementia, sleep disorders, dopamine d...

  10. [Extrahepatic manifestations of hepatitis C virus infection].

    Science.gov (United States)

    Roca, Bernardino

    2004-10-01

    Hepatitis C virus predominantly affects the liver, although it may also produce a number of extrahepatic manifestations, such as mixed cryoglobulinemia, salivary and lacrimal gland dysfunction, and several types of kidney disease. The pathogenesis of these conditions is not completely understood, but immunologic mechanisms are involved in many cases. In some patients with hepatitis C virus infection, the extrahepatic manifestations predominate and their proper diagnosis and management is very important.

  11. Neurologic Manifestations of Childhood Rheumatic Diseases

    Directory of Open Access Journals (Sweden)

    Reza SHIARI

    2012-10-01

    Full Text Available Children with rheumatic disorders may have a wide variety of clinical features ranging from fever or a simple arthritis to complex multisystem autoimmune diseases. Information about the prevalence of neurological manifestations in children with rheumatologic disorders is limited. This review describes the neurologic complications of childhood Rheumatic disease either solely or combined with symptoms of other organs involvement, as a primary manifestation or as a part of other symptoms, additionally.

  12. Current oral manifestations of HIV infection.

    Science.gov (United States)

    Navazesh, M

    2001-02-01

    The oral manifestations of human immunodeficiency virus infection have changed drastically since the introduction of the highly active anti-retroviral therapy (HAART) in developed countries. Recent studies have documented significant reductions in morbidity and mortality rates among HIV-infected patients on HAART. This article focuses on the latest information about the oral manifestations of HIV infection and will discuss the impact of HAART.

  13. Review of mixing length estimates and effects of toroidicity in a fluid model for turbulent transport in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Weiland, J., E-mail: elfjw@chalmers.se [Chalmers University of Technology and EURATOM-VR Association (Sweden)

    2016-05-15

    Basic aspects of turbulent transport in toroidal magnetized plasmas are discussed. In particular the fluid closure has strong effects on zonal flows which are needed to create an absorbing boundary for long wave lengths and also to obtain the Dimits nonlinear upshift. The fluid resonance in the energy equation is found to be instrumental for generating the L–H transition, the spin-up of poloidal rotation in internal transport barriers, as well as the nonlinear Dimits upshift. The difference between the linearly fastest growing mode number and the corresponding longer nonlinear correlation length is also addressed. It is found that the Kadomtsev mixing length result is consistent with the non-Markovian diagonal limit of the transport at the nonlinearly obtained correlation length.

  14. Metabolic and hormonal signatures in pre-manifest and manifest Huntington’s disease patients

    Directory of Open Access Journals (Sweden)

    Rui eWang

    2014-06-01

    Full Text Available Huntington's disease (HD is an inherited neurodegenerative disorder typified by involuntary body movements, and psychiatric and cognitive abnormalities. Many HD patients also exhibit metabolic changes including progressive weight loss and appetite dysfunction. Here we have investigated metabolic function in pre-manifest and manifest HD subjects to establish an HD subject metabolic hormonal plasma signature. Individuals at risk for HD who have had predictive genetic testing showing the cytosine-adenine-guanine (CAG expansion causative of HD, but who do not yet present signs and symptoms sufficient for the diagnosis of manifest HD are said to be pre-manifest. Pre-manifest and manifest HD patients, as well as both familial and non-familial controls, were evaluated for multiple peripheral metabolism signals including circulating levels of hormones, growth factors, lipids and cytokines. Both pre-manifest and manifest HD subjects exhibited significantly reduced levels of circulating growth factors, including growth hormone and prolactin. HD-related changes in the levels of metabolic hormones such as ghrelin, glucagon and amylin were also observed. Total cholesterol, HDL-C and LDL-C were significantly decreased in HD subjects. C-reactive protein was significantly elevated in pre-manifest HD subjects. The observation of metabolic alterations, even in subjects considered to be in the pre-manifest stage of HD, suggests that in addition, and prior, to overt neuronal damage, HD affects metabolic hormone secretion and energy regulation, which may shed light on pathogenesis, and provide opportunities for biomarker development.

  15. Metabolic and hormonal signatures in pre-manifest and manifest Huntington's disease patients.

    Science.gov (United States)

    Wang, Rui; Ross, Christopher A; Cai, Huan; Cong, Wei-Na; Daimon, Caitlin M; Carlson, Olga D; Egan, Josephine M; Siddiqui, Sana; Maudsley, Stuart; Martin, Bronwen

    2014-01-01

    Huntington's disease (HD) is an inherited neurodegenerative disorder typified by involuntary body movements, and psychiatric and cognitive abnormalities. Many HD patients also exhibit metabolic changes including progressive weight loss and appetite dysfunction. Here we have investigated metabolic function in pre-manifest and manifest HD subjects to establish an HD subject metabolic hormonal plasma signature. Individuals at risk for HD who have had predictive genetic testing showing the cytosine-adenine-guanine (CAG) expansion causative of HD, but who do not yet present signs and symptoms sufficient for the diagnosis of manifest HD are said to be "pre-manifest." Pre-manifest and manifest HD patients, as well as both familial and non-familial controls, were evaluated for multiple peripheral metabolism signals including circulating levels of hormones, growth factors, lipids, and cytokines. Both pre-manifest and manifest HD subjects exhibited significantly reduced levels of circulating growth factors, including growth hormone and prolactin. HD-related changes in the levels of metabolic hormones such as ghrelin, glucagon, and amylin were also observed. Total cholesterol, HDL-C, and LDL-C were significantly decreased in HD subjects. C-reactive protein was significantly elevated in pre-manifest HD subjects. The observation of metabolic alterations, even in subjects considered to be in the pre-manifest stage of HD, suggests that in addition, and prior, to overt neuronal damage, HD affects metabolic hormone secretion and energy regulation, which may shed light on pathogenesis, and provide opportunities for biomarker development.

  16. Age-related alterations of relaxation processes and non-Markov effects in stochastic dynamics of R-R intervals variability from human ECGs

    CERN Document Server

    Yulmetyev, R M; Panischev, O Y; Hänggi, P; Yulmetyev, Renat M.; Demin, Sergey A.; Panischev, Oleg Yu.; H\\"anggi, Peter

    2005-01-01

    In this paper we consider the age-related alterations of heart rate variability on the basis of the study of non-Markovian effects. The age dynamics of relaxation processes is quantitatively described by means of local relaxation parameters, calculated by the specific localization procedure. We offer a quantitative informational measure of non-Markovity to evaluate the change of statistical effects of memory. Local relaxation parameters for young and elderly people differ by 3.3 times, and quantitative measures of non-Markovity differ by 4.2 times. The comparison of quantitative parameters allows to draw conclusions about the reduction of relaxation rate with ageing and the higher degree of the Markovity of heart rate variability of elderly people.

  17. CT manifestations of ileal dysgenesis

    Energy Technology Data Exchange (ETDEWEB)

    Oberhelman, Amy P.; Herman, Thomas E.; McAlister, William H. [St. Louis Children' s Hospital, Mallinckrodt Institute of Radiology, Washington University School of Medicine, Department of Radiology, St. Louis, MO (United States); Keating, James P. [St. Louis Children' s Hospital, Mallinckrodt Department of Pediatrics, Washington University School of Medicine, Division of Gastroenterology, St. Louis, MO (United States); Rollins, Michael D.; Dillon, Patrick A. [St. Louis Children' s Hospital, Department of Surgery, Washington University School of Medicine, St. Louis, MO (United States)

    2007-02-15

    Ileal dysgenesis is an uncommon condition of unknown etiology occurring in the distal ileum in the region of the vitelline duct. The CT appearance of this lesion, although not previously described to our knowledge, is characteristic. We report a patient with ileal dysgenesis who had an abdominal CT scan to evaluate chronic iron deficiency anemia and protein-losing enteropathy. Recognition of this lesion by pediatric radiologists is important; so that surgical treatment, which is simple and effective, can be initiated quickly. (orig.)

  18. Neuro-ophthalmic manifestations of prematurity.

    Science.gov (United States)

    Chhablani, Preeti Patil; Kekunnaya, Ramesh

    2014-10-01

    Increasing rates of preterm births coupled with better survival of these infants have resulted in higher prevalence of systemic and ocular complications associated with prematurity. In addition to retinopathy of prematurity, infants who are born preterm may suffer from severe visual impairment as a result of hypoxic ischemic encephalopathy, hypoglycemia, and other metabolic imbalances. The effect of these processes on the anterior visual pathway may result in optic atrophy, optic nerve hypoplasia or optic disc cupping and affection of the posterior visual pathway leads to cortical visual impairment (CVI). Other ocular associations include strabismus, nystagmus, and ocular motor abnormalities such as tonic down gaze and defective saccades and pursuits. Cortical and subcortical involvement also manifests as defects in functional vision and these have not yet been completely understood. Children with CVI may have visual field defects, photophobia, defective visual processing, and deficient color vision. Since most of these children also suffer from additional systemic disabilities, evaluation, and management remains a challenge. However, early diagnosis and initiation of rehabilitation therapy can prove to be of significant benefit in these children.

  19. Neuro-ophthalmic manifestations of prematurity

    Directory of Open Access Journals (Sweden)

    Preeti Patil Chhablani

    2014-01-01

    Full Text Available Increasing rates of preterm births coupled with better survival of these infants have resulted in higher prevalence of systemic and ocular complications associated with prematurity. In addition to retinopathy of prematurity, infants who are born preterm may suffer from severe visual impairment as a result of hypoxic ischemic encephalopathy, hypoglycemia, and other metabolic imbalances. The effect of these processes on the anterior visual pathway may result in optic atrophy, optic nerve hypoplasia or optic disc cupping and affection of the posterior visual pathway leads to cortical visual impairment (CVI. Other ocular associations include strabismus, nystagmus, and ocular motor abnormalities such as tonic down gaze and defective saccades and pursuits. Cortical and subcortical involvement also manifests as defects in functional vision and these have not yet been completely understood. Children with CVI may have visual field defects, photophobia, defective visual processing, and deficient color vision. Since most of these children also suffer from additional systemic disabilities, evaluation, and management remains a challenge. However, early diagnosis and initiation of rehabilitation therapy can prove to be of significant benefit in these children.

  20. Epigenetic manifestations in diet-related disorders.

    Science.gov (United States)

    Mariman, E C M

    2008-01-01

    Epigenetic phenomena are changes in phenotype that are due to resetting of gene expression under the influence of the environment or genetic factors without changing the DNA sequence. Usually this resetting occurs at a certain stage in life and remains fixed thereafter. In humans, evidence for epigenetic involvement in diet-related complex traits and disorders is accumulating. The fetal origins theory indicates that nutrition can influence the later life risk for certain common disorders like the metabolic syndrome. In parent-of-origin effects, the risk for a common disorder like type I diabetes depends on the sex of the parent who transmits genetic risk factors. Interestingly, both dietary and genetic factors can exert their epigenetic influence over several generations. Imprinting, i.e. silencing of one copy of an autosomal pair of genes, can be part of the mechanism pointing to the importance of DNA methylation. In addition, chromatin modifications have been shown to be involved in epigenetic manifestations. The intriguing possibility that diet may influence the direction and extent of epigenetic changes opens new ways for prevention or treatment of common disorders. At the same time, maternal nutrition might be used to actively direct fetal development with consequences for later life performance such as cognitive abilities. More knowledge on those novel applications is needed. This will in part come from novel strategies to map the epigenomic regions, allowing the identification of more genes involved in epigenetics and allowing the study of their response to nutrition.

  1. Subclinical hyperthyroidism and cardiovascular manifestations: a reevaluation of the association.

    Science.gov (United States)

    Carpi, Angelo; Cini, Giuseppe; Russo, Matteo; Antonelli, Alessandro; Gaudio, Carlo; Galetta, Fabio; Franzoni, Ferdinando; Rossi, Giuseppe

    2013-04-01

    Subclinical hyperthyroidism (SH) has been reported associated with atrial fibrillation (AF), heart failure (HF) and coronary heart disease events, including mortality. An expert opinion indicates that AF is the possible link between SH and the other important cardiovascular (CV) manifestations. We analyzed the data of three recent studies including 60,883 subjects of whom 2,284 SH patients. In these subjects, the ratio between the AF events and each of the other above reported CV events varied from 0.14 to 0.4 in SH and from 0.2 to 2.4 in euthyroidism (ET). The general pattern of this ratio in 6 comparisons performed was not significantly higher for SH than ET. This data suggest that AF is not the major link between SH and the related CV manifestations. We suggest that a further link to be considered is the higher frequency of the early atherosclerosis manifestations such as carotid intima media thickness or carotid integrated back scatter, observed in SH. This atherogenic effect of SH can affect the occurrence of all the above clinical CV manifestations.

  2. Effects of low birth weight, maternal smoking in pregnancy and social class on the phenotypic manifestation of Attention Deficit Hyperactivity Disorder and associated antisocial behaviour: investigation in a clinical sample

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    van den Bree Marianne BM

    2007-06-01

    Full Text Available Abstract Background Attention Deficit Hyperactivity Disorder (ADHD is a genetically influenced condition although indicators of environmental risk including maternal smoking during pregnancy, low birth weight and low social class have also been found to be associated with the disorder. ADHD is a phenotypically heterogeneous disorder in terms of the predominant symptom types (inattention, hyperactive-impulsivity, their severity and comorbidity, notably Conduct Disorder. It is possible that these different clinical manifestations of the disorder may arise because of the differing effects of the environmental indicators of environmental risk. We set out to test this hypothesis. Methods In a sample of 356 children diagnosed with ADHD, we sought to investigate possible effects of three indicators of environmental risk – maternal smoking during pregnancy, birth weight and social class – on comorbid Conduct Disorder, conduct disorder symptoms and inattentive and hyperactive-impulsive symptom severity. Results Multiple regression analysis revealed that, after controlling for significant covariates, greater hyperactive-impulsive symptom severity was significantly associated with maternal smoking during pregnancy (r2 = 0.02, Beta = 0.11, t = 1.96, p = 0.05 and social class (r2 = 0.02, Beta = 0.12, t = 2.19, p = 0.03 whilst none of the environmental risk indicators significantly predicted number of inattentive symptoms. Conduct Disorder symptoms were positively predicted by maternal smoking in pregnancy (r2 = 0.04, Beta = 0.18, t = 3.34, p = 0.001 whilst both maternal smoking during pregnancy and social class significantly predicted a diagnosis of Conduct Disorder (OR = 3.14, 95% CI: 1.54, 6.41, Wald = 9.95, p = 0.002 and (OR = 1.95 95% CI: 1.18, 3.23 Wald = 6.78, p = 0.009 respectively. Conclusion These findings suggest that indicators of environmental risk, in this instance maternal smoking in pregnancy and environmental adversity indexed by lower

  3. Cochleovestibular Manifestations in Fabry Disease

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    Alberto Ciceran MD

    2016-09-01

    Full Text Available Fabry disease is a rare, X-linked lysosomal storage disorder resulting from deficient α-galactosidase A activity and globotriaosylceramide accumulation throughout the body. This accumulation leads to various clinical disorders, including inner ear lesions, with sensorineural hearing loss and dizziness. Although hearing loss is recognized in these patients, its incidence and natural history have not been characterized. Hearing disorders develop mainly in adulthood, and tinnitus may be an earlier symptom in Fabry disease. A significant incidence of mid- and high-frequency sensorineural hearing loss in affected males is commonly reported, whereas in female carriers, it is much less frequent. In addition, a high incidence of vestibular disorders with dizziness and chronic instability is also observed in these patients. The few studies about the effects of enzyme replacement therapy (ERT on cochleovestibular symptoms show controversial results. Based on the model of densely stained material accumulation in the inner ear, stria vascularis cell, and organ damage, an early indication of ERT may prevent hearing loss due to the reduction in substrate accumulation.

  4. Cochleovestibular Manifestations in Fabry Disease

    Directory of Open Access Journals (Sweden)

    Alberto Ciceran MD

    2016-09-01

    Full Text Available Fabry disease is a rare, X-linked lysosomal storage disorder resulting from deficient α-galactosidase A activity and globotriaosylceramide accumulation throughout the body. This accumulation leads to various clinical disorders, including inner ear lesions, with sensorineural hearing loss and dizziness. Although hearing loss is recognized in these patients, its incidence and natural history have not been characterized. Hearing disorders develop mainly in adulthood, and tinnitus may be an earlier symptom in Fabry disease. A significant incidence of mid- and high-frequency sensorineural hearing loss in affected males is commonly reported, whereas in female carriers, it is much less frequent. In addition, a high incidence of vestibular disorders with dizziness and chronic instability is also observed in these patients. The few studies about the effects of enzyme replacement therapy (ERT on cochleovestibular symptoms show controversial results. Based on the model of densely stained material accumulation in the inner ear, stria vascularis cell, and organ damage, an early indication of ERT may prevent hearing loss due to the reduction in substrate accumulation.

  5. Odontogenic infections. Complications. Systemic manifestations.

    Science.gov (United States)

    Jiménez, Yolanda; Bagán, José Vicente; Murillo, Judith; Poveda, Rafael

    2004-01-01

    The term, odontogenic infection refers to an infection that originates in the tooth proper or in the tissues that closely surround it; said infection then progresses along the periodontia down to the apex, involving periapical bone and from this area, it then spreads through the bone and periosteum towards near-by or more distant structures. The relevance of this type of infection lies in that it can cause infections that compromise more distant structures (via direct spread and distant spread), for example, intracraneal, retropharyngeal and pulmonary pleural infections. Dissemination by means of the bloodstream can lead to rheumatic problems and deposits on the valves of the heart (endocarditis), etc. The conditions or factors that influence the spread of infection are dependent on the balance between patient-related conditions and microorganism-related conditions. The virulence of the affecting germs is dependent upon their quality and quantity and is one of the microbiological conditions that influences the infection. It is this virulence that promotes infectious invasion and the deleterious effects the microbe will have on the host. Patient-related conditions include certain systemic factors that determine host resistance, which may be impaired in situations such as immunodeficiency syndrome or in brittle diabetes, as well as local factors that will also exert their impact on the spread of the infection.

  6. Musculoskeletal Manifestations in Inflammatory Bowel Disease

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    Giovanni Fornaciari

    2001-01-01

    Full Text Available Muscoloskeletal manifestations are the most common extraintestinal complications of inflammatory bowel disease. Wide ranges in prevalence have been reported, depending on the criteria used to define spondylarthropathy. In 1991, the European Spondylarthropathy Study Group developed classification criteria that included previously neglected cases of undifferentiated spondylarthropathies, which had been ignored in most of the oldest epidemiological studies on inflammatory bowel disease. The spectrum of muscoloskeletal manifestations in inflammatory bowel disease patients includes all of the clinical features of spondylarthropathies: peripheral arthritis, inflammatory spinal pain, dactylitis, enthesitis (Achilles tendinitis and plantar fasciitis, buttock pain and anterior chest wall pain. Radiological evidence of sacroiliitis is common but not obligatory. The articular manifestations begin either concomitantly or subsequent to the bowel disease; however, the onset of spinal disease often precedes the diagnosis of inflammatory bowel disease. The prevalence of the different muscoloskeletal manifestations is similar in ulcerative colitis and Crohn's disease. Symptoms usually disappear after proctocolectomy. The pathogenetic mechanisms that produce the muscoloskeletal manifestations in inflammatory bowel disease are unclear. Several arguments favour an important role of the intestinal mucosa in the development of spondylarthropathy. The natural history is characterized by periods of flares and remission; therefore, the efficacy of treatment is difficult to establish. Most patients respond to rest, physical therapy and nonsteroidal anti-inflammatory drugs, but these drugs may activate bowel disease. Sulphasalazine may be recommended in some patients. There is no indication for the systemic use of steroids.

  7. Articular manifestations in patients with Lyme disease.

    Science.gov (United States)

    Vázquez-López, María Esther; Díez-Morrondo, Carolina; Sánchez-Andrade, Amalia; Pego-Reigosa, Robustiano; Díaz, Pablo; Castro-Gago, Manuel

    To determine the percentage of Lyme patients with articular manifestations in NW Spain and to know their evolution and response to treatment. A retrospective study (2006-2013) was performed using medical histories of confirmed cases of Lyme disease showing articular manifestations. Clinical and laboratory characteristics, together with the treatment and evolution of the patients, were analysed. Seventeen out of 108 LD confirmed patients (15.7%) showed articular manifestations. Regarding those 17 patients, 64.7%, 29.4% and 5.9% presented arthritis, arthralgia and bursitis, respectively. The knee was the most affected joint. Articular manifestations were often associated to neurological, dermatological and cardiac pathologies. Otherwise, most patients were in Stage III. The 11.8% of the cases progressed to a recurrent chronic arthritis despite the administration of an appropriate treatment. Lyme disease patients showing articular manifestations should be included in the diagnosis of articular affections in areas of high risk of hard tick bite, in order to establish a suitable and early treatment and to avoid sequels. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  8. Nocturnal manifestations of atypical parkinsonian disorders.

    Science.gov (United States)

    Bhidayasiri, Roongroj; Jitkritsadakul, Onanong; Colosimo, Carlo

    2014-01-01

    Although nocturnal disturbances are increasingly recognized as an integral part of the continuum of daytime manifestations of Parkinson's disease (PD), there is still little evidence in the medical literature to support the occurrence of these complex phenomena in patients with atypical parkinsonian disorders (APDs). Based on the anatomical substrates in APDs, which are considered to be more extensive outside the basal ganglia than in PD, we might expect that patients with APDs encounter the whole range of nocturnal disturbances, including motor, sleep disorders, autonomic dysfunctions, and neuropsychiatric manifestations at a similar, or even greater, frequency than in PD. This article is a review of the current literature on the problems at nighttime of patients with progressive supranuclear palsy, multiple system atrophy, corticobasal degeneration, and dementia with Lewy bodies. MEDLINE, life science journals and online books were searched by querying appropriate key words. Reports were included if the studies were related to nocturnal manifestations in APDs. Forty articles fulfilled the selection criteria. Differences between these symptoms in APDs and PD are highlighted, given the evidence available about each manifestation. This analysis of nocturnal manifestations of APDs suggests the need for future studies to address these issues to improve the quality of life not only of patients with APDs but the caregivers who encounter the challenges of supporting these patients on a daily basis.

  9. RHEUMATOLOGICAL MANIFESTATIONS OF TYPE 2 DIABETES MELLITUS

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    Gurinder

    2014-01-01

    Full Text Available AIM : To determine the prevalence of rheumatic musculoskeletal manifestations in type 2 diabetic individuals and compare them with non - diabetic individuals. METHODS: 100 type 2 diabetic patients and 100 age and sex matched individuals were included in the study. Complete musculoskeletal examination was carried out which included examinatio n of shoulder joints , hands , back and knees. Patients were also asked to mark the sites of pain on a mannequin. Intensity of pain was marked on a visual analogue scale. These variables were then evaluated using Chi square test . RESULTS : Prevalence of RMS was found to be much higher in case of diabetic individuals except osteoarthritis. 49 patients out of 100 diabetic patients were found to have some form of rheumatic musculoskeletal manifestations. Diabetic cheiroarthropathy was found in the highest number of cases. A significant relation of these manifestations was found with age , duration of diabetes and glycemic control. A significant relation was also found between these manifestations and chronic microangiopathic complications like retinopathy and neph ropathy. CONCLUSION : A detailed examination of musculoskeletal system is an important part of care in patients with type 2 diabetes and some of the manifestations could be a simple and reliable marker of microangiopathic complications like retinopathy and nephropathy.

  10. Novel Cutaneous Manifestations of Pleuroparenchymal Fibroelastosis.

    Science.gov (United States)

    Lowther, Christopher M; Morrison, Annie O; Candelario, Nicole M; Khalafbeigi, Sheva; Cockerell, Clay J

    2016-10-01

    Pleuroparenchymal fibroelastosis (PPFE) is a rare progressive disease that manifests as parenchymal fibrosis of the upper lobe and pleura. Approximately 100 cases have been reported. Cutaneous manifestations of PPFE have not previously been described. Diagnosis is dependent on histologic identification of fibrosis with atypical elastic fibers, necessitating an invasive peripheral lung wedge biopsy.A 68-year-old male with a history of pleuroparenchymal fibroelastosis presented with an asymptomatic, telangiectatic erythematous eruption on bilateral lower extremities. Biopsies demonstrated a subtle perivascular infiltrate with marked increase in atypical elastic fibers, similar to the elastosis in the patient's lungs.This is the first documented case of cutaneous manifestations in PPFE. Clinicians need to be aware that cutaneous eruptions clinically simulating telangiectasia macularis eruptiva perstans but lacking a mast cell infiltrate histologically, may have increased abnormal elastic fibers. Thus, early recognition of these lesions in patients with an undefined restrictive lung disorder, may facilitate the diagnosis of PPFE in some patients.

  11. Vertigo as a Predominant Manifestation of Neurosarcoidosis

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    Tasnim F. Imran

    2015-01-01

    Full Text Available Sarcoidosis is a granulomatous disease of unknown etiology that affects multiple organ systems. Neurological manifestations of sarcoidosis are less common and can include cranial neuropathies and intracranial lesions. We report the case of a 21-year-old man who presented with vertigo and uveitis. Extensive workup including brain imaging revealed enhancing focal lesions. A lacrimal gland biopsy confirmed the diagnosis of sarcoidosis. The patient was initially treated with prednisone, which did not adequately control his symptoms, and then was switched to methotrexate with moderate symptomatic improvement. Our patient had an atypical presentation with vertigo as the predominant manifestation of sarcoidosis. Patients with neurosarcoidosis typically present with systemic involvement of sarcoidosis followed by neurologic involvement. Vertigo is rarely reported as an initial manifestation. This case highlights the importance of consideration of neurosarcoidosis as an entity even in patients that may not have a typical presentation or systemic involvement of disease.

  12. Cutaneous Manifestations of Systemic Lupus Erythematosus

    Science.gov (United States)

    Uva, Luís; Miguel, Diana; Pinheiro, Catarina; Freitas, João Pedro; Marques Gomes, Manuel; Filipe, Paulo

    2012-01-01

    Systemic lupus erythematosus (SLE) is a multiorgan autoimmune disease of unknown etiology with many clinical manifestations. The skin is one of the target organs most variably affected by the disease. The American College of Rheumatology (ACR) established 11 criteria as a classificatory instrument to operationalise the definition of SLE in clinical trials. They were not intended to be used to diagnose individuals and do not do well in that capacity. Cutaneous lesions account for four of these 11 revised criteria of SLE. Skin lesions in patients with lupus may be specific or nonspecific. This paper covers the SLE-specific cutaneous changes: malar rash, discoid rash, photosensitivity, and oral mucosal lesions as well as SLE nonspecific skin manifestations, their pathophysiology, and management. A deeper thorough understanding of the cutaneous manifestations of SLE is essential for diagnosis, prognosis, and efficient management. Thus, dermatologists should cooperate with other specialties to provide optimal care of SLE patient. PMID:22888407

  13. Extrahepatic Manifestations of Primary Biliary Cholangitis.

    Science.gov (United States)

    Chalifoux, Sara L; Konyn, Peter G; Choi, Gina; Saab, Sammy

    2017-03-16

    Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by progressive destruction of the intrahepatic bile ducts, leading to cholestasis. PBC is known to have both hepatic and extrahepatic manifestations. Extrahepatic manifestations are seen in up to 73% of patients with PBC, with the most common being Sjogren's syndrome, thyroid dysfunction and systemic sclerosis. It is thought that patients with PBC are at increased risk of developing these extrahepatic manifestations, almost all of which are autoimmune, because patients with autoimmune disease are at higher risk of developing another autoimmune condition. Due to the high prevalence of extrahepatic diseases in patients with PBC, it is important to complete a thorough medical history at the time of diagnosis. Prompt recognition of extrahepatic disease can lead to improved patient outcomes and quality of life. The following review summarizes the most common extrahepatic conditions associated with PBC.

  14. Main Ocular Manifestations in Rheumatoid Arthritis

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    Sandra Saray Quignon Santana

    2009-12-01

    Full Text Available Rheumatoid arthritis is considered an autoimmune disease in which articular and extra articular manifestations are produced and contribute to alter the functional capacity of the individual. This study consists on performing a bibliographical review showing the main ocular manifestations in patients with rheumatoid arthritis. It is our purpose to give you our experiences to the students as well as the internal medicine, ophthalmology and rheumatologist residents about this topic. The ophthalmological consultation of sick patients contributes to the prevention of ocular illnesses which are characteristic of the base disease and improve the ocular health.

  15. Life-Threatening Cardiac Manifestations of Pheochromocytoma

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    Luiz R. Leite

    2010-01-01

    Full Text Available Pheochromocytoma is a catecholamine-secreting tumor of the adrenal glands, usually with benign manifestations, whose typical clinical presentation includes the triad of headache, palpitations and diaphoresis. However, a wide range of signs and symptoms may be present. In the cardiovascular system, the most common signs are labile hypertension and sinus tachycardia. Systolic heart failure and ST-segment deviations mimicking myocardial infarction have also been reported, as well as QT interval prolongation and, rarely, ventricular tachycardia. We describe a challenging diagnosis of pheochromocytoma with many cardiovascular manifestations, which could have been missed due to the absence of typical symptoms.

  16. 78 FR 11877 - Announcement of Requirements Gathering Meetings for the Electronic Manifest (e-Manifest) System

    Science.gov (United States)

    2013-02-20

    ... such a system, perhaps through the assessment of reasonable service fees or by a similar ``user pays... agency begins the planning stage of the e-Manifest system development process. EPA envisions that e... RCRA Docket is (202) 566- 0270. II. Historical Background on e-Manifest Project For more than a...

  17. The Ocular Manifestations of Drugs Used to Treat Multiple Sclerosis.

    Science.gov (United States)

    Heath, Gregory; Airody, Archana; Gale, Richard Peter

    2017-03-01

    Recent times have seen an increase in the number of options to treat multiple sclerosis. Ocular manifestations of multiple sclerosis are well known to treating physicians; however, the medications used to treat multiple sclerosis can also have ocular side effects. This review article focuses on the ocular manifestations of corticosteroids and disease-modifying agents such as interferon, fingolomod, natalizumab, alemtuzumab and mitoxantron used to treat the disease. The ocular manifestations of multiple sclerosis treatments can be varied depending on the drug used, and include retinopathy, chronic central serous chorioretinopathy, macular oedema, Graves' ophthalmopathy and cortical blindness. These effects may be specific to the drug or secondary to their immunosuppressive effect. The association of macular oedema with fingolomod is clear and merits ocular screening for toxicity. The immunosuppressive nature of the treatments makes patients prone to acquired infections. Hence, if a patient with multiple sclerosis presents with vision loss, infectious and drug-induced aetiology should be considered alongside relapses of multiple sclerosis itself as a cause.

  18. Oropharyngeal Dysphagia: neurogenic etiology and manifestation.

    Science.gov (United States)

    Sebastian, Swapna; Nair, Prem G; Thomas, Philip; Tyagi, Amit Kumar

    2015-03-01

    To determine the type, severity and manifestation of dysphagia in patients with neurogenic etiology. Clinical documentation was done on the different etiologies, its manifestation, assessment findings and management strategies taken for patients with neurogenic oropharyngeal dysphagia who were referred for assessment and management of dysphagia over a period of three months in a tertiary care teaching hospital. Flexible endoscopic examination was done in all the patients. The severity of dysphagia in these patients were graded based on Gugging Swallowing Screen (GUSS). A total of 53 patients with neurogenic oropharyngeal dysphagia were evaluated by an otolaryngologist and a speech language pathologist over a period of three months. The grading of severity based on GUSS for these patients were done. There were 30 patients with recurrent laryngeal nerve injury due to various etiologies, one patient with Neurofibroma-vestibular schwanoma who underwent surgical excision, 16 patients with stroke, two patients with traumatic brain injury, two patients with Parkinsonism and two patients with myasthenia gravis. The manifestation of dysphagia was mainly in the form of prolonged masticatory time, oral transit time, and increased number of swallows required for each bolus, cricopharyngeal spasms and aspiration. Among the dysphagia patients with neurogenic etiology, dysphagia is manifested with a gradual onset and is found to have a progressive course in degenerative disorders. Morbidity and mortality may be reduced with early identification and management of neurogenic dysphagia.

  19. 19 CFR 122.75 - Complete manifest.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Complete manifest. 122.75 Section 122.75 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Documents Required for Clearance and Permission To Depart;...

  20. Rheumatic manifestations associated with lung diseases

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    Marco Aurelio Scarpinella Bueno

    2008-03-01

    Full Text Available Rheumatic manifestations in the more prevalent lung diseasessuch as asthma, chronic pulmonary disease or pneumonia are notfrequent. Exceptions to this rule are represented by lung cancerand sarcoidosis, where the appearance of the digital clubbing,hypertrophic osteoarthropathy, and arthtritis can correspond to thefi rst symptoms of the illness.

  1. Propylthiouracil induced leukocytoclastic vasculitis: A rare manifestation

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    Semra Ayturk

    2013-01-01

    Full Text Available Propylthiouracil (PTU is a common drug used in patients with hyperthyroidism. It may cause perinuclearantineutrophil cytoplasmic antibodies (p-ANCA in few patients with Graves′ disease. This antibody has been associated with different forms of vasculitis. We report a patient who presented with cutaneous manifestations of leukocytoclasticvasculitis with simultaneous development of p-ANCAs during PTU therapy for Graves′ disease.

  2. Imaging the Abdominal Manifestations of Cystic Fibrosis

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    C. D. Gillespie

    2017-01-01

    Full Text Available Cystic fibrosis (CF is a multisystem disease with a range of abdominal manifestations including those involving the liver, pancreas, and kidneys. Recent advances in management of the respiratory complications of the disease has led to a greater life expectancy in patients with CF. Subsequently, there is increasing focus on the impact of abdominal disease on quality of life and survival. Liver cirrhosis is the most important extrapulmonary cause of death in CF, yet significant challenges remain in the diagnosis of CF related liver disease. The capacity to predict those patients at risk of developing cirrhosis remains a significant challenge. We review representative abdominal imaging findings in patients with CF selected from the records of two academic health centres, with a view to increasing familiarity with the abdominal manifestations of the disease. We review their presentation and expected imaging findings, with a focus on the challenges facing diagnosis of the hepatic manifestations of the disease. An increased familiarity with these abdominal manifestations will facilitate timely diagnosis and management, which is paramount to further improving outcomes for patients with cystic fibrosis.

  3. Kerosene poisoning--varied systemic manifestations.

    Science.gov (United States)

    Patel, A L; Shaikh, W A; Patel, H L; Deshmukh, D; Malaviya, A P; Janawar, P; Londhe, V; Dodheja, H

    2004-01-01

    We report here unusual clinical manifestations in a case of kerosene poisoning. The patient presented with encephalopathy and in the course of stay in the hospital developed renal tubular acidosis, delayed first-degree burns and myocarditis. With supportivetherapy the patient recovered completely and was discharged without any sequelae.

  4. [Extra-articular manifestations of seronegative spondylarthritis].

    Science.gov (United States)

    Cammelli, Daniele

    2006-05-01

    Seronegative spondylarthritis are frequently characterised by extra-articular manifestations. They are frequently in recurrent uveitis. Between the cutaneous manifestations should be mentioned erythema nodosum, typical of inflammatory bowel diseases, and keratoderma blenorrhagicum, in the Reiter's syndrome. Cardiac complications in ankylosing spondylitis (AS) include aortic valvular regurgitation and arrhythmia and, more rarely, mitral valvulopathy, cardiomyopathy and pericarditis. Pulmonary involvement in AS includes ventilatory restrictive syndrome and fibro-bullous disease of the apex. Vertebral osteoporosis is a very important extra-articular manifestation because of the possibility of spontaneous fractures of the vertebrae. Central neurological manifestations include medullary compression from cervical sub-luxation while the most important peripheral involvements are lumbar stenosis and the cauda equina syndrome. Type AA amyloidosis is a rare late complication of the AS, possible cause of death especially in patients with aggressive disease. Kidney complications can be observed as consequences of prolonged anti-inflammatory therapy, but the most frequent renal complications are amyloidosis and mesangial IgA segmental and focal glomerulonephritis.

  5. Hepatitis A: clinical manifestations and management.

    Science.gov (United States)

    Jeong, Sook-Hyang; Lee, Hyo-Suk

    2010-01-01

    Due to improved living conditions and subsequent changes in hepatitis A epidemiology, the disease burden of hepatitis A is increasing in many regions. Recently, Korea has faced a large, community-wide outbreak of hepatitis A, which has prompted a vaccination program. The clinical spectrum of hepatitis A virus infection ranges from asymptomatic infection to fulminant hepatitis. Clinical manifestations depend on the age of the host: less than 30% of infected young children are symptomatic, while about 80% of infected adults manifest severe hepatitis with remarkably elevated serum aminotransferases. Fulminant hepatitis is rare, with a reported incidence from 0.015 to 0.5%. Atypical manifestations include relapsing hepatitis and prolonged cholestasis, and complicated cases with acute kidney injury have been reported. Extrahepatic manifestations, such as autoimmune hemolytic anemia, aplastic anemia, pure red cell aplasia, pleural or pericardial effusion, acute reactive arthritis, acute pancreatitis, acalculous cholecystitis, mononeuritis, and Guillain-Barré syndrome, have been rarely reported. Management of hepatitis A includes general supportive care, and critical decisions regarding liver transplantation await further studies on prognostic predictors. Fundamental management of hepatitis A is active vaccination. However, a vaccination program should be adapted to the regional situation, according to differing epidemiology and disease burden.

  6. Extrahepatic manifestations of hepatitis C virus infection.

    Science.gov (United States)

    Zignego, Anna Linda; Craxì, Antonio

    2008-08-01

    Hepatitis C virus may cause hepatic and extrahepatic diseases. Extrahepatic manifestations range from disorders for which a significant association with viral infection is supported by epidemiologic and pathogenetic data, to anecdotal observations without clear proof of causality. This article describes the diagnosis and treatment of these diseases.

  7. The extrahepatic manifestations of hepatitis B virus.

    Science.gov (United States)

    Baig, Saeeda; Alamgir, Mohiuddin

    2008-07-01

    Hepatitis B Virus (HBV) leads to a number of hepatic complications, from acute to chronic hepatitis, cirrhosis and hepatocellular carcinoma, is a well-established fact. Upcoming clinical research, over the years, associates numerous extrahepatic manifestations during the acute and chronic episodes of hepatitis B with significant morbidity and mortality. A causal relationship between HBV and serious autoimmune disorders has also been observed among certain susceptible vaccine recipients in a defined temporal period following immunization. The cause of these extrahepatic manifestations is generally believed to be immune mediated. The most commonly described include skin rash, arthritis, arthralgia, glomerulonephritis, polyarteritis nodosa, and papular acrodermatitis etc. The serum-sickness like "arthritis-dermatitis" prodrome has also been observed in approximately one-third of patients acquiring HBV infections. Skin manifestations of HBV infection typically present as palpable purpura reported to be caused by chronic HBV, although this association remains controversial. To consider the relationship between HBV and other clinically significant disorders as well as serious autoimmune disorders among certain vaccine recipients is the topic of this review. Variable factors that influence extrahepatic manifestation are discussed, including possible synergy between hepatitis B virus and the immune system.

  8. Extrahepatic manifestations of chronic hepatitis B.

    Science.gov (United States)

    Han, Steven-Huy B

    2004-05-01

    Several extrahepatic manifestations are associated with chronic HBV infection, many with significant morbidity and mortality. The cause of these extrahepatic manifestations is generally believed to be immune mediated. PAN is a rare, but serious, systemic complication of chronic HBV affecting the small- and medium-sized vessels. PAN is seen more frequently in North American and European patients and rarely in Asian patients. PAN ultimately involves multiple organ systems, some with devastating consequences, though the hepatic manifestations are often more mild. The optimal treatment of HBV-associated PAN is thought to include a combination of antiviral and immunosuppressive therapies. HBV-associated GN occurs mainly in children, predominantly males, in HBV endemic areas of the world, but is only occasionally reported in the United States. In children, GN is usually self-limited with only rare progression to renal failure. In adults, the natural disease course of GN may be more relentless, slowly progressing to renal failure. Immunosuppressive therapy in HBV-related GN is not recommended, but antiviral therapy with alpha-interferon has shown promise. The serum-sickness like "arthritis-dermatitis" prodrome is seen in approximately one third of patients acquiring HBV. The joint and skin manifestations are varied, but the syndrome spontaneously resolves at the onset of clinical hepatitis with few significant sequelae. Occasionally, arthritis following the acute prodromal infection may persist; however, joint destruction is rare. The association between HBV and mixed essential cryoglobulinemia remains controversial; but a triad of purpura, arthralgias, and weakness, which can progress to nephritis, pulmonary disease, and generalized vasculitis, has characterized the syndrome. Finally, skin manifestations of HBV infection typically present as palpable purpura. Though papular acrodermatitis of childhood has been reported to be caused by chronic HBV, this association

  9. Extrahepatic immune related manifestations in chronic hepatitis C virus infection.

    Science.gov (United States)

    Tampaki, Maria; Koskinas, John

    2014-09-21

    The association of chronic hepatitis C with immune related syndromes has been frequently reported. There is a great range of clinical manifestations affecting various systems and organs such as the skin, the kidneys, the central and peripheral nervous system, the musculoskeletal system and the endocrine glands. Despite the high prevalence of immune related syndromes in patients with chronic hepatitis C, the exact pathogenesis is not always clear. They have been often associated with mixed cryoglobulinemia, a common finding in chronic hepatitis C, cross reaction with viral antigens, or the direct effect of virus on the affected tissues. The aim of this review is to analyze the reported hepatitis C virus immune mediated syndromes, their prevalence and clinical manifestations and to discuss the most supported theories regarding their pathogenesis.

  10. Rydberg atom detection of the temporal coherence of cosmic microwave background radiation

    CERN Document Server

    Tscherbul, Timur V

    2013-01-01

    Rydberg atoms immersed in cold blackbody radiation are shown to display long-lived quantum coherence effects on timescales of tens of picoseconds. By solving non-Markovian equations of motion with no free parameters we obtain the time evolution of the density matrix, and demonstrate that the blackbody-induced temporal coherences manifest as quantum beats in time-resolved fluorescence intensities of the Rydberg atoms. A measurable fluorescence signal can be obtained with a cold trapped ensemble of 1e8 Rydberg atoms subject to 2.7 K cosmic microwave background radiation (CMB), allowing for novel insights into previously unexamined quantum coherence properties of CMB.

  11. 肝硬化并发肝源性糖尿病的临床表现及预后影响%Clinical manifestation and prognostic effect of liver cirrhosis complicated with hepatic diabetes

    Institute of Scientific and Technical Information of China (English)

    尚军洁

    2015-01-01

    Objective To explore clinical manifestations and prognostic effect of liver cirrhosis complicated with hepatic diabetes.Methods 120 patients with liver cirrhosis who were admitted to our hospital from December 2013 to December 2014 were retrospectively analyzed and researched. They were allocated to the liver cirrhosis complicated with hepatic diabetes group and the liver cirrhosis without diabetes group according to the diagnosis of diabetes. Complication, clinical characteristic, liver functional classification, prognostic effect and outcome of patients were analyzed and compared.Results The incidence of liver cirrhosis complicated with hepatic diabetes was 35.8%. In the liver cirrhosis complicated with hepatic diabetes group, incidence of complications (hepatic encephalopathy, gastrointestinal bleeding and electrolyte disorder) was higher and hospitalization time was longer compared with the liver cirrhosis without diabetes group (P<0.05). And mortality rate of the liver cirrhosis complicated with hepatic diabetes group was higher than that of the liver cirrhosis without diabetes group(P<0.05). ConclusionLiver cirrhosis complicated with hepatic diabetes has a high rate of complications and prolonged hospitalization time which do great harm to life quality of patients. It needs to be concerned in clinic.%目的:对肝硬化并发肝源性糖尿病的临床表现及预后影响进行深讨。方法对于2013年12月~2014年12月在我院就诊的肝硬化患者120例进行回顾性分析研究。根据诊断患者是否患有糖尿病将其分为肝硬化并发肝源性糖尿病以及肝硬化无糖尿病组,对各病例的并发症、临床特点、肝功能分级、预后影响以及转归等进行分析比较。结果肝硬化并发肝源性糖尿病发生率为35.8%(43/120)。与无糖尿病组相比,肝硬化并发肝源性糖尿病组并发症(如肝性脑病、消化道出血和电解质紊乱)发生率高且住院时间长(P<0.05)

  12. Pulmonary manifestations of Sjögren's syndrome.

    Science.gov (United States)

    Flament, Thomas; Bigot, Adrien; Chaigne, Benjamin; Henique, Helene; Diot, Elisabeth; Marchand-Adam, Sylvain

    2016-06-01

    In 9-20% of cases, Sjögren's syndrome is associated with various respiratory symptoms. The most typical manifestations are chronic interstitial lung disease (ILD) and tracheobronchial disease. The most common manifestation of ILD is nonspecific interstitial pneumonia in its fibrosing variant. Other types of ILD, such as organising pneumonia, usual interstitial pneumonia and lymphocytic interstitial pneumonitis, are rare. Their radiological presentation is less distinctive, and definitive diagnosis may require the use of transbronchial or surgical lung biopsy. Corticosteroid therapy is the mainstay of ILD treatment in Sjögren's syndrome, but the use of other immunosuppressive drugs needs to be determined. ILD is a significant cause of death in Sjögren's syndrome. Tracheobronchial disease is common in Sjögren's syndrome, characterised by diffuse lymphocytic infiltration of the airway. It is sometimes responsible for a crippling chronic cough. It can also present in the form of bronchial hyperresponsiveness, bronchiectasis, bronchiolitis or recurrent respiratory infections. The management of these manifestations may require treatment for dryness and/or inflammation of the airways. Airway disease has little effect on respiratory function and is rarely the cause of death in Sjögren's syndrome patients. Rare respiratory complications such as amyloidosis, lymphoma or pulmonary hypertension should not be disregarded in Sjögren's syndrome patients.

  13. Pulmonary manifestations of Sjögren's syndrome

    Directory of Open Access Journals (Sweden)

    Thomas Flament

    2016-06-01

    Full Text Available In 9–20% of cases, Sjögren's syndrome is associated with various respiratory symptoms. The most typical manifestations are chronic interstitial lung disease (ILD and tracheobronchial disease. The most common manifestation of ILD is nonspecific interstitial pneumonia in its fibrosing variant. Other types of ILD, such as organising pneumonia, usual interstitial pneumonia and lymphocytic interstitial pneumonitis, are rare. Their radiological presentation is less distinctive, and definitive diagnosis may require the use of transbronchial or surgical lung biopsy. Corticosteroid therapy is the mainstay of ILD treatment in Sjögren's syndrome, but the use of other immunosuppressive drugs needs to be determined. ILD is a significant cause of death in Sjögren's syndrome. Tracheobronchial disease is common in Sjögren's syndrome, characterised by diffuse lymphocytic infiltration of the airway. It is sometimes responsible for a crippling chronic cough. It can also present in the form of bronchial hyperresponsiveness, bronchiectasis, bronchiolitis or recurrent respiratory infections. The management of these manifestations may require treatment for dryness and/or inflammation of the airways. Airway disease has little effect on respiratory function and is rarely the cause of death in Sjögren's syndrome patients. Rare respiratory complications such as amyloidosis, lymphoma or pulmonary hypertension should not be disregarded in Sjögren's syndrome patients.

  14. Cutaneous manifestations in renal failure patients: A case series

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    Banerjee S

    2007-01-01

    Full Text Available Cutaneous involvement in renal disease is due to a host of factors ranging from metabolic disturbances to immunosuppressive drugs. Herein we report a series of six cases of renal failure with varied cutaneous manifestations ranging from infections to neoplasms due to prolonged immunosuppression. Our first case had cutaneous cryptococcosis where skin lesions gave a clue to the diagnosis of altered sensorium and underlying meningitis. The second case initially presented with florid warts and was treated successfully but later presented with an explosive recurrence of skin lesions due to malignant transformation. Our third case had basal cell carcinoma over the presternal region that was successfully treated with liquid nitrogen cryotherapy. Our fourth case had diabetic nephropathy that presented with septicemia and purpura fulminans. The last case had cutaneous manifestations of drug therapy because of heparin infusion. To conclude, cutaneous manifestations in patients with renal failure are varied and a high degree of suspicion is needed for early diagnosis and aggressive treatment to effectively combat mortality and morbidity.

  15. Clinical Manifestations of the Opiate Withdrawal Syndrome

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    Faniya Shigakova

    2015-09-01

    Full Text Available Currently, substance abuse is one of the most serious problems facing our society. The aim of this study was to investigate the clinical manifestations of the opiate withdrawal syndrome (OWS. The study included 112 patients (57 women and 55 men aged from 18 to 64 years with opium addiction according to the DSM-IV. To study the clinical manifestation of OWS, the special 25-score scale with four sections to assess severity of sleep disorders, pain syndrome, autonomic disorders, and affective symptoms was used. Given the diversity of the OWS symptoms, attention was focused on three clinical variants, affective, algic and mixed. The OWS affective variant was registered more frequently in women, while the mixed type of OWS was more typical of men.

  16. A gingival manifestation of histoplasmosis leading diagnosis

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    Marco Tullio Brazão-Silva

    2013-01-01

    Full Text Available Histoplasmosis is a world-wide distributed deep mycosis caused by Histoplasma capsulatum which has been endemic in many countries. We present a case involving an immunocompetent man evidencing the necessity of a multidisciplinary approach and rational requisition of exams. The disease has started as a pulmonary disease mimicking tuberculosis, although the exams have been negative. Immunodiffusion test indicate histoplasmosis, not confirmed by culture of sputum. After days the patient was forwarded by a private doctor for evaluation of oral lesions at our Department of Stomatology. An incisional biopsy revealed a nonspecific granulomatous inflammation and the Grocott-Gomori methenamine silver stain identified scarce oval structures that could represent fungal yeast. Sampling oral lesions with swab, it was observed the typical growth of H. capsulatum on culture. This case highlights the importance of doctor′s integration diagnosing histoplasmosis, while a wide spectrum of clinical manifestations should be expected. Oral lesions may be the critical manifestation leading diagnosis.

  17. The chronic gastrointestinal manifestations of Chagas disease

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    Nilce Mitiko Matsuda

    2009-01-01

    Full Text Available Chagas disease is an infectious disease caused by the protozoan Trypanosoma cruzi. The disease mainly affects the nervous system, digestive system and heart. The objective of this review is to revise the literature and summarize the main chronic gastrointestinal manifestations of Chagas disease. The chronic gastrointestinal manifestations of Chagas disease are mainly a result of enteric nervous system impairment caused by T. cruzi infection. The anatomical locations most commonly described to be affected by Chagas disease are salivary glands, esophagus, lower esophageal sphincter, stomach, small intestine, colon, gallbladder and biliary tree. Chagas disease has also been studied in association with Helicobacter pylori infection, interstitial cells of Cajal and the incidence of gastrointestinal cancer.

  18. Cutaneous manifestations of Helicobacter cinaedi infection.

    Science.gov (United States)

    Shimizu, Satoko; Inokuma, Daisuke; Watanabe, Mika; Sakai, Toshiya; Yamamoto, Satoshi; Tsuchiya, Kikuo; Shimizu, Hiroshi

    2013-03-27

    Helicobacter cinaedi causes gastroenteritis and bacter-aemia, particularly in immunocompromised individuals. Although cellulitis is sometimes reported to accompany infection by this pathogen, the cutaneous manifestations are poorly understood. To clarify the characteristic cutaneous features, 47 cases of H. cinaedi bacteraemia experienced at Sapporo City General Hospital as nosocomial infection were retrospectively evaluated. Thirty-four percent (16 cases) of the patients showed cutaneous lesions. They all had sudden onset of erythemas accompanied by high temperature. The most common cutaneous manifestations were found to be superficial cellulitis, which results in painful erythemas or infiltrated erythematous plaques on the extremities. These skin lesions can be an early clinical indicator of H. cinaedi bacteraemia in the setting of nosocomial infection.

  19. Clinical manifestations, diagnosis, and treatment of neurocysticercosis.

    Science.gov (United States)

    Sotelo, Julio

    2011-12-01

    Neurocysticercosis (NCC) is the most frequent parasitic disease of the human brain. Modern imaging studies, CT and MRI, have defined the diagnosis and characterization of the disease. Through these studies the therapeutic approach for each case may be individualized with the aid of antihelmintics, steroids, symptomatic medicines, or surgery. The use of one or various therapeutic measures largely depends on the peculiar combination of number, location, and biological stage of lesions as well as the degree of inflammatory response to the parasites. Although there is not a typical clinical picture of NCC, epilepsy is the most frequent manifestation of parenchymal NCC, whereas hydrocephalus is the most frequent manifestation of meningeal NCC. Eradication of cysticercosis is an attainable goal by public education and sanitary improvement in endemic areas.

  20. Atypical Manifestations in Glut1 Deficiency Syndrome.

    Science.gov (United States)

    De Giorgis, V; Varesio, C; Baldassari, C; Piazza, E; Olivotto, S; Macasaet, J; Balottin, U; Veggiotti, P

    2016-08-01

    Glucose transporter type 1 deficiency syndrome is a genetically determined, treatable, neurologic disorder that is caused by an insufficient transport of glucose into the brain. It is caused by a mutation in the SCL2A1 gene, which is so far the only known to be associated with this condition. Glucose transporter type 1 deficiency syndrome consists of a wide clinical spectrum that usually presents with cognitive impairment, epilepsy, paroxysmal exercise-induced dyskinesia, acquired microcephaly, hemolytic anemia, gait disturbance, and dyspraxia in different combinations. However, there are other clinical manifestations that we consider equally peculiar but that have so far been poorly described in literature. In this review, supported by a video contribution, we will accurately describe this type of clinical manifestation such as oculogyric crises, weakness, paroxysmal kinesigenic and nonkinesigenic dyskinesia in order to provide an additional instrument for a correct, rapid diagnosis. © The Author(s) 2016.

  1. Clinical Manifestations and Diagnosis of Acromegaly

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    Gloria Lugo

    2012-01-01

    Full Text Available Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Acromegaly is a disabling disease that is associated with increased morbidity and reduced life expectancy. The diagnosis is based primarily on clinical features and confirmed by measuring GH levels after oral glucose loading and the estimation of IGF-I. It has been suggested that the rate of mortality in patients with acromegaly is correlated with the degree of control of GH. Adequately treated, the relative mortality risk can be markedly reduced towards normal.

  2. ORAL MANIFESTATIONS AMONG ROMANIAN HIV PATIENTS

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    Manuela ARBUNE

    2013-03-01

    Full Text Available The objective of the study is to evaluate the oral health problems on HIV youth patients from Galati. Materials and method. A cross-sectional study assessed 102 patients with mean age 22. The most frequent oral manifestations on HIV infected youth under ART are erythema marginatum, periodontitis, candidosis and hypertrophia gingivalis. Results and discussion. Dental decay-missing-filled index on HIV patients is high. Viral HIV replication, long time pediatric exposure on HIV, male sex, smoking, and oral inflamation are related to dental poor condition. Exodontic therapy is comon among HIV youth. However, persistence of some associated oral infections is related to individual or behavioral risk factors, but also to some newly found mechanisms, such as disfunctional immune reconstruction. Seeing to antiretroviral treatment, the severity and frequency of oral manifestations decreased among HIV patients on antiretroviral treatment. Conclusions. Developing medical, social and educational programs is imperative for improving the oral health of HIV youth of Galati.

  3. Pattern of cutaneous manifestations in diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Goyal Abhishek

    2010-01-01

    Full Text Available Background: Diabetes mellitus affects individuals of all ages and socioeconomic status. Skin is affected by the acute metabolic derangements as well as by chronic degenerative complications of diabetes. Aims: To evaluate the prevalence of skin manifestations in patients with diabetes mellitus. To analyze the prevalence and pattern of skin disorders among diabetic patients from this region of Western Himalayas. Materials and Methods: One hundred consecutive patients with the diagnosis of diabetes mellitus and having skin lesions, either attending the diabetic clinic or admitted in medical wards were included in this study. Results: The common skin disorders were: x0 erosis (44%, diabetic dermopathy (36%, skin tags (32%, cutaneous infections (31%, and seborrheic keratosis (30%. Conclusion: Skin is involved in diabetes quite often and the manifestations are numerous. High prevalence of xerosis in our diabetic population is perhaps due to cold and dry climatic conditions in the region for most of the time in the year.

  4. Varied Clinical Manifestations of Amebic Colitis.

    Science.gov (United States)

    Cooper, Chad J; Fleming, Rhonda; Boman, Darius A; Zuckerman, Marc J

    2015-11-01

    Invasive amebiasis is common worldwide, but infrequently observed in the United States. It is associated with considerable morbidity in patients residing in or traveling to endemic areas. We review the clinical and endoscopic manifestations of amebic colitis to alert physicians to the varied clinical manifestations of this potentially life-threatening disease. Copyright ©Most patients present with watery or bloody diarrhea. Less common presentations of amebic colitis include abdominal pain, overt gastrointestinal bleeding, exacerbation of inflammatory bowel disease, or the incidental association with colon cancer. Amebic liver abscesses are the most frequent complication. Rectosigmoid involvement may be found on colonoscopy; however, most case series have reported that the cecum is the most commonly involved site, followed by the ascending colon. Endoscopic evaluation should be used to assist in the diagnosis, with attention to the observation of colonic inflammation, ulceration, and amebic trophozoites on histopathological examination.

  5. Clinical manifestations and diagnosis of acromegaly.

    Science.gov (United States)

    Lugo, Gloria; Pena, Lara; Cordido, Fernando

    2012-01-01

    Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Acromegaly is a disabling disease that is associated with increased morbidity and reduced life expectancy. The diagnosis is based primarily on clinical features and confirmed by measuring GH levels after oral glucose loading and the estimation of IGF-I. It has been suggested that the rate of mortality in patients with acromegaly is correlated with the degree of control of GH. Adequately treated, the relative mortality risk can be markedly reduced towards normal.

  6. Thoracic manifestations of ovarian hyperstimulation syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Levin, M.F.; Hutton, L.C.; Kaplan, B.R. [University of Western Ontario, London, ON (Canada)

    1995-02-01

    In order to determine the thoracic manifestations of severe ovarian hyperstimulation syndrome, the medical records and available images of 771 patients who had received gonadotropins to induce superovulation, were reviewed. In 22 patients (3%) severe hyperstimulation syndrome was diagnosed clinically and confirmed with ultrasonography (US). Pleural effusion occurred in five of these (23%), one of whom required thoracentesis. Atelectasis and internal jugular vein thrombosis developed in one patient, and ventilation-perfusion mismatch occurred in another. The study concluded that respiratory distress in patients with ovarian hyperstimulation syndrome was most likely due to lung restriction. Pulmonary manifestations formed an important part of this syndrome, and radiologic input were considered necessary for assessment, monitoring and management. 10 refs., 2 figs., 1 tab.

  7. Clinical Manifestations and Diagnosis of Acromegaly

    Science.gov (United States)

    Lugo, Gloria; Pena, Lara; Cordido, Fernando

    2012-01-01

    Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Acromegaly is a disabling disease that is associated with increased morbidity and reduced life expectancy. The diagnosis is based primarily on clinical features and confirmed by measuring GH levels after oral glucose loading and the estimation of IGF-I. It has been suggested that the rate of mortality in patients with acromegaly is correlated with the degree of control of GH. Adequately treated, the relative mortality risk can be markedly reduced towards normal. PMID:22518126

  8. [Cerebrotendinous xanthomatosis: physiopathology, clinical manifestations and genetics].

    Science.gov (United States)

    Preiss, Yudith; Santos, José L; Smalley, Susan V; Maiz, Alberto

    2014-05-01

    Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disease, caused by genetic deficiency of the 27-hydroxylase enzyme (encoded by CYP27A1). It plays a key role in cholesterol metabolism, especially in bile acid synthesis and in the 25-hydroxylation of vitamin D3 in the liver. Its deficiency causes reduced bile acid synthesis and tissue accumulation of cholestanol. Clinical manifestations are related to the presence of cholestanol deposits and include tendon xanthomas, premature cataracts, chronic diarrhea, progressive neurologic impairment and less frequently coronary heart disease, early onset osteoporosis and abnormalities in the optic disk and retina. An early diagnosis and treatment with quenodeoxycholic acid may prevent further complications, mainly neurological manifestations. This review summarizes cholesterol metabolism related to bile acid synthesis, physiopathology, biochemistry and treatment of cerebrotendinous xanthomatosis.

  9. Cutaneous manifestations of familial amyloidotic polyneuropathy.

    Science.gov (United States)

    Rocha, N; Velho, G; Horta, M; Martins, A; Massa, A

    2005-09-01

    Familial amyloidotic polyneuropathy is an autosomal dominant amyloidosis, characterized by the systemic deposition of amyloid with a particular involvement of the peripheral nerves. The disease generally manifests as a severe sensory, motor and autonomic neuropathy. Cardiomyopathy, nephropathy, vitreous opacities and carpal tunnel syndrome may occur in a variable association with the neuropathy. Trophic dermatological lesions are frequent in the more advanced stages of the disease. We examined the skin of 142 patients. The cutaneous manifestations more frequently observed were: xerosis (81.6%), seborrheic dermatitis (21.8%), traumatic and burn lesions (19.7%), acne (18.3%), neurotrophic ulcers (14%) and onychomycosis (10.5%). Among the hepatic transplanted patients (31%), seborrheic dermatitis and acne were the most frequent diagnoses.

  10. [Multiple sclerosis: pathogenesis and manifestations in children].

    Science.gov (United States)

    Brissaud, O; Palin, K; Chateil, J F; Pedespan, J M

    2001-09-01

    Multiple sclerosis (MS) is rare in children and occurs exceptionally before ten years. Sex ratio (girl/boy) is around 2.5 to 3, higher than in adults. Brain stem dysfunction and meningeal symptoms are more commonly first manifestations of the disease than in adults. Optic neuritis is also a frequent early manifestation. The etiology of the disease remains unclear and none of the advanced hypotheses (infectious, genetic, environmental) can by themselves explain its occurrence. There is a genetic susceptibility which is probably linked to many genes leading to a low related risk (less than two). A viral trigger mechanism in a person with a genetic predisposition is possible. New therapies result from a better understanding of the closed immune mechanisms of the disease.

  11. Oral manifestations of HIV positive children.

    Science.gov (United States)

    Magalhães, M G; Bueno, D F; Serra, E; Gonçalves, R

    2001-01-01

    Oral manifestations in HIV positive children were observed in thirty-eight HIV infected children that have received care at the Special Care Dentistry Center (SCDC) of the School of Dentistry, University of Sao Paulo. Results have shown that 52.63% of the children presented at least one oral manifestation related with HIV/AIDS. Angular cheilitis occurred in 28.94%, parotid gland bilateral enlargement, pseudomembranous candidiasis and erythematous candidiasis in 18.42%, conventional gingivitis in 13.15%, herpes simplex in 5.26%, hairy leukoplakia, recurrent aphthous ulcer and condyloma acuminatum in 2.63%. Although enamel hypoplasia occurred in 23.68%, this could not be attributed specifically to HIV infection.

  12. Extra-pulmonary manifestations of sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    Vardhanabhuti, V. [Radiology Department, Derriford Hospital, Plymouth (United Kingdom); Venkatanarasimha, N. [St Michael' s Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8 (Canada); Bhatnagar, G.; Maviki, M.; Iyengar, S.; Adams, W.M. [Radiology Department, Derriford Hospital, Plymouth (United Kingdom); Suresh, P., E-mail: sureshpriya2000@yahoo.com [Radiology Department, Derriford Hospital, Plymouth (United Kingdom)

    2012-03-15

    Although, the diagnosis and evaluation of sarcoidosis has traditionally remained confined to the chest, its multi-system nature has been widely recognized. Radiological features of pulmonary sarcoidosis are well known but extra-pulmonary manifestations can produce a plethora of non-specific imaging findings that can affect subcutaneous tissue, and the neurological, cardiac, gastrointestinal, urological, liver, spleen, and skeletal systems. In the literature, there are various case reports and specific system reviews but there are few reviews that encompass all the extra-pulmonary manifestations. In this paper, we comprehensively review the imaging features of extra-pulmonary sarcoidosis with characteristic features as well as atypical presentations. In addition, we discuss the emerging role of nuclear medicine in sarcoidosis.

  13. Clinical and radiological manifestations of paraneoplastic syndrome of bronchogenic carcinoma

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    Goldner Branislav

    2005-01-01

    Full Text Available The objective of this study was to present some clinical and radiological manifestations of PNS in relation to bronchogenic carcinoma (BC and to evaluate the usefulness of imaging findings in the diagnosis of asymptomatic BC. In the study group of 204 patients (146 male and 58 female with proven bronchogenic carcinoma, PNS was present in 18 (8.62% patients. The patients with PNS were divided into two groups. The first one consisted of 13 (72.2% patients with symptoms related to primary tumours while the second one consisted of 5 (27.7% patients with symptoms, at initial appearance, indicative of disorders of other organs and systems. The predominant disorder was Lambert-Eaton Syndrome, associated with small-cell carcinoma. Endocrine manifestations included: inappropriate antidiuretic hormone production syndrome (small-cell carcinoma, a gonadotropin effect with gynaecomastia and testicular atrophy (planocellular carcinoma, small-cell carcinoma, a case of Cushing Syndrome (small-cell carcinoma, and hyper-calcaemia, due to the production of the parathyroid hormone-related peptide, which was associated with planocellular carcinoma. A rare case of bilateral exophthalmos was found as PNS at adenocarcinoma. Digital clubbing and hypertrophic osteoarthropathy (HO were associated with planocellular and adenocarcinoma, while clubbing was much more common than HO, especially among women. The differences between the two groups were related to the time of PNS appearance. In the first group, PNS occurred late on in the illness, while in the second group, PNS preceded the diagnosis of BC. Alternatively, the disappearance of a clinical or a radiological manifestation of PNS after surgery or chemotherapy may be an indicator of an improvement in health or PNS may be the first sign of illness recurrence. Radiological manifestations of PNS in asymptomatic patients may serve as a useful screen for identifying primary BC. In symptomatic patients, it may be an

  14. Palmse viinaköögi manifest

    Index Scriptorium Estoniae

    1996-01-01

    Manifest. Tõlkijate seminari puhul 17. mail 1996 Palmse viinaköögis Juta Bedia, Eric Dickens, Gyözö Fehérvári, Guntars Godinsh, Maima Grinberga, Irja Grönholm, Leif Hannibal, Cornelius Hasselblatt, Pirkko Huurto, Ivo Iliste, Nora Javorskaja, Gisbert Jänicke, Kaisu Lahikainen, Enel Melberg, Vera Ruber, Arnold Tamm, Leili Tamm, Jonatan Tomesh, Lilia Velic'kova, Marianne Vogel. Inglise k.: Estonian Literary Magazine, autumn 1996, nr. 3

  15. Hypersensitivity manifestations to the fruit mango

    OpenAIRE

    Sareen, Richa; SHAH, ASHOK

    2011-01-01

    The objectives of this study are 1) To review the published data and document the current knowledge on allergic manifestations to the fruit mango 2) To highlight the two distinct clinical presentations of hypersensitivity reactions caused by mango 3) To discuss the role of cross-reactivity 4) To increase awareness of potentially life threatening complications that can be caused by allergy to mango. An extensive search of the literature was performed in Medline/PubMed with the key terms "mango...

  16. Catatonia: an unusual manifestation of Wilson's disease.

    Science.gov (United States)

    Basu, Aniruddha; Thanapal, Sivakumar; Sood, Mamta; Khandelwal, Sudhir K

    2015-01-01

    Wilson's disease, characterized by abnormal copper accumulation in the human body, may present with psychiatric manifestations in about one-fifth of patients. The authors report a patient with Wilson's disease who initially presented with acute psychosis and later developed catatonic symptoms. The atypical presentation led to a delay in diagnosis and institution of appropriate treatment. Wilson's disease can be ruled out in all young patients presenting with psychiatric symptoms for the first time by screening for a Kayser-Fleischer ring.

  17. [Cursive and gelastic manifestations of epilepsies].

    Science.gov (United States)

    Guerreiro, C A; Silveira, D C; Guerreiro, M M

    1987-12-01

    Seven cases of cursive and two cases of gelastic manifestations of epileptic seizures are presented. The cases were documented with computerized tomography and electroencephalography (EEG). Most of patients with cursive seizures showed temporal lobe epileptiform discharge in EEG. The authors discuss the theme in relation to pathophysiology and conclude that they are not a homogeneous group according to prognosis and nosology. Every case presented complex partial seizures with or without tonic-clonic seizures.

  18. Palmse viinaköögi manifest

    Index Scriptorium Estoniae

    1996-01-01

    Manifest. Tõlkijate seminari puhul 17. mail 1996 Palmse viinaköögis Juta Bedia, Eric Dickens, Gyözö Fehérvári, Guntars Godinsh, Maima Grinberga, Irja Grönholm, Leif Hannibal, Cornelius Hasselblatt, Pirkko Huurto, Ivo Iliste, Nora Javorskaja, Gisbert Jänicke, Kaisu Lahikainen, Enel Melberg, Vera Ruber, Arnold Tamm, Leili Tamm, Jonatan Tomesh, Lilia Velic'kova, Marianne Vogel. Inglise k.: Estonian Literary Magazine, autumn 1996, nr. 3

  19. Tardive Dystonia: Clinical Spectrum and Novel Manifestations

    Directory of Open Access Journals (Sweden)

    R. Jeffrey Davis

    1988-01-01

    Full Text Available Tardive dystonia was identified in 25 patients: involvement of the face and neck was most common; truncal and limb dystonia were also observed. There were 3 cases of laryngospasm and 2 of spasmodic dysphonia. The latter has not been previously reported as a manifestation of tardive dystonia. In all cases, movements typical of classic tardive dyskinesia could be demonstrated. This group illustrates the variety of dystonic disorders that may occur in conjunction with tardive dyskinesia.

  20. Atypical manifestations of multiple myeloma: Radiological appearance

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Thomas [Department of Radiology, St-Vincenz Hospital, Auf dem Schafsberg, D-65549 Limburg (Germany)]. E-mail: t.hess@st-vincenz.de; Egerer, Gerlinde [Department of Internal Medicine V, Haematology/Oncology, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Kasper, Bernd [Department of Internal Medicine V, Haematology/Oncology, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Rasul, Kakil Ibrahim [Hamad Medical Center, Moha (Qatar); Goldschmidt, Hartmut [Department of Internal Medicine V, Haematology/Oncology, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Kauffmann, G.W. [Department of Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany)

    2006-05-15

    Diagnostic procedures performed on patients with multiple myeloma typically reveal lytic bone lesions, osteopenia or osteoporosis, bone marrow infiltration by plasma cells as well as overproduction of immunoglobulin or light chains in the serum or urine. Skeletal manifestations are extremely variable and the unusual forms have been described extensively. Extramedullary plasma-cell tumours (plasmocytoma) are found in about 5% of newly diagnosed patients with multiple myelomas. In this paper we present eight patients with atypical forms of multiple myeloma.