WorldWideScience

Sample records for modeling sudden depressurization

  1. Experimental study and modelization of a propane storage tank depressurization

    International Nuclear Information System (INIS)

    Veneau, Tania

    1995-01-01

    The risks associated with the fast depressurization of propane storage tanks reveals the importance of the 'source term' determination. This term is directly linked, among others, to the characteristics of the jet developed downstream of the breach. The first aim of this work was to provide an original data bank concerning drop velocity and diameter distributions in a propane jet. For this purpose, a phase Doppler anemometer bas been implemented on an experimental set-up. Propane blowdowns have been performed with different breach sizes and several initial pressures in the storage tank. Drop diameter and velocity distributions have been investigated at different locations in the jet zone. These measurements exhibited the fragmentation and vaporisation trends in the jet. The second aim of this work concerned the 'source term'. lt required to study the coupling between the fluid behaviour inside the tank and the flow through the breach. This model took into account the phase exchange when flashing occurred in the tank. The flow at the breach was described with an homogeneous relaxation model. This coupled modelization has been successfully and exhaustively validated. lt originality lies on the application to propane flows. (author) [fr

  2. HTGR depressurization analysis

    International Nuclear Information System (INIS)

    Boccio, J.L.; Colman, J.; Skalyo, J.; Beerman, J.

    1978-01-01

    Relaxation of the assumption of complete mixing of primary and secondary containment gases during HTGR depressurization has led to a study program designed to identify and selectively quantify the relevant gas dynamic processes which prevail during the depressurization event. Uncertainty in the degree of gas mixedness naturally leads to uncertainty in containment vessel design pressure and heat loads and possible combustion hazards therein. An analytical approach and modeling methodology of the exhaust jet structure/containment vessel interaction during penetration failures are presented

  3. Numerical modeling of the waves evolution generated by the depressurization of the vessels containing a supercritical parameters coolant

    Science.gov (United States)

    Alekseev, Maksim V.; Vozhakov, Ivan S.; Lezhnin, Sergey I.; Pribaturin, Nikolay A.

    2017-10-01

    The development of power plants focuses on increasing the parameters of water coolants up to a supercritical level. Depressurization of the unit circuits with such a coolant leads to emergency situations. Their scenarios can change significantly with the variation of initial pressure and temperature before the start of depressurization. When the pressure drops from the supercritical single-phase region of the initial thermodynamic parameters of the coolant, either the liquid boils up, or the vapor is condensed. Because of the rapid pressure decrease, the phase transition can be non-equilibrium that must be taken into account in the simulation. In the present study, an axisymmetric problem of the outflow of a water coolant from the pipe butt-end is considered. The equations of continuity, momentum and energy for a two-phase homogeneous mixture are solved numerically. The vapor and liquid properties are calculated using the TTSE software package (The Tabular Taylor Series Expansion Method). On the basis of the computer complex LCPFCT (The Flux-Corrected Transport Algorithm) the program code was developed for solving numerous problems on the depressurization of vessels or pipelines, containing superheated water or gas under high pressure. Different variants of outflow in the external model atmosphere and generation of waves are analyzed. The calculated data on the interaction of pressure waves with a barrier are calculated. To describe phase transitions, an asymptotic relaxation model of nonequilibrium evaporation and condensation has been created and tested.

  4. Consequence analysis of depressurization accidents

    International Nuclear Information System (INIS)

    Foley, J.E.

    1976-01-01

    The consequences of the depressurization accidents for the High-Temperature Gas-Cooled Reactor are investigated. A consequence model is developed that is used to delineate the parameters that are important to the consequence calculations. A numerical example of the calculational technique is given

  5. 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.

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

    International Nuclear Information System (INIS)

    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 0 C at 38 hours following the transient initiation, and the pebble-bed peak temperature was 1647.8 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. Effect of Suddenly Turning on Interactions in the Luttinger Model

    Science.gov (United States)

    Cazalilla, M. A.

    2006-10-01

    The evolution of correlations in the exactly solvable Luttinger model (a model of interacting fermions in one dimension) after a suddenly switched-on interaction is analytically studied. When the model is defined on a finite-size ring, zero-temperature correlations are periodic in time. However, in the thermodynamic limit, the system relaxes algebraically towards a stationary state which is well described, at least for some simple correlation functions, by the generalized Gibbs ensemble recently introduced by Rigol et al. (cond-mat/0604476). The critical exponent that characterizes the decay of the one-particle correlation function is different from the known equilibrium exponents. Experiments for which these results can be relevant are also discussed.

  8. Depressurization device for reactor container

    International Nuclear Information System (INIS)

    Okamuro, Tatsuo; Okura, Minoru; Tsuji, Akio; Tate, Hitoshi; Karasawa, Hidetoshi; Kawabe, Ken-ichi.

    1992-01-01

    In a depressurization device of a reactor container, a means for maintaining the level of pool water to a predetermined range is disposed to a wet cleanup device, and a water recycling channel is also disposed for recycling the pool water. Preferably, a cooling means is disposed to a portion of the water recycling channel. Further, a means for cleaning a radioactive material adsorbing filter device is disposed. Then, reduction of water amount is prevented by maintaining the level of the pool water and the concentration of captured water soluble radioactive material is not increased to prevent re-evaporation of radioactive materials. Further, flow in the pool water is stabilized by a water recycling channel to, eliminate interference between an uprising stream and a downstream. Since re-evaporation of radioactive materials is prevented during operation of the depressurization device and the amount of pool water is not decreased, effective radioactive material removing function is always provided. Further, abnormal elevation of the pool water level or disturbance on the liquid surface are suppressed, to decrease the amount of scattering liquid droplets. The wet type cleanup device can be made compact and the volume of radioactive materials released to surrounding circumstance can be reduced remarkably. (N.H.)

  9. Tissue and Animal Models of Sudden Cardiac Death

    Science.gov (United States)

    Sallam, Karim; Li, Yingxin; Sager, Philip T.; Houser, Steven R.; Wu, Joseph C.

    2015-01-01

    Sudden Cardiac Death (SCD) is a common cause of death in patients with structural heart disease, genetic mutations or acquired disorders affecting cardiac ion channels. A wide range of platforms exist to model and study disorders associated with SCD. Human clinical studies are cumbersome and are thwarted by the extent of investigation that can be performed on human subjects. Animal models are limited by their degree of homology to human cardiac electrophysiology including ion channel expression. Most commonly used cellular models are cellular transfection models, which are able to mimic the expression of a single ion channel offering incomplete insight into changes of the action potential profile. Induced pluripotent stem cell derived Cardiomyocytes (iPSC-CMs) resemble, but are not identical, to adult human cardiomyocytes, and provide a new platform for studying arrhythmic disorders leading to SCD. A variety of platforms exist to phenotype cellular models including conventional and automated patch clamp, multi-electrode array, and computational modeling. iPSC-CMs have been used to study Long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, hypertrophic cardiomyopathy and other hereditary cardiac disorders. Although iPSC-CMs are distinct from adult cardiomyocytes, they provide a robust platform to advance the science and clinical care of SCD. PMID:26044252

  10. Sudden Deafness

    Science.gov (United States)

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

  11. 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.

  12. Simulations of severe slugging during depressurization of an oil/gas pipeline

    Directory of Open Access Journals (Sweden)

    M. Nordsveen

    1997-01-01

    Full Text Available Dynamic simulators for pipelines with multiphase flow have proved to be important computational tools for both design and operational support of oil and gas production systems. One important aim of such simulators is to predict the arrival time and magnitude of outlet liquid transients after production changes made by an operator of a pipeline. A multiphase flow simulator (OLGA-94.1 with a two-fluid model has been applied to simulate depressurization of a pipeline during a shutdown procedure. During depressurization liquid slugs may form and propagate towards the outlet. The importance of the numerical method for predictions of such transients is demonstrated by using an Eulerian, finite difference, implicit, upwind scheme both with and without a front tracking scheme. First the initial conditions for the depressurization is established from a shut-down simulation where the production at the inlet is closed down, and the liquid comes to rest at low points along the pipeline. A realistic depressurization is simulated by opening a choke at the outlet of the pressurized pipeline. The numerical scheme without front tracking (standard scheme gives outlet gas and liquid flow rates which are smeared out in time due to numerical diffusion. Simulations with the front tracking scheme give intermittent gas-liquid flow arriving as sharp fronts at the outlet. The total remaining fluid in the pipeline after the depressurization is larger when using the standard scheme.

  13. The sudden coalescene model of the boiling crisis

    Energy Technology Data Exchange (ETDEWEB)

    Carrica, P.M.; Clausse, A. [Centro Atomico Bariloche and Instituto Balseiro, Bariloche (Argentina)

    1995-09-01

    A local two-phase flow integral model of nucleate boiling and crisis is presented. The model is based on average balances on a control volume, yielding to a set of three nonlinear differential equations for the local void fraction, bubble number density and velocity. Boiling crisis as critical heat flux is interpreted as a dynamic transition caused by the coalescence of bubbles near the heater. The theoretical dynamic model is compared with experimental results obtained for linear power ramps in a horizontal plate heater in R-113, showing an excellent qualitative agreement.

  14. Experiment and analyses on intentional secondary-side depressurization during PWR small break LOCA. Effects of depressurization rate and break area on core liquid level behavior

    International Nuclear Information System (INIS)

    Asaka, Hideaki; Ohtsu, Iwao; Anoda, Yoshinari; Kukita, Yutaka

    1997-01-01

    The effects of the secondary-side depressurization rate and break area on the core liquid level behavior during a PWR small-break LOCA were studied using experimental data from the Large Scale Test Facility (LSTF) and by using analysis results obtained with a JAERI modified version of RELAP5/MOD3 code. The LSTF is a 1/ 48 volumetrically scaled full-height integral model of a Westinghouse-type PWR. The code reproduced the thermal-hydraulic responses, observed in the experiment, for important parameters such as the primary and secondary side pressures and core liquid level behavior. The sensitivity of the core minimum liquid level to the depressurization rate and break area was studied by using the code assessed above. It was found that the core liquid level took a local minimum value for a given break area as a function of secondary side depressurization rate. Further efforts are, however, needed to quantitatively define the maximum core temperature as a function of break area and depressurization rate. (author)

  15. A model of spreading of sudden events on social networks

    Science.gov (United States)

    Wu, Jiao; Zheng, Muhua; Zhang, Zi-Ke; Wang, Wei; Gu, Changgui; Liu, Zonghua

    2018-03-01

    Information spreading has been studied for decades, but its underlying mechanism is still under debate, especially for those ones spreading extremely fast through the Internet. By focusing on the information spreading data of six typical events on Sina Weibo, we surprisingly find that the spreading of modern information shows some new features, i.e., either extremely fast or slow, depending on the individual events. To understand its mechanism, we present a susceptible-accepted-recovered model with both information sensitivity and social reinforcement. Numerical simulations show that the model can reproduce the main spreading patterns of the six typical events. By this model, we further reveal that the spreading can be speeded up by increasing either the strength of information sensitivity or social reinforcement. Depending on the transmission probability and information sensitivity, the final accepted size can change from continuous to discontinuous transition when the strength of the social reinforcement is large. Moreover, an edge-based compartmental theory is presented to explain the numerical results. These findings may be of significance on the control of information spreading in modern society.

  16. BLOW.MOD2: program for a vessel depressurization calculation with the contribution of structures

    International Nuclear Information System (INIS)

    Doval, A.

    1990-01-01

    The BLOW.MOD2 program developed to calculate pressure vessels' depressurization is presented, considering heat contribution of the structures. The results are opposite to those obtained from other more complex numerical models, being the comparison extremely satisfactory. BLOW.MOD2 is a software of the 'Systems Sub-Branch', INVAP S.E. (Author) [es

  17. Characteristics and design improvement of AP1000 automatic depressurization system

    International Nuclear Information System (INIS)

    Jin Fei

    2012-01-01

    Automatic depressurization system, as a specialty of AP1000 Design, enhances capability of mitigating design basis accidents for plant. Advancement of the system is discussed by comparing with traditional PWR design and analyzing system functions, such as depressurizing and venting. System design improvement during China Project performance is also described. At the end, suggestions for the system in China Project are listed. (author)

  18. Model intercomparison of sea-level response to sudden Antarctic ice-shelf collapse

    Science.gov (United States)

    Pattyn, Frank; Sun, Sainan; Golledge, Nicholas

    2017-04-01

    The magnitude of the Antarctic ice sheet's contribution to global sea level is dominated by the potential of its marine sectors to become unstable and collapse to ocean (and atmospheric) forcing. Ice shelf buttressing is a key element in the stability of the Antarctic ice sheet. Therefore, a useful model experiment to test this stability is the sudden removal of all floating ice shelves. It serves several purposes: (i) investigating an upper bound of Antarctic mass loss, and (ii) testing numerical ice sheet models on their sensitivity to grounding line migration and marine ice sheet instability (MISI). Two types of de-buttressing are investigated, i.e., (i) sudden removal followed by ice-shelf regrowth due to increased ice discharge across the grounding line, and (ii) without ice shelf regrowth after de-buttressing (so-called float-kill). Experiments are carried out with two state-of-the-art marine ice sheet models (f.ETISh and PISM) and different settings of grounding-line treatment. For the f.ETISh model these settings pertain to grounding-line flux conditions according to power-law basal sliding and Coulomb friction; for PISM this includes different settings on transition zone width and grounding-line interpolation. Results of the experiments show that regrowth of ice shelves after sudden de-buttressing stabilizes grounding lines and reduces the effect of MISI. Float-kill conditions lead to significant mass loss, which is further exacerbated by the type of grounding-line treatment, i.e., Coulomb friction renders grounding lines more sensitive (Tsai et al., 2015). However, compared to recent model studies where effects of hydro-fracturing and cliff-failure are considered (DeConto and Pollard, 2016), similar amounts of ice loss are only obtained when the highest grounding-line sensitivity is considered.

  19. Using process control concepts to model conditions required for sudden-onset occupational injuries.

    Science.gov (United States)

    Keyserling, W Monroe; Smith, Gordon S

    2007-07-01

    Sudden-onset injury results from a momentary energy exchange between an agent and host, producing immediately discernible tissue damage. These injuries are common in both occupational and nonoccupational settings; typical causes include falls, mechanical contact/crushing, exposure to temperature extremes, and exposure to electrical current. We review epidemiologic and engineering approaches to injury prevention and propose a process control model for describing risk-of-exposure to injury agents during the Pre-event phase of sudden-onset injury. Process control is a proactive approach to quality engineering that is based on the premise of preventing defective products from being manufactured in the first place, instead of relying on reactive inspections to detect defects at the end of the manufacturing process. Principles of process control can be applied by occupational health and safety professionals to prevent workplace injury. The proposed model describes how work activities (process inputs) cause risk-of-exposure to injury agents to fluctuate over the course of a work shift. Risk-of-exposure is a complex function with many input factors including: the nature/magnitude of hazards, the presence and effectiveness of engineering controls, safety climate, management attitudes and practices, the surrounding work environment, the physical and mental states of the worker, and the quality and quantity of supervision and training. Injury can occur only when this function crosses a certain threshold and the host is exposed to injurious energy via physical contact. Certain factors that contribute to risk-of-exposure are stable for extended time periods (weeks, months, years), whereas other factors are transient (durations of minutes or seconds). The model extends classical work by Haddon and others, provides preliminary insights to designing epidemiologic studies and developing fault-tolerant work systems, and illustrates how interdisciplinary approaches can improve our

  20. 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

  1. Simulation of Fission Product Liftoff Behavior During Depressurization Transients

    International Nuclear Information System (INIS)

    Tak, Nam-il; Yoon, Churl; Lee, Sung Nam

    2016-01-01

    As one of crucial technologies for the NHDD project, the development of the GAMMA-FP code is on-going. The GAMMA-FP code is targeted for fission product transport analysis under accident conditions. A well-known experiment named COMEDIE considered two important phenomena, i.e., fission product plateout and liftoff, for fission product transport within the primary circuit of a prismatic high temperature gas cooled reactor. The accumulated fission products on the structural material via the plateout can be liftoff during a blowdown phase after a pipe break accident. Since the fission product liftoff can increase a radioactivity risk, it is important to predict the amount of fission product liftoff during depressurization accidents. In this work, a model for fission product liftoff is implemented into the GAMMA-FP code and the GAMMA-FP code with the implemented model is validated using the COMEDIE blowdown test data. The results of GAMMA-FP show that the GAMMA-FP code can reliably simulate a pressure transient during blowdown phase after a pipe break accident. In addition, a reasonable amount of fission product liftoff was predicted by the GAMMA-FP code. The maximum difference between the measured and predicted liftoff fraction was less than a factor of 10. More in-depth study is required to increase the accuracy of prediction for a fission product liftoff

  2. Radon mitigation by depressurization of concrete walls and slabs.

    Science.gov (United States)

    Leung, J K; Tso, M Y; Hung, L C

    1999-10-01

    A special laboratory, the Radioisotope Unit Radon Analysis Laboratory, has been built for the study of radon mitigation in high-rise buildings. Reduction of radon exhalation rate from concrete walls as a result of depressurizing the interior of the wall was studied by embedding tunnels in a wall and pumping away the radon in the wall. The reduction in exhalation rate was quantified against the applied depressurization, the separation of the tunnels, the depth of the tunnel, and the thickness of the wall. Results show that radon exhalation rate from a wall embedded with tunnels can be reduced significantly by applying depressurization. For example, the radon exhalation rate from a wall of 20 cm thickness containing tunnels separated by 0.7 m can be reduced by 60% at a depressurization of 67 kPa (20 in Hg). This paper summarizes the effect of depressurization and suggests practical ways of applying the technique in radon mitigation in high-rise commercial buildings.

  3. Basement depressurization using dwelling mechanical exhaust ventilation system

    International Nuclear Information System (INIS)

    Collignan, B.; O'Kelly, P.; Pilch, E.

    2004-01-01

    The mechanical ventilation exhaust system is commonly used in France to generate air renewal into building and especially into dwelling. It consists of a permanent mechanical air extraction from technical rooms (kitchen, bathrooms and toilets) using a unique fan connected to exhaust ducts. Natural air inlets in living room and bed rooms ensure an air flow from living spaces towards technical rooms. To fight against radon into building, the most recognised efficient technique is the Soil Depressurization System (S.D.S.) consisting in depressurizing the house basement. The aim of this study is to test the ability of the dwelling mechanical ventilation system to depressurize the basement in conjunction with air renewal of a house. For that purpose, a S.D.S. has been installed in an experimental house at CSTB during its construction. At first, tests undertaken with a variable velocity fan connected to the S.D.S. have characterised the permeability of the basement. It is shown that basement can be depressurized adequately with a relatively low air flow rate. At a second stage, S.D.S. has been connected to the exhaust ventilation fan used for the mechanical ventilation of the house. Results obtained show the ability of such ventilation system to generate sufficient depressurization in the basement and to ensure simultaneously adequate air change rate in the dwelling. (author)

  4. 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.

  5. Study on depressurization measurements and effect in PWR

    International Nuclear Information System (INIS)

    Ji Duan; Cao Xuewu

    2006-01-01

    Implementation of new regulations on nuclear powered plant design and operation raise new design and management requirement for plants, and the operational plants also need accident management to enhance the reactor operation safety. Thus, for sake of reducing risk of high-pressure and mitigating the consequence, depressurization is a measure carried out to reduce primary pressure. With SCDAP/RELAP5 this paper studies the depressurization measurements and effect factors in pressurized water reactor under the important severe accident sequences induced by very small break lost of coolant accident (VSBLOCA), anticipated transient without scram (ATWS) and station blackout (SBO) plus auxiliary feedwater failure. (author)

  6. 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.

  7. Examining Variability in Model Skill During the 7 January 2013 Sudden Stratospheric Warming Event

    Science.gov (United States)

    Blufer, Jonathan L.

    Recent analyses of numerical weather prediction models have shown that stratospheric regime changes (e.g. strong and weak vortex events) are not skillfully predicted at medium-range lead times. Motivated by these recent analyses, this thesis investigates the sources of variability in stratospheric forecast skill amongst several operational models initiated at different lead times prior to the 7 January 2013 sudden stratospheric warming (SSW). This study extends upon a previous analysis by the Stratospheric Network for the Assessment of Predictability (SNAP), which concluded that a change in forecast lead-time from 15 to 10 days increased model skill in predicting the 2013 SSW by roughly 50 percent. The sources of such variability in predictive skill are investigated further in this thesis. Coordinated reforecasts from the SNAP dataset are used to examine model variability and forecast skill in six medium-range operational ensemble forecast models. Both elliptical diagnostics of the polar vortex that quantify the vortex eccentricity, center longitude and latitude, and area, as well as zonal mean metrics are used to assess model errors and biases in the stratosphere. Ensemble skill is categorized into low and high error composite groups according to two separate metrics: the strength of the 10-hPa zonal mean zonal wind at 60?N and the center latitude of the 10-hPa vortex ellipse. Analysis reveals that ensemble members forecasting an ellipse center located equatorward of 70°N prior to 7 January 2013 had greater skill in predicting an easterly 10-hPa zonal mean zonal wind regime at the time of verified SSW onset. It is hypothesized that model error in forecasting thermodynamic processes linked to the SSW precursor tropospheric blocking in the N. Atlantic resulted in systematic biases and variability in dynamical forcing (e.g. upward wave activity flux) into the polar stratosphere in forecasts of the 7 January 2013 SSW event. Results indicate that errors in maintaining

  8. 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.

  9. Maximum Recoverable Gas from Hydrate Bearing Sediments by Depressurization

    KAUST Repository

    Terzariol, Marco

    2017-11-13

    The estimation of gas production rates from hydrate bearing sediments requires complex numerical simulations. This manuscript presents a set of simple and robust analytical solutions to estimate the maximum depressurization-driven recoverable gas. These limiting-equilibrium solutions are established when the dissociation front reaches steady state conditions and ceases to expand further. Analytical solutions show the relevance of (1) relative permeabilities between the hydrate free sediment, the hydrate bearing sediment, and the aquitard layers, and (2) the extent of depressurization in terms of the fluid pressures at the well, at the phase boundary, and in the far field. Close form solutions for the size of the produced zone allow for expeditious financial analyses; results highlight the need for innovative production strategies in order to make hydrate accumulations an economically-viable energy resource. Horizontal directional drilling and multi-wellpoint seafloor dewatering installations may lead to advantageous production strategies in shallow seafloor reservoirs.

  10. 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.

  11. Control device for start-up of reactor depressurization system

    International Nuclear Information System (INIS)

    Suzuki, Hiroshi; Saito, Minoru; Oda, Shingo; Miura, Satoshi; Hashimoto, Koji; Tate, Hitoshi; Fujii, Kazunobu

    1998-01-01

    The present invention concerns are emergency reactor core cooling system (ECCS) of a BWR type reactor and provides a control device for start-up of an automatic depressurization system. Namely, the device has an object of preventing erroneous opening of a main steam escape safety value when testing a start-up signal circuit of an automatic depressurization system for testing the automatic depressurization system. A start-up signal circuit receives both signals of a reactor container pressure high signal and a reactor pressure vessel water level low signal and outputs an automatic start-up signal for compulsorily opening a main steam escape safety valve automatically. A test switch having a self-holding circuit is disposed to a central control chamber. A test signal circuit is disposed for preventing transfer of an erroneous start-up signal to the main steam escape safety valve due to a simulation signal during output test signals by the test switch. (I.S.)

  12. Accurate representation of primary coolant system depressurization for high flux isotope reactor transients

    International Nuclear Information System (INIS)

    Wendel, M.W.

    1993-01-01

    Because the High Flux Isotope Reactor primary coolant system is typically all liquid, the pressure falls very rapidly if a leak forms in the primary piping. This depressurization is the predominate phenomenon in the consideration of the loss-of-coolant-accident analysis that has been completed recently for the High Flux Isotope Reactor Safety Analysis Report. Small differences in the rate of depressurization can significantly affect the safety margin. A RELAP5 thermal-hydraulic input model has been developed, but the capabilities of the RELAP5 code do not automatically take into account the effect on the system pressure of a stretching or shrinkage in the pressure boundary. Because this change in the pressure boundary is so important in an all-liquid system, a scheme has been developed to account for the effect implementation of the structural elasticity model involved using the control variable capability of RELAP5. During simulated transients involving rapid pressure changes, mass is added to or taken away from the primary system depending on whether the system is decreasing or increasing in pressure. By doing so, a more realistic system response to transients involving significant pressure changes is obtained. The model has been used to perform various HFIR transient simulations including loss-of-coolant accidents (LOCAs), loss of offsite power, and loss-of-secondary-cooling transients. Results for a small break LOCA are presented with and without the elasticity model in place

  13. Reactor calculations CP1: Design Basis Accident, depressurization, refilling. RELAP4-MOD6, SATAN6, TRAC PF1

    International Nuclear Information System (INIS)

    Macheteau, Y.; Menessier, D.; Pochard, R.; Trefouret, P.

    1985-01-01

    This paper presents results of calculations obtained from the codes TRAC-PF1, RELAP4-MOD6 and SATAN6. After a recall of the different modelling processes, the results are given; they concern: depressurization (pressure evolution, break flow rate); first peak of temperature (fuel can, departure nucleate boiling and stagnation point); by-pass and refilling. Finally, the advantages of TRAC-PF1 are pointed out [fr

  14. 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.

  15. Ketogenic diet treatment increases longevity in Kcna1-null mice, a model of sudden unexpected death in epilepsy.

    Science.gov (United States)

    Simeone, Kristina A; Matthews, Stephanie A; Rho, Jong M; Simeone, Timothy A

    2016-08-01

    Individuals with poorly controlled epilepsy have a higher risk for sudden unexpected death in epilepsy (SUDEP). With approximately one third of people with epilepsy not achieving adequate seizure control with current antiseizure drugs, there is a critical need to identify treatments that reduce risk factors for SUDEP. The Kcna1-null mutant mouse models risk factors and terminal events associated with SUDEP. In the current study, we demonstrate the progressive nature of epilepsy and sudden death in this model (mean age of mortality (± SEM), postnatal day [P] 42.8 ± 1.3) and tested the hypothesis that long-term treatment with the ketogenic diet (KD) will prolong the life of Kcna1-null mice. We found that the KD postpones disease progression by delaying the onset of severe seizures and increases the lifespan of these mutant mice by 47%. Future studies are needed to determine the mechanisms underlying the KD effects on longevity. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  16. Characterization of pore structure in cement-based materials using pressurization-depressurization cycling mercury intrusion porosimetry (PDC-MIP)

    International Nuclear Information System (INIS)

    Zhou Jian; Ye Guang; Breugel, Klaas van

    2010-01-01

    Numerous mercury intrusion porosimetry (MIP) studies have been carried out to investigate the pore structure in cement-based materials. However, the standard MIP often results in an underestimation of large pores and an overestimation of small pores because of its intrinsic limitation. In this paper, an innovative MIP method is developed in order to provide a more accurate estimation of pore size distribution. The new MIP measurements are conducted following a unique mercury intrusion procedure, in which the applied pressure is increased from the minimum to the maximum by repeating pressurization-depressurization cycles instead of a continuous pressurization followed by a continuous depressurization. Accordingly, this method is called pressurization-depressurization cycling MIP (PDC-MIP). By following the PDC-MIP testing sequence, the volumes of the throat pores and the corresponding ink-bottle pores can be determined at every pore size. These values are used to calculate pore size distribution by using the newly developed analysis method. This paper presents an application of PDC-MIP on the investigation of the pore size distribution in cement-based materials. The experimental results of PDC-MIP are compared with those measured by standard MIP. The PDC-MIP is further validated with the other experimental methods and numerical tool, including nitrogen sorption, backscanning electron (BSE) image analysis, Wood's metal intrusion porosimetry (WMIP) and the numerical simulation by the cement hydration model HYMOSTRUC3D.

  17. Depressurization study of CAREM 25 reactor considering the structures heat transfer

    International Nuclear Information System (INIS)

    Doval, A.

    1990-01-01

    This work presents the CAREM 25 reactor depressurization analysis results as an alternative form of accidents mitigation. Such results will help to determine design pressure valves for the emergency injection system as well as the depressurization valve diameter. Calculations were made with BLOW.MOD2 program. (Author) [es

  18. Depressurization as an accident management strategy to minimize the consequences of direct containment heating

    International Nuclear Information System (INIS)

    Hanson, D.J.; Golden, D.W.; Chambers, R.; Miller, J.D.; Hallbert, B.P.; Dobbe, C.A.

    1990-10-01

    Probabilistic Risk Assessments (PRAs) have identified severe accidents for nuclear power plants that have the potential to cause failure of the containment through direct containment heating (DCH). Prevention of DCH or mitigation of its effects may be possible using accident management strategies that intentionally depressurize the reactor coolant system (RCS). The effectiveness of intentional depressurization during a station blackout TMLB' sequence was evaluated considering the phenomenological behavior, hardware performance, and operational performance. Phenomenological behavior was calculated using the SCDAP/RELAP5 severe accident analysis code. Two strategies to mitigate DCH by depressurization of the RCS were considered. One strategy, called early depressurization, assumed that the reactor head vent and pressurizer power-operated relief valves (PORVs) were latched open at steam generator dryout. The second strategy, called late depression, assumed that the head vent and PORVs were latched open at a core exit temperature of ∼922 K (1200 degree F). Depressurization of the RCS to a low value that may mitigate DCH was predicted prior to reactor pressure vessel breach for both early and late depressurization. The strategy of late depressurization is preferred over early depressurization because there are greater opportunities to recover plant functions prior to core damage and because failure uncertainties are lessened. 22 refs., 38 figs., 6 tabs

  19. Depressurization as an accident management strategy to minimize the consequences of direct containment heating

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, D.J.; Golden, D.W.; Chambers, R.; Miller, J.D.; Hallbert, B.P.; Dobbe, C.A. (EG and G Idaho, Inc., Idaho Falls, ID (USA))

    1990-10-01

    Probabilistic Risk Assessments (PRAs) have identified severe accidents for nuclear power plants that have the potential to cause failure of the containment through direct containment heating (DCH). Prevention of DCH or mitigation of its effects may be possible using accident management strategies that intentionally depressurize the reactor coolant system (RCS). The effectiveness of intentional depressurization during a station blackout TMLB' sequence was evaluated considering the phenomenological behavior, hardware performance, and operational performance. Phenomenological behavior was calculated using the SCDAP/RELAP5 severe accident analysis code. Two strategies to mitigate DCH by depressurization of the RCS were considered. One strategy, called early depressurization, assumed that the reactor head vent and pressurizer power-operated relief valves (PORVs) were latched open at steam generator dryout. The second strategy, called late depression, assumed that the head vent and PORVs were latched open at a core exit temperature of {approximately}922 K (1200{degree}F). Depressurization of the RCS to a low value that may mitigate DCH was predicted prior to reactor pressure vessel breach for both early and late depressurization. The strategy of late depressurization is preferred over early depressurization because there are greater opportunities to recover plant functions prior to core damage and because failure uncertainties are lessened. 22 refs., 38 figs., 6 tabs.

  20. Spreading depolarization in the brainstem mediates sudden cardiorespiratory arrest in mouse SUDEP models.

    Science.gov (United States)

    Aiba, Isamu; Noebels, Jeffrey L

    2015-04-08

    Cardiorespiratory collapse after a seizure is the leading cause of sudden unexpected death in epilepsy (SUDEP) in young persons, but why only certain individuals are at risk is unknown. To identify a mechanism for this lethal cardiorespiratory failure, we examined whether genes linked to increased SUDEP risk lower the threshold for spreading depolarization (SD), a self-propagating depolarizing wave that silences neuronal networks. Mice carrying mutations in Kv1.1 potassium channels (-/-) and Scn1a sodium ion channels (+/R1407X) phenocopy many aspects of human SUDEP. In mutant, but not wild-type mice, seizures initiated by topical application of 4-aminopyridine to the cortex led to a slow, negative DC potential shift recorded in the dorsal medulla, a brainstem region that controls cardiorespiratory pacemaking. This irreversible event slowly depolarized cells and inactivated synaptic activity, producing cardiorespiratory arrest. Local initiation of SD in this region by potassium chloride microinjection also elicited electroencephalographic suppression, apnea, bradycardia, and asystole, similar to the events seen in monitored human SUDEP. In vitro study of brainstem slices confirmed that mutant mice had a lower threshold for SD elicited by metabolic substrate depletion and that immature mice were at greater risk than adults. Deletion of the gene encoding tau, which prolongs life in these mutants, also restored the normal SD threshold in Kv1.1-mutant mouse brainstem. Thus, brainstem SD may be a critical threshold event linking seizures and SUDEP. Copyright © 2015, American Association for the Advancement of Science.

  1. Observation and Modeling of the Generation Mechanism of Ion Upflow during Sudden Commencement

    Science.gov (United States)

    Zou, S.; Ozturk, D. S.; Li, C.; Varney, R. H.; Reimer, A.

    2017-12-01

    Sudden commencement (SC) induced by solar wind pressure enhancement can produce significant global impact on the coupled magnetosphere-ionosphere (MI) system, and its effects have been studied extensively using ground magnetometers and coherent scatter radars. However, very limited observations have been reported about the effects of SC on the ionospheric plasma. We study the ionosphere response to the SC using the Poker Flat incoherent scatter radar (PFISR) and numerical simulations. A detailed case study of SC during the 17 March 2015 storm was conducted. PFISR observed lifting of the F region ionosphere, transient field-aligned ion upflow, prompt but short-lived ion temperature increase, subsequent F region density decrease, and persistent electron temperature increase. A global magnetohydrodynamic (MHD) simulation has been carried out to characterize the SC-induced current, convection, and magnetic perturbations. Simulated magnetic perturbations at Poker Flat show a satisfactory agreement with observations. The simulation provides a global context for linking localized PFISR observations to large-scale dynamic processes in the MI system. Following the case study, we also perform a statistical study of the effects of SC on the ionosphere focusing on the magnetic local time and latitudinal asymmetries using PFISR and GPS TEC.

  2. 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.

  3. Analysis of trends in fuel rod depressurization and determination of 'gas leak' and 'pellet-water interaction' type failures using radiation monitoring techniques of fuel rod leak tightness

    International Nuclear Information System (INIS)

    Panov, E.A.; Shestakov, Yu.M.; Miglo, V.N.

    1993-01-01

    Analysis of fuel rod failures in the Light Water Reactor operation is presented. Analysis includes the mechanism of formation and development of fuel rod cladding failure until through-wall defects appear (welding defects; inner hydriding defects; pellet-cladding interaction; crud deposit - intensified corrosion) as well as factors that determine defects propagation after fuel rod depressurization (metal condition in the vicinity of defect determined by the mechanism of formation and propagation defect; operational transients; degree of core cooldown after depressurization during preventive maintenance). Possibilities of in-service monitoring of fuel rod through-wall crack propagation using normal tools of cladding back-tightness monitoring are addressed and used in the course of analysis. Characteristics and values are presented for radiation parameters for fuel assemblies during propagation of defects with different degrees of rod depressurization, including ''gas leak'', cladding crack and ''open pellet-water interaction'' with potential particulate fission product release from the damaged rods as well as after formation of recurring defects. Based on experimental data on specific activity of different iodine isotopes in the primary coolant, a mathematical model to analyse defect propagation trends has been developed. The model describes the rate of radionuclide release from depressurized rods and the rate of nuclear fuel fission processes in the vicinity of defects. The model and results of analysis are illustrated by experimental and statistical data on depressurization of WWER (PWR) and RBMK (BWR) reactor fuel rods. Possibility to solve the problem of predicting defect propagation is considered. (author). 5 refs, 9 figs, 3 tabs

  4. 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

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

    International Nuclear Information System (INIS)

    Kim, Jihee; Kang, Hyun Gook; Chang, Soon Heung

    2015-01-01

    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

  6. 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.

  7. 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...

  8. 78 FR 41684 - Special Conditions: Embraer S.A. Model EMB-550 Airplanes, Sudden Engine Stoppage

    Science.gov (United States)

    2013-07-11

    ...-tail empennage. The primary structure is metal with composite empennage and control surfaces. The Model..., Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue SW., Renton, Washington... more-critical airframe supporting structure. Applicability As discussed above, these special conditions...

  9. Leveraging model legume information to find candidate genes for soybean sudden death syndrome using the legume information system.

    Science.gov (United States)

    Gonzales, Michael D; Gajendran, Kamal; Farmer, Andrew D; Archuleta, Eric; Beavis, William D

    2007-01-01

    Comparative genomics is an emerging and powerful approach to achieve crop improvement. Using comparative genomics, information from model plant species can accelerate the discovery of genes responsible for disease and pest resistance, tolerance to plant stresses such as drought, and enhanced nutritional value including production of anti-oxidants and anti-cancer compounds. We demonstrate here how to use the Legume Information System for a comparative genomics study, leveraging genomic information from Medicago truncatula (barrel medic), the model legume, to find candidate genes involved with sudden death syndrome (SDS) in Glycine max (soybean). Specifically, genetic maps, physical maps, and annotated tentative consensus and expressed sequence tag (EST) sequences from G. max and M. truncatula can be compared. In addition, the recently published M. truncatula genomic sequences can be used to identify M. truncatula candidate genes in a genomic region syntenic to a quantitative trait loci region for SDS in soybean. Genomic sequences of candidate genes from M. truncatula can then be used to identify ESTs with sequence similarities from soybean for primer design and cloning of potential soybean disease causing alleles.

  10. 77 FR 58970 - Special Conditions: Embraer S.A. Model EMB-550 Airplanes, Sudden Engine Stoppage

    Science.gov (United States)

    2012-09-25

    ... primary structure is metal with composite empennage and control surfaces. The Model EMB-550 airplane is...: Cindy Ashforth, FAA, International Branch, ANM-116, Transport Airplane Directorate, Aircraft... conditions numbers 3 and 4, below) could allow some deformation in the engine-supporting structure (ultimate...

  11. Sudden transition from equilibrium stability to chaotic dynamics in a cautious tâtonnement model

    International Nuclear Information System (INIS)

    Foroni, I.; Avellone, A.; Panchuk, A.

    2016-01-01

    Discrete time price adjustment processes may fail to converge and may exhibit periodic or even chaotic behavior. To avoid large price changes, a version of the discrete time tâtonnement process for reaching an equilibrium in a pure exchange economy based on a cautious updating of the prices has been proposed two decades ago. This modification leads to a one dimensional bimodal piecewise smooth map, for which we show analytically that degenerate bifurcations and border collision bifurcations play a fundamental role for the asymptotic behavior of the model. (paper)

  12. AP1000 station blackout study with and without depressurization using RELAP5/SCDAPSIM

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, A.K. [Nuclear Engineering and Technology Program, Indian Institute of Technology, Kanpur 208016 (India); Allison, C. [Innovative Systems Software Idaho Falls, ID 83406 (United States); Khanna, A., E-mail: akhanna@iitk.ac.in [Nuclear Engineering and Technology Program, Indian Institute of Technology, Kanpur 208016 (India); Munshi, P. [Nuclear Engineering and Technology Program, Indian Institute of Technology, Kanpur 208016 (India)

    2016-10-15

    Highlights: • A representative RELAP5/SCDAPSIM model of AP1000 has been developed. • Core is modeled using SCDAP. • A SBO for the AP1000 has been simulated for high pressure (no depressurization) and low pressure (depressurization). • Significant differences in the damage progression have been observed for the two cases. • Results also reinforced the fact that surge line fails before vessel failure in case of high pressure scenario. - Abstract: Severe accidents like TMI-2, Chernobyl, Fukushima made it inevitable to analyze station blackout (SBO) for all the old as well as new designs although it is not a regulatory requirement in most of the countries. For such improbable accidents, a SBO for the AP1000 using RELAP5/SCDAPSIM has been simulated. Many improvements have been made in fuel damage progression models of SCDAP after the Fukushima accident which are now being tested for the new reactor designs. AP1000 is a 2-loop pressurized water reactor (PWR) with all the emergency core cooling systems based on natural circulation. Its core design is very similar to 3-loop PWR with 157 fuel assemblies. The primary circuit pumps, pressurizer and steam generators (with necessary secondary side) are modeled using RELAP5. The core has been divided into 20 axial nodes and 6 radial rings; the corresponding six groups of assemblies have been modeled as six pipe components with proportionate flow area. Fuel assemblies are modeled using SCDAP fuel and control components. SCDAP has 2d-heat conduction and radiative heat transfer, oxidation and complete severe fuel damage progression models. The final input deck achieved all the steady state thermal hydraulic conditions comparable to the design control document of AP1000. To quantify the core behavior, under unavailability of all safety systems, various time profiles for SBO simulations @ high pressure and low pressure have been compared. This analysis has been performed for 102% (3468 MWt) of the rated core power. The

  13. Sudden future singularities in quintessence and scalar-tensor quintessence models

    Science.gov (United States)

    Lymperis, A.; Perivolaropoulos, L.; Lola, S.

    2017-10-01

    We demonstrate analytically and numerically the existence of geodesically complete singularities in quintessence and scalar-tensor quintessence models with scalar field potential of the form V (ϕ )˜|ϕ |n with 0 equations and ts is the time of the singularity. In the case of quintessence we find q =n +2 (i.e. 2 equation of state w =p/ρ , is present. We find that the strength of the singularity (value of q ) remains unaffected by the presence of a perfect fluid. The linear and quadratic terms in (ts-t ) that appear in the expansion of the scale factor around ts are subdominant for the diverging derivatives close to the singularity, but can play an important role in the estimation of the Hubble parameter. Using the analytically derived relations between these terms, we derive relations involving the Hubble parameter close to the singularity, which may be used as observational signatures of such singularities in this class of models. For quintessence with matter fluid, we find that close to the singularity H ˙=3/2 Ω0 m(1 +zs)3-3 H2. These terms should be taken into account when searching for future or past time such singularities, in cosmological data.

  14. Sudden transition from equilibrium stability to chaotic dynamics in a cautious tâtonnement model

    International Nuclear Information System (INIS)

    Foroni, Ilaria; Avellone, Alessandro; Panchuk, Anastasiia

    2015-01-01

    Tâtonnement processes are usually interpreted as auctions, where a fictitious agent sets the prices until an equilibrium is reached and the trades are made. The main purpose of such processes is to explain how an economy comes to its equilibrium. It is well known that discrete time price adjustment processes may fail to converge and may exhibit periodic or even chaotic behavior. To avoid large price changes, a version of the discrete time tâtonnement process for reaching an equilibrium in a pure exchange economy based on a cautious updating of the prices has been proposed two decades ago. This modification leads to a one dimensional bimodal piecewise smooth map, for which we show analytically that degenerate bifurcations and border collision bifurcations play a fundamental role for the asymptotic behavior of the model.

  15. Unsteady Two-Dimensional Multi physical Simulation on the Sudden Contact of Pressure Tube and Calandria Tube in the Moderator Model for PHWR

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Semyong [Kunsan National Univ., Gunsan (Korea, Republic of); Kim, Hyoung Tae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    To limit the subcooling for the avoidance of dryout condition in a CANDU reactor, a suitable experiment should be proposed such as Ref. In this study, we simulated this experiment in 2-D with COMSOL Multi physics. A benchmark experiment model based on the Calandria moderator system of the CANDU reactor has been reduced to an ideal concentric 2-D computational model. A plastic deformation model is introduced, based on the creeping model in CATHENA code. The result shows a sudden inflation and contact of PT and CT in a very short time of milliseconds.

  16. Sudden death victims

    NARCIS (Netherlands)

    Ceelen, Manon; van der Werf, Christian; Hendrix, Anneke; Naujocks, Tatjana; Woonink, Frits; de Vries, Philip; van der Wal, Allard; Das, Kees

    2015-01-01

    The goal of this study was to ascertain accordance between cause of death established by the forensic physician and autopsy results in young sudden death victims in the Netherlands. Sudden death victims aged 1-45 years examined by forensic physicians operating in the participating regions which also

  17. 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.

  18. CNTB program for the analysis of partially mixed containment atmospheres during depressurization events

    International Nuclear Information System (INIS)

    Landoni, J.A.

    1979-07-01

    This program describes the analytical models for the CNTB computer program, which is permanently filed in the archive library of the General Atomic (GA) San Diego Data Center under reference number THSD-2699. Developed during the last four years, this computer program has been successfully applied in its presented form to the type of containment atmosphere transients illustrated in this report. For example, the CNTB computer program is applicable (1) to the design basis depressurization accident (DBDA) to determine the effect of the partial mixing on the containment atmospheric peak pressure (known as nonmixing penalty) and (2) for Class 9 accidents, such as the loss of forced circulation (LOFC), for the AIPA Phase I studies. The capability of the CNTB computer program has been substantially improved over its precursor, the CONTEMPT-G computer program, to predict the thermodynamic behavior of the containment atmosphere during helium releases, assuming partial mixing of the original air with the effluent and to predict the amount of the environmental leaks under closed and open containment conditions. In addition, the CNTB computer program running times are considerably below the ones required for the CONTEMPT-G computer program. Computational solution of the variable parameters in the containment atmosphere is effected by an iterative technique, while the temperatures for its boundaries are obtained by finite differences. The CNTB computer program, written in FORTRAN V, has been implemented at GA on the UNIVAC 1110 computer

  19. 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.

    2013-01-01

    SUMMARY 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::VHLfl/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. PMID:22977222

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

    Directory of Open Access Journals (Sweden)

    Marianne T. Neary

    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::VHLfl/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.

  1. 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...

  2. 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...

  3. The initial phase of sudden releases of superheated liquid

    International Nuclear Information System (INIS)

    Schmidli, J.

    1994-04-01

    The catastrophic failure of a pressure vessel containing a liquefied substance, leading to an instantaneous release of its whole contents is considered as one of the major technological hazards. Due to the rapid depressurization caused by vessel failure, the fluid becomes superheated and unstable. Part of the fluid will evaporate using its internal energy and the two-phase mixture forming will be accelerated. This flashing process can be very violent, as experiments and incidents actually happened have shown. In the past, a number of dispersion models were developed to predict the history of an instantaneous release. In most of these models the source term is considered to be a gas volume at rest and not a rapidly expanding aerosol, as could be observed. Furthermore, it is usually assumed that all of the remaining fluid is entrained into the expanding cloud and nothing is deposited on the ground to form a pool. This work concentrates on the initial phase of the sudden release of superheated liquids with the aim to gain a better understanding of the flashing process and of the physical mechanisms involved, leading to a reliable prediction of the source term. Therefore, more than 400 experiments with propane, butane, refrigerant 12 and 114 were conducted. The experiments were initiated by shattering spherical glass flasks of different sizes. The main parameters varied were the liquid superheat and the filling level of the vessel. Using high-speed video and movie recordings and very fast responding measurement devices, it was possible to study the initial phase of such releases during which gravity plays no role. For sufficiently large released internal energy, the initial evolution of the release was always spherical with a constant radial expansion velocity during he first milliseconds until instabilities appeared at the surface of the droplet/vapor cloud that was formed. For all the experimental conditions, the fraction of the initial liquid falling on the ground

  4. RECOMMENDED SUB-SLAB DEPRESSURIZATION SYSTEMS DESIGN STANDARD OF THE FLORIDA RADON RESEARCH PROGRAM

    Science.gov (United States)

    The report recommends sub-slab depressurization systems design criteria to the State of Florida's Department of Community Affairs for their building code for radon resistant houses. Numerous details are set forth in the full report. Primary criteria include: (1) the operating soi...

  5. ENGINEERING DESIGN CRITERIA FOR SUB-SLAB DEPRESSURIZATION SYSTEMS IN LOW-PERMEABILTY SOLIDS

    Science.gov (United States)

    The report describes the development of engineering design criteria for the successful design, installation, and operation of sub-slab depressurization systems, based on radon (Rn) mitigation experience on 14 slab-on-grade houses in South Central Florida. The Florida houses are c...

  6. 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)

  7. A depressurization assistance control based on the posture of a seated patient on a wheelchair.

    Science.gov (United States)

    Chugo, Daisuke; Fujita, Kazuya; Sakaida, Yuki; Yokota, Sho; Takase, Kunikatsu

    2011-01-01

    For reducing the risk of pressure sore caused by long period sitting on a wheelchair, we develop a depressurization motion assistance system which is low cost and suitable for practical use. Our developing system consists of a seating cushion which the patient sits on and four air cells which can lift or incline the seating cushion. Each air cell is actuated by small air compressor, which can drive using batteries on the wheelchair respectively, and each compressor has a pressure sensor on its body. In this paper, our key ideas are two topics. One topic is mechanical design for practical use. We realize thin mechanism which enables easy implementation to the general wheelchair. For realizing this thinly design, we develop the tilt mechanism using elasticity of acrylic resin and the controller which uses only pressure sensors for estimating its lifting height and inclination. The other topic is assistance control scheme based on the patient's depressurization operation for increasing a rehabilitation performance. For realizing the proposed control scheme, we analyze the hip depressurization operation by the nursing specialists and use its results for estimating the patient's condition. Using our system, the patient can depressurize by his own will on the general wheelchair easily. The performance of our system is verified by experiments using our prototype. © 2011 IEEE

  8. Perspectives on Severe Accident Management by Depressurization and External Water Injection under Extended SBO Conditions

    International Nuclear Information System (INIS)

    Seol, Wookcheol; Park, Jongwoon

    2014-01-01

    Three major issues of severe accident management guideline (SAMG) after this sort of extended SBO would be depressurization of the primary system, external water injection and hydrogen management inside a containment. Under this situation, typical SAM actions would be depressurization and external water delivery into the core. However, limited amount of external water would necessitate optimization between core cooling, containment integrity and fission product removal. In this paper, effects of SAM actions such as depressurization and external water injection on the reactor and containment conditions after extended SBO are analyzed using MAAP4 code. Positive and negative aspects are discussed with respect to core cooling and fission product retention inside a primary system. Conclusions are made as following: Firstly, early depressurization action itself has two-faces: positive with respect to delay of the reactor vessel failure but negative with respect to the containment failure and fission product retention inside the primary system. Secondly, in order to prevent containment overpressure failure after external water injection, re-closing of PORV later should be considered in SAM, which has never been considered in the previous SAMG. Finally, in case of external water injection, the flow rate should be optimized considering not only the cooling effect but also the long term fission product retention inside the primary system

  9. 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.

  10. Application of linear and non-linear low-Re k-ε models in two-dimensional predictions of convective heat transfer in passages with sudden contractions

    International Nuclear Information System (INIS)

    Raisee, M.; Hejazi, S.H.

    2007-01-01

    This paper presents comparisons between heat transfer predictions and measurements for developing turbulent flow through straight rectangular channels with sudden contractions at the mid-channel section. The present numerical results were obtained using a two-dimensional finite-volume code which solves the governing equations in a vertical plane located at the lateral mid-point of the channel. The pressure field is obtained with the well-known SIMPLE algorithm. The hybrid scheme was employed for the discretization of convection in all transport equations. For modeling of the turbulence, a zonal low-Reynolds number k-ε model and the linear and non-linear low-Reynolds number k-ε models with the 'Yap' and 'NYP' length-scale correction terms have been employed. The main objective of present study is to examine the ability of the above turbulence models in the prediction of convective heat transfer in channels with sudden contraction at a mid-channel section. The results of this study show that a sudden contraction creates a relatively small recirculation bubble immediately downstream of the channel contraction. This separation bubble influences the distribution of local heat transfer coefficient and increases the heat transfer levels by a factor of three. Computational results indicate that all the turbulence models employed produce similar flow fields. The zonal k-ε model produces the wrong Nusselt number distribution by underpredicting heat transfer levels in the recirculation bubble and overpredicting them in the developing region. The linear low-Re k-ε model, on the other hand, returns the correct Nusselt number distribution in the recirculation region, although it somewhat overpredicts heat transfer levels in the developing region downstream of the separation bubble. The replacement of the 'Yap' term with the 'NYP' term in the linear low-Re k-ε model results in a more accurate local Nusselt number distribution. Moreover, the application of the non-linear k

  11. 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'.

  12. 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…

  13. The sudden death and sudden birth of quantum discord.

    Science.gov (United States)

    Xia, Wei; Hou, Jin-Xing; Wang, Xiao-Hui; Liu, Si-Yuan

    2018-03-28

    The interaction of quantum system and its environment brings out abundant quantum phenomenons. The sudden death of quantum resources, including entanglement, quantum discord and coherence, have been studied from the perspective of quantum breaking channels (QBC). QBC of quantum resources reveal the common features of quantum resources. The definition of QBC implies the relationship between quantum resources. However, sudden death of quantum resources can also appear under some other quantum channels. We consider the dynamics of Bell-diagonal states under a stochastic dephasing noise along the z-direction, and the sudden death and sudden birth of quantum discord are investigated. Next we explain this phenomenon from the geometric structure of quantum discord. According to the above results, the states with sudden death and sudden birth can be filtered in three-parameter space. Then we provide two necessary conditions to judge which kind of noise channels can make Bell-diagonal states sudden death and sudden birth. Moreover, the relation between quantum discord and coherence indicates that the sudden death and sudden birth of quantum discord implies the sudden death and sudden birth of coherence in an optimal basis.

  14. 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.

  15. Compound heterozygous KCNQ1 mutations (A300T/P535T) in a child with sudden unexplained death: Insights into possible molecular mechanisms based on protein modeling.

    Science.gov (United States)

    Antúnez-Argüelles, Erika; Rojo-Domínguez, Arturo; Arregui-Mena, Ana Leticia; Jacobo-Albavera, Leonor; Márquez, Manlio Fabio; Iturralde-Torres, Pedro; Villarreal-Molina, María Teresa

    2017-09-05

    Sudden death in a child is a devastating event with important medical implications for surviving relatives. Because it may be the first manifestation of unknown inherited cardiac disease, molecular autopsy can be helpful to determine the cause of death and identify at risk family members. The aim of the study was to perform a molecular autopsy in a seven year-old girl with sudden unexplained death, to find evidence supporting the possible pathogenicity of mutations identified in inherited cardiac disease genes, and to clinically and genetically assess first-degree relatives. DNA from the index case was extracted from umbilical cord cells stored at birth, and DNA of first-degree relatives from blood samples. Targeted sequencing was performed using a Haloplex design including 81 cardiogenes. Possible functional consequences of the mutations were analyzed using protein modeling and structural mobility analyses. The child was compound heterozygous for KCNQ1 variants p.Ala300Thr and p.Pro535Thr. Ala300Thr is known to cause long QT syndrome in the homozygous state, while Pro535Thr is novel and of unknown clinical significance. The father and sibling were Ala300Thr heterozygous, and had normal QTc intervals at rest and during exercise. The asymptomatic mother was heterozygous for Pro535Thr, and showed borderline QTc at rest, but prolonged QTc during exercise. Protein modeling predicted that Ala300Thr alters the mobility profile of the Kv7.1 tetramer and Thr535 disrupts a calmodulin-binding site, probably causing co-assembly or trafficking defects of the mutant monomer. Altogether, the evidence strongly suggests that this child was affected with a recessive form of Romano Ward syndrome. Copyright © 2017. Published by Elsevier B.V.

  16. A real-time, dynamic early-warning model based on uncertainty analysis and risk assessment for sudden water pollution accidents.

    Science.gov (United States)

    Hou, Dibo; Ge, Xiaofan; Huang, Pingjie; Zhang, Guangxin; Loáiciga, Hugo

    2014-01-01

    A real-time, dynamic, early-warning model (EP-risk model) is proposed to cope with sudden water quality pollution accidents affecting downstream areas with raw-water intakes (denoted as EPs). The EP-risk model outputs the risk level of water pollution at the EP by calculating the likelihood of pollution and evaluating the impact of pollution. A generalized form of the EP-risk model for river pollution accidents based on Monte Carlo simulation, the analytic hierarchy process (AHP) method, and the risk matrix method is proposed. The likelihood of water pollution at the EP is calculated by the Monte Carlo method, which is used for uncertainty analysis of pollutants' transport in rivers. The impact of water pollution at the EP is evaluated by expert knowledge and the results of Monte Carlo simulation based on the analytic hierarchy process. The final risk level of water pollution at the EP is determined by the risk matrix method. A case study of the proposed method is illustrated with a phenol spill accident in China.

  17. Good news is bad news: Leverage cycles and sudden stops

    OpenAIRE

    Akinci, Ozge; Chahrour, Ryan

    2015-01-01

    We show that a model with imperfectly forecastable changes in future productivity and an occasionally binding collateral constraint can match a set of stylized facts about “sudden stop” events. “Good” news about future productivity raises leverage during times of expansion, increasing the probability that the constraint binds, and a sudden stop occurs, in future periods. The economy exhibits a boom period in the run-up to the sudden stop, with output, consumption, and investment all above tre...

  18. Two-phase mixture level swell and liquid entrainment/off-take in a vessel during rapid depressurization

    International Nuclear Information System (INIS)

    Kim, Chang Hyun

    2004-02-01

    An experimental study has been performed to analyze the two-phase mixture level swell and the liquid entrainment/off-take through the break in a vessel, which are important phenomena to determine the bleed capacity of the Safety Depressurization System (SDS) of Korea Advanced Power Reactor 1400 (APR1400). Three separate experiments are performed in this study: (a) the depressurization and two-phase mixture level swell experiment: (b) the two-phase mixture level measurement experiment: (c) the liquid entrainment and off-take experiment. A series of experiments has been performed using a scaled pressurized vessel in various depressurization conditions to analyze the two-phase mixture level swell and the liquid entrainment/off-take phenomena from the two-phase mixture surface in the first experiment. The test parameters are the initial pressure (10 - 38.75bars), the initial water level (43.7% - 80.0% of full height), the orifice inner diameter (10mm, 17.5mm, and 20mm). The liquid off-take takes place in certain experimental conditions. The measured parameters in the present experiments are axial void fraction distributions, pressures, temperatures in the test vessel, and the mixture density and mass flowrate through the discharge pipe. An assessment of RELAP5/MOD3 code with the present experimental data has been performed. With appropriate nodalization and time step, RELAP5/MOD3 showed reasonable agreement with the present experimental data for the gradual depressurization without liquid off-take. In the case that the off-take takes place, however, RELAP5/MOD3 under-predicts the amount of liquid entrainment/off-take during depressurization. In the second experiment, an assessment of an ultrasonic sensor and a two-wire type capacitance probe for the two-phase mixture level measurement has been performed under the same experimental conditions to adopt an appropriate measurement method for the two-phase mixture level swell and to investigate pool void fraction by the

  19. Assessment of IRI-2012, NeQuick-2 and IRI-Plas 2015 models with observed equatorial ionization anomaly in Africa during 2009 sudden stratospheric warming event

    Science.gov (United States)

    Bolaji, O. S.; Oyeyemi, E. O.; Adewale, A. O.; Wu, Q.; Okoh, D.; Doherty, P. H.; Kaka, R. O.; Abbas, M.; Owolabi, C.; Jidele, P. A.

    2017-11-01

    In Africa, we assessed the performance of all the three options of International Reference Ionosphere 2012, IRI-2012 (i.e. IRI-2001, IRI-2001COR and IRI-NeQuick), NeQuick-2 and IRI-Plas 2015 models prior to and during 2009 sudden stratospheric warming (SSW) event to predict equatorial ionization anomaly (EIA) crest locations and their magnitudes using total electron content (TEC) from experimental records of Global Positioning System (GPS). We confirmed that the IRI-Plas 2015 that appeared as the best compared to all of the models as regard prediction of the EIA crest locations in the northern hemisphere of Africa is due to discontinuities in the GPS data between ∼8° N and 22° N. As regard the predictions of EIA crest magnitudes and the location of EIA crests in the southern hemisphere of Africa, they are not present in all the models. The NeQuick-2 model does not have the capability to predict either the EIA crest location in the northern or southern hemisphere. The SSW effect on the low latitude was able to modify a single EIA crest to pre-noon and post noon EIA crests in the northern hemisphere during the SSW peak phase and significantly reduced the GPS TEC magnitudes over the hemispheres as well. These SSW effects and delays of plasma transportation to higher latitudes in GPS TEC were absent in all the models. For future improvements of IRI-2012, NeQuick-2 and IRI-Plas 2015 models, SSW conditions should be included in order to characterize the effect of lower atmosphere on the ionosphere. The EIA trough modeling is only present in IRI-2001COR and IRI-2001NeQuick options. In the middle latitude, all the model could not predict the location of highest TEC magnitudes found at RBAY (Richardsbay, South Africa).

  20. Sudden flaccid paralysis

    OpenAIRE

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

    2015-01-01

    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 ...

  1. Strategies for control of sudden oak death in Humboldt County-informed guidance based on a parameterized epidemiological model

    Science.gov (United States)

    João A. N. Filipe; Richard C. Cobb; David M. Rizzo; Ross K. Meentemeyer; Christopher A.. Gilligan

    2010-01-01

    Landscape- to regional-scale models of plant epidemics are direly needed to predict largescale impacts of disease and assess practicable options for control. While landscape heterogeneity is recognized as a major driver of disease dynamics, epidemiological models are rarely applied to realistic landscape conditions due to computational and data limitations. Here we...

  2. Distillability Sudden Birth of Entanglement for Qutrit-Qutrit Systems

    International Nuclear Information System (INIS)

    Huang Jiang; Ali Mazhar

    2014-01-01

    We report the sudden appearance of distillability between two statistically independent reservoirs modelled as qutrit-qutrit systems. This feature of bipartite quantum systems is different from the previously observed phenomenon of entanglement sudden birth. It is found that the states of reservoirs first become bound entangled, thus exhibiting entanglement sudden birth, consequently followed by the sudden birth of distillability, and it is shown that whenever distillability is lost abruptly from principal system, it also necessarily appears abruptly among reservoirs' degrees of freedom. This surprising observation reflects yet another peculiarity of dynamical aspects of quantum entanglement

  3. Sudden Cardiac Death

    DEFF Research Database (Denmark)

    Risgaard, Bjarke; Winkel, Bo Gregers; Jabbari, Reza

    2017-01-01

    Objectives This study sought to describe the use of pharmacotherapy in a nationwide cohort of young patients with sudden cardiac death (SCD). Background Several drugs have been associated with an increased risk of SCD and sudden arrhythmic death syndrome (SADS). It remains unclear how....... Autopsy was performed in 55%. Overall, 58% of SCD cases (n = 786) received at least 1 drug within 90 days before death. The most common drugs were analgesic drugs (n = 239; 18%), antihypertensive drugs (n = 234; 17%), and antibiotic drugs (n = 218; 16%). After multivariable adjustment, prescription...... of “brugadogenic” drugs or >1 QT-prolonging drug was associated with an increased risk of SADS compared with explained SCD (odds ratio: 2.16 [95% confidence interval: 1.12 to 4.17] and 2.91 [95% confidence interval: 1.46 to 5.81], respectively). Conclusions Pharmacotherapy was identified in 58% of the SCD cases...

  4. Rapid depressurization event analysis in BWR/6 using RELAP5 and contain

    Energy Technology Data Exchange (ETDEWEB)

    Mueftueoglu, A.K.; Feltus, M.A. [Pennsylvania State Univ., University Park, PA (United States)

    1995-09-01

    Noncondensable gases may become dissolved in Boiling Water Reactor (BWR) water level instrumentation during normal operations. Any dissolved noncondensable gases inside these water columns may come out of solution during rapid depressurization events, and displace water from the reference leg piping resulting in a false high level. These water level errors may cause a delay or failure in actuation, or premature shutdown of the Emergency Core Cooling System. (ECCS). If a rapid depressurization causes an erroneously high water level, preventing automatic ECCS actuation, it becomes important to determine if there would be other adequate indications for operator response and other signals for automatic actuation such as high drywell pressure. It is also important to determine the effect of the level signal on ECCS operation after it is being actuated. The objective of this study is to determine the detailed coupled containment/NSSS response during this rapid depressurization events in BWR/6. The selected scenarios involve: (a) inadvertent opening of all ADS valves, (b) design basis (DB) large break loss of coolant accident (LOCA), and (c) main steam line break (MSLB). The transient behaviors are evaluated in terms of: (a) vessel pressure and collapsed water level response, (b) specific transient boundary conditions, (e.g., scram, MSIV closure timing, feedwater flow, and break blowdown rates), (c) ECCS initiation timing, (d) impact of operator actions, (e) whether indications besides low-low water level were available. The results of the analysis had shown that there would be signals to actuate ECCS other than low reactor level, such as high drywell pressure, low vessel pressure, high suppression pool temperature, and that the plant operators would have significant indications to actuate ECCS.

  5. Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, J.; Moridis, G.J.; Grover, T.; Collett, T.

    2009-02-01

    In this simulation study, we analyzed the geomechanical response during depressurization production from two known hydrate-bearing permafrost deposits: the Mallik (Northwest Territories, Canada) deposit and Mount Elbert (Alaska, USA) deposit. Gas was produced from these deposits at constant pressure using horizontal wells placed at the top of a hydrate layer (HL), located at a depth of about 900 m at the Mallik and 600 m at the Mount Elbert. The simulation results show that general thermodynamic and geomechanical responses are similar for the two sites, but with substantially higher production and more intensive geomechanical responses at the deeper Mallik deposit. The depressurization-induced dissociation begins at the well bore and then spreads laterally, mainly along the top of the HL. The depressurization results in an increased shear stress within the body of the receding hydrate and causes a vertical compaction of the reservoir. However, its effects are partially mitigated by the relatively stiff permafrost overburden, and compaction of the HL is limited to less than 0.4%. The increased shear stress may lead to shear failure in the hydrate-free zone bounded by the HL overburden and the downward-receding upper dissociation interface. This zone undergoes complete hydrate dissociation, and the cohesive strength of the sediment is low. We determined that the likelihood of shear failure depends on the initial stress state as well as on the geomechanical properties of the reservoir. The Poisson's ratio of the hydrate-bearing formation is a particularly important parameter that determines whether the evolution of the reservoir stresses will increase or decrease the likelihood of shear failure.

  6. 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.

  7. Specific subcortical structures are activated during seizure-induced death in a model of sudden unexpected death in epilepsy (SUDEP): A manganese-enhanced magnetic resonance imaging study.

    Science.gov (United States)

    Kommajosyula, Srinivasa P; Randall, Marcus E; Brozoski, Thomas J; Odintsov, Boris M; Faingold, Carl L

    2017-09-01

    Sudden unexpected death in epilepsy (SUDEP) is a major concern for patients with epilepsy. In most witnessed cases of SUDEP generalized seizures and respiratory failure preceded death, and pre-mortem neuroimaging studies in SUDEP patients observed changes in specific subcortical structures. Our study examined the role of subcortical structures in the DBA/1 mouse model of SUDEP using manganese-enhanced magnetic resonance imaging (MEMRI). These mice exhibit acoustically-evoked generalized seizures leading to seizure-induced respiratory arrest (S-IRA) that results in sudden death unless resuscitation is rapidly instituted. MEMRI data in the DBA/1 mouse brain immediately after acoustically-induced S-IRA were compared to data in C57 (control) mice that were exposed to the same acoustic stimulus that did not trigger seizures. The animals were anesthetized and decapitated immediately after seizure in DBA/1 mice and after an equivalent time in control mice. Comparative T1 weighted MEMRI images were evaluated using a 14T MRI scanner and quantified. We observed significant increases in activity in DBA/1 mice as compared to controls at previously-implicated auditory (superior olivary complex) and sensorimotor-limbic [periaqueductal gray (PAG) and amygdala] networks and also in structures in the respiratory network. The activity at certain raphe nuclei was also increased, suggesting activation of serotonergic mechanisms. These data are consistent with previous findings that enhancing the action of serotonin prevents S-IRA in this SUDEP model. Increased activity in the PAG and the respiratory and raphe nuclei suggest that compensatory mechanisms for apnea may have been activated by S-IRA, but they were not sufficient to prevent death. The present findings indicate that changes induced by S-IRA in specific subcortical structures in DBA/1 mice are consistent with human SUDEP findings. Understanding the changes in brain activity during seizure-induced death in animals may lead to

  8. 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.

  9. Epidemiological modeling of invasion in heterogeneous landscapes: Spread of sudden oak death in California (1990-2030)

    Science.gov (United States)

    R.K. Meentemeyer; N.J. Cunniffe; A.R. Cook; J.A.N. Filipe; R.D. Hunter; D.M. Rizzo; C.A. Gilligan

    2011-01-01

    The spread of emerging infectious diseases (EIDs) in natural environments poses substantial risks to biodiversity and ecosystem function. As EIDs and their impacts grow, landscape- to regional-scale models of disease dynamics are increasingly needed for quantitative prediction of epidemic outcomes and design of practicable strategies for control. Here we use spatio-...

  10. 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.

  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. Sudden cardiac death and pump failure death prediction in chronic heart failure by combining ECG and clinical markers in an integrated risk model.

    Science.gov (United States)

    Ramírez, Julia; Orini, Michele; Mincholé, Ana; Monasterio, Violeta; Cygankiewicz, Iwona; Bayés de Luna, Antonio; Martínez, Juan Pablo; Laguna, Pablo; Pueyo, Esther

    2017-01-01

    Sudden cardiac death (SCD) and pump failure death (PFD) are common endpoints in chronic heart failure (CHF) patients, but prevention strategies are different. Currently used tools to specifically predict these endpoints are limited. We developed risk models to specifically assess SCD and PFD risk in CHF by combining ECG markers and clinical variables. The relation of clinical and ECG markers with SCD and PFD risk was assessed in 597 patients enrolled in the MUSIC (MUerte Súbita en Insuficiencia Cardiaca) study. ECG indices included: turbulence slope (TS), reflecting autonomic dysfunction; T-wave alternans (TWA), reflecting ventricular repolarization instability; and T-peak-to-end restitution (ΔαTpe) and T-wave morphology restitution (TMR), both reflecting changes in dispersion of repolarization due to heart rate changes. Standard clinical indices were also included. The indices with the greatest SCD prognostic impact were gender, New York Heart Association (NYHA) class, left ventricular ejection fraction, TWA, ΔαTpe and TMR. For PFD, the indices were diabetes, NYHA class, ΔαTpe and TS. Using a model with only clinical variables, the hazard ratios (HRs) for SCD and PFD for patients in the high-risk group (fifth quintile of risk score) with respect to patients in the low-risk group (first and second quintiles of risk score) were both greater than 4. HRs for SCD and PFD increased to 9 and 11 when using a model including only ECG markers, and to 14 and 13, when combining clinical and ECG markers. The inclusion of ECG markers capturing complementary pro-arrhythmic and pump failure mechanisms into risk models based only on standard clinical variables substantially improves prediction of SCD and PFD in CHF patients.

  13. Sudden cardiac death and pump failure death prediction in chronic heart failure by combining ECG and clinical markers in an integrated risk model

    Science.gov (United States)

    Orini, Michele; Mincholé, Ana; Monasterio, Violeta; Cygankiewicz, Iwona; Bayés de Luna, Antonio; Martínez, Juan Pablo

    2017-01-01

    Background Sudden cardiac death (SCD) and pump failure death (PFD) are common endpoints in chronic heart failure (CHF) patients, but prevention strategies are different. Currently used tools to specifically predict these endpoints are limited. We developed risk models to specifically assess SCD and PFD risk in CHF by combining ECG markers and clinical variables. Methods The relation of clinical and ECG markers with SCD and PFD risk was assessed in 597 patients enrolled in the MUSIC (MUerte Súbita en Insuficiencia Cardiaca) study. ECG indices included: turbulence slope (TS), reflecting autonomic dysfunction; T-wave alternans (TWA), reflecting ventricular repolarization instability; and T-peak-to-end restitution (ΔαTpe) and T-wave morphology restitution (TMR), both reflecting changes in dispersion of repolarization due to heart rate changes. Standard clinical indices were also included. Results The indices with the greatest SCD prognostic impact were gender, New York Heart Association (NYHA) class, left ventricular ejection fraction, TWA, ΔαTpe and TMR. For PFD, the indices were diabetes, NYHA class, ΔαTpe and TS. Using a model with only clinical variables, the hazard ratios (HRs) for SCD and PFD for patients in the high-risk group (fifth quintile of risk score) with respect to patients in the low-risk group (first and second quintiles of risk score) were both greater than 4. HRs for SCD and PFD increased to 9 and 11 when using a model including only ECG markers, and to 14 and 13, when combining clinical and ECG markers. Conclusion The inclusion of ECG markers capturing complementary pro-arrhythmic and pump failure mechanisms into risk models based only on standard clinical variables substantially improves prediction of SCD and PFD in CHF patients. PMID:29020031

  14. 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. 2015 BMJ Publishing Group Ltd.

  15. 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

  16. Cardiac ion channelopathies and the sudden infant death syndrome

    NARCIS (Netherlands)

    Wilders, Ronald

    2012-01-01

    The sudden infant death syndrome (SIDS) causes the sudden death of an apparently healthy infant, which remains unexplained despite a thorough investigation, including the performance of a complete autopsy. The triple risk model for the pathogenesis of SIDS points to the coincidence of a vulnerable

  17. The sudden success of prose

    DEFF Research Database (Denmark)

    Mortensen, Lars Boje

    2017-01-01

    . It is also suggested that the exactly contemporary rise of French and Old Norse prose (c. 1200-1230) most probably is connected. The four literatures are each shown in chronological charts so as to visualize the timeline and the relation between poetic and prosaic works. The article furthermore reflects......The article presents a new model for understanding the sudden success of prose in four literatures: Greek, Latin, French and Old Norse. Through comparison and quantitative observations, and by focusing on the success of prose rather than its invention, it is shown that in all four cases two...... reading aloud) has been underplayed in previous scholarship mostly focused on authorial choices and invention. For two of the literatures (Greek, French) the fast dynamics of the rise of prose has already been identified and discussed, but for the two others (Latin, Old Norse), the observation is new...

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

    Science.gov (United States)

    Jun, Jonathan C.; Unnikrishnan, Dileep; Schneider, Hartmut; Kirkness, Jason; Schwartz, Alan R.; Smith, Philip L.; Polotsky, Vsevolod Y.

    2016-01-01

    Background 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. Methods 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. Results 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 (pCPAP-on and CPAP-off was 4.7 ± 2 and 20.4 ± 4.7 respectively (pCPAP depressurization also induced more awake (pCPAP during sleep led to deterioration of sleep architecture but only partial re-emergence of OSA. These observations suggest carryover effects of CPAP. PMID:26731735

  19. 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.

  20. Sudden Event Recognition: A Survey

    Directory of Open Access Journals (Sweden)

    Mohd Asyraf Zulkifley

    2013-08-01

    Full Text Available 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.

  1. 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

  2. Sudden flaccid paralysis

    Science.gov (United States)

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

    2015-01-01

    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 <0.01 mIU/L (normal range 0.35–4.94). Random urinary potassium was 8.8 mEq/L (normal range 12.5–62.5). The patient was admitted initially to intensive therapy unit and given intravenous potassium. His symptoms resolved within 24 h. He was diagnosed with thyrotoxic periodic paralysis. He was discharged on carbimazole and propanolol, and follow-up was arranged in the endocrinology clinic. PMID:25566931

  3. Sudden death in athletes.

    Science.gov (United States)

    Corrado, Domenico; Zorzi, Alessandro

    2017-06-15

    Competitive sports activity is associated with an increased risk of sudden cardiovascular death (SCD) in adolescents and young adults with clinically silent cardiovascular disorders. While in middle-aged/senior athletes atherosclerotic coronary artery disease accounts for the vast majority of SCDs, in young athletes the spectrum of substrates is wider and includes inherited (cardiomyopathies) and congenital (anomalous origin of coronary arteries) structural heart diseases. Inherited ion channel diseases have been implicated in SCDs occurring with an apparently normal heart at autopsy. Screening including the ECG allows identification of athletes affected by heart muscle diseases at a pre-symptomatic stage and may lead to reduction of the risk of SCD during sports. The use of modern criteria for interpretation of the ECG in the athlete offers the potential to improve the screening accuracy by reducing the number of false positives. Screening with exercise testing middle aged/senior athletes engaged in leisure sports activity is likely to be effective in patients with significant coronary risk factors, while it is not useful in low-risk subgroups. The availability of automated external defibrillator on the athletic field provides a "back-up" preventive strategy for unpredictable arrhythmic cardiac arrest, mostly occurring in patients with coronary artery diseases. Copyright © 2017. Published by Elsevier B.V.

  4. 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

  5. REFERENCE MANUAL FOR RASSMIT VERSION 2.1: SUB-SLAB DEPRESSURIZATION SYSTEM DESIGN PERFORMANCE SIMULATION PROGRAM

    Science.gov (United States)

    The report is a reference manual for RASSMlT Version 2.1, a computer program that was developed to simulate and aid in the design of sub-slab depressurization systems used for indoor radon mitigation. The program was designed to run on DOS-compatible personal computers to ensure ...

  6. Preliminary Assessment of Depressurization Performance of Reactor Building Spray dedicated to Severe Accident

    International Nuclear Information System (INIS)

    Park, Chang Hwan; Jo, Jae Sun; Yoon, Sun Hong

    2010-01-01

    In these days, the global demand for the nuclear power plant is gradually increasing and then it is encouraging to see the mood in which the possibility of exportation of Korean has been realized. According to this situation, the need for development of the country-tailored NPP is emerging because that there are some differences among the safety requirements of each country. Especially, European countries require relatively conservative safety criteria for the severe accident. Thus, development of a tactical NPP with the enhanced safety features dedicated to the severe accident is on the way. One of these safety features is the containment spray system dedicated to the severe accident. In this study, the depressurization capacity of the SA spray is assessed and the minimum capacity ensuring applicable performance is estimated with MAAP4 code. The reference plant for this analysis is chosen as APR1400

  7. Reactor containment depressurization and filtration equipment for use in the case of a serious accident

    International Nuclear Information System (INIS)

    L'Homme, A.

    1987-06-01

    A study was carried out under the aegis of the OECD into filtered vented containment systems which permit depressurization of the containment and filtration of the effluents released to the environment, in the event of a major accident with a pressurized water reactor (PWR) (or BWR or CANDU type reactors) involving core meltdown, with a view to minimizing the consequences. This paper describes the various systems examined which could possibly be used for this purpose. These comprised the French robust sand filtration system, the Swedish FILTRA system, the vacuum containment and discharge and emergency filtration system used by the CANDU plants of the Ontario-Hydro electricity company in Canada and the BWR pressure-suppression pounds. The positions of the various national authorities regarding incorporation of such systems into nuclear power plants, the design and technical principles underlying the systems, the procedures and criteria for their use and their advantages and disadvantages are examined [fr

  8. The Impact of Sudden Gains in Cognitive Behavioral Therapy for Posttraumatic Stress Disorder

    OpenAIRE

    Kelly, Kacie A.; Rizvi, Shireen L.; Monson, Candice M.; Resick, Patricia A.

    2009-01-01

    This study investigated sudden gains, i.e., rapid and stable improvements, in posttraumatic stress disorder (PTSD) symptoms that may occur in cognitive–behavioral therapy. Twenty-nine of 72 participants (39.2%) experienced a sudden gain during treatment. Mixed model ANOVAs analyzed sudden gains impact on clinician-rated PTSD symptom severity, patient-rated PTSD symptom severity, and patient-rated depressive symptom severity. Sudden gains in PTSD symptomology were associated with greater reduc...

  9. 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.

  10. 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.

  11. [Predicting value of 2014 European guidelines risk prediction model for sudden cardiac death (HCM Risk-SCD) in Chinese patients with hypertrophic cardiomyopathy].

    Science.gov (United States)

    Li, W X; Liu, L W; Wang, J; Zuo, L; Yang, F; Kang, N; Lei, C H

    2017-12-24

    Objective: To evaluate the predicting value of the 2014 European Society of Cardiology (ESC) guidelines risk prediction model for sudden cardiac death (HCM Risk-SCD) in Chinese patients with hypertrophic cardiomyopathy (HCM), and to explore the predictors of adverse cardiovascular events in Chinese HCM patients. Methods: The study population consisted of a consecutive 207 HCM patients admitted in our center from October 2014 to October 2016. All patients were followed up to March 2017. The 5-year SCD probability of each patient was estimated using HCM Risk-SCD model based on electrocardiogram, echocardiography and cardiac magnetic resonance (CMR) examination results. The primary, second, and composite endpoints were recorded. The primary endpoint included SCD and appropriate ICD therapy, identical to the HCM Risk-SCD endpoint. The second endpoint included acute myocardial infarction, hospitalization for heart failure, thrombus embolism and end-stage HCM. The composite endpoint was either the primary or the second endpoint. Patients were divided into the 3 categories according to 5-year SCD probability assessed by HCM Risk-SCD model: low risk grouprisk group ≥4% torisk group≥6%. Results: (1) Prevalence of endpoints: All 207 HCM patients completed the follow-up (350 (230, 547) days). During follow-up, 8 (3.86%) patients reached the primary endpoints (3 cases of SCD, 3 cases of survival after defibrillation, and 2 cases of appropriate ICD discharge); 21 (10.14%) patients reached the second endpoints (1 case of acute myocardial infarction, 16 cases of heart failure hospitalization, 2 cases of thromboembolism, and 2 cases of end-stage HCM). (2) Predicting value of HCM Risk-SCD model: Patients with primary endpoints had higher prevalence of syncope and intermediate-high risk of 5-year SCD, as compared to those without primary endpoints (both Pvalue of HCM Risk-SCD model: The low risk group included 122 patients (59%), the intermediate risk group 42 (20%), and the

  12. 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

  13. [Current concepts on sudden death].

    Science.gov (United States)

    Asensio, Enrique; Narváez, René; Dorantes, Joel; Oseguera, Jorge; Orea, Arturo; Hernández, PabloR; Rebollar, Verónica; Mont, Lluís; Brugada, Josep

    2005-01-01

    Sudden death is defined as the death occurring less than one hour before the onset of the patient's symptoms. It is a severe condition considered a public health issue in several countries and in ours, it accounts for 33 000 to 53 000 annual deaths mainly related to ischemic heart disease. The main cause of sudden death are severe ventricular arrhythmias, but determining what patients are at risk for such an episode is complex, that is why risk stratification is usually a low cost-effective intervention. In the present study, we describe different sudden death risk-stratification strategies. Different sudden death treatment strategies regarding general population have different success rates in different countries, nevertheless, among select high risk populations; the best therapy currently available is the automatic implantable cardioverter-defibrillator. We also discuss other treatment options. In Mexico it is deemed necessary to do an important effort for the early detection, prevention and treatment of sudden death in order to limit the consequences of this problem.

  14. Hypokalemia and sudden cardiac death

    DEFF Research Database (Denmark)

    Kjeldsen, Keld

    2010-01-01

    Worldwide, approximately three million people suffer sudden cardiac death annually. These deaths often emerge from a complex interplay of substrates and triggers. Disturbed potassium homeostasis among heart cells is an example of such a trigger. Thus, hypokalemia and, also, more transient......, drugs with a proven significant positive effect on mortality and morbidity rates in heart failure patients all increase plasma potassium concentration. Thus, it may prove beneficial to pay more attention to hypokalemia and to maintain plasma potassium levels in the upper normal range. The more at risk...... of fatal arrhythmia and sudden cardiac death a patient is, the more attention should be given to the potassium homeostasis....

  15. Development and evaluation of a new depressurization spillage test for residential gas-fired combustion appliances : final report

    International Nuclear Information System (INIS)

    Edwards, P.

    2005-07-01

    This paper presented a newly developed combustion depressurization spillage test for residential combustion appliances. The test uses carbon dioxide (CO 2 ) that is produced in the fuel combustion process as a tracer gas. The test accurately measures the amount of combustion spillage from residential combustion appliances and their venting systems when they operate at certain levels of depressurization. Seven commonly used gas-fired appliances were used to evaluate the new test as well as the appliances. These included 2 power-vented storage-tank water heaters, 1 mid-efficiency furnace, 2 high-efficiency condensing furnaces, and 2 direct-vent gas fireplaces. Tests were performed for each unit with the test room initially depressurized by 50 Pa compared with the pressure outside the room. If the combustion spillage exceeded 2 per cent, the test was repeated with the room depressurized by 20 Pa, and then by 5 Pa. Each appliance was operated for 5 minutes of burner operation during which time the burner fuel consumption, the concentration of CO 2 and the exhaust fan flow rate were monitored. Measurements were taken for 2 minutes following burner shut off. The amount of CO 2 that was released into the test room from the appliance and its venting system was determined from the measurements and then compared with the amount of CO 2 that would be produced by combustion of the fuel that was consumed during the test. The ratio of the 2 provided a direct measure of the combustion spillage of the appliance and its venting system. The study revealed that 3 products had undetectable levels of combustion spillage, 3 products had low, but measurable combustion spillage, and 1 product had significant combustion spillage. refs., tabs., figs

  16. 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.

  17. Evaluation of the need for a rapid depressurization capability for Combustion Engineering plants

    International Nuclear Information System (INIS)

    Marsh, L.; Liang, C.

    1984-12-01

    This report documents the NRC staff evaluation of the need for providing a rapid primary system depressurization capability, in particular by using a power-operated relief valve(s) (PORVs), in the current 3410-MWt and 3800-MWt classes of plants designed by Combustion Engineering (CE). The staff reviewed the responses of licensees, applicants, and vendors to staff questions, supplemented by independent analyses by the staff and its contractors. The staff review led to the conclusion that, on the basis of risk reduction and cost/benefit considerations, no overwhelming benefit would result from requiring the installation of PORVs in CE plants that currently do not have them. However, when other unquantifiable considerations regarding the potential benefits of a PORV are factored into the evaluation, it appears that more substantial benefits could be realized. Given the more comprehensive studies currently under way to resolve the generic unresolved safety issue, USI A-45, Decay Heat Removal Reliability, the staff concludes that the decision regarding PORVs for these CE plants should be deferred and incorporated into the technical resolution of USI A-45

  18. Sudden oak death online symposium

    Science.gov (United States)

    S.D. Cohen; J., eds Juzwik

    2003-01-01

    This symposium is being made available to all who have an interest in the recent appearance of Sudden Oak Death, a plant disease with the potential to severely impact nursery growers, shippers, the lumber and wood products industry, landscapers, government programs and others. Scientific presentations dealing with the current status of the disease and ongoing research...

  19. 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…

  20. Steroid Treatments Equally Effective Against Sudden Deafness

    Science.gov (United States)

    ... 6, 2011 Steroid Treatments Equally Effective Against Sudden Deafness Injecting steroids into the middle ear works just ... when it comes to restoring hearing for sudden deafness patients. This finding, the result of a large ...

  1. 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)

  2. 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

  3. Sudden death in eating disorders

    OpenAIRE

    Jáuregui-Garrido, Beatriz; Jáuregui-Lobera, Ignacio

    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...

  4. 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.

  5. 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 %.

  6. Temporal epidemiology of sudden oak death in Oregon

    Science.gov (United States)

    Ebba K. Peterson; Everett M. Hansen; Alan Kanaskie

    2015-01-01

    An effort to eradicate Phytophthora ramorum, causal agent of sudden oak death, has been underway since its discovery in Oregon forests. Using an information-theoretical approach, we sought to model yearly variation in the size of newly infested areas and dispersal distance. Maximum dispersal distances were best modeled by spring and winter...

  7. The Impact of Sudden Gains in Cognitive Behavioral Therapy for Posttraumatic Stress Disorder

    Science.gov (United States)

    Kelly, Kacie A.; Rizvi, Shireen L.; Monson, Candice M.; Resick, Patricia A.

    2009-01-01

    This study investigated sudden gains, i.e., rapid and stable improvements, in posttraumatic stress disorder (PTSD) symptoms that may occur in cognitive–behavioral therapy. Twenty-nine of 72 participants (39.2%) experienced a sudden gain during treatment. Mixed model ANOVAs analyzed sudden gains impact on clinician-rated PTSD symptom severity, patient-rated PTSD symptom severity, and patient-rated depressive symptom severity. Sudden gains in PTSD symptomology were associated with greater reductions in PTSD symptom severity for the avoidance/numbing and hyperarousal symptom clusters at posttreatment. By 6-month follow-up, the sudden gains group had maintained those reductions in symptoms, but the nonsudden gains group had achieved equal reductions in symptom severity. Participants experiencing sudden gains on PTSD measures had lower depression severity at posttreatment and follow-up. PMID:19637322

  8. Analysis of the primary system depressurization due to an 8-inch rupture in the hot leg during cooling down of the unit

    International Nuclear Information System (INIS)

    Serrano, M.A.B.; Silva, M.C. da

    1985-01-01

    A conservative analysis of total depressurization of the Angra-1 power plant is made. It was assumed that the plant's safety system was not activated and that the operator took no action to mitigate the transient's consequences. The results obtained showed that there is no damage in the core. The fuel remains under water up to the end of the depressurization. The containment is not damaged since the maximum pressure attained during the simulated accident stands bellow the activation point of the containment's spray system. (F.E.) [pt

  9. Risk factors and causes of sudden noncardiac death

    DEFF Research Database (Denmark)

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

    2015-01-01

    review of death certificates. Autopsy reports were collected. A multivariable logistic regression model was used to identify both clinical characteristics and risk factors associated with SNCD. RESULTS: We identified 1039 autopsied cases of sudden death, of which 286 (28%) were classified as SNCD...... 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.......3-2.3; OR 3.0, 95% CI 2.0-4.4; and OR 4.3, 95% CI 2.5-7.4, respectively). The most common cause of SNCD was pulmonary disease (n = 115 [40%]). CONCLUSION: Sudden death among individuals aged Risk factors were female sex, age, and the absence...

  10. Fragmentation of suddenly heated liquids

    International Nuclear Information System (INIS)

    Blink, J.A.

    1985-03-01

    Fragmentation of free liquids in Inertial Confinement Fusion reactors could determine the upper bound on reactor pulse rate. The x-ray ablated materials must cool and recondense to allow driver beam propagation. The increased surface area caused by fragmentation will enhance the cooling and condensation rates. Relaxation from the suddenly heated state will move a liquid into the negative pressure region under the liquid-vapor P-V dome. The lithium equation of state was used to demonstrate that neutron-induced vaporization uses only a minor fraction of the added heat, much less than would be required to drive the expansion. A 77% expansion of the lithium is required before the rapid vaporization process of spinodal decomposition could begin, and nucleation and growth are too slow to contribute to the expansion

  11. Sudden death during medical thoracoscopy.

    Science.gov (United States)

    Rocca, Gabriele; Pizzorno, Enrico; Tajana, Luca; Osculati, Antonio; Ventura, Francesco

    2014-01-01

    Medical thoracoscopy (or pleuroscopy) is a valuable diagnostic tool in patients with pleural pathology, being minimally invasive, inexpensive and relatively easy to learn. Complications may occur, depending on the complexity of the case, and mainly include broncho-pleural fistulas, chest infections, arrhythmia, severe hemorrhage due to blood vessel injury, and air or gas embolism. Death is very rare. The present report describes the peculiar case of a 72-year-old woman affected by a pleural empyema who suddenly and unexpectedly died during medical thoracoscopy. On autopsy, three small perforations of the right lung were found, without involvement of major vessels or bronchial ramifications. After a brief overview of medical thoracoscopy and its complications, the fatality and its possible pathophysiological mechanisms are analyzed through a review of the literature. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  12. Sudden Cardiac Death in Children. Part 1

    Directory of Open Access Journals (Sweden)

    Ye.V. Pshenichnaya

    2013-02-01

    Full Text Available This article presents the prevalence, terminology, classification of sudden cardiac death. A description of congenital structural heart diseases associated with a risk of sudden cardiac death is given. The issues of etiology and pathogenesis of life-threatening conditions are described in detail.

  13. Sudden Cardiac Death in Children. Part 2

    Directory of Open Access Journals (Sweden)

    Ye.V. Pshenichnaya

    2013-03-01

    Full Text Available This article deals with the dysplastic changes in musculo-valve structures of the heart, arrhythmias and conduction disorders, associated with a risk of sudden cardiac death. The diagnostic criteria for sudden cardiac death, the events of cardio-pulmonary resuscitation, prevention of life-threatening conditions in children are provided.

  14. 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…

  15. Source Test Report for the 205 Delayed Coking Unit Drum 205-1201 and Drum 205-1202 Depressurization Vents (Marathon Petroleum Company LLC)

    Science.gov (United States)

    The 2010 Source Test was performed during the atmospheric depressurization step of the delayed coking process prior to the removal of petroleum coke from the coke drum. The 205 DCU was operated under a variety of conditions during the 2010 Source Test.

  16. 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...

  17. DESIGN AND TESTING OF SUB-SLAB DEPRESSURIZATION FOR RADON MITIGATION IN NORTH FLORIDA HOUSES - PART I. PERFORMANCE AND DURABILITY - VOLUME 2. DATA APPENDICES

    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...

  18. Sudden bilateral hearing loss after organophosphate inhalation

    Directory of Open Access Journals (Sweden)

    Mehmet Akif Dundar

    2016-12-01

    Full Text Available 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. Keywords: Organophosphates, Hearing loss, Sudden

  19. Enzymatic hydrolysis of chitin pretreated by rapid depressurization from supercritical 1,1,1,2-tetrafluoroethane toward highly acetylated oligosaccharides.

    Science.gov (United States)

    Villa-Lerma, Guadalupe; González-Márquez, Humberto; Gimeno, Miquel; Trombotto, Stéphane; David, Laurent; Ifuku, Shinsuke; Shirai, Keiko

    2016-06-01

    The hydrolysis of chitin treated under supercritical conditions was successfully carried out using chitinases obtained by an optimized fermentation of the fungus Lecanicillium lecanii. The biopolymer was subjected to a pretreatment based on suspension in supercritical 1,1,1,2-tetrafluoroethane (scR134a), which possesses a critical temperature and pressure of 101°C and 40bar, respectively, followed by rapid depressurization to atmospheric pressure and further fibrillation. This methodology was compared to control untreated chitins and chitin subjected to steam explosion showing improved production of reducing sugars (0.18mg/mL), enzymatic hydrolysis and high acetylation (FA of 0.45) in products with degrees of polymerization between 2 and 5. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Development of a hybrid safety system: Actuation of the secondary automatic depressurization system at an early stage

    International Nuclear Information System (INIS)

    Nishimoto, Masae; Umezawa, Shigemitsu; Okabe, Kazuharu; Matsuoka, Tsuyoshi

    1996-01-01

    A Hybrid Safety System, which is an optimum combination of active and passive safety systems, has been developed in order to improve the safety, reliability and economic features of the next generation of PWRs. The passive safety systems include Automatic primary Depressurization System (ADS), Secondary Automatic Depressurization System (SADS), advanced accumulators, gravity injection system and so on. In this study the authors have improved the actuation logic of the passive safety systems. The original logic in the previous study actuates ADS at an early stage of an event such as a Loss-of-Coolant Accident (LOCA), and this is followed by the actuation of SADS. In this study they divide SADS into two systems. The first, small SADS, uses small valves corresponding to the relief valves of the conventional PWR plants. The second, large SADS, corresponds to the original SADS using multiple valves of large capacity. With the new logic, the passive systems are actuated during a typical small LOCA. Small LOCA analyses using several break areas were performed for a 1,400 MWe PWR plant with a Hybrid Safety System. The results predict that core uncovery does not occur in the case of a relatively small break area and that core heat removal during a small LOCA is improved in comparison with the analyses for conventional PWR plants, where the secondary pressure remains higher during the event. The results also predict that this new logic make it possible to reduce the ADS valve size and the actuation pressure setpoint of the passive safety systems

  1. Neurochemical Alterations in Sudden Unexplained Perinatal Deaths—A Review

    Directory of Open Access Journals (Sweden)

    Nazeer Muhammad

    2018-01-01

    Full Text Available Sudden unexpected perinatal collapse is a major trauma for the parents of victims. Sudden infant death syndrome (SIDS is unexpected and mysterious death of an apparently healthy neonate from birth till 1 year of age without any known causes, even after thorough postmortem investigations. However, the incidence of sudden intrauterine unexplained death syndrome (SIUDS is seven times higher as compared with SIDS. This observation is approximated 40–80%. Stillbirth is defined as death of a fetus after 20th week of gestation or just before delivery at full term without a known reason. Pakistan has the highest burden of stillbirth in the world. This basis of SIDS, SIUDS, and stillbirths eludes specialists. The purpose of this study is to investigate factors behind failure in control of these unexplained deaths and how research may go ahead with improved prospects. Animal models and physiological data demonstrate that sleep, arousal, and cardiorespiratory malfunctioning are abnormal mechanisms in SIUDS risk factors or in newborn children who subsequently die from SIDS. This review focuses on insights in neuropathology and mechanisms of SIDS and SIUDS in terms of different receptors involved in this major perinatal demise. Several studies conducted in the past decade have confirmed neuropathological and neurochemical anomalies related to serotonin transporter, substance P, acetylcholine α7 nicotine receptors, etc., in sudden unexplained fetal and infant deaths. There is need to focus more on research in this area to unveil the major curtain to neuroprotection by underlying mechanisms leading to such deaths.

  2. 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.

  3. 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...

  4. Prediction and Prevention of Sudden Cardiac Death.

    Science.gov (United States)

    Morin, Daniel P; Homoud, Munther K; Estes, N A Mark

    2017-12-01

    Sudden death is a major problem, with significant impact on public health. Many conditions predispose to sudden cardiac death and sudden cardiac arrest (SCA), foremost among them coronary artery disease, and an effective therapy exists in the form of the implantable cardioverter defibrillator. Risk stratification for SCA remains imperfect, especially for patients with nonischemic cardiomyopathy. Ongoing trials may make it easier to identify those at high risk, and potentially those at very low risk, in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Night terrors and sudden unexplained nocturnal death.

    Science.gov (United States)

    Melles, R B; Katz, B

    1988-06-01

    A high incidence of sudden unexplained nocturnal deaths has been reported among young Asian males. These deaths are known as Pokkuri in Japan, Bangungut in the Philippines and Sudden Unexplained Nocturnal Death in the United States. Post mortem analysis has demonstrated cardiac conduction defects in many of the victims. Careful review of the terminal events surrounding these deaths suggests that the victims suffered from night terrors. Night terrors are a sleep disorder characterized by vocalization, motor activity, a nonarousable state, and severe autonomic discharge. The proposed recognition of both night terrors and cardiac anomalies in these patients offers a pathophysiologic mechanism for their sudden death.

  6. Sudden unexpected death caused by stroke

    DEFF Research Database (Denmark)

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

    2018-01-01

    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...... contacted the healthcare system because of neurological symptoms, whereof one was suspected of having a stroke (6%). Conclusions Sudden death by stroke in children and young adults occurs primarily due to hemorrhagic stroke. We report a high frequency of neurological symptoms prior to sudden death by stroke....... Increased awareness among healthcare professionals towards stroke symptoms in children and young adults may lead to earlier detection of stroke, and thereby potentially lowering the incidence of sudden death by stroke....

  7. Sudden Arrhythmia Death Syndromes (SADS) Foundation

    Science.gov (United States)

    ... the Mayo Clinic are working together to develop machine learning technology to help prevent sudden death. • The Mayo ... you for your donation! Volunteer to Fight SADS! Overview of SADS Conditions Online Community SADS Online Support ...

  8. 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.

  9. Sudden Sensorineural Hearing Loss; Prognostic Factors

    OpenAIRE

    Arjun, Dass; Neha, Goel; Surinder K, Singhal; Ravi, Kapoor

    2015-01-01

    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, se...

  10. Sport and sudden death in children

    Directory of Open Access Journals (Sweden)

    L. M. Makarov

    2017-01-01

    Full Text Available The article presents data on contemporary views of the prevalence, causes, circumstances of sudden cardiac death, and its prevention measures in children and adolescents during sports activity. It notes a difficulty in defining the epidemiology of the above condition because the data are primarily based upon mass media news coverage. The incidence of sudden cardiac death is approximately 1 per 100,000 young athletes; more than 90% boys die. The sports, during which sudden cardiac death often occurs, include (both American and European football, basketball, and hockey. Sudden cardiac death due to cоmmоtio cordis (life-threatening cardiac arrhythmias resulting from a blow with a blunt instrument to the area of the heart during the vulnerable phase of the cardiac cycle is considered separately. Children who die suddenly during sports are frequently detected to have hypertrophic cardiomyopathy or myocarditis; but no changes are found in more than 50% of cases at autopsy, which is suggestive of primary arrhythmogenic death. The basis for prevention is the early detection of diseases that can cause sudden death during sports, regular examination, knowledge of ECG characteristics in athletes, and first aid techniques, including the use of automated external defibrillators.

  11. 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.

  12. 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

  13. An experimental study on effective depressurization actions for PWR vessel bottom small break LOCA with HPI failure and gas inflow (ROSA-V test SB-PV-04)

    International Nuclear Information System (INIS)

    Suzuki, Mitsuhiro; Takeda, Takeshi; Asaka, Hideaki; Nakamura, Hideo

    2006-03-01

    A small break loss-of-coolant accident (SBLOCA) experiment was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study effects of accident management (AM) measures on core cooling, which are important in case of total failure of high pressure injection (HPI) system during an SBLOCA at a pressurized water reactor (PWR). The LSTF is a full-height and 1/48 volume-scaled facility simulating a 4-loop Westing-house-type PWR (3423 MWt). The experiment, SB-PV-04, simulated a PWR vessel bottom SBLOCA with a rupture of ten instrument-tubes which is equivalent to 0.2% cold leg break. It is clarified that AM actions with steam generator (SG) rapid depressurization by fully opening relief valves and auxiliary feedwater supply are effective to avoid core uncovery by actuating the low pressure injection (LPI) system though the primary depressurization is degraded by non-condensable gas inflow to the primary loops from the accumulator injection system. The effective core cooling was established by the rapid depressurization which contributed to preserve larger primary coolant mass than in the previous experiment (SB-PV-03) which was conducted with smaller primary cooling rate of -55 K/h as AM actions. (author)

  14. Thermodynamic and depressurization experiments at an angular bellows under cyclic movement in helium at temperatures up to 10000C and at a pressure of 35 bars

    International Nuclear Information System (INIS)

    Lang, H.; Klas, E.; Schumacher, G.

    1982-10-01

    By order of the Interatom Ltd., Mannesmann-Anlagenbau in Duesseldorf constructed a tube with internal insulation for the HTGR component test facility (KVK I) of Interatom. The test section with a diameter of the pressure tube of approx. 700 mm and a length of approx. 3000 mm contained an axially fixed bellows designed for an internal pressure of 40 bars. An angular movement of the test tube of +- 1.75 deg. was possible. In the region of the pressure resistant bellows a sleeve plated with oxide ceramics and above the fixed seat an axial compensator was integrated in the gas duct which had an internal diameter of 250 mm. In the depressurization test facility of the IRB of the KFA the test section was tested in Helium at pressures up to 35 bars and temperatures between 650 and 1000 0 C. At each temperature level of approx. 650, 800, and 950 0 C the test tube was bent 200 times. Six depressurization experiments were carried out. The results endorse the design data. The depressurization had no influence on the quality of the insulation. The sleeve plated with oxide ceramics and the fixed seat were the weak components. They will have to be redesigned. (orig.) [de

  15. Progress in modeling asphaltene precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Yarranton, H.W.; Satyro, M.A. [Department of Chemical and Petroleum Engineering, University of Calgary (Canada); Taylor, S.D. [DBR Technology Center, Schlumberger (Canada)

    2011-07-01

    In the oil industry, asphaltene precipitation may happen when heavy oils are in contact with a solvent, crude oils are blended or when light oils containing asphaltenes are depressurized. Asphaltene precipitation has proven challenging to predict and the aim of this paper is to evaluate 2 different approaches for asphaltene precipitation modeling: regular solution and equation of state. Two case were studied: an Athabasca bitumen diluted with n-alkane and a depressurized Gulf of Mexico crude oil and both models were applied to each case. Results showed that both thermodynamic models are, to a limited extend, suitable for asphaltene precipitation prediction but they do not offer a correct prediction at low asphaltene concentrations and the equation of state cannot predict asphaltene precipitation from depressurized crude oils. This study showed the limits of current models in predicting precipitation of asphaltene and provided a trick to overcome these deficiencies; further work should be undertaken to develop a consistent approach.

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

    NARCIS (Netherlands)

    G. Liebrechts-Akkerman (Germaine); J.V.M.G. Bovée (Judith); 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

  17. Management of sudden sensorineural hearing loss.

    Science.gov (United States)

    Metrailer, Aaron M; Babu, Seilesh C

    2016-10-01

    Sudden sensorineural hearing loss (SNHL) is an otologic emergency and should be managed quickly and effectively. This review focuses on the management of sudden SNHL, primarily idiopathic sudden SNHL as it is the most common cause. Management options include observation, oral steroids, intratympanic steroids, or combined oral/intratympanic steroids. One-third to two-thirds of patients will achieve spontaneous recovery, most likely within the first 2 weeks. Despite the lack of randomized controlled trials on steroid therapy efficacy, all patients should be offered steroid treatment given low risk and possible significant benefits. All patients should undergo MRI with gadolinium to rule out retrocochlear disorder. Bilateral sudden hearing loss should alert the clinician to possible systemic disease. Sudden hearing loss is an otologic emergency. Appropriate counseling of patients is necessary to allow physician and patient to make a joint, educated decision. It is paramount to rule out retrocochlear disorder and to follow patients closely for improvement or need for future auditory rehabilitation.

  18. Bilateral sudden sensorineural hearing loss: review.

    Science.gov (United States)

    Sara, S A; Teh, B M; Friedland, P

    2014-01-01

    Unilateral and bilateral sudden sensorineural hearing loss represent different disease entities. The unilateral condition is more common and predominantly idiopathic, and up to 65 per cent of patients spontaneously recover hearing. Conversely, the bilateral condition is rare, mostly associated with serious systemic conditions, and has a higher prevalence of morbidity and mortality. A literature search using the PubMed database was conducted using the MeSH terms 'sudden', 'bilateral' and 'sensorineural hearing loss'. One hundred and three reported cases of bilateral sudden sensorineural hearing loss were identified. The condition is most often associated with toxic, autoimmune, neoplastic and vascular conditions. A younger age of onset, with a bimodal age distribution, was seen for bilateral sudden sensorineural hearing loss, compared with the unilateral condition. Patients with the bilateral condition had more profound hearing loss, with poorer recovery and a 35 per cent mortality rate. Vestibular symptoms were also less common than in the unilateral condition. The presentation of bilateral sudden onset sensorineural hearing loss is a medical emergency requiring thorough and urgent investigation to exclude life-threatening and reversible conditions.

  19. 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

  20. Sudden death in water: Diagnostic challenges

    Directory of Open Access Journals (Sweden)

    Elvira Ventura Spagnolo

    2016-03-01

    Full Text Available The authors report a case of sudden death in a breath-holding diver and highlight the forensic diagnostic difficulties in opining the cause of sudden death in water. The autopsy showed increased thickness of the left ventricular wall with a distinct pattern of concentric hypertrophy, evident particularly in the subaortic interventricular septum. Histological examination revealed diffuse interstitial fibrosis and associated findings of multifocal myocyte disarray especially evident in the subaortic interventricular septum. The analysis and discussion of this case made it possible to attribute sudden death to a lethal arrhythmia following myocyte disarray and hypoxia caused by breath-holding, the triggering factor of apnea. This case demonstrates the importance of a thorough forensic investigation, particularly in histological terms, in subjects found dead in water, in order to ascertain the real cause of death, which may not be always ascribable to drowning.

  1. Classification of sudden and arrhythmic death

    DEFF Research Database (Denmark)

    Torp-Pedersen, C; Køber, L; Elming, H

    1997-01-01

    Since all death is (eventually) sudden and associated with cardiac arrhythmias, the concept of sudden death is only meaningful if it is unexpected, while arrhythmic death is only meaningful if life could have continued had the arrhythmia been prevented or treated. Current classifications of death...... as being arrhythmic or sudden are all biased by the difficulty of having to decide on the degree of unexpectedness or the likelihood that life could continue without the arrhythmia. The uncertainties are enlarged by the fact that critical data (such as knowledge of arrhythmias at the time of death...... or autopsy) are available in only a few percent of cases. A main problem in using classifications is the lack of validation data. This situation has, with the MADIT trial, changed in the case of the Thaler and Hinkle classification of arrhythmic death. The MADIT trial demonstrated that arrhythmic death...

  2. Sudden unexpected death in infancy in Denmark

    DEFF Research Database (Denmark)

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

    2011-01-01

    of the ICD-10 code for SIDS (R95) in the Danish Cause of Death registry. Design. A retrospective analysis of all infant deaths (reports were read. Results. We identified 192 SUDI cases (10% of total deaths, 0.42 per 1000 births......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......) 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...

  3. Sudden death in Lesch-Nyhan disease

    Science.gov (United States)

    Neychev, Vladimir Kostadinov; Jinnah, H A

    2012-01-01

    To increase awareness of sudden and unexpected death in Lesch-Nyhan disease (LND) and to explore its potential causes, we report the anteceding clinical features and laboratory evaluations of five males with LND who ultimately experienced sudden and unexpected death, along with three additional males who suffered serious respiratory events during life. The ages of patients ranged from 2 to 45 years. The cause of sudden death in LND appears to have a respiratory rather than a cardiogenic basis. All cases cannot be linked readily with a single respiratory process. Instead, different respiratory processes appear to operate in different cases. These may include aspiration, laryngospasm, central apnea, cyanotic breath-holding spells, and high cervical spine damage. Better recognition of these processes will help to guide appropriate workup and management that could include chest imaging, endoscopy of the airways, polysomnography, electroencephalogram, and brain and/or spine imaging. PMID:17044962

  4. 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

  5. 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

  6. Sudden ionospheric disturbances in solar cycle 24

    Science.gov (United States)

    Bothmer, Volker; Bernert, Barbara

    2014-05-01

    Sudden ionospheric disturbances in solar cycle 24 Within the framework of the UN International Space Weather Initiative, and building upon the achievements of the International Heliophysical Year, the German project SIMONE (Sun Ionosphere MOnitoring NEtwork) operates several SID monitors provided by the University of Stanford. Here we present an overview of sudden ionospheric disturbances recorded since 2006 at the high school Gymnasium Walsrode until to date. The continous measurements allow a detailed comparison of locally measured SIDs with the general trend of solar activity during the current solar maximum. We further show that the measurements reveal specific information on the variable response of the dayside ionosphere to solar flares.

  7. Wave vector modification of the infinite order sudden approximation

    Science.gov (United States)

    Sachs, Judith Grobe; Bowman, Joel M.

    1980-10-01

    A simple method is proposed to modify the infinite order sudden approximation (IOS) in order to extend its region of quantitative validity. The method involves modifying the phase of the IOS scattering matrix to include a part calculated at the outgoing relative kinetic energy as well as a part calculated at the incoming kinetic energy. An immediate advantage of this modification is that the resulting S matrix is symmetric. We also present a closely related method in which the relative kinetic energies used in the calculation of the phase are determined from quasiclassical trajectory calculations. A set of trajectories is run with the initial state being the incoming state, and another set is run with the initial state being the outgoing state, and the average final relative kinetic energy of each set is obtained. One part of the S-operator phase is then calculated at each of these kinetic energies. We apply these methods to vibrationally inelastic collinear collisions of an atom and a harmonic oscillator, and calculate transition probabilities Pn1→nf for three model systems. For systems which are sudden, or nearly so, the agreement with exact quantum close-coupling calculations is substantially improved over standard IOS ones when Δn=‖nf-ni‖ is large, and the corresponding transition probability is small, i.e., less than 0.1. However, the modifications we propose will not improve the accuracy of the IOS transition probabilities for any collisional system unless the standard form of IOS already gives at least qualitative agreement with exact quantal calculations. We also suggest comparisons between some classical quantities and sudden predictions which should help in determining the validity of the sudden approximation. This is useful when exact quantal data is not available for comparison.

  8. 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

  9. 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.

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

    African Journals Online (AJOL)

    product of a gradual recognition and human decision, but an event of a decisive regen- eration, resulting in true and .... Therefore, in a word, I interpret repentance as regeneration, whose sole end is to restore in us the .... by the Word.26 God, by a sudden conversion, subdued and brought his mind to a teachable frame.

  11. 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...

  12. 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.

  13. 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...

  14. 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...

  15. Heart Attack or Sudden Cardiac Arrest: How Are They Different?

    Science.gov (United States)

    ... Attack or Sudden Cardiac Arrest: How Are They Different? Updated:Mar 15,2018 People often use these ... The heart attack symptoms in women can be different than men. What is cardiac arrest? Sudden cardiac ...

  16. 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.

  17. Evolution of IPv6 Internet topology with unusual sudden changes

    International Nuclear Information System (INIS)

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

    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

  18. 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.

  19. 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.

  20. Sudden viscous dissipation in compressing plasma turbulence

    Science.gov (United States)

    Davidovits, Seth; Fisch, Nathaniel

    2015-11-01

    Compression of a turbulent plasma or fluid can cause amplification of the turbulent kinetic energy, if the compression is fast compared to the turnover and viscous dissipation times of the turbulent eddies. The consideration of compressing turbulent flows in inviscid fluids has been motivated by the suggestion that amplification of turbulent kinetic energy occurred on experiments at the Weizmann Institute of Science Z-Pinch. We demonstrate a sudden viscous dissipation mechanism whereby this amplified turbulent kinetic energy is rapidly converted into thermal energy, which further increases the temperature, feeding back to further enhance the dissipation. Application of this mechanism in compression experiments may be advantageous, if the plasma can be kept comparatively cold during much of the compression, reducing radiation and conduction losses, until the plasma suddenly becomes hot. This work was supported by DOE through contract 67350-9960 (Prime # DOE DE-NA0001836) and by the DTRA.

  1. Prognostic factors in sudden hearing loss

    OpenAIRE

    Enache, R; Sarafoleanu, I

    2008-01-01

    Sudden hearing loss is a sensorineural hypoacusis, unilateral in most of the cases, with an incidence peak in young adult. This article is the result of a four years retrospective study, in which we have tried to see how age, severity of hearing loss, presence or absence of vertigo, the timing of treatment initiation can influence the hearing recovery. 47 patients were included in this inpatient study. They were investigated (clinical, lab and imaging studies) and the treatment protocol inclu...

  2. Diagnostics and therapy of sudden hearing loss.

    Science.gov (United States)

    Plontke, Stefan K

    2017-01-01

    This article reviews recent aspects of diagnostics, differential diagnostics, and evidence in systemic and local therapy of idiopathic sudden sensorineural hearing loss (ISSHL). Since a number of disorders can be accompanied by sudden hearing loss, a meaningful and targeted diagnostic strategy is of utmost importance. An important differential diagnosis of sudden hearing loss are intralabyrinthine schwannomas (ILS). The incidence of ILS is probably significantly underestimated. This may be due to the lack of awareness or lack of explicit search for an intralabyrinthine tumor on MRI or an inappropriate MRI technique for the evaluation of sudden hearing loss ("head MRI" instead of "temporal bone MRI" with too high slice thicknesses). Therefore, the request to the radiologist should specifically include the question for (or exclusion of) an ILS. With special MRI techniques, it is possibly today to visualize an endolymphatic hydrops. The evidence in the therapy of ISSHL is - with respect to the quality and not quantity of studies - unsatisfying. The value of systemically (low dose) or intratympanically applied corticosteroids in the primary treatment of ISSHL is still unclear. In order to investigate the efficacy and safety of high dose corticosteroids as primary therapy for ISSHL, a national, multicenter, three-armed, randomized, triple-blind controlled clinical trial is currently performed in Germany (http://hodokort-studie.hno.org/). After insufficient recovery of the threshold with systemic therapy of ISSHL, intratympanic corticosteroid therapy appears to be associated with a significantly higher chance of an improved hearing threshold than no therapy or placebo. Both, hearing gain and final hearing threshold, however, appear to be independent from the onset of secondary therapy. Based on currently available data from clinical studies, no recommendation can be made with respect to the type of corticosteroid and specifics of the intratympanic application protocol.

  3. Imaging spectrum of sudden athlete cardiac death

    Energy Technology Data Exchange (ETDEWEB)

    Arrigan, M.T., E-mail: martinarrigan@gmail.co [Department of Radiology, Adelaide and Meath Hospital incorporating the National Children' s Hospital, Dublin (Ireland); Killeen, R.P. [Department of Radiology, Adelaide and Meath Hospital incorporating the National Children' s Hospital, Dublin (Ireland); Dodd, J.D. [Department of Radiology, St Vincent' s University Hospital, Dublin (Ireland); Torreggiani, W.C. [Department of Radiology, Adelaide and Meath Hospital incorporating the National Children' s Hospital, Dublin (Ireland)

    2011-03-15

    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.

  4. Imaging spectrum of sudden athlete cardiac death

    International Nuclear Information System (INIS)

    Arrigan, M.T.; Killeen, R.P.; Dodd, J.D.; Torreggiani, W.C.

    2011-01-01

    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.

  5. 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.

  6. Suffocation, recurrent apnea, and sudden infant death.

    Science.gov (United States)

    Meadow, R

    1990-09-01

    We reviewed the cases of 27 young children from 27 different families who were suffocated by their mothers. The certainty, or near certainty, of suffocation was based on reliable observation or recording of the suffocation, maternal confession, or successful prosecution in a criminal court. Eighteen of the children are alive, although one has severe brain damage; nine are dead. Twenty-four were reported to have had previous episodes of apnea, cyanosis, or seizure, and 11 had had 10 or more such episodes that were either invented or caused by the mother. Repetitive suffocation usually began between the ages of 1 and 3 months and continued until it was discovered, or the child died, 6 to 12 months later. The 27 children had 15 live elder siblings and 18 who had died suddenly and unexpectedly in early life; 13 of the dead siblings had had recurrent apnea, cyanosis, or seizures, and, although most of them at the time of death were certified as having sudden infant death syndrome, it is probable that some were suffocated. Repetitive suffocation has a characteristic clinical presentation that should allow identification before brain damage or death occurs. The characteristics should also allow the cause of death of some cases of sudden infant death to be established more accurately.

  7. 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.

  8. 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.

  9. Experimental study on secondary depressurization action for PWR vessel bottom small break LOCA with HPI failure and gas inflow (ROSA-V/LSTF test SB-PV-03)

    International Nuclear Information System (INIS)

    Suzuki, Mitsuhiro; Takeda, Takeshi; Asaka, Hideaki; Nakamura, Hideo

    2005-06-01

    A small break loss-of-coolant accident (SBLOCA) experiment was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study effects of accident management (AM) measures on core cooling, which is important in case of high pressure injection (HPI) system failure during an SBLOCA at a pressurized water reactor (PWR). The LSTF is a full-height and 1/48 volume-scaled facility simulating 4-loop Westinghouse-type PWR (3423 MWt). The experiment, SB-PV-03, simulated a PWR vessel bottom SBLOCA with a rupture of ten instrument-tubes which is equivalent to 0.2% cold leg break. Total HPI failure, non-condensable gas inflow from accumulator injection system (AIS) and operator AM actions on steam generator (SG) secondary depressurization at a rate of -55 K/h and auxiliary feedwater (AFW) supply for 30 minutes were assumed as experiment conditions. It is clarified that the AM actions are effective on primary system depressurization until the end of AIS injection at 1.6 MPa, but thereafter become less effective due to inflow of the non-condensable gas, resulting in delay of low pressure injection (LPI) actuation and whole core heatup under continuous water discharge through the bottom break. The report describes these thermohydraulic phenomena related with transient primary coolant mass and AM actions in addition to estimation of non-condensable gas behavior which affected primary-to-secondary heat transfer. (author)

  10. 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

  11. Sudden unexpected death associated with lymphocytic thyroiditis

    DEFF Research Database (Denmark)

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

    2007-01-01

    , 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...... 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...... advocated in cases of sudden unexpected death in order to diagnose thyroid disease, in particular silent (painless) thyroiditis....

  12. The Sudden Madness of Friedrich Nietzsche

    OpenAIRE

    McQueen, David; McMurtrie, W.

    2017-01-01

    A drama investigating the life of the German philosopher Friedrich Nietzsche as told through a series of lectures and demonstrations by Dr. Otto Binswanger at an Institute for the Care and Cure of the Insane in Jena, Germany in 1889. Dr. Binswanger is puzzled by aspects of Nietzsche’s clinical condition. He probes various theories as to the cause of his sudden madness with the patient in front of a group of students. Through this probing and the fragmented memories of Nietzsche we piece toget...

  13. Otolaryngological aspects of sudden infant death syndrome.

    Science.gov (United States)

    Marom, Tal; Cinamon, Udi; Castellanos, Paul F; Cohen, Marta C

    2012-03-01

    Sudden infant death syndrome (SIDS) is characterized by the sudden death of an apparently otherwise healthy infant, typically during sleep, and with no obvious case after a thorough post-mortem and scene death examination. To address the problem from the otolaryngologist's perspective, describe relevant pathologies, discuss controversies and suggest preventive measures in high-risk populations. A MEDLINE search and hand search were conducted to identify reports published between 1969 and 2011 in the English language on the pathophysiology of SIDS related to the head and neck organs. Search terms included SIDS (MeSH term), SIDS and pathophysiology (text words), and SIDS and autopsy (text words). A growing number of reports suggested head and neck organs involvement in SIDS autopsies. Laryngeal, oropharyngeal, maxillofacial, otologic, cervical vascular abnormalities and infectious etiologies, were recognized and discussed. Otolaryngologists should be aware of relevant pathologies, as some are treatable, if identified early enough in infancy. A proactive risk-management approach is warranted in infants presenting with certain abnormalities reviewed here. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Ion Channel Disorders and Sudden Cardiac Death

    Directory of Open Access Journals (Sweden)

    Anna Garcia-Elias

    2018-02-01

    Full Text Available Long QT syndrome, short QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia are inherited primary electrical disorders that predispose to sudden cardiac death in the absence of structural heart disease. Also known as cardiac channelopathies, primary electrical disorders respond to mutations in genes encoding cardiac ion channels and/or their regulatory proteins, which result in modifications in the cardiac action potential or in the intracellular calcium handling that lead to electrical instability and life-threatening ventricular arrhythmias. These disorders may have low penetrance and expressivity, making clinical diagnosis often challenging. However, because sudden cardiac death might be the first presenting symptom of the disease, early diagnosis becomes essential. Genetic testing might be helpful in this regard, providing a definite diagnosis in some patients. Yet important limitations still exist, with a significant proportion of patients remaining with no causative mutation identifiable after genetic testing. This review aims to provide the latest knowledge on the genetic basis of cardiac channelopathies and discuss the role of the affected proteins in the pathophysiology of each one of these diseases.

  15. 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.

  16. Initial conditions and entanglement sudden death

    International Nuclear Information System (INIS)

    Qian, Xiao-Feng; Eberly, J.H.

    2012-01-01

    We report results bearing on the behavior of non-local decoherence and its potential for being managed or even controlled. The decoherence process known as entanglement sudden death (ESD) can drive prepared entanglement to zero at the same time that local coherences and fidelity remain non-zero. For a generic ESD-susceptible Bell superposition state, we provide rules restricting the occurrence and timing of ESD, amounting to management tools over a continuous variation of initial conditions. These depend on only three parameters: initial purity, entanglement and excitation. Knowledge or control of initial phases is not needed. -- Highlights: ► We study the possibility of managing disentanglement through initial conditions. ► The initial parameters are the amount of entanglement, excitation, and purity. ► Entanglement sudden death (ESD) free and ESD susceptible phases are identified. ► ESD onset time is also presented in the ESD susceptible phase. ► Our results may guide experiments to prepare ESD free or delayed ESD states.

  17. 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....... A cardiac disease was known prior to death in 18% of all sudden unexpected death cases. In two-thirds of all sudden unexpected death cases no previous medical history was registered. Causes of death in autopsied cases were cardiac or unknown in 70%. Unexplained deaths, presumed to be a primary cardiac......, and syncope. In total, 61% of SCDc were not known with any prior disease; 23% were known with congenital or other heart disease prior to death. In total, 43 (49%) of all sudden unexpected deaths died of a potential inherited cardiac disease. The incidence rate of sudden unexpected death was 1.5 per 100 000...

  18. Residual entanglement and sudden death: A direct connection

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, J.G.G. de, E-mail: zgeraldo@ufrb.edu.br [Centro de Formação de Professores, Universidade Federal do Recôncavo da Bahia, 45.300-000, Amargosa, BA (Brazil); Departamento de Física, CP 702, Universidade Federal de Minas Gerais, 30123-970, Belo Horizonte, MG (Brazil); Peixoto de Faria, J.G., E-mail: jgpfaria@des.cefetmg.br [Departamento de Física e Matemática, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000, Belo Horizonte, MG (Brazil); Nemes, M.C., E-mail: carolina@fisica.ufmg.br [Departamento de Física, CP 702, Universidade Federal de Minas Gerais, 30123-970, Belo Horizonte, MG (Brazil)

    2011-11-21

    We explore the results of [V. Coffman, et al., Phys. Rev. A 61 (2000) 052306] derived for general tripartite states in a dynamical context. We study a class of physically motivated tripartite systems. We show that whenever entanglement sudden death occurs in one of the partitions residual entanglement will appear. For fourpartite systems however, the appearance of residual entanglement is not conditioned by sudden death of entanglement. We can only say that if sudden death of entanglement occurs in some partition there will certainly be residual entanglement. -- Highlights: ► For tripartite systems we show there exists residual entanglement if sudden death occurs. ► For fourpartite systems, the residual entanglement is not conditioned by sudden death. ► If sudden death of entanglement occurs there will certainly be residual entanglement.

  19. Heavy ion interaction in the sudden and adiabatic approximation

    International Nuclear Information System (INIS)

    Ali, S.El-Sayed

    1997-01-01

    This thesis is concerned with the calculation of the real part of the optical potential and the fusion cross-section of the 1 2C+ 1 2C system in the framework of the energy density formalism. The energy density functional of Skyrme interaction is used in the calculation. The densities of the combined system 1 2C+ 1 2C and of the separated nuclei are determined by the two center shell model (TCSM) in the sudden and adiabatic approximations. The spin density part of the interaction potential and its effects on the nuclear potential and the fusion cross- section is studied. Chapter(1) is an introduction. Chapter (2) gives the derivation of the model densities. The ground state of the two nuclei is taken as slater determinant built from a non-orthogonal basis of two harmonic oscillator potentials centered at two different points separated by a distance R. In this framework the matter, kinetic energy, momentum densities and the spin density are calculated. Chapter (3) presents the calculation of the real part of the optical potential of the system 1 2C+ 1 2C, in the sudden and adiabatic approximations. The calculations are based on the TCSM proposed in chapter (2), for different values of the relative energy between the ions where the Skyrme force parameters SIII and skm are used. We assumed a simple adiabatic model, where the nucleons rearrangement at each separation can be simulated in the densities by considering a variational oscillator parameter b, determined by minimizing the energy with respect to it. The spin density part of the interaction potential and its effect on the nuclear potential is examined. In chapter (4), the fusion cross-section of the system 1 2C+ 1 2C is calculated using the interaction potential calculated in chapter (3). We studied the effect of the spin density part of the interaction potential on the fusion cross-section, in the sudden and adiabatic approximations. The results are compared with experiments. 1 tabs.,4-4 figs.,43 refs

  20. 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.

  1. 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.

  2. Sudden gains versus gradual gains in a psychotherapy training clinic.

    Science.gov (United States)

    Greenfield, Michael F; Gunthert, Kathleen C; Haaga, David A F

    2011-01-01

    Sudden gains are abrupt and substantial improvements in symptoms. This study used the Outcome Questionnaire-45 (OQ-45; Lambert et al., 1996) to characterize sudden gains occurring in a cognitive-behavioral therapy training clinic. Also, gradual gainers were identified and used as a comparison group. Sudden gains were identified in 23% of patients and in 29% of those who entered treatment in the clinical range on the OQ, within the range of prevalence established by previous sudden gain studies in the context of randomized controlled trials (RCT's). As in earlier research, sudden gains tended to occur early in therapy. However, sudden gains were more likely to be reversed than in RCT's. Gradual gains occurred for 54% of nonsudden gainers; they were of similar magnitude to sudden gains but occurred later in therapy. Sudden gainers showed significantly better outcomes at the end of treatment than did gradual gainers. Sudden gains have clear prognostic significance, but more research is needed to determine why they may be more transient in naturalistic studies or studies involving less experienced therapists than they are in RCT's. © 2010 Wiley Periodicals, Inc.

  3. 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

  4. Prognostic factors in sudden hearing loss

    Science.gov (United States)

    Enache, R

    2008-01-01

    Sudden hearing loss is a sensorineural hypoacusis, unilateral in most of the cases, with an incidence peak in young adult. This article is the result of a four years retrospective study, in which we have tried to see how age, severity of hearing loss, presence or absence of vertigo, the timing of treatment initiation can influence the hearing recovery. 47 patients were included in this inpatient study. They were investigated (clinical, lab and imaging studies) and the treatment protocol included vasodilators, anti–inflammatory agents, vitamins, plasma expander. In conclusion, a good prognosis in the hearing recovery was associated with absence of vertigo, early treatment (the first 7 days), and hearing loss less than 50dB. Age had no influence upon the recovery process. PMID:20108511

  5. Symptoms Before Sudden Arrhythmic Death Syndrome

    DEFF Research Database (Denmark)

    Glinge, Charlotte; Jabbari, Reza; Risgaard, Bjarke

    2015-01-01

    of SADS. METHODS AND RESULTS: We have previously identified all of the autopsied sudden cardiac deaths (SCD; n = 314) in Danes aged 1-35 years between 2000 and 2006. After comprehensive pathological and toxicological investigation did not reveal a cause of SCD, 136 of the patients were identified as SADS......%), palpitations (n = 2, 1%), presyncope/syncope (n = 23, 17%), and aborted SCD (n = 2, 1%). In addition, seizures (n = 25, 18%) were prevalent. In 61 (45%) SADS cases, no previous medical history were recorded. CONCLUSION: In this unselected, nationwide study of 136 young SADS patients, 35% had experienced...... cardiac symptoms before death, most commonly presyncope/syncope, but only one out of five had contacted a healthcare provider with cardiac symptoms....

  6. Sudden infant death syndrome and weather temperature.

    Science.gov (United States)

    Mitchell, E A; Stewart, A W; Cowan, S F

    1992-01-01

    The relationship between the days on which sudden infant death syndrome (SIDS) occurred and the daily minimum temperature was examined in Auckland (1979-1984) and Christchurch (1979-1987). There was a marked winter excess of deaths in both regions. There was a significant negative correlation between the monthly mean minimum temperature and SIDS rate for both regions (r = -0.43, n = 347, P less than 0.0001). The monthly mean minimum temperature describes SIDS mortality equally as well as the three variables of daily minimum temperature, season and geographical location. There was a significant association of SIDS with minimum temperature 4 and 5 days prior to the death after adjusting for the effect of monthly mean minimum temperature. The days preceding death were on average colder than the other days, but the effect was small, especially when compared with the magnitude of the temperature differences between consecutive months.

  7. 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.

  8. Entanglement dynamics following a sudden quench: An exact solution

    Science.gov (United States)

    Ghosh, Supriyo; Gupta, Kumar S.; Srivastava, Shashi C. L.

    2017-12-01

    We present an exact and fully analytical treatment of the entanglement dynamics for an isolated system of N coupled oscillators following a sudden quench of the system parameters. The system is analyzed using the solutions of the time-dependent Schrodinger's equation, which are obtained by solving the corresponding nonlinear Ermakov equations. The entanglement entropies exhibit a multi-oscillatory behaviour, where the number of dynamically generated time scales increases with N. The harmonic chains exhibit entanglement revival and for larger values of N (> 10), we find near-critical logarithmic scaling for the entanglement entropy, which is modulated by a time-dependent factor. The N = 2 case is equivalent to the two-site Bose-Hubbard model in the tunneling regime, which is amenable to empirical realization in cold-atom systems.

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  10. Sudden Infant Death Syndrome in Mice with an Inherited Mutation in RyR2

    Science.gov (United States)

    Mathur, Nitin; Sood, Subeena; Wang, Sufen; van Oort, Ralph J.; Sarma, Satyam; Li, Na; Skapura, Darlene G.; Bayle, J. Henri; Valderrábano, Miguel; Wehrens, Xander H.T.

    2009-01-01

    Background Mutations in the cardiac ryanodine receptor gene (RYR2) have been recently identified in victims of sudden infant death syndrome (SIDS). The aim of this study was to determine whether a gain-of-function mutation in RYR2 increases the propensity to cardiac arrhythmias and sudden death in young mice. Methods and Results Incidence of sudden death was monitored prospectively in heterozygous knock-in mice with mutation R176Q in Ryr2 (R176Q/+). Young R176Q/+ mice exhibited a higher incidence of sudden death compared with wild-type (WT) littermates. Optical mapping of membrane potentials and calcium levels in 1-7 day-old R176Q/+ and WT mice revealed an increased incidence of ventricular ectopy and spontaneous calcium releases in neonatal R176Q/+ mice. Surface ECGs in 3-10 day-old mice showed that R176Q/+ mice developed more ventricular arrhythmias following provocation with epinephrine and caffeine. Intracardiac pacing studies in 12-18 day-old mice revealed the presence of an arrhythmogenic substrate in R176Q/+ compared with WT mice. RT-PCR and Western blotting showed that expression levels of other calcium handling proteins were unaltered suggesting that calcium leak through mutant RyR2 underlies arrhythmogenesis and sudden death in young R176Q/+ mice. Conclusions Our findings demonstrate that a gain-of-function mutation in RyR2 confers an increased risk of cardiac arrhythmias and sudden death in young mice, and that young R176Q/+ mice may be used as a model for elucidating the complex interplay between genetic and environmental risk factors associated with SIDS. PMID:20009080

  11. Sudden and unexpected childhood deaths investigated at the ...

    African Journals Online (AJOL)

    Background. Sudden and unexpected death is well known to occur in infants, and although sudden deaths are less frequent after the first birthday, they still account for a significant proportion of childhood deaths. In 2009, 1.9% of the total deaths in the USA were childhood deaths. In South Africa (SA) this proportion was ...

  12. Sudden stops and current account reversals: the euro area experience

    Directory of Open Access Journals (Sweden)

    Svrtinov Vesna Georgieva

    2015-12-01

    Full Text Available The paper analyzes the impact of massive capital flows and possible sudden stops on current account reversals. The aim of this paper is to consider the relationship between sudden stops and current account reversals in the eurozone and to explain the possibility of a balance-of-payment crisis within a monetary union.

  13. A honey bee can threat ear: Sudden sensorineural hearing loss.

    Science.gov (United States)

    Düzenli, Ufuk; Bozan, Nazım; Ayral, Abdurrahman; Yalınkılıç, Abdülaziz; Kıroğlu, Ahmet Faruk

    2017-11-01

    Sudden sensorineural hearing loss is an otologic emergency. Many etiological factors can lead to this pathology. Honey bee (Apis mellifera) sting may lead to local and systemic reactions due to sensitization of the patient. In this paper we described a sudden sensorineural hearing loss occurred after honey bee sting. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Mobile phone usage does not affect sudden sensorineural hearing loss.

    Science.gov (United States)

    Sagiv, D; Migirov, L; Madgar, O; Nakache, G; Wolf, M; Shapira, Y

    2018-01-01

    Recent studies found that mobile phone users had a significantly greater risk of having elevated thresholds in speech frequencies. This study investigated the correlation between the laterality of sudden sensorineural hearing loss, handedness and the preferred ear for mobile phone use. The study included all patients who presented with sudden sensorineural hearing loss to the Department of Otolaryngology - Head and Neck Surgery in our tertiary referral medical centre between 2014 and 2016. Patients were asked to indicate their dominant hand and preferred ear for mobile phone use. The study comprised 160 patients. No correlation was found between the dominant hand or preferred ear for mobile phone use and the side of sudden sensorineural hearing loss. There was no correlation between the side of the sudden sensorineural hearing loss (preferable or non-preferable for mobile phone use) and audiometric characteristics. No correlation was found between the laterality of ears used for mobile phone and sudden sensorineural hearing loss.

  15. Sudden death after medullary infarction—A case report

    Directory of Open Access Journals (Sweden)

    Yuh-Jen Wang

    2013-10-01

    Full Text Available Sudden death in a stable medullary infarction case frequently induces legal problems. Currently, the etiology of the most reported cases are not known because autopsy is rare. Here, we report one female patient with medullary infarction who experienced a sudden cardiopulmonary arrest during a brain magnetic resonance imaging (MRI study. The blood flow changes on the MRI indicated that her death resulted from the sudden collapse of systemic circulation. Dysautonomia, or sudden respiratory arrest resulting from brainstem dysfunction, was suspected. In this report, we present her cranial MRI findings and discuss the possible pathophysiology after reviewing the relevant literature. We also recommend certain tests for patients with medullary infarction to prevent the risk of sudden unexpected deaths.

  16. Structural imaging biomarkers of sudden unexpected death in epilepsy.

    Science.gov (United States)

    Wandschneider, Britta; Koepp, Matthias; Scott, Catherine; Micallef, Caroline; Balestrini, Simona; Sisodiya, Sanjay M; Thom, Maria; Harper, Ronald M; Sander, Josemir W; Vos, Sjoerd B; Duncan, John S; Lhatoo, Samden; Diehl, Beate

    2015-10-01

    Sudden unexpected death in epilepsy is a major cause of premature death in people with epilepsy. We aimed to assess whether structural changes potentially attributable to sudden death pathogenesis were present on magnetic resonance imaging in people who subsequently died of sudden unexpected death in epilepsy. In a retrospective, voxel-based analysis of T1 volume scans, we compared grey matter volumes in 12 cases of sudden unexpected death in epilepsy (two definite, 10 probable; eight males), acquired 2 years [median, interquartile range (IQR) 2.8] before death [median (IQR) age at scanning 33.5 (22) years], with 34 people at high risk [age 30.5 (12); 19 males], 19 at low risk [age 30 (7.5); 12 males] of sudden death, and 15 healthy controls [age 37 (16); seven males]. At-risk subjects were defined based on risk factors of sudden unexpected death in epilepsy identified in a recent combined risk factor analysis. We identified increased grey matter volume in the right anterior hippocampus/amygdala and parahippocampus in sudden death cases and people at high risk, when compared to those at low risk and controls. Compared to controls, posterior thalamic grey matter volume, an area mediating oxygen regulation, was reduced in cases of sudden unexpected death in epilepsy and subjects at high risk. The extent of reduction correlated with disease duration in all subjects with epilepsy. Increased amygdalo-hippocampal grey matter volume with right-sided changes is consistent with histo-pathological findings reported in sudden infant death syndrome. We speculate that the right-sided predominance reflects asymmetric central influences on autonomic outflow, contributing to cardiac arrhythmia. Pulvinar damage may impair hypoxia regulation. The imaging findings in sudden unexpected death in epilepsy and people at high risk may be useful as a biomarker for risk-stratification in future studies. The Author (2015). Published by Oxford University Press on behalf of the Guarantors of

  17. Sudden Death Following Exercise; a Case Series Study

    Directory of Open Access Journals (Sweden)

    Fares Najari

    2016-04-01

    Full Text Available Introduction: Natural and unexpected death that happens within less than one hour of first symptom occurrence is called sudden death. Cardiovascular diseases are the main known reason of sudden death and more than 75% of sudden deaths in athletes are assigned to it. Here we reported the autopsy results of all cases with sudden death following exercise that were referred to forensic center of Tehran, Iran, from 2009 to 2014. Methods: In this cross sectional study all subjects who were registered to forensic medicine center of Tehran, Iran, from 2009 to 2014, as a case of sudden death following exercise were evaluated. Demographic data and medical history as well as autopsy and toxicology findings were retrospectively gathered using profiles of the deceased. Results were reported using descriptive analysis. Results: 14 cases were registered as sudden death following exercise in forensic medicine profiles during the study period. Exploring the files of the mentioned deceased, revealed five non-compatible cases in this regard. Finally, 9 eligible cases were enrolled (88.9% male. The mean age of the deceased was 28.66 ± 10.86 years (range: 7 – 40. Toxicological tests were available for 7 cases, one of which was positive for tramadol. Sudden death following football was reported most frequently (44.4%. Only 3 (33.3% cases had herald signs such as chest pain, syncope, or loss of consciousness. 1 case (11.11% had a positive history of sudden death in relatives. Conclusion: Although most sudden death victims are asymptomatic until the event, all those who suffer from symptoms such as chest pain, shortness of breath, dizziness, fatigue and irregular heart rate during physical activities, should be screened regarding common probable causes of sudden death.

  18. Febrile seizures prior to sudden cardiac death

    DEFF Research Database (Denmark)

    Stampe, Niels Kjær; Glinge, Charlotte; Jabbari, Reza

    2018-01-01

    Aims: Febrile seizure (FS) is a common disorder affecting 2-5% of children up to 5 years of age. The aim of this study was to determine whether FS in early childhood are over-represented in young adults dying from sudden cardiac death (SCD). Methods and results: We included all deaths (n = 4595......; 3.0%) and also in victims of transport accidents (26/917; 2.8%). The frequency of FS among SCD cases was significantly increased by an odds ratio of 1.96 [95% confidence interval (CI) 1.14-3.36; P = 0.021] compared with the living Danish population and with an odds ratio of 2.08 (95% CI 1.07-4.04; P......) nationwide and through review of all death certificates, we identified 245 SCD in Danes aged 1-30 years in 2000-09. Through the usage of nationwide registries, we identified all persons admitted with first FS among SCD cases (14/245; 5.7%) and in the corresponding living Danish population (71 027/2 369 785...

  19. 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.

  20. 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.

  1. Sudden Unexpected Death in Fetal Life Through Early Childhood.

    Science.gov (United States)

    Goldstein, Richard D; Kinney, Hannah C; Willinger, Marian

    2016-06-01

    In March 2015, the Eunice Kennedy Shriver National Institute of Child Health and Human Development held a workshop entitled "Sudden Unexpected Death in Fetal Life Through Early Childhood: New Opportunities." Its objective was to advance efforts to understand and ultimately prevent sudden deaths in early life, by considering their pathogenesis as a potential continuum with some commonalities in biological origins or pathways. A second objective of this meeting was to highlight current issues surrounding the classification of sudden infant death syndrome (SIDS), and the implications of variations in the use of the term "SIDS" in forensic practice, and pediatric care and research. The proceedings reflected the most current knowledge and understanding of the origins and biology of vulnerability to sudden unexpected death, and its environmental triggers. Participants were encouraged to consider the application of new technologies and "omics" approaches to accelerate research. The major advances in delineating the intrinsic vulnerabilities to sudden death in early life have come from epidemiologic, neural, cardiac, metabolic, genetic, and physiologic research, with some commonalities among cases of unexplained stillbirth, SIDS, and sudden unexplained death in childhood observed. It was emphasized that investigations of sudden unexpected death are inconsistent, varying by jurisdiction, as are the education, certification practices, and experience of death certifiers. In addition, there is no practical consensus on the use of "SIDS" as a determination in cause of death. Major clinical, forensic, and scientific areas are identified for future research. Copyright © 2016 by the American Academy of Pediatrics.

  2. The 'patient journey' of adults with sudden-onset acquired hearing impairment: a pilot study.

    Science.gov (United States)

    Manchaiah, V K C; Stephens, D

    2012-05-01

    A previous study examined the 'patient journey' of adults with gradual-onset acquired hearing impairment. This study examined the same for adults with sudden-onset acquired hearing impairment, and assessed differences. Data were collected from 16 audiologists, using the Ida Institute template, and from four adults with sudden-onset acquired hearing impairment, through semi-structured interviews. Data were analysed using thematic analysis and presented using a process mapping model. A patient journey template for sudden-onset acquired hearing impairment was developed based on the professionals' and patients' perspectives. The main difference between these two groups' perspectives was seen in the self-evaluation phase: some stages within this phase were recognised by the patients but not by the professionals. The main difference between the current and the previous study was the absence of a pre-awareness phase in the journey described by patients with sudden-onset acquired hearing impairment, compared with that described by patients with gradual-onset acquired hearing impairment. Patient journey templates could be useful counselling tools for ear and hearing healthcare specialists. However, such templates should be used only as a baseline; it is important to take a detailed case history to understand each patient's unique experience, including the psychosocial impact of hearing impairment.

  3. Advanced Electrocardiographic Predictors of Sudden Death in Familial Dysautonomia

    Science.gov (United States)

    Solaimanzadeh, I.; Schlegel, T. T.; Greco, E. C.; DePalma, J. L.; Starc, V.; Marthol, H.; Tutaj, M.; Buechner, S.; Axelrod, F. B.; Hilz, M. J.

    2007-01-01

    To identify accurate predictors for the risk of sudden death in patients with familial dysautonomia (FD). Ten-minute resting high-fidelity 12-lead ECGs were obtained from 14 FD patients and 14 age/gender-matched healthy subjects. Multiple conventional and advanced ECG parameters were studied for their ability to predict sudden death in FD over a subsequent 4.5-year period, including multiple indices of linear and non-linear heart rate variability (HRV); QT variability; waveform complexity; high frequency QRS; and derived Frank-lead parameters. Four of the 14 FD patients died suddenly during the follow-up period, usually with concomitant pulmonary disorder. The presence of low vagally-mediated HRV was the ECG finding most predictive of sudden death. Concomitant left ventricular hypertrophy and other ECG abnormalities such as increased QTc and JTc intervals, spatial QRS-T angles, T-wave complexity, and QT variability were also present in FD patients, suggesting that structural heart disease is fairly common in FD. Although excessive or unopposed cardiac vagal (relative to sympathetic) activity has been postulated as a contributor to sudden death in FD, the presence of low vagally-mediated HRV was paradoxically the best predictor of sudden death. However, we suggest that low vagally-mediated HRV be construed not as a direct cause of sudden death in FD, but rather as an effect of concurrent pathological processes, especially hypoxia due to pulmonary disorders and sleep apnea, that themselves increase the risk of sudden death in FD and simultaneously diminish HRV. We speculate that adenosine may play a role in sudden death in FD, possibly independently of vagal activity, and that adenosine inhibitors such as theophylline might therefore be useful as prophylaxis in this disorder.

  4. MR Imaging in Sudden Sensorineural Hearing Loss. Time to Talk.

    Science.gov (United States)

    Conte, G; Di Berardino, F; Sina, C; Zanetti, D; Scola, E; Gavagna, C; Gaini, L; Palumbo, G; Capaccio, P; Triulzi, F

    2017-08-01

    Sudden sensorineural hearing loss is defined as acute hearing loss of the sensorineural type of at least 30 dB over 3 contiguous frequencies that occurs within a 72-hour period. Although many different causative factors have been proposed, sudden sensorineural hearing loss is still considered "idiopathic" in 71%-85% of cases, and treatments are empiric, not based on etiology. MR imaging implemented with a 3D FLAIR sequence has provided new insights into the etiology of sudden sensorineural hearing loss. Herein, we review the current management trends for patients with sudden sensorineural hearing loss, from the initial clinical diagnosis to therapeutic strategies and diagnostic work-up. We focused primarily on MR imaging assessment and discuss the relevance that MR imaging findings might have for patient management, pointing out different perspectives for future clinical research. © 2017 by American Journal of Neuroradiology.

  5. [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.

  6. The epidemiology of sudden oak death in Oregon forests

    Science.gov (United States)

    Ebba K. Peterson

    2011-01-01

    The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus...

  7. A study on timing of rapid depressurization action during PWR vessel bottom break LOCA with HPI failure and AIS-gas inflow (ROSA-V/LSTF test SB-PV-06)

    International Nuclear Information System (INIS)

    Suzuki, Mitsuhiro; Takeda, Takeshi; Asaka, Hideaki; Nakamura, Hideo

    2007-03-01

    A small break loss-of-coolant accident (SBLOCA) experiment (SB-PV-06) was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study the effects of initiation timing of rapid secondary depressurization action on core cooling as one of accident management (AM) measures for a pressurized water reactor (PWR) in case of high pressure injection (HPI) system failure and non-condensable gas inflow from the accumulator injection system (AIS). The break simulated rupture of 10 instrument tubes at the vessel bottom equivalent to 0.2% cold leg break. The rapid depressurization action was initiated after the vessel level below the primary loop nozzle was detected. The results were compared with those of two similar experiments of SB-PV-03 in which the action was initiated after core heat-up, and SB-PV-04 in which the earliest action was initiated by safety injection (SI) signal with 10 minutes delay resulting in adequate core cooling. It is clarified that the vessel level indication for start of the AM action is less effective on core cooling, while steam generator (SG) outlet plenum level indication for earlier AM action can be effective due to larger primary coolant mass as in the SB-PV-04 experiment. The report compares these experimental results to clarify the effects of the initiation timing of rapid secondary depressurization action on core cooling in addition to the precise results of the SB-PV-06 experiment. (author)

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

    OpenAIRE

    Shibata, Dean K.; Johnston, S. Claiborne

    2015-01-01

    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 macroglobulin...

  9. 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.

  10. Liquid entrainment and off-take at the top of the pressurizer in the case of the actuation of safety depressurization system of APR1400

    International Nuclear Information System (INIS)

    Kim, Chang Hyun; No, Hee Cheon

    2003-01-01

    In order to determine the bleed capacity of Safety Depressurization System (SDS) of Advanced Power Reactor 1400 (APR1400) in case of Total Loss of Feed Water (TLOFW), we performed an experimental study of liquid entrainment and liquid off-take from the swelled two-phase mixture surface in a vessel. A total of 208 experimental data on the entrainment and off-take are obtained using a test vessel with the height of 2.0m and the inner diameter of 0.3m having a top break with diameter of 0.05m. Two-phase mixture levels are measured by the ultrasonic sensor within ? .77% with respect to the visual level data. Droplet entrainments are measured and compared with the existing pool entrainment data. The empirical correlation for the onset of off-take is developed in terms of the Froude number (Fr g ) at the break and non-dimensional inception height (h b /d). This correlation shows agreement with the present experimental data within ? 5%. The present off-take quality data is in agreement with Schrock's off-take quality correlation with the r.m.s. error of 15.8%. In the present experiment, droplet entrainment E fg strongly depends upon jg * /h * and is proportional to the 7 th power of jg * /h * in the same way as the off-take data

  11. Prognostic Factors in Sudden Sensorineural Hearing Loss

    Directory of Open Access Journals (Sweden)

    Gamze Atay

    2016-02-01

    Full Text Available Background: Sudden sensorineural hearing loss (SSNHL is still a complex and challenging process which requires clinical evidence regarding its etiology, treatment and prognostic factors. Therefore, determination of prognostic factors might aid in the selection of proper treatment modality. Aims: The aim of this study is to analyze whether there is correlation between SSNHL outcomes and (1 systemic steroid therapy, (2 time gap between onset of symptoms and initiation of therapy and (3 audiological pattern of hearing loss. Study Design: Retrospective chart review. Methods: Patients diagnosed at our clinic with SSNHL between May 2005 and December 2011were reviewed. A detailed history of demographic features, side of hearing loss, previous SSNHL and/or ear surgery, recent upper respiratory tract infection, season of admission, duration of symptoms before admission and the presence of co-morbid diseases was obtained. Radiological and audiological evaluations were recorded and treatment protocol was assessed to determine whether systemic steroids were administered or not. Treatment started ≤5 days was regarded as “early” and >5 days as “delayed”. Initial audiological configurations were grouped as “upward sloping”, “downward sloping”, “flat” and “profound” hearing loss. Significant recovery was defined as thresholds improved to the same level with the unaffected ear or improved ≥30 dB on average. Slight recovery was hearing improvement between 10-30dB on average. Hearing recovery less than 10 dB was accepted as unchanged. Results: Among the 181 patients who met the inclusion criteria, systemic steroid was administered to 122 patients (67.4%, whereas 59 (32.6% patients did not have steroids. It was found that steroid administration did not have any statistically significant effect in either recovered or unchanged hearing groups. Early treatment was achieved in 105 patients (58% and 76 patients (42% had delayed treatment

  12. Risk of sudden sensorineural hearing loss in adults using phosphodiesterase type 5 inhibitors: Population-based cohort study.

    Science.gov (United States)

    Liu, Wei; Antonelli, Patrick J; Dahm, Philipp; Gerhard, Tobias; Delaney, Joseph A C; Segal, Richard; Crystal, Stephen; Winterstein, Almut G

    2018-03-07

    The objective of the study was to determine the risk of sudden sensorineural hearing loss (SNHL) associated with use of phosphodiesterase type 5 (PDE5) inhibitors. We conducted a retrospective cohort study in the MarketScan Commercial Claims and Encounters Database including adult men who initiated a PDE5 inhibitor (n = 377,722) and 1,957,233 nonusers between 1998 and 2007. Periods of drug exposure were assessed on a weekly basis based on pharmacy billing records, assuming use of 1 dose per week (current use). Incident sudden SNHL was defined based on inpatient or outpatient visits with International Classification of Diseases, Ninth Revision, Clinical Modification codes 389.1x, 389.2x, or 388.2 plus ≥2 procedure codes for audiometric hearing testing within ±30 days of sudden SNHL diagnosis. We used age- and propensity score-adjusted Cox proportional hazards model to evaluate the risk of sudden SNHL during periods of current or recent use compared with that of nonuse. We conducted sensitivity analyses by varying the assumed drug utilization frequency and sudden SNHL case definition. We evaluated 1233 sudden SNHL cases, resulting in an incidence of 4.35, 5.58, and 2.38 per 10,000 person-years for current, recent, and nonuse of PDE5 inhibitors, respectively. Compared with nonuse, the adjusted hazard ratio was 1.25 (1.01-1.55) for current use with a risk difference of 1.97 (1.12-2.82) per 10,000 person-years. For recent use, the adjusted hazard ratio was 1.60 (1.33-1.94) and risk difference was 3.19 (2.24-4.14). Estimates were consistent across the sensitivity analyses. Use of PDE5 inhibitors is associated with a small but significantly increased risk of sudden SNHL. Copyright © 2018 John Wiley & Sons, Ltd.

  13. The initial phase of sudden releases of superheated liquid

    International Nuclear Information System (INIS)

    Schmidli, J.; Yadigaroglu, G.

    1994-01-01

    Series of experiments were conducted with refrigerants-114, -12, propane and butane to investigate the initial phase of sudden releases of superheated liquids due to the catastrophic failure of the vessel containing them. The experiments were initiated by shattering spherical flasks of 100 to 2000 ml containing the liquefied, pressurized gases. The variable parameters were the initial superheat, the filling level, the height of the flask above ground, and the relative humidity of the surrounding air. It was found that the initial flashing process is not determined by homogeneous nucleation, but rather by surface instabilities which lead to an evaporation wave traveling from the initial surface towards the center of the released mass. Cloud shape and expansion velocity could be determined from high speed recordings covering the initial stage of the release during which gravity has no influence. When the internal energy was sufficient, it was observed that the expanding droplet/vapor cloud initially propagated spherically with a constant expansion velocity, until Rayleigh-Taylor type instabilities appeared at its surface. Information about the pool which can be formed on the ground, the pressure decay within the flask, the droplet size, and the cloud temperature was collected. The experimental findings for the expansion velocity, as well as for the pool fraction, were the base for a nondimensional analysis leading to correlations which describe the initial phase of such releases and can be used to define the ''source term'' for turbulent dispersion models. (author) 5 figs., 1 tab., 15 refs

  14. 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.

  15. Sudden Cardiac Arrest during Participation in Competitive Sports.

    Science.gov (United States)

    Landry, Cameron H; Allan, Katherine S; Connelly, Kim A; Cunningham, Kris; Morrison, Laurie J; Dorian, Paul

    2017-11-16

    The incidence of sudden cardiac arrest during participation in sports activities remains unknown. Preparticipation screening programs aimed at preventing sudden cardiac arrest during sports activities are thought to be able to identify at-risk athletes; however, the efficacy of these programs remains controversial. We sought to identify all sudden cardiac arrests that occurred during participation in sports activities within a specific region of Canada and to determine their causes. In this retrospective study, we used the Rescu Epistry cardiac arrest database (which contains records of every cardiac arrest attended by paramedics in the network region) to identify all out-of-hospital cardiac arrests that occurred from 2009 through 2014 in persons 12 to 45 years of age during participation in a sport. Cases were adjudicated as sudden cardiac arrest (i.e., having a cardiac cause) or as an event resulting from a noncardiac cause, on the basis of records from multiple sources, including ambulance call reports, autopsy reports, in-hospital data, and records of direct interviews with patients or family members. Over the course of 18.5 million person-years of observation, 74 sudden cardiac arrests occurred during participation in a sport; of these, 16 occurred during competitive sports and 58 occurred during noncompetitive sports. The incidence of sudden cardiac arrest during competitive sports was 0.76 cases per 100,000 athlete-years, with 43.8% of the athletes surviving until they were discharged from the hospital. Among the competitive athletes, two deaths were attributed to hypertrophic cardiomyopathy and none to arrhythmogenic right ventricular cardiomyopathy. Three cases of sudden cardiac arrest that occurred during participation in competitive sports were determined to have been potentially identifiable if the athletes had undergone preparticipation screening. In our study involving persons who had out-of-hospital cardiac arrest, the incidence of sudden cardiac

  16. 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.

  17. 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.

  18. Numerical simulation of wave interactions during sudden stratospheric warming

    Science.gov (United States)

    Gavrilov, N. M.; Koval, A. V.; Pogoreltsev, A. I.; Savenkova, E. N.

    2017-11-01

    Parameterizations of normal atmospheric modes (NAMs) and orographic gravity waves (OGWs) are implemented into the mechanistic general circulation model of the middle and upper atmosphere (MUA). Numerical experiments of sudden stratospheric warming (SSW) events are performed for climatological conditions typical for January and February using meteorological reanalysis data from the UK MET Office in the MUA model averaged over the years 1992-2011 with the easterly phase of quasi-biennial oscillation (QBO). The simulation shows that an increase in the OGW amplitudes occurs at altitudes higher than 30 km in the Northern Hemisphere after SSW. The OGW amplitudes have maximums at altitudes of about 50 km over the North American and European mountain systems before and during SSW, as well as over the Himalayas after SSW. At high latitudes of the Northern Hemisphere, significant (up to 50-70%) variations in the amplitudes of stationary planetary waves (SPWs) are observed during and after the SSW. Westward travelling NAMs have local amplitude maximums not only in the Northern Hemisphere, but also in the Southern Hemisphere, where there are waveguides for the propagation of these modes. Calculated variations of SPW and NAM amplitudes correspond to changes in the mean temperature and wind fields, as well as the Eliassen-Palm flux and atmospheric refractive index for the planetary waves, during SSW. Including OGW thermal and dynamical effects leads to an increase in amplitude (by 30-70%) of almost all SPWs before and during SSW and to a decrease (up to 20-100%) after the SSW at middle and high latitudes of the Northern Hemisphere.

  19. 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. 2015 BMJ Publishing Group Ltd.

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

    DEFF Research Database (Denmark)

    Nyegaard, Mette; Overgaard, Michael Toft; Sondergaard, M.T.

    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...... 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...... 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...

  1. CARDIOVASCULAR CAUSES OF SUDDEN DEATH- AN AUTOPSY STUDY

    Directory of Open Access Journals (Sweden)

    Deepu Thankappan

    2016-10-01

    Full Text Available BACKGROUND Present study “Cardiovascular Causes of Sudden Death- An Autopsy Study” was a cross-sectional study conducted in Department of Forensic Medicine, Government Medical College, Kottayam, during the time period from June 1 st 2013 to June 1 st 2014. The objective of the study was to find out the cardiovascular causes of sudden deaths and to correlate the postmortem findings with the histopathological examination. 57 cases brought for postmortem examination with history suggestive of sudden natural death were taken into the study and those cases observed to have a cardiovascular cause of sudden death during autopsy were further examined and their heart specimens were subjected to histopathological examination. Then, the sociodemographic factors, postmortem findings and histopathological findings were correlated and analysed. MATERIALS AND METHODS 57 cases brought for autopsy at Department of Forensic Medicine, Government Medical College, Kottayam from 01.06.2013 to 31.05.2014 were autopsied and subjected to histopathological examination of the heart. The socio-demographic data were collected; they were analyzed and correlated with the postmortem and histopathological findings. RESULTS Out of the 57 subjects who were taken into the study, maximum number of Sudden natural deaths were in the 36-50 year age group (42.2%, 33.3% in the 51-65 year age group and 14% of cases were in the 66-80 year age group. CONCLUSION Histopathological examination of the samples showed myocardial infarction in 33.3% of cases; chronic ischaemic heart disease in 56.1% of cases and myocarditis in 19.3% of cases. The major cardiovascular cause of sudden death was ascertained as Coronary artery disease.

  2. Sudden entanglement death, and ways to avoid it

    International Nuclear Information System (INIS)

    Eberly, J.H.; Ting Yu

    2005-01-01

    We report that non-communicating but entangled qubit pairs are almost universally liable to sudden entanglement death. In the presence of minor and purely local environmental noises their mixed-state entanglement may abruptly become zero long before the noises are able to destroy the local qubit coherence. Despite the inability of unitary transformations to alter entanglement, for example of Werner states, unitary transformations have been found to delay or defeat the sudden death event. These results upset the conventional understanding that entanglement lifetime can be estimated from qubit lifetime. This is not even approximately or qualitatively true. (author)

  3. 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.

  4. 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.

  5. Necessary and sufficient conditions for big bangs, bounces, crunches, rips, sudden singularities and extremality events

    International Nuclear Information System (INIS)

    Cattoen, Celine; Visser, Matt

    2005-01-01

    Until recently, the physically relevant singularities occurring in FRW cosmologies had traditionally been thought to be limited to the 'big bang', and possibly a 'big crunch'. However, over the last few years, the zoo of cosmological singularities considered in the literature has become considerably more extensive, with 'big rips' and 'sudden singularities' added to the mix, as well as renewed interest in nonsingular cosmological events such as 'bounces' and 'turnarounds'. In this paper we present an extensive catalogue of such cosmological milestones, both at the kinematical and dynamical level. First, using generalized power series, purely kinematical definitions of these cosmological events are provided in terms of the behaviour of the scale factor a(t). The notion of a 'scale-factor singularity' is defined, and its relation to curvature singularities (polynomial and differential) is explored. Second, dynamical information is extracted by using the Friedmann equations (without assuming even the existence of any equation of state) to place constraints on whether or not the classical energy conditions are satisfied at the cosmological milestones. We use these considerations to derive necessary and sufficient conditions for the existence of cosmological milestones such as bangs, bounces, crunches, rips, sudden singularities and extremality events. Since the classification is extremely general and, modulo certain technical assumptions, is complete, the corresponding results are to a high degree model independent: in particular, we provide a characterization of the class of bangs, crunches and sudden singularities for which the dominant energy condition is satisfied

  6. Sudden death related to advanced coronary atherosclerosis in mini-pigs

    International Nuclear Information System (INIS)

    Jacobsson, L.; Lundholm, L.; Wingren, G.

    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 β-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 β-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. (author)

  7. Sudden Infant Death Syndrome — the overview of the problem from XXI century

    Directory of Open Access Journals (Sweden)

    L.A. Kravtsova

    2011-01-01

    Full Text Available Sudden infant death syndrome (SIDS is sudden non-violent death of apparently healthy infant with absence of adequate reasons of the death according to the medical history and pathomorphological examination. At the present times SIDS is one of the most significant causes of postneonatal infants’ mortality in most developed countries in the world. The main and stable characteristics of SIDS are: death during the sleep and, mainly, in prone position; the peak of SIDS cases is in 2–4 months old; it frequently occurs in premature children and infants with low inborn body weight and in boys (60%; symptoms of mild respiratory infection precede SIDS. Clinical data, analysis of heart rate and breathing in children dead by SIDS afterwards, and experiments with animal models show that the leading pathologic mechanism of SIDS are cardio-respiratory disorders. The program of prophylaxis of ominous states and SIDS includes definition of risk groups with typical clinical and instrumental criteria and observation of children from risk groups.Key words: sudden infant death syndrome, mechanisms, prophylaxis.

  8. Effects of a lifting belt on spine moments and muscle recruitments after unexpected sudden loading.

    Science.gov (United States)

    Lavender, S A; Shakeel, K; Andersson, G B; Thomas, J S

    2000-06-15

    Ten men and eight women participated in a repeated-measures experiment in which sudden loads were applied unexpectedly to a container held in the hands. Three independent variables were investigated: lifting belt use, preload, and load symmetry. To determine whether a lifting belt would help protect the spine in sudden symmetric and asymmetric loading situations. Unexpected loading events have long been associated with the onset of back pain. Based on work showing that lifting belts restrict motion of the torso, the hypothesis was that a lifting belt would stiffen the spine, thereby protecting its supporting tissues. A weight, equal to 7.5% of the subjects' trunk extension force, was allowed to fall 1 m before the bottom of a box held by blindfolded subjects was pulled. Kinetic and kinematic data, obtained from two force plates and a magnetic motion measurement system, were used in a three-dimensional, dynamic, linked-segment biomechanical model to calculate spine moments. Electromyogram data were simultaneously obtained from eight trunk muscles. The belt reduced the forward bending of the spine during the symmetric loadings. In the men, the belt also reduced the forward flexion moment acting on the spine. The belt restricted lateral bending in the women and men, when the box was preloaded. The peak electromyogram amplitudes from posterior contralateral erector spinae and latissimus dorsi muscles increased during the asymmetric loadings, whereas three ipsilateral muscles were less active. The conflicting moment and electromyographic results, combined with the influence of load symmetry, preload, and gender make the benefits of the lifting belt difficult to delineate. Although the data support the hypothesis that the belt stiffens the torso's response to sudden loading, the effects are small, and considerable individual differences exist. The findings show that during unexpected sudden loading, a belt may reduce the net external moment loading. At the same time the

  9. 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.

  10. Intratympanic glucocorticosteroid therapy for idiopathic sudden hearing loss

    Science.gov (United States)

    Lai, Dan; Zhao, Fei; Jalal, Nasim; Zheng, Yun

    2017-01-01

    Abstract Background and objective: Glucocorticoids are the standard treatment for idiopathic sudden sensorineural hearing loss (ISSNHL), but whether intratympanic or systemic therapy is superior remains controversial. Previous meta-analyses of this question have omitted key clinical trials or included observational studies. Methods: English-language randomized controlled trials in OvidSP, PubMed, Embase, CINAHL, and the Cochrane Library comparing intratympanic versus systemic glucocorticoid therapy for ISSNHL were meta-analyzed using RevMan 5.3. The primary outcome of interest was improvement in pure tone average (PTA) threshold. Results: Six trials involving 248 patients receiving intratympanic steroids and 236 receiving systemic steroids were meta-analyzed. PTA thresholds were similar between the 2 groups at 3 months after therapy initiation (mean difference, 0.24; 95% confidence interval [CI] −2.43 to 2.91, P = .86; I2 = 54%, P = .07, random-effects model). PTA thresholds were also similar at 6 months (mean difference, 4.69, 95% CI −5.84 to 15.22, P = .38), although the results showed extremely high heterogeneity (I2 = 98%). Sensitivity analysis indicated that a single trial containing 250 patients provided the strongest evidence for equivalence between the 2 types of therapy. Rates of recovery within 3 months (defined as PTA improvement >10 dB) were similar between the 2 types of therapy (odds ratio 0.92, 95% CI 0.59–1.43, P = .70), with no significant heterogeneity in the pooled data (I2 = 1%, P = .40). Conclusion: Intratympanic and systemic steroids’ therapies appear to show similar short-term efficacy for restoring hearing in patients with ISSNHL. Intratympanic therapy may reduce systemic side effects associated with steroid use. PMID:29390288

  11. 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.

  12. Estimation of hydraulic jump characteristics of channels with sudden diverging side walls via SVM.

    Science.gov (United States)

    Roushangar, Kiyoumars; Valizadeh, Reyhaneh; Ghasempour, Roghayeh

    2017-10-01

    Sudden diverging channels are one of the energy dissipaters which can dissipate most of the kinetic energy of the flow through a hydraulic jump. An accurate prediction of hydraulic jump characteristics is an important step in designing hydraulic structures. This paper focuses on the capability of the support vector machine (SVM) as a meta-model approach for predicting hydraulic jump characteristics in different sudden diverging stilling basins (i.e. basins with and without appurtenances). In this regard, different models were developed and tested using 1,018 experimental data. The obtained results proved the capability of the SVM technique in predicting hydraulic jump characteristics and it was found that the developed models for a channel with a central block performed more successfully than models for channels without appurtenances or with a negative step. The superior performance for the length of hydraulic jump was obtained for the model with parameters F 1 (Froude number) and (h 2- h 1 )/h 1 (h 1 and h 2 are sequent depth of upstream and downstream respectively). Concerning the relative energy dissipation and sequent depth ratio, the model with parameters F 1 and h 1 /B (B is expansion ratio) led to the best results. According to the outcome of sensitivity analysis, Froude number had the most significant effect on the modeling. Also comparison between SVM and empirical equations indicated the great performance of the SVM.

  13. Solar flare effects and storm sudden commencement even in ...

    African Journals Online (AJOL)

    1998-05-08

    Variations in the three components of geomagnetic field were observed at the twenty-two geomagnetic Euro-African Observatories during the solar flare that occurred on the 6 May, 1998 at 0080UT and storm sudden commencement that took place on May 8, 1998 at 15.00 UT. The geomagnetic field on 6 May, 1998 was ...

  14. 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,...

  15. Sudden cardiac arrest risk in young athletes | Gradidge | South ...

    African Journals Online (AJOL)

    Underlying cardiac abnormalities are the main cause of unexpected death in athletes on field. These abnormalities have been associated with a previous history of syncope, a family history of sudden cardiac arrest (SCA), cardiac murmur, a history of over-exhaustion post exercise and ventricular tachyarrhythmia during ...

  16. Protecting Trees from Sudden Oak Death before Infection

    Science.gov (United States)

    C. Lee; Y. Valachovic; M. Garbelotto

    2010-01-01

    Phytophthora ramorum, an introduced invasive plant pathogen that causes sudden oak death, has killed over a million tanoak, coast live oak, Shreve oak, and California black oak trees along the California coastal region from Monterey through Humboldt Counties. Most trees infected with P. ramorum will eventually die, including...

  17. Sudden Cardiac Death in Nigeria: Pathophysiology and Evidence ...

    African Journals Online (AJOL)

    International Journal of Basic, Applied and Innovative Research ... There is therefore a need to research into the direct causes of sudden cardiac death in Nigeria with the aim of providing evidence-based information to the policy makers for sustainable social environmental and behavioral modification that will nick this ugly ...

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

    Directory of Open Access Journals (Sweden)

    Cong Ma

    2016-03-01

    Full Text Available 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.

  19. 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

  20. 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

  1. Declining risk of sudden death in heart failure

    DEFF Research Database (Denmark)

    Shen, Li; Jhund, Pardeep S.; Petrie, Mark C.

    2017-01-01

    BACKGROUND The risk of sudden death has changed over time among patients with symptomatic heart failure and reduced ejection fraction with the sequential introduction of medications including angiotensin-converting-enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, and mineralocorti...

  2. Sudden cardiac death and coronary disease in the young

    DEFF Research Database (Denmark)

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

    2017-01-01

    BACKGROUND: Sudden cardiac death caused by coronary artery disease (CAD-SCD) is the most frequent cause of SCD in persons characteristics and autopsy findings of the heart among 18-35 and 36-49year old CAD-SCD cases. METHODS: We...... to death in young CAD-SCD cases, which may enable clinicians to prevent these tragic deaths....

  3. 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...

  4. Incidence of ventricular arrhythmias, brady-arrhythmias and sudden ...

    African Journals Online (AJOL)

    Ventricular arrhythmias (VAS), Including ventricular tachycardia (VT), ventricular fibrillation (VF) and Brady-arrhythmias, are life-threatening complications of acute myocardial infarction (MI). Objective: To study the incidence of ventricular arrhythmias, brady-arrhythmias and Sudden Cardiac Death (SCD) in Sudanese ...

  5. Relationship between coronary atherosclerosis and 'sudden cardiac death'

    International Nuclear Information System (INIS)

    Lundholm, C.E.; Sundbom, L.; Lundholm, L.

    1989-01-01

    Coronary arteriosclerosis in mini-pigs was produced by combination of hypercholesterolemia and twofold X irradiation of the cardiac region. 15-21 weeks following irradiation 40% of the adult animals and 58% of the juvenils died of 'sudden cardiac death'. The mortality rate decreased significantly after application of the calcium-channel blocking agent nifedipine

  6. Steroid Use in Idiopathic Sudden Sensorineural Hearing Loss: What ...

    African Journals Online (AJOL)

    Idiopathic sudden sensorineural hearing loss is a disease of unknown etiology. Controversy in the literature argues whether the condition should be treated by steroid therapy. In this case study, a Medline literature search was completed to find out if there is any evidence to support its use in this condition.

  7. Sudden oak death in California: what is the potential?

    Science.gov (United States)

    Tara M. Barrett; Demetrios Gatziolis; Jeremy S. Fried; Karen L. Waddell

    2006-01-01

    Sudden oak death, a disease associated with the pathogen Phytophthora ramorum, has a large number of shrub and tree host species. Three of the tree species must susceptible to mortality from the disease, California black oak (Quercus kelloggii), coast live oak (Quercus agrifolia), and tanoak (...

  8. Circumvention of suddenly appearing obstacles in young and older adults

    NARCIS (Netherlands)

    Pijnappels, M.; Kingma, I.; Van Dieën, J. H.

    2010-01-01

    Reduced ability to circumvent an obstacle, which is noticed only shortly before collision, could be a cause of falls and injury, especially in older adults. In this study, we investigated differences in strategies and their characteristics between young and older adults when circumventing a suddenly

  9. 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.)

  10. Cardiac symptoms before sudden cardiac death caused by hypertrophic cardiomyopathy

    DEFF Research Database (Denmark)

    Lynge, Thomas Hadberg; Risgaard, Bjarke; Jabbari, Reza

    2016-01-01

    AIMS: Hypertrophic cardiomyopathy (HCM) is a frequent cause of sudden cardiac death (SCD) among the young (SCDY). The aim of this study was to characterize symptoms before SCDY due to HCM. METHODS AND RESULTS: Through review of all death certificates, we identified all SCDs in Danes aged 1-35 years...

  11. CAUSES OF SUDDEN NATURAL DEATH: A MEDICO-LEGAL ...

    African Journals Online (AJOL)

    2012-10-10

    Oct 10, 2012 ... CAUSES OF SUDDEN NATURAL DEATH: A MEDICO-LEGAL AUTOPSY STUDY OF MEDICAL CASES IN AN. AFRICAN REFERRAL ... Medico-legal (coroner's) autopsies are post-mortem examinations performed at the ..... worldwide causes of this lesion are alcohol abuse, viral hepatitis especially in ...

  12. About a cocaine-associated sudden death casework.

    Science.gov (United States)

    Pileggi, P; Teatino, A; La Marca, A; Barbaro, A

    2004-12-02

    A man 24-year-old died suddenly while he was doing shopping. It was supposed that the death was caused by ictus or by cardiac pathology. During the autopsy, some biological samples were taken (hair, urine, blood and lachrymal liquid) for the toxicological analysis and also the heart, some fragments from the liver, lungs, spleen, and kidneys for the histo-pathological analysis.

  13. Sudden cardiac death in Nigerians - The Ile - Ife experience | Rotimi ...

    African Journals Online (AJOL)

    Methods: A review of all cases of medico-legal autopsies performed at the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria, on cases of ... Cases of coronary heart disease and myocardial infarction played significant roles as causes of sudden cardiac death, indicating that their incidence may not be ...

  14. 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.

  15. Picture quiz: a case of sudden severe chest pain.

    Science.gov (United States)

    Rabia, Mustafa Abu; Sullivan, P; Stivaros, Stavros M

    2007-01-01

    An 18-year-old male with no previous medical history presented to hospital with sudden onset of acute epigastric pain radiating to the anterior chest wall and both shoulders. There was no history of recent trauma and he had not been vomiting.

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    Sudden infant death syndrome (SIDS) still accounts for considerable numbers of unexpected infant deaths in many countries. While numerous theories have been advanced to explain these events, it is increasingly clear that this group of infant deaths results from the complex interaction of a variety...

  17. Sudden and unexpected childhood deaths investigated at the ...

    African Journals Online (AJOL)

    MEDICINE AND THE LAW ... A retrospective descriptive case audit was conducted at the Pretoria Medico-Legal Laboratory (PMLL), SA, from 1 January 2007 .... PMLL is 3:1. Most deaths (51.0%) occurred in children aged 1 - 5 years. In Ireland (1994 -. 2008), 5% of all deaths in children under the age of 5 were sudden and ...

  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. [Genetic constitution analysis of idiopathic sudden hearing loss].

    Science.gov (United States)

    Bora, Adem; Altuntaş, Emine Elif; Ozdemir, Oztürk; Uysal, Ismail Onder; Müderris, Suphi

    2010-01-01

    The purpose of this research is to understand the etiology of sudden hearing loss due to genetic factors in Turkish people. Determination of these genetic factors and better understanding of molecular pathogenesis may guide more realistic planning and treatment recommendations. Forty patients (Group 1; 19 males, 21 females; mean age 37.9+/-15.6 years; range 9 to 76 years) who presented with sudden hearing loss to the Ear, Nose and Throat Clinic of Medical Faculty Hospital of Cumhuriyet University between January 2008 and June 2009, and were diagnosed with sudden hearing loss through history, physical examination and review of audiometric findings, and 20 healthy volunteers (Group 2; 14 males, 6 females; mean age 31.7+/-4.4 years; range 24 to 43 years) for the control group were included in this study. All Patients were evaluated by the genetic clinic for the GJB2, GJB3, GJB6 and WFS1 gene using multiplex ligation-dependent probe amplification (MLPA) method mutation analysis. No difference was found in the peripheral blood sample analyses of the two groups at WFS1 exon 8 and connexin 26, 30 and 31 gene zones using the MLPA method with respect to heterozygous mutation (p=0.291, p>0.05). In four patients in group 1 heterozygous mutation was detected at the target gene zone. Heterozygous mutation was in the WFS1 exon 8 zone in two patients; and in the WFS1 exon 1 zone in other two patients. Sudden hearing loss studies in the future should include connexin 26, connexin 30 and other gene mutations that may affect the function of the gap-junction located in the region of the cochlea stria vascularis (stV), basal membrane (BM), spiral limbus (Li) and spiral ligament (SL). These studies should be performed on larger series, and should include family members of patients with sudden hearing loss.

  20. Sudden unexpected death in children with congenital heart defects.

    Science.gov (United States)

    Jortveit, Jarle; Eskedal, Leif; Hirth, Asle; Fomina, Tatiana; Døhlen, Gaute; Hagemo, Petter; Tell, Grethe S; Birkeland, Sigurd; Øyen, Nina; Holmstrøm, Henrik

    2016-02-14

    Congenital heart defects (CHDs) are the most common birth defects and are an important cause of death in children. The fear of sudden unexpected death has led to restrictions of physical activity and competitive sports. The aim of the present study was to investigate the rate of sudden unexpected deaths unrelated to surgery in children 2-18 years old with CHDs and, secondarily, to determine whether these deaths were related to cardiac disease, comorbidity, or physical activity. To identify children with CHDs and to determine the number of deaths, data concerning all 9 43 871 live births in Norway in 1994-2009 were retrieved from the Medical Birth Registry of Norway, the Cardiovascular Disease in Norway project, the Oslo University Hospital's Clinical Registry for Congenital Heart Defects and the Norwegian Cause of Death Registry. Survivors were followed through 2012, and information for the deceased children was retrieved from medical records at Norwegian hospitals. Among 11 272 children with CHDs, we identified 19 (0.2%) children 2-18 years old who experienced sudden unexpected deaths unrelated to cardiac surgery. A cardiac cause of death was identified in seven of these cases. None of the children died during physical activity, whereas two children survived cardiac arrest during sports. Sudden unexpected death was infrequent among children with CHDs who survived 2 years of age. Comorbidity was common among the children who died. This study indicates that sudden unexpected death in children with CHDs rarely occurs during physical activity. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  1. 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

  2. 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. .

  3. Data report of ROSA/LSTF experiment SB-HL-12. 1% hot leg break LOCA with SG depressurization and gas inflow

    International Nuclear Information System (INIS)

    Takeda, Takeshi

    2016-01-01

    An experiment SB-HL-12 was conducted on February 24, 1998 using the Large Scale Test Facility (LSTF) in the Rig of Safety Assessment-V (ROSA-V) Program. The ROSA/LSTF experiment SB-HL-12 simulated a 1% hot leg small-break loss-of-coolant accident in a pressurized water reactor under assumptions of total failure of high pressure injection system and non-condensable gas (nitrogen gas) inflow to the primary system from accumulator (ACC) tanks of emergency core cooling system (ECCS). Steam generator (SG) secondary-side depressurization by fully opening the relief valves in both SGs as an accident management (AM) action was initiated immediately after maximum surface temperature of simulated fuel rod reached 600 K. Auxiliary feedwater injection into the secondary-side of both SGs was started immediately after the initiation of AM action. After the onset of AM action due to first core uncovery by core boil-off, the primary pressure decreased following the SG secondary-side pressure, causing core mixture level swell. The fuel rod surface temperature then increased up to 635 K. Second core uncovery by core boil-off took place before loop seal clearing (LSC) induced by steam condensation on ACC coolant injected into cold legs. The core liquid level recovered rapidly after the LSC. The fuel rod surface temperature then increased up to 696 K. The pressure difference became larger between the primary and SG secondary sides after the ACC tanks started to discharge nitrogen gas, which resulted in no actuation of LPI system of ECCS during the experiment. Third core uncovery by core boil-off occurred during the reflux condensation in the SG U-tubes under nitrogen gas inflow. The core power was automatically decreased by the LSTF core protection system when the maximum fuel rod surface temperature exceeded 908 K. The obtained data would be useful to define the conditions for counterpart testing of other integral test facilities to address scaling problems through thermal

  4. Local measurement and numerical calculation on turbulent two-phase flow in a vertical pipe with sudden expansion

    International Nuclear Information System (INIS)

    Kondo, Koichi; Yoshida, Kenji; Okawa, Tomio; Kataoka, Isao

    2004-01-01

    Experiment and numerical calculation were carried out for upward, turbulent bubbly two-phase flow in a vertical pipe with an axisymmetric sudden expansion, which is one of the typical multi-dimensional channel geometries. The void fraction, the liquid velocity and turbulent intensity along the flow direction below and the above the sudden expansion point were measured for various turbulent flow conditions by using a point-electrode resistivity probe and a hot-film anemometry probe. They showed quite complicated behaviors depending upon flow rates of gas and liquid phases and bubble size. In particular, the geometry of sudden expansion affected on the bubble behaviors in multi-dimensional two-phase flow, such as the bubble-stagnation, the bubble-deformation, the enhancement and suppression effects due to the two-phase turbulence etc. Through the measurements, fundamental parameters of the two-phase flow were clarified for the sudden expansion channel. Moreover, a three-dimensional one-way bubble tracking simulation of a single bubble behavior in turbulent flow field along the downstream of the sudden expansion was also demonstrated where equation of motion of bubble was solved by assuming appropriate constitutive models and turbulence model. Based on the trajectories of large number of bubbles, the void fraction distribution was predicted in this calculation. It concretely revealed that the lift force and the two-phase turbulence model were the most important parameters in determining the multi-dimensional void fraction distribution and the calculation should be considered by using the measured experimental data. (author)

  5. Forecasting sudden changes in environmental pollution patterns.

    Science.gov (United States)

    Olascoaga, María J; Haller, George

    2012-03-27

    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.

  6. 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

  7. 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.

  8. Sudden Bilateral Sensorineural Hearing Loss Secondary to Cerebral Venous Thrombosis

    Directory of Open Access Journals (Sweden)

    Muhammad-Nu’aim Ishak

    2018-03-01

    Full Text Available Introduction: Sudden sensorineural hearing loss (SSNHL is an important otological emergency. Up to 90% of the cases are idiopathic. Cerebral venous thrombosis (CVT is an extremely rare identifiable cause as it only represents 0.5% of all strokes.   Case Report: In this paper, an unusual case of bilateral SSNHL secondary to bilateral CVT with rapid and complete recovery is reported. The patient presented with sudden bilateral hearing loss associated with some neurological symptoms. Initial computed tomography (CT venography revealed a CVT of bilateral transverse sinuses. The patient was started on an anticoagulant and imaging was repeated after five days, revealing the absence of the thrombosis. Serial pure tone audiometry (PTA showed complete recovery of bilateral hearing within 10 days.   Conclusion: Early detection and intervention may fasten hearing recovery and improve the quality of life. The immediate restoration of venous blood flow and intracranial pressure may lead to the complete recovery of bilateral hearing loss.

  9. Sudden death in a young patient with atrial fibrillation

    Directory of Open Access Journals (Sweden)

    María Tamargo

    2017-08-01

    Full Text Available Sudden cardiac death (SCD in young patients without structural heart disease is frequently due to inherited channelopathies such as long QT syndrome (LQTS, Brugada syndrome or Catecholaminergic polymorphic ventricular tachycardia. Accordingly, the addition of genetic testing to clinical data may be useful to identify the cause of the sudden death in this population. Mutations in the KCNQ1 encoded Kv7.1 channel are related to type 1 LQTS, familial atrial fibrillation (AF, short QT syndrome, and SCD. We present a clinical case where the presence of AF after resuscitation in a young man with cardiac arrest was the key clinical data to suspect an inherited disorder and genetic testing was the main determinant for identifying the cause of the cardiac arrest. The KCNQ1 p.Arg231His mutation explained the combined phenotype of AF and susceptibility to ventricular arrhythmias. The case highlights the importance of continued research in genetics and molecular mechanisms of channelopathies.

  10. Sudden polarization effect in methyl-substituted twisted polyenes

    International Nuclear Information System (INIS)

    Baraldi, I.; Bruni, M.C.; Momicchioli, F.; Ponterini, G.

    1981-01-01

    Sudden polarization effect was investigated for a special type of nonsymmetric biradical systems, i.e. terminally twisted polyenes methyl substituted at the rotated CH 2 group. Systems with 2 to 4 conjugated double bonds were studied. Dipole moments of S 0 , S 1 and S 2 states were calculated within the framework of the INDO approximations, by using a dual basis of SCF MOs (open shell and closed shell) and performing differently sized CIs (selected with reference to the basic 3 x 3 CI biradical description). The resulting excited-state polarization characteristics (size and suddenness) are discussed with reference to the previously studied unsubstituted polyenes. In this respect the most important point is that CH 3 substitution at the terminal twisted methylene markedly enhances the polarization size (approximately 2D). This indicates that small perturbations occurring at one radical site may cause unexpectedly large changes in charge distributions of excited biradicals. (author)

  11. 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

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

    Science.gov (United States)

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

    2016-06-22

    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. A previously healthy 12-year-old male West Highland white terrier was found dead during its 1-week stay in a kennel. The dog was known to have a cardiac murmur. On necropsy, a pedunculated neoplasia was found attached to the interventricular aspect of the left ventricular outflow tract, resulting in almost complete obstruction of the aorta. As this was the only abnormality identified, the tumor was considered as the cause of sudden death. Histopathologic findings were compatible with a myxoma. Benign intraluminal tumors of the heart are very rare in dogs, but may have fatal consequences. Echocardiography could have revealed the cause of the cardiac murmur of this previously asymptomatic dog. Surgical removal could have been possible, as the tumor was pedunculated.

  13. Sudden acquired retinal degeneration syndrome in western Canada: 93 cases.

    Science.gov (United States)

    Leis, Marina L; Lucyshyn, Danica; Bauer, Bianca S; Grahn, Bruce H; Sandmeyer, Lynne S

    2017-11-01

    This study reviewed clinical data from dogs diagnosed with sudden acquired retinal degeneration syndrome (SARDS) in western Canada. Medical records from the Western College of Veterinary Medicine from 2002 to 2016 showed that 93 cases of SARDS were diagnosed based on presentation for sudden blindness and a bilaterally extinguished electroretinogram. The most common pure breeds were the miniature schnauzer, dachshund, and pug. The mean age at diagnosis was 8.1 years and males and females were equally affected. Most of the dogs were presented with normal non-chromatic, but abnormal chromatic pupillary light reflexes. The incidence of retinal degeneration as detected via ophthalmoscopy increased over time after SARDS diagnosis. Polyuria, polydipsia, polyphagia, weight gain, elevated liver enzyme values, isosthenuria, and proteinuria were common clinical and laboratory findings. Chromatic pupillary light reflex testing may be more valuable than non-chromatic pupillary light testing in detecting pupil response abnormalities in dogs with SARDS, although electroretinography remains the definitive diagnostic test.

  14. Familial Atrial Septal Defect and Sudden Cardiac Death

    DEFF Research Database (Denmark)

    Ellesøe, Sabrina Gade; Johansen, Morten Munk; Bjerre, Jesper Vandborg

    2016-01-01

    OBJECTIVE: Atrial septal defect (ASD) is the second most common congenital heart defect (CHD) and is observed in families as an autosomal dominant trait as well as in nonfamilial CHD. Mutations in the NKX2-5 gene, located on chromosome 5, are associated with ASD, often combined with conduction...... disturbances, cardiomyopathies, complex CHD, and sudden cardiac death as well. Here, we show that NKX2-5 mutations primarily occur in ASD patients with conduction disturbances and heritable ASD. Furthermore, these families are at increased risk of sudden cardiac death. RESULTS: We screened 39 probands...... with familial CHD for mutations in NKX2-5 and discovered a novel mutation in one family (2.5%) with ASD and atrioventricular block. A review of the literature revealed 59 different NKX2-5 mutations in 202 patients. Mutations were significantly more common in familial cases compared to nonfamilial cases (P = 7...

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

    DEFF Research Database (Denmark)

    Bjune, Thea; Risgaard, Bjarke; Kruckow, Line

    2018-01-01

    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...... is displayed in a considerable proportion. SCD with positive toxicology had higher rate of SADS, suggesting that the compounds may play a proarrhythmic role in these cases....

  16. 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.

  17. Statistical inferences for bearings life using sudden death test

    Directory of Open Access Journals (Sweden)

    Morariu Cristin-Olimpiu

    2017-01-01

    Full Text Available In this paper we propose a calculus method for reliability indicators estimation and a complete statistical inferences for three parameters Weibull distribution of bearings life. Using experimental values regarding the durability of bearings tested on stands by the sudden death tests involves a series of particularities of the estimation using maximum likelihood method and statistical inference accomplishment. The paper detailing these features and also provides an example calculation.

  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. A vortex dynamics perspective on stratospheric sudden warmings

    OpenAIRE

    Matthewman, N. J.

    2009-01-01

    A vortex dynamics approach is used to study the underlying mechanisms leading to polar vortex breakdown during stratospheric sudden warmings (SSWs). Observational data are used in chapter 2 to construct climatologies of the Arctic polar vortex structure during vortex-splitting and vortex-displacement SSWs occurring between 1958 and 2002. During vortex-splitting SSWs, polar vortex breakdown is shown to be typically independent of height (barotropic), whereas breakdown during vor...

  20. Disseminated cryptococcosis and sudden death. Report of an autopsy case.

    Science.gov (United States)

    Zappi, E; Zappi, M; Zugibe, F T

    1995-03-01

    We report a case of sudden death due to terminal cryptococcal pneumonia in a patient not suspected to have AIDS. The correct diagnosis was found only by microscopic examination and serologic workup, illustrating the hazards faced by forensic pathologists and their assistants working without adequate information about the bodies under study. This case illustrates the need for the highest levels of caution and compliance with universal precautionary measures during autopsy procedures in the present days of the AIDS epidemic.

  1. The Effects of Prognostic Factors in Idiopathic Sudden Hearing Loss.

    Science.gov (United States)

    Bulğurcu, Suphi; Şahin, Behçet; Akgül, Gökhan; Arslan, İlker Burak; Çukurova, İbrahim

    2018-01-01

    Introduction  Sudden hearing loss is one of the otologic emergencies. The treatment of this disease is affected negatively by some prognostic factors. Objective  In this study, the effects of early treatment initiation in patients with idiopathic sudden hearing loss and of prognostic factors in early treated patients were investigated. Methods  Out of the 216 patients admitted between September 2007 and September 2015, 154 were identified as having idiopathic sudden hearing loss; they were followed-up for a mean time of 7.4 months, and evaluated retrospectively. The effects of several parameters on the success of the treatment were statistically evaluated, such as the time the treatment was initiated, being of the female gender, the severity of the hearing loss, having descending type audiogram patterns, being older than 60 years old, and the co-presence of vertigo. Results  Success rates were found to be significantly higher in idiopathic hearing loss patients that were admitted within the first week ( p  hearing loss. However, the outcomes were found to be similar when patients admitted within the first 3 days and 4-7 days after the occurrence of the hearing loss were compared ( p  > 0.05). Parameters such as female gender, severe hearing loss, descending type audiogram, being older than 60 years old, and co-presence of vertigo didn't reveal statistically significant effects on the outcome ( p >0.05). Conclusion  The aforementioned prognostic factors, which are well-known in the literature, did not have significant effects when the idiopathic sudden hearing loss treatment was initiated within the first 7 days of the onset of the hearing loss.

  2. Giant left anterior descending artery aneurysm resulting in sudden death

    Directory of Open Access Journals (Sweden)

    Chan-Hee Lee

    2016-07-01

    Full Text Available Coronary artery aneurysm is a rare congenital or vascular inflammation-based anomaly for which the clinical course and optimal timing of treatment remain unclear. Here, we report a case of sudden death caused by a giant coronary artery aneurysm of the left anterior descending artery that presented with chest pain. This case suggests that urgent interventional or surgical repair is needed when a large coronary aneurysm presents with acute ischemic symptoms.

  3. 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.

  4. [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.

  5. Sudden cardiac death: still more questions than answers.

    Science.gov (United States)

    Henry, P D; Pacifico, A

    1997-12-01

    Sudden cardiac death is the leading cause of death in industrialized countries. It is most frequently due to ventricular tachyarrhythmias occurring in the presence of coronary heart disease, but mechanisms linking sudden death to coronary atherosclerosis are still unclear. In autopsy studies of sudden death patients, the incidence of acute thrombotic coronary occlusions has varied between 4 and 74%. In over 600 consecutive patients with implantable cardioverter-defibrillators, we observed that appropriate shocks for electrogram-verified ventricular tachyarrhythmias was only very rarely followed by signs of acute myocardial infarction (theory of fatal arrhythmias. Cellular hypertrophy compensating for cell loss due to ischemia, intraventricular hypertension, cardiomyopathy, and myocarditis might play a role in arrhythmogenesis as evidenced by the fact that experimental induction and regression of hypertrophy are paralleled by changes in the inducibility of ventricular tachyarrhythmias. Atherogenic hyperlipidemias are associated with a systemic inflammatory response manifested by leukocytosis (lymphocytosis) and complex upregulations of proinflammatory-prothrombotic mediators, such as platelet-activating factor, cytokines, and hemostasis factors. The diurnal regulation of these mediators parallels circadian rhythms of coronary morbidity and mortality. Some upregulated mediators have been shown to exert direct arrhythmogenic effects. The potential contribution of hyperlipidemia-associated inflammatory factors to arrhythmogenesis is important, because it opens new molecular targets for antiarrhythmic drug design.

  6. How sudden is a compelling desire to void? An observational cystometric study on the suddenness of this sensation.

    Science.gov (United States)

    De Wachter, Stefan; Wyndaele, Jean-Jacques

    2008-04-01

    To evaluate whether a compelling desire to void (CDV) is always perceived suddenly, or whether it can result from the gradual build-up of bladder-filling sensations. The pattern of filling sensations was evaluated during standard cystometric bladder filling in 75 patients who complained of urgency and showed detrusor overactivity during cystometry. Cystometric filling ended when a CDV was reported. The 'warning volume' is defined as the difference in volume between the first perception of filling and the volume at CDV. Different patterns of bladder-filling sensations were reported. A CDV occurred suddenly, without a preceding sensation in 13% of the patients, whereas 66% reported at least two normal preceding filling sensations before a CDV. The bladder volume at the CDV was significantly smaller in patients that reported no or just one preceding sensation compared with those that reported the normal pattern of two or three sensations (P perception was reported was not different regardless of whether it was described as a first sensation of filling, a first desire or a CDV (P = 0.42). The warning volumes were not different between patients with one or no standardized filling sensations (P = 0.7), but they were significantly smaller than in patients with two or three filling sensations (P = 0.85). A CDV can occur suddenly if normal filling sensation is disturbed, but also gradually if normal filling sensation is preserved. In cases of disturbed filling sensation, the volume at CDV and the warning volume are significantly lower.

  7. 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.

  8. 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

    2018-03-01

    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.

  9. Reporting a sudden death due to accidental gasoline inhalation.

    Science.gov (United States)

    Martínez, María Antonia; Ballesteros, Salomé; Alcaraz, Rafael

    2012-02-10

    The investigation of uncertain fatalities requires accurate determination of the cause of death, with assessment of all factors that may have contributed to it. Gasoline is a complex and highly variable mixture of aliphatic and aromatic hydrocarbons that can lead to cardiac arrhythmias due to sensitization of the myocardium to catecholamines or acts as a simple asphyxiant if the vapors displace sufficient oxygen from the breathing atmosphere. This work describes a sudden occupational fatality involving gasoline. The importance of this petroleum distillate detection and its quantitative toxicological significance is discussed using a validated analytical method. A 51 year-old Caucasian healthy man without significant medical history was supervising the repairs of the telephone lines in a manhole near to a gas station. He died suddenly after inhaling gasoline vapors from an accidental leak. Extensive blistering and peeling of skin were observed on the skin of the face, neck, anterior chest, upper and lower extremities, and back. The internal examination showed a strong odor of gasoline, specially detected in the respiratory tract. The toxicological screening and quantitation of gasoline was performed by means of gas chromatography with flame ionization detector and confirmation was performed using gas chromatography-mass spectrometry. Disposition of gasoline in different tissues was as follows: heart blood, 35.7 mg/L; urine, not detected; vitreous humor, 1.9 mg/L; liver, 194.7 mg/kg; lung, 147.6 mg/kg; and gastric content, 116,6 mg/L (2.7 mg total). Based upon the toxicological data along with the autopsy findings, the cause of death was determined to be gasoline poisoning and the manner of death was accidental. We would like to alert on the importance of testing for gasoline, and in general for volatile hydrocarbons, in work-related sudden deaths involving inhalation of hydrocarbon vapors and/or exhaust fumes. Copyright © 2011 Elsevier Ireland Ltd. All rights

  10. 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.

  11. Breaking the bad news when sudden death occurs.

    Science.gov (United States)

    Von Bloch, L

    1996-01-01

    Notification of family when sudden death has occurred is often a highly stressful experience for hospital Emergency Department physicians and nursing personnel. This article will offer some guidelines to health care professionals in helping a deceased patient's family cope with the initial grief and loss that accompanies the unexpected death of a loved one. At the same time, an understanding of the wide range of emotional responses of bereaved survivors may case some of the anxiety Emergency Department staff members associate with "breaking the bad news."

  12. Should pacifiers be recommended to prevent sudden infant death syndrome?

    Science.gov (United States)

    Mitchell, E A; Blair, P S; L'Hoir, M P

    2006-05-01

    Our aim was to review the evidence for a reduction in the risk of sudden infant death syndrome (SIDS) with pacifier ("dummy" or "soother") use, to discuss possible mechanisms for the reduction in SIDS risk, and to review other possible health effects of pacifiers. There is a remarkably consistent reduction of SIDS with pacifier use. The mechanism by which pacifiers might reduce the risk of SIDS is unknown, but several mechanisms have been postulated. Pacifiers might reduce breastfeeding duration, but the studies are conflicting. It seems appropriate to stop discouraging the use of pacifiers. Whether it is appropriate to recommend pacifier use in infants is open to debate.

  13. [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. Copyright © 2016 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. 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.

  15. 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. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Examining the accuracy of the infinite order sudden approximation using sensitivity analysis

    Science.gov (United States)

    Eno, Larry; Rabitz, Herschel

    1981-08-01

    A method is developed for assessing the accuracy of scattering observables calculated within the framework of the infinite order sudden (IOS) approximation. In particular, we focus on the energy sudden assumption of the IOS method and our approach involves the determination of the sensitivity of the IOS scattering matrix SIOS with respect to a parameter which reintroduces the internal energy operator ?0 into the IOS Hamiltonian. This procedure is an example of sensitivity analysis of missing model components (?0 in this case) in the reference Hamiltonian. In contrast to simple first-order perturbation theory a finite result is obtained for the effect of ?0 on SIOS. As an illustration, our method of analysis is applied to integral state-to-state cross sections for the scattering of an atom and rigid rotor. Results are generated within the He+H2 system and a comparison is made between IOS and coupled states cross sections and the corresponding IOS sensitivities. It is found that the sensitivity coefficients are very useful indicators of the accuracy of the IOS results. Finally, further developments and applications are discussed.

  17. 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.

  18. Fluid structural response of axially cracked cylinders

    International Nuclear Information System (INIS)

    Garnich, M.R.; Simoneh, F.A.

    1985-01-01

    The fluid structural (FS) response of a cylindrical pressure vessel to a suddenly occurring longitudinal through-wall crack is predicted. The effects of vessel internals and depressurization of the compressed water on dynamic crack opening displacements are investigated. A three dimensional (3D) structural finite element model is used as a basis for the development of a two dimensional (2D) FS model. A slice of the vessel taken at the crack midspan and normal to the cylinder axis is modeled. Crack opening displacements are compared between the 2D and 3D models, between the different assumptions about fluid depressurization, and between the static and dynamic solutions. The results show that effects of dynamic amplification associated with the sudden opening of the crack in the cylinder are largely offset by the local depressurization of the fluid adjacent to the crack

  19. The risk assessment of sudden water pollution for river network system under multi-source random emission

    Science.gov (United States)

    Li, D.

    2016-12-01

    Sudden water pollution accidents are unavoidable risk events that we must learn to co-exist with. In China's Taihu River Basin, the river flow conditions are complicated with frequently artificial interference. Sudden water pollution accident occurs mainly in the form of a large number of abnormal discharge of wastewater, and has the characteristics with the sudden occurrence, the uncontrollable scope, the uncertainty object and the concentrated distribution of many risk sources. Effective prevention of pollution accidents that may occur is of great significance for the water quality safety management. Bayesian networks can be applied to represent the relationship between pollution sources and river water quality intuitively. Using the time sequential Monte Carlo algorithm, the pollution sources state switching model, water quality model for river network and Bayesian reasoning is integrated together, and the sudden water pollution risk assessment model for river network is developed to quantify the water quality risk under the collective influence of multiple pollution sources. Based on the isotope water transport mechanism, a dynamic tracing model of multiple pollution sources is established, which can describe the relationship between the excessive risk of the system and the multiple risk sources. Finally, the diagnostic reasoning algorithm based on Bayesian network is coupled with the multi-source tracing model, which can identify the contribution of each risk source to the system risk under the complex flow conditions. Taking Taihu Lake water system as the research object, the model is applied to obtain the reasonable results under the three typical years. Studies have shown that the water quality risk at critical sections are influenced by the pollution risk source, the boundary water quality, the hydrological conditions and self -purification capacity, and the multiple pollution sources have obvious effect on water quality risk of the receiving water body

  20. Oral steroid treatment for idiopathic sudden sensorineural hearing loss

    Science.gov (United States)

    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 followed for at least 3 months. Results: Young age, the presence of no other disease (diabetes, hypertension, or cardiovascular disease), treatment within 7 days of the onset of ISSHL, mild hearing loss, and audiograms with ascending curves had a statistically significant better hearing recovery. The average pure-tone audiometry (PTA) was 67.8±23.9 dB initially, and was improved between one month (51.6±28.7 dB) and 2 months post treatment (49.7±28.6 dB). The average last-visit PTA was 49.9±29.2 dB. Conclusion: Approximately one third of patients had full recovery in hearing, one third had partial recovery, and approximately one third did not recover from hearing loss. In addition, the hearing level remained relatively stable following 2 months of treatment. More than 2 months of oral steroid therapy for ISSHL is not recommended because no additional benefits were evidenced. PMID:25737170

  1. 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. 2015 BMJ Publishing Group Ltd.

  2. 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

  3. Sudden infant death following hexavalent vaccination: a neuropathologic study.

    Science.gov (United States)

    Matturri, L; Del Corno, G; Lavezzi, A M

    2014-03-01

    We examined a large number of sudden infant death syndrome victims in order to point out a possible causal relationship between a previous hexavalent vaccination and the sudden infant death. We selected 110 cases submitted to in-depth histological examination of the autonomic nervous system and provided with detailed clinical and environmental information. In 13 cases (11.8%) the death occurred in temporal association with administration of the hexavalent vaccine (from 1 to 7 days). In none of these victims congenital developmental alterations of the main nervous structures regulating the vital functions were observed. Only the hypoplasia of the arcuate nucleus was present in 5 cases. In one case in particular an acquired hyperacute encephalitis of the tractus solitarii nucleus was diagnosed in the brainstem. This study does not prove a causal relationship between the hexavalent vaccination and SIDS. However, we hypothesize that vaccine components could have a direct role in sparking off a lethal outcome in vulnerable babies. In conclusion, we sustain the need that deaths occurring in a short space of time after hexavalent vaccination are appropriately investigated and submitted to a post-mortem examination particularly of the autonomic nervous system by an expert pathologist to objectively evaluate the possible causative role of the vaccine in SIDS.

  4. Phenotype-driven molecular autopsy for sudden cardiac death.

    Science.gov (United States)

    Cann, F; Corbett, M; O'Sullivan, D; Tennant, S; Hailey, H; Grieve, J H K; Broadhurst, P; Rankin, R; Dean, J C S

    2017-01-01

    A phenotype-driven approach to molecular autopsy based in a multidisciplinary team comprising clinical and laboratory genetics, forensic medicine and cardiology is described. Over a 13 year period, molecular autopsy was undertaken in 96 sudden cardiac death cases. A total of 46 cases aged 1-40 years had normal hearts and suspected arrhythmic death. Seven (15%) had likely pathogenic variants in ion channelopathy genes [KCNQ1 (1), KCNH2 (4), SCN5A (1), RyR2(1)]. Fifty cases aged between 2 and 67 had a cardiomyopathy. Twenty-five had arrhythmogenic right ventricular cardiomyopathy (ARVC), 10 dilated cardiomyopathy (DCM) and 15 hypertrophic cardiomyopathy (HCM). Likely pathogenic variants were found in three ARVC cases (12%) in PKP2, DSC2 or DSP, two DCM cases (20%) in MYH7, and four HCM cases (27%) in MYBPC3 (3) or MYH7 (1). Uptake of cascade screening in relatives was higher when a molecular diagnosis was made at autopsy. In three families, variants previously published as pathogenic were detected, but clinical investigation revealed no abnormalities in carrier relatives. With a conservative approach to defining pathogenicity of sequence variants incorporating family phenotype information and population genomic data, a molecular diagnosis was made in 15% of sudden arrhythmic deaths and 18% of cardiomyopathy deaths. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Sudden cardiac death during first-time jogging.

    Science.gov (United States)

    Kurata, Hiromitsu; Ishigami, Akiko; Tokunaga, Itsuo; Nagasaki, Yasushi; Nishimura, Akiyoshi

    2017-01-01

    With increased interest in fitness and health care, jogging has become more popular as an exercise to promote health. However, sudden cardiac death during sports or exercise has also been reported. Some apparently healthy elderly individuals take up sports for both recreation and health improvement based only on completion of a questionnaire, without undergoing medical evaluation. We report the case of a 66-year-old Japanese man who suddenly died of acute ischemic heart disease during first-time jogging. He collapsed an hour after starting. A trainer promptly started cardiopulmonary resuscitation. An automated external defibrillator (AED) was applied, and defibrillation was attempted once by bystanders. However, he remained in cardiopulmonary arrest until he reached the emergency department, where he was pronounced dead. The autopsy found concentric hypertrophy of the left ventricular wall without fibrosis or degeneration, atherosclerotic changes in the coronary arteries, and severe lung congestion. We diagnosed death from acute myocardial ischemia. We suspect that many healthy elderly individuals have provoked a heart attack by prematurely attempting moderate or vigorous exercise, as in this case. The elderly require comprehensive medical assessment before exercise can be started. Moreover, this case shows that an AED is not always helpful. J. Med. Invest. 64: 184-186, February, 2017.

  6. Sudden increase in Antarctic sea ice: Fact or artifact?

    Science.gov (United States)

    Screen, J. A.

    2011-07-01

    Three sea ice data sets commonly used for climate research display a large and abrupt increase in Antarctic sea ice area (SIA) in recent years. This unprecedented change of SIA is diagnosed to be primarily caused by an apparent sudden increase in sea ice concentrations within the ice pack, especially in the area of the most-concentrated ice (greater than 95% concentration). A series of alternative satellite-derived records do not display any abnormal sudden SIA changes, but do reveal substantial discrepancies between different satellite sensors and sea ice algorithms. Sea ice concentrations in the central ice pack and SIA values derived from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSRE) are consistently greater than those derived from the Special Sensor Microwave Imager (SSMI). A switch in source data from the SSMI to AMSRE in mid-2009 explains most of the SIA increase in all three affected data sets. If uncorrected for, the discontinuity artificially exaggerates the winter Antarctic SIA increase (1979-2010) by more than a factor of 2 and the spring trend by almost a factor of 4. The discontinuity has a weaker influence on the summer and autumn SIA trends, on calculations of Antarctic sea ice extent, and in the Arctic.

  7. Adjunctive hyperbaric oxygen treatment for idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Chin, Chun-Shih; Lee, Tsai-Yun; Wu, Ming-Feng

    2017-01-01

    This study aims to evaluate the hearing gain efficacy from adjunctive hyperbaric oxygen (HBO₂) treatment in patients with idiopathic sudden sensorineural hearing loss (ISSHL). A retrospective analysis of chart reviews was performed on patients with ISSHL between January 2013 through December 2015. All patients were referred to us from our ENT Department for adjunctive hyperbaric oxygen treatment. The results were assessed through pure-tone audiometry (PTA) data change (hearing gain), both before and after HBO₂) treatment. Age, gender, affected ear side, HBO₂) treatment sessions, both before and after HBO₂ treatment PTA were all recorded. Ninety-three (93) patients with ISSHL were included in the study. The average hearing gain in this study was 17.9 dB (p=0.001), where a total of 46 (49.46%) patients showed an improvement (hearing gain≥dB) in response to HBO₂ treatment (p=0.002). Patients with the poorest initial severity of hearing loss who displayed a greater degree of hearing improvement after HBO₂ treatment were male and in the 40- to 59-year-old age group. This study found that adjunctive hyperbaric oxygen treatment was efficacious for patients with idiopathic sudden sensorineural hearing loss. The total average hearing gain was recorded to be 17.9 dB.

  8. 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.

  9. 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.

  10. 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

    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....... Experimental data (e.g., short-term batch respiration experiments under aerobic or anoxic conditions) collected for the calibration of the dynamic models (ASMs) often exhibit a transient phenomenon while attaining maximum activity, which cannot be explained by the current understanding of the activated sludge...... 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...

  11. 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.

  12. 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.

  13. Bilateral sudden sensorineural hearing loss as a first symptom of infective endocarditis: two case reports.

    Science.gov (United States)

    Chroni, M; Prappa, E; Kokkevi, I

    2018-02-21

    Septic emboli are an unusual cause of sudden sensorineural hearing loss, for which few reports exist in the literature. This paper presents two cases of sudden sensorineural hearing loss, initially considered as idiopathic, but which were caused by septic emboli. Hearing loss in these cases was bilateral, sequential and total. The first patient had mild fever one week prior to their presentation with sudden sensorineural hearing loss; the other patient had no additional symptoms at presentation. These patients were later diagnosed with infective endocarditis, at two and seven months following the sudden sensorineural hearing loss respectively, showing that septic emboli had been the cause of sudden sensorineural hearing loss. Septic emboli should be considered as a possible cause of sudden sensorineural hearing loss in cases of total hearing loss. This form of hearing loss should prompt the otolaryngologist to further investigate for infective endocarditis.

  14. 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...

  15. Genetic testing to predict sudden cardiac death: current perspectives and future goals

    OpenAIRE

    Priori, Silvia G.

    2014-01-01

    It is known that monogenic traits may predispose young and otherwise healthy individuals to die suddenly. Diseases such as Long QT Syndrome, Brugada Syndrome and Arrhythmogenic Right Ventricular Cardiomyopathy are well known causes of arrhythmic death in young individuals. For several years the concept of “genetic predisposition” to sudden cardiac death has been limited to these uncommon diseases. In the last few years clinical data have supported the view that risk of dying suddenly may clus...

  16. 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

  17. 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.

  18. Simultaneous idiopathic bilateral sudden hearing loss - characteristics and response to treatment

    Directory of Open Access Journals (Sweden)

    Ferit Akil

    Full Text Available Abstract Introduction 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. Objective The objective of this study is identify the characteristics and treatment response of simultaneous bilateral sudden hearing loss. Methods 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. Results 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 (p < 0.001. Immune response markers were more prevalent in bilateral sudden hearing loss. Pre-treatment audiologic thresholds were 69.1 dB for unilateral sudden hearing loss and 63.3 dB for the left ears and 67.6 dB for the right ears for bilateral sudden hearing loss without significant difference. Post-treatment average hearing threshold in unilateral sudden hearing loss was 47.0 dB and 55.4 dB 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 (p < 0.001 in spite of it was not significant in bilateral sudden hearing loss group for both ears. Between the groups; there was a significant difference for hearing improvement favouring unilateral sudden hearing loss (p < 0.001. Tinnitus scores decreased significantly in both groups of patients (p < 0.001 in spite of there was no significant difference between the

  19. Thrombus composition in sudden cardiac death from acute myocardial infarction.

    Science.gov (United States)

    Silvain, Johanne; Collet, Jean-Philippe; Guedeney, Paul; Varenne, Olivier; Nagaswami, Chandrasekaran; Maupain, Carole; Empana, Jean-Philippe; Boulanger, Chantal; Tafflet, Muriel; Manzo-Silberman, Stephane; Kerneis, Mathieu; Brugier, Delphine; Vignolles, Nicolas; Weisel, John W; Jouven, Xavier; Montalescot, Gilles; Spaulding, Christian

    2017-04-01

    It was hypothesized that the pattern of coronary occlusion (thrombus composition) might contribute to the onset of ventricular arrhythmia and sudden cardiac death (SCD) in myocardial infarction (MI). The TIDE (Thrombus and Inflammation in sudden DEath) study included patients with angiographically-proven acute coronary occlusion as the cause of a ST elevation MI (STEMI) complicated by Sudden Cardiac Death (SCD group) or not (STEMI group). Thrombi were obtained by thrombo-aspiration before primary percutaneous coronary stenting and analyzed with a quantitative method using scanning electron microscopy. We compared the composition of the thrombi responsible for the coronary occlusion between the two groups and evaluated factors influencing its composition. We included 121 patients and found that thrombus composition was not different between the SCD group (n=23) and the STEMI group (n=98) regarding content of fibrin fibers (60.3±18.4% vs. 62.4±18.4% respectively, p=0.68), platelets (16.3±19.2% vs. 15.616.7±%, p=0.76), erythrocytes (14.6±12.5% vs. 13±12.1%, p=0.73) and leukocytes (0.6±0.9% vs. 0.8±1.5%, p=0.93). Thrombus composition did not differ between patients receiving upstream-use of glycoprotein IIb/IIIa platelet receptor inhibitors (GPI) and patients free of GPI. The only factor found to influence thrombus composition was the ischemic time from symptom onset to primary PCI, with a decreased content in fibrin fibers (57.8±18.5% vs. 71.9±10.1%, p=0.0008) and a higher platelet content (19.2±19.1% vs. 7.9±5.7% p=0.014) in early presenters (6h of ischemic time). Composition of intracoronary thrombi in STEMI patients does not differ between those presenting with and without SCD. Time from symptom onset to coronary reperfusion seems to be the strongest factor influencing thrombus composition in MI. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. [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.

  1. Programme PROPANA: A model of the propagation of water leaks into sodium in steam generators

    International Nuclear Information System (INIS)

    Maupre, J.P.; McCrindle, K.B.

    1990-01-01

    The programme PROPANA presented in this paper is a two dimensional programme which models the propagation of water leaks in the Steam Generators of Sodium Cooled Reactors. It models the phenomena of self-evolution of leaks and the erosion and corrosion of target tubes by ''wastage'' leading to the creation of secondary defects. It includes models of leak detection and SGU depressurization. It is able to calculate the damage ia a SGU tube bundle up to the end of the depressurization for different leak scenario. In its current form it does not model the failure of tubes due to overheating which is the object of the programme MECTUB. Future developments of PROPANA include the addition of MECTUB to allow the combined effects of wastage and overheating to be modelled. 16 refs, 8 figs

  2. 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.

  3. 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.

  4. SUDDEN NATURAL DEATHS IN MEDICOLEGAL CASES- AN AUTOPSY BASED STUDY

    Directory of Open Access Journals (Sweden)

    C. S. Sreedevi

    2017-01-01

    Full Text Available BACKGROUND Death occurring in apparently healthy individual in a case of natural death may arise suspicion of foul play. In these circumstances these cases may be subjected to medicolegal autopsy. The disease condition may be unknown to the individual and the relatives. This study was done to review the exact cause of death in sudden unexpected deaths, and enabling or assisting the legal authorities in detection of crime, to prove or disprove the foul play. Body mass index is the most frequently used indicator of body fatness. An attempt is made to find out whether there is any significant relationship between BMI and the risk for sudden cardiac death. MATERIALS AND METHODS Data of 50 cases of sudden unexpected death brought for medicolegal autopsy at govt. T.D. medical college Alappuzha in the year 2010 were studied and information were collected from the postmortem records. Data was entered in the proforma. The histopathological examination findings of relevant cases were studied. Analysis was done using MS EXCEL and Chi-square test was used as the test of significance in the comparison between two categorical variables. RESULTS In 50 cases, male predominance was observed and 88% were males in which 50% of males died of atherosclerotic occlusive coronary artery disease and among females 33% died of myocardial infarction. While considering the systemic distribution of cause of death, the cardiovascular system was found to be most commonly affected, 33 cases (66% followed by respiratory system 7 cases (14%. In 4 (8% cases gastrointestinal system was affected. In Two cases (4% central nervous system was affected and others were generalized infection, which constituted 2 cases. Out of 33 cases observed in cardiovascular system the commonest cause being the atherosclerotic occlusive coronary artery diseases involving 27 cases (81.81% in which the predominant involvement was seen in left anterior descending artery 21 cases (77.77% followed by right

  5. Importance of early referral in sudden loss of hearing.

    Science.gov (United States)

    Rassin, Michal; Gorlansky, Nicka; Shahin, Eddie; Hacham, Yael; Grant, Pnina; Berger, Miri; Silner, Dina

    To examine the personal and clinical characteristics of patients suffering from sudden hearing loss. The participants were 45 Israeli patients, and the data was collected retrospectively from their medical files. In most cases the injury was sensory, and in one ear. The common symptom was tinnitus, followed by vertigo. In 20 per cent of the cases no preliminary signs were documented. As many as 60 per cent of the participants suffered from high levels of cholesterol. This finding might indicate a link between the events of hearing loss and patients' vascular background. A total of 42 per cent of the participants delayed their appeal to treatment, despite the appearance of symptoms. A significant link was found between quick referral to treatment and recovery. The nurse holds a central role in identifying this group of patients and ensuring their referral to further treatment.

  6. 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.

  7. Sudden Cardiac Death During Sports Activities in the General Population.

    Science.gov (United States)

    Narayanan, Kumar; Bougouin, Wulfran; Sharifzadehgan, Ardalan; Waldmann, Victor; Karam, Nicole; Marijon, Eloi; Jouven, Xavier

    2017-12-01

    Regular exercise reduces cardiovascular and overall mortality. Participation in sports is an important determinant of cardiovascular health and fitness. Regular sports activity is associated with a smaller risk of sudden cardiac death (SCD). However, there is a small risk of sports-related SCD. Sports-related SCD accounts for approximately 5% of total SCD. SCD among athletes comprises only a fraction of all sports-related SCD. Sport-related SCD has a male predominance and an average age of affliction of 45 to 50 years. Survival is better than for other SCD. This review summarizes links between sports and SCD and discusses current knowledge and controversies. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. 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.

  9. Surprises in the suddenly-expanded infinite well

    International Nuclear Information System (INIS)

    Aslangul, Claude

    2008-01-01

    I study the time evolution of a particle prepared in the ground state of an infinite well after the latter is suddenly expanded. It turns out that the probability density |Ψ(x, t)| 2 shows up quite a surprising behaviour: for definite times, plateaux appear for which |Ψ(x, t)| 2 is constant on finite intervals for x. Elements of theoretical explanation are given by analysing the singular component of the second derivative ∂ xx Ψ(x, t). Analytical closed expressions are obtained for some specific times, which easily allow us to show that, at these times, the density organizes itself into regular patterns provided the size of the box is large enough; more, above some critical size depending on the specific time, the density patterns are independent of the expansion parameter. It is seen how the density at these times simply results from a construction game with definite rules acting on the pieces of the initial density

  10. 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.

  11. A survival analysis of sudden current account correction for Costa Rica

    Directory of Open Access Journals (Sweden)

    Jorge León Murillo

    2016-12-01

    Full Text Available Using a survival model approach using data panel, an exploratory analysis is made to estimate the probability of a sudden current account correction in Costa Rica. The results show that the estimated probability of a current account reversal decreases when: i the five years ahead real-growth increases, ii the external situation of similar countries improves, iii the economic dependency ratio increases, iv the world’s GDP percentage for which the country have signed a trade agreement increases, v reserves accumulation accelerates and vi the institutional framework becomes more democratic. On the other hand, an increase in the total factor productivity (TFP growth 5-year ahead raises likelihood of a reversal. The effect of capital controls on the probability showed an ambiguous behavior. Annual data from 1981 to 2012 for 116 countries is used.

  12. 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.

  13. Sudden gains in exposure-focused cognitive-behavioral group therapy for panic disorder.

    Science.gov (United States)

    Nogueira-Arjona, Raquel; Santacana, Martí; Montoro, María; Rosado, Silvia; Guillamat, Roser; Vallès, Vicenç; Fullana, Miquel A

    2017-11-01

    In the context of psychological treatment, a sudden gain is a large and enduring improvement in symptom severity that occurs between two single therapy sessions. The influence of sudden gains on long-term outcomes and functional impairment in anxiety disorders is not well understood, and little is known with regard to panic disorder in particular. In addition, previous research on patients with anxiety disorders has produced inconsistent results regarding the relationship between sudden gains and cognitive change. We examined the incidence of sudden gains in a large sample (n = 116) of panic disorder patients undergoing exposure-focused cognitive-behavioral group therapy, and compared panic severity, functional impairment, and cognitive change in patients with and without sudden gains at posttreatment and 6-month follow-up. Participants who experienced sudden gains displayed lower levels of panic severity and functional impairment at posttreatment and 6-month follow-up than those who did not experience sudden gains. However, we observed no difference in cognitive changes between groups, either at posttreatment or at follow-up. Our results demonstrate that the beneficial effects of sudden gains on therapeutic outcomes not only extend to long-term and functional outcome measures but are also evident in less cognitive (i.e., exposure-focused) forms of psychological treatment. Sudden gains are common in panic disorder patients undergoing exposure-based cognitive-behavioral group therapy. Sudden gains during exposure-focused therapy are linked to greater improvement in panic disorder severity and functional impairment. The positive impact of sudden gains on panic disorder severity and functional impairment is maintained in the long term. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Sudden unexpected death in children with a previously diagnosed cardiovascular disorder

    NARCIS (Netherlands)

    Polderman, Florens N.; Cohen, Joeri; Blom, Nico A.; Delhaas, Tammo; Helbing, Wim A.; Lam, Jan; Sobotka-Plojhar, Marta A.; Temmerman, Arno M.; Sreeram, Narayanswani

    2004-01-01

    BACKGROUND: It is known that children with previously diagnosed heart defects die suddenly. The causes of death are often unknown. OBJECTIVE: The aim of the study was to identify all infants and children within the Netherlands with previously diagnosed heart disease who had a sudden unexpected death

  15. Sudden unexpected death in children with a previously diagnosed cardiovascular disorder

    NARCIS (Netherlands)

    Polderman, F.N.; Cohen, Joeri; Blom, N.A.; Delhaas, T.; Helbing, W.A.; Lam, J.; Sobotka-Plojhar, M.A.; Temmerman, Arno M.; Sreeram, N.

    2004-01-01

    Background: It is known that children with previously diagnosed heart defects die suddenly. The causes of death are often unknown. Objective: The aim of the study was to identify all infants and children within the Netherlands with previously diagnosed heart disease who had a sudden unexpected death

  16. 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)....

  17. 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

    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 Austral...

  18. Sudden oak death and Phytophthora ramorum: a summary of the literature

    Science.gov (United States)

    John T. Kliejunas

    2010-01-01

    Sudden oak death and Phytophthora ramorum, both first recognized about a decade ago, have been the subject of hundreds of scientific and popular press articles. This document presents a comprehensive, concise summary of sudden oak death and P. ramorum research findings and management activities. Topics covered include...

  19. A 23-year review of sudden natural death autopsies in the Niger ...

    African Journals Online (AJOL)

    Background: Death occurring suddenly especially when the victim was active and recently fit, call for attention and thorough investigation to rule out secret homicide. Aim: To study the pattern of sudden natural death in the Niger Delta region of Nigeria. Methodology: The coroner's autopsy reports and hospital autopsy ...

  20. Utility of Post-Mortem Genetic Testing in Cases of Sudden Arrhythmic Death Syndrome

    NARCIS (Netherlands)

    Lahrouchi, Najim; Raju, Hariharan; Lodder, Elisabeth M.; Papatheodorou, Efstathios; Ware, James S.; Papadakis, Michael; Tadros, Rafik; Cole, Della; Skinner, Jonathan R.; Crawford, Jackie; Love, Donald R.; Pua, Chee J.; Soh, Bee Y.; Bhalshankar, Jaydutt D.; Govind, Risha; Tfelt-Hansen, Jacob; Winkel, Bo G.; van der Werf, Christian; Wijeyeratne, Yanushi D.; Mellor, Greg; Till, Jan; Cohen, Marta C.; Tome-Esteban, Maria; Sharma, Sanjay; Wilde, Arthur A. M.; Cook, Stuart A.; Bezzina, Connie R.; Sheppard, Mary N.; Behr, Elijah R.

    2017-01-01

    Sudden arrhythmic death syndrome (SADS) describes a sudden death with negative autopsy and toxicological analysis. Cardiac genetic disease is a likely etiology. This study investigated the clinical utility and combined yield of post-mortem genetic testing (molecular autopsy) in cases of SADS and

  1. [Prevention of sudden death during sport activity in view of new recommendations].

    Science.gov (United States)

    Sovová, E

    2013-05-01

    The study deals with the prevention of sudden death in sportsmen. It analyzes the influence of ECG examination on reducing the risk of sudden death. It presents new recommendations for ECG assessment in sportsmen and a new algorithm for examination of middle- aged and senior subjects.

  2. Sudden infant death syndrome in mice with an inherited mutation in RyR2

    NARCIS (Netherlands)

    Mathur, Nitin; Sood, Subeena; Wang, Sufen; van Oort, Ralph J.; Sarma, Satyam; Li, Na; Skapura, Darlene G.; Bayle, J. Henri; Valderrábano, Miguel; Wehrens, Xander H. T.

    2009-01-01

    BACKGROUND: Mutations in the cardiac ryanodine receptor gene (RyR2) have been recently identified in victims of sudden infant death syndrome. The aim of this study was to determine whether a gain-of-function mutation in RyR2 increases the propensity to cardiac arrhythmias and sudden death in young

  3. The OakMapper WebGIS: improved access to sudden oak death spatial data

    Science.gov (United States)

    K. Tuxen; M. Kelly

    2008-01-01

    Access to timely and accurate sudden oak death (SOD) location data is critical for SOD monitoring, management and research. Several websites (hereafter called the OakMapper sites) associated with sudden oak death monitoring efforts have been maintained with up-todate SOD location information for over five years, providing information and maps of the most current...

  4. Next-Generation Sequencing in Post-mortem Genetic Testing of Young Sudden Cardiac Death Cases

    NARCIS (Netherlands)

    Lahrouchi, Najim; Behr, Elijah R.; Bezzina, Connie R.

    2016-01-01

    Sudden cardiac death (SCD) in the young ( <40 years) occurs in the setting of a variety of rare inherited cardiac disorders and is a disastrous event for family members. Establishing the cause of SCD is important as it permits the pre-symptomatic identification of relatives at risk of SCD. Sudden

  5. The yield of family screening in sudden unexplained death in the young

    NARCIS (Netherlands)

    Van De Werf, C.; Hofman, N.; Tan, H.L.; Van Langen, I.M.; Wilde, A.A.M.

    2009-01-01

    Objectives: When autopsy is performed after sudden death of a young person, cause of death remains undetermined in 6-65%, which is termed sudden unexplained death (SUD). In these cases molecular autopsy and cardiological and genetic examination in surviving first degree relatives is known to unmask

  6. 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 ...

  7. The Metabolic Syndrome and Risk of Sudden Cardiac Death: The Atherosclerosis Risk in Communities Study.

    Science.gov (United States)

    Hess, Paul L; Al-Khalidi, Hussein R; Friedman, Daniel J; Mulder, Hillary; Kucharska-Newton, Anna; Rosamond, Wayne R; Lopes, Renato D; Gersh, Bernard J; Mark, Daniel B; Curtis, Lesley H; Post, Wendy S; Prineas, Ronald J; Sotoodehnia, Nona; Al-Khatib, Sana M

    2017-08-23

    Prior studies have demonstrated a link between the metabolic syndrome and increased risk of cardiovascular mortality. Whether the metabolic syndrome is associated with sudden cardiac death is uncertain. We characterized the relationship between sudden cardiac death and metabolic syndrome status among participants of the ARIC (Atherosclerosis Risk in Communities) Study (1987-2012) free of prevalent coronary heart disease or heart failure. Among 13 168 participants, 357 (2.7%) sudden cardiac deaths occurred during a median follow-up of 23.6 years. Participants with the metabolic syndrome (n=4444) had a higher cumulative incidence of sudden cardiac death than those without it (n=8724) (4.1% versus 2.3%, P metabolic syndrome, the metabolic syndrome was independently associated with sudden cardiac death (hazard ratio, 1.70, 95% confidence interval, 1.37-2.12, P metabolic syndrome criteria components. The risk of sudden cardiac death varied according to the number of metabolic syndrome components (hazard ratio 1.31 per additional component of the metabolic syndrome, 95% confidence interval, 1.19-1.44, P metabolic syndrome was associated with a significantly increased risk of sudden cardiac death irrespective of sex or race. The risk of sudden cardiac death was proportional to the number of metabolic syndrome components. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  8. Identification of evidence for autoimmune pathology of bilateral sudden sensorineural hearing loss using proteomic analysis.

    Science.gov (United States)

    Lee, Jeon Mi; Kim, Jin Young; Bok, Jinwoong; Kim, Kyu-Sung; Choi, Jae Young; Kim, Sung Huhn

    2017-10-01

    Sudden sensorineural hearing loss (S-SNHL) is an inner ear disorder with an abrupt hearing loss occurring sudden sensorineural hearing loss; LC-MS: liquid chromatography-mass spectrometry; MS: mass spectrometry; autoAb: autoantibody; 1-DE: one-dimensional electrophoresis. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. 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....

  10. Sudden infant death syndrome (SIDS) or cot death: A review | Ogbu ...

    African Journals Online (AJOL)

    Sudden death of an infant is not an uncommon event and when there is no adequate cause to explain the death it poses a diagnostic dilemma for the clinician, and makes discussion of the cause of death with parents quite difficult and unsatisfactory. Sudden infant death syndrome (SIDS) or cot death is a diagnostic entity ...

  11. Survival and sudden cardiac death after septal ablation for hypertrophic obstructive cardiomyopathy

    DEFF Research Database (Denmark)

    Jensen, Morten Kvistholm; Havndrup, Ole; Hassager, Christian

    2011-01-01

    Reports of long-term survival and the risk of sudden cardiac death (SCD) after percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM) are sparse.......Reports of long-term survival and the risk of sudden cardiac death (SCD) after percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM) are sparse....

  12. Utility of Post-Mortem Genetic Testing in Cases of Sudden Arrhythmic Death Syndrome

    DEFF Research Database (Denmark)

    Lahrouchi, Najim; Raju, Hariharan; Lodder, Elisabeth M

    2017-01-01

    BACKGROUND: Sudden arrhythmic death syndrome (SADS) describes a sudden death with negative autopsy and toxicological analysis. Cardiac genetic disease is a likely etiology. OBJECTIVES: This study investigated the clinical utility and combined yield of post-mortem genetic testing (molecular autopsy...

  13. 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,

  14. The molecular autopsy: an indispensable step following sudden cardiac death in the young?

    Science.gov (United States)

    Boczek, Nicole J.; Tester, David J.; Ackerman, Michael J.

    2013-01-01

    Annually thousands of sudden deaths involving young individuals (autopsy. In fact, epidemiological studies have estimated that over half of sudden deaths involving previously healthy young individuals have no morphological abnormalities identifiable at autopsy. Cardiac channelopathies associated with structurally normal hearts such as long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and Brugada syndrome (BrS), leave no evidence to be found at autopsy, leaving investigators to only speculate that a lethal arrhythmia might lie at the heart of a sudden unexplained death (SUD). In cases of autopsy-negative SUD, continued investigation, through the use of a cardiological and genetic evaluation of first- or second-degree relatives and/or a molecular autopsy, may pinpoint the underlying mechanism attributing to the sudden death and allow for the identification of living family members with the pathogenic substrate that renders them vulnerable to an increased risk for cardiac events, including sudden death. PMID:22993115

  15. Non-functioning posterior communicating arteries of circle of Willis in idiopathic sudden hearing loss.

    Science.gov (United States)

    De Felice, C; De Capua, B; Tassi, R; Mencattini, G; Passàli, D

    2000-10-07

    Most cases of sudden hearing loss have no identifiable cause. A link between compensatory blood flow through the circle of Willis and recovery from sudden hearing loss has, however, been suggested. We assessed 22 patients with sudden hearing loss who had no cerebrovascular disease, and 41 controls matched for age and sex. We took ultrasonographic doppler flow measurements of the extracranial carotid and vertebrobasilar systems and independent audiological measurements. 12 patients with sudden hearing loss, compared with four controls had bilateral non-functioning posterior communicating arteries (p=0.00019). Our findings suggest a strong association between a non-functioning posterior communicating artery of the circle of Willis and sudden hearing loss.

  16. 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.

  17. 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...

  18. Genetic testing to predict sudden cardiac death: current perspectives and future goals

    Directory of Open Access Journals (Sweden)

    Silvia G. Priori

    2014-01-01

    Full Text Available It is known that monogenic traits may predispose young and otherwise healthy individuals to die suddenly. Diseases such as Long QT Syndrome, Brugada Syndrome and Arrhythmogenic Right Ventricular Cardiomyopathy are well known causes of arrhythmic death in young individuals. For several years the concept of “genetic predisposition” to sudden cardiac death has been limited to these uncommon diseases. In the last few years clinical data have supported the view that risk of dying suddenly may cluster in families, supporting the hypothesis of a genetic component for sudden cardiac death. In this review I will try to provide an overview of current knowledge about genetics of sudden death. I will approach this topic by discussing first where we stand in the use of genetics for risk stratification and therapy selection in monogenic diseases and I will then move to discuss the contribution of genetics to patient profiling in acquired cardiovascular diseases.

  19. 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

    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....... 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...

  20. 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 (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.

  1. Predictors of sudden cardiac death in atrial fibrillation: The Atherosclerosis Risk in Communities (ARIC study.

    Directory of Open Access Journals (Sweden)

    Ryan J Koene

    Full Text Available We previously reported that incident atrial fibrillation (AF is associated with an increased risk of sudden cardiac death (SCD in the general population. We now aimed to identify predictors of SCD in persons with AF from the Atherosclerosis Risk in Communities (ARIC study, a community-based cohort study. We included all participants who attended visit 1 (1987-89 and had no prior AF (n = 14,836. Incident AF was identified from study electrocardiograms and hospitalization discharge codes through 2012. SCD was physician-adjudicated. We used cause-specific Cox proportional hazards models, followed by stepwise selection (backwards elimination, removing all variables with p>0.10 to identify predictors of SCD in participants with AF. AF occurred in 2321 (15.6% participants (age 45-64 years, 58% male, 18% black. Over a median of 3.3 years, SCD occurred in 110 of those with AF (4.7%. Predictors of SCD in AF included higher age, body mass index (BMI, coronary heart disease, hypertension, diabetes, current smoker, left ventricular hypertrophy, increased heart rate, and decreased albumin. Predictors associated only with SCD and not other cardiovascular (CV death included increased BMI (HR per 5-unit increase, 1.15, 95% CI, 0.97-1.36, p = 0.10, increased heart rate (HR per SD increase, 1.18, 95% CI 0.99-1.41, p = 0.07, and low albumin (HR per SD decrease 1.23, 95% CI 1.02-1.48, p = 0.03. In the ARIC study, predictors of SCD in AF that are not associated with non-sudden CV death included increased BMI, increased heart rate, and low albumin. Further research to confirm these findings in larger community-based cohorts and to elucidate the underlying mechanisms to facilitate prevention is warranted.

  2. Sudden death in the first 2 years of life following immunization in the Republic of Korea.

    Science.gov (United States)

    Choe, Young June; Kim, Jong-Hee; Son, Hyun Jin; Bae, Geun-Ryang; Lee, Duk-hyoung

    2012-12-01

    Because the peak age for incidence of sudden deaths in infancy temporally coincides with the age of infant primary immunization, some have raised the question as to whether immunization is a risk factor for sudden death in infancy. Recent occurrence of two sudden deaths in infants in Korea has renewed concerns about the causal association between immunization and sudden deaths in infants. We carried out a retrospective review of data from the Korea Centers for Disease Control and Prevention Adverse Events Following Immunization Surveillance System and Vaccine Compensation programs. From 1994 to 2011, a total of 45 cases of sudden deaths in the first 2 years of life following immunization were reported in Korea. The causes of death were classified as follows: infectious diseases (n= 13); accidental injuries (n= 7); congenital abnormalities (n= 2); and malignancy (n= 1). Of 20 sudden deaths in infancy, nine deaths met Brighton Collaboration case definition level I and II, and therefore were classified as possible sudden infant death syndrome cases. Hepatitis B vaccine (n= 13) was the most frequent vaccine with temporal association with sudden deaths in the first 2 years of life. Few sudden deaths in the first 2 years of life following immunization have been reported, despite the use of universal immunization in Korea. The majority of deaths in infancy did not meet case definition for sudden infant death syndrome. Encouraging investigators to perform thorough investigation, including postmortem autopsy and death scene examination, may promote data comparability and provide guidance on decision-making in the vaccine-safety monitoring and response system in Korea. © 2012 The Authors. Pediatrics International © 2012 Japan Pediatric Society.

  3. Sudden death after pediatric heart transplantation: analysis of data from the Pediatric Heart Transplant Study Group.

    Science.gov (United States)

    Daly, Kevin P; Chakravarti, Sujata B; Tresler, Margaret; Naftel, David C; Blume, Elizabeth D; Dipchand, Anne I; Almond, Christopher S

    2011-12-01

    Sudden death is a well-recognized complication of heart transplantation. Little is known about the incidence and risk factors for sudden death after transplant in children. The purpose of this study was to determine the incidence of and risk factors for sudden death. This retrospective multicenter cohort study used the Pediatric Heart Transplant Study Group (PHTS) database, an event-driven registry of children aged heart transplantation between 1993 and 2007. Standard Kaplan-Meier and parametric analyses were used for survival analysis. Multivariate analysis in the hazard-function domain was used to identify risk factors for sudden death after transplant. Of 604 deaths in 2,491 children who underwent heart transplantation, 94 (16%) were classified as sudden. Freedom from sudden death was 97% at 5 years, and the hazard for sudden death remained constant over time at 0.01 deaths/year. Multivariate risk factors associated with sudden death included black race (hazard ratio [HR], 2.6; p transplant (HR, 1.8; p = 0.008), older age (HR, 1.4/10 years of age; p = 0.03), and an increased number of rejection episodes in the first post-transplant year (HR, 1.6/episode; p = 0.03). Sudden death accounts for 1 in 6 deaths after heart transplant in children. Older recipient age, recurrent rejection within the first year, black race, and UNOS status 2 at listing were associated with sudden death. Patients with 1 or more of these risk factors may benefit from primary prevention efforts. Copyright © 2011 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  4. 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

    2016-10-18

    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. 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. 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. 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 heart rate was not associated with sudden death. © 2016 Canadian Medical

  5. 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

  6. 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

  7. Cardiac muscarinic receptor overexpression in sudden infant death syndrome.

    Directory of Open Access Journals (Sweden)

    Angelo Livolsi

    Full Text Available BACKGROUND: Sudden infant death syndrome (SIDS remains the leading cause of death among infants less than 1 year of age. Disturbed expression of some neurotransmitters and their receptors has been shown in the central nervous system of SIDS victims but no biological abnormality of the peripheral vago-cardiac system has been demonstrated to date. The present study aimed to seek vago-cardiac abnormalities in SIDS victims. The cardiac level of expression of muscarinic receptors, as well as acetylcholinesterase enzyme activity were investigated. METHODOLOGY/PRINCIPAL FINDINGS: Left ventricular samples and blood samples were obtained from autopsies of SIDS and children deceased from non cardiac causes. Binding experiments performed with [(3H]NMS, a selective muscarinic ligand, in cardiac membrane preparations showed that the density of cardiac muscarinic receptors was increased as shown by a more than doubled B(max value in SIDS (n = 9 SIDS versus 8 controls. On average, the erythrocyte acetylcholinesterase enzyme activity was also significantly increased (n = 9 SIDS versus 11 controls. CONCLUSIONS: In the present study, it has been shown for the first time that cardiac muscarinic receptor overexpression is associated with SIDS. The increase of acetylcholinesterase enzyme activity appears as a possible regulatory mechanism.

  8. A case of sudden death after Japanese encephalitis vaccination.

    Science.gov (United States)

    Bunai, Yasuo; Ishii, Akira; Akaza, Kayoko; Nagai, Atsushi; Nishida, Naoki; Yamaguchi, Seiji

    2015-07-01

    Japanese encephalitis (JE) virus is estimated to result in 3500-50,000 clinical cases every year, with mortality rates of up to 20-50% and a high percentage of neurological sequelae in survivors. Vaccination is the single most important measure in preventing this disease. Inactivated Vero cell culture-derived JE vaccines have not been linked to any fatalities, and few serious adverse events after vaccination have been reported. Here, we report a case of sudden death in which a 10-year-old boy experienced cardiopulmonary arrest 5 min after receiving a Japanese encephalitis vaccination. He had been receiving psychotropic drugs for the treatment of pervasive developmental disorders. Postmortem examinations were nonspecific, and no signs of dermatologic or mucosal lesions or an elevation of the serum tryptase level, which are characteristic of anaphylaxis, were observed. A toxicological examination revealed that the blood concentrations of the orally administered psychotropic drugs were within the therapeutic ranges. The patient was considered to have died of an arrhythmia that was not directly associated with the vaccination. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. 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.

  10. Risk factors for sudden cardiac death among patients with schizophrenia.

    Science.gov (United States)

    Hou, Ping-Yi; Hung, Galen Chin-Lun; Jhong, Jia-Rong; Tsai, Shang-Ying; Chen, Chiao-Chicy; Kuo, Chian-Jue

    2015-10-01

    Patients with schizophrenia suffer from excessive premature mortality, and sudden cardiac death (SCD) is receiving growing attention as a potential cause. The present study investigated the incidence of SCD and its risk factors in a large schizophrenia cohort. We enrolled a consecutive series of 8264 patients diagnosed with schizophrenia (according to DSM-III-R and DSM-IV criteria) who were admitted to a psychiatric center in northern Taiwan from January 1, 1985 through December 31, 2008. By linking with national mortality database, 64 cases of SCD were identified. The standardized mortality ratio (SMR) for SCD was estimated. The cases were matched with controls randomly selected using risk-set sampling in a 1:2 ratio. A standardized chart review process was used to collect socio-demographic and clinical characteristics and the prescribed drugs for each study subject. Multivariate conditional logistic regression analysis was used to identify correlates of SCD at the index admission and the latest admission. The SMR for SCD was 4.5. For the clinical profiles at the index admission, physical disease (adjusted risk ratio [aRR]=2.91, Paggressive behaviors (aRR=3.99, Paggressive behaviors (aRR=3.26, Paggression is a crucial risk factor that deserves ongoing work for clarifying the mechanisms mediating SCD in schizophrenia. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Association between Family History and Idiopathic Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Binnetoğlu, Adem; Yumuşakhuylu, Ali Cemal; Demir, Berat; Bağlam, Tekin; Derinsu, Ufuk; Sarı, Murat

    2015-04-01

    Sudden sensorineural hearing loss (SSNHL) is defined as hearing loss of at least 30 dB occurring within three days over at least three contiguous frequencies. The etiology of SSNHL cannot always be precisely determined; in such cases, this condition is termed idiopathic SSNHL (ISSNHL). This unique study investigates the relationship between ISSNHL and positive family history for ISSNHL. In total, 125 patients diagnosed with ISSNHL were retrospectively reviewed. The presence of ISSNHL in the family medical history and degree of kinship of family members diagnosed with ISSNHL were determined. For univariate analysis, a chi-squared test and/or Fisher's exact test was used for between-group comparisons of qualitative variables; a t-test was used for quantitative variables. Significant variables in the univariate analysis were introduced into stepwise logistic regression for multivariate analysis. Pfamily medical history of ISSNHL, whereas 83 (66.4%) did not. A statistically significant association between the development of ISSNHL and a family history of ISSNHL was observed (p<0.05). Our study supports an association between ISSNHL and genetic predisposition. Proving genetic susceptibility to ISSNHL will lead to improvements in the prediction, early diagnosis, and treatment of this disease.

  12. Phrenic nerves and diaphragms in sudden infant death syndrome.

    Science.gov (United States)

    Weis, J; Weber, U; Schröder, J M; Lemke, R; Althoff, H

    1998-01-30

    Disturbances of the respiratory system may be an important factor in the cascade of events leading to sudden infant death syndrome (SIDS). Even though the diaphragm is the major respiratory muscle in infants, little is known about alterations of this muscle and of the phrenic nerve in SIDS. In the present study, diaphragms and phrenic nerves of 24 SIDS infants and seven controls were analyzed. Morphometric analysis revealed only slightly larger cross sectional areas of phrenic nerve axons but no increase in myelin sheath thickness in SIDS cases. However, in one SIDS case, myelinated nerve fibre density was severely reduced. Using electron microscopy, several nerve fibres of SIDS infants showed focal accumulations of neurofilaments. Muscle fibre diameters in SIDS diaphragms were significantly larger compared to controls (P fibre ruptures and contracture bands were found. These prominent nonspecific ultrastructural alterations should advise caution in the interpretation of morphometric data. Thus, in some cases exemplified by one case of the present series, decreased density of phrenic nerve myelinated axons might contribute to SIDS. Still, the present results indicate that development of phrenic nerves and diaphragms is not delayed in most SIDS infants.

  13. Electrocardiographic features of sudden unexpected death in epilepsy.

    Science.gov (United States)

    Chyou, Janice Y; Friedman, Daniel; Cerrone, Marina; Slater, William; Guo, Yu; Taupin, Daniel; O'Rourke, Sean; Priori, Silvia G; Devinsky, Orrin

    2016-07-01

    Sudden unexpected death in epilepsy (SUDEP) is the most common cause of epilepsy-related mortality. We hypothesized that electrocardiography (ECG) features may distinguish SUDEP cases from living subjects with epilepsy. Using a matched case-control design, we compared ECG studies of 12 consecutive cases of SUDEP over 10 years and 22 epilepsy controls matched for age, sex, epilepsy type (focal, generalized, or unknown/mixed type), concomitant antiepileptic, and psychotropic drug classes. Conduction intervals and prevalence of abnormal ventricular conduction diagnosis (QRS ≥110 msec), abnormal ventricular conduction pattern (QRS <110 msec, morphology of incomplete right or left bundle branch block or intraventricular conduction delay), early repolarization, and features of inherited cardiac channelopathies were assessed. Abnormal ventricular conduction diagnosis and pattern distinguished SUDEP cases from matched controls. Abnormal ventricular conduction diagnosis was present in two cases and no controls. Abnormal ventricular conduction pattern was more common in cases than controls (58% vs. 18%, p = 0.04). Early repolarization was similarly prevalent in cases and controls, but the overall prevalence exceeded that of published community-based cohorts. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  14. Remittances as aid following major sudden-onset natural disasters.

    Science.gov (United States)

    Bragg, Catherine; Gibson, Glenn; King, Haleigh; Lefler, Ashley A; Ntoubandi, Faustin

    2018-01-01

    There is a general assumption, based on macroeconomic studies, that remittances will rise following major sudden-onset natural disasters. This is confirmed by a few assessments involving country-specific research, and usually short-term data. This study, questioning conventional wisdom, reviewed and graphed annual and quarterly remittance flows using International Monetary Fund and World Bank data from 2000-14 for 12 countries that confronted 18 major natural disasters. It found that, regardless of event type, annual remittances rose steadily from 2000-14 except for after the 2008-09 financial crisis. Post disaster, there was a quarterly increase in the majority of cases (confirming previous research) but there was seldom an annual increase in the year of the disaster greater than the average annual increase in 2000-14. It appears that remittance senders rush to provide assistance after a natural disaster, but since their own financial situation has not changed, the immediate increase is compensated by a later decrease. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

  15. 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.

  16. 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

  17. 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.

  18. Preferences of Patients for Discussing Sudden Unexpected Death in Epilepsy

    Directory of Open Access Journals (Sweden)

    Sūna Normunds

    2017-08-01

    Full Text Available People with epilepsy have increased mortality rates, which is partially attributed to sudden unexpected death in epilepsy syndrome (SUDEP. Poor seizure control appears to be the strongest SUDEP risk factor. Management of epilepsy and adherence to therapy is critical to seizure control. The belief by caregivers of negative influence caused by being informed about the syndrome is the main reason SUDEP is not disclosed. There are no clear recommendations when to disclose the risk of SUDEP and how much information should be provided. We addressed the preferences of Latvian epilepsy patients for discussing SUDEP as well as awareness of the syndrome. Our study involved 55 epilepsy patients. We found that, as in other studies, our patients were relatively well informed about SUDEP. We found that a considerable proportion of patients preferred to receive information about SUDEP from a general practitioner. We note the belief of patients that the disclosure of SUDEP would either improve or have no effect on the quality of life. We were able to identify groups of patients with a self-reported belief of more frequent expected anxiety and poor adherence to medical treatment. Our data improves the understanding of preferences of patient for discussing the negative aspects of epilepsy.

  19. 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

    with electrocardiographic documentation of VT/VF were included. Conditional logistic regression analysis was used to assess the association between SCA and OPD. Pre-specified subgroup analyses were performed regarding age, sex, cardiovascular risk-profile, disease severity, and current use of respiratory drugs. RESULTS......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......: A higher risk of SCA was observed in patients with OPD (n = 190 cases [15%], 622 controls [11%]) than in those without OPD (OR adjusted for cardiovascular risk-profile 1.4 [1.2-1.6]). In OPD patients with a high cardiovascular risk-profile (OR 3.5 [2.7-4.4]) a higher risk of SCA was observed than in those...

  20. A study on effective system depressurization during a PWR vessel bottom break LOCA with HPI failure and gas inflow prevention. ROSA-V/LSTF test SB-PV-05

    International Nuclear Information System (INIS)

    Suzuki, Mitsuhiro; Takeda, Takeshi; Asaka, Hideaki; Nakamura, Hideo

    2006-11-01

    A small break loss-of-coolant accident (SBLOCA) experiment was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study effects of accident management (AM) measures on core cooling, which are important in case of total failure of high pressure injection (HPI) system during an SBLOCA at a pressurized water reactor (PWR). The LSTF is a full-height and 1/48 volume-scaled facility simulating a 4-loop Westinghouse-type PWR (3423 MWt). The experiment, SB-PV-05, simulated a PWR vessel bottom SBLOCA with a rupture of nine instrument tubes, which is equivalent to 0.18% cold leg break. It is clarified that AM actions with steam generator (SG) depressurization to achieve a primary loop cooling rate at -55 K/h and auxiliary feedwater supply for 30 minutes are effective to avoid core uncovery by actuating the low pressure injection (LPI) system. It is also shown through the comparison with the previous experiment of SB-PV-03 that prevention of non-condensable gas inflow from the accumulator injection system (AIS) is very important to actuate the LPI to achieve adequate core cooling. This report presents experiment results of SB-PV-05 in detail and shows the effects of gas inflow prevention on core cooling through the estimation of primary coolant mass and energy balance in the primary system. (author)

  1. Evaluation of cardiovascular risks and recovery of idiopathic sudden sensorineural hearing loss in hospitalised patients: comparison between complete and partial sudden sensorineural hearing loss.

    Science.gov (United States)

    Haremza, C; Klopp-Dutote, N; Strunski, V; Page, C

    2017-10-01

    To evaluate the presence of cardiovascular risk factors and recovery of idiopathic sudden sensorineural hearing loss in hospitalised patients. A single-centre retrospective study of 80 patients hospitalised for idiopathic sudden sensorineural hearing loss was conducted over a 6-year period. Mean pure tone hearing thresholds were assessed by pure tone audiometry. Twenty-three of 80 patients (28.75 per cent) initially had no cardiovascular risk factors. Forty-five patients had hyperlipidaemia, 22 patients had hypertension, 7 patients had diabetes mellitus and 7 patients were obese. No statistically significant difference was observed between patients with complete versus partial sudden sensorineural hearing loss (p = 0.0708) concerning the cardiovascular risk factors. At long-term follow up, the hearing recovery rate was not significantly different between the two groups of patients (p = 0.7541). The lack of a clear relationship between idiopathic sudden sensorineural hearing loss and cardiovascular risk factors suggests that sudden sensorineural hearing loss has a predominantly multifactorial disease profile regardless of hearing impairment severity.

  2. Sudden gains in Cognitive Therapy and Interpersonal Psychotherapy for adult depression.

    Science.gov (United States)

    Lemmens, Lotte H J M; DeRubeis, Robert J; Arntz, Arnoud; Peeters, Frenk P M L; Huibers, Marcus J H

    2016-02-01

    We examined the rates, baseline predictors and clinical impact of sudden gains in a randomized comparison of individual Cognitive Therapy (CT) and Interpersonal Psychotherapy (IPT) for adult depression. 117 depressed outpatients received 16-20 sessions of either CT or IPT. Session-by-session symptom severity was assessed using the BDI-II. Sudden gains were examined using the original criteria as defined by Tang and DeRubeis (1999b). Furthermore, we examined whether the duration of the between-session interval at which sudden gains were recorded affected the results. There were significantly more patients with sudden gains in CT (42.2%) as compared to IPT (24.5%). The difference appeared to be driven by the criterion representing the stability of the gain. No between-group differences were found with regard to the magnitude, timing and predictors of the gains. Those with sudden gains were less depressed at post-treatment and follow-up. After controlling for the duration of the between-session interval, the difference in rates between the two conditions became a non-significant trend. Other sudden gains characteristics were similar to those observed when allowing for longer intervals as well. The current study indicates differences in occurrence of sudden gains in two treatment modalities that overall showed similar results, which might reflect different mechanisms of change. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Investigation of neutrophil-to-lymphocyte ratio and mean platelet volume in sudden hearing loss,

    Directory of Open Access Journals (Sweden)

    Rauf Oguzhan Kum

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Several theories attempt to explain the pathophysiology of sudden hearing loss. OBJECTIVE: The objective of this study was to investigate the possible role of inflammation and atherothrombosis in sudden hearing loss patients through the neutrophil-to-lymphocyte ratio and mean platelet volume. METHODS: Study design - retrospective cross-sectional historical cohort. This study was conducted on two groups: one with 59 individuals diagnosed with sudden hearing loss, and other with 59 healthy individuals with the same characteristics of gender and age distribution, neutrophil-to-lymphocyte ratio and mean platelet volume levels were measured in patients diagnosed with sudden hearing loss as well as in the control group, and it was verified whether these results interfered for a better or worse prognosis with treatment of sudden deafness. RESULTS: Neutrophil-to-lymphocyte ratio levels are much higher in patients diagnosed with sudden hearing loss compared to the control group. Similarly, mean levels of neutrophil-to-lymphocyte ratio are higher in non-recovered versus recovered patients (p = 0.001. However, we could not find a correlation with mean platelet volume levels (p > 0.05. CONCLUSION: Neutrophil-to-lymphocyte ratio is a quick and reliable indicator regarding diagnosis and prognosis of sudden hearing loss; on the other hand, mean platelet volume may be considered a less important indicator in this aspect.

  4. Canal Paresis in Benign Paroxysmal Positional Vertigo Secondary to Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Lee, Jong Bin; Choi, Seong Jun

    2015-12-01

    To review the clinical features of benign paroxysmal positional vertigo (BPPV) secondary to sudden sensorineural hearing loss (SNHL) and to analyze the correlation between canal paresis and the effectiveness of canalith repositioning procedures (CRPs) for the treatment. Study case series with chart review. Academic university hospital. We retrospectively reviewed 277 patients with BPPV. For sudden SNHL with a recent vertigo, patients underwent electronystagmography and bithermal caloric tests. We investigated the clinical characteristics including causes, type of involved semicircular canal, frequency of CRPs, treatment results, and canal paresis (CP). The diagnosis of BPPV accompanied by same-sided sudden SNHL was based on the results of head roll and Dix-Hallpike tests. Of 277 patients with BPPV, 24 (8.7%) had sudden SNHL. Multiple-canal involvement most commonly developed in post-sudden SNHL BPPV (p BPPV received a greater number of CRPs (2.95) than those with idiopathic BPPV (1.58) (p = 0.043). In patients with post-sudden SNHL BPPV, the average number of CRPs was 3.31 in the presence of CP and 2.1 sessions in the absence of CP (p = 0.030); the CP value was correlated with the frequency of CRPs (p = 0.020). In post-sudden SNHL BPPV, the worse the canal paresis becomes, the greater the number of CRPs will be needed for treatment; the simultaneous involvement of the posterior semicircular canal and horizontal semicircular canal is most common.

  5. Investigation of neutrophil-to-lymphocyte ratio and mean platelet volume in sudden hearing loss.

    Science.gov (United States)

    Kum, Rauf Oğuzhan; Ozcan, Muge; Baklaci, Deniz; Yurtsever Kum, Nurcan; Yilmaz, Yavuz Fuat; Unal, Adnan; Avci, Yonca

    2015-01-01

    Several theories attempt to explain the pathophysiology of sudden hearing loss. The objective of this study was to investigate the possible role of inflammation and atherothrombosis in sudden hearing loss patients through the neutrophil-to-lymphocyte ratio and mean platelet volume. Study design - retrospective cross-sectional historical cohort. This study was conducted on two groups: one with 59 individuals diagnosed with sudden hearing loss, and other with 59 healthy individuals with the same characteristics of gender and age distribution, neutrophil-to-lymphocyte ratio and mean platelet volume levels were measured in patients diagnosed with sudden hearing loss as well as in the control group, and it was verified whether these results interfered for a better or worse prognosis with treatment of sudden deafness. Neutrophil-to-lymphocyte ratio levels are much higher in patients diagnosed with sudden hearing loss compared to the control group. Similarly, mean levels of neutrophil-to-lymphocyte ratio are higher in non-recovered versus recovered patients (p=0.001). However, we could not find a correlation with mean platelet volume levels (p>0.05). Neutrophil-to-lymphocyte ratio is a quick and reliable indicator regarding diagnosis and prognosis of sudden hearing loss; on the other hand, mean platelet volume may be considered a less important indicator in this aspect. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  6. Towards Better Understanding of the Pathogenesis of Neuronal Respiratory Network in Sudden Perinatal Death

    Directory of Open Access Journals (Sweden)

    Riffat Mehboob

    2017-07-01

    Full Text Available Sudden perinatal death that includes the victims of sudden infant death syndrome, sudden intrauterine death syndrome, and stillbirth are heartbreaking events in the life of parents. Most of the studies about sudden perinatal death were reported from Italy, highlighting two main etiological factors: prone sleeping position and smoking. Other probable contributory factors are prematurity, male gender, lack of breastfeeding, respiratory tract infections, use of pacifiers, infant botulism, extensive use of pesticides and insecticides, etc. However, extensive studies across the world are required to establish the role of these factors in a different subset of populations. Previous studies confirmed the widely accepted hypothesis that neuropathology of the brainstem is one of the main cause of sudden perinatal death. This study is an effort to summarize the neuropathological evaluation of the brainstems and their association to sudden perinatal death. Brainstem nuclei in vulnerable infants undergo certain changes that may alter the sleep arousal cycle, cardiorespiratory control, and ultimately culminate in death. This review focuses on the roles of different brainstem nuclei, their pathologies, and the established facts in this regard in terms of it’s link to such deaths. This study will also help to understand the role of brainstem nuclei in controlling the cardiorespiratory cycles in sudden perinatal death and may provide a better understanding to resolve the mystery of these deaths in future. It is also found that a global initiative to deal with perinatal death is required to facilitate the diagnosis and prevention in developed and as well as developing countries.

  7. Definition, prevalence and characteristics of sudden exhaustion: a possible syndrome of fatigue in cancer?

    Science.gov (United States)

    Wu, Horng-Shiuann; Davis, Jean E

    2013-02-01

    Although sudden fatigue/exhaustion is a symptom expression that oncology clinicians frequently hear from their patients, empirical information about this phenomenon is limited. This study investigated the occurrence and characteristics of sudden fatigue in patients treated for breast cancer. This cross-sectional descriptive study enrolled 114 breast cancer chemotherapy outpatients from a cancer clinic and an urban teaching hospital in the Midwestern United States. Subjects were screened for sudden fatigue and completed an investigator-developed Sudden Onset of Fatigue Questionnaire on the day of their chemotherapy treatment. Descriptive statistics were used to examine prevalence and clinical characteristics. Approximately half (46 %) of the patients (age 31-67, 62 % Black, and 70 % unemployed) experienced sudden fatigue. The majority (81 %) reported more than one (median = 3) episode per day; 67 % of episodes lasted 60 min or less. The sudden fatigue was most likely (77 %) to occur between 10 a.m. and 5 p.m., while individuals were active (94 %). When it occurred, individuals stopped activities and sought immediate rest. It was described as abrupt exhaustion/weakness often (66 %) accompanied by other symptoms. Fatigue intensity before, during, and after a specific episode were 5, 9, and 5, respectively, on 0-10 (highest) scale. To better characterize sudden fatigue, a new descriptor, sudden exhaustion syndrome, which encompasses observed abrupt onset, transitory exhaustion/paralysis, and multiple symptoms, is proposed. Individuals may experience multiple occurrences of sudden exhaustion across a day, especially during activities. The syndrome needs to be recognized by oncology professionals. Patients should be educated about the syndrome to enhance sense of control and prevent harm.

  8. Altered Contralateral Auditory Cortical Morphology in Unilateral Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

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

    2015-12-01

    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. Prospective case study. Tertiary class A teaching hospital. Thirty-nine patients with left-side unilateral sudden sensorineural hearing loss and 47 patients with right-side unilateral sudden sensorineural hearing loss. Diagnostic. To compare the regional gray matter of unilateral sudden sensorineural hearing loss patients and healthy control participants. Compared with control groups, patients with left side unilateral sudden sensorineural hearing loss had significant gray matter reductions in the right middle temporal gyrus and right superior temporal gyrus, whereas patients with right side unilateral sudden sensorineural hearing loss showed gray matter decreases in the left superior temporal gyrus and left middle temporal gyrus. A significant negative correlation with the duration of the sudden sensorineural hearing loss (R = -0.427, p = 0.012 for left-side unilateral SSNHL and R = -0.412, p = 0.013 for right-side unilateral SSNHL) was also found in these brain areas. There was no region with increased gray matter found in both groups of unilateral sudden sensorineural hearing loss patients. This study confirms that detectable decreased contralateral auditory cortical morphological changes have occurred in unilateral SSNHL patients within the acute period by voxel-based morphometry methods. The gray matter volumes of these brain areas also perform a negative correlation with the duration of the disease, which suggests a gradual brain structural impairment after the progression of the disease.

  9. Adaptation to sudden unexpected loading of the low back - the effects of repeated trials

    DEFF Research Database (Denmark)

    Skotte, J.H.; Fallentin, N.; Pedersen, Mogens Theisen

    2004-01-01

    The purpose of this study was to investigate short-term changes in reactions to sudden unexpected loading of the low back. The study utilized a set-up where a horizontal force of 58 N pointing forward suddenly was applied to the upper part of the subject's trunk. EMG activity from the erector...... was lower for the first trial. This study showed that some subjects adapted to sudden unexpected loadings of the low back through a reduction in stopping time and a progression in EMG response during the first few trials. This possible adaptation to repeated trials have been overlooked in previous studies....

  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

    . The study included 23 participants and 14 controls. All were healthy without prior history of low back pain (LBP). The training group participated in a total of 18 training sessions during a 9-week period. The training focused on reactions to a variety of sudden trunk loadings. Before and after the training...... a high sustainability of the training effect. Conclusions. The results demonstrated a training-induced improvement of the response to sudden trunk loading that may be beneficial in workers, such as nurses, who are exposed to sudden trunk perturbations during patient handling....

  11. Bilateral sudden sensorineural hearing loss as an initial presentation of myelodysplastic syndrome.

    Science.gov (United States)

    Lee, Eun Jung; Yoon, Yong Joo

    2012-01-01

    This study reports an unusual case in which myelodysplastic syndrome presented bilateral sudden sensorineural hearing loss as the first symptom of the disease. The aural symptoms and signs such as tinnitus, dizziness, and hearing impairment of a hematologic disease are common. However, sudden hearing loss as the first manifestation of a hematologic disease is extremely rare. A 76-year-old woman presented with bilateral sudden hearing loss. The patient was found to have myelodysplastic syndrome during a workup for her hearing loss. Unfortunately, the patient's hearing loss did not improve after the medical treatment. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Sudden Infant Death Syndrome and the Genetics of Inflammation

    Science.gov (United States)

    Ferrante, Linda; Opdal, Siri Hauge

    2015-01-01

    Several studies report signs of slight infection prior to death in cases of sudden infant death syndrome (SIDS). Based on this, a hypothesis of an altered immunological homeostasis has been postulated. The cytokines are important cellular mediators that are crucial for infant health by regulating cell activity during the inflammatory process. The pro-inflammatory cytokines favor inflammation; the most important of these are IL-1α, IL-1β, IL-6, IL-8, IL-12, IL-18, TNF-α, and IFN-γ. These cytokines are controlled by the anti-inflammatory cytokines. This is accomplished by reducing the pro-inflammatory cytokine production, and thus counteracts their biological effect. The major anti-inflammatory cytokines are interleukin-1 receptor antagonist (IL-1ra), IL-4, IL-10, IL-11, and IL-13. The last decade there has been focused on genetic studies within genes that are important for the immune system, for SIDS with a special interest of the genes encoding the cytokines. This is because the cytokine genes are considered to be the genes most likely to explain the vulnerability to infection, and several studies have investigated these genes in an attempt to uncover associations between SIDS and different genetic variants. So far, the genes encoding IL-1, IL-6, IL-10, and TNF-α are the most investigated within SIDS research, and several studies indicate associations between specific variants of these genes and SIDS. Taken together, this may indicate that in at least a subset of SIDS predisposing genetic variants of the immune genes are involved. However, the immune system and the cytokine network are complex, and more studies are needed in order to better understand the interplay between different genetic variations and how this may contribute to an unfavorable immunological response. PMID:25750641

  13. Vertigo with sudden hearing loss: audio-vestibular characteristics.

    Science.gov (United States)

    Pogson, Jacob M; Taylor, Rachael L; Young, Allison S; McGarvie, Leigh A; Flanagan, Sean; Halmagyi, G Michael; Welgampola, Miriam S

    2016-10-01

    Acute vertigo with sudden sensorineural hearing loss (SSNHL) is a rare clinical emergency. Here, we report the audio-vestibular test profiles of 27 subjects who presented with these symptoms. The vestibular test battery consisted of a three-dimensional video head impulse test (vHIT) of semicircular canal function and recording ocular and cervical vestibular-evoked myogenic potentials (oVEMP, cVEMP) to test otolith dysfunction. Unlike vestibular neuritis, where the horizontal and anterior canals with utricular function are more frequently impaired, 74 % of subjects with vertigo and SSNHL demonstrated impairment of the posterior canal gain (0.45 ± 0.20). Only 41 % showed impairment of the horizontal canal gains (0.78 ± 0.27) and 30 % of the anterior canal gains (0.79 ± 0.26), while 38 % of oVEMPs [asymmetry ratio (AR) = 41.0 ± 41.3 %] and 33 % of cVEMPs (AR = 47.3 ± 41.2 %) were significantly asymmetrical. Twenty-three subjects were diagnosed with labyrinthitis/labyrinthine infarction in the absence of evidence for an underlying pathology. Four subjects had a definitive diagnosis [Ramsay Hunt Syndrome, vestibular schwannoma, anterior inferior cerebellar artery (AICA) infarction, and traction injury]. Ischemia involving the common-cochlear or vestibulo-cochlear branches of the labyrinthine artery could be the simplest explanation for vertigo with SSNHL. Audio-vestibular tests did not provide easy separation between ischaemic and non-ischaemic causes of vertigo with SSNHL.

  14. The Etiological Relationship Between Migraine and Sudden Hearing Loss.

    Science.gov (United States)

    Arslan, Yildiz; Arslan, İlker Burak; Aydin, Huriye; Yağiz, Özlem; Tokuçoğlu, Figen; Çukurova, İbrahim

    2017-12-01

    To investigate the relationship between sudden sensorineural hearing loss (SSNHL) and migraine, assess the prevalence of migraine in patients with idiopathic SSNHL, and determine a possible common vascular etiopathogenesis for migraine and SSNHL. Prospective cohort study. Tertiary referral center. This study initially assessed 178 SSNHL cases obtained from the Head and Neck Surgery Clinic patient database at a tertiary hospital in Turkey between January 2011 and March 2016. Ultimately, a total of 61 idiopathic SSNHL patients participated in the present study. İNTERVENTIONS:: Diagnostic. Cases with inflammation in the middle or inner ear; a retro cochlear tumor; autoimmune, infectious, functional, metabolic, neoplastic, traumatic, toxic, or vascular causes; Meniere's disease; otosclerosis; multiple sclerosis; and/or cerebrovascular diseases were excluded. Of the 61 idiopathic SSHNL patients, 34 were women (55.74%); and 24 (39.34%) had migraine, according to the criteria of the International Headache Society (IHS). The mean age of the migraine patients (Group 1) was 43.83 ± 13.16 years, and that of those without migraine (Group 2) was 51.05 ± 16.49 years. The groups did not significantly differ in terms of age, sex, or SSNHL recovery rates according to the Siegel criteria (p > 0.05). Ten of the migraine patients experienced visual aura, and the recovery rates of this group were higher. Additionally, the rate of total hearing loss was lower in Group 1 (n = 3, 12.5%) than in Group 2 (n = 10, 27%). SSNHL patients had a higher prevalence of migraine. Although those with migraine had higher recovery rates, the differences were not statistically significant.

  15. 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

    2016-01-01

    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. PMID:26863274

  16. Sudden infant death syndrome and the genetics of inflammation

    Directory of Open Access Journals (Sweden)

    Linda eFerrante

    2015-02-01

    Full Text Available Several studies report signs of slight infection prior to death in cases of sudden infant death syndrome (SIDS. Based on this, a hypothesis of an altered immunological homeostasis has been postulated. The cytokines are important cellular mediators that are crucial for infant health by regulating cell activity during the inflammatory process. The pro-inflammatory cytokines favor inflammation; the most important of these are IL-1α, IL-1β, IL-6, IL-8, IL-12, IL-18, TNF-α and IFN-γ. These cytokines are controlled by the anti-inflammatory cytokines. This is accomplished by reducing the pro-inflammatory cytokine production, and thus counteracts their biological effect. The major anti-inflammatory cytokines are interleukin 1 receptor antagonist (IL-1ra, IL-4, IL-10, IL-11, and IL-13. The last decade there has been focus on genetic studies within genes that are important for the immune system, for SIDS with a special interest of the genes encoding the cytokines. This is because the cytokine genes are considered to be the genes most likely to explain the vulnerability to infection, and several studies have investigated these genes in an attempt to uncover associations between SIDS and different genetic variants. So far the genes encoding IL-1, IL-6, IL-10 and TNF-α are the most investigated within SIDS research, and several studies indicates associations between specific variants of these genes and SIDS. Taken together this may indicate that in at least a subset of SIDS predisposing genetic variants of the immune genes are involved. However, the immune system and the cytokine network are complex, and more studies are needed in order to better understand the interplay between different genetic variations and how this may contribute to an unfavorable immunological response.

  17. Positive family history of idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Gäckler, A; Eickelmann, A K; Brors, D; Dazert, S; Epplen, J T; Kunstmann, E

    2010-12-01

    Idiopathic sudden sensorineural hearing loss (ISSNHL) is a heterogenic disease. Multiple factors influencing aetiology and prognosis are discussed. A retrospective clinical characterisation and analysis of family history of ISSNHL patients was performed to investigate influences on the disease. 186 inpatients diagnosed with ISSNHL were characterised by health records and a standardised questionnaire. Audiograms were observed. 75 controls that had never experienced an event of ISSNHL were questioned about family members being affected by ISSNHL. 63.4% of all patients could be assigned to at least one group with similar causes of ISSNHL (noise exposure, positive family history, infectious diseases, hypothyroidism and fibromuscular dysplasia). A positive family history for ISSNHL has not been reported so far. Therefore, we accentuated the characterisation of patients with positive family history. 21.4% affirmed a positive family history. In ten families, at least two family members were reported as ISSNHL patients. In comparison with patients with negative family history, they tend to be younger, experience more events of ISSNHL and show less improvement of hearing abilities under therapeutic treatment (non-significant). Differences intensified between smokers with positive family history and non-smokers with negative family history. Differences concerning average age were statistically significant (p = 0.001). Within 75 controls 11 families were reported with one member being affected by ISSNHL. In the control group we did not detect any family with more than one ISSNHL patient. The results indicated that patients with positive family history tend to have an aggravated course of ISSNHL. Further studies should help to confirm these results and to identify environmental or genetic factors leading to ISSNHL. This might support a better understanding of the aetiology of ISSNHL and offer new possibilities for prevention and therapy.

  18. Sudden Cardiac Arrest During Sports Activity in Middle Age

    Science.gov (United States)

    Marijon, Eloi; Uy-Evanado, Audrey; Reinier, Kyndaron; Teodorescu, Carmen; Narayanan, Kumar; Jouven, Xavier; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S.

    2015-01-01

    Background Sports-associated sudden cardiac arrests (SCAs) occur mostly during middle age. We sought to determine burden, characteristics, and outcomes of SCA during sports among middle aged residents of a large US community. Methods and Results SCA cases aged 35–65 years were identified in a large, prospective, population-based study (2002–2013), with systematic and comprehensive assessment of their lifetime medical history. Of the 1,247 SCA cases, 63 (5%) occurred during sports activities at a mean age of 51.1±8.8 years, yielding an incidence of 21.7 (95%CI 8.1–35.4) per million per year. The incidence varied significantly based on sex, with a higher incidence among men (RR 18.68 95%CI 2.50–139.56) for sports SCA, as compared to all other SCA (RR 2.58, 95%CI 2.12–3.13). Sports SCA was also more likely to be a witnessed event (87 vs. 53%, Psports-associated SCA (23.2 vs. 13.6%, P=0.04). Sports SCA cases presented with known pre-existing cardiac disease in 16%, ≥1 cardiovascular risk factor in 56%, and overall, 36% of cases had typical cardiovascular symptoms during the week preceding SCA. Conclusions Sports-associated SCA in middle age represents a relatively small proportion of the overall SCA burden, reinforcing the idea of the high benefit-low risk nature of sports activity. Especially in light of current population aging trends, our findings emphasize that targeted education could maximize both safety and acceptance of sports activity in the older athlete. PMID:25847988

  19. Clinical Study on 136 Children with Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Li, Feng-Jiao; Wang, Da-Yong; Wang, Hong-Yang; Wang, Li; Yang, Feng-Bo; Lan, Lan; Guan, Jing; Yin, Zi-Fang; Rosenhall, Ulf; Yu, Lan; Hellstrom, Sten; Xue, Xi-Jun; Duan, Mao-Li; Wang, Qiu-Ju

    2016-04-20

    The prevalence of sudden sensorineural hearing loss in children (CSSNHL) is consistently increasing. However, the pathology and prognosis of CSSNHL are still poorly understood. This retrospective study evaluated clinical characteristics and possible associated factors of CSSNHL. One hundred and thirty-six CSSNHL patients treated in Department of Otolaryngology-Head and Neck Surgery and Institute of Otolaryngology at Chinese PLA General Hospital between July 2008 and August 2015 were included in this study. These patients were analyzed for clinical characteristics, audiological characteristics, laboratory examinations, and prognostic factors. Among the 136 patients (151 ears), 121 patients (121 ears, 80.1%) were diagnosed with unilaterally CSSNHL, and 15 patients (30 ears, 19.9%) with bilateral CSSNHL. The complete recovery rate of CSSNHL was 9.3%, and the overall recovery rate was 37.7%. We found that initial degree of hearing loss, onset of treatment, tinnitus, the ascending type audiogram, gender, side of hearing loss, the recorded auditory brainstem response (ABR), and distortion product otoacoustic emissions (DPOAEs) had prognostic significance. Age, ear fullness, and vertigo had no significant correlation with recovery. Furthermore, the relevant blood tests showed 30.8% of the children had abnormal white blood cell (WBC) counts, 22.1% had elevated homocysteine levels, 65.8% had high alkaline phosphatase (ALP), 33.8% had high IgE antibody levels, and 86.1% had positive cytomegalovirus (CMV) IgG antibodies. CSSNHL commonly occurs unilaterally and results in severe hearing loss. Initial severe hearing loss and bilateral hearing loss are negative prognostic factors for hearing recovery, while positive prognostic factors include tinnitus, gender, the ascending type audiogram, early treatment, identifiable ABR waves, and DPOAEs. Age, vertigo, and ear fullness are not correlated with the recovery. Some serologic indicators, including the level of WBC, platelet

  20. Sudden sensorineural hearing loss in children: Etiology, management, and outcome.

    Science.gov (United States)

    Pitaro, Jacob; Bechor-Fellner, Avital; Gavriel, Haim; Marom, Tal; Eviatar, Ephraim

    2016-03-01

    Pediatric sudden sensorineural hearing loss (SSNHL) is uncommon, and the current guidelines for its management refer to adults. Our objective was to review cases of SSNHL in children and examine their etiologies, management, and outcome. We performed a retrospective chart review of all children under the age of 18 years treated for SSNHL between January 2003 and September 2014. Data recorded included age, gender, symptoms, onset of hearing loss, audiometric results, diagnostic studies, treatment, and outcome. Nineteen children were included. Mean age was 14 years (range 7-18 years). Male: female ratio was 9:10. Degree of hearing loss varied from mild to profound across the tested frequencies. Most common accompanying symptom was tinnitus. Serologic tests demonstrated recent Epstein-Barr virus infection in one patient and previous cytomegalovirus infection in six patients. Imaging studies included computed tomography scan (n=3) and/or magnetic resonance imaging (n=12). All imaging studies did not demonstrate any pathology. Treatment included systemic steroids in 19 (100%) children and intratympanic steroids in eight (42%). Hearing completely improved in three (16%) children, partially improved in nine (47%), and there was no improvement in six (32%). One child was lost to follow-up. Viral infection was a common finding in children with SSNHL and no pathological changes were demonstrated on imaging studies. In most patients (63%), hearing improvement was observed. Intratympanic steroid injection can benefit these children. Further studies are required to investigate the etiologies and establish guidelines for the management of SSNHL in children. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Sudden infant death syndrome in Brazil: fact or fancy?

    Directory of Open Access Journals (Sweden)

    Francesca Maia Woida

    Full Text Available CONTEXT AND OBJECTIVE: The true incidence of sudden infant death syndrome (SIDS in Brazil is unknown. The aim here was to identify SIDS cases in the city of Ribeirão Preto, State of São Paulo, between 2000 and 2005, in order to estimate its incidence. DESIGN AND SETTING: Retrospective analysis of data on live births and infant deaths in Ribeirão Preto and from autopsies of infants performed at the Death Verification Service of the Interior (SVOI between 2000 and 2005. RESULTS: There were 47,356 live births and 537 deaths, with infant mortality rates ranging from 12.9‰ to 10.9‰ of live births. Among the 24 infants who died possibly due to SIDS and who were autopsied at the SVOI, six were from families living in the municipality (0.13‰ of live births: three (50% were diagnosed as SIDS, and one each (16.66% as indeterminate cause, bronchoaspiration and cerebral edema. Two deaths occurred in the first month of life (33.33% and one each (16.66% at two, four, six and eight months. Two deaths each (33.33% occurred in the months of February and December, one each in August and October (16.66%. Four cases (66.7% occurred in the summer and one each (16.66% in winter and spring. There was 5:1 predominance of males over females. CONCLUSIONS: The frequency of SIDS was lower than what has been reported worldwide and in the Brazilian literature, thus suggesting underdiagnosis, indicating the lack of any specific postmortem protocol for SIDS identification and showing the need to implement this.

  2. Sudden infant death syndrome in Brazil: fact or fancy?

    Science.gov (United States)

    Woida, Francesca Maia; Saggioro, Fabiano Pinto; Ferro, Maria Alice Rossato; Peres, Luiz Cesar

    2008-01-02

    The true incidence of sudden infant death syndrome (SIDS) in Brazil is unknown. The aim here was to identify SIDS cases in the city of Ribeirão Preto, State of São Paulo, between 2000 and 2005, in order to estimate its incidence. Retrospective analysis of data on live births and infant deaths in Ribeirão Preto and from autopsies of infants performed at the Death Verification Service of the Interior (SVOI) between 2000 and 2005. There were 47,356 live births and 537 deaths, with infant mortality rates ranging from 12.9 to 10.9 of live births. Among the 24 infants who died possibly due to SIDS and who were autopsied at the SVOI, six were from families living in the municipality (0.13 of live births): three (50%) were diagnosed as SIDS, and one each (16.66%) as indeterminate cause, bronchoaspiration and cerebral edema. Two deaths occurred in the first month of life (33.33%) and one each (16.66%) at two, four, six and eight months. Two deaths each (33.33%) occurred in the months of February and December, one each in August and October (16.66%). Four cases (66.7%) occurred in the summer and one each (16.66%) in winter and spring. There was 5:1 predominance of males over females. The frequency of SIDS was lower than what has been reported worldwide and in the Brazilian literature, thus suggesting underdiagnosis, indicating the lack of any specific postmortem protocol for SIDS identification and showing the need to implement this.

  3. Comparison between Bilateral and Unilateral Sudden Sensorineural Hearing Loss

    Science.gov (United States)

    Bing, Dan; Wang, Da-Yong; Lan, Lan; Zhao, Li-Dong; Yin, Zi-Fang; Yu, Lan; Chen, Guo-Hui; Guan, Jing; Wang, Qiu-Ju

    2018-01-01

    Background: Bilateral sudden sensorineural hearing loss (BSSHL) is rare and assumed to be a different clinical entity compared to unilateral SSHL (USSHL). This study examined the differences between the idiopathic BSSHL and USSHL. Methods: Forty-six sequential BSSHL patients (Se-BSSHL) and 68 simultaneous BSSHL (Si-BSSHL) were consecutively admitted between June 2008 and December 2015. Two sets of patients served as control groups: (1) USSHL patients with healthy contralateral ear and (2) USSHL patients with contralateral preexisting hearing loss (USSHLwCHL). We retrospectively analyzed differences among four cohorts using analysis of variance, Kruskal-Wallis test, Welch's t-test, and Chi-square test as appropriate before and after propensity score matching (PSM) based on age, gender, and body mass index (BMI). Results: The prevalence of idiopathic BSSHL was 8.6% (114/1329) among the total SSHL patients. In the total cohort, USSHL patients tended to be younger, female, and tended to have lower BMI, renal parameters, and total cholesterol in addition to higher high-density lipoprotein compared to the other three groups. Most routine blood indicators, some coagulation markers, and immunoglobulin M (H = 13.4, P = 0.004) were significantly different among the study groups. After PSM, the major significant differences were found in audiometric characteristics. Si-BSSHL and Se-BSSHL patients demonstrated similar hearing thresholds as USSHL but were significantly better than the USSHLwCHL patients across most frequencies before and after treatment (H = 30.0, P hearing and H = 12.0, P = 0.007 for final hearing). Moreover, the BSSHL patients showed different hearing loss distribution patterns (more descending type, χ2 = 33.8, P = 0.001) with less hearing gain (H = 17.5, P hearing outcome rather than being classified as a completely different disease entity compared to USSHL. PMID:29363646

  4. Clinical Study on 136 Children with Sudden Sensorineural Hearing Loss

    Science.gov (United States)

    Li, Feng-Jiao; Wang, Da-Yong; Wang, Hong-Yang; Wang, Li; Yang, Feng-Bo; Lan, Lan; Guan, Jing; Yin, Zi-Fang; Rosenhall, Ulf; Yu, Lan; Hellstrom, Sten; Xue, Xi-Jun; Duan, Mao-Li; Wang, Qiu-Ju

    2016-01-01

    Background: The prevalence of sudden sensorineural hearing loss in children (CSSNHL) is consistently increasing. However, the pathology and prognosis of CSSNHL are still poorly understood. This retrospective study evaluated clinical characteristics and possible associated factors of CSSNHL. Methods: One hundred and thirty-six CSSNHL patients treated in Department of Otolaryngology-Head and Neck Surgery and Institute of Otolaryngology at Chinese PLA General Hospital between July 2008 and August 2015 were included in this study. These patients were analyzed for clinical characteristics, audiological characteristics, laboratory examinations, and prognostic factors. Results: Among the 136 patients (151 ears), 121 patients (121 ears, 80.1%) were diagnosed with unilaterally CSSNHL, and 15 patients (30 ears, 19.9%) with bilateral CSSNHL. The complete recovery rate of CSSNHL was 9.3%, and the overall recovery rate was 37.7%. We found that initial degree of hearing loss, onset of treatment, tinnitus, the ascending type audiogram, gender, side of hearing loss, the recorded auditory brainstem response (ABR), and distortion product otoacoustic emissions (DPOAEs) had prognostic significance. Age, ear fullness, and vertigo had no significant correlation with recovery. Furthermore, the relevant blood tests showed 30.8% of the children had abnormal white blood cell (WBC) counts, 22.1% had elevated homocysteine levels, 65.8% had high alkaline phosphatase (ALP), 33.8% had high IgE antibody levels, and 86.1% had positive cytomegalovirus (CMV) IgG antibodies. Conclusions: CSSNHL commonly occurs unilaterally and results in severe hearing loss. Initial severe hearing loss and bilateral hearing loss are negative prognostic factors for hearing recovery, while positive prognostic factors include tinnitus, gender, the ascending type audiogram, early treatment, identifiable ABR waves, and DPOAEs. Age, vertigo, and ear fullness are not correlated with the recovery. Some serologic indicators

  5. Endothelial dysfunction in patients with sudden sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Nezamoddin Berjis

    2016-01-01

    Full Text Available Background: Endothelial dysfunction probably has a role in the etiology of sudden sensorineural hearing loss (SSNHL. The aim of this study was determining of the relationship between endothelial dysfunction and SSNHL. Materials and Methods: In a case-control study, 30 patients with SSNHL and 30 otherwise healthy age and sex-matched controls were studied. Demographic data gathered included age, gender, family history of SSNHL, and history of smoking, cardiovascular disease, hypertension, diabetes, and dyslipidemia. Laboratory data included measurement of hemoglobin, fasting blood sugar (FBS and lipid profile. Endothelial function was assessed by measuring flow-mediated dilation (FMD. Results: The two groups were the same in age (47.9 ± 9.3 and 48.1 ± 9.6 years, P = 0.946 with female/male ratio of 1:1 in both groups. Diabetes and dyslipidemia were more frequent in patients than controls (20% vs. 0%, P = 0.024. Brachial artery diameter was greater in patients than controls before (4.24 ± 0.39 vs. 3.84 ± 0.23 mm, P < 0.001 and after ischemia (4.51 ± 0.43 vs. 4.28 ± 0.27 mm, P = 0.020, but FMD was lower in patients than controls (6.21 ± 3.0 vs. 11.52 ± 2.30%, P < 0.001. Binary logistic regression analysis showed that FMD was associated with SSNHL independent from FBS and lipid profile (odds ratio [95% confidence interval] =0.439 [0.260-0.740], P = 0.002. Conclusion: Endothelial dysfunction, among other cardiovascular risk factors, is associated with SSNHL. This association is independent from other cardiovascular risk factors including diabetes and dyslipidemia.

  6. Sudden cardiac death: a nationwide cohort study among the young.

    Science.gov (United States)

    Risgaard, Bjarke

    2016-12-01

    Sudden cardiac death (SCD) is a tragic event affecting millions of individuals worldwide. Although several studies have investigated the epidemiology of SCD, these studies may have been affected by reporting and referral biases, which are reflected in the very different incidence rates and causes of deaths that have previously been reported. Among SCD victims aged children is of particular interest. These deaths are often described as a part of the deaths of young adolescents up to 40 years of age, and the focus has recently shifted towards the prevention of these deaths. The SCD incidence rate among patients with psychiatric disease has also gained significant attention. Finally, the incidence rate of sports-related sudden cardiac death (SrSCD) has been thoroughly investigated in young competitive athletes. However, whether competitive athletes are at increased risk for SrSCD compared with non-competitive athletes remains unknown. These data should be available prior to discussing optimal screening strategies for (competitive) athletes. In this thesis, we investigated the SCD burden in Danes aged 1-49 years between 2007 and 2009. By using the unique Danish death certificates, autopsy reports, discharge summaries, and registries, we included all deaths in a nationwide setting. We described the incidence rates and causes of death, and we performed a sub-group analysis of SCD in children (1-18 years, 2000-2006). Furthermore, we described the SCD burden in competitive and non-competitive athletes and investigated how often SCD occurred in patients with previous psychiatric disease. SCD has an incidence rate of 8.6 (95% confidence interval (CI) 8.0-9.2) per 100,000 person-years in persons aged 1-49 years. We found a steep increase in the incidence rate with increasing age, reaching 38.5 (95% CI 32.9-44.7) per 100,000 person-years in persons aged 48-49 years. The most common causes of death were coronary artery disease (CAD) (n = 158) and sudden unexplained death (SUD

  7. Sudden unexplained death in childhood. An audit of the quality of Autopsy reporting

    LENUS (Irish Health Repository)

    Treacy, A

    2013-03-01

    Cases of sudden unexplained death in childhood (SUDC) in Ireland in children aged >1year and <5 years were examined in order to assess the quality of autopsy reporting. All SUDC cases are notified to and documented by the National Sudden Infant Death Register (NSIDR) in Ireland along with all cases of sudden infant death syndrome (SIDS) referring to sudden infant deaths less than one year of age. The database of the NSIDR in Ireland was interrogated and cases of SIDS and SUDC were compared over a fifteen-year period (1995-2009). SIDS cases whose autopsies were conducted in the same hospital in the same year as the index SUDC case were used for comparison. The autopsy report for each case was examined and modified Rushton(MR) scores 1\\r\

  8. Prolonged QTc interval and risk of sudden cardiac death in a population of older adults

    DEFF Research Database (Denmark)

    Straus, Sabine M J M; Kors, Jan A; De Bruin, Marie L

    2006-01-01

    , >470 ms in women) was associated with a three-fold increased risk of sudden cardiac death (hazard ratio, 2.5; 95% confidence interval, 1.3 to 4.7), after adjustment for age, gender, body mass index, hypertension, cholesterol/high-density lipoprotein ratio, diabetes mellitus, myocardial infarction...... of the QTc interval has been associated with ventricular arrhythmias, but in most population-based studies no consistent association was found between QTc prolongation and total or cardiovascular mortality. Only very few of these studies specifically addressed sudden cardiac death. METHODS: This study......). The association between a prolonged QTc interval and sudden cardiac death was estimated using Cox proportional hazards analysis. RESULTS: During an average follow-up period of 6.7 years (standard deviation, 2.3 years) 125 patients died of sudden cardiac death. An abnormally prolonged QTc interval (>450 ms in men...

  9. Regeneration and tanoak mortality in coast redwood stands affected by sudden oak death

    Science.gov (United States)

    Benjamin S. Ramage; Kevin L. OHara; Alison B. Forreste

    2012-01-01

    Sudden oak death, an emerging disease caused by the exotic pathogen Phytophthora ramorum, is impacting coast redwood (Sequoia sempervirens) forests throughout coastal California. The most severely affected species, tanoak (Notholithocarpus densiflorus), is currently widespread and abundant in the redwood...

  10. AN AUDIT OF THE SUDDEN-INFANT-DEATH-SYNDROME PREVENTION PROGRAM IN THE AUCKLAND REGION

    NARCIS (Netherlands)

    Obdeijn, M. C.; Tonkin, S.; Mitchell, E. A.

    1995-01-01

    Aim. An audit of the sudden infant death syndrome (SIDS) prevention programme in the Auckland region. Methods. 107 health professionals working in antenatal classes, postnatal wards, domiciliary midwifery and the Plunket Society were interviewed. Results. Maternal smoking and infant sleeping

  11. Acute otitis media associated bilateral sudden hearing loss: case report and literature review.

    Science.gov (United States)

    Smith, A; Gutteridge, I; Elliott, D; Cronin, M

    2017-07-01

    Sudden sensorineural hearing loss is a rare otological condition with potential for dire outcomes including permanent hearing loss. Although the majority of cases are deemed idiopathic, bilateral sudden sensorineural hearing loss represents a rare subset typically related to systemic conditions, with higher morbidity and mortality. A controversial association with acute otitis media has been reported, with few bilateral cases published in the literature. A very rare case of bilateral sudden sensorineural hearing loss associated with acute otitis media is described, with a review of the literature. The limited evidence available suggests that acute otitis media with tinnitus and/or bacterial pathology may have an increased risk of sudden sensorineural hearing loss, which is consistent with the case described. Although there is no sufficiently powered published evidence to provide definitive treatment guidelines, the literature reviewed suggests that early myringotomy and antibiotics may greatly improve treatment outcomes.

  12. Epilepsy and sudden death: personal reflections and call for global action.

    Science.gov (United States)

    Lathers, Claire M

    2009-07-01

    To solve the mystery of sudden unexpected death in persons with epilepsy (SUDEP), a global focus is needed to identify persons at risk, develop treatment regimens, and prevent its occurrence. A world wide network of professionals must focus on basic scientific research programs and clinical and epidemiology studies. Team work among different multidisciplinary professionals in clinical settings and within and among laboratories should address the global issues of SUDEP. If the correct term 'SUDEP' is used on autopsy reports and if verbal autopsies postmortem are conducted when needed, the true incidence of SUDEP may be found to be much higher than previously thought and the market for new antiepileptics and other drugs to prevent SUDEP will be larger. Symposia should discuss new data and lessons learned from the last 20 to 30 years to be applied by scientists and clinicians worldwide to gain a better understanding of SUDEP. 'Think out of the box' when evaluating an established animal model with potential for modification(s) to study mechanism(s) of SUDEP. Multiple relevant animal models are needed to understand the pathophysiology of SUDEP, hypothesize about effective treatments, develop small pilot studies in persons with epilepsy, and conduct confirmatory large-scale clinical trials. The fields of pharmacology, clinical pharmacology, and cardiology have much to offer as we work to improve compliance, develop new antiepileptic drugs, and apply different categories of drugs to resolve the mystery of SUDEP. Ambulatory simultaneous EKG and EEG telemetry monitoring of patients at risk for sudden death will help identify cardiac vs. brain epileptogenic triggers for treatment to decrease risk of SUDEP. Respiratory function monitoring is also needed. Academic fellowships and competitions for medical students, postdoctoral fellows, residents and faculty will attract medical and graduate trainees to work on SUDEP. Grant funding is essential to move the SUDEP knowledge base

  13. Prediction of hearing outcomes by multiple regression analysis in patients with idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Suzuki, Hideaki; Tabata, Takahisa; Koizumi, Hiroki; Hohchi, Nobusuke; Takeuchi, Shoko; Kitamura, Takuro; Fujino, Yoshihisa; Ohbuchi, Toyoaki

    2014-12-01

    This study aimed to create a multiple regression model for predicting hearing outcomes of idiopathic sudden sensorineural hearing loss (ISSNHL). The participants were 205 consecutive patients (205 ears) with ISSNHL (hearing level ≥ 40 dB, interval between onset and treatment ≤ 30 days). They received systemic steroid administration combined with intratympanic steroid injection. Data were examined by simple and multiple regression analyses. Three hearing indices (percentage hearing improvement, hearing gain, and posttreatment hearing level [HLpost]) and 7 prognostic factors (age, days from onset to treatment, initial hearing level, initial hearing level at low frequencies, initial hearing level at high frequencies, presence of vertigo, and contralateral hearing level) were included in the multiple regression analysis as dependent and explanatory variables, respectively. In the simple regression analysis, the percentage hearing improvement, hearing gain, and HLpost showed significant correlation with 2, 5, and 6 of the 7 prognostic factors, respectively. The multiple correlation coefficients were 0.396, 0.503, and 0.714 for the percentage hearing improvement, hearing gain, and HLpost, respectively. Predicted values of HLpost calculated by the multiple regression equation were reliable with 70% probability with a 40-dB-width prediction interval. Prediction of HLpost by the multiple regression model may be useful to estimate the hearing prognosis of ISSNHL. © The Author(s) 2014.

  14. Leopard syndrome and hypertrophic cardiomyopathy: an association related to sudden death.

    Science.gov (United States)

    Antunes, Murillo de Oliveira; Arteaga, Edmundo; Matsumoto, Afonso Yoshikiro; Ianni, Barbara Maria

    2009-06-01

    We describe an uncommon association between Leopard syndrome and hypertrophic cardiomyopathy in a 27-year-old woman, who was little symptomatic and came for sudden death risk stratification and prevention. She has a rare syndrome, whose symptoms are maculae over the body and abnormalities in eyes, genital organs, heart and in growth. Association of hypertrophic cardiomyopathy with sudden death risk factors determined the implantation of cardioverter-defibrillator (ICD) for primary prevention.

  15. National athletic trainers' association position statement: preventing sudden death in sports.

    Science.gov (United States)

    Casa, Douglas J; Guskiewicz, Kevin M; Anderson, Scott A; Courson, Ronald W; Heck, Jonathan F; Jimenez, Carolyn C; McDermott, Brendon P; Miller, Michael G; Stearns, Rebecca L; Swartz, Erik E; Walsh, Katie M

    2012-01-01

    To present recommendations for the prevention and screening, recognition, and treatment of the most common conditions resulting in sudden death in organized sports. Cardiac conditions, head injuries, neck injuries, exertional heat stroke, exertional sickling, asthma, and other factors (eg, lightning, diabetes) are the most common causes of death in athletes. These guidelines are intended to provide relevant information on preventing sudden death in sports and to give specific recommendations for certified athletic trainers and others participating in athletic health care.

  16. [Sudden cardiac death in familial hypertrophic cardiomyopathy. Identification of high-risk patients].

    Science.gov (United States)

    Pellnitz, C; Geier, C; Perrot, A; Dietz, R; Osterziel, K J; Haverkamp, W

    2005-05-06

    Hypertrophic cardiomyopathy (HCM) is a relatively frequent, genetically determined primary cardiomyopathy, characterized by most often asymmetric hypertrophy of the ventricular septum with or without systolic obstruction of the left ventricular outflow tract. HCM is a genetically heterogeneous disease, with 12 different disease-causing genes beeing indentified to date. Histologically the disease is characterized by hypertophy and disarray of myofibrils as well as by an increase in myocardial fibrosis. Clinically, these changes may lead to palpitations, dyspnoe on exertion, and/or angina pectoris. However, they also lead to an increased propensity to the development of severe ventricular tachyarrhythmias and sudden cardiac death. The incidence of sudden death is significantly increased in HCM, particularly in affected young subjects. Risk stratification in HCM should include a complete clinical-cardiological evaluation that should also consider new diagnostic features, e. g. MR imaging. Major risk factors for sudden cardiac death include a survived cardiac arrest (ventricular fibrillation), non-sustained and sustained ventricular tachycardia, a history of premature familial sudden death, unexplained syncope, an abnormal blood pressure response on exercise, and left ventricular thickness greater than or equal to 3 cm. Ideally, risk stratification should also include genetic testing, since some gene mutations seem to be associated with a higher risk for sudden cardiac death than others. However, genetic testing in HCM in not yet available on a routine basis. The implantation of a cardioverter/defibrillator is first-line therapy in patients with documented ventricular tachycardia/fibrillation or patients who have survived sudden cardiac death. These devices also play an important role in the primary prevention of sudden cardiac death in HCM. Algorithms and scores are available to estimate the risk of sudden death, however, the decision to implant a cardioverter

  17. Using a pacifier to decrease sudden infant death syndrome: an emergency department educational intervention

    OpenAIRE

    Walsh, Paul; Vieth, Teri; Rodriguez, Carolina; Lona, Nicole; Molina, Rogelio; Habebo, Emnet; Caldera, Enrique; Garcia, Cynthia; Veazey, Gregory

    2014-01-01

    Background. Pacifier use decreases the risk of sudden infant death syndrome (SIDS). An emergency department (ED) visit may provide an opportunistic ‘teachable moment’ for parents. Objectives. To test the hypotheses (1) that caregivers were less familiar with the role of pacifiers in sudden infant death (SIDS) prevention than other recommendations, and (2) that an ED educational intervention would increase pacifier use in infants younger than six months, and (3) that otitis media would not occ...

  18. Sudden Sensorineural Hearing Loss in the Only Hearing Ear: Large Vestibular Aqueduct Syndrome

    Directory of Open Access Journals (Sweden)

    Kemal Koray Bal

    2016-01-01

    Full Text Available Sudden hearing loss in the only hearing ear cases are rarely published in the English literature; most of the cases are idiopathic. It is an otologic emergency needing urgent treatment. Delayed diagnosis can interfere with patient’s social life with interrupting the verbal communication. In this case report we presented a 33-year-old female patient having sudden sensorineural hearing loss in the only hearing ear diagnosed as bilateral large vestibular aqueduct syndrome.

  19. Sudden post-traumatic sciatica caused by a thoracic spinal meningioma

    OpenAIRE

    Mariniello, Giuseppe; Malacario, Francesca; Dones, Flavia; Severino, Rocco; Ugga, Lorenzo; Russo, Camilla; Elefante, Andrea; Maiuri, Francesco

    2016-01-01

    Spinal meningiomas usually present with slowly progressive symptoms of cord and root compression, while a sudden clinical onset is very rare. A 35-year-old previously symptom-free woman presented sudden right sciatica and weakness of her right leg following a fall with impact to her left foot. A neurological examination showed paresis of the right quadriceps, tibial and sural muscles, increased bilateral knee and ankle reflexes and positive Babinski sign. Magnetic resonance imaging (MRI) reve...

  20. Lyme disease associated with sudden sensorineural hearing loss: case report and literature review.

    Science.gov (United States)

    Peeters, Natalie; van der Kolk, Brigitta Y M; Thijsen, Steven F T; Colnot, David R

    2013-07-01

    Is sudden sensorineural hearing loss associated with Lyme disease in adults? A retrospective case report and a systematic literature search in PubMed and Embase were performed. We describe a patient presenting with sudden sensorineural hearing loss, followed by a facial paralysis, which could be attributed to Lyme disease confirmed by positive serology and a positive immunoblot. She was successfully treated with ceftriaxone, with recovery of the facial paralysis, although no recovery of the hearing loss was observed. A systematic literature search resulted in 4 relevant and valid articles revealing that confirmed positive serology for Borrelia burgdorferi varies from 0% to 21.3%, suggesting active Lyme disease as a cause in patients with sudden sensorineural hearing loss. Two studies demonstrated a significantly higher incidence of confirmed positive serology for Borrelia burgdorferi as compared with the incidence in the general local population. Literature suggests that sudden sensorineural hearing loss may coincide with Borrelia burgdorferi infection. A higher incidence of confirmed positive serology for Borrelia burgdorferi in patients with sudden deafness seems to be depending on the country and on the tests used to confirm Lyme disease. This should be taken into account if serologic testing for Lyme disease in patients with sudden deafness is considered.

  1. Sudden infant death syndrome: are we any closer to identifying which infants will be affected?

    Directory of Open Access Journals (Sweden)

    Ramirez TL

    2013-03-01

    Full Text Available Tara L Ramirez, Michael H MalloyDepartment of Pediatrics, The University of Texas Medical Branch, Galveston, TX, USAAbstract: Sudden infant death syndrome is a complex and multifactoral process. The classification and definition of the syndrome has changed over time. As knowledge in the genetics of this complex syndrome continues to advance, additional causes of vulnerability have been found, but no single cause has yet been discovered. Over the last 40 years there have also been many advances in the identification of risk factors that make a given infant more vulnerable to succumbing to sudden infant death. There have also been great strides made in decreasing the number of infant deaths from this syndrome by modification of these risk factors, most notably with the initiation of the Back to Sleep campaign. With the initiation of the Safe to Sleep campaign there is hope that sudden infant death syndrome as a component of all sudden unexpected infant deaths can be further reduced.Keywords: sudden infant death syndrome, sudden unexpected death of infancy, risk factors, sleep-related infant death, crib death, cot death

  2. Presentation and survival of prehospital apparent sudden infant death syndrome.

    Science.gov (United States)

    Smith, Matthew P; Kaji, Amy; Young, Kelly D; Gausche-Hill, Marianne

    2005-01-01

    Prehospital providers are often involved in the resuscitation of apparent sudden infant death syndrome (SIDS) victims; however, data are few on the presentation and outcome of these patients. To describe the presentation and determine the survival rate of infants who have an unwitnessed, prehospital arrest consistent with SIDS (apparent SIDS), and to compare the presentation of infants with a final diagnosis of SIDS with those who presented as apparent SIDS but had a different final diagnosis. This was a secondary analysis of data from a controlled trial whose methodology has been previously described. The setting was two large, urban emergency medical services (EMS) systems of Los Angeles and Orange Counties, California. The population included 113 apparent SIDS victims from the original interventional study who had a prehospital, unwitnessed arrest consistent with SIDS, defined by the scenario of an infant aged =12 months being placed to sleep and later found in full arrest (pulseless and apneic). Data collected included ethnicity, gender, arrest etiology, signs of death (lividity, rigor mortis), prehospital interventions, return of spontaneous circulation (ROSC), arrest rhythm, code 3 transport (lights and sirens), and survival to hospital discharge. One hundred ten of 113 apparent SIDS patients had survival data; 0 of 110 (95% CI 0% to 3.3%) survived, although ROSC was achieved in 5%; for three patients data on survival were missing. Arrest rhythms were determined in 94% of the subjects: asystole 87%, pulseless electrical activity (PEA) 8%, and ventricular fibrillation 4%. Only 50 of 113 (44%) of the EMS records documented code 3 transport; the remainder of the records were ambiguous. SIDS was the final coroner's diagnosis for 79 of 113 (70%) of the cases. Other causes of death in these apparent SIDS victims included respiratory causes (12%), asphyxiation (3%), abuse (2%), congenital heart disease (2%), sepsis (2%), other (4%), and unknown (5%). Apparent SIDS

  3. Worldwide impacts of sudden stratospheric warmings on the ionosphere and thermosphere

    Science.gov (United States)

    Goncharenko, Larisa; Coster, Anthea; Zhang, Shun-Rong; Erickson, Phillip; Aponte, Nestor; Harvey, V. Lynn; Pedatella, Nicholas; Maute, Astrid

    2016-04-01

    Recent studies have demonstrated large variations in the low-latitude ionosphere during strong, persistent meteorological disturbances known as sudden stratospheric warmings. Several possible lower/upper atmosphere coupling mechanisms were identified, including changes in the dynamics of the background neutral atmosphere, modification of solar and lunar tides, and subsequent variations in electric field. We extend these studies using observations by GNSS TEC receivers, by several ionosondes located at low, middle, and high latitudes, and by Jicamarca, Arecibo and Millstone Hill incoherent scatter radars to investigate large-scale ionospheric disturbances for several SSW events. To separate ionospheric anomalies associated with SSW from regular ionospheric behavior, we develop an empirical model of ionospheric parameters (TEC, NmF2) using available long-term data records (10-40 years of data depending on the instrument). The models describe variations in parameters for each longitude/latitude bin (or ionosonde location) as a function of solar activity, geomagnetic activity, day of year, and local time. Ionospheric anomalies are obtained as the difference between the observations and the empirical model. Ionospheric anomalies are observed for both major and minor SSW events, reaching 50-100% variation from expected seasonal behavior for major SSW events and 30-60% variation for minor SSW events. The largest variations in the daytime TEC and NmF2 are observed both in the crests of equatorial ionization anomaly and at 40-60S (geodetic). Recent expansion of GNSS TEC receiver network to high latitudes in the southern hemisphere indicates that SSW anomalies are communicated across the globe and associated with ionospheric disturbances even over Antarctica. Observational studies focused on SSW events present an important opportunity to better understand processes governing the behavior of the Earth's ionosphere and thermosphere. We use examples of observations from

  4. Mapping Global Potential Risk of Mango Sudden Decline Disease Caused by Ceratocystis fimbriata

    Science.gov (United States)

    Oliveira, Leonardo S. S.; Alfenas, Acelino C.; Neven, Lisa G.; Al-Sadi, Abdullah M.

    2016-01-01

    The Mango Sudden Decline (MSD), also referred to as Mango Wilt, is an important disease of mango in Brazil, Oman and Pakistan. This fungus is mainly disseminated by the mango bark beetle, Hypocryphalus mangiferae (Stebbing), by infected plant material, and the infested soils where it is able to survive for long periods. The best way to avoid losses due to MSD is to prevent its establishment in mango production areas. Our objectives in this study were to: (1) predict the global potential distribution of MSD, (2) identify the mango growing areas that are under potential risk of MSD establishment, and (3) identify climatic factors associated with MSD distribution. Occurrence records were collected from Brazil, Oman and Pakistan where the disease is currently known to occur in mango. We used the correlative maximum entropy based model (MaxEnt) algorithm to assess the global potential distribution of MSD. The MaxEnt model predicted suitable areas in countries where the disease does not already occur in mango, but where mango is grown. Among these areas are the largest mango producers in the world including India, China, Thailand, Indonesia, and Mexico. The mean annual temperature, precipitation of coldest quarter, precipitation seasonality, and precipitation of driest month variables contributed most to the potential distribution of MSD disease. The mango bark beetle vector is known to occur beyond the locations where MSD currently exists and where the model predicted suitable areas, thus showing a high likelihood for disease establishment in areas predicted by our model. Our study is the first to map the potential risk of MSD establishment on a global scale. This information can be used in designing strategies to prevent introduction and establishment of MSD disease, and in preparation of efficient pest risk assessments and monitoring programs. PMID:27415625

  5. Portfolio management under sudden changes in volatility and heterogeneous investment horizons

    Science.gov (United States)

    Fernandez, Viviana; Lucey, Brian M.

    2007-03-01

    We analyze the implications for portfolio management of accounting for conditional heteroskedasticity and sudden changes in volatility, based on a sample of weekly data of the Dow Jones Country Titans, the CBT-municipal bond, spot and futures prices of commodities for the period 1992-2005. To that end, we first proceed to utilize the ICSS algorithm to detect long-term volatility shifts, and incorporate that information into PGARCH models fitted to the returns series. At the next stage, we simulate returns series and compute a wavelet-based value at risk, which takes into consideration the investor's time horizon. We repeat the same procedure for artificial data generated from semi-parametric estimates of the distribution functions of returns, which account for fat tails. Our estimation results show that neglecting GARCH effects and volatility shifts may lead to an overestimation of financial risk at different time horizons. In addition, we conclude that investors benefit from holding commodities as their low or even negative correlation with stock and bond indices contribute to portfolio diversification.

  6. Pengaruh Rasio Step pada Sudden Enlargement Channel terhadap Heat Flux Kondensasi di Porous Media

    Directory of Open Access Journals (Sweden)

    Djoko Hari Praswanto

    2017-08-01

    Full Text Available One of the most significant parameter in air conditioning problems is air humidity. A porous media can be used as a heat exchanger component in order to increase the heat transfer performance which is significantly depends on the heat flux values inside of them. To determine the heat flux value, a following test section was modeled in this research. A vapor passed through a channel whereas a particular porous media made of active carbon acted as its heat exchanger media. However, the sudden enlargement at the inlet of channel could affect the homogeneity of temperature distributions and also caused some several turbulencies. The research method is vapor flowed over the porous media for 60 minute with temperature of 300oC.The vapor velocity is varied from 1 m/s to 3 m/s and the step ratio also varied between 0 until 1.66. From the experiment shows the bigger step ratio and vapor velocity results the bigger heat flux and air humidity after passed through the low porous media. Heat transfer was occured in porous media including convection heat transfer with the value of Gr/Re2 smaller than 1.

  7. Sudden death mechanisms in nonischemic cardiomyopathies: Insights gleaned from clinical implantable cardioverter-defibrillator trials.

    Science.gov (United States)

    Steinberg, Benjamin A; Mulpuru, Siva K; Fang, James C; Gersh, Bernard J

    2017-12-01

    Sudden cardiac death (SCD) represents a major cause of death among patients with heart failure. Although scar-based, macroreentrant ventricular tachycardia/ventricular fibrillation is the primary etiology for SCD among patients with ischemic cardiomyopathy, a more diverse set of mechanisms and substrates is likely at play for the diverse group of patients characterized by nonischemic dilated cardiomyopathy (NICM). These causes may include scar-based reentry, but also neurohormonal stimulation (sympathetic, parasympathetic, renin-angiotensin-aldosterone), inflammation, and nonarrhythmic processes occurring in the context of a genetic predisposition. In addition to basic and translational science, observations from large randomized clinical trials of implantable cardioverter-defibrillators (ICDs) can also offer insight and support for specific mechanisms of SCD in these patients. This review will discuss the background of SCD in NICM, its potential mechanisms based on experimental and theoretical models, and the evidence for these mechanisms that can be derived from clinical trials of ICD therapy. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  8. Brainstem serotonergic deficiency in sudden infant death syndrome.

    Science.gov (United States)

    Duncan, Jhodie R; Paterson, David S; Hoffman, Jill M; Mokler, David J; Borenstein, Natalia S; Belliveau, Richard A; Krous, Henry F; Haas, Elisabeth A; Stanley, Christina; Nattie, Eugene E; Trachtenberg, Felicia L; Kinney, Hannah C

    2010-02-03

    Sudden infant death syndrome (SIDS) is postulated to result from abnormalities in brainstem control of autonomic function and breathing during a critical developmental period. Abnormalities of serotonin (5-hydroxytryptamine [5-HT]) receptor binding in regions of the medulla oblongata involved in this control have been reported in infants dying from SIDS. To test the hypothesis that 5-HT receptor abnormalities in infants dying from SIDS are associated with decreased tissue levels of 5-HT, its key biosynthetic enzyme (tryptophan hydroxylase [TPH2]), or both. Autopsy study conducted to analyze levels of 5-HT and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA); levels of TPH2; and 5-HT(1A) receptor binding. The data set was accrued between 2004 and 2008 and consisted of 41 infants dying from SIDS (cases), 7 infants with acute death from known causes (controls), and 5 hospitalized infants with chronic hypoxia-ischemia. Serotonin and metabolite tissue levels in the raphé obscurus and paragigantocellularis lateralis (PGCL); TPH2 levels in the raphé obscurus; and 5-HT(1A) binding density in 5 medullary nuclei that contain 5-HT neurons and 5 medullary nuclei that receive 5-HT projections. Serotonin levels were 26% lower in SIDS cases (n = 35) compared with age-adjusted controls (n = 5) in the raphé obscurus (55.4 [95% confidence interval {CI}, 47.2-63.6] vs 75.5 [95% CI, 54.2-96.8] pmol/mg protein, P = .05) and the PGCL (31.4 [95% CI, 23.7-39.0] vs 40.0 [95% CI, 20.1-60.0] pmol/mg protein, P = .04). There was no evidence of excessive 5-HT degradation assessed by 5-HIAA levels, 5-HIAA:5-HT ratio, or both. In the raphé obscurus, TPH2 levels were 22% lower in the SIDS cases (n = 34) compared with controls (n = 5) (151.2% of standard [95% CI, 137.5%-165.0%] vs 193.9% [95% CI, 158.6%-229.2%], P = .03). 5-HT(1A) receptor binding was 29% to 55% lower in 3 medullary nuclei that receive 5-HT projections. In 4 nuclei, 3 of which contain 5-HT neurons, there was a decrease with

  9. Multiple serotonergic brainstem abnormalities in sudden infant death syndrome.

    Science.gov (United States)

    Paterson, David S; Trachtenberg, Felicia L; Thompson, Eric G; Belliveau, Richard A; Beggs, Alan H; Darnall, Ryan; Chadwick, Amy E; Krous, Henry F; Kinney, Hannah C

    2006-11-01

    The serotonergic (5-hydroxytryptamine [5-HT]) neurons in the medulla oblongata project extensively to autonomic and respiratory nuclei in the brainstem and spinal cord and help regulate homeostatic function. Previously, abnormalities in 5-HT receptor binding in the medullae of infants dying from sudden infant death syndrome (SIDS) were identified, suggesting that medullary 5-HT dysfunction may be responsible for a subset of SIDS cases. To investigate cellular defects associated with altered 5-HT receptor binding in the 5-HT pathways of the medulla in SIDS cases. Frozen medullae from infants dying from SIDS (cases) or from causes other than SIDS (controls) were obtained from the San Diego Medical Examiner's office between 1997 and 2005. Markers of 5-HT function were compared between SIDS cases and controls, adjusted for postconceptional age and postmortem interval. The number of samples available for each analysis ranged from 16 to 31 for SIDS cases and 6 to 10 for controls. An exploratory analysis of the correlation between markers and 6 recognized risk factors for SIDS was performed. 5-HT neuron count and density, 5-HT(1A) receptor binding density, and 5-HT transporter (5-HTT) binding density in the medullary 5-HT system; correlation between these markers and 6 recognized risk factors for SIDS. Compared with controls, SIDS cases had a significantly higher 5-HT neuron count (mean [SD], 148.04 [51.96] vs 72.56 [52.36] cells, respectively; P<.001) and 5-HT neuron density (P<.001), as well as a significantly lower density of 5-HT(1A) receptor binding sites (P

  10. The clinical analysis of bilateral successive sudden sensorineural hearing loss.

    Science.gov (United States)

    Wang, Yaowen; Zhang, Litao; Zhang, Jianhua; Zhang, Xuqun; Zhang, Weimin; Chen, Xing; Tang, Shixiong

    2016-11-01

    The objective of this study is to investigate the clinical characteristics of successive bilateral sudden sensorineural hearing loss (SSNHL) with an interval of more than 1 year to aid the evaluation and management of successive bilateral SSNHL (BSSNHL). 14 successive BSSNHL patients and 118 unilateral SSNHL patients with severe and profound hearing loss were reviewed retrospectively. Information about successive BSSNHL was collected included demographics, the intervals between the attacks of bilateral ears, the past medical history, inducing factors, accompanying symptoms, pure-tone tests, blood tests, b-ultrasound examinations of vertebral artery and carotid artery, and medical interventions. And the comparison of improvement rate was made between successive BSSNHL and unilateral SSNHL. SPSS 15.0 was used to analyze the data. In successive BSSNHL, there were six males and eight females; the average aged was 49.86 ± 15.45 years (20-73 years). The interval of the two attacks was 11.43 ± 12.07 years (1-50 years) on average. The onset of treatment was 18.86 ± 12.71 days. Tinnitus was seen in 100 % of the patients, followed by vertigo in 42.85 %, and ear fullness in 21.43 %. 3 of 14 patients described obvious inducing factor: tiredness. Five patients (35.71 %) had hypertension histories, three (21.43 %) had diabetes histories, two (14.29 %) had surgery histories, one (7.14 %) was with depression history, one (7.14 %) was with coronary heart disease history. 30 % (3/10) patients were with atherosclerotic plaque in carotid artery. 4 (28.57 %) patients were with high blood sugar. 8 patients (57.14 %) were with high blood lipids. Thyroid function tests were positive in 27.27 % (3/11) patients. No abnormality was found in antinuclear antibodies titer. The percentage of profound and severe hearing loss were 71.43 and 78.57 % in the recently affected ear and contralateral ear separately. The PTAs of the recently affected ear were 77.14 ± 27.12

  11. Survival advantage from ventricular fibrillation and pulseless electrical activity in women compared to men: the Oregon Sudden Unexpected Death Study.

    Science.gov (United States)

    Teodorescu, Carmen; Reinier, Kyndaron; Uy-Evanado, Audrey; Ayala, Jo; Mariani, Ronald; Wittwer, Lynn; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S

    2012-09-01

    Studies evaluating a possible survival advantage from sudden cardiac arrest (SCA) in women have produced mixed results possibly due to a lack of comprehensive analyses. We hypothesized that race, socioeconomic status (SES), and elements of the lifetime clinical history influence gender effects and need to be incorporated within analyses of survival. Cases of SCA were identified from the ongoing, prospective, multiple-source Oregon Sudden Unexpected Death Study (population approximately one million). Subjects included were age ≥18 years who underwent attempted resuscitation by EMS providers. Pearson's chi-square tests and independent samples t tests or analysis of variance were used for univariate comparisons. We evaluated gender and race differences in survival adjusted for age, circumstances of arrest, disease burden, and socioeconomic status using a logistic regression model predicting survival. A total of 1,296 cases had resuscitation attempted (2002-2007; mean age 65 years, male 67%). Women were older than men (68 vs. 63 years, p ratio 1.85; 95% confidence interval (1.12-3.04)]. Despite older age, higher prevalence of SCA in the home, and higher rates of PEA, women had a survival advantage from ventricular fibrillation and pulseless electrical activity.

  12. Law enforcement duties and sudden cardiac death among police officers in United States: case distribution study.

    Science.gov (United States)

    Varvarigou, Vasileia; Farioli, Andrea; Korre, Maria; Sato, Sho; Dahabreh, Issa J; Kales, Stefanos N

    2014-11-18

    To assess the association between risk of sudden cardiac death and stressful law enforcement duties compared with routine/non-emergency duties. Case distribution study (case series with survey information on referent exposures). United States law enforcement. Summaries of deaths of over 4500 US police officers provided by the National Law Enforcement Officers Memorial Fund and the Officer Down Memorial Page from 1984 to 2010. Observed and expected sudden cardiac death counts and relative risks for sudden cardiac death events during specific strenuous duties versus routine/non-emergency activities. Independent estimates of the proportion of time that police officers spend across various law enforcement duties obtained from surveys of police chiefs and front line officers. Impact of varying exposure assessments, covariates, and missing cases in sensitivity and stability analyses. 441 sudden cardiac deaths were observed during the study period. Sudden cardiac death was associated with restraints/altercations (25%, n=108), physical training (20%, n=88), pursuits of suspects (12%, n=53), medical/rescue operations (8%, n=34), routine duties (23%, n=101), and other activities (11%, n=57). Compared with routine/non-emergency activities, the risk of sudden cardiac death was 34-69 times higher during restraints/altercations, 32-51 times higher during pursuits, 20-23 times higher during physical training, and 6-9 times higher during medical/rescue operations. Results were robust to all sensitivity and stability analyses. Stressful law enforcement duties are associated with a risk of sudden cardiac death that is markedly higher than the risk during routine/non-emergency duties. Restraints/altercations and pursuits are associated with the greatest risk. Our findings have public health implications and suggest that primary and secondary cardiovascular prevention efforts are needed among law enforcement officers. © Varvarigou et al 2014.

  13. Sudden gains in cognitive-behavior therapy for treatment-resistant depression: Processes of change.

    Science.gov (United States)

    Abel, Anna; Hayes, Adele M; Henley, William; Kuyken, Willem

    2016-08-01

    Sudden gains were investigated in cognitive-behavioral therapy (CBT) for treatment-resistant depression (TRD). Client and therapist processes in sessions proximal to sudden gains were examined to better understand the antecedents of sudden gains and potential mechanisms linking them to outcome. Participants were 156 adults with TRD in a randomized controlled trial of CBT as an adjunct to pharmacotherapy (Wiles et al., 2013). Depression symptoms were assessed by the Beck Depression Inventory-II at each session. In a subsample of 50 clients, audio-recordings of 125 therapy sessions were rated for hope, emotional processing, and therapist competence in case-conceptualization. Sudden gains were experienced by 54% of participants. Those with gains reported significantly lower depression severity at 12-month follow-up and more remission of symptoms than those without gains. Sudden gains also predicted lower depression at follow-up, beyond the slope of linear change in symptoms across treatment. Therapists demonstrated greater competence in case conceptualization with clients who reported sudden gains, and those with gains expressed more hope in sessions prior to a gain. In addition, more hope and emotional processing in the pregain sessions predicted less depression at follow-up, controlling for depression scores in the prior session. Better therapist conceptualization skills and more client hope in the baseline and pregain sessions were also associated with more emotional processing in those same sessions. This study extends the phenomenon of sudden gains in CBT for depression to a treatment-resistant population and identified important therapy processes that predicted long-term outcomes: hope and emotional processing. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  14. The significance of routine laboratory parameters in patients with sudden sensorineural hearing loss.

    Science.gov (United States)

    Yasan, Hasan; Tüz, Mustafa; Yariktaş, Murat; Aynali, Giray; Tomruk, Onder; Akkuş, Omer

    2013-12-01

    There are several factors (viral infections, metabolic and ototoxic disorders etc.) accused for the development of sudden sensorineural hearing loss. Some prognostic factors (late onset of treatment etc.) had been evaluated in the literature. There is no sufficient data on the effect of routine laboratory parameters on the development and/or prognosis of sudden sensorineural hearing loss. The aim of this study is to investigate the effects of routine blood chemistry and hematological parameters on the development and prognosis of disease in patients with idiopathic sudden sensorineural hearing loss. One hundred and forty-seven patients with the diagnosis of idiopathic sudden sensorineural hearing loss followed up during the periods of 2000-2010 years were included in this study. One hundred and three septoplasty patients with no otologic complaints were enrolled as control group. Following the clinical and demographic evaluations, patients with idiopathic sudden sensorineural hearing loss and control groups, and patients treated successfully and patients with poor outcome were compared with each other. Data were analyzed by T test. All hematological and biochemical parameters were compared. Hemoglobin, hematocrit, white blood cell count, total and direct bilirubin, fasting blood glucose level and aspartate aminotransferase were significantly different between idiopathic sudden sensorineural hearing loss and control groups. There was no significantly different parameter between patients treated successfully and patients with poor outcome. Hemoglobin, hematocrit, white blood cell count, total and direct bilirubin, fasting blood glucose level and AST all can be risk factors for SHL, or they can be the result of undetermined pathology, because these parameters have no effect on the prognosis. Other routine parameters seem to have no effect on the development and/or prognosis of idiopathic sudden sensorineural hearing loss.

  15. Sudden cardiac death in athletes and its preventive strategies: review article

    Directory of Open Access Journals (Sweden)

    Farzin Halabchi

    2017-12-01

    Full Text Available Sudden cardiac death in sport, although rare, but is a tragic event, attracting the media and public attention. Sport and exercise may act as a trigger for sudden cardiac death. Risk of sudden death in young athletes with cardiovascular disease is 2.5 times more frequent than non-athlete individuals. More than 90% of cases of sudden death occur during or immediately after training or competition. Incidence of sudden cardiac death in any population, including athletes, is related to multiple factors such as gender, age, race, nationality, diagnostic screening methods and preventive measures for sudden cardiac death. Otherwise, incidence rate of sudden cardiac death is linked to the used definition and method of diagnosis. Different cardiovascular disorders may result in death of young athletes and hypertrophic cardiomyopathy, congenital coronary anomalies, arrhythmogenic right ventricular dysplasia and aortic rupture are among the most common causes. Marfan syndrome, dilated cardiomyopathy, viral myocarditis, Wolff-Parkinson-White (WPW syndrome, congenital long QT syndrome, Brugada syndrome and commotio cordis are reported as other etiologies. In older athletes (more than 35 years, ischemic coronary heart disease is responsible for majority of the cases similar to the general population. Because the outcome of sudden cardiac arrest in sports is very poor except in few cases, proper national strategies are needed to diminish the burden of sudden death in young athletes. It seems that there are two main strategies to achieve this goal: A Primary prevention with use of purposeful pre-participation evaluation programs. This evaluation should focuss on the proper history and physical examination. Nevertheless, there is significant debate between American and European countries regarding the use of paraclinical investigations (especially ECG. American heart association does not recommend ECG as an essential part of evaluation. In contrast, European

  16. Cardiomyopathies as a Cause of Sudden Cardiac Death (SCD in Egypt: Recognition and Preventive Strategies Needed

    Directory of Open Access Journals (Sweden)

    Nora Fnon

    2016-06-01

    Full Text Available This study aimed at evaluating the epidemiological characteristics and pathological features of different types of cardiomyopathies in Egypt, highlighting the role of the forensic pathologist in identifying cases of cardiomyopathies and initiating for their families a possible genetic study aiming at prevention of sudden death. All cases with sudden cardiac death (SCD due to cardiomyopathies during the period from the beginning of January 2010 until the end of December 2014 (5 years were included in this study. All hearts underwent detailed gross and histological examination. Circumstances of death, medical history, and post-mortem pathological findings were thoroughly  investigated. Out of 535 cases of sudden cardiac death, there were 22 cases (4.1% diagnosed as having cardiomyopathies; sudden death was their first presentation. Eighteen cases (81.8% were male, with the 4th decade (11 cases, 50% being the most affected age; severe physical activity and exertion were evident in death circumstances of 14 cases (63.6%; pathological evaluation revealed that hypertrophic cardiomyopathy was the most frequent type, being diagnosed in 10 cases (45%. Cardiomyopathies are an infrequent cause of sudden cardiac death. Most deaths are in children and adults, so cases are of high social impact that demands multidisciplinary research and resources. In all cases of SCD, forensic autopsy should be done. Forensic study is the key to identifying an affected family and the starting point regarding assessing them.

  17. Impact of mean platelet volume on the occurrence and severity of sudden sensorineural hearing loss.

    Science.gov (United States)

    Sagit, M; Kavugudurmaz, M; Guler, S; Somdas, M A

    2013-10-01

    We aimed to determine: (1) whether mean platelet volume was elevated in patients with sudden sensorineural hearing loss, compared with healthy controls; and (2) whether mean platelet volume level was related to hearing loss severity. The study included 31 patients with sudden sensorineural hearing loss and 31 age- and sex-matched, healthy controls. Peripheral venous blood samples were taken from subjects and mean platelet volume and levels of glucose, total cholesterol, high-density lipoprotein, low-density lipoprotein and triglyceride were measured. Mean platelet volume was significantly greater in the sudden sensorineural hearing loss group compared with the control group. However, there was no significant correlation between mean platelet volume level and hearing loss severity. Mean platelet volume, a determinant of platelet activation, is elevated in patients with sudden sensorineural hearing loss. To our knowledge, this is the first report investigating mean platelet volume levels in such patients. Our findings indirectly support the hypothesis of vascular impairment as a pathogenetic factor in sudden sensorineural hearing loss.

  18. Catatonia Secondary to Sudden Clozapine Withdrawal: A Case with Three Repeated Episodes and a Literature Review

    Directory of Open Access Journals (Sweden)

    John Bilbily

    2017-01-01

    Full Text Available A literature search identified 9 previously published cases that were considered as possible cases of catatonia secondary to sudden clozapine withdrawal. Two of these 9 cases did not provide enough information to make a diagnosis of catatonia according to the Diagnostic and Statistical Manual, 5th Edition (DSM-5. The Liverpool Adverse Drug Reaction (ADR Causality Scale was modified to assess ADRs secondary to drug withdrawal. From the 7 published cases which met DSM-5 catatonia criteria, using the modified scale, we established that 3 were definitive and 4 were probable cases of catatonia secondary to clozapine withdrawal. A new definitive case is described with three catatonic episodes which (1 occurred after sudden discontinuation of clozapine in the context of decades of follow-up, (2 had ≥3 of 12 DSM-5 catatonic symptoms and serum creatinine kinase elevation, and (3 required medical hospitalization and intravenous fluids. Clozapine may be a gamma-aminobutyric acid (GABA receptor agonist; sudden clozapine withdrawal may explain a sudden decrease in GABA activity that may contribute to the development of catatonic symptoms in vulnerable patients. Based on the limited information from these cases, the pharmacological treatment for catatonia secondary to sudden clozapine withdrawal can include benzodiazepines and/or restarting clozapine.

  19. [Clinical features of sudden sensorineural hearing loss accompanied with inner ear hemorrhage].

    Science.gov (United States)

    Chen, Xihang; Lin, Chang; Fang, Zheming; Chen, Xi; Ye, Shengnan; Cheng, Jinmei; Zhang, Rong

    2015-12-01

    To investigate the clinical features, diagnosis and prognosis of sudden sensorineural hearing loss accompanied with inner ear hemorrhage. Eleven cases of sudden sensorineural hearing loss accompanied with inner ear hemorrhage were retrospectively analyzed, including clinical manifestation, hematological and audiological examinations, as well as characteristics of inner ear three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). Eleven cases of sudden hearing loss with inner ear hemorrhage were accompanied by varying degrees of vertigo, lasting from several minutes to several hours, nine of whom had persistent tinnitus. The audiometry curves of the 11 cases included total deafness or flat descending type. The inner ear 3D-FLAIR MRI studies revealed abnormal high signals at different positions of the inner ear, one case with endolymphatic hydrops. After the treatment, seven cases were invalid, two cases had notable effect, and two cases were effective. Abnormal high signals in the inner ear were sensitively detected by 3D-FLAIR MRI sequence, which was applied for the diagnosis of the sudden hearing loss accompanied with inner ear hemorrhage. The effect of conventional treatment was not good and the appropriate treatments for this type of sudden hearing loss need further investigation.

  20. Parkinson’s Disease Differentially Affects Adaptation to Gradual as Compared to Sudden Visuomotor Distortions

    Science.gov (United States)

    Venkatakrishnan, Anusha; Banquet, Jean P.; Burnod, Yves; Contreras-Vidal, José L.

    2011-01-01

    Patients with Parkinson’s disease (PD) have difficulties in movement adaptation to optimize performance in novel environmental contexts such as altered screen cursor-hand relationships. Prior studies have shown that the time course of the distortion differentially affects visuomotor adaptation to screen cursor rotations, suggesting separate mechanisms for gradual and sudden adaptation. Moreover, studies in human and non-human primates suggest that adaptation to sudden kinematic distortions may engage the basal ganglia, whereas adaptation to gradual kinematic distortions involves cerebellar structures. In the present studies, participants were patients with PD, who performed center-out pointing movements, using either a digitizer tablet and pen or a computer trackball, under normal or rotated screen cursor feedback conditions. The initial study tested patients with PD using a cross-over experimental design for adaptation to gradual as compared with sudden rotated hand-screen cursor relationships and revealed significant after-effects for the gradual adaptation task only. Consistent with these results, findings from a follow-up experiment using a trackball that required only small finger movements showed that patients with PD adapt better to gradual as against sudden perturbations, when compared to age-matched healthy controls. We conclude that Parkinson’s disease affects adaptation to sudden visuomotor distortions but spares adaptation to gradual distortions. PMID:21414678

  1. 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)

  2. Aspen, climate, and sudden decline in western USA

    Science.gov (United States)

    Gerald E. Rehfeldt; Dennis E. Ferguson; Nicholas L. Crookston

    2009-01-01

    A bioclimate model predicting the presence or absence of aspen, Populus tremuloides, in western USA from climate variables was developed by using the Random Forests classification tree on Forest Inventory data from about 118,000 permanent sample plots. A reasonably parsimonious model used eight predictors to describe aspen's climate profile. Classification errors...

  3. Sudden death associated with group A streptococcal infection in an 8-year-old girl with undiagnosed hypertrophic cardiomyopathy.

    OpenAIRE

    Bragonier, R.; Oades, P.

    1998-01-01

    An 8-year-old girl died suddenly without prior symptoms. Post-mortem examination identified both systemic group A streptococcal infection and hypertrophic cardiomyopathy. She had no history of cardiac symptoms and was not in a high-risk group for sudden death due to hypertrophic cardiomyopathy. We believe the disseminated but asymptomatic group A streptococcal infection precipitated her early death from hypertrophic cardiomyopathy. Sudden unexpected death during systemic infection should be f...

  4. Chemical and Dynamical Impacts of Stratospheric Sudden Warmings on Arctic Ozone Variability

    Science.gov (United States)

    Strahan, S. E.; Douglass, A. R.; Steenrod, S. D.

    2016-01-01

    We use the Global Modeling Initiative (GMI) chemistry and transport model with Modern-Era Retrospective Analysis for Research and Applications (MERRA) meteorological fields to quantify heterogeneous chemical ozone loss in Arctic winters 2005-2015. Comparisons to Aura Microwave Limb Sounder N2O and O3 observations show the GMI simulation credibly represents the transport processes and net heterogeneous chemical loss necessary to simulate Arctic ozone. We find that the maximum seasonal ozone depletion varies linearly with the number of cold days and with wave driving (eddy heat flux) calculated from MERRA fields. We use this relationship and MERRA temperatures to estimate seasonal ozone loss from 1993 to 2004 when inorganic chlorine levels were in the same range as during the Aura period. Using these loss estimates and the observed March mean 63-90N column O3, we quantify the sensitivity of the ozone dynamical resupply to wave driving, separating it from the sensitivity of ozone depletion to wave driving. The results show that about 2/3 of the deviation of the observed March Arctic O3 from an assumed climatological mean is due to variations in O3 resupply and 13 is due to depletion. Winters with a stratospheric sudden warming (SSW) before mid-February have about 1/3 the depletion of winters without one and export less depletion to the midlatitudes. However, a larger effect on the spring midlatitude ozone comes from dynamical differences between warm and cold Arctic winters, which can mask or add to the impact of exported depletion.

  5. Stratification of the Risk of Sudden Death in Nonischemic Heart Failure

    Directory of Open Access Journals (Sweden)

    Maurício Pimentel

    2014-10-01

    Full Text Available Despite significant therapeutic advancements, heart failure remains a highly prevalent clinical condition associated with significant morbidity and mortality. In 30%-40% patients, the etiology of heart failure is nonischemic. The implantable cardioverter-defibrillator (ICD is capable of preventing sudden death and decreasing total mortality in patients with nonischemic heart failure. However, a significant number of patients receiving ICD do not receive any kind of therapy during follow-up. Moreover, considering the situation in Brazil and several other countries, ICD cannot be implanted in all patients with nonischemic heart failure. Therefore, there is an urgent need to identify patients at an increased risk of sudden death because these would benefit more than patients at a lower risk, despite the presence of heart failure in both risk groups. In this study, the authors review the primary available methods for the stratification of the risk of sudden death in patients with nonischemic heart failure.

  6. Bilateral sudden sensorineural hearing loss as a presenting feature of systemic lupus erythematosus

    Science.gov (United States)

    Chawki, Sylvain; Aouizerate, Jessie; Trad, Selim; Prinseau, Jacques; Hanslik, Thomas

    2016-01-01

    Abstract Introduction: Sudden sensorineural hearing loss is an unusual presenting clinical feature of systemic lupus erythematosus. Case report: We report the case of a young woman who was admitted to hospital for sudden sensorineural hearing loss and hemophagocytic syndrome which was attributed to systemic lupus erythematosus on the basis of specific renal involvement, thrombocytopenia, and consistent autoantibodies. Favorable outcome was obtained on high-dose corticosteroids, and the hearing fully recovered. Discussion: Sudden sensorineural hearing loss in systemic lupus erythematosus is seemingly more frequently associated with severe systemic involvement and antiphospholipid antibodies may be present. Although management remains empirical, the high risk of permanent hearing impairment seems to justify emergency treatment with high-dose corticosteroids. When the clinical and laboratory criteria of antiphospholipid syndrome are met, antiplatelets agents or anticoagulation therapy shall be considered. PMID:27603334

  7. Heart diseases play a vital role in sudden unexpected death in epilepsy

    Directory of Open Access Journals (Sweden)

    Ze-ning SHI

    2014-12-01

    Full Text Available Sudden unexpected death in epilepsy (SUDEP indicates sudden death without a definite cause in epileptics, especially during seizures or interictal phase. The risk of sudden death in epileptic patients is over 20 times higher than that in individuals without epilepsy. The explicit pathogenesis of SUDEP is not clear, while the heart disease is likely to play an important role in SUDEP. Cardiac dysfunction, which is caused by ion channel diseases, autonomic dysfunction, antiepileptic drugs (AEDs, is associated with SUDEP. Understanding of the mechanisms about cardiac factors is required to provide effective strategy for future control of SUDEP. doi: 10.3969/j.issn.1672-6731.2014.11.006

  8. Tissue specific responses alter the biomass accumulation in wheat under gradual and sudden salt stress

    Directory of Open Access Journals (Sweden)

    Yumurtaci A.

    2012-11-01

    Full Text Available Salinity is one the major limiting environmental factors which has negative side effects on crop production. The purpose of this study was to investigate the differences between the gradual and sudden salt stress effects on biomass accumulation associated with whole plant development in three different tissues of two wheat species ( Triticum aestivum and Triticum durum under hydroponic conditions in the long term. Considering the effects of sudden and gradual stress for biomass accumulation, while importance of salinity x genotype interaction for fresh weights was 5%, association for salinity x tissue type was found as 1% important. Interestingly, root branching and development of lateral roots were much more negatively affected by gradual stress rather than sudden salt application. Our results demonstrated that root and leaf were both critical tissues to test the salt tolerance by physiologically but sheath tissue might be used as an alternative source of variation for solving the interactions between root and leaves in wheat.

  9. Massive parallel sequencing applied to the molecular autopsy in sudden cardiac death in the young.

    Science.gov (United States)

    Brion, M; Sobrino, B; Martinez, M; Blanco-Verea, A; Carracedo, A

    2015-09-01

    Sudden cardiac death in the young is a very traumatic event that occurs often in apparently healthy individuals without an explainable cause of death after a comprehensive medico-legal investigation. Knowledge about the pathologies with a risk of sudden death is increasingly showing a greater underlying genetic heterogeneity, which provides one of the main handicaps for molecular autopsy. On the other hand the enormous technological advances in sequencing technologies, allow us to analyse as many genes as we want at a cost increasingly reduced. The sum of these two factors (increased knowledge of genetics and available technologies) allow us to make an individualized study of the causes of sudden cardiac death in young adults, through massive sequencing of all potential genes involved in the process. We define this approach as massive genomic autopsy, and with this review we will try to explain the possible scenarios and methods available for its implementation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Prognostic factors for idiopathic sudden sensorineural hearing loss treated with hyperbaric oxygen therapy and intravenous steroids.

    Science.gov (United States)

    Hosokawa, S; Sugiyama, K; Takahashi, G; Takebayashi, S; Mineta, H

    2017-01-01

    This study evaluated the prognosis of idiopathic sudden sensorineural hearing loss when treated with hyperbaric oxygen therapy and intravenous steroids. The clinical data for 334 patients with idiopathic sudden sensorineural hearing loss treated by hyperbaric oxygen therapy and intravenous steroids at our hospital were retrospectively reviewed. These data included the initial averaged five-frequency hearing level, patient age, interval between onset of symptoms and treatment, vertigo as a complication, and co-existence of diabetes mellitus. The overall improvement rate was 69.2 per cent, including better improvement (25.5 per cent), good improvement (21.0 per cent) and fair improvement (22.7 per cent). Hyperbaric oxygen therapy appears to confer a significant additional therapeutic benefit when used in combination with steroid therapy for idiopathic sudden sensorineural hearing loss. If performed early, hyperbaric oxygen therapy may bring about hearing improvement in many patients who are unresponsive to initial therapy.

  11. Constraint-induced sound therapy for sudden sensorineural hearing loss--behavioral and neurophysiological outcomes.

    Science.gov (United States)

    Okamoto, Hidehiko; Fukushima, Munehisa; Teismann, Henning; Lagemann, Lothar; Kitahara, Tadashi; Inohara, Hidenori; Kakigi, Ryusuke; Pantev, Christo

    2014-01-29

    Sudden sensorineural hearing loss is characterized by acute, idiopathic hearing deterioration. We report here the development and evaluation of "constraint-induced sound therapy", which is based on a well-established neuro-rehabilitation approach, and which is characterized by the plugging of the intact ear ("constraint") and the simultaneous, extensive stimulation of the affected ear with music. The sudden sensorineural hearing loss patients who received the constraint-induced sound therapy in addition to the standard corticosteroid therapy showed significantly better recovery of hearing function compared to those who had only received corticosteroid treatments. Additionally, the brain activity obtained in a subgroup of patients suggested that the constraint-induced sound therapy could have prevented maladaptive auditory cortex reorganization. Constraint-induced sound therapy thus appears to be an effective, practical, and safe treatment option for sudden sensorineural hearing loss.

  12. Constraint-induced sound therapy for sudden sensorineural hearing loss – behavioral and neurophysiological outcomes

    Science.gov (United States)

    Okamoto, Hidehiko; Fukushima, Munehisa; Teismann, Henning; Lagemann, Lothar; Kitahara, Tadashi; Inohara, Hidenori; Kakigi, Ryusuke; Pantev, Christo

    2014-01-01

    Sudden sensorineural hearing loss is characterized by acute, idiopathic hearing deterioration. We report here the development and evaluation of “constraint-induced sound therapy”, which is based on a well-established neuro-rehabilitation approach, and which is characterized by the plugging of the intact ear (“constraint”) and the simultaneous, extensive stimulation of the affected ear with music. The sudden sensorineural hearing loss patients who received the constraint-induced sound therapy in addition to the standard corticosteroid therapy showed significantly better recovery of hearing function compared to those who had only received corticosteroid treatments. Additionally, the brain activity obtained in a subgroup of patients suggested that the constraint-induced sound therapy could have prevented maladaptive auditory cortex reorganization. Constraint-induced sound therapy thus appears to be an effective, practical, and safe treatment option for sudden sensorineural hearing loss. PMID:24473277

  13. Evaluation of effectiveness of stellate ganglion block (SGB) treatment of sudden hearing loss.

    Science.gov (United States)

    Takinami, Yoshikazu

    2012-01-01

    A stellate ganglion block (SGB) based on the goal of improving internal ear circulatory disturbance appears to be beneficial for the treatment of sudden hearing loss. To evaluate the effectiveness of SGB for sudden hearing loss. This retrospective study reviewed the medical records of 49 patients who received SGBs and 496 patients who received only conservative therapy, primarily with systemic steroids, for treatment of sudden hearing loss. Propensity scores were used in pairwise matching of these patients to avoid selection biases between the two treatment modalities. Propensity score matching yielded 48 pairs. The mean therapeutic effect of the SGB was calculated to be 0.40 ± 0.20 (mean ± standard error, p = 0.051).

  14. Ethics of Placebo Control in Trials for Idiopathic Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Maldonado Fernández, Miguel; Kornetsky, Susan; Rubio Rodriguez, Laura

    2016-07-01

    Idiopathic sudden sensorineural hearing loss (ISSHL) involves sudden loss of hearing from cochlear or retrocochlear origin of unknown cause. Systemic corticosteroids may be considered in the management of ISSNHL. However, an updated Cochrane systematic review concludes that "the value of steroids in the treatment of idiopathic sudden sensorineural hearing loss remains unclear since the evidence obtained from randomized controlled trials is contradictory in outcome." Therefore, a new clinical trial that addresses this question is mandatory. A first step in its design is to determine if placebo control would be ethically acceptable. We conclude that there is equipoise (uncertainty) about the use of corticosteroids for ISSHL. A new trial is justified-but with the inclusion of interim analyses to detect early imbalances on efficacy or safety and with the ability to stop the trial if needed. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  15. Long Bubble Penetration through Viscoelastic Fluids in a Suddenly Contracting and Expanding Tube

    Directory of Open Access Journals (Sweden)

    Ching-Chuan Chang

    2016-01-01

    Full Text Available This study investigated the properties of long bubbles penetrating viscoelastic fluids in a suddenly contracting and expanding tube. Injection gas flow is controlled by a mass flow controller (MFC. Some of dimensionless parameters, such as the capillary number (Ca, the Reynolds number (Re, the fractional ratio (m, and the Weissenberg number (Wi, are discussed herein. The experimental results showed that bubble velocity, Ca, and Wi increase as shear viscosity increases under a constant gas flow by MFC. However, as shear viscosity increases, bubble diameter decreases, and m increases. When gas flow is 200 mL/min and shear viscosity increases, the bubble front is sharper in the contraction tube, and the bubble front shape is blunter in the sudden expansion tube. When gas flow is 600 mL/min and shear viscosity increases, the bubble front is blunter in the contraction tube and exhibits a torch shape in the sudden expansion tube.

  16. Sudden Cardiac Arrest due to Brugada Syndrome: a Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    R Soleimanirad

    2013-04-01

    Full Text Available Brugada Syndrome is a rare cause of sudden cardiac arrest and has a unique ECG pattern. In fact, with ST-segment elevation down sloping in the right precordial leads (v1-v3, RBBB pattern in lateral leads and J-point elevation is revealed. We must notice and avoid trigger factors of this syndrome during general anesthesia. Patient is a 39 old man who attended to emergency department with sudden cardiac arrest and resuscitate. He was transferred to ICU for management of hypoxic ischemic encephalopathy. Complementary studies concluded the diagnosis of Brugada syndrome. We must consider Brugada syndrome within patients with family history of sudden cardiac arrest. Moreover, we must avoid trigger factors of this syndrome such as fever, bradicardia and electrolyte abnormality (specialy Na, Ca abnormalities during general anesthesia and if they appear, we should treat them.

  17. Transient tropospheric electric fields resulting from sudden changes in ionospheric conductivity

    Science.gov (United States)

    Dejnakarintra, M.; Inan, U. S.; Carpenter, D. L.

    1985-01-01

    Electric field mapping in the earth's atmosphere has been a research subject for more than 20 years. The present paper is concerned with the downward mapping of an ionospheric electric field into the troposphere following a 'sudden' - change in the atmospheric conductivity profile. The formulation is limited to the case of a static magnetic field which is vertical to the earth's surface. The obtained results are, therefore, most applicable at high latitudes. It is assumed that the 'sudden' change occurs within a fraction of a second and is sustained for a time of the order of at least several seconds. It is pointed out that such changes in ionospheric conductivity can occur as a result of sudden solar particle events (SPE) or particle precipitation into the lower ionosphere. Attention is given to theory, electric field calculations, and the obtained results.

  18. Sudden headache, third nerve palsy and visual deficit: thinking outside the subarachnoid haemorrhage box.

    Science.gov (United States)

    Ní Chróinín, Danielle; Lambert, John

    2013-11-01

    A 75-year-old lady presented with sudden severe headache and vomiting. Examination was normal, and CT and lumbar puncture not convincing for subarachnoid haemorrhage. Shortly thereafter, she developed painless diplopia. Examination confirmed right third cranial nerve palsy plus homonymous left inferior quadrantanopia. Urgent cerebral MRI with angiography was requested to assess for a possible posterior communicating artery aneurysm, but revealed an unsuspected pituitary mass. Pituitary adenoma with pituitary apoplexy was diagnosed. Pituitary apopolexy is a syndrome comprising sudden headache, meningism, visual and/or oculomotor deficits, with an intrasellar mass. It is commonly due to haemorrhage or infarction within a pituitary adenoma. Treatment includes prompt steroid administration, and potentially surgical decompression. While subarachnoid haemorrhage is an important, well-recognised cause of sudden severe headache, other aetiologies, including pituitary apoplexy, should be considered and sought.

  19. 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......A slower reflex response to sudden trunk loading (SL) has been shown to increase future risk of low back injuries in healthy subjects, and specific readiness training can improve the response to SL among healthy subjects. The purpose of the study was to investigate the effect of recreational soccer...... the reflex response to SL. The faster reflex response indicates that soccer training can reduce the risk of low back injuries....

  20. Genetic mutation in Korean patients of sudden cardiac arrest as a surrogating marker of idiopathic ventricular arrhythmia.

    Science.gov (United States)

    Son, Myoung Kyun; Ki, Chang-Seok; Park, Seung-Jung; Huh, June; Kim, June Soo; On, Young Keun

    2013-07-01

    Mutation or common intronic variants in cardiac ion channel genes have been suggested to be associated with sudden cardiac death caused by idiopathic ventricular tachyarrhythmia. This study aimed to find mutations in cardiac ion channel genes of Korean sudden cardiac arrest patients with structurally normal heart and to verify association between common genetic variation in cardiac ion channel and sudden cardiac arrest by idiopathic ventricular tachyarrhythmia in Koreans. Study participants were Korean survivors of sudden cardiac arrest caused by idiopathic ventricular tachycardia or fibrillation. All coding exons of the SCN5A, KCNQ1, and KCNH2 genes were analyzed by Sanger sequencing. Fifteen survivors of sudden cardiac arrest were included. Three male patients had mutations in SCN5A gene and none in KCNQ1 and KCNH2 genes. Intronic variant (rs2283222) in KCNQ1 gene showed significant association with sudden cardiac arrest (OR 4.05). Four male sudden cardiac arrest survivors had intronic variant (rs11720524) in SCN5A gene. None of female survivors of sudden cardiac arrest had SCN5A gene mutations despite similar frequencies of intronic variants between males and females in 55 normal controls. Common intronic variant in KCNQ1 gene is associated with sudden cardiac arrest caused by idiopathic ventricular tachyarrhythmia in Koreans.

  1. Fatty acid oxidation disorders as primary cause of sudden and unexpected death in infants and young children

    DEFF Research Database (Denmark)

    Banner, Jytte; Kølvraa, S; Gregersen, N

    1997-01-01

    Disorders of fatty acid metabolism are known to be responsible for cases of sudden and unexpected death in infancy. At least 14 disorders are known at present. 120 cases of sudden infant death syndrome (SIDS) had been examined for a prevalent mutation (G985) causing medium chain acyl CoA dehydrog......Disorders of fatty acid metabolism are known to be responsible for cases of sudden and unexpected death in infancy. At least 14 disorders are known at present. 120 cases of sudden infant death syndrome (SIDS) had been examined for a prevalent mutation (G985) causing medium chain acyl Co...

  2. Ependymal alterations in sudden intrauterine unexplained death and sudden infant death syndrome: possible primary consequence of prenatal exposure to cigarette smoking

    Directory of Open Access Journals (Sweden)

    Matturri Luigi

    2010-07-01

    Full Text Available Abstract Background The ependyma, the lining providing a protective barrier and filtration system separating brain parenchyma from cerebrospinal fluid, is still inadequately understood in humans. In this study we aimed to define, by morphological and immunohistochemical methods, the sequence of developmental steps of the human ependyma in the brainstem (ventricular ependyma and thoracic spinal cord (central canal ependyma of a large sample of fetal and infant death victims, aged from 17 gestational weeks to 8 postnatal months. Additionally, we investigated a possible link between alterations of this structure, sudden unexplained fetal and infant death and maternal smoking. Results Our results demonstrate that in early fetal life the human ependyma shows a pseudostratified cytoarchitecture including many tanycytes and ciliated cells together with numerous apoptotic and reactive astrocytes in the subependymal layer. The ependyma is fully differentiated, with a monolayer of uniform cells, after 32 to 34 gestational weeks. We observed a wide spectrum of ependymal pathological changes in sudden death victims, such as desquamation, clusters of ependymal cells in the subventricular zone, radial glial cells, and the unusual presence of neurons within and over the ependymal lining. These alterations were significantly related to maternal smoking in pregnancy. Conclusions We conclude that in smoking mothers, nicotine and its derivatives easily reach the cerebrospinal fluid in the fetus, immediately causing ependymal damage. Consequently, we suggest that the ependyma should be examined in-depth first in victims of sudden fetal or infant death with mothers who smoke.

  3. Definition of Sudden Infant Death and Sudden Intrauterine Unexpected Death Syndromes (SIDS and SIUDS with Regard to the Anatomo-Pathological Examination

    Directory of Open Access Journals (Sweden)

    Giulia Ottaviani

    2016-09-01

    Full Text Available 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 six-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 will become necessary.

  4. Contrast-enhanced MR imaging of the endolymphatic sac in patients with sudden hearing loss

    Energy Technology Data Exchange (ETDEWEB)

    Naganawa, Shinji; Koshikawa, Tokiko; Fukatsu, Hiroshi; Ishigaki, Takeo [Department of Radiology, Nagoya University School of Medicine (Japan); Nakashima, Tsutomu [Department of Otolayngology, Nagoya University School of Medicine (Japan); Ichinose, Nobuyasu [Toshiba Nasu Operations, Tochigi (Japan)

    2002-05-01

    Our objective was to evaluate the frequency of contrast enhancement of the endolymphatic sac in patients with sudden hearing loss. Forty consecutive patients with sudden sensorineural hearing loss (20 males and 20 females; age range 11-82 years), 40 age-matched control subjects, and 5 patients with Meniere's disease were examined using the same imaging protocol on a 1.5-T MR system. Pre- and post-contrast-enhanced T1-weighted 3D spoiled gradient-echo sequence (3D SPGR; TR/TE=23/10 ms, no. of excitations=1, flip angle=30 ) images were obtained using a voxel size of 0.6 x 0.7 x 0.8 mm{sup 3}. Contrast enhancement in the area of the endolymphatic sac was assessed by two radiologists, and the frequency of contrast enhancement was compared between the three study groups. Enhancement of the ipsilateral endolymphatic sac was observed in 30 of the 40 patients with sudden hearing loss (75%). Twenty of these 30 patients also showed enhancement on the contralateral side, and 1 patient showed enhancement only on the contralateral side. Only 1 of the 5 patients with Meniere's disease showed enhancement. Nine of the 40 control subjects (22.5%) showed enhancement (bilateral enhancement in 5 subjects, unilateral in 4). The frequency of enhancement in patients with sudden hearing loss was significantly higher than that in control subjects (P<0.0001) or patients with Meniere's disease (P<0.05). The frequency of contrast enhancement of the endolymphatic sac is significantly increased in patients with sudden hearing loss, but further study is necessary to clarify the relationship between this finding and the pathophysiology of sudden hearing loss. (orig.)

  5. Prothrombotic gene mutations in patients with sudden sensorineural hearing loss and cardiovascular thrombotic disease.

    Science.gov (United States)

    Capaccio, Pasquale; Cuccarini, Valeria; Ottaviani, Francesco; Fracchiolla, Nicola Stefano; Bossi, Anna; Pignataro, Lorenzo

    2009-03-01

    Impaired cochlear perfusion seems to be an important event in sudden sensorineural hearing loss. Prothrombotic gene mutations have been related to vascular disorders and sudden hearing loss. We assessed the prothrombotic risk in 10 patients with sudden sensorineural hearing loss who had previously experienced cardiovascular events to support its vascular pathogenesis. Ten patients underwent hematologic tests (MTHFR C677T/A1298C, prothrombin G20210A, platelet GlyIIIaA1/A2, and V Leiden G1691A genotyping; fibrinogenemia; cholesterolemia: homocysteinemia; folatemia). The results were compared with those of 100 previously investigated patients with sudden hearing loss alone and those of 200 healthy controls. DNA was isolated from peripheral blood leukocytes, and the gene mutations were investigated by polymerase chain reaction and a LightCycler DNA analyzer. Two patients had 2 mutant alleles, 6 had 3, and 2 had 4. The mean homocysteine, cholesterol, and fibrinogen levels were above the upper limit of normal; the mean folate levels were slightly above the lower limit of normal. Multiple mutations were more frequent in the patient group than in the previously analyzed patients and healthy controls. The association between inherited and acquired prothrombotic factors in patients with sudden sensorineural hearing loss and thrombotic diseases in other sites suggests that a multifactorial mechanism may underlie microvascular cochlear impairment. Hematologic investigation, including MTHFR, prothrombin, platelet, and V Leiden genotyping, may help to detect patients at potential risk of recurrent hearing loss and multiple microvascular diseases, and could be usefully performed in otherwise idiopathic sudden sensorineural hearing loss.

  6. [A clinical analysis for sudden sensorineural hearing loss with acoustic neurinoma].

    Science.gov (United States)

    Gong, Qi-lin; Zhou, Ai-dong; Lin, Chang

    2013-04-01

    Retrospectively analyzed the clinical data of sudden sensorineural hearing loss with acoustic neuroma. The clinical data of 467 cases with sudden sensorineural hearing loss were collected between Jan, 2008 and Aug, 2012. Discussed the clinical data which were diagnosed as acoustic neuroma. In 467 cases of sudden sensorineural hearing loss, nine cases were diagnosed as acoustic neuromas (9 ears, 1.93%), two males and seven females, with a age range of 28 to 57 years. Among them, seven cases accompanied with tinnitus, seven cases with vertigo. The hearing results in nine cases, two cases were found to be mild, two were moderate, four were severe, and one was profound hearling loss respectively. Hearing was classified into five types according to audiogram shape (1 of up-sloping, 1 of down-sloping, 2 of mid-frequency, 1 of profound loss, 4 of flat audiogram). Eight cases had abnormal ABR, nine cases with ear ipsilateral stapedius reflex were completely not elicited, seven cases with health ear contralateral stapedius reflex were completely not elicited. Tumors were graded by Koos Grades according to size (7 of grade I, 1 of grade II, 1 of grade IV). Seven small acoustic neuroma was taken waiting strategies. Meanwhile, we use glucocorticoid and improve the microcirculation of the inner ear medication short-termly for these patients. Four patients' hearing were improved. The initial symptoms of some acoustic neuroma are sudden hearing loss, especially the small tumors in internal auditory canal. In order to prevent misdiagnosis, MRI and ABR should be performed as a routine test for sudden sensorineural hearing loss. It is necessary to give appropriate treatment to protecting hearing for the small acoustic neuroma patients whose first symptoms are diagnosed as sudden sensorineural hearing loss.

  7. Takayasu Arteritis of the Coronary Arteries Presenting as Sudden Death in a White Teenager.

    Science.gov (United States)

    Hlavaty, Leigh; Diaz, Francisco; Sung, LokMan

    2015-09-01

    Takayasu arteritis is a rare disease that expresses chronic, large vessel inflammation. The etiology remains unclear and its presentation depends on the affected arteries. With coronary artery involvement, manifestations range from chest pain and shortness of breath to sudden death. We report a case of a 15-year-old white girl who presented with syncope immediately before passing. On autopsy, all 3 major coronary arteries grossly contained multiple proximal lesions that were consistent with Takayasu arteritis, microscopically. Takayasu arteritis solely affecting multiple coronary arteries is exceedingly rare. This report discusses the significance of coronary involvement in Takayasu arteritis at autopsy and sudden death.

  8. Sudden Infant Death Syndrome and Left Ventricular Hypertrabeculation-Hidden Arrhythmogenic Entity?

    Directory of Open Access Journals (Sweden)

    G. Saayman

    2010-09-01

    Full Text Available Left ventricular noncompaction/hypertrabeculation is a condition which is characterized by a highly trabeculated, “spongy” myocardium. It can present at any age with heart failure, arrhythmia and/or thromboembolic events. A wide variety of mutations have been found to be a cause of hypertrabeculation and it is possible that there is a continuum of hypertrophic cardiomyopathy, dilated cardiomyopathy and hypertrabeculation/noncompaction. We present a case of left ventricular hypertrabeculation which presented as sudden infant death syndrome and we propose that this entity may be a hidden cause of arrhythmic death in some infants presenting as sudden infant death syndrome.

  9. 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

    Objectives: To elucidate potential mechanisms for the clarithromycin-induced excess mortality observed in the CLARICOR trial during 2.6 year follow-up of patients with stable coronary artery disease. Methods: Cox analyses using out-of-hospital death as a proxy for sudden death compared to in-hospital...... CV death in patients not on statins at trial entry (HR: 2.61, 95% CI: 1.69–4.05, p administration was significantly associated with increased risk of sudden CV death in stable...

  10. Sudden death due to disseminated cryptococcosis in a child with leukemia in remission.

    Science.gov (United States)

    Lascari, A D; Pearce, J M; Swanson, H

    1997-12-01

    Cryptococcus neoformans typically causes an insidious illness with symptoms related to meningitis or to lung involvement. This is the first reported sudden death due to cryptococcosis, which occurred in a child with leukemia that was in remission. The child had suddenly looked seriously ill and cried with abdominal pain and then died within 25 minutes. Disseminated cryptococcal infection of the lungs, heart, and pancreas was an unexpected finding at autopsy. This clinical experience raises the question whether fungal infections should now be considered in immunosuppressed patients who have an apparent septic collapse.

  11. Clinical Laboratory and Epidemiological Features of Sudden Exanthema in Children Saint-Petersburg

    Directory of Open Access Journals (Sweden)

    E. V. Sharipova

    2016-01-01

    Full Text Available The paper studies the clinical and epidemiological features of one of the acute clinical forms of infection caused by the human herpes virus type 6 — «sudden exanthema » — in children of St. Petersburg. The study involved 149 children hospitalized aged 6 months to 15 years in the period from 2012 to 2014. Sudden rash confirmed by molecular genetic studies in 38 children. The disease is mainly observed in patients of the first two years of life. Rash and toxic syndromes dominated in clinical picture.

  12. Sudden cardiac arrest and coexisting mitral valve prolapse: a case report and literature review

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed

    2016-05-01

    Full Text Available The aetiology of sudden cardiac arrest can often be identified to underlying cardiac pathology. Mitral valve prolapse is a relatively common valvular pathology with symptoms manifesting with increasing severity of mitral regurgitation (MR. It is unusual for severe MR to be present without symptoms, and there is growing evidence that this subset of patients may be at increased risk of sudden cardiac arrest or death. The difficulty lies in identifying those patients at risk and applying measures that are appropriate to halting progression to cardiac arrest. This article examines the association of mitral valve prolapse with cardiac arrests, the underlying pathophysiological process and the strategies for identifying those at risk.

  13. Refractory Granulomatosis with Polyangiitis Presenting as Facial Paralysis and Bilateral Sudden Deafness.

    Science.gov (United States)

    Kim, Sang Hoon; Jung, A Ra; Kim, Su Il; Yeo, Seung Geun

    2016-04-01

    Granulomatosis with polyangiitisis [(GPA) or Wegener granulomatosis] is a multi-system disease characterized by granuloma formation and necrotizing vasculitis. GPA classically shows involvement of the respiratory tracts and the renal system. However, locoregional disease is common and may include otologic manifestations. Although otologic involvement can occur during the course of GPA, no report has described facial palsy with sudden sensorineural total deafness with vertigo as the presenting feature of GPA. This case describes a patient with multiorgan involving resistant form of GPA initially presenting with bilateral profound sudden sensorineural hearing loss and left facial paralysis with vertigo. The condition responded well to treatment with rituximab.

  14. Nationwide study of sudden cardiac death in persons aged 1-35 years

    DEFF Research Database (Denmark)

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

    2011-01-01

    . Death certificates were read independently by two physicians. The National Patient Registry was used to retrieve information on prior medical history. All autopsy reports were read and the cause of death was revised based on autopsy findings. We identified 625 cases of sudden unexpected death (10...... sleep; 89% were out-of-hospital deaths. Highest possible incidence rate of SCD in the young was 2.8 per 100 000 person-years including non-autopsied cases of sudden unexpected death. Excluding those, the incidence rate declined to 1.9 per 100 000 person-years. Conclusions A total of 7% of all deaths...

  15. Myasthenia gravis mimicking stroke: a case series with sudden onset dysarthria.

    Science.gov (United States)

    Tremolizzo, Lucio; Giopato, Federico; Piatti, Maria Luisa; Rigamonti, Andrea; Ferrarese, Carlo; Appollonio, Ildebrando

    2015-06-01

    Myasthenia gravis (MG) is an immune-mediated disorder characterized by fluctuating fatigue of skeletal muscles, often involving extrinsic ocular or bulbar districts. Myasthenia gravis in the elderly is an under-recognized condition, sometimes confused with cerebrovascular disease. Here we present a case series of myasthenia patients which onset was characterized by sudden dysarthria, clearly raising this diagnostic dilemma. In the workout of sudden onset isolated dysarthria, MG should be always considered. In fact, even if myasthenia is a rare condition, lacunar stroke only with this clinical presentation is also unusual, and significant risks may arise (e.g., unexpected myasthenic crisis).

  16. Depressurized pipes decontamination by using circulation foam

    International Nuclear Information System (INIS)

    Damerval, Frederique; Belz, Jacques; Renouf, Marjorie; Janneau, Patrice

    2012-09-01

    Decontamination of pipes remains a necessity in order to reduce the radiation level during maintenance or dismantling operations but it is not so easy to do it, especially in case of a long pipe network. To achieve this operation, the use of chemistry is one of the more relevant methods; moreover, the liquid waste production still remains an issue that it can be avoided by the use of decontamination foams. (authors)

  17. Left-ventricular geometry and risk of sudden cardiac arrest in patients with preserved or moderately reduced left-ventricular ejection fraction.

    Science.gov (United States)

    Aro, Aapo L; Reinier, Kyndaron; Phan, Derek; Teodorescu, Carmen; Uy-Evanado, Audrey; Nichols, Gregory A; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S

    2017-07-01

    The majority of sudden cardiac arrests (SCAs) occur in patients with left-ventricular (LV) ejection fraction (LVEF) >35%, yet there are no methods for effective risk stratification in this sub-group. Since abnormalities of LV geometry can be identified even with preserved LVEF, we investigated the potential impact of LV geometry as a novel risk marker for this patient population. In the ongoing Oregon Sudden Unexpected Death Study, SCA cases with archived echocardiographic data available were prospectively identified during 2002-15, and compared with geographical controls. Analysis was restricted to subjects with LVEF >35%. Based on established measures of LV mass and relative wall thickness (ratio of wall thickness to cavity diameter), four different LV geometric patterns were identified: normal geometry, concentric remodelling, concentric hypertrophy, and eccentric hypertrophy. Sudden cardiac arrest cases (n = 307) and controls (n = 280) did not differ in age, sex, or LVEF, but increased LV mass was more common in cases. Twenty-nine percent of SCA cases presented with normal LV geometry, 35% had concentric remodelling, 25% concentric hypertrophy, and 11% eccentric hypertrophy. In multivariate model, concentric remodelling (OR 1.76; 95%CI 1.18-2.63; P = 0.005), concentric hypertrophy (OR 3.20; 95%CI 1.90-5.39; P geometry as a potential risk stratification tool in patients with preserved or moderately reduced LVEF. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  18. Quantum infinite order sudden approximation for ion-molecule reactions: treatment of the He + H2+ system

    International Nuclear Information System (INIS)

    Baer, M.; Nakamura, H.; Kouri, D.J.

    1986-01-01

    In this work the ion-molecule reaction He + H 2 + (v/sub i/) → HeH + (v/sub f/) + H(v/sub i/ = 0-7, v/sub f/ = 0-2) was studied quantum mechanically in the energy range 1.3 eV ≤ E/sub tot/ ≤ 1.8 eV. The calculations were carried out employing the Reactive Infinite Order Sudden Approximation (RIOSA). The two features characteristic of this system in the above energy range, namely the strong enhancement of the reaction rate with the initial vibrational energy (at a fixed total energy) and the relatively weak dependence of the cross sections on translational energy, were found to be well reproduced in the numerical treatment. The results also revealed the existence of two mechanisms of the exchange process: one is the ordinary mechanism and the other is probably related to the spectator stripping model

  19. Following The Trail: Factors Underlying the Sudden Expansion of the Egyptian Mongoose (Herpestes ichneumon) in Portugal

    Science.gov (United States)

    Barros, Tânia; Carvalho, João; Pereira, Maria João Ramos; Ferreira, Joaquim P.; Fonseca, Carlos

    2015-01-01

    Species range-limits are influenced by a combination of several factors. In our study we aimed to unveil the drivers underlying the expansion of the Egyptian mongoose in Portugal, a carnivore that was confined to southern Portugal and largely increased its range during the last three decades. We evaluated the expansion of the species in three periods (1980-1990, 1990-2000 and 2000-2010), by projecting the presence/absence data of the species in each temporal range and proposed four hypotheses to explain this sudden expansion associated to changes in the barrier effects of human infrastructure and topographic features, and in the availability of suitable areas due to climate change or land use. An exploratory analysis was made using Spearman rank correlation, followed by a hierarchical partitioning analysis to select uncorrelated potential explanatory variables associated with the different hypotheses. We then ran Generalized Linear Models (GLM) for every period for each hypothesis and for every combination of hypotheses. Our main findings suggest that dynamic transitions of land-use coupled with temperature and rainfall variations over the decades are the main drivers promoting the mongoose expansion. The geographic barriers and the human infrastructures functioned as barriers for mongoose expansion and have shaped its distribution. The expansion of the Egyptian mongoose across the Portuguese territory was due to a variety of factors. Our results suggest a rapid shift in species range in response to land-use and climate changes, underlining the close link between species ranges and a changing environment. PMID:26266939

  20. Seasonal Timing of Infant Bronchiolitis, Apnea and Sudden Unexplained Infant Death.

    Directory of Open Access Journals (Sweden)

    Chantel D Sloan

    Full Text Available Rates of Sudden Unexplained Infant Death (SUID, bronchiolitis, and central apnea increase in winter in temperate climates. Though associations between these three conditions are suggested, more work is required to establish if there is a causal pathway linking bronchiolitis to SUID through inducing central apnea. Utilizing a large population-based cohort of infants studied over a 20-year period (n = 834,595, from birth years 1989-2009, we analyzed ecological associations between timing of SUID cases, bronchiolitis, and apnea healthcare visits. Data were analyzed between 2013 and 2015. We used a Cox Proportional Hazards model to analyze possible interactions between maternal smoking and maternal asthma with infant bronchiolitis on time to SUID. SUID and bronchiolitis both occurred more frequently in winter. An increase in bronchiolitis clinical visits occurred within a few days prior to apnea visits. We found a temporal relationship between infant bronchiolitis and apnea. In contrast, no peak in SUID cases was seen during peaks of bronchiolitis. Among those without any bronchiolitis visits, maternal smoking was associated with an increased risk of SUID: Hazard Ratio (HR of 2.38 (95% CI: 2.11, 2.67, p-value <0.001. Maternal asthma was associated with an increased risk of SUID among infants with at least one bronchiolitis visit: HR of 2.40 (95% CI: 1.04, 5.54, p-value = 0.04. Consistent trends between bronchiolitis, apnea, and SUID were not established due to small numbers of SUID cases. However, interaction analysis revealed potential differential associations of bronchiolitis and SUID by maternal smoking, maternal asthma status.