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Sample records for modeling sudden depressurization

  1. Numerical studies of depressurization-induced gas production from an interbedded marine turbidite gas hydrate reservoir model

    Science.gov (United States)

    Myshakin, Evgeniy; Lin, Jeen-Shang; Uchida, Shun; Seol, Yongkoo; Collett, Timothy S.; Boswell, Ray

    2017-01-01

    The numerical simulation of thin hydrate-bearing sand layers interbedded with mud layers is investigated. In this model, the lowest hydrate layer occurs at the base of gas hydrate stability and overlies a thinly-interbedded saline aquifer. The predicted gas rates reach 6.25 MMscf/day (1.77 x 105 m3 /day) after 90 days of continuous depressurization with manageable water production. Development of horizontal dissociating interfaces between hydrate-bearing sand and mud layers is a primary determinant of reservoir performance. A set of simulations has been executed to assess uncertainty in in situ permeability and to determine the impact of the saline aquifer on productivity.

  2. Numerical Simulation of Methane Production from Hydrates Induced by Different Depressurizing Approaches

    Directory of Open Access Journals (Sweden)

    Yanghui Li

    2012-02-01

    Full Text Available Several studies have demonstrated that methane production from hydrate-bearing porous media by means of depressurization-induced dissociation can be a promising technique. In this study, a 2D axisymmetric model for simulating the gas production from hydrates by depressurization is developed to investigate the gas production behavior with different depressurizing approaches. The simulation results showed that the depressurization process with depressurizing range has significant influence on the final gas production. On the contrary, the depressurizing rate only affects the production lifetime. More amount of cumulative gas can be produced with a larger depressurization range or lowering the depressurizing rate for a certain depressurizing range. Through the comparison of the combined depressurization modes, the Class 2 (all the hydrate dissociation simulations are performed by reducing the initial system pressure with the same depressurizing range initially, then to continue the depressurization process conducted by different depressurizing rates and complete when the system pressure decreases to the atmospheric pressure is much superior to the Class 1 (different depressurizing ranges are adopted in the initial period of the gas production process, when the pressure is reduced to the corresponding value of depressurization process at the different depressurizing range, the simulations are conducted at a certain depressurizing rate until the pressure reaches the atmospheric pressure for a long and stable gas production process. The parameter analysis indicated that the gas production performance decreases and the period of stable production increases with the initial pressure for the case of depressurizing range. Additionally, for the case of depressurizing range, the better gas production performance is associated with higher ambient temperature for production process, and the effect of thermal conductivity on gas production performance can be

  3. Sediment–well interaction during depressurization

    KAUST Repository

    Shin, Hosung

    2016-10-05

    Depressurization gives rise to complex sediment–well interactions that may cause the failure of wells. The situation is aggravated when high depressurization is imposed on sediments subjected to an initially low effective stress, such as in gas production from hydrate accumulations in marine sediments. Sediment–well interaction is examined using a nonlinear finite element simulator. The hydro-mechanically coupled model represents the sediment as a Cam-Clay material, uses a continuous function to capture compressibility from low to high effective stress, and recognizes the dependency of hydraulic conductivity on void ratio. Results highlight the critical effect of hydro-mechanical coupling as compared to constant permeability models: A compact sediment shell develops against the screen, the depressurization zone is significantly smaller than the volume anticipated assuming constant permeability, settlement decreases, and the axial load on the well decreases; in the case of hydrates, gas production will be a small fraction of the mass estimated using a constant permeability model. High compressive axial forces develop in the casing within the production horizon, and the peak force can exceed the yield capacity of the casing and cause its collapse. Also tensile axial forces may develop in the casing above the production horizon as the sediment compacts in the depressurized zone and pulls down from the well. Well engineering should consider: slip joints to accommodate extensional displacement above the production zone, soft telescopic/sliding screen design to minimize the buildup of compressive axial force within the production horizon, and enlarged gravel pack to extend the size of the depressurized zone.

  4. Experimental Dissociation of Methane Hydrates Through Depressurization

    Science.gov (United States)

    Borgfeldt, T.; Flemings, P. B.; Meyer, D.; You, K.

    2015-12-01

    We dissociated methane hydrates by stepwise depressurization. The initial hydrates were formed by injecting gas into a cylindrical sample of brine-saturated, coarse-grained sand at hydrate-stable conditions with the intention of reaching three-phase equilibrium. The sample was initially at 1°C with a pore pressure of 1775 psi and a salinity of 7 wt. % NaBr. The depressurization setup consisted of one pump filled with tap water attached to the confining fluid port and a second pump attached to the inlet port where the methane was injected. Depressurization was conducted over sixteen hours at a constant temperature of 1°C. The pore pressure was stepwise reduced from 1775 psi to atmospheric pressure by pulling known volumes of gas from the sample. After each extraction, we recorded the instantaneous and equilibrium pore pressure. 0.503 moles of methane were removed from the sample. The pore pressure decreased smoothly and nonlinearly with the cumulative gas withdrawn from the sample. We interpret that hydrate began to dissociate immediately with depressurization, and it continued to dissociate when the pressure decreased below the three-phase pressure for 1°C and 0 wt. % salinity. Two breaks in slope in the pressure vs. mass extracted data are bounded by smooth, nonlinear curves with differing slopes on either side. We attribute the breaks to dissociation of three zones of hydrate concentration. We created a box model to simulate the experimental behavior. For a 10% initial gas saturation (estimated from the hydrate formation experiment and based on mass conservation), an initial hydrate saturation of 55% is required to match the total methane extracted from the sample. Future experiments will be conducted over a longer timespan while monitoring hydrate dissociation with CT imaging throughout the process.

  5. Sudden death of entanglement of a quantum model

    Institute of Scientific and Technical Information of China (English)

    Zhang Guo-Feng

    2007-01-01

    In this paper the so-called sudden death effect of entanglement is investigated in a quantum model. The results show that one can expect the resurrection of the original entanglement to occur in a periodic way following each sudden death event. The length of the time interval for the zero entanglement depends not only on the degree of entanglement of the initial state but also on the initial state.

  6. One-dimensional modeling of radial heat removal during depressurized heatup transients in modular pebble-bed and prismatic high temperature gas-cooled reactors

    Energy Technology Data Exchange (ETDEWEB)

    Savage, M.G.

    1984-07-01

    A one-dimensional computational model was developed to evaluate the heat removal capabilities of both prismatic-core and pebble-bed modular HTGRs during depressurized heatup transients. A correlation was incorporated to calculate the temperature- and neutron-fluence-dependent thermal conductivity of graphite. The modified Zehner-Schluender model was used to determine the effective thermal conductivity of a pebble bed, accounting for both conduction and radiation. Studies were performed for prismatic-core and pebble-bed modular HTGRs, and the results were compared to analyses performed by GA and GR, respectively. For the particular modular reactor design studied, the prismatic HTGR peak temperature was 2152.2/sup 0/C at 38 hours following the transient initiation, and the pebble-bed peak temperature was 1647.8/sup 0/C at 26 hours. These results compared favorably with those of GA and GE, with only slight differences caused by neglecting axial heat transfer in a one-dimensional radial model. This study found that the magnitude of the initial power density had a greater effect on the temperature excursion than did the initial temperature.

  7. Sudden interaction quench in the quantum sine-Gordon model

    Energy Technology Data Exchange (ETDEWEB)

    Sabio, Javier [Instituto de Ciencia de Materiales de Madrid (CSIC), Sor Juana Ines de la Cruz 3, E-28049 Madrid (Spain); Kehrein, Stefan, E-mail: javier.sabio@icmm.csic.e [Arnold-Sommerfeld-Center for Theoretical Physics, Center for NanoSciences and Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, Theresienstrasse 37, 80333 Muenchen (Germany)

    2010-05-15

    We study a sudden interaction quench in the weak-coupling regime of the quantum sine-Gordon model. The real time dynamics of the bosonic mode occupation numbers is calculated using the flow equation method. While we cannot prove results for the asymptotic long-time limit, we can establish the existence of an extended regime in time where the mode occupation numbers relax to twice their equilibrium values. This factor two indicates a non-equilibrium distribution and is a universal feature of weak interaction quenches. The weak-coupling quantum sine-Gordon model therefore turns out to be on the borderline between thermalization and non-thermalization.

  8. Sudden infant death syndrome prevention: a model program for NICUs.

    Science.gov (United States)

    McMullen, Sherri L; Lipke, Bethann; LeMura, Catherine

    2009-01-01

    Health care providers' opinions can influence how parents place their infant to sleep. Neonatal nurses can improve how they teach and model safe infant sleep practices to parents. To increase neonatal nurses' knowledge, a sudden infant death syndrome (SIDS) prevention program was implemented. Program components included a computerized teaching tool, a crib card, sleep sacks, and discharge instructions. Initial program evaluation showed that 98 percent of infants slept supine and 93 percent slept in sleep sacks in open cribs. However, nurses continued to swaddle some infants with blankets to improve thermoregulation. To increase nursing compliance in modeling safe infant sleep practices, Halo SleepSack Swaddles were provided for nurses to use in place of a blanket to regulate infant temperature. Recent data show that 100 percent of infants in open cribs are now sleeping supine wearing a Halo Swaddle or a traditional Halo SleepSack. This model program can easily be replicated to enhance neonatal nurses' knowledge about SIDS prevention.

  9. Defining the Sudden Stratospheric Warming in Climate Models

    Science.gov (United States)

    Kim, J.; Son, S. W.; Gerber, E. P.; Park, H. S.

    2016-12-01

    A sudden stratospheric warming (SSW) is defined by the World Meteorological Organization (WMO) as zonal-mean zonal wind reversal at 10 hPa and 60°N, associated with a reversal of the climatological temperature gradient at this elevation. This wind criterion in particular has been applied to reanalysis data and climate model output during the last few decades. In the present study, it is shown that the application of this definition to models can be affected by model mean biases; i.e., more frequent SSW appears to occur in models with a weaker climatological polar vortex. In order to overcome this deficiency, a tendency-based definition, which is not sensitive to the model mean bias, is proposed and applied to the multi-model data sets archived for the Coupled Model Intercomparison Projection phase 5 (CMIP5). In this definition, SSW-like events are defined by sufficiently strong vortex deceleration. This approach removes a linear relationship between the SSW frequency and intensity of climatological polar vortex for both the low-top and high-top CMIP5 models. Instead, the resulting SSW frequency is strongly correlated with wave activity at 100 hPa. The two definitions detect quantitatively different SSW in terms of lower stratospheric wave activity and downward propagation of stratospheric anomalies to the troposphere. However, in both definitions, the high-top models generally exhibit more frequent SSW than the low-top models. Moreover, a hint of more frequent SSW in a warm climate is commonly found.

  10. Sudden birth of entanglement between two atoms in a double JC model

    Institute of Scientific and Technical Information of China (English)

    Mingdi Du; Maofa Fang; Xiang Liu

    2009-01-01

    Sudden birth of entanglement between two initially separate atoms interacting with two entangled photons in a double JC model is investigated,arid the influences of different atomic initial states on entanglement among atoms are discussed.The results show that sudden birth of entanglement can occur when the two atoms are initially in excited states.

  11. The sudden Birth and sudden Death of thermal fidelity in a two-qubit XY model

    CERN Document Server

    Qin, Li-Guo; Jiang, Ying; Zhang, Hong-Biao

    2011-01-01

    We study the energy level crossings of the states and thermal fidelity for a two-qubit XY model in the presence of a transverse and inhomogeneous magnetic field. It is shown clearly the effects of the anisotropic factor of the magnetic field through the contour figures of energy level crossing in two subspaces, the isotropy subspace and anisotropy subspace. We calculate the quantum fidelity between the system and the ground state to which the results show the strong effect of the anisotropic factor again. In addition, making use of the transition of Yangian generators in the tensor product space, we study the evolution of the thermal fidelity after the transition. The potential applications of Yangian algebra, as a switch to turn on or off the fidelity, are proposed.

  12. Sudden Deafness

    Science.gov (United States)

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Sudden Deafness On this page: What is sudden deafness? What ... I find additional information about SSHL? What is sudden deafness? Sudden sensorineural hearing loss (SSHL), commonly known as ...

  13. Mode specificity and product energy disposal in unimolecular reactions: insights from the sudden vector projection model.

    Science.gov (United States)

    Li, Jun; Guo, Hua

    2014-04-03

    A simple model is proposed to predict mode specificity and product energy disposal in unimolecular dissociation reactions. This so-called Sudden Vector Projection (SVP) model quantifies the coupling of a reactant or product mode with the reaction coordinate at the transition state by projecting the corresponding normal mode vector onto the imaginary frequency mode at the saddle point. Due to the sudden assumption, SVP predictions for mode specificity are expected to be valid only when the reactant molecule has weak intermodal coupling. On the other hand, the sudden limit is generally satisfied for its predictions of product energy disposal in unimolecular reactions with a tight barrier. The SVP model is applied to several prototypical systems and the agreement with available experimental and theoretical results is satisfactory.

  14. Cardiac conduction system anomalies and sudden cardiac death: insights from murine models

    Directory of Open Access Journals (Sweden)

    Amelia Eva Aranega

    2012-06-01

    Full Text Available The cardiac conduction system (CCS is a series of specialized tissues in the heart responsible for the initiation and co-ordination of the heartbeat. Alterations in the CCS, especially the His-Purkinje system, have been identified as an important player in the generation of lethal arrhythmias. Unstable arrhythmias secondary to channelopathies highly increase the risk of sudden cardiac death (SCD. Sudden cardiac death is a major contributor to mortality in industrialized nations, and most cases of SCD in the young are related to inherited ion channel diseases. In this review we examine how murine transgenic models have contributed to understanding that a broad variety of cardiac arrhythmias involve the cardiac specialized conduction system and may lead to sudden cardiac death.

  15. Challenges in the Brent field: Implementing depressurization

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, S.H.; Wilson, P.M. [Shell U.K. E and P (United Kingdom)

    1998-02-01

    The Brent field, 116 miles northeast of Lerwick, Shetlands Islands had 3.8 billion STB oil originally in place and 7.5 Tcf gas originally in place. The field was discovered in July 1971 and brought on production 5 years later, on 11 November 1976. The field reached a maximum annual average oil production of 410,000 B/D in 1984. Since the mid-1980`s, oil production has been declining, but substantial gas reserves remain dissolved in the residual and bypassed oil because of the high solution-gas/oil ratio. Since the outset of field development, ideas have been conceived to recover these large gas volumes and to optimize oil recovery further. As oil production started to decline, a wide range of improved- and enhanced-oil-recovery (EOR) options were systematically evaluated. The full-length paper presents details of the depressurization plan, early results, and a number of related issues and how they are being managed with references to several papers that describe these issues in greater detail.

  16. The Effect of Velocity on the Extinction Behavior of a Diffusion Flame during Transient Depressurization

    Science.gov (United States)

    Goldmeer, Jeffrey S.; Urban, David L.; Tien, James

    1999-01-01

    Current fire suppression plans for the International Space Station include the use of venting (depressurization) as a method for extinguishing a fire. Until recently this process had only been examined as part of a material flammability experiment performed on Skylab in the early 1970's. Due to the low initial pressure (0.35 Atm) and high oxygen concentration (65%), the Skylab experimental results are not applicable for understanding the effects of venting on a fire in a space station environment (21%O2, 1 Atm). Recent research examined the extinction behavior of a diffusion flame over a polymethyl methacrylate (PMMA) cylinder during a transient depressurization in low-gravity. The numerical model was used to examine extinction limits as a function of depressurization rate, forced flow velocity, and initial solid phase temperature. The experimental and numerically predicted extinction data indicated that as the solid phase temperature increased the pressure required to extinguish the flame decreased. The numerical model was also used to examine conditions not obtainable in the low-gravity experiments. From these simulations, a series of extinction boundaries were generated that showed a region of increased flammability existed at a forced flow of 10 cm/s. Analysis of these extinction boundaries indicated that they were quasi-steady in nature, and that the final extinction conditions were independent of the transient process. The velocity range in the previous study was limited and thus the results did not examine the effects of velocities less than 1 cm/s or greater than 20 cm/s. This study utilized low-gravity experiments performed on NASA's Reduced-gravity Research Aircraft Laboratory and numerical simulations to examine conditions applicable to the Space Station environment. This paper extends the analysis of the previous study to a comprehensive examination of the effect of increased velocity on extinction behavior and extinction limits during a transient

  17. Sudden spreading of infections in an epidemic model with a finite seed fraction

    CERN Document Server

    Hasegawa, Takehisa

    2016-01-01

    We study a simple case of the susceptible-weakened-infected-removed model in regular random graphs in a situation where an epidemic starts from a finite fraction of initially infected nodes (seeds). Previous studies have shown that, assuming a single seed, this model exhibits a kind of discontinuous transition at a certain value of infection rate. Performing Monte Carlo simulations and evaluating approximate master equations, we find that the present model has two critical infection rates with a finite seed fraction. At the first critical rate the system shows a percolation transition of clusters composed of removed nodes, and at the second critical rate, which is larger than the first one, a giant cluster suddenly grows and the order parameter jumps even though it has been already rising. Numerical evaluation of the master equations shows that such sudden epidemic spreading does occur if the degree of the underlying network is large and the seed fraction is small.

  18. Simulation of gas production from hydrate reservoir by the combination of warm water flooding and depressurization

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Gas production from hydrate reservoir by the combination of warm water flooding and depressurization is proposed,which can overcome the deficiency of single production method.Based on the combination production method,the physical and mathematical models are developed to simulate the hydrate dissociation.The mathematical model can be used to analyze the effects of the flow of multiphase fluid,the kinetic process of hydrate dissociation,the endothermic process of hydrate dissociation,ice-water phase equilibrium,the convection and conduction on the hydrate dissociation and gas and water production.The mechanism of gas production by the combination of warm water flooding and depressurization is revealed by the numerical simulation.The evolutions of such physical variables as pressure,temperature,saturations and gas and water rates are analyzed.Numerical results show that under certain conditions the combination method has the advantage of longer stable period of high gas rate than the single producing method.

  19. FUZZY MODEL FOR TWO-DIMENSIONAL RIVER WATER QUALITY SIMULATION UNDER SUDDEN POLLUTANTS DISCHARGED

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the fuzziness and impreciseness of water environmental system, the fuzzy arithmetic was used to simulate the fuzzy and imprecise relations in modeling river water quality. By defining the parameters of water quality model as symmetrical triangular fuzzy numbers, a two-dimensional fuzzy water quality model for sudden pollutant discharge is established. From the fuzzy model, the pollutant concentrations, corresponding to the specified confidence level of α, can be obtained by means of the α-cut technique and arithmetic operations of triangular fuzzy numbers. Study results reveal that it is feasible in theory and reliable on calculation applying triangular fuzzy numbers to the simulation of river water quality.

  20. Depressurization amorphization of single-crystal boron carbide.

    Science.gov (United States)

    Yan, X Q; Tang, Z; Zhang, L; Guo, J J; Jin, C Q; Zhang, Y; Goto, T; McCauley, J W; Chen, M W

    2009-02-20

    We report depressurization amorphization of single-crystal boron carbide (B4C) investigated by in situ high-pressure Raman spectroscopy. It was found that localized amorphization of B4C takes place during unloading from high pressures, and nonhydrostatic stresses play a critical role in the high-pressure phase transition. First-principles molecular dynamics simulations reveal that the depressurization amorphization results from pressure-induced irreversible bending of C-B-C atomic chains cross-linking 12 atom icosahedra at the rhombohedral vertices.

  1. PLANE SURFACE SUDDENLY SET IN MOTION IN A VISCOELASTIC FLUID WITH FRACTIONAL MAXWELL MODEL

    Institute of Scientific and Technical Information of China (English)

    谭文长; 徐明瑜

    2002-01-01

    The fractional calculus approach in the constitutive relationship model of viscoelastic fluid is introduced. The flow near a wall suddenly set in motion is studied for a non-Newtonian viscoelastic fluid with the fractional Maxwell model. Exact solutions of velocity and stress are obtained by using the discrete inverse Laplace transform of the sequential fractional derivatives. It is found that the effect of the fractional orders in the constitutive relationship on the flow field is significant. The results show that for small times there are appreciable viscoelastic effects on the shear stress at the plate, for large times the viscoelastic effects become weak.

  2. Plane surface suddenly set in motion in a viscoelastic fluid with fractional Maxwell model

    Science.gov (United States)

    Wenchang, Tan; Mingyu, Xu

    2002-08-01

    The fractional calculus approach in the constitutive relationship model of viscoelastic fluid is introduced. The flow near a wall suddenly set in motion is studied for a non-Newtonian viscoelastic fluid with the fractional Maxwell model. Exact solutions of velocity and stress are obtained by using the discrete inverse Laplace transform of the sequential fractional derivatives. It is found that the effect of the fractional orders in the constitutive relationship on the flow field is significant. The results show that for small times there are appreciable viscoelastic effects on the shear stress at the plate, for large times the viscoelastic effects become weak.

  3. The sudden vector projection model for reactivity: mode specificity and bond selectivity made simple.

    Science.gov (United States)

    Guo, Hua; Jiang, Bin

    2014-12-16

    CONSPECTUS: Mode specificity is defined by the differences in reactivity due to excitations in various reactant modes, while bond selectivity refers to selective bond breaking in a reaction. These phenomena not only shed light on reaction dynamics but also open the door for laser control of reactions. The existence of mode specificity and bond selectivity in a reaction indicates that not all forms of energy are equivalent in promoting the reactivity, thus defying a statistical treatment. They also allow the enhancement of reactivity and control product branching ratio. As a result, they are of central importance in chemistry. This Account discusses recent advances in our understanding of these nonstatistical phenomena. In particular, the newly proposed sudden vector projection (SVP) model and its applications are reviewed. The SVP model is based on the premise that the collision in many direct reactions is much faster than intramolecular vibrational energy redistribution in the reactants. In such a sudden limit, the coupling of a reactant mode with the reaction coordinate at the transition state, which dictates its ability to promote the reaction, is approximately quantified by the projection of the former onto the latter. The SVP model can be considered as a generalization of the venerable Polanyi's rules, which are based on the location of the barrier. The SVP model is instead based on properties of the saddle point and as a result capable of treating the translational, rotational, and multiple vibrational modes in reactions involving polyatomic reactants. In case of surface reactions, the involvement of surface atoms can also be examined. Taking advantage of microscopic reversibility, the SVP model has also been used to predict product energy disposal in reactions. This simple yet powerful rule of thumb has been successfully demonstrated in many reactions including uni- and bimolecular reactions in the gas phase and gas-surface reactions. The success of the SVP

  4. Numerical Simulation of the Depressurization Process of a Natural Gas Hydrate Reservoir: An Attempt at Optimization of Field Operational Factors with Multiple Wells in a Real 3D Geological Model

    Directory of Open Access Journals (Sweden)

    Zhixue Sun

    2016-09-01

    Full Text Available Natural gas hydrates, crystalline solids whose gas molecules are so compressed that they are denser than a typical fluid hydrocarbon, have extensive applications in the areas of climate change and the energy crisis. The hydrate deposit located in the Shenhu Area on the continental slope of the South China Sea is regarded as the most promising target for gas hydrate exploration in China. Samples taken at drilling site SH2 have indicated a high abundance of methane hydrate reserves in clay sediments. In the last few decades, with its relatively low energy cost, the depressurization gas recovery method has been generally regarded as technically feasible and the most promising one. For the purpose of a better acquaintance with the feasible field operational factors and processes which control the production behavior of a real 3D geological CH4-hydrate deposit, it is urgent to figure out the effects of the parameters such as well type, well spacing, bottom hole pressure, and perforation intervals on methane recovery. One years’ numerical simulation results show that under the condition of 3000 kPa constant bottom hole pressure, 1000 m well spacing, perforation in higher intervals and with one horizontal well, the daily peak gas rate can reach 4325.02 m3 and the cumulative gas volume is 1.291 × 106 m3. What’s more, some new knowledge and its explanation of the curve tendency and evolution for the production process are provided. Technically, one factor at a time design (OFAT and an orthogonal design were used in the simulation to investigate which factors dominate the productivity ability and which is the most sensitive one. The results indicated that the order of effects of the factors on gas yield was perforation interval > bottom hole pressure > well spacing.

  5. Performing a Launch Depressurization Test on an Inflatable Space Habitat

    Science.gov (United States)

    Martin, Patrick J.; Van Velzer, Paul

    2014-01-01

    In July, 2014 JPL's Environmental Test Laboratory successfully performed a launch depressurization test on an inflatable space habitat proposed to be installed on the International Space Station. The inflatable habitat is to be launched in the SpaceX Dragon Trunk. During the launch, the unpressurized Dragon Trunk will rapidly change from ground level atmospheric pressure to the vacuum of space. Since the inflatable habitat is tightly folded during launch with multiple layers of bladder, Kevlar fabric sections, and micro-meteoroid shielding, it was not possible to analyze or simulate how the residual air pockets would behave during the launch. If the inflatable habitat does not vent adequately and expands, it could rupture the payload bay of the launch vehicle. A launch depressurization test was chosen as the best way to qualify the inflatable habitat. When stowed, the inflatable habitat measured approximately 241 cm (95 inches) in diameter by 152 cm (60 inches) high and weighed close to 1361 kg (3,000 pounds). Two vacuum chambers connected by a large vacuum line were used to perform this test. The inflatable habitat was mounted in the smaller chamber, which was 396 cm (13 feet) in diameter and 1128 cm (37 feet) high. The larger chamber, which was 823 cm (27 feet) in diameter and 2,591 cm (85 feet) high, was rough pumped and used as a vacuum reservoir. A two stage axial type compressor and ten Stokes vacuum pumps were also used during the depressurization. Opening a butterfly valve on the vacuum line, at the smaller chamber, was manually controlled so that the smaller chamber's depressurization rate matched the launch pressure profile.

  6. The simulation of gas production from oceanic gas hydrate reservoir by the combination of ocean surface warm water flooding with depressurization

    Institute of Scientific and Technical Information of China (English)

    Hao Yang; Yu-Hu Bai; Qing-Ping Li

    2012-01-01

    A new method is proposed to produce gas from oceanic gas hydrate reservoir by combining the ocean surface warm water flooding with depressurization which can efficiently utilize the synthetic effects of thermal,salt and depressurization on gas hydrate dissociation.The method has the advantage of high efficiency,low cost and enhanced safety.Based on the proposed conceptual method,the physical and mathematical models are established,in which the effects of the flow of multiphase fluid,the kinetic process of hydrate dissociation,the endothermic process of hydrate dissociation,ice-water phase equilibrium,salt inhibition,dispersion,convection and conduction on the hydrate dissociation and gas and water production are considered.The gas and water rates,formation pressure for the combination method are compared with that of the single depressurization,which is referred to the method in which only depressurization is used.The results show that the combination method can remedy the deficiency of individual producing methods.It has the advantage of longer stable period of high gas rate than the single depressurization.It can also reduce the geologic hazard caused by the formation deformation due to the maintaining of the formation pressure by injected ocean warm water.

  7. Dynamic solution of vessel depressuring; Simulacao dinamica de despressurizacao em vasos

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Marco Tulio; Silva Netto, Rafael [Chemtech Servicos de Engenharia e Software Ltda., Rio de Janeiro, RJ (Brazil); Aires, Joyce Stone S. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    Vessel depressuring is an important phenomenon on chemical and petrochemical processes, specially those related to oil and gas exploration, production and processing. The correct modeling of this phenomenon and prediction of the temperatures, mass and thermal rates involved is essential to the adequate design of the equipment, materials specification and safety standards assurance. To fulfill these requirements, we developed a method to simulate the phenomenon of depressuring. In this approach, the dynamic process is discretized along time, being calculated at each interval the conditions inside the vessel, material flow and heat exchanges with the environment, through mass and energy balances and thermodynamic equilibrium calculation. The method can include different models to calculate heat exchanges and flow through the relief valve, and new methods can be incorporated if necessary. The efficiency of the method was verified by comparing its results with the ones obtained by market-leaders process simulators, when it was proved the robustness of the method and precision of the results. To increase its flexibility of use, the method was incorporated to the PETROBRAS Process Simulator - PETROX (PETROBRAS, 2004), in a development made by Chemtech under a contract with PETROBRAS and already used in large scale by PETROBRAS to simulate its process units. (author)

  8. Extended sudden approximation model for high-energy nucleon removal reactions

    Energy Technology Data Exchange (ETDEWEB)

    Carstoiu, F.; Sauvan, E.; Orr, N.A. [Caen Univ., Lab. de Physique Corpusculaire, Institut des Sciences de la Matiere et du Rayonnement, IN2P3-CNRS ISMRA, 14 (France); Carstoiu, F. [IFIN-HH, Bucharest-Magurele (Romania); Bonaccorso, A. [Istituto Nazionale di Fisica Nucleare, Pisa (Italy)

    2004-04-01

    A model based on the sudden approximation has been developed to describe high energy single nucleon removal reactions. Within this approach, which takes as its starting point the formalism of Hansen, the nucleon-removal cross section and the full 3-dimensional momentum distributions of the core fragments including absorption, diffraction, Coulomb and nuclear-Coulomb interference amplitudes, have been calculated. The Coulomb breakup has been treated to all orders for the dipole interaction. The model has been compared to experimental data for a range of light, neutron-rich psd-shell nuclei. Good agreement was found for both the inclusive cross sections and momentum distributions. In the case of {sup 17}C, comparison is also made with the results of calculations using the transfer-to-the-continuum model. The calculated 3-dimensional momentum distributions exhibit longitudinal and transverse momentum components that are strongly coupled by the reaction for s-wave states, whilst no such effect is apparent for d-waves. Incomplete detection of transverse momenta arising from limited experimental acceptances thus leads to a narrowing of the longitudinal distributions for nuclei with significant s-wave valence neutron configurations, as confirmed by the data. Asymmetries in the longitudinal momentum distributions attributed to diffractive dissociation are also explored. (authors)

  9. Jugular valve function and petrosal sinuses pressure: a computational model applied to sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Mirko Tessari

    2017-04-01

    Full Text Available Reports of extra-cranial venous outflow disturbances have recently been linked to sudden sensorineural hearing loss (SSNHL. Aims of the present study are: i to quantify, with mathematical model, the impact of jugular valve function on the pressure of the superior and inferior petrosal sinuses (SPS, IPS and the main auricolar veins; ii to verify the feasibility of the application of mathematical model in the clinical setting in terms of consistency respect to the usual measures of SSNHL outcome. Extra-cranial venous outflow and post analysis were respectively blindly assessed by echo colour-Doppler (ECD and a validated mathematical model for the human circulation. The pilot study was conducted on 1 healthy control and in a group of 4 patients with different outcome of SSNHL. The main finding was the significant increased pressure calculated in the SPS and IPS of patients with ipsilateral jugular obstruction due to not mobile valve leaflets (6.55 mmHg, respect to the other subjects without extracranial complete obstruction (6.01 mmHg, P=0.0006. Moreover, we demonstrated an inverted correlation between the extrapolated pressure values in the SPS/IPS and the mean flow measured in the correspondent internal jugular vein (r= –0.87773; r-squared= 0.7697; P=0.0009. The proposed mathematical model can be applied to venous extra-cranial ECD investigation in order to derive novel clinical information on the drainage of the inner ear. Such clinical information seems to provide coherent parameters potentially capable to drive the prognosis. This innovative approach was proven to be feasible by the present pilot investigation and warrants further studies with an increased sample of patients.

  10. Laboratory modelling of sudden coal-methane outbursts with a Hopkinson bar

    Energy Technology Data Exchange (ETDEWEB)

    Toth, J.; Szabo-Lakatos, J.; Pindel, Z. (Hungarian Academy of Sciences, Miskolc-Egyetemvaros (Hungary). Research Laboratory for Mining Chemistry)

    1990-01-01

    The physicochemical aspects of sudden coal-methane outbursts have been studied, with the help of a modified Hopkinson pressure bar and the following important phenomena have been observed: (1) the desorption of methane takes place instantly after impact. (2) The amount of gas desorbed is greater by two-three orders of magnitude than that before the impact. (3) The higher hydrocarbon components (C{sub 2}-C{sub 4}) appear in the desorbed gas. (4) The coal samples become crushed. (5) A linear relationship exists between the kinetic energy of the striker bar and the amount of methane desorbed. (6) An exponential relationship exists between the amount of methane desorbed and the rate of desorption before the impact. (7) The amount of gas desorbed is independent of the nature of the mechanical effects (a single, or repeated small impacts). These phenomena pertain to black coals containing methane in the manner of a solid solution in the micropores, the closed pores and in the molecular lattice. A semi-quantitative model of an equilibrium established in the methane-coal system has been proposed to explain this. 5 refs., 10 figs.

  11. Nonlinear modeling and dynamic analysis of a hydro-turbine governing system in the process of sudden load increase transient

    Science.gov (United States)

    Li, Huanhuan; Chen, Diyi; Zhang, Hao; Wang, Feifei; Ba, Duoduo

    2016-12-01

    In order to study the nonlinear dynamic behaviors of a hydro-turbine governing system in the process of sudden load increase transient, we establish a novel nonlinear dynamic model of the hydro-turbine governing system which considers the elastic water-hammer model of the penstock and the second-order model of the generator. The six nonlinear dynamic transfer coefficients of the hydro-turbine are innovatively proposed by utilizing internal characteristics and analyzing the change laws of the characteristic parameters of the hydro-turbine governing system. Moreover, from the point of view of engineering, the nonlinear dynamic behaviors of the above system are exhaustively investigated based on bifurcation diagrams and time waveforms. More importantly, all of the above analyses supply theoretical basis for allowing a hydropower station to maintain a stable operation in the process of sudden load increase transient.

  12. Numerical Investigation of the Transient Behavior of a Hot Gas Duct under Rapid Depressurization

    Directory of Open Access Journals (Sweden)

    JingBao Liu

    2016-01-01

    Full Text Available A hot gas duct is an indispensable component for the nuclear-process heat applications of the Very-High-Temperature Reactor (VHTR, which has to fulfill three requirements: to withstand high temperature, high pressure, and large pressure transient. In this paper, numerical investigation of pressure transient is performed for a hot gas duct under rapid depressurization. System depressurization imposes an imploding pressure differential on the internal structural elements of a hot gas duct, the structural integrity of which is susceptible to being damaged. Pressure differential and its imposed duration, which are two key factors to evaluate the damage severity of a hot gas duct under depressurization, are examined in regard to depressurization rate and insulation packing tightness. It is revealed that depressurization rate is a decisive parameter for controlling the pressure differential and its duration, whereas insulating-packing tightness has little effect on them.

  13. A Model of a Sudden-Death Field-Goal Football Game as a Sequential Duel

    OpenAIRE

    Siddhartha Sahi; Martin Shubik

    1985-01-01

    This paper introduces a highly simplified version of "sudden-death" scoring. The basic game is as follows. With equal probability the teams toss to see who gets the ball. The team with the ball can either run or try to kick a field goal. The first team to score wins the game.

  14. 78 FR 41684 - Special Conditions: Embraer S.A. Model EMB-550 Airplanes, Sudden Engine Stoppage

    Science.gov (United States)

    2013-07-11

    ...-engine installations, the engine mounts, pylons, and adjacent supporting airframe structure must be... are to be multiplied by a factor of 1.0 when applied to engine mounts and pylons, and multiplied by a..., Sudden Engine Stoppage AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final...

  15. Statistical and Modeling Techniques for Studying the Sudden Infant Death Syndrome

    Science.gov (United States)

    Lindsey, Helen L.

    1976-01-01

    The intention of this research is to contribute additional data, hopefully bearing on the solution to some of the problems and indirectly, the cause(s) of Sudden Infant Death Syndrome, and to present ideas for consideration for future SIDS research. (Author/RK)

  16. Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Kneafsey, T.; Moridis, G.J.

    2011-01-15

    A preserved sample of hydrate-bearing sandstone from the Mount Elbert Test Well was dissociated by depressurization while monitoring the internal temperature of the sample in two locations and the density changes at high spatial resolution using x-ray CT scanning. The sample contained two distinct regions having different porosity and grain size distributions. The hydrate dissociation occurred initially throughout the sample as a result of depressing the pressure below the stability pressure. This initial stage reduced the temperature to the equilibrium point, which was maintained above the ice point. After that, dissociation occurred from the outside in as a result of heat transfer from the controlled temperature bath surrounding the pressure vessel. Numerical modeling of the test using TOUGH+HYDRATE yielded a gas production curve that closely matches the experimentally measured curve.

  17. A Study of Invasive RCS Depressurization under SBO/SBLOCA in OPR1000-IPSS

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jihee; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Chang, Soon Heung [Handong Global University, Pohang (Korea, Republic of)

    2015-05-15

    After the Fukushima accident, nuclear power plants (NPPs) need to retain abilities to deal with multiple beyond design basis accidents (BDBAs). For that, several supplementary safety systems for current NPPs in operation have been suggested. The Integrated Passive Safety System (IPSS) is one of the supplements operated by natural phenomena. This paper suggests invasive RCS depressurization methods on a primary circuit to overcome the capacity limitation. So that water through PSIS inject to the depressurized primary circuit for core cooling, finally to attain the ultimate goal, preventing the core damage. ADS4 was suggested to increase depressurization capacity of a primary loop to operate IPSS-PSIS under SBO/SBLOCA. From simulations, ADS4 showed successful depressurization for SBLOCA with fast RCS depressurization in early phase of LOCA. However, all suggested cases were proved a capability of PSIS-IPSS to deal with SB/MBLOCA under SBO with certain operational timing of SDS and ADS4. The code results proved importance of coolant injection during early phase of LOCA. For ADS4 opening cases, the most successful cool-down was conducted when ADS4 opened at 80 bar and 120 bar for 1 and 2 inches of LOCA, respectively. 3. However, the sequential operation of SDS and ADS4 has higher probability to offer sufficient RCS depressurization after the early phase of LOCA. Based on ADS4 actuation time, depressurization strategies for IPSS-PSIS should be defined as a further study.

  18. Mathematical Model and Simulation of Gas Hydrate Reservoir Decomposition by Depressurization Modèle mathématique et simulation de dépressurisation et de décompression d’un réservoir d’hydrates de méthane

    Directory of Open Access Journals (Sweden)

    Zhao J.

    2012-05-01

    Full Text Available The numerical model for the depressurization of methane hydrates in a confined reservoir is presented based on mass conservation in porous media, incorporating multiphase flow theory and kinetics of gas hydrate dissociation. The universal implicit difference method is adopted, and the corresponding computer program is developed. During the production of the hydrate reservoir, distribution and the physical changes are analyzed and the gas hydrate dissociation and gas production law are studied from the computation. A numerical simulation shows that the reservoir pressure is descending slowly, which benefits the stabilization of the reservoir and inevitably decreases the efficiency in the production of gas hydrates in the depressurizing process. The gas production rate is controlled by the well pressure. The results are presented to show how this model may be used to estimate a lower downhole pressure of the well for hydrate recovery and how these results depend on reservoir and hydrate properties. Le modèle numérique présenté ici simule la dépressurisation d’hydrates de méthane dans un réservoir confiné; il se base sur le principe de conservation de la masse en milieu poreux, en intégrant la théorie de l’écoulement polyphasique et la cinétique de dissociation des hydrates de méthane. La méthode implicite et universelle des différences finies est utilisée et le programme informatique qui s’y rapporte est développé. Lors de l’exploitation du réservoir d’hydrates de méthane, la répartition et les changements physiques sont analysés et les lois sur la dissociation des hydrates de méthane et la production de gaz sont étudiées à partir des calculs. Une simulation numérique montre que la pression dans le réservoir diminue lentement, ce qui permet au réservoir de se stabiliser et diminue inévitablement le rendement de l’exploitation d’hydrates de méthane lors du processus de dépressurisation. Le rythme de

  19. The Temperature of the Dimethylhydrazine Drops Moving in the Atmosphere after Depressurization of the Fuel Tank Rockets

    Directory of Open Access Journals (Sweden)

    Bulba Elena

    2016-01-01

    Full Text Available This work includes the results of the numerical modeling of temperature changes process of the dimethylhydrazine (DMH drops, taking into account the radial temperature gradient in the air after the depressurization of the fuel compartments rockets at high altitude. There is formulated a mathematical model describing the process of DMH drops thermal state modifying when it's moving to the Earth's surface. There is the evaluation of the influence of the characteristic size of heptyl drops on the temperature distribution. It's established that the temperatures of the small size droplets practically completely coincide with the distribution of temperature in the atmosphere at altitudes of up to 40 kilometers.

  20. Animal models for assessment of infection and inflammation: contributions to elucidating the pathophysiology of sudden infant death syndrome (SIDS

    Directory of Open Access Journals (Sweden)

    Jane eBlood-Siegfried

    2015-03-01

    Full Text Available Sudden Infant Death Syndrome (SIDS is still not well understood. It is a diagnosis of exclusion following the sudden and unexpected death of an infant. There are numerous theories about the etiology of SIDS but the exact cause or causes have never been pinpointed.Examination of theoretical pathologies might only be possible in animal models. Development of these models requires consideration of the genetic, developmental and environmental risk factors associated with SIDS, as they need to explain how the risk factors could contribute to the cause of death. These models were initially developed in common laboratory animals to test various hypotheses to explain these infant deaths - guinea pig, piglet, mouse, neonatal rabbit and neonatal rat. Currently there are growing numbers of researchers using genetically altered animals to examine specific areas of interest. This review describes the different systems and models developed to examine the diverse hypotheses for the cause of SIDS and their potential for defining a causal mechanism or mechanisms.

  1. Droplet Impact on a Heated Surface under a Depressurized Environment

    Science.gov (United States)

    Hatakenaka, Ryuta; Tagawa, Yoshiyuki

    2016-11-01

    Behavior of a water droplet of the diameter 1-3mm impacting on a heated surface under depressurized environment (100kPa -1kPa) has been studied. A syringe pump for droplet generation and a heated plate are set into a transparent acrylic vacuum chamber. The internal pressure of the chamber is automatically controlled at a target pressure with a rotary pump, a pressure transducer, and an electrical valve. A silicon wafer of the thickness 0.28 mm is mounted on the heater plate, whose temperature is directly measured by attaching a thermocouple on the backside. The droplet behavior is captured using a high-speed camera in a direction perpendicular to droplet velocity. Some unique behaviors of droplet are observed by decreasing the environmental pressure, which are considered to be due to two basic elements: Enhancement of evaporation due to the lowered saturation temperature, and shortage of pneumatic spring effect between the droplet and heated wall due to the lowered pressure of the air.

  2. An Observation and Modeling Study of a Sudden Impulse Event for the Coupled Magnetosphere-Ionosphere System

    Science.gov (United States)

    Ozturk, Dogacan; Slavin, A. James; Zou, Shasha

    2016-07-01

    The dayside response of the Magnetosphere-Ionosphere system to an increment in the solar wind pressure and its propagation towards the magnetotail is investigated. The pressure enhancement compresses the magnetosphere front and this compression creates shear Alfven waves that lead to intensified Field-Aligned Currents (FACs). We use the University of Michigan global magnetohydrodynamic (MHD) code, Block Adaptive Tree Solar-wind Roe Upwind Scheme (BATS'R'US) to model the response of the Magnetosphere-Ionosphere system. The measurements from Advanced Composition Explorer (ACE) are used for the upstream solar wind values to drive the model. We use the Rice Convection Model (RCM) for the Inner Magnetosphere and improve the treatment of ionospheric conductivity of the system. We compare the FAC patterns and intensities of the model with the high-resolution data from Active Magnetosphere and Polar Electrodynamics Response Experiment (AMPERE). We also study the magnetic perturbation signatures of the event obtained from selected ground-based magnetometers and associated output for the magnetometer station from the model. In addition, we investigate the propagation of the sudden impulse through the tail to understand the wave characteristics. Using the multipoint observations of Magnetospheric MultiScale (MMS) mission and other magnetospheric spacecraft we determine the wave propagation speed and compare it with the model results to better understand the response mechanism. By using the magnetic field measurements from MMS we also study how the magnetic topology and the boundary changes in the magnetotail as the sudden impulse (SI) signatures propagate through the tail.

  3. Extinguishment of a Diffusion Flame Over a PMMA Cylinder by Depressurization in Reduced-Gravity

    Science.gov (United States)

    Goldmeer, Jeffrey Scott

    1996-01-01

    Extinction of a diffusion flame burning over horizontal PMMA (Polymethyl methacrylate) cylinders in low-gravity was examined experimentally and via numerical simulations. Low-gravity conditions were obtained using the NASA Lewis Research Center's reduced-gravity aircraft. The effects of velocity and pressure on the visible flame were examined. The flammability of the burning solid was examined as a function of pressure and the solid-phase centerline temperature. As the solid temperature increased, the extinction pressure decreased, and with a centerline temperature of 525 K, the flame was sustained to 0.1 atmospheres before extinguishing. The numerical simulation iteratively coupled a two-dimensional quasi-steady, gas-phase model with a transient solid-phase model which included conductive heat transfer and surface regression. This model employed an energy balance at the gas/solid interface that included the energy conducted by the gas-phase to the gas/solid interface, Arrhenius pyrolysis kinetics, surface radiation, and the energy conducted into the solid. The ratio of the solid and gas-phase conductive fluxes Phi was a boundary condition for the gas-phase model at the solid-surface. Initial simulations modeled conditions similar to the low-gravity experiments and predicted low-pressure extinction limits consistent with the experimental limits. Other simulations examined the effects of velocity, depressurization rate and Phi on extinction.

  4. Mudstone depressurization behaviour in an open pit coal mine, Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Marchand, G.; Waterhouse, J. [Golder Associates, West Perth, WA (Australia); Crisostomo, J. [PT Adaro Indonesia, Jakarta (Indonesia)

    2010-07-01

    Mining activities in the Tutupan mine in Indonesia began in the mid-1990s. The open pit mine's coal seams are interbedded with fine-grained sandstones, mudstones, and carbonaceous mudstones. Slope stability analyses at the pit have integrated hydrogeology with geotechnical engineering analyses to optimize slope designs and reduce the risk of slope failure. This paper discussed the impact of mining and dewatering on mudstone depressurization. Sensors were placed at key points in the mine to obtain data related to the mudstone units. Reductions in pore pressure occurred as a result of groundwater flow away from the observed zones, increases in porosity, and increases in total porosity caused by an expansion of the rock mass as a result of drainage and hydrostatic unloading. Mudstone pore pressure trends with time were interpreted by determining the thickness of the mudstone unit, the presence or absence of known thin sandstone beds, unloading from overhead mining activities, and the position of the mudstone within the sedimentary sequence. The study showed that unloading activities have a significant impact on pore pressure in thick mudstone units, regardless of the depth, thickness, or properties of the unit. Pore pressure within high wall mudstone units typically decreased to values equivalent to the elevation of the unit where it was exposed to dips in a high wall. The dewatering of sandstone units in low walls caused a decline in pore pressure within the thick mudstone units located beneath the sandstones. Differences in primary permeabilities were attributed to greater fracturing in deeper and stronger rock units. 3 refs., 4 figs.

  5. Uni- and multivariate models for investigating potential prognostic factors in idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Lionello, Marco; Staffieri, Claudia; Breda, Stefano; Turato, Chiara; Giacomelli, Luciano; Magnavita, Paola; de Filippis, Cosimo; Staffieri, Alberto; Marioni, Gino

    2015-08-01

    With a worldwide incidence estimated at 8-15 per 100,000 population a year, idiopathic sudden sensorineural hearing loss (ISSHL) is a common clinical finding for otologists. There is a shortage of information on the clinical factors capable of predicting hearing recovery and response to therapy. The aim of the present study was to retrospectively investigate the prognostic value of clinical variables in relation to hearing recovery, in a cohort of 117 consecutive patients with ISSHL. Clinical parameters (signs, symptoms, comorbidities and treatments) and audiometric data were analyzed with univariate and multivariate statistical approaches for prognostic purposes to identify any correlation with hearing recovery, also expressed according to the Wilson criteria. Univariate analysis showed that age and hypertension were significantly related to hearing outcome (p = 0.004 and p = 0.015, respectively). Elderly patients and those with hypertension were at higher risk of experiencing no hearing recovery (OR = 3.25 and OR = 2.89, respectively). Age was an independent prognostic factor on multivariate analysis (p = 0.007). Tinnitus as a presenting symptom showed a trend towards an association with hearing recovery (p = 0.07). The treatment regimen, the time elapsing between the onset of symptoms and the start of therapy (p = 0.34), and the duration of the treatment (p = 0.83) were unrelated to recovery on univariate analysis. Among the parameters considered, only age was significantly and independently related to hearing outcome. There is a need for well-designed, randomized clinical trials to enable an evidence-based protocol to be developed for the treatment of ISSHL.

  6. Analysis of design and operational effects of filtered containment venting on depressurization and fission product release

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Woon; Seol, Wook-Cheol; Kim, Jisu [Dongguk Univ., Gyeongbuk (Korea, Republic of)

    2017-03-15

    Effects of design and operational parameters of filtered containment venting system during a specified containment depressurization and relative aero sol release amount are analyzed. The analyses is performed by using the MAAP4 code for the APR1400 reactor. Major results uniquely identified from the analyses can be noted as following: Even though containment depressurization is accelerated as the pipe size increases, the venting system solution is also depleted earlier. Elapsed times to reach lower end pressure of 2 bar are nearly identical regardless of the vent initiation pressure and thus early venting is not much beneficial than late venting. Stroke time of the isolation valves has no effect on the depressurization performance and thus slow opening is beneficial for load reduction from the vent effluent.

  7. Vision Loss, Sudden

    Science.gov (United States)

    ... of age-related macular degeneration. Spotlight on Aging: Vision Loss in Older People Most commonly, vision loss ... Some Causes and Features of Sudden Loss of Vision Cause Common Features* Tests Sudden loss of vision ...

  8. Sudden Stratospheric Warming Compendium

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sudden Stratospheric Warming Compendium (SSWC) data set documents the stratospheric, tropospheric, and surface climate impacts of sudden stratospheric warmings. This...

  9. Numerical modelling of VLF radio wave propagation through earth-ionosphere waveguide and its application to sudden ionospheric disturbances

    CERN Document Server

    Pal, Sujay

    2015-01-01

    In this thesis, we theoretically predict the normal characteristics of Very Low Frequency (3~30 kHz) radio wave propagation through Earth-ionosphere waveguide corresponding to normal behavior of the D-region ionosphere. We took the VLF narrow band data from the receivers of Indian Centre for Space Physics (ICSP) to validate our models. Detection of sudden ionospheric disturbances (SIDs) are common to all the measurements. We apply our theoretical models to infer the D-region characteristics and to reproduce the observed VLF signal behavior corresponding to such SIDs. We develop a code based on ray theory to simulate the diurnal behavior of VLF signals over short propagation paths (2000~3000 km). The diurnal variation from this code are comparable to the variation obtained from a more general Long Wave Propagation Capability (LWPC) code which is based on mode theory approach. We simulate the observational results obtained during the Total Solar Eclipse of July 22, 2009 in India. We also report and simulate a h...

  10. Physical property changes in hydrate-bearingsediment due to depressurization and subsequent repressurization

    Energy Technology Data Exchange (ETDEWEB)

    Kneafsey, Timothy; Waite, W.F.; Kneafsey, T.J.; Winters, W.J.; Mason, D.H.

    2008-06-01

    Physical property measurements of sediment cores containing natural gas hydrate are typically performed on material exposed at least briefly to non-in situ conditions during recovery. To examine effects of a brief excursion from the gas-hydrate stability field, as can occur when pressure cores are transferred to pressurized storage vessels, we measured physical properties on laboratory-formed sand packs containing methane hydrate and methane pore gas. After depressurizing samples to atmospheric pressure, we repressurized them into the methane-hydrate stability field and remeasured their physical properties. Thermal conductivity, shear strength, acoustic compressional and shear wave amplitudes and speeds are compared between the original and depressurized/repressurized samples. X-ray computed tomography (CT) images track how the gas-hydrate distribution changes in the hydrate-cemented sands due to the depressurization/repressurization process. Because depressurization-induced property changes can be substantial and are not easily predicted, particularly in water-saturated, hydrate-bearing sediment, maintaining pressure and temperature conditions throughout the core recovery and measurement process is critical for using laboratory measurements to estimate in situ properties.

  11. Depressurization and two-phase flow of water containing high levels of dissolved nitrogen gas

    Science.gov (United States)

    Simoneau, R. J.

    1981-01-01

    Depressurization of water containing various concentrations of dissolved nitrogen gas was studied. In a nonflow depressurization experiment, water with very high nitrogen content was depressurized at rates from 0.09 to 0.50 MPa per second and a metastable behavior which was a strong function of the depressurization rate was observed. Flow experiments were performed in an axisymmetric, converging diverging nozzle, a two dimensional, converging nozzle with glass sidewalls, and a sharp edge orifice. The converging diverging nozzle exhibited choked flow behavior even at nitrogen concentration levels as low as 4 percent of the saturation level. The flow rates were independent of concentration level. Flow in the two dimensional, converging, visual nozzle appeared to have a sufficient pressure drop at the throat to cause nitrogen to come out of solution, but choking occurred further downstream. The orifice flow motion pictures showed considerable oscillation downstream of the orifice and parallel to the flow. Nitrogen bubbles appeared in the flow at back pressures as high as 3.28 MPa, and the level at which bubbles were no longer visible was a function of nitrogen concentration.

  12. RCGVS design improvement and depressurization capability tests for Ulchin nuclear power plant units 3 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Kang Sik; Seong, Ho Je; Jeong, Won Sang; Seo, Jong Tae; Lee, Sang Keun [Korea Power Engineering Company, Inc., Seoul (Korea, Republic of); Lim, Keun Hyo; Choi, Kwon Sik; Oh, Chul Sung [Korea Electric Power Cooperation, Taejon (Korea, Republic of)

    1998-12-31

    The Reactor Coolant Gas Vent System(RCGVS) design for Ulchin Nuclear Power Plant Units 3 and 4 (UCN 3 and 4) has been improved from the Yonggwang Nuclear Power Plant Units 3 and 4 (YGN 3 and 4) based on the evaluation results for depressurization capability tests performed at YGN 3 and 4. There has been a series of plant safety analyses for Natural Circulation Cooldown(NCC) event and thermo-dynamic analyses with RELAP5 code for the steam blowdown phenomena in order to optimize the orifice size of UCN 3 and 4 RCGVS. Based on these analyses results, the RCGVS orifics size for UCN 3 and 4 has been reduced to 9/32 inch from the 11/32 inch for YGN 3 and 4. The depressurization capability tests, which were performed at UCN 3 in order to verify the FSAR NCC analysis results, show that the RCGVS depressurization rates are being within the acceptable ranges. Therefore, it is concluded that the orificed flow path of UCN 3 and 4 RCGVS is adequately designed, and can provide the safety-grade depressurization capability required for a safe plant operation. 6 refs., 5 figs., 1 tab. (Author)

  13. [New guidelines for reducing the risk of sudden infant death. "Triple risk model" provide the basis for prevention].

    Science.gov (United States)

    Wennergren, Göran

    The Swedish National Board of Health and Welfare has presented new advice to reduce the risk of Sudden Infant Death Syndrome, SIDS, supplemented with factual material for health personnel. The advice state: 1) The infant should sleep on its back, 2) parents should refrain from nicotine, 3) the infant’s face should be kept free, overheating avoided and movements not restrained, 4) the safest place to sleep for an infant under three months is in its own cot, 5) breast-feed if possible, and 6) pacifier (dummy) can be used when the infant is going to sleep. Apparent life-threatening events in the maternity ward are discussed. In early breast-feeding attempts, it should be checked that breathing is free to avoid suffocation accidents. The best hypothesis of SIDS pathogenesis seems to be offered by the triple risk model, suggesting that an interaction of different risk factors leads to SIDS: 1) a critical developmental period, 2) a vulnerable infant and 3) an exogenous stressor (extrinsic risk factor).

  14. Hydro-geomechanical behaviour of gas-hydrate bearing soils during gas production through depressurization and CO2 injection

    Science.gov (United States)

    Deusner, C.; Gupta, S.; Kossel, E.; Bigalke, N.; Haeckel, M.

    2015-12-01

    Results from recent field trials suggest that natural gas could be produced from marine gas hydrate reservoirs at compatible yields and rates. It appears, from a current perspective, that gas production would essentially be based on depressurization and, when facing suitable conditions, be assisted by local thermal stimulation or gas hydrate conversion after injection of CO2-rich fluids. Both field trials, onshore in the Alaska permafrost and in the Nankai Trough offshore Japan, were accompanied by different technical issues, the most striking problems resulting from un-predicted geomechanical behaviour, sediment destabilization and catastrophic sand production. So far, there is a lack of experimental data which could help to understand relevant mechanisms and triggers for potential soil failure in gas hydrate production, to guide model development for simulation of soil behaviour in large-scale production, and to identify processes which drive or, further, mitigate sand production. We use high-pressure flow-through systems in combination with different online and in situ monitoring tools (e.g. Raman microscopy, MRI) to simulate relevant gas hydrate production scenarios. Key components for soil mechanical studies are triaxial systems with ERT (Electric resistivity tomography) and high-resolution local strain analysis. Sand production control and management is studied in a novel hollow-cylinder-type triaxial setup with a miniaturized borehole which allows fluid and particle transport at different fluid injection and flow conditions. Further, the development of a large-scale high-pressure flow-through triaxial test system equipped with μ-CT is ongoing. We will present results from high-pressure flow-through experiments on gas production through depressurization and injection of CO2-rich fluids. Experimental data are used to develop and parametrize numerical models which can simulate coupled process dynamics during gas-hydrate formation and gas production.

  15. Numerical studies of hydrate dissociation and gas production behavior in porous media during depressurization process

    Institute of Scientific and Technical Information of China (English)

    Xuke Ruan; Mingjun Yang; Yongchen Song; Haifeng Liang; Yanghui Li

    2012-01-01

    In this study,a numerical model is developed to investigate the hydrate dissociation and gas production in porous media by depressurization.A series of simulation runs are conducted to study the impacts of permeability characteristics,including permeability reduction exponent,absolute permeability,hydrate accumulation habits and hydrate saturation,sand average grain size and irreducible water saturation.The effects of the distribution of hydrate in porous media are examined by adapting conceptual models of hydrate accumulation habits into simulations to govern the evolution of permeability with hydrate decomposition,which is also compared with the conventional reservoir permeability model,i.e.Corey model.The simulations show that the hydrate dissociation rate increases with the decrease of permeability reduction exponent,hydrate saturation and the sand average grain size.Compared with the conceptual models of hydrate accumulation habits,our simulations indicate that Corey model overpredicts the gas production and the performance of hydrate coating models is superior to that of hydrate filling models in gas production,which behavior does follow by the order of capillary coating>pore coating>pore filling>capillary filling.From the analysis of t1/2,some interesting results are suggested as follows:(1) there is a "switch" value (the "switch" absolute permeability) for laboratory-scale hydrate dissociation in porous media,the absolute permeability has almost no influence on the gas production behavior when the permeability exceeds the "switch" value.In this study,the "switch" value of absolute permeability can be estimated to be between 10 and 50 md.(2) An optimum value of initial effective water saturation Sw,e exists where hydrate dissociation rate reaches the maximum and the optimum value largely coincides with the value of irreducible water saturation Swr,e.For the case of Sw,e<Swr,e,or Sw,e>Swr,e,there are different control mechanisms dominating the

  16. Accelerated activation of SOCE current in myotubes from two mouse models of anesthetic- and heat-induced sudden death.

    Directory of Open Access Journals (Sweden)

    Viktor Yarotskyy

    Full Text Available Store-operated calcium entry (SOCE channels play an important role in Ca(2+ signaling. Recently, excessive SOCE was proposed to play a central role in the pathogenesis of malignant hyperthermia (MH, a pharmacogenic disorder of skeletal muscle. We tested this hypothesis by characterizing SOCE current (ISkCRAC magnitude, voltage dependence, and rate of activation in myotubes derived from two mouse models of anesthetic- and heat-induced sudden death: 1 type 1 ryanodine receptor (RyR1 knock-in mice (Y524S/+ and 2 calsequestrin 1 and 2 double knock-out (dCasq-null mice. ISkCRAC voltage dependence and magnitude at -80 mV were not significantly different in myotubes derived from wild type (WT, Y524S/+ and dCasq-null mice. However, the rate of ISkCRAC activation upon repetitive depolarization was significantly faster at room temperature in myotubes from Y524S/+ and dCasq-null mice. In addition, the maximum rate of ISkCRAC activation in dCasq-null myotubes was also faster than WT at more physiological temperatures (35-37°C. Azumolene (50 µM, a more water-soluble analog of dantrolene that is used to reverse MH crises, failed to alter ISkCRAC density or rate of activation. Together, these results indicate that while an increased rate of ISkCRAC activation is a common characteristic of myotubes derived from Y524S/+ and dCasq-null mice and that the protective effects of azumolene are not due to a direct inhibition of SOCE channels.

  17. Structure and Evolution of Singular Vectors in a Global Forecast Model during the January 2009 Stratospheric Sudden Warming

    Science.gov (United States)

    Eckermann, S. D.; Reynolds, C. A.; Coy, L.

    2012-12-01

    Singular vectors (SV) of a global forecast model are computed over deep domains of the Northern Hemisphere throughout January 2009 to investigate rapidly-growing perturbations and troposphere-stratosphere predictability. In early-to-mid January, when the stratospheric vortex was relatively undisturbed, the fastest growing stratospheric SV perturbations form initially on the equatorward flanks of the vortex jet as isolated tilted packet-like structures that grow rapidly in energy and horizontal scale, propagate into the core of the vortex jet and self-organize into quasi-barotropic Rossby-wave trains. From 22-28 January, a period characterized by a major wave-2 stratospheric sudden warming (SSW), stratospheric SV structure and evolution change dramatically. SV energy growth increases and the leading stratospheric SV (SV1) assumes an hemispheric geopotential height structure closely resembling a negative anomaly in the northern annular mode (NAM). Forecasts with atmospheric initial conditions perturbed with initial ±SV1 perturbations produce rapid growth of this hemispheric annular perturbation, which in turn either enhances or suppresses the forecast strength of the SSW. Relative to a control forecast, +SV1-perturbed forecasts increase the strength of the forecast SSW, as reflected in the rate and degree of vortex splitting, the magnitude of forced mean stratospheric easterlies and the descent rate of easterly shear zones, leading to mean easterlies in the high-latitude troposphere and stratosphere after 3-4 days. Conversely, -SV1-perturbed forecasts weaken and then halt the warming, yielding a minor SSW with mean westerlies throughout the high-latitude troposphere and stratosphere after ~4 days.This forecast SSW sensitivity to growing ±SV1 perturbations arises in each case as a positive feedback driven by large reinforcing changes in planetary-wave Eliassen-Palm (EP) fluxes, with +SV1-perturbed forecasts increasing poleward EP fluxes and -SV1-perturbed forecasts

  18. An Animal Model of Sudden Onset Sensorineural Hearing Loss with Vestibular Function Disturbances Induced By Mitochondrial Toxin

    Institute of Scientific and Technical Information of China (English)

    ZOU Jing; ZHANG Ya; PYYKK(O) Ilmari; WU Hao

    2006-01-01

    To establish an animal model of sudden onset sensorineural hearing loss (SSNHL) to study its mechanisms. Materials and methods The inner ear was exposed to 3-nitropropionic acid at 0.5 mol/L (3-NP (H)) and 0.3 mol/L (3-NP (L)) through the round window membrane for 30 minutes in 50 male guinea pigs. Thresholds of auditory brainstem responses (ABR) were established before the treatment and retested at 4 hours, 1 day, 3 days and 6 days following 3-NP exposure. Control animals were treated with phosphate buffered saline (PBS) and their ABRs were retested at 4 hours and 1 day after the treatment. Animals were monitored for nystagmus and postural signs of vestibular dysfunction, using a digital video camera, following the treatment procedure. Specimens were taken at 12 hours, 1 day, 3 days and 7 days following 3-NP (H) exposure and embedded in JB4 for light microscopy observation. Results ABRs were lost in all animals tested at 4 hours following 3-NP (H) exposure. The rate of complete ABR loss decreased as post-treatment test time increased. ABRs were lost in 80% (4/5) of the animals at 1 day after exposure to 3-NP (L). Spontaneous horizontal nystagmus with a fast phase away from the treated ear developed in all 3-NP (H)-treated animals and in 20 % (1/5) of the animals exposed to 3-NP (L), except for the one treated bilaterally. Various degree of postural disturbances consistent with unilateral vestibular dysfunction, such as spontaneous barrel rolling towards the exposure side while walking, were seen in all animals exposed to 3-NP(H) and 40% (2/5) of animals exposed to 3-NP(L), except for the one animal treated bilaterally, which showed no signs of imbalance. Both nystagmus and postural disturbances resolved in 2 days following 3-NP exposure. Histological study showed temporary edema tin the organ or Corti, Claudius cells and the inner sulcus cells 3 days after 3-NP (H) treatment. Enlargement of intercellular space in the spiral prominence was first noticed at 12 hours

  19. Assessment of Severe Accident Depressurization Valve Activation Strategy for Chinese Improved 1000 MWe PWR

    Directory of Open Access Journals (Sweden)

    Ge Shao

    2013-01-01

    Full Text Available To prevent HPME and DCH, SADV is proposed to be added to the pressurizer for Chinese improved 1000 MWe PWR NPP with the reference of EPR design. Rapid depressurization capability is assessed using the mechanical analytical code. Three typical severe accident sequences of TMLB’, SBLOCA, and LOFW are selected. It shows that with activation of the SADV the RCS pressure is low enough to prevent HPME and DCH. Natural circulation at upper RPV and hot leg is considered for the rapid depressurization capacity analysis. The result shows that natural circulation phenomenon results in heat transfer from the core to the pipes in RCS which may cause the creep rupture of pipes in RCS and delays the severe accident progression. Different SADV valve areas are investigated to the influence of depressurization of RCS. Analysis shows that the introduction of SADV with right valve area will delay progression of core degradation to RPV failure. Valve area is to be optimized since smaller SADV area will reduce its effect and too large valve area will lead to excessive loss of water inventory in RCS and makes core degradation progression to RPV failure faster without additional core cooling water sources.

  20. Physical property changes in hydrate-bearing sediment due to depressurization and subsequent repressurization

    Science.gov (United States)

    Waite, W.F.; Kneafsey, T.J.; Winters, W.J.; Mason, D.H.

    2008-01-01

    Physical property measurements of sediment cores containing natural gas hydrate are typically performed on material exposed, at least briefly, to non-in situ conditions during recovery. To examine the effects of a brief excursion from the gas-hydrate stability field, as can occur when pressure cores are transferred to pressurized storage vessels, we measured physical properties on laboratory-formed sand packs containing methane hydrate and methane pore gas. After depressurizing samples to atmospheric pressure, we repressurized them into the methane-hydrate stability field and remeasured their physical properties. Thermal conductivity, shear strength, acoustic compressional and shear wave amplitudes, and speeds of the original and depressurized/repressurized samples are compared. X-ray computed tomography images track how the gas-hydrate distribution changes in the hydrate-cemented sands owing to the depressurizaton/repressurization process. Because depressurization-induced property changes can be substantial and are not easily predicted, particularly in water-saturated, hydrate-bearing sediment, maintaining pressure and temperature conditions throughout the core recovery and measurement process is critical for using laboratory measurements to estimate in situ properties.

  1. Sudden Infant Death Syndrome.

    Science.gov (United States)

    Barnett, Henry L.; And Others

    There is a growing body of evidence that Sudden Infant Death Syndrome (SIDS) victims are not completely normal and healthy, as was once believed. A variety of new information from several disciplines strongly suggests that the infant who dies suddenly and unexpectedly may do so because of subtle developmental, neurologic, cardiorespiratory, and…

  2. Sudden cardiac death

    Directory of Open Access Journals (Sweden)

    Neeraj Parakh

    2015-01-01

    Full Text Available Sudden cardiac death is one of the most common cause of mortality worldwide. Despite significant advances in the medical science, there is little improvement in the sudden cardiac death related mortality. Coronary artery disease is the most common etiology behind sudden cardiac death, in the above 40 years population. Even in the apparently healthy population, there is a small percentage of patients dying from sudden cardiac death. Given the large denominator, this small percentage contributes to the largest burden of sudden cardiac death. Identification of this at risk group among the apparently healthy individual is a great challenge for the medical fraternity. This article looks into the causes and methods of preventing SCD and at some of the Indian data. Details of Brugada syndrome, Long QT syndrome, Genetics of SCD are discussed. Recent guidelines on many of these causes are summarised.

  3. A mouse model to study the link between hypoxia, long QT interval and sudden infant death syndrome.

    Science.gov (United States)

    Neary, Marianne T; Mohun, Timothy J; Breckenridge, Ross A

    2013-03-01

    The pathology of sudden infant death syndrome (SIDS) is poorly understood. Many risk factors, including hypoxia, have been identified. Prolongation of the ECG QTc interval is associated with elevated risk of SIDS but its aetiology in most cases remains unknown. We have characterised ECG changes in the newborn mouse in the hours and days following birth. There was a steady increase in heart rate alongside significant decreases in QTc interval, QRS duration and QTc dispersion over the first 10 postnatal days. Birth into hypoxia (10% FiO2) prevented electrocardiac maturation, downregulated cardiac ion-channel expression and led to neonatal death. We found that risk of death decreased with increasing age of exposure to hypoxia. Genetic elevation of cardiac hypoxia-signalling after birth in αMHC-Cre::VHL(fl/fl) mice also prevented electrocardiographic maturation, leading to arrhythmia and death before weaning. Immunohistochemistry and western blotting revealed internalisation and dephosphorylation of Connexin43. We conclude that increased ambient oxygen concentration after birth drives maturation of the cardiac electrical conduction system, failure of which leads to aberrant ion channel and Connexin43 expression and predisposes to arrhythmia and sudden death. This is consistent with known risk factors of SIDS and provides a link between neonatal hypoxia, ECG abnormalities and sudden death.

  4. Sudden Cardiac Death

    Directory of Open Access Journals (Sweden)

    Yipsy María Gutiérrez Báez

    2015-09-01

    Full Text Available Since the second half of the twentieth century, dying suddenly due to heart-related problems has become the main health issue in all countries where infectious diseases are not prevalent. Sudden death from cardiac causes is an important global health problem. Major databases were searched for the leading causes of sudden cardiac death. It has been demonstrated that there is a group of hereditary diseases with structural alterations or without apparent organic cause that explains many cases of sudden death in young people, whether related or not to physical exertion. Certain population groups are at higher risk for this disease. They are relatively easy to identify and can be the target of primary prevention measures.

  5. Geomagnetic Storm Sudden Commencements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Storm Sudden Commencements (ssc) 1868 to present: STORM1 and STORM2 Lists: (Some text here is taken from the International Association of Geomagnetism and Aeronomy...

  6. Sudden Ionospheric Disturbances (SID)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sudden ionospheric disturbances (SID) are caused by solar flare enhanced X-rays in the 1 to 10 angstrom range. Solar flares can produce large increases of ionization...

  7. Communication: Ro-vibrational control of chemical reactivity in H+CH₄→ H₂+CH₃: full-dimensional quantum dynamics calculations and a sudden model.

    Science.gov (United States)

    Welsch, Ralph; Manthe, Uwe

    2014-08-07

    The mode-selective chemistry of the title reaction is studied by full-dimensional quantum dynamics simulation on an accurate ab initio potential energy surface for vanishing total angular momentum. Using a rigorous transition state based approach and multi-configurational time-dependent Hartree wave packet propagation, initial state-selected reaction probabilities for many ro-vibrational states of methane are calculated. The theoretical results are compared with experimental trends seen in reactions of methane. An intuitive interpretation of the ro-vibrational control of the chemical reactivity provided by a sudden model based on the quantum transition state concept is discussed.

  8. Effect of Acute Intermittent CPAP Depressurization during Sleep in Obese Patients.

    Directory of Open Access Journals (Sweden)

    Jonathan C Jun

    Full Text Available Obstructive Sleep Apnea (OSA describes intermittent collapse of the airway during sleep, for which continuous positive airway pressure (CPAP is often prescribed for treatment. Prior studies suggest that discontinuation of CPAP leads to a gradual, rather than immediate return of baseline severity of OSA. The objective of this study was to determine the extent of OSA recurrence during short intervals of CPAP depressurization during sleep.Nine obese (BMI = 40.4 ± 3.5 subjects with severe OSA (AHI = 88.9 ± 6.8 adherent to CPAP were studied during one night in the sleep laboratory. Nasal CPAP was delivered at therapeutic (11.1 ± 0.6 cm H20 or atmospheric pressure, in alternating fashion for 1-hour periods during the night. We compared sleep architecture and metrics of OSA during CPAP-on and CPAP-off periods.8/9 subjects tolerated CPAP withdrawal. The average AHI during CPAP-on and CPAP-off periods was 3.6 ± 0.6 and 15.8 ± 3.6 respectively (p<0.05. The average 3% ODI during CPAP-on and CPAP-off was 4.7 ± 2 and 20.4 ± 4.7 respectively (p<0.05. CPAP depressurization also induced more awake (p<0.05 and stage N1 (p<0.01 sleep, and less stage REM (p<0.05 with a trend towards decreased stage N3 (p = 0.064.Acute intermittent depressurization of CPAP during sleep led to deterioration of sleep architecture but only partial re-emergence of OSA. These observations suggest carryover effects of CPAP.

  9. Sudden hearing loss in children.

    Science.gov (United States)

    Ječmenica, Jovana; Bajec-Opančina, Aleksandra

    2014-08-01

    Sudden sensorineural hearing loss (SSHL) is defined as a unilateral or bilateral sensorineural hearing loss with at least 30 dB decrease in threshold in 3 contiguous test frequencies occurring over 72 hours or less. It is very rare in children. Sudden hearing loss is a symptom that suggests that there is a problem in the inner ear, surrounding structures, or the whole organism. The etiology and development of this disorder are still not fully understood. The literature contains numerous models of the pathogenesis of SSHL, with childhood SSHL having certain peculiarities. In practical terms, the multifactorial nature of SSHL is important in the choice of diagnostic methods and treatment methods. It is important to determine the cause and effect relationship between the underlying disease and hearing loss.

  10. SIMULATION OF SUDDEN-EXPANSION AND SWIRLING GAS-PARTICLE FLOWS USING A TWO-FLUID PARTICLE-WALL COLLISION MODEL WITH CONSIDERATION OF THE WALL ROUGHNESS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lixing; ZHANG Xia

    2004-01-01

    A two-fluid particle-wall collision model with consideration of wall roughness is proposed. It takes into account the effects of the friction, restitution and in particular the wall roughness,and hence the redistribution of Reynolds stress in different directions, the absorption of turbulent energy from the mean motion and the attenuation of particle motion by the wall. The proposed model is used to simulate sudden-expansion and swirling gas-particle flows and is validated by comparing with experimental results. The results show that the proposed model gives better results than those obtained by the presently used zero-gradient condition. Hence, it is suggested that the proposed model should be used as the wall boundary condition for the particle phase in place of the presently used boundary condition.

  11. Non-equilibrium simulation of CH4 production through the depressurization method from gas hydrate reservoirs

    Science.gov (United States)

    Qorbani, Khadijeh; Kvamme, Bjørn

    2016-04-01

    as non-equilibrium processes under local constraint of mass and heat fluxes. In this work, we have extended RCB by adding another route for dissociation or reformation of CH4-hydrate towards CH4 into the aqueous phase and water. CH4-hydrate formation and dissociation is resolved by looking at supersaturation and undersaturation with respect to thermodynamics variables. Hydrate instability due to undersaturation of CH4 in the contacting water phase is also considered. A complete non-equilibrium thermodynamic package, developed in-house, was combined with RCB to account for competing phase transitions by considering the minimization of Gibb's free energy. The energy differences were calculated from variations in chemical potentials of hydrate and hydrate formers. Mass transport, heat transport and non-equilibrium thermodynamic effects were implemented through classical nucleation theory to model the kinetic rate of hydrate phase transitions. To illustrate our implementations we ran simulations covering time-spans in the order of hundred years. CH4 production was modelled using the depressurization method, where we employed the Messoyakha field data. We discuss our implementations, as well as results obtained from simulations utilizing our modifications.

  12. Punctuated Equilibrium in Statistical Models of Generalized Coevolutionary Resilience: How Sudden Ecosystem Transitions Can Entrain Both Phenotype Expression and Darwinian Selection

    Science.gov (United States)

    Wallace, Rodrick; Wallace, Deborah

    We argue that mesoscale ecosystem resilience shifts akin to sudden phase transitions in physical systems can entrain similarly punctuated events of gene expression on more rapid time scales, and, in part through such means, slower changes induced by selection pressure, triggering punctuated equilibrium Darwinian evolutionary transitions on geologic time scales. The approach reduces ecosystem, gene expression, and Darwinian genetic dynamics to a least common denominator of information sources interacting by crosstalk at markedly differing rates. Pettini's 'topological hypothesis', via a homology between information source uncertainty and free energy density, generates a regression-like class of statistical models of sudden coevolutionary phase transition based on the Rate Distortion and Shannon-McMillan Theorems of information theory which links all three levels. A mathematical treatment of Holling's extended keystone hypothesis regarding the particular role of mesoscale phenomena in entraining both slower and faster dynamical structures produces the result. A main theme is the necessity of a cognitive paradigm for gene expression, mirroring I. Cohen's cognitive approach to immune function. Invocation of the necessary conditions imposed by the asymptotic limit theorems of communication theory enables us to penetrate one layer more deeply before needing to impose an empirically-derived phenomenological system of 'Onsager relation' recursive coevolutionary stochastic differential equations. Extending the development to second order via a large deviations argument permits modeling the influence of human cultural structures on ecosystems as 'farming'.

  13. Analysis of Long-Term Station Blackout without automatic depressurization at Peach Bottom using MELCOR (Version 1.8)

    Energy Technology Data Exchange (ETDEWEB)

    Madni, I.K. [Brookhaven National Lab., Upton, NY (United States)

    1994-05-01

    This report documents the results from MELCOR calculations of the Long-Term Station Blackout Accident Sequence, with failure to depressurize the reactor vessel, at the Peach Bottom (BWR Mark I) plant, and presents comparisons with Source Term Code Package calculations of the same sequence. STCP has calculated the transient out to 13.5, hours after core uncovery. Most of the MELCOR calculations presented have been carried out to between 15 and 16.7 hours after core uncovery. The results include the release of source terms to the environment. The results of several sensitivity calculations with MELCOR are also presented, which explore the impact of varying user-input modeling and timestep control parameters on the accident progression and release of source terms to the environment. Most of the calculations documented here were performed in FY1990 using MELCOR Version 1.8BC. However, the appendices also document the results of more recent calculations performed in FY1991 using MELCOR versions 1.8CZ and 1.8DNX.

  14. Experimental Investigation Evaporation of Liquid Mixture Droplets during Depressurization into Air Stream

    Science.gov (United States)

    Liu, L.; Bi, Q. C.; Terekhov, Victor I.; Shishkin, Nikolay E.

    2010-03-01

    The objective of this study is to develop experimental method to study the evaporation process of liquid mixture droplets during depressurization and into air stream. During the experiment, a droplet was suspended on a thermocouple; an infrared thermal imager was used to measure the droplet surface temperature transition. Saltwater droplets were used to investigate the evaporation process during depressurization, and volatile liquid mixtures of ethanol, methanol and acetone in water were applied to experimentally research the evaporation into air stream. According to the results, the composition and concentration has a complex influence on the evaporation rate and the temperature transition. With an increase in the share of more volatile component, the evaporation rate increases. While, a higher salt concentration in water results in a lower evaporation rate. The shape variation of saltwater droplet also depends on the mass concentration in solution, whether it is higher or lower than the eutectic point (22.4%). The results provide important insight into the complex heat and mass transfer of liquid mixture during evaporation.

  15. Experimental Study on Mechanism of Depressurizing Dissociation of Methane Hydrate under Saturated Pore Fluid

    Institute of Scientific and Technical Information of China (English)

    Sun Youhong; Su Kai; Guo Wei; Li Bing; Jia Rui

    2016-01-01

    Sediment-hosted hydrate reservoir often contains saturated pore lfuid, which changes the heat transfer and mass transfer characteristics of the hydrate reservoir. The exploitation of hydrate under saturated pore lfuid using depressurization is simulated experimentally to investigate the inlfuence of particle size of porous media, dissociation temperature, pressure drop and injected lfuid type on gas production behavior. Homogeneous methane hydrate was ifrstly formed in frozen quartz sand. With the formed hydrate sample, hydrate dissociation experiments by depressurization were conducted. The test results showed that the gas production rate of hydrate under saturated pore lfuid was substantially inlfuenced by the particle size, the pressure drop and the injected lfuid type, while it was inlfuenced little by the dissociation temperature. The hydrate dissociates faster under larger pressure drop and in the presence of smaller porous media within the experimental region. The dissociation rate increases with an increasing lfuid salinity in the initial stage, while it decreases in the later stage. The increase of gas diffusion resistance resulted from ionic hydration atmosphere in saturated chloride solution impeded the dissociation of hydrate. It can be solved by increasing the pressure drop and decreasing the lfuid salinity in the process of gas recovery from hydrate reservoir.

  16. [Sudden onset diplopia].

    Science.gov (United States)

    Besch, D; Schuettauf, F

    2013-09-01

    Sudden onset diplopia may occur secondary to something as simple as uncorrected refractive error or as complicated as brainstem disorders in conjunction with other symptoms. Therefore, all complaints of diplopia must be a cause for concern. Ophthalmologists have to determine if diplopia is the first sign of a systemic or neurological disorder, which needs to be referred to a specialist or can be managed by the practitioner. In this paper the importance of the case history, primary diagnostic options, the indications for supplementary testing with computed tomography (CT) or magnetic resonance imaging (MRI) as well as treatment options when a patient complains of sudden onset diplopia are discussed.

  17. EXPERIMENTAL STUDIES ON SWIRLING AND RECIRCULATING TWO-PHASE FLOW FIELD IN A COLD MODEL OF DUAL-INLET SUDDEN-EXPANSION COMBUSTOR

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The axial and tangential velocities of gas and particle phases and particle concentration for turbulent swirling and recirculating gas-particle (simulating gas-droplet) flows in a cold model of a dual-inlet sudden-expansion combustor with partially tangential central tubes, proposed by the present authors, were measured by using a 2-D LDV system and a laser optic fiber system combined with a sampling probe. The results show that there are both gas and particle strongly reverse flows and swirling flows in the head part of the combustor. The velocity slip between gas and particle phases is remarkable. The particle concentration is higher near the wall and lower near the axis. There are two peaks in the concentration profiles near the inlet tubes. The above-obtained flow characteristics are favorable to ignition, flame stabilization and combustion. The results can also be used to validate the numerical modeling.

  18. Sudden Hearing Loss.

    Science.gov (United States)

    Vaughan, John C.

    1997-01-01

    Patients with a sudden dramatic decline in hearing usually require rapid diagnosis and treatment. Unfortunately, the treatment of this condition continues to be controversial and an exact etiology in most cases has been inconclusive. Nevertheless, physicians have reached a consensus regarding several broad principles, which are presented in this…

  19. Sudden Hearing Loss.

    Science.gov (United States)

    Vaughan, John C.

    1997-01-01

    Patients with a sudden dramatic decline in hearing usually require rapid diagnosis and treatment. Unfortunately, the treatment of this condition continues to be controversial and an exact etiology in most cases has been inconclusive. Nevertheless, physicians have reached a consensus regarding several broad principles, which are presented in this…

  20. Control factors of coalbed methane well depressurization cone under drainage well network in southern Qinshui basin%沁水盆地南部煤层气井网排采压降漏斗的控制因素

    Institute of Scientific and Technical Information of China (English)

    刘世奇; 桑树勋; 李梦溪; 刘会虎; 王立龙

    2012-01-01

    Under the condition of drainage by well network, this study established a mathematic model of coalbed methane (CBM) well depressurization cone from drainage stage to initial pro- duction-gas stage on the basis of the radial fluid flow theory, superposition principle of pres- sure drop, and the production data of 15 CBM wells in southern Qinshui basin. Visualization of the depressurization cone was realized using Matlab. Based on the analysis of the shape and e- volution characteristics of depressurization cones, this study proposes a defining method for single well depressurization cone and evaluation methodology for superposition degree of composite depressurization cone, and discusses the control factors of the shape for depressurization cone. The results show that: from drainage stage to initial production-gas stage, when the per- meability is bigger than 8 X 10.3 ptm2 , ground water level is higher than 680 m and daily aver- age displacement is less than 3 ma/d, daily average gas production of CBM wells are usually larger than 250 mS/d, the ratio of flush-flow radius to depth of depressurization cone is gener- ally less than 40, and the flush-flow radius is relatively small, accompanied by a rise in decrea- sing amplitude of pressure, and the depressurization cone belongs to the first type; when the permeability is bigger than 8 × 10-3μm2 , ground water level is lower than 680 m and daily av- erage displacement is less than 3 ma/d, daily average gas production of CBM wells are usually less than 250 ma/d and the ratio of flush-flow radius to depth of depressurization cone is gener- ally more than 40, and the flush-flow radius is relatively big, replaced by a drop in decreasing amplitude of pressure, and this depressurization cone belongs to the second type; the ratio of maximum radius of superposed area to well spacing is higher, the degree of superposition improves, the area of superposition increases, and the decrease amplitude of the coal reservoir pressure

  1. Study of the thermospheric and ionospheric response to the 2009 sudden stratospheric warming using TIME-GCM and GSM TIP models: First results

    Science.gov (United States)

    Klimenko, M. V.; Klimenko, V. V.; Bessarab, F. S.; Korenkov, Yu N.; Liu, Hanli; Goncharenko, L. P.; Tolstikov, M. V.

    2015-09-01

    This paper presents a study of mesosphere and low thermosphere influence on ionospheric disturbances during 2009 major sudden stratospheric warming (SSW) event. This period was characterized by extremely low solar and geomagnetic activity. The study was performed using two first principal models: thermosphere-ionosphere-mesosphere electrodynamics general circulation model (TIME-GCM) and global self-consistent model of thermosphere, ionosphere, and protonosphere (GSM TIP). The stratospheric anomalies during SSW event were modeled by specifying the temperature and density perturbations at the lower boundary of the TIME-GCM (30 km altitude) according to data from European Centre for Medium-Range Weather Forecasts. Then TIME-GCM output at 80 km was used as lower boundary conditions for driving GSM TIP model runs. We compare models' results with ground-based ionospheric data at low latitudes obtained by GPS receivers in the American longitudinal sector. GSM TIP simulation predicts the occurrence of the quasi-wave vertical structure in neutral temperature disturbances at 80-200 km altitude, and the positive and negative disturbances in total electron content at low latitude during the 2009 SSW event. According to our model results the formation mechanisms of the low-latitude ionospheric response are the disturbances in the n(O)/n(N2) ratio and thermospheric wind. The change in zonal electric field is key mechanism driving the ionospheric response at low latitudes, but our model results do not completely reproduce the variability in zonal electric fields (vertical plasma drift) at low latitudes.

  2. Numerical simulations of sand production in interbedded hydrate-bearing sediments during depressurization

    Science.gov (United States)

    Uchida, Shun; Lin, Jeen-Shang; Myshakin, Evgeniy; Seol, Yongkoo; Collett, Timothy S.; Boswell, Ray

    2017-01-01

    Geomechanical behavior of hydrate-bearing sediments during gas production is complex, involving changes in hydrate-dependent mechanical properties. When interbedded clay layers are present, the complexity is more pronounced because hydrate dissociation tends to occur preferentially in the sediments adjacent to the clay layers due to clay layers acting as a heat source. This would potentially lead to shearing deformation along the sand/clay contacts and may contribute to solid migration, which hindered past field-scale gas production tests. This paper presents a near-wellbore simulation of sand/clay interbedded hydrate-bearing sediments that have been subjected to depressurization and discusses the effect of clay layers on sand production.

  3. Feasibility study for the adoption of POSRV for KNGR safety depressurization system

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Young Min; Lim, Hong Sik; Song, Jin Ho; Sim, Suk Ku; Park, Jong Kyun

    1999-03-01

    The Korean Next Generation Reactor (KNGR) adopted an advanced design feature of safety depressurization system(SDS) to rapidly de pressurize the reactor coolant system(RCS) in case of beyond design basis events of severe accidents, or a highly unlikely event of a total loss of feedwater (TLOFW) to both steam generators. Two design approaches were considered for the KNGR SDS design. The use of bleed valves similar to those of ABB-CE's system 80+ is design option 1, while in design option 2, the Power Operated Safety Relief valve (POSRV) is considered to provide the combined function of overpressure protection and rapid depressurization. The purpose of this report is to investigate the feasibility of adoption of French SebimPOSRVs for KNGR SDS (design option 2). This report provides the methodology to analyze the TLOFW event with Sebim valves and presents the results of thermal hydraulic analyses using a best-estimate version CEFLASH-4AS/REM for the TLOFW event with feed and bleed. The analyses were performed using a preliminary KNGR design data. For design option 2, if the operator opens two out of the three Sebim valves in conjunction with the four HPSI pumps before a hot leg saturation condition, the decay heat removal and core inventory make-up function can be successfully accomplished. The results of the present investigation demonstrate that the two design options are both feasible to mitigate the consequences of the TLOFW event with a sufficient margin. (Author). 22 refs., 3 tabs., 19 figs.

  4. Enhancement of pigment extraction from B. braunii pretreated using CO2 rapid depressurization

    Directory of Open Access Journals (Sweden)

    Edgar Uquiche

    2016-06-01

    Full Text Available Abstract Extraction of compounds from microalgae requires cell disruption as a pretreatment to increase extraction yield. Botryococcus braunii is a microalga with a significant content of carotenoids and other antioxidant compounds, such as chlorophylls. Cell disruption of B. braunii using CO2 rapid depressurization was studied as a pretreatment for the extraction of carotenoid and chlorophyll pigments. We studied the effect of temperature (21–49 °C and pressure (6–13 MPa during static compression on pigment recovery with supercritical CO2 at 40 °C, 30 MPa and solvent flow of 4.7 L NPT/min. Within the experimental region, the extraction yield of carotenoids and chlorophylls increased by 2.4- and 2.2-fold respectively. Static compression conditions of high pressure and low temperature increased the extraction of carotenoids and especially chlorophylls. We selected 21 °C and 13 MPa as the cell disruption condition, which produced 1.91 g/kg d.s. of carotenoids and 14.03 mg/kg d.s. of chlorophylls. Pretreated microalga gave a 10-fold higher chlorophyll extraction yield compared to the untreated sample. While for carotenoids and tocopherols were 1.25 and 1.14-fold higher, respectively. Additionally, antioxidant activity of pretreated microalga (33.22 mmol TE/kg oil was significantly higher than the value for the untreated samples (29.11 mmol TE/kg oil (p ≤ 0.05. Confocal microscopy images showed morphological differences between micro-colonies with and without disruption treatment, suggesting that partial cell disruption by rapid depressurization improved the extraction of microalga compounds.

  5. Enhancement of pigment extraction from B. braunii pretreated using CO2 rapid depressurization.

    Science.gov (United States)

    Uquiche, Edgar; Antilaf, Ivette; Millao, Sonia

    2016-01-01

    Extraction of compounds from microalgae requires cell disruption as a pretreatment to increase extraction yield. Botryococcus braunii is a microalga with a significant content of carotenoids and other antioxidant compounds, such as chlorophylls. Cell disruption of B. braunii using CO2 rapid depressurization was studied as a pretreatment for the extraction of carotenoid and chlorophyll pigments. We studied the effect of temperature (21-49°C) and pressure (6-13MPa) during static compression on pigment recovery with supercritical CO2 at 40°C, 30MPa and solvent flow of 4.7LNPT/min. Within the experimental region, the extraction yield of carotenoids and chlorophylls increased by 2.4- and 2.2-fold respectively. Static compression conditions of high pressure and low temperature increased the extraction of carotenoids and especially chlorophylls. We selected 21°C and 13MPa as the cell disruption condition, which produced 1.91g/kg d.s. of carotenoids and 14.03mg/kg d.s. of chlorophylls. Pretreated microalga gave a 10-fold higher chlorophyll extraction yield compared to the untreated sample. While for carotenoids and tocopherols were 1.25 and 1.14-fold higher, respectively. Additionally, antioxidant activity of pretreated microalga (33.22mmol TE/kg oil) was significantly higher than the value for the untreated samples (29.11mmol TE/kg oil) (p≤0.05). Confocal microscopy images showed morphological differences between micro-colonies with and without disruption treatment, suggesting that partial cell disruption by rapid depressurization improved the extraction of microalga compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  6. Sudden unexpected death in epilepsy genetics: Molecular diagnostics and prevention.

    Science.gov (United States)

    Goldman, Alica M; Behr, Elijah R; Semsarian, Christopher; Bagnall, Richard D; Sisodiya, Sanjay; Cooper, Paul N

    2016-01-01

    Epidemiologic studies clearly document the public health burden of sudden unexpected death in epilepsy (SUDEP). Clinical and experimental studies have uncovered dynamic cardiorespiratory dysfunction, both interictally and at the time of sudden death due to epilepsy. Genetic analyses in humans and in model systems have facilitated our current molecular understanding of SUDEP. Many discoveries have been informed by progress in the field of sudden cardiac death and sudden infant death syndrome. It is becoming apparent that SUDEP genomic complexity parallels that of sudden cardiac death, and that there is a pauci1ty of analytically useful postmortem material. Because many challenges remain, future progress in SUDEP research, molecular diagnostics, and prevention rests in international, collaborative, and transdisciplinary dialogue in human and experimental translational research of sudden death.

  7. Sudden sensorineural hearing loss.

    Science.gov (United States)

    Stew, B T; Fishpool, S J C; Williams, H

    2012-02-01

    Sudden onset sensorineural hearing loss is a medical emergency that continues to be poorly understood despite being recognized in the literature since 1944 (De Kleyn, 1944). A commonly used criterion to qualify for this diagnosis is a sensorineural hearing loss over three contiguous pure-tone frequencies of 30 dB or more that develops within 72 hours. The vast majority of cases are unilateral and the estimated annual incidence is 20 per 100 000 persons (Nosrati-Zarenoe et al, 2007). A cause for the hearing loss is only identified in up to 10% of cases but 50% of patients will improve spontaneously (Penido et al, 2009).

  8. Sudden Death of Entanglement

    CERN Document Server

    Yu, Ting

    2009-01-01

    A new development in the dynamical behavior of elementary quantum systems is the surprising discovery that correlation between two quantum units of information called qubits can be degraded by environmental noise in a way not seen previously in studies of dissipation. This new route for dissipation attacks quantum entanglement, the essential resource for quantum information as well as the central feature in the Einstein-Podolsky-Rosen so-called paradox and in discussions of the fate of Schr\\"{o}inger's cat. The effect has been labeled ESD, which stands for early-stage disentanglement or, more frequently, entanglement sudden death. We review recent progress in studies focused on this phenomenon.

  9. EXPERIMENTAL STUDIES ON SWIRLING ANDRECIRCULATING TWO-PHASE FLOW FIELD IN A COLD MODEL OF DUAL-INLET SUDDEN-EXPANSION COMBUSTOR

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The dual-inlet liquid-spray-fuelled sudden-expansion combustors are frequently adopted in ramjet engines. The original combustors with swirlers in the inlet tubes frequently suffer from poor ignition, low flame stabilization and poor combustion performance due to insufficient sizes of recirculation zones in the head part of the combustor. There are only very small recirculation zones behind the swirlers. To improve the performance of the combustors, a new configuration is proposed by the authors, in which a small central tube instead of the original swirler is mounted in the inlet tube of the combustor with a tangential angle for creating swirling flows and enlarging the recirculation zones. So, it is expected to know the gas-droplet flow behavior after mounting the central tube. The turbulent swirling and recirculating gas-droplet flows in a dual-inlet sudden-expansion combustor are very complex. In the head part of the combustor there are recirculating flows. In the whole combustor there are swirling flows with a Rankine-vortex structure (solid-body rotation plus free vortex) of tangential velocity profiles. There should be obvious velocity slip between the gas and droplet phases due to the differences in inertia and centrifugal forces. The recirculating and swirling gas-particle flows were previously measured using LDV or PDPA[1~3]. In this paper the experimental studies on two-phase flows were carried out in a cold model of the combustor, and the motion of solid particles is used to simulate that of liquid droplets. The gas and particle (simulating the droplets) velocities were measured using a 2-D LDV system and the particle (simulating the droplet) concentration distribution is measured using a laser optic fiber system and a sampling probe. The purpose of this experimental study is not to simulate the real combustion regime, but to understand the features of the improved two-phase flow field using a central tube in the inlet tube and to provide the data

  10. Modeling Asymmetric Flow of Viscoelastic Fluid in Symmetric Planar Sudden Expansion Geometry Based on User-Defined Function in FLUENT CFD Package

    Directory of Open Access Journals (Sweden)

    Zhi-Ying Zheng

    2013-01-01

    Full Text Available Through embedding an in-house subroutine into FLUENT code by utilizing the functionalization of user-defined function provided by the software, a new numerical simulation methodology on viscoelastic fluid flows has been established. In order to benchmark this methodology, numerical simulations under different viscoelastic fluid solution concentrations (with solvent viscosity ratio varied from 0.2 to 0.9, extensibility parameters (100≤L2≤500, Reynolds numbers (0.1 ≤ Re ≤ 100, and Weissenberg numbers (0 ≤ Wi ≤ 20 are conducted on unsteady laminar flows through a symmetric planar sudden expansion with expansion ratio of 1: 3 for viscoelastic fluid flows. The constitutive model used to describe the viscoelastic effect of viscoelastic fluid flow is FENE-P (finitely extensive nonlinear elastic-Peterlin model. The numerical simulation results show that the influences of elasticity, inertia, and concentration on the flow bifurcation characteristics are more significant than those of extensibility. The present simulation results including the critical Reynolds number for which the flow becomes asymmetric, vortex size, bifurcation diagram, velocity distribution, streamline, and pressure loss show good agreements with some published results. That means the newly established method based on FLUENT software platform for simulating peculiar flow behaviors of viscoelastic fluid is credible and suitable for the study of viscoelastic fluid flows.

  11. Validation of the 2014 European Society of Cardiology guidelines risk prediction model for the primary prevention of sudden cardiac death in hypertrophic cardiomyopathy.

    Science.gov (United States)

    Vriesendorp, Pieter A; Schinkel, Arend F L; Liebregts, Max; Theuns, Dominic A M J; van Cleemput, Johan; Ten Cate, Folkert J; Willems, Rik; Michels, Michelle

    2015-08-01

    The recently released 2014 European Society of Cardiology guidelines of hypertrophic cardiomyopathy (HCM) use a new clinical risk prediction model for sudden cardiac death (SCD), based on the HCM Risk-SCD study. Our study is the first external and independent validation of this new risk prediction model. The study population consisted of a consecutive cohort of 706 patients with HCM without prior SCD event, from 2 tertiary referral centers. The primary end point was a composite of SCD and appropriate implantable cardioverter-defibrillator therapy, identical to the HCM Risk-SCD end point. The 5-year SCD risk was calculated using the HCM Risk-SCD formula. Receiver operating characteristic curves and C-statistics were calculated for the 2014 European Society of Cardiology guidelines, and risk stratification methods of the 2003 American College of Cardiology/European Society of Cardiology guidelines and 2011 American College of Cardiology Foundation/American Heart Association guidelines. During follow-up of 7.7±5.3 years, SCD occurred in 42 (5.9%) of 706 patients (ages 49±16 years; 34% women). The C-statistic of the new model was 0.69 (95% CI, 0.57-0.82; P=0.008), which performed significantly better than the conventional risk factor models based on the 2003 guidelines (C-statistic of 0.55: 95% CI, 0.47-0.63; P=0.3), and 2011 guidelines (C-statistic of 0.60: 95% CI, 0.50-0.70; P=0.07). The HCM Risk-SCD model improves the risk stratification of patients with HCM for primary prevention of SCD, and calculating an individual risk estimate contributes to the clinical decision-making process. Improved risk stratification is important for the decision making before implantable cardioverter-defibrillator implantation for the primary prevention of SCD. © 2015 American Heart Association, Inc.

  12. Monitoring system of depressurization valves of migrated gas in annular space of flexible risers

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Luiz A.; Santos, Joilson M.; Carvalho, Antonio L.; Loureiro, Patricia [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2005-07-01

    PETROBRAS Research and Development Center - CENPES developed an automatic system for monitoring pressure of annular space due to permeation of gas in flexible risers to inspect continuously integrity of such lines. To help maintaining physical integrity of flexible risers, two PSV's are installed to end fittings on top of riser, so that operation of any valve grants the maximum admissible gas pressure within the riser annular space, as overpressure might cause damages to external polymeric layer of flexible riser. Due to the fact that there is no mechanism allowing operation to verify correct PSV performance and frequency of valve's closings and openings, we felt to be necessary the development and implement an automatic instrumented system, integrated to platform's automation and control infrastructure. The objective of this instrumentation is to monitor and register pressure of annular space in flexible riser, as well as XV's depressurization frequency. Having such information registered and monitored, can infer some riser structural conditions, anticipating repairs and preventive maintenance. In this paper we present developed system details including instruments required, application, operation of associated screens that are used in the ECOS, with events, alarms and industrial automation services required (Application development and system integration). (author)

  13. Sensitivity Analyses in Small Break LOCA with HPI-Failure: Effect of Break-Size in Secondary-Side Depressurization

    Science.gov (United States)

    Kinoshita, Ikuo; Torige, Toshihide; Yamada, Minoru

    2014-06-01

    In the case of total failure of the high pressure injection (HPI) system following small break loss of coolant accident (SBLOCA) in pressurized water reactor (PWR), the break size is so small that the primary system does not depressurize to the accumulator (ACC) injection pressure before the core is uncovered extensively. Therefore, steam generator (SG) secondary-side depressurization is necessary as an accident management in order to grant accumulator system actuation and core reflood. A thermal-hydraulic analysis using RELAP5/MOD3 was made on SBLOCA with HPI-failure for Oi Units 3/4 operated by Kansai Electoric Power Co., which are conventional 4 loop PWR plants. The effectiveness of SG secondary-side depressurization procedure was investigated for the real plant design and operational characteristics. The sensitivity analyses using RELAP5/MOD3.2 showed that the accident management was effective for a wide range of break sizes, various orientations and positions. The critical break can be 3 inch cold-leg bottom break.

  14. Sudden Sensorineural Hearing Loss

    Science.gov (United States)

    Kuhn, Maggie; Heman-Ackah, Selena E.; Shaikh, Jamil A.

    2011-01-01

    Sudden sensorineural hearing loss (SSNHL) is commonly encountered in audiologic and otolaryngologic practice. SSNHL is most commonly defined as sensorineural hearing loss of 30dB or greater over at least three contiguous audiometric frequencies occurring within a 72-hr period. Although the differential for SSNHL is vast, for the majority of patients an etiologic factor is not identified. Treatment for SSNHL of known etiology is directed toward that agent, with poor hearing outcomes characteristic for discoverable etiologies that cause inner ear hair cell loss. Steroid therapy is the current mainstay of treatment of idiopathic SSNHL in the United States. The prognosis for hearing recovery for idiopathic SSNHL is dependent on a number of factors including the severity of hearing loss, age, presence of vertigo, and shape of the audiogram. PMID:21606048

  15. Sudden flaccid paralysis.

    Science.gov (United States)

    Tariq, Mohammad; Peshin, Rohit; Ellis, Oliver; Grover, Karan

    2015-01-07

    Periodic thyrotoxic paralysis is a genetic condition, rare in the West and in Caucasians. Thyrotoxicosis, especially in western hospitals, is an easily overlooked cause of sudden-onset paralysis. We present a case of a 40-year-old man who awoke one morning unable to stand. He had bilateral lower limb flaccid weakness of 0/5 with reduced reflexes and equivocal plantars; upper limbs were 3/5 with reduced tone and reflexes. ECG sinus rhythm was at a rate of 88/min. PR interval was decreased and QT interval increased. Bloods showed potassium of 1.8 mEq/L (normal range 3.5-5), free T4 of 29.2 pmol/L (normal range 6.5-17) and thyroid-stimulating hormone (TSH) of paralysis. He was discharged on carbimazole and propanolol, and follow-up was arranged in the endocrinology clinic.

  16. Sudden Event Recognition: A Survey

    Science.gov (United States)

    Suriani, Nor Surayahani; Hussain, Aini; Zulkifley, Mohd Asyraf

    2013-01-01

    Event recognition is one of the most active research areas in video surveillance fields. Advancement in event recognition systems mainly aims to provide convenience, safety and an efficient lifestyle for humanity. A precise, accurate and robust approach is necessary to enable event recognition systems to respond to sudden changes in various uncontrolled environments, such as the case of an emergency, physical threat and a fire or bomb alert. The performance of sudden event recognition systems depends heavily on the accuracy of low level processing, like detection, recognition, tracking and machine learning algorithms. This survey aims to detect and characterize a sudden event, which is a subset of an abnormal event in several video surveillance applications. This paper discusses the following in detail: (1) the importance of a sudden event over a general anomalous event; (2) frameworks used in sudden event recognition; (3) the requirements and comparative studies of a sudden event recognition system and (4) various decision-making approaches for sudden event recognition. The advantages and drawbacks of using 3D images from multiple cameras for real-time application are also discussed. The paper concludes with suggestions for future research directions in sudden event recognition. PMID:23921828

  17. Micro-seismic Signals Recorded During Fast Depressurization of Natural Volcanic Samples in a Shock Tube Apparatus

    Science.gov (United States)

    Arciniega-Ceballos, A.; Alatorre-Ibargüengoitia, M.; Dingwell, D. B.; Scheu, B.; Delgado Granados, H.; Navarrete Montesinos, M.; Richard, D.; Kueppers, U.; Lavallée, Y.

    2009-12-01

    Volcanic eruptions generate different types of seismic signals in a wide frequency bandwidth. Volcano seismology studies have dealt with analyzing seismic signals characteristics and waveform patterns in order to discriminate between source, path and site effects and reconstruct the volcanic source dynamics. The source may involve brittle failure, magma transport, magma fragmentation, bubble collapse, fluid depressurization, fluid instabilities, degassing or a combination of these processes. Given the complexity of the volcanic source dynamics and the impossibility to undertake direct observations of the source, laboratory experiments provide a promising approach to investigate the source process. In this study we present preliminary results of an experimental approach in a shock tube apparatus. The apparatus consists of two serial steel pipes separated by a diaphragm: the autoclave which represents the "source mechanism", where the samples are pressurized and fragmented, and a tank which represents a conduit. The physical mechanism consists of the slow pressurization (using Argon gas) followed by rapid depressurization of natural samples of ash (> 0.5 mm), pumice (with average porosity of 63%,) and fragmented particles of pumice. Several experiments were designed under controlled pressure conditions (ranging from 4 to 20 MPa), at room temperature. Micro-seismic signals were detected during the depressurization process using high dynamic piezo film sensors (PDF, 0.001 - 10 G Hz analog bandwidth, low impedance), fixed and distributed along the tube system. In addition, two laser beams (wavelength 532 nm) measure the speed of the ejected materials; all sensors were correlated and synchronized with two dynamic pressure sensors located at the autoclave. The resonance of the empty tube apparatus was characterized in order to distinguish between natural resonance of the tank due to the pressure shock wave and the signals generated by depressurization of the system and

  18. Satellite observations and modeling of transport in the upper troposphere through the lower mesosphere during the 2006 major stratospheric sudden warming

    Directory of Open Access Journals (Sweden)

    W. H. Daffer

    2009-07-01

    Full Text Available An unusually strong and prolonged stratospheric sudden warming (SSW in January 2006 was the first major SSW for which globally distributed long-lived trace gas data are available covering the upper troposphere through the lower mesosphere. We use Aura Microwave Limb Sounder (MLS, Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS data, the SLIMCAT Chemistry Transport Model (CTM, and assimilated meteorological analyses to provide a comprehensive picture of transport during this event. The upper tropospheric ridge that triggered the SSW was associated with an elevated tropopause and layering in trace gas profiles in conjunction with stratospheric and tropospheric intrusions. Anomalous poleward transport (with corresponding quasi-isentropic troposphere-to-stratosphere exchange at the lowest levels studied in the region over the ridge extended well into the lower stratosphere. In the middle and upper stratosphere, the breakdown of the polar vortex transport barrier was seen in a signature of rapid, widespread mixing in trace gases, including CO, H2O, CH4 and N2O. The vortex broke down slightly later and more slowly in the lower than in the middle stratosphere. In the middle and lower stratosphere, small remnants with trace gas values characteristic of the pre-SSW vortex lingered through the weak and slow recovery of the vortex. The upper stratospheric vortex quickly reformed, and, as enhanced diabatic descent set in, CO descended into this strong vortex, echoing the fall vortex development. Trace gas evolution in the SLIMCAT CTM agrees well with that in the satellite trace gas data from the upper troposphere through the middle stratosphere. In the upper stratosphere and lower mesosphere, the SLIMCAT simulation does not capture the strong descent of mesospheric CO and H2O values into the reformed vortex; this poor CTM performance in the upper stratosphere and lower mesosphere results

  19. Simulation of the automatic depressurization system (Ads) for a boiling water reactor (BWR) based on RELAP; Simulacion del sistema de despresurizacion automatica (ADS) para un reactor de agua en ebullicion (BWR) basado en RELAP

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez G, C.; Chavez M, C., E-mail: ces.raga@gmail.com [UNAM, Facultad de Ingenieria, Circuito Interior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2012-10-15

    The automatic depressurization system (Ads) of the boiling water reactor (BWR) like part of the emergency cooling systems is designed to liberate the vapor pressure of the reactor vessel, as well as the main vapor lines. At the present time in the Engineering Faculty, UNAM personnel works in the simulation of the Laguna Verde reactor based on the nuclear code RELAP/SCADAP and in the incorporation to the same of the emergency cooling systems. The simulation of the emergency cooling systems began with the inclusion of two hydrodynamic volumes, one source and another drain, and the incorporation of the initiation logic for each emergency system. In this work is defined and designed a simplified model of Ads of the reactor, considering a detail level based on the main elements that compose it. As tool to implement the proposed model, the RELAP code was used. The simulated main functions of Ads are centered in the quick depressurization of the reactor by means of the vapor discharge through the relief/safety valves to the suppression pool, and, in the event of break of the main vapor line, the reduction of the vessel pressure operates for that the cooling systems of the core to low pressure (Lpcs and Lpci) they can begin their operation. (Author)

  20. [Genetics of sudden unexplained death].

    Science.gov (United States)

    Campuzano, Oscar; Allegue, Catarina; Brugada, Ramon

    2014-03-20

    Sudden unexplained death is defined by death without a conclusive diagnosis after autopsy and it is responsible for a large percentage of sudden deaths. The progressive interaction between genetics and forensics in post-mortem studies has identified inheritable alterations responsible for pathologies associated with arrhythmic sudden death. The genetic diagnosis of the deceased enables the undertaking of preventive measures in family members, many of them asymptomatic but at risk. The implications of this multidisciplinary translational medical approach are complex, requiring the dedication of a specialized team. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  1. Effects of Fluid Saturation on Gas Recovery from Class-3 Hydrate Accumulations Using Depressurization: Case Study of Yuan-An Ridge Site in Southwestern Offshore Taiwan

    Science.gov (United States)

    Huang, Yi-Jyun; Wu, Cheng-Yueh; Hsieh, Bieng-Zih

    2016-04-01

    Gas hydrates are crystalline compounds in which guest gas molecules are trapped in host lattices of ice crystals. In Taiwan, the significant efforts have recently begun to evaluate the reserves of hydrate because the vast accumulations of gas hydrates had been recognized in southwestern offshore Taiwan. Class-3 type hydrate accumulations are referred to an isolated hydrate layer without an underlying zone of mobile fluids, and the entire hydrate layer may be well within the hydrate stability zone. The depressurization method is a useful dissociation method for gas production from Class-3 hydrate accumulations. The dissociation efficiency is controlled by the responses of hydrate to the propagating pressure disturbance, and the pressure propagation is relating to the amount (or saturation) of the mobile fluid in pore space of the hydrate layer. The purpose of this study is to study the effects of fluid saturation on the gas recovery from a class-3 hydrate accumulation using depressurization method. The case of a class-3 hydrate deposit of Yuan-An Ridge in southwestern offshore Taiwan is studied. The numerical method was used in this study. The reservoir simulator we used to study the dissociation of hydrate and the production of gas was the STARS simulator developed by CMG, which coupled heat transfer, geo-chemical, geo-mechanical, and multiphase fluid flow mechanisms. The study case of Yuan-An Ridge is located in southwestern offshore Taiwan. The hydrate deposit was found by the bottom simulating reflectors (BSRs). The geological structure of the studied hydrate deposit was digitized to build the geological model (grids) of the case. The formation parameters, phase behavior data, rock and fluid properties, and formation's initial conditions were assigned sequentially to grid blocks, and the completion and operation conditions were designed to wellbore blocks to finish the numerical model. The changes of reservoir pressure, temperature, saturation due to the hydrate

  2. Sudden cardiac death in athletes

    Directory of Open Access Journals (Sweden)

    Fábio Camilo Pellegrino dos Santos

    2012-11-01

    Full Text Available ABSTRACT The most accepted definition of sudden cardiac death nowadays is an unexplained death occurred suddenly within one hour of symptom onset. If it was not witnessed, individuals need to had been observed for at least 24 hours before the event and should be discarded the possibility of non cardiac causes of sudden death, pulmonary embolism or extensive malignancy. The term athlete refers to individuals of any age who participate in collective or individual regular physical activity, as well as physical training program for regular competitions. The sudden death of a young athlete, whether amateur or professional, especially during competitions, is always dramatic, with strong negative social impact and in the media. The fact that sports are recommended as a formula for longevity and quality of life makes these events a cause for concern in sports and society in general.

  3. Sudden death in eating disorders.

    Science.gov (United States)

    Jáuregui-Garrido, Beatriz; Jáuregui-Lobera, Ignacio

    2012-01-01

    Eating disorders are usually associated with an increased risk of premature death with a wide range of rates and causes of mortality. "Sudden death" has been defined as the abrupt and unexpected occurrence of fatality for which no satisfactory explanation of the cause can be ascertained. In many cases of sudden death, autopsies do not clarify the main cause. Cardiovascular complications are usually involved in these deaths. The purpose of this review was to report an update of the existing literature data on the main findings with respect to sudden death in eating disorders by means of a search conducted in PubMed. The most relevant conclusion of this review seems to be that the main causes of sudden death in eating disorders are those related to cardiovascular complications. The predictive value of the increased QT interval dispersion as a marker of sudden acute ventricular arrhythmia and death has been demonstrated. Eating disorder patients with severe cardiovascular symptoms should be hospitalized. In general, with respect to sudden death in eating disorders, some findings (eg, long-term eating disorders, chronic hypokalemia, chronically low plasma albumin, and QT intervals >600 milliseconds) must be taken into account, and it must be highlighted that during refeeding, the adverse effects of hypophosphatemia include cardiac failure. Monitoring vital signs and performing electrocardiograms and serial measurements of plasma potassium are relevant during the treatment of eating disorder patients.

  4. Sudden death in eating disorders

    Directory of Open Access Journals (Sweden)

    Jáuregui-Garrido B

    2012-02-01

    Full Text Available Beatriz Jáuregui-Garrido1, Ignacio Jáuregui-Lobera2,31Department of Cardiology, University Hospital Virgen del Rocío, 2Behavioral Sciences Institute, 3Pablo de Olavide University, Seville, SpainAbstract: Eating disorders are usually associated with an increased risk of premature death with a wide range of rates and causes of mortality. “Sudden death” has been defined as the abrupt and unexpected occurrence of fatality for which no satisfactory explanation of the cause can be ascertained. In many cases of sudden death, autopsies do not clarify the main cause. Cardiovascular complications are usually involved in these deaths. The purpose of this review was to report an update of the existing literature data on the main findings with respect to sudden death in eating disorders by means of a search conducted in PubMed. The most relevant conclusion of this review seems to be that the main causes of sudden death in eating disorders are those related to cardiovascular complications. The predictive value of the increased QT interval dispersion as a marker of sudden acute ventricular arrhythmia and death has been demonstrated. Eating disorder patients with severe cardiovascular symptoms should be hospitalized. In general, with respect to sudden death in eating disorders, some findings (eg, long-term eating disorders, chronic hypokalemia, chronically low plasma albumin, and QT intervals >600 milliseconds must be taken into account, and it must be highlighted that during refeeding, the adverse effects of hypophosphatemia include cardiac failure. Monitoring vital signs and performing electrocardiograms and serial measurements of plasma potassium are relevant during the treatment of eating disorder patients.Keywords: sudden death, cardiovascular complications, refeeding syndrome, QT interval, hypokalemia

  5. Communication: Ro-vibrational control of chemical reactivity in H+CH{sub 4}→ H{sub 2}+CH{sub 3} : Full-dimensional quantum dynamics calculations and a sudden model

    Energy Technology Data Exchange (ETDEWEB)

    Welsch, Ralph, E-mail: rwelsch@uni-bielefeld.de; Manthe, Uwe, E-mail: uwe.manthe@uni-bielefeld.de [Theoretische Chemie, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld (Germany)

    2014-08-07

    The mode-selective chemistry of the title reaction is studied by full-dimensional quantum dynamics simulation on an accurate ab initio potential energy surface for vanishing total angular momentum. Using a rigorous transition state based approach and multi-configurational time-dependent Hartree wave packet propagation, initial state-selected reaction probabilities for many ro-vibrational states of methane are calculated. The theoretical results are compared with experimental trends seen in reactions of methane. An intuitive interpretation of the ro-vibrational control of the chemical reactivity provided by a sudden model based on the quantum transition state concept is discussed.

  6. Investigating Insight as Sudden Learning

    Science.gov (United States)

    Ash, Ivan K.; Jee, Benjamin D.; Wiley, Jennifer

    2012-01-01

    Gestalt psychologists proposed two distinct learning mechanisms. Associative learning occurs gradually through the repeated co-occurrence of external stimuli or memories. Insight learning occurs suddenly when people discover new relationships within their prior knowledge as a result of reasoning or problem solving processes that re-organize or…

  7. [The Sudden Infant Death Syndrome.

    Science.gov (United States)

    Florida's Health, 1976

    1976-01-01

    This collection of articles on the Sudden Infant Death Syndrome (SIDS), drawn from a southeastern regional symposium on the subject, summarizes much of what is known about the occurrence of SIDS, including current information about its causes. The background of state action in Florida is reviewed, with emphasis on the need for increased public and…

  8. DESIGN AND TESTING OF SUB-SLAB DEPRESSURIZATION FOR RADON MITIGATION IN NORTH FLORIDA HOUSES - PART I. PERFORMANCE AND DURABILITY - VOLUME 1. TECHNICAL REPORT

    Science.gov (United States)

    The report gives results of a demonstration/research project to evaluate sub-slab depressurization (SSD) techniques for radon mitigation in North Florida where the housing stock is primarily slab-on-grade and the sub-slab medium typically consists of native soil and sand. Objecti...

  9. Sudden Infant Death Syndrome: Facts for Caregivers.

    Science.gov (United States)

    Texas Child Care, 2000

    2000-01-01

    Presents risk factors and prevention measures related to Sudden Infant Death Syndrome. Offers infant sleep recommendations and five discussion questions to test knowledge of Sudden Infant Death Syndrome. (DLH)

  10. Sudden gains in behavioural activation for depression.

    Science.gov (United States)

    Masterson, Ciara; Ekers, David; Gilbody, Simon; Richards, David; Toner-Clewes, Benjamin; McMillan, Dean

    2014-09-01

    Sudden gains have been linked to improved outcomes in cognitive behaviour therapy for depression. The relationship between sudden gains and outcome is less clear in other treatment modalities, including interpersonal psychotherapy and supportive expressive therapy, which may indicate different mechanisms of change between treatment modalities. The current study examined sudden gains in adults meeting diagnostic criteria for depression (N = 40) offered up to 12 sessions of behavioural activation treatment. Sudden gains were found in 42.5% of the sample. Sudden gains occurred early (median pre-gain session 2) and were related to outcome: those who experienced a sudden gain had significantly lower post-treatment scores on the PHQ-9. Furthermore, the proportion meeting the reliable and clinically significant change criteria at end of treatment was higher in the sudden gain group. These findings highlight the importance of understanding the mechanisms by which sudden gains relate to therapy outcome in behavioural activation.

  11. Sudden Hadronization in Relativistic Nuclear Collisions

    CERN Document Server

    Rafelski, Johann; Rafelski, Johann; Letessier, Jean

    2000-01-01

    We formulate and study the mechanical instability criterion of dense matter fireballs without considering a specific equation of state (EoS). We demonstrate the consistency with the chemical freeze-out of a fireball of matter formed in 158AGeV Pb-Pb collisions. Assuming EoS appropriate for quark-gluon matter, we demonstrate the required deep QGP supercooling prior to sudden hadronization. In a model independent approach, but using results of hadron abundance analysis and lattice QCD, we show that the latent heat of the deconfined phase is bounded from below 0.14GeV/fm^3\\le B.

  12. Episodes of repeated sudden deafness following pregnancies.

    Science.gov (United States)

    Pawlak-Osinska, Katarzyna; Burduk, Pawel K; Kopczynski, Andrzej

    2009-04-01

    Sex hormones influence and provoke changes in hearing levels. Sudden deafness is rarely observed in pregnant women. The effective treatment of sudden deafness in pregnant women is a challenging problem. We present a case of repeatable, completely regressed sudden deafness in a woman during her first and second pregnancies.

  13. Coupled catastrophes: sudden shifts cascade and hop among interdependent systems

    CERN Document Server

    Brummitt, Charles D; D'Souza, Raissa M

    2014-01-01

    A profoundly important challenge in several disciplines today is to understand how sudden changes can propagate among coupled systems. Examples include the synchronization of business cycles, population collapse in patchy ecosystems, markets shifting to a new technology platform, collapses in prices and in confidence in financial markets, and protests erupting in multiple countries. We characterize these phenomena using a simple model grounded in the theory of fast--slow ordinary differential equations and in catastrophe theory. In the model, a system consists of multiple subsystems (e.g., countries in the global economy or patches of an ecosystem), each described by a scalar quantity (such as economic output or population) that undergoes sudden changes via saddle-node bifurcations. The subsystems are coupled via their scalar quantities (e.g., trade couples economic output, diffusion couples populations); that coupling moves their bifurcations. The model elucidates two ways in which sudden changes can propaga...

  14. Sudden death in eating disorders

    OpenAIRE

    Jáuregui-Garrido B; Jáuregui-Lobera I

    2012-01-01

    Beatriz Jáuregui-Garrido1, Ignacio Jáuregui-Lobera2,31Department of Cardiology, University Hospital Virgen del Rocío, 2Behavioral Sciences Institute, 3Pablo de Olavide University, Seville, SpainAbstract: Eating disorders are usually associated with an increased risk of premature death with a wide range of rates and causes of mortality. “Sudden death” has been defined as the abrupt and unexpected occurrence of fatality for which no satisfact...

  15. Emergency control system based on the analytical hierarchy process and coordinated development degree model for sudden water pollution accidents in the Middle Route of the South-to-North Water Transfer Project in China.

    Science.gov (United States)

    Long, Yan; Xu, Guobin; Ma, Chao; Chen, Liang

    2016-06-01

    Water transfer projects are important for realizing reasonable allocation of water resources, but once a water pollution accident occurs during such a project, the water environment is exposed to enormous risks. Therefore, it is critical to determine an appropriate emergency control system (ECS) for sudden water pollution accidents that occur in water transfer projects. In this study, the analytical hierarchy process (AHP) integrated with the coordinated development degree model (CDDM) was used to develop the ECS. This ECS was developed into two parts, including the emergency risk assessment and the emergency control. Feasible emergency control targets and control technology were also proposed for different sudden water pollution accidents. A demonstrative project was conducted in the Fangshui to Puyang channel, which is part of the Beijing-Shijiazhuang Emergency Water Supply Project (BSP) in the Middle Route of the South-to-North Water Transfer Project (MR-SNWTP) in China. However, we could not use an actual toxic soluble pollutant to validate our ECS, so we performed the experiment with sucrose to test the ECS based on its concentration variation. The relative error of peak sucrose concentration was less than 20 %.

  16. Pediatric Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Kizilay, Ahmet; Koca, Çiğdem Firat

    2016-06-01

    Sudden sensorineural hearing loss is defined as sudden unilateral or bilateral sensorineural hearing loss with at least 30 dB decrease in threshold in 3 contiguous test frequencies occurring over 72 hours or less. It is rare among children. The mechanism of the process and prognosis of the disorder remains unclear. The current incidence of sudden sensorineural hearing loss among pediatric population is unknown. The authors carried out a retrospective chart analysis of patients under 15 years of age from 2004 to 2015, who consulted to the Otolaryngology Head and Neck Surgery Department of Inonu University Medical Faculty. Age, sex, number of affected ear and side, audiometric evaluations, medical follow-up, treatment method, duration of treatment recovery, associated complaints; tinnitus and/or vertigo, presence of mumps disease were recorded for each patient. A 4-frequency pure-tone average (500, 1000, 2000, and 4000 Hz) was calculated for each ear. Complete recovery, defined as some hearing level compared with the nonaffected ear, was observed in 3 patients (21.4 %) and there was no partial hearing recovery. The hearing loss of 11 patient remained unchanged after prednisolone treatment. Two of the 11 patients had bilaterally total sensorineural hearing loss and evaluated as appropriate for cochlear implantation. Sex of patient and laterality of hearing loss were not correlated with hearing recovery. Sensorineural hearing loss among pediatrics has been the issue of otolaryngologists. The incidence, etiology, and treatment methods should be more studied.

  17. [Sound therapy in sudden deafness].

    Science.gov (United States)

    López-González, Miguel A; Cambil, Esther; Abrante, Antonio; López-Fernández, Rocío; Esteban, Francisco

    2012-01-01

    Idiopathic sudden sensorineural hearing loss is a hearing disorder of unknown cause. The spontaneous recovery rate ranges from 50 to 75% of the patients. Scientific experiments on animals support the present study in patients with sudden deafness treated with sounds. During the period 2003-2009, patients with idiopathic sudden sensorineural hearing loss were administered steroids, piracetam and antioxidants, together with the addition of sounds by means of music and words. Comparing the results of patients treated with medication (n=65) and those treated with medication and sounds (n=67), it was observed that patients treated with medication and sounds had higher recovery. Within the group of patients treated with medication and sounds, 25 (37%) experienced complete recovery, 28 (42%) good recovery, 11 (16%) slight recovery and 3 (5%) poor or no recovery. The patients who recovered more than half of their audition accounted for 54% in the group treated with medication and for 79% in the group of patients receiving medication and sounds. Auditory recuperation showed no alterations, at least up to 12 months after therapy. Copyright © 2011 Elsevier España, S.L. All rights reserved.

  18. Stratospheric sudden warming and lunar tide

    Science.gov (United States)

    Yamazaki, Yosuke; Kosch, Michael

    2016-07-01

    A stratospheric sudden warming is a large-scale disturbance in the middle atmosphere. Recent studies have shown that the effect of stratospheric sudden warnings extends well into the upper atmosphere. A stratospheric sudden warming is often accompanied by an amplification of lunar tides in the ionosphere/theremosphere. However, there are occasionally winters when a stratospheric sudden warming occurs without an enhancement of the lunar tide in the upper atmosphere, and other winters when large lunar tides are observed without a strong stratospheric sudden warming. We examine the winters when the correlation breaks down and discuss possible causes.

  19. Sudden Trust Collapse in Networked Societies

    CERN Document Server

    Batista, João da Gama; Challet, Damien

    2014-01-01

    Trust is a collective, self-fulfilling phenomenon that suggests analogies with phase transitions. We introduce a stylized model for the build-up and collapse of trust in networks, which generically displays a first order transition. The basic assumption of our model is that whereas trust begets trust, panic also begets panic, in the sense that a small decrease in trust may be amplified and ultimately lead to a sudden and catastrophic drop of trust. We show, using both numerical simulations and mean-field analytic arguments, that there are extended regions of the parameter space where two equilibrium states coexist: a well-connected network where confidence is high, and a poorly connected network where confidence is low. In these coexistence regions, spontaneous jumps from the well-connected state to the poorly connected state can occur, corresponding to a sudden collapse of trust that is not caused by any major external catastrophe. In large systems, spontaneous crises are replaced by history dependence: whet...

  20. Numerical simulations of depressurization-induced gas production from gas hydrate reservoirs at the Walker Ridge 312 site, northern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Myshakin, Evgeniy M.; Gaddipati, Manohar; Rose, Kelly; Anderson, Brian J.

    2012-06-01

    In 2009, the Gulf of Mexico (GOM) Gas Hydrates Joint-Industry-Project (JIP) Leg II drilling program confirmed that gas hydrate occurs at high saturations within reservoir-quality sands in the GOM. A comprehensive logging-while-drilling dataset was collected from seven wells at three sites, including two wells at the Walker Ridge 313 site. By constraining the saturations and thicknesses of hydrate-bearing sands using logging-while-drilling data, two-dimensional (2D), cylindrical, r-z and three-dimensional (3D) reservoir models were simulated. The gas hydrate occurrences inferred from seismic analysis are used to delineate the areal extent of the 3D reservoir models. Numerical simulations of gas production from the Walker Ridge reservoirs were conducted using the depressurization method at a constant bottomhole pressure. Results of these simulations indicate that these hydrate deposits are readily produced, owing to high intrinsic reservoir-quality and their proximity to the base of hydrate stability. The elevated in situ reservoir temperatures contribute to high (5–40 MMscf/day) predicted production rates. The production rates obtained from the 2D and 3D models are in close agreement. To evaluate the effect of spatial dimensions, the 2D reservoir domains were simulated at two outer radii. The results showed increased potential for formation of secondary hydrate and appearance of lag time for production rates as reservoir size increases. Similar phenomena were observed in the 3D reservoir models. The results also suggest that interbedded gas hydrate accumulations might be preferable targets for gas production in comparison with massive deposits. Hydrate in such accumulations can be readily dissociated due to heat supply from surrounding hydrate-free zones. Special cases were considered to evaluate the effect of overburden and underburden permeability on production. The obtained data show that production can be significantly degraded in comparison with a case using

  1. Sudden unexpected death caused by stroke

    DEFF Research Database (Denmark)

    Ågesen, Frederik Nybye; Risgaard, Bjarke; Zachariasardóttir, Sára

    2017-01-01

    Background Stroke is the fifth leading cause of death in young individuals globally. Data on the burden of sudden death by stroke are sparse in the young. Aims The aim of this study was to report mortality rates, cause of death, stroke subtype, and symptoms in children and young adults who suffered...... sudden death by stroke. Methods We conducted a retrospective, nationwide study including all deaths within Danish borders between 2000-2009 and 2007-2009 in persons aged 1-35 years and 36-49 years, respectively. Two physicians identified all sudden death cases through review of all death certificates....... All available autopsy reports and records from hospitals and general practitioners were retrieved and a neurologist identified all sudden death by stroke cases. Results Of the 14,567 deaths in the 10-year period, there were 1,698 sudden death cases, of which 52 (3%) were sudden death by stroke...

  2. Containment Depressurization Capabilities of Filtered Venting System in 1000 MWe PWR with Large Dry Containment

    Directory of Open Access Journals (Sweden)

    Sang-Won Lee

    2014-01-01

    Full Text Available After the Fukushima Daiichi nuclear power plant accident, the Korean government and nuclear industries performed comprehensive safety inspections on all domestic nuclear power plants against beyond design bases events. As a result, a total of 50 recommendations were defined as safety improvement action items. One of them is installation of a containment filtered venting system (CFVS or portable backup containment spray system. In this paper, the applicability of CFVS is examined for OPR1000, a 1000 MWe PWR with large dry containment in Korea. Thermohydraulic analysis results show that a filtered discharge flow rate of 15 [kg/s] at 0.9 [MPa] is sufficient to depressurize the containment against representative containment overpressurization scenarios. Radiological release to the environment is reduced to 10-3 considering the decontamination factor. Also, this cyclic venting strategy reduces noble gas release by 50% for 7 days. The probability of maintaining the containment integrity in level 2 probabilistic safety assessment (PSA initiating events is improved twofold, from 43% to 87%. So, the CFVS can further improve the containment integrity in severe accident conditions.

  3. Book Review: "Sudden Wealth...It Happens."

    Directory of Open Access Journals (Sweden)

    Erika Rasure

    2013-08-01

    Full Text Available “Sudden Wealth…It Happens” is an exploration of circumstances that can drastically change one’s financial future. A collection of cautionary, yet inspiring tales, sets the tone for emphasizing the importance of sudden wealth financial management. What follows is a sudden wealth management toolkit intended to guide the recipient of a windfall down the path of financial success, and away from the path of financial ruin.

  4. Medulloblastoma Manifesting as Sudden Sensorineural Hearing Loss

    OpenAIRE

    Terakawa, Yuzo; Tsuyuguchi, Naohiro; Takami, Toshihiro; Ohata, Kenji

    2011-01-01

    We present a rare case of medulloblastoma which presented with unilateral sudden sensorineural hearing loss as an initial symptom. A 19-year-old man was admitted to our hospital with a chief complaint of dizziness and facial numbness on the right side. His illness had begun two years previously with sudden hearing loss on the right side, for which he had been treated as an idiopathic sudden hearing loss. Magnetic resonance imaging demonstrated abnormal signals located mainly in the right midd...

  5. Controllable entanglement sudden birth of Heisenberg spins

    Institute of Scientific and Technical Information of China (English)

    ZHENG Qiang; ZHI Qi-Jun; ZHANG Xiao-ping; REN Zhong-Zhou

    2011-01-01

    We investigate the Entanglement Sudden Birth (ESB) of two Heisenberg spins A and B. The third controller, qutrit C is introduced, which only has the Dzyaloshinskii-Moriya (DM) spin-orbit interaction with qubit B. We find that the DM interaction is necessary to induce the Entanglement Sudden Birth of the system qubits A and B, and the initial states of the system qubits and the qurit C are also important to control its Entanglement Sudden Birth.

  6. New Isotropic and Anisotropic Sudden Singularities

    CERN Document Server

    Barrow, J D; Barrow, John D.; Tsagas, Christos G.

    2004-01-01

    We show the existence of an infinite family of finite-time singularities in isotropically expanding universes which obey the weak, strong, and dominant energy conditions. We show what new type of energy condition is needed to exclude them ab initio. We also determine the conditions under which finite-time future singularities can arise in a wide class of anisotropic cosmological models. New types of finite-time singularity are possible which are characterised by divergences in the time-rate of change of the anisotropic-pressure tensor. We investigate the conditions for the formation of finite-time singularities in a Bianchi type $VII_{0}$ universe with anisotropic pressures and construct specific examples of anisotropic sudden singularities in these universes.

  7. Experimental investigation of iodine removal and containment depressurization in containment spray system test facility of 700 MWe Indian pressurized heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Manish [Department of Mechanical Engineering, I.I.T., Bombay, Powai, Mumbai (India); Kandar, T.K.; Vhora, S.F.; Mohan, Nalini [Directorate of Technology Development, Nuclear Power Corporation of India Limited, Mumbai (India); Iyer, K.N. [Department of Mechanical Engineering, I.I.T., Bombay, Powai, Mumbai (India); Prabhu, S.V., E-mail: svprabhu@iitb.ac.in [Department of Mechanical Engineering, I.I.T., Bombay, Powai, Mumbai (India)

    2017-05-15

    Highlights: • Depressurization rate in a scaled down vessel filled with air and steam is studied. • Iodine removal rate in a scaled down vessel filled with steam/air is investigated. • Effect of SMD and vessel pressure on depressurization rate is studied. • Depressurization rate decreases with the increase in the droplet size (590 μm – 1 mm) • Decrease in pressure and iodine concentration with time follow exponential trend. - Abstract: As an additional safety measure in the new 700 MWe Indian pressurized heavy water reactors, the first of a kind system called containment Spray System is introduced. The system is designed to cater/mitigate the conditions after design basis accidents i.e., loss of coolant accident and main steam line break. As a contribution to the safety analysis of condition following loss-of-coolant accidents, experiments are carried out to establish the performance of the system. The loss of coolant is simulated by injecting saturated steam and iodine vapors into the containment vessel in which air is enclosed at atmospheric and room temperature, and then the steam-air mixture is cooled by sprays of water. The effect of water spray on the containment vessel pressure and the iodine scrubbing in a scaled down facility is investigated for the containment spray system of Indian pressurized heavy water reactors. The experiments are carried out in the scaled down vessel of the diameter of 2.0 m and height of 3.5 m respectively. Experiments are conducted with water at room temperature as the spray medium. Two different initial vessel pressure i.e. 0.7 bar and 1.0 bar are chosen for the studies as they are nearing the loss of coolant accident & main steam line break pressures in Indian pressurized heavy water reactors. These pressures are chosen based on the containment resultant pressures after a design basis accident. The transient temperature and pressure distribution of the steam in the vessel are measured during the depressurization

  8. Drugs, QTc prolongation and sudden cardiac death

    NARCIS (Netherlands)

    S.M.J.M. Straus (Sabine)

    2005-01-01

    textabstract__Abstract__ The term sudden cardiac death pertains to an unexpected death from cardiac causes within a short time period and has been described throughout history. The ancient Egyptians inscribed on the tomb of a nobleman some 4500 years ago that he had died suddenly and without appare

  9. Athletes at Risk for Sudden Cardiac Death

    Science.gov (United States)

    Subasic, Kim

    2010-01-01

    High school athletes represent the largest group of individuals affected by sudden cardiac death, with an estimated incidence of once or twice per week. Structural cardiovascular abnormalities are the most frequent cause of sudden cardiac death. Athletes participating in basketball, football, track, soccer, baseball, and swimming were found to…

  10. Sudden sensorineural hearing loss after heroin injection.

    Science.gov (United States)

    Schrock, Andreas; Jakob, Mark; Wirz, Stefan; Bootz, Friedrich

    2008-05-01

    Sudden sensorineural hearing loss is a symptom of cochlear injury. Potential aetiologies are vascular diseases, viral infections, allergic reactions, autoimmune disorders, and traumatic rupture of the intralabyrinthe membrane. Unlike in unilateral cases bilateral sensorineural hearing loss is often associated with specific disease entities. We report a case of sudden bilateral deafness after intravenous heroin abuse. The putative pathophysiological mechanisms are discussed.

  11. Drugs, QTc prolongation and sudden cardiac death

    NARCIS (Netherlands)

    S.M.J.M. Straus (Sabine)

    2005-01-01

    textabstract__Abstract__ The term sudden cardiac death pertains to an unexpected death from cardiac causes within a short time period and has been described throughout history. The ancient Egyptians inscribed on the tomb of a nobleman some 4500 years ago that he had died suddenly and without

  12. 多介质模型在海湾突发性有机污染中的应用及案例分析%Application of Multimedia Model for Sudden Organic Pollution in Bays and Case Analysis

    Institute of Scientific and Technical Information of China (English)

    莫俊超; 张海生; 薛斌; 刘小涯; 张海娜

    2011-01-01

    为弥补海洋环境监测能力不足,利用受潮汐动力控制海湾中的多介质模型,预测突发性污染发生后海洋环境中污染物的浓度变化信息,并对突发性污染物的迁移转化进行了计算.模型中使用逸度方法和质量平衡算法,预测非挥发性有机物在水、沉积物和鱼中的浓度.在象山港的应用结果表明,该模型可较快速地给出污染物在不同介质中的浓度变化信息,为环境监测和管理提供帮助.%In order to supply deficiency of marine environment monitoring at sudden pollution accident, multimedia model for bays controlled by tidal dynamics was used to predict pollutant concentration in sea water, and calculate pollutant quantity of transformation and migration. The model by using fugacity and mass balance method estimated the concentration of no-volatile organic compound in phases of water, sediment and fish. Application result in Xiangshan Harbour indicated that model could quickly give information of pollutant concentration changes in different medium, and help environmental monitoring and management.

  13. Sudden Death in Young People--Heart Problems Often Blamed

    Science.gov (United States)

    Sudden death in young people: Heart problems often blamed Sudden death in young people is rare, but those at ... causes and treatments. By Mayo Clinic Staff Sudden death in people younger than 35, often due to ...

  14. Sudden cardiac death risk stratification.

    Science.gov (United States)

    Deyell, Marc W; Krahn, Andrew D; Goldberger, Jeffrey J

    2015-06-01

    Arrhythmic sudden cardiac death (SCD) may be caused by ventricular tachycardia/fibrillation or pulseless electric activity/asystole. Effective risk stratification to identify patients at risk of arrhythmic SCD is essential for targeting our healthcare and research resources to tackle this important public health issue. Although our understanding of SCD because of pulseless electric activity/asystole is growing, the overwhelming majority of research in risk stratification has focused on SCD-ventricular tachycardia/ventricular fibrillation. This review focuses on existing and novel risk stratification tools for SCD-ventricular tachycardia/ventricular fibrillation. For patients with left ventricular dysfunction or myocardial infarction, advances in imaging, measures of cardiac autonomic function, and measures of repolarization have shown considerable promise in refining risk. Yet the majority of SCD-ventricular tachycardia/ventricular fibrillation occurs in patients without known cardiac disease. Biomarkers and novel imaging techniques may provide further risk stratification in the general population beyond traditional risk stratification for coronary artery disease alone. Despite these advances, significant challenges in risk stratification remain that must be overcome before a meaningful impact on SCD can be realized.

  15. Storm sudden commencements and earthquakes

    Science.gov (United States)

    Lavrov, Ivan; Sobisevich, Aleksey; Guglielmi, Anatol

    2015-03-01

    We have investigated statistically the problem of possible impact of the geomagnetic storm sudden com-mencement (SSC) on the global seismic activity. SSC are used as reference points for comparative analysis of seismicity by the method of superposed epoch. We selected 405 earthquakes from 1973 to 2010 with M˜5 magnitudes from a representative part of USGS Catalog. The comparative analysis of seismicity was carried out at the intervals of ˜60 min relative to the reference point. With a high degree of reliability, it was found that before the reference point the number of earthquakes is noticeably greater than after it. In other words, the global seismicity is suppressed by SSC. We refer to some studies in which the chemical, thermal and force mechanisms of the electromagnetic field action on rocks are discussed. We emphasize the incompleteness of the study concerning the correlation between SSC and earthquakes because we still do not succeed in understanding and interpreting the relationship in terms of physics and mathematics. The study need to be continued to solve this problem of interest and importance.

  16. A sudden stratospheric warming compendium

    Science.gov (United States)

    Butler, Amy H.; Sjoberg, Jeremiah P.; Seidel, Dian J.; Rosenlof, Karen H.

    2017-02-01

    Major, sudden midwinter stratospheric warmings (SSWs) are large and rapid temperature increases in the winter polar stratosphere are associated with a complete reversal of the climatological westerly winds (i.e., the polar vortex). These extreme events can have substantial impacts on winter surface climate, including increased frequency of cold air outbreaks over North America and Eurasia and anomalous warming over Greenland and eastern Canada. Here we present a SSW Compendium (SSWC), a new database that documents the evolution of the stratosphere, troposphere, and surface conditions 60 days prior to and after SSWs for the period 1958-2014. The SSWC comprises data from six different reanalysis products: MERRA2 (1980-2014), JRA-55 (1958-2014), ERA-interim (1979-2014), ERA-40 (1958-2002), NOAA20CRv2c (1958-2011), and NCEP-NCAR I (1958-2014). Global gridded daily anomaly fields, full fields, and derived products are provided for each SSW event. The compendium will allow users to examine the structure and evolution of individual SSWs, and the variability among events and among reanalysis products. The SSWC is archived and maintained by NOAA's National Centers for Environmental Information (NCEI, http://dx.doi.org/10.7289/V5NS0RWP" target="_blank">doi:10.7289/V5NS0RWP).

  17. Supravalvular aortic stenosis with sudden cardiac death

    Directory of Open Access Journals (Sweden)

    Pradeep Vaideeswar

    2015-01-01

    Full Text Available Sudden cardiac death (SCD most commonly results from previously undiagnosed congenital, acquired, or hereditary cardiac diseases. Congenital aortic valvular, subvalvular, and supravalvular disease with left ventricular outflow tract obstruction is an important preventable cause of sudden death. This report documents sudden death presumably due to acute myocardial ischemia in a young male with an undiagnosed supravalvular aortic stenosis (SVAS due to a rare association of isolation of coronary sinuses of Valsalva. Congenital supravalvular pulmonary stenosis and mitral valvular dysplasia were also present.

  18. Sudden bilateral hearing loss after organophosphate inhalation

    OpenAIRE

    Dundar, Mehmet Akif; Derin, Serhan; Aricigil, Mitat; Eryilmaz, Mehmet Akif

    2016-01-01

    Sudden bilateral hearing loss are seen rarely and the toxic substance exposure constitutes a small part of etiology. A Fifty-eight-year-old woman admitted to our clinic with sudden bilateral hearing loss shortly after chlorpyrifos-ethyl exposure. Otolaryngologic examination findings were normal. The patient had 40 dB sensorineural hearing loss (SNHL) on the right ear and 48 dB SNHL on the left ear. Additional diagnostic tests were normal. The conventional treatment for sudden hearing loss was...

  19. Unilateral sudden hearing loss due to otosyphilis

    Directory of Open Access Journals (Sweden)

    Maaike J. de Goffau

    2011-12-01

    Full Text Available The differential diagnosis of sudden hearing loss is very extensive. However, in most patients, no underlying pathology will be found and the patient is consequently diagnosed with idiopathic sudden hearing loss. Nevertheless, it is important that one stays alert in everyday routine practice to less common but potentially treatable pathology. We report a case of a 53- year old patient with sudden unilateral hearing loss and tinnitus caused by otosyphilis. Diagnosis, therapy and the incidence of (otosyphilis are discussed. Also, as ENT-surgeons, it is important to realise that syphilis is still with us, and that its prevalence might well increase in the near future.

  20. Sudden bilateral hearing loss after organophosphate inhalation

    OpenAIRE

    Dundar, Mehmet Akif; Derin, Serhan; Aricigil, Mitat; Eryilmaz, Mehmet Akif

    2016-01-01

    Sudden bilateral hearing loss are seen rarely and the toxic substance exposure constitutes a small part of etiology. A Fifty-eight-year-old woman admitted to our clinic with sudden bilateral hearing loss shortly after chlorpyrifos-ethyl exposure. Otolaryngologic examination findings were normal. The patient had 40 dB sensorineural hearing loss (SNHL) on the right ear and 48 dB SNHL on the left ear. Additional diagnostic tests were normal. The conventional treatment for sudden hearing loss was...

  1. Sub-Tg features of glasses formed by cooling glycerol under pressure - Additional incompatibility of vibrational with configurational states in the depressurized, high density glass

    Science.gov (United States)

    Andersson, Ove; Johari, G. P.

    2016-11-01

    The vibrational state of a glass is naturally incompatible with its configurational state, which makes the glass structurally unstable. When a glass is kept at constant temperature, both the vibrational and configurational states of a glass change with time until it becomes metastable (equilibrium) liquid and the two states become compatible. The process, known as structural relaxation, occurs at a progressively higher rate during heating, and the properties of a glass change accordingly. We add to this incompatibility by depressurizing a glass that had been formed by cooling a liquid under a high pressure, p, and then investigate the effects of the added incompatibility by studying thermal conductivity, κ , and the heat capacity per unit volume ρ Cp of the depressurized glass. We use glycerol for the purpose and study first the changes in the features of κ and of ρ Cp during glass formation on cooling under a set of different p. We then partially depressurize the glass and study the effect of the p-induced instability on the features of κ and ρ Cp as the glass is isobarically heated to the liquid state. At a given low p, the glass configuration that was formed by cooling at high-p had a higher κ than the glass configuration that was formed by cooling at a low p. The difference is more when the glass is formed at a higher p and/or is depressurized to a lower p. On heating at a low p, its κ decreases before its glass-liquid transition range is reached. The effect is the opposite of the increase in κ observed on heating a glass at the same p under which it was formed. It is caused by thermally assisted loss of the added incompatibility of configurational and vibrational states of a high-p formed glass kept at low p. If a glass formed under a low-p is pressurized and then heated under high p, it would show the opposite effect, i.e., its κ would first increase to its high p value before its glass-to-liquid transition range.

  2. Sudden bilateral hearing loss after organophosphate inhalation.

    Science.gov (United States)

    Dundar, Mehmet Akif; Derin, Serhan; Aricigil, Mitat; Eryilmaz, Mehmet Akif

    2016-12-01

    Sudden bilateral hearing loss are seen rarely and the toxic substance exposure constitutes a small part of etiology. A Fifty-eight-year-old woman admitted to our clinic with sudden bilateral hearing loss shortly after chlorpyrifos-ethyl exposure. Otolaryngologic examination findings were normal. The patient had 40 dB sensorineural hearing loss (SNHL) on the right ear and 48 dB SNHL on the left ear. Additional diagnostic tests were normal. The conventional treatment for sudden hearing loss was performed. On the second week following organophosphate (OP) exposure the patient's hearing loss almost completely resolved. OP's are heavily used in agriculture and should be taken into consideration as an etiologic factor in sudden hearing loss.

  3. Conformal anomaly around the sudden singularity

    CERN Document Server

    Houndjo, S J M

    2010-01-01

    Quantum effects due to particle creation on a classical sudden singularity have been investigated in a previous work. The conclusion was that quantum effects do not lead to the avoidance nor the modification of the sudden future singularity. In this paper, we investigate quantum corrections coming from conformal anomaly near the sudden future singularity. We conclude that when the equation of state is chosen to be $p=-\\rho-A\\rho^\\alpha$, the conformal anomaly can transform the sudden singularity in the singularity of type III for any $\\alpha> 1/2$ and in the singularity of the type I (the big rip) or the big crunch for $1/2<\\alpha<3/2$.

  4. Conformal anomaly around the sudden singularity

    Science.gov (United States)

    Houndjo, S. J. M.

    2010-10-01

    Quantum effects due to particle creation on a classical sudden singularity have been investigated in a previous work. The conclusion was that quantum effects do not lead to the avoidance nor the modification of the sudden future singularity. In this paper, we investigate quantum corrections coming from conformal anomaly near the sudden future singularity. We conclude that when the equation of state is chosen to be p=-ρ-Aρα, the conformal anomaly can transform the sudden singularity into the singularity of type III for any α>1/2 and into the singularity of the type I (the big rip) or the big crunch for 1/2<α<3/2.

  5. CALVIN'S SUDDEN CONVERSION (SUBITA CONVERSIO) AND ...

    African Journals Online (AJOL)

    CONVERSIO) AND ITS HISTORICAL MEANING. 'COR MEUM TIBI ... Calvin's thought on the sovereignty of God provided the guiding principle for the. Reformed ..... by the Word.26 God, by a sudden conversion, subdued and brought his mind.

  6. Chikungunya virus induced sudden sensorineural hearing loss.

    Science.gov (United States)

    Bhavana, Kranti; Tyagi, Isha; Kapila, Rajeev Kumar

    2008-02-01

    The aim of this study is to demonstrate the association of Chikungunya virus and sudden sensorineural hearing loss. In the case report described we had a case which developed sudden unilateral sensorineural hearing loss following chikungunya fever. A 15-year-old female presented to us with the complains of unilateral sudden onset of hearing loss following an episode of fever, arthralgia and rashes 1 month ago. At the time of these symptoms there were many cases of chikungunya fever in the city, three being in her locality. Clinically Chikungunya fever was suspected and a positive serological test further confirmed our diagnosis. The hearing loss could thus be attributed to Chikungunya virus. Viruses have always been implicated in causing sudden sensorineural hearing loss but Chikungunya virus as a cause has not been documented earlier making this case report a unique one.

  7. Relationship between platelet parameters and sudden ...

    African Journals Online (AJOL)

    Relationship between platelet parameters and sudden sensorineural hearing loss: a ... Data source: A PubMed, Science Direct, Scopus, OVID, EMBASE and ... relationship of PDW and SSNHL but due to the limited studies on this subject more ...

  8. SUDDEN ONSET SENSORINEURAL HEARING LOSS: MANAGEMENT PROTOCOL

    Directory of Open Access Journals (Sweden)

    Anil Kumar

    2016-06-01

    Full Text Available AIMS To study the efficacy of transcutaneous nitroglycerin and pulse steroid injection in patients with sudden hearing loss. MATERIAL AND METHOD This was a prospective study conducted in the Department of ENT, KIMS, Bhubaneswar; 31 patients who fit to inclusion criteria included in this study. RESULTS Out of 31 patients of sudden onset sensorineural hearing loss, 18 (58.06% patients had threshold closer to 30 dB.

  9. The Geometry of Entanglement Sudden Death

    CERN Document Server

    Terra-Cunha, M O

    2007-01-01

    In open quantum systems, entanglement can vanish faster than coherence. This phenomenon is usually called sudden death of entanglement. In this paper sudden death of entanglement is discussed from a geometrical point of view, in the context of two qubits. A classification of possible scenarios is presented, with important known examples classified. Theoretical and experimental construction of other examples is suggested as well as large dimensional and multipartite versions of the effect.

  10. Sudden cardiac death in children and adolescents (excluding Sudden Infant Death Syndrome

    Directory of Open Access Journals (Sweden)

    Gajewski Kelly

    2010-01-01

    Full Text Available Sudden death in the young is rare. About 25% of cases occur during sports. Most young people with sudden cardiac death (SCD have underlying heart disease, with hypertrophic cardiomyopathy and coronary artery anomalies being commonest in most series. Arrhythmogenic right ventricular dysplasia and long QT syndrome are the most common primary arrhythmic causes of SCD. It is estimated that early cardiopulmonary resuscitation and widespread availability of automatic external defibrillators could prevent about a quarter of pediatric sudden deaths.

  11. Surface Electrocardiogram Predictors of Sudden Cardiac Arrest

    Science.gov (United States)

    Abdelghani, Samy A.; Rosenthal, Todd M.; Morin, Daniel P.

    2016-01-01

    Background: Heart disease is a major cause of death in industrialized nations, with approximately 50% of these deaths attributable to sudden cardiac arrest. If patients at high risk for sudden cardiac arrest can be identified, their odds of surviving fatal arrhythmias can be significantly improved through prophylactic implantable cardioverter defibrillator placement. This review summarizes the current knowledge pertaining to surface electrocardiogram (ECG) predictors of sudden cardiac arrest. Methods: We conducted a literature review focused on methods of predicting sudden cardiac arrest through noninvasive electrocardiographic testing. Results: Several electrocardiographic-based methods of risk stratification of sudden cardiac arrest have been studied, including QT prolongation, QRS duration, fragmented QRS complexes, early repolarization, Holter monitoring, heart rate variability, heart rate turbulence, signal-averaged ECG, T wave alternans, and T-peak to T-end. These ECG findings have shown variable effectiveness as screening tools. Conclusion: At this time, no individual ECG finding has been found to be able to adequately stratify patients with regard to risk for sudden cardiac arrest. However, one or more of these candidate surface ECG parameters may become useful components of future multifactorial risk stratification calculators. PMID:27660578

  12. Medulloblastoma manifesting as sudden sensorineural hearing loss.

    Science.gov (United States)

    Terakawa, Yuzo; Tsuyuguchi, Naohiro; Takami, Toshihiro; Ohata, Kenji

    2011-07-01

    We present a rare case of medulloblastoma which presented with unilateral sudden sensorineural hearing loss as an initial symptom. A 19-year-old man was admitted to our hospital with a chief complaint of dizziness and facial numbness on the right side. His illness had begun two years previously with sudden hearing loss on the right side, for which he had been treated as an idiopathic sudden hearing loss. Magnetic resonance imaging demonstrated abnormal signals located mainly in the right middle cerebellar peduncle. We performed partial resection of the tumor by suboccipital craniotomy. The histopathological diagnosis was medulloblastoma. Intrinsic brain tumor is an extremely rare cause of sudden sensorineural hearing loss and is therefore easily overlooked as was in the present case. The present case highlights not only the need to evaluate patients with sudden sensorineural hearing loss by magnetic resonance imaging but also the importance of paying attention to intrinsic lesions involving the brainstem. Although this condition like the presented case might be rare, intrinsic brain tumor should be considered as a potential cause of sudden sensorineural hearing loss, as it may be easily missed leading to a delay in appropriate treatment.

  13. Metabolic disorders prevalence in sudden deafness.

    Science.gov (United States)

    Oiticica, Jeanne; Bittar, Roseli Saraiva Moreira

    2010-01-01

    The aim of the present study was to establish the frequency of metabolic disorders among patients with sudden deafness and to compare this frequency with data from population surveys. No consensus has been reached regarding the prevalence of metabolic disorders among sudden deafness patients or their influence as associated risk factors. This cross-sectional study enrolled all sudden deafness patients treated in the Otolaryngology Department of the University of São Paulo between January 1996 and December 2006. Patients were subjected to laboratory exams including glucose and cholesterol levels, low-density lipoprotein cholesterol fraction, triglycerides, free T4 and TSH. The sample comprised 166 patients. We observed normal glucose levels in 101 (81.5%) patients and hyperglycemia in 23 (18.5%) patients, which is significantly different (p sudden hearing loss patients and the Brazilian population. Normal levels of thyroid hormones were observed in 116 patients (78.4%), and abnormal levels were observed in 32 (21.6%) patients. Compared with the prevalence of thyroid disorders in the general population (10%), statistical analysis revealed a significant difference (p = 0.0132) between these two groups. Among sudden deafness patients, we observed frequencies of hyperglycemia and thyroid disorders that were more than twice those of the general population. Hyperglycemia and thyroid disorders are much more frequent in patients with sudden deafness than in the general population and should be considered as important associated risk factors.

  14. Secondary endolymphatic hydrops after sudden deafness.

    Science.gov (United States)

    Cho, Tsung-Yi; Cheng, Po-Wen; Young, Yi-Ho

    2013-10-01

    Patients with sudden deafness who had abnormal ocular vestibular-evoked myogenic potential (oVEMP)/cervical VEMP (cVEMP) responses but retained caloric function may subsequently develop secondary hydrops with a mean interval of 8 years. This study applied the inner ear test battery in patients who had sudden deafness previously to elucidate how secondary endolymphatic hydrops occurs years after sudden deafness. Twenty patients who had experienced recent vertiginous attacks several years after sudden deafness (group A) and 20 patients without rotational vertiginous episode for at least 5 years following sudden deafness (group B) were enrolled. All patients underwent an inner ear test battery comprising audiometry, caloric test, and oVEMP and cVEMP tests. The mean interval from initial sudden deafness to vertiginous attack in group A was 8 years, with a mean hearing level of 66 ± 20 dB, which did not significantly differ from 61 ± 20 dB in group B. For the vestibular test results, the percentages of abnormal cVEMP, oVEMP, and caloric tests in group A were 65%, 70%, and 25%, respectively. Compared to the respective 70%, 60%, and 75% abnormalities in group B, only the caloric test differed significantly.

  15. A nudged chemistry-climate model simulation of chemical constituent distribution at northern high-latitude stratosphere observed by SMILES and MLS during the 2009/2010 stratospheric sudden warming

    Science.gov (United States)

    Akiyoshi, H.; Nakamura, T.; Miyasaka, T.; Shiotani, M.; Suzuki, M.

    2016-02-01

    Stratospheric sudden warming (SSW) is a dramatic phenomenon of the winter stratosphere in which the distribution of chemical constituents, associated chemical tendency, and transport of chemical constituents differ significantly inside and outside of the polar vortex. In this study, the chemical constituent distributions in the major SSW of 2009/2010 were simulated by the Model for Interdisciplinary Research on Climate 3.2-Chemistry-Climate Model (CCM) nudged toward the European Center for Medium-Range Weather Forecasts-Interim Re-Analysis data. The results were compared with Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) and Microwave Limb Sounder (MLS) observations. In addition, ozone tendency due to ozone transport and chemical ozone loss in the high-latitude lower stratosphere before and after the SSW was analyzed for the period from 1 January 2010 to 11 February 2010. The evolution and distribution of ozone and HCl inside/outside the polar vortex associated with the vortex shift to the midlatitudes in January are quite similar between SMILES and MLS. Those of ClO are also similar, considering the difference in the local time for the measurement. Analyses of the nudged CCM run indicate that inside the polar vortex at 50 hPa, the ozone concentration increased moderately owing to partial cancelation between the large negative ozone tendency due to chemical ozone destruction and large positive ozone tendency due to horizontal ozone influx from outside of the vortex as well as downward advection. In the region of a high ozone concentration with the same area as that of the polar vortex at 50 hPa, the large increase in ozone was primarily due to a downward advection of ozone. SMILES and MLS observations, nudged CCM simulations, and ozone tendency analyses revealed a highly longitudinal dependent ozone tendency at high latitudes during the SSW.

  16. The Seasonal Timing of Stratospheric Sudden Warmings

    Science.gov (United States)

    Horan, Matthew; Reichler, Thomas

    2017-04-01

    We aim to diagnose causes for the differences in the seasonal distribution of stratospheric sudden warmings (SSWs) between reanalysis and models. Observations over the past 60 years indicate that most SSWs occur during mid-winter (January), but climate models tend to simulate the maximum number of SSWs during late-winter or early-spring. This discrepancy has led to the speculation that models might be flawed and that the simulation of a January maximum represents a measure of model performance. However, the relatively short observational record and rare occurrence of SSWs also implies considerable uncertainty in the observation derived result. The goal of this work is to understand the seasonal distribution of SSWs using a simple statistical model, to test the model using a variety of data sets, and to answer the questions when SSWs are most likely to occur and what the reasons for it are. Our analysis is based on Charlton and Polvani's (2007) criteria for SSWs and on the assumption that the polar vortex wind approximately follows a normal distribution. The statistical model successfully predicts the day-to-day variations in the empirically derived occurrence frequency of SSWs, demonstrating that the seasonal distribution of SSWs can be almost entirely understood in terms of the climatological seasonal cycle of the polar vortex wind. The statistical model indicates that the maximum frequency of SSWs in climate models and reanalysis occurs during late-winter, and not during mid-winter as implied by the observations. This strongly suggests that sampling uncertainty is responsible for the January maximum seen in the reanalysis and that the simulation of a January maximum does not represent a metric of model performance. The reason for the late-winter maximum is the decreasing strength of the polar vortex, making it more likely that the winds of the polar vortex reach the zero-threshold required by the WMO definition for SSWs. This further suggests that climatological

  17. Simulation of Theoretical Most-Extreme Geomagnetic Sudden Commencements

    Science.gov (United States)

    Welling, Daniel; Love, Jeffrey; Wiltberger, Michael; Rigler, Erin; Gombosi, Tamas

    2016-04-01

    We report results from a numerical simulation of geomagnetic sudden commencements driven by solar wind conditions given by theoretical-limit extreme coronal-mass ejections (CMEs) estimated by Tsurutani and Lakhina [2014]. The CME characteristics at Earth are a step function that jumps from typical quiet values to 2700 km/s flow speed and a magnetic field magnitude of 127 nT. These values are used to drive three coupled models: a global magnetohydrodynamic (MHD) magnetospheric model (BATS-R-US), a ring current model (the Rice Convection Model, RCM), and a height-integrated ionospheric electrodynamics model (the Ridley Ionosphere Model, RIM), all coupled together using the Space Weather Modeling Framework (SWMF). Additionally, simulations from the Lyon-Fedder-Mobarry MHD model are performed for comparison. The commencement is simulated with both purely northward and southward IMF orientations. Low-latitude ground-level geomagnetic variations, both B and dB/dt, are estimated in response to the storm sudden commencement. For a northward interplanetary magnetic field (IMF) storm, the combined models predict a maximum sudden commencement response, Dst-equivalent of +200 nT and a maximum local dB/dt of ~200nT/s. While this positive Dst response is driven mainly by magnetopause currents, complicated and dynamic Birkeland current patterns also develop, which drive the strong dB/dt responses at high latitude. For southward IMF conditions, erosion of dayside magnetic flux allows magnetopause currents to approach much closer to the Earth, leading to a stronger terrestrial response (Dst-equivalent of +250 nT). Further, high latitude signals from Region 1 Birkeland currents move to lower latitudes during the southward IMF case, increasing the risk to populated areas around the globe. Results inform fundamental understanding of solar-terrestrial interaction and benchmark estimates for induction hazards of interest to the electric-power grid industry.

  18. Serum Magnesium and Sudden Death in European Hemodialysis Patients.

    Directory of Open Access Journals (Sweden)

    Camiel L M de Roij van Zuijdewijn

    Full Text Available Despite suggestions that higher serum magnesium (Mg levels are associated with improved outcome, the association with mortality in European hemodialysis (HD patients has only scarcely been investigated. Furthermore, data on the association between serum Mg and sudden death in this patient group is limited. Therefore, we evaluated Mg in a post-hoc analysis using pooled data from the CONvective TRAnsport STudy (CONTRAST, NCT00205556, a randomized controlled trial (RCT evaluating the survival risk in dialysis patients on hemodiafiltration (HDF compared to HD with a mean follow-up of 3.1 years. Serum Mg was measured at baseline and 6, 12, 24 and 36 months thereafter. Cox proportional hazards models, adjusted for confounders using inverse probability weighting, were used to estimate hazard ratios (HRs of baseline serum Mg on all-cause mortality, cardiovascular mortality, non-cardiovascular mortality and sudden death. A generalized linear mixed model was used to investigate Mg levels over time. Out of 714 randomized patients, a representative subset of 365 (51% were analyzed in the present study. For every increase in baseline serum Mg of 0.1 mmol/L, the HR for all-cause mortality was 0.85 (95% CI 0.77-94, the HR for cardiovascular mortality 0.73 (95% CI 0.62-0.85 and for sudden death 0.76 (95% CI 0.62-0.93. These findings did not alter after extensive correction for potential confounders, including treatment modality. Importantly, no interaction was found between serum phosphate and serum Mg. Baseline serum Mg was not related to non-cardiovascular mortality. Mg decreased slightly but statistically significant over time (Δ -0.011 mmol/L/year, 95% CI -0.017 to -0.009, p = 0.03. In short, serum Mg has a strong, independent association with all-cause mortality, cardiovascular mortality and sudden death in European HD patients. Serum Mg levels decrease slightly over time.

  19. Histological Findings in Unclassified Sudden Infant Death, Including Sudden Infant Death Syndrome

    NARCIS (Netherlands)

    Liebrechts-Akkerman, Germaine; Bovee, Judith V. M. G.; Wijnaendts, Liliane C. D.; Maes, Ann; Nikkels, Peter G. J.; de Krijger, Ronald R.

    2013-01-01

    Our objective was to study histological variations and abnormalities in unclassified sudden infant death (USID), including sudden infant death syndrome (SIDS), in The Netherlands. Two hundred Dutch USID cases between 1984 and 2005 were identified. The histology slides and autopsy reports of 187 case

  20. Histological findings in unclassified sudden infant death, including sudden infant death syndrome

    NARCIS (Netherlands)

    G. Liebrechts-Akkerman (Germaine); J.V.M.G. Bovée (Judith V. M. G.); L.C.D. Wijnaendts (Liliane); A. Maes (Ann); P.G.J. Nikkels (Peter); R.R. de Krijger (Ronald)

    2013-01-01

    textabstractOur objective was to study histological variations and abnormalities in unclassified sudden infant death (USID), including sudden infant death syndrome (SIDS), in The Netherlands. Two hundred Dutch USID cases between 1984 and 2005 were identified. The histology slides and autopsy reports

  1. Sudden death syndrome – An overview

    Directory of Open Access Journals (Sweden)

    M. F. M. F. Siddiqui

    Full Text Available Metabolic disorders affect internal body metabolism and development and are the cause of the large proportion of mortality in both commercial and backyard poultry flocks. One of the main factor affecting these diseases is rapid growth rate. Two of the more important types of metabolic disorders are the “Sudden Death Syndrome” and Ascites. Sudden death syndrome (SDS is a condition in which apparently healthy fast growing broilers chicks die suddenly from no apparent causes. There is usually a short wing beating convulsions prior to death, so that the majority of affected broilers are found dead lying on their backs. As a result, the condition often been referred to as “Flip-Over Disease”. Sudden death syndrome has developed into a major problem to the broiler industry in many parts of the world. Broilers of all ages are affected starting as early as 2 days of age and continuing through to market age. Peak mortality usually occurs between 3 and 4 weeks of age. Males are more affected than the females. Lung edema is a prominent PM lesions.There is no proper treatment and preventive measures for control of SDS, but incidence can be reduced by management techniques. The causes of the Sudden Death Syndrome includes; Managemental factors, Nutritional factors, Diet Composition and Role of Prostaglandins. [Vet World 2009; 2(11.000: 444-447

  2. SOCCER RELATED SUDDEN DEATHS IN TURKEY

    Directory of Open Access Journals (Sweden)

    Çağlar Özdemir

    2008-06-01

    Full Text Available Regular physical exercise is recommended by the medical community, because it offers the potential to reduce the incidence of coronary events. On the other hand, vigorous exertion may act as a trigger of acute myocardial infarction and sudden cardiac death in susceptible individuals. Death during sports activities differs among sports disciplines and countries. In Turkey, soccer attracts more spectators than any other sports activity and the attention of the press and media, and is preferred over other sports by many young and middle-aged individuals. As autopsy-based studies are infrequent in literature and there is a lack of data detailing sudden death during physical activity in Turkey, we present a Turkish series of sudden deaths that occurred during soccer games based on data provided by the Morgue Specialization Department of the Council of Forensic Medicine. We identified 15 male cases of soccer-related sudden death aged from 10 to 48 years. Coronary artery disease was identified as the cause of sudden death in 11 cases

  3. Equilibrium and Sudden Events in Chemical Evolution

    Science.gov (United States)

    Weinberg, David H.; Andrews, Brett H.; Freudenburg, Jenna

    2017-03-01

    We present new analytic solutions for one-zone (fully mixed) chemical evolution models that incorporate a realistic delay time distribution for Type Ia supernovae (SNe Ia) and can therefore track the separate evolution of α-elements produced by core collapse supernovae (CCSNe) and iron peak elements synthesized in both CCSNe and SNe Ia. Our solutions allow constant, exponential, or linear–exponential ({{te}}-t/{τ {sfh}}) star formation histories, or combinations thereof. In generic cases, α and iron abundances evolve to an equilibrium at which element production is balanced by metal consumption and gas dilution, instead of continuing to increase over time. The equilibrium absolute abundances depend principally on supernova yields and the outflow mass loading parameter η, while the equilibrium abundance ratio [α /{Fe}] depends mainly on yields and secondarily on star formation history. A stellar population can be metal-poor either because it has not yet evolved to equilibrium or because high outflow efficiency makes the equilibrium abundance itself low. Systems with ongoing gas accretion develop metallicity distribution functions (MDFs) that are sharply peaked, while “gas starved” systems with rapidly declining star formation, such as the conventional “closed box” model, have broadly peaked MDFs. A burst of star formation that consumes a significant fraction of a system’s available gas and retains its metals can temporarily boost [α /{Fe}] by 0.1–0.3 dex, a possible origin for rare, α-enhanced stars with intermediate age and/or high metallicity. Other sudden transitions in system properties can produce surprising behavior, including backward evolution of a stellar population from high to low metallicity.

  4. EFFORT ADAPTATION OR SUDDEN CARDIAC DEATH?

    Directory of Open Access Journals (Sweden)

    Musat Carmina Liana

    2009-12-01

    Full Text Available During training processes, the human body gradually adapts itself, yet it is hard to believe that it has beenconceived in such way that it could endure the conditions of winning a modern Olympic or world medal. Withrespect to the physical effort, there is the following paradox: if the physical effort is acknowledged as a protector of the heart on the long term, then what causes these sports-related conditions that may result in sudden death?Thus arises the necessity of tracking and evaluating the cardiovascular risk targeting the professional sportsmen, their EKG fluctuations, the cardiovascular causes of sudden death, the part played by the physician and the sportsman in preventing the sudden death, as well as numerous clinical cases of sports cardiology

  5. Sudden unexpected death in infancy in Denmark

    DEFF Research Database (Denmark)

    Winkel, Bo Gregers; Holst, Anders Gaarsdal; Theilade, Juliane;

    2011-01-01

    Abstract Background. Incidence of sudden unexpected death in infancy (SUDI) and sudden infant death syndrome (SIDS) differs among studies and non-autopsied cases are difficult to assess. Objectives. To investigate causes of sudden death in infancy in a nationwide setting. Validate the use...... of the ICD-10 code for SIDS (R95) in the Danish Cause of Death registry. Design. A retrospective analysis of all infant deaths (death certificates and autopsy reports were read. Results. We identified 192 SUDI cases (10% of total deaths, 0.42 per 1000 births......) with autopsy performed in 87% of cases. In total, 49% of autopsied SUDI cases were defined as SIDS (5% of all deaths, 0.22 per 1000 births); Cardiac cause of death was denoted in 24% of cases. The Danish Cause of Death Registry misclassified 30% of SIDS cases. Conclusions. A large proportion of infant deaths...

  6. Metabolic disorders prevalence in sudden deafness

    Directory of Open Access Journals (Sweden)

    Jeanne Oiticica

    2010-01-01

    Full Text Available OBJECTIVES: The aim of the present study was to establish the frequency of metabolic disorders among patients with sudden deafness and to compare this frequency with data from population surveys. INTRODUCTION: No consensus has been reached regarding the prevalence of metabolic disorders among sudden deafness patients or their influence as associated risk factors. METHODS: This cross-sectional study enrolled all sudden deafness patients treated in the Otolaryngology Department of the University of São Paulo between January 1996 and December 2006. Patients were subjected to laboratory exams including glucose and cholesterol levels, low-density lipoprotein cholesterol fraction, triglycerides, free T4 and TSH. RESULTS: The sample comprised 166 patients. We observed normal glucose levels in 101 (81.5% patients and hyperglycemia in 23 (18.5% patients, which is significantly different (p < 0.0001 compared to the diabetes mellitus prevalence (7.6% in the Brazilian population. Cholesterol levels were normal in 78 patients (49.7% and abnormal in 79 (50.3% patients, which is significantly different compared to the Brazilian population (p = 0.0093. However, no differences were observed in low-density lipoprotein cholesterol fraction (p = 0.1087 or triglyceride levels (p = 0.1474 between sudden hearing loss patients and the Brazilian population. Normal levels of thyroid hormones were observed in 116 patients (78.4%, and abnormal levels were observed in 32 (21.6% patients. Compared with the prevalence of thyroid disorders in the general population (10%, statistical analysis revealed a significant difference (p = 0.0132 between these two groups. DISCUSSION: Among sudden deafness patients, we observed frequencies of hyperglycemia and thyroid disorders that were more than twice those of the general population. CONCLUSIONS: Hyperglycemia and thyroid disorders are much more frequent in patients with sudden deafness than in the general population and should be

  7. Update on the sudden hearing loss

    OpenAIRE

    Federica Bullo; Spyridon Tzamtzis; Giancarlo Tirelli

    2013-01-01

    Aims: Sudden hearing loss is defined as a sensory neural hearing deafness of at least 30 dB in three consecutive speech frequencies that as occurred within the 3 days. It is a medical emergency and the treatment should start as soon as possible; up to now therapies are empirically addressed to improve hearing. Materials and Methods: We have evaluated 558 patients with a diagnosis of sudden hearing loss. In our study, we have investigated possible prognostic factors of hearing loss and their i...

  8. Sudden Infant Death Syndrome with Harlequin Fetus

    Directory of Open Access Journals (Sweden)

    Selahattin Katar

    2007-01-01

    Full Text Available The harlequin fetus, a severe variant of ichthyosis, occurs rarely, and these babies die within the first few days of life. Early retinoid therapy may improve the disorder and help increase survival rates. The exact cause of the sudden infant death syndrome of the suckling is not known and the incidence approximately is 0.1-0.3 %. In general, these babies looked well and healthy at the time of the sleeping but were found dead in their bed in the morning. We report a harlequin fetus with sudden infant death syndrome.

  9. Undiagnosed intracranial lipoma associated with sudden death

    Directory of Open Access Journals (Sweden)

    Carlos Durão

    2017-03-01

    Full Text Available Intracranial lipomas represent less than 0.1% of all intracranial tumors. They are usually located in the callus area and often asymptomatic. This paper presents a sudden death case after an episode of convulsions on a 39 years old woman with a history of migraines and seizures since adolescence. The autopsy revealed the presence of an undiagnosed massive brain lipoma (60 × 35 mm associated with atrophy of the corpus callosum. Although very rare and seldom malignant these may be associated with seizures and sudden death.

  10. Autologistic model with an application to the citrus "sudden death" disease Modelo autologístico com aplicação para a doença "morte súbita" dos citrus

    Directory of Open Access Journals (Sweden)

    Elias Teixeira Krainski

    2008-01-01

    Full Text Available The citrus sudden death (CSD disease affects dramatically citrus trees causing a progressive plant decline and death. The disease has been identified in the late 90's in the main citrus production area of Brazil and since then there are efforts to understand the etiology as well as the mechanisms its spreading. One relevant aspect of such studies is to investigate spatial patterns of the occurrence within a field. Methods for determining whether the spatial pattern is aggregated or not has been frequently used. However it is possible to further explore and describe the data by means of adopting an explicit model to discriminate and quantify effects by attaching parameters to covariates which represent aspects of interest to be investigated. One alternative involves autologistic models, which extend a usual logistic model in order to accommodate spatial effects. In order to implement such model it is necessary to take into account the reuse of data to built spatial covariates, which requires extensions in methodology and algorithms to assess the variance of the estimates. This work presents an application of the autologistic model to data collected at 11 time points from citrus fields affected by CSD. It is shown how the autologistic model is suitable to investigate diseases of this type, as well as a description of the model and the computational aspects necessary for model fitting.A morte súbita dos citros (MSC é uma doença com efeitos dramáticos em árvores de citros causando declínio progressivo e morte. Ela foi identificada no final da década de 90 em uma das principais áreas de produção no Brasil e desde então esforços são empregados para entender a sua etiologia e os seus mecanismos de dispersão. Um aspecto relevante para estudos é a investigação do padrão espacial da incidência dentro de um campo. Métodos para determinar se o padrão espacial é agregado ou não têm sido freqüentemente utilizados. Entretanto é poss

  11. Systemic Steroid Application Caused Sudden Death of a Patient with Sudden Deafness

    Directory of Open Access Journals (Sweden)

    Eriko Ogino-Nishimura

    2013-01-01

    Full Text Available A 63-year-old man, who was diagnosed with sudden sensorineural hearing loss (SSHL, showed severe hypertension 10 hours after prednisolone administration. Subsequently, the patient suddenly died due to pulmonary edema. The autopsy indicated a pheochromocytoma in the right adrenal gland, and the cause of death was determined to be a pheochromocytoma crisis induced by systemic administration of prednisolone. Pheochromocytoma crisis is a life-threatening condition and can result from the use of corticosteroids. Physicians should consider the risk of a pheochromocytoma crisis due to systemic corticosteroids in the treatment of patients with sudden sensorineural hearing loss.

  12. Sudden cardiac death in young adults

    DEFF Research Database (Denmark)

    Larsen, Maiken K; Nissen, Peter H; Kristensen, Ingrid B;

    2012-01-01

    Familial hypercholesterolemia (FH) is a genetic disorder that may lead to premature coronary heart disease (CHD) and sudden cardiac death (SCD). Mutations in the LDLR or APOB genes cause FH. We have screened the LDLR and the ligand-binding region of APOB genes in 52 cases of SCD. Deceased patients...... premature CHD and SCD....

  13. Update on the sudden hearing loss

    Directory of Open Access Journals (Sweden)

    Federica Bullo

    2013-01-01

    Full Text Available Aims: Sudden hearing loss is defined as a sensory neural hearing deafness of at least 30 dB in three consecutive speech frequencies that as occurred within the 3 days. It is a medical emergency and the treatment should start as soon as possible; up to now therapies are empirically addressed to improve hearing. Materials and Methods: We have evaluated 558 patients with a diagnosis of sudden hearing loss. In our study, we have investigated possible prognostic factors of hearing loss and their influence on the recovery of the pathology. Results and Discussion: Sudden hearing loss requires an immediate therapeutic intervention. The corticosteroid therapy remains the most accredited one at which are reported the most satisfactory results. We have recognized as negative prognostic factors hearing loss on acute frequencies in the audiometric exam, the presence of a severe-deep hearing loss and a delay in starting therapy. Conclusion: The sudden hearing loss is an otologic emergency which requires an immediate therapeutic intervention. The most accredited therapy remains the corticosteroid therapy. Frequencies we have recognized as negative prognostic factors hearing loss on acute frequencies. The presence of a severe-deep hearing loss, and a delay in starting therapy.

  14. Sudden (reversible) sensorineural hearing loss in pregnancy.

    LENUS (Irish Health Repository)

    Kenny, R

    2011-03-01

    Sudden hearing loss directly associated with pregnancy or birth is a little known and rare occurrence. The temporary, unilateral, low-frequency sensorineural hearing loss in this case was reported after the birth of the patient\\'s first child, and again during the third trimester of her second pregnancy.

  15. Alcohol Use and Sudden Infant Death Syndrome

    Science.gov (United States)

    Friend, Karen B.; Goodwin, Matthew S.; Lipsitt, Lewis P.

    2004-01-01

    Despite general evidence of fetal toxicities associated with sudden infant death syndrome (SIDS), there has been limited research focusing on the effects of parental alcohol use on SIDS occurrence, either directly or in interaction with other risk conditions. The purpose of this paper is to review the literature on parental, especially maternal,…

  16. Sudden death syndrome of soybean in Argentina

    Science.gov (United States)

    Sudden death syndrome (SDS) is one of the most common and widely spread root disease affecting soybean [Glycine max (L.) Merr.] in Argentina where it is an economically important crop. This disease was first discovered in this country in 1992 in the Pampas Region, and the following year in Northwest...

  17. Sudden Deafness during Antepartum versus Postpartum Periods.

    Science.gov (United States)

    Zhang, Bang-Yan; Young, Yi-Ho

    2017-10-06

    This study reviewed our experience in treating sudden deafness in antepartum (pregnant) and postpartum women during the past 2 decades. From 1997 to 2016, we have recorded sudden deafness in 16 antepartum (mean age, 32 years) and 3 postpartum (mean age, 31 years) women. Sudden deafness occurred during the 1st, 2nd, and 3rd trimesters in 5, 4, and 7 antepartum women, respectively. In contrast, the mean interval between giving birth and symptom onset in the 3 postpartum women was 18 days. Each patient underwent an inner ear test battery. In 8 antepartum women treated by dextran infusion, the outcome as regards hearing was improved in 7 patients (88%) and unchanged in 1 patient. In contrast, the other 8 antepartum women selected no treatment, and only 1 patient (12%) achieved hearing improvement, exhibiting a significantly better outcome when receiving dextran treatment. For the postpartum women, 2 patients had hearing improvement when treated by antioxidants, while 1 patient retained unchanged hearing without treatment. Medication is needed in sudden deafness in antepartum or postpartum women rather than waiting for a natural course. No adverse effects have been identified in any of the mothers or offspring 1 year after delivery. © 2017 S. Karger AG, Basel.

  18. Febrile convulsions and sudden infant death syndrome

    DEFF Research Database (Denmark)

    Vestergaard, Mogens; Basso, Olga; Henriksen, Tine Brink

    2002-01-01

    It has been suggested that sudden infant death syndrome (SIDS) and febrile convulsions are related aetiologically. We compared the risk of SIDS in 9877 siblings of children who had had febrile convulsions with that of 20.177 siblings of children who had never had febrile convulsions. We found...

  19. Sudden gains in two psychotherapies for posttraumatic stress disorder.

    Science.gov (United States)

    König, Julia; Karl, Regina; Rosner, Rita; Butollo, Willi

    2014-09-01

    We examined sudden, large, and stable shifts in symptoms from one therapy session to the next in two treatments for posttraumatic stress disorder (PTSD). Shifts in a positive direction (sudden gains) have so far been more frequently analyzed than those in a negative direction (sudden losses). We analyzed data from 102 outpatients suffering from PTSD who received either a cognitive-behavioral or a Gestalt-based intervention. Sudden gains, at 22.5%, were more frequent than sudden losses (3.9% of patients). Participants who had experienced sudden gains had lower PTSD scores at posttreatment, but not at the 6-month follow-up. As sudden losses were so rare, they were not analyzed statistically. Sudden gains accounted for 52% of overall treatment gains or 26% of overall change in a positive direction. Among very successful patients, those with sudden gains were overrepresented, but in absolute terms, there were as many patients without sudden gains in this group. There was no connection between sudden gains and type of intervention or depressive symptoms. Sudden gains and sudden losses occurred in our sample of PTSD patients, but in the light of current results, their clinical importance seems to be limited.

  20. [EPIDEMIOLOGY OF SUDDEN CARDIAC DEATH: DATA FROM THE PARIS SUDDEN DEATH EXPERTISE CENTER REGISTRY].

    Science.gov (United States)

    Jouven, Xavier; Bougouin, Wulfran; Karam, Nicole; Marijon, Eloi

    2015-09-01

    Sudden cardiac death is an unexpected cardiac arrest without obvious extra-cardiac cause. Epidemiology of sudden cardiac death has been poorly documented in France, mainly because of challenging requirement in order to capture all cases in a specific area. The Parisian registry (Sudden Death Expertise Center, European Georges Pompidou Hospital, Paris) was initiated in May 2011 and analyzed data of all sudden death in Paris and suburbs (6.6 millions inhabitants). Over 3 years, the annual incidence estimated to 50-70 per 100,000. Those occurred mainly in men (69%), with a mean age of 65 year, and at home (75%). The event was witnessed in 80% of cases, but bystander cardiopulmonary resuscitation was initiated in only half of cases. Initial cardiac rhythm was ventricular fibrillation in 25%. Survival to hospital discharge remains low (8%).

  1. A Case of Sudden Deafness with Intralabyrinthine Hemorrhage Intralabyrinthine Hemorrhage and Sudden Deafness

    National Research Council Canada - National Science Library

    Park, Jeong Jin; Jeong, Se Won; Lee, Jae Wook; Han, Su-Jin

    2015-01-01

    .... The prognosis SSNHL by intralabyrintine hemorrhage is generally known to be poor. We report a case of sudden deafness with intralabyrintine hemorrhage who has a history of anticoagulant administration, with a review of literature.

  2. An Experimental Study on Flow Boiling Critical Heat Flux Characteristics of Suddenly Expanded Region

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Jin; Song, Sub Lee; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Moon, Sang Ki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    In this experiment, test section has been designed to simulate sudden flow path change due to deformation of cladding. It was tended to simulate cladding deformation that has discontinuous diameter change so coolant flow path changes suddenly. Experiments are in progress. Experiments on test section that simulate deformed flow path which contains sudden contraction and sudden expansion part have been done. Location of CHF has been varied by different condition of experiment. CHF at the outlet of test section fits well into the Macbeth's correlation and data of reference experiment, which was held on plain test section that had same diameter with inlet diameter of deformed test section. CHF at sudden expansion part was in churn flow regime and CHF was very low compared to expectation. It is discussed that liquid film separation from wall or bubble accumulation by backflow might be the reason of this result. For future work, experiments for two additional blockage ratio conditions will be carried out. Also, discussion and model development for deformed channel with sudden expand flow path will be held on.

  3. Evolution of IPv6 Internet topology with unusual sudden changes

    Institute of Scientific and Technical Information of China (English)

    Ai Jun; Zhao Hai; Kathleen M.Carley; Su Zhan; Li Hui

    2013-01-01

    The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes.Consequently,identifying patterns of unusual topology evolution is critical for Internet topology modeling and simulation.We analyze IPv6 Internet topology evolution in IP-level graph to demonstrate how it changes in uncommon ways to restructure the Internet.After evaluating the changes of average degree,average path length,and some other metrics over time,we find that in the case of a large-scale growing the Internet becomes more robust; whereas in a top-bottom connection enhancement the Internet maintains its efficiency with links largely decreased.

  4. Nonlocality Sudden Birth and Transfer in System and Environment

    Institute of Scientific and Technical Information of China (English)

    QIU Liang

    2011-01-01

    Dynamics of the nonlocality measured by the violation of Svetlichny's Bell-type inequality is investigated in the non-Markovian model. The phenomenon of nonlocality sudden birth for the atoms and the reservoirs is obtained.The evolution of the nonlocality among the atoms or the reservoirs depends on the choice of the atom detuning from the cavity pseudomode, the cavity pseudomode decay and the rotation angles. For the small pseudomode decay in the near-resonance regime, the initial atomic nonlocality is completely transferred to the reservoirs ultimately.

  5. Evolution of IPv6 Internet topology with unusual sudden changes

    Science.gov (United States)

    Ai, Jun; Zhao, Hai; Kathleen, M. Carley; Su, Zhan; Li, Hui

    2013-07-01

    The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes. Consequently, identifying patterns of unusual topology evolution is critical for Internet topology modeling and simulation. We analyze IPv6 Internet topology evolution in IP-level graph to demonstrate how it changes in uncommon ways to restructure the Internet. After evaluating the changes of average degree, average path length, and some other metrics over time, we find that in the case of a large-scale growing the Internet becomes more robust; whereas in a top—bottom connection enhancement the Internet maintains its efficiency with links largely decreased.

  6. Sudden eruption of multiple Meyerson naevi

    Directory of Open Access Journals (Sweden)

    Sandra Jerkovic Gulin

    2017-03-01

    Full Text Available We present a case of a young patient presenting with a six-month history of multiple squamous pink and light brown papules surrounded by symmetrical eczema on the trunk. Dermoscopy revealed light brown structureless and avascular lesions with an erythematous scaly halo. The patient denied the presence of naevi on the sites of the newly emerging changes. Histopathology revealed acanthotic epidermis and linear clusters of morphologically normal naevi cells in the upper dermis, infiltration of lymphocytes, plasma cells, eosinophils and mild spongiosis in the  dermis. Topical betamethasone/gentamicin ointment twice daily for 10 days was prescribed. The erythematous scaly area around lesions completely disappeared on the follow-up visit after six months. This is a unique case of a sudden appearance of newly formed multiple benign dermal naevi with Meyerson phenomenon—the sudden eruption of multiple Meyerson naevi.

  7. Sudden Sensorineural Hearing Loss; Prognostic Factors

    Directory of Open Access Journals (Sweden)

    Arjun Dass

    2015-09-01

    Full Text Available Introduction: Sudden sensorineural hearing loss (SSNHL is a frightening and frustrating symptom for the patient as well as the physician. Prognosis is affected by multiple factors including duration of hearing loss, presence of associated vertigo and tinnitus, and co-morbidities such as hypertension and diabetes.   Materials and Methods: Forty subjects presenting to our department with features of sudden hearing loss were included in the study. Detailed otological history and examination, serial audiometric findings and course of disease were studied.   Results: Subjects presenting late (in older age, having associated vertigo, hypertension and diabetes had a significantly lower rate of recovery.   Conclusion:  Only 60–65% of patients experiencing SSNHL recover within a period of 1 month; this rate is further affected by presence of multiple prognostic indicators.

  8. Rare cause of bilateral sudden deafness.

    Science.gov (United States)

    Vos, F I; Merkus, P; van Nieuwkerk, E B J; Hensen, E F

    2016-10-08

    In this paper, we describe the case of a 62-year-old female with recurring episodes of sudden deafness with vertigo and facial paresis. Within a month's time, this resulted in bilateral deafness and vestibular areflexia. Erroneously, the patient was diagnosed with sudden deafness of unknown origin and subsequently with neuroborreliosis (Lyme disease). The true diagnosis of relapsing polychondritis (RP) was revealed 9 months after initial presentation. The diagnostic delay is in part explained by the fact that, by definition, the disease has to relapse before the diagnosis can be made, but also by its pluriform clinical presentation. Timely identification of RP as the cause of this profound sensorineural hearing loss proved to be important. It was key in instigating adequate follow-up, and allowed for cochlear implantation before total cochlear obliteration, which might have hampered optimal hearing rehabilitation.

  9. Arachnoid Cyst Presenting With Sudden Hearing Loss

    Directory of Open Access Journals (Sweden)

    Hsuan-Ho Chen

    2010-06-01

    Full Text Available Arachnoid cysts can occur at different intracranial sites, including the cerebellopontine angle (CPA. They often occur in childhood, in the posterior fossa. They may present with symptoms such as dizziness, tinnitus and hearing loss, or they may be asymptomatic. Presentation with sudden deafness is very rare. We report the unusual presentation of a 67-year-old male with CPA arachnoid cyst and the complaint of sudden-onset deafness. In this case, the cystic lesion at the CPA was found by magnetic resonance imaging of the brain. Pathology after retromastoid suboccipital craniotomy confirmed an arachnoid cyst. The treatment of this patient is discussed and the possible causes of CPA arachnoid cyst are briefly reviewed.

  10. Diclofenac induced sudden sensorineural hearing loss

    OpenAIRE

    M Bhanukumar; Vineetha Bharathan Menon; Justin Kurian; Madhan Ramesh

    2015-01-01

    A few cases of mild to moderate, gradual and reversible sensorineural hearing loss (SNHL) with prolonged doses of nonsteroidal anti-inflammatory drugs has been reported. We present a case of sudden irreversible SNHL in a 60-year-old female after taking a single dose of diclofenac. The patient was a known case of diabetes mellitus and hypertension and was on regular treatment. We postulate that the patient's hearing loss was the result of diclofenac's ototoxic effects which may have been poten...

  11. Cognitive impairment after sudden cardiac arrest

    OpenAIRE

    Jaszke-Psonka, Magdalena; Piegza, Magdalena; Ścisło, Piotr; Pudlo, Robert; Piegza, Jacek; Badura-Brzoza, Karina; Leksowska, Aleksandra; Hese, Robert T.; Gorczyca, Piotr W.

    2016-01-01

    Aim To evaluate the incidence and severity of the impairment of selected cognitive functions in patients after sudden cardiac arrest (SCA) in comparison to patients after myocardial infarction without SCA and healthy subjects and to analyze the influence of sociodemographic and clinical parameters and the duration of cardiac arrest on the presence and severity of the described disorders. Material and methods The study group comprised 30 cardiac arrest survivors, the reference group comprised ...

  12. Sudden cardiac death in the elite athlete.

    Science.gov (United States)

    Del Rio-santiago, Valentín; Santiago Trinidad, Ricardo; Vicenty Rivera, Sonia

    2012-01-01

    Sudden cardiac death (SCD) is a long -recognized disease that occurs rarely in trained athletes. Most affected athletes have no symptoms before death. Many attempts have been made to detect those at risk for SCD before athletic participation. However, its overall clinical advantages remain questionable in medical literature. This article will review cardiogenic and non-cardiogenic causes of SCD as well as discuss how this entity affects those athletes older than 35 years.

  13. Recovery of Idiopathic Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Edizer, Deniz Tuna; Çelebi, Özlem; Hamit, Bahtiyar; Baki, Ahmet; Yiğit, Özgür

    2015-08-01

    The objective was to identify and evaluate factors that may influence the recovery rate in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). A retrospective analysis was performed for patients with sudden sensorineural hearing loss between 2009 and 2013. Those with an identified etiology were excluded. The patients were divided into four treatment groups: (i) systemic corticosteroids (SC) only, (ii) SC+low-molecular-weight heparin (LMWH), (iii) SC+hyperbaric oxygen (HBO), and (iv) SC+LMWH+HBO. Recovery was evaluated according to Siegel's criteria. Age, initial hearing level, onset, treatment and audiogram types, comorbidities, and associated tinnitus and vestibular symptoms were investigated for their impact on prognosis. Two hundred five patients with ISSNHL were included. Recovery was seen in 59% of the patients. The complete recovery rate was significantly lower in patients older than 60 years and in patients presenting with profound hearing loss. Different audiogram curves had no significant effect on recovery. Sudden hearing loss was accompanied by tinnitus in 107 (52.1%) patients and vestibular symptoms in 55 (26.8%); however, neither was noted to affect prognosis. Different treatment combinations did not significantly affect prognosis. However, hypertension and a delay in treatment by more than 10 days from the onset of hearing loss were associated with a worse prognosis. Profound hearing loss, older than 60 years, a delay in treatment by more than 10 days, and hypertension were negative prognostic factors in this study, whereas, the type of audiogram curve and addition of HBO to SC did not affect prognosis.

  14. Sudden hearing loss associated with methylphenidate therapy.

    Science.gov (United States)

    Karapinar, Ugur; Saglam, Omer; Dursun, Engin; Cetin, Bilal; Salman, Nergis; Sahan, Murat

    2014-01-01

    An 8-year-old child diagnosed with attention deficit/hyperactivity disorder presented to our Department of Otolaryngology 4 days after suffering hearing loss, loss of balance, tinnitus, and fullness sensation of the left ear. Her symptoms occured with the first dose of methylphenidate. The medical history and physical examination revealed no other diseases associated with sudden hearing loss. The audiogram revealed a total hearing loss on the left ear. Stapedial reflexes, distortion product and transient-evoked otoacoustic emissions were absent in left ear. The absence of clinical, laboratory and radiological evidence of a possible cause for complaints, an association between methylphenidate and sudden hearing loss was suggested. The patient received a standard course of oral corticosteroid and hyperbaric oxygen therapy. Weekly otological and audiological examinations were performed. Conservative and medical treatments offered no relief from hearing loss. Sudden hearing loss is a serious and irreversible adverse effect of methylphenidate. Therefore, the risk of hearing loss should be taken into consideration when initiating methylphenidate therapy.

  15. Imaging spectrum of sudden athlete cardiac death.

    LENUS (Irish Health Repository)

    Arrigan, M T

    2012-02-01

    Sudden athlete death (SAD) is a widely publicized and increasingly reported phenomenon. For many, the athlete population epitomize human physical endeavour and achievement and their unexpected death comes with a significant emotional impact on the public. Sudden deaths within this group are often without prior warning. Preceding symptoms of exertional syncope and chest pain do, however, occur and warrant investigation. Similarly, a positive family history of sudden death in a young person or a known family history of a condition associated with SAD necessitates further tests. Screening programmes aimed at detecting those at risk individuals also exist with the aim of reducing fatalities. In this paper we review the topic of SAD and discuss the epidemiology, aetiology, and clinical presentations. We then proceed to discuss each underlying cause, in turn discussing the pathophysiology of each condition. This is followed by a discussion of useful imaging methods with an emphasis on cardiac magnetic resonance and cardiac computed tomography and how these address the various issues raised by the pathophysiology of each entity. We conclude by proposing imaging algorithms for the investigation of patients considered at risk for these conditions and discuss the various issues raised in screening.

  16. [Character of early tinnitus about sudden deafness].

    Science.gov (United States)

    Wang, Rongguo; Guo, Mingli; Miao, Yingzhang

    2015-05-01

    To study the clinical characteristics of early tinnitus in patients with sudden deafness. Forty-seven patients with sudden deafness and early tinnitus recieved subjective review and filled out classified questionnaire of tinnitus. By pure tone audiometry and tinnitus matching test, we obtain the distribution, quantity and matching loudness of tinnitus patients. (1) Objective examination: the most common frequencies of tinnitus were 8000 Hz and 4000 Hz. The most common numbers were two frequencies. The matching loudness was (16.63 ± 8.37) dB. (2) Subjective examination: the tinnitus was monotone (74.0%), sustained (89.0%), third level loudness (45.0%), third level annoying (60.0%), high frequency (83.0%), sound of cicadas (66.7%). The most influencing factors were hearing (28.2%) and mood (29.5%). (3) Relationship between tinnitus and pure tone hearing threshold curve: there was a significant correlation between the frequency of pure tone audiometry and the matching loudness of tinnitus (r = -0. 370, P 0.05). (1) The results of subjective examination were consistent with those of objective examination. (2) The tinnitus should be considered in the early treatment of sudden deafness.

  17. Sudden sensorineural hearing loss: an otologic emergency.

    Science.gov (United States)

    Vijayendra, H; Buggaveeti, Greeshma; Parikh, Bhavin; Sangitha, R

    2012-03-01

    The study purpose was to determine the efficacy of steroids, volume expanders and antivirals in the management of idiopathic sudden sensory neural hearing loss and to establish importance of early medical intervention. In this prospective study, thirty-four patients presenting with idiopathic sudden hearing loss of 30 db or more were enrolled in study group between 2005 and 2009. Patient variables as they related to recovery were studied and include patient age, time to onset of therapy, status of contralateral ear, presence of diabetes, severity of hearing loss, pattern of hearing loss in audiogram and presence of associated symptoms, (tinnitus, vertigo). Treatment protocol with intravenous hydrocortisone, intravenous dextran and oral anti-viral agent was followed. Pre-treatment and post-treatment pure tone average was analyzed. With combination therapy the overall improvement in pure tone threshold was seen in 27 patients (79.4%). A statistically significant association was found between the time at which medical intervention was started and hearing improvement. Early intervention in patients presenting before 3 days has given 77.8% complete type 1 recovery Idiopathic sudden sensory neural hearing loss is a medical emergency. It should not be misdiagnosed. Early detection and management with volume expanders, steroids and antivirals will improve the chances of complete recovery.

  18. The etiology of idiopathic sudden sensorineural hearing loss - Experimental herpes simplex virus infections of the inner ear

    NARCIS (Netherlands)

    Stokroos, RJ; Albers, FWJ; Schirm, J

    Hypothesis: Experimentally induced herpes simplex virus type 1 (HSV-1) labyrinthitis provides a suitable model for idiopathic sudden sensorineural hearing loss (ISSHL). Background: Viral labyrinthitis has been postulated to play a role in the pathophysiology of ISSHL. Circumstantial evidence is

  19. KRITERIA DIAGNOSIS DAN DIAGNOSIS BANDING SUDDEN DEAFNESS (SSNHL)

    OpenAIRE

    Arvindan Subramaniam

    2016-01-01

    Introduction: Sudden deafness or sudden sensorineural hearing loss (SSNHL) is defined as sensorineural hearing loss of more than 30 dB at three consecutive frequencies within 3 days of onset, often unilateral and idiopathic. Etiology of sudden deafness is still not known, but there are many theories put forward by the experts as a risk factor for sudden deafness. The prevalence of sudden deafness 5-30 per 100,000 people per year. Distribution of men and women almost equally, with the peak age...

  20. [Analysis of personality characteristics of sudden deafness patients].

    Science.gov (United States)

    An, Huiqin; Guo, Mingli; Han, Xiaoli; Bu, Guiqing

    2014-04-01

    To Study the personality characteristics in patients with sudden deafness. Thirty-eight sudden deafness patients and 45 healthy volunteers were assessed by Eysenck personality questionnaire (EPQ). The standard scores of P, E, N dimensions of patients with sudden deafness were greater than healthy volunteers. The standard score in L dimensions of patients with sudden deafness was less than healthy volunteers. The difference of the standard score of P dimension revealed statistical significance (P 0.05). Sudden deafness patients have emotional instability and psychoticism personality characteristics.

  1. KRITERIA DIAGNOSIS DAN DIAGNOSIS BANDING SUDDEN DEAFNESS (SSNHL)

    OpenAIRE

    Arvindan Subramaniam

    2016-01-01

    Introduction: Sudden deafness or sudden sensorineural hearing loss (SSNHL) is defined as sensorineural hearing loss of more than 30 dB at three consecutive frequencies within 3 days of onset, often unilateral and idiopathic. Etiology of sudden deafness is still not known, but there are many theories put forward by the experts as a risk factor for sudden deafness. The prevalence of sudden deafness 5-30 per 100,000 people per year. Distribution of men and women almost equally, with the peak age...

  2. Bidirectional infrasonic ducts associated with sudden stratospheric warming events

    Science.gov (United States)

    Assink, J. D.; Waxler, R.; Smets, P.; Evers, L. G.

    2014-02-01

    In January 2011, the state of the polar vortex in the midlatitudes changed significantly due to a minor sudden stratospheric warming event. As a result, a bidirectional duct for infrasound propagation developed in the middle atmosphere that persisted for 2 weeks. The ducts were due to two zonal wind jets, one between 30 and 50 km and the other around 70 km altitude. In this paper, using microbarom source modeling, a previously unidentified source region in the eastern Mediterranean is identified, besides the more well known microbarom source regions in the Atlantic Ocean. Infrasound data are then presented in which the above mentioned bidirectional duct is observed in microbarom signals recorded at the International Monitoring System station I48TN in Tunisia, from the Mediterranean region to the east and from the Atlantic Ocean to the west. While the frequency bands of the two sources overlap, the Mediterranean signal is coherent up to about 0.6 Hz. This observation is consistent with the microbarom source modeling; the discrepancy in the frequency band is related to differences in the ocean wave spectra for the two basins considered. This work demonstrates the sensitivity of infrasound to stratospheric dynamics and illustrates that the classic paradigm of a unidirectional stratospheric duct for infrasound propagation can be broken during a sudden stratospheric warming event.

  3. The Debate in Cuba's Scientific Community on Sudden Cardiac Death.

    Science.gov (United States)

    Vilches, Ernesto; Ochoa, Luis A; Ramos, Lianne

    2015-10-01

    Sudden cardiac death poses a challenge to modern medicine because of its high incidence, the unexpected and dramatic nature of the event, and years of potential life lost. What's more, despite modest decreases in global mortality attributed to cardiovascular diseases, incidence of sudden cardiac death has not declined. Cuba, like most of the Americas, suffers from knowledge gaps that hamper adequate strategies to address sudden cardiac death as a population health problem. We suggest that a generally accepted operational definition of sudden cardiac death be agreed upon, and a national registry developed that recognizes this cause of death on death certificates. These two actions will enable Cuba's public health authorities to assess the extent of the problem and to design intervention strategies for the population with intermediate and lower cardiovascular risk, the group in which most cases occur. KEYWORDS Sudden cardiac death, cardiovascular disease, sudden death, sudden cardiac arrest, risk reduction, prevention and control, Cuba.

  4. Experimental study of effectiveness of four radon mitigation solutions, based on underground depressurization, tested in prototype housing built in a high radon area in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Frutos Vazquez, Borja, E-mail: borjafv@ietcc.csic.e [Eduardo Torroja Institute for Construction Science (a Spanish National Research Council body), C/Serreno Galvache 4, 28033 Madrid (Spain); Olaya Adan, Manuel [Eduardo Torroja Institute for Construction Science (a Spanish National Research Council body), C/Serreno Galvache 4, 28033 Madrid (Spain); Santiago Quindos Poncela, Luis; Sainz Fernandez, Carlos; Fuente Merino, Ismael [Medical Physics, Chair of the Faculty of Medicine, University of Cantabria, Cardenal Herrera Oria s/n, 39011 Santander (Spain)

    2011-04-15

    The present paper discusses the results of an empirical study of four approaches to reducing indoor radon concentrations based on depressurization techniques in underground sumps. The experiments were conducted in prototype housing built in an area of Spain where the average radon concentration at a depth of 1 m is 250 kBq m{sup -3}. Sump effectiveness was analysed in two locations: underneath the basement, which involved cutting openings into the foundation, ground storey and roof slabs, and outside the basement walls, which entailed digging a pit alongside the building exterior. The effectiveness of both sumps was likewise tested with passive and forced ventilation methods. The systems proved to be highly efficient, lowering radon levels by 91-99%, except in the solution involving passive ventilation and the outside sump, where radon levels were reduced by 53-55%. At wind speeds of over 8 m/s, however, passive ventilation across an outside sump lowered radon levels by 95% due to a Venturi effect induced drop in pressure. - Highlights: {yields} This experience can help to delimit effectiveness of this kind of depressurization solutions because all of them has been tested in the same radon exhalation rate conditions and in the same building. In this sense this paper constitute an original work and even more if we note that initial radon concentration were very high, in order of 40 kBq m{sup -3} in the basement {yields} Radon reduction up to 300 Bq m{sup -3} from 40 kBq m{sup -3} (initial conditions inside the building) {yields} The systems proved to be highly efficient, reducing radon levels by 91-99%, with the exception of the outside sump-natural convection combination, where rates declined on the order of 53-55% {yields} The effectiveness of the sump located outside the basement walls rose by 40 percentage points (from 53 to 93%) when forced rather than passive extraction was used. {yields} The natural convection extraction systems proved to be 40% more

  5. GRB Afterglow Blast Wave Encountering Sudden Circumburst Density Change Produces No Flares

    CERN Document Server

    Gat, Ilana; MacFadyen, Andrew

    2013-01-01

    Afterglows of gamma-ray bursts are observed to produce light curves with the flux following power law evolution in time. However, recent observations reveal bright flares at times on the order of minutes to days. One proposed explanation for these flares is the interaction of a relativistic blast wave with a circumburst density transition. In this paper, we model this type of interaction computationally in one and two dimensions, using a relativistic hydrodynamics code with adaptive mesh refinement called ram, and analytically in one dimension. We simulate a blast wave traveling in a stellar wind environment that encounters a sudden change in density, followed by a homogeneous medium, and compute the observed radiation using a synchrotron model. We show that flares are not observable for an encounter with a sudden density increase, such as a wind termination shock, nor for an encounter with a sudden density decrease. Furthermore, by extending our analysis to two dimensions, we are able to resolve the spreadin...

  6. No flares from GRB afterglow blast waves encountering sudden circumburst density change

    CERN Document Server

    Gat, Ilana; MacFadyen, Andrew

    2013-01-01

    Afterglows of gamma-ray bursts are observed to produce light curves with the flux following power law evolution in time. However, recent observations reveal bright flares at times on the order of minutes to days. One proposed explanation for these flares is the interaction of a relativistic blast wave with a circumburst density transition. In this paper, we model this type of interaction computationally in one and two dimensions, using a relativistic hydrodynamics code with adaptive mesh refinement called RAM, and analytically in one dimension. We simulate a blast wave traveling in a stellar wind environment that encounters a sudden change in density, followed by a homogeneous medium, and compute the observed radiation using a synchrotron model. We show that flares are not observable for an encounter with a sudden density increase, such as a wind termination shock, nor for an encounter with a sudden density decrease. Furthermore, by extending our analysis to two dimensions, we are able to resolve the spreadin...

  7. A Case of Sudden Deafness with Intralabyrinthine Hemorrhage Intralabyrinthine Hemorrhage and Sudden Deafness.

    Science.gov (United States)

    Park, Jeong Jin; Jeong, Se Won; Lee, Jae Wook; Han, Su-Jin

    2015-12-01

    Sudden hearing deterioration may occur in our population, but it is difficult to explain the exact pathophysiology and the cause. Magnetic resonance imaging (MRI) in sudden sensorineural hearing loss (SSNHL) is usually useful to evaluate neural lesions such as acoustic schwannoma and hemorrhage in labyrinth. Recently some cases of SSNHL caused by intralabyrintine hemorrhage were reported by the advance of MRI. In the case of intralabyrintine hemorrhage, MRI showed a hyperintense signal in the labyrinth on the pre-contrast and contrast enhanced T1-weighted image and relatively weak intensity on T2-weighted image. The prognosis SSNHL by intralabyrintine hemorrhage is generally known to be poor. We report a case of sudden deafness with intralabyrintine hemorrhage who has a history of anticoagulant administration, with a review of literature.

  8. Potential Central Nervous System Involvement in Sudden Unexpected Infant Deaths and the Sudden Infant Death Syndrome.

    Science.gov (United States)

    Thach, Bradley T

    2015-07-01

    Sudden unexpected infant death (SUID) in infancy which includes Sudden Infant Death Syndrome (SIDS) is the commonest diagnosed cause of death in the United States for infants 1 month to 1 year of age. Central nervous system mechanisms likely contribute to many of these deaths. We discuss some of these including seizure disorders, prolonged breath holding, arousal from sleep and its habituation, laryngeal reflex apnea potentiated by upper airway infection, and failure of brainstem-mediated autoresuscitation. In the conclusions section, we speculate how lives saved through back sleeping might result in later developmental problems in certain infants who otherwise might have died while sleeping prone.

  9. 压力下降条件下一种双基发射药的瞬态燃烧特性%Transient Combustion Performance of Gun Propellant under Depressurization Condition

    Institute of Scientific and Technical Information of China (English)

    赵宏立; 刘来东; 靳建伟; 张衡; 赵宝明; 赵瑛; 张邹邹

    2012-01-01

    In order to study the transient combustion performance of the propellant under depressurization condition, the transient combustion behaviours of double-base gun propellant were studied by using a test equipment system under instantaneous depressurization. The results show that the instantaneous combustion of sample can be classified into two categories , e. g. extinguishment and burning-off, when the pressure of combustion chamber is controlled to vary from 0 to 151 Mpa,and the velocity of depressurization from 30 Mpa/s to 2. 5×104 Mpa/s. The extinguishment critical curve of sample combustion under the different initial pressure and depressurization velocity is unlike.%为了解火药在压力下降条件下的瞬态燃烧特性,采用压力瞬时下降状态下的实验装置系统,研究了一种双基发射药在瞬态降压下的燃烧行为.结果表明,在燃烧室压力为0~151 MPa,降压速率为(30~2.5×104) MPa/s条件下,该双基发射药的燃烧行为可分为熄灭和完全燃烧两种情况.在不同的初始压力和降压速率下,双基发射药有不同的熄火临界特性曲线.

  10. Sudden sensorineural hearing loss associated with vardenafil.

    Science.gov (United States)

    Snodgrass, Amanda J; Campbell, Heather M; Mace, David L; Faria, Victoria L; Swanson, Kathleen M; Holodniy, Mark

    2010-01-01

    The phosphodiesterase type 5 (PDE-5) inhibitors-sildenafil, vardenafil, and tadalafil-are used primarily in erectile dysfunction, but sildenafil is also indicated for pulmonary hypertension. Common adverse effects of vardenafil include headache, flushing, nasal congestion, dyspepsia, and nausea. Recently, PDE-5 inhibitors have been associated with adverse vision effects, and emerging evidence now indicates that they may also be responsible for hearing changes and hearing loss. We describe a patient who developed unilateral sudden sensorineural hearing loss possibly related to the use of vardenafil for erectile dysfunction. To our knowledge, only one other case of hearing loss related to this drug class has been published. Our patient was a 57-year-old man who came to the emergency department with right-sided mild-to-moderate hearing loss in the 500-3000-Hz range, confirmed by audiogram, that occurred after ingestion of vardenafil. The patient was hospitalized 2 days later for administration of intravenous dexamethasone, followed by oral prednisone. He reported that his hearing had improved on the fourth hospital day and was discharged 3 days later, continuing to taper the prednisone on an outpatient basis. A repeat audiogram after 10 days of corticosteroid therapy confirmed that his hearing in the 500-3000-Hz range was within normal limits. Use of the Naranjo adverse drug reaction probability scale indicated a possible (score of 3) adverse reaction of sudden sensorineural hearing loss associated with vardenafil consumption. We also performed an analysis of hearing loss cases related to PDE-5 inhibitors in the United States Food and Drug Administration's Adverse Event Reporting System database to compare the characteristics of our patient with those of other reported adverse event cases. Based on the temporal relation of the sudden sensorineural hearing loss to this patient's drug consumption, we propose that the vardenafil is a likely cause of the hearing loss

  11. Infectious causes of sudden infant death syndrome.

    Science.gov (United States)

    Alfelali, Mohammad; Khandaker, Gulam

    2014-12-01

    Investigators have long suspected the role of infection in sudden infant death syndrome (SIDS). Evidence of infectious associations with SIDS is accentuated through the presence of markers of infection and inflammation on autopsy of SIDS infants and isolates of some bacteria and viruses. Several observational studies have looked into the relation between seasonality and incidence of SIDS, which often showed a winter peak. These all may suggest an infectious aetiology of SIDS. In this review we have summarised the current literature on infectious aetiologies of SIDS by looking at viral, bacterial, genetic and environmental factors which are believed to be associated with SIDS.

  12. Sudden Sensorineural Hearing Loss: Primary Care Update.

    Science.gov (United States)

    Leung, Marcia A; Flaherty, Anna; Zhang, Julia A; Hara, Jared; Barber, Wayne; Burgess, Lawrence

    2016-06-01

    The primary care physician's role in recognizing sudden sensorineural hearing (SSNHL) loss and delivering initial treatment is critical in the management of the syndrome. This role involves recognizing its clinical symptoms, distinguishing it from conductive hearing loss with the Weber tuning fork or the Rauch hum test, and urgent administration of high dose oral corticosteroids. Diagnosis and treatment should not be delayed for audiometric testing or referral to otolaryngology. This paper provides an update on the initial evaluation and treatment of this syndrome based on the literature and clinical guideline recommendations.

  13. Cardiac channelopathies and sudden infant death syndrome

    DEFF Research Database (Denmark)

    Tfelt-Hansen, Jacob; Winkel, Bo Gregers; Grunnet, Morten

    2011-01-01

    Sudden infant death syndrome (SIDS) is always a devastating and unexpected occurrence. SIDS is the leading cause of death in the first 6 months after birth in the industrialized world. Since the discovery in 1998 of long QT syndrome as an underlying substrate for SIDS, around 10-20% of SIDS cases...... ion channel ß-subunits, and 3 genes encode other channel-interacting proteins. All 10 genes have been associated with primary electrical heart diseases. SIDS may hereby be the initial symptom of rare primary electric channelopathies such as long QT, short QT and Brugada syndrome, as well...

  14. Simultaneous occurrence of two independent vagal reflexes: a possible cause of vagal sudden death.

    Science.gov (United States)

    Alboni, Paolo; Alboni, Marco; Gianfranchi, Lorella

    2011-04-01

    A vagal origin of sudden death has been hypothesised in humans, but it has not yet been clearly demonstrated. Two vagal reflexes have been widely investigated: the diving reflex and the fear-induced central reaction, which are responsible for diving bradycardia and alarm bradycardia, respectively. The latter occurs in humans mainly in the context of emotional presyncope/syncope. A simultaneous occurrence of these two vagal reflexes has been observed in animals that are threatened while diving, and heart rates (HR) as low as two to six beats/min have been reported. In experiments carried out in rats, a high percentage of animals that were stressed before immersion in water died suddenly due to progressive slowing of HR; autopsy revealed no signs of drowning. No animals died if they had not been previously stressed. These data show that vagal sudden death can occur when the vagal cardiac fibres are synergically stimulated by two independent reflexes. In humans, it has been reported that in 10-15% of people who die after falling into water, autopsy reveals little or no water in the lungs. These sudden deaths could be due to vagal overactivity. The development of an adequate laboratory model may improve knowledge of the pathophysiology of this type of vagal sudden death and of its prevention.

  15. Desalination of oil sands process-affected water and basal depressurization water in Fort McMurray, Alberta, Canada: application of electrodialysis.

    Science.gov (United States)

    Kim, Eun-Sik; Dong, Shimiao; Liu, Yang; Gamal El-Din, Mohamed

    2013-01-01

    The high content of inorganic species in water used to extract bitumen from the Alberta oil sands and in the groundwater below the oil sands is an increasing environmental concern. These water matrices require treatment before they can be reused or safely discharged. Desalination of the oil sands process-affected water (OSPW) and groundwater, or basal depressurization water (BDW), can be accomplished with deionization techniques such as electrodialysis (ED). In order to achieve the effective ED treatment, OSPW and BDW were pretreated with coagulation-flocculation-sedimentation to remove solid species and turbidity. We demonstrated that a conductivity range for industrial reuse of OSPW and BDW can be achieved with the ED treatment and showed the possibility of applying ED in the oil sands industry. A continuous ED system that reuses the diluate stream as a source for the concentrate stream was designed. The cost of a hypothetical ED water treatment plant in Fort McMurray, Alberta, was estimated to be C$10.71 per cubic meter of treated water.

  16. ROSA/LSTF Tests and RELAP5 Posttest Analyses for PWR Safety System Using Steam Generator Secondary-Side Depressurization against Effects of Release of Nitrogen Gas Dissolved in Accumulator Water

    Directory of Open Access Journals (Sweden)

    Takeshi Takeda

    2016-01-01

    Full Text Available Two tests related to a new safety system for a pressurized water reactor were performed with the ROSA/LSTF (rig of safety assessment/large scale test facility. The tests simulated cold leg small-break loss-of-coolant accidents with 2-inch diameter break using an early steam generator (SG secondary-side depressurization with or without release of nitrogen gas dissolved in accumulator (ACC water. The SG depressurization was initiated by fully opening the depressurization valves in both SGs immediately after a safety injection signal. The pressure difference between the primary and SG secondary sides after the actuation of ACC system was larger in the test with the dissolved gas release than that in the test without the dissolved gas release. No core uncovery and heatup took place because of the ACC coolant injection and two-phase natural circulation. Long-term core cooling was ensured by the actuation of low-pressure injection system. The RELAP5 code predicted most of the overall trends of the major thermal-hydraulic responses after adjusting a break discharge coefficient for two-phase discharge flow under the assumption of releasing all the dissolved gas at the vessel upper plenum.

  17. How far is it to a sudden future singularity of pressure?

    CERN Document Server

    Dabrowski, Mariusz P; Hendry, Martin A

    2007-01-01

    We discuss the constraints coming from current observations of type Ia supernovae on cosmological models which allow sudden future singularities of pressure (with the scale factor and the energy density regular). We show that such a sudden singularity may happen in the very near future (e.g. within ten million years) and its prediction at the present moment of cosmic evolution cannot be distinguished, with current observational data, from the prediction given by the standard quintessence scenario of future evolution. Fortunately, sudden future singularities are characterized by a momentary peak of infinite tidal forces only; there is no geodesic incompletness which means that the evolution of the universe may eventually be continued throughout until another ``more serious'' singularity such as Big-Crunch or Big-Rip.

  18. How far is it to a sudden future singularity of pressure?

    Science.gov (United States)

    Dąbrowski, Mariusz P.; Denkiewicz, Tomasz; Hendry, Martin A.

    2007-06-01

    We discuss the constraints coming from current observations of type Ia supernovae on cosmological models which allow sudden future singularities of pressure (with the scale factor and the energy density regular). We show that such a sudden singularity may happen in the very near future (e.g. within 10×106years) and its prediction at the present moment of cosmic evolution cannot be distinguished, with current observational data, from the prediction given by the standard quintessence scenario of future evolution. Fortunately, sudden future singularities are characterized by a momentary peak of infinite tidal forces only; there is no geodesic incompleteness, which means that the evolution of the universe may eventually be continued throughout until another “more serious” singularity such as a big crunch or big rip.

  19. Controllable entanglement sudden birth of Heisenberg spins%Controllable entanglement sudden birth of Heisenberg spins

    Institute of Scientific and Technical Information of China (English)

    ZHENG Qiang; ZHI Qi-Jun; ZHANG Xiao-Ping; REN Zhong-Zhou

    2011-01-01

    We investigate the Entanglement Sudden Birth (ESB) of two Heisenberg spins A and B. The third controller, qutrit C is introduced, which only has the Dzyaloshinskii-Moriya (DM) spin-orbit interaction with qubit B. We find that the DM interaction is necessa

  20. Studying VEMP in Sudden Sensorineural Hearing Loss

    Directory of Open Access Journals (Sweden)

    Mohsen Rajati

    2011-03-01

    Full Text Available Introduction: Sudden sensorineural hearing loss (SSNHL has a prevalence of 10 in 100,000. Viral infections, vascular obstruction and rupture of the intracochlear membranes are supposed to be its most common etiologies. About 40% of patients experience vertigo or imbalance. The VEMP (vestibular evoked myogenic potentials test is a known approach for detailed study of the labyrinth. The advantage of this test in comparison to other tests is the selected study of sacculus and sacculocochlear pathways. Materials and Methods:  In this cross sectional study all patients with SSNHL diagnosis were admitted and underwent routine standard treatments and diagnostic tests. Clinical symptoms and paraclinic findings were recorded in especially designed forms and VEMP test was performed on admission. Results: Among the 43 cases with sudden sensorineural hearing loss, 14 (32.6% had vertigo. Thirteen patients (39.2% out of 43 had a negative (abnormal VEMP, 6 of which (42.9% had vertigo, while in the 30 VEMP positive (normal cases, vertigo was detected in 8 (26.6%. Discussion: Saccular dysfunction seems to be an important finding in SSNHL. Although it is more prevalent in the patients with vertigo, it can be found in the non-dizzy cases. VEMP disturbance in SSNHL shows more extensive pathological involvement. Conclusion: In SSNHL the pathology isn’t limited to the cochlea and even in patients with no vestibular symptoms sacculus might be involved.

  1. Is Sudden Hearing Loss Associated with Atherosclerosis?

    Directory of Open Access Journals (Sweden)

    Mohsen Rajati

    2016-05-01

    Full Text Available Introduction: Sudden sensorineural hearing-loss (SSNHL patients constitute approximately 2–3% of referrals to ear, nose and throat (ENT clinics. Several predisposing factors have been proposed for this condition; one of which is vascular disorders and perfusion compromise. In this research the atherosclerotic changes and their known risk factors are studied in SSNHL patients.   Materials and Methods: Thirty SSNHL patients and 30 controls were evaluated with regard to cardiovascular risks including history, heart examination, blood pressure, body mass index, waist circumference, electrocardiogram, blood sugar, triglycerides, cholesterol, high-sensitivity C-reactive protein (HSCRP; also, carotid artery color Doppler study was undertaken to measure intima media thickness(IMT.   Results: IMT and HSCRP showed an increased risk in the case group compared with the controls (P= 0.005 & P=0.001. However, waist circumference, history of smoking, fasting blood sugar, lipid profile, and electrocardiogram revealed no significant difference between the two groups. Interestingly, blood pressure and body mass index were higher in the controls in this study.   Conclusion:  Sudden sensorineural hearing loss may be associated with subclinical atherosclerosis.

  2. Scleroderma and sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Ravinder Verma

    2014-01-01

    Full Text Available Sudden sensorineural hearing loss (SNHL is an emergency in otolaryngological practice. The exact cause, in most of the cases cannot be found. A triad of vascular, viral, and membrane rupture are the known theories for the causation of sudden SNHL. Now various autoimmune disorders have also been suggested to play a role in the pathogenesis. Autoimmune inner ear disease in human being is an uncommon, but a distinct clinical entity. The diagnosis of the inner ear autoimmune disorder depends mainly on relatively distinct clinical course, immune laboratory tests and treatment response. The clinical picture usually consists of bilateral SNHL, bilateral reduced vestibular loss and symptoms of pressure with tinnitus and rarely tissue destruction of middle and external ear. Systemic scleroderma is an aggressive multi-system and multistage connective tissue disorder with high mortality. It is characterized by proliferative vascular lesion and marked deposition of collagen in various tissues and organs. Responses to immunosuppressive drugs are cited as evidence of an autoimmune process.

  3. Is Sudden Hearing Loss Associated with Atherosclerosis?

    Science.gov (United States)

    Rajati, Mohsen; Azarpajooh, Mahmoud Reza; Mouhebati, Mohsen; Nasrollahi, Mostafa; Salehi, Maryam; Khadivi, Ehsan; Nourizadeh, Navid; Hashemi, Firoozeh; Bakhshaee, Mehdi

    2016-01-01

    Introduction: Sudden sensorineural hearing-loss (SSNHL) patients constitute approximately 2–3% of referrals to ear, nose and throat (ENT) clinics. Several predisposing factors have been proposed for this condition; one of which is vascular disorders and perfusion compromise. In this research the atherosclerotic changes and their known risk factors are studied in SSNHL patients. Materials and Methods: Thirty SSNHL patients and 30 controls were evaluated with regard to cardiovascular risks including history, heart examination, blood pressure, body mass index, waist circumference, electrocardiogram, blood sugar, triglycerides, cholesterol, high-sensitivity C-reactive protein (HSCRP); also, carotid artery color Doppler study was undertaken to measure intima media thickness(IMT). Results: IMT and HSCRP showed an increased risk in the case group compared with the controls (P= 0.005 & P=0.001). However, waist circumference, history of smoking, fasting blood sugar, lipid profile, and electrocardiogram revealed no significant difference between the two groups. Interestingly, blood pressure and body mass index were higher in the controls in this study. Conclusion: Sudden sensorineural hearing loss may be associated with subclinical atherosclerosis. PMID:27429947

  4. [Sudden deafness as a presentation of acoustic neuroma].

    Science.gov (United States)

    Bartoszewicz, Robert; Niemczyk, Kazimierz; Marchel, Andrzej; Kowalska, Małgorzata

    2005-09-01

    Sudden deafness (SD) is thought to be a heterogenic group of disorders as to etiopathogenesis. Acoustic neuroma should always be considered in the differential diagnosis. The authors analysed symptoms occurring in the group of 89 patients, diagnosed with acoustic neuroma. A special attention was paid to the role of sudden deafness as a clinical manifestation of the VIIIth nerve pathology. Progressive hearing loss, tinnitus, headache and sudden deafness were the most common complaints. Sudden deafness was developed by approximately 1 of the investigated patients (24.7%). Progressive hearing loss, tinnitus and sudden deafness were also dominating initial signs. The sudden deafness onset was preceded by the period of progressive hearing loss in 3 patients. In one case episode of SD occurred twice.

  5. Sudden deafness and right-to-left shunts.

    Science.gov (United States)

    Iguchi, Yasuyuki; Kimura, Kazumi; Kobayashi, Kazuto; Tachi, Toshihiro; Aihara, Teruhito; Harada, Tamotsu

    2008-01-01

    One of the etiologies for idiopathic sudden deafness is considered to be ischemia of the inner ear. Cryptogenic stroke is caused by a right-to-left shunt (RLS). The present study investigated whether RLS is associated with the occurrence of sudden deafness. Contrast saline transcranial Doppler ultrasonography was performed to detect RLS. Subjects comprised 23 consecutive sudden deafness patients and 46 age- and gender-matched controls. Clinical characteristics, including vascular risk factors, were compared between sudden deafness and control groups. RLS was more frequent in the sudden deafness group than in controls (48 vs. 17%, p = 0.011). No significant differences in other clinical characteristics were seen between groups. RLS may be a potential cause of sudden deafness. Copyright 2008 S. Karger AG, Basel.

  6. Macrocytosis and sudden sensorineural hearing loss: a case report.

    Science.gov (United States)

    McMurran, A E L; Adair, R A

    2015-11-01

    Although other blood dyscrasias are known to cause sudden sensorineural hearing loss, macrocytosis has not previously been implicated in the absence of another causative agent. We present a case of bilateral sequential sudden sensorineural hearing loss in a patient with significant macrocytosis (mean corpuscular volume at presentation 124 fl) secondary to alcohol-induced liver dysfunction. A possible pathophysiological mechanism linking macrocytosis and sudden sensorineural hearing loss was identified, suggesting areas for further investigation.

  7. Pathophysiology of reversible sudden deafness--epidemiological study.

    OpenAIRE

    Ohsaki, Katsuichiro; Aoyama, Hideyasu

    1983-01-01

    Many aspects of the etiology and pathophysiology of reversible sudden deafness remain obscure. In order to better understand the pathophysiology of reversible sudden deafness we compared the results of two therapies which have different mechanisms of action. The results of therapy with tranexamic acid alone in 49 cases (57 ears) of sudden deafness were compared with the results of treatment with so-called antisludging agents in 65 cases (69 ears) using the chi square contingency test. The sam...

  8. Pathophysiology of reversible sudden deafness--epidemiological study.

    OpenAIRE

    Ohsaki, Katsuichiro; Aoyama, Hideyasu

    1983-01-01

    Many aspects of the etiology and pathophysiology of reversible sudden deafness remain obscure. In order to better understand the pathophysiology of reversible sudden deafness we compared the results of two therapies which have different mechanisms of action. The results of therapy with tranexamic acid alone in 49 cases (57 ears) of sudden deafness were compared with the results of treatment with so-called antisludging agents in 65 cases (69 ears) using the chi square contingency test. The sam...

  9. Mapping the risk of sudden oak death in Oregon: prioritizing locations for early detection and eradication

    Science.gov (United States)

    V& aacute; clavík Tom& aacute; & scaron; Alan Kanaskie; Ellen Goheen; Janet Ohmann; Everett Hansen; Ross Meentemeyer

    2010-01-01

    Phytophthora ramorum was first discovered in forests of southwestern Oregon in 2001. Despite intense eradication efforts, disease continues to spread from initially infested sites because of the late discovery of disease outbreaks and incomplete detection. Here we present two GIS predictive models of sudden oak death (SOD) establishment and spread...

  10. Hyperbaric oxygen therapy for sudden sensorineural hearing loss in divers.

    Science.gov (United States)

    Van Der Wal, A W; Van Ooij, P J A M; De Ru, J A

    2016-11-01

    Sudden sensorineural hearing loss in divers may be caused by either inner-ear barotrauma or inner-ear decompression sickness. There is no consensus on the best treatment option. This study aimed to evaluate the therapeutic value of hyperbaric oxygen therapy for sudden sensorineural hearing loss in divers. A literature review and three cases of divers with sudden sensorineural hearing loss treated with hyperbaric oxygen therapy are presented. Hyperbaric oxygen therapy resulted in hearing improvement in 80 per cent of patients: 39 per cent had hearing improvement and 41 per cent had full recovery. Hyperbaric oxygen therapy improved hearing in divers with sudden sensorineural hearing loss.

  11. KRITERIA DIAGNOSIS DAN DIAGNOSIS BANDING SUDDEN DEAFNESS (SSNHL

    Directory of Open Access Journals (Sweden)

    Arvindan Subramaniam

    2016-03-01

    Full Text Available Introduction: Sudden deafness or sudden sensorineural hearing loss (SSNHL is defined as sensorineural hearing loss of more than 30 dB at three consecutive frequencies within 3 days of onset, often unilateral and idiopathic. Etiology of sudden deafness is still not known, but there are many theories put forward by the experts as a risk factor for sudden deafness. The prevalence of sudden deafness 5-30 per 100,000 people per year. Distribution of men and women almost equally, with the peak age of 50-60 years. Sudden deafness diagnosis is made based on history, physical examination and audiometry. Sudden deafness has three characteristics; acute, sensorineural hearing loss and unknown etiology. Additional characteristics may include vertigo, tinnitus and the absence of cranial nerve involvement. Management of sudden deafness include conservative therapy with multiple modalities. Case: Patient male, 40 years, Bali, Hindu present with hearing loss since ± 2 weeks ago. Patients previously complained of heat in the ear ± 2 days ago accompanied by a downward hearing and ears. A history of vomiting, coughs and colds denied. History of treatment at the hospital and was hospitalized for ± 2 weeks. Patients had never suffered from the same disease. No history of sinusitis, allergy, anemia, autoimmune and other systemic diseases. Patients also had never experienced trauma and underwent nasal surgery before. Keywords:sudden deafness, sensorineural, audiometry.

  12. Sudden cardiac death in adults: causes, incidence and interventions.

    Science.gov (United States)

    Walker, Wendy Marina

    Many nurses will be familiar with the unexpected death of an adult patient following a sudden, life-threatening cardiac event. It is a situation that demands sensitive nursing care and skilled interventions to provide a foundation for recovery and promote healthy bereavement. This article examines the causes and incidence of sudden cardiac death in adults. Possible reactions of those who are suddenly bereaved are described and immediate care interventions aimed at dealing with the grief process are discussed. The article concludes by identifying ways in which the incidence of sudden cardiac death may be reduced.

  13. Sudden cardiac death in young athletes

    Directory of Open Access Journals (Sweden)

    Östman-Smith I

    2011-07-01

    Full Text Available Ingegerd Östman-SmithDivision of Paediatric Cardiology, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, SwedenAbstract: Athletic activity is associated with an increased risk of sudden death for individuals with some congenital or acquired heart disorders. This review considers in particular the causes of death affecting athletes below 35 years of age. In this age group the largest proportion of deaths are caused by diseases with autosomal dominant inheritance such as hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, long QT-syndrome, and Marfan’s syndrome. A policy of early cascade-screening of all first-degree relatives of patients with these disorders will therefore detect a substantial number of individuals at risk. A strictly regulated system with preparticipation screening of all athletes following a protocol pioneered in Italy, including school-age children, can also detect cases caused by sporadic new mutations and has been shown to reduce excess mortality among athletes substantially. Recommendations for screening procedure are reviewed. It is concluded that ECG screening ought to be part of preparticipation screening, but using criteria that do not cause too many false positives among athletes. One such suggested protocol will show positive in approximately 5% of screened individuals, among whom many will be screened for these diseases. On this point further research is needed to define what kind of false-positive and false-negative rate these new criteria result in. A less formal system based on cascade-screening of relatives, education of coaches about suspicious symptoms, and preparticipation questionnaires used by athletic clubs, has been associated over time with a sizeable reduction in sudden cardiac deaths among Swedish athletes, and thus appears to be worth implementing even for junior athletes not recommended for formal preparticipation screening. It is strongly argued

  14. Sudden hearing loss: National survey in Spain.

    Science.gov (United States)

    Amarillo, Elizabeth; Hernández-García, Estefanía; Herrera, Mayte; García Berrocal, José Ramón; García Arumí, Ana; Durio, Enrique; Plaza, Guillermo

    2016-01-01

    The objective of our study was to identify the diagnostic and therapeutic approaches in the different ENT Departments of Spain with respect to sudden deafness. We wanted to establish a basis to help to create a new nation-wide consensus, unifying treatment, diagnostic and follow-up criteria for this disease. We carried out an anonymous Internet survey, addressing Spanish ENT doctors nation-wide (n=2,029), gathering in 33 questions different aspects about diagnostic criteria, additional tests, treatment procedures and prognostic factors in sudden deafness, according to the different protocols and experience of the participants in the survey. A total of 293 Spanish ENT doctors (14%) took part anonymously. In relation to diagnostic criteria, is the most noteworthy was the requisite of a confirmed neurosensorial loss (91.1%) followed by "initiated in less than three days" (75%) and 3 consecutive frequencies affected (76.4%). More than half of the participants requested an MRI of the IAC/CPA (68.7%) and 88.2% used gadolinium in this test. The prognostic factor most frequently considered was delay in commencement of treatment onset (84.8%). As far as treatment of primary cases, most of the responders agreed on the use of corticosteroids (99.7%). Oral administration was the most widely used (66%), followed by intravenous (29.6%) and intratympanic (1.4%) administration. Ninety-two percent had not had any major complications with systemic steroids. Intratympanic treatments were used by 70% of responders for rescue in failure. In Spain there is currently a significant disparity of concepts regarding the diagnosis of sudden deafness, and more agreement as to using steroids as their treatment. This highlights the need to implement measures to promote a better approach, which would be homogeneous and consensual, to this condition. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  15. Sudden losses and sudden gains during a DBT-PTSD treatment for posttraumatic stress disorder following childhood sexual abuse

    Directory of Open Access Journals (Sweden)

    Antje Krüger

    2014-09-01

    Full Text Available Background: Exposure-based treatment approaches are first-line interventions for patients suffering from posttraumatic stress disorder (PTSD. However, the dissemination of exposure-based treatments for PTSD is challenging, as a large proportion of clinicians report being concerned about symptoms worsening as a result of this type of intervention and are therefore reluctant to offer it to patients with PTSD. However, there is only little empirical evidence to date on the pattern of symptom worsening during exposure-based treatment for PTSD. Objective: The goal of the present study was to explore the frequency of sudden losses and sudden gains in the course of an exposure-based treatment programme for female patients suffering from PTSD related to childhood sexual abuse who also show severe comorbidity. In addition, the relationship between sudden changes and treatment outcome was examined. Methods: Female participants (N=74 were randomised to either a 12-week residential DBT-PTSD programme or a treatment-as-usual wait list. The pattern of symptom change was assessed via weekly assessments using the Posttraumatic Diagnostic Scale (PDS. Sudden changes were computed as suggested by the literature on sudden gains. Results: During treatment, only one participant (3% experienced a sudden loss, whereas 25% of participants experienced sudden gains. In the waiting condition, 8% of the participants experienced sudden losses and 5% experienced sudden gains during the same time period. No symptom worsening was observed in response to exposure sessions. However, sudden gains occurred during exposure and non-exposure treatment weeks. Patients with sudden gains showed better treatment outcome in the post-treatment and follow-up assessments. Conclusions: Exposure-based treatment did not lead to PTSD symptom worsening in the study sample. Results show that sudden gains occur frequently during PTSD treatment and have a prognostic value for treatment outcome.

  16. Diuretic Agents in Treatment of Sudden Deafness

    Institute of Scientific and Technical Information of China (English)

    JI Chang-you; LI Hong-tao; ZHOU Ding-rong; CHEN Ji-chuan; WANG Yi-nan; GUAN Li-qian; ZHANG Min

    2008-01-01

    Objective To study the role of diuretic agents in treating sudden deafness (SD) and explore the possibility of endolymphatic hydrops as a potential cause of SD. Methods Twenty-eight SD cases were reviewed. In 23 cases, treatment was initiated with routine agents. Diuretic agents were later added in 8 of these cases that failed to respond to routine treatment agents. Diuretic agents were included in the initial treatment in the rest 5 cases. In total, 13 cases received diuretics in addition to routine treatment agents and 15 cases received conventional treatment only. Results In the 8 cases who received diuretics after failed conventional treatments, 4 showed hearing improvement, whereas all 5 cases in which diuretics were included in the initial treatment demonstrated hearing improvement. Conclusion These results suggest a possible role of endolymphatic hydrops in the pathophysiologic course of SD. Diuretics should be considered when clear indications exist with no conflicts to other medical conditions.

  17. Diclofenac induced sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    M Bhanukumar

    2015-07-01

    Full Text Available A few cases of mild to moderate, gradual and reversible sensorineural hearing loss (SNHL with prolonged doses of nonsteroidal anti-inflammatory drugs has been reported. We present a case of sudden irreversible SNHL in a 60-year-old female after taking a single dose of diclofenac. The patient was a known case of diabetes mellitus and hypertension and was on regular treatment. We postulate that the patient's hearing loss was the result of diclofenac's ototoxic effects which may have been potentiated as a result of her long standing diabetes, hypertension and old age. Accordingly, we recommend the cautious use of diclofenac in patients with underlying diseases where diclofenac induced ototoxicity could potentially result in adverse otologic consequences.

  18. Assigning cause for sudden unexpected infant death.

    Science.gov (United States)

    Hunt, Carl E; Darnall, Robert A; McEntire, Betty L; Hyma, Bruce A

    2015-06-01

    We have reached a conundrum in assigning cause of death for sudden unexpected infant deaths. We summarize the discordant perspectives and approaches and how they have occurred, and recommend a pathway toward improved consistency. This lack of consistency affects pediatricians and other health care professionals, scientific investigators, medical examiners and coroners, law enforcement agencies, families, and support or advocacy groups. We recommend that an interdisciplinary international committee be organized to review current approaches for assigning cause of death, and to identify a consensus strategy for improving consistency. This effort will need to encompass intrinsic risk factors or infant vulnerability in addition to known environmental risk factors including unsafe sleep settings, and must be sufficiently flexible to accommodate a progressively expanding knowledge base.

  19. Sudden hearing loss after dental treatment.

    Science.gov (United States)

    Kansu, Leyla; Yilmaz, Ismail

    2013-08-01

    A 66-year-old man presented with impaired balance, tinnitus, sensation of blockage, and hearing loss in his left ear, which developed after dental treatment for dental pain 4 days previously. Treatment of the carious left upper second molar tooth had included pulp extirpation, canal expansion, and tooth filling under local anesthesia with articaine and epinephrine. Impaired balance decreased spontaneously within 3 days of dental treatment, but tinnitus and hearing loss persisted. Pure tone audiogram showed profound sensorineural hearing loss in the left ear, with a downslope from 40 to 100 dB, and an abnormal speech discrimination score (50%). Treatment included intravenous prednisolone, intratympanic dexamethasone, and oral betahistine and trimetazidine. The patient had improved hearing and resolution of tinnitus. Sudden hearing loss is rare after dental treatment, and awareness of this complication may prompt early referral for treatment and may improve recovery and prognosis. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. All rights reserved.

  20. Symptoms Before Sudden Arrhythmic Death Syndrome

    DEFF Research Database (Denmark)

    Glinge, Charlotte; Jabbari, Reza; Risgaard, Bjarke

    2015-01-01

    INTRODUCTION: No studies in an unselected and nationwide setting have characterized the symptoms and medical history of patients with sudden arrhythmic death syndrome (SADS). The aim of this study was to identify and describe the symptoms and medical history of patients before the presentation....... The National Patient Registry was utilized to obtain information on all in- and outpatient activity in Danish hospitals. All medical records from hospitals and general practitioners, including death certificates and autopsy reports were reviewed. Before death, 48 (35%) SADS patients had cardiac symptoms; among...... these, 30 (22%) had contacted the healthcare system. Antecedent symptoms (symptoms >24 hours before death) were present in 34 (25%) patients. Prodromal symptoms (symptoms ≤24 hours before death) were present in 23 (17%) patients. Cardiac symptoms included chest pain (n = 16, 12%), dyspnea (n = 18, 13...

  1. Systems-level perspective of sudden infant death syndrome.

    Science.gov (United States)

    Salomonis, Nathan

    2014-09-01

    Sudden infant death syndrome (SIDS) remains one of the primary causes of infant mortality in developed countries. Although the causes of SIDS remain largely inconclusive, some of the most informative associations implicate molecular, genetic, anatomical, physiological, and environmental (i.e., infant sleep) factors. Thus, a comprehensive and evolving systems-level model is required to understand SIDS susceptibility. Such models, by being powerful enough to uncover indirect associations, could be used to expand our list of candidate targets for in-depth analysis. We present an integrated WikiPathways model for SIDS susceptibility that includes associated cell systems, signaling pathways, genetics, and animal phenotypes. Experimental and literature-based gene-regulatory data have been integrated into this model to identify intersecting upstream control elements and associated interactions. To expand this pathway model, we performed a comprehensive analysis of existing proteomics data from brainstem samples of infants with SIDS. From this analysis, we discovered changes in the expression of several proteins linked to known SIDS pathologies, including factors involved in glial cell production, hypoxia regulation, and synaptic vesicle release, in addition to interactions with annotated SIDS markers. Our results highlight new targets for further consideration that further enrich this pathway model, which, over time, can improve as a wiki-based, community curation project.

  2. Risk factors and causes of sudden noncardiac death

    DEFF Research Database (Denmark)

    Risgaard, Bjarke; Lynge, Thomas Hadberg; Wissenberg, Mads

    2015-01-01

    BACKGROUND: On the performance of an autopsy, sudden deaths may be divided into 2 classifications: (1) sudden cardiac deaths and (2) sudden noncardiac deaths (SNCDs). Families of SNCD victims should not be followed up as a means of searching for cardiac disease. OBJECTIVE: The purpose of this stu...... of cardiac comorbidities. These data may guide future strategies for the follow-up of family members of nonautopsied sudden death victims, improve risk stratification, and influence public health strategies.......BACKGROUND: On the performance of an autopsy, sudden deaths may be divided into 2 classifications: (1) sudden cardiac deaths and (2) sudden noncardiac deaths (SNCDs). Families of SNCD victims should not be followed up as a means of searching for cardiac disease. OBJECTIVE: The purpose of this study...... was to report the risk factors and causes of SNCD. METHODS: We conducted a retrospective, nationwide study including all deaths between 2000 and 2006 of individuals aged 1-35 years and all deaths between 2007 and 2009 of individuals aged 1-49 years. Two physicians identified all sudden death cases through...

  3. New Areas for Preventive Programing: Sudden Infant Death Syndrome.

    Science.gov (United States)

    Lowman, Joseph

    Crisis intervention programs for persons experiencing the sudden death of family members or surviving natural disasters have been advocated as methods of primary prevention, although few have actually been implemented. A program utilizing nurses to deliver grief intervention to parents losing a baby to Sudden Infant Death Syndrome (SIDS) was…

  4. Sudden cardiac death and mitral and aortic valve disease

    Directory of Open Access Journals (Sweden)

    Bockeria O.L.

    2013-09-01

    Independent determinants of sudden death were left ventricular ejection fraction and atrial fibrillation. The main cause of death in patients with mitral valve stenosis is a thromboembolism from the left heart chambers to systemic circulation, and the risk of the latter increases with atrial fibrillation. There is no sudden cardiac death in mitral valve stenosis. The absence of left ventricular remodeling in mitral valve stenosis probably explains this finding. Onset of symptoms and signs of left ventricular dysfunction are the main predictors of sudden death and are indications for surgery. It should be emphasized that the database of sudden cardiac death in patients with valvular heart disease is very limited compared to patients with coronary heart disease and cardiomyopathies. Some issues related to predictors and mechanisms of SCD are currently poorly understood, therefore prevention of sudden cardiac death is difficult, especially in asymptomatic patients.

  5. Sudden cardiac arrest in people with epilepsy in the community

    Science.gov (United States)

    Lamberts, Robert J.; Blom, Marieke T.; Wassenaar, Merel; Bardai, Abdennasser; Leijten, Frans S.; de Haan, Gerrit-Jan; Sander, Josemir W.; Thijs, Roland D.

    2015-01-01

    Objective: To ascertain whether characteristics of ventricular tachycardia/fibrillation (VT/VF) differed between people with epilepsy and those without and which individuals with epilepsy were at highest risk. Methods: We ascertained 18 people with active epilepsy identified in a community-based registry of sudden cardiac arrest (SCA) with ECG-confirmed VT/VF (cases). We compared them with 470 individuals with VT/VF without epilepsy (VT/VF controls) and 54 individuals with epilepsy without VT/VF (epilepsy controls). Data on comorbidity, epilepsy severity, and medication use were collected and entered into (conditional) logistic regression models to identify determinants of VT/VF in epilepsy. Results: In most cases, there was an obvious (10/18) or presumed cardiovascular cause (5/18) in view of preexisting heart disease. In 2 of the 3 remaining events, near–sudden unexpected death in epilepsy (SUDEP) was established after successful resuscitation. Cases had a higher prevalence of congenital/inherited heart disease (17% vs 1%, p = 0.002), and experienced VT/VF at younger age (57 vs 64 years, p = 0.023) than VT/VF controls. VT/VF in cases occurred more frequently at/near home (89% vs 58%, p = 0.009), and was less frequently witnessed (72% vs 89%, p = 0.048) than in VT/VF controls. Cases more frequently had clinically relevant heart disease (50% vs 15%, p = 0.005) and intellectual disability (28% vs 1%, p epilepsy controls. Conclusion: Cardiovascular disease rather than epilepsy characteristics is the main determinant of VT/VF in people with epilepsy in the community. SCA and SUDEP are partially overlapping disease entities. PMID:26092917

  6. Comparative Simulation Study on Synchronous Generators Sudden Short Circuits

    Directory of Open Access Journals (Sweden)

    Lucian Lupşa-Tătaru

    2009-01-01

    Full Text Available Although of a great extent in time, the research works directed at studying transients in synchronous generators have not yet provided fully sufficient comparative studies in respect to sudden short circuits of the machine. The present paper puts forward novel and comprehensive process models for dynamic simulation of short circuit faults of initially unloaded synchronous generators, using the generalized d-q-0 mathematical model as starting point in derivation. Distinct from the time-domain analysis, the technique proposed here allows an effective comparative overview by employing a specialized procedure to perform repeated time-domain simulations accompanied by peak values recording for the various circumstances. The time consuming matrix numerical inversion at each step of integration, usually performed when selecting currents as state variables, is eliminated by advancing the process models in a convenient split matrix form that allows the symbolic processing. Also, the computational efficiency is being increased by introducing a set of auxiliary variables common to different state equations. The models derivation is carried out without altering the structural equations of the generalized d-q-0 mathematical model of synchronous generators whilst the simulation results are both compared and discussed in detail.

  7. PHYSICAL AND NUMERICAL MODELING OF ASD EXHAUST DISPERSION AROUND HOUSES

    Science.gov (United States)

    The report discusses the use of a wind tunnel to physically model the dispersion of exhaust plumes from active soil depressurization (ASD) radon mitigation systems in houses. he testing studied the effects of exhaust location (grade level vs. above the eave), as house height, roo...

  8. 基于氢气风险分析的A DS 手动卸压策略研究%Study on Depressurization Strategy by ADS Manually Considering Hydrogen Risk

    Institute of Scientific and Technical Information of China (English)

    朱伟; 李亚冰; 佟立丽; 曹学武

    2015-01-01

    先进非能动压水堆设计采用自动卸压系统(ADS )对一回路进行卸压,严重事故下主控室可手动开启ADS ,缓解高压熔堆风险。然而ADS的设计特点可能导致氢气在局部隔间积聚,带来局部氢气风险。本文基于氢气负面效应考虑,对利用ADS进行一回路卸压的策略进行研究,为严重事故管理提供技术支持。选取全厂断电始发的典型高压熔堆严重事故序列,利用一体化事故分析程序,评估手动开启第1~4级ADS、手动开启第1~3级ADS、手动开启第4级ADS 3种方案的卸压效果,并分析一回路卸压对安全壳局部隔间的氢气负面影响。研究结果表明,3种卸压方案均能有效降低一回路压力。但在氢气点火器不可用时,开启第1~3级ADS以及开启第1~4级ADS卸压会引起内置换料水箱隔间氢气浓度迅速增加,可能导致局部氢气燃爆。因此,基于氢气风险考虑,建议在实施严重事故管理导则一回路卸压策略时优先考虑采用第4级ADS进行一回路卸压。%For advanced passive pressurized water reactor ,the automatic depressuriza‐tion system (ADS ) can be applied to depressurize the reactor coolant system (RCS ) . T he main control room can manually open ADS to mitigate the risk of overpressure dur‐ing severe accidents .However ,the design characteristics of ADS may cause hydrogen releasing into the containment .Accumulating in the containment may cause hydrogen hazard in containment .Against this background ,the RCS depressurization strategy in severe accidents was analyzed and its negative impact standing from hydrogen risk to make suggestion to severe accident management was evaluated .The station black out accident was selected and analyzed with integral severe accident analysis code .Three different depressurization schemes were discussed on both depressurization effect and hydrogen risk .The hydrogen distribution and risk in different

  9. Some Challenges Posed by Coal Bed Methane Regional Assessment Modeling.

    Science.gov (United States)

    Moore, Catherine R; Doherty, John; Howell, Stephen; Erriah, Leon

    2015-01-01

    Coal measures (coal bearing rock strata) can contain large reserves of methane. These reserves are being exploited at a rapidly increasing rate in many parts of the world. To extract coal seam gas, thousands of wells are drilled at relatively small spacing to depressurize coal seams to induce desorption and allow subsequent capture of the gas. To manage this process effectively, the effect of coal bed methane (CBM) extraction on regional aquifer systems must be properly understood and managed. Groundwater modeling is an integral part of this management process. However, modeling of CBM impacts presents some unique challenges, as processes that are operative at two very different scales must be adequately represented in the models. The impacts of large-scale gas extraction may be felt over a large area, yet despite the significant upscaling that accompanies construction of a regional model, near-well conditions and processes cannot be ignored. These include the highly heterogeneous nature of many coal measures, and the dual-phase flow of water and gas that is induced by coal seam depressurization. To understand these challenges, a fine-scale model was constructed incorporating a detailed representation of lithological heterogeneity to ensure that near-well processes and conditions could be examined. The detail of this heterogeneity was at a level not previously employed in models built to assess groundwater impacts arising from CBM extraction. A dual-phase reservoir simulator was used to examine depressurization and water desaturation processes in the vicinity of an extractive wellfield within this fine-scale model. A single-phase simulator was then employed so that depressurization errors incurred by neglecting near-well, dual-phase flow could be explored. Two models with fewer lithological details were then constructed in order to examine the nature of depressurization errors incurred by upscaling and to assess the interaction of the upscaling process with the

  10. Hearing Recovey in Patients Suffering Sudden Deafness

    Directory of Open Access Journals (Sweden)

    Parviz Eslami

    1992-04-01

    Full Text Available The study included 80 patients treated for sudden deafness over the last 5-7 years. Case history, laboratory findings, pure-tone audiogram and electronystagmography (ENG findings were noted. If any abnormalities had been recorded in ENG studies, the studies were redone. ORL status was redefined and audiograms were obtained in all patients. When becoming ill, the 80 patients had not differed from the normal population in common cardiovascular risk factors. None of them had had signs of viral infection (paired serum samples had been taken at 2-week intervals; routine examinations had been done for common viral antigens. As many as 31 of the 80 patients with acute hearing loss had had abnormalities such as spontaneous nystagmus (PN, hypoexcitability (HE and directional preponderance (DP in the bithermal caloric tests (+44 degrees C, + 30 degrees C of their ENG studies. Twenty of the 31 patients still had abnormal ENG studies after 5-7 years. Only 1 subject had positional nystagmus, and none had subjective vertigo. Patients with an abnormal ENG study showed a poor recovery of the speech reception threshold, whereas those with a normal ENG study showed slightly significant (p less than 0.05 recovery.

  11. Weather conditions and sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Kateri Maria

    2002-07-01

    Full Text Available Abstract Background Climatic or meteorological condition changes have been implicated in the pathogenesis of Idiopathic Sudden Sensorineural Hearing Loss (ISSHL. We investigated the seasonal distribution of ISSHL and evaluated the influence of meteorological parameters (such as temperature, humidity, and atmospheric pressure, their variation and covariation on the incidence of the disease. Methods A total of 82 cases of ISSHL, admitted to our department over a five-year period, were enrolled in the study. Seasonal distribution of the disease was investigated by dividing the year in four seasons. Meteorological data included daily values of 13 distinct parameters recorded at the meteorological station of the University of Ioannina during this period. A relationship between each meteorological variable and the incidence of ISSHL was investigated by applying (χ2 test on data from 13 contingency tables as well as by using logistic regression and t-test approaches. In addition, the influence of different weather types on the incidence of ISSHL was investigated using Cluster Analysis in order to create eight clusters (weather types characteristic for the prefecture of Ioannina. Results The results of the study could not indicate any seasonal distribution of the disease. The incidence of ISSHL could not be significantly correlated either to any distinct meteorological parameter or to any specific weather type. Conclusions Meteorological conditions, such as those dominating in the Northwestern Greece, and/or their changes, have no proven effect on the incidence of ISSHL.

  12. Dummies and the sudden infant death syndrome.

    Science.gov (United States)

    Mitchell, E A; Taylor, B J; Ford, R P; Stewart, A W; Becroft, D M; Thompson, J M; Scragg, R; Hassall, I B; Barry, D M; Allen, E M

    1993-01-01

    The association between dummy use and sudden infant death syndrome (SIDS) was investigated in 485 deaths due to SIDS in the postneonatal age group and compared with 1800 control infants. Parental interviews were completed in 87% of subjects. The prevalence of dummy use in New Zealand is low and varies within New Zealand. Dummy use in the two week period before death was less in cases of SIDS than in the last two weeks for controls (odds ratio (OR) 0.76, 95% confidence interval (CI) 0.57 to 1.02). Use of a dummy in the last sleep for cases of SIDS or in the nominated sleep for controls was significantly less in cases than controls (OR 0.44, 95% CI 0.26 to 0.73). The OR changed very little after controlling for a wide range of potential confounders. It is concluded that dummy use may protect against SIDS, but this observation needs to be repeated before dummies can be recommended for this purpose. If dummy sucking is protective then it is one of several factors that may explain the higher mortality from SIDS in New Zealand than in other countries, and may also explain in part the regional variation within New Zealand. PMID:8503676

  13. Cardiac Causes of Sudden Infant Death

    Directory of Open Access Journals (Sweden)

    Fatih Aygün

    2014-08-01

    Full Text Available The mechanism and causes of sudden infant death syndrome (SIDS is still remains its mystery. The pathophysiology of SIDS is not clear. Sleeping in prone position is thought to contribute to pathophysiology. Schwartz was the first physician suggesting that SIDS can be associated with heart and autonomic nervous system. Congenital long QT syndrome may trigger SIDS by causing ventricular tachycardia. Normal cardiac rhythm is regulated by ion channels and specific proteins, but genetical analyses clearly demonstrated that 5 ion channel genes were responsible for rare arrhythmias. The infections, fever and sleeping in prone position can increase the risk of long QT syndrome in babies having mutations in cardiac ion channels. In this review we tried to draw attention to SIDS as an important cause of death in childhood period and association of SIDS with long QT syndrome which is not necessarily noticed by physicians. (The Jo­ur­nal of Cur­rent Pe­di­at­rics 2014;1:37-42

  14. Sudden unexpected death associated with lymphocytic thyroiditis.

    Science.gov (United States)

    Vestergaard, Vibeke; Drostrup, Dorthe Høj; Thomsen, Jørgen L

    2007-04-01

    A forensic autopsy study comprising 125 cases was carried out retrospectively in order to evaluate pathological changes in the thyroid gland in different groups of death. The five groups selected consecutively were: (i) opiate addicts who died from an overdose, (ii) alcoholics who died as a result of their alcohol abuse, (iii) cases of fatal poisoning other than opiate addicts, (iv) unknown cause of death and (v) controls without prior disease. Tissue samples from the thyroid gland were cut and stained with haematoxylin and eosin and van Gieson. Histology examinations were subsequently performed blind with semiquantitative assessment of the following six parameters: (a) height of the follicular epithelium, (b) the amount of lymphocytes, (c) the presence of plasma cells, (d) hyperplastic follicular changes, (e) oxyphilic changes, and (f) fibrosis. The most striking result was the finding of extensive lymphocytic infiltration of the thyroid parenchyma in five of the 124 cases, of which four belonged in the group of 'unknown cause of death'. This discovery leads to reflections regarding lymphocytic thyroiditis as a cause of death, either by itself or in combination with other disorders. Silent (painless) thyroiditis, especially, is easily overlooked at autopsy as there are no macroscopic changes and often no prior symptoms or history of thyroid disease pointing towards this condition. Analyses of thyroid hormones are unreliable in predicting endocrine status in life. Routine microscopy of the thyroid gland is therefore advocated in cases of sudden unexpected death in order to diagnose thyroid disease, in particular silent (painless) thyroiditis.

  15. A clinical study of sudden deafness.

    Science.gov (United States)

    Zhang, Xiaotong; Xu, Xinda; Ma, Weijun; Zhang, Qing; Tong, Busheng; Yu, Hong; Xu, Min; Ren, Tianying; Rosenhall, Ulf; Anniko, Matti; Duan, Maoli

    2015-01-01

    Sudden Sensorineural Hearing Loss (SSHL) was commonly seen in middle aged people. Tinnitus was reported by 87.2% of the patients, and dizziness or vertigo were reported by 48.5%. The most common concomitant disorder of SSHL was hyperlipidemia. A retrospective register study with SSHL was performed in Xi'an, China, from 2000-2009. Of 617 inpatients, the right ear was affected in 267 cases, the left ears in 282 cases, and both ears in 68 cases. The most common age of patients was 41-50 years. There were 20.4% SSHL patients with hypertension, coronary artery disease, or diabetes, and 49.6% patients with hyperlipidemia. Auditory Brainstem Responses (ABR) were performed in 460 patients (504 ears) before treatment, and the ABR threshold of 56.4% ears was > 90 dB. The constituent ratio of patients with an ABR threshold over 90 dB was greater in the vertigo group than the other group. CT and/or MRI scans were available in 277 cases, of which 40 cases (14.4%) were abnormal.

  16. Cardiac channelopathies and sudden infant death syndrome.

    Science.gov (United States)

    Tfelt-Hansen, Jacob; Winkel, Bo Gregers; Grunnet, Morten; Jespersen, Thomas

    2011-01-01

    Sudden infant death syndrome (SIDS) is always a devastating and unexpected occurrence. SIDS is the leading cause of death in the first 6 months after birth in the industrialized world. Since the discovery in 1998 of long QT syndrome as an underlying substrate for SIDS, around 10-20% of SIDS cases have been proposed as being caused by genetic variants in either ion channel or ion channel-associated proteins. Until now, 10 cardiac channelopathy susceptibility genes have been found to be implicated in the pathogenesis of SIDS. Four of the genes encode cardiac ion channel α-subunits, 3 genes encode ion channel β-subunits, and 3 genes encode other channel-interacting proteins. All 10 genes have been associated with primary electrical heart diseases. SIDS may hereby be the initial symptom of rare primary electric channelopathies such as long QT, short QT and Brugada syndrome, as well as catecholaminergic polymorphic ventricular tachycardia. In this review we describe the functional role of sodium, potassium and calcium channels in propagation, depolarization and repolarization in the context of the 4 arrhythmogenic diseases reported to be associated with SIDS. Lastly, the possibility of postmortem genetic testing and potential recommendations on how to deal with family members are discussed. Copyright © 2011 S. Karger AG, Basel.

  17. [Sensitivity and specificity of first-level screening in the identification of patients at risk for sudden cardiac death].

    Science.gov (United States)

    Delise, Pietro; Sitta, Nadir; Allocca, Giuseppe; Marras, Elena; Lanari, Emanuela

    2008-10-01

    Since 1971, in Italy every citizen engaged in competitive sports activity must periodically undergo preventive medical examinations to ascertain eligibility for sports participation. The medical examination includes rest and effort ECG. The Italian model has a very good sensitivity in identifying most pathologies at risk of sudden death particularly in the young (hypertrophic cadiomyopathy, arrhythmogenic right ventricular disease, chanelopathies). In this model, the ECG is very important, being able to disclose cardiac anomalies in most cases. The application of the Italian screening model has progressively reduced the incidence of sudden death in athletes.

  18. Social phobia with sudden onset-Post-panic social phobia?

    DEFF Research Database (Denmark)

    Kristensen, Ann Suhl; Mortensen, Erik Lykke; Mors, Ole

    2008-01-01

    Overlap between social phobia (SP) and panic disorder (PD) has been observed in epidemiological, family, and challenge studies. One possible explanation is that some cases of SP develop as a consequence of a panic attack in a social situation. By definition, these cases of SP have sudden onset....... It is hypothesized that patients with SP with sudden onset are more similar to patients with comorbid SP and PD than to patients with SP without sudden onset regarding age of onset, extraversion, and prevalence of anxiety symptoms. One hundred and eighty-two patients with a lifetime diagnosis of PD and/or SP were...

  19. Unilateral sudden hearing loss: a rare symptom of Moyamoya disease.

    Science.gov (United States)

    Gül, Fatih; Berçin, Sami; Müderris, Togay; Yalçıner, Gökhan; Ünal, Özkan; Kırış, Muzaffer

    2016-01-01

    A 38-year-old female patient experienced a sudden onset of unilateral sensorineural hearing loss due to Moyamoya disease. A detailed summary of audiological and neurological findings indicated that the sudden hearing loss might be due to Moyamoya disease resulting in occlusion of posterior and middle cerebral arteries. Intravenous prednisolone and trimetazidine dihydrochloride may improve hearing thresholds and speech understanding. To our knowledge, this is the first article in the literature reporting a case of sudden hearing loss as the first manifestation of Moyamoya disease in a young adult.

  20. Histological findings in unclassified sudden infant death, including sudden infant death syndrome.

    Science.gov (United States)

    Liebrechts-Akkerman, Germaine; Bovée, Judith V M G; Wijnaendts, Liliane C D; Maes, Ann; Nikkels, Peter G J; de Krijger, Ronald R

    2013-01-01

    Our objective was to study histological variations and abnormalities in unclassified sudden infant death (USID), including sudden infant death syndrome (SIDS), in The Netherlands. Two hundred Dutch USID cases between 1984 and 2005 were identified. The histology slides and autopsy reports of 187 cases were available for systematic review, including brain autopsy in 135 cases. An explanation for the cause of death in 19 patients (10.2%) was found. Twelve patients had bronchopneumonia, 3 showed extensive aspiration, 2 had signs of a metabolic disorder, 1 had sepsis, and 1 had meningitis. Frequent nonspecific findings were congestion (66%), edema (47%), small hemorrhages (18%), and lymphoid aggregates (51%) in the lungs; congestion of the liver (23%); and asphyctic bleeding in the kidney (44%), adrenal gland (23%), and thymus (17%). Statistical associations were found for infection with starry sky macrophages in the thymus (P  =  0.004), with calcification (P  =  0.023), or with debris in the Hassal's corpuscles (P  =  0.034). In this study, in 10.2% of cases the histological findings were incompatible with SIDS or USID. Furthermore, several frequent nonspecific histological findings in the thymus that point toward an infection were found.

  1. [Sport-related sudden death and its prevention].

    Science.gov (United States)

    Brion, Richard

    2010-10-01

    Sudden death of sportspersons is frequently in the news but is relatively uncommon when the total number of sudden deaths is taken into account (1500 vs 40 000 per year in France for example). Sport-related sudden death is often due to an unrecognized or underestimated cardiovascular disorder. The immediate causes of this dramatic event are age-dependent. Before 35, the most frequent causes are hypertrophic cardiomyopathy and arythmogenic right ventricular cardiomyopathy, while complications of coronary atheroma predominate later. Prevention begins with screening, which remains imperfect. Patients with cardiovascular disorders at risk of sudden death must adapt their sports activities accordingly. Knowledge of life-saving first-aid procedures by those supervising sports activities can improve the prognosis.

  2. Prevalence of risk factors for sudden cardiac death in competitive ...

    African Journals Online (AJOL)

    Prevalence of risk factors for sudden cardiac death in competitive South African student ... personal and family history, physical examination (including blood pressure, ... Significant correlations were found between gender and family history of ...

  3. Pathophysiology of reversible sudden deafness--epidemiological study.

    Directory of Open Access Journals (Sweden)

    Ohsaki,Katsuichiro

    1983-04-01

    Full Text Available Many aspects of the etiology and pathophysiology of reversible sudden deafness remain obscure. In order to better understand the pathophysiology of reversible sudden deafness we compared the results of two therapies which have different mechanisms of action. The results of therapy with tranexamic acid alone in 49 cases (57 ears of sudden deafness were compared with the results of treatment with so-called antisludging agents in 65 cases (69 ears using the chi square contingency test. The same therapeutic effect was observed in both groups despite the different modes of chemical action of the two therapeutics. A series of processes involving an increase in permeability of vascular walls and related edema, and extravascular red cell oozing due to hypoxia or anoxia leading to tissue damage in the inner ear seem to be important factors in the etiology and pathophysiology of reversible sudden deafness.

  4. Intrathoracic cystic hygroma with sudden respiratory distress mimicking pneumonia

    Directory of Open Access Journals (Sweden)

    Umesh Goneppanavar

    2012-01-01

    Full Text Available Benign cystic lesions such as cystic hygroma commonly manifest as progressively increasing swelling in the neck with or without compression effects. Rarely, they present with sudden respiratory distress in instances such as infection or haematoma resulting in a sudden increase in the size of the tumour. We present a seven month old child with sudden onset respiratory distress without any obvious neck swelling. The chest X ray findings correlated with the history and were suggestive of right upper lobe pneumonia that leads to a wrong diagnosis of aspiration pneumonia. However, presence of a deviated trachea in the neck raised a suspicion of possible mass. Computed tomogram showed a large cystic mass in the right upper mediastinum with tracheal collapse. We caution intensivists and paediatricians that sudden respiratory distress in infants in the absence of obvious neck swelling does not rule out possibility of intrathoracic tumour.

  5. Psychosocial Aspects of the Sudden Infant Death Syndrome ("Cot Death").

    Science.gov (United States)

    Bluglass, Kerry

    1981-01-01

    Reviews literature on reactions of parents and siblings to Sudden Infant Death Syndrome (SIDS). The prospects for prolonged, adverse reactions are considered, and professional concerns regarding abnormal adaptation are noted. (Author/DB)

  6. Is composite noise necessary for sudden death of entanglement?

    Science.gov (United States)

    Yashodamma, K. O.; Sudha

    The finite time disentanglement or entanglement sudden death, when only one part of the composite system is subjected to a single noise, is examined. While it is shown that entanglement sudden death can occur when a part of the entangled mixed state is subjected to either amplitude noise or phase noise, local action of either of them does not cause entanglement sudden death in pure entangled states. In contrast, depolarizing noise is shown to have an ability to cause sudden death of entanglement even in pure entangled states, when only one part of the state is exposed to it. The result is illustrated through the action of different noisy environments individually on a single qubit of the so-called X class of states and an arbitrary two-qubit pure state.

  7. Research on sudden environmental pollution public service platform construction based on WebGIS

    Science.gov (United States)

    Bi, T. P.; Gao, D. Y.; Zhong, X. Y.

    2016-08-01

    In order to actualize the social sharing and service of the emergency-response information for sudden pollution accidents, the public can share the risk source information service, dangerous goods control technology service and so on, The SQL Server and ArcSDE software are used to establish a spatial database to restore all kinds of information including risk sources, hazardous chemicals and handling methods in case of accidents. Combined with Chinese atmospheric environmental assessment standards, the SCREEN3 atmospheric dispersion model and one-dimensional liquid diffusion model are established to realize the query of related information and the display of the diffusion effect under B/S structure. Based on the WebGIS technology, C#.Net language is used to develop the sudden environmental pollution public service platform. As a result, the public service platform can make risk assessments and provide the best emergency processing services.

  8. Sudden Sensorioneural Hearing Loss and Autoimmune Systemic Diseases.

    Science.gov (United States)

    Rossini, Bruno Almeida Antunes; Penido, Norma de Oliveira; Munhoz, Mario Sergio Lei; Bogaz, Eduardo Amaro; Curi, Renata Souza

    2017-07-01

    Introduction  Several authors have demonstrated the relationship between sudden sensorineural hearing loss (SNHL) and systemic autoimmune diseases (SAD). Immune-mediated SNHL can rarely present as unilateral sudden SNHL and manifests itself in the contralateral ear only after years. It presents clinical relevance for being one of the few SNHL that may be reversible given that early and appropriate treatment is applied. Objective  The objective of this study is to describe the clinical presentations and audiological findings from patients with idiopathic sudden SNHL and SAD associated with a probable diagnosis of immune-mediated SNHL. Furthermore, we strive to estimate the prevalence of SAD in patients with sudden SNHL. Methods  This is an observational retrospective cohort. We have selected and studied patients with SAD. Revision of available literature on scientific repositories. Results  We evaluated 339 patients with sudden SNHL. Among them, 13 (3.83%) patients suffered from SAD. Three patients had bilateral involvement, a total of 16 ears. We evaluate and describe various clinical, epidemiological, and audiological aspects of this sample. Conclusion  In our sample of patients with sudden SNHL, the prevalence of SAD was found relevant. The majority had tinnitus and dizziness concomitant hearing loss, unilateral involvement and had experienced profound hearing loss at the time of the installation. In spite of instituted treatment, most cases showed no improvement in audiometric thresholds. Apparently, patients with sudden SNHL and SAD have a more severe initial impairment, higher percentage of bilateral, lower response to treatment, and worse prognosis than patients with sudden SNHL of unknown etiology.

  9. Sudden infant death syndrome: methodological and patogenetical types of diagnosis

    Directory of Open Access Journals (Sweden)

    B.I. Glukhovets

    2011-01-01

    Full Text Available The review presents an analysis of literature data on pathogenesis of sudden infant death syndrome (SIDS in comparison with author’s experience of infants dead in home. Diagnostic significance of qualified autopsy examinations in analysis of infants’ death is shown. Frequent combination of morphogenetic cardiopathy and early signs of atrial myocarditis can be estimated as pathogenetic basis of SIDS.Key words: sudden infant death syndrome, morphogenetic cardiopathy, atrial myocarditis.

  10. Mutations in calmodulin cause ventricular tachycardia and sudden cardiac death

    DEFF Research Database (Denmark)

    Nyegaard, Mette; Overgaard, Michael Toft; Søndergaard, Mads

    2012-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a devastating inherited disorder characterized by episodic syncope and/or sudden cardiac arrest during exercise or acute emotion in individuals without structural cardiac abnormalities. Although rare, CPVT is suspected to cause...... calmodulin-binding-domain peptide at low calcium concentrations. We conclude that calmodulin mutations can cause severe cardiac arrhythmia and that the calmodulin genes are candidates for genetic screening of individual cases and families with idiopathic ventricular tachycardia and unexplained sudden cardiac...

  11. Bilateral Sudden Hearing Loss in Waldenstrom's Macroglobulinemia: MR Appearance.

    Science.gov (United States)

    Shibata, Dean K; Johnston, S Claiborne

    2006-01-01

    A 46 year-old man with acquired immunodeficiency syndrome presented with sudden development of vertigo and tinnitus and then simultaneous, bilateral, profound, sudden hearing loss. Magnetic resonance imaging showed bilateral high signal within the cochlea, vestibule, and portions of the semicircular canals on the non-enhanced T1-weighted images, most consistent with recent hemorrhage into the otic labyrinth. Serum analysis and bone-marrow biopsy led to diagnosis of Waldenstrom's macroglobulinemia - a likely cause of the presumed hemorrhage.

  12. Control of Sudden Death of Entanglement by Transient Effects

    Institute of Scientific and Technical Information of China (English)

    Hunkar Kayhan

    2011-01-01

    We investigate the properties of entanglement between an isolated atom and a Jaynes-Cummings atom in the presence of transient effects. These effects are due to the modulation of the atom-field coupling whose explicit time-dependence is considered for the case of the linear sweep. We show that the sudden death of entanglement can be controlled by the transient effects. These effects can suppress the sudden death of entanglement in time.

  13. Oral steroid treatment for idiopathic sudden sensorineural hearing loss

    OpenAIRE

    Chen, Wei T.; Lee, Jui W.; Yuan, Chien H.; Chen, Rong F.

    2015-01-01

    Objectives: To describe the efficacy of long-term oral steroids in idiopathic sudden sensorineural hearing loss (ISSHL), and to explore potential prognosis factors, the relationship of hearing recovery outcome, and the recovery time-course in ISSHL. Methods: In this retrospective study, we analyzed 215 cases diagnosed with idiopathic unilateral sudden deafness between January 2003 and December 2012 at a regional hospital in southern Taiwan. All of them received oral steroid therapy and were f...

  14. Diabetes mellitus and sudden cardiac death: what are the data?

    Science.gov (United States)

    Bergner, Daniel W; Goldberger, Jeffrey J

    2010-01-01

    Diabetes mellitus has long been linked to an increased risk of sudden cardiac death. However, the magnitude of this association, and the mechanism accounting for this phenomenon, have not been precisely defined. In this review, we evaluate the epidemiological data pertaining to the association between diabetes mellitus and sudden cardiac death and discuss various proposed mechanisms that may account for this relationship. Potential factors contributing to the increased risk of sudden cardiac death observed in patients with diabetes mellitus include silent myocardial ischemia, autonomic nervous system dysfunction, abnormal cardiac repolarization, hypoglycemia, a hypercoaguable state secondary to diabetes mellitus, diabetic cardiomyopathy, and impaired respiratory response to hypoxia and hypercapnea. We conclude that diabetes mellitus does appear to be associated with an increased risk of sudden cardiac death. Although this increased risk is relatively modest, given the large number of diabetic patients worldwide, the absolute number of sudden cardiac deaths attributable to diabetes mellitus remains significant. Little evidence exists to support any specific mechanism(s) accounting for this association. Further investigation into the pathophysiology of sudden cardiac death in diabetes mellitus may yield improved risk stratification tools as well as identify novel therapeutic targets.

  15. Characterization of dynamical regimes and entanglement sudden death in a microcavity quantum dot system

    Energy Technology Data Exchange (ETDEWEB)

    Vera, Carlos A; Quesada M, Nicolas; Vinck-Posada, Herbert; Rodriguez, Boris A, E-mail: nquesada@pegasus.udea.edu.c [Instituto de Fisica, Universidad de Antioquia, Medellin, AA 1226 Medellin (Colombia)

    2009-09-30

    The relation between the dynamical regimes (weak and strong coupling) and entanglement for a dissipative quantum dot microcavity system is studied. In the framework of a phenomenological temperature model an analysis in both temporal (population dynamics) and frequency domain (photoluminescence) is carried out in order to identify the associated dynamical behavior. The Wigner function and concurrence are employed to quantify the entanglement in each regime. We find that sudden death of entanglement is a typical characteristic of the strong coupling regime.

  16. Computational fluid dynamics analysis of the initial stages of a VHTR air-ingress accident using a scaled-down model

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Tae K., E-mail: taekyu8@gmail.com [Nuclear Engineering Program, The Ohio State University, Columbus, OH 43210 (United States); Arcilesi, David J., E-mail: arcilesi.1@osu.edu [Nuclear Engineering Program, The Ohio State University, Columbus, OH 43210 (United States); Kim, In H., E-mail: ihkim0730@gmail.com [Nuclear Engineering Program, The Ohio State University, Columbus, OH 43210 (United States); Sun, Xiaodong, E-mail: sun.200@osu.edu [Nuclear Engineering Program, The Ohio State University, Columbus, OH 43210 (United States); Christensen, Richard N., E-mail: rchristensen@uidaho.edu [Nuclear Engineering Program, The Ohio State University, Columbus, OH 43210 (United States); Oh, Chang H. [Idaho National Laboratory, Idaho Falls, ID 83402 (United States); Kim, Eung S., E-mail: kes7741@snu.ac.kr [Idaho National Laboratory, Idaho Falls, ID 83402 (United States)

    2016-04-15

    Highlights: • Uncertainty quantification and benchmark study are performed to validate an ANSYS FLUENT computer model for a depressurization process in a high-temperature gas-cooled reactor. • An ANSYS FLUENT computer model of a 1/8th scaled-down geometry of a VHTR hot exit plenum is presented, which is similar to the experimental test facility that has been constructed at The Ohio State University. • Using the computer model of the scaled-down geometry, the effects of the depressurization process and flow oscillations on the subsequent density-driven stratified flow phenomenology are examined computationally. • The effects of the scaled-down hot exit plenum internal structure temperature on the density-driven stratified flow phenomenology are investigated numerically. - Abstract: An air-ingress accident is considered to be one of the design basis accidents of a very high-temperature gas-cooled reactor (VHTR). The air-ingress accident is initiated, in its worst-case scenario, by a complete break of the hot duct in what is referred to as a double-ended guillotine break. This leads to an initial loss of the primary helium coolant via depressurization. Following the depressurization process, the air–helium mixture in the reactor cavity could enter the reactor core via the hot duct and hot exit plenum. In the event that air ingresses into the reactor vessel, the high-temperature graphite structures in the reactor core and hot plenum will chemically react with the air, which could lead to damage of in-core graphite structures and fuel, release of carbon monoxide and carbon dioxide, core heat up, failure of the structural integrity of the system, and eventually the release of radionuclides to the environment. Studies in the available literature focus on the phenomena of the air ingress accident that occur after the termination of the depressurization, such as density-driven stratified flow, molecular diffusion, and natural circulation. However, a recent study

  17. A comprehensive study of oxidative stress in sudden hearing loss.

    Science.gov (United States)

    Gul, Fatih; Muderris, Togay; Yalciner, Gokhan; Sevil, Ergun; Bercin, Sami; Ergin, Merve; Babademez, Mehmet Ali; Kiris, Muzaffer

    2017-03-01

    Little is known about the association between idiopathic sudden sensorineural hearing loss (ISSNHL) and oxidative stress. We investigated changes in a wide range of oxidants and antioxidants to create a comprehensive picture of oxidative imbalance. In the peripheral blood of 50 ISSNHL patients and 50 healthy subjects, total oxidant status (TOS), total antioxidant status (TAS), paraoxonase (PON), thiol/disulphide levels were measured. Moreover, a global oxidative stress index, reflecting both oxidative and antioxidant counterparts, was also calculated. One-way analysis between oxidative markers and severity of hearing loss were evaluated. The ISSNHL patients showed significantly higher TOS levels than controls (6.02 ± 3.17 vs. 4.5 ± 2.22; p = 0.018). The oxidative index was also significantly higher in patients than controls (0.39 ± 0.19 vs. 0.3 ± 0.14; p = 0.035). TAS, PON, native thiol, and total thiol were not altered. There was no statistical significance between oxidative markers and severity of hearing loss. The binary logistic regression model revealed that disulphide and TOS were associated with ISSNHL. There are alterations in a wide array of oxidants and antioxidants, with balance shifting toward increased oxidative stress in ISSNHL. Our findings may suggest endothelial dysfunction in ISSNHL etiopathogenesis.

  18. Disrupted functional brain connectome in unilateral sudden sensorineural hearing loss.

    Science.gov (United States)

    Xu, Haibo; Fan, Wenliang; Zhao, Xueyan; Li, Jing; Zhang, Wenjuan; Lei, Ping; Liu, Yuan; Wang, Haha; Cheng, Huamao; Shi, Hong

    2016-05-01

    Sudden sensorineural hearing loss (SSNHL) is generally defined as sensorineural hearing loss of 30 dB or greater over at least three contiguous audiometric frequencies and within a three-day period. This hearing loss is usually unilateral and can be associated with tinnitus and vertigo. The pathogenesis of unilateral sudden sensorineural hearing loss is still unknown, and the alterations in the functional connectivity are suspected to involve one possible pathogenesis. Despite scarce findings with respect to alterations in brain functional networks in unilateral sudden sensorineural hearing loss, the alterations of the whole brain functional connectome and whether these alterations were already in existence in the acute period remains unknown. The aim of this study was to investigate the alterations of brain functional connectome in two large samples of unilateral sudden sensorineural hearing loss patients and to investigate the correlation between unilateral sudden sensorineural hearing loss characteristics and changes in the functional network properties. Pure tone audiometry was performed to assess hearing ability. Abnormal changes in the peripheral auditory system were examined using conventional magnetic resonance imaging. The graph theoretical network analysis method was used to detect brain connectome alterations in unilateral sudden sensorineural hearing loss. Compared with the control groups, both groups of unilateral SSNHL patients exhibited a significantly increased clustering coefficient, global efficiency, and local efficiency but a significantly decreased characteristic path length. In addition, the primary increased nodal strength (e.g., nodal betweenness, hubs) was observed in several regions primarily, including the limbic and paralimbic systems, and in the auditory network brain areas. These findings suggest that the alteration of network organization already exists in unilateral sudden sensorineural hearing loss patients within the acute period

  19. [The preliminary research of progress on sudden deafness with benign paroxysmal positional vertigo patients].

    Science.gov (United States)

    Zhou, Xiaowei; Yu, Youjin; Zhao, Yuanxin; Wang, Yuejian; Liu, Zhen; Liu, Qiuling

    2014-08-01

    To investigate the prognosis of sudden deafness patients with benign paroxysmal positional vertigo (BPPV). The clinical data of 24 sudden deafness patients with BPPV was analyzed. The outcome of 125 sudden deafness patients without BPPV at the same time was compared. Hearing improvement after three months treatment was 41.67% and 72.80% in sudden deafness patients with BPPV and sudden deafness patients without BPPV, respectively. The difference was statistically significant (Psudden deafness patients with BPPV is worse than that in sudden deafness patients without BPPV. BPPV may predict a poor hearing outcome in sudden deafness.

  20. [Clinical analysis of short-term efficacy in senile sudden deafness].

    Science.gov (United States)

    Zhang, Xiaojun; Zhou, Jianyong; Tan, Guopeng; Jieyu, L V; Yan, Feipeng

    2013-11-01

    To analysis the short-term medicinal treating effects in senile sudden deafness. According the age. The sudden deafness patients were divided into to groups, older age-group (age > or = 60, a total of 70 cases), control group (age sudden deafness patients (disease time 7 days) was 38.89%. There was statistical difference (P sudden deafness patients was 49.9%; the senile sudden deafness patients which following moderate deafness (hearing threshold sudden deafness patients. As soon as possible to improve peripheral vascular microcirculation, the prognosis could be improve conspicuously the prognosis of the senile sudden deafness patients were worse than the young patients.

  1. Lagrangian simulation of deposition of CO2 gas-solid sudden expansion flow

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Freezing and blockage resulting from the deposition of solid CO2 formed because of sudden expansion of the downstream pipe during the release of CO2 through safety valves,will endanger the protected equipment.To overcome this problem,the characteristics of the CO2 gas-solid sudden expansion flow are studied by using the disperse Lagrangian model.A comparison of the calculated deposition of the solid CO2 with the experimental results shows that they are in reasonable agreement.The simulation results show that the size of the solid CO2 formed should not be in the range of 0.04-0.07 mm (St number 3.2-9.8).This can be achieved by using an appropriate flow cross section of the safety valve.

  2. Idiopathic sudden sensorineural hearing loss: vascular or viral?

    Science.gov (United States)

    Linthicum, Fred H; Doherty, Joni; Berliner, Karen I

    2013-12-01

    To demonstrate that sudden sensorineural hearing loss is possibly of viral origin rather than vascular. The histopathologic morphology in 7 temporal bones with known vascular impairment due to surgical interventions was compared with that of 11 bones with a history of idiopathic sudden sensorineural hearing loss (ISSNHL). Attention was paid to the spiral ligament, stria vascularis, organ of Corti hair cells, tectorial membrane, ganglion cell population, and degree of perilymph fibrosis and the auditory nerve. A temporal bone laboratory that has been in operation for more than 50 years and includes a database consisting of clinical and histopathological information that facilitates quantitative and qualitative analysis. Eight hundred forty-nine individuals who pledged their temporal bones for scientific study, of which 18 were selected for this study by means of the database criteria of sudden sensorineural hearing loss and postmiddle fossa and retro sigmoid sinus tumor removal or vestibular nerve section. Sudden sensorineural hearing loss bones exhibited no perilymph fibrosis compared with 6 of 7 vascular cases with fibrosis (P ≤ .001), exhibited less loss of ganglion cells (P ≤ .026), exhibited greater survival of spiral ligament (P ≤ .029), and averaged twice the survival of hair cells and more widespread tectorial membrane abnormalities. Analysis of human temporal bones from patients with a sudden sensorineural hearing loss does not support a vascular insufficiency but is more suggestive of a viral etiology.

  3. Strategies for the prevention of sudden cardiac death during sports.

    Science.gov (United States)

    Corrado, Domenico; Drezner, Jonathan; Basso, Cristina; Pelliccia, Antonio; Thiene, Gaetano

    2011-04-01

    Sudden cardiac death of a young athlete is the most tragic event in sports and devastates the family, the sports medicine team, and the local community. Such a fatality represents the first manifestation of cardiac disease in up to 80% of young athletes who remain asymptomatic before sudden cardiac arrest occurs; this explains the limited power of screening modalities based solely on history and physical examination. The long-running Italian experience showed that electrocardiogram (ECG) screening definitively improves the sensitivity of pre-participation evaluation for heart diseases and substantially reduces the risk of death in the athletic field (primary prevention). However, some cardiac conditions, such as coronary artery diseases, present no abnormalities on 12-lead ECG. Moreover, cardiac arrest due to non-penetrating chest injury (commotio cordis) cannot be prevented by screening. This justifies the efforts for implementing programmes of early external defibrillation of unpredictable arrhythmic cardiac arrest. This article reviews the epidemiology of sudden cardiac arrest in the athlete in terms of incidence, sport-related risk, underlying causes, and the currently available prevention programmes such as pre-participation screening and early external defibrillation by using automated external defibrillators. The best strategy is to combine synergistically primary prevention of sudden cardiac death by pre-participation identification of athletes affected by at-risk cardiomyopathies and secondary prevention with back-up defibrillation of unpredictable sudden cardiac arrest on the athletic field.

  4. Effect of retreatment on the end-stage sudden deafness.

    Science.gov (United States)

    Suoqiang, Zhai; Ning, Yu; Guiliang, Zheng; Yuhua, Zhu; He, Qin

    2012-03-01

    Microcirculatory disturbance of inner ear is probably one of the important etiological factors of sudden deafness. The purpose of this study was to evaluate the effect of retreatment on the end-stage sudden deafness. For this purpose, the patients who met with the criteria for sudden deafness and showed poor response to conventional therapy over 2 months were assigned randomly to the retreatment group. Pure tone audiometry was conducted before and after retreatment among the 103 patients (112 ears). Sodium bicarbonate and dexamethasone were injected by intravenous drip for 2 days and batroxobin 5BU for 6 days. Data were analyzed using analysis of variance and t test to determine the efficacy of retreatment. These data show that the efficacy rate in retreatment group was 46.43% and the difference between before and after retreatment was significant (P sudden deafness could improve the audition of the patients and should be valuable in clinics. In this regard, the combination of sodium bicarbonate and dexamethasone proved a rational therapeutic regimen for the end-stage sudden deafness. However, further large-size multicenter studies will be required for independent validation of these findings.

  5. N-acetylcysteine as a single therapy for sudden deafness.

    Science.gov (United States)

    Chen, Chao-Hsien; Young, Yi-Ho

    2017-01-01

    Like NAC ameliorates hearing loss from acoustic trauma in the inner ear, NAC may also rescue hearing loss from sudden deafness confined to the inner ear. This study assesses the effect of N-acetyl-L-cysteine (NAC) as a single therapy for sudden deafness. Thirty-five sudden deafness patients with neither systemic disorders nor central signs in electronystagmography were treated with NAC alone and assigned to Group A. For comparison, another 35 sudden deafness patients treated by corticosteroids and plasma expander were assigned to Group B. There were no significant differences between the two groups in terms of age, sex, laterality, and pre-treatment mean hearing level. All patients underwent an inner ear test battery comprising audiometry, and ocular vestibular-evoked myogenic potential (oVEMP), cervical VEMP (cVEMP), and caloric tests. Groups A and B did not significantly differ in the pre-treatment mean hearing level, and percentages of abnormal oVEMP, cVEMP, and caloric tests, indicating that the involvement severity of sudden deafness between the two groups was similar. However, Group A (43 ± 27 dB) showed significantly greater mean hearing gain than Group B (21 ± 28 dB), and Group A (91%) revealed better improved rate of hearing than Group B (57%).

  6. Time-series analysis of the relationship between air quality,temperature, and sudden unexplained death in Beijing during 2005-2008

    Institute of Scientific and Technical Information of China (English)

    TIAN Zhao-xing; ZHANG Yan-shen; YAN Wei; ZHAO Wen-kui

    2012-01-01

    Background There is a yearly increase in the rate of sudden unexplained death (SUD),even through extensive physical examination and the testing of a large number of biomarkers,the cause of sudden death in patients previously in good health cannot be fully determined.During clinical practice,a spatial aggregation phenomenon has been observed in the incidence of sudden unexplained death.Previous research has shown that environmental factors,such as air pollution,weather conditions,etc.,have a significant impact on human health.In the wake of the continuous environmental damage,the relationship between environmental factors and sudden unexplained death still needs to be studied.To study the relationship between sudden unexplained death and air quality and temperature,commonly used markers such as particulate matter of aerodynamic diameter <10 μm (PM10),daily average concentration of the gaseous pollutants sulfur dioxide (SO2) and nitrogen dioxide (NO2),and the daily average temperature were investigated.Methods The methods include collecting the data of sudden unexplained death; air quality monitoring; meteorological monitoring from January 1,2005 to December 31,2008; utilizing generalized additive models (GAM); controlling the influential factors such as secular trend,seasonal trend,and Sunday dummy variable; and analyzing the correlation between daily inhalable particle concentration,daily average temperature,and the number of daily SUD.Results There was no statistical significance between the daily inhalable particle and daily incidence of sudden unexplained death.Incidence rate of sudden unexplained death had nonlinear positive correlation with daily temperature.When the temperature was 5℃ above the daily average temperature,the daily incidence of sudden unexplained death went up with the rising temperature.Conclusion Temperature may be one of the key risk factor or precipitating factor of SUD.

  7. The etiology of idiopathic sudden sensorineural hearing loss - Experimental herpes simplex virus infections of the inner ear

    NARCIS (Netherlands)

    Stokroos, RJ; Albers, FWJ; Schirm, J

    1998-01-01

    Hypothesis: Experimentally induced herpes simplex virus type 1 (HSV-1) labyrinthitis provides a suitable model for idiopathic sudden sensorineural hearing loss (ISSHL). Background: Viral labyrinthitis has been postulated to play a role in the pathophysiology of ISSHL. Circumstantial evidence is pain

  8. Bilateral sudden sensorineural hearing loss in Staphylococcus aureus endocarditis.

    Science.gov (United States)

    Lau, Joanne Wai Ling; Ceranic, Borka; Harris, Robert; Timehin, Elwina

    2015-09-14

    This case highlights the diagnostic challenges in patients presenting with bilateral sudden sensorinueral hearing loss (SNHL). The aetiology of bilateral sudden SNHL may span several medical disciplines. Therefore, clinicians should be mindful of such presentations, and consider aetiologies beyond otological and neurological causes. We present a case of a previously healthy 51-year-old woman who presented with coryzal symptoms and sudden audiovestibular failure. Examination revealed fever, tachycardia, bilateral profound hearing loss and nystagmus. Following investigations, an initial working diagnosis of vasculitis was made. Later, blood cultures revealed methicillin-sensitive Staphylococcus aureus (MSSA) and a transoesophageal echocardiogram confirmed endocarditis. The patient made a good recovery, but the hearing loss was permanent and managed with a cochlear implant.

  9. Sudden death due to inhalant abuse in youth: Case report

    Directory of Open Access Journals (Sweden)

    Ramazan Akcan

    2010-06-01

    Full Text Available Intentional inhalation or abuse of volatile substances is a common public health problem all over the world. As these substances generate euphoria frequency of use among adolescents and young adults is increasing steadily. In cases using inhalants to achieve a euphoric state -without knowing possible consequences- sudden death may occurdue to acute cardio-pulmonary dysfunction.Here we present a case of sudden death of a nineteen-year-old female due to inhalation of volatile from butane containing lighter gas tube, with the findings of autopsy and death scene investigation.In the context of this case; it was aimed to draw attention to the risk of sudden death and steady increase of frequencyof volatile substance abuse among adolescents and young adults due to various psycho-social factors.

  10. Sudden and unexpected death from pituitary tumor apoplexy.

    Science.gov (United States)

    Shields, Lisa B E; Balko, M Gregory; Hunsaker, John C

    2012-01-01

    Pituitary tumor apoplexy refers to a clinical syndrome precipitated by the expansion of a pituitary adenoma by hemorrhage or infarction. Individuals may present with myriad signs, including sudden onset of severe headache, visual changes, altered mental status, cranial nerve palsies, and hormonal dysfunction. This disorder constitutes a medical emergency and warrants an expedited evaluation, diagnosis, and treatment to prevent the potential sequelae of permanent visual loss, endocrine abnormalities, or death. We report a case of sudden death from undiagnosed pituitary tumor apoplexy. The decedent was evaluated by medical personnel on three occasions in the week prior to her death for severe headache, nausea, vomiting, and photophobia. Postmortem examination demonstrated a hemorrhagic infarction of a pituitary adenoma with necrosis and expansion out of the sella turcica. The recognition of and treatment for a patient with pituitary tumor apoplexy requires a rapid multidisciplinary effort. Failure of prompt diagnosis may be fatal and require a medico-legal death investigation for sudden and unexpected death.

  11. MANAGEMENT OF IDIOPATHIC SUDDEN SENSORINEURAL HEARING LOSS: OUR EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Surya Prakash

    2015-12-01

    Full Text Available Sudden Sensorineural Hearing Loss (SSHL is dreaded condition affecting many individuals around the world due to its sudden appearance and inconspicuous nature of disease. More than 50% recover spontaneously, but timely identification of cause and treatment can help the patient immensely. METHODS In our study, we prospectively analyzed twenty patients presenting with idiopathic sudden hearing loss of 30 db or more between 2010 and 2015. RESULTS Two out of 20 patients (60% showed complete improvement and 10 patients out of 13 (77% who presented with 7 days showed complete recovery. Hence, time of presentation and drugs used directly affect the outcome of the patient. CONCLUSION It can be safely concluded that early diagnosis and management is key in treatment of SSHL. Intratympanic dexamethasone with intravenous dexamethasone or oral deflazacort is used in all patients with supportive measures has helped most of our patients. Oral acyclovir was used in only one patient.

  12. Cardiac hypertrophy: a risk factor for QT-prolongation and cardiac sudden death.

    Science.gov (United States)

    Kang, Y James

    2006-01-01

    Cardiac hypertrophy was viewed as a compensatory response to hemodynamic stress. However, cumulative evidence obtained from studies using more advanced technologies in human patients and animal models suggests that cardiac hypertrophy is a maladaptive process of the heart in response to intrinsic and extrinsic stimuli. Although hypertrophy can normalize wall tension, it is a risk factor for QT-prolongation and cardiac sudden death. Studies using molecular biology techniques such as transgenic and knockout mice have revealed many important molecules that are involved in the development of heart hypertrophy and have demonstrated signaling pathways leading to the pathogenesis. With the same approach, the consequence of heart hypertrophy has been examined. The significance of hypertrophy in the development of overt heart failure has been demonstrated and several critical molecular pathways involved in the process were revealed. A comprehensive understanding of the threats of heart hypertrophy to patients has helped to develop novel treatment strategies. The recognition of hypertrophy as a major risk factor for QT-prolongation and cardiac sudden death is an important advance in cardiac medicine. Cellular and molecular mechanisms of this risk aspect are currently under extensively exploring. These studies would lead to more comprehensive approaches to prevention of potential life threatening arrhythmia and cardiac sudden death. The adaptation of new approaches such as functional genomics and proteomics will further advance our knowledge of heart hypertrophy.

  13. Sudden death related to advanced coronary atherosclerosis in mini-pigs. Influence of some drugs

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsson, L.; Lundholm, L.; Wingren, G. (Department of Pharmacology, Linkoeping University, Linkoeping, Sweden)

    1984-01-01

    Advanced coronary atherosclerosis was produced in 30 mini-pigs by a combination of a hypercholesterolaemic diet and X-irradiation to the precordial region. Within 11-25 weeks after the irradiation, 13 of the 30 animals died a sudden death probably caused by coronary atherosclerosis. The contents of free and ester-bound cholesterol in the right coronary artery were significantly higher in the animals which died spontaneously than in surviving animals. In an untreated group of 12 animals 7 died whereas in a group treated with ..beta..-pyridylcarbinol only 1 out of 5 died. In the coronary arteries, the contents of both free and ester-bound cholesterol were significantly lower in the ..beta..-pyridylcarbinol-treated animals. In a sulfinpyrazontreated group 3 out of 8, and in a metoprolol-treated group 2 out of 5 animals died. None of these drugs reduced the accumulation of cholesterol in the coronary arteries. The rate of sudden death was 26 +- 6% (P<0.05) lower in the combined group of treated animals than in the untreated ones. By regular ECG recordings, signs which could predict the fatal outcome of the experiment were looked for. Although depressed ST segments were present before death in a few animals, this was not a regular phenomenon. It is concluded that advanced coronary atherosclerosis in mini-pigs often leads to sudden death and that this animal model seems suitable for testing the potential therapeutic effects of drugs.

  14. Characteristics of pressure drop for singlephase and two-phase flow across sudden contraction in microtubes

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Single-phase and gas-liquid two-phase pressure drops caused by a sudden con-traction in microtubes were experimentally investigated at room temperature and atmospheric pressure,using nitrogen and water. The experimental results on pressure drop with a novel measurement method,the tiny gaps on the tubes,were used to characterize the sudden contraction pressure drop for tube diameters from 850 to 330 μm. The ranges of the gas and liquid superficial velocity were 2.55―322.08 and 0.98―9.78 m/s in the smaller tube respectively. In single-phase flow experiments,the contraction loss coefficients were larger than the experimental results from conventional tubes in the laminar flow. While in the turbulent flow,the contraction loss coefficients were slightly smaller than those from conventional tubes and predicted well by Kc=0.5×(1-σ2)0.75. In two-phase flow experiments,the slip flow model with a velocity slip ratio S=(ρL/ρG)1/3 showed a good prediction that reveals the occurrence of velocity slip. An empirical correlation for two-phase flow pressure drops caused by the sudden contraction was developed based on the proposed contraction loss coefficients correlation for single-phase flow and Mar-tinelli factor.

  15. 突发灾害下医疗资源供应商选择模型及算法%Model and Algorithm of Medical Resources Supplier SelectionUnder Sudden-onset Disaster

    Institute of Scientific and Technical Information of China (English)

    刘天虎; 许维胜; 吴启迪

    2011-01-01

    This paper focuses on the modeling for supplier selection of medical resources, develops a multicriteria ranking method for supplier in which the information on the criteria's weights is incomplete and the criteria's value is interval intuitionistic fuzzy set The interval-valued intuitionistic fuzzy set of each supplier is aggregated through logical algorithms and the Hamming distance of each supplier is obtained. By using particle swarm optimization algorithms to solve the nonlinear programming models and the optional criteria weights are gained, and ranking is performed through the comparison of the distances between each supplier and superior/inferior supplier alternative. Eventually, a supplier selection example under mass emergency is provided to demonstrate the validity and feasibility of the model and algorithm.%对医疗资源供应商选择问题进行建模,提出一种权重系数信息不完全的多准则区间直觉模糊集的供应商排序算法.该算法通过逻辑集成得到各供应商的区间直觉模糊集,计算各供应商的区间直觉模糊数的Hamming距离,并利用粒子群优化算法求解建立的非线性优化模型,得出最优准则的权重系数.通过比较各供应商与优等及次等供应商的距离,进行最优排序.以大规模突发灾害事件下的供应商选择为案例,说明该模型及算法的有效性和可行性.

  16. The mechanisms of sudden-onset type adverse reactions to oseltamivir.

    Science.gov (United States)

    Hama, R; Bennett, C L

    2017-02-01

    Oseltamivir is contraindicated for people aged 10-19 in principle in Japan, due to concern about abnormal behaviours. Sudden death is another concern. This review examines growing evidence of their association and discusses underlying mechanisms of these sudden-onset type reactions to oseltamivir. First, the importance of animal models and the concept of human equivalent dose (HED) is summarized. Second, the specific condition for oseltamivir use, influenza infection, is reviewed. Third, findings from toxicity studies conducted prior to and after the marketing of oseltamivir are reported on to provide context on the observation of a possible causal association. Fourth, similarity and consistency of toxicity in humans with that in other animals is described. Finally, coherence of toxicokinetic and molecular level of evidence (channels, receptors and enzymes), including differences from the toxicity of other neuraminidase inhibitors, is reviewed. It is concluded that unchanged oseltamivir has various effects on the central nervous system (CNS) that may be related to clinical findings including hypothermia, abnormal behaviours including with fatal outcome, and sudden death. Among receptors and enzymes related to CNS action, it is known that oseltamivir inhibits nicotinic acetylcholine receptors, which are closely related to hypothermia, as well as human monoamine oxidase-A (MAO-A), which is closely related to abnormal or excitatory behaviours. Receptors such as GABAA , GABAB and NMDA and their related receptors/channels including Na(+) and Ca(2+) channels are thought to be other candidates for investigation related to respiratory suppression followed by sudden death and psychotic reactions (both acute and chronic), respectively.

  17. Neurocysticercosis causing sudden death:a case report

    Institute of Scientific and Technical Information of China (English)

    Martinez Fernanda; Seley Celeste; Marchesi Liliana; Fontanarossa Victoria; Rodriguez Dominique; Troncoso Alcides

    2010-01-01

    We report an acute case of a native man from Bolivia suffered from cephalalgia which rapidly worsened and ended in his sudden and unexpected death. Magnetic resonance imaging (MRI) of the brain was obtained. Features demonstrated on brainMRI scan were consistent with a diagnosis of neurocysticercosis (NCC). An autopsy showed the presence of intraventricular Taenia solium (T. solium) cysts which caused blockage of cerebrospinal fluid and secondary hydrocephalus. Due to the increasing travel movements of people neurocysticercosis must be considered as a cause of unexplained sudden death.

  18. [The significance of vestibular function assessment in sudden deafness].

    Science.gov (United States)

    Niu, Xiaorong; Zhang, Qing; Zhang, Rui

    2015-11-01

    Hearing loss caused by cochlear damage is the main symptom of sudden deafness (SD). Some patients also suffer from vestibular symptoms. In recent years, more attention has been paid to the vestibular dysfunction in patients with SD. The lesions could involve the whole inner ear in SD patients with and without vertigo. Comprehensive evaluation of vestibular function may help us understand the extent of lesions in sudden deafness and analyze the pathogenesis of disease. A less involvement of inner ear lesion may indicate a better hearing recovery.

  19. Uterine Arteriovenous Malformation with Sudden Heavy Vaginal Hemmorhage

    Directory of Open Access Journals (Sweden)

    Marianne Haughey

    2013-09-01

    Full Text Available Dysfunctional uterine bleeding (DUB is a common presentation in the emergency department and has a wide differential. Most presentations of DUB are in hemodynamically stable patients and can be evaluated as an outpatient. Uterine arteriovenous malformation (AVM is one presentation that can result in a life-threatening medical emergency with unexpected sudden and massive vaginal bleeding. We describe a case of a 24-year-old female with sudden heavy vaginal bleeding requiring a blood transfusion, ultrasound evidence of uterine AVM, and a treatment method of expectant management using an intrauterine device in an attempt to preserve fertility. [West J Emerg Med. 2013;14(5:411-414.

  20. Signs of illness preceding sudden unexpected death in infants.

    OpenAIRE

    Gilbert, R. E.; Fleming, P J; Azaz, Y; Rudd, P. T.

    1990-01-01

    OBJECTIVE--To determine whether signs of illness reported by parents can be used to identify babies at risk from the sudden infant death syndrome. DESIGN--A two year prospective case-controlled study based in a geographically defined area. SETTING--Four health districts in Avon and north Somerset. SUBJECTS--Babies who had died suddenly and unexpectedly aged between 1 week and 2 years (index babies) and two control babies for each index baby selected from the same health visitor's list and mat...

  1. Post-mortem toxicology in young sudden cardiac death victims

    DEFF Research Database (Denmark)

    Bjune, Thea; Risgaard, Bjarke; Kruckow, Line

    2017-01-01

    certificates and autopsy reports were retrieved and read to identify cases of sudden death and establish cause of death. All medico-legal autopsied SCD were included and toxicological reports collected. Positive toxicology was defined as the presence of any substance (licit and/or illicit). All toxicological...... findings had previously been evaluated not to have caused the death (i.e. lethal concentrations were excluded). We identified 620 medico-legal autopsied cases of SCD, of which 77% (n = 477) were toxicologically investigated post-mortem, and 57% (n = 270) had a positive toxicology profile. Sudden cardiac...

  2. Obesity paradox and risk of sudden death in heart failure results from the MUerte Subita en Insuficiencia cardiaca (MUSIC) study.

    Science.gov (United States)

    Gastelurrutia, Paloma; Pascual-Figal, Domingo; Vazquez, Rafael; Cygankiewicz, Iwona; Shamagian, Lillian Grigorian; Puig, Teresa; Ferrero, Andreu; Cinca, Juan; de Luna, Antoni Bayes; Bayes-Genis, Antoni

    2011-01-01

    among patients with heart failure (HF), body mass index (BMI) has been inversely associated with mortality, giving rise to the so-called obesity paradox. The aim of this study was to examine the relationship between BMI and two modes of cardiac death: pump failure death and sudden death. nine hundred seventy-nine patients with mild to moderate chronic symptomatic HF from the MUSIC (MUerte Subita en Insuficiencia Cardiaca) Study, a prospective, multicenter, and longitudinal study designed to assess risk predictors of cardiac mortality, were followed up during a median of 44 months. Independent predictors of death were identified by a multivariable Cox proportional hazards model. higher BMI emerged as an independent predictor of all-cause mortality (hazard ratio [HR] = 0.94, 95% confidence interval [CI] = 0.91-0.97, P = .0003) and pump failure death (HR = 0.93, 95% CI = 0.88-0.98, P = .004). Sudden death accounted for 45% of deaths in obese patients, 53% in overweight patients, and 37% in lean patients. No significant relationship between BMI and sudden death was observed (HR = 0.97, 95% CI = 0.92-1.02, P = .28). The only independent predictors of sudden death were prior history of myocardial infarction (HR = 1.89, 95% CI = 1.23-2.90, P = .004), hypertension (HR = 1.66, 95% CI = 1.05-2.63, P = .03), left ventricular ejection fraction (HR = 0.88, 95% CI = 0.79-0.96, P = .006), and N-terminal pro-B-type natriuretic peptide (HR = 1.01, 95% CI = 1.00-1.02, P = .048). the obesity paradox in HF affects all-cause mortality and pump failure death but not sudden death. The risk of dying suddenly was similar across BMI categories in this cohort of ambulatory patients with HF.

  3. 核电厂严重事故下卸压对氢气产生的影响分析%Effect of Depressurization on Hydrogen Generation During Severe Accident in PWR Nuclear Power Plant

    Institute of Scientific and Technical Information of China (English)

    陶俊; 李京喜; 佟立丽; 曹学武

    2011-01-01

    研究了1 000 MWe压水堆核电厂在典型的高压严重事故序列下卸压对氢气产生的影响.分析结果表明,开启1列、2列和3列卸压阀进行一回路卸压均会在堆芯熔化进程的3个阶段导致氢气产生率的明显增大:1)堆芯温度1 500~2 100 K;2)堆芯温度2 500~2 800 K;3)从形成由硬壳包容的熔融池(2 800 K)到熔融物向压力容器下封头下落.开启卸压阀的列数越多,氢气产生率的增大越明显.%The effect of depressurization on hydrogen generation during a typical high pressure severe accident sequence in a 1 000 MWe pressurized water reactor (PWR) nuclear power plant was analyzed. Analyses results indicate that the hydrogen generation rate is obviously increased by the reactor coolant system depressurization of opening one, two or three power operated relief valves (PORVs) at three core damage states.The first is peak core temperature from 1 500 K to 2 100 K. The second is peak core temperature from 2 500 K to 2 800 K. The third is from formation of molten pool supported by crust to slumping of molten materials into reactor pressure vessel lower head.The more PORVs are opened the more increment of hydrogen generation rate.

  4. Preventing tomorrow's sudden cardiac death today: dissemination of effective therapies for sudden cardiac death prevention.

    Science.gov (United States)

    Al-Khatib, Sana M; Sanders, Gillian D; Carlson, Mark; Cicic, Aida; Curtis, Anne; Fonarow, Gregg C; Groeneveld, Peter W; Hayes, David; Heidenreich, Paul; Mark, Daniel; Peterson, Eric; Prystowsky, Eric N; Sager, Philip; Salive, Marcel E; Thomas, Kevin; Yancy, Clyde W; Zareba, Wojciech; Zipes, Douglas

    2008-10-01

    Because the burden of sudden cardiac death (SCD) is substantial, it is important to use all guideline-driven therapies to prevent SCD. Among those therapies is the implantable cardioverter defibrillator (ICD). When indicated, ICD use is beneficial and cost-effective. Unfortunately, studies suggest that most patients who have indications for this therapy for primary or secondary prevention of SCD are not receiving it. To explore potential reasons for this underuse and to propose potential facilitators for ICD dissemination, the Duke Center for the Prevention of SCD at the Duke Clinical Research Institute (Durham, NC) organized a think tank meeting of experts on this issue. The meeting took place on December 12 and 13, 2007, and it included representatives of clinical cardiology, cardiac electrophysiology, general internal medicine, economics, health policy, the US Food and Drug Administration, the Centers for Medicare and Medicaid Services, the Agency for Health care Research and Quality, and the device and pharmaceutical industry. Although the meeting was funded by industry participants, this article summarizing the presentations and discussions that occurred at the meeting presents the expert opinion of the authors.

  5. Phosphodiesterase 4D gene polymorphisms in sudden sensorineural hearing loss.

    Science.gov (United States)

    Chien, Chen-Yu; Tai, Shu-Yu; Wang, Ling-Feng; Hsi, Edward; Chang, Ning-Chia; Wang, Hsun-Mo; Wu, Ming-Tsang; Ho, Kuen-Yao

    2016-09-01

    The phosphodiesterase 4D (PDE4D) gene has been reported as a risk gene for ischemic stroke. The vascular factors are between the hypothesized etiologies of sudden sensorineural hearing loss (SSNHL), and this genetic effect might be attributed for its role in SSNHL. We hypothesized that genetic variants of the PDE4D gene are associated with susceptibility to SSNHL. We conducted a case-control study with 362 SSNHL cases and 209 controls. Three single nucleotide polymorphisms (SNPs) were selected. The genotypes were determined using TaqMan technology. Hardy-Weinberg equilibrium (HWE) was tested for each SNP, and genetic effects were evaluated according to three inheritance modes. We carried out sex-specific analysis to analyze the overall data. All three SNPs were in HWE. When subjects were stratified by sex, the genetic effect was only evident in females but not in males. The TT genotype of rs702553 exhibited an adjusted odds ratio (OR) of 3.83 (95 % confidence interval = 1.46-11.18) (p = 0.006) in female SSNHL. The TT genotype of SNP rs702553 was associated with female SSNHL under the recessive model (p = 0.004, OR 3.70). In multivariate logistic regression analysis, TT genotype of rs702553 was significantly associated with female SSNHL (p = 0.0043, OR 3.70). These results suggest that PDE4D gene polymorphisms influence the susceptibility for the development of SSNHL in the southern Taiwanese female population.

  6. Sudden infant death syndrome (SIDS)--standardised investigations and classification

    DEFF Research Database (Denmark)

    Bajanowski, Thomas; Vege, Ashild; Byard, Roger W;

    2007-01-01

    criteria and inconsistent use of definitions. An approach to sudden infant death is outlined with discussion of appropriate tissue sampling, ancillary investigations and the use of controls in research projects. Standardisation of infant death investigations with the application of uniform definitions...

  7. Intratympanic corticosteroid for sudden hearing loss: does it really work?

    Science.gov (United States)

    Barreto, Monique Antunes de Souza Chelminski; Ledesma, Aleluia Lima Losno; de Oliveira, Carlos Augusto Costa Pires; Bahmad, Fayez

    2016-01-01

    Sudden deafness is characterized by an abrupt hearing loss of at least 30dB in three sequential frequencies in the standard pure tone audiogram over three days or less. Treatment is based on its etiology, and oral corticosteroids are widely used. Intratympanic corticosteroids are included as primary or secondary treatment when there is no improvement with the use of oral corticosteroids. To determine the effectiveness of therapy with intratympanic steroids in sudden deafness. A systematic review was performed of publications on the topic in the databases of PubMed/MEDLINE, with the keywords: sudden deafness, sudden hearing loss, and corticosteroids. Thirty scientific studies were analyzed. As to the objectives of the study analyzed, 76.7% sought to evaluate the use of intratympanic therapy salvage after failure to conventional treatment, and intratympanic therapy was used as the primary treatment 23.3% of the studies. Intratympanic corticosteroid therapy is prescribed primarily when there is failure of conventional therapy and when it is limited to use systemic corticosteroids, such as the diabetic patient. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  8. Left ventricular cardiac myxoma and sudden death in a dog

    NARCIS (Netherlands)

    de Nijs, M.I.|info:eu-repo/dai/nl/412015625; Vink, Aryan; Bergmann, W.|info:eu-repo/dai/nl/36275585X; Szatmári, V.|info:eu-repo/dai/nl/272734497

    2016-01-01

    Background: Myxoma is a very rare benign cardiac tumor in dogs. This is the first description of a cardiac myxoma originating from the left ventricular outflow tract, presumably causing sudden death. Case presentation: A previously healthy 12-year-old male West Highland white terrier was found dead

  9. Left ventricular cardiac myxoma and sudden death in a dog

    NARCIS (Netherlands)

    de Nijs, Maria Irene; Vink, Aryan; Bergmann, Wilhelmina; Szatmári, Viktor

    2016-01-01

    BACKGROUND: Myxoma is a very rare benign cardiac tumor in dogs. This is the first description of a cardiac myxoma originating from the left ventricular outflow tract, presumably causing sudden death. CASE PRESENTATION: A previously healthy 12-year-old male West Highland white terrier was found dead

  10. Sudden unilateral deafness with endolymphatic sac adenocarcinoma: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Gaeta, M.; Blandino, A.; Minutoli, F.; Pandolfo, I. [Inst. of Radiological Sciences, Univ. of Messina (Italy)

    1999-10-01

    A 30-year-old man presented with sudden left deafness and vertigo. CT showed an osteolytic retrolabyrinthine tumour of the left temporal bone. High signal from the tumour and labyrinth was seen on fat-suppressed T 1-weighted images. At surgery, a haemorrhagic papillary-cystic adenocarcinoma of the endolymphatic sac was found. (orig.)

  11. Medicolegal Approach to Sudden Unexpected Death in Epileptic Patients

    Directory of Open Access Journals (Sweden)

    Erdal Özer

    2004-12-01

    Full Text Available Sudden unexpected death in epilepsy (SUDEP is defined as sudden, unexpected, witnessed or unwitnessed, non-traumatic and non-drowning death in patients with epilepsy, with or without evidence for a seizure and excluding documented status epilepticus, in which post-mortem examination does not reveal a toxicological or anatomical cause for death. SUDEP has long been recognised although excess mortality in epilepsy has not always been accepted. In the 1960’s it was suggested that there is no reason why an epileptic should not live as long as one who did not have epilepsy. SUDEP’s occurrence is still not widely recognised and epidemiological studies to evaluate risk factors are fraught with problems. It has been estimated that the risk of sudden death for someone with epilepsy is almost 24 times higher than for someone without epilepsy. Although SUDEP has been reported since the turn of the century, the incidence and pathophysiology of this phenomenon are not well understood. The incidence of SUDEP, possible mechanisms involved, potential risk factors and current research strategies are reviewed and examined with a perspective of forensic science practice in our country. Key Words: Epilepsy, sudden unexpected death, forensic medicine.

  12. Sudden oak death effects on the dynamics of dead wood

    Science.gov (United States)

    Richard C. Cobb; Jo& atilde; o Filipe A.N.; Margaret R. Metz; Ross K. Meentemeyer; David M. Rizzo

    2013-01-01

    Sudden oak death has impacted forests notable for high-fire risk and contiguous host communities in California and Oregon coastal forest ecosystems. The disease continues to emerge in stands and landscapes with a large biomass of tanoak (Notholithocarpus densiflorus (Hook.&Arn.) Manos, Cannon & S.H.Oh), and we show that woody debris also...

  13. Sudden sensorineural hearing loss posthypothyroidism: A case study

    Directory of Open Access Journals (Sweden)

    Priya Karimuddanahally Premkumar

    2016-01-01

    Full Text Available Sudden sensorineural hearing loss is defined as a loss of at least 30 dB in three contiguous frequencies over a period of three days or less. In the present study a client with sudden hearing loss post hypothyroidism is discussed. A 56 year old client reported of awakening from sleep due to ear fullness along with severe tinnitus and experienced reduced hearing sensitivity in the right ear. The client had a history of hypothyroidism and was under medication for the same. The successive audiological investigations revealed that there was no improvement from prescribed medications, even with early identification and intervention. For better treatment outcomes correct identification of the cause as well as application of cause based treatment procedure is essential. Endocrine disorder is said to be one of the causes for sudden sensorineural hearing loss and one among this disorder is hypothyroidism. The present study aimed to throw a light on this aspect by giving a detailed case report of the client who suffered sudden sensorineural hearing loss which is suspected to be a long term effect of hypothyroidism.

  14. Study on Pulmonary Surfactant of Sudden Death of Infant

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To find the pathogenesis of sudden infant death syndrome (S IDS) from changes of pulmonurry surfactant. Methods By means of thin-layer ckromatography technique, surfactant in whole lung specimens of 10 infants with SIDS and 10 control infants without SIDS (dead of nonrespiratory diseases ) were examined qualitatively and quantitatively. Results Eleven components in pulmonary surfactant were examined qualitatively, including lysophosphatidylcholine , sphingomyelin , phosphatidylcholine , phosphatidylserine , phosphatidylinositol , phos phatidylethanolamine , phosphatidylglycerol , diphosphatidylylycerol , phosphatidic acid, cholesterol and neutral lipids. Quantitative examination showed that the amount of surfactant of whole lung specimens in sudden death group [-(8.9±1.0) rng/g wet lung weight] was significantly less than that in control group [-(12. 6±1.4) mg/g uet lung weight, P<0. 01]. Qualitative variance showed that the percentages of phosphatidylcholine (49. 4 % ± 2. 0 % ) and phosphatidylylycerol ( 2. 6 % ± 0. 7 % ) decreased markedly in sudden death group compared with those in control group (61.5 % ± 3. 0 % and 4.3 % ±1. 5%, P < 0. 01 ). Conclusion Before death there is serions defect on metabolism of pulmonary surfactant in sudden death infants, with the amount decreasing and the ratio of its components being disturbed, which is one of the important pathogenies of SIDS.

  15. Intratympanic corticosteroid for sudden hearing loss: does it really work?

    Directory of Open Access Journals (Sweden)

    Monique Antunes de Souza Chelminski Barreto

    Full Text Available ABSTRACT INTRODUCTION: Sudden deafness is characterized by an abrupt hearing loss of at least 30 dB in three sequential frequencies in the standard pure tone audiogram over three days or less. Treatment is based on its etiology, and oral corticosteroids are widely used. Intratympanic corticosteroids are included as primary or secondary treatment when there is no improvement with the use of oral corticosteroids. OBJECTIVE: To determine the effectiveness of therapy with intratympanic steroids in sudden deafness. METHODS: A systematic review was performed of publications on the topic in the databases of PubMed/MEDLINE, with the keywords: sudden deafness, sudden hearing loss, and corticosteroids. RESULTS: Thirty scientific studies were analyzed. As to the objectives of the study analyzed, 76.7% sought to evaluate the use of intratympanic therapy salvage after failure to conventional treatment, and intratympanic therapy was used as the primary treatment 23.3% of the studies. CONCLUSION: Intratympanic corticosteroid therapy is prescribed primarily when there is failure of conventional therapy and when it is limited to use systemic corticosteroids, such as the diabetic patient.

  16. Prognostic factors of profound idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Wen, Yu-Hsuan; Chen, Peir-Rong; Wu, Hung-Pin

    2014-06-01

    Profound idiopathic sudden sensorineural hearing loss is thought to have a poor prognosis, but few studies have focused on this condition. We aimed to assess the impact of patient factors, audiologic parameters, and salvage intratympanic steroid injection therapy on the prognosis of profound idiopathic sudden sensorineural hearing loss. The demographic, clinical, and audiologic data, degree of hearing recovery, and efficacy of intratympanic steroid injection therapy in 576 patients with profound idiopathic sudden sensorineural hearing loss (mean age 56.2 ± 14.9 years) who had been admitted at four tertiary referral centers between 2000 and 2011 were retrospectively reviewed. The mean hearing level at the initial presentation was 108.1 ± 9.5 dB. Many patients experienced vertigo (52.1%) and tinnitus (77.4%). At the 2-month follow-up, 172 (29.8%) patients showed some degree of hearing recovery, but only 21 (3.6%) patients recovered normal hearing. Further, the 116 patients who had received salvage intratympanic steroid injections showed a better audiologic outcome (improvement, 26.1 ± 24.3 vs. 15.7 ± 22.1 dB; P = 0.000) than those who had not (n = 429). In conclusion, a higher degree of hearing loss at the initial presentation indicates a poorer prognosis. Salvage intratympanic steroid injection therapy may improve the hearing of patients with profound idiopathic sudden sensorineural hearing loss after the failure of systemic steroid therapy.

  17. Sudden cardiac death in Nigerians - The Ile - Ife experience

    African Journals Online (AJOL)

    Keywords: Sudden cardiac death, Hypertensive heart disease, .... ge lllijsgrinswe ar mmyopalhles C CHD VI IE mitral valve leaflets were fused and de-. Diseases formed with ... 51 ' 60 13 5 " 1 1 ' 1 “ with fibrosis of the endocardium. The cause.

  18. Bidirectional infrasonic ducts associated with sudden stratospheric warming events

    NARCIS (Netherlands)

    Assink, J.D.; Waxler, R.; Smets, P.S.M.; Evers, L.G.

    2014-01-01

    In January 2011, the state of the polar vortex in the midlatitudes changed significantly due to a minor sudden stratospheric warming event. As a result, a bidirectional duct for infrasound propagation developed in the middle atmosphere that persisted for 2 weeks. The ducts were due to two zonal wind

  19. Sudden death due to swimming in elderly women.

    Science.gov (United States)

    Škavić, Petar; Duraković, Din

    2015-03-01

    The aim was to analyze the rate of sudden death in elderly Croatian women in comparison to elderly Croatian men, who died suddenly due to swimming. In the period from 2002 to 2011 one elderly Croatian woman and five elderly men died suddenly during swimming. In the same time, the same number of elderly foreigners died due to swimming at the Croatian Adriatic coast. One Croatian woman aged 66, who suffered of arterial hypertension with left ventricular hyper- trophy of 15 mm, diabetes mellitus and alcoholic liver cirrhosis, drowned in the sea during swimming. She was intoxi- cated with alcohol and had alcohol level in urine of 3.03 per thousand. One foreign woman, aged 82, who suffered coronary heart disease with left ventricular scar after myocardial infarction, arterial hypertension with excessive left ventricular hypertrophy of 22 mm and nephroangiosclerosis, suddenly lost conscionsness during swimming. The death rate in elderly Croatian women due to swimming reached 0.25, and the death rate in men is eight times higher: 1.97 (p = 0.0701), but the difference is not significant probably because of a small observational number.

  20. Monitoring of Sudden Ionospheric Disturbances (SID) from Kolkata (INDIA)

    CERN Document Server

    Chakrabarti, S K; Bose, B; Mandal, S; Chatterjee, A; Nandi, N M; Pal, S; Khan, R; Chakrabarti, Sandip K.

    2003-01-01

    We report our first results of monitoring sudden ionospheric disturbances (SID). We present data taken continuously for two weeks during 20th Sept. 2002 and 4th Oct. 2002. We compare the effects of solar flares of the VLF signal with those obtained by GOES Satellite of NASA monitoring in X-rays and found excellent agreement.

  1. Left ventricular cardiac myxoma and sudden death in a dog

    NARCIS (Netherlands)

    de Nijs, Maria Irene; Vink, Aryan; Bergmann, Wilhelmina; Szatmári, Viktor

    2016-01-01

    BACKGROUND: Myxoma is a very rare benign cardiac tumor in dogs. This is the first description of a cardiac myxoma originating from the left ventricular outflow tract, presumably causing sudden death. CASE PRESENTATION: A previously healthy 12-year-old male West Highland white terrier was found dead

  2. Left ventricular cardiac myxoma and sudden death in a dog

    NARCIS (Netherlands)

    de Nijs, M.I.; Vink, Aryan; Bergmann, W.; Szatmári, V.

    2016-01-01

    Background: Myxoma is a very rare benign cardiac tumor in dogs. This is the first description of a cardiac myxoma originating from the left ventricular outflow tract, presumably causing sudden death. Case presentation: A previously healthy 12-year-old male West Highland white terrier was found dead

  3. The fate of bound systems through Sudden Future Singularities

    CERN Document Server

    Perivolaropoulos, Leandros

    2016-01-01

    Sudden singularities occur in FRW spacetimes when the scale factor remains finite and different from zero while some of its derivatives diverge. After proper rescaling, the scale factor close to such a singularity at $t=0$ takes the form $a(t)=1+ c |t|^\\eta$ (where $c$ and $\\eta$ are parameters and $\\eta\\geq 0$). We investigate analytically and numerically the geodesics of free and gravitationally bound particles through such sudden singularities. We find that even though free particle geodesics go through sudden singularities for all $\\eta\\geq 0$, bound systems get dissociated for a wide range of the parameter $c$. For $\\eta 1$ (Sudden Future Singularities (SFS)) bound systems get a finite impulse that depends on the value of $c$ and get dissociated for values of $c$ larger than a critical value $c_{cr}(\\eta,\\omega_0)>0$ that increases with the value of $\\eta$ and the rescaled angular velocity $\\omega_0$ of the bound system. We obtain an approximate equation for the analytical estimate of $c_{cr}(\\eta,\\omeg...

  4. Study on Pulmonary Surfactant of Sudden Death of Infant

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To find the pathogenesis of sudden infant death syndrome (S IDS) from changes of pulmonurry surfactant. Methods By means of thin-layer ckromatography technique, surfactant in whole lung specimens of 10 infants with SIDS and 10 control infants without SIDS (dead of nonrespiratory diseases ) were examined qualitatively and quantitatively. Results Eleven components in pulmonary surfactant were examined qualitatively, including lysophosphatidylcholine , sphingomyelin , phosphatidylcholine , phosphatidylserine , phosphatidylinositol , phos phatidylethanolamine , phosphatidylglycerol , diphosphatidylylycerol , phosphatidic acid, cholesterol and neutral lipids. Quantitative examination showed that the amount of surfactant of whole lung specimens in sudden death group [-(8.9±1.0) rng/g wet lung weight] was significantly less than that in control group [-(12. 6±1.4) mg/g uet lung weight, P<0. 01]. Qualitative variance showed that the percentages of phosphatidylcholine (49. 4 % ± 2. 0 % ) and phosphatidylylycerol ( 2. 6 % ± 0. 7 % ) decreased markedly in sudden death group compared with those in control group (61.5 % ± 3. 0 % and 4.3 % ±1. 5%, P < 0. 01 ). Conclusion Before death there is serions defect on metabolism of pulmonary surfactant in sudden death infants, with the amount decreasing and the ratio of its components being disturbed, which is one of the important pathogenies of SIDS.

  5. Detection of sudden death syndrome using a multispectral imaging sensor

    Science.gov (United States)

    Sudden death syndrome (SDS), caused by the fungus Fusarium solani f. sp. glycines, is a widespread mid- to late-season disease with distinctive foliar symptoms. This paper reported the development of an image analysis based method to detect SDS using a multispectral image sensor. A hue, saturation a...

  6. Guidelines for autopsy investigation of sudden cardiac death

    DEFF Research Database (Denmark)

    Basso, Cristina; Aguilera, Beatriz; Banner, Jytte

    2017-01-01

    Although sudden cardiac death (SCD) is one of the most important modes of death in Western countries, pathologists and public health physicians have not given this problem the attention it deserves. New methods of preventing potentially fatal arrhythmias have been developed and the accurate diagn...

  7. Effect of vinpocetine on hemorheology of patients with sudden deafness

    Institute of Scientific and Technical Information of China (English)

    Cong Ma; Wen-Qiang Xu

    2016-01-01

    Objective:To discuss and investigate the effect of vinpocetine on hemorheology of patients with sudden deafness.Methods:A total of 68 patients with sudden deafness treated in our hospital during March 2011 to March 2014 were select for the clinical contrast. After the informed consent of patients themselves and their families, the patients were randomly divided into control group (salvia miltiorrhiza injection group) and observation group (vinpocetine group) with 34 cases of each group. After the treatments conducted in two groups, the blood viscosity and other hemorheology indexes of patients with sudden deafness between two groups before and after treatment were tested, and the obtained results were analyzed and compared.Results:The blood viscosity and other hemorheology indexes of patients in observation group at 3rd, 7th and 14th Day after treatment were significantly lower than those before treatment and those in control group. There were significant differences between above indexes (P<0.05).Conclusions:The effect of vinpocetine on hemorheology of patients with sudden deafness is relatively positive and has the positive clinical effect on the improvement of ear local microcirculation.

  8. Training Emergency Responders: Sudden Infant Death Syndrome. An Instructor's Manual.

    Science.gov (United States)

    Applied Science Associates, Inc., Reston, VA.

    This manual was developed to help instructors train police and emergency medical technicians, who often are the first persons to arrive at the scene of a death (first responders), to serve families who lose a child to Sudden Infant Death Syndrome (SIDS). The manual begins with an introduction that discusses the purpose of the training and…

  9. Sudden Infant Death Syndrome, FY 1983. Special Report to Congress.

    Science.gov (United States)

    National Inst. of Child Health and Human Development (NIH), Bethesda, MD.

    This report describes research programs focusing on the sudden infant death syndrome (SIDS) and indicates some presently available results. Specific attention is given to research on sleep apnea, respiratory control, and hypoxia, as well as to infectious disease processes and immunology. Findings of a large-scale multidisciplinary SIDS project are…

  10. Morbus Fahr--considerations on a case of sudden death.

    Science.gov (United States)

    Unkrig, S; Gullotta, F; Madea, B

    2011-01-30

    Up to now, Fahr's disease has not been established as a cause of sudden death. We present the case of a middle-aged woman with vast bilateral basal ganglia and cerebellar calcifications that led to the diagnosis of Fahr's syndrome and at the same time gave a clue for the fatal outcome. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Linking sudden oak death with spatial economic value transfer

    Science.gov (United States)

    Tom Holmes; Bill Smith

    2008-01-01

    Sudden oak death (caused by Phytophthora ramorum) is currently having a dramatic impact on the flow of ecosystem services provided by trees and forests in California. Timber species in California are not thought to be at risk of mortality from this pathogen and, consequently, economic impacts accrue to non-market values of trees such as aesthetics,...

  12. Comparison of sudden deafness in adults and children.

    Science.gov (United States)

    Na, Se Young; Kim, Myung Gu; Hong, Seok Min; Chung, Ji Hyun; Kang, Ho Min; Yeo, Seung Geun

    2014-09-01

    Although many studies have assessed sudden deafness in adults, sudden deafness has not been evaluated in children. We therefore evaluated the differences in sudden deafness between children and adults. We compared clinical manifestations, including gender, audiogram pattern of initial hearing loss, and recovery rate after treatment in 87 children and 707 adults diagnosed with sudden deafness from September 2003 and August 2012. There were no differences in sex, side, or audiogram between children and adults (P>0.05 each). Hearing recovery rates in children and adults were 72.4% and 70.6%, respectively (P>0.05). Both children and adults with mild hearing loss showed significantly greater hearing recovery rates than individuals with profound hearing loss (P<0.05 each). The percentage with initially mild and moderate hearing loss was higher in children than in adults, as were the recovery rates of children compared to adults with initially mild, moderate-severe, and profound hearing loss (P<0.05 each). In regard to final hearing outcome after treatment, a low percentage of children showed no improvement whereas a high percentage showed complete recovery; a higher percentage of children than of adults showed complete recovery (P<0.05). Recovery rate from profound hearing loss was significantly higher in children than in adults (60.0% vs. 45.4%, P<0.05). Degree of hearing loss, gender, side, and recovery rate were similar in children and adults, but the rate of complete recovery was higher in children.

  13. Hearing outcome of recurrent sudden deafness: ipsilateral versus contralateral types.

    Science.gov (United States)

    Kuo, Yen-Lin; Young, Yi-Ho

    2012-03-01

    Patients with recurrent sudden deafness demonstrating normal vestibular-evoked myogenic potentials (VEMPs) in the lesion ear of the second episode may indicate a good hearing outcome. This study retrospectively reviewed our experience of patients with recurrent sudden deafness during the past 20 years. Sixteen (1.4 %) of 1156 patients with sudden deafness were diagnosed as having a recurrent episode, including ipsilateral type in 7 and contralateral type in 9. All patients underwent an audiovestibular test battery and blood and MRI examinations. After 2000, nine patients underwent the VEMP test. In the ipsilateral type, the mean interval between two episodes was 2 ± 2 years, which did not differ significantly from 3 ± 3 years in the contralateral type. There were no significant differences in relation to age at onset of the second episode, inter-episode interval, gender, presence of vertigo, and abnormal caloric results. However, abnormal rate of VEMP test in the contralateral type (five of five patients) was significantly higher than that in the ipsilateral type (none of four patients). At the second episode, all four patients with normal VEMPs on the lesion ear had improved hearing, while four of five patients with absent or delayed VEMPs showed unchanged hearing. Altogether, the hearing improvement rate in both types of recurrent sudden deafness was 50%.

  14. [Part of the vertebral artery in patients with sudden deafness].

    Science.gov (United States)

    Song, Yisa; Lv, Fengquan; Cai, Huixiau; Wu, Hao

    2013-08-01

    To explore the characteristics of vertebral artery system in the patients with sudden deafness by using digital subtraction angiography (DSA). Thirty-four cases of sudden deafness with vertebrobasilar artery ischemia confirmed by the color doppler ultrasound were undergone DSA in both side. The characteristics of vertebral artery, basal artery and before-cerebellum artery were analysis before specific therapy. There is no related complication were occurred among 34 cases. Side vertebral artery was blocked in 2 cases, atherosclerosis was found in 5 cases. The right cerebellar artery anterior and the left cerebellar artery posterior were found filling defect or minor change in 29.4% (10/34) and 35.3% (12/34) of the patients, respectively. The right and the left arteria auditiva interna were found filling defect or minor change in 64.7% (22/34) and 73.5% (25/34) of the patients, respectively. After specific therapy, 8 cases were cured, the hearing of 9 cases were markedly improved, the hearing of 12 cases were improved efficient and 5 patients have no hearing improvement, the total effective rate was 85.3%. The arteria auditiva interna and inferior anterior arteria cerebelli caused inner ear ischemia were found in the patients with sudden deafness. The using of vasodilator may have satisfactory and positive curative effect in the therapy of sudden deafness.

  15. Retrocochlear mass lesion in mid-frequency sudden deafness.

    Science.gov (United States)

    Lin, Yi-Tsen; Young, Yi-Ho

    2008-01-01

    This study retrospectively reviewed all cases of mid-frequency sudden deafness to understand the clinical significance of this hallmark finding. Retrospective study. From 1992 to 2006, a total of 556 patients with sudden deafness were experienced. Based on the audiographic configuration, these patients were classified into: flat-type group, 272 cases; high-frequency group, 146 cases; low-frequency group, 70 cases; mid-frequency group, 30 cases; and unclassified group, 38 cases. All patients underwent a battery of audiovestibular function testing. Among 556 sudden deafness patients, 17 patients (3%) were proved to have a retrocochlear tumor, including mid-frequency group (10), high-frequency group (4), flat-type group (2), and low-frequency group (1). Thus, the mid-frequency group had significantly higher (33%) association with a retrocochlear tumor than other groups. One-third of the patients with mid-frequency sudden deafness harbor a true retrocochlear mass lesion; hence, MR imaging is mandatory in such cases.

  16. Measurement and simulation of the two-phase velocity correlation in sudden-expansion gas-particle flows

    Institute of Scientific and Technical Information of China (English)

    Li-Xing Zhou; Yang Liu; Yi Xu

    2011-01-01

    In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer(PDPA) and simulated the system behavior by using both a Reynolds-averaged Navier-Stokes(RANS)model and a large-eddy simulation(LES). The results of the measurements yield the axial and radial time-averaged velocities as well as the fluctuation velocities of gas and three particle-size groups(30μm,50μm,and 95μm) and the gasparticle velocity correlation for 30μm and 50μm particles.From the measurements,theoretical analysis,and simulation,it is found that the two-phase velocity correlation of sudden-expansion flows,like that of jet flows,is less than the gas and particle Reynolds stresses. What distinguishes the two-phase velocity correlations of sudden-expansion flow from those of jet and channel flows is the absence of a clear relationship between the two-phase velocity correlation and particle size in sudden-expansion flows. The measurements,theoretical analysis,and numerical simulation all lead to the above-stated conclusions. Quantitatively,the results of the LES are better than those of the RANS model.

  17. Equilibrium and Sudden Events in Chemical Evolution

    CERN Document Server

    Weinberg, David H; Freudenburg, Jenna

    2016-01-01

    We present new analytic solutions for one-zone (fully mixed) chemical evolution models and explore their implications. In contrast to existing analytic models, we incorporate a realistic delay time distribution for Type Ia supernovae (SNIa) and can therefore track the separate evolution of $\\alpha$-elements produced by core collapse supernovae (CCSNe) and iron peak elements synthesized in both CCSNe and SNIa. In generic cases, $\\alpha$ and iron abundances evolve to an equilibrium at which element production is balanced by metal consumption and gas dilution, instead of continuing to increase over time. The equilibrium absolute abundances depend principally on supernova yields and the outflow mass loading parameter $\\eta$, while the equilibrium abundance ratio [$\\alpha$/Fe] depends mainly on yields and secondarily on star formation history. A stellar population can be metal-poor either because it has not yet evolved to equilibrium or because high outflow efficiency makes the equilibrium abundance itself low. Sy...

  18. Copy number variations in three children with sudden infant death.

    Science.gov (United States)

    Toruner, G A; Kurvathi, R; Sugalski, R; Shulman, L; Twersky, S; Pearson, P G; Tozzi, R; Schwalb, M N; Wallerstein, R

    2009-07-01

    Sudden death of an infant is a devastating event that needs an explanation. When an explanation cannot be found, the case is labeled as sudden infant death syndrome or unclassified sudden infant death. The influence of genetic factors has been recognized for sudden infant death, but copy number variations (CNVs) as potential risk factors have not been evaluated yet. Twenty-seven families were enrolled in this study. The tissue specimens from deceased children were obtained and array-based comparative genomic hybridization (array-CGH) experiments were performed on the genomic DNA isolated from these specimens using Agilent Technologies Custom 4 x 44K arrays. Quantitative polymerase chain reaction experiments were performed to confirm the overlapping duplication and deletion region in two different cases. A de novo CNV is detected in 3 of 27 cases (11%). In case 1, an approximately 3-Mb (chr 8: 143,211,215-qter) duplication on 8q24.3-qter and a 4.4-Mb deletion on the 22q13.3-qter (chr 22: 45,047,068-qter) were detected. Subtelomeric chromosome analysis of the father and the surviving sibling of case 1 showed a balanced reciprocal translocation, 46,XY,t(8;22)(q24.3;q13.3). A 240-kb (chr 6: 26,139,810-26,380,787) duplication and a 1.9-Mb deletion (chr 6: 26,085,971-27,966,150) at chromosome 6p22 were found in cases 2 and 3, respectively. Array-CGH and conventional cytogenetic studies did not reveal the observed CNVs in the parents and the siblings of cases 2 and 3. The detected CNVs in cases 2 and 3 encompassed several genes including the major histone cluster genes. Array-CGH analysis may be beneficial during the investigations after sudden infant death.

  19. Sudden hearing loss: Our experience in treatment with vasoactive therapy

    Directory of Open Access Journals (Sweden)

    Živić Ljubica

    2008-01-01

    Full Text Available Introduction A specific title "sudden hearing loss" refers to illness which is characterized by a sudden, rapid sensoneural hearing loss mostly in one ear without obvious causes, accompanied with dizziness, and without vestibular symptomatology. It is defined as a hearing loss for more than 30 dB on 3 or more successive frequencies which appear in 72 hours. Objective The main goal of our paper was to estimate success of implementation of vasoactive method in patients with sudden hearing loss of senso-neural type in different ranges in hospital conditions. METHOD Our research covered 37 patients hospitalized because of a sudden hearing loss of sensoneural type in different ranges. Diagnosis, in all patients, was established by clinical ORL examination, audiology and vestibular examination. R including CT and MR, neurological, internist and laboratory examinations were used in order to exclude other aetiology. In monitored patients, we started treatment with vasoactive therapy, ampules of xanthinol nicotinate (one ampule of 2 ml, 300 mg or ampules of pentoxiphylline (one ampule of 5 ml, 100 mg in form of infusions with addition of vitamins with an everyday gradual increase of dosage up to 12 ampules of xanthinol nicotinate and up to 5 ampules of pentoxiphylline. Then we started with an everyday decrease of dosage down to the first one. Results After the complete curing protocol, we found out that in patients with light and medium senso-neural damages of hearing sense (23 or 62%, hearing recovery was complete. In patients with heavy damage of hearing (9 or 24%, partial success was evidenced. The most difficult cases, with complete hearing loss, heavy buzzing and vertiginous problem (5 or 14% responded to therapy, so buzzing and vertiginous problems disappeared but hearing was not improved. Conclusion Usage of vasoactive medicaments in hospital conditions in treatment of sudden hearing loss gives good results and it is the closest to aetiological

  20. The most common cause of sudden cardiac death in athletes

    Directory of Open Access Journals (Sweden)

    Topalović Nikola

    2016-01-01

    Full Text Available The positive impact of exercise on cardiovascular health is well known. Athletes, who are constantly physically active, are considered to be the healthiest members of our society. That is why their sudden death, during the training or competition, attracts the attention of the general public. Rarely, tragic events of sudden cardiac death (SCD are the reason for questioning if by many positive there are also negative impact of physical exercise. The first case of SCD is recorded as far back as the year 490 BC, when the Greek soldier Pheidippides died after he conveyed news of the great victory of the Greeks over the Persians. Risk of SCD is recognized in the middle of the twentieth century. In our region, discussion about this issue began after the World Basketball Championship, which was held in Ljubljana in 1970, because of the sudden death of the national team member Trajko Rajkovic. One of the important goals of modern sports medicine is to reduce the risk of SCD in athletes to 'inevitable rarity'. Definition of SCD is considered to be any unexpected death due to sudden cardiac arrest. Pedo (Pedoe has divided all causes of SCD in the sport into three categories: Commotio cordis (agitation of the heart, which results from blunt impact to the athletes chest with consequent fatal disorder of heart rhythm; SCD of athletes under the age of 35 because of structural, congenital and inflammatory heart disease, which includes hypertrophic cardiomyopathy as the most important cause of sudden cardiac death, congenital anomalies of the coronary arteries, arrhythmogenic right ventricular cardiomyopathy, myocarditis and other; SCD of athletes older than 35 years which is most common due coronary artery disease - atherosclerosis (the dominant risk in the marathon and half-marathon. .

  1. Effects of beta blockade on sudden cardiac death during acute myocardial infarction and the postinfarction period.

    Science.gov (United States)

    Hjalmarson, A

    1997-11-13

    About half of all deaths after myocardial infarction (MI) are sudden cardiac deaths. Most of these are thought to be due to ventricular fibrillation (VF). A number of interventions and many different antiarrhythmic agents have been investigated, but so far only beta-blocker therapy has been found to produce significant reductions in the risk of sudden cardiac death after MI. Reductions in total mortality and sudden cardiac death were first reported in 1981 in 3 placebo-controlled studies, the Norwegian Timolol Study, the American Beta-Blocker Heart Attack Trial (BHAT), and the Göteborg Metoprolol Trial. A few years later, two very large trials, the Metoprolol in Acute Myocardial Infarction (MIAMI) study and the First International Study of Infarct Survival (ISIS-1), which included 6,000 and 16,000 patients, respectively, showed that beta-blocker therapy could reduce mortality within the first 2 weeks after onset of MI. Data from 24 postinfarction studies with long-term follow-up show an average 20% mortality reduction over 2 years. Pooled results of 28 short-term, randomized, placebo-controlled trials in which beta blockers were given intravenously shortly after onset of MI indicate an average 13% mortality reduction within 2 weeks. In the 16 studies in which the sudden cardiac death rate was reported, the beneficial effect of beta blockade was even more marked: a 34% average reduction of risk. Not all studies with beta blockers, however, have demonstrated a significant reduction in the incidence of sudden cardiac death. Such an effect has been clearly demonstrated only for the more lipophilic beta blockers (timolol, metoprolol, and propranolol). Two of these lipophilic beta blockers, metoprolol and propranolol, have also been shown to prevent VF after MI in clinical studies. Based on observations from animal experiments, it has been proposed that beta blockers with a high degree of lipophilicity penetrate the brain and thereby maintain high vagal tone during

  2. 单光子和双光子Jaynes-Cummings模型中原子间纠缠突然死亡的研究%Study of Entanglement Sudden Death Between Two Atoms in the One-Photon and Two-Photon Jaynes-Cummings Models

    Institute of Scientific and Technical Information of China (English)

    廖庆洪; 刘晔; 贾书磊

    2012-01-01

    通过计算并发度和线性熵研究了单光子和双光子Jaynes-Cummings模型中两原子系统的纠缠随时间的演化特性,分析了原子初始纠缠度和不同腔场初态对并发度的影响.结果表明,当腔场初始处于|11>态时,两原子之间的纠缠出现突然死亡现象,纠缠死亡的持续时间依赖于原子初始纠缠度;并且发现两原子和腔场之间在整个时间演化过程中一直保持着纠缠状态.%The entanglement dynamics of two atoms in the one-photon and two-photon Jaynes-Cummings models are studied by employing the concurrence and linear entropy. The effect of the initial entanglement degree of two atoms and the initial state of the cavity field on the time evolution of concurrence is analyzed. The results show that the phenomenon of sudden death of entanglement between two atoms happens when the field is initially in the state (11). The length of the death time interval is dependent on the initial entanglement degree of two atoms. Moreover, it is found that the atom and the field are entangled in the overall time evolution process.

  3. Exploring sudden gains in behavioral activation therapy for Major Depressive Disorder.

    Science.gov (United States)

    Hunnicutt-Ferguson, Kallio; Hoxha, Denada; Gollan, Jackie

    2012-03-01

    Understanding the onset and course of sudden gains in treatment provides clinical information to the patient and clinician, and encourages clinicians to strive for these sudden clinical gains with their patients. This study characterizes the occurrence of sudden gains with Behavioral Activation (BA; Martell, Addis, & Jacobson, 2001), and the extent to which pre-treatment dysfunctional depressive thinking predicts sudden gains during treatment. We enrolled a sample of adults (n = 42) between ages 18-65 diagnosed with primary Major Depressive Disorder. All participants completed a 16-week course of BA, with clinical and self-report assessments at pre-, mid- and post-treatment. Results indicated that sudden gain and non-sudden gain participants showed differential improvement across treatment. No significant effects emerged for the dysfunctional cognitive style as a predictor of sudden gain status. Sudden gains may result from interaction of non-specific factors with the BA techniques implemented during early phases of therapy.

  4. Transient Response of Aerobic and Anoxic Activated Sludge Activities to Sudden Substrate Concentration Changes

    DEFF Research Database (Denmark)

    Sin, G.; Vanrolleghem, P.A.; Gernaey, Krist

    2004-01-01

    process. That transient phenomenon exhibits itself immediately upon addition of a substrate source to an endogenously respiring activated sludge sample and it usually takes a few minutes until the activated sludge reaches its maximum possible rate under given environmental conditions. This discrepancy......The state-of-the-art understanding of activated sludge processes as summarized in activated sludge models (ASMs) predicts an instantaneous increase in the biomass activity (which is measured, e.g., by the corresponding respiration rate OUR, NUR, etc.) under sudden substrate concentration changes...... with fast-alternating process conditions, although such studies are beyond the scope of this report. (C) 2004 Wiley Periodicals, Inc....

  5. Atomic entanglement sudden death in a strongly driven cavity QED system

    OpenAIRE

    Zhang, Ying-Jie; Man, Zhong-Xiao; Xia, Yun-Jie

    2008-01-01

    We study the entanglement dynamics of strongly driven atoms off-resonantly coupled with cavity fields. We consider conditions characterized not only by the atom-field coupling but also by the atom-field detuning. By studying two different models within the framework of cavity QED, we show that the so-called atomic entanglement sudden death (ESD) always occurs if the atom-field coupling lager than the atom-field detuning, and is independent of the type of initial atomic state.

  6. Stress-mediated Allee effects can cause the sudden collapse of honey bee colonies.

    Science.gov (United States)

    Booton, Ross D; Iwasa, Yoh; Marshall, James A R; Childs, Dylan Z

    2017-05-07

    The recent rapid decline in global honey bee populations could have significant implications for ecological systems, economics and food security. No single cause of honey bee collapse has yet to be identified, although pesticides, mites and other pathogens have all been shown to have a sublethal effect. We present a model of a functioning bee hive and introduce external stress to investigate the impact on the regulatory processes of recruitment to the forager class, social inhibition and the laying rate of the queen. The model predicts that constant density-dependent stress acting through an Allee effect on the hive can result in sudden catastrophic switches in dynamical behaviour and the eventual collapse of the hive. The model proposes that around a critical point the hive undergoes a saddle-node bifurcation, and that a small increase in model parameters can have irreversible consequences for the entire hive. We predict that increased stress levels can be counteracted by a higher laying rate of the queen, lower levels of forager recruitment or lower levels of natural mortality of foragers, and that increasing social inhibition can not maintain the colony under high levels of stress. We lay the theoretical foundation for sudden honey bee collapse in order to facilitate further experimental and theoretical consideration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Forecasting sudden changes in environmental pollution patterns

    Science.gov (United States)

    Olascoaga, María J.; Haller, George

    2012-01-01

    The lack of reliable forecasts for the spread of oceanic and atmospheric contamination hinders the effective protection of the ecosystem, society, and the economy from the fallouts of environmental disasters. The consequences can be dire, as evidenced by the Deepwater Horizon oil spill in the Gulf of Mexico in 2010. We present a methodology to predict major short-term changes in environmental contamination patterns, such as oil spills in the ocean and ash clouds in the atmosphere. Our approach is based on new mathematical results on the objective (frame-independent) identification of key material surfaces that drive tracer mixing in unsteady, finite-time flow data. Some of these material surfaces, known as Lagrangian coherent structures (LCSs), turn out to admit highly attracting cores that lead to inevitable material instabilities even under future uncertainties or unexpected perturbations to the observed flow. These LCS cores have the potential to forecast imminent shape changes in the contamination pattern, even before the instability builds up and brings large masses of water or air into motion. Exploiting this potential, the LCS-core analysis developed here provides a model-independent forecasting scheme that relies only on already observed or validated flow velocities at the time the prediction is made. We use this methodology to obtain high-precision forecasts of two major instabilities that occurred in the shape of the Deepwater Horizon oil spill. This is achieved using simulated surface currents preceding the prediction times and assuming that the oil behaves as a passive tracer. PMID:22411824

  8. Excess sudden cardiac deaths after short-term clarithromycin administration in the CLARICOR trial

    DEFF Research Database (Denmark)

    Winkel, Per; Hilden, J; Hansen, Jørgen Fischer;

    2011-01-01

    -hospital (nonsudden) death. Result: In 100 of 189 (53%) cardiovascular (CV) deaths in which it was possible to examine the question, there was a strong association between place of death and the classification of CV death as sudden or not-sudden. The excess mortality in the clarithromycin group was confined to sudden...

  9. Radiological quiz. Sudden sensorineural hearing loss due to multiple sclerosis.

    Science.gov (United States)

    Cabbarzade, Cavid; Özgen, Burçe; Sennaroglu, Levent

    2014-01-01

    A case with sudden sensorineural hearing loss (SSNHL) owing to multiple sclerosis (MS) who had clinical and dramatic radiological improvement just after medical therapy was reported in this article. Case report and review of related literature. A 22-year-old female patient with MS related SSNHL was presented in this article. Magnetic resonance imaging (MRI) revealed an MS plaque localized at pons extending from right cochlear nucleus to proximal part of the right cochlear nerve. Most dramatic recovery was present in the 5th day control MRI, where the plaque located on pons disappeared completely. On the 10th day control audiogram hearing recovery was observed and pure tone audiogram levels were almost normal. Sudden sensorineural hearing loss owing to MS is seen more common than expected. It has good prognosis. Magnetic resonance imaging is also thought to have an important role in diagnosis and treatment efficacy of SSNHL owing to MS. Published by Elsevier Urban & Partner Sp. z.o.o.

  10. Sudden sensorineural hearing loss in a multiple sclerosis case.

    Science.gov (United States)

    Tekin, Muhammet; Acar, Gul Ozbilen; Cam, Osman Halit; Hanege, Fatih Mehmet

    2014-01-01

    Multiple sclerosis (MS) is the most common demyelinating disease of the central nervous system. MS involves different regions of the central nervous system in different periods, and causes demyelination. MS is a neuromotor disorder which progresses with remissions and relapses. Symptoms of MS may regress completely or heal after the relapses leaving sequelae. Sudden sensorinerural hearing loss (SSHL) is hearing loss of 30 dB or more over at least three contiguous audiometric frequencies that develops over a period of a few hours to 3 days. In 4-10 % of the MS patients, sensorineural hearing loss occurs between relapses or remissions. In this case, audiotory brainstem response (ABR) test is the most appropriate test for the diagnosis of sensorineural hearing loss in MS patients. In this article, we will discuss a patient diagnosed as MS who presented with sudden sensorineural hearing loss during the remission of the disease.

  11. The Study on Pipe Sudden Enlargement Local Resistant Coefficient

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    During the design of pipeline,the determination of local resistant coefficient is often come arcoss. The sudden enlargement local resistant coefficient ζ1 = [1A1-A2]2 is determined through theory. In the paper,the sudden enlargement local resistant coefficient under the conditions of three kinds of A1-A2 was studied in experi-ment. In the end ,the result shows that ζ1 is related not only to two flow cross sections ,but also to the veloci research ,the relationship between ζ1A1-A2 and V1 was determined. In a word ,the hy-draulic calculation of pipeline can be done by taking correspondent ζ1 ,according to the design velocity V1 and A1/A2.

  12. Sudden unexpected death in epilepsy: Identifying risk and preventing mortality.

    Science.gov (United States)

    Lhatoo, Samden; Noebels, Jeffrey; Whittemore, Vicky

    2015-11-01

    Premature death among individuals with epilepsy is higher than in the general population, and sudden unexpected death is the most common cause of this mortality. A new multisite collaborative research consortium, the Center for sudden unexpected death in epilepsy (SUDEP) Research (CSR), has received major funding from the National Institutes of Health (NIH) to examine the possible biologic mechanisms underlying this potentially preventable comorbidity and develop predictive biomarkers for interventions that could lower SUDEP incidence. This inaugural report describes the structure of the CSR, its priorities for human and experimental research, and the strategic collaborations and advanced tools under development to reduce this catastrophic outcome of epilepsy. The CSR Partners Program will work closely with committed volunteer agencies, industry, and academic institutions to accelerate and communicate these advances to the professional and lay community.

  13. [Sudden cardiac death in individuals with normal hearts: an update].

    Science.gov (United States)

    González-Melchor, Laila; Villarreal-Molina, Teresa; Iturralde-Torres, Pedro; Medeiros-Domingo, Argelia

    2014-01-01

    Sudden death (SD) is a tragic event and a world-wide health problem. Every year, near 4-5 million people experience SD. SD is defined as the death occurred in 1h after the onset of symptoms in a person without previous signs of fatality. It can be named "recovered SD" when the case received medical attention, cardiac reanimation effective defibrillation or both, surviving the fatal arrhythmia. Cardiac channelopathies are a group of diseases characterized by abnormal ion channel function due to genetic mutations in ion channel genes, providing increased susceptibility to develop cardiac arrhythmias and SD. Usually the death occurs before 40 years of age and in the autopsy the heart is normal. In this review we discuss the main cardiac channelopathies involved in sudden cardiac death along with current management of cases and family members that have experienced such tragic event.

  14. Hyperbaric oxygen therapy for idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Murphy-Lavoie, H; Piper, S; Moon, R E; Legros, T

    2012-01-01

    Idiopathic sudden sensorineural hearing loss (ISSHL) is the newest indication approved by the Undersea and Hyperbaric Medical Society's Hyperbaric Oxygen Therapy Committee. Idiopathic sudden sensorineural hearing loss appears to be characterized by hypoxia in the perilymph and therefore the scala tympani and the organ of Corti. A review of the literature reveals more than 100 publications evaluating the use of hyperbaric oxygen (HBO2) for the treatment of ISSHL, including eight randomized controlled trials. The best and most consistent results are obtained when HBO2 is initiated within two weeks of symptom onset and combined with corticosteroid treatment. The average hearing gain is 19.3 dB for moderate hearing loss and 37.7 dB for severe cases. This improvement brings hearing deficits from the moderate/severe range into the slight/no impairment range. This is a significant gain that can markedly improve a patient's quality of life, both clinically and functionally.

  15. Sudden cardiac death secondary to antidepressant and antipsychotic drugs.

    Science.gov (United States)

    Sicouri, Serge; Antzelevitch, Charles

    2008-03-01

    A number of antipsychotic and antidepressant drugs are known to increase the risk of ventricular arrhythmias and sudden cardiac death. Based largely on a concern over QT prolongation and the development of life-threatening arrhythmias, a number of antipsychotic drugs have been temporarily or permanently withdrawn from the market or their use restricted. Some antidepressants and antipsychotics have been linked to QT prolongation and the development of Torsade de pointes arrhythmias, whereas others have been associated with a Brugada syndrome phenotype and the development of polymorphic ventricular arrhythmias. This review examines the mechanisms and predisposing factors underlying the development of cardiac arrhythmias, and sudden cardiac death, associated with antidepressant and antipsychotic drugs in clinical use.

  16. Sudden infant death syndrome: an unrecognized killer in developing countries

    Directory of Open Access Journals (Sweden)

    Ndu IK

    2016-02-01

    Full Text Available Ikenna Kingsley Ndu Department of Paediatrics, Enugu State University Teaching Hospital, Enugu, Nigeria Abstract: Sudden infant death syndrome (SIDS is defined as the sudden unexpected death of an infant <1 year of age, with onset of the fatal episode apparently occurring during sleep, that remains unexplained after a thorough investigation including performance of a complete autopsy and review of the circumstances of death and the clinical history. SIDS contributes to infant mortality and resulted in ~15,000 deaths globally in 2013. Most of the risk factors of SIDS are common in developing countries; yet, there has been little interest in SIDS by researchers in Africa. This review looks at the extent of the attention given to SIDS in a developing country like Nigeria, and factors responsible for the scarce data concerning this significant cause of mortality. Keywords: SIDS, mortality, Nigeria

  17. Medico legal investigations into sudden sniffing deaths linked with trichloroethylene.

    Science.gov (United States)

    Da Broi, Ugo; Colatutto, Antonio; Sala, Pierguido; Desinan, Lorenzo

    2015-08-01

    Sudden deaths attributed to sniffing trichloroethylene are caused by the abuse of this solvent which produces pleasant inebriating effects with rapid dissipation. In the event of repeated cycles of inhalation, a dangerous and uncontrolled systemic accumulation of trichloroethylene may occur, followed by central nervous system depression, coma and lethal cardiorespiratory arrest. Sometimes death occurs outside the hospital environment, without medical intervention or witnesses and without specific necroscopic signs. Medico legal investigations into sudden sniffing deaths associated with trichloroethylene demand careful analysis of the death scene and related circumstances, a detailed understanding of the deceased's medical history and background of substance abuse and an accurate evaluation of all autopsy and laboratory data, with close cooperation between the judiciary, coroners and toxicologists.

  18. [Prognostic factors of sudden sensorineural hearing loss in children].

    Science.gov (United States)

    Li, Fengjiao; Xue, Xijun; Wang, Li; Yang, Fengbo; Wang, Hongyang; Guan, Jing; Du, Wan; Xiong, Wenping; Wu, Kaiwen; Wu, Mukun; Yin, Zifang; Lan, Lan; Wang, Dayong; Wang, Qiuju

    2015-11-01

    The aim of this retrospective study was to analyze the recovery rate of sudden sensorineural hearing loss in children, and explore the prognostic factors in order to guide the clinical diagnosis and treatment. A retrospective review was conducted for the prognosis of children with sudden sensorineural hearing loss during the past 5 years (from November 2010 to May 2015) in Chinese PLA General Hospital. This paper have a complete clinical data of 101 patients (113 ears)with sudden hearing loss, ranging from 0 to 18 years old Patients were divided into four groups according to hearing recovery and eight putative prognostic factors were analyzed. Among 101 patients (113 ears), the ratio of male and female was 60:53. Treatment was initiated from 1 to 183 days after disease onset, with an average of (18.5 ± 22.1) d. Bilateral and unilateral hearing loss were 24 ears and 89 ears, respectively. The proportion of mild hearing loss, moderate hearing loss, severe hearing loss and profound hearing loss were 7.1%, 6.2%, 23.9% and 62.8%, respectively. Vertigo and tinnitus occurred in 54.9% and 77.9% of the patients, respectively. After the treatment, the complete recovery rate was 9.7% and the overall recovery rate was 36.3%. The degree of hearing loss, earlier treatment onset, sex and bilateral involvement were significantly associated with hearing recovery (P Sudden sensorineural hearing loss in children was generally identified as severe and profound hearing loss, but after positive and timely treatment, it can be improved or even cured. The mild hearing loss, earlier treatment onset, unilateral hearing loss and female were positive prognostic factors. The concurrence of tinnitus or vertigo, the results of ABR and DPOAE had no significant influence on prognosis.

  19. Ocular Needling for Treatment of Sudden Deafness in 40 Cases

    Institute of Scientific and Technical Information of China (English)

    石晶; 郑振

    2004-01-01

    @@ Sudden deafness is a commonly encountered otological disease. The etiology and pathogenesis are still unknown, and therefore no ideal treatment is available. In clinical, the disease is treated to recover the cellular functions by improving the microcirculation of the inner ear and nourishing the nerves. To seek a more effective method, we conducted a trial with ocular needling in 40 patients from May 1998 to April 2000. The therapeutic results were satisfactory as reported in the following.

  20. Aetiology of sudden cardiac death in sport: a histopathologist's perspective.

    Science.gov (United States)

    Sheppard, Mary N

    2012-11-01

    In the UK, when a young person dies suddenly, the coroner is responsible for establishing the cause of death. They will ask a consultant pathologist to carry out an autopsy in order to ascertain when, where and how that person died. Once the cause of death is established and is due to natural causes, the coroner can issue a death certificate. Importantly, the coroner is not particularly interested in the cause of death as long as it is due to natural causes, which avoids the need for an inquest (a public hearing about the death). However, if no identifiable cause is established at the initial autopsy, the coroner can refer the heart to a cardiac pathologist, since the cause of death is usually due to heart disease in most cases. Consultant histopathologists are responsible for the analysis of human tissue from both living individuals and the dead in order to make a diagnosis of disease. With recent advancements in the management protocols for routine autopsy practice and assessment following the sudden death of a young individual, this review describes the role of the consultant histopathologist in the event of a sudden death of a young athletic individual, together with the older middle-aged 'weekend warrior' athlete. It provides concise mechanisms for the main causes of sudden cardiac death (including coronary artery disease, cardiomyopathies, valve abnormalities, major vessel ruptures and electrical conduction abnormalities) based on detailed autopsy data from our specialised cardiac pathology laboratory. Finally, the review will discuss the role of the histopathologist in the event of a 'negative' autopsy.

  1. Adjusting to a sudden “aging” of the lens

    OpenAIRE

    Tregillus, KEM; Werner., JS; Webster, MA

    2016-01-01

    Color perception is known to remain largely stable across the lifespan despite the pronounced changes in sensitivity from factors such as the progressive brunescence of the lens. However, the mechanisms and timescales controlling these compensatory adjustments are still poorly understood. In a series of experiments, we tracked adaptation in observers after introducing a sudden change in lens density by having observers wear glasses with yellow filters that approximated the average spectral tr...

  2. Munchausen Syndrome: A Case with Presenting Sudden Hearing Loss

    Directory of Open Access Journals (Sweden)

    Murat Ozturk

    2013-04-01

    Full Text Available Munchausen syndrome is a psychiatric disorder that patients direct professionals with plausible, feigned, factitious symptoms. It%u2019s uncommon in otolaryngology clinics. We present a patient, complaint with sudden hearing loss and vertigo, and who underwent additional medical and invasive treatment in this paper. Patients with Munchausen syndrome allow invasive medical care easily, and they can be very convincing. It has to be diagnosed and kept in mind because of avoiding from unnecessary treatment.

  3. Adult sudden death caused by aspiration of chewing gum.

    Science.gov (United States)

    Njau, S N

    2004-01-28

    A case of a fatal foreign material aspiration is presented in the following text. A 24-year-old white male died suddenly. A piece of chewing gum lodged in a pool of frothy fluid was revealed at autopsy. Microscopic examinations revealed atelectasia emphysema, eosinophilic exudate and empty spaces. Blood and urine samples were analyzed, for alcohol and drug use by fluorescence polarization immunoassay (FPIA) on an Abbott AXSYM system. No alcohol or other drugs were detected in blood or urine.

  4. Outcomes of Severe to Profound Idiopathic Sudden Sensorineural Hearing Loss

    OpenAIRE

    Jo, Si-Young; Lee, Sungsu; Eom, Tae-Ho; Jeun, Eun-Sun; Cho, Hyong-Ho; Cho, Yong-Beom

    2015-01-01

    Objectives While a severe to profound sudden sensorineural hearing loss (SSNHL) may cause serious disability in verbal communication, there have been little studies focusing on this high degree SSNHL. The present study was aimed to investigate the characteristics of hearing recovery in a high degree SSNHL (>70 dB). Methods Three hundred and two SSNHL patients were enrolled. For a long-term follow-up, 46 patients were evaluated. Hearing level was examined by pure tone audiometry on day 1, week...

  5. Idiopathic Sudden Sensorineural Hearing Loss With Minimal Hearing Impairment

    OpenAIRE

    Lee, Ho Yun; Cho, Chin Saeng

    2015-01-01

    Objectives The aim of the study was to determine the characteristics of patients who did not match the audiometric criteria of idiopathic sudden sensorineural hearing loss (SSNHL) but complained of acute hearing loss. Methods By thorough medical chart reviews, historical cohort study was performed with consecutive data of 589 patients complaining of acute unilateral sensorineural hearing loss without identifiable causes between 2005 and 2013. Those patients demonstrating a hearing loss of at ...

  6. Postmortem blood ferritin concentrations in sudden infant death syndrome.

    OpenAIRE

    Worwood, M; Raha-Chowdhury, R; Fagan, D G; Moore, C A

    1995-01-01

    AIMS--To confirm the observation of extremely high concentrations of ferritin in postmortem serum samples in sudden infant death syndrome (SIDS); to examine the factors influencing blood ferritin concentrations postmortem; to determine whether or not these high blood ferritin concentrations are characteristic of SIDS. METHODS--Postmortem samples of cardiac blood were obtained from 58 full term infants who died of SIDS and 14 full-term infants who died of a variety of other causes. Whole blood...

  7. Melatonin concentrations in the sudden infant death syndrome

    Science.gov (United States)

    Sturner, W. Q.; Lynch, H. J.; Deng, M. H.; Gleason, R. E.; Wurtman, R. J.

    1990-01-01

    The melatonin levels in various body fluids of the sudden infant death syndrome (SIDS) infants are compared with those of infants of comparable age who died of other causes to examine a possible relationship between pineal function and SIDS. After adjusting for age differences, cerebrospinal fluid melatonin levels are found to be significantly lower in the SIDS infants. It is suggested that diminished melatonin production may be characteristic of SIDS and could represent an impairment in the maturation of physiologic circadian organization.

  8. Genotyping of Clostridium perfringens associated with sudden death in cattle

    OpenAIRE

    2009-01-01

    Toxigenic types of Clostridium perfringens are significant causative agents of enteric disease in domestic animals, although type E is presumably rare, appearing as an uncommon cause of enterotoxemia of lambs, calves and rabbits. We report herein the typing of 23 C. perfringens strains, by the polymerase chain reaction (PCR) technique, isolated from small intestine samples of bovines that have died suddenly, after manifesting or not enteric or neurological disorders. Two strains (8.7%) were i...

  9. [Multicenter trial for sudden hearing loss therapy - planning and concept].

    Science.gov (United States)

    Plontke, S K; Girndt, M; Meisner, C; Probst, R; Oerlecke, I; Richter, M; Steighardt, J; Dreier, G; Weber, A; Baumann, I; Plößl, S; Löhler, J; Laszig, R; Werner, J A; Rahne, T

    2016-04-01

    Systemic steroids are widely used worldwide as a standard of care for primary therapy of idiopathic sudden sensorineural hearing loss (ISSHL). The German ISSHL guideline recommends high-dose steroids for primary therapy of ISSHL, without evidence from randomized controlled trials (RCTs). The rationale for the treatment of ISSHL using high dose steroids is only based on retrospective cohort studies.This article describes the planning and initiation of a multicenter, national, randomized, controlled clinical trial entitled Efficacy and safety of high dose glucocorticosteroid treatment for idiopathic sudden sensorineural hearing loss - a three-armed, randomized, triple-blind, multicenter trial (HODOKORT). This clinical trial aims to compare standard dose with two types of high-dose steroids for primary systemic therapy with respect to their efficacy in improving hearing, and thus communication ability, in patients with idiopathic sudden sensorineural hearing loss.This study is funded by the "Clinical Trials with High Patient Relevance" research program in the health research framework of the German Federal Ministry of Education and Research. It is one of two studies by the German Study Center of Clinical Trials of the German Society of Otorhinolaryngology, Head and Neck Surgery (DSZ-HNO). Planning and initiation was done in cooperation with the DSZ-HNO, the Coordination Center of Clinical Trials of the Martin-Luther-University Halle-Wittenberg, and the Study Center of the University Hospital Freiburg.

  10. [Aggravation after Diagnosis of Sudden Sensorineural Hearing Loss].

    Science.gov (United States)

    Fukumoto, Ichiro; Nemoto, Toshimitsu; Tsukuda, Tomoko; Koshizuka, Keiichi

    2015-03-01

    Among 95 patients with sudden sensorineural hearing loss who received inpatient treatment at our hospital within the 27-month period between October 2009 and December 2011, those in whom hearing loss was aggravated after diagnosis were compared with a control group. Hearing loss aggravation was defined as a decrease by 10 dB or more in the mean hearing threshold at 5 frequencies from 250 to 4,000 Hz or decrease of 15 dB or more in the hearing threshold at 2 consecutive frequencies. Hearing loss was aggravated after diagnosis in 22 (23.2%) of the 95 patients, showing a similar tendency to that previously reported. Although the grades of hearing loss in these patients were higher than those in 73 control group patients, according to the sudden hearing loss severity classification, their outcomes were favorable. The hearing loss aggravation group consisted of those with steroid-dependent hearing loss (6) and those who had undergone perilymphatic fistula repair (4), in addition to a large number of patients with idiopathic hearing loss, including suspicious perilymphatic fistula (10). When hearing loss becomes aggravated after the diagnosis of sudden sensorineural hearing loss, it may be important to determine the most appropriate approach in each case, such as a careful and gradual decrease in the adenocortical steroid dose and the consideration of perilymphatic fistula repair.

  11. Lipid Profile among Patients with Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Mohammed, Ali A Muttalib

    2014-12-01

    Associations between hearing and blood lipids have been the focus of scientific inquiry for more than 50 years. The aim of the present study is to evaluate the association between hyperlipidaemia among patients presented with sudden sensorineural hearing loss compared to normal controls. A case control study concerned with 22 patients presented with sudden sensorineural hearing loss who underwent lipid profile evaluation. The lipid profile of these patients was compared with corresponding results of 55 age matched persons (volunteers) with normal hearing. These patients were collected from the Out Patient Department of ENT at Al-Jamhory Teaching Hospital, Mosul/Iraq and private clinic of the author for the period from February 2011 to July 2013. The average age of patients was 44.7 years with a range of 26-65 years. The peak age incidence was in the 5(th) decade of life. The study included 11 male patients (50 %) and 11 females (50 %). Meanwhile, the average age of the control group was 41.7 years with 25 (45.5 %) males and 30 (54.5 %) females. Statistical analysis showed that there was significant difference between the means of lipid profile and blood sugar of the patients and the control group apart from HDL where there was no significant difference. In conclusion, hyperlipidemia seems to be significantly associated with the occurrence of sudden sensorineural hearing loss according to this study.

  12. Sudden cardiac death: the perspectives of Spanish survivors.

    Science.gov (United States)

    Palacios-Ceña, Domingo; Losa-Iglesias, Marta Elena; Salvadores-Fuentes, Paloma; Fernández-de-las-Peñas, Cesar

    2011-06-01

    Sudden cardiac death is an episode of sudden death from cardiac causes in previously healthy patients. The aim of this study was to investigate the life experiences of patients who were resuscitated successfully following a sudden cardiac death. Purposeful sampling was used to recruit the nine participants through the snowball technique. Unstructured interviews were carried out until data saturation was reached. The Giorgi method of analysis, which seeks to reduce the participant's experience to minimal thematic units, common thematic groups, and essential themes in order to describe it, was used. Four essential themes were found: "facing fear"; "the search for meaning"; "feeling death up close and personal"; and "loneliness and estrangement". Nurses must integrate the lifestyle changes of patients who survive a cardiac death in order to provide adequate care following hospital discharge. Patients should undertake follow-up programs in order to receive counseling from health professionals. As a result, the creation of interdisciplinary support groups and the implementation of follow-up programs after hospital discharge are fundamental. Survivors' experiences can inform the development of nursing programs and hospital follow-up services that address the survival of cardiac death. © 2011 Blackwell Publishing Asia Pty Ltd.

  13. Sudden cardiac death in children (1-18 years)

    DEFF Research Database (Denmark)

    Winkel, Bo Gregers; Risgaard, Bjarke; Sadjadieh, Golnaz

    2014-01-01

    AIMS: Hitherto, sudden cardiac death in children (SCDc)-defined as sudden cardiac death (SCD) in the 1-18 years old-has been incompletely described in the general population. Knowledge on incidence rates, causes of death and symptoms prior to death is sparse and has been affected by reporting...... and referral bias. METHODS AND RESULTS: In a nationwide setting all deaths in children aged 1-18 years in Denmark in 2000-06 were included. To chart causes of death and incidence rates, death certificates and autopsy reports were collected and read. By additional use of the extensive healthcare registries...... in Denmark, we were also able to investigate prior disease and symptoms. During the 7-year study period there was an average of 1.11 million persons aged 1-18 years. There were a total of 1504 deaths (214 deaths per year) from 7.78 million person-years. A total of 114 (7.5%) were sudden and unexpected...

  14. [Idiopathic sudden deafness: a report of 96 patients].

    Science.gov (United States)

    Gabanou, F; Bera, G; Vincent, C

    2012-01-01

    Evaluation of the management of idiopathic sudden deafness indicating the usefulness of biological assessments and the pronostic factors of hearing recovery. This is a retrospective study of 96 patients with idiopathic sudden deafness referred to a tertiary centre between 2005 and 2009 treated with corticosteroids intravenously at a daily dose of 1 mg/kg. Mean tonal thresholds were assessed (PTA = [500 Hz + 1000 Hz + 2000 Hz + 4000 Hz]/4). Each audiogram was classified as five classes according to its frequency profile. The hearing recovery is significant between D0-D5 and D5-M1 for the frequencies 0.5, 1 and 2 kHz. For 4 kHz, the recovery is significant between 0 and J5. There is no statistically significant correlation between the presence of associated signs (tinnitus, vertigo) and hearing recovery. Hearing recovery according to the five types of audiograms has the same evolution in the follow-up time but with audiograms type E (cophosis or subcophosis) often associated with an hyporeactivity at the videonystagmography. The presence of cardiovascular disease is a predictor of poor hearing recovery. The usefullness of systematic extensive blood tests is low. In sudden deafness, the maximum hearing recovery takes place in the month following the onset of symptoms. The predictors of poor hearing recovery are an initial mean threshold > 70 dB, the existence of an associated cardiovascular disease.

  15. [The evaluating time of curative effect on sudden deafness].

    Science.gov (United States)

    Liu, Yangyun; Jiang, Wen; Mao, Kunhua; Chen, Qiong

    2012-04-01

    To explore the best evaluating time of curative effect on sudden deafness so that the curative effect on sudden deafness can been evaluated more exactly and literally. Pure tone audiometries in 112 cases of sudden deafness were performed on the pretreatment day and on the third, seventh, fourteenth post-treatment day, and in the first, second, third, fourth post-treatment month. All of acoustical data were analyzed. The total effective rates were statistical different between the third, seventh post-treatment day and the fourteenth post-treatment day, the first, second, third, fourth post-treatment month. There were no statistical difference between the fourteenth post-treatment day and the first post-treatment month. There were statistical difference between the fourteenth post-treatment day and the second, third, fourth post-treatment month. The total effective rates were no statistical difference between the first and the second, third, fourth post-treatment month but it was fluctuated in the first post-treatment month. The total effective rates were no statistical difference between the second and the third, fourth post-treatment month and it was changeless on the second post-treatment month. From the curve of recruitment of hearing in different time, the curve of the total effective rates ascend from the third post-treatment day, then get to plateau from the second post-treatment month. If the cure rates, the efficiency rates, the effective rates in different time were analyzed, respectively, the hearing improvement ascend in first two weeks then. Hearing improvement get to plateau from fourteenth post-treatment day. (1) The evaluated results of curative effect to sudden deafness correlated vary in different time point post-treatment. (2) Prognosis can be predicted approximately 2 weeks after treatment. Patients who recover acoustic sensibility within 2 weeks have more significant improvement than the patients who hearing improvement after 2 weeks treatment

  16. Sudden cardiac death in non-dialysis chronic kidney disease patients.

    Science.gov (United States)

    Caravaca, Francisco; Chávez, Edgar; Alvarado, Raúl; García-Pino, Guadalupe; Luna, Enrique

    2016-01-01

    A relatively high proportion of deaths in dialysis patients occur suddenly and unexpectedly. The incidence of sudden cardiac death (SCD) in non-dialysis advanced chronic kidney disease (CKD) stages has been less well investigated. This study aims to determine the incidence and predictors of SCD in a cohort of 1078 patients with CKD not yet on dialysis. Prospective observational cohort study, which included patients with advanced CKD not yet on dialysis (stage 4-5). The association between baseline variables and SCD was assessed using Cox and competing-risk (Fine and Grey) regression models. Demographic, clinical information, medication use, and baseline biochemical parameters of potential interest were included as covariates. During the study period (median follow-up time 12 months), 210 patients died (19%), and SCD occurred in 34 cases (16% of total deaths). All-cause mortality and SCD incidence rates were 113 (95% CI: 99-128), and 18 (95% CI: 13-26) events per 1000 patients/year, respectively. By Cox regression analysis, covariates significantly associated with SCD were: Age, comorbidity index, and treatment with antiplatelet drugs. This latter covariate showed a beneficial effect over the development of SCD. By competing-risk regression, in which the competing event was non-sudden death from any cause, only age and comorbidity index remained significantly associated with SCD. SCD is relatively common in non-dialysis advanced CKD patients. SCD was closely related to age and comorbidity, and some indirect data from this study suggest that unrecognised or undertreated cardiovascular disease may predispose to a higher risk of SCD. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  17. Sudden water pollution accidents and reservoir emergency operations: impact analysis at Danjiangkou Reservoir.

    Science.gov (United States)

    Zheng, Hezhen; Lei, Xiaohui; Shang, Yizi; Duan, Yang; Kong, Lingzhong; Jiang, Yunzhong; Wang, Hao

    2017-05-03

    Danjiangkou Reservoir is the source reservoir of the Middle Route of the South-to-North Water Diversion Project (MRP). Any sudden water pollution accident in the reservoir would threaten the water supply of the MRP. We established a 3-D hydrodynamic and water quality model for the Danjiangkou Reservoir, and proposed scientific suggestions on the prevention and emergency management for sudden water pollution accidents based on simulated results. Simulations were performed on 20 hypothetical pollutant discharge locations and 3 assumed amounts, in order to model the effect of pollutant spreading under different reservoir operation types. The results showed that both the location and mass of pollution affected water quality; however, different reservoir operation types had little effect. Five joint regulation scenarios, which altered the hydrodynamic processes of water conveyance for the Danjiangkou and Taocha dams, were considered for controlling pollution dispersion. The results showed that the spread of a pollutant could be effectively controlled through the joint regulation of the two dams and that the collaborative operation of the Danjiangkou and Taocha dams is critical for ensuring the security of water quality along the MRP.

  18. Defining Sudden Infant Death and Sudden Intrauterine Unexpected Death Syndromes with Regard to Anatomo-Pathological Examination

    Science.gov (United States)

    Ottaviani, Giulia

    2016-01-01

    Crib death, or sudden infant death syndrome (SIDS), is the most frequent form of death in the first year of life, striking one baby in every 1,700–2,000. Yet, despite advances in maternal–infant care, sudden intrauterine unexplained/unexpected death syndrome (SIUDS) has a sixfold to eightfold greater incidence than that of SIDS. Frequent congenital abnormalities, likely morphological substrates for SIDS–SIUDS, were detected, mainly represented by alterations of the cardiac conduction system, such as accessory pathways and abnormal resorptive degeneration, and hypoplasia/agenesis of the vital brainstem structures. On the basis of these considerations, the new common definition of the SIDS–SIUDS complex is “The sudden death of a fetus after the 25th gestational week or infant under one year of age which is unexpected by history and remains unexplained after a thorough case investigation, including examination of the death scene, performance of a general autopsy and examination of the fetal adnexa”. Therefore, given that the general autopsy does not disclose any cause of death, a more in-depth histopathological analysis of the cardiac conduction system and autonomic nervous system by specialized pathologists is necessary. PMID:27709109

  19. Trunk response to sudden forward perturbations - effects of preload and sudden load magnitudes, posture and abdominal antagonistic activation.

    Science.gov (United States)

    Shahvarpour, Ali; Shirazi-Adl, Aboulfazl; Mecheri, Hakim; Larivière, Christian

    2014-06-01

    Unexpected loading of the spine is a risk factor for low back pain. The trunk neuromuscular and kinematics responses are likely influenced by the perturbation itself as well as initial trunk conditions. The effect of four parameters (preload, sudden load, initial trunk flexed posture, initial abdominal antagonistic activity) on trunk kinematics and back muscles reflex response were evaluated. Twelve asymptomatic subjects participated in sudden forward perturbation tests under six distinct conditions. Preload did not change the reflexive response of back muscles and the trunk displacement; while peak trunk velocity and acceleration as well as the relative load peak decreased. Sudden load increased reflex response of muscles, trunk kinematics and loading variables. When the trunk was initially flexed, back muscles latency was delayed, trunk velocity and acceleration increased; however, reflex amplitude and relative trunk displacement remained unchanged. Abdominal antagonistic preactivation increased reflexive response of muscles but kinematics variables were not affected. Preload, initial flexed posture and abdominal muscles preactivation increased back muscles preactivity. Both velocity and acceleration peaks of the trunk movement decreased with preload despite greater total load. In contrast, they increased in the initial flexed posture and to some extent when abdominal muscles were preactivated demonstrating the distinct effects of pre-perturbation variables on trunk kinematics and risk of injury. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. PHOX2B polyalanine repeat length is associated with sudden infant death syndrome and unclassified sudden infant death in the Dutch population

    NARCIS (Netherlands)

    G. Liebrechts-Akkerman (Germaine); F. Liu (Fan); O. Lao Grueso (Oscar); A.H.A.G. Ooms (Ariadne ); K. van Duijn (Kate); M. Vermeulen (Mark); V.W.V. Jaddoe (Vincent); A. Hofman (Albert); A.C. Engelberts (Adele); M.H. Kayser (Manfred)

    2014-01-01

    textabstractUnclassified sudden infant death (USID) is the sudden and unexpected death of an infant that remains unexplained after thorough case investigation including performance of a complete autopsy and review of the circumstances of death and the clinical history. When the infant is below 1 yea

  1. Coronary atherosclerosis in sudden cardiac death: An autopsy study

    Directory of Open Access Journals (Sweden)

    Sudha M

    2009-10-01

    Full Text Available Background: The incidence of ischemic heart disease (IHD has markedly increased in India over the past few years. Considering the variations in racial, dietary and lifestyle patterns in our population, it is essential to study the biology of coronary atherosclerosis in our patients. Vulnerable plaques have a large number of foam cells, extracellular lipid, thin fibrous caps and clusters of inflammatory cells and are more prone to rupture. These plaques are nourished by the microvessels arising from the vasa vasorum of the blood vessels and by lumen-derived microvessels through the fibrous cap. This autopsy study was designed to analyse the coronary arterial tree in cases of sudden cardiac death, classify coronary atherosclerotic plaques and to assess the factors contributing to vulnerability of the plaques including inflammation, calcification and microvascular density. Materials and Methods: Seven cases of sudden cardiac death were included in the study. The hearts were perfusion-fixed and the coronary arteries along with their main branches were dissected and studied. The location of the plaques, type of plaques, presence of inflammation and calcification were assessed. The cap thickness and microvessel density per 1000um 2 were assessed. The statistical significance was estimated. Results and Conclusions: Extensive high-grade coronary atherosclerotic disease was seen in all sudden cardiac death cases. Majority of the plaques were vulnerable. High-grade inflammation was seen in most of the vulnerable and ruptured plaques. All the ruptured plaques were uncalcified indicating that calcification probably stabilizes the plaques and protects against rupture. Increased microvessel density was noted in ruptured plaques compared to vulnerable plaques. However, it was not statistically significant.

  2. Sudden death of cardiac origin and psychotropic drugs

    Directory of Open Access Journals (Sweden)

    Quadiri eTimour

    2012-05-01

    Full Text Available Mortality rate is high in psychiatric patients versus general population. An important cause of this increased mortality is sudden cardiac death (SCD as a major side-effect of psychotropic drugs. These SCDs generally result from arrhythmias occurring when the posology is high and may attain a toxic threshold but also at dosages within therapeutic range, in the presence of risk factors. There are three kinds of risk factors: physiological (e.g.: low cardiac rate of sportsmen, physiopathological (e.g.: hepatic insufficiency, hypothyroidism and "therapeutic" (due to interactions between psychotropic drugs and other medicines. Association of pharmacological agents may increase the likelihood of SCDs either by i a pharmacokinetic mechanism (e.g.: increased torsadogenic potential of a psychotropic drug when its destruction and/or elimination are compromised or ii a pharmacodynamical mechanism (e.g.: mutual potentiation of proarrhythmic properties of two drugs. In addition, some psychotropic drugs may induce sudden death in cases of pre-existing congenital cardiopathies such as i congenital long QT syndrome, predisposing to torsade de pointes that eventually cause syncope and sudden death. ii a Brugada syndrome, that may directly cause ventricular fibrillation due to reduced sodium current through Nav1.5 channels. Moreover, psychotropic drugs may be a direct cause of cardiac lesions also leading to SCD. This is the case, for example, of phenothiazines responsible for ischemic coronaropathies and of clozapine that is involved in the occurrence of myocarditis. The aims of this work are to delineate: i the risk of SCD related to the use of psychotropic drugs; ii mechanisms involved in the occurrence of such SCD; iii preventive actions of psychotropic drugs side effects, on the basis of the knowledge of patient-specific risk factors, documented from clinical history, ionic balance and ECG investigation by the psychiatrist.

  3. Pathomorphological cardial changes in the sudden infant death syndrome

    Directory of Open Access Journals (Sweden)

    Rozumny D.V.

    2014-03-01

    Full Text Available In order to establish the relationship between the timing of fetal obliteration of communication and expression remodeling of the heart chambers, as one of the possible causative factors of SIDS, the selected material has been based on macromorphometric study. Material included 43 hearts from infants who died of SIDS. The control group consisted of 48 hearts of children suddenly dead from aspiration of gastric contents and infectious disease. The methods composed a macroscopic examination of the heart by the method of separate weighing of the complex morphometric studies, histological examination (used the following stains: hematoxylin and eosin, picrofuchsin by Van Gieson, Nissl's stain, immunohistochemical method using markers of neurofilament. The results revealed that in children who died of SIDS, obliteration of the fetal communication occurs essentially in the late period —to the age of 8 months, and the mass of the left and right ventricles of the heart exceeds the age limit of normal due to the prevalence of ventricular muscle mass and hypertrophy of cardiomyocytes. In all parts of the heart subendocardial fibrosis in the ventricles — pronounced interstitial fibrosis has been observed. In the interatrial septum at the location at the oval window morphometric study resulted in significant predominance area percentage of connective tissue in relation to the muscle tissue. On histological sections elements of the nervous tissue — randomly arranged nerve ganglia with degenerative changes and nerve fibers were identified. Conclusion. Finally, it should be noted that the growth of cardiosclerosis in all parts of the heart in newborns and infants, who died suddenly from SIDS, extends the terms of obliteration of fetal communications, and degenerative changes in the nerve ganglia that lead to the disturbance of supply and distribution of nerve impulses that pass through them. These factors contribute to the development of hemodynamic

  4. Sudden sensorineural hearing loss: Is there a connection with inner ear electrolytic disorders? A literature review.

    Science.gov (United States)

    Ciorba, Andrea; Corazzi, Virginia; Bianchini, Chiara; Aimoni, Claudia; Skarzynski, Henryk; Skarzynski, Piotr Henryk; Hatzopoulos, Stavros

    2016-12-01

    Electrolytic disorders of the inner ear represent a model that could be implicated in partially explaining the pathogenesis of sudden sensorineural hearing loss (SSNHL). Different types of electrolytes and different inner-ear loci are involved in cochlear homeostasis physiologically, to ensure the maintenance of an ion-balanced cochlear environment allowing a normal hair cell function. It has been hypothesized that a sudden loss of endocochlear potential, due to a rapid disruption of the inner ear fluid osmolality, could be responsible for a deterioration of the hearing function caused by damaged hair cells. The aim of this paper was to review the current literature and identify sources which might validate/fortify the hypothesis that inner ear electrolytic disorders have a role in the etiopathogenesis of SSNHL. The data in the literature underline the importance of ionic homeostasis in the inner ear, but they do not support a direct link between SSNHL and electrolyte disorders/imbalances. There is marginal evidence from otoacoustic emissions research that an indirect link might be present. © The Author(s) 2016.

  5. Sudden or Gradual Sound Onset Differentially Affects Audiogenic Seizure Severity in Developmentally Primed Rats

    Directory of Open Access Journals (Sweden)

    Mark Zrull

    2005-01-01

    Full Text Available In a rat model of reflex epilepsy, sound-induced or audiogenic seizures (AGS are initiated by and propagated though excessive activity of inferior colliculus neurons. Because more auditory system neurons respond to onset of sound rather than a continuing sound, we examined the effect of sudden (SO and gradual (GO onset intensity of seizure-triggering sound on AGS severity. Long-Evans rats were primed for AGS using loud sound when they were 18 days old and were tested for seizures using loud noise when 32 days old. SO and GO groups of 10 rats, matched for AGS severity, were then tested three times for AGS. Overall, rated seizure activity was 39% more severe in GO than SO rats (p<.05, and the duration of clonus for GO animals was 28% longer than for SO rats (p<.05. While latency to clonic seizures was 24% longer in GO than SO rats, this was an artifact of the sound gradually reaching AGS-inducing intensity for the GO group. Because sensory neurons respond to change, sudden onset sound may allow more adaptation of AGS-prone inferior colliculus neurons than a gradual onset seizure-inducing stimulus. Ramping to a maximum intensity sound may produce greater seizure severity due to a greater number of neurons remaining active.

  6. Sudden or gradual sound onset differentially effects audiogenic seizure severity in developmentally primed rats

    Directory of Open Access Journals (Sweden)

    Mary Dravland

    2005-08-01

    Full Text Available In a rat model of reflex epilepsy, sound-induced or audiogenic seizures (AGS are initiated by and propagated though excessive activity of inferior colliculus neurons. Because more auditory system neurons respond to onset of than a continuing sound, we examined the effect of sudden (SO and gradual (GO onset intensity of seizure-triggering sound on AGS severity. Long-Evans rats were primed for AGS using loud sound when they were 18 days old and were tested for seizures using loud noise when 32 days old. SO and GO groups of 10 rats, matched for AGS severity, were then tested 3 times for AGS. Overall, rated seizure activity was 39% more severe in GO than SO rats (p<.05, and the duration of clonus for GO animals was 28% longer than for SO rats (p<.05. While latency to clonic seizures was 24% longer in GO than SO rats, this was an artifact of the sound gradually reaching AGS-inducing intensity for the GO group. Because sensory neurons respond to change, sudden onset sound may allow more adaptation of AGSprone inferior colliculus neurons than a gradual onset seizure-inducing stimulus. Ramping to a maximum intensity sound may produce greater seizure severity due to a greater number of neurons remaining.

  7. Sudden relaminarisation and lifetimes in forced isotropic turbulence

    CERN Document Server

    Linkmann, Moritz

    2015-01-01

    We demonstrate an unexpected connection between isotropic turbulence and wall-bounded shear flows. We perform direct numerical simulations of isotropic turbulence forced at large scales at moderate Reynolds numbers and observe sudden transitions from chaotic dynamics to a spatially simple flow, analogous to the laminar state in wall-bounded shear flows. We find that the survival probabilities of turbulence are exponential and the typical lifetimes increase super-exponentially with the Reynolds number. Our results suggest that both isotropic turbulence and wall-bounded shear flows share the same phase-space dynamics.

  8. Experimental Demonstration of Largeness in Bipartite Entanglement Sudden Death

    Institute of Scientific and Technical Information of China (English)

    PENG Liang; HUANG Yun-Feng; LI Li; LIU Bi-Heng; LI Chuan-Feng; GUO Guang-Can

    2011-01-01

    Quantum coherence is the most distinct feature of quantum mechanics.However,inevitable decoherence processes will finlly destroy it and make the"Schr(o)dinger's cat" invisible in our classical world. In this "quantumto-classical transition",the so-called "largeness" plays a critical role. We experimentally study the largeness phenomena in the bipartite entanglement decay process through a depolarizing channel with two-photon entangled states generated from a spontaneous parametric down-conversion source.Our experiment demonstrates how the speed of entanglement decay and the time when "entanglement sudden death" happens depend on the size of the system exposed to the environment noise.

  9. Cause of sudden magnetic reconnection in a laboratory plasma.

    Science.gov (United States)

    Choi, S; Craig, D; Ebrahimi, F; Prager, S C

    2006-04-14

    The cause for sudden reconnection in reversed field pinch plasmas is determined experimentally for two cases: large reconnection events (the sawtooth crash) and small reconnection events during improved confinement. We measure the term in the MHD equations which represents the driving (or damping) of edge tearing modes due to the axisymmetric magnetic field. The term is negative for large reconnection events (the modes are stable, implying that reconnection may be driven by nonlinear coupling to other modes) and positive for small reconnection events (modes are unstable, reconnection is spontaneous).

  10. Living after sudden death: A case report of Naxos disease

    Directory of Open Access Journals (Sweden)

    Jose Alberto Garcia Noain

    2012-01-01

    Full Text Available Naxos disease is a recessive inherited condition with arrhythmogenic right ventricular dysplasia (ARVD and a peculiar cutaneous phenotype (woolly hair and a palmoplantar keratoderma. Woolly hair appears from birth, palmoplantar keratoderma develops during childhood and cardiomyopathy is clinically manifested by adolescence. Patients present with syncope, sustained ventricular tachycardia or sudden death. We report a case of a 14 year old boy from Spain, who was admitted into our emergency room after being resuscitated from cardiac arrest, secondary to malignant ventricular tachycardia that developed while he was playing basketball.

  11. Sudden sensorineural hearing loss after non-otologic surgery.

    Science.gov (United States)

    Page, Joshua Cody; Peters, Bob

    2015-01-01

    Sudden sensorineural hearing loss following non-otologic surgery is a rare event described in the medical literature. Cardiopulmonary bypass surgery is most commonly associated with this type of hearing loss. Our case report and review of the literature describe two cases with postoperative hearing loss - neither of which are cardiac surgeries - making them exceedingly rare in the medical literature. Regardless of the rarity of this unfortunate event, the possibility for permanent hearing loss is a potentially devastating unanticipated complication and one that all surgeons should be aware.

  12. Alternating sudden sensorineural hearing loss in demyelinating disorders

    Directory of Open Access Journals (Sweden)

    Rajeev Gupta

    2016-01-01

    Full Text Available Multiple sclerosis (MS is the most common demyelinating disease of the central nervous system. MS is a neuromotor disorder which progresses with remissions and relapsing periods. Symptoms of MS plaques may regress completely or heal by leaving sequelae. Symptomatology of MS may be very variable. These symptoms usually show variations depending on the localization of demyelinated plaques in the central nervous system. In this case, we are presenting a case of sudden sensorineural hearing loss in alternate ears with magnetic resonance images suggestive of demyelinating disorders. These hearing losses are improved completely as disease has remission and relapsing periods.

  13. Increased risk of sudden cardiac arrest in obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Warnier, Miriam Jacoba; Blom, Marieke Tabo; Bardai, Abdennasser

    2013-01-01

    BACKGROUND: We aimed to determine whether (1) patients with obstructive pulmonary disease (OPD) have an increased risk of sudden cardiac arrest (SCA) due to ventricular tachycardia or fibrillation (VT/VF), and (2) the SCA risk is mediated by cardiovascular risk-profile and/or respiratory drug use....... METHODS: A community-based case-control study was performed, with 1310 cases of SCA of the ARREST study and 5793 age, sex and SCA-date matched non-SCA controls from the PHARMO database. Only incident SCA cases, age older than 40 years, that resulted from unequivocal cardiac causes...

  14. EXPERIMENTAL INVESTIGATION OF CAVITATION IN A SUDDEN EXPANSION PIPE

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-min; YANG Qing; WANG Yu-rong; XU Wei-lin; CHEN Jian-gang

    2011-01-01

    For sudden expansion pipes, experiments were carried out to study the cavitation inception for various enlargement ratios in high speed flows.The flow velocity of the prototype reaches 50 m/s in laboratory.The relationship between the expansion ratio and the incipient cavitation number is obtained.The scale and velocity effects are revealed.It is shown that Keller's revised formula should be modified to calculate the incipient cavitation number when the forecasted velocity of the flows in the prototype exceeds the experimental velocity.

  15. Sudden death of a child due to respiratory diphtheria.

    Science.gov (United States)

    Swain, Rajanikanta; Behera, Chittaranjan; Arava, Sudheer Kumar; Kundu, Naveen

    2016-06-01

    A four-year-old girl presented to the emergency department with respiratory distress. Death occurred despite attempted resuscitation. The illness was not clinically diagnosed. Her father revealed that she had a fever and sore throat for the last four days and was not immunised for diphtheria. Characteristic gross and microscopic pathology of respiratory diphtheria and microbiological findings were observed. The cause of death was acute respiratory failure consequent upon upper airway obstruction from diphtheria. Forensic pathologists should remember that the diphtheria cases can cause sudden death especially in developing countries. © The Author(s) 2016.

  16. Ebstein's Anomaly, Left Ventricular Noncompaction, and Sudden Cardiac Death

    Science.gov (United States)

    McGee, Michael; Warner, Luke; Collins, Nicholas

    2015-01-01

    Ebstein's anomaly is a congenital disorder characterized by apical displacement of the septal leaflet of the tricuspid valve. Ebstein's anomaly may be seen in association with other cardiac conditions, including patent foramen ovale, atrial septal defect, and left ventricular noncompaction (LVNC). LVNC is characterized by increased trabeculation within the left ventricular apex. Echocardiography is often used to diagnose LVNC; however, magnetic resonance (MR) imaging offers superior characterization of the myocardium. We report a case of sudden cardiac death in a patient with Ebstein's anomaly with unrecognized LVNC noted on post mortem examination with screening documenting the presence of LVNC in one of the patient's twin sons. PMID:26240764

  17. Capillary-Gravity Waves Generated by a Sudden Object Motion

    CERN Document Server

    Closa, Fabien; Raphael, Elie

    2010-01-01

    We study theoretically the capillary-gravity waves created at the water-air interface by a small object during a sudden accelerated or decelerated rectilinear motion. We analyze the wave resistance corresponding to the transient wave pattern and show that it is nonzero even if the involved velocity (the final one in the accelerated case, the initial one in the decelerated case) is smaller than the minimum phase velocity $c_{min}=23 \\mathrm{cm s^{-1}}$. These results might be important for a better understanding of the propulsion of water-walking insects where accelerated and decelerated motions frequently occur.

  18. [Hypertensive crisis and sudden change of vision in young patients].

    Science.gov (United States)

    Cortés Fernández, M S; Martín-Castillejos, C; Armario, P

    2016-01-01

    The sudden change in vision is a medical emergency that must be evaluated immediately to rule out important institutions as systemic vasculitis or ischemic stroke. Its association with hypertensive crisis makes it necessary to rule out accelerated-malignant hypertension, which is accompanied by other retinal disorders (exudates and hemorrhages) and adrenal involvement. Nonarteritic anterior ischemic optic neuropathy (AION) is another entity to consider, as is it not uncommon in the young (12.7% in a series of 848 cases). Its association with hypertension has been described in 32% of cases.

  19. Sudden stretching of a four layered composite plate

    Science.gov (United States)

    Sih, G. C.; Chen, E. P.

    1980-01-01

    An approximate theory of laminated plates is developed by assuming that the extensioral and thickness mode of vibration are coupled. The mixed boundary value crack problem of a four layered composite plate is solved. Dynamic stress intensity factors for a crack subjected to suddenly applied stress are found to vary as a function of time and depend on the material properties of the laminate. Stress intensification in the region near the crack front can be reduced by having the shear modulus of the inner layers to be larger than that of the outer layers.

  20. Pheochromocytoma Sudden Death as a Result of Cerebral Hemorrhage

    Directory of Open Access Journals (Sweden)

    Muhammed Ziya Kır

    2005-12-01

    Full Text Available Pheochromocytoma is an endocrine tumor characterized by severe hypertension associated with cerebral, cardiac, and renal complications, hypotension or even shock and sudden death. Most pheochromocytoma cases remain obscene clinically, fatal outcome is mostly related with such misdiagnosis. A 17-year-old girl with a history of chronic headache who had not been evaluated clinically died unexpectedly. The autopsy performed in the mortuary section of the council of forensic medicine revealed a pheochromocytoma and intraventricular cerebral bleeding. This case accentuates that pheochromocytomas, if remaining undiagnosed, may prove fatal. Key words: pheochromocytoma; death; autopsy

  1. SUDDEN ONSET OF DOUBLE ELEVATOR PALSY: A RARE CLINICAL ENTITY

    Directory of Open Access Journals (Sweden)

    Sundip

    2014-01-01

    Full Text Available Double elevator palsy (DEP currently known as Monocular Elevation Deficit is a rare condition characterized by restricted elevation of one eye in all positions of up gaze . Clinically it presents as a unilateral restriction of superior rectus (SR and inferior oblique (IO. We present a case report of DEP in 3 year old boy who presented with sudden onset of DEP in right eye in our OPD. Very little information on acquired causes of DEP is available. Diagnosis , differential diagnosis and m anagement are discussed and then the literature is reviewed.

  2. Sudden unexpected infant death due to fibroma of the heart.

    Science.gov (United States)

    Meissner, C; Minnasch, P; Gafumbegete, E; Reiter, A; Gerling, I; Oehmichen, M

    2000-05-01

    A 7-month-old previously healthy female infant was found dead in her crib by her mother shortly after having been laid down to sleep following the noontime feeding. Because the child did not suffer from an acute illness and no other evidence pointed to a cause of death, it was initially assumed by the police that she had died of sudden infant death syndrome. At autopsy, however, the cause of death was determined to be cardiac arrhythmia secondary to fibroma of the heart.

  3. Gravity wave effects in the thermosphere during sudden stratospheric warmings and vertical coupling between the lower and upper atmosphere

    Science.gov (United States)

    Yiǧit, Erdal; Medvedev, Alexander S.

    2016-07-01

    Gravity waves are primarily generated in the lower atmosphere, propagate upward, and have profound effects not only in the middle atmosphere but also at much higher altitudes. However, their effects in the upper atmosphere beyond the turbopause ( 105 km) have not been sufficiently studied. Using a general circulating model extending from the lower atmosphere to upper thermosphere and incorporating a whole atmosphere nonlinear parameterization of small-scale GWs developed by Yiǧit et al. (2008)}, we demonstrate that not only GWs penetrate into the thermosphere above the turbopause but also produce substantial dynamical and thermal effects that are comparable to ion drag and Joule heating. During sudden stratospheric warmings, GW propagation in the thermosphere is enhanced by more than a factor of three (Yiǧit and Medvedev, 2012)}, producing appreciable body forcing of up to 600 m s^{-1} day^{-1} around 250-300 km. The resultant impact on the variability of the thermospheric circulation can exceed ± 50% depending on the phase of the sudden warming (Yiǧit et al., 2014)}. References: Yiǧit, E., and A. S. Medvedev (2012), Gravity waves in the thermosphere during a sudden stratospheric warming, Geophys. Res. Lett., 39, L21101, doi:10.1029/2012GL053812. Yiǧit, E., A. D. Aylward, and A. S. Medvedev (2008), Parameterization of the effects of vertically propagating gravity waves for thermosphere general circulation models: Sensitivity study, J. Geophys. Res., 113, D19106, doi:10.1029/2008JD010135. Yiǧit, E., A. S. Medvedev, S. L. England, and T. J. Immel (2014), Simulated vari- ability of the high-latitude thermosphere induced by small-scale gravity waves during a sudden stratospheric warming, J. Geophys. Res. Space Physics, 119, doi:10.1002/2013JA019283.

  4. Analysis of caloric test responses in sudden hearing loss.

    Science.gov (United States)

    Shih, Cheng-Ping; Chou, Yu-Ching; Chen, Hsin-Chien; Lee, Jih-Chin; Chu, Yueng-Hsiang; Wang, Chih-Hung

    2017-02-01

    Sudden sensorineural hearing loss is characterized by a rapid-onset hearing loss that develops within 3 days. Vertigo may also be present. We conducted a retrospective study to investigate whether the severity of a loss of caloric function is associated with the initial hearing loss and with hearing recovery. Our study population was made up of 135 patients-67 men and 68 women, aged 25 to 71 years (mean: 50.9)-with sudden sensorineural hearing loss who had undergone bithermal caloric testing. We compared various patient factors according to patients' hearing level and their response to caloric testing. We also analyzed the canal paresis (CP) value in patients with an abnormal caloric response according to three factors: disease severity, vertigo, and hearing recovery, and we evaluated the correlation between the loss of caloric function and hearing outcomes. We found that an abnormal caloric response was significantly associated with a profound hearing loss at presentation, the presence of vertigo, and poor hearing recovery. Among patients with an abnormal caloric response, the CP value was significantly correlated with hearing recovery (r = 0.503, p = 0.001). Poor hearing recovery was seen in 80% of patients with a CP value of ≥40% but in only 25% of patients with a value of hearing recovery was worse in the patients with a CP value of ≥40% (p = 0.002). We conclude that a CP value of ≥40% is a significant prognostic factor for an unfavorable treatment outcome.

  5. Sudden onset unilateral sensorineural hearing loss after rabies vaccination.

    Science.gov (United States)

    Okhovat, Saleh; Fox, Richard; Magill, Jennifer; Narula, Antony

    2015-12-15

    A 33-year-old man developed profound sudden onset right-sided hearing loss with tinnitus and vertigo, within 24 h of pretravel rabies vaccination. There was no history of upper respiratory tract infection, systemic illness, ototoxic medication or trauma, and normal otoscopic examination. Pure tone audiograms (PTA) demonstrated right-sided sensorineural hearing loss (thresholds 90-100 dB) and normal left-sided hearing. MRI internal acoustic meatus, viral serology (hepatitis B, C, HIV and cytomegalovirus) and syphilis screen were normal. Positive Epstein-Barr virus IgG, viral capsid IgG and anticochlear antibodies (anti-HSP-70) were noted. Initial treatment involved a course of high-dose oral prednisolone and acyclovir. Repeat PTAs after 12 days of treatment showed a small improvement in hearing thresholds. Salvage intratympanic steroid injections were attempted but failed to improve hearing further. Sudden onset sensorineural hearing loss (SSNHL) is an uncommon but frightening experience for patients. This is the first report of SSNHL following rabies immunisation in an adult.

  6. Endothelial Dysfunction in Idiopathic Sudden Sensorineural Hearing Loss: A Review

    Science.gov (United States)

    Quaranta, Nicola; De Ceglie, Vincenzo; D’Elia, Alessandra

    2016-01-01

    An endothelial dysfunction has been described in idiopathic sudden sensorineural hearing loss (ISSHL) patients. The purpose of our review was to: i) identify, evaluate and review recent research about cardiovascular risk factors involvement and signs of endothelial dysfunction in ISSHL; ii) implication of these discovering in clinical practice and future research. A Medline literature search was conducted to identify any study on the involvement of endothelial dysfunction in ISSHL, published in the English language in the last decade. The following MEDLINE search terms were used: sudden sensorineural hearing loss (SSHL) and endothelial dysfunction (text words). Additional studies were identified by hand searching the references of original articles and review articles. Studies were not excluded on the basis of the qualitative or quantitative definitions of SSHL, treatment regimens, or outcome measures. Data were extracted from included papers by a reviewer. Information on the patients, investigations, methods, interventions, and outcomes were systematically analyzed. Characteristics and results of all included studies were reviewed systematically. High levels of adhesion molecules, hyperhomocysteinemia and lower folate levels, unbalanced oxidative status, a lower value of flow-mediated dilatation of brachial artery and a reduced percentage of circulating endothelial progenitor cells in patients affected by ISSHL support the hypothesis that this syndrome should be considered as a microcirculation disorder based on endothelial dysfunction and drive clinicians to implement all the traditional strategies used for preventing cardiovascular events, to also reduce the likelihood of ISSHL occurrence. PMID:27588164

  7. Endothelial dysfunction in idiopathic sudden sensorineural hearing loss: a review

    Directory of Open Access Journals (Sweden)

    Nicola Quaranta

    2016-07-01

    Full Text Available An endothelial dysfunction has been described in idiopathic sudden sensorineural hearing loss (ISSHL patients. The purpose of our review was to: i identify, evaluate and review recent research about cardiovascular risk factors involvement and signs of endothelial dysfunction in ISSHL; ii implication of these discovering in clinical practice and future research. A Medline literature search was conducted to identify any study on the involvement of endothelial dysfunction in ISSHL, published in the English language in the last decade. The following MEDLINE search terms were used: sudden sensorineural hearing loss (SSHL and endothelial dysfunction (text words. Additional studies were identified by hand searching the references of original articles and review articles. Studies were not excluded on the basis of the qualitative or quantitative definitions of SSHL, treatment regimens, or outcome measures. Data were extracted from included papers by a reviewer. Information on the patients, investigations, methods, interventions, and outcomes were systematically analyzed. Characteristics and results of all included studies were reviewed systematically. High levels of adhesion molecules, hyperhomocysteinemia and lower folate levels, unbalanced oxidative status, a lower value of flow-mediated dilatation of brachial artery and a reduced percentage of circulating endothelial progenitor cells in patients affected by ISSHL support the hypothesis that this syndrome should be considered as a microcirculation disorder based on endothelial dysfunction and drive clinicians to implement all the traditional strategies used for preventing cardiovascular events, to also reduce the likelihood of ISSHL occurrence.

  8. Causes and prevention of sudden cardiac death in the elderly.

    Science.gov (United States)

    Tung, Patricia; Albert, Christine M

    2013-03-01

    Sudden cardiac death (SCD) is a major cause of mortality in elderly individuals owing to a high prevalence of coronary heart disease, systolic dysfunction, and congestive heart failure (CHF). Although the incidence of SCD increases with age, the proportion of cardiac deaths that are sudden decreases owing to high numbers of other cardiac causes of death in elderly individuals. Implantable cardioverter-defibrillator (ICD) therapy has been demonstrated to improve survival and prevent SCD in selected patients with systolic dysfunction and CHF. However, ICD therapy in elderly patients might not be effective because of a greater rate of pulseless electrical activity underlying SCD and other competing nonarrhythmic causes of death in this population. Although under-represented in randomized trials of ICD use, elderly patients comprise a substantial proportion of the population that qualifies for and receives an ICD for primary prevention under current guidelines. Cardiac resynchronization therapy (CRT), which has been demonstrated to reduce mortality in selected populations with heart failure, is also more commonly used in this group of patients than in younger individuals. In this Review, we examine the causes of SCD in elderly individuals, and discuss the existing evidence for effectiveness of ICD therapy and CRT in this growing population.

  9. The spectrum of epidemiology underlying sudden cardiac death.

    Science.gov (United States)

    Hayashi, Meiso; Shimizu, Wataru; Albert, Christine M

    2015-06-01

    Sudden cardiac death (SCD) from cardiac arrest is a major international public health problem accounting for an estimated 15%-20% of all deaths. Although resuscitation rates are generally improving throughout the world, the majority of individuals who experience a sudden cardiac arrest will not survive. SCD most often develops in older adults with acquired structural heart disease, but it also rarely occurs in the young, where it is more commonly because of inherited disorders. Coronary heart disease is known to be the most common pathology underlying SCD, followed by cardiomyopathies, inherited arrhythmia syndromes, and valvular heart disease. During the past 3 decades, declines in SCD rates have not been as steep as for other causes of coronary heart disease deaths, and there is a growing fraction of SCDs not due to coronary heart disease and ventricular arrhythmias, particularly among certain subsets of the population. The growing heterogeneity of the pathologies and mechanisms underlying SCD present major challenges for SCD prevention, which are magnified further by a frequent lack of recognition of the underlying cardiac condition before death. Multifaceted preventative approaches, which address risk factors in seemingly low-risk and known high-risk populations, will be required to decrease the burden of SCD. In this Compendium, we review the wide-ranging spectrum of epidemiology underlying SCD within both the general population and in high-risk subsets with established cardiac disease placing an emphasis on recent global trends, remaining uncertainties, and potential targeted preventive strategies.

  10. [Clinical features associated with sudden hearing loss in children].

    Science.gov (United States)

    Taiji, Hidenobu; Morimoto, Noriko

    2012-07-01

    Sudden sensorineural hearing loss is usually unilateral, and the cause is not identified in most adult cases. However, a specific cause has frequently been found in the case of children, in whom idiopathic sudden sensorineural hearing loss (ISHL) is comparatively rare. We investigated 20 cases of acute unilateral sensorineural hearing loss in children associated with a certain disease, but which was first diagnosed as ISHL. Thirteen patients aged 6 to 16 years old were diagnosed as having psychogenic (functional) hearing loss. Discrepancies in behavioral and objective tests are most valuable when functional hearing loss is suspected. Elevated pure-tone thresholds associated with normal distortion product otoacoustic emissions (DPOAEs) enable prompt further investigation. There are several conditions that may mimic functional hearing loss, so auditory brainstem response (ABR) testing is necessary to verify the actual cause. The unilateral profound hearing loss in 2 patients aged 7 and 11 years old was due to asymptomatic mumps proven by detecting the mumps IgM antibody. Total hearing recovery in the 125-1000 Hz frequencies occurred in one case. In 5 patients aged 6 to 12 years old with acute hearing loss and vertigo, high resolution CT imaging showed an abnormally enlarged vestibular aqueduct on the affected side. Large vestibular aqueduct syndrome should be considered in acute high-frequency sloping hearing loss with an A-B gap at low frequencies.

  11. Sudden cardiac death with triple pathologies: A case report

    Directory of Open Access Journals (Sweden)

    R. Razuin

    2017-06-01

    Full Text Available Sudden cardiac death in young adults may be associated with rare cardiomyopathies such as left ventricular noncompaction (LVNC and arrhythmogenic right ventricular (ARVC cardiomyopathies. LVNC is characterised by hypertrabeculations and deep recesses of the left ventricle. ARVC presents with thin myocardium as a result of extensive fibro-fatty infiltrations. In both conditions, death may be due to arrhythmia, thromboembolic events or heart failure. We report a case of a 21-year old athletic young man who collapsed at the futsal court right after the game. He was resuscitated but expired at the hospital after a brief admission. A week earlier, he had a similar episode of syncope and revived through cardio-pulmonary resuscitation at the site. Post mortem examination showed extensive acute myocardial infarction (AMI involving the papillary muscles and the left ventricular wall. Features of LVNC were also observed. On top of that, the right ventricle showed patchy thin myocardium as the wall was largely comprised of fat. Histology examination confirmed the presence of AMI and massive fibro-fatty infiltrations of the right ventricle. This unfortunate young man had co-existing cardiomyopathies which is rare indeed. As he succumbed to AMI, this mechanism of death is also uncommonly associated with neither LVNC nor ARVC. In conclusion, young and physically active individuals may not be spared of sudden cardiac death. Mild and non-specific symptoms should not be taken lightly as it may be the subtle signs of cardiomyopathies.

  12. Sudden infant death due to Lactococcal infective endocarditis.

    Science.gov (United States)

    Taniguchi, K; Nakayama, M; Nakahira, K; Nakura, Y; Kanagawa, N; Yanagihara, I; Miyaishi, S

    2016-03-01

    Infective endocarditis (IE) of infants is rare, most of which occur associated with congenital heart disease or its cardiac surgery. We experienced a case of sudden death of a four-month-old male infant without congenital heart disease. It was elucidated by postmortem examination that the dead had suffered severe IE, which led him to death. In the microbiological genetic analysis using histological section, the pathogen causing inflammation in the present case was identified as Lactococcus lactis subspecies, although Staphylococci have been reported to be common and important one. Previously reported infectious diseases by Lactococcus lactis subspecies were all adult cases and this is the first report of an infantile death due to Lactococcal IE according to our knowledge. Any fatal disease may be included in sudden death cases targeted for forensic autopsy, even if it is rare. It is expected for forensic pathologists that they note such case and share each experience among themselves and other medical fields to develop a strategy for prevention.

  13. Sudden infant death syndrome: diagnostic practices and investigative policies, 2004.

    Science.gov (United States)

    Camperlengo, Lena T; Shapiro-Mendoza, Carrie K; Kim, Shin Y

    2012-09-01

    Using a 2004 population-based survey of all US medical examiner and coroner offices, we examined the characteristics of offices accepting an infant death case and calculated the percentage of offices that had death scene investigation or autopsy policies for the investigation of sudden unexpected infant death (SUID). We also calculated the percentage of offices that used and did not use sudden infant death syndrome (SIDS) as a cause of death, and we compared differences in characteristics among those offices.Of medical examiner and coroner offices, 52% did not report an infant death in 2004. Of the 7957 infant deaths reported, 43% occurred in jurisdictions that experienced 1 or 2 infant deaths. Of the offices that used SIDS as a classification, 34% did not have policies for conducting death scene investigations and autopsies for SUID. At least 5% of offices that reported an infant death did not use SIDS as a cause of death classification. These findings have important implications for understanding recent trends in SIDS and SUID. Supporting the implementation of national standards for investigating and certifying infant deaths could provide guidelines for consistent practices in medical examiner and coroner offices.

  14. The physiological determinants of sudden infant death syndrome.

    Science.gov (United States)

    Garcia, Alfredo J; Koschnitzky, Jenna E; Ramirez, Jan-Marino

    2013-11-01

    It is well-established that environmental and biological risk factors contribute to Sudden Infant Death Syndrome (SIDS). There is also growing consensus that SIDS requires the intersection of multiple risk factors that result in the failure of an infant to overcome cardio-respiratory challenges. Thus, the critical next steps in understanding SIDS are to unravel the physiological determinants that actually cause the sudden death, to synthesize how these determinants are affected by the known risk factors, and to develop novel ideas for SIDS prevention. In this review, we will examine current and emerging perspectives related to cardio-respiratory dysfunctions in SIDS. Specifically, we will review: (1) the role of the preBötzinger complex (preBötC) as a multi-functional network that is critically involved in the failure to adequately respond to hypoxic and hypercapnic challenges; (2) the potential involvement of the preBötC in the gender and age distributions that are characteristic for SIDS; (3) the link between SIDS and prematurity; and (4) the potential relationship between SIDS, auditory function, and central chemosensitivity. Each section underscores the importance of marrying the epidemiological and pathological data to experimental data in order to understand the physiological determinants of this syndrome. We hope that a better understanding will lead to novel ways to reduce the risk to succumb to SIDS.

  15. Endothelial Dysfunction in Idiopathic Sudden Sensorineural Hearing Loss: A Review.

    Science.gov (United States)

    Quaranta, Nicola; De Ceglie, Vincenzo; D'Elia, Alessandra

    2016-04-20

    An endothelial dysfunction has been described in idiopathic sudden sensorineural hearing loss (ISSHL) patients. The purpose of our review was to: i) identify, evaluate and review recent research about cardiovascular risk factors involvement and signs of endothelial dysfunction in ISSHL; ii) implication of these discovering in clinical practice and future research. A Medline literature search was conducted to identify any study on the involvement of endothelial dysfunction in ISSHL, published in the English language in the last decade. The following MEDLINE search terms were used: sudden sensorineural hearing loss (SSHL) and endothelial dysfunction (text words). Additional studies were identified by hand searching the references of original articles and review articles. Studies were not excluded on the basis of the qualitative or quantitative definitions of SSHL, treatment regimens, or outcome measures. Data were extracted from included papers by a reviewer. Information on the patients, investigations, methods, interventions, and outcomes were systematically analyzed. Characteristics and results of all included studies were reviewed systematically. High levels of adhesion molecules, hyperhomocysteinemia and lower folate levels, unbalanced oxidative status, a lower value of flow-mediated dilatation of brachial artery and a reduced percentage of circulating endothelial progenitor cells in patients affected by ISSHL support the hypothesis that this syndrome should be considered as a microcirculation disorder based on endothelial dysfunction and drive clinicians to implement all the traditional strategies used for preventing cardiovascular events, to also reduce the likelihood of ISSHL occurrence.

  16. Sudden Unexplained Nocturnal Death Syndrome in Central China (Hubei)

    Science.gov (United States)

    Chen, Zhenglian; Mu, Jiao; Chen, Xinshan; Dong, Hongmei

    2016-01-01

    Abstract A retrospective study was conducted at Tongji Forensic Medical Center in Hubei (TFMCH) from 1999 to 2014. Forty-nine cases of sudden unexplained nocturnal death syndrome (SUNDS) were collected. The SUNDS rate was 1.0% in the total number of cases, in which an incidence was fluctuating over the years. Interestingly, April and January, and 3:00 to 6:00 am were the peak months and times of death. Among the decedents, farmers and migrant workers accounted for 67.3%. The syndrome predominantly attacked males in their 30s. One victim had sinus tachycardia. Thirteen victims (26.5%) were witnessed and had abnormal symptoms near death. Macroscopically, compared to sudden noncardiac deaths, the weights of brain, heart, and lungs had no statistical difference in SUNDS. Microscopically, the incidence of lung edema (45 cases, 91.8%) was significantly higher in SUNDS group than in the control group (27 cases, 55.1%). 82.9% of 35 SUNDS cases examined displayed minor histological anomalies of the cardiac conduction system (CCS), including mild or moderate fatty, fibrous or fibrofatty tissue replacement, insignificant stenosis of node artery, and punctate hemorrhage in the node area. These findings suggested that minor CCS abnormalities might be the substrates for some SUNDS deaths. Therefore, SUNDS victims might suffer ventricular fibrillation and acute cardiopulmonary failure before death. Further in-depth studies are needed to unveil the underlying mechanisms of SUNDS. PMID:26945374

  17. Sudden death in infancy due to bicuspid aortic valve.

    Science.gov (United States)

    Karayel, Ferah; Ozaslan, Abdi; Turan, Arzu Akcay; Pakis, Isil; Ketenci, Cetin; Eroglu, Ayse Guler

    2006-09-01

    Symptoms of bicuspid aortic valve usually occur in the age group of 50-70 years, but rarely, it can also lead to sudden unexpected death in infancy and early childhood. The autopsy of a 2-month-old baby boy, found dead in his cot, revealed the heart weight as 25 g, and the macroscopic examination showed the circumference of the aortic valve consisting of two leaflets as 8 mm. The thickness of the left ventricle, right ventricle, and septum was measured as 8, 7, and 10 mm, respectively. Microscopically, the heart revealed hypertrophic changes of myocytes. Subendocardial areas displayed necrosis of myocytes, and severe and diffuse ischemic changes characterized by loss of myofibers and vacuolization. Interstitial pneumonia was identified in the lungs. Death occurred as a result of a congenital bicuspid aortic valve obstructing the left ventricular outflow tract complicated by lung infection. As there are only a few reported cases in infancy, and congenital bicuspid aortic valve can lead to sudden unexpected death, this case is presented to the forensic community.

  18. Sudden sensorineural hearing loss as the first manifestation of chronic myeloid leukaemia: case report.

    Science.gov (United States)

    Diao, M; Tian, F; Sun, J

    2014-11-01

    Sudden sensorineural hearing loss rarely occurs in patients with chronic myeloid leukaemia. We present a case report of a patient who presented with sudden sensorineural hearing loss as the first manifestation of chronic myeloid leukaemia, and review the mechanisms responsible for sudden sensorineural hearing loss in leukaemic patients. A 31-year-old female presented to our clinic with unilateral sudden sensorineural hearing loss and tinnitus. Pure tone audiometry revealed profound sensorineural hearing loss in the left ear at all frequencies. During an investigation into her hearing loss, the patient was found to have chronic myeloid leukaemia. Every case of sudden sensorineural hearing loss must be carefully evaluated, and haematological disorders must be considered in the differential diagnosis of sudden hearing loss.

  19. Profile of sudden death in an adult population (1999-2008).

    LENUS (Irish Health Repository)

    Downes, M R

    2010-06-01

    Sudden death is the sudden and unexpected death of an individual within 24 hours of symptom onset. The vast majority of these cases are found, at autopsy, to be due to underlying ischaemic cardiac disease. We retrospectively reviewed all adult post mortems performed at Beaumont Hospital over a decade (1999-2008). Our aim was to identify all sudden death cases (natural and accidental) and subclassify them according to age profile and organ system involved. We identified 1230 sudden death cases in the review period with 775 (63%) deaths attributable to ischaemic heart disease. The rate of sudden death remained constant over the decade with 663 (54%) deaths occurring in the first five years. Our negative autopsy rate was 2.8% corresponding to 35 cases. This is the first Irish study to retrospectively review all adult sudden deaths within a defined catchment area and analyse them as outlined above.

  20. A clinical study of microcirculatory disturbance in Chinese patients with sudden deafness.

    Science.gov (United States)

    Lu, Yuan-Yuan; Jin, Zhe; Tong, Bu-Sheng; Yang, Jian-Ming; Liu, Ye-Hai; Duan, Maoli

    2008-11-01

    Cochlear microcirculation disturbance is closely associated with sudden deafness. To investigate the relationship between cochlear microcirculation and sudden deafness. Clinical laboratory parameters (clinical chemistry, hemorheology, hematology, and hemostasis determinations) were studied in 86 patients with sudden deafness and 30 healthy control subjects. The levels of total cholesterol (TCH), triglyceride (TG), and lipoprotein A were significantly higher in patients with sudden deafness than in control subjects. Plasma viscosity, ratio viscosity of whole blood, reduced viscosity of whole blood, high and low shear relative viscosity of whole blood, index of red blood cells transmutation, and fibrinogen level in the plasma of patients with sudden sensorineural hearing loss (SSNHL) were also significantly elevated in comparison with those in control subjects. White-collar workers with psychological and behavioral abnormalities tend to suffer from sudden deafness.

  1. Resolution of Sudden Sensorineural Hearing Loss Following a Roller Coaster Ride

    OpenAIRE

    Kumar, Aman; Sinha, Amrita; Al-Waa, Ahmad M.

    2011-01-01

    We report a case of sudden unilateral sensorineural hearing loss of sudden onset during an aeroplane flight, which completely resolved during a roller coaster ride at Alton Towers theme park. A review of the literature concerning sudden idiopathic sensorineural hearing loss and spontaneous resolution are discussed. Initially, pure-tone audiometry showed a profound sensorineural hearing loss in the right ear and mild sensorineural hearing loss in the left ear (of note, the hearing was normal p...

  2. Investigation for Transient Phenomena in Concentric Annular Turbulent Flow with Sudden Outer-Wall-Rotation

    OpenAIRE

    岡本, 正芳; 永江, 聡美; Masayoshi, OKAMOTO; Satomi, NAGAE; 静岡大工; 東北大流体研; Dept. of Mech. Eng., Shizuoka Univ.; Institute of Fluid Science, Tohoku Univ.

    2007-01-01

    Transient phenomena in turbulent concentric annular pipe flow with sudden outer-wall rotation were investigated by means of the direct numerical simulation (DNS). Due to the sudden rotation, the wall friction becomes small and the flow is stabilized. In the transient state, the axial mean velocity profile changes drastically and the Reynolds stresses vanish near the outer wall. When the wall friction increases suddenly, the vortex structures are invigorated.

  3. Resolution of Sudden Sensorineural Hearing Loss Following a Roller Coaster Ride

    OpenAIRE

    Kumar, Aman; Sinha, Amrita; Al-Waa, Ahmad M.

    2011-01-01

    We report a case of sudden unilateral sensorineural hearing loss of sudden onset during an aeroplane flight, which completely resolved during a roller coaster ride at Alton Towers theme park. A review of the literature concerning sudden idiopathic sensorineural hearing loss and spontaneous resolution are discussed. Initially, pure-tone audiometry showed a profound sensorineural hearing loss in the right ear and mild sensorineural hearing loss in the left ear (of note, the hearing was normal p...

  4. Altered Contralateral Auditory Cortical Morphology in Unilateral Sudden Sensorineural Hearing Loss

    OpenAIRE

    Fan, Wenliang; Zhang, Wenjuan; Li, Jing; Zhao, Xueyan; Mella, Grace; Lei, Ping; Liu, Yuan; Wang, Haha; Cheng, Huamao; Shi, Hong; Xu, Haibo

    2015-01-01

    Objective: To investigate the cerebral gray matter volume alterations in unilateral sudden sensorineural hearing loss patients within the acute period by the voxel-based morphometry method, and to determine if hearing impairment is associated with regional gray matter alterations in unilateral sudden sensorineural hearing loss patients. Study Design: Prospective case study. Setting: Tertiary class A teaching hospital. Patients: Thirty-nine patients with left-side unilateral sudden sensorineur...

  5. Predictive Value of Beat-to-Beat QT Variability Index across the Continuum of Left Ventricular Dysfunction: Competing Risks of Non-cardiac or Cardiovascular Death, and Sudden or Non-Sudden Cardiac Death

    Science.gov (United States)

    Tereshchenko, Larisa G.; Cygankiewicz, Iwona; McNitt, Scott; Vazquez, Rafael; Bayes-Genis, Antoni; Han, Lichy; Sur, Sanjoli; Couderc, Jean-Philippe; Berger, Ronald D.; de Luna, Antoni Bayes; Zareba, Wojciech

    2012-01-01

    Background The goal of this study was to determine the predictive value of beat-to-beat QT variability in heart failure (HF) patients across the continuum of left ventricular dysfunction. Methods and Results Beat-to-beat QT variability index (QTVI), heart rate variance (LogHRV), normalized QT variance (QTVN), and coherence between heart rate variability and QT variability have been measured at rest during sinus rhythm in 533 participants of the Muerte Subita en Insuficiencia Cardiaca (MUSIC) HF study (mean age 63.1±11.7; males 70.6%; LVEF >35% in 254 [48%]) and in 181 healthy participants from the Intercity Digital Electrocardiogram Alliance (IDEAL) database. During a median of 3.7 years of follow-up, 116 patients died, 52 from sudden cardiac death (SCD). In multivariate competing risk analyses, the highest QTVI quartile was associated with cardiovascular death [hazard ratio (HR) 1.67(95%CI 1.14-2.47), P=0.009] and in particular with non-sudden cardiac death [HR 2.91(1.69-5.01), P<0.001]. Elevated QTVI separated 97.5% of healthy individuals from subjects at risk for cardiovascular [HR 1.57(1.04-2.35), P=0.031], and non-sudden cardiac death in multivariate competing risk model [HR 2.58(1.13-3.78), P=0.001]. No interaction between QTVI and LVEF was found. QTVI predicted neither non-cardiac death (P=0.546) nor SCD (P=0.945). Decreased heart rate variability (HRV) rather than increased QT variability was the reason for increased QTVI in this study. Conclusions Increased QTVI due to depressed HRV predicts cardiovascular mortality and non-sudden cardiac death, but neither SCD nor excracardiac mortality in HF across the continuum of left ventricular dysfunction. Abnormally augmented QTVI separates 97.5% of healthy individuals from HF patients at risk. PMID:22730411

  6. Thiol/disulphide homeostasis as a novel indicator of oxidative stress in sudden sensorineural hearing loss.

    Science.gov (United States)

    Dinc, M E; Ulusoy, S; Is, A; Ayan, N N; Avincsal, M O; Bicer, C; Erel, O

    2016-05-01

    To investigate a novel oxidative stress marker, thiol/disulphide literature homeostasis, in patients with idiopathic sudden sensorineural hearing loss, and to compare the results with healthy controls for the first time. Thirty-two patients with idiopathic sudden sensorineural hearing loss and 30 healthy individuals were included in the study. Serum native thiol, total thiol and disulphide levels were measured, and disulphide/native thiol and disulphide/total thiol ratios were determined in all subjects. Serum native thiol and total thiol levels were significantly lower in patients with sudden sensorineural hearing loss compared with controls (p sudden sensorineural hearing loss in those patients.

  7. Sudden death in young persons with uncontrolled asthma--a nationwide cohort study in Denmark

    DEFF Research Database (Denmark)

    Gullach, Anders Juul; Risgaard, Bjarke; Lynge, Thomas Hadberg;

    2015-01-01

    BACKGROUND: Asthma is a common chronic disease among young adults, and several studies have reported increased mortality rates in patients with asthma. However, no study has described sudden unexpected death in a nationwide setting in patients with uncontrolled asthma. We defined uncontrolled...... in preventing sudden unexpected deaths. We therefore aimed to describe clinical characteristics, symptoms, causes of death, and contact with the healthcare system prior to sudden unexpected death in young persons with uncontrolled asthma. METHODS: Through the review of death certificates, we found 625 sudden...

  8. Registry of Malignant Arrhythmias and Sudden Cardiac Death - Influence of Diagnostics and Interventions

    Science.gov (United States)

    2016-11-30

    Ventricular Tachycardia; Ventricular Fibrillation; Sudden Cardiac Death; Coronary Angiography; Electrophysiologic Testing (EP); Catheter Ablation; Percutaneous Coronary Intervention (PCI); Internal Cardioverter Defibrillator (ICD)

  9. [Related factor analysis of the degree of tinnitus in sudden sensorineural hearing loss patients].

    Science.gov (United States)

    Chen, Ping; Zhou, Jinhui

    2013-01-01

    To provide the theory basis for clinical diagnosis, treatment and prognosis of sudden deafness patients, we detected the relative factors of degree of tinnitus of the patients with sudden deafness. Prospective analysis was used to compare degree of tinnitus with sex, ears, age, degree of hearing lose, hearing curve type and curative effect of tinnitus and sudden deafness. Tinnitus was detected in 87.2% in the 70 patients who with sudden deafness, and the most and least degree of tinnitus patients was the degree 3 (32.9%) and the degree 5 and 6 (0). The total effective rate of sudden deafness and tinnitus was 66.2% and 74.3%, respectively. The statistical analysis shown the degree of tinnitus was not related to sex, ears, age, degree of hearing lose, auditory curve type and curative effect of tinnitus and sudden deafness (P > 0.05). There was a high rate of tinnitus occurrence in sudden deafness patients, and the moderate degree predominated. The curative effect of tinnitus was better than sudden deafness. There was no relationship between the degree of tinnitus and sex, ears, age, degree of hearing lose, auditory curve type and curative effect of tinnitus and sudden deafness.

  10. Parametric study on responses of a self-anchored suspension bridge to sudden breakage of a hanger.

    Science.gov (United States)

    Qiu, Wenliang; Jiang, Meng; Huang, Cailiang

    2014-01-01

    The girder of self-anchored suspension bridge is subjected to large compression force applied by main cables. So, serious damage of the girder due to breakage of hangers may cause the collapse of the whole bridge. With the time increasing, the hangers may break suddenly for their resistance capacities decrease due to corrosion. Using nonlinear static and dynamic analysis methods and adopting 3D finite element model, the responses of an actual self-anchored suspension bridge to sudden breakage of hangers are studied in this paper. The results show that the sudden breakage of a hanger causes violent vibration and large changes in internal forces of the bridge. In the process of the vibration, the maximum tension of hanger produced by breakage of a hanger exceeds 2.22 times its initial value, and the reaction forces of the bearings increase by more than 1.86 times the tension of the broken hanger. Based on the actual bridge, the influences of some factors including flexural stiffness of girder, torsion stiffness of girder, flexural stiffness of main cable, weight of girder, weight of main cable, span to sag ratio of main cable, distance of hangers, span length, and breakage time of hanger on the dynamic responses are studied in detail, and the influencing extent of the factors is presented.

  11. Parametric Study on Responses of a Self-Anchored Suspension Bridge to Sudden Breakage of a Hanger

    Directory of Open Access Journals (Sweden)

    Wenliang Qiu

    2014-01-01

    Full Text Available The girder of self-anchored suspension bridge is subjected to large compression force applied by main cables. So, serious damage of the girder due to breakage of hangers may cause the collapse of the whole bridge. With the time increasing, the hangers may break suddenly for their resistance capacities decrease due to corrosion. Using nonlinear static and dynamic analysis methods and adopting 3D finite element model, the responses of an actual self-anchored suspension bridge to sudden breakage of hangers are studied in this paper. The results show that the sudden breakage of a hanger causes violent vibration and large changes in internal forces of the bridge. In the process of the vibration, the maximum tension of hanger produced by breakage of a hanger exceeds 2.22 times its initial value, and the reaction forces of the bearings increase by more than 1.86 times the tension of the broken hanger. Based on the actual bridge, the influences of some factors including flexural stiffness of girder, torsion stiffness of girder, flexural stiffness of main cable, weight of girder, weight of main cable, span to sag ratio of main cable, distance of hangers, span length, and breakage time of hanger on the dynamic responses are studied in detail, and the influencing extent of the factors is presented.

  12. Characteristics of pressure drop for single-phase and two-phase flow across sudden contraction in microtubes

    Institute of Scientific and Technical Information of China (English)

    LI Zhuo; YU Jian; MA ChongFang

    2008-01-01

    Single-phase and gas-liquid two-phase pressure drops caused by a sudden contraction in microtubes were experimentally investigated at room temperature and atmospheric pressure, using nitrogen and water. The experimental results on pressure drop with a novel measurement method, the tiny gaps on the tubes, were used to characterize the sudden contraction pressure drop for tube diameters from 850 to 330 μm. The ranges of the gas and liquid superficial velocity were 2.55-322.08 and 0.98-9.78 m/s in the smaller tube respectively. In single-phase flow experiments, the contraction loss coefficients were larger than the experimental results from conventional tubes in the laminar flow. While in the turbulent flow, the contraction loss coefficients were slightly smaller than those from conventional tubes and predicted well by Kc=0.5×1-σ2)0.75. In two-phase flow experiments, the slip flow model with a velocity slip ratio S=(ρL/ρG)1/3 showed a good prediction that reveals the occurrence of velocity slip. An empirical correlation for two-phase flow pressure drops caused by the sudden contraction was developed based on the proposed contraction loss coefficients correlation for single-phase flow and Martinelli factor.

  13. [Analyses prognostic factors relevant to sudden sensorineural hearing loss].

    Science.gov (United States)

    Wang, Jun; Xiao, Shuifang; Zeng, Zhengang; Zhen, Zhen; Zhang, Xuexi; Lin, Feng; Dong, Mingmin; Lu, Wei; Qin, Zhaobing; Zuo, Bin; Bai, Xianfeng

    2015-06-01

    To investigate the prognostic factors relevant to sudden sensorineural hearing loss. The internationally accepted standardized clinical research methods, unified design, and unified program were adopted to conduct the prospective clinical multi-center study. The sudden deafness patients between 18 to 65 years old, with the course of this disorder less than two weeks, and without any medical treatments were collected, and then, divided into four types according to the hearing curve: type A, acute sensorineural hearing loss in low tone frequencies; type B, acute sensorineural hearing loss in high tone frequencies; type C, acute sensorineural hearing loss in all frequencies; and type D, total deafness. The factors, in terms of age, gender, type of initial audiogram, time delay before the first visit, and severity of hearing loss, were included in the analyses. A total of 1 024 cases with single side sudden deafness were collected in the study from 33 hospitals in China from August 2007 to October 2011, inclusive of for 492 males (48.05%) and 532 females (51.95%). The average age was (41.2 ± 12.8) years old. There were 553 cases (54.00%) in left ear, and 471 cases (46.00%) in right ear. The curative effects of different types were shown as follows: the type in low tone frequencies had the highest rate of 90.73%, the type in all frequencies was 82.59%; the type of total deafness was 70.29%; and the type in high tone frequencies had the lowest rate of 65.96%. It had significant difference of the effective rate between different types (χ(2) = 231.58, P = 0.000). Age, time delay before first visit, and severity of initial hearing loss were significantly correlated with hearing improvement. Initial audiogram of SSNHL might predict hearing recovery. The young in age and a short time delay before starting treatment are positive prognostic factors for hearing recovery in SSNHL. The initial severity of hearing loss is negative prognostic factor of hearing recovery.

  14. Sudden infant death syndrome and abnormal metabolism of thiamin.

    Science.gov (United States)

    Lonsdale, Derrick

    2015-12-01

    Although it has been generally accepted that moving the infant from the prone to the supine position has solved the problem of sudden infant death syndrome (SIDS), it has been hypothesized that this is an insufficient explanation and that a mixture of genetic risk, some form of stressful incident and marginal brain metabolism is proportionately required. It is suggested that each of these three variables, with dominance in one or more of them, act together in the common etiology. Much has been written about the association of thiamin and magnesium but the finding of extremely high concentrations of serum thiamin in SIDs victims has largely caused rejection of thiamin as being involved in the etiology. The publication of abnormal brainstem auditory evoked potentials strongly suggests that there are electrochemical changes in the brainstem affecting the mechanisms of automatic breathing and the control of cardiac rhythm. The brainstem, cerebellum and limbic system of the brain are known to be highly sensitive to thiamin deficiency (pseudo-hypoxia) and the pathophysiology is similar to a mild continued deprivation of oxygen. Little attention has been paid to the complex metabolism of thiamin. Dietary thiamin requires the cooperation of the SLC19 family of thiamin transporters for its absorption into cells and recent information has shown that transporter SNPs may be relatively common and can be expected to increase genetic risk. Thiamin must be phosphorylated to synthesize thiamin pyrophosphate (TPP), well established in its vital action in glucose metabolism. TPP is also a cofactor for the enzyme 2-hydroxyacyl-CoA lyase (HACL1) in the peroxisome, emphasizing its importance in alpha oxidation and plasmalogen synthesis in cell membrane physiology. The importance of thiamine triphosphate (TTP) in energy metabolism is still largely unknown. Thiamin metabolism has been implicated in hyperemesis gravidarum and iatrogenic Wernicke encephalopathy has been reported when the

  15. Muscle contributions to elbow joint rotational stiffness in preparation for sudden external arm perturbations.

    Science.gov (United States)

    Holmes, Michael W R; Keir, Peter J

    2014-04-01

    Understanding joint stiffness and stability is beneficial for assessing injury risk. The purpose of this study was to examine joint rotational stiffness for individual muscles contributing to elbow joint stability. Fifteen male participants maintained combinations of three body orientations (standing, supine, sitting) and three hand preloads (no load, solid tube, fluid filled tube) while a device imposed a sudden elbow extension. Elbow angle and activity from nine muscles were inputs to a biomechanical model to determine relative contributions to elbow joint rotational stiffness, reported as percent of total stiffness. A body orientation by preload interaction was evident for most muscles (Pelbow perturbations, found that forearm muscles contribute marginally and showed that orientation and preload should be considered when evaluating elbow joint stiffness and safety.

  16. A comparison of numerical methods for non-Newtonian fluid flows in a sudden expansion

    Science.gov (United States)

    Ilio, G. Di; Chiappini, D.; Bella, G.

    2016-06-01

    A numerical study on incompressible laminar flow in symmetric channel with sudden expansion is conducted. In this work, Newtonian and non-Newtonian fluids are considered, where non-Newtonian fluids are described by the power-law model. Three different computational methods are employed, namely a semi-implicit Chorin projection method (SICPM), an explicit algorithm based on fourth-order Runge-Kutta method (ERKM) and a Lattice Boltzmann method (LBM). The aim of the work is to investigate on the capabilities of the LBM for the solution of complex flows through the comparison with traditional computational methods. In the range of Reynolds number investigated, excellent agreement with the literature results is found. In particular, the LBM is found to be accurate in the prediction of the fluid flow behavior for the problem under consideration.

  17. The Role of Respiratory Infection in Sudden Infant Death Syndrome (SIDS

    Directory of Open Access Journals (Sweden)

    Mage David T.

    2016-06-01

    Full Text Available Introduction: The Sudden Infant Death Syndrome (SIDS is not likely to be explained by a currently measureable presence in all cases and absence in controls, as otherwise it would have been solved already. Indeed, any proposed physiological model for SIDS causation must explain the constant mathematical and statistical properties of SIDS age and gender. We have shown previously that SIDS are characterized by a common 4-parameter lognormal age distribution sparing neonatal infants, by a nominal 50% male excess, and by a higher rate in winter than summer. We test now whether SIDS is closely related to a fulminating prodromal Acute Respiratory Infection (ARI by a common increasing rate with the infants increasing Live Birth Order (LBO, all remaining the same, independent of the change in preferred sleeping positions of the infants, prone or supine.

  18. Sudden sensorineural hearing loss: Is antiviral treatment really necessary?

    Science.gov (United States)

    Övet, Gültekin; Alataş, Necat; Kocacan, Fatma Nur; Gürcüoğlu, Sermin Selver; Görgülü, Hakan; Güzelkara, Fatih; Övet, Habibe

    2015-01-01

    It was aimed to investigate the necessity of antiviral agents in the ISSHL treatment. In this study, the patients, diagnosed with sudden hearing loss and admitted in the first 7 days of hearing loss were divided into two groups; a combination therapy was administered to one of the groups, and famciclovir was administered to the other group as an antiviral treatment in addition to the combined therapy. Both groups were compared in terms of levels of recovery. No statistically significant difference was found in the recovery rates between the two groups (p=0.7). In this study, the additional antiviral treatment was found to have no effect on the remission rates in patients with ISSHL treated with combined therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. A possible explanation of sudden infant death syndrome (SIDS).

    Science.gov (United States)

    Christos, G A; Christos, J A

    1993-09-01

    Research into (lucid) dreaming has shown that the images of a dream are supported by the corresponding body actions, utilizing those muscles which remain active during dreaming. We suggest that Sudden Infant Death Syndrome (SIDS) or Cot Death may be a result of an infant dreaming about its life as a fetus. In the course of that dream, since a fetus does not breathe in the usual sense, the infant may cease to breathe and die. Our hypothesis is consistent with the known facts about SIDS, including social factors such as sleeping position and climatic variation. We suggest that the risk of SIDS can be reduced by making the environment of the infant, as much as possible, unlike that of the womb.

  20. Sudden relaminarisation and lifetimes in forced isotropic turbulence

    Science.gov (United States)

    Linkmann, Moritz; Morozov, Alexander

    2015-11-01

    We demonstrate an unexpected connection between isotropic turbulence and wall-bounded shear flows. We perform direct numerical simulations of isotropic turbulence forced at large scales at moderate Reynolds numbers and observe sudden transitions from chaotic dynamics to a spatially simple flow, analogous to the laminar state in wall bounded shear flows. We find that the survival probabilities of turbulence are exponential and the typical lifetimes increase super-exponentially with the Reynolds number, similar to results on relaminarisation of localised turbulence in pipe and plane Couette flow. Results from simulations subjecting the observed large-scale flow to random perturbations of variable amplitude demonstrate that it is a linearly stable simple exact solution that can be destabilised by a finite-amplitude perturbation, like the Hagen-Poiseuille profile in pipe flow. Our results suggest that both isotropic turbulence and wall-bounded shear flows qualitatively share the same phase-space dynamics.

  1. Voltage transients elicited by sudden step-up of auxin

    Science.gov (United States)

    Pickard, B. G.

    1984-01-01

    It is hypothesized (i) that the molecular mechanism for the reception of friction and flexure and the mechanism by which auxin enhances ethylene production have in common a release of free calcium into the cytosol, (ii) that elevated cytosolic calcium initiates vesicle exocytosis, and (iii) that the vesicles release a factor or set of factors which depolarizes the plasmalemma and promotes ethylene synthesis. One consequence of such exocytosis should be small, extracellularly observable voltage transients. Transients, ranging in size up to 600 microvolts and possessing risetimes (10-90%) of approximately 200 ms, are known to be elicited in etiolated stems of Pisum sativum L. by friction and are here shown to be elicited by sudden increase of auxin concentration and also by a Ca2+ ionophore.

  2. SAPHO syndrome of the temporomandibular joint associated with sudden deafness.

    Science.gov (United States)

    Marsot-Dupuch, K; Doyen, J E; Grauer, W O; de Givry, S C

    1999-05-01

    We report a case of arthritis of the temporomandibular joint (TMJ) associated with sclerosing osteomyelitis of the mandible and temporal bone, causing deafness. The presence of a palmoplantar pustulosis established the diagnosis of SAPHO syndrome. SAPHO (an acronym referring to synovitis, acne, palmoplantar pustulosis, hyperostosis, and osteitis) syndrome is defined by the association of characteristic osteoarticular and dermatologic manifestations, with diffuse sclerosing osteomyelitis of the mandible being a part of this entity. We review the literature of SAPHO syndrome with mandibular manifestations and discuss the mechanisms of inflammatory spread from the TMJ to the cochlea. To our knowledge, this is the first description of skull base involvement in a patient with SAPHO syndrome leading to sudden deafness.

  3. Sudden death due to Eagle syndrome: a case report.

    Science.gov (United States)

    Kumar, Pradeep; Rayamane, Anand P; Subbaramaiah, Mouna

    2013-09-01

    Eagle syndrome represents symptoms manifested by compression of regional structures by elongation of the styloid process or ossification of the stylohyoid membrane. Various theories have been put forward toward the development of Eagle syndrome. Depending on the underlying pathogenetic mechanism and the anatomical structures compressed or irritated by the elongated styloid process, symptoms vary greatly, ranging from cervicofacial pain to cerebral ischemia. Because the symptoms are variable and nonspecific, patients land up in different clinics for treatment. In the present case, the victim had previous episode of unconsciousness along with frequent headache for which she visited various clinics on numerous occasions. The elongated styloid process was appreciated during the postmortem examination, and the diagnosis of sudden death due to mechanical irritation of the carotid sinus by elongated styloid process was made as the sign of acute cardiovascular failure was present and upon exclusion of other causes of death.

  4. [Sudden cardiac death due to sarcoidosis. Case report].

    Science.gov (United States)

    Sejben, István; Som, Zoltán; Cserni, Gábor

    2017-07-01

    Sarcoidosis is a systemic granulomatous disease of unknown aetiology, which is characterized by bilateral hilar lymphadenopathy and pulmonary disease. Clinically detected cardiac involvement occurs in 5% of sarcoid patients, although cardiac manifestations are discovered in 25% of the cases at autopsy. Sarcoid heart disease frequently causes atrioventricular block. The authors present the case of a 44-year-old man with bradycardia. On admission, second degree Mobitz II, then third degree atrioventricular block was diagnosed. Coronarography showed normal coronary arteries. 2.5 years following artificial Biotronik Entovis DR type pacemaker implantation, sudden cardiac death occurred. Autopsy revealed sarcoidosis with cardiac, pulmonary, splenic, renal and lymph node involvement. In case of young or middle-aged patients with atrioventricular block, it is best to search for other causes if the most common coronary origin can be excluded. Orv Hetil. 2017; 158(27): 1067-1070.

  5. Lyme disease: sudden hearing loss as the sole presentation.

    Science.gov (United States)

    Espiney Amaro, C; Montalvão, P; Huins, C; Saraiva, J

    2015-02-01

    Lyme disease is an uncommon tick-borne multisystemic infection caused by Borrelia burgdorferi. The most common clinical manifestation is erythema migrans. In this report, a very unusual presentation of this condition is described, in which sudden onset sensorineural hearing loss was the sole presenting symptom. Case report and review of English-language literature. A patient presented with sensorineural hearing loss, with no other symptoms or signs. Acute Lyme infection was detected by laboratory tests. Magnetic resonance imaging showed signs of labyrinthitis of the same inner ear. After hyperbaric oxygen and systemic antibiotic treatment, the patient showed total hearing recovery, and magnetic resonance imaging showed complete resolution of the labyrinthitis. To our knowledge, this is the first reported case of Lyme disease presenting only with sensorineural hearing loss. Borreliosis should be considered as an aetiological factor in sensorineural hearing loss. Adequate treatment may provide total recovery and prevent more severe forms of Lyme disease.

  6. The role of breastfeeding in sudden infant death syndrome.

    Science.gov (United States)

    McVea, K L; Turner, P D; Peppler, D K

    2000-02-01

    The objective of this article is to review the literature regarding the risk of sudden infant death syndrome (SIDS) in bottle-fed infants compared to those that are breastfed. A meta-analysis and qualitative literature review were performed. Cohort and case-control studies were included if they met a minimum SIDS definition and presented data allowing calculation of an odds ratio (OR). Twenty-three studies were included in the meta-analysis. The studies were heterogeneous, and a majority (14) were of "fair" or "poor" quality. Crude ORs from 19 individual studies favored breastfeeding as protective against SIDS. The combined analysis indicated that bottle-fed infants were twice as likely to die from SIDS (pooled OR = 2.11; 95% CI 1.66-2.68). The results of the analysis show that there is an association between bottle-feeding and SIDS, but this may be related to confounding variables.

  7. [Sudden cardiac death during a city marathon run].

    Science.gov (United States)

    Beutler, J; Schmid, E; Fischer, S; Hürlimann, S; Konrad, C

    2015-06-01

    Sudden cardiac death (SCD) in young athletes during physical stress is a rare event with an incidence of 1-3 deaths per 100,000 athletes per year. A coronary anomaly is the second most common cause of death following hypertrophic cardiomyopathy. Symptomatic prodromes occur in 20% of cases prior to the SCD event. This case report describes a 35-year-old male who collapsed near the finishing line of a half marathon run. Despite immediate resuscitation attempts and initial return of spontaneous circulation (ROSC), a pulseless electrical activity (PEA) followed and the patient died 1 h after arrival in the resuscitation unit. The autopsy revealed an anomalous left coronary artery (ALCA), which can lead to ischemia of the respective heart muscles under severe stress.

  8. Sudden Chain Energy Transfer Events in Vibrated Granular Media

    Science.gov (United States)

    Rivas, Nicolás; Ponce, Suomi; Soto, Rodrigo; Cordero, Patricio; Mujica, Nicolás; Risso, Dino; Gallet, Basille

    2012-02-01

    In a mixture of two species of grains of equal size but different mass, placed in a vertically vibrated shallow box, there is spontaneous segregation. Once the system is at least partly segregated and clusters of the heavy particles have formed, there are sudden peaks of the horizontal kinetic energy of the heavy particles, that is otherwise small. Together with the energy peaks the clusters rapidly expand and the segregation is partially lost. The process repeats once segregation has taken place again, either randomly or with some regularity in time depending on the experimental or numerical parameters. An explanation for these events is provided based on the existence of a fixed point for an isolated particle bouncing with only vertical motion. The horizontal energy peaks occur when the energy stored in the vertical motion is partly transferred into horizontal energy through a chain reaction of collisions between heavy particles.

  9. Genotyping of Clostridium perfringens associated with sudden death in cattle

    Directory of Open Access Journals (Sweden)

    S Miyashiro

    2009-01-01

    Full Text Available Toxigenic types of Clostridium perfringens are significant causative agents of enteric disease in domestic animals, although type E is presumably rare, appearing as an uncommon cause of enterotoxemia of lambs, calves and rabbits. We report herein the typing of 23 C. perfringens strains, by the polymerase chain reaction (PCR technique, isolated from small intestine samples of bovines that have died suddenly, after manifesting or not enteric or neurological disorders. Two strains (8.7% were identified as type E, two (8.7% as type D and the remainder as type A (82.6%. Commercial toxoids available in Brazil have no label claims for efficacy against type E-associated enteritis; however, the present study shows the occurrence of this infection. Furthermore, there are no recent reports on Clostridium perfringens typing in the country.

  10. Mutations in calmodulin cause ventricular tachycardia and sudden cardiac death

    DEFF Research Database (Denmark)

    Nyegaard, Mette; Overgaard, Michael Toft; Søndergaard, Mads

    2012-01-01

    a substantial part of sudden cardiac deaths in young individuals. Mutations in RYR2, encoding the cardiac sarcoplasmic calcium channel, have been identified as causative in approximately half of all dominantly inherited CPVT cases. Applying a genome-wide linkage analysis in a large Swedish family with a severe...... dominantly inherited form of CPVT-like arrhythmias, we mapped the disease locus to chromosome 14q31-32. Sequencing CALM1 encoding calmodulin revealed a heterozygous missense mutation (c.161A>T [p.Asn53Ile]) segregating with the disease. A second, de novo, missense mutation (c.293A>G [p.Asn97Ser......]) was subsequently identified in an individual of Iraqi origin; this individual was diagnosed with CPVT from a screening of 61 arrhythmia samples with no identified RYR2 mutations. Both CALM1 substitutions demonstrated compromised calcium binding, and p.Asn97Ser displayed an aberrant interaction with the RYR2...

  11. Aortoiliac occlusive disease presenting as sudden onset paraplegia.

    Science.gov (United States)

    Lai, Chien-Hung; Wang, Cheng-Hsien; Wu, Shih-Yun; Shih, Hong-Mo

    2014-07-01

    Thromboembolism and atherosclerotic stenosis both can cause arterial occlusion. Aortoiliac occlusive disease involving bifurcation of the aortoiliac artery induces symptoms of ischemia such as claudication and pain of buttocks and thighs, decreased bilateral femoral pulses, and impotence. Here, we describe a 58-year-old woman with a past history of atrial fibrillation and lacuna stroke with minimal right side weakness. She presented to our emergency department with sudden onset bilateral pain in the legs and paraplegia. A comprehensive examination revealed paresthesia and decreasing bilateral distal pulses. Computed tomographic imaging showed filling defects over the low abdominal aorta just above the bifurcation of the common iliac artery and bilateral femoral arteries. Acute aortic embolic occlusion was suspected. Her symptoms were resolved after emergent thrombectomy for acute limb ischemia. Physicians need to be aware of aortoiliac embolic occlusive disease which may present as acute paraplegia.

  12. A review of patients who suddenly deteriorate in the presence of paramedics

    Directory of Open Access Journals (Sweden)

    Archer Frank

    2008-07-01

    Full Text Available Abstract Background The report of the Ministerial Review of Trauma and Emergency Services in Victoria, Australia, recommended that paramedics be permitted to divert to the closest hospital in incidences of life threatening situations prior to and during transport. An audit of patients that suddenly deteriorated in paramedic care was recommended by the Ministerial Review. The objective of the study was to identify the number and outcome of patients who suddenly deteriorated in the presence of paramedics. Methods A retrospective cohort study of trauma patients who suddenly deteriorated in the presence of paramedics during 2002. As there was no standard definition, sudden deterioration was defined using a predetermined set of physiological criteria. Patient care record data of patients who suddenly deteriorated were compared with the State Trauma Registry to determine those who sustained hospital defined major trauma. Patient care records where hospital bypass was undertaken were identified and analysed. Ethics committee approval was obtained. Results There were 2,893 patients that suddenly deteriorated according to predefined criteria. 2,687 (5.1% of the total trauma patients for 2002 were suitable for further analysis. The majority of patients had a sudden decrease in BP (n = 2,463 with 4.3% having hospital defined major trauma. For patients with a sudden decrease in conscious state or a total GCS score of less than 13 (n = 77, 37.7% had hospital defined major trauma; and a sudden increase/decrease in pulse rate and sudden decrease in BP (n = 65, 26.2% had hospital defined major trauma. Only 28 documented incidents of hospital bypass were identified. Conclusion This study suggests that the incidents of patients suddenly deteriorating in the presence of paramedics are low and the incidence of hospital bypass is not well documented.

  13. Resistance coefficient during ice slurry flow through pipe sudden constriction

    Directory of Open Access Journals (Sweden)

    Ł. Mika

    2010-07-01

    Full Text Available Due to the adverse environmental effects of some commonly-used refrigerants, efforts are still underway to find new cooling mediumsthat would be safer to the ozone layer and would not increase the greenhouse effect. Ice slurry as a new ecological coolant suits theprocesses requiring the preservation of constant and equal temperature in the cooling process of the full section of the cooled solid. Thanks to that, ice slurry can find a wide potential application in such branches of industry, as heat treatment, materials engineering, or foundry. In this paper, flow systems which are commonly used in fittings elements such as diameter’s reductions in ice slurry pipelines, are experimentally investigated. In the study reported in this paper, the consideration was given to the specific features of the slurry flow in which the flow qualities depend mainly on the volume fraction of solid particles. The results of the experimental studies on the flow resistance, presented herein, enabled to determine the resistance coefficient during the ice slurry flow through the pipe sudden constriction. The volume fraction of solid particles in the slurry ranged from 5 to 30%. The recommended and non-recommended range of the Reynolds number for the ice slurry flow through the pipe sudden constriction were presented in this paper. The experimental studies were conducted on a few variants of the most common reductions of copper pipes. Further studies on the determination of the resistance coefficient in the remaining fittings elements of the pipeline were recommended in the paper as well as the further theoretical studies intended to determine the theoretical relations to calculate the resistance coefficient in all the fittings elements in the pipeline (on the basis of the experimental studies and to elaborate the calculation pattern of the entire ice slurry system.

  14. Sudden unexpected death in epilepsy: Evaluation of forensic autopsy cases.

    Science.gov (United States)

    Zhuo, Luo; Zhang, Yang; Zielke, H Ronald; Levine, Barry; Zhang, Xiang; Chang, Lin; Fowler, David; Li, Ling

    2012-11-30

    Epilepsy is a common chronic neurological disorder characterized by seizures. Mortality is significantly increased in patients with epilepsy. Sudden unexpected death in epilepsy (SUDEP) is the most common seizure-related category of death. A retrospective study of forensic autopsy cases from 2007 to 2009 at the Office of the Chief Medical Examiner (OCME) yielded a total of 104 sudden unexpected deaths directly or indirectly caused by an epilepsy/seizure disorder in the State of Maryland. Of these deaths, 74 cases met a general accepted definition of SUDEP. The age of SUDEP individuals ranged from 14 to 63 with the majority of subjects in the ages between 21 and 50 years (58 cases, 78.4%). Males were slightly more likely than females to die of SUDEP (male:female=1.5:1 based on the rate). The onset age of epilepsy was documented in 47.3% of cases (35/74) based on investigation and medical records. Of the 35 cases, 12 subjects had early onset epilepsy (onset ages 1-15 years) and 20 subjects had duration of epilepsy for more than 10 years. The majority of deaths (61 of the 74 cases, 82.4%) were unwitnessed. Death scene investigation showed that 71 deaths (95.9%) occurred inside their residence with 50 subjects (70.4%) found either in bed or on the bedroom floor near the bed. Forty-three out of 74 cases (58.1%) showed neuropathological lesions. Per history, 50 subjects were reported as being on anti-epileptic drugs (AEDs). However, postmortem toxicological analysis revealed that only 26 subjects (35.1%) had detectable AEDs. Of the 74 cases, seizure disorder or epilepsy was listed as primary cause of death in 66 cases and the term of SUDEP as official cause of death in only 8 cases. This report focuses on the characteristics of death scene investigation and postmortem examination findings of SUDEP cases.

  15. Effectiveness of intratympanic dexamethasone for refractory sudden sensorineural hearing loss.

    Science.gov (United States)

    Erdur, Omer; Kayhan, Fatma Tulin; Cirik, Ahmet Adnan

    2014-06-01

    The purpose of this study was to investigate the effectiveness of intratympanic steroids in patients with idiopathic sudden sensorineural hearing loss who did not respond to initial systemic steroid therapy. This retrospective study involved 51 patients, who did not respond to systemic steroids as a first-line treatment. Initial systemic steroid therapy consisted of administration of methylprednisolon intravenously (250 mg) at the first day and followed by orally (1 mg/kg) tapering for 14 days. Twenty-one patients accepted intratympanic treatment, and the remaining 30 patients who refused intratympanic treatment were evaluated as the control group. Steroids (dexamethasone drops, 1 mg/mL) were administered through a ventilation tube. Hearing was assessed immediately before treatment and 2 months after treatment. Recovery of hearing was defined as an improvement of >20 dB in the pure tone average. We tested 250, 500, 1,000, 2,000, 4,000, and 8,000 Hz frequencies for the pure tone audiometric evaluation. Statistically Student's t test, Mann-Whitney U test, Chi-squared and Fisher's exact tests were used. The pure tone average improved in 47.6% of the intratympanic group and in 10% of the control group (p = 0.002), with pure tone average improvements of 19.9 ± 16.5 and 4.76 ± 9.6 dB in the intratympanic and control groups, respectively. When the hearing threshold at each frequency was analyzed, improvements at all frequencies were significantly greater in the intratympanic steroid group when compared with the control group (p sudden sensorineural hearing loss in patients, who are refractory to primary systemic steroid therapy.

  16. Tympanotomy and sealing of the round window for treatment of sudden deafness

    DEFF Research Database (Denmark)

    Ul-Mulk, Jamshaid; Friis, Søren; Hahn, Christoffer Holst

    2011-01-01

    The objective of this study was to evaluate the effectiveness of explorative tympanotomy and sealing of the round window in patients diagnosed with sudden deafness.......The objective of this study was to evaluate the effectiveness of explorative tympanotomy and sealing of the round window in patients diagnosed with sudden deafness....

  17. Sudden cardiac arrest as a presentation of Brugada syndrome unmasked by thyroid storm

    NARCIS (Netherlands)

    Korte, Anna K M; Derde, Lennie; van Wijk, Jeroen; Tjan, David H

    2015-01-01

    An 18-year-old man suffered a sudden cardiac arrest with ventricular fibrillation and was successfully resuscitated. He had neither a medical nor family history of cardiac disease/sudden death, but was known to have Graves' disease, for which he was treated with radioactive iodine. Recently, block-a

  18. Cognitive Changes, Critical Sessions, and Sudden Gains in Cognitive-Behavioral Therapy for Depression

    Science.gov (United States)

    Tang, Tony Z.; DeRubeis, Robert J.; Beberman, Rachel; Pham, Thu

    2005-01-01

    Using an independent cognitive-behavioral therapy (CBT) data set, the authors replicated T. Z. Tang and R. J. DeRubeis' (1999) discovery of sudden gains--sudden and large decreases in depression severity in a single between-session interval. By incorporating therapy session transcripts, the authors of this study improved the reliability of the…

  19. Sudden unexplained death: Heritability and diagnostic yield of cardiological and genetic examination in surviving relatives

    NARCIS (Netherlands)

    Tan, Hanno L.; Hofman, Nynke; Van Langen, Irene M.; Van Der Wal, Allard C.; Wilde, Arthur A. M.

    2005-01-01

    Background-Sudden death mostly follows from cardiac disorders that elicit lethal ventricular arrhythmias. In young individuals, it often remains unexplained because history and/or postmortem analysis are absent or provide no clue. Because such sudden unexplained deaths (SUDs) may have heritable caus

  20. Primary prophylaxis of sudden death in hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, and dilated cardiomyopathy.

    Science.gov (United States)

    Klein, George J; Krahn, Andrew D; Skanes, Allan C; Yee, Raymond; Gula, Lorne J

    2005-09-01

    We present an evidence-based overview of primary prevention of sudden cardiac death. Several recent studies have provided important data regarding pharmacologic and device-based therapy for patients with conditions that confer high risk for sudden death. A rational approach to these therapies, with emphasis on implanted cardiovertor defibrillators, is discussed.

  1. Recreational soccer can improve the reflex response to sudden trunk loading among untrained women

    DEFF Research Database (Denmark)

    Pedersen, Mogens Theisen; Randers, Morten Bredsgaard; Skotte, Jørgen H.

    2009-01-01

    assignment was blinded to the test personnel. Physical education students organized the training. During 1 hour of soccer training, the total number of sudden moves including sudden loading of the upper body (e.g. turns, stops, throw-ins, headers, and shoulder tackles) was 192 (63). In SO, time elapsed until...

  2. Sudden Gains during Psychological Treatments of Anxiety and Depression: A Meta-Analysis

    Science.gov (United States)

    Aderka, Idan M.; Nickerson, Angela; Boe, Hans Jakob; Hofmann, Stefan G.

    2012-01-01

    Objective: The present study quantitatively reviewed the literature on sudden gains in psychological treatments for anxiety and depression. The authors examined the short- and long-term effects of sudden gains on treatment outcome as well as moderators of these effects. Method: The authors conducted a literature search using PubMed, PsycINFO, the…

  3. Sudden Gains during Psychological Treatments of Anxiety and Depression: A Meta-Analysis

    Science.gov (United States)

    Aderka, Idan M.; Nickerson, Angela; Boe, Hans Jakob; Hofmann, Stefan G.

    2012-01-01

    Objective: The present study quantitatively reviewed the literature on sudden gains in psychological treatments for anxiety and depression. The authors examined the short- and long-term effects of sudden gains on treatment outcome as well as moderators of these effects. Method: The authors conducted a literature search using PubMed, PsycINFO, the…

  4. Cognitive Changes, Critical Sessions, and Sudden Gains in Cognitive-Behavioral Therapy for Depression

    Science.gov (United States)

    Tang, Tony Z.; DeRubeis, Robert J.; Beberman, Rachel; Pham, Thu

    2005-01-01

    Using an independent cognitive-behavioral therapy (CBT) data set, the authors replicated T. Z. Tang and R. J. DeRubeis' (1999) discovery of sudden gains--sudden and large decreases in depression severity in a single between-session interval. By incorporating therapy session transcripts, the authors of this study improved the reliability of the…

  5. Cardiac symptoms before sudden cardiac death caused by coronary artery disease

    DEFF Research Database (Denmark)

    Jabbari, Reza; Risgaard, Bjarke; Holst, Anders G;

    2013-01-01

    The aim of this nationwide case-control study was to identify and characterise symptoms before sudden death of young persons who had died due to coronary artery disease (CAD).......The aim of this nationwide case-control study was to identify and characterise symptoms before sudden death of young persons who had died due to coronary artery disease (CAD)....

  6. Sudden deafness in vertebrobasilar ischemia: clinical features, vascular topographical patterns and long-term outcome.

    Science.gov (United States)

    Lee, Hyung; Baloh, Robert W

    2005-01-15

    The aim of this study is to document the clinical features and natural history of sudden deafness associated with vertebrobasilar ischemia (VBI) and to describe the vascular topographic patterns of ischemic lesions on brain MRI associated with sudden deafness based on data collected from a prospective acute stroke registry. From 364 consecutive cases of VBI diagnosed by clinical features and brain MRI between January 2000 and September 2003, 29 patients were identified as having sudden deafness as a symptom of VBI. In our series, the incidence of sudden deafness following VBI is 8.0% (29/364). Hearing loss occurred unilaterally (n=27) or bilaterally (n=2). All but one had vertigo as an associated symptom. Nine patients (31%) presented with an isolated audiovestibular loss initially and subsequently had delayed neurological deficits. Nearly a half of patients (14/29: 48%) showed cochlear features of hearing loss. Seventeen (81%) of 21 patients who were followed for at least 1 year after onset of sudden deafness had a recovery of hearing partially (n=10) or completely (n=7). The improvement rate of hearing loss in patients with profound hearing loss was significantly lower than that in patients with less than profound hearing loss (40% vs. 89%, Psudden deafness. An isolated sudden deafness with cochlear audiometric features can be the initial presentation of VBI. Sudden deafness due to VBI often has a good outcome. There is topographic heterogeneity of ischemic lesions on brain MRI in patients with sudden deafness due to VBI.

  7. Sudden cardiac arrest as a presentation of Brugada syndrome unmasked by thyroid storm

    NARCIS (Netherlands)

    Korte, Anna K M; Derde, Lennie; van Wijk, Jeroen; Tjan, David H

    2015-01-01

    An 18-year-old man suffered a sudden cardiac arrest with ventricular fibrillation and was successfully resuscitated. He had neither a medical nor family history of cardiac disease/sudden death, but was known to have Graves' disease, for which he was treated with radioactive iodine. Recently,

  8. Sudden death in patients with myocardial infarction and left ventricular dysfunction, heart failure, or both

    DEFF Research Database (Denmark)

    Solomon, Scott D; Zelenkofske, Steve; McMurray, John J V

    2005-01-01

    BACKGROUND: The risk of sudden death from cardiac causes is increased among survivors of acute myocardial infarction with reduced left ventricular systolic function. We assessed the risk and time course of sudden death in high-risk patients after myocardial infarction. METHODS: We studied 14,609 ...

  9. THREE-DIMENSIONAL NUMERICAL SIMULATION OF AERATED FLOWS DOWNSTREAM SUDDEN FALL AERATOR EXPANSION-IN A TUNNEL

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-min; CHEN Jian-gang; XU Wei-lin; WANG Yu-rong; LI Gui-ji

    2011-01-01

    Air entrainment is known to be one of efficient and inexpensive methods to prevent cavitation damages in hydropower projects.The shape of sudden expansion-fall is used as a common device for mitigating cavitation erosions.The complex flow patterns with cavitation are numerically simulated by using the realizable k-ε turbulence model and the air-water mixture model.The calculated results are compared well with the experimental results as well as those obtained with the k -ε turbulence model with the Volume Of Fluid (VOF) Model.The calculated results agree well with the experimental data for the aeration cavity and wall pressure.Moreover, the air concentration near sidewall is simulated by a mixture model.It is found that the mixture turbulence model is superior to the VOF turbulence model.

  10. Back muscle response to sudden trunk loading can be modified by training among healthcare workers

    DEFF Research Database (Denmark)

    Pedersen, Mogens Theisen; Essendrop, Morten; Skotte, Jørgen H.

    2007-01-01

    . Available data suggest that a delayed muscle reflex response to sudden trunk loading may increase the risk of low back injuries. We have previously shown that training may alter the response to sudden trunk loading in healthy subjects and decrease the time elapsed until stopping of the forward movement...... of the trunk (stopping time). Data on the possibilities of a training-induced improvement in the reflex response among workers exposed to sudden trunk loading on the job are, however, nonexistent, and there is no evidence of long-term benefits, i.e., the sustainability of a positive training effect. Methods......Study Design. Experimental study of the effect of physical training on the reaction to sudden back loading. Objective. To investigate the effect and sustainability of "on the job training" on the reaction to sudden back loading among employees at a geriatric ward. Summary of Background Data...

  11. Sudden infant death syndrome, childhood thrombosis, and presence of genetic risk factors for thrombosis

    DEFF Research Database (Denmark)

    Larsen, T B; Nørgaard-Pedersen, B; Banner, Jytte

    2000-01-01

    in the child. This prompted us to investigate these genetic markers of thromboembolic disease in 121 cases of sudden infant death syndrome and in relevant controls, in the expectation of a more frequent occurrence of these markers if thrombosis is an etiological factor in sudden infant death syndrome......Sudden infant death syndrome or "cot death" has until the late eighties been a significant cause of death in children between the ages of 1 month and 1 year. Approximately two per 1000 children born alive dies of sudden infant death syndrome each year in Western Europe, North America, and Australia....... The vulnerability of the infant brain stem to ischemia has been suggested to be a conceivable cause of sudden infant death syndrome. This is compatible with a hypothesis that genetic risk factors for cerebral thrombosis could cause microinfarction in the brain stem during the first month of life, affecting vital...

  12. [Sudden death of a young man as late sequelae complicating a pediatric disease: About a case].

    Science.gov (United States)

    Pierry, Clémence; Franchet, Camille; Tuchtan-Torrents, Lucile; Macon, Céline; Torrents, Julia; Capuani, Caroline; Piercecchi-Marti, Marie-Dominique

    2017-04-01

    In France, sudden death is responsible every year for 40,000 deaths. The most frequent etiology is cardiac disease. Atheromatous-related pathology is the most common etiology beyond 35, but cardiomyopathies and channelopathies are responsible for a significant number of deaths in young adults. Some acquired disorders can also cause sudden cardiac death. We report the case of a 17-year-old man who died suddenly after sport. Autopsy and pathological study found multiple giant coronary aneurysms. Thrombosis and fibrous scar of myocardial ischemic events were observed. These lesions were in favor of late sequelae of Kawasaki disease. Kawasaki disease is a rare but not exceptional cause of sudden cardiac death in young adults. In the lack of known clinical history, some aspects, even not specific, should evoke this diagnosis. Even in front of apparent good clinical tolerance, these sequelae require appropriate follow-up because of a significant risk of sudden death.

  13. SUDDEN UNEXPLAINED JUVENILE DEATH AND THE ROLE OF MEDICOLEGAL INVESTIGATION: UPDATE ON MOLECULAR AUTOPSY

    Directory of Open Access Journals (Sweden)

    Antonina Argo

    2012-04-01

    Full Text Available In the past few years, contributions of molecular biology assays to the investigation of sudden juvenile death have permitted to clarify some of the pathogenetic aspects of sudden arrhythmic death, opening the way to preventive action on victims’ relatives. We reviewed literature on the genetics of sudden juvenile death, and on molecular biology assays performed on autoptic samples. Biological investigation permits the detection of genetic mutations underlying the susceptibility to sudden cardiac death of individuals with rare inherited forms of arrhythmia (Long QT Syndrome, Brugada Syndrome, Lev’s disease etc. through the analysis of critical sequences codifying for ion channel subunits (HERG, KvLQT1, MinK, Mirp1, SCN5A, KCNQ1, KCNH2, KCNE1, KCNE2. The main objective of post-mortem investigation in sudden juvenile death is the detection of treatable monogenic inherited disorders, in order to prevent further deaths among the relatives of the deceased patient.

  14. Sudden infant death syndrome, childhood thrombosis, and presence of genetic risk factors for thrombosis

    DEFF Research Database (Denmark)

    Larsen, TB; Nørgaard-Pedersen, B; Lundemose, JB

    2000-01-01

    . The vulnerability of the infant brain stem to ischemia has been suggested to be a conceivable cause of sudden infant death syndrome. This is compatible with a hypothesis that genetic risk factors for cerebral thrombosis could cause microinfarction in the brain stem during the first month of life, affecting vital......Sudden infant death syndrome or "cot death" has until the late eighties been a significant cause of death in children between the ages of 1 month and 1 year. Approximately two per 1000 children born alive dies of sudden infant death syndrome each year in Western Europe, North America, and Australia...... in the child. This prompted us to investigate these genetic markers of thromboembolic disease in 121 cases of sudden infant death syndrome and in relevant controls, in the expectation of a more frequent occurrence of these markers if thrombosis is an etiological factor in sudden infant death syndrome...

  15. Factors Prognostic of Season-Associated Sudden Sensorineural Hearing Loss: A Retrospective Observational Study

    Science.gov (United States)

    Ryu, In Yong; Park, Sang Hyun; Park, Eun Bin; Kim, Ho Joong; Kim, Sang Hoon

    2017-01-01

    Background and Objectives This study examined whether the prognosis of sudden deafness was dependent on the time of onset and evaluated the factors affecting prognosis during each period. Subjects and Methods Patients who developed sudden hearing loss from January 2005 to December 2015 were evaluated retrospectively. Meteorological data were obtained from the official website of the Korea Meteorological Administration. Factors prognostic of hearing recovery rate were analyzed. Results The hearing recovery rate of the 318 patients who developed sudden deafness did not differ significantly by month. Mean temperature and daily temperature range at onset of sudden deafness were not associated with recovery rate. Conclusions The recovery rate in patients with sudden deafness did not differ markedly by season. PMID:28417108

  16. 二代改进型核电厂严重事故下一回路卸压时机敏感性研究%Sensitivity Analysis on Time of Reactor Coolant System Depressurization under Severe Accident for Generation II+ Nuclear Power Plants

    Institute of Scientific and Technical Information of China (English)

    种毅敏; 杨志义; 石雪垚; 张佳佳; 李春; 倪曼; 徐雨婷

    2015-01-01

    Reactor coolant system (RCS)depressurization is necessary measure for nuclear power plant to mitigate the severe accident,as well as a significant part of the severe accident management guidelines (SAMG).Difference may exist on the time of RCS depressurization in different NPPs.In this paper,based on MAAP4,the sensitivity analysis of time to implement RCS depressurization is performed.A typical integrated computer program,and different effects on mitigation of severe accident are compared.The simulation scenario is typical drill situation of generation II + NPPs,and conclusions can be reference for similar NPPs to implement severe accident management strategy.%一回路卸压是核电厂缓解严重事故的必要手段,也是严重事故管理导则(SAMG)的重要内容,国内核电厂严重事故管理中对一回路卸压的要求并不相同,本文基于典型二代改进型核电厂 SAMG 演练的场景,使用一体化计算程序 MAAP4,对一回路卸压时机进行敏感性分析,比较不同卸压时机对缓解严重事故效果的影响,所给出的结论可为相同类型核电厂制定严重事故管理策略时提供参考。

  17. Association between resting heart rate and coronary artery disease, stroke, sudden death and noncardiovascular diseases: a meta-analysis

    Science.gov (United States)

    Zhang, Dongfeng; Wang, Weijing; Li, Fang

    2016-01-01

    Background: Resting heart rate is linked to risk of coronary artery disease, stroke, sudden death and noncardiovascular diseases. We conducted a meta-analysis to assess these associations in general populations and in populations of patients with hypertension or diabetes mellitus. Methods: We searched PubMed, Embase and MEDLINE from inception to Mar. 5, 2016. We used a random-effects model to combine study-specific relative risks (RRs). We used restricted cubic splines to assess the dose–response relation. Results: We included 45 nonrandomized prospective cohort studies in the meta-analysis. The multivariable adjusted RR with an increment of 10 beats/min in resting heart rate was 1.12 (95% confidence interval [CI] 1.09–1.14) for coronary artery disease, 1.05 (95% CI 1.01–1.08) for stroke, 1.12 (95% CI 1.02–1.24) for sudden death, 1.16 (95% CI 1.12–1.21) for noncardiovascular diseases, 1.09 (95% CI 1.06–1.12) for all types of cancer and 1.25 (95% CI 1.17–1.34) for noncardiovascular diseases excluding cancer. All of these relations were linear. In an analysis by category of resting heart rate ( 80 beats/min), the RRs were 0.99 (95% CI 0.93–1.04), 1.08 (95% CI 1.01–1.16) and 1.30 (95% CI 1.19–1.43), respectively, for coronary artery disease; 1.08 (95% CI 0.98–1.19), 1.11 (95% CI 0.98–1.25) and 1.08 (95% CI 0.93–1.25), respectively, for stroke; and 1.17 (95% CI 0.94–1.46), 1.31 (95% CI 1.12–1.54) and 1.57 (95% CI 1.39–1.77), respectively, for noncardiovascular diseases. After excluding studies involving patients with hypertension or diabetes, we obtained similar results for coronary artery disease, stroke and noncardiovascular diseases, but found no association with sudden death. Interpretation: Resting heart rate was an independent predictor of coronary artery disease, stroke, sudden death and noncardiovascular diseases over all of the studies combined. When the analysis included only studies concerning general populations, resting

  18. On the composite response of the MLT to major sudden stratospheric warming events with elevated stratopause

    Science.gov (United States)

    Limpasuvan, Varavut; Orsolini, Yvan J.; Chandran, Amal; Garcia, Rolando R.; Smith, Anne K.

    2016-05-01

    Based on a climate-chemistry model (constrained by reanalyses below ~50 km), the zonal-mean composite response of the mesosphere and lower thermosphere (MLT) to major sudden stratospheric warming events with elevated stratopauses demonstrates the role of planetary waves (PWs) in driving the mean circulation in the presence of gravity waves (GWs), helping the polar vortex recover and communicating the sudden stratospheric warming (SSW) impact across the equator. With the SSW onset, strong westward PW drag appears above 80 km primarily from the dissipation of wave number 1 perturbations with westward period of 5-12 days, generated from below by the unstable westward polar stratospheric jet that develops as a result of the SSW. The filtering effect of this jet also allows eastward propagating GWs to saturate in the winter MLT, providing eastward drag that promotes winter polar mesospheric cooling. The dominant PW forcing translates to a net westward drag above the eastward mesospheric jet, which initiates downwelling over the winter pole. As the eastward polar stratospheric jet returns, this westward PW drag persists above 80 km and acts synergistically with the return of westward GW drag to drive a stronger polar downwelling that warms the pole adiabatically and helps reform the stratopause at an elevated altitude. With the polar wind reversal during the SSW onset, the westward drag by the quasi-stationary PW in the winter stratosphere drives an anomalous equatorial upwelling and cooling that enhance tropical stratospheric ozone. Along with equatorial wind anomalies, this ozone enhancement subsequently amplifies the migrating semidiurnal tide amplitude in the winter midlatitudes.

  19. Infant pacifiers for reduction in risk of sudden infant death syndrome.

    Science.gov (United States)

    Psaila, Kim; Foster, Jann P; Pulbrook, Neil; Jeffery, Heather E

    2017-04-05

    Sudden infant death syndrome (SIDS) has been most recently defined as the sudden unexpected death of an infant less than one year of age, with onset of the fatal episode apparently occurring during sleep, that remains unexplained after a thorough investigation, including the performance of a complete autopsy and a review of the circumstances of death and clinical history. Despite the success of several prevention campaigns, SIDS remains a leading cause of infant mortality. In 1994, a 'triple risk model' for SIDS was proposed that described SIDS as an event that results from the intersection of three factors: a vulnerable infant; a critical development period in homeostatic control (age related); and an exogenous stressor. The association between pacifier (dummy) use and reduced incidence of SIDS has been shown in epidemiological studies since the early 1990s. Pacifier use, given its low cost, might be a cost-effective intervention for SIDS prevention if it is confirmed effective in randomised controlled trials. To determine whether the use of pacifiers during sleep versus no pacifier during sleep reduces the risk of SIDS. We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 2), MEDLINE via PubMed, Embase, and CINAHL to 16 March 2016. We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. Published and unpublished controlled trials using random and quasi-random allocations of infants born at term and at preterm (less than 37 weeks' gestation) or with low birth weight (searches. We found no eligible studies. We identified no randomised controlled trials examining infant pacifiers for reduction in risk of SIDS. We found no randomised control trial evidence on which to support or refute the use of pacifiers for the prevention of SIDS.

  20. Depressurization of a spread of Brazil-Bolivia gas pipeline and the emergency repair of a weld crack in a instrument derivation at Campo Grande compression station; Despressurizacao de trecho do gasoduto Bolivia-Brazil para reparo emergencial de trinca em uma derivacao de instrumento de temperatura na Estacao de Compressao de Campo Grande - MS

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, Carlos Ribeiro; Leite Junior, Ismael Casano [TBG - Transportadora Brasileira Gasoduto Bolivia Brasil S.A., Rio de Janeiro, RJ (Brazil)

    2005-07-01

    The purpose of this paper is to report the actions taken to repair a gas leak, at an original pressure of 100 kgf/cm{sup 2}, occurred due to a 1 1/2'' branch pipe weld crack, located on the 24'' Campo Grande - Mato Grosso do Sul Compression Station discharge pipe. This branch pipe was used to a thermo well installation and was submitted to an additional strength caused by thermo well vibration. The weld repair actions required an urgent depressurization of a 33 km spread of Bolivia-Brazil Pipeline in a timely manner, to avoid any negative impact in the operational schedule. (author)

  1. Simultaneous idiopathic bilateral sudden hearing loss - characteristics and response to treatment.

    Science.gov (United States)

    Akil, Ferit; Yollu, Umur; Yilmaz, Mehmet; Yener, H Murat; Mamanov, Marlen; Inci, Ender

    2017-01-24

    The aetiology of sudden hearing loss is poorly defined; however, infectious, vascular and neoplastic aetiologies are presumed to be responsible. In addition, the aetiology of bilateral sudden hearing loss is also unknown. The objective of this study is identify the characteristics and treatment response of simultaneous bilateral sudden hearing loss. This is a case-control study that practised in tertiary care academic centre. 132 patients with sudden hearing loss who were treated with systemic steroid and hyperbaric oxygen together were included. 26 patients had bilateral sudden hearing loss and 106 patients had unilateral sudden hearing loss. Patients were evaluated with clinical, audiological and radiological examinations and laboratory tests were done. Findings and response to treatment of the patients were compared. The mean ages of patients with unilateral and bilateral sudden hearing loss were 42.0 years and 24.5 years respectively with a statistically significant difference (psudden hearing loss. Pre-treatment audiologic thresholds were 69.1dB for unilateral sudden hearing loss and 63.3dB for the left ears and 67.6dB for the right ears for bilateral sudden hearing loss without significant difference. Post-treatment average hearing threshold in unilateral sudden hearing loss was 47.0dB and 55.4dB for the left ears and 59.0 for the right ears in bilateral sudden hearing loss. Average hearing improvement in unilateral sudden hearing loss group was significant (psudden hearing loss group for both ears. Between the groups; there was a significant difference for hearing improvement favouring unilateral sudden hearing loss (psudden hearing loss showed lower age, worse prognosis and higher rate of positive immune response markers. Cardiovascular risk factors seem to have an important role in the aetiology of unilateral cases whereas this importance was not present in bilateral ones. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia C

  2. Sudden cardiac death and inherited channelopathy: the basic electrophysiology of the myocyte and myocardium in ion channel disease.

    Science.gov (United States)

    Martin, Claire A; Matthews, Gareth D K; Huang, Christopher L-H

    2012-04-01

    Mutations involving cardiac ion channels result in abnormal action potential formation or propagation, leading to cardiac arrhythmias. Despite the large impact on society of sudden cardiac death resulting from such arrhythmias, understanding of the underlying cellular mechanism is poor and clinical risk stratification and treatment consequently limited. Basic research using molecular techniques, as well as animal models, has proved extremely useful in improving our knowledge of inherited arrhythmogenic syndromes. This offers the practitioner tools to accurately diagnose rare disorders and provides novel markers for risk assessment and a basis for new strategies of treatment.

  3. Oxygen transfer characteristics of water and bubble mixture pipe flow through two sudden contractions and expansions

    Institute of Scientific and Technical Information of China (English)

    尹则高; 解绍华; 程东升; 龙翔宇

    2014-01-01

    The dissolved oxygen (DO) concentration is an important index of water quality. This paper studies the dissolved oxygen recovery of the water and bubble mixture pipe flow through two sudden contractions and expansions. A 3-D computational fluid dy- namics model is established to simulate the water and bubble mixture flow with a DO transport model. An experiment is conducted to validate the mathematical model. The mathematical model is used to evaluate the effect of geometric parameters on the head loss coefficient, the relative saturation coefficient and the oxygen absorption efficiency. It is found that the contraction ratio is a signi- ficant influencing factor, other than the relative length and the relative distance. Given the same relative length and relative distance, the head loss coefficient, the relative saturation coefficient and the oxygen absorption efficiency increase with the decrease of the contraction ratio, respectively. Given the same relative length and contraction ratio, the head loss coefficient increases with the in- crease of the relative distance firstly, and then decreases gradually, in contrast, the relative saturation coefficient and the oxygen ab- sorption efficiency decrease with the increase of the relative distance firstly, and then increase gradually, the relative saturation coefficient and the oxygen absorption efficiency are inversely proportional to the head loss coefficient, respectively.

  4. Efficacy of multimodality approach to sudden hearing loss.

    Science.gov (United States)

    Naiboğllu, Bariş; Külekçi, Semra; Sürmeli, Mehmet; Verim, Ayşegül; Kalaycik Ertugay, Çiğdem; İhvan, Önder; Şeneldir, Lütfü; Zer Toros, Sema

    2015-01-01

    This study aims to investigate whether addition of intratympanic steroid (ITS) to systemic steroid and hyperbaric oxygen (HBO) is effective in the treatment of sudden hearing loss (SHL). Between January 2008 and October 2011, 58 patients diagnosed with SHL were enrolled in the study. Twenty patients (11 males, 9 females; mean age 45.3±21 years; range 24 to 66 years) who received systemic steroid and HBO composed group 1, while 38 patients (19 males, 19 females; mean age 41.6±16 years; range 25 to 61 years) who received ITS in addition to systemic steroid and HBO composed group 2. Post-treatment hearing improvement was statistically significant in both groups in terms of the mean pure tone according to the Siegel's criteria (p0.05). However, there was a strong statistically significant difference in terms of profound hearing loss over 90 dB (phearing loss in group 1 benefited treatment, while addition of ITS to the treatment yielded success in six of 12 patients with profound hearing loss (50%) in group 2 (p<0.05). Addition of ITS to systemic steroid and HBO treatment may yield better results in patients with SHL. However, ITS injection seems beneficial for patients with profound SHL.

  5. A Clinical Analysis of Sudden Sensorineural Hearing Loss Cases

    Science.gov (United States)

    Lee, Hyun Soo; Lee, You Jae; Kang, Bo Sung; Lee, Ji Sung

    2014-01-01

    Background and Objectives High-dose systemic steroid therapy is the mainstay treatment for sudden sensorineural hearing loss (SSNHL). Recovery rates from SSNHL range are about 47-63% and are influenced by various prognostic factors. To evaluate the prognostic value of specific clinical parameters, we reviewed 289 cases by clinical and statistical analysis. Subjects and Methods This study included 289 patients with SSNHL who visited the Department of Otolaryngology at Soonchunhyang University Hospital from January 2005 to December 2012. The cases were reviewed retrospectively based on clinical charts. Hearing improvement was evaluated in relation to pure-tone audiogram results, duration between SSNHL onset and time of initial treatment, seasonal incidence, dizziness, patient age, degree of hearing loss, patterns of initial pure-tone audiogram and presence of underlying disease. Results Hearing improvement was observed in 196 of 289 (67.8%) patients; such improvement began within 7 days in most patients, followed by rapid hearing recovery. Cases that failed to show improvement within 14 days were unlikely to achieve hearing recovery. The more severe the hearing loss during the early stage, the lower the hearing recovery rates. Patients aged less than 60 years appear to have better prognosis of hearing improvement compared to those who are over 60 years. Conclusions Important prognostic factors for recovery in patients with SSNHL include the time of initiating treatment after symptom onset, the degree of early-stage hearing loss, and the age of the affected patient. PMID:25279228

  6. Prognostic predictors of sudden sensorineural hearing loss in defibrinogenation therapy.

    Science.gov (United States)

    Oya, Ryohei; Horii, Arata; Akazawa, Hitoshi; Osaki, Yasuhiro; Inohara, Hidenori

    2016-01-01

    Defibrinogenation therapy rather than corticosteroids therapy should be chosen for patients specifically with profound hearing loss and with initial high fibrinogen. Corticosteroids therapy is the standard treatment for sudden sensorineural hearing loss (SSNHL) and prognostic factors by this therapy were reported. Defibrinogenation therapy is one of the treatment options for SSNHL. Aims of this study were to identify prognostic factors and correlative markers with hearing improvement in treating SSNHL by defibrinogenation therapy. During the early phase of the study, consecutive 61 patients were treated by defibrinogenation therapy with batroxobin (50 units), whereas corticosteroids (500 mg/day of hydrocortisone tapered by 9 days) were used for consecutive 64 patients during the late phase. Blood data that could predict a complete recovery were identified. Coagulation/fibrinolysis markers correlated with hearing improvement by defibrinogenation therapy were investigated. Although there were no overall differences in hearing improvement between the two therapies, recovery rate in profound hearing loss patients was better in defibrinogenation therapy. In patients who showed complete recovery, serum fibrinogen level before treatment was significantly higher in the defibrinogenation group than the corticosteroid group. Responses of several fibrinolysis markers to defibrinogenation therapy evaluated by post-/pre-values were negatively correlated with hearing improvement.

  7. Noninvasive intratympanic dexamethasone treatment for sudden sensorineural hearing loss.

    Science.gov (United States)

    Zhang, Qiuying; Song, Haitao; Peng, Hao; Yang, Xuemei; Zhou, Junmei; Huang, Weining

    2012-06-01

    Noninvasive intratympanic dexamethasone perfusion (IDP) through the eustachian tube is an effective and safe therapy in cases of sudden sensorineural hearing loss (SSNHL). To investigate the effectiveness and safety of noninvasive IDP through the eustachian tube in patients with SSNHL. In this prospective study, 74 consecutive patients with SSNHL treated between September 2007 and March 2011 were enrolled: 35 patients fitted the criteria for initial treatment in the study (group I), while 39 patients, who had failed systemic therapy, received salvage treatment (group S). IDP through the eustachian tube was applied four times at 2-day intervals. Pure-tone test and tympanometry were performed before starting treatment, and 24 h and 1 week afterwards. All patients tolerated the procedure well. No perforation or infection was noticed in any of the patients at their last visit. With regard to the 74 patients who received intratympanic treatment, 80.0% (28 of 35) of the patients in group I and 64.1% (25 of 39) patients in group S had improvement in their hearing ability. Patients with simultaneous symptoms reported that the symptoms were relieved as follows: tinnitus, 73.3% (44/60); vertigo, 76.2% (16/21); and stuffy ear, 81.1% (30/37).

  8. Emission of scission neutrons in the sudden approximation

    Energy Technology Data Exchange (ETDEWEB)

    Carjan, N. [Universite Bordeaux 1, CNRS/IN2P3, Centre d' Etudes Nucleaires de Bordeaux Gradignan, UMR 5797, Chemin du Solarium, BP 120, 33175 Gradignan (France); Talou, P. [CEA-Cadarache, DEN/DER/SPRC/LEPh, Bat. 230, 13108 St-Paul-lez-Durance (France)]|[Nuclear Physics Group, Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Serot, O. [Nuclear Physics Group, Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2007-01-15

    At a certain finite neck radius during the descent of a fissioning nucleus from the saddle to the scission point, the attractive nuclear forces can no more withstand the repulsive Coulomb forces producing the neck rupture and the sudden absorption of the neck stubs by the fragments. At that moment, the neutrons, although still characterized by their pre-scission wave functions, find themselves in the newly created potential of their interaction with the separated fragments. Their wave functions become wave packets with components in the continuum. The probability to populate such states gives evidently the emission probability of neutrons at scission. In this way, we have studied scission neutrons for the fissioning nucleus {sup 236}U, using two-dimensional realistic nuclear shapes. Both the emission probability and the distribution of the emission points relative to the fission fragments strongly depend on the quantum numbers of the pre-scission state from which the neutron is emitted. In particular it was found that states with {omega}{pi} = 1/2+ dominate the emission. Depending on the assumed pre- and post-scission configurations and on the emission-barrier height, 30 to 50% of the total scission neutrons are emitted from 1/2+ states. Their emission points are concentrated in the region between the newly separated fragments. The upper limit for the total number of neutrons per scission event is predicted to lie between 0.16 and 1.73 (depending on the computational assumptions). (authors)

  9. Adjusting to a sudden “aging” of the lens.

    Science.gov (United States)

    Tregillus, Katherine E M; Werner, John S; Webster, Michael A

    2016-03-01

    Color perception is known to remain largely stable across the lifespan despite the pronounced changes in sensitivity from factors such as the progressive brunescence of the lens. However, the mechanisms and timescales controlling these compensatory adjustments are still poorly understood. In a series of experiments, we tracked adaptation in observers after introducing a sudden change in lens density by having observers wear glasses with yellow filters that approximated the average spectral transmittance of a 70-year-old lens. Individuals were young adults and wore the glasses for 5 days for 8 h per day while engaged in their normal activities. Achromatic settings were measured on a CRT before and after each daily exposure with the lenses on and off, and were preceded by 5 min of dark adaptation to control for short-term chromatic adaptation. During each day, there was a large shift in the white settings consistent with a partial compensation for the added lens density. However, there was little to no evidence of an afterimage at the end of each daily session, and participants’ perceptual nulls were roughly aligned with the nulls for short-term chromatic adaptation, suggesting a rapid renormalization when the lenses were removed. The long-term drift was also extinguished by brief exposure to a white adapting field. The results point to distinct timescales and potentially distinct mechanisms compensating for changes in the chromatic sensitivity of the observer.

  10. Response and resilience of Spartina alterniflora to sudden dieback

    Science.gov (United States)

    Marsh, Amanda; Blum, Linda K.; Christian, Robert R.; Ramsey III, Elijah W.; Rangoonwala, Amina

    2016-01-01

    We measured an array of biophysical and spectral variables to evaluate the response and recovery of Spartina alterniflora to a sudden dieback event in spring and summer 2004 within a low marsh in coastal Virginia, USA. S. alterniflora is a foundation species, whose loss decreases ecosystem services and potentiates ecosystem state change. Long-term records of the potential environmental drivers of dieback such as precipitation and tidal inundation did not evidence any particular anomalies, although Hurricane Isabel in fall 2003 may have been related to dieback. Transects were established across the interface between the dieback area and apparently healthy areas of marsh. Plant condition was classified based on ground cover within transects as dieback, intermediate and healthy. Numerous characteristics of S. alterniflora culms within each condition class were assessed including biomass, morphology and spectral attributes associated with photosynthetic pigments. Plants demonstrated evidence of stress in 2004 and 2005 beyond areas of obvious dieback and resilience at a multi-year scale. Resilience of the plants was evident in recovery of ground cover and biomass largely within 3 y, although a small remnant of dieback persisted for 8 y. Culms surviving within the dieback and areas of intermediate impact had modified morphological traits and spectral response that reflected stress. These morphometric and spectral differences among plant cover condition classes serve as guidelines for monitoring of dieback initiation, effects and subsequent recovery. Although a number of environmental and biotic parameters were assessed relative to causation, the reason for this particular dieback remains largely unknown, however.

  11. Sudden death due to forced ingestion of vinegar.

    Science.gov (United States)

    Shields, Lisa B E; Rolf, Cristin M; Hunsaker, John C

    2016-09-01

    Vinegar is a clear colorless liquid that commercially consists of 5% acetic acid. It has numerous benefits in everyday use, including culinary, medical, and cleaning. The ingestion of concentrated acetic acid is strongly discouraged and may have detrimental consequences, such as acute pancreatitis, disseminated intravascular coagulopathy, gastric and hepatic complications, upper airway obstruction, or death. We report the first case in the literature of a 5-year-old boy who experienced a sudden death due to ingestion of distilled white vinegar. The manner was homicide. There was evidence of nonfatal blunt force impacts of the head, trunk, and extremities. A pungent aromatic odor of the viscera, gastric/small bowel contents, and cranial cavity was noted at autopsy. A dusky gray discoloration of the gastric mucosa, small bowel, and pancreas was observed. Forensic pathologists should consider ingestion of vinegar when confronted with a compelling history as well as an aromatic odor suggesting vinegar and dusky gray discoloration of the gastric mucosa and small bowel. While vinegar is a common household item and has several advantages, it may prove fatal if ingested in large quantities.

  12. Transient Characteristics of Residual Meridional Circulation during Stratospheric Sudden Warming

    Institute of Scientific and Technical Information of China (English)

    DENG Shumei; CHEN Yuejuan; HUANG Yong; LUO Tao; BI Yun

    2011-01-01

    The residual meridional circulation derived from the transformed Eulerian-mean thermodynamic equation and continuity equation can be separated into two parts, the slowly varying diabatic circulation and the transient circulation, as demonstrated by others. We calculated and composite-analyzed the transient and diabatic circulation for 14 stratospheric sudden warming (SSW) events from 1979-2002 by using the daily ECMWF reanalysis data. Specifically, the transient residual meridional circulation was calculated both with and without inclusion of the eddy heat transport term in the transformed Eulerian-mean thermodynamic equation to investigate the importance of the eddy heat transport term. The results showed that calculations of transient residual meridional circulation present rapid variations during SSWs, with or without inclusion of the eddy heat transport term. Although the patterns of transient residual meridional circulation with the eddy heat transport term were similar to that without the eddy heat transport term during SSW, the magnitudes in the upper stratosphere and high-latitude regions differed. As for the diabatic circulation, its daily variations were small during SSW events, and its patterns were in agreement with its monthly average.

  13. Transient Characteristics of Residual Meridional Circulation during Stratospheric Sudden Warming

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The residual meridional circulation derived from the transformed Eulerian-mean thermodynamic equation and continuity equation can be separated into two parts,the slowly varying diabatic circulation and the transient circulation,as demonstrated by others.We calculated and composite-analyzed the transient and diabatic circulation for 14 stratospheric sudden warming(SSW) events from 1979-2002 by using the daily ECMWF reanalysis data.Specifically,the transient residual meridional circulation was calculated both with and without inclusion of the eddy heat transport term in the transformed Eulerian-mean thermodynamic equation to investigate the importance of the eddy heat transport term.The results showed that calculations of transient residual meridional circulation present rapid variations during SSWs,with or without inclusion of the eddy heat transport term.Although the patterns of transient residual meridional circulation with the eddy heat transport term were similar to that without the eddy heat transport term during SSW,the magnitudes in the upper stratosphere and high-latitude regions differed.As for the diabatic circulation,its daily variations were small during SSW events,and its patterns were in agreement with its monthly average.

  14. Glucocorticoid influence on prognosis of idiopathic sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Eduardo Amaro Bogaz

    2014-06-01

    Full Text Available INTRODUCTION: Idiopathic Sudden Sensorineural Hearing Loss (ISSHL is defined when a loss of at least 30 dB occurs in over 3 continuous frequencies, in up to 72 hours, of which etiology is not established, despite adequate investigation. Different types of treatment regimens have been proposed, but only glucocorticoids have shown some evidence of benefit in the literature. OBJECTIVE: To analyze whether the type of treatment or time of treatment with glucocorticoids have any influence on hearing recovery in ISSHL. METHODS: Observational retrospective cohort study. One hundred twenty-seven patients with ISSHL, treated at outpatient clinics between the years 2000 and 2010, were studied. We evaluated the prognostic correlation of the type of treatment and time to treatment with glucocorticoids and ISSHL. RESULTS: The absolute hearing gain and the relative hearing gain was as follows: 23.6 dB and 37.2%. Complete recovery was observed in 15.7% of patients, significant recovery in 27.6% and recovery in 57.5%. CONCLUSION: In this study, there was no difference between the use and nonuse of glucocorticoids in hearing improvement. However, when started within seven days after onset, the use of glucocorticoids was a factor of better prognosis.

  15. Vestibular evoked myogenic potential in sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Feroze Kancharu Khan

    2013-01-01

    Full Text Available Aim and Objective: To investigate saccular damage in patients with sudden sensorineural hearing loss (SSNHL with or without vertigo and to evaluate the saccular damage according to the hearing loss and presence or absence of vertigo. Materials and Methods: All tests done in this study were performed in the audio vestibular unit of ENT department from September 2009 to November 2010. Statistical Analysis Used: The association between the severity of hearing loss and changes in the vestibular evoked myogenic potential (VEMP recordings were assessed using descriptive statistics. The pattern of VEMP in different diseases and also the behavior of VEMP in presence or absence of vertigo were evaluated using SPSS 15. Results: Among 27 patients there were 11 cases of idiopathic SSNHL. Out of nine unaffected ears, 88% had normal and 12% had absent VEMP. Whereas out of 13 affected ears, only 53.9% had normal VEMP. Among all the 54 ears, 17 ears had normal hearing. In this group 76.47% had normal VEMP. The group with hearing loss > 90 dB had 61.53% absent VEMP. Conclusions: In patients with unilateral SSNHL, there was a tendency for the affected ear to have absent VEMP indicating the saccular involvement. The extent of saccular damage did not correspond to the amount of hearing loss or presence or absence of vertigo.

  16. A Multistation Study of Three Sudden Impulses During 1998

    Science.gov (United States)

    Rasmussen, K. R.; Engebretson, M. J.; Erickson, K. N.; Posch, J. L.; Hughes, W. J.; Arnoldy, R. L.; Rosenberg, T. J.

    2002-05-01

    Sudden impulses, stimulated by step-like changes in solar wind pressure, provide opportunities to study the propagation of ULF waves through Earth's magnetosphere-ionosphere system. We report here on high latitude ground-based observations of three SI events, on April 23, May 15, and May 29, 1998, that occurred near local noon in the American sector. Observations from fluxgate magnetometers in the cusp-latitude MACCS array in Arctic Canada and roughly conjugate U.S. and British sites in Antarctica are used to map out the horizontal propagation of the preliminary impulse of each SI across the high latitude ionosphere. In addition, search coil magnetometer data are used to determine the time of the first appearance of Pc 1-2 pulsations, which are presumably stimulated by the compression of plasma in the outer dayside magnetosphere, and signals from the auroral 427.8 nm photometer at South Pole Station are used to determine the time of arrival of the first precipitated energetic electrons associated with the SI. Comparisons of these arrival times will be used to infer the mode(s) of propagation of information about the SI from the outer magnetosphere to the cusp-latitude ionosphere.

  17. Sudden cardiac death in China: current status and future perspectives.

    Science.gov (United States)

    Zhang, Shu

    2015-10-01

    Sudden cardiac death (SCD) is a major cause of mortality worldwide. Similar to the number of SCDs in western countries including the USA, the number of SCDs in China is ∼544,000 annually. However, there are significant differences in patient characteristics between Chinese primary prevention population and U.S. primary prevention population. In contrast to western countries where implantable cardioverter-defibrillator (ICD) devices have been well adopted as a major effective method for both primary and secondary prevention of SCD, China has a low prevalence of ICD utilization (∼1.5 device per 1 million people). Socioeconomic and political factors, awareness and knowledge of SCD, and the difference in disease patterns have led to the underutilization of ICD in China. China, as the most populated and the second largest economic country in the world, has now taken variable approaches to address this pressing health problem and enhances the delivery of lifesaving therapies, including arrhythmia ablation and medical treatment besides ICD, to patients who are at risk of SCD.

  18. Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Sekiya, Kenichi; Fukushima, Munehisa; Teismann, Henning; Lagemann, Lothar; Kakigi, Ryusuke; Pantev, Christo; Okamoto, Hidehiko

    2016-01-25

    Sudden sensorineural hearing loss (SSHL) is characterized by acute, idiopathic hearing loss. The estimated incidence rate is 5-30 cases per 100,000 people per year. The causes of SSHL and the mechanisms underlying SSHL currently remain unknown. Based on several hypotheses such as a circulatory disturbance to the cochlea, viral infection, and autoimmune disease, pharmaco-therapeutic approaches have been applied to treat SSHL patients; however, the efficacy of the standard treatment, corticosteroid therapy, is still under debate. Exposure to intense sounds has been shown to cause permanent damage to the auditory system; however, exposure to a moderate level enriched acoustic environment after noise trauma may reduce hearing impairments. Several neuroimaging studies recently suggested that the onset of SSHL induced maladaptive cortical reorganization in the human auditory cortex, and that the degree of cortical reorganization in the acute SSHL phase negatively correlated with the recovery rate from hearing loss. This article reports the development of a novel neuro-rehabilitation approach for SSHL, "constraint-induced sound therapy (CIST)". The aim of the CIST protocol is to prevent or reduce maladaptive cortical reorganization by using an enriched acoustic environment. The canal of the intact ear of SSHL patients is plugged in order to motivate them to actively use the affected ear and thereby prevent progress of maladaptive cortical reorganization. The affected ear is also exposed to music via a headphone for 6 hr per day during hospitalization. The CIST protocol appears to be a safe, easy, inexpensive, and effective treatment for SSHL.

  19. Classifying the tropospheric precursor patterns of sudden stratospheric warmings

    Science.gov (United States)

    Bao, Ming; Tan, Xin; Hartmann, Dennis L.; Ceppi, Paulo

    2017-08-01

    Classifying the tropospheric precursor patterns of sudden stratospheric warmings (SSWs) may provide insight into the different physical mechanisms of SSWs. Based on 37 major SSWs during the 1958-2014 winters in the ERA reanalysis data sets, the self-organizing maps method is used to classify the tropospheric precursor patterns of SSWs. The cluster analysis indicates that one of the precursor patterns appears as a mixed pattern consisting of the negative-signed Western Hemisphere circulation pattern and the positive phase of the Pacific-North America pattern. The mixed pattern exhibits higher statistical significance as a precursor pattern of SSWs than other previously identified precursors such as the subpolar North Pacific low, Atlantic blocking, and the western Pacific pattern. Other clusters confirm northern European blocking and Gulf of Alaska blocking as precursors of SSWs. Linear interference with the climatological planetary waves provides a simple interpretation for the precursors. The relationship between the classified precursor patterns of SSWs and ENSO phases as well as the types of SSWs is discussed.

  20. [Right ventricular dysplasia and sudden death in young people].

    Science.gov (United States)

    Maresi, E; Albano, N; Procaccianti, P; Campesi, G

    1990-06-01

    In this study two autoptic cases of right ventricular dysplasia, observed in young and asymptomatic subjects who died suddenly are reported. In these patients, the "primary" myocardial atrophy involved the right ventricle, the right atrium and the conduction system: the sinoatrial node and the internodal pathways (in both cases) and the hisian bifurcation (only in the second case). The primary ventricular dysplasia was always associated with "secondary" transmural hyperplasia of the sub-epicardial fat tissue except for the anterior wall of the pulmonary infundibulum. According to the findings observed, we think that: 1) in all cases of right ventricular dysplasia a careful examination of the conduction system must be performed due to the fact that the lethal arrhythmias can be not only "hyperkinetic" but also "hypokinetic" arrhythmias; 2) right ventricular dysplasia is a dysplastic-congenital disease and transmural fatty hyperplasia depends both on "primary" myocardial atrophy and on the presence of sub-epicardial fat tissue; the latter is related to the age of the patient.